CN103390750B - A kind of preparation method of lithium iron phosphate positive material - Google Patents
A kind of preparation method of lithium iron phosphate positive material Download PDFInfo
- Publication number
- CN103390750B CN103390750B CN201310321004.5A CN201310321004A CN103390750B CN 103390750 B CN103390750 B CN 103390750B CN 201310321004 A CN201310321004 A CN 201310321004A CN 103390750 B CN103390750 B CN 103390750B
- Authority
- CN
- China
- Prior art keywords
- lithium
- inlet pressure
- source gas
- flow
- preparation
- 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
- 239000000463 material Substances 0.000 title claims abstract description 72
- GELKBWJHTRAYNV-UHFFFAOYSA-K lithium iron phosphate Chemical compound [Li+].[Fe+2].[O-]P([O-])([O-])=O GELKBWJHTRAYNV-UHFFFAOYSA-K 0.000 title claims abstract description 21
- 238000002360 preparation method Methods 0.000 title claims abstract description 16
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims abstract description 21
- 229910052799 carbon Inorganic materials 0.000 claims abstract description 21
- 238000005245 sintering Methods 0.000 claims abstract description 20
- 238000000034 method Methods 0.000 claims abstract description 19
- 230000008569 process Effects 0.000 claims abstract description 17
- 230000008021 deposition Effects 0.000 claims abstract description 14
- 239000011247 coating layer Substances 0.000 claims abstract description 12
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 claims abstract description 11
- 239000011204 carbon fibre-reinforced silicon carbide Substances 0.000 claims abstract description 11
- 239000010703 silicon Substances 0.000 claims abstract description 11
- 229910052710 silicon Inorganic materials 0.000 claims abstract description 11
- 238000005019 vapor deposition process Methods 0.000 claims abstract description 10
- 239000007789 gas Substances 0.000 claims description 54
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims description 42
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 claims description 28
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 claims description 24
- 238000010438 heat treatment Methods 0.000 claims description 19
- 229910052757 nitrogen Inorganic materials 0.000 claims description 16
- 229910052786 argon Inorganic materials 0.000 claims description 15
- BLRPTPMANUNPDV-UHFFFAOYSA-N Silane Chemical compound [SiH4] BLRPTPMANUNPDV-UHFFFAOYSA-N 0.000 claims description 14
- XGZVUEUWXADBQD-UHFFFAOYSA-L lithium carbonate Chemical compound [Li+].[Li+].[O-]C([O-])=O XGZVUEUWXADBQD-UHFFFAOYSA-L 0.000 claims description 11
- 229910052808 lithium carbonate Inorganic materials 0.000 claims description 11
- 239000011261 inert gas Substances 0.000 claims description 10
- UHOVQNZJYSORNB-UHFFFAOYSA-N Benzene Chemical compound C1=CC=CC=C1 UHOVQNZJYSORNB-UHFFFAOYSA-N 0.000 claims description 9
- WMFOQBRAJBCJND-UHFFFAOYSA-M Lithium hydroxide Chemical compound [Li+].[OH-] WMFOQBRAJBCJND-UHFFFAOYSA-M 0.000 claims description 9
- YXFVVABEGXRONW-UHFFFAOYSA-N Toluene Chemical compound CC1=CC=CC=C1 YXFVVABEGXRONW-UHFFFAOYSA-N 0.000 claims description 9
- LFVGISIMTYGQHF-UHFFFAOYSA-N ammonium dihydrogen phosphate Chemical compound [NH4+].OP(O)([O-])=O LFVGISIMTYGQHF-UHFFFAOYSA-N 0.000 claims description 9
- 229910000387 ammonium dihydrogen phosphate Inorganic materials 0.000 claims description 9
- 238000000498 ball milling Methods 0.000 claims description 9
- 238000001816 cooling Methods 0.000 claims description 9
- 239000002270 dispersing agent Substances 0.000 claims description 9
- 239000006185 dispersion Substances 0.000 claims description 9
- 229940062993 ferrous oxalate Drugs 0.000 claims description 9
- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 9
- OWZIYWAUNZMLRT-UHFFFAOYSA-L iron(2+);oxalate Chemical compound [Fe+2].[O-]C(=O)C([O-])=O OWZIYWAUNZMLRT-UHFFFAOYSA-L 0.000 claims description 9
- 230000014759 maintenance of location Effects 0.000 claims description 9
- 235000019837 monoammonium phosphate Nutrition 0.000 claims description 9
- 238000001291 vacuum drying Methods 0.000 claims description 9
- CSCPPACGZOOCGX-UHFFFAOYSA-N Acetone Chemical compound CC(C)=O CSCPPACGZOOCGX-UHFFFAOYSA-N 0.000 claims description 8
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims description 7
- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 claims description 7
- 238000013461 design Methods 0.000 claims description 7
- 229910052744 lithium Inorganic materials 0.000 claims description 7
- OTMSDBZUPAUEDD-UHFFFAOYSA-N Ethane Chemical compound CC OTMSDBZUPAUEDD-UHFFFAOYSA-N 0.000 claims description 6
- HSFWRNGVRCDJHI-UHFFFAOYSA-N alpha-acetylene Natural products C#C HSFWRNGVRCDJHI-UHFFFAOYSA-N 0.000 claims description 6
- 125000002534 ethynyl group Chemical group [H]C#C* 0.000 claims description 6
- PQXKHYXIUOZZFA-UHFFFAOYSA-M lithium fluoride Chemical compound [Li+].[F-] PQXKHYXIUOZZFA-UHFFFAOYSA-M 0.000 claims description 6
- ABTOQLMXBSRXSM-UHFFFAOYSA-N silicon tetrafluoride Chemical compound F[Si](F)(F)F ABTOQLMXBSRXSM-UHFFFAOYSA-N 0.000 claims description 6
- CZMRCDWAGMRECN-UGDNZRGBSA-N Sucrose Chemical compound O[C@H]1[C@H](O)[C@@H](CO)O[C@@]1(CO)O[C@@H]1[C@H](O)[C@@H](O)[C@H](O)[C@@H](CO)O1 CZMRCDWAGMRECN-UGDNZRGBSA-N 0.000 claims description 5
- 229930006000 Sucrose Natural products 0.000 claims description 5
- 239000005720 sucrose Substances 0.000 claims description 5
- WQZGKKKJIJFFOK-GASJEMHNSA-N Glucose Natural products OC[C@H]1OC(O)[C@H](O)[C@@H](O)[C@@H]1O WQZGKKKJIJFFOK-GASJEMHNSA-N 0.000 claims description 4
- 239000012298 atmosphere Substances 0.000 claims description 4
