Lithium precipitation prevention graphite negative electrode composite material adapting to low-temperature quick charge working condition as well as preparation method and application of lithium precipitation prevention graphite negative electrode composite material

Abstract

The invention relates to the technical field of lithium ion batteries, and discloses a lithium precipitation prevention graphite negative electrode composite material adapting to a low-temperature quick charge working condition and a preparation method and application thereof. The method comprises the following steps: loading indium antimonide on the surfaces of graphite particles, and carrying out pretreatment by adopting an anionic surfactant; and then constructing a nitrogen-containing organic metal framework compound containing cobalt on the surface of the pretreated composite material, and finally performing pyrolysis treatment to obtain the negative electrode composite material. The preparation method comprises the following steps: coating an indium antimonide / graphite with a ZIF derivative to form Namp; the Co-doped porous carbon layer not only improves the conductivity, but also can effectively dredge the electrolyte and strengthen the transport process of Li < + >, so as to prevent lithium precipitation of the graphite negative electrode under the condition of low-temperature fast charge; meanwhile, the Co element is doped with indium antimonide, agglomeration and inactivation of In can be effectively inhibited due to the steric effect, and therefore the cycle performance is further improved; n is doped with indium antimonide, the band gap is reduced, and the free electron concentration is increased, so that the conductivity of the material is improved, and a lithium intercalation energy barrier can be effectively reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of lithium-ion batteries, and particularly to a lithium precipitation prevention graphite anode composite material suitable for low-temperature fast charging conditions, a preparation method thereof, and an application thereof. Background Art

[0002] Due to significant advantages such as high energy density, long cycle life, and large output voltage, lithium-ion batteries have been increasingly widely used in daily production and life. Conventional lithium-ion batteries have severely degraded performance under low-temperature environments and fast charging service conditions due to the slow kinetics of the graphite anode. Most lithium-ion batteries cannot be charged at -20°C or at high room temperature rates (such as 4C). Forced charging will result in severe lithium precipitation on the anode, leading to thermal runaway safety risks. Therefore, improving the charge transfer ability of the anode material and reducing the charge transfer impedance are the keys to optimizing fast charging performance and low-temperature performance.

[0003] The basic problem faced by graphite anode materials during low-temperature charging is that at low temperatures, the diffusion rate of Li + becomes slower, and the charge transfer rate also decreases, resulting in severe degradation of low-temperature performance. In particular, during low-temperature charging, due to the slower movement rate of Li + and the hindrance of charge transfer, a large amount of Li + will directly deposit on the surface of the graphite anode to form dendritic lithium metal crystals, causing the lithium-ion battery to malfunction and even posing serious safety risks. To solve the series of problems existing in the operation of lithium-ion batteries at low temperatures and fast charging, Chinese Patent CN114335462B discloses a graphite anode material for low temperatures. It uses a metal-organic framework material to coat the graphite material, and then forms metal single nanoparticles, such as cobalt nanoparticles and a porous structure, on the graphite surface through heat treatment. On the one hand, the cobalt metal nanoparticles enhance the electronic conductivity of the graphite anode material. On the other hand, the coordination structure of its surface with N elements and the existing forms such as surface oxides have a strong adsorption effect on Li + The combination of the two together improves the kinetics of the Li + charge transfer step. Therefore, to a certain extent, the charge transfer ability of the graphite anode material can be improved. However, due to the agglomeration of cobalt metal nanoparticles during the heat treatment process, the size of the cobalt metal nanoparticles is relatively large, seriously affecting the charge transfer ability of the graphite anode material, and its low-temperature charging problem has not been effectively improved. Therefore, in order to broaden the application of lithium-ion batteries in various scenarios such as alpine regions and fast charging service, further research on improving the charge transport performance of graphite anode materials is still needed. Summary of the Invention

