Lithium battery loss analysis method and device, storage medium and electronic equipment

Abstract

The invention discloses a loss analysis method and device of a lithium battery, a storage medium and electronic equipment. The method relates to the field of lithium batteries, and comprises the following steps: obtaining discharge data of a lithium battery in N charge and discharge cycles, N being a positive integer; determining the maximum discharge capacity of the lithium battery in each charge and discharge period based on the discharge data of each charge and discharge period; and for each of the N charge and discharge cycles, calculating loss information of the lithium battery in the charge and discharge cycles according to the initial maximum discharge capacity of the initial charge and discharge cycle and the maximum discharge capacity of the charge and discharge cycle, the loss information comprising at least one of the following: an active lithium loss ratio and active lithium loss mass. The technical problem of low accuracy of analyzing the loss information of the lithium battery in related technologies is solved.

Description

Technical Field

[0001] The present invention relates to the field of lithium batteries, and in particular to a loss analysis method, device, storage medium and electronic equipment for lithium batteries. Background Art

[0002] During the lithium battery cycle, SEI film thickening, lithium precipitation, electrolyte decomposition and dead lithium will all cause active lithium loss (Loss of Lithium Inventory). Active lithium loss is divided into reversible active lithium loss and irreversible active lithium loss. Active lithium loss will affect the cycle performance of the product, causing battery capacity loss. In severe cases, it will lead to battery failure and safety hazards. Therefore, it is very important to analyze the loss of lithium batteries. At present, there is a problem of low accuracy in analyzing the loss information of lithium batteries in related technologies.

[0003] To address the above-mentioned problems, no effective solution has been proposed yet. Summary of the invention

[0004] Embodiments of the present invention provide a lithium battery loss analysis method, device, storage medium and electronic device to at least solve the technical problem of low accuracy in analyzing lithium battery loss information in the related art.

[0005] According to one aspect of an embodiment of the present invention, a loss analysis method for a lithium battery is provided, comprising: obtaining discharge data of a lithium battery in N charge and discharge cycles, wherein N is a positive integer; determining a maximum discharge capacity of the lithium battery in each charge and discharge cycle based on the discharge data of each charge and discharge cycle; for each of the N charge and discharge cycles, calculating loss information of the lithium battery in the charge and discharge cycle according to an initial maximum discharge capacity of the initial charge and discharge cycle and a maximum discharge capacity of the charge and discharge cycle, wherein the loss information comprises at least one of the following: a proportion of active lithium loss and a mass of active lithium loss.

[0006] Furthermore, the loss analysis method of the lithium battery also includes: charging and discharging the lithium battery for one cycle according to a first charging and discharging method, and determining the discharge data in the cycle as the discharge data in N charging and discharging cycles, wherein the charge and discharge rate adopted by the first charging and discharging method is a target charge and discharge rate; charging and discharging the lithium battery for M cycles according to a second charging and discharging method, wherein the second charging and discharging method is a charging method that meets the product specifications of the lithium battery; repeating the steps of charging and discharging the lithium battery for one cycle according to the first charging and discharging method, and charging and discharging the lithium battery for M cycles according to the second charging and discharging method until the discharge data of N charging and discharging cycles are obtained.

[0007] Furthermore, the loss analysis method of the lithium battery also includes: before the initial maximum discharge capacity of the initial charge and discharge cycle and the maximum discharge capacity of the charge and discharge cycle, determining the first cycle of charge and discharge of the lithium battery as the initial charge and discharge cycle, wherein the first cycle adopts a first charge and discharge method to charge and discharge the lithium battery, and the charge and discharge rate adopted by the first charge and discharge method is the target charge and discharge rate.

[0008] Furthermore, the loss analysis method of the lithium battery also includes: calculating the difference between the initial maximum discharge capacity and the maximum discharge capacity of the charge and discharge cycle to obtain the capacity loss value corresponding to the charge and discharge cycle; and calculating the loss information of the lithium battery in the charge and discharge cycle based on the capacity loss value.

[0009] Furthermore, the loss analysis method of the lithium battery also includes: obtaining the Faraday constant and the relative atomic mass of the lithium element; calculating the active lithium loss mass based on the capacity loss value, the Faraday constant and the relative atomic mass of the lithium element, and determining the active lithium loss mass as the loss information.

[0010] Furthermore, the loss analysis method of the lithium battery also includes: calculating the ratio between the capacity loss value and the Faraday constant to obtain a first value; and determining the active lithium loss mass based on the first value and the relative atomic mass of the lithium element.

[0011] Furthermore, the loss analysis method of the lithium battery also includes: calculating the product of the first value and the relative atomic mass of the lithium element to obtain the active lithium loss mass.

[0012] Furthermore, the loss analysis method of the lithium battery also includes: calculating the ratio between the capacity loss value and the initial maximum discharge capacity to obtain the active lithium loss ratio, and determining the active lithium loss ratio as the loss information.

