Method and device for calculating maximum output current of parallel battery pack

Abstract

The invention relates to the technical field of battery packs, and provides a maximum output current calculation method and device of a parallel battery pack, and the method comprises the steps: obtaining a minimum temperature; for each single battery, obtaining the residual charge quantity of the single battery and a first current value of the single battery, and calculating a current target current value of the single battery based on the lowest temperature, the residual charge quantity and the first current value; for each single battery, calculating the target internal resistance of the single battery based on the target current value and the residual charge quantity corresponding to the single battery; for each single battery, calculating a theoretical current value corresponding to each single battery based on the target current value corresponding to each single battery and the target internal resistance corresponding to each single battery; calculating an output current reduction factor based on the target current value and the theoretical current value corresponding to each single battery; and determining the maximum output current of the parallel battery pack based on the output current reduction factor and the target current value corresponding to each single battery. According to the method, the accuracy of the maximum output current calculation result is improved.

Description

Technical Field

[0001] The present application relates to the technical field of battery packs, and in particular to a method and device for calculating the maximum output current of a parallel battery pack. Background Art

[0002] As battery packs become increasingly widely used, especially in new energy vehicles and energy storage systems, performance requirements are constantly increasing. To ensure the normal operation of electrical equipment, it is crucial to correctly calculate the maximum output current of parallel battery packs. Current methods for calculating the maximum output current of parallel battery packs sum the current values ​​of multiple individual cells and then reduce the resulting total current by a certain percentage to prevent the output current of each cell from exceeding its safe current range. This method does not consider the effects of the temperature and internal resistance of each cell on the output current, which can easily result in the calculated maximum output current being outside the safe range. Summary of the Invention

[0003] This application provides a method and device for calculating the maximum output current of a parallel battery pack to solve the problems raised by the above background technology.

[0004] In a first aspect, the present application provides a method for calculating the maximum output current of a parallel battery pack, comprising: Obtaining the lowest temperature among the temperatures corresponding to the single cells in the parallel battery pack; For each of the single cells, obtaining the remaining charge of the single cell and a first current value of the single cell, and calculating a target current value for the single cell based on the minimum temperature, the remaining charge, and the first current value; wherein the first current value is a result of a previous calculation of the target current value for the single cell; For each of the single cells, calculating a target internal resistance of the single cell based on a target current value and a remaining charge of the single cell; For each of the single cells, calculating a theoretical current value of the single cell based on a target current value of the single cell and a target internal resistance of the single cell; Calculating an output current reduction factor based on a target current value and a theoretical current value of each of the single cells; The maximum output current of the parallel battery group is determined based on the output current reduction factor and the target current value of each of the single batteries.

[0005] In a possible implementation, the calculating the current target current value of the single battery based on the minimum temperature, the remaining charge, and the first current value includes: obtain a preset current value matching table, and determine a second current value corresponding to the single battery based on the lowest temperature, the residual charge amount, and the current value matching table; calibrate the second current value based on a preset current value calibration method to obtain a current calibration value corresponding to the second current value; calculate a target current value of the single battery at this time based on a first weight coefficient corresponding to the first current value and a second weight coefficient corresponding to the current calibration value.

[0006] In a possible implementation, the determination of the second current value corresponding to the single battery based on the lowest temperature, the residual charge amount, and the current value matching table comprises: determining whether the lowest temperature and the residual charge amount exist in the current value matching table; if the lowest temperature and the residual charge amount both exist in the current value matching table, determining that the current value corresponding to the lowest temperature and the residual charge amount in the current value matching table is the second current value; if the lowest temperature and / or the residual charge amount does not exist in the current value matching table, determining the second current value based on a preset linear algorithm and the current value matching table.

