CN101252180B

CN101252180B - Active material particle for electrode, electrode, electrochemical device, and production method of electrode

Info

Publication number: CN101252180B
Application number: CN2008100817125A
Authority: CN
Inventors: 栗原雅人
Original assignee: TDK Corp
Current assignee: TDK Corp
Priority date: 2007-02-23
Filing date: 2008-02-25
Publication date: 2012-06-13
Anticipated expiration: 2028-02-25
Also published as: CN101252180A; JP5228501B2; JP2008235252A

Abstract

The present invention provides an active material particle for electrode including an active material body 4, and a conductive aid 6 with electron conductivity partially covering a surface of the active material body 4, a projection 8 comprised of the conductive aid 6 is formed on the surface of the active material body 4, and a height of the projection 8 from the surface of the active material body 4 is not less than 5% nor more than 30% of a particle size of the active material body 4.

Description

Active material particle for electrode, electrode, electrochemical appliance and electrode manufacturing method

Technical field

The present invention relates to the manufacturing approach of active material particle for electrode, electrode, electrochemical appliance and electrode.

Background technology

Marvelous achievement is arranged in the development of portable set in recent years, and as its bigger motive power, the lithium rechargeable battery that can enumerate to be made the power supply of these equipment by extensive employing is the development of the high energy battery of representative.This high energy battery mainly by negative electrode, anode and be disposed at negative electrode and anode between dielectric substrate (such as by the formed layer of aqueous electrolyte or solid electrolyte) constitute.

So; About being the high energy battery of representative with the lithium rechargeable battery and being the electrochemical appliance of the electrochemical capacitor etc. of representative with the double electric layer capacitor; For corresponding to the development from now on of the equipment that should be provided with electrochemical appliance of portable set etc. and further improve its characteristic, various research and development have been carried out.Particularly expectation realizes having the electrochemical appliance of high input-output characteristic.

At present, above-mentioned negative electrode and/or anode have and contain the lip-deep formation that layer is formed at collector body (metal forming etc.) to an active material that comprises each electrode active material, adhesive (synthetic resin etc.) and conductive auxiliary agent etc.

But; So far, electrically contacting between electrode active material and conductive auxiliary agent is abundant inadequately, so in the electrode of making; Between the active material particle or the resistance between collector body and the active material particle become big, thereby can not obtain high input-output characteristic.In order to solve such problem, the positive active material (such as with reference to TOHKEMY 2005-174586 communique and TOHKEMY 2004-14519 communique) such as the relation (ratio and configuration relation etc.) that limits active material and conductive auxiliary agent has been proposed.

Yet; Even state in the use under the situation of the positive active material of being put down in writing in TOHKEMY 2005-174586 communique and the TOHKEMY 2004-14519 communique; Aspect the charge-discharge characteristic rapidly of electrochemical appliance, also be difficult to obtain fully satisfied characteristic.

Summary of the invention

The present invention makes in view of the problem that exists in the above-mentioned prior art, and purpose is to provide active material particle for electrode and the electrode and the electrochemical appliance that uses it of the electrochemical appliance of the electrochemical appliance that can realize having excellent charge-discharge characteristic rapidly.

In order to achieve the above object; The present invention provides a kind of active material particle for electrode; It contains active material main body and the conductive auxiliary agent that partly covers the surperficial of this active material main body and have electronic conductivity; On the surface of above-mentioned active material main body, be formed with the projection that forms by above-mentioned conductive auxiliary agent, the height from above-mentioned active material body surfaces of above-mentioned projection be above-mentioned active material main body particle diameter 5～30%.

At present; As putting down in writing in the above-mentioned TOHKEMY 2004-14519 communique; Though the technology of the coverage rate of the conductive auxiliary agent that is defined in the active material body surfaces is arranged; But this technology is the technology that covers the active material body surfaces with conductive auxiliary agent equably, and in such active material particle that obtains, the conductive auxiliary agent electrical connection each other with electronic conductivity is abundant inadequately.Therefore, form under the situation of electrode, can not construct effective conductive network each other, cause internal resistance to increase, to such an extent as to be difficult to fully satisfy the charge-discharge characteristic rapidly of electrochemical appliance at active material particle using this active material particle.

To this; According to active material particle of the present invention; Owing on the surface of active material main body, have the projection of the above-mentioned height that forms by conductive auxiliary agent, when forming electrode, compare with the situation that does not have projection; The probability that the surface of the projection of an active material particle and another active material particle or projection electrically contact between active material particle improves, and can construct effective conductive network each other at active material particle.Therefore, constitute electrode and electrochemical appliance, can improve the conductivity of electrode interior tremendously, thereby can fully reduce internal resistance, improve the charge-discharge characteristic rapidly of electrochemical appliance through using this active material particle.

In the present invention, the so-called projection that is formed by conductive auxiliary agent is, concentrates on the active material body surfaces to conductive auxiliary agent part property and the projection that forms.In addition, be under the situation about layeredly forming in the covering part that is formed by the conductive auxiliary agent that covers the active material body surfaces, the meaning of projection is outstanding part from the surface of the covering part of this stratiform.Having or not of this projection can be confirmed through the SEM photo of active material particle.

In addition, in active material particle for electrode of the present invention, the above-mentioned active material main body of the preferred directly covering of above-mentioned conductive auxiliary agent.Thus, can improve electrically contacting of active material main body and conductive auxiliary agent.

In addition, in active material particle for electrode of the present invention, preferred above-mentioned projection has voidage greater than the zone in the voidage of above-mentioned active material main body side in its tip side.At this, projection has voidage greater than the meaning in the zone of the voidage of active material main body side to be in its tip side, and is less in the space occupancy (amount of the conductive auxiliary agent of per unit volume) of the conductive auxiliary agent of the tip side of projection.Because projection has the bigger zone of such voidage in tip side; On the top of projection with when other active material particle or conductive auxiliary agent contact; The shape on projection top is easily corresponding to the shape of other active material particles and conductive auxiliary agent and be out of shape, so be favourable aspect active material particle the combining closely property each other.Therefore, can construct more effectively conductive network each other at active material particle.

The present invention also provides a kind of electrode; This electrode with a kind of active material particle for electrode as constituent material; This active material particle for electrode comprises the conductive auxiliary agent that the active material main body covers the surface of this active material main body with part and has electronic conductivity; On the surface of above-mentioned active material main body, be formed with the projection that constitutes by above-mentioned conductive auxiliary agent, the height from the surface of above-mentioned active material main body of above-mentioned projection be above-mentioned active material main body particle diameter 5～30%.

According to kind electrode; Through contain play above-mentioned effect active material particle for electrode of the present invention as constituent material; Thereby can fully reduce internal resistance, under the situation that the electrode as electrochemical appliance uses, charge-discharge characteristic is very excellent rapidly can to make it.

The present invention further provides a kind of electrochemical appliance; The dielectric substrate that this electrochemical appliance has anode (anode), negative electrode (cathode) and has ionic conductivity; Has the structure that above-mentioned anode and above-mentioned negative electrode are situated between and are disposed relatively by above-mentioned dielectric substrate simultaneously; At least one side in above-mentioned anode and the above-mentioned negative electrode is contained with the electrode of a kind of active material particle for electrode as constituent material; This active material particle for electrode comprises the conductive auxiliary agent that the active material main body covers the surface of this active material main body with part and has electronic conductivity; On the surface of above-mentioned active material main body, be formed with the projection that constitutes by above-mentioned conductive auxiliary agent, the height from above-mentioned active material body surfaces of this projection be above-mentioned active material main body particle diameter 5～30%.

According to this electrochemical appliance, be used in anode and/or negative electrode through the electrode of the present invention that will play above-mentioned effect, thereby can obtain excellent charge-discharge characteristic rapidly.Also have; In this manual; So-called " anode (anode) " be polarity during with the discharge of electrochemical appliance as the anode (negative pole) of benchmark, so-called " negative electrode (cathode) " is that polarity during with the discharge of electrochemical appliance is as the negative electrode (positive pole) of benchmark.

The present invention further provides a kind of manufacturing approach of electrode; The manufacturing approach of this electrode has the operation that active material particle for electrode and adhesive and conductive auxiliary agent are mixed mutually; This active material particle for electrode comprises the conductive auxiliary agent that the active material main body covers the surface of this active material main body with part and has electronic conductivity; On the surface of above-mentioned active material main body, be formed with the projection that constitutes by above-mentioned conductive auxiliary agent, the height from above-mentioned active material body surfaces of above-mentioned projection be above-mentioned active material main body particle diameter 5～30%.

According to the present invention, active material particle for electrode and the electrode and the electrochemical appliance that uses it of the electrochemical appliance of the electrochemical appliance that can realize having excellent charge-discharge characteristic rapidly can be provided.

