CN100365849C

CN100365849C - Negative electrode for nonaqueous secondary battery, process of producing the negative electrode, and nonaqueous secondary battery

Info

Publication number: CN100365849C
Application number: CNB200380103987XA
Authority: CN
Inventors: 武者信一; 本田仁彦; 坂口善树; 安田清; 茂出木晓宏; 松岛智善; 田口丈雄; 谷口和子; 土桥诚
Original assignee: Mitsui Mining and Smelting Co Ltd
Current assignee: Mitsui Mining and Smelting Co Ltd
Priority date: 2002-11-29
Filing date: 2003-11-25
Publication date: 2008-01-30
Anticipated expiration: 2023-11-25
Also published as: CN1714463A

Abstract

Disclosed is a negative electrode for a nonaqueous secondary battery comprised of a current collector and an active material structure containing an electro-conductive material having low capability of forming a lithium compound on at least one side of the current collector, the active material structure containing 5 to 80% by weight of active material particles containing a material having high capability of forming a lithium compound. The active material structure preferably has an active material layer containing the active material particles and a surface coating layer formed on the active material layer.

Description

Negative electrode for nonaqueous secondary battery and manufacture method thereof and nonaqueous electrolytic solution secondary battery

Technical field

The present invention relates to negative electrode for nonaqueous secondary battery, more detailed saying relates to a kind of negative pole that can access the nonaqueous electrolytic solution secondary battery that energy density Gao Bingneng embedding in large quantities, removal lithium embedded and cycle life is improved.In addition, the present invention relates to possess the nonaqueous electrolytic solution secondary battery of this negative pole.

Background technology

The secondary cell of portable phone and personal computer mainly uses lithium rechargeable battery now.Its reason is because this battery and other secondary cells relatively have high energy density.Follow in recent years portable phone and the multifunction of personal computer, their power consumption significantly increases, and more and more needs jumbo secondary cell., if only use present electrode active material, can anticipation can be difficult to adapt to the demand in future soon.

The negative electrode active material of lithium rechargeable battery generally uses graphite.Now, the Sn with 5-10 capacity electromotive force doubly of graphite is that alloy and Si are that the exploitation of alloy is very active.For example, having proposed to use mechanical alloy fusion process, cylinder casting and gas atomization manufactured Sn-Cu is the scheme (J.Electrochem.Soc., 148 (5), A471-A481 (2001)) of the thin slice of alloy.In addition, also having proposed with manufacturing Ni-Si such as gas atomizations is that alloy, Co-Si are the scheme (spy opens the 2001-297757 communique) of alloy., though these alloy capacity are big, it is big to exist irreversible capacity, also has the short problem of cycle life, does not therefore reach practicability as yet.

To the Copper Foil electrotinning that uses as collector body, the trial that is used for the electrode that negative pole uses is then also being carried out (spy opens the 2001-68094 communique)., about the capacity electromotive force silicon also bigger than tin, because silicon is the element that can not electroplate, the exploitation that therefore contains the plating Copper Foil that its lithium rechargeable battery uses does not also have report.

Above-mentioned Si is that alloy or Sn are that alloy and Al are alloy, is the negative electrode active material with high charge/discharge capacity, but because repeated charge, its volume can change widely, therefore the problem that has micronizing and peel off from collector body.So, proposed on the conductive metal paper tinsel, to be coated with and contained the negative electrode active material of Si or Si alloy and the mixture of conductive metal powder, and under non-oxidizing atmosphere sintering, prevent the scheme that negative electrode active material peels off (spy open flat 11-339777 communique, spy open 2000-12089 communique, spy are opened the 2001-254261 communique, the spy opens the 2002-260637 communique) thus.In addition, also propose using plasma CVD method or sputtering method good adhesion ground on collector body and formed the Si film, prevented the scheme (spy opens the 2000-18499 communique) that this film is peeled off thus.And then, just all the time carrying out (spy open flat 10-312804 communique, spy are opened the 2001-243946 communique, the spy opens the 2001-307723 communique) based on the exploitation of a lot of intermetallic compound of Sn or Si., even use said method, can not prevent to follow caused this negative electrode active material of micronizing peeling off of the negative electrode active material that discharges and recharges fully from collector body.

In addition, disclose a kind of negative pole of such formation, formed and contain the layer that constitutes the metallic element of alloy with lithium, on this floor, formed the floor (spy opens flat 8-50922 communique) that does not constitute the metallic element of alloy with lithium.Communique is pointed out in view of the above, adopts the negative pole of this formation can suppress to contain layer micronizing that discharges and recharges because of battery that constitutes the metallic element of alloy with lithium., according to the record of the embodiment of this communique, at the layer that does not the most constitute the metallic element of alloy with lithium of surperficial formation, its thickness is 50nm as thin as a wafer, therefore this layer can not fully be covered contain with the metallic element of lithium formation alloy layer the surface.Under the sort of occasion, when contain with lithium constitute alloy metallic element layer because of battery discharge and recharge micronizing the time, then can not fully suppress it and come off.On the contrary, when not with lithium constitute alloy metallic element layer fully lining contain the occasion on surface of layer that constitutes the metallic element of alloy with lithium, this layer can hinder electrolyte, and to constitute the laminar flow of metallic element of alloy moving with lithium to containing, and is difficult to take place sufficient electrode reaction.The technology that has aforesaid opposite function simultaneously proposes as yet.

Different is, as the collector body that lithium rechargeable battery is used, and the known collector body that has the surface to form the concavo-convex collector body of appropriateness and formed the minute aperture that connects at thickness direction.For example, proposed a kind of collector body, it constitutes three-dimensional net structure by the intercommunicating pore that connects at thickness direction and the porous electrolytic metal paper tinsel that forms constitutes (spy opens flat 8-236120 communique).The manufacture method of this metal forming is, surperficial metal electrodeposition at the drum cathode forms its metal foil layer, it is peeled off when making the electrolytic metal paper tinsel from the drum cathode, the surface of the bulging cathode that exposes after peeling off forms the oxide scale film that thickness is at least 14nm, forms the electrolytic metal paper tinsel above the oxide scale film at this., the percent opening of this metal forming and perforate aperture depend on the thickness of the oxide scale film that forms on the cathode at drum, and this oxide scale film always little by little peels off with paper tinsel, so the control in percent opening and perforate aperture is difficult.In addition, because the perforate aperture is smaller and three-dimensional net structure is arranged, therefore the active material paste that is coated with respectively in the table of paper tinsel is difficult to direct contact each other.Therefore we think that the degree that the adhesiveness that makes paste and paper tinsel increases is limited.

In order to solve the problem that above-mentioned metal forming has, the present application people has proposed a kind of porous copper foil (with reference to the international brochure that discloses No. 00/15875) previously: be to make the copper particle mutual plane ground of in-plane average grain diameter 1-50 μ m engage the porous copper foil that forms by electrolysis, its light transmission is more than 0.01% the time, and the difference of the surface roughness on the surface of the surface roughness on the surface of cathode plane side and its opposition side is by the scope of Rz at 5-20 μ m when forming paper tinsel.When this Copper Foil was used as the collector body of lithium rechargeable battery, obtain following favourable effect: (1) electrolyte easily flowed, and limited amount electrolyte is soaked into to active material equably; (2) giving and accepting of Li ion during difficult obstruction discharges and recharges and electronics; (3) owing to have the concavo-convex of appropriateness on the surface, therefore with the adhesiveness excellence of active material., in the manufacture method of this porous copper foil, because behind drum type cathode electrolysis copper, this Copper Foil to the state peeled off from this cathode will be implemented various processing, therefore the state of Copper Foil becomes unstable, and the property handled does not claim good, is not easy a large amount of productions.In addition, this porous copper foil is being used as collector body, in the negative electrode for nonaqueous secondary battery that its each face coating cathode agent forms, embedding is taken off in the embedding of lithium of resulting from, and negative electrode active material easily comes off, the problem that has cycle characteristics to reduce easily.

Summary of the invention

Therefore, the objective of the invention is, the nonaqueous electrolytic solution secondary battery that can eliminate the negative electrode for nonaqueous secondary battery of above-mentioned various shortcoming and possess this negative pole is provided.

The invention provides a kind of negative electrode for nonaqueous secondary battery, it is characterized in that, on the single face of collector body or two sides, form the active material structure of the low conductive material of the formation ability that contains lithium compound, in this active material structure, contain the active material particle of the high material of the formation ability that contains lithium compound of 5-80 weight %.

In addition, the invention provides the preferred manufacture method of a kind of manufacture method of negative electrode for nonaqueous secondary battery as above-mentioned negative pole, it is characterized in that, the slurry coating that will contain above-mentioned active material particle, conductive carbon material, adhesive and retarder thinner is on above-mentioned collector body surface, make dried coating film form active material layer, then, on this active material layer, carry out the plating of the low above-mentioned conductive material of the formation ability of lithium compound, form surface-coated layer.

In addition, the invention provides a kind of manufacture method of negative electrode for nonaqueous secondary battery another preferred manufacture method as above-mentioned negative pole, it is characterized in that, the slurry coating that will contain above-mentioned active material particle, conductive carbon material, adhesive and retarder thinner is on above-mentioned collector body surface, make dried coating film form active material layer, then, on this active material layer, implement sputtering method, chemical vapor coating method or physical vapor vapour deposition method, the surface-coated layer of the above-mentioned conductive material that the formation ability of formation lithium compound is low.

In addition, a kind of manufacture method of negative electrode for nonaqueous secondary battery another preferred manufacture method as above-mentioned negative pole of the present invention is provided, it is characterized in that, on foils, form by the lining body that constitutes with the inhomogeneous material of the constituent material of above-mentioned collector body with the thickness of 0.001-1 μ m, make the constituent material electrolysis of above-mentioned collector body go out to form this collector body by plating in the above, to contain above-mentioned active material particle, conductive carbon material, the slurry coating of adhesive and retarder thinner is on above-mentioned collector body surface, make dried coating film form active material layer, on above-mentioned active material layer, carry out the plating of the low above-mentioned conductive material of the formation ability of lithium compound, form surface-coated layer, above-mentioned collector body is peeled off from above-mentioned foils.

In addition, the invention provides a kind of nonaqueous electrolytic solution secondary battery, it is characterized in that, possess above-mentioned negative pole.

Description of drawings

Fig. 1 is the electron micrograph picture on surface of an embodiment of expression negative pole of the present invention.

Fig. 2 is the electron micrograph picture in cross section of an embodiment of expression negative pole of the present invention.

Fig. 3 is the electron micrograph picture in cross section of another embodiment of expression negative pole of the present invention.

Fig. 4 is the electron micrograph picture in cross section of the another embodiment of expression negative pole of the present invention.

Fig. 5 (a)-Fig. 5 (f) is the process chart of expression as the manufacture method of the multicellular metal foil of the use of the collector body in the negative pole of the present invention.

Embodiment

Following according to its embodiment preferred with reference to description of drawings the present invention.Express the electron micrograph picture on surface of an embodiment of negative pole of the present invention among Fig. 1.Express the electron micrograph picture in cross section of an embodiment of negative pole of the present invention among Fig. 2.Negative pole 1 is to constitute like this, on the single face of collector body 2 or two sides, form the active material structure 5 of the low conductive material of the formation ability that contains lithium compound, in this active material structure 5, comprise the active material particle of the high material of the formation ability that contains lithium compound.Specifically as shown in Figure 2, in the active material structure 5 that is formed with the particle layer that possesses active material (below be called active material layer) 3 on the single face of collector body 2 or the two sides and is positioned at the surface-coated layer 4 on this layer 3.

Collector body 2 is made of the metal of the collector body that can become nonaqueous electrolytic solution secondary battery.Especially preferably the metal by the collector body that can become lithium secondary battery constitutes.As above-mentioned metal, can list the alloy of copper for example, iron, cobalt, nickel, zinc or silver or these metals etc.Especially preferably use copper or copper alloy or nickel or nickel alloy among these metals.Use the occasion of copper, collector body uses with the state of Copper Foil.This Copper Foil for example separates out by the electrolysis of having used copper-containing solution and obtains, and its thickness wishes that 2-100 μ m, special hope are 10-30 μ m.Particularly adopt the special Copper Foil that the method put down in writing in the 2000-90937 communique obtains of opening,, therefore preferably used because thickness is below the 12 μ m as thin as a wafer.When using the electrolytic metal paper tinsel, preferred because the adhesiveness of collector body 2 and active material layer 3 improves as collector body 2.Its reason is that the surface of electrolytic metal paper tinsel has the roughness of appropriateness.

Active material layer 3 is the layers that comprise the active material particle 7 of the high material of the formation ability that contains lithium compound.Can use for example silicon based material, tin based material, aluminium based material, germanium based material as this material.Active material particle 7 particle diameters represent with maximum particle diameter, and then 50 μ m or following preferably are more preferably 20 μ m or following.In addition, when using D ₅₀During the particle diameter of value representation active material particle 7, preferably 0.1-8 μ m, especially preferably 0.3-1 μ m.When maximum particle diameter surpasses 50 μ m, easily cause coming off of active material particle 7, often the lifetime of electrode.The lower limit of particle diameter is not particularly limited, and is the smaller the better.In view of the manufacture method (about its Production Example back narration) of active material particle 7, lower limit is about 0.01 μ m.The particle diameter of active material particle 7 is measured by micro-spike, electron microscope observation (SEM observation).In addition, in the present invention, preferably only contain active material particle 7, but it is also harmless to contain the active material particle 7 that surpasses above-mentioned particle diameter on a small quantity in the scope of not damaging effect of the present invention with above-mentioned particle diameter.

Exist hole in the preferred active material layer 4.Because the existence of this hole, active material particle 7 embeddings and removal lithium embedded and expand and shrink caused stress and relaxed.Consider that from this viewpoint the ratio of the hole in the active material layer 4 about 1-30 volume %, about 5-30 volume %, most preferably is about 5-9 volume % especially preferably preferably.The ratio of hole can be obtained by electron microscopic minute surface scanning imagery (mapping).For the ratio that makes hole in above-mentioned scope, for example form active material layer with method described later after, press process gets final product under suitable condition.

Preferably in active material layer 3, also contain conductive carbon material except active material particle 7.Further pay active material structure 5 in view of the above with electronic conductivity.The amount of contained conductive carbon material in the active material layer 3, preferably 0.1-20 weight %, especially preferably 1-10 weight % from this viewpoint.Conductive carbon material is the form of particle preferably, considers that from the aspect of further paying electronic conductivity its particle diameter is preferably below the 40 μ m, especially preferably below the 20 μ m.The particle diameter lower limit of this particle is not particularly limited, and is more little preferred more.In view of the manufacture method of this particle, its lower limit is about 0.01 μ m.As conductive carbon material, can list for example acetylene carbon black, graphite etc.

The surface of surface-coated layer 4 active material layer 3 that is being covered thickly continuously, active material particle 7 does not expose in negative terminal surface in fact.Surface-coated layer 4 is with the roughly the same thickness surface of active material layer 3 that is being covered, but also has its a part of 4a to enter into active material layer 3.

In addition, surface-coated layer 4 also has the part that enters into active material layer 3 and further arrive collector body 2.And, also have the constituent material arrival collector body 2 of surface-coated layer 4 and the part of soaking in the whole zone of the thickness direction of active material layer 3.The constituent material of surface-coated layer 4 enters into active material layer 3 more, and the conductivity of negative pole integral body improves more, thereby is preferred.In addition, the network configuration that the constituent material that adopts surface-coated layer 4 forms can prevent the coming off of expanding and shrink of following of active material particle 7, so preferred.