- WQZGKKKJIJFFOK-VFUOTHLCSA-N beta-D-glucose Chemical compound OC[C@H]1O[C@@H](O)[C@H](O)[C@@H](O)[C@@H]1O WQZGKKKJIJFFOK-VFUOTHLCSA-N 0.000 claims description 4
- 239000003822 epoxy resin Substances 0.000 claims description 4
- 239000008103 glucose Substances 0.000 claims description 4
- 229920001568 phenolic resin Polymers 0.000 claims description 4
- 239000005011 phenolic resin Substances 0.000 claims description 4
- 229920000647 polyepoxide Polymers 0.000 claims description 4
- VGGSQFUCUMXWEO-UHFFFAOYSA-N Ethene Chemical compound C=C VGGSQFUCUMXWEO-UHFFFAOYSA-N 0.000 claims description 3
- 239000004698 Polyethylene Substances 0.000 claims description 3
- PZPGRFITIJYNEJ-UHFFFAOYSA-N disilane Chemical compound [SiH3][SiH3] PZPGRFITIJYNEJ-UHFFFAOYSA-N 0.000 claims description 3
- 239000001307 helium Substances 0.000 claims description 3
- 229910052734 helium Inorganic materials 0.000 claims description 3
- SWQJXJOGLNCZEY-UHFFFAOYSA-N helium atom Chemical compound [He] SWQJXJOGLNCZEY-UHFFFAOYSA-N 0.000 claims description 3
- XIXADJRWDQXREU-UHFFFAOYSA-M lithium acetate Chemical compound [Li+].CC([O-])=O XIXADJRWDQXREU-UHFFFAOYSA-M 0.000 claims description 3
- -1 polyethylene Polymers 0.000 claims description 3
- 229920000573 polyethylene Polymers 0.000 claims description 3
- 238000009413 insulation Methods 0.000 claims description 2
- 239000003595 mist Substances 0.000 claims description 2
- 229910010707 LiFePO 4 Inorganic materials 0.000 abstract description 26
- HBBGRARXTFLTSG-UHFFFAOYSA-N Lithium ion Chemical compound [Li+] HBBGRARXTFLTSG-UHFFFAOYSA-N 0.000 abstract description 12
- 238000000151 deposition Methods 0.000 abstract description 12
- 229910001416 lithium ion Inorganic materials 0.000 abstract description 12
- 238000007740 vapor deposition Methods 0.000 abstract description 6
- 238000005229 chemical vapour deposition Methods 0.000 abstract description 3
- 230000004048 modification Effects 0.000 abstract description 3
- 238000012986 modification Methods 0.000 abstract description 3
- 238000012545 processing Methods 0.000 abstract description 3
- 230000015572 biosynthetic process Effects 0.000 abstract description 2
- 238000003786 synthesis reaction Methods 0.000 abstract description 2
- 239000011164 primary particle Substances 0.000 abstract 1
- 229910001873 dinitrogen Inorganic materials 0.000 description 10
- 230000000052 comparative effect Effects 0.000 description 7
- 229910052493 LiFePO4 Inorganic materials 0.000 description 5
- 238000007599 discharging Methods 0.000 description 5
- 239000012071 phase Substances 0.000 description 4
- 239000013078 crystal Substances 0.000 description 3
- 238000005516 engineering process Methods 0.000 description 3
- 239000012299 nitrogen atmosphere Substances 0.000 description 3
- 238000011160 research Methods 0.000 description 3
- 229910000077 silane Inorganic materials 0.000 description 3
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 2
- 150000001485 argon Chemical class 0.000 description 2
- 230000008901 benefit Effects 0.000 description 2
- 238000004146 energy storage Methods 0.000 description 2
- 230000006872 improvement Effects 0.000 description 2
- 239000002245 particle Substances 0.000 description 2
- 239000002033 PVDF binder Substances 0.000 description 1
- 239000011149 active material Substances 0.000 description 1
- 239000010405 anode material Substances 0.000 description 1
- 230000004888 barrier function Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 239000001569 carbon dioxide Substances 0.000 description 1
- 229910002092 carbon dioxide Inorganic materials 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 239000008358 core component Substances 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000009792 diffusion process Methods 0.000 description 1
- 239000006181 electrochemical material Substances 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 125000005842 heteroatom Chemical group 0.000 description 1
- 150000002500 ions Chemical class 0.000 description 1
- 239000010410 layer Substances 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 229920002981 polyvinylidene fluoride Polymers 0.000 description 1
- 230000001681 protective effect Effects 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 238000003746 solid phase reaction Methods 0.000 description 1
- 230000002194 synthesizing effect Effects 0.000 description 1
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
Landscapes
- Battery Electrode And Active Subsutance (AREA)
Abstract
The invention discloses a kind of preparation method of lithium iron phosphate positive material.The method is for the existing modification weak point of LiFePO 4 material, drive before the synthesis in body and add a certain amount of carbon source in conjunction with introducing carbon-source gas and silicon source gas in sintering process, utilize the method for chemical vapour deposition (CVD) at LiFePO 4 material surface uniform deposition one deck SiC coating layer, realize the preparation that surface has the LiFePO 4 material of even SiC/C coating layer.By the inlet pressure of carbon source, silicon source gas in carbon source addition in adjustment presoma and vapor deposition processes, flow and vapor deposition times in building-up process, obtain the lithium iron phosphate positive material that surface has uniform C/SiC coating layer.This material has less primary particle size, and surface has the C/SiC coating layer of one deck uniform close, has higher tap density, and it has good rate charge-discharge performance, and processing characteristics is excellent.Be with a wide range of applications in power lithium-ion battery field.
