Method and device for determining kinetic index of material

Abstract

The embodiment of the invention provides a method and a device for determining the kinetic index of a material. The performance of a battery is improved while the kinetic index of the material is determined with relatively low complexity. The method comprises the steps that first specific capacity is obtained, the first specific capacity is the specific capacity of a target material under the condition that a charging and discharging device is discharged at a first discharging rate and discharged to a first target voltage of the charging and discharging device, and the charging and discharging device comprises the target material; and determining the kinetic index of the target material according to the first specific capacity.

Description

Technical Field

[0001] This application relates to the technical field of batteries, and in particular, to a method and device for determining the kinetic index of a material Background Art

[0002] Energy conservation and emission reduction are the keys to the sustainable development of the automotive industry. In this context, electric vehicles have become an important part of the sustainable development of the automotive industry due to their advantages of energy conservation and environmental protection. For electric vehicles, battery technology is an important factor related to their development

[0003] In the development of battery technology, the performance of batteries is an issue that cannot be ignored. The performance of batteries not only affects the development and application of battery-related products, but also affects consumers' acceptance of electric vehicles. Therefore, how to improve the performance of batteries is an urgent problem to be solved Summary of the Invention

[0004] Embodiments of this application provide a method and device for determining the kinetic index of a material, which can determine the kinetic index of the material with relatively low complexity while improving the performance of the battery

[0005] In a first aspect, a method for determining the kinetic index of a material is provided, including: obtaining a first specific capacity, where the first specific capacity is the specific capacity of a target material when a charge-discharge device is discharged at a first discharge rate until the cut-off voltage of the charge-discharge device, and the charge-discharge device includes the target material; determining the kinetic index of the target material according to the first specific capacity

[0006] In the embodiments of this application, the kinetic index of the target material is determined according to the specific capacity of the target material when the charge-discharge device is discharged to its first target voltage, that is, the kinetic index of the target material is characterized by the specific capacity. On the one hand, the specific capacity of the target material when discharged to the first target voltage is relatively easy to obtain, and the operation is simple, the cost is low, the efficiency is improved, and the complexity is effectively reduced. On the other hand, if the kinetic index of the target material is determined well according to the specific capacity of the target material, the target material can be used to manufacture a battery. If the kinetic index of the target material is poor, the target material is not used to manufacture a battery, which not only effectively improves the performance of the battery, but also reduces the waste rate of battery resources

[0007] In some possible implementation manners, the method further includes: obtaining a second specific capacity, where the second specific capacity is the specific capacity of the target material when the charge-discharge device is discharged at the first discharge rate until a second target voltage; the determining the kinetic index of the target material according to the first specific capacity includes: determining the kinetic index according to the first specific capacity and the second specific capacity

[0008] In the above technical solution, in addition to the specific capacity of the target material when the charge-discharge device is discharged to the first target voltage at the first discharge rate, the specific capacity of the target material when the charge-discharge device is discharged to the second target voltage at the first discharge rate is also used to determine the kinetic index of the target material, that is, the kinetic index of the target material is determined according to multiple parameters, making the determined kinetic index more accurate.

[0009] In some possible implementation manners, determining the kinetic index according to the first specific capacity and the second specific capacity includes: determining the kinetic index according to the ratio between the second specific capacity and the first specific capacity.

[0010] In the above technical solution, the kinetic index of the target material is determined according to the ratio between the second specific capacity and the first specific capacity, that is, this ratio is used as the quantization index of the difference in the kinetic index of the target material. In this way, the kinetic index of the target material is determined through normalization processing, and then the influence of parameters such as the absolute capacity and mass of different batches of target materials on the kinetic index can be removed, making the finally determined kinetic index the kinetic index itself without the influence of other factors, thereby effectively improving the accuracy rate of the determined kinetic index.

[0011] In some embodiments, the second target voltage is greater than the first target voltage.

[0012] In the above technical solution, the second target voltage is set to be greater than the first target voltage. In this way, the determined kinetic index of the target material is more accurate.

[0013] In some possible implementation manners, the value range of the second target voltage is 2.5V - 3.3V.

[0014] In this way, the difference in the kinetic index between different batches of target materials is relatively obvious, facilitating the distinction of the kinetic indexes of different batches of target materials. In this way, when it is necessary to compare the kinetic indexes of multiple target materials, the user can easily select the ideal target material from multiple target materials. For example, the target material with the best kinetic index, effectively reducing the comparison difficulty for the user.

[0015] In some embodiments, the second target voltage is 3.2V.

[0016] In this technical solution, the second target voltage is set to 3.2V. In this way, relatively speaking, the difference in kinetic indexes between target materials of different batches is the most obvious, which is convenient for distinguishing the kinetic indexes of target materials of different batches. Thus, when it is necessary to compare the kinetic indexes of multiple target materials, the user can easily select an ideal target material from multiple target materials, effectively reducing the difficulty of comparison for the user.

[0017] In some embodiments, the value range of the first target voltage is 1.5V - 2.5V.

[0018] In the above technical solution, the value range of the first target voltage is set to 1.5V - 2.5V. On the one hand, the difference in kinetic indexes between target materials of different batches is relatively obvious, which is convenient for distinguishing the kinetic indexes of target materials of different batches. Thus, when it is necessary to compare the kinetic indexes of multiple target materials, the user can easily select an ideal target material from multiple target materials, effectively reducing the difficulty of comparison for the user. On the other hand, the operation is simple and easy to implement.

[0019] In some embodiments, the first target voltage is 2V.

[0020] In this technical solution, the first target voltage is set to 2V. In this way, relatively speaking, the difference in kinetic indexes between target materials of different batches is the most obvious, which is convenient for distinguishing the kinetic indexes of target materials of different batches. Thus, when it is necessary to compare the kinetic indexes of multiple target materials, the user can easily select an ideal target material from multiple target materials, effectively reducing the difficulty of comparison for the user.

[0021] In some possible implementation manners, the value range of the first discharge rate is 0.2C - 10C.

[0022] In the above technical solution, the value range of the first discharge rate is set to 0.2C - 10C. In this way, the difference in kinetic indexes between target materials of different batches is obvious, which is convenient for distinguishing the kinetic indexes of target materials of different batches. Thus, when it is necessary to compare the kinetic indexes of multiple target materials, the user can easily select an ideal target material from multiple target materials, for example, the target material with the best kinetic indexes, thereby effectively reducing the difficulty of comparison for the user.

[0023] In some possible implementation manners, the value range of the first discharge rate is 0.33C - 2C.

