Evaluation method for fast charging performance of ternary positive electrode material

Abstract

The invention relates to a method for evaluating the fast charging performance of a ternary positive electrode material, the ternary positive electrode material contains Co, and the evaluation method comprises the following steps: detecting the mass concentration of LiOH and the mass concentration of Li2CO3 in the ternary positive electrode material, the specific surface area and the molar weight of Co contained in each mole of the ternary positive electrode material; detecting the particle size of primary particles of the ternary positive electrode material and the corresponding particle size when the cumulative particle size distribution percentage reaches 50%; testing the resistivity of the ternary positive electrode material in a powder state; and calculating a fast charge factor kf, and judging whether the ternary positive electrode material is the fast charge type positive electrode material or not according to the fast charge factor kf obtained through calculation and an evaluation standard. According to the evaluation method of the fast charge factor, provided by the invention, the fast charge performance of the ternary positive electrode material can be evaluated, and the DCR value of the material can be effectively evaluated, so that performance evaluation support is provided for design such as modification of the material.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to the technical field of lithium ion batteries, in particular to an evaluation method for fast charging performance of a ternary positive electrode material. BACKGROUND

[0002] At present, the electric vehicle industry is developing rapidly, and the demand for power batteries has increased significantly. As one of the four main materials of power batteries, positive electrode materials play a key role in electrical performance. Electric vehicles are developing towards long endurance and high safety, so improving energy density, prolonging service life and improving material safety and stability are urgent problems to be solved for positive electrode materials. Among them, the hexagonal system layered high-nickel ternary positive electrode material LiNi x Co y Mn z O2 has attracted widespread attention due to its high energy density.

[0003] In addition, with the development of society and technology, the rapid charging capability of lithium ion batteries has become an important parameter index of electric vehicles. The working performance of lithium ion batteries mainly depends on the selection and matching of positive and negative electrode material systems. Only by selecting positive and negative electrode materials that can be quickly charged can lithium ion batteries with fast charging capability be achieved. Therefore, how to accurately evaluate the fast charging capability of electrode materials is an urgent problem to be solved in the process of material research, production and sales.

[0004] At present, the method for evaluating the fast charging capability of electrode materials mainly compares the charging capacity at different charging rates. However, there are many factors affecting this evaluation method, including electrode materials, electrolyte and separator, etc., which cannot accurately reflect the fast charging performance of electrode materials.

[0005] For layered high-nickel ternary positive electrode materials, due to the different composition and structure of the materials themselves, and possibly including various modifications, it is impossible to form a unified evaluation method for the fast charging performance of layered high-nickel ternary positive electrode materials. SUMMARY

[0006] In order to solve the above technical problems, the present disclosure provides an evaluation method for fast charging performance of a ternary positive electrode material.

[0007] In a first aspect, the present disclosure provides an evaluation method for fast charging performance of a ternary positive electrode material, the ternary positive electrode material containing Co, the evaluation method comprising:

[0008] S1. Detecting the mass concentration m(LiOH) of LiOH and the mass concentration m(Li2CO3) of Li2CO3 in the ternary positive electrode material, in ppm; detecting the specific surface area β of the ternary positive electrode material, in m 2 / g; detecting the molar amount c of Co contained in each mole of the ternary positive electrode material, in units of mol; detecting the particle size d of the primary particles of the ternary positive electrode material and the particle size D corresponding to the cumulative particle size distribution percentage of 50% 50 , both in units of μm; testing the resistivity R of the ternary positive electrode material in a powder state, in units of Ω·cm;

[0009] S2. Calculating the ratio a of m(LiOH) and m(Li2CO3), and calculating the product D of D 50 and d, wherein:

[0010] a = m(LiOH) / m(Li2CO3); D = D 50 × d;

[0011] S3. Calculating the fast charging factor k f of the ternary positive electrode material, and the formula is shown in formula I;

[0012]

[0013] S4. According to the calculated fast charging factor k f and the evaluation standard, judging whether the ternary positive electrode material is a fast charging positive electrode material, wherein the evaluation standard includes: when k f ≥ 0.9, the ternary positive electrode material is a fast charging positive electrode material.