[0004] Based on this, the present invention provides a lithium - precipitation - resistant graphite anode composite material suitable for low - temperature fast - charging conditions, aiming to effectively improve the charge - transfer performance of the graphite anode material to broaden the application of lithium - ion batteries in various scenarios such as alpine regions and fast - charging services. The present invention uses small - particle - size graphite anodes as the core, and coats indium antimonide on its surface to form an indium antimonide / graphite structure. Among them, the lithium - intercalation potential of indium antimonide is high (0.55 - 0.87 V), which can preferentially intercalate lithium, achieving the purpose of effectively preventing lithium precipitation, and its relatively large atomic spacing enables it to charge and discharge quickly under low - temperature conditions. However, during the lithium - intercalation process, In will precipitate and agglomerate. After the In metal grows in agglomerates, the contact area with Sb becomes smaller and it cannot be transformed back into InSb, resulting in poor cycle stability of InSb. Moreover, the poor ionic and electronic conductivity of InSb also limits the lithium - ion insertion and extraction reactions, resulting in poor rate performance. Coating the outside of indium antimonide / graphite with a ZIF - 67 carbonized derivative forms a porous carbon layer doped with N and Co. The porous carbon layer that catalyzes graphitization improves the conductivity of indium antimonide, and its porous characteristics can effectively conduct the electrolyte and strengthen the transport process of Li + The transport process. Further, during the carbonization process, Co elements are doped into indium antimonide. Due to the steric - hindrance effect, the agglomeration and deactivation of In can be effectively inhibited, thereby further improving the cycle performance; N - doping indium antimonide reduces the bandgap and increases the free - electron concentration, thereby improving the conductivity of the material and effectively reducing the lithium - intercalation energy barrier.

[0005] To achieve the above - mentioned purpose, in the first aspect, the present invention provides a preparation method of a lithium - precipitation - resistant graphite anode composite material suitable for low - temperature fast - charging conditions, which includes the following steps:

[0006] S1. Load indium antimonide on the surface of graphite particles to obtain an indium antimonide / graphite composite material;

[0007] S2. Pretreat the indium antimonide / graphite composite material with an anionic surfactant;

[0008] S3. Construct a nitrogen - containing organometallic framework compound containing cobalt on the surface of the pretreated indium antimonide / graphite composite material to obtain an indium antimonide / graphite composite material coated with a nitrogen - containing organometallic framework compound containing cobalt;

[0009] S4. Pyrolyze the indium antimonide / graphite composite material coated with a nitrogen - containing organometallic framework compound containing cobalt to obtain a lithium - precipitation - resistant graphite anode composite material suitable for low - temperature fast - charging conditions.

[0010] As a further preferred technical solution of the present invention, the D50 of the graphite particles is 4 - 15 um, such as 4 um, 6 um, 8 um, 10 um, 12 um, 15 um, etc., and the optimal size is 7 um. Selecting small - particle - size graphite can shorten the Li + diffusion path and enhance the Li+ Transport kinetics; and / or, the mass fraction of indium antimonide in the indium antimonide / graphite composite material is 0.5 to 20%, such as 0.5%, 1.0%, 2.0%, 5%, 10%, 15%, 20%, etc., and the optimal loading amount is 10%. The high lithium intercalation potential of indium antimonide can prevent lithium deposition at low temperatures.

[0011] As a further preferred technical solution of the present invention, in step S1, indium antimonide is loaded on the surface of graphite particles by DC sputtering. Of course, other traditional processes can also be used to load indium antimonide on the surface of graphite particles, which is not limited here.

[0012] The process of loading indium antimonide on the surface of graphite particles by DC sputtering includes:

[0013] Place the graphite particles in a sample container, and use a vacuum pump to pump the pressure in the vacuum chamber to (5 - 10)×10 -4 Pa, and fill Ar into the vacuum chamber at a flow rate of 5 - 10 mL / min to maintain the pressure in the vacuum chamber at (3 - 6)×10 -1 Pa. The InSb target surface is located directly above the sample container, and the DC sputtering power is 25 - 75 W. While the target surface is discharging, the sample container is driven by a stepping motor to swing back and forth, so that the graphite particles roll back and forth in the container. The variable-frequency vibration generator drives the sample container to resonate, and the vibration frequency changes cyclically between 10 - 30 kHz. The sputtering time is 60 - 120 s to obtain the indium antimonide / graphite. Among them, the stepping motor and the variable-frequency vibration generator can be replaced by other devices with the same function, and the DC sputtering power can be adjusted according to actual needs.