[0024] In this technical solution, the value range of the first discharge rate is set to 0.33C - 2C. Not only can the difference in kinetic indicators between target materials of different batches reach the maximum, but it is also relatively simple to implement, thereby improving the efficiency of determining the kinetic indicators of target materials.

[0025] In some possible implementation manners, the first discharge rate is 1C. In this way, relatively speaking, the difference in kinetic indicators between target materials of different batches can reach the maximum, so that the determined kinetic indicators can better reflect the kinetic performance of the target materials.

[0026] In some possible implementation manners, the method further includes: charging the charge-discharge device at a first charge rate, where the first charge rate is greater than or equal to the first discharge rate.

[0027] In the above technical solution, the charge-discharge device is charged at a relatively large charge rate. For example, before discharging the charge-discharge device at the first discharge rate, the charge-discharge device is charged at a relatively large charge rate. In this way, the charging duration can be greatly reduced, improving the overall measurement efficiency. In addition, it provides a basis for the process of discharging the charge-discharge device at the first discharge rate.

[0028] In some possible implementation manners, charging the charge-discharge device at the first charge rate includes: charging the charge-discharge device at the first charge rate until the target material is completely delithiated.

[0029] In the above technical solution, the charge-discharge device is charged until the target material is completely delithiated, that is, the lithium ions in the target material are completely removed, so that the process of lithium ion insertion can be used to characterize the difference in kinetic indicators between different target materials, and the accuracy is relatively high.

[0030] In some possible implementation manners, the method further includes: performing an activation treatment on the charge-discharge device.

[0031] In the above technical solution, performing an activation treatment on the charge-discharge device, for example, performing an activation treatment on the charge-discharge device before discharging the charge-discharge device at the first discharge rate, can achieve the consistency between different charge-discharge devices and effectively reduce the influence of other factors on the kinetic indicators.

[0032] In some possible implementation manners, performing the activation treatment on the charge-discharge device includes: performing at least one charge-discharge on the charge-discharge device at a second charge-discharge rate, where the second charge-discharge rate is less than or equal to 0.1C.

[0033] In the above technical solution, the charge-discharge rate during the activation treatment is set to be relatively small, which is relatively simple to implement and expands the application scenarios of the charge-discharge device.

[0034] In some possible implementation manners, the charge-discharge device is a button battery.

[0035] Since the manufacturing process of button batteries is relatively simple and it usually takes only about 20 hours to manufacture a button battery. Therefore, the above technical solution using button batteries greatly reduces the time cost and improves the efficiency.

[0036] In a second aspect, a device for measuring kinetic indexes is provided, including: an acquisition unit configured to acquire a first specific capacity, where the first specific capacity is the specific capacity of a target material when the charge-discharge device is discharged at a first discharge rate until a first target voltage of the charge-discharge device, and the charge-discharge device includes the target material; and a determination unit configured to determine the kinetic index of the target material according to the first specific capacity.

[0037] In some possible implementation manners, the acquisition unit is further configured to: acquire a second specific capacity, where the second specific capacity is the specific capacity of the target material when the charge-discharge device is discharged at the first discharge rate until a second target voltage; and the determination unit is specifically configured to: determine the kinetic index according to the first specific capacity and the second specific capacity.

[0038] In some possible implementation manners, the determination unit is specifically configured to: determine the kinetic index according to the ratio between the second specific capacity and the first specific capacity.

[0039] In some possible implementation manners, the second target voltage is greater than the first target voltage.

[0040] In some possible implementation manners, the value range of the second target voltage is 2.5V - 3.3V.

[0041] In some possible implementation manners, the second target voltage is 3.2V.

[0042] In some possible implementation manners, the value range of the first target voltage is 1.5V - 2.5V.

[0043] In some possible implementation manners, the first target voltage is 2V.

[0044] In some possible implementation manners, the value range of the first discharge rate is 0.2C - 10C.

[0045] In some possible implementation manners, the value range of the first discharge rate is 0.33C - 2C.

[0046] In some possible implementation manners, the first discharge rate is 1C.

[0047] In some possible implementation manners, the device further includes: a charging unit, configured to charge the charge-discharge device at a first charging rate, where the first charging rate is greater than or equal to the first discharge rate.

[0048] In some possible implementation manners, the charging unit is specifically configured to: charge the charge-discharge device at the first charging rate until the target material is completely de-lithiated.

[0049] In some possible implementation manners, the device further includes: an activation unit, configured to perform activation processing on the charge-discharge device.

[0050] In some possible implementation manners, the activation unit is specifically configured to: perform at least one charge-discharge on the charge-discharge device at a second charge-discharge rate, where the second charge-discharge rate is less than or equal to 0.1C.

[0051] In some possible implementation manners, the charge-discharge device is a button cell.

[0052] In a third aspect, a device for measuring kinetic indexes is provided, including a processor and a memory, where the memory is used to store a computer program, and the processor is used to call the computer program to execute the method in the first aspect or its various implementation manners above.

[0053] In a fourth aspect, a computer-readable storage medium is provided, used to store a computer program, and the computer program enables a computer to execute the method in the first aspect or its various implementation manners above. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] To more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings required to be used in the embodiments of the present application. Obviously, the following described drawings are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained according to the drawings without creative efforts.

[0055] In the drawings, the drawings are not drawn to actual scale.

[0056] Figure 1 It is a schematic diagram of a vehicle according to an embodiment of the present application.

[0057] Figure 2It is a schematic diagram of the method for determining kinetic indexes according to an embodiment of the present application.

[0058] Figure 3 It is a possible process flow diagram for manufacturing a button battery according to an embodiment of the present application.

[0059] Figure 4 It is a discharge curve diagram of discharging a charge-discharge device at a large discharge rate according to an embodiment of the present application.

[0060] Figure 5 It is a schematic diagram of another method for determining kinetic indexes according to an embodiment of the present application.

[0061] Figure 6 It is a schematic diagram of the ratio between the second specific capacity and the first specific capacity and the DCR deterioration ratio of a battery cell according to an embodiment of the present application.

[0062] Figure 7 It is another schematic diagram of the ratio between the second specific capacity and the first specific capacity and the DCR deterioration ratio of a battery cell according to an embodiment of the present application.

[0063] Figure 8 It is a schematic block diagram of the device for determining kinetic indexes according to an embodiment of the present application.

[0064] Figure 9 It is a schematic block diagram of the device for determining kinetic indexes according to an embodiment of the present application. Detailed implementation manners

[0065] The following further describes the implementation manners of the present application in detail with reference to the drawings and embodiments. The detailed descriptions and drawings of the following embodiments are used to exemplarily illustrate the principle of the present application, but cannot be used to limit the scope of the present application, that is, the present application is not limited to the described embodiments.