[0014] In the prior art, the fast charging evaluation method usually needs to introduce multiple dimensional parameters, for example, the positive and negative active materials, the electrolyte and even the separator also need to be considered, and whether the positive and negative materials are modified or have a coating layer also needs to be considered. However, the fast charging performance evaluation method provided by the present disclosure only starts from the parameters corresponding to the positive electrode material itself, and can evaluate whether the ternary positive electrode material has fast charging performance, which can fully reflect the charging performance of the positive electrode material and provide a reference for the application of the positive electrode material. At the same time, the fast charging performance evaluation method provided by the present disclosure can also compare the modification effect of the positive electrode material on the charging performance.

[0015] Since the ternary positive electrode material has multiple different forms, it can be in a powder state, a compacted state, or a state of being prepared into a positive active material layer. The evaluation method provided by the present disclosure is used to evaluate the charging performance of the ternary positive electrode material itself, and therefore, the resistivity involved in the evaluation method provided by the present disclosure is the resistivity of the ternary positive electrode material in a powder state. The ternary positive electrode material in a powder state is generally in the most original state of the synthesized material, and does not need any post-treatment to realize the evaluation of its charging performance by testing its parameters.

[0016] As a preferred technical solution of the present disclosure, in step S1, m(LiOH) and m(Li2CO3) are obtained by using the test method of potentiometric titration.

[0017] As a preferred technical solution of the present disclosure, in step S1, β is obtained by using the test method of BET.

[0018] As a preferred technical solution of the present disclosure, in step S1, D 50 Both d are calculated by Debye-Scherrer formula.

[0019] As a preferred technical solution of the present disclosure, the molecular formula of the ternary cathode material is Li x Ni y Co z Mn t M m O2, M is selected from at least one of Al, Zr, Y, Sr, W, Ti, Sb, Ce, Mg, Co, Mo or V, wherein:

[0020] x, y, z, t, m represent the molar mass of each molecule in 1 mol of the ternary cathode material, mol, y+z+t+m=1, 1

[0021] As a preferred technical solution of the present disclosure, the molecular formula of the ternary cathode material is Li x Ni y Co z Mn t W m O2, wherein:

[0022] x, y, z, t, m represent the molar mass of each molecule in 1 mol of the ternary cathode material, mol, y+z+t+m=1, 0.8

[0023] In a second aspect, the present disclosure provides an application of the evaluation method of the first aspect in the fast charging performance evaluation of lithium ion batteries.

[0024] In a third aspect, the present disclosure provides a ternary cathode material fast charging performance evaluation device, comprising:

[0025] The detection unit is configured to detect the mass concentration of LiOH, the mass concentration of Li2CO3, the specific surface area, the molar mass of Co contained in each mole of the ternary cathode material, the particle size of primary particles, the particle size corresponding to the cumulative particle size distribution percentage of 50%, and the resistivity of the ternary cathode material in a powder state.

[0026] a calculation unit configured to calculate the data detected by the detection unit and output a fast charging factor k f ;

[0027] an evaluation unit configured to evaluate whether the ternary positive electrode material is a fast charging positive electrode material by the fast charging factor k f

[0028] In a fourth aspect, the present disclosure provides an electronic device, comprising a memory, a processor and a computer program, wherein:

[0029] The computer program is stored in the memory and is configured to be executed by the processor to implement the evaluation method according to the first aspect.

[0030] In a fifth aspect, the present disclosure provides a computer readable storage medium storing a computer program, which, when executed by a processor, implements the evaluation method according to the first aspect.

[0031] The technical solution provided by the embodiments of the present disclosure has the following advantages compared with the prior art:

[0032] (1) The fast charging performance evaluation method provided by the present disclosure can evaluate whether the ternary positive electrode material has fast charging performance only from the parameters corresponding to the positive electrode material itself, which can fully reflect the charging performance of the positive electrode material and provide a reference for the application of the positive electrode material.

[0033] (2) The fast charging performance evaluation method provided by the present disclosure can evaluate the charging performance of the ternary positive electrode material before and after modification, which can provide performance evaluation support for the modification of the ternary positive electrode material.

[0034] (3) The evaluation result of the ternary positive electrode material evaluation method provided by the present disclosure can reflect the DCR performance of the ternary positive electrode material, which further provides support for the performance evaluation of the material. DETAILED DESCRIPTION

[0035] In order to more clearly understand the above-mentioned purposes, features and advantages of the present disclosure, the solutions of the present disclosure will be further described below. It should be noted that the embodiments of the present disclosure and the features in the embodiments can be combined with each other without conflict.

[0036] In the following description, many specific details are set forth in order to provide a thorough understanding of the present disclosure, but the present disclosure can also be implemented in other ways different from those described herein; obviously, the embodiments in the specification are only some embodiments of the present disclosure, not all embodiments.