Active material particle 7 does not need by the lining fully of surface-coated layer 4, and its part is exposed also passable., take off the micronizing of active material particle 7 of embedding from the embedding that prevents to result from lithium and viewpoint that this active material particle 7 of causing comes off, preferred active material particle 7 is by the lining fully of surface-coated layer 4.Even active material particle 7 is by the lining fully of surface-coated layer 4, electrolyte and lithium also can be impregnated into the inside of surface-coated layer 4 from fine pore 6 described later, with active material particle 7 reactions.

Fig. 3 and Fig. 4 express active material layer 3 by another example of the negative pole of surface-coated layer 4 state that is covered fully.In Fig. 3 and Fig. 4, on the collector body 2 that constitutes by copper, form the active material layer 3 that contains silicon-copper alloy particles, the surface-coated layer 4 that is made of copper is positioned on the active material layer 3.Active material layer 3 is being covered fully by surface-coated layer 4.In surface-coated layer 4, observe the fine fracture portion of extending at its thickness direction.And, observe hole between the alloy particle in the active material layer 3.In Fig. 3, distinguish that the part of surface-coated layer 4 enters into active material layer 3, the surface of alloy particle is being covered by copper.On the other hand, in Fig. 4, surface-coated layer 4 is not to enter into active material layer 3 so, and two-

layer

3,4 distinguish more clearly.The difference of the aforesaid form among Fig. 3 and Fig. 4 results from the manufacture method of negative pole.

Because it is elongated that the secondary cell that active material layer 3, has therefore used negative pole of the present invention by surface-coated layer 4 lining fully and the battery in past are compared the life-span.Because active material particle 7 is closed in the surface-coated layer 4,, also can keep and the electrically contacting of surface-coated layer 4 even therefore taking off embedding because of the embedding of lithium causes active material particle 7 micronizings.Its result has kept electronic conductivity, has suppressed the function reduction as negative pole.And can obtain the long lifetime of negative pole.Particularly when the part of surface-coated layer 4 entered into active material layer 3, the current collection function was more kept with producing effect.When being formed on collector body on its original state active material, because embedding is taken off in the embedding of lithium, this active material micronizing also isolates out from collector body.Its result takes place such as the problem as the function reduction of negative pole, irreversible capacity increase, efficiency for charge-discharge reduction, short lifeization etc.

Surface-coated layer 4 from oxidation that prevents this coating 4 and the viewpoint that comes off, is made of the low conductive material of ability that forms of lithium compound.As above-mentioned conductive material, alloy of copper, silver, nickel, cobalt, chromium, iron, indium and these metals (for example alloy of copper and tin) etc. for example.Among these metals, preferably use copper, silver, nickel, chromium, the cobalt of the low especially metal of the formation ability of its lithium compound and contain the alloy of these metals.In addition, as above-mentioned conductive material, also can use Markite and conductivity paste etc.So-called " the formation ability of lithium compound is low " is even mean and do not form intermetallic compound or solid solution with lithium or formed, but lithium wherein also is trace or very unsettled.

For surface-coated layer 4, be formed with the fine pore 6 that a large amount of thickness directions to this coating 4 extends on its surface.Fine pore 6 is crooked on one side to be extended on one side.Part among a large amount of fine pores 6 is extended and arrival active material layer 3 to the thickness direction of surface-coated layer 4.From the occasion of the surface-coated layer 4 of cross-section, fine pore 6 is the wide fine holes about the about 30 μ m of about 0.1 μ m-that are.Though fine, fine pore 6 must have the wide of degree that nonaqueous electrolytic solution can soak into.Especially specific surface tension is little mutually for the electrolyte of nonaqueous electrolytic solution and water system, even therefore the wide little of fine pore 6 also can be soaked into fully.

By the perforated area of electron microscope from 4 o'clock fine pore 6 of the surface-coated layer of viewed in plan, from guaranteeing soaking into fully of nonaqueous electrolytic solution, can prevent that the viewpoint that comes off of active material layer 3 from setting out simultaneously effectively, preferably on average be 0.1-100 μ m ², 1-30 μ m especially preferably ²About.In addition, because same reason, by electron microscope during from viewed in plan coating 4, what kind of no matter takes observe the visual field, and all existing individual, special 3-10 the fine pore 6 of 1-30 in the square field range of 100 μ m * 100 μ m is more satisfactory (this value is called distributive law).And, because same reason, by electron microscope from the surface-coated layer of viewed in plan 4 o'clock, the perforated area summation of fine pore 6 is with respect to the ratio (this ratio is called percent opening) of observing the visual field area preferably 0.1-10%, 1-5% especially preferably.

According to shown in Figure 1, can confirm to have or not fine pore 6 by electron microscope observation, but because fine pore 6 wide minimum, even therefore according to circumstances sometimes electron microscope observation can not judge clearly that it has or not existence.In such occasion, have or not the method for fine pore 6 as judgement, the present invention adopts in the following method.The negative pole that use becomes the judgement object that has or not of fine pore 6 constitutes battery, once discharges and recharges.After that, with electron microscope observation negative pole cross section, cross section structure with discharge and recharge before than the occasion that variation has taken place, be judged as and formed fine pore 6 in the negative pole before discharging and recharging.Cross section structure with discharge and recharge before than the reason that changes, the fine pore 6 arrival active material layers 3 that are non-aqueous solution electrolysis liquid by existing in the negative pole before discharging and recharging, lithium ion in the nonaqueous electrolytic solution and active material particle 7 react and cause.

By forming fine pore 6, nonaqueous electrolytic solution can fully soak into to active material layer 3, reacts fully with active material particle 7.In addition, the active material particle 7 that causes by discharging and recharging micronizing caused comes off, the same according to previous narration is because of surface-coated layer 4 of active material layer 3 surfaces that are covered thickly is prevented.That is to say,, therefore take off the coming off of active material particle 7 that embedding causes and prevented effectively by the embedding of lithium because active material particle 7 is by 4 sealing of surface-coated layer.In addition, can prevent the generation of the active material particle 7 that electricity is isolated effectively, keep the current collection function.Its result can suppress the function reduction as negative pole.And then can obtain the long lifetime of negative pole.Particularly when a part of 4a of surface-coated layer 4 enters into active material layer 3, can more effectively keep the current collection function.Like this, used the secondary cell of negative pole of the present invention, the energy density of its per unit volume and per unit weight is compared with the battery in past, becomes very big, and becomes the long-life.

Fine pore 6 can enough various methods form.For example, can form by the surface-coated layer 4 of press process under suitable condition.Particularly preferred method is to form surface-coated layer 4 by electroplating like that as described later, forms fine pore in this formation.More detailed saying and since active material layer 3 according to previous narration equally be the layer that comprises active material particle 7, so the surface of this active material layer 3 becomes trickle concaveconvex shape.That is to say, become the state that plating avtive spot of easily growing up and the site that is difficult for growing up mix existence.When the active material layer 3 enterprising electroplatings at such state, the growth of plating takes place irregular, and the particle of the constituent material of surface-coated layer 4 can become to grow up to the polycrystalline shape.The growth of crystal is carried out, when adjacent crystal is touched, at that part of formation hole.The hole of Xing Chenging is communicated with in a large number like this, forms fine pore 6 thus.According to the method, it is very fine that the structure of fine pore 6 becomes.In addition, can easily form the fine pore 6 that the thickness direction to surface-coated layer 4 extends.And according to this method, owing to surperficial coating 4 is not applied the external force of press process etc., therefore surface-coated layer 4 and then negative pole 1 can not sustain damage.

From preventing coming off and fully keeping the current collection functional point of view and consider of active material particle 7 effectively, the preferred 0.3-50 μ of the thickness m of surface-coated layer 4, especially preferably 0.3-10 μ m, most preferably be 1-10 μ m.Even form surface-coated layer 4 thickly, because of being formed with fine pore 6, soaking into also of nonaqueous electrolytic solution can be guaranteed reliably.Consider that from the aspect of fully guaranteeing capacity of negative plates the thickness of active material layer 3 is 1-100 μ m, 3-40 μ m especially preferably preferably.Comprise surface-coated layer 4 and active material layer 3 active material structure 5 thickness preferably 2-100 μ m, especially preferably about 2-50 μ m.And, consider that from the aspect of the miniaturization of battery and high-energy-densityization the thickness of negative pole integral body is 2-200 μ m, 10-100 μ m especially preferably preferably.

The amount that comprises the active material particle 7 in the active material structure 5 of active material layer 3 and surface-coated layer 4 is 5-80 weight %, and preferably 10-50 weight % is more preferably 20-50 weight %.When the quantity not sufficient 5 weight % of active material particle 7, be difficult to fully improve the energy density of battery.On the other hand, when surpassing 80 weight %, easily cause coming off of active material particle 7, produce the problem of irreversible capacity increase, efficiency for charge-discharge reduction, short lifeization etc.

As active material particle 7, the particle, (2) that for example can list (1) elementary silicon or tin simple substance be particle of forming at the particle surface coated metal of elementary silicon or tin simple substance of the stuff and other stuff, (6) of the compound particles of compound particles, (5) silicon or the tin and the metal of stuff and other stuff, (4) silicon or the tin and the metal of the particle of stuff and other stuff, (3) silicon or the tin of the particle of silicon or tin and carbon particle and metallic and metallic etc. at least.Above-mentioned each particle can be distinguished two or more uses of using or suiting to make up (1)-(6) separately.When using the particle of (2), (3), (4), (5) and (6),, have that further inhibition is taken off embedding by the embedding of lithium and the micronized advantage of the active material particle 7 that causes with the occasion ratio of the particle of elementary silicon that uses (1) or tin simple substance.This advantage occasion at the particle that uses (5) especially is more remarkable.In addition, in the occasion of using silicon, having can be to paying the advantage of electronic conductivity as the silicon of semi-conductive shortage electronic conductivity.

Particularly in the mangcorn molecular occasion of active material particle 7 by the silicon at least and the carbon of (2), when cycle life improved, capacity of negative plates increased.Its reason is as follows, and carbon, the graphite that particularly uses in negative electrode for nonaqueous secondary battery have feature: help the embedding of lithium to take off embedding, have the capacity of negative plates about 300mAh/g, and the volumetric expansion when embedding lithium is very little.On the other hand, the feature that has of silicon is: with graphite 10 times or more times is the capacity of negative plates about 4200mAh/g.But the volumetric expansion during the embedding lithium of silicon reaches about 4 times of graphite.So, mix the carbon of pulverizing silicon and graphite and so on when use machinery to grind method etc. with the ratio of defined, when making particle diameter for the powder that is mixed by homogeneous of about 0.1-1 μ m, the volumetric expansion of the silicon when embedding lithium is relaxed by graphite, cycle life improves, and also obtains the capacity of negative plates about 1000-3000mAh/g.The blending ratio of silicon and carbon, the amount of preferred silicon is 10-90 weight %.On the other hand, the amount of carbon 90-10 weight % preferably.If consist of in this scope, then can obtain the high capacity of battery and the long lifetime of negative pole.In this stuff and other stuff, do not form the compound of carborundum etc.

The occasion that active material particle 7 is made up of the particle of (2), this particle also can also contain the stuff and other stuff of other metallic elements, 3 kinds or more kinds of element outside silicon or tin and carbon.As metallic element, list a kind or multiple element being selected among Cu, Ag, Li, Ni, Co, Fe, Cr, Zn, B, Al, Ge, In, V, Ti, Y, Zr, Nb, Ta, W, La, Ce, Pr, Pd and the Nd.

Active material particle 7 is occasions of the stuff and other stuff of the silicon of (3) or tin and metal, as the contained metal of this stuff and other stuff, list (wherein from Cu, Ag, Li, Ni, Co, Fe, Cr, Zn, B, Al, Ge, Sn, particle 7 contains except the occasion of tin), a kind or multiple element selecting among Si (wherein, particle 7 contains except the occasion of silicon), In, V, Ti, Y, Zr, Nb, Ta, W, La, Ce, Pr, Pd and the Nd.Among these metals, preferred Cu, Ag, Ni, Co, Ce particularly consider from the low aspect of the formation ability of electronic conductivity excellence and lithium compound, preferably use Cu, Ag, Ni.In addition, as above-mentioned metal when using Li, then in negative electrode active material, contained lithium metal in advance, can produce advantage, so preferably because of irreversible capacity reduces, efficiency for charge-discharge improves and the reduction of volume change brings cycle life raising etc.In the stuff and other stuff of (3), the amount of silicon or tin is 30-99.9 weight % preferably, and especially preferably 50-95 weight % most preferably is 75-95 weight %.On the other hand, with the amount of the metal headed by copper 0.1-70 weight % preferably, especially preferably 5-50 weight % most preferably is 5-30 weight %.If consist of in this scope, then can obtain the high capacity of battery and the long lifetime of negative pole.

(3) stuff and other stuff for example can adopt following method manufacturing.At first, mix silicon particle or tin particle and, utilize pulverizer to carry out the mixing and the pulverizing of these particles simultaneously with the metallic of the metal headed by the copper.Can use vertical ball mill, aeropulverizer, cyclonic separation grinding machine, coating shaking machine, fine gtinding machine etc. as pulverizer.The pulverizing of having used these pulverizers can be dry type and wet type wantonly a kind, but from the viewpoint of small particle diameterization, preferably case of wet attrition.The particle diameter of these particles before pulverizing is preferably about 20-500 μ m.By the mixing and the pulverizing of pulverizer, obtain the particle that silicon or tin and above-mentioned metal mix equably.By suitably controlling the service conditions of pulverizer, the particle diameter that makes resulting particle is for for example below the 40 μ m.Obtain the stuff and other stuff of (3) in view of the above.

Active material particle 7 is occasions of the compound particles of the silicon of (4) or tin and metal, this compound comprises the alloy of silicon or tin and metal, is 1) solid solution, 2 of silicon or tin and metal) intermetallic compound or 3 of silicon or tin and metal) in two-phase among solid solution, silicon or the tin of, metal single phase single-phase, silicon or tin and metal and the intermetallic compound of metal or the more heterogeneous complex of forming wantonly a kind by silicon or tin.As above-mentioned metal, can use the same metal of metal that contains in the stuff and other stuff with (3).The composition of silicon in the compound particles (4) or tin and metal, same with the stuff and other stuff of (3), the amount of preferred silicon or tin is 30-99.9 weight %, the amount of metal is 0.1-70 weight %.Preferred composition is selected suitable scope according to the manufacture method of compound particles.For example, this compound is the binary system alloy of silicon or tin and metal, uses quench described later to make the occasion of this alloy, and the amount of wishing silicon or tin is 40-90 weight %.On the other hand, with the amount of the metal headed by copper 10-60 weight % preferably.

At above-claimed cpd is the ternary system of silicon or tin and metal or the occasion of the alloy of polynary system more, further contains the element that is selected from B, Al, Ni, Co, Fe, Cr, Zn, In, V, Y, Zr, Nb, Ta, W, La, Ce, Pr, Pd and Nd in the binary system alloy that can formerly narrate on a small quantity.In view of the above, obtain micronizing and be suppressed this additional effect.In order to improve this effect more, these elements preferably contain 0.01-10 weight % in the alloy of silicon or tin and metal, especially preferably contain 0.05-1.0 weight %.

