Film-forming potential region calibration method, device, equipment, storage medium and program product

Abstract

The invention relates to a film-forming potential region calibration method and device, equipment, a storage medium and a program product. The method comprises the following steps: for each formation process in a plurality of formation processes of a battery, drawing an incremental capacity curve of the formation process according to the potential between a negative electrode and a reference electrode of the battery and the capacity corresponding to the potential in the formation process; determining an initial film forming potential region according to a first differential capacity peak of a first incremental capacity curve of a first formation process in the plurality of formation processes and a second differential capacity peak of a second incremental capacity curve of a non-first formation process in the plurality of formation processes; and determining a target film-forming potential region from the initial film-forming potential region according to the first differential capacity peak, so that the film-forming potential region of the battery cathode SEI film can be accurately calibrated based on incremental capacity curves of a plurality of formation processes, the film-forming process of the SEI film can be accurately controlled according to the accurate film-forming potential region, the components and the structure of the SEI film are optimized, and the battery cathode SEI film forming quality is improved. The performance and the service life of the battery are improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of potential calibration, and in particular to a film-forming potential region calibration method, device, equipment, storage medium and program product. BACKGROUND

[0002] In the first charge-discharge process of a lithium ion battery, the formation step is crucial, which directly determines the initial performance and subsequent cycle stability of the battery. During the formation process, a solid electrolyte interface (SEI) film is formed on the surface of the negative electrode of the lithium ion battery, which plays a key role in the electrochemical performance and safety of the lithium ion battery. Different film-forming reactions occur at different potentials during the formation process, and the products and proportions of these film-forming reactions directly affect the structure and performance of the SEI film.

[0003] However, there is currently a lack of calibration methods for the film-forming potential of the SEI film, resulting in unstable formation of the SEI film, which in turn affects the electrochemical performance of the lithium ion battery. SUMMARY

[0004] Therefore, it is necessary to provide a film-forming potential region calibration method, device, equipment, storage medium and program product capable of calibrating the film-forming potential of the SEI film in view of the above technical problems.

[0005] In a first aspect, the present application provides a film-forming potential region calibration method. The method comprises:

[0006] For each formation process in a plurality of formation processes of a battery, an incremental capacity curve of the formation process is plotted according to a potential between a negative electrode of the battery and a reference electrode in the formation process and a capacity corresponding to the potential;

[0007] An initial film-forming potential region is determined according to a first differential capacity peak of a first incremental capacity curve of a first formation process in the plurality of formation processes and a second differential capacity peak of a second incremental capacity curve of a non-first formation process in the plurality of formation processes;

[0008] A target film-forming potential region is determined from the initial film-forming potential region according to the first differential capacity peak.

[0009] In one embodiment, the initial film-forming potential region is determined according to the first differential capacity peak of the first incremental capacity curve of the first formation process in the plurality of formation processes and the second differential capacity peak of the second incremental capacity curve of the non-first formation process in the plurality of formation processes, comprising:

[0010] determining a first differential capacity peak and a second differential capacity peak corresponding to the first differential capacity peak; the second differential capacity peak corresponding to the first differential capacity peak has the same ordinal position on the second incremental capacity curve as the first differential capacity peak has on the first incremental capacity curve;

[0011] determining a first differential capacity peak with an area greater than the second differential capacity peak from the two differential capacity peaks; the two differential capacity peaks include the first differential capacity peak and the second differential capacity peak corresponding to the first differential capacity peak;

[0012] determining the initial film-forming potential region according to the first differential capacity peak with an area greater than the second differential capacity peak.

[0013] In one of the embodiments, the determining the initial film-forming potential region according to the first differential capacity peak with an area greater than the second differential capacity peak comprises:

[0014] determining a potential region corresponding to the first differential capacity peak with an area greater than the second differential capacity peak as the initial film-forming potential region.

[0015] In one of the embodiments, the determining the target film-forming potential region according to the first differential capacity peak from the initial film-forming potential region comprises:

[0016] determining a potential corresponding to the highest peak value of the first differential capacity peak of the initial film-forming potential region as a center film-forming potential;

[0017] determining the target film-forming potential region according to the center film-forming potential and a preset state of charge offset.

[0018] In one of the embodiments, the determining the target film-forming potential region according to the center film-forming potential comprises:

[0019] forming a state of charge interval corresponding to the center film-forming potential by offsetting in the charging direction and the discharging direction respectively according to the preset state of charge offset with the state of charge of the center film-forming potential as the origin.

[0020] In one of the embodiments, the method further comprises:

[0021] performing multiple formation on the battery based on a preset rate, or performing multiple standard formation on the battery to form multiple formation processes.

[0022] In a second aspect, the application further provides a film-forming potential region calibration device. The device comprises:

[0023] a drawing module configured to draw an incremental capacity curve of each formation process from multiple formation processes of a battery according to a potential between a negative electrode of the battery and a reference electrode in the formation process and a capacity corresponding to the potential.

[0024] The first determining module is configured to determine an initial film formation potential region according to a first differential capacity peak of a first incremental capacity curve of a first formation process in the plurality of formation processes and a second differential capacity peak of a second incremental capacity curve of a non-first formation process in the plurality of formation processes.

