CN103515600A - Ti3SiC2 and carbon composite modified LiFePO4 lithium ion battery anode material and preparation method thereof - Google Patents
Ti3SiC2 and carbon composite modified LiFePO4 lithium ion battery anode material and preparation method thereof Download PDFInfo
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- CN103515600A CN103515600A CN201310479403.4A CN201310479403A CN103515600A CN 103515600 A CN103515600 A CN 103515600A CN 201310479403 A CN201310479403 A CN 201310479403A CN 103515600 A CN103515600 A CN 103515600A
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- H01M4/58—Selection of substances as active materials, active masses, active liquids of inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy; of polyanionic structures, e.g. phosphates, silicates or borates
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Abstract
The invention discloses a Ti3SiC2 and carbon composite modified LiFePO4 lithium ion battery anode material and a preparation method thereof. Carbon-coated LiFePO4 powder is used as a substrate; lamellar Ti3SiC2 is added to the substrate to prepare Ti3SiC2 and carbon composite modified LiFePO4; the carbon-coated LiFePO4 powder comprises 1 to 10 mass percent of carbon; Ti3SiC2 accounts for 0.5 to 10 mass percent of the composite modified powder. Nano-particle Ti3SiC2 which is of a one-dimensional linear or two-dimensional liner structure is added into LiFePO4 particles by adopting an alcohol suspension method; a conductive network is formed by the carbon and the Ti3SiC2 together and point-line or point-surface contact is added into pure point-point contact of the contact condition of anode active particles; electrode and electrode/electrolyte interface dynamics is greatly improved, so that low-temperature electrochemical performance of a lithium ion battery is improved. The Ti3SiC2 and carbon composite modified LiFePO4 lithium ion battery anode material adopts a simple process, is low in cost, and is suitable for industrial production.
Description
Technical field
The invention belongs to anode material for lithium-ion batteries technical field, particularly relate to a kind of titanium silicon-carbon (Ti
3siC
2) the lithium ion battery LiFePO 4 (LiFePO composite modified with carbon (C)
4) positive electrode and preparation method thereof.
Background technology
In the situation that global energy and environmental problem are more and more severeer, lithium ion battery is high with its specific energy, good cycle, the feature of environmentally safe becomes the energy storage device of extensive use under normal temperature, can be widely used in the fields such as civil small-scale electrical equipment, electric automobile.A series of, can be used as in anode material for lithium-ion batteries, LiFePO 4 is with its higher theoretical capacity 170mAh/g, charge and discharge platform (3.4V) stably, high-temperature behavior and Heat stability is good, the plurality of advantages such as reversibility is good becomes the electrode material of new generation of tool potentiality.But LiFePO
4conductivity lower, lithium ion migration rate is poor, these shortcomings have not only restricted its application of wider scope at normal temperatures, have equally greatly limited its low temperature electrochemical performance, make in its electrical equipment that can not be applied in cold environment work.Therefore the low temperature charge-discharge performance that improves iron phosphate lithium electrode material itself just becomes the Important Problems that Study on Li-ion batteries using person pays close attention to.The general general reference of low temperature is lower than the temperature range of normal temperature, espespecially lower than 0 ℃.
In order to improve LiFePO
4the cryogenic property of material, researcher mainly studies from several aspects such as doping vario-property, pattern modification and surface modifications both at home and abroad.Wherein, doping vario-property is in building-up process, to add other metal ion, dopant to enter into granule interior to form solid solution, is not affecting LiFePO
4in the situation of material structure, produce distortion of lattice, unit cell volume is expanded, expanded the diffusion admittance of lithium ion, thereby improved lithium ion diffusion rate, comprise the even phosphoric acid position doping of adulterating of the doping of lithium position, iron position.Pattern modification is by improving once or the particle diameter of second particle and pattern, controls the conductivity that reaction specific area improves lithium ion diffusion rate and material.Surface modification refers at LiFePO
4the good carbon of the coated one deck electric conductivity of particle surface, metal oxide etc. or at LiFePO
4in material, add other modified materials.As at LiFePO
4the oxide coated WO of particle surface
2[Liu Shuxin, Yin Hengbo, Wang Haibin, et al.Electrochemical performance of WO
2modified LiFePO
4/ C cathode material for lithium-ion batteries[J], Journal of Alloys and Compounds, 2013,561:129-134], at LiFePO
4in material, add preparing linear nano carbon conductive agent as Chinese invention patent 201110101055.8 or add the good positive pole material of lithium cobalt acid of cryogenic property as Chinese invention patent 201010289760.0.