Description
Technical field
The present invention relates to electrochemical material preparation and new energy field, particularly relate to a kind of preparation method of lithium iron phosphate positive material.
Background technology
Along with increasingly sharpening of energy crisis, new renewable resource is all being found in the whole world, and renewable resource such as solar energy, wind energy, tidal energy, geothermal energy etc. have the advantages that region drinks timeliness.Make full use of these resources, need intelligent grid or large-scale energy-storage system.Lithium ion battery has good application prospect as energy storage electromotive force.On the other hand, the exhaustion day by day of fossil energy forces people to develop hybrid electrically or pure electric vehicle, and its core component battery becomes research emphasis.Lithium ion is its higher energy density compared with other batteries, good fail safe and longer useful life and to be standbyly popular.
LiFePO 4 material is as anode material for lithium-ion batteries, and the advantage such as, Heat stability is good moderate with its abundant raw material, cheap, environmental protection, operating voltage, causes the extensive concern of people.
Through years of researches development, its performance obtains obvious improvement, but LiFePO4 still exists ionic conductance and all lower problem of electron conductivity, poor-performing during high power charging-discharging.The current study on the modification to LiFePO 4 material is mainly through following several mode: (1) nanometer process, and the crystallite dimension reducing synthesizing iron lithium phosphate can improve the ionic conductance of LiFePO4.Crystal grain radius is less, and the solid-state diffusion process of lithium ion in ion is shorter, and Lithium-ion embeding is deviate from easier; (2) element doping, in material lattice, introducing hetero-atoms is to improve the conductivity of material, but still portion is clear at present for its feasibility and working mechanism, and DeGrain, also can reduce along with the increase capacity along with element doping amount; (3) conductive doped dose, can improve the electronic conductivity of material, major part adopts carbon coating technology, and because of material with carbon element complex forms, the LiFePO 4 material tap density after most of carbon is coated can reduce greatly, and processing characteristics can be subject to certain impact.
Study on the modification about LiFePO 4 material is many, but does not also find to add carbon source at present in presoma in conjunction with vapour deposition SiC in sintering process to synthesize small particle diameter and to have the research of the LiFePO 4 material of SiC/C carbon coating layer closely.
Summary of the invention
The technical problem to be solved in the present invention is to provide a kind of preparation method of lithium iron phosphate positive material.
In order to solve the problems of the technologies described above, the technical solution used in the present invention is: a kind of preparation method of lithium iron phosphate positive material, it is characterized in that comprising the following steps:
1) take lithium source, ferrous oxalate, ammonium dihydrogen phosphate, organic carbon source according to mol ratio Li: Fe: P: C=1.02: 1: 1: 0.2 ~ 0.5, with alcohol or acetone for dispersant carries out ball milling dispersion treatment, then carry out vacuum drying treatment and obtain presoma;
2) under described presoma being placed in tube furnace 550 DEG C of conditions, carry out pre-burning under nitrogen protection, heating rate 5 DEG C/min, temperature retention time 5 hours, room temperature is down in cooling naturally, carries out coarse crushing to Preburning material;
3) Preburning material through coarse crushing is placed in tube furnace and carries out double sintering, under inert gas shielding, rise to 700-750 DEG C with the heating rate of 5 DEG C/min, insulation 8-15 hour; In temperature-rise period, inert gas inlet pressure is 0.15MPa, and flow is 0.1L/min; After temperature reaches design temperature, it is coated that introducing carbon-source gas and silicon source gas carry out vapour deposition, carbon-source gas inlet pressure 0.1 ~ 0.2MPa in vapor deposition processes, and flow is 0.04 ~ 0.12L/min; Silicon source gas inlet pressure 0.1 ~ 0.2MPa, flow is 0.04 ~ 0.12L/min; Regulate inert gas inlet pressure 0.1 ~ 0.2MPa, flow is 0.04 ~ 0.12L/min simultaneously; After vapour deposition 30min-240min, close carbon-source gas and silicon source gas air inlet, keep inert gas inlet pressure 0.15MPa, flow is 0.1L/min; Under this inert atmosphere, complete remaining sintering process, and naturally cool to room temperature, namely obtain the lithium iron phosphate positive material with surface C/SiC coating layer.
As preferably, step 1) described in lithium source be the combination of a kind of in lithium carbonate, lithium hydroxide, lithium acetate, lithium fluoride or at least two kinds; Described organic carbon source is the combination of a kind of in glucose, sucrose, phenolic resins, epoxy resin or polyethylene or at least two kinds.