[0025] The second determining module is configured to determine a target film formation potential region from the initial film formation potential region according to the first differential capacity peak.

[0026] In a third aspect, a computer device is provided, which includes a memory and a processor. The memory stores a computer program. When the processor executes the computer program, the steps of any of the above methods are implemented.

[0027] In a fourth aspect, a computer readable storage medium is provided, which stores a computer program. When the computer program is executed by a processor, the steps of any of the above methods are implemented.

[0028] In a fifth aspect, a computer program product is provided, which includes a computer program. When the computer program is executed by a processor, the steps of any of the above methods are implemented.

[0029] The film formation potential region calibration method, device, equipment, storage medium and program product can determine an initial film formation potential region according to a first differential capacity peak of a first incremental capacity curve of a first formation process in the plurality of formation processes and a second differential capacity peak of a second incremental capacity curve of a non-first formation process in the plurality of formation processes, and determine a target film formation potential region from the initial film formation potential region according to the first differential capacity peak, so that the film formation potential region of the SEI film of the battery can be accurately calibrated based on the incremental capacity curves of the plurality of formation processes, the film formation process of the SEI film can be accurately controlled according to the accurate film formation potential region, the composition and structure of the SEI film can be optimized, and the performance and service life of the battery can be improved. BRIEF DESCRIPTION OF DRAWINGS

[0030] Figure 1 FIG. 1 is an internal structure diagram of a computer device provided by an embodiment of the present application;

[0031] Figure 2 FIG. 2 is a flowchart of a film formation potential region calibration method provided by an embodiment of the present application;

[0032] Figure 3 FIG. 3 is a structural schematic diagram of a battery provided by an embodiment of the present application;

[0033] Figure 4is a kind of incremental capacity graph provided by the embodiment of the application;

[0034] Figure 5 is another incremental capacity graph provided by the embodiment of the application;

[0035] Figure 6 is a flowchart of the initial film-forming potential region determination method provided by the embodiment of the application;

[0036] Figure 7 is a flowchart of the target film-forming potential region determination method provided by the embodiment of the application;

[0037] Figure 8 is a flowchart of the film-forming potential region calibration method of lithium ion battery negative electrode SEI film provided by the embodiment of the application;

[0038] Figure 9 is a structural block diagram of the film-forming potential region calibration device provided by the embodiment of the application. DETAILED DESCRIPTION

[0039] In order to make the purpose, technical scheme and advantages of the present application clearer, the present application will be further described in detail below in combination with the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and not to limit the present application.

[0040] In the first charge and discharge process of lithium ion battery, the formation step is crucial, which directly determines the initial performance and subsequent cycle stability of the battery. During the formation process, a layer of solid electrolyte interface (SEI) film will be formed on the surface of the lithium ion battery negative electrode, which plays a key role in the electrochemical performance and safety of the lithium ion battery. Different film-forming reactions occur at different potentials during the formation process, and the products and proportions of these film-forming reactions directly affect the structure and performance of the SEI film.

[0041] However, there is currently a lack of calibration method for the film-forming potential of SEI film, resulting in unstable formation of SEI film, which in turn affects the electrochemical performance of the battery.

[0042] The formation of SEI film is a complex electrochemical process, and its main components include inorganic substances (such as Li2O, LiF, etc.) and organic substances (such as alkyl lithium carbonate, etc.). Different film-forming reactions occur at different potentials during the formation process. For example, at a lower potential, solvent molecules in the electrolyte may undergo a reduction reaction to generate inorganic components; while at a higher potential, lithium ions may react with negative electrode materials to generate organic components. The products and proportions of these reactions directly affect the structure and performance of the SEI film.

[0043] However, there is currently no accurate calibration method for the film-forming potential of the SEI film. The existing formation process is mostly based on the potential range set by experience, and cannot accurately distinguish the start and end potential of different film-forming reactions. This inaccurate potential control leads to unstable growth of the SEI film, which in turn affects the performance consistency of the battery. For example, if the overall potential of the formation process is too high, it may cause too much organic component in the SEI film, increasing the internal resistance of the battery; if the overall potential of the formation process is too low, it may form a SEI film with too much inorganic component, causing the SEI film to crack.

[0044] The film-forming potential region calibration method provided by the embodiments of the present application can be applied in an application environment as shown in Figure 1 . Figure 1 is an internal structure diagram of a computer device provided by an embodiment of the present application. The computer device can be a server, and its internal structure diagram can be as shown in Figure 1 . The computer device includes a processor, a memory and a network interface connected through a system bus. The processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system, a computer program and a database. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The network interface of the computer device is used to communicate with external terminals through network connection. The computer program is executed by the processor to implement a film-forming potential region calibration method.

[0045] Those skilled in the art can understand that Figure 1 the structure shown in the figure is only a block diagram of part of the structure related to the scheme of the present application, and does not constitute a limitation on the computer device to which the scheme of the present application is applied. The specific computer device can include more or fewer components than those shown in the figure, or combine certain components, or have a different arrangement of components.

[0046] In one embodiment, as shown in Figure 2 , Figure 2 is a flowchart of a film-forming potential region calibration method provided by an embodiment of the present application. The method can be applied to a computer device in Figure 1 . The method includes the following steps:

[0047] S201, for each formation process of a plurality of formation processes of a battery, an incremental capacity curve of the formation process is plotted according to the potential between the negative electrode of the battery and the reference electrode in the formation process and the capacity corresponding to the potential.

[0048] Referring to Figure 3 , Figure 3is a structural schematic diagram of a battery provided by an embodiment of the present application. As shown in the example, Figure 3 The reference electrode can be implanted in the battery to be calibrated to decouple the positive and negative electrodes of the battery through the reference electrode.

[0049] In an embodiment of the present application, the well-soaked battery can be subjected to multiple cyclic formation or multiple formation based on a preset rate to form multiple cycles. Then, for each cycle, an incremental capacity curve of the capacity of the battery in the formation process versus the potential between the negative electrode and the reference electrode is plotted, i.e., an IC curve.

[0050] Referring to Figure 4 , Figure 4 is an incremental capacity curve provided by an embodiment of the present application. As shown in the example, if the battery is subjected to five cyclic formations, i.e., there are five cycles, the incremental capacity curve plotted for each cycle can be as shown in Figure 4 Figure 4 The V shown in the above figure is the potential between the negative electrode and the reference electrode, and dQ / dV is used to represent the capacity of the battery.

[0051] S202, determining an initial film formation potential region according to a first differential capacity peak of a first incremental capacity curve of a first formation process in the multiple formation processes and a second differential capacity peak of a second incremental capacity curve of a non-first formation process in the multiple formation processes.

[0052] In an embodiment of the present application, after obtaining the incremental capacity curves of the multiple formation processes, the variation characteristics of each incremental capacity curve can be analyzed, i.e., a first differential capacity peak of a first incremental capacity curve of a first formation process (i.e., the first cycle) and a second differential capacity peak of a second incremental capacity curve of a non-first formation process (i.e., a cycle subsequent to the first cycle) in the multiple formation processes are determined, then a second differential capacity peak corresponding to each first differential capacity peak is determined, and for each first differential capacity peak, the area of the first differential capacity peak and the area of the second differential capacity peak corresponding to the first differential capacity peak are compared. If the area of the first differential capacity peak is greater than the area of the second differential capacity peak corresponding to the first differential capacity peak, the potential region where the first differential capacity peak is located is determined as the initial film formation potential region. The differential capacity peak is dQ / dV peak, and the number of the initial film formation potential regions is not limited.

[0053] In an embodiment, the second differential capacity peak corresponding to the first differential capacity peak can be determined according to the order of the first differential capacity peak on the first incremental capacity curve and the order of the second differential capacity peak on the second incremental capacity curve.

[0054] ​For example, if there are three first differential capacity peaks arranged in sequence on the first incremental capacity curve and three second differential capacity peaks arranged in sequence on the second incremental capacity curve, the first first differential capacity peak on the first incremental capacity curve corresponds to the first second differential capacity peak on the second incremental capacity curve, the second first differential capacity peak on the first incremental capacity curve corresponds to the second second differential capacity peak on the second incremental capacity curve, and the third first differential capacity peak on the first incremental capacity curve corresponds to the third second differential capacity peak on the second incremental capacity curve.

[0055] In S203, the target film-forming potential region is determined from the initial film-forming potential region according to the first differential capacity peak.

[0056] Optionally, the potential of the highest peak value of the first differential capacity peak corresponding to the initial film-forming potential region can be determined as the center film-forming potential, and then the charge state of the center film-forming potential (SOC) is taken as the reference, and the center film-forming potential is expanded by a preset state of charge offset to the front and back of the center film-forming potential, to form the target film-forming potential region.

[0057] For example, if the preset state of charge offset is 3% SOC, the SOC interval formed by 3% SOC before and after the charge state of the center film-forming potential can be taken as the target film-forming potential region.

[0058] Optionally, the preset state of charge offset can be, for example, in the range of 3-5% SOC. It should be noted that the value range of the preset state of charge offset is only one possible implementation, and is not limited to the value of the preset state of charge offset only within 3-5% SOC. In actual application, the value of the preset state of charge offset can be adjusted adaptively according to the actual situation.

[0059] Referring to Figure 5 , Figure 5 is another incremental capacity curve diagram provided by the embodiments of the present application. For example, as shown in Figure 5 , in an embodiment, there are three first differential capacity peaks, i.e. Figure 5 1 peak, 2 peak and 3 peak shown in

[0060] In the embodiments of the present application, the potential between the negative electrode of the battery and the reference electrode and the capacity corresponding to the potential in the formation process are used to draw the incremental capacity curve of the formation process for each of the plurality of formation processes of the battery; the first differential capacity peak of the first incremental capacity curve of the first formation process in the plurality of formation processes and the second differential capacity peak of the second incremental capacity curve of the non-first formation process in the plurality of formation processes are used to determine the initial film formation potential region; and the target film formation potential region is determined from the initial film formation potential region based on the first differential capacity peak, so that the film formation potential region of the SEI film of the negative electrode of the battery can be accurately calibrated based on the incremental capacity curves of the plurality of formation processes, the film formation process of the SEI film can be accurately controlled according to the accurate film formation potential region, the composition and structure of the SEI film are optimized, and the performance and service life of the battery are improved.

[0061] Reference Figure 6 , Figure 6 is a flowchart of an initial film formation potential region determination method provided by the embodiments of the present application. The embodiments relate to a possible implementation of how to determine the initial film formation potential region based on the first differential capacity peak of the first incremental capacity curve of the first formation process in the plurality of formation processes and the second differential capacity peak of the second incremental capacity curve of the non-first formation process in the plurality of formation processes. Based on the above embodiments, S202 includes the following steps:

[0062] S601, determining the first differential capacity peak and the second differential capacity peak corresponding to the first differential capacity peak.

[0063] The order of the second differential capacity peak corresponding to the first differential capacity peak on the second incremental capacity curve is the same as the order of the first differential capacity peak on the first incremental capacity curve.

[0064] In one embodiment, the second differential capacity peak corresponding to the first differential capacity peak can be determined, for example, according to the order of the first differential capacity peak on the first incremental capacity curve and the order of the second differential capacity peak on the second incremental capacity curve.

[0065] For example, if there are three first differential capacity peaks arranged in sequence on the first incremental capacity curve and three second differential capacity peaks arranged in sequence on the second incremental capacity curve, the first first differential capacity peak on the first incremental capacity curve corresponds to the first second differential capacity peak on the second incremental capacity curve, the second first differential capacity peak on the first incremental capacity curve corresponds to the second second differential capacity peak on the second incremental capacity curve, and the third first differential capacity peak on the first incremental capacity curve corresponds to the third second differential capacity peak on the second incremental capacity curve.

[0066] S602, determining the first differential capacity peak with an area greater than the second differential capacity peak from the two differential capacity peaks.

[0067] The two differential capacity peaks include a first differential capacity peak and a second differential capacity peak corresponding to the first differential capacity peak.

[0068] In the embodiments of the present application, for each first differential capacity peak, the area of the first differential capacity peak and the area of the second differential capacity peak corresponding to the first differential capacity peak can be compared, and the first differential capacity peak with an area greater than the area of the corresponding second differential capacity peak can be determined.

[0069] S603, determining an initial film-forming potential region according to the first differential capacity peak with an area greater than the second differential capacity peak.

[0070] Alternatively, the potential region corresponding to the first differential capacity peak with an area greater than the second differential capacity peak can be directly determined as the initial film-forming potential region.

[0071] Alternatively, the first differential capacity peak with an area greater than the second differential capacity peak can be further screened, for example, for each first differential capacity peak with an area greater than the second differential capacity peak, the area deviation between the area of the first differential capacity peak and the area of the corresponding second differential capacity peak is determined, and the potential region corresponding to the first differential capacity peak with an area deviation greater than a preset deviation threshold is determined as the initial film-forming potential region.

[0072] In the embodiments of the present application, the first differential capacity peak and the second differential capacity peak corresponding to the first differential capacity peak are determined, the position of the second differential capacity peak corresponding to the first differential capacity peak on the second incremental capacity curve is the same as the position of the first differential capacity peak on the first incremental capacity curve, the first differential capacity peak with an area greater than the second differential capacity peak among the two differential capacity peaks is determined, the two differential capacity peaks include the first differential capacity peak and the second differential capacity peak corresponding to the first differential capacity peak, and the initial film-forming potential region is determined according to the first differential capacity peak with an area greater than the second differential capacity peak. Since the SEI film formed by the first cycle of the cycle formation process is irreversibly grown, the area of the differential capacity peak corresponding to the first cycle of the cycle formation process is greater than the area of the differential capacity peak corresponding to the subsequent cycle of the cycle formation process, so that the film-forming potential can be accurately calibrated based on this feature, and the film-forming process of the SEI film can be accurately controlled according to the accurate film-forming potential region, so as to optimize the composition and structure of the SEI film, and further improve the performance and life of the battery.

[0073] On the basis of the above-mentioned embodiments, the above-mentioned S603 specifically includes the following steps:

[0074] The potential region corresponding to the first differential capacity peak with an area greater than the second differential capacity peak is determined as the initial film-forming potential region.

[0075] In the embodiment of the present application, the potential region corresponding to the first differential capacity peak with an area larger than that of the second differential capacity peak is directly taken as the initial film-forming potential region, so that the film-forming potential can be accurately calibrated based on the characteristics of the irreversible growth of the SEI film in the cyclic chemical formation process, and the film-forming process of the SEI film can be accurately controlled according to the accurate film-forming potential region, so as to optimize the composition and structure of the SEI film, and further improve the performance and life of the battery.

[0076] With reference to Figure 7 , Figure 7 is a flowchart of a target film-forming potential region determination method provided by the embodiment of the present application. The embodiment relates to a possible implementation manner of how to determine a target film-forming potential region from an initial film-forming potential region according to a first differential capacity peak. On the basis of the above embodiment, S203 includes the following steps:

[0077] S701, determining the potential corresponding to the highest peak value of the first differential capacity peak of the initial film-forming potential region as the center film-forming potential.

[0078] In the embodiment of the present application, the potential corresponding to the highest peak value of the first differential capacity peak of the initial film-forming potential region can be determined as the center film-forming potential, that is, the potential with the largest difference in peak height of the dQ / dV peak is determined as the center film-forming potential.

[0079] S702, determining the target film-forming potential region according to the center film-forming potential and a preset state of charge offset.

[0080] Optionally, the state of charge of the center film-forming potential can be taken as a reference, and the state of charge (SOC) of the center film-forming potential is expanded by a preset state of charge offset before and after the center film-forming potential to form the target film-forming potential region.

[0081] For example, if the preset state of charge offset is 3% SOC, the state of charge interval formed by the state of charge of the center film-forming potential and the state of charge of the center film-forming potential before and after the center film-forming potential by 3% SOC can be taken as the target film-forming potential region.

[0082] Optionally, the value of the preset state of charge offset may, for example, be in the range of 3-5% SOC. It should be noted that the value range of the preset state of charge offset is only one possible implementation manner, and the value of the preset state of charge offset can only be in the range of 3-5% SOC. In actual application, the value of the preset state of charge offset can be adaptively adjusted according to actual conditions.

[0083] In the embodiments of the present application, the potential corresponding to the highest peak value of the first differential capacity peak in the initial film-forming potential region is determined as the center film-forming potential; and the target film-forming potential region is determined according to the center film-forming potential and the preset state of charge offset, so that the film-forming potential region of the battery negative electrode SEI film can be accurately calibrated based on the incremental capacity curves of multiple formation processes, and the film-forming process of the SEI film can be accurately controlled according to the accurate film-forming potential region, so as to optimize the composition and structure of the SEI film, and further improve the performance and life of the battery.

[0084] On the basis of the above-mentioned embodiments, the S702 specifically comprises the following steps:

[0085] Taking the state of charge of the center film-forming potential as the origin, the state of charge interval corresponding to the center film-forming potential is formed by offsetting in the charging direction and discharging direction according to the preset state of charge offset.

[0086] For example, taking the state of charge of the center film-forming potential as the reference, the target film-forming potential region is formed by extending the state of charge (SOC) of the center film-forming potential in the charging direction and discharging direction by the preset state of charge offset.

[0087] For example, if the preset state of charge offset is 3% SOC, the SOC interval formed by the state of charge of the center film-forming potential along the charging direction and discharging direction by 3% SOC can be taken as the target film-forming potential region.

[0088] Optionally, the value of the preset state of charge offset may, for example, be in the range of 3-5% SOC. It should be noted that the value range of the preset state of charge offset is only one possible implementation, and is not limited to the value of the preset state of charge offset being only within 3-5% SOC. In actual application, the value of the preset state of charge offset can be adaptively adjusted according to actual conditions.

[0089] In the embodiments of the present application, taking the state of charge of the center film-forming potential as the origin, the state of charge interval corresponding to the center film-forming potential is formed by offsetting in the charging direction and discharging direction according to the preset state of charge offset, so that the film-forming potential region of the battery negative electrode SEI film can be accurately calibrated based on the incremental capacity curves of multiple formation processes, and the film-forming process of the SEI film can be accurately controlled according to the accurate film-forming potential region, so as to optimize the composition and structure of the SEI film, and further improve the performance and life of the battery.

[0090] On the basis of the above-mentioned embodiments, the method further comprises the following steps:

[0091] The battery is subjected to multiple formation or multiple standard formation to form multiple formation processes.

[0092] In the embodiments of the present application, the infiltrated battery can be subjected to multiple cyclic standardization formation or multiple cyclic formation based on a preset rate, to form multiple cycles. The preset rate may, for example, be 0.1C, 0.2C, etc.

[0093] It should be noted that the value of the preset rate is not specifically limited in the embodiments of the present application, and the value of the preset rate mentioned above is only an exemplary embodiment, that is, the preset rate can be a fixed rate or a variable rate, and the value of the preset rate can be adaptively selected according to actual needs.

[0094] Referring to Figure 8 , Figure 8 is a flowchart of a method for marking a film formation potential region of a lithium ion battery negative electrode SEI film provided by the embodiments of the present application. The method comprises the following steps:

[0095] S801, performing multiple formation on the battery based on a preset rate, or performing multiple standardization formation on the battery, to form multiple formation processes.

[0096] S802, for each formation process in the multiple formation processes of the battery, an incremental capacity curve of the formation process is plotted according to the potential between the negative electrode of the battery and the reference electrode in the formation process and the capacity corresponding to the potential.

[0097] S803, determining a first differential capacity peak of a first incremental capacity curve of a first formation process in the multiple formation processes, and a second differential capacity peak of a second incremental capacity curve of a non-first formation process in the multiple formation processes corresponding to the first differential capacity peak.

[0098] S804, determining the potential region corresponding to the first differential capacity peak with an area greater than the second differential capacity peak as an initial film formation potential region.

[0099] S805, determining the potential corresponding to the highest peak value of the first differential capacity peak of the initial film formation potential region as a center film formation potential.

[0100] S806, taking the state of charge of the center film formation potential as the origin, offsetting in the charging direction and discharging direction according to a preset state of charge offset, to form a state of charge interval corresponding to the center film formation potential.

[0101] It should be understood that although the steps in the flowcharts involved in the embodiments described above are shown in sequence according to the arrows, the steps are not necessarily executed in the order indicated by the arrows. Unless otherwise specified herein, the execution of the steps is not strictly limited in sequence, and the steps can be executed in other sequences. Moreover, at least some of the steps in the flowcharts involved in the embodiments described above can include multiple steps or multiple stages, which are not necessarily executed at the same time but can be executed at different times, and the execution of the steps or stages is not necessarily sequential but can be executed alternately or in rotation with at least some of the other steps or the steps or stages in the other steps.

[0102] Based on the same inventive concept, the embodiments of the present application also provide a film-forming potential region calibration device for implementing the film-forming potential region calibration method described above. The implementation scheme for solving the problem provided by the device is similar to the implementation scheme described in the above method, so the specific limitations in one or more film-forming potential region calibration device embodiments provided below can refer to the limitations of the film-forming potential region calibration method described above, which will not be repeated here.

[0103] In one embodiment, as shown in Figure 9 , Figure 9 is a structural block diagram of a film-forming potential region calibration device provided by the embodiments of the present application. The device 900 includes:

[0104] The drawing module 901 is configured to, for each formation process in a plurality of formation processes of a battery, draw an incremental capacity curve of the formation process according to a potential between a negative electrode of the battery and a reference electrode in the formation process and a capacity corresponding to the potential.

[0105] The first determination module 902 is configured to determine an initial film-forming potential region according to a first differential capacity peak of a first incremental capacity curve of a first formation process in the plurality of formation processes and a second differential capacity peak of a second incremental capacity curve of a non-first formation process in the plurality of formation processes.

[0106] The second determination module 903 is configured to determine a target film-forming potential region from the initial film-forming potential region according to the first differential capacity peak.

[0107] In one embodiment, the first determination module 902 includes:

[0108] The first determination unit is configured to determine the first differential capacity peak and a second differential capacity peak corresponding to the first differential capacity peak, and the second differential capacity peak corresponding to the first differential capacity peak has the same position in the second incremental capacity curve as the first differential capacity peak in the first incremental capacity curve.

[0109] The second determining unit is configured to determine a first differential capacity peak with an area greater than a second differential capacity peak from two differential capacity peaks, the two differential capacity peaks including the first differential capacity peak and the second differential capacity peak corresponding to the first differential capacity peak.

[0110] The third determining unit is configured to determine an initial film-forming potential region according to the first differential capacity peak with the area greater than the second differential capacity peak.

[0111] In one of the embodiments, the third determining unit is specifically configured to determine a potential region corresponding to the first differential capacity peak with the area greater than the second differential capacity peak as the initial film-forming potential region.

[0112] In one of the embodiments, the second determining module 903 includes:

[0113] The fourth determining unit is configured to determine a potential corresponding to a highest peak value of the first differential capacity peak in the initial film-forming potential region as a center film-forming potential.

[0114] The fifth determining unit is configured to determine a target film-forming potential region according to the center film-forming potential and a preset state of charge offset.

[0115] In one of the embodiments, the fifth determining unit is specifically configured to take a state of charge of the center film-forming potential as a reference point, offset in a charging direction and a discharging direction according to the preset state of charge offset, to form a state of charge interval corresponding to the center film-forming potential.

[0116] In one of the embodiments, the apparatus 900 further includes:

[0117] The formation module is configured to perform multiple formations on the battery based on a preset rate, or perform multiple standard formations on the battery, to form multiple formation processes.

[0118] The above modules in the film-forming potential region calibration apparatus can be realized by software, hardware, or a combination thereof, in whole or in part. The above modules can be embedded in or independent of a processor in a computer device in hardware form, or stored in a memory in a computer device in software form, so as to be called and executed by a processor to perform operations corresponding to the above modules.

[0119] In one of the embodiments, a computer device is provided, including a memory and a processor, the memory storing a computer program, and the processor executing the computer program to implement the following steps:

[0120] For each formation process in multiple formation processes of the battery, an incremental capacity curve of the formation process is drawn according to a potential between a negative electrode of the battery and a reference electrode in the formation process and a capacity corresponding to the potential.

[0121] determine the initial film-forming potential region according to a first differential capacity peak of a first incremental capacity curve of a first forming process in the plurality of forming processes and a second differential capacity peak of a second incremental capacity curve of a non-first forming process in the plurality of forming processes;

[0122] determine the target film-forming potential region from the initial film-forming potential region according to the first differential capacity peak.

[0123] In one embodiment, the processor, when executing the computer program, further implements the following steps:

[0124] determine the first differential capacity peak and a second differential capacity peak corresponding to the first differential capacity peak; the order of the second differential capacity peak on the second incremental capacity curve is the same as the order of the first differential capacity peak on the first incremental capacity curve;

[0125] determine the first differential capacity peak with an area greater than the second differential capacity peak in the two differential capacity peaks; the two differential capacity peaks include the first differential capacity peak and the second differential capacity peak corresponding to the first differential capacity peak;

[0126] determine the initial film-forming potential region according to the first differential capacity peak with the area greater than the second differential capacity peak.

[0127] In one embodiment, the processor, when executing the computer program, further implements the following steps:

[0128] determine the initial film-forming potential region as a potential region corresponding to the first differential capacity peak with the area greater than the second differential capacity peak.

[0129] In one embodiment, the processor, when executing the computer program, further implements the following steps:

[0130] determine the center film-forming potential as a potential corresponding to a highest peak value of the first differential capacity peak of the initial film-forming potential region;

[0131] determine the target film-forming potential region according to the center film-forming potential and a preset state of charge offset.

[0132] In one embodiment, the processor, when executing the computer program, further implements the following steps:

[0133] shift the state of charge of the center film-forming potential in the charging direction and the discharging direction respectively according to the preset state of charge offset, to form a state of charge interval corresponding to the center film-forming potential.

[0134] In one embodiment, the processor, when executing the computer program, further implements the following steps:

[0135] perform multiple forming on the battery based on a preset rate, or perform multiple standard forming on the battery, to form the plurality of forming processes.

[0136] In one embodiment, a computer readable storage medium is provided, having stored thereon a computer program which, when executed by a processor, implements the following steps:

[0137] For each of a plurality of formation processes of a battery, an incremental capacity curve of the formation process is plotted according to a potential between a negative electrode of the battery and a reference electrode in the formation process and a capacity corresponding to the potential;

[0138] An initial film formation potential region is determined according to a first differential capacity peak of a first incremental capacity curve of a first formation process in the plurality of formation processes and a second differential capacity peak of a second incremental capacity curve of a non-first formation process in the plurality of formation processes;

[0139] A target film formation potential region is determined from the initial film formation potential region according to the first differential capacity peak.

[0140] In one embodiment, the computer program, when executed by the processor, further implements the following steps:

[0141] A first differential capacity peak and a second differential capacity peak corresponding to the first differential capacity peak are determined; the second differential capacity peak has a same order on the second incremental capacity curve as the first differential capacity peak has on the first incremental capacity curve;

[0142] A first differential capacity peak having an area greater than the second differential capacity peak is determined from the two differential capacity peaks; the two differential capacity peaks include the first differential capacity peak and the second differential capacity peak corresponding to the first differential capacity peak;

[0143] The initial film formation potential region is determined according to the first differential capacity peak having the area greater than the second differential capacity peak.

[0144] In one embodiment, the computer program, when executed by the processor, further implements the following steps:

[0145] A potential region corresponding to the first differential capacity peak having the area greater than the second differential capacity peak is determined as the initial film formation potential region.

[0146] In one embodiment, the computer program, when executed by the processor, further implements the following steps:

[0147] A highest peak value of the first differential capacity peak of the initial film formation potential region is determined as a center film formation potential;

[0148] The target film formation potential region is determined according to the center film formation potential and a preset state of charge offset.

[0149] In one embodiment, the computer program, when executed by the processor, further implements the following steps:

[0150] Taking the charge state of the center film-forming potential as the origin, offsetting in the charging direction and the discharging direction according to a preset charge state offset amount to form a charge state interval corresponding to the center film-forming potential.

[0151] In one embodiment, the computer program, when executed by the processor, further implements the following steps:

[0152] Based on the preset rate, the battery is subjected to multiple formation, or the battery is subjected to multiple standard formation to form multiple formation processes.

[0153] In one embodiment, a computer program product is provided, comprising a computer program which, when executed by the processor, implements the following steps:

[0154] For each formation process in the multiple formation processes of the battery, an incremental capacity curve of the formation process is plotted according to the potential between the negative electrode of the battery and the reference electrode in the formation process and the capacity corresponding to the potential.

[0155] According to a first differential capacity peak of a first incremental capacity curve of a first formation process in the multiple formation processes and a second differential capacity peak of a second incremental capacity curve of a non-first formation process in the multiple formation processes, an initial film-forming potential region is determined.

[0156] According to the first differential capacity peak, a target film-forming potential region is determined from the initial film-forming potential region.

[0157] In one embodiment, the computer program, when executed by the processor, further implements the following steps:

[0158] A first differential capacity peak and a second differential capacity peak corresponding to the first differential capacity peak are determined; the order of the second differential capacity peak on the second incremental capacity curve is the same as the order of the first differential capacity peak on the first incremental capacity curve.

[0159] A first differential capacity peak with an area greater than the second differential capacity peak is determined from the two differential capacity peaks; the two differential capacity peaks include the first differential capacity peak and the second differential capacity peak corresponding to the first differential capacity peak.

[0160] According to the first differential capacity peak with an area greater than the second differential capacity peak, an initial film-forming potential region is determined.

[0161] In one embodiment, the computer program, when executed by the processor, further implements the following steps:

[0162] A potential region corresponding to the first differential capacity peak with an area greater than the second differential capacity peak is determined as the initial film-forming potential region.

[0163] In one embodiment, the computer program, when executed by the processor, further implements the following steps:

[0164] The potential corresponding to the highest peak value of the first differential capacity peak of the initial film-forming potential region is determined as the center film-forming potential;

[0165] The target film-forming potential region is determined according to the center film-forming potential and the preset state of charge offset.

[0166] In one embodiment, the computer program, when executed by the processor, further implements the following steps:

[0167] With the state of charge of the center film-forming potential as the origin, the preset state of charge offset is offset in the charging direction and the discharging direction respectively to form the state of charge interval corresponding to the center film-forming potential.

[0168] In one embodiment, the computer program, when executed by the processor, further implements the following steps:

[0169] Based on the preset rate, the battery is subjected to multiple formation, or the battery is subjected to multiple standard formation to form multiple formation processes.

[0170] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program. The computer program can be stored in a non-volatile computer readable storage medium, and when the computer program is executed, the processes of the above-mentioned embodiments of the methods can be included. Any reference to memory, database or other medium used in the embodiments provided in the present application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical storage, high-density embedded non-volatile memory, resistive memory (ReRAM), magnetoresistive random access memory (MRAM), ferroelectric memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. As an illustration but not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM), etc. The database involved in the embodiments provided in the present application can include at least one of a relational database and a non-relational database. The non-relational database can include a distributed database based on a block chain, etc., without being limited thereto. The processor involved in the embodiments provided in the present application can be a general-purpose processor, a central processing unit, a graphics processing unit, a digital signal processor, a programmable logic device, a data processing logic device based on quantum computing, etc., without being limited thereto.

[0171] Any combination of the technical features of the above embodiments can be made. In order to make the description simple, all possible combinations of the technical features in the above embodiments are not described, however, as long as the combination of the technical features does not exist, it should be considered as the scope of the present application.

[0172] The above embodiments only express several implementation manners of the present application, and the description is more specific and detailed, but it should not be understood as a limitation on the scope of the patent of the present application. It should be pointed out that for ordinary skilled in the art, without departing from the concept of the present application, a number of modifications and improvements can be made, which are within the scope of protection of the present application. Therefore, the protection scope of the present application should be subject to the appended claims.

Claims

1. A method for calibrating a film forming potential region, characterized by, The method comprises: drawing, for each of a plurality of formation processes of a battery, an incremental capacity curve of the formation process according to a potential between a negative electrode of the battery and a reference electrode in the formation process and a capacity corresponding to the potential; determining an initial film formation potential region according to a first differential capacity peak of a first incremental capacity curve of a first formation process in the plurality of formation processes and a second differential capacity peak of a second incremental capacity curve of a non-first formation process in the plurality of formation processes. determining a target film formation potential region from the initial film formation potential region according to the first differential capacity peak.

2. The method of claim 1, wherein, The determining of the initial film formation potential region according to the first differential capacity peak of the first incremental capacity curve of the first formation process in the plurality of formation processes and the second differential capacity peak of the second incremental capacity curve of the non-first formation process in the plurality of formation processes comprises: determining a first differential capacity peak and a second differential capacity peak corresponding to the first differential capacity peak; the second differential capacity peak has a same position on the second incremental capacity curve as the first differential capacity peak on the first incremental capacity curve; determining a first differential capacity peak with an area greater than the second differential capacity peak from two differential capacity peaks; the two differential capacity peaks comprise the first differential capacity peak and the second differential capacity peak corresponding to the first differential capacity peak; determining the initial film formation potential region according to the first differential capacity peak with the area greater than the second differential capacity peak.

3. The method of claim 2, wherein, The determining of the initial film formation potential region according to the first differential capacity peak with the area greater than the second differential capacity peak comprises: determining, as the initial film formation potential region, a potential region corresponding to the first differential capacity peak with the area greater than the second differential capacity peak.

4. The method of claim 1, wherein, The determining of the target film formation potential region from the initial film formation potential region according to the first differential capacity peak comprises: determining, as a center film formation potential, a potential corresponding to a highest peak value of the first differential capacity peak of the initial film formation potential region; determining the target film formation potential region according to the center film formation potential and a preset state of charge offset.

5. The method of claim 4, wherein, The determining of the target film formation potential region according to the center film formation potential comprises: taking a state of charge of the center film formation potential as an origin, offsetting in a charging direction and a discharging direction respectively according to the preset state of charge offset, forming a state of charge interval corresponding to the center film formation potential, and taking the state of charge interval as the target film formation potential region.

6. The method according to any one of claims 1 to 5, characterized in that, The method further comprises: carrying out a plurality of formations on the battery based on a preset rate, or carrying out a plurality of standard formations on the battery to form the plurality of formation processes.

7. A film-forming potential region calibration device, characterized by comprising: The device comprises: a drawing module configured to draw, for each of a plurality of formation processes of a battery, an incremental capacity curve of the formation process according to a potential between a negative electrode of the battery and a reference electrode in the formation process and a capacity corresponding to the potential; The first determining module is configured to determine an initial film-forming potential region according to a first differential capacity peak of a first incremental capacity curve of a first formation process in the plurality of formation processes and a second differential capacity peak of a second incremental capacity curve of a non-first formation process in the plurality of formation processes. The second determining module is configured to determine a target film-forming potential region from the initial film-forming potential region according to the first differential capacity peak.

8. A computer device comprising a memory and a processor, the memory storing a computer program, characterized in that, The computer program is executed by the processor to implement the steps of the method in any one of claims 1 to 6.

9. A computer-readable storage medium having stored thereon a computer program, characterized in that, The computer program is executed by the processor to implement the steps of the method in any one of claims 1 to 6.

10. A computer program product comprising a computer program, characterized in that, The computer program is executed by the processor to implement the steps of the method in any one of claims 1 to 6.

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