The present invention adopts the method for surface modification, adds the carbon silicon titanium Ti of lamellar
3siC
2preparation Ti
3siC
2the LiFePO4 LiFePO composite modified with C
4.
Summary of the invention
Object of the present invention is for anode material for lithium-ion batteries LiFePO
4the problem of low temperature electrochemical poor performance, by titanium silicon-carbon (Ti
3siC
2) and the composite modified LiFePO4 (LiFePO of carbon (C)
4), a kind of anode material for lithium-ion batteries with stable cryogenic property is provided.The present invention is a kind of technique composite modifying method simple, with low cost.
It is generally acknowledged, the factor that affects anode material for lithium-ion batteries cryogenic property comprises: limited electrode kinetics; The low conductivity of electrolyte under low temperature; Li
+low diffusion rate and at the high charge transfer resistance R at electrode/electrolyte interface
ct.In the present invention, by titanium silicon-carbon and the composite modified LiFePO4 of carbon, changed Li
+the charge transfer resistance R at the diffusion rate in positive electrode and electrode/electrolyte interface
ctthereby, the cryogenic property of change lithium ion anode material.
The ternary conductivity ceramics Ti of layer structure
3siC
2, existing covalent bond, ionic bond between atom, have again metallic bond, has metal and ceramic general character concurrently.The conductance of block is 4.5 * 10
4s/cm.Ti
3siC
2crystal grain anisotropic growth, the particle finally obtaining is a kind of structure of en plaque.By adopting, in LiFePO4 matrix, add conductivity well to there is again the nano particle Ti of one dimension wire or two-dimensional sheet structure
3siC
2and carbon, the contact situation that both jointly form conductive network and make anodal active particle has increased dotted line by simple some point contact or some face contacts, thereby greatly improve electrode and electrode/electrolyte interface kinetics, improve the diffusion rate of lithium ion, reduce electrochemical impedance R in electrode
ct, improve the cryogenic property of lithium iron phosphate positive material.Ti
3siC
2with the composite modified positive electrode active materials of carbon, the direct contact surface that has reduced active particle and electrolyte is long-pending, has reduced the erosion of electrolyte to anodal active particle, has improved the cyclical stability of electrode.In addition, add Ti
3siC
2the bridge structure of rear formation, in repeated charge process, the lattice constant that can alleviate to a certain extent anodal particle changes, and prevents that crystal is tired, rock-steady structure, raising capacity.
Technical solution of the present invention is as follows:
An anode material for lithium-ion batteries for titanium silicon-carbon and the composite modified LiFePO 4 of carbon, its composition and quality percentage composition are as follows: with the coated LiFePO of C
4powder (is LiFePO
4/ C) be matrix, C content accounts for LiFePO
4the mass percent of+C is 1～10%, Ti
3siC
2content accounts for composite modified powder (LiFePO
4+ C+Ti
3siC
2) gross mass percentage is 0.5～10%.Described method for preparing anode material, it adopts alcohol suspension preparation method, following steps, consists of:
(1) by LiFePO
4/ C powder and Ti
3siC
2powder weighs in proportion, is distributed to respectively and in absolute ethyl alcohol, forms suspension, wherein LiFePO
4/ C suspension quality concentration is 1～10%, Ti
3siC
2suspension quality concentration is 0.1～5%, and sonic oscillation, after 15～60 minutes, continues to stir 1～10 hour under room temperature;
(2) by step (1) gained Ti
3siC
2suspension dropwise joins LiFePO
4in/C suspension, continue under not higher than the heating condition of 60 ℃ to stir to be no less than 6 hours, until ethanol evaporation obtains pastel;
(3) step (2) gained pastel is put into baking oven, at 60 ℃～100 ℃ dry 12 hours, ground afterwards 280 mesh sieves;
(4) gained powder in step (3) is placed in to tube furnace, at nitrogen and hydrogen mixture atmosphere (V
n2: V
h2=95:5) lower 200～600 ℃ of heat treatments are 1～8 hour, again grind, sieve, and obtain the anode material for lithium-ion batteries of the carbon cladded ferrous lithium phosphate of titanium silicon-carbon modification.