[0066] In the description of the present application, it should be noted that unless otherwise specified, the meaning of "a plurality of" is more than two; the orientation or positional relationship indicated by terms such as "upper", "lower", "left", "right", "inner", "outer", etc. is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to the present application. In addition, terms such as "first", "second", "third", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0067] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by those of ordinary skill in the technical field to which this application belongs; the terms used in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "comprising" and "having" and any variations thereof in the specification and claims of this application and the above drawings are intended to cover non-exclusive inclusion. The terms "first", "second", etc. in the specification and claims of this application or the above drawings are used to distinguish different objects and not to describe a specific order or primary-secondary relationship.

[0068] Reference to "embodiment" in this application means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of this application. The phrase appears in various places in the specification and does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments. Those skilled in the art will explicitly and implicitly understand that the embodiments described in this application can be combined with other embodiments.

[0069] In the field of new energy, a battery can be used as the main power source of an electrical device (such as a vehicle, a ship, or a spacecraft, etc.). The battery mentioned in the embodiments of this application refers to a single physical module including one or more battery cells to provide a higher voltage and capacity. For example, the battery mentioned in this application can include a battery module or a battery pack, etc.

[0070] A battery cell includes an electrode assembly and an electrolyte. The electrode assembly is composed of a positive electrode tab, a negative electrode tab, and a separator. The battery cell mainly operates by the movement of metal ions between the positive electrode tab and the negative electrode tab. The positive electrode tab includes a positive electrode current collector and a positive electrode active material layer. The positive electrode active material layer is coated on the surface of the positive electrode current collector. The positive electrode current collector without the coated positive electrode active material layer protrudes from the positive electrode current collector with the coated positive electrode active material layer. The positive electrode current collector without the coated positive electrode active material layer serves as the positive electrode ear. Taking a lithium-ion battery as an example, the material of the positive electrode current collector can be aluminum, and the positive electrode active material can be lithium cobaltate, lithium iron phosphate, ternary lithium, or lithium manganate, etc. The negative electrode tab includes a negative electrode current collector and a negative electrode active material layer. The negative electrode active material layer is coated on the surface of the negative electrode current collector. The negative electrode current collector without the coated negative electrode active material layer protrudes from the negative electrode current collector with the coated negative electrode active material layer. The negative electrode current collector without the coated negative electrode active material layer serves as the negative electrode ear. The material of the negative electrode current collector can be copper, and the negative electrode active material can be carbon or silicon, etc. In order to achieve passing a large current without fusing, the number of positive electrode ears is multiple and stacked together, and the number of negative electrode ears is multiple and stacked together. The material of the separator can be polypropylene (PP) or polyethylene (PE), etc.

[0071] For the same material used to prepare batteries, the performance of materials in different batches (such as the kinetic performance of the active material mentioned above) is good or bad. However, currently, at the stage of warehousing registration of these materials, the performance of these materials is usually not tested. If the kinetic performance of the material is poor, it may cause the specific capacity of the battery monomers prepared with these materials to be abnormal and the directive current resistance (DCR) to fluctuate greatly, which may further lead to frequent problems with the quality of battery monomers and even batteries during mass production.

[0072] Exemplarily, the kinetic performance can represent the ability or ease of lithium ion insertion and extraction of material kinetics. The better the lithium ion insertion and extraction ability of the material, the better the kinetic performance of the material, the faster the process of lithium ions entering the interior of the material and redistributing inside, and the better the performance of the battery prepared with this material.

[0073] Currently, most of the batteries on the market are lithium ion batteries. The process of lithium ion insertion and extraction is the key to the normal operation of lithium ion batteries, which determines the performance and life of lithium ion batteries. During the use of the battery, the insertion and extraction of lithium ions will continuously occur, which will cause changes in the positive and negative electrode materials of the battery, thereby affecting the performance and life of the battery. The insertion process refers to the process in which lithium ions enter the negative electrode of the battery from the positive electrode of the battery. During this process, lithium ions will pass through the electrolyte and the separator and enter the negative electrode material of the battery. The extraction process refers to the process in which lithium ions leave the negative electrode of the battery and return to the positive electrode of the battery. During this process, lithium ions will pass through the electrolyte and the separator and return to the positive electrode material of the battery.

[0074] The specific capacity of the material can be used to evaluate the kinetic performance of the material. Based on this, the embodiments of the present application propose a method for measuring kinetic indicators. By obtaining the first specific capacity and determining the kinetic indicators of the target material according to the first specific capacity, where the first specific capacity is the specific capacity of the target material when the charge-discharge device is discharged at the first discharge rate until the first target voltage is reached, and the charge-discharge device includes the target material. That is, the kinetic indicators of the target material are characterized by the specific capacity. On the one hand, the specific capacity of the target material when discharged to the first target voltage is relatively easy to obtain, the operation is simple, the cost is low, the efficiency is improved, and the complexity is effectively reduced. On the other hand, if the kinetic indicators of the target material are determined to be good according to the specific capacity of the target material, the target material can be used to manufacture batteries. If the kinetic indicators of the target material are poor, the target material is not used to manufacture batteries, which not only effectively improves the performance of the battery, but also reduces the waste rate of battery resources.

[0075] The technical solutions described in the embodiments of the present application are applicable to various electrical equipment using batteries.

[0076] Electrical equipment may be, for example, vehicles, mobile phones, portable devices, laptops, ships, spacecraft, electric toys, and electric tools, etc. Vehicles may be fuel vehicles, gas vehicles, or new energy vehicles, and new energy vehicles may be pure electric vehicles, hybrid vehicles, or extended-range vehicles, etc.; spacecraft include airplanes, rockets, space shuttles, and spacecraft, etc.; electric toys include fixed or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, etc.; electric tools include metal cutting electric tools, grinding electric tools, assembly electric tools, and railway electric tools, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete vibrators, and electric planers, etc. The embodiments of the present application do not impose any special restrictions on the above-mentioned electrical equipment.

[0077] The following text will use the electric equipment as a vehicle as an example for explanation, but it should be understood that the embodiments of the present application are not limited to this.

[0078] Figure 1 The schematic diagram of the structure of a vehicle is shown in one embodiment of the present application. Figure 1 As shown, the vehicle 1 can be a fuel vehicle, a gas vehicle or a new energy vehicle, and the new energy vehicle can be a pure electric vehicle, a hybrid vehicle or an extended-range vehicle, etc. A motor 40, a controller 30 and a battery 10 can be arranged inside the vehicle 1, and the controller 30 is used to control the battery 10 to power the motor 40. For example, a battery 10 can be arranged at the bottom, front or rear of the vehicle 1. The battery 10 can be used to power the vehicle 1. For example, the battery 10 can be used as an operating power source for the vehicle 1, for the circuit system of the vehicle 1, for example, for the working power requirements of the vehicle 1 during startup, navigation and operation. In another embodiment of the present application, the battery 10 can not only be used as an operating power source for the vehicle 1, but also as a driving power source for the vehicle 1, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1.