Description of drawings

Fig. 1 is the schematic section of the major part of expression active material particle of the present invention.

Fig. 2 is the schematic section of the major part of expression active material particle of the present invention.

Fig. 3 is the schematic section of a preferred execution mode of expression electrode of the present invention.

Fig. 4 is the front elevation of a preferred execution mode of expression electrochemical appliance of the present invention.

Fig. 5 is the expanded view when the normal to a surface direction of anode 10 is observed the inside of electrochemical appliance shown in Figure 4.

Fig. 6 is the schematic section when cutting off electrochemical appliance shown in Figure 4 along the X1-X1 line of Fig. 4.

Fig. 7 is the schematic section of the major part of expression when cutting off electrochemical appliance shown in Figure 4 along the X2-X2 line of Fig. 4.

The schematic section of the major part of Fig. 8 when to be expression along the Y-Y line of Fig. 4 cut off the represented electrochemical appliance of Fig. 4.

Fig. 9 is the schematic section of expression as an example of the basic comprising of the film of the constituent material of the shell of the represented electrochemical appliance of Fig. 4.

Figure 10 is the schematic section of expression as another example of the basic comprising of the film of the constituent material of the shell of the represented electrochemical appliance of Fig. 4.

Figure 11 is the SEM photo (multiplying power is 30,000 times) of the active material particle of embodiment 1.

Figure 12 is active material main body and the SEM photo (multiplying power is 30,000 times) of conductive auxiliary agent in existing electrode.

Figure 13 is the photo that the part of SEM photo of the active material particle of embodiment 1 that Figure 11 is represented has been amplified.

(A)～(C) of Figure 14 is the sketch map that the expression microelectrode is measured system.

Figure 15 is discharge and recharge rate and the chart of time relation of expression when being discharged and recharged by the constant potential of embodiment 1 resulting active material particle.

Embodiment

Below be as the case may be on one side with reference to accompanying drawing, with regard to of the present invention preferred embodiment do detailed explanation on one side.Also have, to identical or considerable part mark prosign, omit repeat specification in the accompanying drawing.In addition, the dimension scale of accompanying drawing is not limited to illustrated ratio.

(active material particle)

Active material particle of the present invention comprises the conductive auxiliary agent that the active material main body covers the surface of this active material main body with part and has electronic conductivity; On the surface of above-mentioned active material main body, be formed with the projection that constitutes by above-mentioned conductive auxiliary agent, the height from the surface of above-mentioned active material main body of above-mentioned projection be above-mentioned active material main body particle diameter 5～30%.

At this, having or not of above-mentioned projection can be by SEM (the ScaningElectron Micro Scope: photo affirmation scanning electron microscope) of active material particle.In the present invention, in the SEM photo of the active material particle of taking 10 places with 30000 times multiplying power arbitrarily, there is 1 in the photo in average per 1 place (1) when above, is judged as " projection is arranged ".Also have, in above-mentioned projection, also can sneak into the fine-powder of active material main body.

The viewpoint of the probability that electrically contacts each other from a plurality of active material particles of abundant raising, the height from the active material body surfaces of this projection must be this active material main body particle diameter 5～30%.More detailed, viewed whole projections in the SEM photo for above-mentioned any 10 places, the height of establishing projection is A, the particle diameter of establishing the active material main body that is formed with this projection is D (unit is identical with A), obtains by following formula:

R＝(A/D)×100

During the value of the height of represented projection and the ratio R (%) of the particle diameter of active material main body, its maximum R _Max(%) be necessary for 5～30%.If this R _MaxValue less than 5%, constructing under the situation of the electrical conductivity passage between a plurality of active material particles, so because the low tendency that is difficult to set up effective passage that has of projection as electrode; If this R _MaxValue surpassed 30%, constructing under the situation of the electrical conductivity passage between a plurality of active material particles as electrode so, because the too high resistance that just has of projection becomes easily big tendency.In addition, from same viewpoint, the maximum R of the height of projection and the ratio of the particle diameter of active material main body _MaxBe preferably 6～28%, be preferably 7～13% especially.Also have, the meaning of the particle diameter of above-mentioned active material main body is the minor axis diameter of being tried to achieve by SEM.In addition; From between a plurality of active material particles, constructing the more effectively viewpoint of electrical conductivity passage; Preferably in the SEM photo in above-mentioned any 10 places among observed all projections; The value of above-mentioned R is that 5～30% projection exists more than 5, is more preferably to exist more than 10.

Fig. 1 and Fig. 2 are the schematic sections of the major part of expression active material particle of the present invention.In the active material particle of Fig. 1 and Fig. 2, the surface of active material main body 4 is covered by conductive auxiliary agent 6 parts, and the projection 8 that is made up of conductive auxiliary agent 6 is formed on the surface of active material main body 4.Also have, in the active material particle of Fig. 1, covering part forms stratiform by conductive auxiliary agent 6, and this covering part surface forms projection 8 highlightedly certainly.

In Fig. 1 and Fig. 2; The shape of the projection in the active material particle of the present invention is preferably; Make the ratio (A/B) of length B on all and active material main body 4 contacted limits (base) of height A and the covering part of projection 8 become 1/30～30 shape, be more preferably and make it become 1/10～5 shape.When to when viewed all projections are obtained this value than (A/B) in the SEM photo in above-mentioned any 10 places, preferably its maximum is in above-mentioned scope.Surpass above-mentioned ratio if the height A of projection 8 is big, projection 8 becomes long so, constructs under the situation of the electrical conductivity passage between a plurality of active material particles as electrode, just has resistance and becomes big tendency easily.And if the length B on base surpasses above-mentioned ratio greatly, projection 8 will become too small so, constructs under the situation of the electrical conductivity passage between a plurality of active material particles as electrode, has the tendency that is difficult to set up effective passage.

In addition, active material particle of the present invention preferably has 10～80% the pantostrat that is made up of conductive auxiliary agent on the surface that covers the active material main body.The ratio of this pantostrat is specifically tried to achieve by following method.Promptly; Take the SEM photo of the active material particle in 10 places arbitrarily with 30000 times multiplying powers; On 1 place (1 's) photo, mark the grid of 1 μ m * 1 μ m; In the visual field of this 1 μ m * 1 μ m, try to achieve in the active material main body and be attached to that maximum in its total area of conductive auxiliary agent connects and the ratio of continuous conductive auxiliary agent area occupied, calculate the mean value that adds up to 120 visuals field ratio as the pantostrat of the conductive auxiliary agent in active material particle.

The ratio of above-mentioned pantostrat is preferably 10～80%, is more preferably 15～50%, is preferably 20～45% especially.If the ratio of this pantostrat is less than above-mentioned scope; Compare with the situation of ratio in above-mentioned scope of pantostrat so, when constituting electrochemical appliance, be difficult in electrode, form effective conductive network; Make internal resistance increase, thereby have and reduce the tendency of charge-discharge characteristic rapidly.And if the ratio of pantostrat is compared with the situation of ratio in above-mentioned scope of pantostrat greater than above-mentioned scope so, have the tendency that area that the insertion that can carry out lithium ion deviates from etc. reduces, this is not preferred.

In addition, in active material particle of the present invention, be preferably 20～90%, be more preferably 30～80%, be preferably 40～70% especially by the coverage rate of the active material main body of conductive auxiliary agent decision.If this coverage rate is less than 20%; Compare with the situation of coverage rate in above-mentioned scope so, when constituting electrochemical appliance, the probability that a plurality of active material particles are electrical contact with each other in electrode will reduce; Internal resistance will increase, thereby the tendency of charge-discharge characteristic reduction is rapidly arranged.On the other hand; If coverage rate surpasses 90%; Compare with the situation of coverage rate in above-mentioned scope so; Carried out lithium ion on the active material body surfaces deviate from and the area of the desorption of insertion and electrolyte ion and absorption etc. reduces, reduce the tendency of charge-discharge characteristic rapidly thereby have.

At this, the coverage rate that depends on conductive auxiliary agent of active material main body is that conductive auxiliary agent covers the ratio of active material main body in active material particle, specifically is to be tried to achieve by following method.Promptly; Take the SEM photo of the active material particle in 10 places arbitrarily with 30000 times multiplying powers; On 1 place (1 's) photo, mark the grid of 1 μ m * 1 μ m; In the visual field of this 1 μ m * 1 μ m, obtain in active material main body and the ratio that is attached to the conductive auxiliary agent area occupied in its total area of conductive auxiliary agent, thereby calculate add up to 120 visuals field mean value as the coverage rate in the active material particle.