Described step (1) LiFePO used
4/ C powder, adopts respectively sol-gal process and carbothermic method to prepare;
Described step (1) Ti used
3siC
2the preparation method of powder is the in-situ reaction that pressure sintering or the Polycarbosilane of take are presoma.
The present invention adopts alcohol suspension method to realize Ti
3siC
2with the composite modified LiFePO of C
4, and add proportioning and technological parameter by the best, obtained the anode material for lithium-ion batteries with good low temperature electrochemical performance.Preparation method's technique of the present invention is simple, is applicable to suitability for industrialized production.
Accompanying drawing explanation
Fig. 1 is embodiment 2 discharge capacity curve chart under 0.1 multiplying power under different temperatures.
Fig. 2 is embodiment 3 at the AC impedance spectrogram of 0 ℃.
Fig. 3 cycle performance curve chart that is embodiment 7 under 0 ℃, 1 multiplying power.
Fig. 4 is the microstructure SEM photo of embodiment 7.
Embodiment
The present invention's initial feed used all adopts the pure raw material of commercially available analysis.
A kind of Ti
3siC
2with the composite modified LiFePO of C
4anode material for lithium-ion batteries, it is characterized in that, with the coated LiFePO of C
4powder (is LiFePO
4/ C) be matrix, wherein C accounts for LiFePO
4the mass percent of/C is 1～10%; Ti
3siC
2accounting for compound coating powder gross mass percentage is 0.5～10%; Adopt the preparation of alcohol suspension method, form Ti
3siC
2with the composite modified LiFePO of C
4composite material (Ti
3siC
2-LiFePO
4/ C).
By Ti
3siC
2-LiFePO
4/ C composite granule is as positive electrode, and acetylene black is conductive agent, and the ptfe emulsion that quality percentage composition is 62.34% (PTFE) is binding agent, and 80:15:5 weighs a certain amount of above-mentioned three kinds of materials in mass ratio.With a small amount of absolute ethyl alcohol, do dispersant, sonic oscillation 15 minutes, then with glass bar, be continuously stirring to bulk, on two roller film laminators, through repeat-rolling, becoming thickness is the film of 140 microns, film is dried 0.5 hour under the condition of 130 ℃ of insulations, and then to obtain diameter be that the positive plate of 12 millimeters is with standby in punching.
In the present invention, all test batteries all adopt 2430 type button cells.Being assembled in of battery is full of in the glove box (relative humidity < 2%) of Ar carries out.Adopting lithium sheet (manufacture of Beijing non-ferrous metal research institute) is negative pole, and electrolyte is 1mol/L LiPF<sub TranNum="171">6</sub>ethylene carbonate (EC) and dimethyl carbonate (DMC) mixed liquor (the two volume ratio is 1:1), with Celgard 2400 microporous polypropylene membranes, make barrier film.Before packed battery, upper and lower cover and pad that packed battery is used are cleaned and are dried with alcohol.The thing that all packed batteries are required is placed and is no less than 4 hours in glove box.The concrete packaging technology of battery is as follows: positive plate is placed on to the central authorities of battery case lower cover, adds the fully wetting positive plate of appropriate electrolyte, then put successively barrier film, and lithium sheet, each several part will guarantee align center, finally puts pad, builds battery case upper cover.The button cell assembling is put into battery mould, with spanner, tighten.The battery that detection installs has or not short circuit phenomenon.Then with sample sack, install button cell and shift out glove box.
Use high accuracy battery Performance Test System (Shenzhen new Weir Electronics Co., Ltd.) battery to be carried out to the tests such as high rate performance, cycle performance, use occasion China electrochemical workstation CHI660C to carry out ac impedance measurement to battery.Constant temperature cryogenic box (Taizhou Hai Hua Electrical Appliances Co., Ltd) provides battery testing low temperature.First at room temperature (25 ℃) 0.1C circulation of mesuring battary 1～3 time, then put 6～10 hours treating that testing temperature is transferred, make it thoroughly reach temperature required balance, it is carried out afterwards the test of charge-discharge magnification performance, cycle performance and AC impedance under assigned temperature.