[0013] According to another aspect of an embodiment of the present invention, a loss analysis device for a lithium battery is also provided, including: an acquisition module, used to acquire discharge data of a lithium battery in N charge and discharge cycles, wherein N is a positive integer; a first determination module, used to determine the maximum discharge capacity of the lithium battery in each charge and discharge cycle based on the discharge data of each charge and discharge cycle; a calculation module, used to calculate the loss information of the lithium battery in the charge and discharge cycle for each of the N charge and discharge cycles, according to the initial maximum discharge capacity of the initial charge and discharge cycle and the maximum discharge capacity of the charge and discharge cycle, wherein the loss information includes at least one of the following: the proportion of active lithium loss and the mass of active lithium loss.

[0014] According to another aspect of an embodiment of the present invention, a computer-readable storage medium is provided, in which a computer program is stored, wherein the computer program is configured to execute the above-mentioned lithium battery loss analysis method when running.

[0015] According to another aspect of an embodiment of the present invention, an electronic device is also provided, which includes one or more processors; a memory for storing one or more programs, which, when the one or more programs are executed by the one or more processors, enables the one or more processors to run the programs, wherein the programs are configured to execute the above-mentioned lithium battery loss analysis method when running.

[0016] According to another aspect of an embodiment of the present invention, a computer program product is provided, including a computer program / instruction, and when the computer program / instruction is executed by a processor, the above-mentioned lithium battery loss analysis method is implemented.

[0017] In an embodiment of the present invention, the loss information of the lithium battery is calculated based on the maximum discharge capacity and the initial maximum discharge capacity of the lithium battery in the charge and discharge cycle, by obtaining the discharge data of the lithium battery in N charge and discharge cycles, and then obtaining the discharge data of the lithium battery in N charge and discharge cycles, so that for each charge and discharge cycle in the N charge and discharge cycles, according to the initial maximum discharge capacity of the initial charge and discharge cycle and the maximum discharge capacity of the charge and discharge cycle, the loss information of the lithium battery in the charge and discharge cycle is calculated. Wherein, N is a positive integer, and the loss information includes at least one of the following: active lithium loss ratio, active lithium loss mass.

[0018] In the above process, by acquiring the discharge data of the lithium battery in N charge and discharge cycles, and determining the maximum discharge capacity of the lithium battery in each charge and discharge cycle based on the discharge data of each charge and discharge cycle, the battery performance data of the lithium battery in the cycle process is effectively acquired. By calculating the loss information of the lithium battery in the charge and discharge cycle according to the initial maximum discharge capacity of the initial charge and discharge cycle and the maximum discharge capacity of the charge and discharge cycle, the loss information of the lithium battery in the cycle process is calculated based on the attenuation of the lithium battery, thereby effectively improving the accuracy of the calculated loss information.

[0019] It can be seen that the solution provided in the present application achieves the purpose of calculating the loss information of the lithium battery based on the maximum discharge capacity and the initial maximum discharge capacity of the lithium battery during the charge and discharge cycle, thereby achieving the technical effect of improving the accuracy of the calculated loss information, and further solving the technical problem of low accuracy in analyzing the loss information of lithium batteries in the related art. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of this application. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0021] Figure 1is a schematic diagram of an optional loss analysis method of a lithium battery according to an embodiment of the present invention;

[0022] Figure 2 is a schematic diagram of an optional Q-dV / dQ curve according to an embodiment of the present invention;

[0023] Figure 3 is a schematic diagram of optional loss information according to an embodiment of the present invention;

[0024] Figure 4 is a schematic diagram of an optional lithium battery loss analysis device according to an embodiment of the present invention;

[0025] Figure 5 is a schematic diagram of an optional electronic device according to an embodiment of the present invention. DETAILED DESCRIPTION

[0026] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0027] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0028] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data for display, data for analysis, etc.) involved in this disclosure are all information and data authorized by the user or fully authorized by all parties.

[0029] Example 1

[0030] According to an embodiment of the present invention, an embodiment of a loss analysis method for a lithium battery is provided. It should be noted that the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions, and although a logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in an order different from that shown here.

[0031] Figure 1 is a schematic diagram of an optional loss analysis method of a lithium battery according to an embodiment of the present invention, such as Figure 1 As shown, the method comprises the following steps:

[0032] Step S101, obtaining discharge data of a lithium battery in N charge and discharge cycles, where N is a positive integer.

[0033] Optionally, electronic devices, application systems, servers and other devices may be used as the execution subject of the present application. In this embodiment, the target processing system is used as the execution subject to execute the above-mentioned lithium battery loss analysis method.

[0034] Optionally, the lithium battery to be analyzed for loss in this embodiment may be a lithium battery before it is manufactured. The N charge and discharge cycles mentioned above refer to charge and discharge cycles of the lithium battery according to the first charge and discharge method. The charge and discharge rate used in the first charge method is the target charge and discharge rate. For example, the target charge and discharge rate may be 0.2C. The lithium battery is charged and discharged at 0.2C for one week to obtain the discharge data of the lithium battery.