[0079] Figure 2 FIG. 2 is a schematic flow chart of a method 200 for determining a material kinetic index according to an embodiment of the present application. Figure 2 As shown, method 200 may include at least part of the following contents.

[0080] S210: Obtaining a first specific capacity, wherein the first specific capacity is the specific capacity of the target material when the charge-discharge device is discharged at a first discharge rate and discharged to a first target voltage of the charge-discharge device, and the charge-discharge device includes the target material.

[0081] S220: Determine a kinetic index of the target material according to the first specific capacity.

[0082] It should be understood that the larger the first specific capacity is, the more electric charge the target material releases under the condition that other parameters are the same, and the better the kinetic index of the target material is.

[0083] The kinetic index of the target material can be used to represent the kinetic performance of the target material or the kinetic performance of the charge-discharge device made of the target material. For example, the kinetic index of the target material can be used to reflect the ability of the target material to intercalate and deintercalate lithium ions kinetically or to reflect the ability of the battery made of the target material to intercalate and deintercalate lithium ions.

[0084] In the embodiments of the present application, the kinetic index of the target material is determined according to the specific capacity of the target material when the charge-discharge device is discharged to the first target voltage, that is, the kinetic index of the target material is characterized by the specific capacity. On the one hand, the specific capacity of the target material when discharged to the first target voltage is relatively easy to obtain, and the operation is simple, the cost is low, the efficiency is improved and the complexity is effectively reduced. On the other hand, the specific capacity of the target material is closely related to the kinetic index. If the kinetic index of the target material is preferably determined according to the specific capacity of the target material, the target material can be used to manufacture the battery. If the kinetic index of the target material is poor, the target material is not used to manufacture the battery, which not only effectively improves the performance of the battery, but also reduces the waste rate of battery resources.

[0085] Among them, the target material can be an active material, such as a positive electrode active material. The positive electrode active material can be, for example, lithium cobaltate, lithium iron phosphate, ternary lithium or lithium manganate, etc.

[0086] The specific value of the first target voltage can be determined based on the characteristics of the target material. For example, the first target voltage can be the cut-off voltage of the target material.

[0087] In the embodiments of the present application, the value range of the first target voltage can be greater than or equal to 0V. For example, the value range of the first target voltage can be 0V - 0.5V, 0.5V - 1V, 1V - 1.5V, 1.5V - 2.5V, 3V - 3.8V, etc.

[0088] In the above technical solution, the value range of the first target voltage is set to 1.5V - 2.5V. On the one hand, the difference in the kinetic indexes between different batches of target materials is relatively obvious, which is convenient for distinguishing the kinetic indexes of different batches of target materials. In this way, when it is necessary to compare the kinetic indexes of multiple target materials, the user can easily select the ideal target material from multiple target materials, effectively reducing the comparison difficulty of the user. On the other hand, the operation is simple and easy to implement.

[0089] Exemplarily, the first target voltage can be 2V. By setting the first target voltage to 2V, relatively speaking, the difference in kinetic indicators between target materials of different batches is the most obvious, facilitating the differentiation of the kinetic indicators of target materials of different batches. In this way, in the case where it is necessary to compare the kinetic indicators of multiple target materials, the user can easily select the ideal target material from multiple target materials, effectively reducing the difficulty of comparison for the user.

[0090] The charge-discharge device can be a large battery made of the target material, such as a laminated battery.

[0091] Alternatively, considering that it takes a long time to manufacture a large battery, Method 200 is usually applied in the warehousing registration stage, when it is necessary to quickly determine the kinetic indicators of the target material. If the charge-discharge device is manufactured as a large battery using the target material, it will take a long time.

[0092] Therefore, the charge-discharge device can be a small battery, such as a button battery.

[0093] Figure 3 Shows a possible process flow diagram for manufacturing a button battery. Among them, Figure 3 the target material in is lithium iron phosphate.

[0094] First, weighing is performed. Specifically, lithium iron phosphate, a conductive agent, and polyvinylidene difluoride (PVDF) are calculated according to mass fractions of 80%-97%, 1%-10%, and 2%-10% respectively, and the amount of N-methylpyrrolidone (NMP) is calculated according to the requirement of a solid content of 25%-65%, and weighed with an electronic balance. As an example, the ratios of lithium iron phosphate, the conductive agent, and PVDF can be 90%, 5%, and 5% respectively.

[0095] Second, stirring is performed. Specifically, PVDF, the conductive agent, and lithium iron phosphate are sequentially added to NMP and stirred evenly to obtain a slurry. As an example, the actual solid content of NMP used can be 40%.

[0096] Next, coating is performed. That is, the slurry is evenly coated on both sides of the aluminum foil through an automatic coater to obtain a pole piece. Among them, the coating thickness can be 200μm.

[0097] After coating, air-blowing drying is performed. For example, the pole piece obtained in the previous step can be placed in a 100°C air-blowing drying oven and dried for 2 hours.

[0098] After that, cold pressing and punching are carried out. Exemplarily, cold pressing can be performed with a compaction of 1.4 g / cm3 - 1.8 g / cm3, and then punched into small round pieces with a diameter of 14 mm, and placed in a vacuum oven for drying. After drying is completed, transfer to a glove box for assembly.

[0099] Finally is the assembly process. Specifically, in the glove box, a lithium metal sheet is used as the negative electrode, a lithium iron phosphate electrode sheet is used as the positive electrode, nickel foam is used as the support sheet, and lithium hexafluorophosphate and a mixed carbonate-based organic solvent are used as the electrolyte for assembly, so that a button battery can be obtained.

[0100] After the button battery is assembled, the button battery can be placed in a constant temperature room or a high and low temperature chamber, and the temperature is controlled within a certain range, for example, controlled at 25°C ± 2°C, to execute method 200.

[0101] Since the manufacturing process of the button battery is relatively simple, it usually only takes about 20 hours to manufacture the button battery. Therefore, the above technical solution uses a button battery, which greatly reduces the time cost and improves the efficiency.