(4) compound particles is the occasion of alloy particle, becomes fine size and homogeneous dispersion from the crystallite by alloy, suppresses micronizing, keeps the aspect of electronic conductivity to consider that this alloy particle preference is as adopting the quench manufacturing of following explanation.In this quench, at first prepare to contain silicon or tin and with the motlten metal of the raw material of the metal headed by the copper.Raw material is by high frequency fusing becoming motlten metal.The scale of silicon in the motlten metal or tin and other metals is decided to be aforesaid scope.Be preferably 1200-1500 ℃, be preferably 1300-1450 ℃ especially fastening temperature of melt metal with the pass of chilling condition.Use the mold casting to obtain alloy by this motlten metal.That is, this motlten metal is poured in copper or the mold made of iron, obtain by the ingot casting of the alloy of chilling.This ingot casting is pulverized and screening, for example particle diameter 40 μ m or following particle are used for the present invention.Also can use the cylinder casting to replace this mold casting.That is, the side face to the cylinder made of copper of high speed rotating penetrates motlten metal.The rotating speed of cylinder is considered to be preferably rotating speed 500-4000rpm from the viewpoint that makes the motlten metal chilling, is preferably 1000-2000rpm especially.Occasion represent the rotating speed of cylinder with peripheral speed is preferably 8-70m/sec, is preferably 15-30m/sec especially.By the motlten metal of use with the temperature of the above-mentioned scope of cylinder chilling of the speed rotation of above-mentioned scope, cooling rate reaches 10 ²K/sec is above, especially preferably reach 10 ³The high speed that K/sec is above.Emitted motlten metal on cylinder by chilling and become thin body.Should approach body and pulverize, sieve, for example particle diameter 40 μ m or following particle be used for the present invention.Replace this quench, the using gases atomization to the inert gases such as pressure winding-up argon of 1200-1500 ℃ motlten metal with 5-100atm, carries out micronize and chilling, also can access desired particle.And, as method for distinguishing, also can use arc-melting method and machinery to grind method.

Active material particle be the silicon of (5) or tin and metal compound particles, with the occasion of the stuff and other stuff of the particle of metal, as this compound particles, can use the same particle of compound particles with (4) of previous narration.On the other hand, as the particle of metal, can use the same particle of particle of the metal that uses in the stuff and other stuff with (3) of previous narration.The metallic element of metallic element that compound particles is contained and formation metallic can be of the same race, also can be not of the same race.Particularly when the contained metallic element of compound particles be nickel, copper, silver or iron, when the metallic element that constitutes metallic is nickel, copper, silver or iron, in active material layer 3, easily form the network configuration of these metals.Its result, electron gain conductibility improve, prevent that active material particle 7 from shrinking the favourable effect that comes off etc. because of expanding, so preferably.From this viewpoint, contained metallic element of compound particles and the metallic element that constitutes metallic are preferably of the same race.(5) active material particle, adopt with the same method of the manufacture method of the compound particles of (4) of previous narration and at first obtain compound particles, obtain by this compound particles and metallic are mixed according to the manufacture method of the stuff and other stuff of (3) of previous narration.The ratio of silicon in the compound particles or tin and metal, both ratio that can be decided to be in the compound particles with (4) of previous narration is identical.In addition, the ratio of compound particles and metallic, the ratio that can be decided to be the particle of silicon in the stuff and other stuff with (3) of previous narration or tin and metallic is identical.Beyond these, for the aspect that the active material particle of (5) does not specify, the explanation that the suitable compound particles that is suitable for for the stuff and other stuff of (3) of previous narration or (4) is described in detail.

Active material particle 7 is be covered occasions of the particle (this particle is called the coating metal particle) that metal forms of the particle surface at elementary silicon or tin simple substance of (6), as coated metal, same metals (but except Li) such as the metal that contains in the particle of (3) or (4) of use and previous narration, for example copper.The silicon in the coating metal particle or the amount of tin are preferably 70-99.9 weight %, are preferably 80-90 weight % especially, most preferably are 85-95 weight %.On the other hand,, be preferably 0.1-30 weight %, be preferably 1-20 weight % especially, most preferably be 5-15 weight % with the amount of the coated metal headed by the copper.The coating metal particle for example uses the electroless plating method manufacturing.In this electroless plating method, at first prepared silicon particle or tin particle are suspended and are contained with the plating of the coated metal headed by the copper and bathed.In this plating was bathed, chemical plating silicon particle or tin particle made this particle surface above-mentioned coated metal that is covered.The silicon particle during plating is bathed or the concentration of tin particle are preferably about 400-600g/L.As the occasion of above-mentioned coated metal, preferably make in advance in the plating bath and contain copper sulphate, Rochelle salt etc. at electroless copper.This occasion considers that from the control aspect of plating speed the concentration of preferably sulfuric acid copper is that the concentration of 6-9g/L, Rochelle salt is 70-90g/L.By the same token, the pH that plating is bathed is preferably 12-13, bathes temperature and is preferably 20-30 ℃.Bathe contained reducing agent as plating, for example use formaldehyde etc., its concentration can be decided to be 15-30cc/L.

At active material particle 7 are occasions of siliceous particle, and no matter this siliceous particle is which form among above-mentioned (1) (5), its average grain diameter (D ₅₀) 0.1-10 μ m preferably all, especially preferably 0.3-8 μ m most preferably is 0.8-5 μ m.That is to say that this active material particle is the minuteness particle (following this active material particle is called the small-particle diameter active material particle) of small particle diameter.When using the small-particle diameter active material particle, the more difficult active material particle that causes comes off from negative pole, the long lifetime of the negative pole possibility that becomes.More detailed saying, active material particle since when lithium is emitted in embedding with significant change in volume, therefore little by little controlled micro crystallization or micronizing.Result from that crackle takes place for this, the electrochemistry contact forfeiture of the active material particle of a part.This becomes as the important characteristic of secondary cell is the principal element that " charge " reduces.Therefore, by from beginning to use at negative pole the minuteness particle of small particle diameter originally, the further micronizing of the particle when suppressing to discharge and recharge improves charge.In addition, when the average grain diameter of small-particle diameter active material particle during, easily cause the oxidation of particle less than the lower limit of above-mentioned scope.And, such minuteness particle manufacturing cost height.The particle diameter of small-particle diameter active material particle is measured by laser diffraction and scattering method, electron microscope observation (SEM observation).

The small-particle diameter active material particle is because its surface area is big, and is therefore with particle (for example particle of the tens μ m) ratio of bigger particle diameter, easily oxidized.It is that the principal element that " irreversible capacity " increases reaches the principal element that " charging and discharging currents efficient " reduces as the important characteristic of secondary cell that active material particle is oxidized into same with " charge " of narration before.Specifically, when containing volume oxygen in the small-particle diameter active material particle, the lithium ion that embeds on the electrochemistry forms firm combining with oxygen atom, and lithium ion can not dissociated when discharge.Therefore, the small-particle diameter active material particle particle that need compare greater particle size is more strictly controlled oxygen concentration.Specifically, the concentration of the oxygen that the small-particle diameter active material particle contains is preferably less than 2.5 weight %, more preferably 1.5 weight % or following, more preferably 1 weight % or following.Relative with it, the particle of bigger particle diameter is because surface area is big, and therefore the control for oxidation does not need strictness like that.The concentration of the oxygen that the small-particle diameter active material particle contains is low more preferred more.Much less, most preferably do not contain aerobic fully, but in view of the manufacture method of small-particle diameter active material particle, the minimum of the oxygen concentration that can reach is about 0.005 weight % now.The oxygen concentration of small-particle diameter active material particle utilizes the eudiometry with burning of determination object sample to measure.

On the basis of oxygen concentration in small-particle diameter active material particle integral body less than above-mentioned value, the concentration of the most surperficial Si of this its particle of small-particle diameter active material particle preferably surpasses 1/2 with the ratio of oxygen concentration, more preferably 4/5 or more than, further preferred 10 or more than.The reduction of the increase of irreversible capacity and charging and discharging currents efficient is mainly by about the most surperficial oxygen concentration of small-particle diameter active material particle, and the result of inventor's investigation has distinguished this fact.Its reason is to be present in the easy and lithium reaction when secondary cell charge of the most surperficial oxygen, thereby to become the reason that makes the battery behavior deterioration.Therefore, stipulated the ratio of the concentration of the concentration of the most surperficial Si of particle and oxygen as described above.The surface oxygen concentration of small-particle diameter active material particle adopts and measures with the various surface state analytical equipments headed by x-ray photoelectron spectroscopy analytical equipment (ESCA) and the auger electron spectroscopic analysis device (AES) etc.

State in the use in addition, (1)-occasion of any method of (5) is all preferably in the condition of not sneaking into oxygen, for example make the small-particle diameter active material particle under inert gas atmosphere.

No matter the small-particle diameter active material particle is any of above-mentioned (1)-(5), and this small-particle diameter active material particle all adopts the breaking method of defined to reach the average grain diameter of above-mentioned scope.As breaking method, representational is dry type comminuting method and case of wet attrition method.In the dry type comminuting method, for example use aeropulverizer etc.On the other hand, in the case of wet attrition method, particle is scattered in has adopted in the pulverizing solvent of hexane and acetone and other organic solvent, use crushing mediums such as alumina bead and zirconium oxide bead to come sized particles.

By this crushing operation, the small-particle diameter active material particle is oxidized under the situation mostly.Therefore, preferably with small-particle diameter active material particle (the average grain diameter D of this particle behind the crushing operation ₅₀Reach 0.1-10 μ m) use the corrosive liquid corrosion, remove the oxide that is present in this particle surface.In view of the above, can easily make the oxygen concentration of small-particle diameter active material particle integral body and the most surperficial oxygen concentration of particle be above-mentioned value maybe this below value.As corrosive liquid, for example HF, buffering acid, NH ₄The aqueous solution of F, KOH, NaOH, ammonia or hydrazine etc.The degree of corrosion can be according to suitable controls such as the temperature of the kind of corrosive liquid and concentration, corrosive liquid, etching times.Can easily make the oxygen concentration of small-particle diameter active material particle integral body and the most surperficial oxygen concentration of particle in view of the above is in the above-mentioned scope.But in this operation, should not remove the oxide of particle surface fully.Its reason is because the particle of having removed oxide fully can be by abrupt oxidization in being exposed to atmosphere the time.Therefore, this operation is preferably adjusted the degree of corrosion, so that the oxide appropriateness is residual.Surface appropriateness residual the particle of oxide, even also can roughly keep the surface and the whole oxygen concentration of this particle after the corrosion after being exposed in the atmosphere.

For example, drop into the small-particle diameter active material particle among the HF to about concentration 1-50 weight %, by about 5-30 minute, making the most surperficial oxygen concentration of particle be reduced to desired horizontal at stirring at room liquid with the occasion of HF corrosion.Occasion with KOH or NaOH corrosion drops into the small-particle diameter active material particle in the aqueous solution to about concentration 1-40 weight %, get final product about 5-120 minute at stirring at room liquid.In occasion with ammonia corrosion, drop into the small-particle diameter active material particle in the aqueous solution to about concentration 1-20 weight %, get final product about 5-60 minute at stirring at room liquid.Using NH ₄The occasion of F corrosion drops into the small-particle diameter active material particle in the aqueous solution to about concentration 1-50 weight %, get final product about 5-60 minute at stirring at room liquid.In occasion with the hydrazine corrosion, drop into the small-particle diameter active material particle in the aqueous solution to about concentration 1-50 weight %, get final product about 5-60 minute at stirring at room liquid.

The negative pole that contains the small-particle diameter active material particle of above explanation, even repeated charge, the micronized influence of the miniaturization of active material particle is also little.Its result, efficiency for charge-discharge is improved, and irreversible capacity reduces the charge raising.In addition, by reducing the oxygen content in the small-particle diameter active material particle, irreversible capacity also can reduce, and efficiency for charge-discharge improves the charge raising.

The surface of small-particle diameter active material particle also can be covered with metallic film.Because of the lining of metallic film, the oxidation of small-particle diameter active material particle is suppressed, and has prevented the increase of irreversible capacity and the decline of charging and discharging currents efficient effectively.In addition, electronic conductivity improves, and charge further is enhanced.

From the viewpoint of the oxidation that suppresses the small-particle diameter active material particle effectively and make Li and viewpoint that the reaction of Si is carried out expeditiously considers that the thickness of metallic film is preferably 0.005-4 μ m, is preferably 0.05-0.5 μ m especially.The thickness of metallic film is for example measured by ESCA or AES.

As the metal that constitutes metallic film, preferably use lithium to form the low metal of ability.For example use Ni, Cu, Co, Fe, Ag or Au as such metal, special in anti-oxidation viewpoint, preferably use Ni, Co, Ag or Au.These metals can use with simple substance respectively, or use as two or more alloys that form of combination.

In small-particle diameter active material particle with the metallic film lining, the oxygen concentration of the boundary portion of metallic film and small-particle diameter active material particle, according to above-mentioned illustrating about the small-particle diameter active material particle, the concentration of Si surpasses 1/2 of oxygen concentration.The boundary portion of metallic film and small-particle diameter active material particle thinks to utilize AES to analyze the small-particle diameter active material particle that is covered with metallic film, and the concentration of metal that constitutes metallic film reaches minimizing part.

Consider that from improving the words that the most surperficial oxygen concentration of metallic film is low are more satisfactory with the conductivity aspect of the small-particle diameter active material particle of metallic film lining.

Small-particle diameter active material particle with the metallic film lining is preferably made in the following method.At first, according to the manufacture method of previously described small-particle diameter active material particle, after employing dry type comminuting method or case of wet attrition method are ground into the size of regulation with particle, be present in the oxide of this particle surface by erosion removal.Fully the particle after the washing corrosion then is supplied to the chemical plating operation, at particle surface coated metal film.Before chemical plating, also can implement common photosensitive processing and activation processing to particle surface.The condition of chemical plating is suitably selected according to the metal of plating is suitable.For example, form, list following bath and form as the bath of the occasion of plating Ni.Under this occasion, bathe temperature and be decided to be about 40-60 ℃, the pH of bath is decided to be about 4-6.The plating time is decided to be the 0.5-50 branch.

NiSO ₄·6H ₂O 15-35g/L

NaH ₂PO ₂·H ₂O 10-30g/L

Na ₃C ₆H ₅O ₇ 15-35g/L

NaC ₃H ₅O ₂ 5-15g/L

The metallic film that forms on small-particle diameter active material surface is incomplete coated particle integral body also.For example a large amount of fine pore that extends for the thickness direction at metallic film is present in this metallic film, and this metallic film also can roughly general equably coated particle surface.Arrive small-particle diameter active material particle inside by fine pore electrolyte thus, therefore can cause the original electrochemical reaction that shows of siliceous particle conscientiously.Perhaps, metallic film also can be covered into island with particle.

Secondly, the preferred manufacture method of negative pole of the present invention is described.In this manufacture method, at first prepare to be coated in the slurry on collector body surface.Slurry for example contains particle, adhesive and the retarder thinner of active material particle, conductive carbon material.Among these compositions, about the particle of active material particle and conductive carbon material according to previously described the same.As adhesive, use Kynoar (PVDF), polyethylene (PE), ethylene propylene diene monomer (EPDM) etc.Use N-methyl pyrrolidone, cyclohexane etc. as retarder thinner.

The amount of the active material particle in the slurry is preferably about 14-40 weight %.The amount of the particle of conductive carbon material is preferably about 0.4-4 weight %.The amount of adhesive is preferably 0.4-4 weight % in addition, and the amount of retarder thinner is preferably about 60-85 weight %.