[0037] ​The evaluation method of the prior art for the fast charging performance needs to introduce multi-dimensional parameters, not only including the parameters of the material itself, but also the parameters related to the application environment, etc. Therefore, the present disclosure provides a method for evaluating whether the ternary positive electrode material has fast charging performance only from the material itself.

[0038] In a first aspect, the present disclosure provides an evaluation method for the fast charging performance of a ternary positive electrode material containing Co, which comprises:

[0039] S1. Detecting the mass concentration m(LiOH) of LiOH and the mass concentration m(Li2CO3) of Li2CO3 in the ternary positive electrode material, in ppm; detecting the specific surface area β of the ternary positive electrode material, in m 2 / g; detecting the molar amount c of Co contained in each mole of the ternary positive electrode material, in mol; detecting the particle size d of the primary particles of the ternary positive electrode material and the particle size D corresponding to the cumulative particle size distribution percentage of 50%, both in μm; and testing the resistivity R of the ternary positive electrode material in the powder state, in Ω·cm; 50

[0040] S2. Calculating the ratio α of m(LiOH) and m(Li2CO3), and calculating the product D of D 50 and d, wherein:

[0041] α = m(LiOH) / m(Li2CO3); D = D 50 × d;

[0042] S3. Calculating the fast charging factor k f of the ternary positive electrode material, and the calculation formula is shown in formula I;

[0043]

[0044] S4. According to the calculated fast charging factor k f and the evaluation standard, judging whether the ternary positive electrode material is a fast charging type positive electrode material, wherein the evaluation standard comprises: when k f ≥ 0.9, the ternary positive electrode material is a fast charging type positive electrode material.

[0045] ​In the prior art, the fast charging evaluation method usually needs to introduce multiple dimensional parameters, for example, the positive and negative active materials, electrolyte and separator also need to be considered, and whether the positive and negative materials are modified or have a coating layer also needs to be considered. The fast charging performance evaluation method provided by the present disclosure only starts from the parameters corresponding to the positive material itself, and can evaluate whether the ternary positive material has fast charging performance, fully reflects the charging performance of the positive material, and provides a reference for the application of the positive material. At the same time, the fast charging performance evaluation method provided by the present disclosure can also compare the modification effect of the positive material on the charging performance.

[0046] Since the ternary positive material has multiple different forms, it can be in a powder state, a compacted state, or a state of being prepared into a positive active material layer. The evaluation method provided by the present disclosure evaluates the charging performance of the ternary positive material itself, and therefore, the resistivity involved in the evaluation method provided by the present disclosure is the resistivity of the ternary positive material in a powder state. The ternary positive material in a powder state is generally in the most original state of the material after synthesis, and does not need any post-treatment to realize the evaluation of its charging performance by testing its parameters.

[0047] As a preferred technical solution of the present disclosure, in step S1, m(LiOH) and m(Li2CO3) are obtained by the potentiometric titration test method.

[0048] In the present disclosure, the mass concentration of LiOH and the mass concentration of Li2CO3 can be obtained simultaneously by the potentiometric titration method.

[0049] As a preferred technical solution of the present disclosure, in step S1, β is obtained by the BET test method.

[0050] As a preferred technical solution of the present disclosure, in step S1, D 50 Both d and D are calculated by the Debye-Scherrer formula.

[0051] As a preferred technical solution of the present disclosure, the molecular formula of the ternary positive material is Li x Ni y Co z Mn t M m O2, M is selected from at least one of Al, Zr, Y, Sr, W, Ti, Sb, Ce, Mg, Co, Mo or V, wherein:

[0052] x, y, z, t, m represent the molar mass of each molecule of the ternary positive material, mol, y+z+t+m=1, 1

[0053] The x can be 1.01, 1.02, 1.03, 1.04, 1.05, 1.06, 1.07, 1.08, 1.09, etc., the y can be 0, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, etc., the z can be 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1, etc., the t can be 0, 0.1, 0.2, 0.3, 0.4, 0.5, etc., and m can be 0.01, 0.02, 0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09, 0.1, etc.

[0054] The evaluation method of the fast charging performance provided by the present disclosure can be applied to all ternary positive electrode materials at present. As long as the ternary positive electrode material meets the definition in the above formula, it can be applied to the fast charging performance evaluation method provided by the present disclosure to evaluate the charging performance, and the evaluation accuracy is high.