[0035] In some embodiments, the aforementioned N charge-discharge cycles are non-continuous N charge-discharge cycles. That is, any two of the aforementioned N charge-discharge cycles are separated by other charge-discharge cycles, and other charge-discharge cycles refer to charge-discharge cycles in which the lithium battery is charged and discharged using a non-first charge-discharge method. For example, other charge-discharge cycles refer to charge-discharge cycles in which the lithium battery is charged and discharged using a second charge-discharge method, and the second charge-discharge method is a charging method that meets the product specifications of the lithium battery.

[0036] Optionally, the discharge data of the lithium battery includes at least the discharge capacity value of the lithium battery during the discharge process. For example, during the discharge process, when the discharge time of the lithium battery reaches a preset time, the discharge capacity value of the lithium battery is collected, and the discharge capacity value is determined as the discharge data of the lithium battery. In this case, the discharge data only includes one discharge capacity value; for another example, during the discharge process, the discharge capacity value of the lithium battery is collected at a preset time interval (such as 30s) to obtain multiple discharge capacity values, and the multiple discharge capacity values ​​are determined as the discharge data of the lithium battery. In this case, the discharge data includes multiple discharge capacity values.

[0037] Step S102, based on the discharge data of each charge and discharge cycle, determining the maximum discharge capacity of the lithium battery in each charge and discharge cycle.

[0038] In some embodiments, for each of the N charge and discharge cycles, if the discharge capacity value in the discharge data corresponding to the charge and discharge cycle is collected when the discharge time of the lithium battery reaches a preset time, the discharge capacity value in the discharge data is determined as the maximum discharge capacity of the lithium battery in the charge and discharge cycle; if the discharge capacity value in the discharge data is collected according to a preset time interval, the maximum capacity value in the discharge data is determined as the maximum discharge capacity of the lithium battery in the charge and discharge cycle.

[0039] Step S103, for each of the N charge and discharge cycles, calculate the loss information of the lithium battery in the charge and discharge cycle according to the initial maximum discharge capacity of the initial charge and discharge cycle and the maximum discharge capacity of the charge and discharge cycle, wherein the loss information includes at least one of the following: active lithium loss ratio and active lithium loss mass.

[0040] In some embodiments, the initial maximum discharge capacity of the initial charge and discharge cycle may be a preset value.

[0041] In some embodiments, the initial maximum discharge capacity of the initial charge and discharge cycle can be determined based on the discharge data of the first charge and discharge cycle of the lithium battery. In this case, the method for determining the initial maximum discharge capacity is the same as the method for determining the maximum discharge capacity described above, so it is not repeated here.

[0042] Optionally, after determining the initial maximum discharge capacity, for each of the N charge and discharge cycles, the target processing system may calculate the loss information of the lithium battery in the charge and discharge cycle according to the initial maximum discharge capacity and the maximum discharge capacity of the charge and discharge cycle. For example, the capacity loss value is calculated according to the initial maximum discharge capacity and the maximum discharge capacity of the charge and discharge cycle, and then at least one of the active lithium loss ratio and the active lithium loss mass is calculated based on the capacity loss value.

[0043] Based on the scheme defined in the above steps S101 to S103, it can be known that in an embodiment of the present invention, the loss information of the lithium battery is calculated based on the maximum discharge capacity and the initial maximum discharge capacity of the lithium battery in the charge and discharge cycle, by obtaining the discharge data of the lithium battery in N charge and discharge cycles, and then obtaining the discharge data of the lithium battery in N charge and discharge cycles, so that for each charge and discharge cycle in the N charge and discharge cycles, according to the initial maximum discharge capacity of the initial charge and discharge cycle and the maximum discharge capacity of the charge and discharge cycle, the loss information of the lithium battery in the charge and discharge cycle is calculated. Wherein, N is a positive integer, and the loss information includes at least one of the following: active lithium loss ratio, active lithium loss mass.

[0044] It is easy to notice that in the above process, by obtaining the discharge data of the lithium battery in N charge and discharge cycles, and determining the maximum discharge capacity of the lithium battery in each charge and discharge cycle based on the discharge data of each charge and discharge cycle, the battery performance data of the lithium battery in the cycle process is effectively obtained, and by calculating the loss information of the lithium battery in the charge and discharge cycle according to the initial maximum discharge capacity of the initial charge and discharge cycle and the maximum discharge capacity of the charge and discharge cycle, the loss information of the lithium battery in the cycle process is calculated based on the attenuation of the lithium battery, thereby effectively improving the accuracy of the calculated loss information.

[0045] It can be seen that the solution provided in the present application achieves the purpose of calculating the loss information of the lithium battery based on the maximum discharge capacity and the initial maximum discharge capacity of the lithium battery during the charge and discharge cycle, thereby achieving the technical effect of improving the accuracy of the calculated loss information, and further solving the technical problem of low accuracy in analyzing the loss information of lithium batteries in the related art.