[0007] In a possible implementation, the calibration of the second current value based on the preset current value calibration method to obtain the current calibration value corresponding to the second current value comprises: determining whether a voltage value of the single battery when the target current value of the single battery is calculated last time is less than a first preset voltage value; if the voltage value of the single battery when the target current value of the single battery is calculated last time is less than the first preset voltage value, determining whether a current voltage value of the single battery is less than a preset voltage recovery value; if the current voltage value of the single battery is less than the preset voltage recovery value, reducing the second current value based on a first current reduction method to obtain an intermediate current calibration value, and determining whether a charge-discharge cycle number of the single battery is greater than a preset number, if the charge-discharge cycle number of the single battery is greater than the preset number, reducing the intermediate current calibration value based on a second current reduction method to obtain the current calibration value, if the charge-discharge cycle number of the single battery is not greater than the preset number, determining that the intermediate current calibration value is the current calibration value; If the current voltage value of the single battery is not less than a first preset voltage value, determining whether the number of charge and discharge cycles of the single battery is greater than a preset number; if the number of charge and discharge cycles of the single battery is greater than the preset number, reducing the second current value based on a preset second current reduction method to obtain the current calibration value; if the number of charge and discharge cycles of the single battery is not greater than the preset number, determining the second current value to be the current calibration value; If the voltage value of the single cell was not less than a first preset voltage value when the target current value of the single cell was calculated last time, determining whether the current voltage value of the single cell is less than a second preset voltage value; wherein the second preset voltage value is less than the first preset voltage value; If the current voltage value of the single battery is less than the second preset voltage value, the second current value is reduced based on the third current reduction method to obtain an intermediate current calibration value, and it is determined whether the number of charge and discharge cycles of the single battery is greater than the preset number; if the number of charge and discharge cycles of the single battery is greater than the preset number, the intermediate current calibration value is reduced based on the second current reduction method to obtain the current calibration value; if the number of charge and discharge cycles of the single battery is not greater than the preset number, the intermediate current calibration value is determined to be the current calibration value; If the current voltage value of the single battery is not less than a second preset voltage value, determine whether the number of charge and discharge cycles of the single battery is greater than a preset number; if the number of charge and discharge cycles of the single battery is greater than the preset number, reduce the second current value based on a preset second current reduction method to obtain the current calibration value; if the number of charge and discharge cycles of the single battery is not greater than the preset number, determine the second current value as the current calibration value.

[0008] In a possible implementation, calculating the target internal resistance of the single cell based on the target current value and the remaining charge corresponding to the single cell includes: Obtaining a preset voltage value matching table, and determining a theoretical voltage value corresponding to the single battery based on the target current value, the remaining charge, and the voltage value matching table; The target internal resistance is determined based on the theoretical voltage value, the target current value, and the system internal resistance corresponding to the single battery.

[0009] In a possible implementation, the calculating the theoretical current value corresponding to each single cell based on the target current value corresponding to each single cell and the target internal resistance corresponding to each single cell includes: For each of the single cells, Determine the theoretical current intermediate value corresponding to the single battery; wherein, is the theoretical current median value corresponding to the single cell, Representative parallel battery packs include Single battery, Indicates the The target internal resistance of each single cell, is the target internal resistance of the single cell, For the Target current value of each single cell; Based on the target internal resistance of each single cell, a theoretical current value is matched for each single cell in the intermediate value of each theoretical current; the theoretical current value corresponding to each single cell is negatively correlated with the target internal resistance corresponding to each single cell.

[0010] In a possible implementation, the calculating the output current reduction factor based on the target current value and the theoretical current value of each single battery includes: For each of the single cells, comparing the target current value corresponding to the single cell with the theoretical current value, and if the theoretical current value is greater than the target current value, determining that the single cell is a target single cell; Adding the target current values ​​of the target single cells to obtain a sum of first current values, and adding the theoretical current values ​​of the target single cells to obtain a sum of second current values; A ratio of the sum of the first current values ​​to the sum of the second current values ​​is determined as the output current reduction factor.

