CN108987687B - Low-temperature lithium ion battery graphite negative electrode material and preparation method thereof - Google Patents
Low-temperature lithium ion battery graphite negative electrode material and preparation method thereof Download PDFInfo
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Abstract
The invention relates to a graphite cathode material of a low-temperature lithium ion battery and a preparation method thereof. The graphite cathode material of the low-temperature lithium ion battery comprises graphite and a fast ion conductor coated on the surface of the graphite; the fast ion conductor has a higher oxidation-reduction potential than graphite. The preparation method comprises the following steps: carrying out wet ball milling on original graphite powder, drying the mixed solution into powder by using a spray dryer to obtain graphite powder with smaller particle size, carrying out intercalation reaction on the graphite powder, and then carrying out surface coating to obtain the graphite cathode material for the low-temperature lithium ion battery. In the structure of the negative electrode material, the particle size of graphite can be controlled, the lithium ion diffusion distance is shortened, the distance between graphite layers is increased after intercalation, the ion diffusion capacity of the electrode material at low temperature can be obviously improved, the overall conductivity can be improved by metal or high-conductivity substances inserted between the graphite layers, a fast ion conductor is coated on the surface of graphite, a stable and uniform SEI film can be generated, the lithium ion diffusion capacity is improved, and the interface performance at low temperature is improved. The material can also be used as an ideal cathode material of a sodium-ion battery and a high-performance super capacitor material.
Description
Technical Field
The invention relates to the field of lithium ion battery materials, in particular to a preparation method and application of a graphite cathode material of a low-temperature lithium ion battery.
Background
At present, the problem of environmental pollution is increasingly serious, and the reduction of the combustion of fossil fuels is one of the problems which need to be solved urgently in the society at present. High energy density high power density lithium ion battery technology has attracted considerable attention over the last few years because of its potential for use in the hybrid and electric vehicle fields. As commercial graphite negative electrode material, Li at charging+When embedding the graphite material, it is first desolvated,this process consumes a certain amount of energy, hindering Li+Diffusing into the graphite; and at low temperature, the SEI film has larger impedance, the dynamic characteristic of the graphite cathode is poor, especially in the charging process, the electrochemical polarization of the cathode is obviously intensified, metallic lithium is easily separated out to form lithium dendrite, the diaphragm is broken through, the anode and the cathode are short-circuited, and potential safety hazards are caused.
At present, the research aiming at the modification of low-temperature graphite mainly comprises surface coating, wherein a layer of soft carbon or hard carbon or lithium titanate and other materials are coated on the surface of graphite powder to improve the interface performance of the graphite powder. However, these methods do not improve the lithium ion diffusibility at low temperatures.
Disclosure of Invention
The invention provides a low-temperature lithium ion battery graphite cathode material and a preparation method thereof, the material is used as the lithium ion battery cathode material at low temperature, has better electrochemical performance, and the preparation method of the material is simple, easy to operate and easy for industrial production.
The invention relates to a graphite cathode material of a low-temperature lithium ion battery, which comprises the following components in percentage by weight: the graphite cathode material of the low-temperature lithium ion battery comprises graphite and a fast ion conductor coated on the surface of the graphite; the fast ion conductor has a higher oxidation-reduction potential than graphite.
As a preferred scheme, the invention relates to a graphite cathode material of a low-temperature lithium ion battery; the graphite cathode material of the low-temperature lithium ion battery consists of intercalated graphite, a graphite interlayer conductor and a fast ion conductor coated on the surface of the graphite.
The invention relates to a graphite cathode material of a low-temperature lithium ion battery; the graphite interlayer conductor is formed by converting an intercalation in the sintering process; the intercalation is selected from at least one of aniline, pyrrole, tin salt, cobalt salt, ferric salt, nickel salt and manganese salt;
the tin salt is at least one selected from chloride salt, acetate, sulfate and nitrate of tin;
the cobalt salt is at least one selected from cobalt chloride, cobalt acetate, cobalt sulfate and cobalt nitrate;
the iron salt is at least one selected from iron chloride, iron acetate, iron sulfate and iron nitrate;
the nickel salt is selected from at least one of nickel chloride, nickel acetate, nickel sulfate and nickel nitrate;
the manganese salt is selected from at least one of manganese chloride salt, manganese acetate, manganese sulfate and manganese nitrate. In industrial application, tin salt, cobalt salt, iron salt, nickel salt and manganese salt are directly converted into corresponding metals after being sintered. The aniline and pyrrole are sintered and then directly converted into conductive carbon.
Preferably, the graphite interlayer conductor is at least one selected from zero-valent tin, zero-valent cobalt and zero-valent nickel.