The LiFePO that the present invention is used
4/ C powder adopts the preparation method of sol-gel method as follows: by 0.018mol Li
3pO
4with 0.036mol H
3pO
4be dissolved in 360mL deionized water, at 70 ℃, stir 1 hour; Separately by 0.054mol FeC
6h
5o
7be dissolved in 540mL deionized water with appropriate oxalic acid, at 60 ℃, stir 1 hour.Two solution are mixed, and at 60 ℃, add thermal agitation until form colloidal sol.Resulting colloidal sol is dried and obtained xerogel at 80 ℃, ground after 80 mesh sieves (V in nitrogen and hydrogen mixture atmosphere
n2: V
h2=95:5) 400 ℃ are incubated 2 hours, then continue to be heated to 600～800 ℃ of insulations 2～8 hours, cross 280 mesh sieves, obtain LiFePO
4/ C anode material for lithium-ion batteries.By changing the content of oxalic acid, can prepare carbonaceous amount percentage composition at 1～10% LiFePO
4/ C powder, for following examples.
The LiFePO that the present invention is used
4/ C powder adopts the preparation method of carbothermic method as follows: by reactant LiOH and FePO
42H
2o weighs by stoichiometric proportion, adds a certain amount of sucrose as reducing agent and carbon source.Take acetone as decentralized medium, in mortar, grind more than 6 hours, after guaranteeing to grind evenly, after it is dried, on forcing press, with certain pressure, carry out compression molding.In nitrogen atmosphere, 600～800 ℃ are incubated 4～10 hours, and 280 mesh sieves are crossed in cooling rear grinding, obtain LiFePO
4/ C anode material for lithium-ion batteries.By changing the content of sucrose, can prepare carbonaceous amount percentage composition at 1～10% LiFePO
4/ C powder, for following examples.
The Ti that the present invention is used
3siC
2powder adopts the preparation method of pressure sintering as follows: by titanium (Ti) powder, silicon (Si) powder, graphite (C) powder and aluminium (Al) powder, be Ti:Si:C:Al=3:1:2:(0.1～0.2 in molar ratio) ratio mixing, add ethanol as medium, put into ball grinder ball milling 4～8 hours.Ball milling disposed slurry is dried at 60 ℃, and grinding is sieved, then the dry mixed raw material after sieving is packed in graphite grinding tool, with the pressure of 8～10MPa by powder compacting.Be placed in afterwards inert atmosphere high temperature furnace, under 1450 ℃, 25MPa pressure, be incubated 2 hours and obtain Ti
3siC
2powder.
The Ti that the present invention is used
3siC
2powder employing Polycarbosilane is that the preparation method of precursor in situ reaction method is as follows: a certain amount of Polycarbosilane is dissolved in organic solvent, then adds a certain proportion of titanium valve or hydride powder, ultrasonic or ball milling mixes it.Carry out afterwards vacuumize, grinding is sieved.By the mixed powder obtaining, in argon gas atmosphere, pyrolysis is 2 hours at 800～1500 ℃, obtains Ti after being cooled to room temperature
3siC
2powder.
Embodiment 1
The LiFePO that adopts carbothermic method to prepare
4/ C(C quality percentage composition 3.58%) powder, as basis material, adopts commercially available Ti
3siC
2powder is as modified material.4.85 grams of basis materials are scattered in to (mass concentration 3.88%) in 120 grams of absolute ethyl alcohols, by the Ti of 0.15 gram
3siC
2be scattered in (mass concentration 0.37%) in 40 grams of absolute ethyl alcohols, by above-mentioned two suspension respectively sonic oscillation after 30 minutes, under room temperature, stir 4 hours.Under vigorous stirring, by Ti
3siC
2suspension dropwise adds LiFePO
4in/C suspension, after dropwising, continue under not higher than the heating condition of 60 ℃ to stir to be no less than 6 hours, until unnecessary ethanol evaporation obtains pastel, be placed on afterwards 70 ℃ of dry 12h in baking oven.By gained powder nitrogen and hydrogen mixture atmosphere (V in tube furnace
n2: V
h2=95:5) lower 400 ℃ of heat treatments are 2 hours, grind, and cross 280 mesh sieves, obtain 3%(quality) Ti
3siC
2the LiFePO of modification
4/ C powder.Adopt this powder for anodal assembling button cell, battery is carried out to cryogenic property test at 0 ℃ ,-10 ℃ and-18 ℃.Discharge capacity in the time of 0 ℃ under 0.1C multiplying power is 114.9mAh/g, and the discharge capacity in the time of-10 ℃ under 0.1C multiplying power is 102.7mAh/g, and the discharge capacity in the time of-18 ℃ under 0.1C multiplying power is 89mAh/g.