[0011] In a second aspect, the present application provides a device for calculating the maximum output current of a parallel battery pack, comprising: An acquisition module, configured to acquire the lowest temperature among the temperatures corresponding to the individual cells in the parallel battery pack; a first calculation module configured to obtain, for each of the single cells, a remaining charge of the single cell and a first current value of the single cell, and calculate a current target current value of the single cell based on the minimum temperature, the remaining charge, and the first current value; wherein the first current value is a result of a previous calculation of the target current value of the single cell; a second calculation module, configured to calculate, for each of the single cells, a target internal resistance of the single cell based on a target current value and a remaining charge of the single cell; a third calculation module, configured to calculate, for each of the single cells, a theoretical current value of the single cell based on a target current value of the single cell and a target internal resistance of the single cell; a fourth calculation module, configured to calculate an output current reduction factor based on a target current value and a theoretical current value of each of the single cells; A determination module is configured to determine a maximum output current of the parallel battery group based on the output current reduction factor and a target current value of each of the single batteries.

[0012] The present application provides a method and device for calculating the maximum output current of a parallel battery pack, the method comprising: obtaining the lowest temperature among the temperatures corresponding to each single cell in the parallel battery pack; for each single cell, obtaining the remaining charge of the single cell and the first current value of the single cell, and calculating the current target current value of the single cell based on the lowest temperature, the remaining charge and the first current value; wherein the first current value is the calculation result obtained by calculating the target current value of the single cell last time; for each single cell, calculating the target internal resistance of the single cell based on the target current value and the remaining charge of the single cell; for each single cell, calculating the theoretical current value of the single cell based on the target current value and the target internal resistance of the single cell; calculating the output current reduction factor based on the target current value and the theoretical current value of each single cell; and determining the maximum output current of the parallel battery pack based on the output current reduction factor and the target current value of each single cell. This method, on the one hand, accurately calculates the target current value for each cell by acquiring and analyzing factors such as the temperature, remaining charge, and first current value of each cell. Based on this information, it infers the target internal resistance and theoretical current value of each cell, thereby ensuring that the output current of each cell is within its safe range. This refined calculation method significantly improves the accuracy of the maximum output current of a parallel battery pack, avoiding errors caused by traditional methods that ignore the effects of temperature and internal resistance. Furthermore, by considering the difference between the target and theoretical current values ​​of a cell and combining it with the calculation of the output current reduction factor, this embodiment can more effectively balance the load between the cells, preventing damage to certain cells due to overload and ensuring that the battery pack maintains good safety even under high load conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0014] Figure 1 A flow chart of a method for calculating the maximum output current of a parallel battery pack provided in an embodiment of the present application; Figure 2 A schematic block diagram of the structure of a device for calculating the maximum output current of a parallel battery pack provided in an embodiment of the present application; Figure 3 A schematic block diagram of the structure of a terminal device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0015] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0016] The flowcharts shown in the accompanying drawings are for illustrative purposes only and do not necessarily include all contents and operations / steps, nor must they be executed in the order described. For example, some operations / steps may be decomposed, combined, or partially merged, so the actual execution order may change based on actual circumstances.

[0017] It should also be understood that the terms used in this specification are for the purpose of describing specific embodiments only and are not intended to limit the present application. As used in this specification and the appended claims, the singular forms "a," "an," and "the" are intended to include the plural forms unless the context clearly indicates otherwise.

[0018] It should be further understood that the term "and / or" used in this specification and the appended claims refers to any and all possible combinations of one or more of the associated listed items, and includes these combinations.

[0019] The following describes some embodiments of the present application in detail with reference to the accompanying drawings. In the absence of conflict, the following embodiments and features in the embodiments may be combined with each other.

[0020] See also Figure 1 , Figure 1 A flow chart of a method for calculating the maximum output current of a parallel battery pack provided in an embodiment of the present application is shown in FIG. Figure 1 As shown, the method for calculating the maximum output current of the parallel battery pack provided in the embodiment of the present application includes steps S1 to S6.

[0021] Step S1: Obtain the lowest temperature among the temperatures corresponding to the single cells in the parallel battery pack.