[0014] As a further preferred technical solution of the present invention, in step S4, the specific process of constructing a cobalt-containing nitrogen-containing metal-organic framework compound on the surface of the pretreated indium antimonide / graphite composite material includes:

[0015] S4-1. Add the pretreated indium antimonide / graphite composite material into a methanol solution, stir and disperse to obtain a methanol dispersion of the indium antimonide / graphite composite material; dissolve cobalt nitrate in a methanol solution to obtain a methanol solution of cobalt nitrate; dissolve 2-methylimidazole in methanol to obtain a 2-methylimidazole methanol solution; among them, the molar ratio of cobalt nitrate:2-methylimidazole is preferably 1:16.

[0016] S4-2. Slowly pour the methanol solution of cobalt nitrate into the methanol dispersion of the indium antimonide / graphite composite material, and stir for 1 - 24 h; then add the 2-methylimidazole methanol solution dropwise, continue to stir for 4 - 24 h, perform suction filtration, and wash with methanol 1 - 3 times. After drying, ZIF-67 is coated on the surface of the indium antimonide / graphite composite material to obtain the indium antimonide / graphite@ZIF-67 composite material;

[0017] S4-3. Pyrolyze the indium antimonide / graphite@ZIF-67 composite material at 600-1000 °C to obtain a low-temperature fast-charging graphite anode material.

[0018] As a further preferred technical solution of the present invention, the anionic surfactant is one or more of sodium polystyrene sulfonate, sodium dodecyl sulfonate, and sodium dodecyl benzene sulfonate. Among them, sodium polystyrene sulfonate (PSS) is the most preferred. Using PSS as the anionic surfactant to activate graphite particles makes the graphite surface negatively charged, which helps Co 2+ to be evenly adsorbed on the surface of graphite particles. After adding 2-methylimidazole, it can be anchored on the surface of indium antimonide / graphite particles to uniformly form a precursor of a coating layer such as ZIF-67.

[0019] Furthermore, the mass ratio of PSS to the indium antimonide / graphite composite material is 1:0.5 to 1:2. Among them, if the dosage of PSS is too small, the activation of the graphite particle surface is incomplete, resulting in Co 2+ not being completely adsorbed on the graphite surface, and ZIF-67 will be formed in the solution; if the dosage of PSS is too large, the material waste is relatively serious.

[0020] Furthermore, in step S4, the proportional relationship between the cobalt metal ions and the graphite dosage is: 0.25-1 mmol of cobalt metal ions are added to 1 g of indium antimonide / graphite composite material, and the molar ratio of cobalt metal ions to 2-methylimidazole is 1:4 to 1:32. Among them, this dosage and ratio can control the thickness of the coating layer, thereby ensuring that the initial efficiency of the composite anode sample is maintained between 87% and 92%. It is preferred to control the coating layer thickness within 50-500 nm. If the coating layer thickness is too small, the porous characteristics cannot be achieved, and it is difficult for the Co metal nanoparticles formed by pyrolysis to form a graphitized carbon layer coating, resulting in a risk of dissolution in the electrolyte; if the coating layer thickness is too large, the specific surface area is too large, leading to a serious reduction in the initial efficiency.

[0021] In the present invention, both the indium antimonide and the ZIF pyrolysis material are nanoscale.

[0022] According to the second aspect of the present invention, the present invention also provides an anti-lithium precipitation graphite anode composite material suitable for low-temperature fast-charging conditions, which is prepared by the method of the first aspect and has a porous structure on its surface.

[0023] According to the third aspect of the present invention, the present invention also provides an application of the anti-lithium precipitation graphite anode composite material suitable for low-temperature fast-charging conditions in the second aspect as an anode material (also known as an active material) in a lithium-ion battery.