[0102] There is polarization during the discharge process of the battery. Generally, the greater the discharge current density, the greater the polarization. Usually, the polarization of a lithium-ion battery can be divided into ohmic polarization, electrochemical polarization, and concentration polarization. Among them, ohmic polarization refers to the polarization caused by the ohmic internal resistance of the lithium-ion battery. The ohmic internal resistance of the lithium-ion battery consists of the electrode material, electrolyte, separator resistance, and the contact resistance of each part of the component. Electrochemical polarization refers to the polarization caused by the fact that the electrochemical reaction rate on the positive and negative electrodes is less than the electron movement rate. Concentration polarization refers to the polarization caused by the fact that the diffusion rate of lithium ions participating in the reaction in the solid phase is less than the electrochemical reaction rate. Among them, the solid-phase diffusion ability is the main factor affecting the kinetic index of the material.

[0103] If the charge and discharge device is discharged at a small discharge rate, the discharge curves of the charge and discharge devices obtained using target materials of different batches basically coincide, and there is no obvious difference in the kinetic indexes of the target materials of different batches.

[0104] Figure 4 The discharge curve graph of discharging the charge and discharge device at a large discharge rate is shown. Among them, the abscissa is the specific capacity of the target material, and the ordinate is the voltage. It can be seen that when a large discharge rate is adopted, the kinetic indexes of the target materials of different batches affected by the solid-phase diffusion ability are quite different, and thus the kinetic indexes of the target materials of different batches can be distinguished.

[0105] Therefore, the first discharge rate in the embodiments of the present application can be relatively large. If the charge-discharge device is a button battery, the first discharge rate cannot be too large either. In summary, the value range of the first discharge rate can be 0.2C - 10C. Exemplarily, the first discharge rate can be 0.3C, 0.5C, 3C, 3.5C, 4C, 4.5C, 5C, 6C, etc.

[0106] In this way, the differences in kinetic indexes between target materials of different batches are relatively obvious, which is convenient for distinguishing the kinetic indexes of target materials of different batches. Thus, in the case where it is necessary to compare the kinetic indexes of multiple target materials, the user can easily select an ideal target material from multiple target materials, for example, the target material with the best kinetic indexes, thereby effectively reducing the comparison difficulty for the user.

[0107] Furthermore, the value range of the first discharge rate can be 0.33C - 2C.

[0108] In this technical solution, by setting the value range of the first discharge rate to 0.33C - 2C, not only can the differences in kinetic indexes between target materials of different batches reach the maximum, but also it is relatively simple to implement, thereby improving the efficiency of determining the kinetic indexes of target materials.

[0109] For example, the first discharge rate can be 0.6C, 1C, 1.5C, etc. When the first discharge rate is 1C, relatively speaking, the differences in kinetic indexes between target materials of different batches can reach the maximum, so that the determined kinetic indexes can better reflect the kinetic performance of the target materials.

[0110] Considering that there may be differences in the absolute capacity, mass, etc. of target materials of different batches, these differences may affect the judgment of kinetic indexes. To eliminate the influence brought by these differences, further, as Figure 5 shown, method 200 may further include:

[0111] S211: Obtain a second specific capacity, where the second specific capacity is the specific capacity of the target material when the charge-discharge device is discharged at the first discharge rate until the second target voltage.

[0112] At this time, S220 may specifically include: determining the kinetic index of the target material according to the first specific capacity and the second specific capacity.

[0113] The embodiments of the present application do not make specific limitations on the order of obtaining the first specific capacity and the second specific capacity. For example, the first specific capacity can be obtained first and then the second specific capacity, or the second specific capacity can be obtained first and then the first specific capacity, or the first specific capacity and the second specific capacity can be obtained simultaneously.

[0114] In the above technical solution, in addition to the specific capacity of the target material when the charge-discharge device is discharged to the first target voltage at the first discharge rate, the specific capacity of the target material when the charge-discharge device is discharged to the second target voltage at the first discharge rate is also used to determine the kinetic index of the target material, that is, the kinetic index of the target material is determined based on multiple parameters, making the determined kinetic index more accurate.

[0115] In some embodiments, the second target voltage can be greater than the first target voltage. For example, if the first target voltage is 1V, the second target voltage can be 1.5V, 2V, 3.5V, etc. In this way, the determined kinetic index of the target material is more accurate.

[0116] Referring again to Figure 4 , it can be seen that when the second target voltage is in the range of 2.5V - 3.3V, the difference in the specific capacity of the target material in different batches is relatively obvious, which is convenient for users to distinguish the kinetic indexes of the target material in different batches.

[0117] Therefore, in the embodiments of the present application, the value range of the second target voltage can be 2.5V - 3.3V. In this way, the difference in the kinetic indexes between the target materials in different batches is relatively obvious, which is convenient for distinguishing the kinetic indexes of the target materials in different batches. In this way, when it is necessary to compare the kinetic indexes of multiple target materials, users can easily select the ideal target material from multiple target materials. For example, the target material with the best kinetic index effectively reduces the comparison difficulty for users.

[0118] For example, the second target voltage can be 2.8V, 3V, 3.2V, etc. When the second target voltage is 3.2V, relatively speaking, the difference in the kinetic indexes between the target materials in different batches is the most obvious, which is convenient for distinguishing the kinetic indexes of the target materials in different batches. In this way, when it is necessary to compare the kinetic indexes of multiple target materials, users can easily select the ideal target material from multiple target materials, effectively reducing the comparison difficulty for users.

[0119] As an example, the kinetic index of the target material can be determined according to the difference between the first specific capacity and the second specific capacity.

[0120] As another example, the kinetic index of the target material can be determined according to the ratio of the second specific capacity to the first specific capacity.

[0121] Among them, the larger the ratio, that is, the target material with a higher proportion of the second specific capacity, the smaller the concentration polarization affected by the solid-phase diffusion ability of the target material, the smaller the diffusion impedance of the target material, the better the kinetic index of the target material, and the lower the risk of DCR deterioration of the corresponding battery cell.

[0122] Figure 6 It shows a schematic diagram of the ratio mentioned above and the DCR deterioration ratio of the charge-discharge device at a 10% state of charge (SOC). Figure 6 The target material in it is lithium iron phosphate, the first discharge rate is 1C, the second target voltage is 3.2V, the abscissa is the ratio between the second specific capacity and the first specific capacity, and the ordinate is the DCR deterioration ratio.

[0123] From Figure 6 It can be seen that the larger the ratio between the second specific capacity and the first specific capacity, the lower the deterioration risk of the DCR of the charge-discharge device including the target material, and the better the kinetic index of the target material.