In addition, in active material particle for electrode of the present invention, 5～60% of the surface of preferred active material main body is not covered by conductive auxiliary agent and exposes, and be continuously.Below, call continuous the exposed division of this active material body surfaces " exposed division continuously ".Desorption and absorption of deviating from of lithium ion and insertion and electrolyte ion etc. takes place in active material particle easily through having above-mentioned continuous exposed division.The ratio of this continuous exposed division is preferably 5～60%, from obtaining the viewpoint of above-mentioned effect more fully, and more preferably 10～50%, be preferably 20～40% especially.

At this, the ratio of the continuous exposed division in the active material main body is, not covered by conductive auxiliary agent of active material main body and exposing and the ratio of continuous exposed division specifically is to be tried to achieve by following method.Promptly; Take the SEM photo of the active material particle in 10 places arbitrarily with 30000 times multiplying powers; On 1 place (1 's) photo, mark the grid of 1 μ m * 1 μ m; In the visual field of this 1 μ m * 1 μ m, try to achieve in the active material main body and be attached to that maximum in its total area of conductive auxiliary agent connects and the ratio of the exposed division area occupied of continuous active material particle, calculate the mean value that adds up to 120 visuals field as the ratio of exposed division continuously.

Active material main body as the constituent material that is used as active material particle of the present invention; Can do suitably selection according to the kind of the electrochemical appliance that is suitable for and the polarity of electrode, in each electrochemical appliance, can have no particular limits and use known electrode active material.Under the situation of active material particle as the constituent material of the anode in the secondary cell; As the active material main body, can enumerate such as: can inhale as emitting (insert or mix dedoping) graphite of lithium ion, difficult graphitized carbon, being prone to the material with carbon element of graphitized carbon and low temperature sintered carbon etc.; The metal that can close with lithiumation of Al, Si, Sn etc.; With SiO ₂, SnO ₂Deng oxide be the amorphous compound of main body; Lithium titanate (Li ₄Ti ₅O ₁₂) etc.In addition, under the situation that active material particle is used as the constituent material of the negative electrode in the secondary cell,, can enumerate such as cobalt acid lithium (LiCoO as the active material main body ₂), lithium nickelate (LiNiO ₂), lithium manganese spinel (LiMn ₂O ₄) and by general formula: LiNi _xMn _yCo _zO ₂(x+y+z=1) composite metal oxide, lithium vfanadium compound, the V of expression ₂O ₅, olivine-type LiMPO ₄(wherein, M representes Co, Ni, Mn or Fe or their composition metal), lithium titanate (Li ₄Ti ₅O ₁₂) etc.In addition; Under the situation of active material particle as the constituent material use of the electrode in the electrochemical capacitor; As the active material main body; Can enumerate such as the granular or fibrous activated carbon of having accomplished activation processing and metal oxide etc., especially preferably use the material of the high electric double layer capacity of cocoanut shell activated carbon, pitch class activated carbon and phenolic resins class activated carbon etc.

The average grain diameter of active material main body has no particular limits, and can do suitably to select according to the kind of the electrochemical appliance that is suitable for and the polarity of electrode.Under the situation of active material particle as the constituent material use of the anode in the secondary cell, the average grain diameter of preferred active material main body is 0.1～50 μ m, more is preferably 1～30 μ m.In addition, under the situation of active material particle as the constituent material use of the negative electrode in the secondary cell, the average grain diameter of preferred active material main body is 0.1～30 μ m, more preferably 1～20 μ m.Also have, under the situation of active material particle as the constituent material use of the electrode in the electrochemical capacitor, the average grain diameter of preferred active material main body is 0.1～50 μ m, more preferably 1～30 μ m.Be in the above-mentioned scope through the average grain diameter that makes the active material main body, can improve the active material density in the electrode, have the tendency that forms suitable emptying aperture shape simultaneously.

As the conductive auxiliary agent of the constituent material that is used as active material particle of the present invention, just there is not special qualification so long as have the material of electronic conductivity, can use known conductive auxiliary agent.Can enumerate such as the material with carbon element of the Delanium of carbon black class, high crystalline and native graphite etc. as this conductive auxiliary agent; The metal material of gold, platinum, copper, nickel, stainless steel and iron etc.; The mixture of above-mentioned material with carbon element and metal material; Electroconductive oxide as ITO etc.

The average primary particle diameter of conductive auxiliary agent has no particular limits, but preferred 0.01～10 μ m is more preferably 0.02～3 μ m.If this average primary particle diameter so just has the tendency that is difficult to form appropriate projection less than 0.01 μ m; If surpassed 10 μ m, the tendency that is difficult to suitably cover the active material body surfaces so just arranged.

In active material particle of the present invention, the average grain diameter of active material main body is preferably 5～5000 with the ratio (average primary particle diameter of the average grain diameter/conductive auxiliary agent of active material main body) of the average primary particle diameter of conductive auxiliary agent, and more preferably 10～1000.If this size ratio less than 5, so just has the tendency that is difficult to suitably cover the active material body surfaces,, the tendency that is difficult to form suitable projection is so just arranged if surpassed 5000.

In active material particle of the present invention, the active material main body was preferably volume ratio 100: 1～2: 1, more preferably 60: 1～5: 1 with the ratio of the content of conductive auxiliary agent.Ratio through making this content is in the above-mentioned scope, has the tendency that can suitably cover the active material body surfaces and form suitable projection.

In addition, active material particle of the present invention, also can further contain such as adhesive and solid electrolyte etc. as composition in addition as long as have above-mentioned active material main body and above-mentioned conductive auxiliary agent at least.Also have, from obtaining the viewpoint of effect of the present invention more fully, the preferred substantive ground of active material particle of the present invention only is made up of active material main body and conductive auxiliary agent.Contain at active material particle under the situation of adhesive, adhesive is because between active material main body and conductive auxiliary agent, so cause the rising of internal resistance easily.With respect to this, through in active material particle, not using adhesive etc. and conductive auxiliary agent directly is attached to the active material main body, thereby can reduce internal resistance more reliably, can improve the charge-discharge characteristic rapidly of electrochemical appliance more reliably.

Above-mentioned active material particle of the present invention is such as making through following method.Promptly; Can utilize by ball mill active material main body and conductive auxiliary agent are carried out dry process then in the method for heat-treating under the inert gas atmosphere, handle method that conductive auxiliary agent (carbon etc.) is adhered to respect to the active material main body, the precursor solution of active material main body and conductive auxiliary agent (carbon etc.) is mixed and the method for then under inert gas atmosphere, heat-treating etc. through the chemical vapor deposition of using fluidized bed reaction etc., thereby produce the active material particle that partly covers the surface of active material main body by conductive auxiliary agent.Also have, the manufacturing approach of active material particle is not limited to these methods.

In addition, when making active material particle, preferred regulate to create conditions wait the active material particle that satisfies the ratio condition of above-mentioned coverage rate and pantostrat with acquisition.Such as using ball mill etc. mechanically under the situation of mixed active material main body and conductive auxiliary agent; If undercompounding coverage rate so reduces easily; In addition; If over-mixed conductive auxiliary agent is so too evenly disperseed and reduced the ratio of pantostrat easily, therefore preferably the optimum condition in the two of the ratio that makes coverage rate and pantostrat becomes the scope of regulation is in this application mixed.

(electrode)

Being characterized as of electrode of the present invention: the active material particle for electrode that contains the invention described above is as constituent material.At this, electrode contains the structure of layer such as having on the collector body of conductivity the active material that forms the conductivity that comprises active material particle for electrode, also can not have collector body and only is made up of the constituent that comprises active material particle.

Fig. 3 is the schematic section of a preferred execution mode of expression electrode of the present invention.As shown in Figure 3, electrode 2 be by collector body 16 be formed at active material on this collector body 16 and contain layer 18 and constitute.

Collector body 16 so long as can fully carry out contains good conductor from layer 18 movement of electric charges to active material does not so just have special qualification, can use the collector body that is used for known electrochemical appliance.Such as, can enumerate the metal forming of copper and aluminium etc. as collector body 16.

Active material contains layer 18 and mainly is made up of the active material particle and the adhesive of the invention described above.Also have, contain in the layer 18 at active material and also can further contain conductive auxiliary agent.

As being used for the adhesive that active material contains layer 18; Can have no particular limits and use known adhesive, such as enumerating Kynoar (PVDF), polytetrafluoroethylene (PTFE), tetrafluoraoethylene-hexafluoropropylene copolymer (FEP), tetrafluoroethene-perfluorinated alkyl vinyl ether co-polymer (PFA), ethylene-tetrafluoroethylene copolymer (ETFE), polychlorotrifluoroethylene (PCTFE), ethene-one chlorotrifluoroethylcopolymer copolymer (ECTFE), gathering the fluororesin of ethylene fluoride (PVF) etc.The constituent material of not only bonding active material particle of this adhesive and the conductive auxiliary agent that adds as required etc. also helps the bonding of these constituent materials and collector body each other.