The invention relates to a graphite cathode material of a low-temperature lithium ion battery; the fast ion conductor comprises LiM2(PO4)3And/or with LiM2(PO4)3A series of doping products which are precursors, wherein M is at least one selected from Zr, Sc, Ti and Ge; wherein the doped element is at least one of Si, Al, La, Mg, Zn, Sn, Fe, Mn, Co, Ni, Cu, W, Mo, V and Cr.
The invention relates to a graphite cathode material of a low-temperature lithium ion battery; the fast ion conductor is coated on the surface of graphite to form a coating layer with the thickness of 1-10 nm.
The invention relates to a preparation method of a graphite cathode material of a low-temperature lithium ion battery; the method comprises the following steps:
using intercalated graphite as a raw material; preparing intercalation graphite into a solution, and adding a lithium source, an M source, a doping element and a phosphorus source; coating a layer of fast ion conductor on the intercalated graphite by adopting a hydrothermal method or a solvothermal method; then washing, drying and sintering to obtain the low-temperature lithium ion battery graphite cathode material; the M source provides at least one element of Zr, Sc, Ti and Ge with non-zero valence; the doping element is at least one selected from Si, Al, La, Mg, Zn, Sn, Fe, Mn, Co, Ni, Cu, W, Mo, V and Cr.
The invention relates to a preparation method of a graphite cathode material of a low-temperature lithium ion battery, when an M source is a titanium source; the titanium source is tetrabutyl titanate or isopropyl titanate.
The invention relates to a preparation method of a graphite cathode material of a low-temperature lithium ion battery, wherein a phosphorus source is selected from at least one of diammonium hydrogen phosphate, ammonium dihydrogen phosphate and phosphoric acid.
The invention relates to a preparation method of a graphite cathode material of a low-temperature lithium ion battery, wherein a lithium source is selected from at least one of lithium hydroxide, lithium carbonate, lithium acetate and lithium nitrate.
The invention relates to a preparation method of a graphite cathode material of a low-temperature lithium ion battery, which comprises the steps of preparing intercalated graphite into a solution, and adding a lithium source, an M source, a doping element and a phosphorus source to obtain an intercalated graphite composite material solution; in the intercalation graphite composite material solution, the molar ratio of lithium, M and phosphorus is 1-1.5: 2: 3-4; the mass ratio of M to graphite in the intercalated graphite is 1-20: 100, respectively; the mol ratio of the doping elements to M is 0-5: 10;
the invention relates to a preparation method of a graphite cathode material of a low-temperature lithium ion battery, which is characterized in that when a layer of fast ion conductor is coated on intercalated graphite by a hydrothermal method or a solvothermal method, the temperature is controlled to be 160-230 ℃ and the time is 6-48 h. When the intercalation graphite is coated with a layer of fast ion conductor by a hydrothermal method, the solvent is deionized water or a mixture of water and at least one of absolute ethyl alcohol, ethylene glycol and acetone. When the intercalation graphite is coated with a layer of fast ion conductor by the solvothermal method, the solvent is at least one of absolute ethyl alcohol, glycol and acetone.
The invention relates to a preparation method of a graphite cathode material of a low-temperature lithium ion battery, wherein a detergent is ethanol or deionized water for 2-6 times. Drying at 60-150 ℃ for 6-24 h;
the invention relates to a preparation method of a graphite cathode material of a low-temperature lithium ion battery, wherein during sintering, a protective atmosphere is adopted for sintering; the protective atmosphere is selected from one of argon atmosphere, nitrogen atmosphere and vacuum atmosphere. The temperature rise rate is controlled to be 1-10 ℃/min during sintering, the sintering temperature is 600-900 ℃, and the heat preservation time at the sintering temperature is 4-24 h.
As a preferred scheme, the invention relates to a preparation method of a graphite cathode material of a low-temperature lithium ion battery; the intercalated graphite is prepared by the following steps:
step one
Adding graphite powder into a ball mill, carrying out wet stirring ball milling, and carrying out spray drying on the mixed solution;
step two
Mixing the graphite powder obtained in the step one with concentrated acid, and then carrying out ultrasonic stirring and centrifugal drying to obtain graphite oxide;
step three
Preparing the graphite oxide obtained in the step two into a solution, adding an intercalation material and a reducing agent, washing and filtering the solution after ultrasonic dispersion, and carrying out heat treatment on a filtered product to obtain an intercalation graphite material.
The invention relates to a preparation method of a graphite cathode material of a low-temperature lithium ion battery, wherein in the first step, a ball-milling solvent is selected from deionized water or absolute ethyl alcohol; and adding a solvent to form a slurry, wherein the mass fraction of graphite in the slurry is 30-70%.
The invention relates to a preparation method of a graphite cathode material of a low-temperature lithium ion battery, wherein in the step one, graphite powder is one of natural graphite, artificial graphite or mesocarbon microbeads; the particle size is 30-100 microns.