[0124] In the above technical solution, the kinetic index of the target material is determined according to the ratio between the second specific capacity and the first specific capacity, that is, this ratio is used as the quantization index of the difference in the kinetic index of the target material. In this way, the kinetic index of the target material is determined through normalization processing, and then the influence of parameters such as the absolute capacity and mass of different batches of target materials on the kinetic index can be removed, so that the finally determined kinetic index is the kinetic index itself without the influence of other factors, thereby effectively improving the accuracy of the determined kinetic index.

[0125] It should be noted that the specific capacity in the embodiments of the present application can also be referred to as gram capacity.

[0126] Table 1 shows a part of the test data of the embodiments of the present application. Among them, the first discharge rate is 1C.

[0127] Table 1

[0128]

[0129] It can be seen from Table 1 that when the charge-discharge device is discharged to 3.2V, the specific capacity of the target material is 110.4675 mAh / g, and when it is discharged to 2V, the specific capacity of the target material is 130.103 mAh / g, then the capacity ratio of the two is 110.4675 / 130.103 = 84.9%.

[0130] Furthermore, method 200 may further include: determining whether the ratio between the second specific capacity and the first specific capacity is within a preset range.

[0131] Among them, the preset range can be determined based on the characteristics of the target material. That is, if the target material is different, the preset range may be different. For example, when the target material is lithium iron phosphate, the preset range can be 1-3. If the ratio of the second specific capacity to the first specific capacity is within the range of 1-3, it indicates that the kinetic index of lithium iron phosphate or the kinetic index of the charge and discharge device made of lithium iron phosphate is good.

[0132] Further, method 200 may further include: charging the charge and discharge device at a first charging rate.

[0133] Among them, before discharging the charge and discharge device at a first discharge rate, the charge device can be charged at a first charging rate.

[0134] The first charging rate can be relatively small. For example, it can be 0.1C.

[0135] Alternatively, the first charging rate can be relatively large. For example, the first charging rate can be greater than or equal to the first discharge rate, such as 1C, 2C, 3C, etc. In this way, the charging time can be greatly reduced, improving the overall measurement efficiency. In addition, it provides a basis for the process of discharging the charge and discharge device at a first discharge rate.

[0136] Optionally, when charging the charge and discharge device at a first charging rate, it can be charged until the target material is completely de-lithiated. In other words, until the lithium ions in the target material are completely removed.

[0137] In this technical solution, the charge and discharge device is charged until the target material is completely de-lithiated, that is, the lithium ions in the target material are completely removed, so that the process of lithium ion insertion can be used to characterize the differences in kinetic indexes between different target materials, and the accuracy is relatively high.

[0138] After charging the charge and discharge device at a constant current (CC) at a first charging rate, the charge and discharge device can also be charged at a constant voltage (CV). At this time, after constant voltage charging, the target material can be in a completely de-lithiated state.

[0139] In order to achieve consistency between different charge and discharge devices, so that the finally obtained kinetic indexes can be as little affected by other factors as possible. Therefore, before S210, method 200 may further include: performing an activation treatment on the charge and discharge device.

[0140] In this way, consistency between different charge and discharge devices can be achieved, effectively reducing the influence of other factors on the kinetic indexes.

[0141] In some embodiments, the activation process of the charge-discharge device may include: performing at least one charge and discharge on the charge-discharge device at a second charge-discharge rate.

[0142] The second charge-discharge rate can be relatively large. For example, the second charge-discharge rate can be 1C, 2C, 3C, 5C, 10C, etc.

[0143] Alternatively, the second charge-discharge rate can be relatively small, such as less than or equal to 0.1C. For example, the second charge-discharge rate can be 0.05C, 0.02C, etc. In the above technical solution, setting the charge-discharge rate during the activation process to be small is relatively simple to implement and expands the application scenarios of the charge-discharge device. For example, the charge-discharge device can be a button battery.

[0144] To further prove the correlation between the kinetic indexes of the target material and the DCR of the charge-discharge device including the target material, the embodiments of the present application respectively tested five charge-discharge devices made of lithium iron phosphate in five batches at a temperature of 25°C and a temperature of -20°C.

[0145] First, the charge-discharge device is activated at a small rate. Specifically, five batches of charge-discharge devices are first left standing. Optionally, considering efficiency and sufficient wettability, the standing time can be 3 hours to 5 hours, for example, 4 hours, to allow the electrolyte to fully infiltrate into the electrode sheets. It should be understood that the standing times of the five charge-discharge devices are the same. Then, the charge-discharge device is subjected to constant-current charging at a constant charging rate of 0.1C until the voltage of the charge-discharge device reaches 3.75V, and then the charge-discharge device is subjected to constant-voltage charging at a constant voltage of 3.75V until the current of the charge-discharge device reaches 50 μA. Then the charge-discharge device is left standing. Exemplarily, the five charge-discharge devices can all be left standing for 5 minutes. After that, the charge-discharge device is discharged at a discharge rate of 0.1C (discharge, DC) to 2.0V, and then the five charge-discharge devices are all left standing for 5 minutes.

[0146] Next, the charge-discharge device is subjected to constant-current charging at a constant charging rate of 1C until the voltage of the charge-discharge device reaches 3.75V, and then the charge-discharge device is subjected to constant-voltage charging at a constant voltage of 3.75V until the current of the charge-discharge device reaches 50 μA. Then, the five charge-discharge devices are all left standing for 5 minutes.

[0147] After the standing is completed, the kinetic indexes of lithium iron phosphate are measured at a large discharge rate. Specifically, the charge-discharge device is discharged at a discharge rate of 1C to the cut-off voltage of lithium iron phosphate (for example, 2.0V), so that the first specific capacity can be obtained.

[0148] The process of obtaining the second specific capacity is similar to that of obtaining the first specific capacity, except that at the end of the steps, the charge-discharge device is discharged to the second target voltage (e.g., 3.2V) at a discharge rate of 1C, so that the second specific capacity can be obtained.

[0149] It should be noted that the step of leaving the charge-discharge device static for 5 minutes in the above steps can be understood as a transition in the process. The static time of different charge-discharge devices can be the same or different. Considering the test efficiency, the above steps leave 5 charge-discharge devices static for 5 minutes. Of course, the static time can also be other times, such as 10 minutes, 30 minutes, etc.

[0150] Based on the test data obtained from the above test process, it can be obtained that Figure 7 . Among them, the ordinate is the proportion of DCR deterioration at a temperature of 25°C and 10% SOC, and the abscissa is the ratio between the second specific capacity and the first specific capacity. The expression obtained by fitting this proportion and ratio can be expressed as y = -1.5199x + 1.467, and the correlation coefficient is 0.9271.