In addition; Except that above-mentioned, as adhesive such as the vinylidne fluoride rubber that also can use biasfluoroethylene-hexafluoropropylene class fluorubber (VDF-HFP class fluorubber), biasfluoroethylene-hexafluoropropylene-tetrafluoroethylene fluorubber (VDF-HFP-TFE class fluorubber), vinylidene-five fluorine propylene class fluorubber (VDF-PFP class fluorubber), vinylidene-five fluorine propylene-tetrafluoroethylene fluorubber (VDF-PFP-TFE class fluorubber), vinylidene-perfluoro methyl vinyl ether-tetrafluoroethylene fluorubber (VDF-PFMVE-TFE class fluorubber), vinylidene-chlorotrifluoroethylene class fluorubber (VDF-CTFE class fluorubber) etc.

Also have; Except that above-mentioned, as adhesive such as also using polyethylene, polypropylene, PETG, aromatic polyamide, cellulose, styrene butadiene ribber, isoprene rubber, butadiene rubber, ethylene propylene rubber etc.In addition, also can use the thermoplastic elastomer shape macromolecule of styrene butadiene styrene block copolymer, its hydrogenation thing, styrene ethylene butadienestyrene copolymer, styrene isoprene styrene block copolymer, its hydrogenation thing etc.Have again, advise 1 between also can using, 2-polybutadiene, ethylene vinyl acetate copolymer, propylene alpha-olefin (carbon number 2～12) copolymer etc.In addition, can also use electroconductive polymer.

As containing the conductive auxiliary agent that uses in the layer 18 at active material does not have special qualification as required, can enumerate and the same material of conductive auxiliary agent that uses as the constituent material of active material particle.

Contain in the layer 18 at active material, the content of active material particle is preferably that to contain layer 18 solid-state part total amount with active material be more than the 80 quality % of benchmark, more preferably more than the 90 quality %.If this content is less than 80 quality %, active material density will reduce so, has the tendency that energy density reduces.

When making electrode 2, at first each above-mentioned constituent is mixed, be scattered in the solvent of solubilized adhesive, form with coating fluid (slurry or lotion etc.) thereby make electrode.As long as can just not have special qualification by dissolved adhesive as solvent.As this ratio of solvent as enumerating N-methyl-2-pyrrolidone, N, N-diformamide etc.

Then, above-mentioned electrode formation is coated on the surface of collector body 16 with coating fluid, drying forms active material through calendering and contains layer 18 on collector body 16, accomplished the making of electrode 2.At this, the method that electrode is formed when coating collector body 16 surperficial with coating fluid does not have special qualification, as long as it is just passable to do suitable decision according to the material of collector body 16 and shape etc.As this coating process such as enumerating metal mask print process, electrostatic applications method, dip coating, spraying process, rolling method, scraping the skill in using a kitchen knife in cookery, intaglio plate rubbing method and silk screen print method etc.

(electrochemical appliance)

Being characterized as of electrochemical appliance of the present invention: possess anode, negative electrode and have the dielectric substrate of ionic conductivity; Have the structure that above-mentioned anode and above-mentioned negative electrode are situated between and are disposed relatively by above-mentioned dielectric substrate, at least one in above-mentioned anode and the above-mentioned negative electrode is the electrode of the invention described above.

Fig. 4 is the front elevation of a preferred execution mode (lithium rechargeable battery) of expression electrochemical appliance of the present invention.Also have, Fig. 5 is the expanded view when the normal to a surface direction of anode 10 sees that the represented electrochemical appliance of Fig. 4 is inner.Fig. 6 is the schematic section when the X1-X1 line of Fig. 4 cuts off electrochemical appliance shown in Figure 4.The schematic section of the major part that Fig. 7 is expression when the X2-X2 line of Fig. 4 cuts off electrochemical appliance shown in Figure 4.The schematic section of the major part that Fig. 8 is expression when the Y-Y line of Fig. 4 cuts off electrochemical appliance shown in Figure 4.

Like Fig. 4～shown in Figure 8, electrochemical appliance 1 mainly by relative to each other tabular anode 10 and tabular negative electrode 20, between anode 10 and negative electrode 20, be electrically connected in abutting connection with the tabular dividing plate 40 of configuration, the electrolyte solution (being non-aqueous electrolytic solution in this execution mode) that contains lithium ion, the container 50 that under air-tight state, holds them, end anode 10 simultaneously another end nipple from the anode of the outside of container 50 with lead 12, end be electrically connected on negative electrode 20 simultaneously another end nipple start from container 50 the negative electrode of outside with 22 formations of lead.

At this, at least one in anode 10 and the negative electrode 20 is above-mentioned electrode of the present invention 2.Also have, in lithium rechargeable battery, the lower tendency of conductivity of negative electrode is arranged generally, so preferred electrode of the present invention 2 is used in negative electrode 20 at least.In addition, do not use under the situation of electrode 2 of the present invention, can especially restrictedly not use present known anode 10 or negative electrode 20 as anode 10 or negative electrode 20.

In addition, the collector body of negative electrode 20 is electrically connected on such as the end of the negative electrode that is made up of aluminium with lead 22, and negative electrode extends to the outside of container 50 with an other end of lead 22.In addition, the collector body of anode 10 also is to be electrically connected on such as the end of the anode that is made up of copper or nickel with lead 12, and anode extends to the outside of container 50 with an other end of lead 12.

Be disposed at the dividing plate 40 between anode 10 and the negative electrode 20 as long as form the porous body that has ion permeability and have an electronic isolation property and so just not have special limiting, can use the dividing plate that is used for known electrochemical appliance.As this dividing plate 40 such as enumerating: the thin-film laminate that constitutes by polyethylene, polypropylene or polyalkenes hydrocarbon; The stretched PTFE film of above-mentioned high molecular mixture; Or by being selected from fabric nonwoven cloth that cellulose, polyester and polyacrylic at least a constituent material form etc.

Filling is in the inner space of container 50 for electrolyte solution (not having diagram), and its part is contained in the inside of anode 10, negative electrode 20 and dividing plate 40.Electrolyte solution uses and to be dissolved in organic solvent to lithium salts and the non-aqueous electrolytic solution that obtains.As lithium salts such as using LiPF ₆, LiClO ₄, LiBF ₄, LiAsF ₆, LiCF ₃SO ₃, LiCF ₃CF ₂SO ₃, LiC (CF ₃SO ₂) ₃, LiN (CF ₃SO ₂) ₂, LiN (CF ₃CF ₂SO ₂) ₂, LiN (CF ₃SO ₂) (C ₄F ₉SO ₂), LiN (CF ₃CF ₂CO) ₂Deng salt.Also have, these salt both can use a kind separately, also can be also with more than 2 kinds.In addition, thus electrolyte solution also can be done gel through adding macromolecule etc.

Can use the solvent that is used for known electrochemical appliance as organic solvent.Such as preferably enumerating propene carbonate, ethylene carbonate and diethyl carbonate etc.These organic solvents both can use separately also can with arbitrary proportion mix 2 kinds with on use.

Container 50 is to use mutually a pair of film (the 1st film 51 and the 2nd film 52) in opposite directions and forms.At this, as shown in Figure 5, the 1st film 51 and the 2nd film 52 in this execution mode link together.Promptly; Container 50 in this execution mode is through the folding rectangular-shaped film that is made up of a composite packing film at fold line X3-X3 place shown in Figure 5, and with 1 group of relative edge portion of rectangular-shaped film each other (51B of edge portion of the 1st film 51 among the figure and the 52B of edge portion of the 2nd film 52) overlapping and use adhesive or seal and form.Also have, 51A among Fig. 4 and Fig. 5 and the 52A among Fig. 5 represent the not bonding of the 1st film 51 and the 2nd film 52 or the subregion that does not seal respectively.

Then, the 1st film 51 and the 2nd film 52 represent to have when 1 rectangular-shaped film is folded with above-mentioned form the part of this film of face that can be relative to each other respectively.At this, in this manual, be referred to as " sealing " to the 1st film 51 after engaging and the edge portion separately of the 2nd film 52.

Thus, be provided for sealing that the 1st film 51 and the 2nd film 52 are engaged because there is no need part at fold line X3-X3, so can further reduce the sealing in the container 50.The volume that consequently can further improve with space that electrochemical appliance 1 should be set is the volume energy density of benchmark.

In addition; Like Fig. 4 and shown in Figure 5; In the situation of this execution mode; The anode that is connected in anode 10 is configured to lead 12 and the negative electrode that is connected in negative electrode 20 end separately with lead 22, and is outstanding to the outside from the sealing of the 52B of edge portion of the 51B of edge portion that engages the 1st above-mentioned film 51 and the 2nd film.