[0055] As a preferred technical solution of the present disclosure, the molecular formula of the ternary positive electrode material is Li x Ni y Co z Mn t W m O2, wherein:

[0056] x, y, z, t, m represent the molar mass of each molecule in 1 mol of the ternary positive electrode material, mol, y+z+t+m=1, 0.8

[0057] When the ternary positive electrode material contains Mn element in the structural formula and y, z, t, m are within the above defined range, the evaluation method of the fast charging performance provided by the present disclosure can accurately evaluate whether the ternary positive electrode material has the fast charging performance, and at the same time, the DCR (direct current resistance) performance of the ternary positive electrode material can be effectively reflected through the evaluation result; the modification of the ternary positive electrode material can also be supported by evaluating the charging performance of the ternary positive electrode material before and after modification.

[0058] As a specific embodiment of the present disclosure, the evaluation method is as follows:

[0059] S1: The m(LiOH) and m(Li2CO3) values in the ternary positive electrode material are obtained by using the test method of potential titration, unit: ppm, and the ratio of m(LiOH) to m(Li2CO3) is calculated, denoted as a;

[0060] S2: The specific surface area of the ternary positive electrode material is obtained by using the test method of BET, denoted as β, unit: m2 / g;

[0061] S3: detecting the particle size distribution of the ternary positive electrode material, obtaining D 50 , unit: μm and d, unit: μm by Debye-Scherrer formula, and calculating the value of D 50 ×d, denoted as D, unit: μm 2 ;

[0062] S4: testing the resistivity of the ternary positive electrode material in powder state, denoted as R, unit: Ω·cm;

[0063] S5: calculating the fast charging factor k f by formula I

[0064]

[0065] S6: judging whether the ternary positive electrode material is a fast charging positive electrode material according to the calculated fast charging factor k f and the evaluation standard, wherein the evaluation standard comprises: when k f ≥0.9, the ternary positive electrode material is a fast charging positive electrode material.

[0066] The above-provided fast charging performance evaluation method is verified by providing several different ternary positive electrode materials as follows:

[0067] In the following provided preparation examples, preparation examples 1 and 6 are two different ternary positive electrode materials respectively, and the ternary positive electrode materials obtained from preparation examples 2-4 have the same structural formula as preparation example 1, but due to the difference in raw materials and method parameters, the charging performance of the ternary positive electrode material will also be affected to a certain extent. The 50% SOC DCR of the battery prepared by the ternary positive electrode material of preparation examples 1-6 is tested to verify the fast charging performance evaluation method provided by the present disclosure, and the results are as follows:

[0068] Preparation example 1

[0069] The present preparation example provides a ternary positive electrode material Li 1.05 Ni 0.895 Co 0.05 Mn 0.05 W 0.005 O2 and a preparation method thereof, as follows:

[0070] (1) polycrystalline hydroxide precursor Ni 50 Co 0.90 Mn 0.05 W 0.05(OH)2 was mixed with lithium hydroxide in a molar ratio of 1:1.05, and 0.5 mol% of WO3 was added; sintering was performed under a pure oxygen atmosphere at a temperature of 750°C for 8 hours, and after cooling, the material was broken up and sieved to obtain polycrystalline primary material Li 1.05 Ni 0.895 Co 0.05 Mn 0.05 W 0.005 O2.

[0071] (2) The primary material and pure water were mixed in a mass ratio of 2:1, stirred at 300 rpm for 3 min, and then suction filtered; the filter cake was dried in a vacuum oven at 150°C for 4 h to obtain the water-washed material;

[0072] (3) The water-washed material was added with 1000 ppm boric acid, sintering was performed under a pure oxygen atmosphere at a temperature of 400°C for 6 h, and after cooling, the material was broken up to obtain polycrystalline Li 1.05 Ni 0.895 Co 0.05 Mn 0.05 W 0.005 O2 cathode material.

[0073] Preparation Example 2

[0074] The present preparation example provides a ternary cathode material Li 1.05 Ni 0.88 Co 0.09 Mn 0.03 W 0.005 O2 and a preparation method thereof.

[0075] The difference from Preparation Example 1 is that in the present preparation example, the precursor is replaced by Ni 0.88 Co 0.09 Mn 0.03 (OH)2.

[0076] Preparation Example 3

[0077] The present preparation example provides a ternary cathode material Li 1.05 Ni 0.895 Co 0.05 Mn 0.05 W 0.005 O2 and a preparation method thereof.