[0151] Table 2 shows the test data obtained by using the above test process. Among them, the unit of specific capacity is mAh / g, DCR deterioration ratio 1 is the proportion of DCR deterioration at a temperature of 25°C and 10% SOC, and DCR deterioration ratio 2 is the proportion of DCR deterioration at a temperature of -20°C and 10% SOC.

[0152] Table 2

[0153]

[0154] From Figure 7 and Table 2, it can be seen that, first of all, the kinetic index of lithium iron phosphate has a strong correlation with DCR, and the correlation coefficient can reach 0.9271, and the better the kinetic index, the lower the probability of DCR deterioration. Secondly, the difference in the kinetic indexes of different batches of lithium iron phosphate at low temperature is more obvious.

[0155] It should be understood that Table 1 and Table 2 are only examples and do not limit the scope of the embodiments of the present application.

[0156] In the embodiments of the present application, the magnitudes of the sequence numbers of the above processes do not mean the order of execution, and the execution order of each process should be determined by its function and internal logic, and should not constitute any limitation to the implementation process of the embodiments of the present application.

[0157] Moreover, on the premise of not conflicting, the various embodiments described in the present application and / or the technical features in each embodiment can be combined arbitrarily, and the technical solutions obtained after combination should also fall within the protection scope of the present application.

[0158] The method for measuring kinetic indicators according to the embodiments of the present application is described in detail above. Next, the apparatus for measuring kinetic indicators according to the embodiments of the present application will be described. It should be understood that the apparatus for measuring kinetic indicators in the embodiments of the present application can execute the method for measuring kinetic indicators in the embodiments of the present application.

[0159] Figure 8 FIG. shows a schematic block diagram of an apparatus 700 for measuring kinetic indicators according to an embodiment of the present application. As Figure 8 shown, the apparatus 700 may include:

[0160] An acquisition unit 710, configured to acquire a first specific capacity, where the first specific capacity is the specific capacity of a target material when the charge-discharge device is discharged at a first discharge rate until a first target voltage of the charge-discharge device is reached, and the charge-discharge device includes the target material.

[0161] A determination unit 720, configured to determine a kinetic indicator of the target material according to the first specific capacity.

[0162] Optionally, in an embodiment of the present application, the acquisition unit 710 is further configured to: acquire a second specific capacity, where the second specific capacity is the specific capacity of the target material when the charge-discharge device is discharged at the first discharge rate until a second target voltage is reached.

[0163] The determination unit 720 is specifically configured to: determine the kinetic indicator according to the first specific capacity and the second specific capacity.

[0164] Optionally, in an embodiment of the present application, the determination unit 710 is specifically configured to: determine the kinetic indicator according to a ratio between the second specific capacity and the first specific capacity.

[0165] Optionally, in an embodiment of the present application, the second target voltage is greater than the first target voltage.

[0166] Optionally, in an embodiment of the present application, the value range of the second target voltage is 2.5V - 3.3V.

[0167] Optionally, in an embodiment of the present application, the second target voltage is 3.2V.

[0168] Optionally, in an embodiment of the present application, the value range of the first target voltage is 1.5V - 2.5V.

[0169] Optionally, in an embodiment of the present application, the first target voltage is 2V.

[0170] Optionally, in an embodiment of the present application, the value range of the first discharge rate is 0.2C - 10C.

[0171] Optionally, in an embodiment of the present application, the value range of the first discharge rate is 0.33C - 2C.

[0172] Optionally, in the embodiment of the present application, the first discharge rate is 1C.

[0173] Optionally, in the embodiment of the present application, the device 700 further includes: a charging unit, configured to charge the charge-discharge device at a first charging rate, where the first charging rate is greater than or equal to the first discharge rate.

[0174] Optionally, in the embodiment of the present application, the charging unit is specifically configured to: charge the charge-discharge device at a first charging rate until the target material is completely de-lithiated.

[0175] Optionally, in the embodiment of the present application, the device 700 further includes: an activation unit, configured to perform activation processing on the charge-discharge device.

[0176] Optionally, in the embodiment of the present application, the activation unit is specifically configured to: perform at least one charge-discharge on the charge-discharge device at a second charge-discharge rate, where the second charge-discharge rate is less than or equal to 0.1C.

[0177] Optionally, in the embodiment of the present application, the charge-discharge device is a button cell.

[0178] It should be understood that the device 700 can implement the corresponding operations in the method 200. For the sake of brevity, it will not be elaborated here.

[0179] Figure 9 It is a schematic hardware structure diagram of a device 800 for measuring kinetic indexes in an embodiment of the present application. The device 800 includes a memory 801, a processor 802, a communication interface 803, and a bus 804. Among them, the memory 801, the processor 802, and the communication interface 803 are communicatively connected to each other through the bus 804.

[0180] The memory 801 can be a read-only memory (ROM), a static storage device, and a random access memory (RAM). The memory 801 can store a program. When the program stored in the memory 801 is executed by the processor 802, the processor 802 and the communication interface 803 are used to execute the respective steps of the method for measuring kinetic indexes in the embodiment of the present application.

[0181] The processor 802 may be a general-purpose central processing unit (CPU), a microprocessor, an application specific integrated circuit (ASIC), a graphics processing unit (GPU), or one or more integrated circuits, and is used to execute relevant programs to implement the functions required by the units in the device of the embodiments of the present application, or to execute the method for measuring kinetic indicators of the embodiments of the present application.

[0182] The processor 802 may also be an integrated circuit chip with signal processing capabilities. In the implementation process, each step of the method for measuring kinetic indicators of the embodiments of the present application may be completed by the integrated logic circuit in the hardware of the processor 802 or instructions in the form of software.

[0183] The above-mentioned processor 802 may also be a general-purpose processor, a digital signal processor (DSP), an ASIC, a field programmable gate array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components. It can implement or execute the various methods, steps, and logic block diagrams disclosed in the embodiments of the present application. The general-purpose processor may be a microprocessor or the processor may also be any conventional processor, etc. The steps of the method disclosed in combination with the embodiments of the present application may be directly embodied as being completed by the execution of the hardware processor, or completed by the combination of the hardware and software modules in the processor. The software module may be located in a mature storage medium in the art such as a random access memory, a flash memory, a read-only memory, a programmable read-only memory, or an electrically erasable programmable memory, a register, etc. This storage medium is located in the memory 801, and the processor 802 reads the information in the memory 801 and combines its hardware to complete the functions required by the units included in the device for measuring kinetic indicators of the embodiments of the present application, or to execute the method for measuring kinetic indicators of the embodiments of the present application.

[0184] The communication interface 803 uses a transceiver device such as, but not limited to, a transceiver to achieve communication between the device 800 and other devices or communication networks.