The film that constitutes the 1st film 51 and the 2nd film 52 is to have flexual film.The light filmization easily of film quality is so can process film like with the shape of electrochemical appliance self.Therefore, can easily improve original volume energy density, the volume that the while can easily improve with the space that should be provided with of electrochemical appliance is the volume energy density of benchmark.

This film does not just have special qualification so long as have flexual film; But from the sufficient mechanical of guaranteeing container and light weight prevent effectively simultaneously moisture and air from container 50 outsides to container 50 inner infiltrations and electrolyte ingredient from container 50 inside the viewpoint to container 50 outside dissipations; Preferably " composite packing film ", inner most layer that should " composite packing film " has the macromolecule system that is contacted with generating important document 60 at least and the metal level that is disposed at the opposition side of the contacted side of generating important document of innermost layer.

As the composite packing film that can be used as the 1st film 51 and the 2nd film 52, such as the composite packing film of enumerating Fig. 9 and structure shown in Figure 10.Metal level 50c on the inner most layer 50a that composite packing film 53 shown in Figure 9 has face F53 place within it and generating important document 60 contacted macromolecule systems and the another side (face in the outside) that is disposed at inner most layer 50a.In addition, composite packing film 54 shown in Figure 10 has the structure that on the face in the outside of the metal level 50c of composite packing film shown in Figure 9 53, has further disposed the outermost layer 50b of macromolecule system.

The composite packing film that can be used as the 1st film 51 and the 2nd film 52; So long as have the compound package material of the layer more than 2; So just there is not special qualification; The metal level of macromolecule layer more than 1 that it is representative that above-mentioned layer more than 2 possesses with above-mentioned inner most layer and metal forming etc.; But from obtaining the viewpoint with above-mentioned same effect more reliably; Preferred composite packing film 54 that kind shown in figure 10 are made up of the layer more than 3 layers, and this layer more than 3 layers comprises inner most layer 50a, from the outermost layer 50b of the macromolecule system of the inner most layer 50a outer surface side that is disposed at container 50 farthest and be disposed at least 1 metal level 50c between inner most layer 50a and the outermost layer of 50b.

Inner most layer 50a has flexual layer; Its constituent material so long as can show above-mentioned pliability and have with respect to employed non-aqueous electrolytic solution chemical stability (characteristic of chemical reaction, dissolving and expansion does not take place) and with respect to the macromolecule of the chemical stability of oxygen G&W (airborne moisture); So just do not have special qualification, but preferably have the low material of permeability the composition of oxygen, water (airborne moisture) and non-aqueous electrolytic solution.Such as thermoplastic resin of enumerating engineering plastics, polyethylene, polypropylene, poly sour modifier, polyacrylic sour modifier, polyethylene ion key polymer and polypropylene ion key polymer etc. etc.

Also have; The meaning of so-called " engineering plastics " is the plastics with excellent mechanical characteristic, thermal endurance and durability that use with aspects such as materials at mechanical part, electric component and dwelling house, such as enumerating polyacetals, polyamide, Merlon, gathering hydroxyl tetramethylene oxygen terephthalate (polybutylene terephthalate (PBT)), PETG, polyimides, polyphenylene sulfide etc.

In addition; Composite packing film 54 shown in figure 10; Except inner most layer 50a, when the layer of macromolecule system such as the outermost layer of picture 50b also is set, layer also can the using and the above-mentioned inner most layer of identical constituent material of 50a of this macromolecule system.

As metal level 50c, be preferably the layer that forms by the metal material that has for the corrosion resistance of oxygen, water (airborne moisture) and non-aqueous electrolytic solution.Such as using the metal forming that forms by aluminium, aluminium alloy, titanium and chromium etc.

The encapsulating method of all sealings in container 50 does not have special qualification, but from productive viewpoint, preferably uses the heat seal method.

Like Fig. 4 and shown in Figure 5; On the part of the contacted anode of sealing with lead 12 of the outer pack that constitutes with the 52B of edge portion, covered and be used for preventing that anode is with the metal level contacted insulator 14 of lead 12 with the composite packing film that constitutes each film by the 51B of edge portion of the 1st film 51 and the 2nd film 52.Also have; On the part of the contacted negative electrode of sealing with lead 22 of the outer pack that constitutes with the 52B of edge portion, covered and be used for preventing that negative electrode is with the metal level contacted insulator 24 of lead 22 with the composite packing film that constitutes each film by the 51B of edge portion of the 1st film 51 and the 2nd film 52.

The formation of these insulators 14 and insulator 24 does not have special qualification, such as being formed by macromolecule respectively.Also have, if can prevent fully that metal level and anode in the composite packing film from lead 12 and negative electrode each contact with lead 22, so also can form the formation that does not dispose these insulators 14 and insulator 24.

Below, such as making above-mentioned electrochemical appliance 1 according to following order.At first, respectively anode is electrically connected with each of lead 22 and anode 10 and negative electrode 20 with lead 12 and negative electrode., with state of contact (preferred unadhered state) dividing plate 40 be configured in anode 10 and negative electrode 20 between, and accomplish generating important document 60 thereafter.

Then, for example, make container 50 according to following method.At first, when constituting the 1st film and the 2nd film by above-mentioned composite packing film, the known manufacture method of using dry type composite algorithm, wet type composite algorithm, hot melt composite algorithm and extruding composite algorithm etc. is made.In addition, be ready to become film and the metal forming that forms by aluminium etc. of the layer of the macromolecule system that constitutes composite packing film.Such as preparing metal forming through the rolling processing metal material.

Then, preferably forming the mode of a plurality of layers above-mentioned formation, thereby on the film of the layer that becomes macromolecule system and the applying metal forming that is situated between by adhesive etc. produce composite packing film (plural layers).Then, cut off composite packing film, prepare 1 rectangular-shaped film with this according to the size of appointment.

Then; As previous with reference to Fig. 5 illustrated; Folding 1 film for example, uses sealer just on desired width, the sealing 51B (51B of edge portion) of the 1st film 51 and the sealing 52B (52B of edge portion) of the 2nd film 52 to be carried out heat seal with the heating condition of appointment.At this moment, the peristome in order to ensure being used for generating important document 60 is imported to container 50 is provided with a part and does not implement thermosealed part.Obtained having the container 50 of the state of peristome thus.

Then, the inside that the generating important document 60 that anode has been electrically connected with lead 22 with lead 12 and negative electrode inserts the container 50 of the state with peristome.Inject electrolyte solution then.Then, anode is being inserted into respectively under the state in the container 50 with lead 12 and the negative electrode part with lead 22, is using sealer that the peristome of container 50 is sealed.So accomplished the making of container 50 and electrochemical appliance 1.In addition, electrochemical appliance of the present invention is not limited to the device of shape like this, also can be the shape of cylindrical shape etc.

More than done detailed explanation with regard to a preferred execution mode of electrochemical appliance of the present invention, but the present invention is not limited to above-mentioned execution mode.Such as, in the explanation of above-mentioned execution mode, also can form compacter formation through the sealing of folding electrochemical appliance 1.In addition; In the explanation of above-mentioned execution mode; Electrochemical appliance 1 with regard to possessing each 1 anode 10 and negative electrode 20 respectively is described, but also can form anode 10 and negative electrode 20 that possesses respectively more than 1 and the formation that always between anode 10 and negative electrode 20, disposes 1 dividing plate 40.

In addition such as; In the explanation of above-mentioned execution mode; Be that the situation of lithium rechargeable battery is described mainly with regard to electrochemical appliance; But electrochemical appliance of the present invention is not limited to lithium rechargeable battery; Also can be the secondary cell except lithium rechargeable battery that waits of lithium metal secondary battery (use electrode of the present invention at negative electrode, use the secondary cell of lithium metal at anode) and the electrochemical capacitor of double electric layer capacitor, simulation capacity capacitor, plan electric capacity (Pseudo-Capacitor) and redox capacitor etc. etc.In addition, electrochemical appliance of the present invention also can be used in the micromachine, IC-card etc. of self-action power supply, be configured on the printed circuit substrate or be disposed at the purposes of the decentralized power s in the printed circuit substrate.Also have, in the situation of the electrochemical appliance except that lithium rechargeable battery, as active material particle, as long as use is suitable for each electrochemical appliance.

Embodiment

Followingly come more specifically to explain the present invention, but the present invention is not limited to following embodiment according to embodiment and comparative example.

(embodiment 1)

Will be as the LiFePO of the average grain diameter 3 μ m of active material main body ₄Carry out dry process 1 hour with 90: 10 mixed proportion of mass ratio with ball mill with acetylene black as the average primary particle diameter 80nm of conductive auxiliary agent; Further under Ar atmosphere 500 ℃ of heat treatments of carrying out 1 hour, so obtain giving conductive auxiliary agent at the active material particle on the active material main body.

