CN102339999B - Polyanion composite material, its preparation method and application - Google Patents
Polyanion composite material, its preparation method and application Download PDFInfo
- Publication number
- CN102339999B CN102339999B CN201010230783.4A CN201010230783A CN102339999B CN 102339999 B CN102339999 B CN 102339999B CN 201010230783 A CN201010230783 A CN 201010230783A CN 102339999 B CN102339999 B CN 102339999B
- Authority
- CN
- China
- Prior art keywords
- composite material
- boron
- weight percentage
- nitrogen
- carbon
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/10—Energy storage using batteries
Abstract
The invention relates to a polyanion composite material, which has a general formula of BxCyNz-LiaD' bMcD'' dXOeAf, with BxCyNz as a compound of boron and carbon, or carbon and nitrogen, or boron, carbon and nitrogen. The invention provides a preparation method of the composite material and its application. The invention also provides a positive electrode with the composite material of the invention and a lithium battery containing the positive electrode. The composite material provided in the invention has high electronic conductivity and ionic conductivity, especially has an excellent rate performance and good cycle stability.
Description
Technical field
The present invention relates to a kind of polyanion composite material and its production and use, particularly, the present invention relates to a kind of polyanion composite material that contains boron carbon or carbon nitrogen or boron carbonitride and its production and use.
Background technology
Lithium ion battery has been widely used in various portable sets at present, and small lot has been used for electric motor car and energy-storage battery group etc., these application are also simultaneously more and more higher to the requirement of the properties of lithium ion battery, such as high-energy-density, high power density, high rate performance, cyclical stability, fail safe etc.The positive electrode of using in commercial batteries is at present mainly LiCoO
2, LiMn
2o
4deng, negative pole is mainly graphite-like material with carbon element.The LiFePO with olivine-type (Olivine) that the people such as Goodenough in 1997 find
4as the representative of phosphate cathode material, the plurality of advantages such as this material has that low price, specific capacity are high, long service life, environmental friendliness and thermal stability height.For example, LiFePO
4one of component Fe environment is caused to any harm hardly, with its safe voltage range, good cycle performance, caused people's interest.LiMPO
4belong to rhombic system, lithium ion is from LiFePO
4in while deviating from completely, volume-diminished 6.81%.Compare LiFePO with other anode material for lithium-ion batteries
4itself be insulator, its intrinsic conductivity is low by (10
-12-10
-9s cm
-1), Li
+at LiFePO
4in chemical diffusion coefficient also lower, constant current intermittently the value of titration technique (GITT) and ac impedance technology (AC) mensuration 1.8 * 10
-16-2.2 * 10
-14cm
2s
-1, when high current charge-discharge, the capacity of battery will be far below its theoretical capacity.
In order to solve lower electronic conductivity and ionic diffusion coefficient problem, mainly contain at present three kinds of methods: first method is to reduce the particle scale of material or form a kind of porous material; Second method is heteroatom doping, as Na
+, Mg
2+the doping of ion etc.; Or formation oxygen room (referring to Chinese patent ZL 200410037502.8 and ZL 200410101618.3); The third method is carbon to be carried out in material granule surface be coated.At present, carbon coating technology is widely used in the modification of lithium ion battery positive and negative electrode material, only contains carbon in coating layer.Be typically the most LiFePO
4, the people such as Armand M. disclose LiFePO
4the method of coated with carbon (with reference to Ravet N, Chouinard Y, Magnan JF, Besner S, Gauthier M, Armand M, JOURNAL OF POWER SOURCES, 97-8:503-507,2001, and Chinese patent application 200810149531.1), the electronics contact between particle improved, improve the electronic conductivity of material, greatly improved LiFePO
4chemical property, become the necessary condition of its commercial applications.
Although these improve the multiplying power property of really having improved material, but in the practical application of battery, particularly in the application of high-power and long-life batteries, for example surpass 10C discharge and recharge (being equivalent to 6 minutes batteries entirely fills entirely and put) time, require the high rate performance of material very high, capability retention must be more than 80%, require to circulate in more than several thousand times simultaneously, this just requires electrode material to have higher electronic conductance and ionic conductance simultaneously, and good electrically contacting between maintenance particle, also to there is high interface stability, and adopt the above-mentioned material obtaining of improving one's methods can not meet above requirement.
Summary of the invention
The object of the invention is in order to overcome existing LiFePO
4electronics and ionic conductivity Deng polyanion class material during as positive pole material of secondary lithium battery are low, adopt current existing technical method can not improve the shortcoming of high rate performance and the cycle performance of material simultaneously, thereby a kind of polyanion composite material is provided, and the high conductive compound that this composite material contains boron carbon or carbon nitrogen or boron carbon nitrogen by introducing forms B
xc
yn
z-Li
ad '
bm
cd "
dxO
ea
fcomposite material significantly improves high rate performance and the cycle performance of material.Positive pole and lithium battery that the present invention also provides preparation method and the purposes of above-mentioned composite material and adopts above-mentioned composite material to prepare.