[0185] The bus 804 may include a path for transmitting information between various components of the device 800 (for example, the memory 801, the processor 802, the communication interface 803).

[0186] It should be noted that although the above device 800 only shows a memory, a processor, and a communication interface, in the specific implementation process, those skilled in the art should understand that the device 800 may also include other devices necessary for normal operation. At the same time, according to specific needs, those skilled in the art should understand that the device 800 may also include hardware devices for implementing other additional functions. In addition, those skilled in the art should understand that the device 800 may also only include the devices necessary for implementing the embodiments of the present application, and does not necessarily include Figure 8 all the devices shown in

[0187] The embodiment of the present application also provides a computer-readable storage medium for storing a computer program, and the computer program is used to execute the methods of various embodiments of the present application described above.

[0188] The above computer-readable storage medium may be a transient computer-readable storage medium or a non-transient computer-readable storage medium.

[0189] The embodiment of the present application also provides a computer program product, which includes a computer program stored on a computer-readable storage medium. The computer program includes program instructions, and when the program instructions are executed by a computer, the computer is made to execute the method for measuring kinetic indexes described above.

[0190] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application and are not intended to limit them. Although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of the technical features. However, these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A method for determining the kinetic index of a material, characterized in that, Including: Obtain a first specific capacity, where the first specific capacity is the specific capacity of a target material when discharging a charge-discharge device at a first discharge rate until a first target voltage of the charge-discharge device is reached, and the charge-discharge device includes the target material; Determine a kinetic index of the target material according to the first specific capacity.

2. The method according to claim 1, characterized in that, The method further includes: Obtain a second specific capacity, where the second specific capacity is the specific capacity of the target material when discharging the charge-discharge device at the first discharge rate until a second target voltage is reached; The determining the kinetic index of the target material according to the first specific capacity includes: Determine the kinetic index according to the first specific capacity and the second specific capacity.

3. The method according to claim 2, characterized in that, The determining the kinetic index according to the first specific capacity and the second specific capacity includes: Determine the kinetic index according to a ratio between the second specific capacity and the first specific capacity.

4. The method according to claim 2 or 3, characterized in that, The second target voltage is greater than the first target voltage.

5. The method according to any one of claims 2 to 4, characterized in that, The value range of the second target voltage is 2.5V - 3.3V.

6. The method according to claim 5, characterized in that, The second target voltage is 3.2V.

7. The method according to any one of claims 1 to 6, characterized in that, The value range of the first target voltage is 1.5V - 2.5V.

8. The method according to claim 7, characterized in that, The first target voltage is 2V.

9. The method according to any one of claims 1 to 8, characterized in that, The value range of the first discharge rate is 0.2C - 10C.

10. The method according to claim 9, characterized in that, The value range of the first discharge rate is 0.33C - 2C.

11. The method according to claim 9 or 10, characterized in that, The first discharge rate is 1C.

12. The method according to any one of claims 1 to 11, characterized in that, The method further includes: Charge the charge-discharge device at a first charge rate, where the first charge rate is greater than or equal to the first discharge rate.

13. The method according to claim 12, characterized in that, The charging the charge-discharge device at the first charge rate includes: Charge the charge-discharge device at the first charge rate until the target material is completely de-lithiated.

14. The method according to any one of claims 1 to 13, characterized in that, The method further includes: Perform an activation treatment on the charge-discharge device.

15. The method according to claim 14, characterized in that, The performing the activation treatment on the charge-discharge device includes: Perform at least one charge and discharge on the charge-discharge device at a second charge-discharge rate, where the second charge-discharge rate is less than or equal to 0.1C.

16. The method according to any one of claims 1 to 15, characterized in that The charge-discharge device is a button cell.

17. An apparatus for determining the kinetic index of a material, characterized in that Including: An acquisition unit for obtaining a first specific capacity, where the first specific capacity is the specific capacity of a target material when discharging a charge-discharge device at a first discharge rate until a first target voltage of the charge-discharge device is reached, and the charge-discharge device includes the target material; A determination unit for determining a kinetic index of the target material according to the first specific capacity.

18. The apparatus according to claim 17, characterized in that The acquisition unit is further configured to: Obtain a second specific capacity, where the second specific capacity is the specific capacity of the target material when discharging the charge-discharge device at the first discharge rate until a second target voltage is reached; The determination unit is specifically configured to: Determine the kinetic index according to the first specific capacity and the second specific capacity.

19. The apparatus according to claim 18, characterized in that The determination unit is specifically configured to: Determine the kinetic index according to a ratio between the second specific capacity and the first specific capacity.

20. The apparatus according to claim 18 or 19, characterized in that The second target voltage is greater than the first target voltage.

21. The apparatus according to any one of claims 18 to 20, characterized in that The value range of the second target voltage is 2.5V - 3.3V.

22. The apparatus according to claim 21, characterized in that The second target voltage is 3.2V.

23. The apparatus according to any one of claims 17 to 22, characterized in that The value range of the first target voltage is 1.5V - 2.5V.

24. The apparatus according to claim 23, characterized in that The first target voltage is 2V.

25. The apparatus according to any one of claims 17 to 24, characterized in that The value range of the first discharge rate is 0.2C - 10C.

26. The apparatus according to claim 25, characterized in that The value range of the first discharge rate is 0.33C - 2C.

27. The apparatus according to claim 25 or 26, characterized in that The first discharge rate is 1C.

28. The apparatus according to any one of claims 17 to 27, characterized in that The device further includes: A charging unit for charging the charge-discharge device at a first charging rate, where the first charging rate is greater than or equal to the first discharge rate.

29. The apparatus according to claim 28, characterized in that The charging unit is specifically configured to: Charge the charge-discharge device at the first charging rate until the target material is completely de-lithiated.

30. The apparatus according to any one of claims 17 to 29, characterized in that The device further includes: An activation unit for performing activation processing on the charge-discharge device.

31. The device according to claim 30, wherein The activation unit is specifically configured to: Perform at least one charge and discharge on the charge-discharge device at a second charge-discharge rate, where the second charge-discharge rate is less than or equal to 0.1C.

32. The device according to any one of claims 17 to 31, wherein The charge-discharge device is a button cell.

33. A device for determining the kinetic index of a material, wherein It includes: A memory for storing a program; A processor for executing the program stored in the memory. When the program stored in the memory is executed, the processor is used to execute the method for determining the material kinetic index according to any one of claims 1 to 16.

34. A computer-readable storage medium, wherein For storing a computer program, the computer program causes a computer to execute the method for determining the material kinetic index according to any one of claims 1 to 16.

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