, step 3 preferred as another) described in carbon-source gas be the combination of a kind of in methane, ethane, ethene, acetylene, benzene, toluene or at least two kinds; Described silicon source gas be monosilane, disilane, a kind of or combination of at least two kinds in silicon tetrafluoride.
Also have one preferably, step 3) described in inert gas be the mist of a kind of in helium, nitrogen and argon gas or at least two kinds.
The invention has the beneficial effects as follows:
Be combined in presoma and add carbon source and introduce SiC by chemical vapor deposition processes in follow-up heat treatment process, effectively inhibit growing up of crystal grain in conventional solid course of reaction, achieve at LiFePO 4 material coated with uniform C/SiC layer, this material has excellent rate charge-discharge performance and processing characteristics.
Accompanying drawing explanation
Below in conjunction with the drawings and specific embodiments, the present invention is further detailed explanation.
Fig. 1 be preparation method's embodiment 3 of lithium iron phosphate positive material of the present invention obtain LiFePO 4 material TEM figure.
Fig. 2 be in preparation method's embodiment 3 of lithium iron phosphate positive material of the present invention obtain LiFePO 4 material SEM figure.
Fig. 3 be in preparation method's embodiment 3 of lithium iron phosphate positive material of the present invention to obtain in LiFePO 4 material and comparative example obtain LiFePO 4 material 0.2C multiplying power under to discharge curve comparison figure.
In figure, a is C/SiC vapour deposition coated LiFePO 4 for lithium ion batteries, and b is carbon-coated LiFePO 4 for lithium ion batteries, and c is SiC vapour deposition coated LiFePO 4 for lithium ion batteries, and d is pure phase LiFePO4.
Fig. 4 be in preparation method's embodiment 3 of lithium iron phosphate positive material of the present invention obtain the rate discharge curves figure of LiFePO 4 material.
Embodiment
Embodiment 1
1) taking lithium carbonate, ferrous oxalate, ammonium dihydrogen phosphate, sucrose according to mol ratio Li: Fe: P: C=1.02: 1: 1: 0.2, is that dispersant carries out ball milling dispersion treatment 5 hours with alcohol, then carries out vacuum drying treatment acquisition presoma; Under above-mentioned obtained dry presoma being placed in tube furnace 550 DEG C of conditions, carry out pre-burning under nitrogen protection, heating rate 5 DEG C/min, temperature retention time 5 hours, room temperature is down in cooling naturally, carries out coarse crushing to Preburning material;
2) above-mentioned the obtained Preburning material through coarse crushing is placed in tube furnace and carries out double sintering, rise to 700 DEG C with the heating rate of 5 DEG C/min under nitrogen protection, be incubated 10 hours.In temperature-rise period, nitrogen inlet pressure is 0.15MPa, and flow is 0.1L/min.After temperature reaches design temperature, it is coated that introducing methane gas and monosilane gas carry out vapour deposition, methane gas inlet pressure 0.1MPa in vapor deposition processes, flow is 0.12L/min, monosilane gas inlet pressure 0.1MPa, flow is 0.12L/min, and regulate nitrogen inlet pressure 0.1MPa, flow is 0.04L/min simultaneously.After vapor deposition times 30min, close methane gas and monosilane gas inlet, keep nitrogen inlet pressure 0.15MPa, flow is 0.1L/min, remaining sintering process is completed under this nitrogen atmosphere, and naturally cool to room temperature, namely obtain the lithium iron phosphate positive material with surface C/SiC coating layer.The tap density of this material is 1.05g/cm
3.
Embodiment 2
1) taking lithium carbonate, ferrous oxalate, ammonium dihydrogen phosphate, glucose according to mol ratio Li: Fe: P: C=1.02: 1: 1: 0.3, is that dispersant carries out ball milling dispersion treatment 5 hours with acetone, then carries out vacuum drying treatment acquisition presoma; Under above-mentioned obtained dry presoma being placed in tube furnace 550 DEG C of conditions, carry out pre-burning under argon shield, heating rate 5 DEG C/min, temperature retention time 5 hours, room temperature is down in cooling naturally, carries out coarse crushing to Preburning material;
2) above-mentioned the obtained Preburning material through coarse crushing is placed in tube furnace and carries out double sintering, under argon shield, rise to 720 DEG C with the heating rate of 5 DEG C/min, be incubated 10 hours.In temperature-rise period, argon inlet pressure is 0.15MPa, and flow is 0.1L/min.After temperature reaches design temperature, it is coated that introducing ethane gas and b silane gas carry out vapour deposition, ethane gas inlet pressure 0.12MPa in vapor deposition processes, flow is 0.1L/min, b silane gas inlet pressure 0.12MPa, flow is 0.1L/min, and regulate argon inlet pressure 0.1MPa, flow is 0.08L/min simultaneously.After vapor deposition times 60min, close ethane gas and b silane gas air inlet, keep argon inlet pressure 0.15MPa, flow is 0.1L/min, remaining sintering process is completed under this argon gas atmosphere, and naturally cool to room temperature, namely obtain the lithium iron phosphate positive material with surface C/SiC coating layer.The tap density of this material is 1.1g/cm
3.