Technical scheme of the present invention is as follows:
A composite material, this composite material has following general formula: B
xc
yn
z-L
ad '
bm
cd "
dxO
ea
f,
Wherein, B
xc
yn
zfor containing boron carbon or carbon nitrogen or boron carbon nitrogen compound;
L is selected from a kind of in Li and Na, and preferably L is Li;
D ' is selected from a kind of in Na, Mg, Al, Si, K, Ca, V, Cr, Fe, Co, Ni, Cu, Zn, Ga, Ge, Y, Zr, Nb, Ag, In, Sn, La, Ce, Ta and W;
M is selected from a kind of in Fe, Mn, Co, Ni, Ti and V;
D " is selected from a kind of in Li, Na, M g, Al, Si, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge, Y, Zr, Nb, Mo, Ag, In, Sn, Ta, W, La and Ce;
X is selected from a kind of in P, Si, S, B and C;
A is selected from a kind of in N and F;
And D ', M and D " are a kind of element when different;
X, y, z, a, b, c, d, e, f represents molar percentage, 0≤x < 1,0 < y < 1,0≤z < 1,0 < a≤2,0≤b <, 1,0 < c≤1,0≤d < 1,3≤e≤4,0≤f≤1, and x is 0 when different with z.
In above-mentioned composite material, described B
xc
yn
zbe coated on Li
ad '
bm
cd "
dxO
ea
fthe surface of material granule.
In above-mentioned composite material, described B
xc
yn
zweight percentage in described composite material is 0.1%-20%, is preferably 1%-10%.
In above-mentioned composite material, when x=0, described B
xc
yn
zthe weight percentage of middle nitrogen is 0.001%-50%, is preferably 0.01%-30%; The weight percentage of nitrogen in described composite material is 0.0001%-10%, is preferably 0.01%-3%; When x ≠ 0, described B
xc
yn
zthe weight percentage of middle nitrogen is 0%-50%, is preferably 0.01%-30%; The weight percentage of nitrogen in described composite material is 0%-10%, is preferably 0.01%-3%.
In above-mentioned composite material, when z=0, described B
xc
yn
zthe weight percentage of middle boron is 0.001%-30%, is preferably 0.01%-10%; The weight percentage of boron in described composite material is 0.0001%-6%, is preferably 0.01%-1%; When z ≠ 0, described B
xc
yn
zthe weight percentage of middle boron is 0%-30%, is preferably 0.01%-10%; The weight percentage of boron in described composite material is 0%-10%, is preferably 0.01%-1%.
The present invention also provides the preparation method of above-mentioned composite material, and this preparation method is selected from coated method or mechanical ball-milling method.
Wherein, described coated method comprises the steps:
(1) by L
ad '
bm
cd "
dxO
ea
fwith the ionic liquid that contains boron carbon or carbon nitrogen or boron carbon nitrogen, for example [EMIm] [N (CN)
2] (1-ethyl-3-methylimidazolium dicyanamide) or other organic compound mix 5-30 minute in blender, obtains the mixture of the two
Wherein, B
xc
yn
zfor containing boron carbon or carbon nitrogen or boron carbon nitrogen compound;
L is selected from a kind of in Li and Na, and preferably L is Li;
D ' is selected from a kind of in Na, Mg, Al, Si, K, Ca, V, Cr, Fe, Co, Ni, Cu, Zn, Ga, Ge, Y, Zr, Nb, Ag, In, Sn, La, Ce, Ta and W;
M is selected from a kind of in Fe, Mn, Co, Ni, Ti and V;
D " is selected from a kind of in Li, Na, M g, Al, Si, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge, Y, Zr, Nb, Mo, Ag, In, Sn, Ta, W, La and Ce;
X is selected from a kind of in P, Si, S, B and C;
A is selected from a kind of in N and F;
And D ', M and D " are a kind of element when different;
X, y, z, a, b, c, d, e, f represents molar percentage, 0≤x < 1,0 < y < 1,0≤z < 1,0 < a≤2,0≤b <, 1,0 < c≤1,0≤d < 1,3≤e≤4,0≤f≤1, and x is 0 when different with z; And
(2) at tube furnace, in nitrogen or argon gas atmosphere, mixture step (1) being obtained with the speed of 2 ℃/min is warming up to 600 ℃ from room temperature, and at this temperature, keeps 2 hours, makes the abundant cracking of ionic liquid, obtains described composite material after cooling.
The present invention also provides above-mentioned composite material preparing electrode material of lithium battery, for example the purposes in positive electrode.
The present invention also provides a kind of positive pole, and this positive pole comprises collector and load on the positive electrode on this collector, and described positive electrode contains above-mentioned composite material.
The present invention also provides a kind of lithium battery, and this battery comprises positive pole, negative pole and electrolyte, the described just very above-mentioned positive pole that contains composite material of the present invention.
It is below detailed description of the present invention.
The invention provides a kind of polyanion composite material, its general formula is: B
xc
yn
z-Li
ad '
bm
cd "
dxO
ea
f,
Wherein, B
xc
yn
zfor containing boron carbon or carbon nitrogen or boron carbon nitrogen compound;
L is selected from a kind of in Li and Na, and preferably L is Li;
D ' is Na, Mg, Al, Si, K, Ca, V, Cr, Fe, Co, Ni, Cu, Zn, Ga, Ge, Y, Zr, Nb, Ag, In, Sn, La, Ce, Ta, W;
M is Fe, Mn, Co, Ni, Ti, V;
D " be Li, Na, Mg, Al, Si, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge, Y, Zr, Nb, Mo, Ag, In, Sn, Ta, W, La, Ce;
X is P, Si, S, B, C;
A is N, F;
And M and M " are a kind of element when different;
X, y, z, a, b, c, d, e, f represents molar percentage, 0≤x < 1,0 < y < 1,0≤z < 1,0 < a≤2,0≤b <, 1,0 < c≤1,0≤d < 1,3≤e≤4,0≤f≤1, and x is 0 when different with z.