[0024] Compared with the prior art, the present invention can achieve the following beneficial effects:

[0025] 1) The present invention uses small particle size graphite negative electrode as the core, and indium antimonide is coated on its surface to form an indium antimonide / graphite structure. The zinc blende structure of indium antimonide has a relatively high lithium insertion / extraction potential (0.55 - 0.87V), which can preferentially insert lithium into the graphite, restricting the growth of a large number of lithium dendrites on the electrode surface. The unique reaction process of indium antimonide during lithium storage results in a theoretical volume change of only 1.5%, and its relatively large atomic spacing enables it to charge and discharge rapidly under low-temperature conditions. However, its poor ionic and electronic conductivity limits the insertion and extraction reactions of lithium ions, as well as its rate performance. Moreover, during the lithium insertion process, In will precipitate and agglomerate. After the agglomerated In metal grows, the contact area with Sb becomes smaller, and it cannot transform back to InSb, resulting in poor cycle stability of InSb. Coating the outside of indium antimonide / graphite with ZIF derivatives forms a porous carbon layer doped with N and Co, which not only improves the conductivity but also effectively channels the electrolyte and strengthens the transport process of Li + ions. Meanwhile, due to the steric hindrance effect, Co doping of indium antimonide can effectively inhibit the agglomeration inactivation of In, thereby further improving the cycle performance; N doping of indium antimonide reduces the band gap and increases the free electron concentration, thereby improving the conductivity of the material and effectively reducing the lithium insertion energy barrier. This preparation method is reasonably designed and simple to operate.

[0026] 2) The present invention uses a nitrogen-containing organometallic framework compound containing cobalt (such as ZIF-67) as the precursor of the coating layer. After heat treatment, a porous carbon coating layer can be formed. Its porous characteristics can significantly improve the electrolyte infiltration and liquid retention performance, facilitating the transport process of Li + ions and effectively improving the low-temperature charging performance. The Co metal nanoparticles wrapped by the graphitized carbon layer formed during pyrolysis significantly improve the conductivity, thus contributing to accelerating the charge transfer process under low-temperature conditions.

[0027] 3) The present invention uses a nitrogen-containing organometallic framework compound containing cobalt (such as ZIF-67) as the precursor of the coating layer. After heat treatment, N elements can effectively dope indium antimonide during the pyrolysis process, reducing the energy band and lithium insertion energy barrier of indium antimonide, and significantly improving the electronic and ionic conductivity; Co doping of indium antimonide, due to the steric hindrance effect, can effectively inhibit the agglomeration inactivation of In, thereby further improving the cycle performance.

[0028] 4) The present invention selects small particle size graphite as the core, and the small particle size graphite significantly shortens the diffusion path of Li + ions, improving the low-temperature charging performance to a certain extent. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The present invention will be further described in detail below in conjunction with the drawings and specific embodiments.

[0030] Figure 1 The lithium-ion half-cells assembled in Example 1 of the present invention and Comparative Examples 1-4 have a lithium intercalation curve at 0 °C and 0.1 C (1 C = 372 mAh / g).

[0031] Figure 2 The lithium-ion half-cells assembled in Example 1 of the present invention and Comparative Examples 1 and 3 have a cycling curve at 25 °C and 1 C (1 C = 372 mAh / g).

[0032] Figure 3 The charging curve at -30 °C of the 5 Ah lithium iron phosphate (LFP) || graphite soft-pack battery assembled in Example 1 and Comparative Example 4.

[0033] The realization of the object, functional features and advantages of the present invention will be further described with reference to the embodiments and the accompanying drawings. Detailed Description of the Invention

[0034] The following further details the specific embodiments of the present invention with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustrative and explanatory purposes only and are not intended to limit the present invention.

[0035] Unless otherwise defined, the technical terms used in the following embodiments have the same meanings as commonly understood by those skilled in the art to which the present invention pertains. The test reagents used in the following embodiments are all conventional biochemical reagents unless otherwise specified; the experimental methods are all conventional methods unless otherwise specified.