Embodiment 2
The LiFePO that adopts carbothermic method to prepare
4/ C(C quality percentage composition 3.58%) powder, as basis material, adopts commercially available Ti
3siC
2powder is as modified material.4.80 grams of basis materials are scattered in to (mass concentration 3.85%) in 120 grams of absolute ethyl alcohols, by the Ti of 0.20 gram
3siC
2be scattered in (mass concentration 0.50%) in 40 grams of absolute ethyl alcohols, by above-mentioned two suspension respectively sonic oscillation after 30 minutes, under room temperature, stir 4 hours.Under vigorous stirring, by Ti
3siC
2suspension dropwise adds LiFePO
4in/C suspension, after dropwising, continue under not higher than the heating condition of 60 ℃ to stir to be no less than 6 hours, until unnecessary ethanol evaporation obtains pastel, be placed on afterwards 70 ℃ of dry 12h in baking oven.By gained powder nitrogen and hydrogen mixture atmosphere (V in tube furnace
n2: V
h2=95:5) lower 400 ℃ of heat treatments are 2 hours, grind, and cross 280 mesh sieves, obtain 4%(quality) Ti
3siC
2the LiFePO of modification
4/ C powder.Adopt this powder for anodal assembling button cell, the battery of assembling is carried out to cryogenic property test at 0 ℃ ,-10 ℃ and-18 ℃.Discharge capacity in the time of 0 ℃ under 0.1C multiplying power is 118.2mAh/g, and the discharge capacity in the time of-10 ℃ under 0.1C multiplying power is 105.4mAh/g, and the discharge capacity in the time of-18 ℃ under 0.1C multiplying power is 94.2mAh/g; And Ti
3siC
2liFePO before modification
4discharge capacity during 0 ℃ of/C material under 0.1 multiplying power is 111.6mAh/g, and the discharge capacity in the time of-10 ℃ under 0.1 multiplying power is 95.8mAh/g, and the discharge capacity in the time of-18 ℃ under 0.1 multiplying power is 75.9mAh/g.Fig. 1 is 4%(quality) Ti
3siC
2positive electrode before and after modification at 0.1 multiplying power discharging capacity, is as can be seen from the figure compared the LiFePO of this modification under different temperatures with positive electrode before modification
4/ C positive electrode all has raising in various degree at 0.1C multiplying power discharging capacity at each temperature, and especially under lower temperature, the improvement of discharge capacity is more obvious.
Embodiment 3
The LiFePO that adopts carbothermic method to prepare
4/ C(C quality percentage composition 3.58%) powder, as basis material, adopts commercially available Ti
3siC
2powder is as modified material.4.80 grams of basis materials are scattered in to (mass concentration 3.85%) in 120 grams of absolute ethyl alcohols, by the Ti of 0.20 gram
3siC
2be scattered in (mass concentration 0.50%) in 40 grams of absolute ethyl alcohols, by above-mentioned two suspension respectively sonic oscillation after 30 minutes, under room temperature, stir 4 hours.Under vigorous stirring, by Ti
3siC
2suspension dropwise adds LiFePO
4in/C suspension, after dropwising, continue under not higher than the heating condition of 60 ℃ to stir to be no less than 6 hours, until unnecessary ethanol evaporation obtains pastel, be placed on afterwards 70 ℃ of dry 12h in baking oven.By gained powder nitrogen and hydrogen mixture atmosphere (V in tube furnace
n2: V
h2=95:5) lower 400 ℃ of heat treatments are 2 hours, grind, and cross 280 mesh sieves, obtain 4%(quality) Ti
3siC
2the LiFePO of modification
4/ C powder.Adopt this powder for anodal assembling button cell, the battery of assembling is carried out to cryogenic property test at 0 ℃ ,-10 ℃ and-18 ℃.Ac impedance measurement shows, the LiFePO of this modification
4after/C powder discharges and recharges under 0.1 multiplying power in 0 ℃, charge transfer resistance is 116.9 Ω, and Ti
3siC
2liFePO before modification
4/ C material in 0 ℃ after 0.1 rate charge-discharge charge transfer resistance be 421.9 Ω.Fig. 2 is ac impedance spectroscopy at 0 ℃, schemes thus visible charge transfer resistance R
ctsignificantly reduce, thereby improved LiFePO
4the cryogenic property of positive electrode.