Embodiment 3
1) taking lithium carbonate, ferrous oxalate, ammonium dihydrogen phosphate, phenolic resins according to mol ratio Li: Fe: P: C=1.02: 1: 1: 0.35, is that dispersant carries out ball milling dispersion treatment 5 hours with alcohol, then carries out vacuum drying treatment acquisition presoma; Under above-mentioned obtained dry presoma being placed in tube furnace 550 DEG C of conditions, carry out pre-burning under nitrogen protection, heating rate 5 DEG C/min, temperature retention time 5 hours, room temperature is down in cooling naturally, carries out coarse crushing to Preburning material;
2) above-mentioned the obtained Preburning material through coarse crushing is placed in tube furnace and carries out double sintering, rise to 740 DEG C with the heating rate of 5 DEG C/min under nitrogen protection, be incubated 10 hours.In temperature-rise period, nitrogen gas inlet pressure is 0.15MPa, and flow is 0.1L/min.After temperature reaches design temperature, it is coated that introducing methane gas and monosilane gas carry out vapour deposition, methane gas inlet pressure 0.12MPa in vapor deposition processes, flow is 0.08L/min, monosilane gas inlet pressure 0.12MPa, flow is 0.08L/min, and regulate nitrogen gas inlet pressure 0.1MPa, flow is 0.1L/min simultaneously.After vapor deposition times 120min, close methane gas and monosilane gas inlet, keep nitrogen gas inlet pressure 0.15MPa, flow is 0.1L/min, remaining sintering process is completed under this nitrogen atmosphere, and naturally cool to room temperature, namely obtain the lithium iron phosphate positive material with surface C/SiC coating layer.The tap density of this material is 1.3g/cm
3, respectively as shown in Figure 1 and Figure 2, half-cell charging and discharging curve as shown in Figure 3 for TEM and SEM of the LiFePO 4 material obtained.
Embodiment 4
1) taking lithium carbonate, ferrous oxalate, ammonium dihydrogen phosphate, epoxy resin according to mol ratio Li: Fe: P: C=1.02: 1: 1: 0.5, is that dispersant carries out ball milling dispersion treatment 5 hours with acetone, then carries out vacuum drying treatment acquisition presoma; Under above-mentioned obtained dry presoma being placed in tube furnace 550 DEG C of conditions, carry out pre-burning under argon shield, heating rate 5 DEG C/min, temperature retention time 5 hours, room temperature is down in cooling naturally, carries out coarse crushing to Preburning material;
2) above-mentioned the obtained Preburning material through coarse crushing is placed in tube furnace and carries out double sintering, under argon shield, rise to 740 DEG C with the heating rate of 5 DEG C/min, be incubated 10 hours.In temperature-rise period, argon inlet pressure is 0.15MPa, and flow is 0.1L/min.After temperature reaches design temperature, it is coated that introducing acetylene gas and silicon tetrafluoride gas carry out vapour deposition, acetylene gas inlet pressure 0.2MPa in vapor deposition processes, flow is 0.04L/min, silicon tetrafluoride gas inlet pressure 0.2MPa, flow is 0.04L/min, and regulate argon inlet pressure 0.1MPa, flow is 0.1L/min simultaneously.After vapor deposition times 220min, close acetylene gas and silicon tetrafluoride gas air inlet, keep argon inlet pressure 0.15MPa, flow is 0.1L/min, remaining sintering process is completed under this argon gas atmosphere, and naturally cool to room temperature, namely obtain the lithium iron phosphate positive material with surface C/SiC coating layer.The tap density of this material is 1.1g/cm
3.
Comparative example 1
1) taking lithium carbonate, ferrous oxalate, ammonium dihydrogen phosphate, sucrose according to mol ratio Li: Fe: P: C=1.02: 1: 1: 0.35, is that dispersant carries out ball milling dispersion treatment 5 hours with alcohol, then carries out vacuum drying treatment acquisition presoma; Under above-mentioned obtained dry presoma being placed in tube furnace 550 DEG C of conditions, carry out pre-burning under nitrogen protection, heating rate 5 DEG C/min, temperature retention time 5 hours, room temperature is down in cooling naturally, carries out coarse crushing to Preburning material;
2) above-mentioned the obtained Preburning material through coarse crushing is placed in tube furnace and carries out double sintering, under nitrogen gas protection, rise to 740 DEG C with the heating rate of 5 DEG C/min, be incubated 10 hours.In process, nitrogen gas inlet pressure is 0.15MPa, and flow is 0.1L/min.And naturally cool to room temperature, namely obtain the carbon-coated LiFePO 4 for lithium ion batteries positive electrode without vapor deposition processes.The tap density of this material is 0.85g/cm
3.
Comparative example 2
1) taking lithium carbonate, ferrous oxalate, ammonium dihydrogen phosphate according to mol ratio Li: Fe: P=1.02: 1: 1, is that dispersant carries out ball milling dispersion treatment 5 hours with alcohol, then carries out vacuum drying treatment acquisition presoma; Under above-mentioned obtained dry presoma being placed in tube furnace 550 DEG C of conditions, carry out pre-burning under nitrogen protection, heating rate 5 DEG C/min, temperature retention time 5 hours, room temperature is down in cooling naturally, carries out coarse crushing to Preburning material;
2) above-mentioned the obtained Preburning material through coarse crushing is placed in tube furnace and carries out double sintering, rise to 740 DEG C with the heating rate of 5 DEG C/min under nitrogen protection, be incubated 10 hours.In temperature-rise period, nitrogen gas inlet pressure is 0.15MPa, and flow is 0.1L/min.After temperature reaches design temperature, it is coated that introducing methane gas and monosilane gas carry out vapour deposition, methane gas inlet pressure 0.12MPa in vapor deposition processes, flow is 0.08L/min, monosilane gas inlet pressure 0.12MPa, flow is 0.08L/min, and regulate nitrogen gas inlet pressure 0.1MPa, flow is 0.1L/min simultaneously.After vapor deposition times 120min, close methane gas and monosilane gas inlet, keep nitrogen gas inlet pressure 0.15MPa, flow is 0.1L/min, remaining sintering process is completed under this nitrogen atmosphere, and naturally cool to room temperature, namely obtain the lithium iron phosphate positive material with surperficial SiC coating layer.The tap density of this material is 1.15g/cm
3.