The invention relates to a preparation method of a graphite cathode material of a low-temperature lithium ion battery, wherein in the step one, the ball milling time is 4-24h, and the ball milling rotating speed is 200-400 r/min; when a spray dryer is used, the air inlet temperature is 200-300 ℃ and the air outlet temperature is 100-150 ℃; the prepared graphite has the granularity of 1-20 um.
The invention relates to a preparation method of a graphite cathode material of a low-temperature lithium ion battery, wherein in the second step, the concentrated acid is one of hydrochloric acid or nitric acid, and the concentration of the concentrated acid is 0.5-3 mol/L; ultrasonically stirring for 3-24 h; the drying temperature is 60-200 ℃.
The invention relates to a preparation method of a graphite cathode material of a low-temperature lithium ion battery, which comprises the step three that the intercalation materials are chloride, acetate, sulfate and nitrate of aniline, pyrrole or metal tin, cobalt, iron, nickel and manganese. The intercalation materials are converted to graphite intercalation materials during sintering.
The invention relates to a preparation method of a graphite cathode material of a low-temperature lithium ion battery, wherein in the third step, a reducing agent is hydrazine hydrate, D-sodium erythorbate, sodium sulfite, hydroxylamine or sodium borohydride;
the invention relates to a preparation method of a graphite cathode material of a low-temperature lithium ion battery, which comprises the steps of ultrasonically dispersing for 1-12h in the third step; washing the solution to pH 6-8; the temperature rise rate of the tubular furnace is 1-10 ℃/min, the temperature is 180-; the atmosphere is at least one selected from the group consisting of an argon atmosphere, a nitrogen atmosphere, an argon-hydrogen atmosphere, a carbon dioxide atmosphere, a hydrogen atmosphere, and a nitrogen dioxide atmosphere.
The invention designs and prepares the graphite cathode material of the low-temperature lithium ion battery; after the battery is assembled, under the discharge condition of 0.2C, the capacity retention rate of 200 cycles of circulation at the temperature of-20 ℃ is more than or equal to 94 percent. The capacity retention rate of 200 cycles at-40 ℃ is more than or equal to 93 percent.
Principles and advantages
The diffusion performance of lithium ions has a direct relation with the particle size of graphite, the ball milling method is one of the most commonly used methods for reducing the particle size of substances at present, the graphite interlayer spacing can be enlarged and the lithium ion diffusion capacity can be improved by intercalating graphite, and high-conductivity substances such as metal, conductive carbon and the like can greatly enhance the graphite conductivity. The fast ion conductor has ion conductivity comparable to that of liquid electrolyte, and has stable SEI film and raised ion diffusion capacity, and the redox potential of the fast ion conductor is higher than that of graphite, so as to avoid the generation of lithium dendrite and raise safety.
Drawings
FIG. 1 is a 0.2C discharge curve of the lithium titanium phosphate coated metallic nickel intercalated graphite composite material obtained in example 1 of the present invention at different temperatures;
FIG. 2 is a cycle curve at-20 ℃ of the lithium titanium phosphate coated metallic nickel intercalated graphite composite material obtained in example 1 according to the present invention;
FIG. 3 is a 0.2C discharge curve of the lithium titanium phosphate coated graphite composite material obtained in example 4 according to the present invention at different temperatures;
FIG. 4 is a 0.2C discharge voltage-capacity curve at different temperatures for the metallic nickel-intercalated graphite composite material obtained in comparative example 1;
FIG. 5 is a 0.2C discharge curve of the graphite negative electrode material of the present invention in comparative example 3 at different temperatures;
FIG. 6 is a cycle curve at-20 ℃ of the graphite negative electrode material obtained in comparative example 3 according to the present invention;
fig. 1 shows that the graphite material in example 1 has very small variations of open-circuit discharge voltage and plateau voltage with temperature, and the capacity retention ratio of the system at-40 ℃ is 93.5%, so that the graphite material has very excellent low-temperature performance. And it can be seen from the cycling curve of fig. 2 that the capacity retention rate is still maintained at about 95% after 200 cycles at-20 ℃.
It can be seen from fig. 3 that the open circuit voltage and plateau voltage of the graphite material in example 4 have very small changes with temperature above-30 ℃, decrease at-40 ℃ and have good low-temperature performance.
It can be seen from fig. 4 that the discharge curve of the graphite material in comparative example 1 decreases more rapidly with decreasing temperature, and the low temperature performance is slightly inferior.
From fig. 5, it can be seen that the battery performance at low temperature is directly reduced, the capacity retention rate is only 1.4% at-40C, which indicates that the material has very poor low-temperature performance, and from the cycle curve of fig. 6, it can be seen that the capacity retention rate is rapidly reduced after being cycled for dozens of circles at-20C.