Embodiment 4
The LiFePO that adopts sol-gal process to prepare
4/ C(C quality percentage composition 10%) powder is as basis material, the Ti that adopts above-mentioned pressure sintering to prepare
3siC
2powder is as modified material.3.98 grams of basis materials are scattered in to (mass concentration 10%) in 35.82 grams of absolute ethyl alcohols, by the Ti of 0.02 gram
3siC
2be scattered in (mass concentration 0.1%) in 19.98 grams of absolute ethyl alcohols, by above-mentioned two suspension respectively sonic oscillation after 15 minutes, under room temperature, stir 10 hours.Under vigorous stirring, by Ti
3siC
2suspension dropwise adds LiFePO
4in/C suspension, after dropwising, continue under not higher than the heating condition of 60 ℃ to stir to be no less than 6 hours, until unnecessary ethanol evaporation obtains pastel, be placed on afterwards 60 ℃ of dry 12h in baking oven.By gained powder nitrogen and hydrogen mixture atmosphere (V in tube furnace
n2: V
h2=95:5) lower 200 ℃ of heat treatments are 8 hours, grind, and cross 280 mesh sieves, obtain 0.5%(quality) Ti
3siC
2the LiFePO of modification
4/ C powder.Adopt this powder for anodal assembling button cell, to carrying out cryogenic property test on 0 ℃, battery ,-10 ℃ and-18 ℃, result shows under Different hypothermia, to have good high rate performance and cycle performance, and ac impedance measurement shows that battery polarization weakens, and Charge-transfer resistance reduces.
Embodiment 5
The LiFePO that adopts carbothermic method to prepare
4/ C(C quality percentage composition 3.58%) powder, as basis material, adopts commercially available Ti
3siC
2powder is as modified material.4.75 grams of basis materials are scattered in to (mass concentration 3.81%) in 120 grams of absolute ethyl alcohols, by the Ti of 0.25 gram
3siC
2be scattered in (mass concentration 0.62%) in 40 grams of absolute ethyl alcohols, by above-mentioned two suspension respectively sonic oscillation after 30 minutes, under room temperature, stir 4 hours.Under vigorous stirring, by Ti
3siC
2suspension dropwise adds LiFePO
4in/C suspension, after dropwising, continue under not higher than the heating condition of 60 ℃ to stir to be no less than 6 hours, until unnecessary ethanol evaporation obtains pastel, be placed on afterwards 70 ℃ of dry 12h in baking oven.By gained powder nitrogen and hydrogen mixture atmosphere (V in tube furnace
n2: V
h2=95:5) lower 400 ℃ of heat treatments are 2 hours, grind, and cross 280 mesh sieves, obtain 5%(quality) Ti
3siC
2the LiFePO of modification
4/ C powder.Adopt this powder for anodal assembling button cell, battery is carried out to cryogenic property test at 0 ℃ ,-10 ℃ and-18 ℃.Discharge capacity in the time of 0 ℃ under 0.1 multiplying power is 114.1mAh/g, and the discharge capacity in the time of-10 ℃ under 0.1 multiplying power is 99.6mAh/g, and the discharge capacity in the time of-18 ℃ under 0.1 multiplying power is 81.5mAh/g.
Embodiment 6
The LiFePO that adopts sol-gal process to prepare
4/ C(C quality percentage composition 1%) powder is as basis material, adopts the above-mentioned Ti prepared by in-situ reaction that Polycarbosilane is presoma of take
3siC
2powder is as modified material.2.7 grams of basis materials are scattered in to (mass concentration 1%) in 267.3 grams of absolute ethyl alcohols, by the Ti of 0.3 gram
3siC
2be scattered in (mass concentration 5%) in 5.7 grams of absolute ethyl alcohols, by above-mentioned two suspension respectively sonic oscillation after 60 minutes, under room temperature, stir 1 hour.Under vigorous stirring, by Ti
3siC
2suspension dropwise adds LiFePO
4in/C suspension, after dropwising, continue under not higher than the heating condition of 60 ℃ to stir to be no less than 6 hours, until unnecessary ethanol evaporation obtains pastel, be placed on afterwards 100 ℃ of dry 12h in baking oven.By gained powder nitrogen and hydrogen mixture atmosphere (V in tube furnace
n2: V
h2=95:5) lower 600 ℃ of heat treatments are 1 hour, grind, and cross 280 mesh sieves, obtain 10%(quality) Ti
3siC
2the LiFePO of modification
4/ C powder.Adopt this powder for anodal assembling button cell, battery is carried out to cryogenic property test at 0 ℃ ,-10 ℃ and-18 ℃, result shows under Different hypothermia, to have good high rate performance and cycle performance, and ac impedance measurement shows that battery polarization weakens, and Charge-transfer resistance reduces.