[0046] In an optional embodiment, in the process of obtaining discharge data of a lithium battery in N charge and discharge cycles, the target processing system may charge and discharge the lithium battery for one cycle according to a first charge and discharge method, and determine the discharge data in the cycle as the discharge data in N charge and discharge cycles, wherein the charge and discharge rate adopted by the first charge and discharge method is a target charge and discharge rate; charge and discharge the lithium battery for M cycles according to a second charge and discharge method, wherein the second charge and discharge method is a charging method that meets the product specifications of the lithium battery; and repeat the steps of charging and discharging the lithium battery for one cycle according to the first charge and discharge method, and charging and discharging the lithium battery for M cycles according to the second charge and discharge method until the discharge data of N charge and discharge cycles are obtained.

[0047] For example, assuming that N=5, M=49, and the target charge and discharge ratio is 0.2C, the process of obtaining the discharge data of the lithium battery in N charge and discharge cycles is exemplified. Optionally, the target processing system can charge and discharge the lithium battery for a certain number of weeks according to the product specification, and charge and discharge it for one week at 0.2C every 50 weeks, collect the charge and discharge data, and copy the discharge data of 0.2C every 50 weeks as the discharge data in 5 discharge cycles. For example, the lithium battery is first charged and discharged for one week at 0.2C (this week is counted as the 0th week), and the discharge data of the first charge and discharge cycle in the 5 charge and discharge cycles is collected in the process, and then the lithium battery is charged and discharged for 49 cycles according to the product specification, and then in the 50th cycle, the lithium battery is charged and discharged for one week at 0.2C, and the discharge data of the second charge and discharge cycle in the 5 charge and discharge cycles is collected in the process, and this is repeated continuously until the 200th week (when the lithium battery has actually been charged and discharged for 201 cycles) to obtain the discharge data of the lithium battery in the 5 charge and discharge cycles.

[0048] In some embodiments, during the discharge process of each charge and discharge cycle in the N charge and discharge cycles, the target processing system may collect the discharge capacity value of the lithium battery at a preset time interval (e.g., 30s), obtain multiple discharge capacity values, and determine the multiple discharge capacity values ​​as the discharge data of the lithium battery. In this case, the discharge data includes multiple discharge capacity values. For example, Table 1 shows an optional discharge data:

[0049] Table 1

[0050]

[0051]

[0052] As shown in Table 1, one column in Table 1 represents the charge and discharge data of one charge and discharge cycle.

[0053] In some embodiments, during the discharge process of each charge and discharge cycle in the N charge and discharge cycles, the target processing system may also collect the discharge capacity value and battery voltage of the lithium battery at a preset time interval (e.g., 30 seconds), and calculate the dV / dQ value based on the discharge capacity value and the battery voltage, thereby determining the collected discharge capacity value, battery voltage, and dV / dQ value as the discharge data of the lithium battery. For example, Table 2 shows an optional discharge data:

[0054] Table 2

[0055]

[0056] As shown in Table 2, each of the three columns (capacity, voltage, dV / dQ) in Table 2 represents the charge and discharge data of a charge and discharge cycle. Among them, dV / dQ represents the ratio between the voltage change of the lithium battery and the discharge capacity change of the lithium battery, dV / dQ=(V i -V i-1 ) / (Q i -Q i-1 ), V i , Q i Respectively represent the battery voltage and discharge capacity collected for the i-th time, V i-1 , Q i-1 They represent the battery voltage and discharge capacity collected for the i-1th time respectively.

[0057] Optionally, after calculating the dV / dQ at different time points corresponding to each charge and discharge cycle, the target processing system can generate a Q-dV / dQ curve for N charge and discharge cycles with the discharge capacity as the abscissa and dV / dQ as the ordinate, for example, Figure 2is a schematic diagram of an optional Q-dV / dQ curve according to an embodiment of the present invention, assuming that N charge and discharge cycles are the 0th cycle, the 50th cycle, the 100th cycle, the 150th cycle and the 200th cycle, Figure 2 The Q-dV / dQ curves of these five charge and discharge cycles are shown in FIG. Figure 2 The "cycles" in it is equivalent to indicating the period.

[0058] It should be noted that by charging and discharging the battery at a specific charge and discharge rate to obtain discharge data, it is possible to obtain battery discharge data under specific test conditions, which is conducive to more accurate measurement of the battery's electrochemical characteristics. By charging and discharging the battery according to product specifications, the charging and discharging of lithium batteries in actual use can be effectively simulated, so as to facilitate the evaluation of the performance of lithium batteries under daily use conditions and minimize the negative impact on battery life. By training and cycling the above process, changes in battery performance can be tracked for a long time, making it easier to detect rich loss information.