According to the present invention, B
xc
yn
zfor containing boron carbon or carbon nitrogen or boron carbon nitrogen compound, Li
ad '
bm
cd "
dxO
ea
ffor active electrode material, be preferably LiFePO
4.The high conductive compound that the present invention contains boron carbon or carbon nitrogen or boron carbon nitrogen by interpolation, can improve the electronic conductivity of composite material on the one hand, can reduce on the other hand lithium ion at its active material and the migration activation energy that contains boron carbon or carbon nitrogen or boron carbonitride interface, thereby improve lithium ion in the ionic conductivity of interface, improved the high rate performance of composite material.The best effect of composite material of the present invention is to contain boron carbon or carbon nitrogen or boron carbon nitrogen compound is coated on LiFePO
4on the surface of polyanion class material granule, improved like this interface stability, and then improved the cycle life of composite material.
In the present invention, described in, contain boron carbon or carbon nitrogen or boron carbon nitrogen compound B
xc
yn
zcan be coated on active electrode material Li
ad '
bm
cd "
dxO
ea
fsurface, this can improve interface stability, and then improves the cycle life of composite material.
In the present invention, described B
xc
yn
zweight percentage in described composite material is 0.1%-20%, is preferably 1%-10%.
In the present invention, when x=0, described B
xc
yn
zthe weight percentage of middle nitrogen is 0.001%-50%, is preferably 0.01%-30%; The weight percentage of nitrogen in described composite material is 0.0001%-10%, is preferably 0.01%-3%; When x ≠ 0, described B
xc
yn
zthe weight percentage of middle nitrogen is 0%-50%, is preferably 0.01%-30%; The weight percentage of nitrogen in described composite material is 0%-10%, is preferably 0.01%-3%.
In the present invention, when z=0, described B
xc
yn
zthe weight percentage of middle boron is 0.001%-30%, is preferably 0.01%-10%; The weight percentage of boron in described composite material is 0.0001%-6%, is preferably 0.01%-1%; When z ≠ 0, described B
xc
yn
zthe weight percentage of middle boron is 0%-30%, is preferably 0.01%-10%; The weight percentage of boron in described composite material is 0%-10%, is preferably 0.01%-1%.
It is conductivity, high rate performance and the cycle life in order to improve composite material that the present invention selects specific proportioning and composition.
The present invention also provides the preparation method of above-mentioned composite material, and this preparation method can comprise the steps:
(1) by L
ad '
bm
cd "
dxO
ea
fwith the ionic liquid that contains boron carbon or carbon nitrogen or boron carbon nitrogen, for example [EMIm] [N (CN)
2] or other organic compound in blender, mix 5-30 minute, obtain the mixture of the two
Wherein, B
xc
yn
zfor containing boron carbon or carbon nitrogen or boron carbon nitrogen compound;
L is selected from a kind of in Li and Na, and preferably L is Li;
D ' is selected from a kind of in Na, Mg, Al, Si, K, Ca, V, Cr, Fe, Co, Ni, Cu, Zn, Ga, Ge, Y, Zr, Nb, Ag, In, Sn, La, Ce, Ta and W;
M is selected from a kind of in Fe, Mn, Co, Ni, Ti and V;
D " is selected from a kind of in Li, Na, Mg, Al, Si, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge, Y, Zr, Nb, Mo, Ag, In, Sn, Ta, W, La and Ce;
X is selected from a kind of in P, Si, S, B and C;
A is selected from a kind of in N and F;
And D ', M and D " are a kind of element when different;
X, y, z, a, b, c, d, e, f represents molar percentage, 0≤x < 1,0 < y < 1,0≤z < 1,0 < a≤2,0≤b <, 1,0 < c≤1,0≤d < 1,3≤e≤4,0≤f≤1, and x is 0 when different with z; And
(2) at tube furnace, in nitrogen or argon gas atmosphere, mixture step (1) being obtained with the speed of 2 ℃/min is warming up to 600 ℃ from room temperature, and at this temperature, keeps 2 hours, makes the abundant cracking of ionic liquid, obtains described composite material after cooling.
In one embodiment of the invention, it is specific as follows that the present invention prepares the method for composite material:
(1) take appropriate active electrode material powder, for example be put in centrifuge tube, in required ratio, get the ionic liquid or other organic compound that contain boron carbon or carbon nitrogen or boron carbon nitrogen, adding powder to be placed in shaker mixer vibrates 5 to 30 minutes, ionic liquid is fully mixed with active electrode material, depending on the difference of ionic liquid additional proportion, obtain mixture for the dry wet different powder/grains of sand shape/gunk of degree; And
(2) at tube furnace, in argon gas or nitrogen atmosphere, from room temperature, with the speed of 2 ℃/min, be warming up to 600 ℃/min, at 600 ℃/min, keep 2 hours, make the abundant cracking of ionic liquid, after tube furnace cooling, take out sample, after grinding, put into drier standby.Sample after sintering is depending on adding the difference of ionic liquid ratio, and color is grey black to black.
Preparation method described above is coated method, and as in common knowledge in this area, those of ordinary skills also can adopt other preparation method, such as mechanical ball-milling method etc., prepares above-mentioned composite material of the present invention.
The present invention also provides above-mentioned composite material preparing electrode material of lithium battery, for example the purposes in positive electrode.
The present invention also provides a kind of positive pole, and this positive pole comprises collector and load on the positive electrode on this collector, and described positive electrode contains above-mentioned composite material.Because the present invention only relates to the improvement to composite material, anodal preparation method and anodal composition are not particularly limited, adopt the preparation method of this area routine and form.Described collector can adopt all available plus plate current-collecting bodies known in the art, and to it, there is no particular limitation in the present invention.
The present invention also provides a kind of lithium battery, and this battery comprises positive pole, negative pole and electrolyte, the described just very above-mentioned positive pole that contains composite material of the present invention.