Detailed Description
The preparation process of the positive plate comprises the following steps: LiCoO as positive electrode material2With PVDF, SP, KS-6 (LiCoO in mass ratio)2: PVDF: SP: KS-6 ═ 94.5: 2.5: 2: 1) is slowly mixed for 0.5h by a double-planet stirrer, and then the solid-liquid ratio is 74%: adding NMP with a certain mass into 26 percent of the mixture, and stirring for 6 hours to prepare pulp; passing the prepared slurry through a coater according to a size of 20mg cm-2Is uniformly coated on an aluminum foil with a thickness of 16 mu m, dried and then rolled, wherein LiCoO2The compacted density (mass per unit volume after flat pressing) of the system is 3.9g cm-3。
The preparation process of the negative plate comprises the following steps: mixing the prepared graphite material with CMC, SBR and SP (graphite: CMC:SBR: SP 92.5: 1.6: 2.4: 3.5) is slowly mixed for 0.5h by a double-planet mixer, and then the solid-liquid ratio is 52%: adding deionized water with a certain mass into 48%, and stirring for 6h to prepare pulp; uniformly coating the prepared slurry on a copper foil with the thickness of 8 mu m by a coating machine according to the mass per unit area of the corresponding positive electrode with 8 percent of additional capacity for the first time, drying and rolling, wherein the compaction density (the mass per unit volume after flat pressing and compaction) of graphite is 1.55g cm-3。
Assembling the battery: cut, weld the utmost point ear positive and negative pole piece, pass through the coiling machine with positive plate, negative pole piece and diaphragm and twine into the book heart of certain width and thickness, the winding principle is: the positive electrode and the negative electrode are isolated by a diaphragm, the positive electrode and the negative electrode are wrapped by the isolating diaphragm in the width direction, and the positive electrode is wrapped by the negative electrode; then the roll core is put into an aluminum plastic film which is punched and formed according to the proper size for wrapping, the top edge and the side edge are heat-sealed on a packaging machine, and the flaring of the air bag belt is reserved; baking the packaged battery in a vacuum oven at 85 ℃ for 24h, and taking the battery into a glove box for liquid injection, infiltration and pre-sealing after the battery is completely baked; and then standing for 24 hours in a high-temperature room at 45 ℃, putting the battery which is well stood into a constant-temperature constant-pressure forming cabinet for primary charging, charging to 3.8V, performing air-pumping sealing after the SEI film in the battery is generated and side reaction is finished, cutting off an air bag belt, and finishing the assembly of the soft-packaged lithium ion full-battery.
Example 1
Weighing 10g of natural graphite powder, dissolving in 20mL of deionized water, uniformly stirring, placing in a ball milling tank, ball milling for 12 hours at the rotating speed of 400r/min, and granulating the ball-milled slurry by using a spray dryer, wherein the air inlet temperature is 220 ℃ and the air outlet temperature is 120 ℃; and preparing graphite powder. Graphite powder is mixed with 1 mol/L30 mL hydrochloric acid, the mixture is ultrasonically stirred for 12 hours, then both sides of the mixture are washed by deionized water, and then the mixture is dried at 100 ℃ to obtain graphite oxide. Adding graphite oxide into 50mL of ethanol solution, adding a nickel acetate intercalation substance and a sodium borohydride reducing agent, ultrasonically dispersing for 6 hours, washing with the ethanol solution until the pH value is 7, carrying out heat treatment on a filtered product, heating to 300 ℃ at a heating rate of 5 ℃/min in a tubular furnace argon-hydrogen atmosphere, and keeping the temperature for 6 hours to obtain a metal nickel intercalation graphite material; adding metallic nickel intercalated graphite into 80mL of ethanol solution, and mixing according to the molar ratio of lithium to titanium to phosphorus of 1.5: 2: and 3.5, adding lithium acetate, tetrabutyl titanate and phosphoric acid according to the proportion, wherein the mass of tetrabutyl titanate is 5 percent of that of graphite powder, weighing, mixing to obtain a mixed solution, the hydrothermal temperature is 200 ℃, the hydrothermal time is 24 hours, washing a hydrothermal product twice by using ethanol, drying in an oven at 80 ℃ for 12 hours, introducing argon into a tubular furnace for sintering, heating to 900 ℃ at the heating rate of 5 ℃/min, and keeping the temperature for 8 hours to obtain the titanium lithium phosphate coated metal nickel intercalated graphite composite material.