[0059] In an optional embodiment, before the initial maximum discharge capacity of the initial charge and discharge cycle and the maximum discharge capacity of the charge and discharge cycle, the target processing system may determine the first cycle of charge and discharge of the lithium battery as the initial charge and discharge cycle, wherein the first cycle adopts a first charge and discharge method to charge and discharge the lithium battery, and the charge and discharge rate adopted by the first charge and discharge method is the target charge and discharge rate.

[0060] In some embodiments, the target charge-discharge ratio is 0.2 C. In some embodiments, the initial charge-discharge cycle is equivalent to the 0th cycle of charge-discharge described above.

[0061] It should be noted that by charging and discharging the lithium battery for the first time using specific charge and discharge conditions, the original performance data of the lithium battery before it has undergone multiple charge and discharge cycles can be obtained, thereby facilitating improving the accuracy of determining the initial maximum discharge capacity.

[0062] In an optional embodiment, in the process of calculating the loss information of the lithium battery in the charge and discharge cycle based on the initial maximum discharge capacity of the initial charge and discharge cycle and the maximum discharge capacity of the charge and discharge cycle, the target processing system can calculate the difference between the initial maximum discharge capacity and the maximum discharge capacity of the charge and discharge cycle to obtain the capacity loss value corresponding to the charge and discharge cycle; and calculate the loss information of the lithium battery in the charge and discharge cycle based on the capacity loss value.

[0063] Optionally, the target processing system may subtract the maximum discharge capacity of the charge and discharge cycle from the initial maximum discharge capacity to obtain a capacity loss value.

[0064] In some embodiments, for each of the N charge-discharge cycles, Figure 2As shown in the box in, the capacity loss value corresponding to the charge and discharge cycle is equivalent to the offset distance of the end of the dV / dQ curve of the initial charge and discharge cycle relative to the end of the dV / dQ curve of the charge and discharge cycle toward the low capacity direction.

[0065] Optionally, after calculating the capacity loss value, the target processing system can calculate the loss information of the lithium battery during the charge and discharge cycle according to the capacity loss value. Among them, the capacity loss value is positively correlated with the active lithium loss ratio, and the capacity loss value is positively correlated with the active lithium loss mass.

[0066] It should be noted that, since the capacity loss value of a lithium battery is correlated with the loss of active lithium, the accuracy of the calculated loss information can be effectively improved by calculating the loss information of the lithium battery during the charge and discharge cycle based on the capacity loss value.

[0067] In an optional embodiment, when the loss information includes the loss mass of active lithium, in the process of calculating the loss information of the lithium battery during the charge and discharge cycle according to the capacity loss value, the target processing system can obtain the Faraday constant and the relative atomic mass of the lithium element; the active lithium loss mass is calculated based on the capacity loss value, the Faraday constant and the relative atomic mass of the lithium element, and the active lithium loss mass is determined as the loss information.

[0068] In some embodiments, the Faraday constant F = 96485.3399 C mol -1 , the relative atomic mass of lithium is M Li =6.94 g mol -1 .

[0069] After obtaining the Faraday constant and the relative atomic mass of the lithium element, the target processing system can calculate the active lithium loss mass based on the capacity loss value, the Faraday constant and the relative atomic mass of the lithium element, and determine the active lithium loss mass as loss information. Among them, the Faraday constant is negatively correlated with the active lithium loss mass, and the relative atomic mass of the lithium element is positively correlated with the active lithium loss mass.

[0070] It should be noted that, through the above method, the accurate calculation of the loss mass of active lithium is achieved, and the accuracy of the calculation of the loss information is improved.

[0071] In an optional embodiment, in the process of calculating the active lithium loss mass based on the capacity loss value, the Faraday constant and the relative atomic mass of the lithium element, the target processing system can calculate the ratio between the capacity loss value and the Faraday constant to obtain a first value; and calculate the product between the first value and the relative atomic mass of the lithium element to obtain the active lithium loss mass.

[0072] Optionally, the target processing system may calculate the first value according to the following formula:

[0073] n=ΔQ / F (1)

[0074] Here, ΔQ represents the capacity loss value, and n is equivalent to the first value.

[0075] Optionally, after obtaining the first value, the target processing system may determine the active lithium loss mass according to the first value and the relative atomic mass of the lithium element, wherein the relative atomic mass of the lithium element, the first value and the active lithium loss mass are positively correlated. For example, the first value and the relative atomic mass of the lithium element are multiplied to obtain the active lithium loss mass.

[0076] It should be noted that, through the above method, the accurate calculation of the loss mass of active lithium is achieved, and the accuracy of the calculation of the loss information is improved.

[0077] In an optional embodiment, in the process of determining the active lithium loss mass based on the first value and the relative atomic mass of the lithium element, the target processing system can calculate the product between the first value and the relative atomic mass of the lithium element to obtain the active lithium loss mass.

[0078] Optionally, the target processing system can calculate the active lithium loss mass according to the following formula:

[0079] m=n*MLi (2)

[0080] Wherein, m represents the loss mass of active lithium.