Particularly, the present invention can be used for above-mentioned composite material the positive electrode of serondary lithium battery, makes the positive pole of serondary lithium battery, forms serondary lithium battery with conventional negative pole, electrolyte.Carbon, conducting metal oxide or metal that the conductive additive using in positive pole is used for routine; The active material that negative pole is used comprises can embedding lithium material with carbon element, lithium metal, lithium alloy, spinel lithium titanate or sulfide; Between positive pole and negative pole, be full of electrolyte, positive pole is burn-on respectively to go between with one end of negative pole and is connected with the battery case two ends of mutually insulated.
Adopting polyanion composite material of the present invention to be applicable to various mobile electronic devices as the above-mentioned serondary lithium battery of positive pole maybe needs the equipment of mobile driven by energy and the deposit of non-moving type or back-up source, and is not limited to this.
Compared with prior art, the present invention at least has following beneficial effect:
1, the present invention is at LiFePO
4the high conductive compound that contains boron carbon or carbon nitrogen or boron carbon nitrogen Deng introducing in polyanion class material, can improve the electronic conductivity of composite material on the one hand, can reduce on the other hand lithium ion at its active material and the migration activation energy that contains boron carbon or carbon nitrogen or boron carbonitride interface, thereby improve lithium ion in the ionic conductivity of interface, improved the high rate performance of composite material.
2, the present invention is coated on for example LiFePO by the high conductive compound that contains boron carbon or carbon nitrogen or boron carbon nitrogen
4on the surface of polyanion class material material particle, improved interface stability, and then improved the cycle life of positive electrode.
3, method for coating step of the present invention is simple, has overcome tradition and has usingd sucrose solution or polymer solution during as the presoma of carbon, and the problem of the phase-splitting that solvent evaporation brings in heat treatment process/gather, causes the inhomogeneous of carbon coating layer.Especially to porous material, covered effect is better.Implementation method of the present invention is simple, and the content of boron carbon nitrogen is easily controlled, and is with a wide range of applications.
4. compare with only using the composite material of carbon containing, use the conductivity of composite material of the high conductive compound that contains boron carbon or carbon nitrogen or boron carbon nitrogen of the present invention good, the lithium battery high rate performance of preparation and long cyclical stability are all greatly improved.
Embodiment
Below in conjunction with specific embodiment, further set forth the present invention.But these embodiment only limit to explanation
The present invention and being not used in limits the scope of the invention.The experimental technique of unreceipted specific experiment condition in the following example, conventionally according to normal condition, or the condition of advising according to manufacturer.
embodiment 1
Under dry atmosphere, by the ionic liquid that contains carbon nitrogen [EMIm] [N (CN)
2] 0.3g adds 1gLiFePO
4powder vibrates 30 minutes in shaker mixer, obtains husky particulate mixtures.This mixture is transferred to alumina crucible, put into tube furnace, logical argon gas or nitrogen.From room temperature, with the speed of 2 ℃/min, being warming up to 600 ℃, at 600 ℃, keeping 2 hours, make the abundant cracking of ionic liquid, after tube furnace cooling, take out sample, is black powder after grinding, and is composite material of the present invention.Wherein, the weight percentage of nitrogen in carboritride is 28% left and right, and the weight percentage of carboritride in composite material is 5% left and right.
By sample making simulated battery.By the LiFePO before and after coated
4: acetylene black: PVdF binding agent=85%: the ratio of 10%: 5% is mixed to form slurry at normal temperatures and pressures, be evenly coated on the substrate that aluminium foil is collector and make electrode slice, the film thickness of gained is 5-30 micron, as the positive pole of simulated battery.The negative pole of simulated battery is used metal lithium sheet, the LiPF that electrolyte is 1M
6be dissolved in (volume ratio 1: 1) in the EC of 1L and the mixed solvent of DEC.Positive pole, negative pole, electrolyte are assembled into simulated battery in the glove box of argon shield.The testing procedure of simulated battery: first the electric current with C/2 discharges and recharges between 2-4.2V, the capacity of emitting is the discharge capacity under this multiplying power; Circulate after several weeks, progressively improve the current density discharging and recharging, until 10C.The test result of simulated battery is listed in table 1.
embodiment 2-3
Press the method preparation of embodiment 1 and press the polyanion composite material for serondary lithium battery of the present invention that table 1 forms, difference is, the content of ionic liquid and active material is different, obtains the composite material of different carboritride weight percentages, is respectively 2% and 12% left and right.
The assembling of the positive pole of simulated battery, negative pole, electrolyte and battery is same as embodiment 1, and its test result is listed in table 1.
embodiment 4-5
Press the method preparation of embodiment 1 and press the polyanion composite material for serondary lithium battery of the present invention that table 1 forms, difference is, heat treatment temperature is different, obtains the composite material of the weight percentage of different nitrogen in carboritride, is respectively 38% and 7% left and right.
The assembling of the positive pole of simulated battery, negative pole, electrolyte and battery is same as embodiment 1, and its test result is listed in table 1.
embodiment 6
The LiFePO that contains carboritride
4composite material can also synthesize by following steps.First, according to mol ratio, take Li at 0.5: 1: 1
2cO
3, FeC
2o
42H
2o and NH
4h
2pO
4, after mechanical ball milling, by this mixture again with a certain amount of ionic liquid [EMIm] [N (CN)
2] mix that (mixed proportion is 1 gram of LiFePO
4: 0.3 gram-ion liquid), at high-purity Ar gas or N
2under the protective atmosphere of gas, heat-treat, heat treatment temperature is 650 ℃, this temperature constant temperature 4 hours, then naturally cools to room temperature, obtains the LiFePO that contains carboritride
4composite material is black powder after grinding.