Comparative example 3
1) taking lithium carbonate, ferrous oxalate, ammonium dihydrogen phosphate according to mol ratio Li: Fe: P=1.02: 1: 1, is that dispersant carries out ball milling dispersion treatment 5 hours with alcohol, then carries out vacuum drying treatment acquisition presoma; Under above-mentioned obtained dry presoma being placed in tube furnace 550 DEG C of conditions, carry out pre-burning under nitrogen protection, heating rate 5 DEG C/min, temperature retention time 5 hours, room temperature is down in cooling naturally, carries out coarse crushing to Preburning material;
2) above-mentioned the obtained Preburning material through coarse crushing is placed in tube furnace and carries out double sintering, under nitrogen gas protection, rise to 740 DEG C with the heating rate of 5 DEG C/min, be incubated 10 hours.In process, nitrogen gas inlet pressure is 0.15MPa, and flow is 0.1L/min.And naturally cool to room temperature, namely obtain the pure phase lithium iron phosphate positive material obtained through solid phase reaction.The tap density of this material is 1.0g/cm
3.
The LiFePO 4 material obtained in above-described embodiment and comparative example is assembled into button cell, in pole piece, active material matching ratio is LiFeP04: SP: PVDF=80: 10: 10, adopt Clgard2300 type barrier film, be metal lithium sheet to electrode, discharge with 0.2C, 1C, 4C, 5C multiplying power respectively, rate of charge is fixed as 0.2C, and charging/discharging voltage scope is 2.0-4.0V.The C/SiC that embodiment 3 and comparative example 1, example 2, example 3 obtain is coated, C is coated, SiC is coated and the charging and discharging curve of the LiFePO 4 material of pure phase as shown in Figure 3.
Embodiment and comparative example's result show: the synthesis of LiFePO 4 material, by adding organic carbon source in presoma, and carry out CVD vapor deposition processes in follow-up sintering process, effectively inhibit on the one hand growing up of crystal grain in sintering process, synthesize the LiFePO4 of small particle diameter, achieve the C/CSi on LiFePO 4 material surface closely coated on the other hand, efficiently solve the problem that simple carbon-coated LiFePO 4 for lithium ion batteries material tap density is low.Compared with and pure phase LiFePO 4 material coated with carbon-coated LiFePO 4 for lithium ion batteries, vapour deposition SiC, there is higher specific discharge capacity and excellent multiplying power discharging property.
In above-described embodiment, organic carbon source to the situation listing sucrose, select other organic carbon sources as glucose, phenolic resins, epoxy resin and polyethylene and this organic carbon source the experimental result that produces be similar; In embodiment, lithium source, to the situation listing lithium carbonate, selects other lithium sources such as lithium hydroxide, lithium acetate, lithium fluoride to create similar experimental result to lithium carbonate; Other carbon-source gas such as methane, ethane, ethene, acetylene, benzene, toluene is selected to create similar experimental result; select other silicon source gas as disilane, silicon tetrafluoride creates similar experimental result, selects other protective gas such as helium, argon gas, carbon dioxide to create similar experimental result to nitrogen.
Above-described embodiment of the present invention, does not form limiting the scope of the present invention.Any amendment done within the spirit and principles in the present invention, equivalent replacement and improvement etc., all should be included within claims of the present invention.
Claims (4)
1. a preparation method for lithium iron phosphate positive material, is characterized in that comprising the following steps:
1) take lithium source, ferrous oxalate, ammonium dihydrogen phosphate, organic carbon source according to mol ratio Li: Fe: P: C=1.02: 1: 1: 0.2 ~ 0.5, with alcohol or acetone for dispersant carries out ball milling dispersion treatment, then carry out vacuum drying treatment and obtain presoma;
2) under described presoma being placed in tube furnace 550 DEG C of conditions, carry out pre-burning under nitrogen protection, heating rate 5 DEG C/min, temperature retention time 5 hours, room temperature is down in cooling naturally, carries out coarse crushing to Preburning material;
3) Preburning material through coarse crushing is placed in tube furnace and carries out double sintering, under inert gas shielding, rise to 700-750 DEG C with the heating rate of 5 DEG C/min, insulation 8-15 hour; In temperature-rise period, inert gas inlet pressure is 0.15MPa, and flow is 0.1L/min; After temperature reaches design temperature, it is coated that introducing carbon-source gas and silicon source gas carry out vapour deposition, carbon-source gas inlet pressure 0.1 ~ 0.2MPa in vapor deposition processes, and flow is 0.04 ~ 0.12L/min; Silicon source gas inlet pressure 0.1 ~ 0.2MPa, flow is 0.04 ~ 0.12L/min; Regulate inert gas inlet pressure 0.1 ~ 0.2MPa, flow is 0.04 ~ 0.12L/min simultaneously; After vapour deposition 30min-240min, close carbon-source gas and silicon source gas air inlet, keep inert gas inlet pressure 0.15MPa, flow is 0.1L/min; Under this inert atmosphere, complete remaining sintering process, and naturally cool to room temperature, namely obtain the lithium iron phosphate positive material with surface C/SiC coating layer.