[0081] For example, assuming that the initial maximum discharge capacity is 4.3907 and the maximum discharge capacity in a certain charge and discharge cycle is 4.3397, the calculated capacity loss value 1 is 3.6683E-06g.

[0082] It should be noted that, through the above method, the accurate calculation of the loss mass of active lithium is achieved, and the accuracy of the calculation of the loss information is improved.

[0083] In an optional embodiment, when the loss information includes the active lithium loss ratio, in the process of calculating the loss information of the lithium battery during the charge and discharge cycle based on the capacity loss value, the target processing system can calculate the ratio between the capacity loss value and the initial maximum discharge capacity, obtain the active lithium loss ratio, and determine the active lithium loss ratio as the loss information.

[0084] Optionally, the target processing system can calculate the active lithium loss ratio according to the following formula:

[0085]

[0086] Among them, LLI% represents the proportion of active lithium loss, abs() is the absolute value calculation, max(Q0) represents the initial maximum discharge capacity, max(Q) represents the maximum discharge capacity, and abs(max(Q0))-abs(max(Q)) is equivalent to the capacity loss value.

[0087] For example, assuming that the initial maximum discharge capacity is 4.3907 and the maximum discharge capacity of a certain charge and discharge cycle is 4.3397, the calculated active lithium loss accounts for 1.16%.

[0088] It should be noted that, through the above method, the accurate calculation of the active lithium loss ratio is achieved, and the accuracy of the loss information calculation is improved.

[0089] In an optional embodiment, Figure 3 is a schematic diagram of optional loss information according to an embodiment of the present invention, such as Figure 3 As shown, Figure 3 The horizontal axis in is the number of battery charge and discharge cycles, wherein the lithium battery is charged and discharged once every 50 cycles according to the first charge and discharge method. Figure 3 The vertical axis on the left side is the percentage of active lithium loss. Figure 3 The vertical axis on the right side is the loss mass of active lithium. Figure 3 The figure shows the percentage of active lithium loss and the mass of active lithium loss during the cycle of lithium batteries.

[0090] It can be seen that the solution provided in the present application achieves the purpose of calculating the loss information of the lithium battery based on the maximum discharge capacity and the initial maximum discharge capacity of the lithium battery during the charge and discharge cycle, thereby achieving the technical effect of improving the accuracy of the calculated loss information, and further solving the technical problem of low accuracy in analyzing the loss information of lithium batteries in the related art.

[0091] Example 2

[0092] According to an embodiment of the present invention, an embodiment of a loss analysis device for a lithium battery is provided, wherein: Figure 4 is a schematic diagram of an optional lithium battery loss analysis device according to an embodiment of the present invention, such as Figure 4 As shown, the device comprises:

[0093] The acquisition module 401 is used to acquire the discharge data of the lithium battery in N charge and discharge cycles, where N is a positive integer;

[0094] A first determination module 402, configured to determine the maximum discharge capacity of the lithium battery in each charge and discharge cycle based on the discharge data of each charge and discharge cycle;

[0095] The calculation module 403 is used to calculate the loss information of the lithium battery in the charge and discharge cycle for each of the N charge and discharge cycles according to the initial maximum discharge capacity of the initial charge and discharge cycle and the maximum discharge capacity of the charge and discharge cycle, wherein the loss information includes at least one of the following: active lithium loss ratio and active lithium loss mass.

[0096] It should be noted that the acquisition module 401, the first determination module 402 and the calculation module 403 correspond to steps S101 to S103 in the above embodiment, and the examples and application scenarios implemented by the three modules and the corresponding steps are the same, but are not limited to the contents disclosed in the above embodiment 1.

[0097] Optionally, the acquisition module also includes: a determination submodule, used to charge and discharge the lithium battery for one cycle according to a first charge and discharge method, and determine the discharge data in the cycle as the discharge data in N charge and discharge cycles, wherein the charge and discharge rate adopted by the first charge and discharge method is a target charge and discharge rate; a charge and discharge electronic module, used to charge and discharge the lithium battery for M cycles according to a second charge and discharge method, wherein the second charge and discharge method is a charging method that meets the product specifications of the lithium battery; an execution submodule, used to repeatedly execute the steps of charging and discharging the lithium battery for one cycle according to the first charge and discharge method, and charging and discharging the lithium battery for M cycles according to the second charge and discharge method, until the discharge data of N charge and discharge cycles are obtained.

[0098] Optionally, the lithium battery loss analysis device also includes: a second determination module, used to determine the first cycle of charging and discharging the lithium battery as an initial charging and discharging cycle, wherein the first cycle uses a first charging and discharging method to charge and discharge the lithium battery, and the charging and discharging rate used by the first charging and discharging method is a target charging and discharging rate.

[0099] Optionally, the calculation module also includes: a first calculation submodule, used to calculate the difference between the initial maximum discharge capacity and the maximum discharge capacity of the charge and discharge cycle to obtain the capacity loss value corresponding to the charge and discharge cycle; and a second calculation submodule, used to calculate the loss information of the lithium battery during the charge and discharge cycle based on the capacity loss value.