[0022] It should be noted that the embodiment of the present application is applied to the host, and the battery pack allocates the master and slave devices through communication handshake. The host is responsible for obtaining the slave information on the bus and executing the steps involved in this embodiment.

[0023] Specifically, each of the single batteries of the parallel battery pack is provided with a temperature sensor, the temperature of each single battery is obtained through the temperature sensor arranged on the single battery, and the lowest temperature is determined from the temperatures corresponding to the single batteries.

[0024] In step S2, for each single battery, the residual charge amount of the single battery and the first current value of the single battery are obtained, and the target current value of the single battery this time is calculated based on the lowest temperature, the residual charge amount and the first current value; wherein the first current value is the calculation result obtained by calculating the target current value of the single battery last time.

[0025] Specifically, for each single battery, the residual charge amount of the single battery is obtained based on the residual charge amount detection device arranged on the single battery, and the first current value corresponding to the single battery is obtained based on the database corresponding to the single battery.

[0026] The target current value of the single battery this time is calculated based on the lowest temperature, the residual charge amount and the first current value, including the following steps: A preset current value matching table is obtained, and the second current value corresponding to the single battery is determined based on the lowest temperature, the residual charge amount and the current value matching table; wherein the current value matching table is obtained by experiment, and the current value matching table is shown in Table 1; The second current value is calibrated based on a preset current value calibration method to obtain a current calibration value corresponding to the second current value; The target current value of the single battery this time is calculated based on the first weight coefficient corresponding to the first current value and the second weight coefficient corresponding to the current calibration value; specifically, the first current value is multiplied by the first weight coefficient to obtain a first product, the current calibration value is multiplied by the second weight coefficient to obtain a second product, and the first product and the second product are added to obtain the target current value.

[0027] The target current value of the single battery this time is calculated based on the first weight coefficient corresponding to the first current value and the second weight coefficient corresponding to the current calibration value; specifically, the first current value is multiplied by the first weight coefficient to obtain a first product, the current calibration value is multiplied by the second weight coefficient to obtain a second product, and the first product and the second product are added to obtain the target current value. It is judged whether the lowest temperature and the residual charge amount exist in the current value matching table; If the lowest temperature and the residual charge amount exist in the current value matching table, it is determined that the current value corresponding to the lowest temperature and the residual charge amount in the current value matching table is the second current value; for example, as shown in Table 1, if the residual charge amount is 90% and the lowest temperature is 10℃, the second current value is 55.38A; If the minimum temperature and / or the residual charge are not in the current value matching table, the second current value is determined based on a preset linear algorithm and the current value matching table; for example, if the minimum temperature is 10°C and the charge is 65%, the second current value is For example, if the minimum temperature is 10°C and the charge is 68%, then the second current value is For example, if the lowest temperature is 17.5°C and the charge is 60%, then the second current value is For example, if the lowest temperature is 13°C and the charge is 60%, then the second current value is .