2. preparation method according to claim 1, is characterized in that: step 1) described in lithium source be the combination of a kind of in lithium carbonate, lithium hydroxide, lithium acetate, lithium fluoride or at least two kinds; Described organic carbon source is the combination of a kind of in glucose, sucrose, phenolic resins, epoxy resin or polyethylene or at least two kinds.
3. preparation method according to claim 1, is characterized in that: step 3) described in carbon-source gas be the combination of a kind of in methane, ethane, ethene, acetylene, benzene, toluene or at least two kinds; Described silicon source gas be monosilane, disilane, a kind of or combination of at least two kinds in silicon tetrafluoride.
4. preparation method according to claim 1, is characterized in that: step 3) described in inert gas be the mist of a kind of in helium, nitrogen and argon gas or at least two kinds.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310321004.5A CN103390750B (en) | 2013-07-26 | 2013-07-26 | A kind of preparation method of lithium iron phosphate positive material |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310321004.5A CN103390750B (en) | 2013-07-26 | 2013-07-26 | A kind of preparation method of lithium iron phosphate positive material |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN103390750A CN103390750A (en) | 2013-11-13 |
| CN103390750B true CN103390750B (en) | 2015-08-05 |
Family
ID=49534958
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201310321004.5A Active CN103390750B (en) | 2013-07-26 | 2013-07-26 | A kind of preparation method of lithium iron phosphate positive material |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN103390750B (en) |
Families Citing this family (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103794788B (en) * | 2014-02-21 | 2016-01-20 | 合肥国轩高科动力能源有限公司 | Surface carbon coating method of lithium iron phosphate anode material |
| CN103956488B (en) * | 2014-04-17 | 2016-05-25 | 四会市达博文实业有限公司 | A kind of radio frequency plasma strengthens chemical vapour deposition (CVD) and realizes the coated method of LiFePO4 conductive layer |
| CN105609716A (en) * | 2015-12-21 | 2016-05-25 | 宁波高新区锦众信息科技有限公司 | Preparation method for carbon-silicon coated lithium iron phosphate composite material for lithium ion battery |
| CN105514380A (en) * | 2015-12-21 | 2016-04-20 | 宁波高新区锦众信息科技有限公司 | Preparation method of LiFeSiO composite material for Li-ion batteries |
| CN108039466B (en) * | 2017-12-05 | 2020-07-17 | 合肥国轩高科动力能源有限公司 | Preparation method of titanium silicide coated lithium iron phosphate composite material |
| KR102131262B1 (en) * | 2018-08-14 | 2020-08-05 | 울산과학기술원 | an anode active material, a method of preparing the anode active material, and Lithium secondary battery comprising an anode including the anode active material |
| CN111133614B (en) * | 2019-12-30 | 2024-02-23 | 上海杉杉科技有限公司 | Silicon-based negative electrode material, preparation method thereof and lithium ion battery |
| WO2024229788A1 (en) * | 2023-05-11 | 2024-11-14 | 广东邦普循环科技有限公司 | Method for repairing and regenerating positive electrode material by recovering waste battery in full-chain integrated manner |
| CN117154068B (en) * | 2023-10-31 | 2024-07-16 | 宁德时代新能源科技股份有限公司 | Positive electrode active material, preparation method thereof, positive electrode plate, secondary battery and power utilization device |
Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1741301A (en) * | 2005-09-09 | 2006-03-01 | 贵州新材料矿业发展有限公司 | Process for producing lithium ion battery anode material ferrtilithium phosphate |
| CN101217195A (en) * | 2007-12-28 | 2008-07-09 | 龚思源 | A lithium ion battery anode material of lithium iron phosphate and the corresponding vapor deposition and cladding method of conductive network |
| CN101533912A (en) * | 2008-03-11 | 2009-09-16 | 比亚迪股份有限公司 | Method for preparing lithium iron phosphate used as positive active material of lithium ion secondary battery |
| WO2011069348A1 (en) * | 2009-12-11 | 2011-06-16 | 中国科学院宁波材料技术与工程研究所 | Lithium iron phosphate positive electrode active material modified by graphene, preparation method and lithium ion secondary battery thereof |
| CN102347475A (en) * | 2010-07-27 | 2012-02-08 | 曾永斌 | High-performance lithium ion battery and preparation process thereof |
| CN102522547A (en) * | 2011-12-28 | 2012-06-27 | 彩虹集团公司 | Preparation method for lithium ion fast conductor modified lithium iron phosphate material |
| CN102664247A (en) * | 2012-04-01 | 2012-09-12 | 上海锦众信息科技有限公司 | Method for preparing LiFePO4/SiC lithium battery positive plate by microwave heating |
| CN103151521A (en) * | 2013-02-22 | 2013-06-12 | 中国科学院过程工程研究所 | Positive electrode material of lithium ion battery and preparing method thereof |
| CN103187569A (en) * | 2013-03-31 | 2013-07-03 | 复旦大学 | Preparation method for LiFePO4/C contained anode material for lithium ion battery |
-
2013
- 2013-07-26 CN CN201310321004.5A patent/CN103390750B/en active Active
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1741301A (en) * | 2005-09-09 | 2006-03-01 | 贵州新材料矿业发展有限公司 | Process for producing lithium ion battery anode material ferrtilithium phosphate |
| CN101217195A (en) * | 2007-12-28 | 2008-07-09 | 龚思源 | A lithium ion battery anode material of lithium iron phosphate and the corresponding vapor deposition and cladding method of conductive network |
| CN101533912A (en) * | 2008-03-11 | 2009-09-16 | 比亚迪股份有限公司 | Method for preparing lithium iron phosphate used as positive active material of lithium ion secondary battery |