[0100] Optionally, the second calculation submodule also includes: an acquisition unit, used to obtain the Faraday constant and the relative atomic mass of the lithium element; a first calculation unit, used to calculate the active lithium loss mass based on the capacity loss value, the Faraday constant and the relative atomic mass of the lithium element, and determine the active lithium loss mass as the loss information.

[0101] Optionally, the first calculation unit also includes: a first calculation subunit, used to calculate the ratio between the capacity loss value and the Faraday constant to obtain a first numerical value; and a second calculation subunit, used to determine the active lithium loss mass based on the first numerical value and the relative atomic mass of the lithium element.

[0102] Optionally, the second calculation subunit further includes: a third calculation subunit, configured to calculate the product of the first value and the relative atomic mass of the lithium element to obtain the active lithium loss mass.

[0103] Optionally, the second calculation submodule further includes: a second calculation unit, configured to calculate a ratio between the capacity loss value and the initial maximum discharge capacity to obtain an active lithium loss ratio, and determine the active lithium loss ratio as loss information.

[0104] Example 3

[0105] According to another aspect of an embodiment of the present invention, a computer-readable storage medium is further provided, in which a computer program is stored, wherein the computer program is configured to execute the above-mentioned lithium battery loss analysis method when running.

[0106] Example 4

[0107] According to another aspect of an embodiment of the present invention, there is also provided an electronic device, wherein: Figure 5 is a schematic diagram of an optional electronic device according to an embodiment of the present invention, such as Figure 5 As shown, the electronic device includes one or more processors; a memory for storing one or more programs, which, when the one or more programs are executed by the one or more processors, enables the one or more processors to run the programs, wherein the programs are configured to execute the above-mentioned lithium battery loss analysis method when running.

[0108] Optionally, the processor implements the following steps when executing the program: obtaining discharge data of the lithium battery in N charge and discharge cycles, where N is a positive integer; determining the maximum discharge capacity of the lithium battery in each charge and discharge cycle based on the discharge data of each charge and discharge cycle; for each of the N charge and discharge cycles, calculating the loss information of the lithium battery in the charge and discharge cycle based on the initial maximum discharge capacity of the initial charge and discharge cycle and the maximum discharge capacity of the charge and discharge cycle, wherein the loss information includes at least one of the following: the proportion of active lithium loss and the mass of active lithium loss.

[0109] Optionally, when executing the program, the processor also implements the following steps: charging and discharging the lithium battery for one cycle according to the first charging and discharging method, and determining the discharge data in the cycle as the discharge data in N charging and discharging cycles, wherein the charge and discharge rate adopted by the first charging and discharging method is the target charge and discharge rate; charging and discharging the lithium battery for M cycles according to the second charging and discharging method, wherein the second charging and discharging method is a charging method that meets the product specifications of the lithium battery; repeating the steps of charging and discharging the lithium battery for one cycle according to the first charging and discharging method, and charging and discharging the lithium battery for M cycles according to the second charging and discharging method until the discharge data of N charging and discharging cycles are obtained.

[0110] Optionally, the processor also implements the following steps when executing the program: before determining the first cycle of charging and discharging the lithium battery as the initial charging and discharging cycle based on the initial maximum discharge capacity of the initial charging and discharging cycle and the maximum discharge capacity of the charging and discharging cycle, wherein the first cycle uses a first charging and discharging method to charge and discharge the lithium battery, and the charging and discharging rate used by the first charging and discharging method is a target charging and discharging rate.

[0111] Optionally, when the processor executes the program, the following steps are also implemented: calculating the difference between the initial maximum discharge capacity and the maximum discharge capacity of the charge and discharge cycle to obtain the capacity loss value corresponding to the charge and discharge cycle; and calculating the loss information of the lithium battery during the charge and discharge cycle based on the capacity loss value.

[0112] Optionally, when the processor executes the program, the following steps are also implemented: obtaining the Faraday constant and the relative atomic mass of the lithium element; calculating the active lithium loss mass based on the capacity loss value, the Faraday constant and the relative atomic mass of the lithium element, and determining the active lithium loss mass as the loss information.

[0113] Optionally, when the processor executes the program, the following steps are also implemented: calculating the ratio between the capacity loss value and the Faraday constant to obtain a first value; calculating the product between the first value and the relative atomic mass of the lithium element to obtain the active lithium loss mass.

[0114] Optionally, when the processor executes the program, the following steps are further implemented: calculating the ratio between the capacity loss value and the initial maximum discharge capacity to obtain the active lithium loss ratio, and determining the active lithium loss ratio as the loss information.

[0115] Example 5

[0116] According to another aspect of an embodiment of the present invention, a computer program product is provided, including a computer program / instruction, and when the computer program / instruction is executed by a processor, the above-mentioned lithium battery loss analysis method is implemented.