[0036] Example 1 (InSb + graphite + ZIFs coating treatment):

[0037] S1. Load InSb on the surface of graphite material to obtain indium antimonide / graphite composite material, specifically:

[0038] Place graphite particles with a D50 of 7 μm in a sample container, and use a vacuum pump to pump the pressure in the vacuum chamber to 8×10 - 4 Pa, and fill the vacuum chamber with high-purity Ar at a flow rate of 10 mL / min to maintain the pressure in the vacuum chamber at 6×10 -1 Pa. Place the InSb target surface directly above the sample container, and set the DC sputtering power to 50 W. The charging container is vibrated in a tray vibration mode, and the movement mode of the material is vibration. While the target surface is glowing, the sample container is driven by a stepping motor to make reciprocating swings, so that the graphite particles roll back and forth in the container. At the same time, the sample container is driven by a variable-frequency vibration generator to resonate, and the vibration frequency changes cyclically between 30 kHz. The sputtering time is 120 s to obtain indium antimonide / graphite composite material, and the mass fraction of InSb in the sputtering layer on the graphite surface is controlled to 10%.

[0039] S2. Weigh 5 g of sodium polystyrene sulfonate (PSS) and 18 g of sodium chloride (NaCl), dissolve them in 300 mL of deionized water to obtain an aqueous salt solution of sodium polystyrene sulfonate. Add the indium antimonide / graphite composite material obtained in S1 to the aqueous salt solution of sodium polystyrene sulfonate, stir for 6 - 8 h to obtain a dispersion of indium antimonide / graphite composite material. After suction filtration, add it to 300 mL of methanol solution, stir and disperse to obtain a methanol dispersion of indium antimonide / graphite composite material.

[0040] S3. Weigh 2.5 mmol of cobalt nitrate and dissolve it in 100 mL of methanol solution to obtain a methanol solution of cobalt nitrate. According to the molar ratio of cobalt nitrate to 2 - methylimidazole being 1:16, weigh 2 - methylimidazole and dissolve it in methanol to obtain a methanol solution of 2 - methylimidazole.

[0041] S4. Slowly pour the methanol solution of cobalt nitrate into the above - mentioned methanol dispersion of indium antimonide / graphite composite material, and continue to stir for 12 h. Then, slowly add the methanol solution of 2 - methylimidazole drop by drop, continue to stir for 12 h, perform suction filtration, wash with methanol 3 times, and after drying, a ZIF - 67 is coated on the surface of the indium antimonide / graphite composite material.

[0042] S5. Pyrolyze the product of S4 in an argon atmosphere, with a pyrolysis temperature of 750 °C, a heating rate of 10 °C / min, and a holding time of 4 h. After grinding, the lithium - precipitation - proof graphite negative electrode composite material is obtained, denoted as indium antimonide / graphite@ZIF - 67 negative electrode composite material.

[0043] Perform electrochemical performance tests on the lithium - precipitation - proof graphite negative electrode composite material of Example 1 when applied to a lithium - ion half - cell, specifically as follows:

[0044] Use a graphite electrode as the working electrode (where the mass ratio of the active material (indium antimonide / graphite@ZIF - 67 negative electrode composite material), the conductive agent (acetylene black), and the binder (polyvinylidene fluoride) is 8:1:1), a lithium sheet as the counter electrode, add 50 μL of electrolyte (1.0 M LiPF6 dissolved in ethylene carbonate (EC) / ethyl methyl carbonate (EMC) / dimethyl carbonate (DMC) / ethyl acetate (EA) / ethyl propionate (EP) (20 / 20 / 30 / 5 / 25, volume ratio) + 0.8 wt% vinylene carbonate (VC) + 1 wt% fluoroethylene carbonate (FEC)), and use Celgard 2500 as the separator to assemble a 2032 - type coin cell. The test conditions are constant - current charge - discharge, and the voltage range is 0.01 V - 2 V.

[0045] Comparative Example 1 (InSb + graphite):

[0046] Prepare an indium antimonide / graphite composite material using the S1 step of Example 1, and then assemble a lithium - ion half - cell and perform electrochemical performance tests under the same method and conditions as above.