This slurry coating is formed active material layer on the collector body surface.Collector body can be made in advance, perhaps can be used as an online manufacturing of operation in the manufacturing process of negative pole of the present invention.Collector body is the occasion of online manufacturing, preferably separates out manufacturing by electrolysis.Slurry reaches the amount of 1-3 about doubly of the thickness of the active material structure that finally obtains to the thickness that the amount that applies on the collector body is preferably dried active material layer.After the dried coating film of slurry forms active material layer, during the plating that the collector body that has formed this active material layer is immersed in the low conductive material of the formation ability that contains lithium compound is bathed, under the sort of state, on active material layer, carry out the plating of this conductive material, form surface-coated layer.By using this method, can in surface-coated layer, easily form a large amount of fine pores.Details is the same according to previous narration, and the surface of active material layer 3 becomes trickle concaveconvex shape, becomes the state that coating avtive spot of easily growing up and the site that is difficult for growing up mix existence.When the active material layer 3 enterprising electroplatings at such state, the growth of coating takes place irregular, and the particle of the constituent material of surface-coated layer 4 becomes to grow up to the polycrystalline shape.When the growth of crystal is down carried out, when adjacent crystal is touched, form hole in that part.As the condition of electroplating, for example use the occasion of metallic copper as conductive material, when using copper sulphate to be solution, the concentration of regulation copper be the concentration of 30-100g/L, sulfuric acid be the concentration of 50-200g/L, chlorine be 30ppm or following, liquid temperature for 30-80 ℃, current density be 1-100A/dm ²Get final product.When using this electrolytic condition, can easily form its part and enter into the surface-coated layer of active material layer or reach the surface-coated layer of collector body and even be impregnated into the surface-coated layer of active material layer integral body.As other electrolytic condition, also can use cupric pyrophosphate is solution.In this occasion, the concentration of regulation copper be the concentration of 2-50g/L, potassium pyrophosphate be 100-700g/L, liquid temperature for 30-60 ℃, pH be that 8-12, current density are 1-10A/dm ²Get final product.

After having formed surface-coated layer on the active material layer, can carry out press process to active material layer as described above together with surface-coated layer.Thus with the active material layer densificationization.By densificationization, constitute the space between the particle of the conductive material landfill active material particle of surface-coated layer and conductive carbon material, become the state that the particle of active material particle and conductive carbon material disperses.In addition, these particles and surface-coated layer adhere to, and pay electronic conductivity.And appropriateness is adjusted the degree of the hole be present in active material layer, takes off expansion that embedding active material particle lithium causes because of embedding and shrinks the stress that caused by lax.Consider from the viewpoint that obtains sufficient electronic conductivity, the degree that the densificationization of press process is carried out preferably make the thickness summation of active material layer after the press process and surface-coated layer reach 90% before the press process or following, preferably reach 80% or below.Press process for example can be used roll squeezer.

In this manufacture method, also can be before the enterprising electroplating of active material layer, this active material layer of press process (, this press process being called preceding press process) in order to distinguish mutually with the press process of previous narration.By carrying out preceding press process, can prevent peeling off of active material layer and collector body, can also prevent that active material particle from exposing at surface-coated laminar surface.Its result can prevent to result from the deterioration of cycle life of the battery that comes off of active material particle.As the condition of preceding press process, the thickness of the active material layer before the thickness of the active material layer before preferably making after the press process reaches before the press process 95% or below, reach 90% or following such condition especially.

Also have in this manufacture method, plating has been used in the formation of surface-coated layer, but generation also can use sputtering method, chemical vapor coating method or physical vapor vapour deposition method.In addition, surface-coated layer also can form by the rolling of conductivity paper tinsel.For example can form by rolling or the rolling of Markite paper tinsel of the rolling of metal forming or net metal paper tinsel.In the occasion of these methods of use, the condition of the press process of the previous narration of control forms fine pore in surface-coated layer.

Another preferred manufacture method of negative pole of the present invention below is described.In this manufacture method, use and disperse the plating method.In disperseing the plating method, the plating of preparing to be suspended with active material particle and containing the low conductive material of the formation ability of lithium compound is bathed.The amount of the active material particle during this plating is bathed is considered from the aspect that the active material particle group that might make abundant amount is gone into to the active material structure, preferably 200-600g/L, especially preferably 400-600g/L.In addition, the concentration of the conductive material that the formation ability of the lithium compound during plating is bathed is low, for example use metallic copper as conductive material, use the occasion of copper sulphate as the copper source, control aspect from plating speed, consider that with the aspect of the surface-coated layer of the thickness that can form the active material layer that can fully keep active material particle and constituted the concentration of preferably copper is 30-100g/L, the concentration of sulfuric acid is 50-200g/L, the concentration of chlorine is 300ppm or following, the concentration of cresol sulfonic acid is 40-100g/L, the concentration of gelatin is 1-3g/L, the concentration of Beta Naphthol 99MIN is 0.5-2g/L.

Secondly, in plating is bathed, flood collector body, under the sort of state, begin to electroplate.Current density in the electrolysis is considered preferably 1-15A/dm from control plating speed aspect ²The plating bath temperature can be the room temperature of 20 ℃ of front and back.By this plating, the metal during plating is bathed is reduced, and when forming surface-coated layer, forms by the active material layer of surface-coated layer lining on the collector body surface.In order evenly to form active material layer, while can stir plating bath carrying out electrolysis.

About the collector body that uses in the present invention according to previously described the same, but the also preferred collector body that uses the multicellular metal foil by following narration to constitute.This multicellular metal foil (the following metal forming that only is called) has a large amount of minute apertures.In this metal forming, exist with its minute aperture that connects along its thickness direction and inaccessible halfway minute aperture both.Among both, the said minute aperture of the present invention is meant the minute aperture that metal forming is connected at thickness direction., this is not to get rid of the metal forming that exists in inaccessible minute aperture midway in the present invention.In addition, do not mean preferred such metal forming yet.

When this metal forming is used as collector body, fully guaranteed by this collector body electrolyte flow path, therefore the capacity of nonaqueous electrolytic solution secondary battery further improves, and has prevented more effectively that also active material from coming off from electrode because of embedding removal lithium embedded, and cycle characteristics improves.

The diameter of the minute aperture in the metal forming is 0.01-200 μ m preferably, is more preferably 0.05-50 μ m, further 0.1-10 μ m preferably.When the diameter of minute aperture during, often can not fully guarantee flowing of nonaqueous electrolytic solution less than 0.01 μ m.When the diameter of minute aperture surpasses 200 μ m, because of with the relation of the thickness of metal forming described later, the intensity of metal forming might reduce.In addition, active material takes off embedding because of the embedding of lithium easily and comes off, and the cycle characteristics of nonaqueous electrolytic solution secondary battery might reduce.Also have, in this metal forming, do not need whole minute apertures of its perforation are all had the diameter of above-mentioned scope, allow the minute aperture of the above-mentioned extraneous diameter that in the manufacturing process of metal forming, produces inevitably that has only a few.

No matter get which position of metal forming, have above-mentioned diameter minute aperture exist density at 1cm ²Area in all preferred 5-10000, more preferably 10-5000, further preferred 100-2000.Exist density less than 1/1cm when minute aperture ²The time, the nonaqueous electrolytic solution that can not fully measure to active substance delivery often.Exist density to surpass 10000/cm ²The time, to fasten with the pass of the higher limit of the diameter of above-mentioned minute aperture, the intensity of metal forming might reduce.

The diameter of minute aperture and exist the assay method of density as follows.Dorsal part in the darkroom from metal forming sees through light, takes the photo of metal forming under the sort of state.Resolve this photo by image, obtain the diameter of minute aperture and have density.

The thickness of metal forming is 1-100 μ m preferably, is more preferably 2-20 μ m, further 3-10 μ m preferably.The thickness of metal forming is less than the occasion of 1 μ m, though because energy density improves and preferred, mechanical strength is insufficient, might make difficulty in addition.When thickness surpasses 100 μ m, be not easy to form the minute aperture of perforation, might be difficult to improve energy density and become difficult.In addition, also hinder electrolyte to flow smoothly.

Metal forming can be made of various metal materials.For example can be made into the metal forming that contains at least a kind of metal among Cu, Ni, Co, Fe, Cr, Sn, Zn, In, Ag and the Au.That is to say, can constitute metal forming by the simple substance of these metals or these metals two kinds or more kinds of alloy or the material that except that these metals, also contains other elements.From considering especially preferably to constitute by Cu, Ni, Co, Fe, Cr, Au with the reactive low aspect of lithium.

Secondly about the preferred manufacture method of metal forming with reference to Fig. 5 (a)-Fig. 5 (f) explanation.At first shown in Fig. 5 (a), prepare foils 11.The material of foils 11 is not particularly limited.Foils 11 is conductivity preferably.This occasion, if conductivity is arranged, then foils 11 can not be metal., when using metal foils 11, its advantage is can be with foils 11 fusing foliations with recycling after making metal forming.Use the occasion of metal foils 11, preferably contain at least a kind of metal among Cu, Ni, Co, Fe, Cr, Sn, Zn, In, Ag, Au, Al and the Ti and constitute foils 11.Foils 11 is owing to be to use as the supporter of making metal forming, therefore preferably has not produce the intensity of crooking etc. in manufacturing process.Therefore, foils 11 preferred its thickness are about 10-50 μ m.

Secondly shown in Fig. 5 (b), adopt the gimmick lining lining body 12 of regulation in the one side of foils 11.Preferably before lining, foils 11 implemented pre-treatments such as acid elutions, clean its surface.Lining body 12 is used to make the electronic conductivity of the formation face of metal forming to be uneven state, thereby forms a large amount of minute apertures in metal forming.Lining body 12 its thickness when forming preferably reaches 0.001-1 μ m, especially preferably reaches 0.002-0.5 μ m, further preferably reaches 0.005-0.2 μ m.This is because when being set at the thickness of this degree, lining body 12 can be discontinuously the be covered surface of foils 11, island ground for example.Form lining body 12 discontinuously, from easily forming diameter and existing the minute aperture aspect of density to consider it is favourable with previous narration.In Fig. 5 (b), for helping to understand, the size of lining body 12 is described with being highlighted.

Lining body 12 is made of the material different with the constituent material of metal forming.Thus in stripping process described later, can be from foils 11 head and the tail stripping metal paper tinsel well.The body 12 that particularly is covered is materials different with the constituent material of metal forming, and preferably contains at least a kind of element among Cu, Ni, Co, Mn, Fe, Cr, Sn, Zn, In, Ag, Au, C, Al, Si, Ti and the Pd and constitute.

The formation method of lining body 12 is not particularly limited.For example fastening optional formation method of selecting lining body 12 with the pass of the formation method of metal forming described later.Specifically, in the occasion that forms metal forming with plating, also with electroplating formation, this considers more satisfactory from making aspects such as efficient lining body 12.Adopt additive method, for example chemical plating, sputtering method, physical vapor vapour deposition method (PVD), chemical vapor coating method (CVD), sol-gal process or ion implantation also can form lining body 12 in addition.

Adopting the occasion of electroplating formation lining body 12, select suitable plating to bathe and the plating condition according to the constituent material of lining body 12.For example in the occasion that constitutes lining body 12 by tin, as plating bathe can use have a following composition or the fluoboric acid tin bath.Preferably about 15-30 ℃, current density is 0.5-10A/dm preferably for the bath temperature of using the occasion that this plating bathes ²About.

SnSO ₄ 30-70g/L

H ₂SO ₄ 60-150g/L

Cresol sulfonic acid 70-100g/L

The same according to previous narration, lining body 12 are used to make the electronic conductivity of the formation face of metal forming to be uneven state.If therefore the electronic conductivity of the electronic conductivity of the constituent material of lining body 12 and foils 11 is different greatly, then by forming lining body 12, the electronic conductivity of the formation face of metal forming becomes uneven state immediately.For example use the situation of carbon as the constituent material of lining body 12.On the other hand, constituent material as lining body 12, use has with the material of the electronic conductivity of foils 11 same degree, for example with the occasion of the various metal materials headed by tin etc., by the formation of lining body 12, the electronic conductivity of the formation face of metal forming can not become uneven state immediately.So in the occasion that is made of lining body 12 such material, the foils 11 that preferably will form lining body 12 is exposed in oxygen-containing atmosphere, for example atmosphere under drying regime.Make surface (and foils 11 the expose face) oxidation (with reference to Fig. 5 (c)) of lining body 12 thus.By this operation, the electronic conductivity of the formation face of metal forming becomes uneven state.When under this state, carrying out plating described later, create a difference on the surface of lining body 12 and the face electrolysis speed of exposing of foils 11, can easily form diameter with previous narration and the minute aperture that has density.The degree of oxidation is not very critical in the present invention.The foils 11 that for example will form lining body 12 is placed about 10-30 minute promptly enough in atmosphere, this distinguishes by the inventor's investigation.Especially forcibly it is also harmless that oxidation has formed the foils 11 of lining body 12.

When the foils 11 that will form lining body 12 was exposed in the oxygen-containing atmosphere, the reason that makes it to be drying regime was in order to carry out oxidation expeditiously.For example by electroplate forming the occasion of lining body 12, from plating bathe mention foils 11 after, use drier etc. to make it dry, then in atmosphere, place the stipulated time to get final product.As the formation method of lining body 12 occasion in the dry process of using sputtering method and various vapour deposition methods etc., do not need drying process, lining body 12 is placed in the atmosphere with forming the back former states and gets final product.

After making 12 oxidations of lining body, shown in Fig. 5 (d), to applying remover 13 above it.Remover 13 is used at stripping process described later from foils 11 head and the tail stripping metal paper tinsel well.As the remover 13 preferred organic compounds that use, especially preferably use nitrogen-containing compound or sulfur-containing compound.As nitrogen-containing compound, for example preferably use BTA (BTA), carboxyl benzotriazole (CBTA), tolyl-triazole (TTA), N ', N '-two (BTA ylmethyl) urea (BTD-U) and 3-amino-1H-1,2, three azole compounds of 4-triazole (ATA) etc.As sulfur-containing compound, list mercaptobenzothiazoler (MBT), sulfo-cyanuric acid (TCA) and 2-benzimidazole mercaptan (BIT) etc.The operation that applies remover after all in stripping process described later from foils 11 stripping metal paper tinsel and carrying out successfully.Even therefore save the metal forming that this operation also can form porous.

Secondly shown in Fig. 5 (e), on the basis that has applied remover 13, make the constituent material electrolysis of metal forming form metal forming 14 by plating.In formed metal forming 14, form the minute aperture of the diameter of a large amount of previous narrations with the density that exists of previous narration.In Fig. 5 (e), depict as in the position on summit of lining body 12 and formed minute aperture, but this is for convenience's sake, in fact may not form minute aperture at the vertex position of lining body 12.Plating is bathed and the plating condition is selected according to the constituent material of metal forming is suitable.For example in the occasion that is made of metal forming 14 Ni, bath can use the watt with following composition to bathe or the sulfamic acid bath as plating.Preferably about 40-70 ℃, current density is 0.5-20A/dm preferably for the bath temperature of using the occasion that these platings bathe ²About.

NiSO ₄·6H ₂O 150-300g/L

NiCl ₂·6H ₂O 30-60g/L

H ₃BO ₃ 30-40g/L

Can easily control the diameter of minute aperture if the method more than adopting is made metal forming 14 and have density.It is the reasons are as follows: above-mentioned manufacture method is owing to the surface electrical precipitating metal paper tinsel of the foils of always changing in new face, i.e. manufacturing at every turn, and it is constant therefore always keeping the state of this face.