The assembling of the positive pole of simulated battery, negative pole, electrolyte and battery is same as embodiment 1, and its test result is listed in table 1.
embodiment 7-21
Press the method preparation of embodiment 1 and press the polyanion composite material for serondary lithium battery of the present invention that table 1 forms, difference is that selected polyanion positive electrode is different, has obtained the different polyanion composite materials that contain carboritride.
The assembling of the positive pole of simulated battery, negative pole, electrolyte and battery is same as embodiment 1, and its test voltage scope is adjusted to some extent according to different positive electrodes, and its test result is listed in table 1.
embodiment 22
Press the method preparation of embodiment 1 and press the polyanion composite material for serondary lithium battery of the present invention that table 1 forms, difference is, selected boron carbon source is that the perfluor that is dissolved in propylene carbonate replaces triphenyl borine, has obtained the LiFePO that contains borocarbide
4anode composite material.
By SEM, the pattern of relatively more coated front and back, finds the not variation of coated rear pattern; The result of XRD and TEM is known, and the crystal structure of sample does not change, and is olivine structural; From the result of Raman and XPS, can find out, surface has the existence of boron, carbon really, and the weight percentage of boron in borocarbide is 4% left and right.TG result shows, the weight percentage of borocarbide in composite material is 7% left and right.
The assembling of the positive pole of simulated battery, negative pole, electrolyte and battery is same as embodiment 1, and its test result is listed in table 1.
embodiment 23
The LiFePO that contains borocarbide
4composite material can also synthesize by following steps.First, according to mol ratio, take Li at 0.5: 1: 1
2cO
3, FeC
2o
42H
2o and NH
4h
2pO
4, after mechanical ball milling, this mixture is replaced to triphenyl borine with a certain amount of perfluor that is dissolved in propylene carbonate again and mixes that (mixed proportion is 1 gram of LiFePO
4: 0.35 gram of presoma that contains boron carbon), at high-purity Ar gas or N
2under the protective atmosphere of gas, heat-treat, heat treatment temperature is 650 ℃, this temperature constant temperature 4 hours, then naturally cools to room temperature, obtains the LiFePO that contains carboritride
4composite material is black powder after grinding.
The assembling of the positive pole of simulated battery, negative pole, electrolyte and battery is same as embodiment 1, and its test result is listed in table 1.
embodiment 24-34
Press the method preparation of embodiment 1 and 22 and press the polyanion composite material for serondary lithium battery of the present invention that table 1 forms, difference is that selected polyanion positive electrode is different, has obtained the different polyanion composite materials that contain carboritride.
The assembling of the positive pole of simulated battery, negative pole, electrolyte and battery is same as embodiment 1, and its test voltage scope is adjusted to some extent according to different positive electrodes, and its test result is listed in table 1.
embodiment 35
Press the method preparation of embodiment 1 and press the polyanion composite material for serondary lithium battery of the present invention that table 1 forms, difference is that selected boron carbon nitrogen source is ionic liquid [BCNIm] [BF
4] (1,3-bis (cyanomethyl) imidazolium fluoroborate), obtained the LiFePO that contains boron carbonitride
4anode composite material.
By SEM, the pattern of relatively more coated front and back, finds the not variation of coated rear pattern; The result of XRD and TEM is known, and the crystal structure of sample does not change, and is olivine structural; From the result of Raman and XPS, can find out, surface has the existence of boron, carbon, nitrogen really, and the weight percentage of boron in boron carbonitride is 2% left and right, and the weight percentage of nitrogen in boron carbonitride is 25% left and right.TG result shows, the weight percentage of boron carbonitride in composite material is 5% left and right.
The assembling of the positive pole of simulated battery, negative pole, electrolyte and battery is same as embodiment 1, and its test result is listed in table 1.
embodiment 36
The LiFePO that contains boron carbonitride
4composite material can also synthesize by following steps.First, according to mol ratio, take Li at 0.5: 1: 1
2cO
3, FeC
2o
42H
2o and NH
4h
2pO
4, after mechanical ball milling, by this mixture again with a certain amount of ionic liquid [BCNIm] [BF
4] mix that (mixed proportion is 1 gram of LiFePO
4: 0.26 gram-ion liquid [BCNIm] [BF
4]), at high-purity Ar gas or N
2under the protective atmosphere of gas, heat-treat, heat treatment temperature is 650 ℃, this temperature constant temperature 4 hours, then naturally cools to room temperature, obtains the LiFePO that contains boron carbonitride
4composite material is black powder after grinding.
The assembling of the positive pole of simulated battery, negative pole, electrolyte and battery is same as embodiment 1, and its test result is listed in table 1.
embodiment 37-55
Press the method preparation of embodiment 1 and 35 and press the polyanion composite material for serondary lithium battery of the present invention that table 1 forms, difference is, selected polyanion positive electrode is different, has obtained the different polyanion composite materials that contain boron carbonitride.
The assembling of the positive pole of simulated battery, negative pole, electrolyte and battery is same as embodiment 1, and its test voltage scope is adjusted to some extent according to different positive electrodes, and its test result is listed in table 1.
comparative example 1liFePO before and after embodiment 1 is coated
4performance comparison research
By SEM, LiFePO before and after comparing embodiment 1 is coated
4pattern, find coated after pattern do not change; The result of XRD and TEM is known, and the crystal structure of sample does not change, and is olivine structural; From the result of Raman and XPS, can find out, surface has the existence of nitrogen, carbon really, and the weight percentage of nitrogen in carboritride is 28% left and right.TG result shows, the weight percentage of carboritride in composite material is 5% left and right.