[0028] The step of calibrating the second current value based on a preset current value calibration method to obtain a current calibration value corresponding to the second current value includes the following steps: determining whether the voltage value of the single cell is less than a first preset voltage value when the target current value of the single cell is calculated last time; If the voltage value of the single cell is less than the first preset voltage value when the target current value of the single cell is calculated last time, determining whether the current voltage value of the single cell is less than the preset voltage recovery value; If the current voltage value of the single battery is less than the preset voltage recovery value, the second current value is reduced based on a first current reduction method to obtain an intermediate current calibration value, and it is determined whether the number of charge and discharge cycles of the single battery is greater than a preset number. If the number of charge and discharge cycles of the single battery is greater than the preset number, the intermediate current calibration value is reduced based on a second current reduction method to obtain the current calibration value. If the number of charge and discharge cycles of the single battery is not greater than the preset number, the intermediate current calibration value is determined to be the current calibration value. The first current reduction method is to determine a first reduction coefficient based on the voltage difference between the current voltage value of the single battery and the first preset voltage value, and then multiply the second current value by the first reduction coefficient to obtain the intermediate current calibration value. The greater the voltage difference between the current voltage value of the single battery and the first preset voltage value, the smaller the first reduction coefficient. The second current reduction method is to determine a second reduction coefficient based on the difference between the preset number and the number of charge and discharge cycles, and then multiply the intermediate current calibration value by the second reduction coefficient to obtain the current calibration value. The greater the difference between the preset number and the number of charge and discharge cycles, the smaller the second reduction coefficient. If the current voltage value of the single battery is not less than a first preset voltage value, determining whether the number of charge and discharge cycles of the single battery is greater than a preset number; if the number of charge and discharge cycles of the single battery is greater than the preset number, reducing the second current value based on a preset second current reduction method to obtain the current calibration value; if the number of charge and discharge cycles of the single battery is not greater than the preset number, determining the second current value to be the current calibration value; If the voltage value of the single cell was not less than a first preset voltage value when the target current value of the single cell was calculated last time, determining whether the current voltage value of the single cell is less than a second preset voltage value; wherein the second preset voltage value is less than the first preset voltage value; If the current voltage value of the single battery is less than the second preset voltage value, the second current value is reduced based on a third current reduction method to obtain an intermediate current calibration value, and it is determined whether the number of charge and discharge cycles of the single battery is greater than the preset number. If the number of charge and discharge cycles of the single battery is greater than the preset number, the intermediate current calibration value is reduced based on the second current reduction method to obtain the current calibration value. If the number of charge and discharge cycles of the single battery is not greater than the preset number, the intermediate current calibration value is determined to be the current calibration value. The third current reduction method is to determine a third reduction coefficient based on the voltage difference between the current voltage value of the single battery and the second preset voltage value, and then multiply the second current value by the third reduction coefficient to obtain the intermediate current calibration value. The greater the voltage difference between the current voltage value of the single battery and the second preset voltage value, the smaller the third reduction coefficient. If the current voltage value of the single battery is not less than a second preset voltage value, determine whether the number of charge and discharge cycles of the single battery is greater than a preset number; if the number of charge and discharge cycles of the single battery is greater than the preset number, reduce the second current value based on a preset second current reduction method to obtain the current calibration value; if the number of charge and discharge cycles of the single battery is not greater than the preset number, determine the second current value as the current calibration value.

[0029] It can be understood that step S2 helps to improve the accuracy of the target current value through a multi-factor calculation method, thereby helping to improve the accuracy of the maximum output current.

[0030] Step S3: For each of the single cells, calculate the target internal resistance of the single cell based on the target current value and the remaining charge of the single cell.

[0031] Specifically, step S3 includes the following steps: Obtaining a preset voltage value matching table, and determining a theoretical voltage value corresponding to the single battery based on the target current value, the remaining charge, and the voltage value matching table; specifically, the voltage value matching table is obtained through experiments, and the method of determining the theoretical voltage value corresponding to the single battery based on the target current value, the remaining charge, and the voltage value matching table refers to the aforementioned method of determining the second current value corresponding to the single battery based on the minimum temperature, the remaining charge, and the current value matching table, which is not repeated here; The target internal resistance is determined based on the theoretical voltage value, the target current value and the system internal resistance corresponding to the single battery; specifically, the target internal resistance is obtained by adding the ratio of the theoretical voltage value to the target current value to the system internal resistance.

[0032] Step S4 : For each of the single cells, calculate the theoretical current value of the single cell based on the target current value of the single cell and the target internal resistance of the single cell.

[0033] Specifically, for each of the single cells, Determine the theoretical current intermediate value corresponding to the single battery; wherein, is the theoretical current median value corresponding to the single cell, Representative parallel battery packs include Single battery, Indicates the The target internal resistance of each single cell, is the target internal resistance of the single cell, For the Target current value of each single cell; Based on the target internal resistance of each single cell, a theoretical current value is matched for each single cell in the intermediate value of each theoretical current; the theoretical current value corresponding to each single cell is negatively correlated with the target internal resistance corresponding to each single cell.