< observation of SEM photo >

Take the SEM photo of the active material particle that is obtained in any 10 places with 30000 times multiplying power; In 1 place (1 's) photo, mark the grid of 1 μ m * 1 μ m; In the visual field of this each 1 μ m * 1 μ m, try to achieve the coverage rate of the conductive auxiliary agent that is covered with active material and the ratio of pantostrat, and calculate the mean value in all visuals field.In addition, in the SEM in above-mentioned any 10 places photo, the having or not of the projection on the covering part surface of having confirmed to form by conductive auxiliary agent.In the SEM in 10 places photo, measure the number of observed projection; With the projection number of the photo in average per 1 place is that situation more than 1 has been judged as projection, and the projection number of the photo in average per 1 place is judged as no projection less than 1 situation.Its result is shown in below table 1.

In addition, 1 of SEM photo of the active material particle of expression embodiment 1 in Figure 11.In Figure 11, can confirm that conductive auxiliary agent 6 parts have covered the surface of active material main body 4.Also have, can confirm on the covering part surface that constitutes by conductive auxiliary agent 6, to be formed with projection 8.In addition, expression has been taken active material main body, conductive auxiliary agent, adhesive and solvent has been mixed active material main body and the conductive auxiliary agent in the existing electrode that the slurry that obtains is coated on the collector body and form and the SEM photo that obtains mutually in Figure 12.In Figure 12, compare with active material particle shown in Figure 11, can confirm that conductive auxiliary agent 6 does not cover the surface of active material main body 4 basically, can confirm also not form projection.

Figure 13 is the photo that has amplified by the part of the SEM photo of active material particle shown in Figure 11.Shown in this SEM photo, try to achieve the height A of projection 8 and the maximum R of the ratio of the particle diameter D of active material main body 4 _Max(%).In addition, in the SEM photo in above-mentioned 10 places arbitrarily, try to achieve the maximum of ratio (A/B) of the length B on all and limit (base) that active material main body 4 is joined of height A and the covering part of projection 8.Its result is shown in below table 1.

< mensuration of the constant potential charge-discharge characteristic of active material particle >

In Figure 14, be illustrated in employed microelectrode in this mensuration and measure the skeleton diagram of system.Figure 14 (A) is entire system figure, and Figure 14 (B) is the enlarged drawing of test trough, and Figure 14 (C) is the enlarged drawing of the contact portion of active material particle and microelectrode.

Shown in figure 14, the microscopic system that loads test trough 70 is positioned over above the shock-absorbing platform 72, and is arranged in the glove box (main tank) that is full of with dry argon gas (dew point-80 ℃ below).Test trough 70 is stainless steels, and is set on the microscopical observation platform 74.After coating the PVDF slurry on the PET film 92; Sprinkle active material particle 82 by above-mentioned acquisition, and dry, utilize PVDF layer 94 that active material particle 82 is fixed on the PET film 92 thus; This is cut into the area of appointment and is arranged at stainless steel test trough 70 bottoms, inject LiPF ₆/ PC is as electrolyte 84.

Observe the image that is installed on the CCD camera 80 on the microscope 78 on one side; Operate microoperation device 76 on one side; Make microelectrode 88 (diameter d=10 μ m) thus front end contact with active material particle 82 to establish and electrically contact; Microelectrode 88 is made into through enclosing metal wire 86 in the glass and grind front end, implements the charging of 4.5V constant potential, 2.5V constant potential discharge mensuration with the lithium benchmark of reference electrode 90.Its result is shown among Figure 15.Figure 15 is discharge and recharge rate and the figure of time relation of expression constant potential when discharging and recharging.By so measuring, try to achieve the time that arrives till 80% charging, 80% is discharged, relatively the charge-discharge characteristic rapidly of active material particle.At this moment, 100% the capacity of the reversible capacity of trying to achieve as active material particle by the cyclic voltammetry of 0.2mV/s.Its result is shown in the table 1.

< evaluation of electrode characteristic >

Will be by the active material particle (93 mass parts) of above-mentioned acquisition, mix as the carbon black (3 mass parts) of conductive auxiliary agent and as the PVDF (4 mass parts) of adhesive, and be scattered in N-methyl-2-pyrrolidone (NMP) thus in the modulation active material contain the slurry that layer forms usefulness.This slurry is coated on the aluminium foil as collector body, after drying, rolled, thereby obtain to contain the electrode on layer collector body that is formed at thickness 20 μ m to the active material of thickness 40 μ m.Then, the dividing plate that forms by polyethylene be held on resulting electrode and as between its Li paper tinsel (thickness 100 μ m) to electrode and carry out range upon range of, thereby obtain duplexer (plain body).This duplexer is put into the aluminum laminated bag, will be as the 1MLiPF of electrolyte ₆/ PC carries out vacuum seal after injecting this aluminum laminated bag, so just be made into the electrode evaluation with battery (long 48mm, wide 34mm, thick 2mm).Execution is carried out the rate characteristic evaluation to the test that discharges and recharges of this battery, relatively the charge-discharge characteristic rapidly of electrode.The evaluation of this electrode characteristic (sudden discharge characteristic) is carried out according to following method: utilize the charging of 1C constant current constant voltage under off voltage, to discharge till the discharge off voltage with 1C after the full charging; Discharge till the discharge off voltage with 5C after full again the charging, thereby obtained the capacity of 5C discharge and the ratio of the capacity that 1C discharges [(capacity that capacity/1C of 5C discharge discharges) * 100] thereafter.At this, be referred to as the 1C ratio to the full capacity of the battery that will try to achieve by the electrode active material amount with the magnitude of current of the degree of 1 hour discharge (charging), represent its magnitude of current with the C ratio several times.In addition, as present embodiment, use LiFePO as the active material main body ₄Situation in, charged side is broken off with 4.5V and being charged, the discharge side is broken off with 2.5V and being discharged.On the other hand, of the back, using Li as the active material main body ₄Ti ₅O ₁₂Situation under, charged side is broken off with 0.8V and being charged, the discharge side is broken off with 2.2V and being discharged.Its result is shown in table 1.

(embodiment 2)

For LiFePO as the average grain diameter 3 μ m of active material main body ₄, in fluidized bed reaction, chemical species are used toluene and carry out the chemical vapor deposition processing of charcoal, LiFePO ₄Be adjusted to 90: 10 with the mass ratio of carbon, thereby obtain to give the active material particle on the active material main body conductive auxiliary agent (carbon).

For the active material particle that is obtained, with carry out with embodiment 1 identical step that the SEM photo is observed, the mensuration of the constant potential charge-discharge characteristic of active material particle and use active material particle to make the characteristic of electrode evaluation that obtains.Its result is shown in table 1.

(embodiment 3)

With FeSO ₄7H ₂O, H ₃PO ₄And LiOH is dissolved in the pure water, and the hydro-thermal of under 150 ℃, carrying out 4 hours is synthetic, thereby obtains the LiFePO as the average grain diameter 0.5 μ m of active material main body ₄With this LiFePO ₄With as the sucrose solution of carbon predecessor with LiFePO ₄The mode that becomes 90: 10 with the mass ratio of carbon is mixed, under Ar atmosphere 800 ℃ of heat treatments of carrying out 1 hour, thereby obtain to give the active material particle on the active material main body conductive auxiliary agent (carbon).

(embodiment 4)

Will be as the Li of the average grain diameter 3 μ m of active material main body ₄Ti ₅O ₁₂Carry out dry process 1 hour with 90: 10 mixed proportion of mass ratio by ball mill with acetylene black as the average primary particle diameter 80nm of conductive auxiliary agent; Further under Ar atmosphere, heat-treat 1 hour, so obtain on the active material main body, having given the active material particle of conductive auxiliary agent at 500 ℃.

For the active material particle that is obtained, observe to carry out the SEM photo with embodiment 1 identical step.In addition, the mensuration of the constant potential charge-discharge characteristic of active material particle and use active material particle to make the characteristic of electrode evaluation that obtains, except charging potential with 2.2V, discharge potential with the 0.8V other to carry out with embodiment 1 identical step.Its result is shown in table 1.

(comparative example 1)

Will be as the LiFePO of the average grain diameter 3 μ m of active material main body ₄Carry out dry process 5 minute with 90: 10 mixed proportion of mass ratio by ball mill with acetylene black as the average primary particle diameter 80nm of conductive auxiliary agent; Further in Ar atmosphere, heat-treat 1 hour, so obtain on the active material main body, having given the active material particle of conductive auxiliary agent at 500 ℃.