Example 2
Weighing 10g of natural graphite powder, dissolving in 20mL of deionized water, uniformly stirring, placing in a ball milling tank, ball milling for 12 hours at the rotating speed of 400r/min, and granulating the ball-milled slurry by using a spray dryer, wherein the air inlet temperature is 220 ℃ and the air outlet temperature is 120 ℃; and preparing graphite powder. Graphite powder is mixed with 1 mol/L30 mL hydrochloric acid, the mixture is ultrasonically stirred for 12 hours, then both sides of the mixture are washed by deionized water, and then the mixture is dried at 100 ℃ to obtain graphite oxide. Adding graphite oxide into 50mL of ethanol solution, adding a nickel acetate intercalation substance and a sodium borohydride reducing agent, ultrasonically dispersing for 6 hours, washing with the ethanol solution until the pH value is 7, carrying out heat treatment on a filtered product, heating to 300 ℃ at a heating rate of 5 ℃/min in a tubular furnace argon-hydrogen atmosphere, and keeping the temperature for 6 hours to obtain a metal nickel intercalation graphite material; adding metallic nickel intercalated graphite into 80mL of ethanol solution, and mixing according to the molar ratio of lithium to titanium to phosphorus of 1: 2: 3, adding lithium acetate, tetrabutyl titanate and phosphoric acid, wherein the mass of tetrabutyl titanate is 2% of that of graphite powder, weighing, mixing to obtain a mixed solution, the hydrothermal temperature is 200 ℃, the hydrothermal time is 24 hours, washing a hydrothermal product twice by using ethanol, drying in an oven at 80 ℃ for 12 hours, introducing argon into a tubular furnace for sintering, heating to 900 ℃ at the heating rate of 5 ℃/min, and keeping the temperature for 8 hours to obtain the lithium titanium phosphate coated metal nickel intercalated graphite composite material. The material had a reduced coated lithium titanium phosphate layer compared to the final product in example 1, with slightly poorer performance at-40 degrees.
Example 3
Weighing 10g of natural graphite powder, dissolving in 20mL of deionized water, uniformly stirring, placing in a ball milling tank, ball milling for 12 hours at the rotating speed of 400r/min, and granulating the ball-milled slurry by using a spray dryer, wherein the air inlet temperature is 220 ℃ and the air outlet temperature is 120 ℃; and preparing graphite powder. Graphite powder is mixed with 1 mol/L30 mL hydrochloric acid, the mixture is ultrasonically stirred for 12 hours, then both sides of the mixture are washed by deionized water, and then the mixture is dried at 100 ℃ to obtain graphite oxide. Adding graphite oxide into 50mL of ethanol solution, adding a nickel acetate intercalation substance and a sodium borohydride reducing agent, ultrasonically dispersing for 6 hours, washing with the ethanol solution until the pH value is 7, carrying out heat treatment on a filtered product, heating to 300 ℃ at a heating rate of 5 ℃/min in a tubular furnace argon-hydrogen atmosphere, and keeping the temperature for 6 hours to obtain a metal nickel intercalation graphite material; adding metallic nickel intercalated graphite into 80mL of ethanol solution, and mixing according to the molar ratio of lithium to titanium to phosphorus of 1.5: 2: 4, adding lithium acetate, tetrabutyl titanate and phosphoric acid according to the proportion, wherein the mass of tetrabutyl titanate is 20% of that of graphite powder, weighing, mixing to obtain a mixed solution, the hydrothermal temperature is 200 ℃, the hydrothermal time is 24 hours, washing a hydrothermal product twice by using ethanol, drying in an oven at 80 ℃ for 12 hours, introducing argon into a tubular furnace for sintering, heating to 900 ℃ at the heating rate of 5 ℃/min, and keeping the temperature for 8 hours to obtain the lithium titanium phosphate coated metal nickel intercalated graphite composite material. The material has a thicker layer of coated lithium titanium phosphate than the final product in example 1, and the performance is slightly worse at-30 to-40 degrees.
Example 4
Weighing 10g of natural graphite powder, dissolving in 20mL of deionized water, uniformly stirring, placing in a ball milling tank, ball milling for 12 hours at the rotating speed of 400r/min, and granulating the ball-milled slurry by using a spray dryer, wherein the air inlet temperature is 220 ℃ and the air outlet temperature is 120 ℃; and preparing graphite powder. Adding graphite powder into 80mL of ethanol solution, and mixing according to the molar ratio of lithium to titanium to phosphorus of 1.5: 2: and 3.5, adding lithium acetate, tetrabutyl titanate and phosphoric acid according to the proportion, wherein the mass of tetrabutyl titanate is 5 percent of that of graphite powder, weighing, mixing to obtain a mixed solution, washing a hydrothermal product twice by using ethanol, drying the hydrothermal product in an oven at the temperature of 80 ℃ for 12 hours, introducing argon into a tubular furnace for sintering, heating to 900 ℃ at the temperature rise rate of 5 ℃/min, and keeping the temperature for 8 hours to obtain the lithium titanium phosphate coated graphite composite material.