For the chemical property of the coated front and back of comparative study sample, by sample making simulated battery.By the LiFePO before and after coated
4: acetylene black: PVdF binding agent=85%: the ratio of 10%: 5% is mixed to form slurry at normal temperatures and pressures, be evenly coated on the substrate that aluminium foil is collector and make electrode slice, the film thickness of gained is 5-30 micron, as the positive pole of simulated battery.The negative pole of simulated battery is used metal lithium sheet, the LiPF that electrolyte is 1M
6be dissolved in (volume ratio 1: 1) in the EC of 1L and the mixed solvent of DEC.Positive pole, negative pole, electrolyte are assembled into simulated battery in the glove box of argon shield.The testing procedure of simulated battery: first the electric current with C/2 discharges and recharges between 2-4.2V, the capacity of emitting is the discharge capacity under this multiplying power; Circulate after several weeks, progressively improve the current density discharging and recharging, until 10C.The test result of simulated battery is listed in table 1.
According to the result of table 1, can find out, sample after carboritride is coated has shown higher lithium storage content, high rate performance and cycle performance, under the high magnification of 5C and 10C, specific capacity is respectively 147mAh/g and 132mAh/g (capability retention is respectively 92% and 83%), and is only 81mAh/g and 63mAh/g before coated.The battery of the sample assembly after carboritride is coated is grown circulation under 1C multiplying power, and after circulation 800 weeks, the conservation rate of specific capacity is 91%.As can be seen here, the coated LiFePO that greatly improved of carboritride
4conductivity, its high rate performance and long cyclical stability are all greatly improved.
comparative example 2the only contrast of the sample of carbon containing and the chemical property of composite material of the present invention
For comparative study, we have selected sucrose is simultaneously carbon source, and under the cracking condition identical with embodiment 1, the content of controlling sucrose makes only to contain in pyrolysis product carbon, and the percentage by weight of carbon in composite material is 5% left and right.
By sample making simulated battery.By the LiFePO before and after coated
4: acetylene black: PVdF binding agent=85%: the ratio of 10%: 5% is mixed to form slurry at normal temperatures and pressures, be evenly coated on the substrate that aluminium foil is collector and make electrode slice, the film thickness of gained is 5-30 micron, as the positive pole of simulated battery.The negative pole of simulated battery is used metal lithium sheet, the LiPF that electrolyte is 1M
6be dissolved in (volume ratio 1: 1) in the EC of 1L and the mixed solvent of DEC.Positive pole, negative pole, electrolyte are assembled into simulated battery in the glove box of argon shield.The testing procedure of simulated battery: first the electric current with C/2 discharges and recharges between 2-4.2V, the capacity of emitting is the discharge capacity under this multiplying power; Circulate after several weeks, progressively improve the current density discharging and recharging, until 10C.The test result of simulated battery is listed in table 1.
According to the result of table 1, can find out, composite material (for example embodiment 35) containing boron carbonitride coated of the present invention is under the high magnification of 5C and 10C, battery performance is greatly improved, specific capacity can be 149mAh/g and 135mAh/g (capability retention is respectively 93% and 84%) respectively, the coated material of other carbon nitrogen or boron carbon is under the high magnification of 5C and 10C, battery performance be also greatly improved (referring to table 1), and only having the coated sample of carbon, its specific capacity is respectively 132mAh/g and 121mAh/g.As embodiment 35, the battery of the sample assembly after boron carbonitride is coated is grown circulation under 1C multiplying power, and after circulation 800 weeks, the conservation rate of specific capacity is 92%.As can be seen here, the coated LiFePO that greatly improved of boron carbonitride
4conductivity, its high rate performance and long cyclical stability are all greatly improved.The performance of clad material that the cladding ratio that contains carboritride or borocarbide or boron carbonitride only contains carbon is more excellent.
The composition of table 1 composite material and the test result of simulated battery
Claims (20)
1. a polyanion composite material, this composite material has following general formula: B
xc
yn
z-L
ad '
bm
cd 〞
dxO
ea
f,
Wherein, B
xc
yn
zfor containing boron carbon or boron carbon nitrogen compound;
L is selected from a kind of in Li and Na;
D ' is selected from a kind of in Na, Mg, Al, Si, K, Ca, V, Cr, Fe, Co, Ni, Cu, Zn, Ga, Ge, Y, Zr, Nb, Ag, In, Sn, La, Ce, Ta and W;
M is selected from a kind of in Fe, Mn, Co, Ni, Ti and V;
D 〞 is selected from a kind of in Li, Na, Mg, Al, Si, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge, Y, Zr, Nb, Mo, Ag, In, Sn, Ta, W, La and Ce;
X is selected from a kind of in P, Si, S, B and C;
A is selected from a kind of in N and F;
And when D ', M are different from D 〞, be a kind of element;
X, y, z, a, b, c, d, e, f represents molar percentage, 0 ﹤ x ﹤ 1,0 ﹤ y ﹤ 1,0≤z ﹤ 1,0 ﹤ a≤2,0≤b ﹤, 1,0 ﹤ c≤1,0≤d ﹤, 1,3≤e≤4,0≤f≤1.
2. composite material according to claim 1, is characterized in that, L is Li.
3. composite material according to claim 1, is characterized in that, described B
xc
yn
zbe coated on Li
ad '
bm
cd 〞
dxO
ea
fthe surface of material granule.