(comparative example 2)

For LiFePO as the average grain diameter 3 μ m of active material main body ₄, in fluidized bed reaction, the chemical vapor deposition that chemical species use toluene to carry out charcoal is handled, be adjusted to LiFePO ₄Become 99.5: 0.5 with the mass ratio of carbon, thereby obtain on the active material main body, to have given the active material particle of conductive auxiliary agent (carbon).

(comparative example 3)

Will be as the LiFePO of the average grain diameter 3 μ m of active material main body ₄Carry out dry process 1 hour with 90: 10 mixed proportion of mass ratio by ball mill with graphite as the average grain diameter 3 μ m of conductive auxiliary agent; Further in Ar atmosphere, heat-treat 1 hour, so obtain on the active material main body, having given the active material particle of conductive auxiliary agent at 500 ℃.

[table 1]

	Active material: conductive auxiliary agent (mass ratio)	The SEM photo is observed					The constant potential charge-discharge characteristic of active material particle		Electrode characteristic
										Coverage rate/%	Ratio/the % of pantostrat	Have or not projection	R _max/ ％	A/B	80% the charging interval/second	80% the discharge time/second	Rate characteristic (5C/1C)/%
		Embodiment
1	90∶10		45	22.5	Have	18	0.67	38	57	98
		Embodiment 2									90∶10	64	51.2	Have	7	0.17	23	39	100
Embodiment 3	90∶10		58	40.6	Have	27	1.8	28	48	100
		Embodiment 4									90∶10	41	12.3	Have	13	1.3	18	58	97
Comparative example 1	90∶10		13	1.3	Do not have	-	-	145	218	43
		Comparative example 2									99.5∶0.5	4	0.2	Do not have	-	-	900	1770	9
Comparative example 3	90∶10		17	2.6	Do not have	-	-	112	180	56

(embodiment 5)

Will be as the LiFePO of the average grain diameter 3 μ m of active material main body ₄Carry out dry process 59 minute with 90: 10 mixed proportion of mass ratio by ball mill with acetylene black as the average primary particle diameter 80nm of conductive auxiliary agent; Further in Ar atmosphere, heat-treat 48 minutes, so obtain on the active material main body, having given the active material particle of conductive auxiliary agent at 500 ℃.

(embodiment 6)

Will be as the LiFePO of the average grain diameter 3 μ m of active material main body ₄Carry out dry process 47 minute with 90: 10 mixed proportion of mass ratio by ball mill with acetylene black as the average primary particle diameter 80nm of conductive auxiliary agent; Further in Ar atmosphere, heat-treat 40 minutes, so obtain on the active material main body, having given the active material particle of conductive auxiliary agent at 500 ℃.

(embodiment 7)

Will be as the LiFePO of the average grain diameter 3 μ m of active material main body ₄Carry out dry process 52 minute with 90: 10 mixed proportion of mass ratio by ball mill with acetylene black as the average primary particle diameter 80nm of conductive auxiliary agent; Further in Ar atmosphere, heat-treat 35 minutes, so obtain on the active material main body, having given the active material particle of conductive auxiliary agent at 500 ℃.

(embodiment 8)

Will be as the LiFePO of the average grain diameter 3 μ m of active material main body ₄Carry out dry process 45 minute with 90: 10 mixed proportion of mass ratio by ball mill with acetylene black as average primary particle diameter 1 50nm of conductive auxiliary agent; Further in Ar atmosphere, heat-treat 2 hours, so obtain on the active material main body, having given the active material particle of conductive auxiliary agent at 500 ℃.

(embodiment 9)

Will be as the LiFePO of the average grain diameter 3 μ m of active material main body ₄Carry out dry process 55 minute with 90: 10 mixed proportion of mass ratio by ball mill with acetylene black as the average primary particle diameter 150nm of conductive auxiliary agent; Further in Ar atmosphere, heat-treat 1 hour, so obtain on the active material main body, having given the active material particle of conductive auxiliary agent at 500 ℃.

(embodiment 10)

Will be as the LiFePO of the average grain diameter 3 μ m of active material main body ₄Carry out dry process 46 minute with 90: 10 mixed proportion of mass ratio by ball mill with acetylene black as the average primary particle diameter 80nm of conductive auxiliary agent; Further in Ar atmosphere, heat-treat 70 minutes, so obtain on the active material main body, having given the active material particle of conductive auxiliary agent at 500 ℃.

(embodiment 11)

Will be as the LiFePO of the average grain diameter 3 μ m of active material main body ₄Carry out dry process 55 minute with 90: 10 mixed proportion of mass ratio by ball mill with acetylene black as the average primary particle diameter 80nm of conductive auxiliary agent; Further in Ar atmosphere, heat-treat 57 minutes, so obtain on the active material main body, having given the active material particle of conductive auxiliary agent at 500 ℃.

(embodiment 12)

Will be as the LiFePO of the average grain diameter 3 μ m of active material main body ₄Carry out dry process 55 minute with 90: 10 mixed proportion of mass ratio by ball mill with acetylene black as the average primary particle diameter 80nm of conductive auxiliary agent; Further in Ar atmosphere, heat-treat 45 minutes, so obtain on the active material main body, having given the active material particle of conductive auxiliary agent at 500 ℃.

(embodiment 13)

Will be as the LiFePO of the average grain diameter 3 μ m of active material main body ₄Carry out dry process 65 minute with 90: 10 mixed proportion of mass ratio by ball mill with acetylene black as the average primary particle diameter 80nm of conductive auxiliary agent; Further in Ar atmosphere, heat-treat 1 hour, so obtain on the active material main body, having given the active material particle of conductive auxiliary agent at 400 ℃.

(embodiment 14)

Will be as the LiFePO of the average grain diameter 3 μ m of active material main body ₄Carry out dry process 72 minute with 90: 10 mixed proportion of mass ratio by ball mill with acetylene black as the average primary particle diameter 80nm of conductive auxiliary agent; Further in Ar atmosphere, heat-treat 50 minutes, so obtain on the active material main body, having given the active material particle of conductive auxiliary agent at 400 ℃.

(embodiment 15)

Will be as the LiFePO of the average grain diameter 3 μ m of active material main body ₄Carry out dry process 79 minute with 90: 10 mixed proportion of mass ratio by ball mill with acetylene black as the average primary particle diameter 80nm of conductive auxiliary agent; Further in Ar atmosphere, heat-treat 40 minutes, so obtain on the active material main body, having given the active material particle of conductive auxiliary agent at 400 ℃.

(embodiment 16)

Will be as the LiFePO of the average grain diameter 3 μ m of active material main body ₄Carry out dry process 45 minute with 90: 10 mixed proportion of mass ratio by ball mill with acetylene black as the average primary particle diameter 50nm of conductive auxiliary agent; Further in Ar atmosphere, heat-treat 50 minutes, so obtain on the active material main body, having given the active material particle of conductive auxiliary agent at 500 ℃.

(embodiment 17)

Will be as the LiFePO of the average grain diameter 3 μ m of active material main body ₄Carry out dry process 82 minute with 90: 10 mixed proportion of mass ratio by ball mill with acetylene black as the average primary particle diameter 50nm of conductive auxiliary agent; Further in Ar atmosphere, heat-treat 1 hour, so obtain on the active material main body, having given the active material particle of conductive auxiliary agent at 500 ℃.

(embodiment 18)

Will be as the LiFePO of the average grain diameter 3 μ m of active material main body ₄Carry out dry process 39 minute with 90: 10 mixed proportion of mass ratio by ball mill with acetylene black as the average primary particle diameter 80nm of conductive auxiliary agent; Further in Ar atmosphere, heat-treat 1 hour, so obtain on the active material main body, having given the active material particle of conductive auxiliary agent at 500 ℃.

(embodiment 19)

Will be as the LiFePO of the average grain diameter 3 μ m of active material main body ₄Carry out dry process 90 minute with 90: 10 mixed proportion of mass ratio by ball mill with acetylene black as the average primary particle diameter 80nm of conductive auxiliary agent; Further in Ar atmosphere, heat-treat 40 minutes, so obtain on the active material main body, having given the active material particle of conductive auxiliary agent at 500 ℃.

(embodiment 20)

Will be as the LiFePO of the average grain diameter 3 μ m of active material main body ₄Carry out dry process 94 minute with 90: 10 mixed proportion of mass ratio by ball mill with acetylene black as the average primary particle diameter 80nm of conductive auxiliary agent; Further in Ar atmosphere, heat-treat 30 minutes, so obtain on the active material main body, having given the active material particle of conductive auxiliary agent at 500 ℃.