[0117] The serial numbers of the above embodiments of the present invention are only for description and do not represent the advantages or disadvantages of the embodiments.

[0118] In the above embodiments of the present invention, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0119] In the several embodiments provided in this application, it should be understood that the disclosed technical content can be implemented in other ways. Among them, the device embodiments described above are only schematic. For example, the division of units can be a logical function division. There may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of units or modules, which can be electrical or other forms.

[0120] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed over multiple units. Some or all of the units may be selected according to actual needs to achieve the purpose of the present embodiment.

[0121] In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0122] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions for a computer device (which can be a personal computer, a server or a network device, etc.) to perform all or part of the steps of the methods of each embodiment of the present invention. The aforementioned storage medium includes: U disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), mobile hard disk, magnetic disk or optical disk and other media that can store program codes.

[0123] The above are only preferred embodiments of the present invention. It should be pointed out that, for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A loss analysis method for a lithium battery, characterized in that: include: Obtain discharge data of a lithium battery in N charge and discharge cycles, where N is a positive integer; Determining the maximum discharge capacity of the lithium battery in each charge and discharge cycle based on the discharge data of each charge and discharge cycle; For each of the N charge and discharge cycles, the loss information of the lithium battery in the charge and discharge cycle is calculated based on the initial maximum discharge capacity of the initial charge and discharge cycle and the maximum discharge capacity of the charge and discharge cycle, wherein the loss information includes at least one of the following: active lithium loss percentage and active lithium loss mass.

2. The method according to claim 1, characterized in that: Obtain the discharge data of the lithium battery in N charge and discharge cycles, including: Charge and discharge the lithium battery for one cycle according to a first charge and discharge method, and determine the discharge data in the cycle as the discharge data in the N charge and discharge cycles, wherein the charge and discharge rate adopted by the first charge and discharge method is a target charge and discharge rate; Charge and discharge the lithium battery for M cycles according to a second charge and discharge method, wherein the second charge and discharge method is a charging method that meets the product specification of the lithium battery; Repeat the steps of charging and discharging the lithium battery for one cycle according to the first charging and discharging method, and charging and discharging the lithium battery for M cycles according to the second charging and discharging method, until discharge data of the N charging and discharging cycles are obtained.

3. The method according to claim 1 or 2, characterized in that: Before the initial maximum discharge capacity of the initial charge-discharge cycle and the maximum discharge capacity of the charge-discharge cycle, the method further comprises: The first cycle of charging and discharging the lithium battery is determined as the initial charging and discharging cycle, wherein the first cycle uses a first charging and discharging method to charge and discharge the lithium battery, and the charging and discharging rate used by the first charging and discharging method is a target charging and discharging rate.

4. The method according to claim 1 or 2, characterized in that: Calculating the loss information of the lithium battery in the charge and discharge cycle according to the initial maximum discharge capacity of the initial charge and discharge cycle and the maximum discharge capacity of the charge and discharge cycle, including: Calculating the difference between the initial maximum discharge capacity and the maximum discharge capacity of the charge and discharge cycle to obtain a capacity loss value corresponding to the charge and discharge cycle; The loss information of the lithium battery during the charge and discharge cycle is calculated according to the capacity loss value.

5. The method according to claim 4, characterized in that In the case where the loss information includes the loss mass of the active lithium, calculating the loss information of the lithium battery during the charge and discharge cycle according to the capacity loss value includes: Obtain Faraday's constant and the relative atomic mass of lithium; The active lithium loss mass is calculated based on the capacity loss value, the Faraday constant and the relative atomic mass of the lithium element, and the active lithium loss mass is determined as the loss information.

6. The method according to claim 5, characterized in that The active lithium loss mass is calculated based on the capacity loss value, the Faraday constant and the relative atomic mass of the lithium element, comprising: Calculating a ratio between the capacity loss value and the Faraday constant to obtain a first value; The active lithium loss mass is determined according to the first value and the relative atomic mass of the lithium element.

7. The method according to claim 6, characterized in that Determining the active lithium loss mass according to the first value and the relative atomic mass of the lithium element includes: The product of the first value and the relative atomic mass of the lithium element is calculated to obtain the active lithium loss mass.

8. The method according to claim 4, characterized in that In the case where the loss information includes the active lithium loss ratio, calculating the loss information of the lithium battery during the charge and discharge cycle according to the capacity loss value includes: The ratio between the capacity loss value and the initial maximum discharge capacity is calculated to obtain the active lithium loss ratio, and the active lithium loss ratio is determined as the loss information.

9. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, wherein the computer program is configured to execute the loss analysis method for a lithium battery as claimed in any one of claims 1 to 8 when running.

10. An electronic device, characterized in that: The electronic device includes one or more processors; A memory for storing one or more programs, which, when executed by the one or more processors, enables the one or more processors to run the programs, wherein the program is configured to execute the loss analysis method for a lithium battery as described in any one of claims 1 to 8 when run.

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