Embodiment 7
The LiFePO that adopts carbothermic method to prepare
4/ C(C quality percentage composition 4.2%) powder, as basis material, adopts commercially available Ti
3siC
2powder is as modified material.3.84 grams of basis materials are scattered in to (mass concentration 3.1%) in 120 grams of absolute ethyl alcohols, by the Ti of 0.16 gram
3siC
2be scattered in (mass concentration 0.40%) in 40 grams of absolute ethyl alcohols, by above-mentioned two suspension respectively sonic oscillation after 20 minutes, under room temperature, stir 4 hours.Under vigorous stirring, by Ti
3siC
2suspension dropwise adds LiFePO
4in/C suspension, after dropwising, continue under not higher than the heating condition of 60 ℃ to stir to be no less than 6 hours, until unnecessary ethanol evaporation obtains pastel, be placed on afterwards 80 ℃ of dry 12h in baking oven.By gained powder nitrogen and hydrogen mixture atmosphere (V in tube furnace
n2: V
h2=95:5) lower 400 ℃ of heat treatments are 2 hours, grind, and cross 280 mesh sieves, obtain 4%(quality) Ti
3siC
2the LiFePO of modification
4/ C powder.Adopt this powder for anodal assembling button cell, the battery of assembling is carried out to cryogenic property test at 0 ℃ ,-10 ℃ and-18 ℃.Result shows that battery has good high rate performance under Different hypothermia, and the discharge capacity in the time of 0 ℃ under 1 multiplying power is 80.7mAh/g, and after 50 circulations, discharge capacity still can reach 78.5mAh/g, and capability retention is 97.3%; And Ti
3siC
2liFePO before modification
4discharge capacity during 0 ℃ of/C material under 1 multiplying power is 76.5mAh/g, and after 50 circulations, discharge capacity is 72.4mAh/g, and capability retention is 94.6%.Fig. 3 is 4%(quality) Ti
3siC
20 ℃, 1 multiplying power cyclic curve, as can be seen from the figure Ti of powder before and after modification
3siC
2after modification, under battery 1 multiplying power, cycle performance is more stable, and after 20 circulations, capacity is just substantially constant, and capability retention is high; And under battery 1 multiplying power, capacity is in decline in early stage before modification, also there is dipping and heaving in the later stage, and capability retention is lower.Add 4%(quality) Ti
3siC
2after, material cycle performance is at low temperatures improved.Fig. 4 is 4%(quality) Ti
3siC
2the microstructure SEM photo of powder after modification.
The Ti that the present invention proposes
3siC
2with C modified cathode material of lithium LiFePO
4and preparation method thereof, by embodiment, being described, person skilled obviously can be changed content as herein described or suitably change and combination within not departing from content of the present invention, spirit and scope, realizes the present invention.Special needs to be pointed out is, all similar replacements and change apparent to those skilled in the artly, they are deemed to be included in spirit of the present invention, scope and content.
Claims (5)
1. an anode material for lithium-ion batteries for titanium silicon-carbon and the composite modified LiFePO 4 of carbon, is characterized in that composition and quality percentage composition are as follows: with the coated LiFePO of C
4powder is matrix, and C content accounts for LiFePO
4the mass percent of+C is 1～10%, Ti
3siC
2it is 0.5～10% that content accounts for composite modified powder gross mass percentage.
2. material according to claim 1, is characterized in that, described anode material for lithium-ion batteries Ti
3siC
2-LiFePO
4in/C, the nano particle Ti of one dimension wire or two-dimensional sheet structure
3siC
2the situation that contacts that jointly forms conductive network with carbon and make anodal active particle has increased dotted line by simple some point contact or some face contacts, and improves electrode and electrode/electrolyte interface kinetics.
3. material according to claim 1, is characterized in that, the preparation method of described LiFePO4/C powder is carbothermic method or sol-gal process.
4. material according to claim 1, is characterized in that, described Ti
3siC
2the preparation method of powder is the in-situ reaction that pressure sintering or the Polycarbosilane of take are presoma.