[0078] The difference from Preparation Example 1 is that in the present preparation example, step (2) is not performed.

[0079] Preparation Example 4

[0080] The present preparation example provides a ternary cathode material Li 1.05 Ni 0.895 Co 0.05 Mn 0.05 W0.005 O2 and a method for preparing the same

[0081] The difference from Preparation Example 1 is that, in the present preparation example, the sintering temperature of step (1) is 800℃.

[0082] Preparation Example 5

[0083] The present preparation example provides a ternary positive electrode material Li 1.05 Ni 0.895 Co 0.05 Mn 0.05 W 0.005 O2 and a method for preparing the same

[0084] The difference from Preparation Example 1 is that, in the present preparation example, the precursor D 50 = 18 μm.

[0085] Preparation Example 6

[0086] The present preparation example provides a ternary positive electrode material Li 1.05 Ni 0.885 Co 0.06 Mn 0.05 W 0.005 O2 and a method for preparing the same.

[0087] (1) D 50 = 10 μm polycrystalline hydroxide precursor Ni 0.90 Co 0.05 Mn 0.05 (OH)2 is mixed with lithium hydroxide in a molar ratio of 1:1.05, and 0.5 mol% of WO3 is added. Sintering is carried out under a pure oxygen atmosphere at a temperature of 750℃ for 8h, and after cooling, the polycrystalline primary material Li 1.05 Ni 0.895 Co 0.05 Mn 0.05 W 0.005 O2 is obtained by crushing and sieving.

[0088] (2) The primary material is mixed with 0.33% mol Co3O4, sintering is carried out at 600℃ for 8h, and after cooling, the polycrystalline secondary material Li 1.05 Ni 0.885 Co 0.06 Mn 0.05 W 0.005 O2 is obtained.

[0089] (3) The secondary material is added with 1000 ppm WO3, sintering is carried out under a pure oxygen atmosphere at 400℃ for 6h, and after cooling, the polycrystalline Li 1.05 Ni 0.885 Co 0.06 Mn 0.05 W0.005 O2 cathode material.

[0090] Evaluation method verification:

[0091] The ternary cathode material provided by Preparation Example 1-6 was evaluated using the fast charging performance evaluation method provided by the present disclosure, and at the same time, the ternary cathode material provided by Preparation Example 1-6 was prepared into a button cell for performance test to verify the accuracy of the evaluation method.

[0092] The preparation method is as follows:

[0093] The ternary cathode material provided by Preparation Example, carbon black and PVDF were mixed uniformly according to a mass ratio of 92%:5%:3%, and a certain amount of N-methyl pyrrolidone (NMP) was added, coated on an aluminum foil, and dried to prepare a positive electrode sheet;

[0094] The negative electrode was Li metal, and the button cell was assembled in a glove box with a separator, a positive and negative electrode shell and an electrolyte (1 mol LiPF6, EC:DEC:EMC = 1:1:1).

[0095] The button cell was subjected to 50% SOC DCR test, and the fast charging performance evaluation method provided by the present disclosure was verified using the DCR result, and the test method was as follows: after the button cell was placed for 12 h, the 4C discharge was tested for 10 s;

[0096] The results are shown in Table 1:

[0097] Table 1

[0098]

[0099] From the preparation example and performance test, the fast charging factor k f of the material with a value greater than 0.9 is less than 100 Ω, and it is known in the art that the smaller the DCR value, the shorter the time required for battery charging, i.e. the smaller the DCR value, the better the fast charging performance of the material, therefore, in Table 1, the material with smaller DCR has a higher fast charging factor value and stronger fast charging ability, i.e. the evaluation method provided by the present disclosure can accurately evaluate the charging performance of the ternary cathode material.

[0100] Compared with Preparation Example 1, the preparation method provided by Preparation Example 3 does not have a water washing step for the primary material, and if the water washing step is not introduced, the lithium carbonate in the primary material will affect the fast charging effect of the finally obtained cathode material, therefore, the fast charging performance of Preparation Example 3 is poor, and the comparison results of the fast charging factors of Preparation Example 1 and Preparation Example 3 are the same.

[0101] Compared with Preparation Example 1, the sintering temperature of the preparation method provided by Preparation Example 4 is increased, the particle size of the finally obtained material is increased, and the fast charging performance of the ternary positive electrode material is affected, that is, the fast charging performance of Preparation Example 4 is poor, and the comparison results of the fast charging factors of Preparation Example 1 and Preparation Example 4 are the same.