Comparative example 1
Weighing 10g of natural graphite powder, dissolving in 20mL of deionized water, uniformly stirring, placing in a ball milling tank, ball milling for 12 hours at the rotating speed of 400r/min, and granulating the ball-milled slurry by using a spray dryer, wherein the air inlet temperature is 220 ℃ and the air outlet temperature is 120 ℃; and preparing graphite powder. Graphite powder is mixed with 1 mol/L30 mL hydrochloric acid, the mixture is ultrasonically stirred for 12 hours, then both sides of the mixture are washed by deionized water, and then the mixture is dried at 100 ℃ to obtain graphite oxide. Adding graphite oxide into 50mL of ethanol solution, adding a nickel acetate intercalation substance and a sodium borohydride reducing agent, ultrasonically dispersing for 6h, washing with the ethanol solution until the pH value is 7, carrying out heat treatment on a filtered product, heating to 300 ℃ at a heating rate of 5 ℃/min in a tubular furnace argon-hydrogen atmosphere, and keeping the temperature for 6h to obtain the metallic nickel intercalation graphite material.
Comparative example 2
Weighing 10g of natural graphite powder, dissolving in 20mL of deionized water, uniformly stirring, placing in a ball milling tank, ball milling for 12 hours at the rotating speed of 400r/min, and granulating the ball-milled slurry by using a spray dryer, wherein the air inlet temperature is 220 ℃ and the air outlet temperature is 120 ℃; and preparing graphite powder. Graphite powder is mixed with 1 mol/L30 mL hydrochloric acid, the mixture is ultrasonically stirred for 12 hours, then both sides of the mixture are washed by deionized water, and then the mixture is dried at 100 ℃ to obtain graphite oxide. Adding graphite oxide into 50mL of ethanol solution, adding a nickel acetate intercalation substance and a sodium borohydride reducing agent, ultrasonically dispersing for 6 hours, washing with the ethanol solution until the pH value is 7, carrying out heat treatment on a filtered product, heating to 300 ℃ at a heating rate of 5 ℃/min in a tubular furnace argon-hydrogen atmosphere, and keeping the temperature for 6 hours to obtain a metal nickel intercalation graphite material; adding metallic nickel intercalated graphite into 80mL of ethanol solution, and mixing according to the molar ratio of lithium to titanium to phosphorus of 1.5: 2: and 3.5, adding lithium acetate, tetrabutyl titanate and phosphoric acid according to the proportion, wherein the mass of tetrabutyl titanate is 40 percent of that of graphite powder, weighing, mixing to obtain a mixed solution, the hydrothermal temperature is 200 ℃, the hydrothermal time is 24 hours, washing a hydrothermal product twice by using ethanol, drying in an oven at 80 ℃ for 12 hours, introducing argon into a tubular furnace for sintering, heating to 900 ℃ at the heating rate of 5 ℃/min, and keeping the temperature for 8 hours to obtain the titanium lithium phosphate coated metal nickel intercalated graphite composite material. The material coated with lithium titanium phosphate was too thick compared to the final product in example 1, comparable in proportion to graphite, and had a very low capacity.
Comparative example 3:
the natural graphite powder is not processed at all and is directly used as a negative electrode material.
Claims (3)
1. A graphite cathode material of a low-temperature lithium ion battery; the method is characterized in that: the graphite cathode material of the low-temperature lithium ion battery consists of intercalated graphite, a graphite interlayer conductor and a fast ion conductor coated on the surface of the graphite; the oxidation-reduction potential of the fast ion conductor is higher than that of graphite;
the graphite interlayer conductor is formed by converting an intercalation in the sintering process; the intercalation is selected from at least one of aniline, pyrrole, tin salt, cobalt salt, ferric salt, nickel salt and manganese salt;
the tin salt is at least one selected from chloride salt, acetate, sulfate and nitrate of tin;
the cobalt salt is at least one selected from cobalt chloride, cobalt acetate, cobalt sulfate and cobalt nitrate;
the iron salt is at least one selected from iron chloride, iron acetate, iron sulfate and iron nitrate;
the nickel salt is selected from at least one of nickel chloride, nickel acetate, nickel sulfate and nickel nitrate;
the manganese salt is selected from at least one of manganese chloride salt, manganese acetate, manganese sulfate and manganese nitrate;
the fast ion conductor comprises LiM2(PO4)3And/or with LiM2(PO4)3A series of doping products which are precursors, wherein M is at least one selected from Zr, Sc, Ti and Ge; wherein the doped element is at least one of Si, Al, La, Mg, Zn, Sn, Fe, Mn, Co, Ni, Cu, W, Mo, V and Cr;
the fast ion conductor is coated on the surface of the graphite to form a coating layer with the thickness of 1-10 nm;