Resulting metal forming 14 approaches according to the same its thickness of previous narration, therefore with improper under the most situation of it individual processing.So, preferred not from foils 11 stripping metal paper tinsels 14 till being over for the processing of metal forming 14 defineds (for example the formation of active material layer described later etc.).After the processing of regulation is over, shown in Fig. 5 (f), get final product from foils 11 stripping metal paper tinsels 14.Between foils 11 and metal forming 14 according to previous narration equally applied remover 13, therefore can carry out metal forming 14 peeling off well by head and the tail from foils 11.Fig. 5 (f) expresses lining body 12 and remains in the state of foils side, but lining body 12 to remain in the foils side, still remain in the metal forming side be miscellaneous.About remover too.No matter be which occasion,, therefore can not cause bad influence to metal forming because the consumption of lining body and remover is little by little.

Replace above method, metal forming 14 adopts the method narrated below (below be called other methods 1) also can make.At first prepare to contain the coating liquid, for example paste of the particle of material with carbon element etc.For example can use acetylene carbon black etc. as material with carbon element.From can easily forming diameter and existing the aspect of the minute aperture of density to consider the average grain diameter D of material with carbon element with previous narration ₅₀(by laser diffraction and scattering method and scanning electron microscopic observation and be used for measuring) be preferably 2-200nm, be preferably about 10-100nm especially.This coating liquid is coated on the supporter of regulation.Coating thickness is preferably 0.001-1 μ m, is preferably about 0.05-0.5 μ m especially.Then on filming, make the constituent material electrolysis of metal forming, form metal forming by plating.The condition of electroplating can be decided to be identical with plating condition in the method for before having narrated.

As supporter, typically list the foils of previous narration, but be not limited thereto.

After metal forming formed, this metal forming can be peeled off from supporter, perhaps also can not peel off to present former state.For example in the manufacturing of negative electrode for nonaqueous secondary battery described later, be suitable for the occasion of this method, do not need the stripping metal paper tinsel.In the occasion of stripping metal paper tinsel, consider that from making the good viewpoint of fissility preferably apply remover on the basis that has been coated with the paste that contains material with carbon element, electrolysis goes out metal forming in the above on the contrary.Can use the identical remover of remover that uses in the method with narration formerly as remover.

The method that replaces other methods 1 to adopt narrating below (below be called other methods 2) also can form metal forming.In other methods 2, at first preparation contains the plating bath of the constituent material of metal forming.For example in the occasion that is made of metal forming Ni, watt bath of preparing before to have narrated or sulfamic acid are bathed and are got final product.The particle that adds material with carbon element in this plating is bathed makes it to suspend.Can use and the identical material with carbon element of material with carbon element that in other methods 1, uses as material with carbon element.It is identical with other methods 1 that the particle diameter of material with carbon element also can be decided to be.The amount of the material with carbon element that suspends in plating is bathed from can easily forming the diameter with previous narration and existing the aspect of the minute aperture of density to consider, is preferably 0.5-50g/L, is preferably about 1-10g/L especially.

Under the state that the bath of stirring plating suspends material with carbon element, the supporter of defined is electroplated, the constituent material electrolysis of metal forming is gone out, obtain metal forming 14.Can use and the identical supporter that in other methods 1, uses as supporter.The processing of the metal forming after forming about metal forming also can be decided to be identical with other methods 1.Moreover, can use the supporter that has applied remover as requested.Can carry out peeling off of metal forming well by head and the tail thus.

Used the manufacture method of negative pole of multicellular metal foil 14 as follows.Negative pole can utilize the manufacture method manufacturing of the metal forming of previous narration.For example at first make metal forming according to the method shown in Fig. 5 (a)-(e).Secondly, under the state of foils stripping metal paper tinsel, do not forming active material layer in metal forming.Active material layer for example forms by the paste that coating contains the particle of the particle of active material and conductive material.The plating that the metal forming that has formed active material layer is immersed in the low conductive material of the formation ability that contains lithium compound carries out the plating of this conductive material in bathing on active material layer under the sort of state, forms surface-coated layer.Last shown in Fig. 5 (f), by obtaining negative pole from foils stripping metal paper tinsel.

The negative pole of the present invention that obtains like this uses with known positive pole, dividing plate, non-aqueous electrolyte and makes nonaqueous electrolytic solution secondary battery.Anodal preparation method is, positive active material and conductive agent as required and adhesive are suspended in the appropriate solvent, make anode mixture, this anode mixture is coated on the collector body after the drying, by rolling system, compacting, shearing again, blanking and obtain.Use known in the past positive active materials such as lithium nickel composite oxide, complex Li-Mn-oxide, lithium cobalt composite oxide as positive active material.As dividing plate, preferably use synthetic resin system nonwoven fabrics, polyethylene or polypropylene porous film etc.As the occasion of lithium secondary battery, nonaqueous electrolytic solution is by having dissolved in organic solvent as the solution composition of supporting electrolytical lithium salts.Can list for example LiClO as lithium salts ₄, LiAlCl ₄, LiPF ₆, LiAsF ₆, LiSbF ₆, LiSCN, LiCl, LiBr, LiI, LiCF ₃SO ₃, LiC ₄F ₉SO ₃Deng.

The present invention is not limited by above-mentioned embodiment.For example as collector body, can use the punch metal with a large amount of perforates or the metal foam body of porous metals or nickel foam etc.In the occasion of using punch metal or porous metals, the area of perforate is 0.0001-4mm preferably ², 0.002-1mm especially preferably ²About.In the occasion of using punch metal or porous metals, preferentially form active material layer in the part of perforate, form surface-coated layer on the surface of formed active material layer and the surface of punch metal or porous metals.On the other hand, the occasion using metal foam body is full of by active material layer in the hole of foams, forms surface-coated layer on the surface of this active material layer and the surface of metal foam body.

In addition, Fig. 2-cross-section photograph picture shown in Figure 4 expresses the state that has only formed active material structure 5 in the one side of collector body 2, but active material structure also can form on the two sides of collector body.

Illustrate in greater detail the present invention by the following examples., scope of the present invention is by such embodiment restriction.Only otherwise special declaration, " % " means " weight % " in the following example.

[embodiment 1-1]

(1) manufacturing of active material particle

1400 ℃ the motlten metal that will contain silicon 90%, nickel 10% pours in the mold made of copper, obtains by the ingot casting of the silicon-nickel alloy of chilling.This ingot casting is crushed and screened, obtain silicon-nickel alloy particle of particle diameter 0.1-10 μ m.Mix this silicon-nickel alloy particle 80% and nickel particles (particle diameter 30 μ m) 20%, adopt vertical ball mill to carry out the mixing and the pulverizing of these particles simultaneously.Obtain the stuff and other stuff that silicon-nickel alloy and nickel are mixed equably thus.The maximum particle diameter of this stuff and other stuff is 1 μ m, D ₅₀Value is 0.8 μ m.

(2) preparation of slurry

The slurry that has prepared following composition.

The stuff and other stuff 16% that in above-mentioned (1), obtains

Acetylene carbon black (particle diameter 0.1 μ m) 2%

Adhesive (Kynoar) 2%

Retarder thinner (N-methyl pyrrolidone) 80%

(3) formation of active material layer

Prepared slurry coating is made it dry on the Copper Foil of thickness 35 μ m.The thickness of dried active material layer is 60 μ m.Dried active material layer is carried out preceding press process.

(4) formation of surface-coated layer

The Copper Foil that has formed active material layer is immersed in the plating bath with following composition, at the enterprising electroplating of active material layer.

Nickel 50g/L

Sulfuric acid 60g/L

Bathe 40 ℃ of temperature

After forming surface-coated layer, mention Copper Foil, thereby then reinstate roll-in system active substance for processing layer densificationization together with surface-coated layer one from the plating bath.The thickness of the active material structure that obtains like this, the result of electron microscope observation is 23 μ m.In addition, chemico-analytic result, the amount of the active material particle in the active material structure is 40%, the amount of acetylene carbon black is 5%.Judge that with electron microscope observation fine pore has or not existence for the negative pole that obtains like this, the result has confirmed its existence.

[embodiment 1-2 to 1-4]

Except using the particle of the composition shown in the table 1-1, similarly obtain negative pole with embodiment 1-1 as active material particle.About the negative pole that obtains, the same method of employing and embodiment 1-1 judges that fine pore has or not existence, and the result has confirmed its existence.

[embodiment 1-5]

On the Copper Foil of thickness 35 μ m, implement the nickel coating of 2 μ m as collector body.On this nickel coating, active material layer and surface-coated layer have similarly been formed with embodiment 1-1.Wherein used the particle of the composition shown in the table 1-1 as the contained active material particle of active material layer.Obtain negative pole as described above.About the negative pole that obtains, the same method of employing and embodiment 1-1 judges that fine pore has or not existence, and the result has confirmed its existence.

[embodiment 1-6]

Used the nickel foam of thick 400 μ m as collector body.The average diameter of the bubble in these foams is 20 μ m.Except the active material particle that contains the composition shown in the table 1-1, preparation and the same slurry of embodiment 1-1 penetrate in the foams this slurry.These foams are immersed in the plating that has and use bathe in the plating bath of same composition in embodiment 1-1, electroplate and obtain negative pole.About the negative pole that obtains, the same method of employing and embodiment 1-1 judges that fine pore has or not existence, and the result has confirmed its existence.

[embodiment 1-7]

The copper porous metals of thick 40 μ m have been used as collector body.The area of each perforate of these porous metals is 0.01mm ²Except the active material particle that contains the composition shown in the table 1-1, preparation and the same slurry of embodiment 1-1 penetrate in the porous metals this slurry.These porous metals are immersed in the plating that has and use bathe in the plating bath of same composition in embodiment 1-1, electroplate and obtain negative pole.About the negative pole that obtains, the same method of employing and embodiment 1-1 judges that fine pore has or not existence, and the result has confirmed its existence.

[comparative example 1-1]

The powdered graphite of mixing particle diameter 10 μ m, adhesive (PVDF) and retarder thinner (N-methyl pyrrolidone) are made slurry, are coated on the Copper Foil of thickness 30 μ m, make it dry back press process and obtain negative pole.The thickness that graphite after the press process is filmed is 20 μ m.

[comparative example 1-2]

Except the silicon particle that replaces powdered graphite use particle diameter 5 μ m, similarly obtain negative pole with comparative example 1-1.

[performance evaluation]

The negative pole that use obtains in embodiment and comparative example has been made nonaqueous electrolytic solution secondary battery according to following method.Weight capacity density, the efficiency for charge-discharge of 10 circulation times and the capacity sustainment rate of 50 circulation times when having measured irreversible capacity, charging with following method.Following table 1-1 expresses these results.

[making of nonaqueous electrolytic solution secondary battery]

As electrode being used lithium metal, use the above-mentioned negative pole that obtains as active electrode, making the two poles of the earth is media and in opposite directions with the dividing plate.And, use LiPF as nonaqueous electrolytic solution ₆The mixed solution of/ethylene carbonate and diethyl carbonate (1: 1 Capacity Ratio) adopts usual way to make nonaqueous electrolytic solution secondary battery.

[irreversible capacity]

The capacity in the active material can not be discharged, be remained in irreversible capacity (%)=(the first discharge capacity of 1-/primary charging capacity) * 100 promptly though expression has been charged.

[capacity density]

Represent first discharge capacity.Unit is mAh/g.

[efficiency for charge-discharges of 10 circulation times]

Charging capacity * 100 of discharge capacity/10th circulation of the efficiency for charge-discharge of 10 circulation times (%)=10th circulation

[50 circulation volume sustainment rates]

Discharge capacity/maximum discharge capacity * 100 of 50 circulation volume sustainment rates (%)=50th circulation

Table 1-1

		Active material structure						Irreversible capacity (%)	Capacity density (mAh/g)	10 circulation time efficiency for charge-discharges (%)	50 circulation time capacity sustainment rates (%)
		Active material structure										Surface-coated layer		Active material layer
		Thickness (μ m)	Material	Thickness (μ m)	Active material particle							Surface-coated layer		Active material layer
					Active material particle							Particle diameter D ₅₀ (μm)	Content in the active material structure (wt%)	Material
					Embodiment	1-1	3					Particle diameter D ₅₀ (μm)	Content in the active material structure (wt%)	Material	Ni	20	0.8	40	[Si90/Ni10] (casting) 80/Ni20	4	3100	99.9	98
1-2	3	Ni	20	0.8		1-1	3	40	[Si90/Ni10] (casting) 80/Cu20	5	3100	99.9	98		Ni	20	0.8	40	[Si90/Ni10] (casting) 80/Ni20	4	3100	99.9	98
1-2	3	Ni	20	0.8		1-3	3	40	[Si90/Ni10] (casting) 80/Cu20	5	3100	99.9	98	Ni	20	0.8	40	[Si80/Cu20] (casting) 80/Ni20	4	2800	99.9	97
1-4	3	Ni	20	0.8		1-3	3	40	[Si80/Cu20] (casting) 80/Cu20	5	2800	99.9	96	Ni	20	0.8	40	[Si80/Cu20] (casting) 80/Ni20	4	2800	99.9	97
1-4	3	Ni	20	0.8		1-5	3	40	[Si80/Cu20] (casting) 80/Cu20	5	2800	99.9	96	Ni	20	0.8	40	[Si80/Ni20] (casting) 80/Ni20	4	2800	99.9	99
1-6	3	Ni	20	0.8		1-5	3	40	[Si80/Ni20] (casting) 80/Ni20	4	2800	99.9	99	Ni	20	0.8	40	[Si80/Ni20] (casting) 80/Ni20	4	2800	99.9	99
1-6	3	Ni	20	0.8		1-7	3	40	[Si80/Ni20] (casting) 80/Ni20	4	2800	99.9	99	Ni	20	0.8	40	[Si80/Ni20] (casting) 80/Ni20	4	2800	99.9	99
Comparative example	1-1	---				1-7	3	10	80	Graphite	10	310	99.7	Ni	20	0.8	40	[Si80/Ni20] (casting) 80/Ni20	4	2800	99.9	99	100
	1-1	---			1-2	---			80	Graphite	10	310	99.7	5	80	Si is only arranged	60	2000	85.0	7			100

Distinguish clearly that by the result shown in the table 1-1 used the secondary cell of the negative pole that obtains in each embodiment, with the secondary cell ratio of the negative pole that has used comparative example, irreversible capacity is low, the capacity density height, efficiency for charge-discharge and capacity sustainment rate are also high.Though in table, do not express, the cross section of the negative pole that electron microscope observation obtains in embodiment 1-1 to 1-7, the result has structure shown in Figure 2.

[embodiment 2-1]

(1) preparation of slurry

The slurry that has prepared following composition.

Tin particle (particle diameter D ₅₀Be worth 2 μ m) 16%

Acetylene carbon black (particle diameter 0.1 μ m) 2%

Adhesive (Kynoar) 2%

Retarder thinner (N-methyl pyrrolidone) 80%

The formation of (2) filming

With prepared slurry coating on the Copper Foil of thickness 30 μ m and make it dry.The thickness of dried coating is 60 μ m.

(3) formation of coating

Be immersed in the plating bath with following composition, having formed the Copper Foil of filming at the enterprising electroplating of filming.

Copper 50g/L

Sulfuric acid 60g/L

Bathe 40 ℃ of temperature

After forming coating, mention Copper Foil, process the densificationization of filming thereby then reinstate roll-in system together with coating one from the plating bath.The thickness of the coating that obtains like this, the result of electron microscope observation is 20 μ m.In addition, chemico-analytic result, the amount of the tin particle in the coating is 70%, the amount of acetylene carbon black is 5%.