[0047] Comparative Example 2 (ZIFs + graphite):

[0048] It is obtained by directly loading ZIFs on graphite material and then undergoing pyrolysis treatment. The difference between its preparation method and that of Example 1 is that: compared with Example 1, the S1 step is omitted, and the S2 - S5 steps of Example 1 are used to prepare the ZIF-coated graphite anode composite material, and then a lithium-ion half-cell is assembled and its electrochemical performance is tested by the same method and conditions as above.

[0049] Comparative Example 3 (InSb + graphite + C coating treatment):

[0050] First, indium antimonide / graphite composite material is prepared and then carbon is coated. Compared with Example 1, the S1 step of Example 1 is used to prepare the indium antimonide / graphite composite material, then glucose is dissolved in deionized water to form a 25 wt% glucose aqueous solution, the indium antimonide / graphite composite material is added to the glucose aqueous solution, and a uniform graphite suspension is formed by ultrasonic treatment. Stirring is continued for 12 h, filtration is carried out, and it is washed 3 times with deionized water. After drying, glucose is coated on the surface of the indium antimonide / graphite composite material. Finally, the S5 step of Example 1 is repeated to obtain the negative electrode composite material of InSb + graphite + C coating treatment, and then a lithium-ion half-cell is assembled and its electrochemical performance is tested by the same method and conditions as above.

[0051] Comparative Example 4 (raw graphite):

[0052] The untreated raw graphite in Example 1 is used as the active material, and then a lithium-ion half-cell is assembled and its electrochemical performance is tested by the same method and conditions as above.

[0053] The half-cells assembled in the above examples and comparative examples are cycled at a current density of 0.1C for 5 cycles at room temperature to form a stable solid electrolyte interface layer (SEI), and then low-temperature and fast-charging tests are carried out.

[0054] Low-temperature test: The pre-cycled battery is placed at 0 °C and discharged to 0.1 V at 0.1C, and its low-temperature lithium intercalation capacity is tested. The results are as Figure 1 and Table 1.

[0055] Table 1

[0056]

[0057]

[0058] As can be seen from the half-cell test results in Table 1, the half-cell using the negative electrode composite material treated with InSb + graphite + ZIFs coating of the present invention has excellent low-temperature lithium intercalation ability, has a higher lithium intercalation capacity (350 mAh / g) at 0 °C, shows a higher lithium intercalation potential, and is significantly superior to each comparative example, indicating that it can effectively prevent the precipitation of lithium metal at low temperatures.

[0059] Fast charge test: The pre-cycled battery was cycled at a current density of 1C for 1000 cycles at room temperature (25 °C), and the results are as Figure 2 , and it can be seen that the negative electrode composite material treated with InSb + graphite + ZIFs coating of the present invention shows the highest capacity retention rate (88.17%), which is much higher than the materials treated with InSb + graphite + C coating (83.52%) and the materials of InSb + graphite (82.76%).

[0060] The lithium precipitation prevention graphite negative electrode composite material of Example 1 and the original graphite of Comparative Example 4 were respectively used as active materials to conduct low-temperature charging electrochemical performance tests on lithium-ion soft-pack full batteries, as follows:

[0061] Using a graphite electrode as the negative electrode (where the mass ratio of the active material, conductive agent (acetylene black), and binder (sodium carboxymethyl cellulose and styrene-butadiene rubber) is 96:1:3), the positive electrode is lithium iron phosphate (LFP, the mass ratio of the conductive agent Super P and the binder polyvinylidene fluoride is 95:2:3), the separator uses a Celgard 2500 separator, and a 5Ah soft-pack battery is assembled using the same electrolyte as the above half-cell test. After the battery was activated at 0.1C for 3 cycles at room temperature, it was placed at -30 °C and charged at 0.1C (1C = 1.58 mAcm -2 ) to 3.65V, and then charged at a constant voltage of 3.65V until the current ≤ 0.05C was cut off, and its low-temperature charging capacity was tested. The results are as Figure 3 shown: The battery assembled with Example 4 of the present invention has a rechargeable capacity of 4.12Ah at -30 °C, maintaining 82.4% of the room temperature capacity. Among them, the capacity in the constant current charging stage is 2.35Ah, and the capacity in the constant voltage charging stage is 1.77Ah. While the battery using the unmodified original graphite of Comparative Example 4 has a rechargeable capacity of only 3.45Ah at -30 °C, maintaining 69% of the room temperature capacity. Among them, the capacity in the constant current charging stage is 1.45Ah, and the capacity in the constant voltage charging stage is 2Ah. The low-temperature charging capacity of the battery assembled with Comparative Example 4 is much lower than that of the battery assembled with Example 1, and its charging voltage platform is higher, indicating that the battery polarization is greater and the possibility of lithium precipitation is higher. In summary, the modified graphite negative electrode material of the present invention has a higher capacity during low-temperature environment charging, has a certain inhibition on the occurrence of lithium precipitation, and shows higher safety.