4. according to the composite material described in any one in claims 1 to 3, it is characterized in that described B
xc
yn
zweight percentage in described composite material is 0.1%-20%.
5. according to the composite material described in any one in claims 1 to 3, it is characterized in that described B
xc
yn
zweight percentage 1%-10% in described composite material.
6. according to the composite material described in any one in claims 1 to 3, it is characterized in that described B
xc
yn
zthe weight percentage of middle nitrogen is 0%-50%, and the weight percentage of nitrogen in described composite material is 0%-10%.
7. according to the composite material described in any one in claims 1 to 3, it is characterized in that described B
xc
yn
zthe weight percentage of middle nitrogen is 0.01%-30%.
8. according to the composite material described in any one in claims 1 to 3, it is characterized in that, the weight percentage of nitrogen in described composite material is 0.01%-3%.
9. according to the composite material described in any one in claims 1 to 3, it is characterized in that, when z=0, described B
xc
yn
zthe weight percentage of middle boron is 0.001%-30%, and the weight percentage of boron in described composite material is 0.0001%-6%; When z ≠ 0, described B
xc
yn
zthe weight percentage of middle boron is 0%-30%, and the weight percentage of boron in described composite material is 0%-10%.
10. according to the composite material described in any one in claims 1 to 3, it is characterized in that, when z=0, described B
xc
yn
zthe weight percentage of middle boron is 0.01%-10%.
11. according to the composite material described in any one in claims 1 to 3, it is characterized in that, when z=0, the weight percentage of boron in described composite material is 0.01%-1%.
12. according to the composite material described in any one in claims 1 to 3, it is characterized in that, and when z ≠ 0, described B
xc
yn
zthe weight percentage of middle boron is 0.01%-10%.
13. according to the composite material described in any one in claims 1 to 3, it is characterized in that, when z ≠ 0, the weight percentage of boron in described composite material is 0.01%-1%.
The preparation method of the composite material in 14. claims 1 to 13 described in any one, this preparation method is selected from coated method or mechanical ball-milling method.
15. preparation methods according to claim 14, is characterized in that, described coated method comprises the steps:
(1) by L
ad '
bm
cd 〞
dxO
ea
fin blender, mix 5-30 minute with the ionic liquid or other organic compound that contain boron carbon or boron carbon nitrogen, obtain the mixture of the two
Wherein, B
xc
yn
zfor containing boron carbon or boron carbon nitrogen compound;
L is selected from a kind of in Li and Na;
D ' is selected from a kind of in Na, Mg, Al, Si, K, Ca, V, Cr, Fe, Co, Ni, Cu, Zn, Ga, Ge, Y, Zr, Nb, Ag, In, Sn, La, Ce, Ta and W;
M is selected from a kind of in Fe, Mn, Co, Ni, Ti and V;
D 〞 is selected from a kind of in Li, Na, Mg, Al, Si, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge, Y, Zr, Nb, Mo, Ag, In, Sn, Ta, W, La and Ce;
X is selected from a kind of in P, Si, S, B and C;
A is selected from a kind of in N and F;
And when D ', M are different from D 〞, be a kind of element;
X, y, z, a, b, c, d, e, f represents molar percentage, 0 ﹤ x ﹤ 1,0 ﹤ y ﹤ 1,0≤z ﹤ 1,0 ﹤ a≤2,0≤b ﹤, 1,0 ﹤ c≤1,0≤d ﹤, 1,3≤e≤4,0≤f≤1; And
(2) at tube furnace, in nitrogen or argon gas atmosphere, mixture step (1) being obtained with the speed of 2 ℃/min is warming up to 600 ℃ from room temperature, and at this temperature, keeps 2 hours, makes the abundant cracking of ionic liquid, obtains described composite material after cooling.
16. preparation methods according to claim 15, is characterized in that, L is Li.
The purposes of composite material in 17. claims 1 to 13 described in any one in preparing electrode material of lithium battery.
18. purposes according to claim 17, is characterized in that, described electrode material is positive electrode.
19. 1 kinds of positive poles, this positive pole comprises and it is characterized in that collector and load on the positive electrode on this collector, described positive electrode contains the composite material described in any one in claim 1 to 13.