[embodiment 2-2 and 2-3]

Except form coating by nickel (embodiment 2-2), brill (embodiment 2-3), similarly obtained negative pole with embodiment 2-1.

[embodiment 2-4]

Periphery to the cylinder made of copper of high speed rotating penetrates 1000 ℃ the motlten metal that contains tin 60% bronze medal 40%.The rotating speed of cylinder is 1000rpm.Emitted motlten metal chilling on cylinder becomes the tin-copper alloy strip.The cooling rate of this moment is 10 ³More than the K/sec.This strip is crushed and screened, use the particle of particle diameter 0.1-10 μ m then.Except using this alloy particle, similarly obtained negative pole with embodiment 2-1.

[embodiment 2-5 and 2-6]

Except the tin-copper alloy particle that uses the composition shown in the table 2-1, similarly obtained negative pole with embodiment 2-4.

[embodiment 2-7 and 2-8]

Except the tin-nickel alloy particle that uses the composition shown in the table 2-1, similarly obtained negative pole with embodiment 2-4.

[embodiment 2-9 and 2-10]

Except the tin-copper-nickel alloy particle that uses the composition shown in the table 2-1, similarly obtained negative pole with embodiment 2-4.

[embodiment 2-11 and 2-16]

Except the tin that use to adopt the composition shown in the table 2-1 that quench obtains is the ternary alloy three-partalloy particle, similarly obtained negative pole with embodiment 2-4.

[embodiment 2-17]

Mix tin particle (particle diameter 30 μ m) 90% and copper particle (particle diameter 30 μ m) 10%, adopt vertical ball mill to carry out the mixing and the pulverizing of these particles simultaneously.Obtain the particle diameter 0.1-10 μ m (D that tin and copper are mixed equably thus ₅₀Be worth 2 μ m) stuff and other stuff.Except using this stuff and other stuff, similarly obtained negative pole with embodiment 2-1.

[embodiment 2-18 to 2-31]

Except the tin-copper stuff and other stuff of composition shown in the use table 2-2 and particle diameter and make the thickness of coating and the content of the stuff and other stuff in the coating for the value shown in this table, similarly obtained negative pole with embodiment 2-17.

[embodiment 2-32 to 2-39]

Except the tin of the composition shown in the use table 2-2 is stuff and other stuff, similarly obtained negative pole with embodiment 2-17

[embodiment 2-40]

Side face to the cylinder made of copper of high speed rotating penetrates 1000 ℃ the motlten metal that contains tin 75% bronze medal 25%.The rotating speed of cylinder is 1000rpm.Emitted motlten metal chilling on cylinder becomes the tin-copper alloy strip.The cooling rate of this moment is 10 ³More than the K/sec.This strip is crushed and screened, use the alloy particle of particle diameter 0.1-10 μ m then.This alloy particle 99% and silver particles (particle diameter 30 μ m) 1% are mixed, adopt vertical ball mill to carry out the mixing and the pulverizing of these particles simultaneously.Obtain tin-copper alloy and the silver-colored particle diameter 0.1-10 μ m (D that mixes equably thus ₅₀Be worth 2 μ m) stuff and other stuff.Except using this stuff and other stuff, similarly obtained negative pole with embodiment 2-1.

[embodiment 2-41 to 2-48]

Except obtain stuff and other stuff with the tin-copper stuff and other stuff shown in the mixed table 2-3 of table shown in the 2-3 and silver particles or copper particle, similarly obtained negative pole with embodiment 2-40.

[embodiment 2-49]

At the tin particle of suspension particle diameter 0.1-10 μ m and contain copper sulphate and during the plating of Rochelle salt bathes, this tin particle of chemical plating makes the surface-coated copper of this tin particle, the tin particle of the copper that obtains being covered.Tin particle concentration during plating is bathed is 500g/L, and the concentration of copper sulphate is 7.5g/L, and the concentration of Rochelle salt is 85g/L.The pH that plating is bathed is 12.5, and bathing temperature is 25 ℃.Use formaldehyde as reducing agent, its concentration is 22cc/L.In addition, similarly obtained negative pole with embodiment 2-1.

[embodiment 2-50 to 2-53]

Except the tin particle (embodiment 2-52 and 2-53) of the tin particle (embodiment 2-50 and 2-51) of the lining copper that uses the composition shown in the table 2-3 that obtains by chemical plating and lining nickel, similarly obtained negative pole with embodiment 2-41.

[comparative example 2-1]

Except the tin particle that replaces powdered graphite use particle diameter 5 μ m, similarly obtain negative pole with comparative example 1-1.

[performance evaluation]

The negative pole that use obtains in embodiment and comparative example has been made nonaqueous electrolytic solution secondary battery according to the method described above.Efficiency for charge-discharge and 50 circulation time capacity sustainment rates of weight capacity density, 10 circulation times when having measured irreversible capacity, charging with above-mentioned method.Following table 2-1 expresses these results to showing 2-3.

Table 2-1

		Coating		Negative electrode active material			Irreversible capacity (%)	Capacity density (mAh/g)	10 circulation time efficiency for charge-discharges (%)	50 circulation time capacity sustainment rates (%)
		Coating		Negative electrode active material							Thickness (μ m)	The coating material	Particle diameter D ₅₀ (μm)	Content in the coating (wt%)	Material ^*1(activated species)
		Embodiment	2-1	20	Cu	2					Thickness (μ m)	The coating material	Particle diameter D ₅₀ (μm)	Content in the coating (wt%)	Material ^*1(activated species)	70	Sn is only arranged	9	950	99.6	99
2-2	20		2-1	20	Cu	2	Ni	2	70	Sn is only arranged	14	910	99.3	96		70	Sn is only arranged	9	950	99.6	99
2-2	20		2-3	20	Co	2	Ni	2	70	Sn is only arranged	14	910	99.3	96	70	Sn is only arranged	13	900	99.1	96
2-4	20		2-3	20	Co	2	Cu	2	70	Sn60/Cu40 (alloy)	6	450	99.9	98	70	Sn is only arranged	13	900	99.1	96
2-4	20		2-5	20	Cu	2	Cu	2	70	Sn60/Cu40 (alloy)	6	450	99.9	98	70	Sn75/Cu25 (alloy)	6	650	99.9	94
2-6	20		2-5	20	Cu	2	Cu	2	70	Sn90/Cu10 (alloy)	6	850	99.9	99	70	Sn75/Cu25 (alloy)	6	650	99.9	94
2-6	20		2-7	20	Cu	2	Cu	2	70	Sn90/Cu10 (alloy)	6	850	99.9	99	70	Sn80/Ni20 (alloy)	6	500	99.9	92
2-8	20		2-7	20	Cu	2	Cu	2	70	Sn95/Ni5 (alloy)	6	850	99.9	99	70	Sn80/Ni20 (alloy)	6	500	99.9	92

^*1 ... numerical value means weight %.

Table 2-1 (continuing)

		Coating		Negative electrode active material			Irreversible capacity (%)	Capacity density (mAh/g)	10 circulation time efficiency for charge-discharges (%)	50 circulation time capacity sustainment rates (%)
		Coating		Negative electrode active material							Thickness (μ m)	The coating material	Particle diameter D ₅₀ (μm)	Content in the coating (wt%)	Material ^*1(activated species)
		Embodiment	2-9	20	Cu	2					Thickness (μ m)	The coating material	Particle diameter D ₅₀ (μm)	Content in the coating (wt%)	Material ^*1(activated species)	70	Sn80/Cu10/Ni10 (alloy)	6	750	99.9	97
2-10	20		2-9	20	Cu	2	Cu	2	70	Sn85/Cu10/Ni5 (alloy)	6	800	99.9	97		70	Sn80/Cu10/Ni10 (alloy)	6	750	99.9	97
2-10	20		2-11	20	Cu	2	Cu	2	70	Sn85/Cu10/Ni5 (alloy)	6	800	99.9	97	70	Sn80/Cu19.5/Al0.5 (alloy)	8	870	99.9	92
2-12	20		2-11	20	Cu	2	Cu	2	70	Sn80/Cu19.5/Ni0.5 (alloy)	9	810	99.9	96	70	Sn80/Cu19.5/Al0.5 (alloy)	8	870	99.9	92
2-12	20		2-13	20	Cu	2	Cu	2	70	Sn80/Cu19.5/Ni0.5 (alloy)	9	810	99.9	96	70	Sn80/Cu19.5/Co0.5 (alloy)	9	800	99.9	98
2-14	20		2-13	20	Cu	2	Cu	2	70	Sn80/Cu19.5/Ti0.5 (alloy)	8	820	99.9	94	70	Sn80/Cu19.5/Co0.5 (alloy)	9	800	99.9	98
2-14	20		2-15	20	Cu	2	Cu	2	70	Sn80/Cu19.5/Ti0.5 (alloy)	8	820	99.9	94	70	Sn80/Cu19.5/La0.5 (alloy)	9	860	99.9	97
2-16	20		2-15	20	Cu	2	Cu	2	70	Sn80/Cu19.5/Ce0.5 (alloy)	9	860	99.9	98	70	Sn80/Cu19.5/La0.5 (alloy)	9	860	99.9	97

^*1 ... numerical value means weight %.

Table 2-2

		Coating		Negative electrode active material			Irreversible capacity (%)	Capacity density (mAh/g)	10 circulation time efficiency for charge-discharges (%)	50 circulation time capacity sustainment rates (%)
		Coating		Negative electrode active material							Thickness (μ m)	The coating material	Particle diameter D ₅₀ (μm)	Content in the coating (wt%)	Material ^*1(activated species)
		Embodiment	2-17	20	Cu	2					Thickness (μ m)	The coating material	Particle diameter D ₅₀ (μm)	Content in the coating (wt%)	Material ^*1(activated species)	70	Sn (90)+Cu (10) (stuff and other stuff)	7	880	99.9	97
2-18	20		2-17	20	Cu	2	Cu	0.5	70	Sn (90)+Cu (10) (stuff and other stuff)	8	880	99.9	97		70	Sn (90)+Cu (10) (stuff and other stuff)	7	880	99.9	97
2-18	20		2-19	20	Cu	10	Cu	0.5	70	Sn (90)+Cu (10) (stuff and other stuff)	8	880	99.9	97	70	Sn (90)+Cu (10) (stuff and other stuff)	7	880	99.9	92
2-20	20		2-19	20	Cu	10	Cu	0.2	70	Sn (90)+Cu (10) (stuff and other stuff)	7	880	99.10	93	70	Sn (90)+Cu (10) (stuff and other stuff)	7	880	99.9	92
2-20	20		2-21	20	Cu	1	Cu	0.2	70	Sn (90)+Cu (10) (stuff and other stuff)	7	880	99.10	93	70	Sn (90)+Cu (10) (stuff and other stuff)	7	880	99.11	97
2-22	20		2-21	20	Cu	1	Cu	5	70	Sn (90)+Cu (10) (stuff and other stuff)	7	880	99.12	95	70	Sn (90)+Cu (10) (stuff and other stuff)	7	880	99.11	97
2-22	20		2-23	20	Cu	20	Cu	5	70	Sn (90)+Cu (10) (stuff and other stuff)	7	880	99.12	95	70	Sn (90)+Cu (10) (stuff and other stuff)	7	880	99.13	98
2-24	20		2-23	20	Cu	20	Cu	2	30	Sn (90)+Cu (10) (stuff and other stuff)	7	880	99.9	94	70	Sn (90)+Cu (10) (stuff and other stuff)	7	880	99.13	98
2-24	20		2-25	20	Cu	2	Cu	2	30	Sn (90)+Cu (10) (stuff and other stuff)	7	880	99.9	94	50	Sn (90)+Cu (10) (stuff and other stuff)	7	880	99.9	99
2-26	5		2-25	20	Cu	2	Cu	1	70	Sn (90)+Cu (10) (stuff and other stuff)	8	880	99.9	99	50	Sn (90)+Cu (10) (stuff and other stuff)	7	880	99.9	99
2-26	5		2-27	10	Cu	2	Cu	1	70	Sn (90)+Cu (10) (stuff and other stuff)	8	880	99.9	99	70	Sn (90)+Cu (10) (stuff and other stuff)	7	880	99.9	96

^*1 ... numerical value means weight %.

Table 2-2 (continuing)

		Coating		Negative electrode active material			Irreversible capacity (%)	Capacity density (mAh/g)	10 circulation time efficiency for charge-discharges (%)	50 circulation time capacity sustainment rates (%)
		Coating		Negative electrode active material							Thickness (μ m)	The coating material	Particle diameter D ₅₀ (μm)	Content in the coating (wt%)	Material ^*1(activated species)
		Embodiment	2-28	15	Cu	2					Thickness (μ m)	The coating material	Particle diameter D ₅₀ (μm)	Content in the coating (wt%)	Material ^*1(activated species)	70	Sn (90)+Cu (10) (stuff and other stuff)	7	880	99.9	97
2-29	20		2-28	15	Cu	2	Cu	2	70	Sn (60)+Cu (40) (stuff and other stuff)	8	590	99.9	98		70	Sn (90)+Cu (10) (stuff and other stuff)	7	880	99.9	97
2-29	20		2-30	20	Cu	2	Cu	2	70	Sn (60)+Cu (40) (stuff and other stuff)	8	590	99.9	98	70	Sn (75)+Cu (25) (stuff and other stuff)	8	740	99.9	98
2-31	20		2-30	20	Cu	2	Cu	2	70	Sn (95)+Cu (5) (stuff and other stuff)	8	890	99.9	92	70	Sn (75)+Cu (25) (stuff and other stuff)	8	740	99.9	98
2-31	20		2-32	20	Cu	2	Cu	2	70	Sn (95)+Cu (5) (stuff and other stuff)	8	890	99.9	92	70	Sn (99)+Ag (1) (stuff and other stuff)	5	900	99.9	93
2-33	20		2-32	20	Cu	2	Cu	2	70	Sn (95)+Ag (5) (stuff and other stuff)	5	890	99.9	96	70	Sn (99)+Ag (1) (stuff and other stuff)	5	900	99.9	93
2-33	20		2-34	20	Cu	2	Cu	2	70	Sn (95)+Ag (5) (stuff and other stuff)	5	890	99.9	96	70	Sn (90)+Ag (10) (stuff and other stuff)	5	870	99.9	94
2-35	20		2-34	20	Cu	2	Cu	2	70	Sn (80)+Ag (20) (stuff and other stuff)	5	850	99.9	92	70	Sn (90)+Ag (10) (stuff and other stuff)	5	870	99.9	94
2-35	20		2-36	20	Cu	2	Cu	2	70	Sn (80)+Ag (20) (stuff and other stuff)	5	850	99.9	92	60	Sn (90)+Si (10) (stuff and other stuff)	7	980	99.9	92
2-37	20		2-36	20	Cu	2	Cu	2	60	Sn (50)+Si (50) (stuff and other stuff)	7	2500	99.9	93	60	Sn (90)+Si (10) (stuff and other stuff)	7	980	99.9	92
2-37	20		2-38	20	Cu	2	Cu	2	60	Sn (50)+Si (50) (stuff and other stuff)	7	2500	99.9	93	60	Sn (50)+Si (40)+Cu (10) (stuff and other stuff)	7	2200	99.9	96
2-39	20		2-38	20	Cu	2	Cu	2	60	Sn (50)+Si (40)+Cu (10) (stuff and other stuff)	7	2200	99.9	97	60	Sn (50)+Si (40)+Cu (10) (stuff and other stuff)	7	2200	99.9	96

^*1 ... numerical value means weight %.