| WO2011069348A1 (en) * | 2009-12-11 | 2011-06-16 | 中国科学院宁波材料技术与工程研究所 | Lithium iron phosphate positive electrode active material modified by graphene, preparation method and lithium ion secondary battery thereof |
| CN102347475A (en) * | 2010-07-27 | 2012-02-08 | 曾永斌 | High-performance lithium ion battery and preparation process thereof |
| CN102522547A (en) * | 2011-12-28 | 2012-06-27 | 彩虹集团公司 | Preparation method for lithium ion fast conductor modified lithium iron phosphate material |
| CN102664247A (en) * | 2012-04-01 | 2012-09-12 | 上海锦众信息科技有限公司 | Method for preparing LiFePO4/SiC lithium battery positive plate by microwave heating |
| CN103151521A (en) * | 2013-02-22 | 2013-06-12 | 中国科学院过程工程研究所 | Positive electrode material of lithium ion battery and preparing method thereof |
| CN103187569A (en) * | 2013-03-31 | 2013-07-03 | 复旦大学 | Preparation method for LiFePO4/C contained anode material for lithium ion battery |
Also Published As
| Publication number | Publication date |
|---|---|
| CN103390750A (en) | 2013-11-13 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN103390750B (en) | A kind of preparation method of lithium iron phosphate positive material | |
| CN110838576B (en) | A kind of doped coated sodium ion battery cathode material and preparation method and use thereof | |
| CN103227324B (en) | Preparation method of iron oxide cathode material for lithium ion battery | |
| CN114122352B (en) | Silicon-carbon negative electrode material for porous carbon doped induced silicon deposition and preparation method thereof | |
| CN107331851B (en) | Sodium-ion battery nano-chip arrays nickel phosphide/3D graphene composite material and preparation method thereof | |
| CN102306781A (en) | Doped graphene electrode material, macro preparation method and application of doped graphene electrode material | |
| CN109004199A (en) | A kind of preparation method of sodium-ion battery cathode biomass hard carbon material | |
| CN100434362C (en) | A method for preparing silicon/lithium-rich phase composite negative electrode materials for lithium secondary batteries by high-energy ball milling | |
| CN104752698A (en) | Silicon carbon composite material for lithium ion battery cathode, and preparation method of composite material | |
| CN105047892A (en) | Porous silicon material, and preparation method and application thereof | |
| WO2018209912A1 (en) | Tin sulfide/sulfur/few-layer graphene composite material, preparation method therefor and application thereof | |
| CN103794761B (en) | Preparation method of silicon/lithium titanate composite negative electrode material of lithium ion battery | |
| JP4497622B2 (en) | Anode material for lithium secondary battery | |
| WO2018095202A1 (en) | Composite lithium battery and preparation method therefor | |
| CN103413920B (en) | A kind of lithium ion battery silicon/aligned carbon nanotube composite negative pole material and preparation method thereof | |
| CN107768607B (en) | Preparation method of lithium ion battery negative electrode material | |
| CN104409712A (en) | Preparation method of carbon and nitrogen coated lithium titanate material | |
| CN109309191A (en) | A kind of novel long-life energy storage lithium ion battery pole piece and lithium ion battery | |
| CN104966814A (en) | High-security metallic lithium cathode and preparation method thereof | |
| CN109830662A (en) | A kind of phosphorus doping nanometer silicon lithium ion battery cathode material and preparation method thereof | |
| CN102887504B (en) | A kind of preparation method of carbon material for lithium ion battery cathode | |
| CN106876684A (en) | A kind of lithium battery silicium cathode material, negative plate and the lithium battery prepared with it | |
| CN105958027B (en) | A kind of manganese base composite positive pole and preparation method thereof | |
| CN103326020A (en) | Process for preparing lithium iron phosphate composite cathode material | |
| CN104300113A (en) | Carbon-coated lithium iron oxide ion battery electrode and preparation method and application thereof |
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 | ||
| C56 | Change in the name or address of the patentee | ||
| CP03 | Change of name, title or address |
Address after: 230000 Yaohai Industrial Zone, Hefei New District, Anhui, No. D weft Road, No. 7 Patentee after: Gotion High-tech Co., Ltd. Address before: 230000 Yaohai Industrial Park, Anhui, Hefei No. D weft Road, No. 7 Patentee before: Hefei Guoxuan High-Tech Power Energy Co.,Ltd. |
|
| C41 | Transfer of patent application or patent right or utility model | ||
| TR01 | Transfer of patent right |
Effective date of registration: 20160517 Address after: 215300 Kunshan City, Suzhou Province, Yushan City, the town of Yuan Feng Road, No. 100, No. Patentee after: GUOXUAN NEW ENERGY (SUZHOU) CO.,LTD. Address before: 230000 Yaohai Industrial Zone, Hefei New District, Anhui, No. D weft Road, No. 7 Patentee before: Gotion High-tech Co., Ltd. |
|
| TR01 | Transfer of patent right |
Effective date of registration: 20200330 Address after: No.98 Hexing East Road, Nantong Development Zone, 226000 Jiangsu Province Patentee after: Shanghai Electric GuoXuan new energy technology (Nantong) Co.,Ltd. Address before: 215300, No. 100, Feng Feng Road, Yushan Town, Kunshan, Jiangsu, Suzhou Patentee before: GUOXUAN NEW ENERGY (SUZHOU) Co.,Ltd. |
|
| TR01 | Transfer of patent right |