after the graphite cathode material of the low-temperature lithium ion battery is assembled into the battery, under the discharge condition of 0.2C, the capacity retention rate of 200 cycles of circulation is more than or equal to 94% at the temperature of-20 ℃, and the capacity retention rate of 200 cycles of circulation is more than or equal to 93% at the temperature of-40 ℃;
the low-temperature lithium ion battery graphite negative electrode material is prepared by the following steps:
using intercalated graphite as a raw material; preparing intercalation graphite into a solution, and adding a lithium source, an M source, a doping element and a phosphorus source; coating a layer of fast ion conductor on the intercalated graphite by adopting a hydrothermal method or a solvothermal method; then washing, drying and sintering to obtain the low-temperature lithium ion battery graphite cathode material; after adding a lithium source, an M source, a doping element and a phosphorus source, the molar ratio of lithium to M to phosphorus in the system is 1-1.5: 2: 3-4; the M source provides at least one element of Zr, Sc, Ti and Ge with non-zero valence; the doping element is selected from at least one of Si, Al, La, Mg, Zn, Sn, Fe, Mn, Co, Ni, Cu, W, Mo, V and Cr;
preparing the intercalated graphite into a solution, and adding a lithium source, an M source, a doping element and a phosphorus source to obtain an intercalated graphite composite material solution; in the intercalation graphite composite material solution, the molar ratio of lithium, M and phosphorus is 1-1.5: 2: 3-4; the mass ratio of M to graphite in the intercalated graphite is 1-20: 100, respectively; the mol ratio of the doping elements to M is 0-5: 10;
when a layer of fast ion conductor is coated on the intercalated graphite by a hydrothermal method or a solvothermal method, controlling the temperature to be 160-230 ℃ and the time to be 6-48 h;
when a layer of fast ion conductor is coated on the intercalated graphite by a hydrothermal method, a solvent is deionized water or a mixture of water and at least one of absolute ethyl alcohol, ethylene glycol and acetone;
when a layer of fast ion conductor is coated on the intercalated graphite by a solvothermal method, the solvent is selected from at least one of absolute ethyl alcohol, glycol and acetone;
the intercalated graphite is prepared by the following steps:
step one
Adding graphite powder into a ball mill, carrying out wet stirring ball milling, and carrying out spray drying on the mixed solution;
step two
Mixing the graphite powder obtained in the step one with concentrated acid, and then carrying out ultrasonic stirring and centrifugal drying to obtain graphite oxide;
step three
Preparing the graphite oxide obtained in the step two into a solution, adding an intercalation material and a reducing agent, washing and filtering the solution after ultrasonic dispersion, and carrying out heat treatment on a filtered product to obtain an intercalation graphite material;
in the first step, the ball-milling solvent is selected from deionized water or absolute ethyl alcohol; adding a solvent to form a slurry, wherein the mass fraction of graphite in the slurry is 30-70%;
the graphite powder in the first step is one of natural graphite, artificial graphite or mesocarbon microbeads; the grain diameter is 30-100 microns;
in the first step, the ball milling time is 4-24h, and the ball milling speed is 200-400 r/min; when a spray dryer is used, the air inlet temperature is 200-300 ℃ and the air outlet temperature is 100-150 ℃; the granularity of the prepared graphite is 1-20 um;
in the second step, the concentrated acid is one of hydrochloric acid or nitric acid, and the concentration of the concentrated acid is 0.5-3 mol/L; ultrasonically stirring for 3-24 h; the drying temperature is 60-200 ℃;
in the third step, the intercalation substances are aniline, pyrrole or chloride, acetate, sulfate and nitrate of metal tin, cobalt, iron, nickel and manganese; the intercalation is converted into a graphite interlayer conductor in the sintering process;
in the third step, the reducing agent is hydrazine hydrate, D-sodium erythorbate, sodium sulfite, hydroxylamine or sodium borohydride;
performing ultrasonic dispersion for 1-12h in the third step; washing the solution to pH 6-8; the temperature rise rate of the tubular furnace is 1-10 ℃/min, the temperature is 180-; the atmosphere is at least one selected from the group consisting of an argon atmosphere, a nitrogen atmosphere, an argon-hydrogen atmosphere, a carbon dioxide atmosphere, a hydrogen atmosphere, and a nitrogen dioxide atmosphere.
2. The graphite negative electrode material of the low-temperature lithium ion battery as claimed in claim 1, wherein:
when the M source is a titanium source; the titanium source is tetrabutyl titanate or isopropyl titanate;
the phosphorus source is selected from at least one of diammonium hydrogen phosphate, ammonium dihydrogen phosphate and phosphoric acid;
the lithium source is at least one selected from lithium hydroxide, lithium carbonate, lithium acetate and lithium nitrate.