Table 2-3

		Coating		Negative electrode active material			Irreversible capacity (%)	Capacity density (mAh/g)	10 circulation time efficiency for charge-discharges (%)	50 circulation time capacity sustainment rates (%)
		Coating		Negative electrode active material							Thickness (μ m)	The coating material	Particle diameter D ₅₀ (μm)	Content in the coating (wt%)	Material ^*1(activated species)
		Embodiment	2-40	20	Cu	2					Thickness (μ m)	The coating material	Particle diameter D ₅₀ (μm)	Content in the coating (wt%)	Material ^*1(activated species)	70	Sn75/Cu25 (99)+Ag (1) (stuff and other stuff)	5	690	99.9	94
2-41	20		2-40	20	Cu	2	Cu	2	70	Sn75/Cu25 (95)+Ag (5) (stuff and other stuff)	5	680	99.9	98		70	Sn75/Cu25 (99)+Ag (1) (stuff and other stuff)	5	690	99.9	94
2-41	20		2-42	20	Cu	2	Cu	2	70	Sn75/Cu25 (95)+Ag (5) (stuff and other stuff)	5	680	99.9	98	70	Sn75/Cu25 (90)+Ag (10) (stuff and other stuff)	5	670	99.9	99
2-43	20		2-42	20	Cu	2	Cu	2	70	Sn75/Cu25 (80)+Ag (20) (stuff and other stuff)	5	640	99.9	99	70	Sn75/Cu25 (90)+Ag (10) (stuff and other stuff)	5	670	99.9	99
2-43	20		2-44	20	Cu	2	Cu	2	70	Sn75/Cu25 (80)+Ag (20) (stuff and other stuff)	5	640	99.9	99	70	Sn75/Cu25 (99)+Cu (1) (stuff and other stuff)	5	680	99.9	93
2-45	20		2-44	20	Cu	2	Cu	2	70	Sn75/Cu25 (95)+Cu (5) (stuff and other stuff)	5	670	99.9	96	70	Sn75/Cu25 (99)+Cu (1) (stuff and other stuff)	5	680	99.9	93
2-45	20		2-46	20	Cu	2	Cu	2	70	Sn75/Cu25 (95)+Cu (5) (stuff and other stuff)	5	670	99.9	96	70	Sn75/Cu25 (90)+Cu (10) (stuff and other stuff)	5	620	99.9	97

^*1 ... numerical value means weight %.

Table 2-3 (continuing)

		Coating		Negative electrode active material			Irreversible capacity (%)	Capacity density (mAh/g)	10 circulation time efficiency for charge-discharges (%)	50 circulation time capacity sustainment rates (%)
		Coating		Negative electrode active material							Thickness (μ m)	The coating material	Particle diameter D ₅₀ (μm)	Content in the coating (wt%)	Material ^*1(activated species)
		Embodiment	2-47	20	Cu	2					Thickness (μ m)	The coating material	Particle diameter D ₅₀ (μm)	Content in the coating (wt%)	Material ^*1(activated species)	70	Sn75/Cu25 (80)+Cu (20) (stuff and other stuff)	5	600	99.9	93
2-48	20		2-47	20	Cu	2	Cu	2	70	Sn75/Cu25 (60)+Cu40 (stuff and other stuff)	5	450	99.9	94		70	Sn75/Cu25 (80)+Cu (20) (stuff and other stuff)	5	600	99.9	93
2-48	20		2-49	20	Cu	2	Cu	2	70	Sn75/Cu25 (60)+Cu40 (stuff and other stuff)	5	450	99.9	94	70	Sn80/Cu20 (chemical plating)	5	790	99.9	99
2-50	20		2-49	20	Cu	2	Cu	2	70	Sn95/Cu5 (chemical plating)	5	910	99.9	98	70	Sn80/Cu20 (chemical plating)	5	790	99.9	99
2-50	20		2-51	20	Cu	2	Cu	2	70	Sn95/Cu5 (chemical plating)	5	910	99.9	98	70	Sn99/Cu1 (chemical plating)	6	930	99.9	96
2-52	20		2-51	20	Cu	2	Cu	2	70	Sn99/Ni1 (chemical plating)	11	900	99.9	96	70	Sn99/Cu1 (chemical plating)	6	930	99.9	96
2-52	20		2-53	20	Cu	2	Cu	2	70	Sn99/Ni1 (chemical plating)	11	900	99.9	96	70	Sn99.5/Ni0.5 (chemical plating)	7	930	99.9	95
Comparative example	2-1		2-53	20	Cu	2	No coating		5	80	Sn is only arranged	20	950	95.0	70	Sn99.5/Ni0.5 (chemical plating)	7	930	99.9	95	7

^*1 ... numerical value means weight %.

2-1 clearly distinguishes to showing the result shown in the 2-3 by table, used the secondary cell of the negative pole that in each embodiment, obtains, demonstrated and used irreversible capacity, efficiency for charge-discharge and the capacity density of secondary cell same degree of the negative pole of comparative example, and the capacity sustainment rate is high more a lot of than the secondary cell of comparative example.

[embodiment 3-1]

(1) preparation of plating bath

Having prepared the plating with following composition bathes.

Silicon particle (particle diameter D ₅₀Be worth 5 μ m) 600g/L

Copper sulphate 50g/L

Sulfuric acid 70g/L

Cresol sulfonic acid 70g/L

Gelatin 2g/L

Betanaphthol 1.5g/L

(2) disperse plating

Under the state that makes the silicon particle suspension in plating is bathed, the Copper Foil of thickness 30 μ m is immersed in 20 ℃ plating carries out electrolysis in bathing.Current density is 10A/dm ²Formed the surface-coated layer that the copper by lining silicon particle homodisperse active material layer constitutes in view of the above.The result of electron microscope observation, the thickness that comprises the active material structure of active material layer and surface-coated layer is 35 μ m.Chemico-analytic result, the amount of the silicon particle in the active material structure is 30%.

[embodiment 3-2]

(1) preparation of slurry

The slurry that has prepared following composition.

Silicon particle (particle diameter D ₅₀Be worth 5 μ m) 16%

Acetylene carbon black (particle diameter 0.1 μ m) 2%

Adhesive (Kynoar) 2%

Retarder thinner (N-methyl pyrrolidone) 80%

(2) formation of active material layer

Prepared slurry coating is made it dry on the Copper Foil of thickness 30 μ m.The thickness of dried active material layer is 60 μ m.

(3) formation of surface-coated layer

Copper 50g/L

Sulfuric acid 60g/L

Bathe 40 ℃ of temperature

After forming surface-coated layer, mention Copper Foil, thereby reinstate roll-in system active substance for processing layer densificationization with surface-coated layer one in succession from the plating bath.The thickness of the active material structure that obtains like this, the result of electron microscope observation is 30 μ m.In addition, chemico-analytic result, the amount of the silicon particle in the active material structure is 35%, the amount of acetylene carbon black is 5%.

[embodiment 3-3 and 3-4]

Except form coating by nickel (embodiment 3-3), cobalt (embodiment 3-4), similarly obtained negative pole with embodiment 3-2.

[embodiment 3-5]

1400 ℃ the motlten metal that will contain silicon 50% bronze medal 50% pours in the mold made of copper, obtains by the ingot casting of the silicon-copper alloy of chilling.This ingot casting is crushed and screened, use the particle of particle diameter 0.1-10 μ m then.Except using this alloy particle, similarly obtained negative pole with embodiment 3-2.

[embodiment 3-6 to 3-8]

Except silicon-copper alloy particles of using the composition shown in the table 3-1, similarly obtained negative pole with embodiment 3-5.

[embodiment 3-9 to 3-11]

Except the silicon-nickel alloy particle that uses the composition shown in the table 3-1, similarly obtained negative pole with embodiment 3-5.

[embodiment 3-12 and 3-13]

Except the silicon-copper-nickel alloy particle that uses the composition shown in the table 3-1, similarly obtained negative pole with embodiment 3-5.

[embodiment 3-14]

Mix silicon particle (particle diameter 100 μ m) 80% and copper particle (particle diameter 30 μ m) 20%, adopt vertical ball mill to carry out the mixing and the pulverizing of these particles simultaneously.Obtain the particle diameter 2-10 μ m (D that silicon and copper mix equably thus ₅₀Be worth 5 μ m) stuff and other stuff.Except using this stuff and other stuff, similarly obtained negative pole with embodiment 3-2.

[embodiment 3-15 to 3-26]

Except the silicon-copper stuff and other stuff of composition shown in the use table 3-2 and particle diameter and make active material structure thickness, similarly obtained negative pole with embodiment 3-14 for the value shown in this table.

[embodiment 3-27]

At the silicon particle of suspension particle diameter 0.2-8 μ m and contain copper sulphate and during the plating of Rochelle salt bathes, this silicon particle of chemical plating makes the surface-coated copper of this silicon particle, the silicon particle of the copper that obtains being covered.Silicon particle concentration during plating is bathed is 500g/L, and the concentration of copper sulphate is 7.5g/L, and the concentration of Rochelle salt is 85g/L.The pH that plating is bathed is 12.5, and bathing temperature is 25 ℃.Use formaldehyde as reducing agent, its concentration is 22cc/L.In addition, similarly obtained negative pole with embodiment 3-2.

[embodiment 3-28 to 3-31]

Except the silicon particle (embodiment 3-30 and 3-31) of the silicon particle (embodiment 3-28 and 3-29) of the lining copper that uses the composition shown in the table 3-2 that obtains by chemical plating and lining nickel, similarly obtained negative pole with embodiment 3-18.

[embodiment 3-32 to 3-37]

Except the silicon that use to adopt the composition shown in the table 3-3 that quench obtains is the ternary alloy three-partalloy particle, similarly obtained negative pole with embodiment 3-5.

[embodiment 3-38]

Mix silicon particle (particle diameter 100 μ m) 20% and graphite particle (D ₅₀Be worth 20 μ m) 80%, adopt machinery to grind mixing and the pulverizing that method is carried out these particles simultaneously.Obtain the particle diameter 0.5 μ m (D that silicon and graphite mix equably thus ₅₀Value) stuff and other stuff.Except using this stuff and other stuff and forming surface-coated layer, similarly obtained negative pole with embodiment 3-2 by nickel.

[embodiment 3-39 to 3-42]

Except making the consisting of the value of table shown in the 3-3 of stuff and other stuff, similarly obtained negative pole with embodiment 3-38.

[embodiment 3-43]

Except using the alloy particle formed by silicon 80%, copper 19%, lithium 1% and constituting surface-coated layer, similarly obtained negative pole with embodiment 3-5 by Ni.

[performance evaluation]

Use the negative pole that obtains in an embodiment, made nonaqueous electrolytic solution secondary battery according to the method described above.Efficiency for charge-discharge and 50 circulation time capacity sustainment rates of weight capacity density, 10 circulation times when having measured irreversible capacity, charging with above-mentioned method.Following table 3-1 expresses these results to showing 3-3.

Table 3-1

		Active material structure							Irreversible capacity (%)	Capacity density (mAh/g)	10 circulation time efficiency for charge-discharges (%)	50 circulation time capacity sustainment rates (%)
		Active material structure											Thickness (μ m)	Surface-coated layer		The active material layer of silicon based material
		Thickness (μ m)	Material	Thickness (μ m)	Particle diameter D ₅₀ (μm)	Content in the active material structure (wt%)	Material							Surface-coated layer		The active material layer of silicon based material
		Thickness (μ m)	Material	Thickness (μ m)	Particle diameter D ₅₀ (μm)	Content in the active material structure (wt%)	Material	Embodiment						3-1	30	5	Cu	25	5	30	Si is only arranged	12	4010	99.6	95
3-2	30	5	Cu	25	5	35	Si is only arranged		9	4010	99.7	95		3-1	30	5	Cu	25	5	30	Si is only arranged	12	4010	99.6	95
3-2	30	5	Cu	25	5	35	Si is only arranged		9	4010	99.7	95	3-3	30	5	Ni	25	5	35	Si is only arranged	14	3700	99.5	96
3-4	30	5	Co	25	5	35	Si is only arranged		13	3600	99.5	96	3-3	30	5	Ni	25	5	35	Si is only arranged	14	3700	99.5	96
3-4	30	5	Co	25	5	35	Si is only arranged		13	3600	99.5	96	3-5	30	5	Cu	25	5	45	Si50/Cu50	5	2000	99.7	99
3-6	30	5	Cu	25	5	40	Si60/Cu40		6	2400	99.7	99	3-5	30	5	Cu	25	5	45	Si50/Cu50	5	2000	99.7	99
3-6	30	5	Cu	25	5	40	Si60/Cu40		6	2400	99.7	99	3-7	30	5	Cu	25	5	40	Si70/Cu30	6	2800	99.7	99
3-8	30	5	Cu	25	5	38	Si80/Cu20		6	3200	99.7	99	3-7	30	5	Cu	25	5	40	Si70/Cu30	6	2800	99.7	99
3-8	30	5	Cu	25	5	38	Si80/Cu20		6	3200	99.7	99	3-9	30	5	Cu	25	5	45	Si50/Ni50	6	500	99.7	99
3-10	30	5	Cu	25	5	40	Si65/Ni35		6	800	99.7	99	3-9	30	5	Cu	25	5	45	Si50/Ni50	6	500	99.7	99
3-10	30	5	Cu	25	5	40	Si65/Ni35		6	800	99.7	99	3-11	30	5	Cu	25	5	35	Si80/Ni20	6	1300	99.7	99
3-12	30	5	Cu	25	5	40	Si60/Cu20/ Ni20		6	2000	99.7	99	3-11	30	5	Cu	25	5	35	Si80/Ni20	6	1300	99.7	99
3-12	30	5	Cu	25	5	40	Si60/Cu20/ Ni20		6	2000	99.7	99	3-13	30	5	Cu	25	5	40	Si70/Cu15/ Ni15	6	2300	99.7	99