5. the preparation method of the positive electrode of claim 1, is characterized in that adopting the preparation of alcohol suspension method, and step is as follows:
(1) by LiFePO
4/ C powder and Ti
3siC
2powder weighs in proportion, is distributed to respectively and in absolute ethyl alcohol, forms suspension, wherein LiFePO
4/ C suspension quality concentration is 1～10%, Ti
3siC
2suspension quality concentration is 0.1～5%, and sonic oscillation, after 15～60 minutes, continues to stir 1～10 hour under room temperature;
(2) by step (1) gained Ti
3siC
2suspension dropwise joins LiFePO
4in/C suspension, continue under not higher than the heating condition of 60 ℃ to stir to be no less than 6 hours, until ethanol evaporation obtains pastel;
(3) step (2) gained pastel is put into baking oven, at 60 ℃～100 ℃ dry 12 hours, ground afterwards 280 mesh sieves;
(4) gained powder in step (3) is placed in to tube furnace, at nitrogen and hydrogen mixture atmosphere (V
n2: V
h2=95:5) lower 200～600 ℃ of heat treatments are 2～8 hours, again grind, sieve, and obtain the anode material for lithium-ion batteries of titanium silicon-carbon and the composite modified LiFePO 4 of carbon.
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103788551A (en) * | 2014-01-14 | 2014-05-14 | 盐城工学院 | Polytetrafluoroethylene composite material and preparation method thereof |
| CN104868121A (en) * | 2015-05-07 | 2015-08-26 | 天津大学 | Graphene-and-carbon-coated lithium iron phosphate lithium ion battery positive electrode material and production method thereof |
| CN105186002A (en) * | 2015-07-13 | 2015-12-23 | 北京理工大学 | Method for improving charge and discharge capacity of lithium ion battery positive electrode material |
| CN106145968A (en) * | 2016-07-02 | 2016-11-23 | 成都育芽科技有限公司 | A kind of preparation method of silicon titanium carbon ceramics nozzle |
| CN109802094A (en) * | 2017-11-15 | 2019-05-24 | 成都特隆美储能技术有限公司 | A kind of low temperature ferric phosphate lithium cell and preparation method thereof |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102723487A (en) * | 2012-06-20 | 2012-10-10 | 天津大学 | LiFePO4 cathode material of lithium ion battery compositely coated by TiN and C and preparation method thereof |
-
2013
- 2013-10-14 CN CN201310479403.4A patent/CN103515600A/en active Pending
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102723487A (en) * | 2012-06-20 | 2012-10-10 | 天津大学 | LiFePO4 cathode material of lithium ion battery compositely coated by TiN and C and preparation method thereof |
Non-Patent Citations (3)
| Title |
|---|
| HONG XIANG ZHAI等: "Oxidation layer in sliding friction surface of high-purity Ti3SiC2", 《JOURNAL OF MATERIALS SCIENCE》, vol. 39, 31 December 2004 (2004-12-31), pages 6635 - 6637, XP001501338, DOI: 10.1023/B:JMSC.0000044910.49066.35 * |
| JING AN 等: "Ti3SiC2 Modified LiFePO4/C Cathode Materials with Improved Electrochemical Performance", 《JOURNAL OF THE ELECTROCHEMICAL SOCIETY》, vol. 159, no. 12, 17 October 2012 (2012-10-17), pages 2038 - 2042 * |
| 罗永明等: "以聚碳硅烷为先驱体原位反应制备 Si-C-Ti 陶瓷", 《稀有金属材料与工程》, vol. 38, no. 2, 31 December 2009 (2009-12-31), pages 415 - 418 * |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103788551A (en) * | 2014-01-14 | 2014-05-14 | 盐城工学院 | Polytetrafluoroethylene composite material and preparation method thereof |
| CN104868121A (en) * | 2015-05-07 | 2015-08-26 | 天津大学 | Graphene-and-carbon-coated lithium iron phosphate lithium ion battery positive electrode material and production method thereof |
| CN105186002A (en) * | 2015-07-13 | 2015-12-23 | 北京理工大学 | Method for improving charge and discharge capacity of lithium ion battery positive electrode material |
| CN106145968A (en) * | 2016-07-02 | 2016-11-23 | 成都育芽科技有限公司 | A kind of preparation method of silicon titanium carbon ceramics nozzle |
| CN109802094A (en) * | 2017-11-15 | 2019-05-24 | 成都特隆美储能技术有限公司 | A kind of low temperature ferric phosphate lithium cell and preparation method thereof |
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