3. The graphite negative electrode material of the low-temperature lithium ion battery as claimed in claim 1, wherein:
during sintering, sintering in a protective atmosphere; the protective atmosphere is selected from one of argon atmosphere, nitrogen atmosphere and vacuum atmosphere; the temperature rise rate is controlled to be 1-10 ℃/min during sintering, the sintering temperature is 600-900 ℃, and the heat preservation time at the sintering temperature is 4-24 h.
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| CN109817983A (en) * | 2019-01-03 | 2019-05-28 | 江西星盈科技有限公司 | Lithium ion battery and its negative electrode tab and negative electrode material and preparation process |
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| CN113422082B (en) * | 2021-07-06 | 2023-04-21 | 中国科学技术大学 | Graphene-like carbon material electrocatalyst containing nitrogen-doped carbon five-membered ring structure, and preparation method and application thereof |
| CN114628659A (en) * | 2022-04-18 | 2022-06-14 | 晖阳(贵州)新能源材料有限公司 | Graphite cathode composite material for power battery and preparation method thereof |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100379062C (en) * | 2002-06-21 | 2008-04-02 | 优米科尔公司 | Carbon-coated Li-containing powders and process for production thereof |
| CN102340006A (en) * | 2011-09-30 | 2012-02-01 | 湖南大学 | Method for improving low-temperature performance of power lithium ion battery at different low-temperature environments |
| CN102646818A (en) * | 2012-04-28 | 2012-08-22 | 中南大学 | Preparation method for composite cathode material of lithium ion battery |
| CN103296277A (en) * | 2012-03-01 | 2013-09-11 | 复旦大学 | Graphite intercalation compound lithium-ion battery negative electrode material, as well as preparation method and application thereof |
| WO2015132845A1 (en) * | 2014-03-03 | 2015-09-11 | 株式会社日立製作所 | All-solid-state battery |
| CN107743645A (en) * | 2015-04-23 | 2018-02-27 | 威廉马歇莱思大学 | Carbon nano pipe array as the vertical alignment of electrode |
| CN107946576A (en) * | 2017-11-21 | 2018-04-20 | 中航锂电（洛阳）有限公司 | A kind of high magnification graphite cathode material and preparation method thereof, lithium ion battery |
Family Cites Families (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101214952A (en) * | 2007-12-31 | 2008-07-09 | 平顶山工学院 | Modified method of natural graphite material for lithium ion battery |
| KR101849976B1 (en) * | 2011-04-08 | 2018-05-31 | 삼성전자주식회사 | Electrode active material, preparing method thereof, electrode including the same, and lithium secondary battery employing the same |
| US8765303B2 (en) * | 2012-04-02 | 2014-07-01 | Nanotek Instruments, Inc. | Lithium-ion cell having a high energy density and high power density |
| CN103904304A (en) * | 2012-12-28 | 2014-07-02 | 惠州比亚迪电池有限公司 | Lithium ion battery negative pole active material and preparation method thereof, and lithium ion battery |
| CN103904305B (en) * | 2012-12-28 | 2016-04-27 | 惠州比亚迪电池有限公司 | Negative active core-shell material of a kind of lithium ion battery and preparation method thereof and a kind of lithium ion battery |
| CN106876707A (en) * | 2017-04-05 | 2017-06-20 | 宁波力赛康新材料科技有限公司 | A kind of solid lithium battery |
| CN107919477B (en) * | 2017-12-22 | 2020-10-09 | 湖南工业大学 | Application of mixed expanded graphite as negative electrode material of lithium ion battery |
-
2018
- 2018-06-22 CN CN201810647061.5A patent/CN108987687B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100379062C (en) * | 2002-06-21 | 2008-04-02 | 优米科尔公司 | Carbon-coated Li-containing powders and process for production thereof |
| CN102340006A (en) * | 2011-09-30 | 2012-02-01 | 湖南大学 | Method for improving low-temperature performance of power lithium ion battery at different low-temperature environments |
| CN103296277A (en) * | 2012-03-01 | 2013-09-11 | 复旦大学 | Graphite intercalation compound lithium-ion battery negative electrode material, as well as preparation method and application thereof |
| CN102646818A (en) * | 2012-04-28 | 2012-08-22 | 中南大学 | Preparation method for composite cathode material of lithium ion battery |
| WO2015132845A1 (en) * | 2014-03-03 | 2015-09-11 | 株式会社日立製作所 | All-solid-state battery |
| CN107743645A (en) * | 2015-04-23 | 2018-02-27 | 威廉马歇莱思大学 | Carbon nano pipe array as the vertical alignment of electrode |
| CN107946576A (en) * | 2017-11-21 | 2018-04-20 | 中航锂电（洛阳）有限公司 | A kind of high magnification graphite cathode material and preparation method thereof, lithium ion battery |
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