Table 3-2

		Active material structure							Irreversible capacity (%)	Capacity density (mAh/g)	10 circulation time efficiency for charge-discharges (%)	50 circulation time capacity sustainment rates (%)
		Active material structure											Thickness (μ m)	Surface-coated layer		The active material layer of silicon based material
		Thickness (μ m)	Material	Thickness (μ m)	Particle diameter D ₅₀ (μm)	Content in the active material structure (wt%)	Material							Surface-coated layer		The active material layer of silicon based material
		Thickness (μ m)	Material	Thickness (μ m)	Particle diameter D ₅₀ (μm)	Content in the active material structure (wt%)	Material	Embodiment						3-14	30	5	Cu	25	5	38	Si80/Cu20	7	3200	99.7	99
3-15	30	5	Cu	25	0.8	38	Si80/Cu20		8	3200	99.9	100		3-14	30	5	Cu	25	5	38	Si80/Cu20	7	3200	99.7	99
3-15	30	5	Cu	25	0.8	38	Si80/Cu20		8	3200	99.9	100	3-16	30	5	Cu	25	10	38	Si80/Cu20	7	3200	99.7	96
3-17	30	5	Cu	25	20	38	Si80/Cu20		7	3200	99.6	95	3-16	30	5	Cu	25	10	38	Si80/Cu20	7	3200	99.7	96
3-17	30	5	Cu	25	20	38	Si80/Cu20		7	3200	99.6	95	3-18	30	5	Cu	25	5	10	Si80/Cu20	7	3200	99.8	99
3-19	30	5	Cu	25	5	20	Si80/Cu20		7	3200	99.7	99	3-18	30	5	Cu	25	5	10	Si80/Cu20	7	3200	99.8	99
3-19	30	5	Cu	25	5	20	Si80/Cu20		7	3200	99.7	99	3-20	5	1	Cu	4	1	38	Si80/Cu20	8	3200	99.8	99
3-21	10	2	Cu	8	5	38	Si80/Cu20		7	3200	99.7	99	3-20	5	1	Cu	4	1	38	Si80/Cu20	8	3200	99.8	99
3-21	10	2	Cu	8	5	38	Si80/Cu20		7	3200	99.7	99	3-22	15	3	Cu	12	5	38	Si80/Cu20	7	3200	99.7	99
3-23	20	4	Cu	16	5	38	Si80/Cu20		7	3200	99.7	99	3-22	15	3	Cu	12	5	38	Si80/Cu20	7	3200	99.7	99
3-23	20	4	Cu	16	5	38	Si80/Cu20		7	3200	99.7	99	3-24	30	5	Cu	25	5	37	Si90/Cu10	8	3600	99.7	98
3-25	30	5	Cu	25	5	36	Si95/Cu5		8	3600	99.7	98	3-24	30	5	Cu	25	5	37	Si90/Cu10	8	3600	99.7	98
3-25	30	5	Cu	25	5	36	Si95/Cu5		8	3600	99.7	98	3-26	30	5	Cu	25	5	36	Si95/Ni5	9	3500	99.7	98
3-27	30	5	Cu	25	5	35	Si80/Cu20		5	3200	99.7	99	3-26	30	5	Cu	25	5	36	Si95/Ni5	9	3500	99.7	98
3-27	30	5	Cu	25	5	35	Si80/Cu20		5	3200	99.7	99	3-28	30	5	Cu	25	5	35	Si80/Cu20	5	3800	99.7	99
3-29	30	5	Cu	25	5	35	Si99/Cu1		6	3900	99.7	99	3-28	30	5	Cu	25	5	35	Si80/Cu20	5	3800	99.7	99
3-29	30	5	Cu	25	5	35	Si99/Cu1		6	3900	99.7	99	3-30	30	5	Cu	25	5	35	Si99/Ni1	11	3900	99.7	99
3-31	30	5	Cu	25	5	35	Si99.5/Ni0.5		7	4000	99.7	99	3-30	30	5	Cu	25	5	35	Si99/Ni1	11	3900	99.7	99

Table 3-3

		Active material structure							Irreversible capacity (%)	Capacity density (mAh/g)	10 circulation time efficiency for charge-discharges (%)	50 circulation time capacity sustainment rates (%)
		Active material structure											Thickness (μ m)	Surface-coated layer		The active material layer of silicon based material
		Thickness (μ m)	Material	Thickness (μ m)	Particle diameter D ₅₀ (μm)	Content in the active material structure (wt%)	Material							Surface-coated layer		The active material layer of silicon based material
		Thickness (μ m)	Material	Thickness (μ m)	Particle diameter D ₅₀ (μm)	Content in the active material structure (wt%)	Material	Embodiment						3-32	30	5	Cu	25	5	38	Si80/Cu19.5/A10.5	8	3100	99.7	99
3-33	30	5	Cu	25	5	38	Si80/Cu19.5/Ni0.5		9	3100	99.7	99		3-32	30	5	Cu	25	5	38	Si80/Cu19.5/A10.5	8	3100	99.7	99
3-33	30	5	Cu	25	5	38	Si80/Cu19.5/Ni0.5		9	3100	99.7	99	3-34	30	5	Cu	25	5	38	Si80/Cu19.5/Co0.5	9	3000	99.7	99
3-35	30	5	Cu	25	5	38	Si80/Cu19.5/Ti0.5		8	3100	99.7	99	3-34	30	5	Cu	25	5	38	Si80/Cu19.5/Co0.5	9	3000	99.7	99
3-35	30	5	Cu	25	5	38	Si80/Cu19.5/Ti0.5		8	3100	99.7	99	3-36	30	5	Cu	25	5	38	Si80/Cu19.5/La0.5	9	3060	99.7	99
3-37	30	5	Cu	25	5	38	Si80/Cu19.5/Ce0.5		9	3070	99.7	99	3-36	30	5	Cu	25	5	38	Si80/Cu19.5/La0.5	9	3060	99.7	99
3-37	30	5	Cu	25	5	38	Si80/Cu19.5/Ce0.5		9	3070	99.7	99	3-38	30	5	Ni	25	0.5	35	Si20/C80	6	1040	99.8	100
3-39	30	5	Ni	25	0.5	35	Si40/C60		6	1740	99.8	97	3-38	30	5	Ni	25	0.5	35	Si20/C80	6	1040	99.8	100
3-39	30	5	Ni	25	0.5	35	Si40/C60		6	1740	99.8	97	3-40	30	5	Ni	25	0.5	35	Si40/C40/Cu20	6	1600	99.8	97
3-41	30	5	Ni	25	0.5	35	Si60/C40		7	2510	99.7	94	3-40	30	5	Ni	25	0.5	35	Si40/C40/Cu20	6	1600	99.8	97
3-41	30	5	Ni	25	0.5	35	Si60/C40		7	2510	99.7	94	3-42	30	5	Ni	25	0.5	35	Si80/C20	8	3230	99.7	92
3-43	30	5	Ni	25	5	38	Si80/Cu19/Li1		0	3200	100	100	3-42	30	5	Ni	25	0.5	35	Si80/C20	8	3230	99.7	92

3-1 distinguishes clearly that to showing the result shown in the 3-3 used the secondary cell of the negative pole that obtains in each embodiment, irreversible capacity, efficiency for charge-discharge, capacity sustainment rate and capacity density are all very high by table.

According to negative electrode for nonaqueous secondary battery of the present invention, can access the secondary cell that energy density is higher than negative pole in the past.In addition, according to negative electrode for nonaqueous secondary battery of the present invention, prevented that active material from peeling off from collector body, even repeated charge has also been guaranteed the current collection of active material.In addition, even used the secondary cell repeated charge deterioration rate of this negative pole also low, the life-span prolongs significantly, and efficiency for charge-discharge also uprises.

Claims

1. negative electrode for nonaqueous secondary battery, it is characterized in that, on the single face of collector body or two sides, form the active material structure of the low conductive material of the formation ability that contains lithium compound, the active material particle that contains the high material of the formation ability that contains lithium compound of 5-80 weight % in this active material structure, described active material structure have the active material layer that contains described active material particle and are positioned at surface-coated layer on this active material layer.

2. negative electrode for nonaqueous secondary battery according to claim 1, wherein, the described material that the formation ability of lithium compound is high is tin or silicon.

3. negative electrode for nonaqueous secondary battery according to claim 1 wherein, contains the conductive carbon material of 0.1-20 weight % in described active material layer.

4. negative electrode for nonaqueous secondary battery according to claim 1, wherein, the constituent material of described surface-coated layer enters into described active material layer or this material reaches described collector body.

5. negative electrode for nonaqueous secondary battery according to claim 1, wherein, the constituent material of described surface-coated layer soaks into to described active material layer integral body.

6. negative electrode for nonaqueous secondary battery according to claim 1 wherein, has formed a large amount of fine pores that thickness direction extends and nonaqueous electrolytic solution can soak into to this surface-coated layer in described surface-coated layer.

7. negative electrode for nonaqueous secondary battery according to claim 2, wherein, described active material particle is the particle of silicon or tin simple substance.

8. negative electrode for nonaqueous secondary battery according to claim 2, wherein, described active material particle is the stuff and other stuff of silicon or tin and carbon at least, this stuff and other stuff contains the silicon of 10-90 weight % or the carbon of tin and 90-10 weight %.

9. negative electrode for nonaqueous secondary battery according to claim 2, wherein, described active material particle is the stuff and other stuff of silicon or tin and metal and/or B, and this stuff and other stuff contains the silicon of 30-99.9 weight % and a kind or the multiple element selecting of 0.1-70 weight % from Cu, Ag, Li, Ni, Co, Fe, Cr, Zn, B, Al, Ge, Sn, In, V, Ti, Y, Zr, Nb, Ta, W, La, Ce, Pr, Pd and Nd; Perhaps this stuff and other stuff contains the tin of 30-99.9 weight % and a kind or the multiple element selecting of 0.1-70 weight % from Cu, Ag, Li, Ni, Co, Fe, Cr, Zn, B, Al, Ge, Si, In, V, Ti, Y, Zr, Nb, Ta, W, La, Ce, Pr, Pd and Nd.

10. negative electrode for nonaqueous secondary battery according to claim 2, wherein, described active material particle is the particle of silicon compound or tin compound, and the particle of this silicon compound or tin compound contains the silicon of 30-99.9 weight % and a kind or the multiple element selecting of 0.1-70 weight % from Cu, Ag, Li, Ni, Co, Fe, Cr, Zn, B, Al, Ge, Sn, In, V, Ti, Y, Zr, Nb, Ta, W, La, Ce, Pr, Pd and Nd; Perhaps the particle of this silicon compound or tin compound contains the tin of 30-99.9 weight % and a kind or the multiple element selecting of 0.1-70 weight % from Cu, Ag, Li, Ni, Co, Fe, Cr, Zn, B, Al, Ge, Si, In, V, Ti, Y, Zr, Nb, Ta, W, La, Ce, Pr, Pd and Nd.

11. negative electrode for nonaqueous secondary battery according to claim 2, wherein, described active material particle is the stuff and other stuff of particle and the metallic and/or the beta particle of silicon compound or tin compound, and described stuff and other stuff contains the particle of the particle of silicon compound of 30-99.9 weight % and 0.1-70 weight % select a kind or multiple element from Cu, Ag, Li, Ni, Co, Fe, Cr, Zn, B, Al, Ge, Sn, In, V, Ti, Y, Zr, Nb, Ta, W, La, Ce, Pr, Pd and Nd; Perhaps described stuff and other stuff contains the particle of tin compound of 30-99.9 weight % and a kind or the particle of multiple element selecting of 0.1-70 weight % from Cu, Ag, Li, Ni, Co, Fe, Cr, Zn, B, Al, Ge, Si, In, V, Ti, Y, Zr, Nb, Ta, W, La, Ce, Pr, Pd and Nd

The particle of described compound contains the silicon of 30-99.9 weight % and a kind or the multiple element selecting of 0.1-70 weight % from Cu, Ag, Li, Ni, Co, Fe, Cr, Zn, B, Al, Ge, Sn, In, V, Ti, Y, Zr, Nb, Ta, W, La, Ce, Pr, Pd and Nd; Perhaps the particle of described compound contains the tin of 30-99.9 weight % and a kind or the multiple element selecting of 0.1-70 weight % from Cu, Ag, Li, Ni, Co, Fe, Cr, Zn, B, Al, Ge, Si, In, V, Ti, Y, Zr, Nb, Ta, W, La, Ce, Pr, Pd and Nd.

12. negative electrode for nonaqueous secondary battery according to claim 2, wherein, described active material particle is at the particle surface coated metal of elementary silicon or tin simple substance and/or the particle that B forms, and this particle contains the silicon of 70-99.9 weight % and a kind or the multiple element selecting of 0.1-30 weight % from Cu, Ag, Ni, Co, Fe, Cr, Zn, B, Al, Ge, Sn, In, V, Ti, Y, Zr, Nb, Ta, W, La, Ce, Pr, Pd and Nd; Perhaps this particle contains the tin of 70-99.9 weight % and a kind or the multiple element selecting of 0.1-30 weight % from Cu, Ag, Li, Ni, Co, Fe, Cr, Zn, B, Al, Ge, Si, In, V, Ti, Y, Zr, Nb, Ta, W, La, Ce, Pr, Pd and Nd.

13. negative electrode for nonaqueous secondary battery according to claim 1, wherein, the maximum particle diameter of described active material particle is 50 μ m or following.

14. negative electrode for nonaqueous secondary battery according to claim 1, wherein, described active material particle contains silicon, average grain diameter D ₅₀Be 0.1-10 μ m, the oxygen concentration less than 2.5 weight % of described active material particle and surpass 1/2 of oxygen concentration at the most surperficial silicon concentration.

15. negative electrode for nonaqueous secondary battery according to claim 1, wherein, described surface-coated layer contains a kind or the multiple element of selecting from Cu, Ag, Ni, Co, Cr, Fe and In.

16. negative electrode for nonaqueous secondary battery according to claim 1, wherein, described surface-coated layer forms by plating.

17. negative electrode for nonaqueous secondary battery according to claim 1, wherein, described surface-coated layer adopts sputtering method, chemical vapor coating method or physical vapor vapour deposition method to form.

18. negative electrode for nonaqueous secondary battery according to claim 1, wherein, described surface-coated layer forms by the rolling of conductivity paper tinsel.

19. negative electrode for nonaqueous secondary battery according to claim 18, wherein, described conductivity paper tinsel is metal forming or Markite paper tinsel.

20. negative electrode for nonaqueous secondary battery according to claim 1, wherein, described active material layer forms by the slurry that the surface coated at described collector body contains described active material particle.

21. negative electrode for nonaqueous secondary battery according to claim 1, wherein, the thickness of described surface-coated layer is 0.3-50 μ m, and the thickness of described active material layer is 1-100 μ m.

22. negative electrode for nonaqueous secondary battery according to claim 1, wherein, the thickness of described surface-coated layer is 0.3-50 μ m, and the thickness of described active material structure is 2-100 μ m.

23. negative electrode for nonaqueous secondary battery according to claim 1, wherein, the thickness of described surface-coated layer is 0.3-50 μ m, and the thickness of electrode integral body is 2-200 μ m.

24. negative electrode for nonaqueous secondary battery according to claim 1, wherein, described collector body has the minute aperture of a large amount of diameter 0.01-200 μ m, and the density that exists of this minute aperture is 5-10000/cm ², thickness is 1-100 μ m.

25. negative electrode for nonaqueous secondary battery according to claim 1, wherein, described collector body is by having a large amount of 0.0001-4mm ²The punch metal of perforate or porous metals constitute or constitute by metal foam body.

26. negative electrode for nonaqueous secondary battery according to claim 1, wherein, described collector body is made of the electrolytic metal paper tinsel.

27. make the method for the described negative electrode for nonaqueous secondary battery of claim 3, it is characterized in that, the slurry coating that will contain described active material particle, described conductive carbon material, adhesive and retarder thinner is on described collector body surface, make dried coating film form described active material layer, then, on this active material layer, carry out the plating of the low described conductive material of the formation ability of lithium compound, form described surface-coated layer.

28. make the method for the described negative electrode for nonaqueous secondary battery of claim 3, it is characterized in that, the slurry coating that will contain described active material particle, described conductive carbon material, adhesive and retarder thinner is on described collector body surface, make dried coating film form described active material layer, then, on this active material layer, implement sputtering method, chemical vapor coating method or physical vapor vapour deposition method, the described surface-coated layer of the described conductive material that the formation ability of formation lithium compound is low.

29. make the method for the described negative electrode for nonaqueous secondary battery of claim 24, it is characterized in that, on foils, form the lining body that constitutes by material with the constituent material unlike material of described collector body with the thickness of 0.001-1 μ m, thereby make the constituent material electrolysis of described collector body go out to form this collector body by plating in the above, to contain described active material particle, conductive carbon material, the slurry coating of adhesive and retarder thinner is on described collector body surface, make dried coating film form described active material layer, on described active material layer, carry out the plating of the low described conductive material of the formation ability of lithium compound, form described surface-coated layer, described collector body is peeled off from described foils.

30. a nonaqueous electrolytic solution secondary battery, it possesses the described negative electrode for nonaqueous secondary battery of claim 1.