[0034] Step S5: Calculating an output current reduction factor based on the target current value and the theoretical current value of each single battery.

[0035] Specifically, step S5 comprises the following steps; For each of the single cells, comparing the target current value corresponding to the single cell with the theoretical current value, and if the theoretical current value is greater than the target current value, determining that the single cell is a target single cell; Adding the target current values ​​of the target single cells to obtain a sum of first current values, and adding the theoretical current values ​​of the target single cells to obtain a sum of second current values; A ratio of the sum of the first current values ​​to the sum of the second current values ​​is determined as the output current reduction factor.

[0036] Step S6: Determine the maximum output current of the parallel battery pack based on the output current reduction factor and the target current value of each single cell; specifically, add the target current values ​​corresponding to each single cell to obtain the sum of the target current values, and multiply the sum of the target current values ​​by the output current reduction factor to obtain the maximum output current.

[0037] The method provided in this embodiment, on the one hand, accurately calculates the target current value of each cell by obtaining and analyzing factors such as the temperature, remaining charge, and first current value of each cell. Based on this information, it infers the target internal resistance and theoretical current value of each cell, thereby ensuring that the output current of each cell is within its safe range. This refined calculation method significantly improves the accuracy of the maximum output current of a parallel battery pack, avoiding errors caused by traditional methods that ignore the effects of temperature and internal resistance. Furthermore, by considering the difference between the target and theoretical current values ​​of a cell and combining it with the calculation of the output current reduction factor, this embodiment can more effectively balance the load between the cells, preventing damage to certain cells due to overload and ensuring that the battery pack maintains good safety even under high load conditions.

[0038] See also Figure 2 , Figure 2 A schematic block diagram of the structure of the maximum output current calculation device 100 for a parallel battery pack provided in an embodiment of the present application is shown as follows: Figure 2 As shown, the maximum output current calculation device 100 of the parallel battery pack provided in the embodiment of the present application includes: The acquisition module 110 is configured to acquire the lowest temperature among the temperatures corresponding to the single cells in the parallel battery pack.

[0039] The first calculation module 120 is used to obtain the remaining charge and the first current value of each single cell battery for each single cell battery, and calculate the current target current value of the single cell battery based on the minimum temperature, the remaining charge and the first current value; wherein the first current value is the calculation result obtained by calculating the target current value of the single cell battery last time.

[0040] The second calculation module 130 is configured to calculate, for each of the single cells, a target internal resistance of the single cell based on a target current value and a remaining charge of the single cell.

[0041] The third calculation module 140 is configured to calculate, for each of the single cells, a theoretical current value of the single cell based on a target current value of the single cell and a target internal resistance of the single cell.

[0042] The fourth calculation module 150 is configured to calculate an output current reduction factor based on the target current value and the theoretical current value of each of the single cells.

[0043] The determination module 160 is configured to determine the maximum output current of the parallel battery group based on the output current reduction factor and the target current value of each of the single batteries.

[0044] It should be noted that, those skilled in the art will clearly understand that, for the sake of convenience and brevity of description, the specific working processes of the above-described devices and modules can refer to the processes in the aforementioned embodiment of the method for calculating the maximum output current of the parallel battery pack, and will not be repeated here.

[0045] The maximum output current calculation device 100 of the parallel battery pack provided in the above embodiment can be implemented in the form of a computer program. The computer program can be used in Figure 3 The system runs on the terminal device 200 shown.

[0046] See also Figure 3 , Figure 3 This is a schematic block diagram of the structure of a terminal device 200 provided in an embodiment of the present application. The terminal device 200 includes a processor 201 and a memory 202. The processor 201 and the memory 202 are connected via a device bus 203, wherein the memory 202 may include a non-volatile storage medium and an internal memory.

[0047] The non-volatile storage medium may store a computer program including program instructions, which, when executed by the processor 201 , may cause the processor 201 to execute any of the above-mentioned methods for calculating the maximum output current of parallel battery packs.