20. 1 kinds of lithium batteries, this battery comprises positive pole, negative pole and electrolyte, it is characterized in that, described positive pole comprises the positive pole described in claim 19.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201010230783.4A CN102339999B (en) | 2010-07-14 | 2010-07-14 | Polyanion composite material, its preparation method and application |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201010230783.4A CN102339999B (en) | 2010-07-14 | 2010-07-14 | Polyanion composite material, its preparation method and application |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN102339999A CN102339999A (en) | 2012-02-01 |
| CN102339999B true CN102339999B (en) | 2014-02-05 |
Family
ID=45515593
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201010230783.4A Active CN102339999B (en) | 2010-07-14 | 2010-07-14 | Polyanion composite material, its preparation method and application |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN102339999B (en) |
Families Citing this family (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102709553B (en) * | 2012-05-28 | 2015-05-20 | 深圳市贝特瑞新能源材料股份有限公司 | Positive electrode material and synthetic method thereof |
| CN104347857B (en) | 2013-07-29 | 2017-07-07 | 华为技术有限公司 | Negative electrode of lithium ionic secondary battery and preparation method thereof, cathode pole piece of lithium ion secondary battery and lithium rechargeable battery |
| CN103441278A (en) * | 2013-09-12 | 2013-12-11 | 兰州理工大学 | Method for preparing carbon-coated lithium iron phosphate through microwave pyrolysis of ionic liquid |
| CN108598398B (en) * | 2018-04-09 | 2020-12-08 | 中科锂电新能源有限公司 | Boron carbide and carbon co-coated composite positive electrode material, preparation method thereof and lithium ion battery |
| CN110233284B (en) * | 2019-07-17 | 2021-12-28 | 江西省汇亿新能源有限公司 | Low-temperature high-energy-density long-cycle lithium iron phosphate battery |
| CN111599999B (en) * | 2020-05-25 | 2022-04-08 | 蜂巢能源科技股份有限公司 | Cobalt-free cathode material, preparation method thereof and lithium ion battery |
| CN113437291B (en) * | 2021-07-27 | 2022-08-05 | 西安交通大学 | Lithium vanadium fluorophosphosilicate cathode material and preparation method thereof |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1225196A (en) * | 1996-05-07 | 1999-08-04 | 东洋炭素株式会社 | Cathode material for lithium ion secondary battery, method for manufacturing the same, and lithium ion secondary battery using the same |
| CN1244047A (en) * | 1997-07-17 | 2000-02-09 | 中国科学院化学研究所 | Carbon material as negative electrode and its preparing process and usage |
| CN1526178A (en) * | 2001-05-15 | 2004-09-01 | Fdk株式会社 | Nonaqueous electrolytic secondary battery and method of producing anode material thereof |
| CN101284655A (en) * | 2008-05-16 | 2008-10-15 | 深圳市贝特瑞新能源材料股份有限公司 | Lithium ionic cell cathode material of graphite-like structure and preparing process thereof |
| CN101371384A (en) * | 2006-01-09 | 2009-02-18 | 科诺科飞利浦公司 | A process of making carbon-coated lithium metal polyanionic powders |
-
2010
- 2010-07-14 CN CN201010230783.4A patent/CN102339999B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1225196A (en) * | 1996-05-07 | 1999-08-04 | 东洋炭素株式会社 | Cathode material for lithium ion secondary battery, method for manufacturing the same, and lithium ion secondary battery using the same |
| CN1244047A (en) * | 1997-07-17 | 2000-02-09 | 中国科学院化学研究所 | Carbon material as negative electrode and its preparing process and usage |
| CN1526178A (en) * | 2001-05-15 | 2004-09-01 | Fdk株式会社 | Nonaqueous electrolytic secondary battery and method of producing anode material thereof |
| CN101371384A (en) * | 2006-01-09 | 2009-02-18 | 科诺科飞利浦公司 | A process of making carbon-coated lithium metal polyanionic powders |
| CN101284655A (en) * | 2008-05-16 | 2008-10-15 | 深圳市贝特瑞新能源材料股份有限公司 | Lithium ionic cell cathode material of graphite-like structure and preparing process thereof |
Also Published As
| Publication number | Publication date |
|---|---|
| CN102339999A (en) | 2012-02-01 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Zhang | Structure and performance of LiFePO4 cathode materials: A review | |
| CN100377392C (en) | Anode material lithium ferric phosphate containing oxygen vacancy in use for secondary battery of lithium ion, and application | |
| CN102339999B (en) | Polyanion composite material, its preparation method and application | |
| CN101997118A (en) | Lithium ferric manganese phosphate as cathode material of lithium ion battery and preparation method thereof | |
| CN102569794B (en) | Carbon-coating method for lithium iron phosphate anode material | |
| CN106159318A (en) | Novel slice type solid-state serondary lithium battery that garnet-type solid electrolyte supports and preparation method thereof | |
| CN103000884A (en) | Vanadium sodium phosphate composite material as well as preparation method and application thereof | |
| CN1754275A (en) | High energy and power density electrochemical cells | |
| WO2017104405A1 (en) | Material for electrodes, electrode sheet for all-solid-state secondary batteries, all-solid-state secondary battery, method for producing electrode sheet for all-solid-state secondary batteries, and method for producing all-solid-state secondary battery | |
| JP2010529593A (en) | Lithium iron phosphate positive electrode active material for lithium ion battery and preparation method thereof | |
| CN109037659A (en) | A kind of preparation method of bilayer carbon-coated LiFePO 4 for lithium ion batteries material | |
| CN113651304B (en) | Organic carbon coated lithium iron phosphate positive electrode material and preparation method thereof | |
| CN103682266A (en) | Li and Mn codoped manganese phosphate/carbon composite material and preparation method thereof | |
| CN110783546A (en) | Lithium ion battery positive electrode material and preparation method thereof, lithium ion battery positive electrode slurry and positive electrode, lithium ion battery and equipment | |
| CN102315440A (en) | Spinel composite material, preparation method and application thereof | |
| CN103299459A (en) | Method for preparing a negative electrode active material | |
| CN110970618A (en) | Preparation method of low-cost lithium iron phosphate composite material | |
| CN102148367A (en) | Method for preparing lithium-ion battery anode material of lithium iron phosphate | |
| CN102569788A (en) | Lithium ion battery anode material and preparation method thereof, and lithium ion battery | |
| CN102931404A (en) | Phosphate potential boron-doped manganese phosphate lithium / carbon composite materials and preparation method thereof | |
| CN103094580A (en) | Composite anode material and synthesis method and application thereof | |
| CN103378355A (en) | Alkali metal secondary battery as well as negative active substance, negative material and negative electrode thereof, and preparation method of negative active substance | |
| Yang et al. | The study on synthesis and modification for iron phosphate | |
| Dimesso et al. | Investigation of the LiCo1− xMgxPO4 (0⩽ x⩽ 0.1) system | |
| CN115784223B (en) | High-sulfur Jiao Ji quick-charging graphite active material, preparation thereof and application thereof in lithium ion battery |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant |