Battery cell design method and system, battery cell, electronic equipment and storage medium

Abstract

The invention discloses a battery cell design method and system, a battery cell, electronic equipment and a storage medium. According to the method, the temperature difference of pole pieces at different positions in the battery cell can be reduced, and the safety of the battery cell is improved. The method comprises the following steps: acquiring a temperature value of each pole piece in a to-be-improved battery cell; determining the temperature difference between the temperature value of each pole piece and the reference temperature value; looking up a table according to the temperature difference between the temperature value of each pole piece and the reference temperature value so as to determine the design resistance of each pole piece; determining a difference value between the design resistance and the original resistance of each pole piece; the first corresponding relation table is inquired according to the difference value between the design resistance and the original resistance of each pole piece so as to determine the resistance adjusting strategy of each pole piece, and the resistance adjusting strategy is used for adjusting the resistance of each pole piece from the original resistance to the design resistance. By adopting the scheme provided by the invention, the temperature difference of the pole pieces at different positions in the battery cell is reduced, and the safety of the battery cell is improved.

Description

Technical Field

[0001] The present application relates to the technical field of vehicle battery cell research and development, and in particular to a battery cell design method, system, battery cell, electronic device and storage medium. Background Art

[0002] As requirements for battery cell charging capacity and energy density continue to increase, battery cell charging current capacity is getting higher and higher, and battery cell size design is getting larger and larger. This can lead to high heat generation and insufficient heat dissipation in the battery cells. Due to the different heat dissipation environments of the battery cell pole pieces, the heat conducts faster near the battery cell shell and the temperature is lower, while the temperature is higher near the center. As a result, within a single battery cell, there are large temperature differences between the battery cell pole pieces in different positions, and the temperature difference can even be as high as 10°C, affecting the accuracy of the battery cell temperature sampling.

[0003] Low accuracy in cell temperature sampling may result in the inability to detect very high temperatures, and as a result, the cell operation cannot be shut down in time when the temperature reaches the requirement for forced shutdown of the cell operation. It will also affect the formulation of the cell heat dissipation strategy. It can be seen that large temperature differences at different positions of the cell electrode will reduce the safety of the cell. Summary of the Invention

[0004] The present application provides a battery cell design method, system, battery cell, electronic device and storage medium to reduce the temperature difference of electrodes at different positions in the battery cell and improve the safety of the battery cell.

[0005] This application provides a battery cell design method, including:

[0006] Obtain the temperature value of each electrode in the battery cell to be improved;

[0007] Determine the temperature difference between the temperature value of each electrode and the reference temperature value;

[0008] A table is looked up based on the temperature difference between the temperature value of each electrode and the reference temperature value to determine the design resistance of each electrode, wherein after the resistance of each electrode is adjusted to the design resistance, the temperature difference between the temperature value of each electrode and the reference temperature value is less than a first difference;

[0009] Determine the difference between the designed resistance and the original resistance of each electrode;

[0010] The first correspondence table is queried based on the difference between the designed resistance and the original resistance of each electrode to determine the resistance adjustment strategy of each electrode, wherein the first correspondence table contains the correspondence between the resistance difference and the adjustment strategy, and the resistance adjustment strategy is used to adjust the resistance of each electrode from the original resistance to the designed resistance.

[0011] The beneficial effects of the present application are that: a table can be looked up based on the temperature difference between the temperature value of each electrode and the reference temperature value to determine the design resistance of each electrode, wherein, after the resistance of each electrode is adjusted to the design resistance, the temperature difference between the temperature value of each electrode and the reference temperature value is less than a first difference; the resistance adjustment strategy of each electrode is determined by the difference between the design resistance and the original resistance of each electrode, which is used to adjust the resistance of each electrode from the original resistance to the design resistance, so that the resistance of each electrode is adjusted to the design resistance through this scheme, and then the temperature difference between the temperature value of each electrode and the reference temperature value is less than the first difference, thereby reducing the temperature difference of electrodes at different positions in the battery cell and improving the safety of the battery cell.

[0012] In one embodiment, obtaining the temperature value of each electrode in the battery cell to be improved includes:

[0013] Charge the battery cells to be improved;

[0014] When the charging time of the battery cell to be improved reaches a preset time, the temperature value of each electrode in the battery cell to be improved is obtained by temperature sensors arranged at various positions in the battery cell to be improved.

[0015] In one embodiment, determining the temperature difference between the temperature value of each electrode and the reference temperature value includes:

[0016] Obtain the temperature value of the outermost electrode or the pre-stored temperature value;

[0017] Determine the temperature value of the outermost electrode or the pre-stored temperature value as the reference temperature value;

[0018] The temperature difference between the temperature value of each electrode and the reference temperature value is calculated.

[0019] In one embodiment, the step of looking up a table based on the temperature difference between the temperature value of each electrode and the reference temperature value to determine the design resistance of each electrode includes:

[0020] querying a second correspondence table according to the temperature difference between the temperature value of each electrode and the reference temperature value to determine the impedance difference between each electrode and the reference resistor, wherein the reference temperature value corresponds to the reference resistor, and the second correspondence table is used to record the correspondence between the temperature difference and the impedance difference;

[0021] The difference between the original resistance of each electrode piece and the impedance difference between each electrode piece and the reference resistance is determined as the design resistance of each electrode piece.

[0022] In one embodiment, querying a first correspondence table based on the difference between the designed resistance and the original resistance of each electrode piece to determine the resistance adjustment strategy of each electrode piece includes:

[0023] When the difference between the designed resistance and the original resistance of each electrode piece is positive, determining the resistance adjustment strategy of each electrode piece includes at least one of the following adjustment strategies:

[0024] Increasing the coating surface thickness, increasing the coating surface density, increasing the compaction density of the resistor material, and replacing the original resistor with a first resistor, wherein the resistance of the first resistor is greater than the resistance of the original resistor;

[0025] When the difference between the designed resistance and the original resistance of each electrode is negative, determining the resistance adjustment strategy of each electrode includes reducing the coating surface thickness or replacing the original resistor with a second resistor, wherein the resistance of the second resistor is smaller than the resistance of the original resistor.

[0026] In one embodiment, when the difference between the designed resistance and the original resistance of each electrode piece is positive, the method further includes:

[0027] When the difference between the original resistance and the designed resistance of the first target electrode piece is less than the second difference, determining that the resistance adjustment strategy for the first target electrode piece is to increase the compaction density of the resistance material;

[0028] When the difference between the original resistance and the designed resistance of the first target electrode piece is greater than the second difference and less than the third difference, determining that the resistance adjustment strategy for the first target electrode piece is to increase the coating surface thickness and / or increase the coating surface density;

[0029] When the difference between the original resistance and the designed resistance of the first target electrode is greater than the third difference, the resistance adjustment strategy of the first target electrode is determined to be replacing the original resistance with a first resistor, wherein the resistance value of the first resistor is greater than the resistance value of the original resistor.

[0030] This application also provides a battery cell design system, including:

[0031] An acquisition module is used to obtain the temperature value of each electrode in the battery cell to be improved;

[0032] A first determining module is used to determine the temperature difference between the temperature value of each electrode and the reference temperature value;

[0033] a calculation module, configured to perform a table lookup based on the temperature difference between the temperature value of each electrode piece and the reference temperature value to determine the design resistance of each electrode piece, wherein after the resistance of each electrode piece is adjusted to the design resistance, the temperature difference between the temperature value of each electrode piece and the reference temperature value is less than a first difference;

[0034] The second determination module is used to determine the difference between the designed resistance and the original resistance of each electrode;

[0035] A query module is used to query a first correspondence table based on the difference between the designed resistance and the original resistance of each electrode to determine the resistance adjustment strategy of each electrode, wherein the first correspondence table contains the correspondence between the resistance difference and the adjustment strategy, and the resistance adjustment strategy is used to adjust the resistance of each electrode from the original resistance to the designed resistance.

[0036] In one embodiment, the acquisition module includes:

[0037] A charging submodule, used to charge the battery cells to be improved;

[0038] The first acquisition submodule is used to acquire the temperature value of each electrode in the battery cell to be improved through temperature sensors arranged at various positions in the battery cell to be improved when the charging time of the battery cell to be improved reaches a preset time.

[0039] In one embodiment, the first determining module includes:

[0040] The second acquisition submodule is used to obtain the temperature value of the outermost electrode or a pre-stored temperature value;

[0041] The first determining submodule is used to determine the temperature value of the outermost electrode or the pre-stored temperature value as a reference temperature;

[0042] The calculation submodule is used to calculate the temperature difference between the temperature value of each electrode and the reference temperature value.

[0043] In one embodiment, the computing module includes:

[0044] a query submodule, configured to query a second correspondence table to determine an impedance difference between each electrode and a reference resistor based on a temperature difference between the temperature value of each electrode and the reference temperature value, wherein the reference temperature value corresponds to the reference resistor, and the second correspondence table is configured to record a correspondence between the temperature difference and the impedance difference;

[0045] The second determination submodule is used to determine the difference between the original resistance of each electrode piece and the impedance difference between each electrode piece and the reference resistance as the design resistance of each electrode piece.

[0046] In one embodiment, the query module includes:

[0047] When the difference between the designed resistance and the original resistance of each electrode piece is positive, determining the resistance adjustment strategy of each electrode piece includes at least one of the following adjustment strategies:

[0048] Increasing the coating surface thickness, increasing the coating surface density, increasing the compaction density of the resistor material, and replacing the original resistor with a first resistor, wherein the resistance of the first resistor is greater than the resistance of the original resistor;

[0049] When the difference between the designed resistance and the original resistance of each electrode is negative, determining the resistance adjustment strategy of each electrode includes reducing the coating surface thickness or replacing the original resistor with a second resistor, wherein the resistance of the second resistor is smaller than the resistance of the original resistor.

[0050] In one embodiment, when the difference between the designed resistance and the original resistance of each electrode piece is positive, the device further comprises:

[0051] a third determining module, configured to determine, when a difference between the original resistance and the designed resistance of the first target electrode piece is less than a second difference, that the resistance adjustment strategy for the first target electrode piece is to increase the compaction density of the resistance material;

[0052] a fourth determining module, configured to determine, when a difference between the original resistance and the designed resistance of the first target electrode piece is greater than the second difference and less than the third difference, that the resistance adjustment strategy for the first target electrode piece is to increase the coating surface thickness and / or increase the coating surface density;

[0053] The fifth determination module is used to determine that the resistance adjustment strategy of the first target electrode is to replace the original resistor with a first resistor when the difference between the original resistance and the designed resistance of the first target electrode is greater than the third difference, wherein the resistance value of the first resistor is greater than the resistance value of the original resistor.

[0054] The present application also provides a battery cell designed according to the battery cell design method described in any one of the above embodiments, the battery cell comprising:

[0055] A multi-layer pole piece, wherein the resistance of the impedance layer of the multi-layer pole piece decreases from the outside to the inside.

[0056] The present application also provides an electronic device, comprising:

[0057] at least one processor; and,

[0058] a memory communicatively connected to the at least one processor; wherein,

[0059] The memory stores instructions that can be executed by the at least one processor, and the instructions are executed by the at least one processor to implement the battery cell design method described in any one of the above embodiments.

[0060] The present application also provides a computer-readable storage medium. When the instructions in the storage medium are executed by a processor corresponding to an electronic device, the electronic device can implement the battery cell design method described in any one of the above embodiments.

[0061] Other features and advantages of the present application will be described in the following description, and in part will become apparent from the description, or will be understood by practicing the present application. The purposes and other advantages of the present application can be realized and obtained by the structures particularly pointed out in the written description, claims, and drawings.

[0062] The technical solution of the present application is further described in detail below through the accompanying drawings and examples. BRIEF DESCRIPTION OF THE DRAWINGS

[0063] The accompanying drawings are used to provide a further understanding of the present application and constitute a part of the specification. Together with the embodiments of the present application, they are used to explain the present application and do not constitute a limitation of the present application. In the accompanying drawings:

[0064] Figure 1 This is a flow chart of a battery cell design method in one embodiment of the present application;

[0065] Figure 2 This is a schematic diagram of a winding structure in one embodiment of the present application;

[0066] Figure 3 This is a schematic diagram of a laminate structure in one embodiment of the present application;

[0067] Figure 4 This is a schematic diagram of a pole winding group structure with different internal and external internal resistances in one embodiment of the present application;

[0068] Figure 5 This is a schematic structural diagram of a battery cell in one embodiment of the present application;

[0069] Figure 6 This is a block diagram of a battery cell design system in one embodiment of the present application;

[0070] Figure 7 This is a schematic diagram of the hardware structure of an electronic device in one embodiment of the present application. DETAILED DESCRIPTION

[0071] The preferred embodiments of the present application are described below in conjunction with the accompanying drawings. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present application and are not used to limit the present application.

[0072] Figure 1 This is a flow chart of a battery cell design method according to an embodiment of the present application. Figure 1 As shown, the method can be implemented as the following steps S101-S105:

[0073] In step S101, the temperature value of each electrode in the battery cell to be improved is obtained;

[0074] In step S102, the temperature difference between the temperature value of each electrode and the reference temperature value is determined;

[0075] In step S103, a table is looked up based on the temperature difference between the temperature value of each electrode and the reference temperature value to determine the design resistance of each electrode, wherein after the resistance of each electrode is adjusted to the design resistance, the temperature difference between the temperature value of each electrode and the reference temperature value is less than a first difference;

[0076] In step S104, the difference between the designed resistance and the original resistance of each electrode is determined;

[0077] In step S105, a first correspondence table is queried based on the difference between the designed resistance and the original resistance of each electrode to determine the resistance adjustment strategy of each electrode, wherein the first correspondence table contains the correspondence between the resistance difference and the adjustment strategy, and the resistance adjustment strategy is used to adjust the resistance of each electrode from the original resistance to the designed resistance.

[0078] The cell shapes are divided into square shell, cylinder, soft pack, blade, etc. The pole coils in the cell are formed by alternating winding or lamination of positive electrode sheet-diaphragm-negative electrode sheet, which is commonly referred to as winding and lamination structure. The square shell cell pole coil grouping methods are commonly winding and lamination. The cylinder is commonly wound, and the soft pack and blade are mostly laminated. The present invention can be adapted to the current pole sheet grouping forms with different windings or laminations, and is not limited to the cell shape. Taking the square shell wound cell as an example, the cell shell thickness varies between 20-60mm. The thickness of a single pole coil is commonly 20-30mm after winding. The thermal conductivity system in the thickness direction between the pole sheets is very low (usually 1W / mK, and the radial and axial thermal conductivity is 20-35W / mK). The heat dissipation at the center of each pole coil is poor, which is the area with the highest temperature in the cell. In particular, during the charge and discharge process of the cell, since the outer pole sheet contacts the shell and is cooled by the outside, the temperature difference between the inside and outside of the cell is more significant.

[0079] Therefore, it is necessary to improve the battery cell. In the present application, the temperature value of each pole piece in the battery cell to be improved can be obtained. Specifically, before obtaining the temperature value, the battery cell to be improved needs to be charged, and when the charging time of the battery cell to be improved reaches a preset time, the temperature value of each pole piece in the battery cell to be improved is obtained by temperature sensors set at various positions in the battery cell to be improved. Of course, it is understandable that when the battery is running, whether it is charging or discharging, there will be current passing through the battery. Therefore, it is also possible to discharge the battery cell to be improved, and when the discharge time of the battery cell to be improved reaches a preset time, the temperature value of each pole piece in the battery cell to be improved is obtained by temperature sensors set at various positions in the battery cell to be improved.

[0080] In this application, small temperature sensors can be installed on the pole pieces, diaphragms, and other locations in the battery cell to obtain the temperature value at each location. These temperature sensors can be connected to the battery management system (BMS) and feed the temperature data back to the BMS to help the BMS monitor the operating status of the battery cell, control the charging and discharging process, and predict battery life.

[0081] Determine the temperature difference between the temperature value of each electrode and the reference temperature value; specifically, obtain the temperature value of the outermost electrode or the pre-stored temperature value; determine the temperature value of the outermost electrode or the pre-stored temperature value as the reference temperature value; calculate the temperature difference between the temperature value of each electrode and the reference temperature value.

[0082] A table is looked up based on the temperature difference between the temperature value of each electrode and the reference temperature value to determine the design resistance of each electrode, wherein after the resistance of each electrode is adjusted to the design resistance, the temperature difference between the temperature value of each electrode and the reference temperature value is less than the first difference; it can be understood that after the resistance of each electrode is adjusted to the design resistance, the temperature difference between the temperature value of each electrode and the reference temperature value is 0, which is the most ideal situation, but considering that there may be certain errors in actual conditions, a maximum error threshold is introduced here, which is equal to the above-mentioned first difference, specifically 3°C, that is, the maximum allowable error is 3°C.

[0083] The difference between the original resistance of each electrode piece and the impedance difference between each electrode piece and the reference resistance is determined as the design resistance of each electrode piece.

[0084] In this application, after determining the design resistance of each electrode, the difference between the design resistance and the original resistance of each electrode is determined; then, based on the difference between the design resistance and the original resistance of each electrode, a first correspondence table is queried to determine the resistance adjustment strategy for each electrode, wherein the first correspondence table contains the correspondence between the resistance difference and the adjustment strategy, and the resistance adjustment strategy is used to adjust the resistance of each electrode from the original resistance to the design resistance. Specifically, the first correspondence table can be shown in Table 1 below:

[0085] Table 1

[0086] Resistance difference Adjustment strategy Less than 4% Increase the compaction density of the resistor material More than 4%, less than 8% Increase coating thickness and / or increase coating density More than 8% Replace the resistor material to increase the resistance value More than -8%, less than -4% Reduce coating surface thickness Less than -8% Replace the resistor material to reduce the resistance value

[0087] Specifically, when the difference between the designed resistance and the original resistance of each electrode is positive, the resistance adjustment strategy of each electrode is determined to include at least one of the following adjustment strategies: increasing the coating surface thickness, increasing the coating surface density, increasing the compaction density of the resistance material, and replacing the original resistor with a first resistor, wherein the resistance value of the first resistor is greater than the resistance value of the original resistor; when the difference between the designed resistance and the original resistance of each electrode is negative, the resistance adjustment strategy of each electrode is determined to include reducing the coating surface thickness or replacing the original resistor with a second resistor, wherein the resistance value of the second resistor is less than the resistance value of the original resistor.

[0088] Among them, when the difference between the designed resistance and the original resistance of each electrode is positive, if the difference between the original resistance and the designed resistance of the first target electrode is less than the second difference, the resistance adjustment strategy of the first target electrode is determined to be to increase the coating surface thickness or to increase the coating surface density; if the difference between the original resistance and the designed resistance of the first target electrode is greater than the second difference and less than the third difference, the resistance adjustment strategy of the first target electrode is determined to be to increase the compaction density of the resistance material; if the difference between the original resistance and the designed resistance of the first target electrode is greater than the third difference, the resistance adjustment strategy of the first target electrode is determined to be to replace the original resistor with the first resistor, wherein the resistance value of the first resistor is greater than the resistance value of the original resistor.

[0089] For example, in this application, a single pole roll is usually composed of more than 100 pole pieces, and the winding structure is as follows: Figure 2 As shown, the structure after lamination is as follows Figure 3 As shown, the internal resistance (impedance) of the electrodes is designed from large to small from the outside to the inside of the single-pole coil, so as to gradually reduce the heat generated by the electrodes, thereby compensating for the difference caused by the inconsistency of the heat dissipation capacity from the outside to the inside. Specifically, the second correspondence table can be queried based on the temperature difference between the temperature value of each electrode and the reference temperature value to determine the impedance difference between each electrode and the reference resistance, wherein the reference temperature value corresponds to the reference resistance, and the second correspondence table is used to record the correspondence between the temperature difference and the impedance difference.

[0090] The second corresponding relationship table is shown in Table 2 below:

[0091] Table 2

[0092]

[0093]

[0094] It can be understood that the electrode gradients of different heat generation designs are grouped, and from the outer edge to the inside of the core, the electrode impedance is from large to small, with different impedance gradients. Under the same operating time, such as the temperature difference between the electrode temperature and the reference temperature is 5°C, by querying the second correspondence table, it can be seen that the impedance difference between the electrode and the reference resistance is 0.05mΩ, where battery operation includes battery charging or battery discharging.

[0095] In addition, in addition to the different designs of pole piece impedance gradients within a single pole roll, pole rolls can also be grouped according to different pole roll positions, such as Figure 4 As shown, a pole winding group design with different internal resistance inside and outside is provided. The pole winding near the center adopts the pole piece with small internal resistance, and the pole piece near the outside of the shell adopts the pole piece with large internal resistance. Figure 2-3 The same approach is used, except that the high and low internal resistances are distributed on different pole coils.

[0096] Below, the temperature difference of the battery before and after the implementation of the technical solution of this application is statistically analyzed through experiments:

[0097] Before the technical solution of this application is implemented, after the battery has been running for a certain period of time, the temperature of each electrode is as shown in Table 3 below:

[0098] Table 3

[0099] Run time (min) 30 60 90 Innermost electrode temperature (℃) 32 40 50 Intermediate layer pole piece temperature (℃) 29 35 43 Outermost electrode temperature (℃) 27 30 35

[0100] Through experiments, it can be found that after implementing the technical solution of this application, after the battery has been running for a certain period of time, the temperature difference of each electrode can be controlled within the range of 0-3°C. The temperature conditions of each electrode are shown in Table 4 below:

[0101] Table 4

[0102] Run time (min) 30 60 90 Innermost electrode temperature (℃) 33 36 40 Intermediate layer pole piece temperature (℃) 31 35 39 Outermost electrode temperature (℃) 30 33 37

[0103] The beneficial effects of the present application are that: a table can be looked up based on the temperature difference between the temperature value of each electrode and the reference temperature value to determine the design resistance of each electrode, wherein, after the resistance of each electrode is adjusted to the design resistance, the temperature difference between the temperature value of each electrode and the reference temperature value is less than a first difference; the resistance adjustment strategy of each electrode is determined by the difference between the design resistance and the original resistance of each electrode, which is used to adjust the resistance of each electrode from the original resistance to the design resistance, so that the resistance of each electrode is adjusted to the design resistance through this scheme, and then the temperature difference between the temperature value of each electrode and the reference temperature value is less than the first difference, thereby reducing the temperature difference of electrodes at different positions in the battery cell and improving the safety of the battery cell.

[0104] In one embodiment, the above step S101 may be implemented as the following steps A1-A2:

[0105] In step A1, the battery cell to be improved is charged;

[0106] In step A2, when the charging time of the battery cell to be improved reaches a preset time, the temperature value of each electrode in the battery cell to be improved is obtained by temperature sensors arranged at various positions in the battery cell to be improved.

[0107] In one embodiment, the above step S102 may be implemented as the following steps B1-B4:

[0108] In step B1, the battery cell to be improved is charged;

[0109] In step B2, the temperature value of the outermost electrode or a pre-stored temperature value is obtained;

[0110] In step B3, the temperature value of the outermost electrode or the pre-stored temperature value is determined as the reference temperature value;

[0111] In step B4, the temperature difference between the temperature value of each electrode and the reference temperature value is calculated.

[0112] In one embodiment, the above step S103 may be implemented as the following steps C1-C2:

[0113] In step C1, a second correspondence table is queried based on the temperature difference between the temperature value of each electrode and the reference temperature value to determine the impedance difference between each electrode and the reference resistor, wherein the reference temperature value corresponds to the reference resistor, and the second correspondence table is used to record the correspondence between the temperature difference and the impedance difference;

[0114] In step C2, the difference obtained by subtracting the impedance difference between each electrode piece and a reference resistance from the original resistance of each electrode piece is determined as the design resistance of each electrode piece.

[0115] In one embodiment, the step S105 of querying the first correspondence table according to the difference between the designed resistance and the original resistance of each electrode piece to determine the resistance adjustment strategy of each electrode piece can be implemented as the following steps D1-D2:

[0116] In step D1, when the difference between the designed resistance and the original resistance of each electrode piece is positive, determining the resistance adjustment strategy of each electrode piece includes at least one of the following adjustment strategies:

[0117] Increasing the coating surface thickness, increasing the coating surface density, increasing the compaction density of the resistor material, and replacing the original resistor with a first resistor, wherein the resistance of the first resistor is greater than the resistance of the original resistor;

[0118] In step D2, when the difference between the designed resistance and the original resistance of each electrode is negative, determining the resistance adjustment strategy of each electrode includes reducing the coating surface thickness or replacing the original resistor with a second resistor, wherein the resistance of the second resistor is smaller than the resistance of the original resistor.

[0119] In this embodiment, impedances of different gradients can be achieved by changing the coating thickness (or coating surface density). The smaller the coating thickness, the smaller the diffusion path of the liquid and solid phases of lithium ions, and the lower the impedance. Specifically, the commonly used ternary battery cell gradually decreases from 90g / m2 to 85g / m2 from the inner ring low-impedance electrode to the outer ring high-impedance electrode area, and the inner and outer ring impedances can be reduced by ~4%, and the temperature difference can be reduced by ~1.5°C. In addition, it can also be achieved by adjusting the compaction density of the resistor material. The reduction in compaction density is beneficial to improving the porosity of the electrode material and improving the electrolyte infiltration, and is also beneficial to reducing the liquid phase diffusion impedance and solid phase diffusion impedance of lithium ions, thereby reducing the impedance. In order to achieve different impedances, the compaction density can also be fine-tuned from small to large from the outside to the inside. Of course, different impedance materials can also be used to achieve resistance adjustment. For example, the positive electrode material in the inner circle of the battery cell can use a low-impedance positive electrode material with more active sites, and the negative electrode material in the inner circle, such as graphite material, can use a higher kinetic graphite material. Compared with low-kinetic graphite, smaller primary particles can be used, as well as a mix of primary and secondary particles.

[0120] In one embodiment, when the difference between the designed resistance and the original resistance of each electrode piece is positive, the method may further be implemented as the following steps E1-E3:

[0121] In step E1, when the difference between the original resistance and the designed resistance of the first target electrode piece is less than the second difference, determining that the resistance adjustment strategy of the first target electrode piece is to increase the compaction density of the resistance material;

[0122] In step E2, when the difference between the original resistance and the designed resistance of the first target electrode piece is greater than the second difference and less than the third difference, determining that the resistance adjustment strategy of the first target electrode piece is to increase the coating surface thickness and / or increase the coating surface density;

[0123] In step E3, when the difference between the original resistance and the designed resistance of the first target electrode is greater than the third difference, the resistance adjustment strategy of the first target electrode is determined to be replacing the original resistance with a first resistor, wherein the resistance value of the first resistor is greater than the resistance value of the original resistor.

[0124] Figure 5 A block diagram of a battery cell design system for this application is shown below. Figure 5 As shown, including:

[0125] An acquisition module 501 is used to obtain the temperature value of each electrode in the battery cell to be improved;

[0126] A first determining module 502 is used to determine the temperature difference between the temperature value of each electrode and the reference temperature value;

[0127] a calculation module 503 configured to perform a table lookup based on the temperature difference between the temperature value of each electrode and the reference temperature value to determine a design resistance of each electrode, wherein after the resistance of each electrode is adjusted to the design resistance, the temperature difference between the temperature value of each electrode and the reference temperature value is less than a first difference;

[0128] The second determining module 504 is used to determine the difference between the designed resistance and the original resistance of each electrode;

[0129] The query module 505 is used to query the first correspondence table based on the difference between the design resistance and the original resistance of each electrode to determine the resistance adjustment strategy of each electrode, wherein the first correspondence table contains the correspondence between the resistance difference and the adjustment strategy, and the resistance adjustment strategy is used to adjust the resistance of each electrode from the original resistance to the design resistance.

[0130] In one embodiment, the acquisition module includes:

[0131] A charging submodule, used to charge the battery cells to be improved;

[0132] The first acquisition submodule is used to acquire the temperature value of each electrode in the battery cell to be improved through temperature sensors arranged at various positions in the battery cell to be improved when the charging time of the battery cell to be improved reaches a preset time.

[0133] In one embodiment, the first determining module includes:

[0134] The second acquisition submodule is used to obtain the temperature value of the outermost electrode or a pre-stored temperature value;

[0135] The first determining submodule is used to determine the temperature value of the outermost electrode or the pre-stored temperature value as a reference temperature;

[0136] The calculation submodule is used to calculate the temperature difference between the temperature value of each electrode and the reference temperature value.

[0137] In one embodiment, the computing module includes:

[0138] a query submodule, configured to query a second correspondence table to determine an impedance difference between each electrode and a reference resistor based on a temperature difference between the temperature value of each electrode and the reference temperature value, wherein the reference temperature value corresponds to the reference resistor, and the second correspondence table is configured to record a correspondence between the temperature difference and the impedance difference;

[0139] The second determination submodule is used to determine the difference between the original resistance of each electrode piece and the impedance difference between each electrode piece and the reference resistance as the design resistance of each electrode piece.

[0140] In one embodiment, the query module includes:

[0141] When the difference between the designed resistance and the original resistance of each electrode piece is positive, determining the resistance adjustment strategy of each electrode piece includes at least one of the following adjustment strategies:

[0142] Increasing the coating surface thickness, increasing the coating surface density, increasing the compaction density of the resistor material, and replacing the original resistor with a first resistor, wherein the resistance of the first resistor is greater than the resistance of the original resistor;

[0143] When the difference between the designed resistance and the original resistance of each electrode is negative, determining the resistance adjustment strategy of each electrode includes reducing the coating surface thickness or replacing the original resistor with a second resistor, wherein the resistance of the second resistor is smaller than the resistance of the original resistor.

[0144] In one embodiment, when the difference between the designed resistance and the original resistance of each electrode piece is positive, the device further comprises:

[0145] a third determining module, configured to determine, when a difference between the original resistance and the designed resistance of the first target electrode piece is less than a second difference, that the resistance adjustment strategy for the first target electrode piece is to increase the compaction density of the resistance material;

[0146] a fourth determining module, configured to determine, when a difference between the original resistance and the designed resistance of the first target electrode piece is greater than the second difference and less than the third difference, that the resistance adjustment strategy for the first target electrode piece is to increase the coating surface thickness and / or increase the coating surface density;

[0147] The fifth determination module is used to determine that the resistance adjustment strategy of the first target electrode is to replace the original resistor with a first resistor when the difference between the original resistance and the designed resistance of the first target electrode is greater than the third difference, wherein the resistance value of the first resistor is greater than the resistance value of the original resistor.

[0148] Figure 6 This is a schematic structural diagram of a battery cell designed according to the battery cell design method described in any one of the above embodiments of the present application, as shown in FIG. Figure 6 As shown, the battery cell includes:

[0149] A multi-layer pole piece, wherein the resistance of the impedance layer of the multi-layer pole piece decreases from the outside to the inside.

[0150] like Figure 6As shown, the outer pole piece and the inner pole piece belong to a pair of relative concepts. For example, among two adjacent pole pieces, the one closer to the outermost pole piece 62 is the outer pole piece, and the one closer to the innermost pole piece 61 is the inner pole piece corresponding to the outer pole piece.

[0151] Figure 7 This is a schematic diagram of the hardware structure of an electronic device in an embodiment of the present application. Figure 7 As shown, the electronic device includes:

[0152] at least one processor 720; and,

[0153] A memory 704 in communication with the at least one processor 720; wherein,

[0154] The memory 704 stores instructions that can be executed by the at least one processor 720 , and the instructions are executed by the at least one processor 720 to implement the battery cell design method described in any of the above embodiments.

[0155] Reference Figure 7 The electronic device 700 may include one or more of the following components: a processing component 702 , a memory 704 , a power component 706 , a multimedia component 708 , an audio component 710 , an input / output (I / O) interface 712 , a sensor component 714 , and a communication component 716 .

[0156] The processing component 702 generally controls the overall operation of the electronic device 700. The processing component 702 may include one or more processors 720 to execute instructions to perform all or part of the steps of the above-described method. In addition, the processing component 702 may include one or more modules to facilitate interaction between the processing component 702 and other components. For example, the processing component 702 may include a multimedia module to facilitate interaction between the multimedia component 708 and the processing component 702.

[0157] The memory 704 is configured to store various types of data to support the operation of the electronic device 700. Examples of such data include instructions for any application or method operating on the electronic device 700, such as text, pictures, videos, etc. The memory 704 can be implemented by any type of volatile or non-volatile storage device or a combination thereof, such as static random access memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic memory, flash memory, magnetic disk, or optical disk.

[0158] The power supply component 706 provides power to the various components of the electronic device 700. The power supply component 706 may include a power management system, one or more power supplies, and other components associated with generating, managing, and distributing power to the electronic device 700.

[0159] The multimedia component 708 includes a screen that provides an output interface between the electronic device 700 and the user. In some embodiments, the screen may include a liquid crystal display (LCD) and a touch panel (TP). If the screen includes a touch panel, the screen may be implemented as a touch screen to receive input signals from the user. The touch panel includes one or more touch sensors to sense touches, slides, and gestures on the touch panel. The touch sensor can not only sense the boundaries of a touch or slide action, but also detect the duration and pressure associated with the touch or slide operation. In some embodiments, the multimedia component 708 may also include a front camera and / or a rear camera. When the electronic device 700 is in an operating mode, such as a shooting mode or a video mode, the front camera and / or the rear camera can receive external multimedia data. Each front camera and rear camera can be a fixed optical lens system or have a focal length and optical zoom capability.

[0160] The audio component 710 is configured to output and / or input audio signals. For example, the audio component 710 includes a microphone (MIC), and when the electronic device 700 is in an operating mode, such as an alarm mode, a recording mode, a voice recognition mode, and a voice output mode, the microphone is configured to receive external audio signals. The received audio signal can be further stored in the memory 704 or transmitted via the communication component 716. In some embodiments, the audio component 710 also includes a speaker for outputting audio signals.

[0161] I / O interface 712 provides an interface between processing component 702 and peripheral interface modules, such as a keyboard, click wheel, buttons, etc. These buttons may include but are not limited to: a home button, volume buttons, a start button, and a lock button.

[0162] The sensor assembly 714 includes one or more sensors for providing various aspects of status assessment for the electronic device 700. For example, the sensor assembly 714 may include a sound sensor. In addition, the sensor assembly 714 can detect the open / closed state of the electronic device 700, the relative positioning of components, such as the display and keypad of the electronic device 700. The sensor assembly 714 can also detect the operating state of the electronic device 700 or a component of the electronic device 700, such as the operating state of the air distribution plate, the structural state, the operating state of the discharge scraper, etc., the orientation or acceleration / deceleration of the electronic device 700 and the temperature change of the electronic device 700. The sensor assembly 714 may include a proximity sensor configured to detect the presence of nearby objects without any physical contact. The sensor assembly 714 may also include a light sensor, such as a CMOS or CCD image sensor, for use in imaging applications. In some embodiments, the sensor assembly 714 may also include an acceleration sensor, a gyroscope sensor, a magnetic sensor, a pressure sensor, a material stacking thickness sensor or a temperature sensor.

[0163] The communication component 716 is configured to enable the electronic device 700 to provide the ability to communicate with other devices and cloud platforms in a wired or wireless manner. The electronic device 700 can access a wireless network based on a communication standard, such as WiFi, 2G or 3G, or a combination thereof. In an exemplary embodiment, the communication component 716 receives a broadcast signal or broadcast-related information from an external broadcast management system via a broadcast channel. In an exemplary embodiment, the communication component 716 also includes a near field communication (NFC) module to facilitate short-range communication. For example, the NFC module can be implemented based on radio frequency identification (RFID) technology, infrared data association (IrDA) technology, ultra-wideband (UWB) technology, Bluetooth (BT) technology and other technologies.

[0164] In an exemplary embodiment, the electronic device 700 can be implemented by one or more application-specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs), field programmable gate arrays (FPGAs), controllers, microcontrollers, microprocessors or other electronic components to execute the battery cell design method described in any of the above embodiments.

[0165] The present application also provides a computer-readable storage medium. When the instructions in the storage medium are executed by a processor corresponding to an electronic device, the electronic device can implement the battery cell design method described in any one of the above embodiments.

[0166] Those skilled in the art will appreciate that the embodiments of the present application can be provided as methods, systems, or computer program products. Therefore, the present application can adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application can adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage and optical storage, etc.) that contain computer-usable program code.

[0167] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the steps in the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0168] These computer program instructions may also be stored in a computer readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 a process or multiple processes and / or boxes Figure 1 The function specified in one or more boxes.

[0169] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing the instructions executed on the computer or other programmable device for implementing the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0170] Obviously, those skilled in the art may make various changes and modifications to this application without departing from the spirit and scope of this application. Thus, if these modifications and variations of this application fall within the scope of the claims of this application and their equivalents, this application is intended to include these modifications and variations.

Claims

1. A battery cell design method, characterized in that: include: Obtain the temperature value of each electrode in the battery cell to be improved; Determine the temperature difference between the temperature value of each electrode and the reference temperature value; A table is looked up based on the temperature difference between the temperature value of each electrode and the reference temperature value to determine the design resistance of each electrode, wherein after the resistance of each electrode is adjusted to the design resistance, the temperature difference between the temperature value of each electrode and the reference temperature value is less than a first difference; Determine the difference between the designed resistance and the original resistance of each electrode; The first correspondence table is queried based on the difference between the designed resistance and the original resistance of each electrode to determine the resistance adjustment strategy of each electrode, wherein the first correspondence table contains the correspondence between the resistance difference and the adjustment strategy, and the resistance adjustment strategy is used to adjust the resistance of each electrode from the original resistance to the designed resistance.

2. The method according to claim 1, wherein The step of obtaining the temperature value of each electrode in the battery cell to be improved includes: Charge the battery cells to be improved; When the charging time of the battery cell to be improved reaches a preset time, the temperature value of each electrode in the battery cell to be improved is obtained by temperature sensors arranged at various positions in the battery cell to be improved.

3. The method according to claim 1, wherein Determining the temperature difference between the temperature value of each electrode and the reference temperature value includes: Obtain the temperature value of the outermost electrode or the pre-stored temperature value; Determine the temperature value of the outermost electrode or the pre-stored temperature value as the reference temperature value; The temperature difference between the temperature value of each electrode and the reference temperature value is calculated.

4. The method according to claim 1, wherein The step of looking up a table based on the temperature difference between the temperature value of each electrode and the reference temperature value to determine the design resistance of each electrode includes: querying a second correspondence table according to the temperature difference between the temperature value of each electrode and the reference temperature value to determine the impedance difference between each electrode and the reference resistor, wherein the reference temperature value corresponds to the reference resistor, and the second correspondence table is used to record the correspondence between the temperature difference and the impedance difference; The difference between the original resistance of each electrode piece and the impedance difference between each electrode piece and the reference resistance is determined as the design resistance of each electrode piece.

5. The method according to claim 1, wherein The first correspondence table is searched according to the difference between the designed resistance and the original resistance of each electrode to determine the resistance adjustment strategy of each electrode, including: When the difference between the designed resistance and the original resistance of each electrode piece is positive, determining that the resistance adjustment strategy for each electrode piece includes at least one of the following adjustment strategies: increasing the coating surface thickness, increasing the coating surface density, increasing the compaction density of the resistor material, and replacing the original resistor with a first resistor, wherein the resistance of the first resistor is greater than the resistance of the original resistor; When the difference between the designed resistance and the original resistance of each electrode is negative, determining the resistance adjustment strategy of each electrode includes reducing the coating surface thickness and / or replacing the original resistor with a second resistor, wherein the resistance of the second resistor is smaller than the resistance of the original resistor.

6. The method according to claim 5, wherein When the difference between the designed resistance and the original resistance of each electrode piece is positive, the method further includes: When the difference between the original resistance and the designed resistance of the first target electrode piece is less than the second difference, determining that the resistance adjustment strategy for the first target electrode piece is to increase the compaction density of the resistance material; When the difference between the original resistance and the designed resistance of the first target electrode piece is greater than the second difference and less than the third difference, determining that the resistance adjustment strategy for the first target electrode piece is to increase the coating surface thickness and / or increase the coating surface density; When the difference between the original resistance and the designed resistance of the first target electrode is greater than the third difference, the resistance adjustment strategy of the first target electrode is determined to be replacing the original resistance with a first resistor, wherein the resistance value of the first resistor is greater than the resistance value of the original resistor.

7. A battery cell design system, characterized in that: include: An acquisition module is used to obtain the temperature value of each electrode in the battery cell to be improved; A first determining module is used to determine the temperature difference between the temperature value of each electrode and the reference temperature value; a calculation module, configured to perform a table lookup based on the temperature difference between the temperature value of each electrode piece and the reference temperature value to determine the design resistance of each electrode piece, wherein after the resistance of each electrode piece is adjusted to the design resistance, the temperature difference between the temperature value of each electrode piece and the reference temperature value is less than a first difference; The second determination module is used to determine the difference between the designed resistance and the original resistance of each electrode; A query module is used to query a first correspondence table based on the difference between the designed resistance and the original resistance of each electrode to determine the resistance adjustment strategy of each electrode, wherein the first correspondence table contains the correspondence between the resistance difference and the adjustment strategy, and the resistance adjustment strategy is used to adjust the resistance of each electrode from the original resistance to the designed resistance.

8. A battery cell designed according to the battery cell design method according to any one of claims 1 to 6, characterized in that: The battery cell comprises: A multi-layer pole piece, wherein the resistance of the impedance layer of the multi-layer pole piece decreases from the outside to the inside.

9. An electronic device, characterized in that: include: at least one processor; as well as, a memory communicatively connected to the at least one processor; wherein, The memory stores instructions that can be executed by the at least one processor, and the instructions are executed by the at least one processor to implement the battery cell design method according to any one of claims 1 to 6.

10. A computer-readable storage medium, characterized in that When the instructions in the storage medium are executed by a processor corresponding to the electronic device, the electronic device can implement the battery cell design method according to any one of claims 1 to 6.

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