[0062] Although the specific embodiments of the present invention have been described above, those skilled in the art should understand that these are only illustrative examples, and various changes or modifications can be made to these embodiments without departing from the principles and essence of the present invention. The protection scope of the present invention is only defined by the appended claims.

Claims

1. A method for preparing a lithium-preventing graphite negative electrode composite material suitable for low-temperature fast charging conditions, characterized in that: The following steps are involved: S1, loading indium antimonide on the surface of graphite particles to obtain an indium antimonide / graphite composite material; S2, pretreating the indium antimonide / graphite composite material with an anionic surfactant; S3, constructing a nitrogen-containing organic metal framework compound containing cobalt on the surface of the pretreated indium antimonide / graphite composite material to obtain an indium antimonide / graphite composite material coated with a nitrogen-containing organic metal framework compound; S4. The indium antimonide / graphite composite material of the nitrogen-containing organic metal framework compound coated with cobalt is subjected to pyrolysis treatment to obtain a lithium-elution-resistant graphite negative electrode composite material suitable for low-temperature fast charging conditions.

2. The method for preparing a lithium-preventing graphite negative electrode composite material adapted to low-temperature fast charging conditions according to claim 1, characterized in that: The D50 of the graphite particles is 4-15 um; and / or the mass fraction of indium antimonide in the indium antimonide / graphite composite material is 0.5-20%.

3. The method for preparing a lithium-preventing graphite negative electrode composite material adapted to low-temperature fast charging conditions according to claim 2, characterized in that: In step S1, indium antimonide is loaded on the surface of graphite particles by direct current sputtering.

4. The method for preparing the anti-lithium-evolution graphite negative electrode composite material adapted to low-temperature fast charging conditions according to claim 3, characterized in that: The DC sputtering process includes: Graphite particles are placed in a sample container, with the indium antimonide target surface located directly above the sample container. While the target surface is glowing, the sample container is controlled to swing back and forth so that the graphite particles roll back and forth in the container. At the same time, the sample container is controlled to resonate, and the vibration frequency changes cyclically between 10 and 30 kHz.

5. The method for preparing the anti-lithium-evolution graphite negative electrode composite material adapted to low-temperature fast charging conditions according to claim 4, characterized in that: The sample container is driven by a stepping motor to swing back and forth, and the sample container is driven by a variable frequency vibration generator to generate resonance.

6. The method for preparing the anti-lithium-evolution graphite negative electrode composite material adapted to low-temperature fast charging conditions according to claim 1, characterized in that: The anionic surfactant is one or more of sodium polystyrene sulfonate, sodium dodecyl sulfonate and sodium dodecylbenzene sulfonate.

7. The method for preparing the anti-lithium-evolution graphite negative electrode composite material adapted to low-temperature fast-charging conditions according to claim 1, characterized in that: The temperature of the pyrolysis treatment is 600-1000°C.

8. The method for preparing the anti-lithium-evolution graphite negative electrode composite material adapted to low-temperature fast-charging conditions according to claim 1, characterized in that: The nitrogen-containing organic metal framework compound containing cobalt is ZIF-67.

9. A lithium-prevention graphite negative electrode composite material suitable for low-temperature fast charging conditions, characterized in that: The method is prepared by any one of claims 1 to 8.

10. Use of the anti-lithium-evolution graphite negative electrode composite material adapted to low-temperature fast-charging conditions as claimed in claim 9 as a negative electrode material in a lithium-ion battery.

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