(embodiment 21)

Will be as the LiFePO of the average grain diameter 3 μ m of active material main body ₄Carry out dry process 100 minute with 90: 10 mixed proportion of mass ratio by ball mill with acetylene black as the average primary particle diameter 80nm of conductive auxiliary agent; Further in Ar atmosphere, heat-treat 20 minutes, so obtain on the active material main body, having given the active material particle of conductive auxiliary agent at 500 ℃.

(embodiment 22)

Will be as the LiFePO of the average grain diameter 3 μ m of active material main body ₄Carry out dry process 55 minute with 90: 10 mixed proportion of mass ratio by ball mill with acetylene black as the average primary particle diameter 80nm of conductive auxiliary agent; Further in Ar atmosphere, heat-treat 48 minutes, so obtain on the active material main body, having given the active material particle of conductive auxiliary agent at 500 ℃.

(embodiment 23)

Will be as the LiFePO of the average grain diameter 3 μ m of active material main body ₄Carry out dry process 75 minute with 90: 10 mixed proportion of mass ratio by ball mill with acetylene black as the average primary particle diameter 80nm of conductive auxiliary agent; Further in Ar atmosphere, heat-treat 1 hour, so obtain on the active material main body, having given the active material particle of conductive auxiliary agent at 500 ℃.

(embodiment 24)

Will be as the LiFePO of the average grain diameter 3 μ m of active material main body ₄Carry out dry process 80 minute with 87.5: 12.5 mixed proportion of mass ratio by ball mill with acetylene black as the average primary particle diameter 80nm of conductive auxiliary agent; Further in Ar atmosphere, heat-treat 50 minutes, so obtain on the active material main body, having given the active material particle of conductive auxiliary agent at 500 ℃.

(embodiment 25)

Will be as the LiFePO of the average grain diameter 3 μ m of active material main body ₄Carry out dry process 80 minute with 85: 15 mixed proportion of mass ratio by ball mill with acetylene black as the average primary particle diameter 80nm of conductive auxiliary agent; Further in Ar atmosphere, heat-treat 40 minutes, so obtain on the active material main body, having given the active material particle of conductive auxiliary agent at 500 ℃.

(comparative example 4)

Will be as the LiFePO of the average grain diameter 3 μ m of active material main body ₄Carry out dry process 55 minute with 90: 10 mixed proportion of mass ratio by ball mill with acetylene black as the average primary particle diameter 50nm of conductive auxiliary agent; Further in Ar atmosphere, heat-treat 48 minutes, so obtain on the active material main body, having given the active material particle of conductive auxiliary agent at 500 ℃.

(comparative example 5)

Will be as the LiFePO of the average grain diameter 3 μ m of active material main body ₄Carry out dry process 105 minute with 82.5: 17.5 mixed proportion of mass ratio by ball mill with acetylene black as the average primary particle diameter 80nm of conductive auxiliary agent; Further in Ar atmosphere, heat-treat 80 minutes, so obtain on the active material main body, having given the active material particle of conductive auxiliary agent at 650 ℃.

(comparative example 6)

Will be as the LiFePO of the average grain diameter 3 μ m of active material main body ₄Carry out dry process 105 minute with 80: 20 mixed proportion of mass ratio by ball mill with acetylene black as the average primary particle diameter 80nm of conductive auxiliary agent; Further in Ar atmosphere, heat-treat 80 minutes, so obtain on the active material main body, having given the active material particle of conductive auxiliary agent at 500 ℃.

< the SEM photo is observed and evaluating characteristics >

For the active material particle that obtains by embodiment 5～25 and comparative example 4～6, with carry out with embodiment 1 identical step that the SEM photo is observed, the mensuration of the constant potential charge-discharge characteristic of active material particle and use active material particle to make the characteristic of electrode evaluation that obtains.Its result is shown in table 2.

[table 2]

	Active material: conductive auxiliary agent (mass ratio)	The SEM photo is observed					The constant potential charge-discharge characteristic of active material particle		Electrode characteristic
										Coverage rate/%	Ratio/the % of pantostrat	Have or not projection	R _max/ ％	A/B	80% the charging interval/second	80% the discharge time/second	Rate characteristic (5C/1C)/%
		Embodiment 5	90∶10	55	18.3	Have	5	0.7	43									65	95
Embodiment 6	90∶10									48	33.5	Have	5	0.5	41	63	96
		Embodiment 7	90∶10	41	30.8	Have	7	0.7	46									66	95
Embodiment 8	90∶10									22	8	Have	12	6	63	94	90
		Embodiment 9	90∶10	25	10	Have	12	3	31									68	95
Embodiment 10	90∶10									37	12	Have	12	1.7	28	61	96
		Embodiment 11	90∶10	44	15	Have	12	1.3	19									53	99
Embodiment 12	90∶10									46	18	Have	12	1	15	41	100
		Embodiment 13	90∶10	52	20	Have	12	0.8	9									19	100
Embodiment 14	90∶10									63	33	Have	12	0.6	8	17	100
		Embodiment 15	90∶10	68	45	Have	12	0.5	9									20	100
Embodiment 16	90∶10									37	47	Have	12	1.5	13	46	100
		Embodiment 17	90∶10	72	50	Have	12	0.15	14									49	98
Embodiment 18	90∶10									29	53	Have	12	1.2	43	65	96
		Embodiment 19	90∶10	81	70	Have	12	0.3	47									74	95
Embodiment 20	90∶10									84	80	Have	12	0.12	53	81	93
		Embodiment 21	90∶10	89	83	Have	12	0.05	61									95	90
Embodiment 22	90∶10									41	18	Have	18	0.6	45	72	95
		Embodiment 23	90∶10	57	47.5	Have	18	0.9	43									68	96
Embodiment 24	87.5∶12.5									74	33	Have	30	0.85	32	52	100
		Embodiment 25	85∶15	67	45	Have	30	0.45	26									44	100
Comparative example 4	90∶10									42	15.5	Have	3.5	1.75	69	122	81
		Comparative example 5	82.5∶17.5	91	33	Have	33	0.14	78									131	78
Comparative example 6	80∶20									92	45	Have	33	0.11	83	145	67

Claims

1. active material particle for electrode is characterized in that:

Comprise the conductive auxiliary agent that the active material main body covers the surface of this active material main body with part and has electronic conductivity,

On the surface of said active material main body, be formed with the projection that constitutes by said conductive auxiliary agent,

Said projection from the height of said active material body surfaces be said active material main body particle diameter 5～30%, said particle diameter is the minor axis diameter of being tried to achieve by SEM.

2. active material particle for electrode as claimed in claim 1 is characterized in that:

Said conductive auxiliary agent directly covers said active material main body.

3. active material particle for electrode as claimed in claim 1 is characterized in that:

Said projection has voidage greater than the zone in the voidage of said active material main body side in its tip side.

4. active material particle for electrode as claimed in claim 1 is characterized in that:

Has the pantostrat that the said conductive auxiliary agent by the surface that covers 10～80% said active material main body constitutes.

5. active material particle for electrode as claimed in claim 1 is characterized in that:

5～60% of the surface of said active material main body is not covered by said conductive auxiliary agent but exposes, and is continuous.

6. electrode is characterized in that:

This electrode with a kind of active material particle for electrode as constituent material; This active material particle for electrode comprises the conductive auxiliary agent that the active material main body covers the surface of this active material main body with part and has electronic conductivity; On the surface of said active material main body, be formed with the projection that constitutes by said conductive auxiliary agent; Said projection from the height on the surface of said active material main body be said active material main body particle diameter 5～30%, said particle diameter is the minor axis diameter of being tried to achieve by SEM.

7. electrochemical appliance is characterized in that:

The dielectric substrate that has anode, negative electrode and ionic conductivity is arranged, and have constituting of said anode and said negative electrode Jie relative configuration by said dielectric substrate,

In said anode and the said negative electrode at least one is to contain the electrode of a kind of active material particle for electrode as constituent material; This active material particle for electrode comprises the conductive auxiliary agent that the active material main body covers the surface of this active material main body with part and has electronic conductivity; On the surface of said active material main body, be formed with the projection that constitutes by said conductive auxiliary agent; Said projection from the height on the surface of said active material main body be said active material main body particle diameter 5～30%, said particle diameter is the minor axis diameter of being tried to achieve by SEM.

8. the manufacturing approach of an electrode is characterized in that:

Has the operation that a kind of active material particle for electrode and adhesive and conductive auxiliary agent are mixed mutually; This active material particle for electrode comprises the conductive auxiliary agent that the active material main body covers the surface of this active material main body with part and has electronic conductivity; On the surface of said active material main body, be formed with the projection that constitutes by said conductive auxiliary agent; Said projection from the height on the surface of said active material main body be said active material main body particle diameter 5～30%, said particle diameter is the minor axis diameter of being tried to achieve by SEM.