[0102] Compared with Preparation Example 1, the particle size of the raw material used in the preparation method provided by Preparation Example 5 is large, which can cause the particle size of the finally obtained material to be increased, and the fast charging performance of the ternary positive electrode material is affected, that is, the fast charging performance of Preparation Example 5 is poor, and the comparison results of the fast charging factors of Preparation Example 1 and Preparation Example 5 are the same.

[0103] Therefore, the calculation method of the fast charging factor of the ternary positive electrode material provided by the present disclosure can realize the evaluation of the fast charging performance of the ternary positive electrode material, and the evaluation result is accurate.

[0104] It should be noted that, in this document, relational terms such as "first" and "second", and the like can be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Moreover, the terms "comprises", "comprising", or any other variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but can include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without more limitations, an element preceded by "comprises... " does not, without more limitations, foreclose the existence of additional identical elements in the process, method, article, or apparatus that includes the recited element.

[0105] The above description is merely one specific implementation of the present disclosure, which enables those skilled in the art to understand or implement the present disclosure. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present disclosure. Therefore, the present disclosure will not be limited to these embodiments described herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for evaluating the fast charging performance of a ternary cathode material, characterized in that: The ternary positive electrode material contains Co, and the evaluation method includes: S1. Detect the mass concentration of LiOH m(LiOH) and the mass concentration of Li2CO3 m(Li2CO3) in the ternary positive electrode material, in ppm; detect the specific surface area β of the ternary positive electrode material, in m 2 / g; detecting the molar amount c of Co contained in each mole of the ternary positive electrode material, in mol; detecting the particle size d of the primary particles of the ternary positive electrode material and the particle size D corresponding to when the cumulative particle size distribution percentage reaches 50% 50 , all in μm; the resistivity R of the ternary cathode material in powder state is tested, in Ω·cm; S2. Calculate the ratio α of m(LiOH) and m(Li2CO3), and calculate D 50 The product D of d and d; S3. Calculate the fast charge factor k of the ternary cathode material f , the calculation formula is shown in Formula I; S4. According to the calculated fast charge factor k f And the evaluation criteria are used to determine whether the ternary cathode material is a fast-charging cathode material, wherein the evaluation criteria include: when k f ≥0.9, the ternary positive electrode material is a fast-charging positive electrode material.

2. The evaluation method according to claim 1, wherein: In step S1, m(LiOH) and m(Li2CO3) are obtained by a potentiometric titration method.

3. The evaluation method according to claim 1, wherein: In step S1, β is obtained using the BET test method.

4. The evaluation method according to claim 1, wherein: In step S1, D 50 and d are calculated using the Debye-Scherrer formula.

5. The evaluation method according to any one of claims 1 to 4, characterized in that: The molecular formula of the ternary cathode material is Li x Ni y Co z Mn t M m O2, M is selected from at least one of Al, Zr, Y, Sr, W, Ti, Sb, Ce, Mg, Co, Mo or V, wherein: x, y, z, t, and m represent the molar weight of each molecule in 1 mol of the ternary positive electrode material, mol, y+z+t+m=1, 1<x<1.1, 0≤y<1, 0<z≤1, 0≤t≤0.5, 0<m≤0.

1.

6. The evaluation method according to claim 5, wherein: In the molecular formula of the ternary positive electrode material, M is selected from W, 0.8<y<0.9, 0<z<0.1, 0<t<0.1, and 0<m<0.

01.

7. Application of the evaluation method according to any one of claims 1 to 6 in evaluating the fast charging performance of lithium-ion batteries.

8. A device for evaluating the fast charging performance of a ternary cathode material, characterized in that: include: A detection unit, for detecting the mass concentration of LiOH, the mass concentration of Li2CO3, the specific surface area, the molar amount of Co contained in each mole of the ternary positive electrode material, the particle size of the primary particles, the particle size corresponding to when the cumulative particle size distribution percentage reaches 50%, and the resistivity of the ternary positive electrode material in a powder state; The calculation unit is used to sort and calculate the data detected by the detection unit and output the fast charge factor k f ; Evaluation unit for fast charging factor k f Evaluate whether the ternary cathode material is a fast-charging cathode material.

9. An electronic device, characterized in that: comprising a memory, a processor and a computer program, wherein: The computer program is stored in the memory and is configured to be executed by the processor to implement the evaluation method according to any one of claims 1 to 6.

10. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, the evaluation method according to any one of claims 1 to 6 is implemented.

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