[0048] The processor 201 is used to provide computing and control capabilities to support the operation of the entire terminal device 200.

[0049] The internal memory provides an environment for the operation of the computer program in the non-volatile storage medium. When the computer program is executed by the processor 201, the processor 201 can execute any of the above-mentioned methods for calculating the maximum output current of the parallel battery pack.

[0050] Those skilled in the art will understand that Figure 3The structure shown in the figure is only a block diagram of a part of the structure related to the solution of the present application, and does not constitute a limitation on the terminal device 200 involved in the solution of the present application. The specific terminal device 200 may include more or fewer components than shown in the figure, or combine certain components, or have a different component arrangement.

[0051] It should be understood that the processor 201 may be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor may be a microprocessor or any conventional processor.

[0052] In some embodiments, the processor 201 is configured to execute a computer program stored in the memory to implement the following steps: Obtaining the lowest temperature among the temperatures corresponding to the single cells in the parallel battery pack; For each of the single cells, obtaining the remaining charge of the single cell and a first current value of the single cell, and calculating a target current value for the single cell based on the minimum temperature, the remaining charge, and the first current value; wherein the first current value is a result of a previous calculation of the target current value for the single cell; For each of the single cells, calculating a target internal resistance of the single cell based on a target current value and a remaining charge of the single cell; For each of the single cells, calculating a theoretical current value of the single cell based on a target current value of the single cell and a target internal resistance of the single cell; Calculating an output current reduction factor based on a target current value and a theoretical current value of each of the single cells; The maximum output current of the parallel battery group is determined based on the output current reduction factor and the target current value of each of the single batteries.

[0053] It should be noted that, those skilled in the art will clearly understand that for the sake of convenience and brevity of description, the specific working process of the terminal device 200 described above can refer to the process of the maximum output current calculation method of the aforementioned parallel battery pack, which will not be repeated here.

[0054] The embodiment of the present application further provides a computer readable storage medium, which stores a computer program. The computer program, when executed by one or more processors, causes the one or more processors to implement the maximum output current calculation method of the parallel battery pack provided by the embodiment of the present application.

[0055] The computer readable storage medium can be an internal storage unit of the terminal device 200, for example, a hard disk or a memory of the terminal device 200. The computer readable storage medium can also be an external storage device of the terminal device 200, for example, a plug-in hard disk, a smart media card (SMC), a secure digital (SD) card, a flash card, etc.

[0056] The above merely provides the specific implementation of the present application, but the protection scope of the present application is not limited to this. Any person skilled in the art can easily think of various equivalent modifications or replacements within the technical range disclosed by the present application, and these modifications or replacements should be covered in the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A method for calculating the maximum output current of a parallel battery pack, characterized in that: include: Obtaining the lowest temperature among the temperatures corresponding to the single cells in the parallel battery pack; For each of the single cells, obtaining the remaining charge of the single cell and a first current value of the single cell, and calculating a target current value for the single cell based on the minimum temperature, the remaining charge, and the first current value; wherein the first current value is a result of a previous calculation of the target current value for the single cell; For each of the single cells, calculating a target internal resistance of the single cell based on a target current value and a remaining charge of the single cell; For each of the single cells, calculating a theoretical current value of the single cell based on a target current value of the single cell and a target internal resistance of the single cell; Calculating an output current reduction factor based on a target current value and a theoretical current value of each of the single cells; The maximum output current of the parallel battery group is determined based on the output current reduction factor and the target current value of each of the single batteries.

2. The method for calculating the maximum output current of a parallel battery pack according to claim 1, wherein: The calculating the current target current value of the single battery based on the minimum temperature, the remaining charge, and the first current value includes: Obtaining a preset current value matching table, and determining a second current value corresponding to the single battery based on the minimum temperature, the remaining charge, and the current value matching table; Calibrate the second current value based on a preset current value calibration method to obtain a current calibration value corresponding to the second current value; The current target current value of the single battery is calculated based on a first weight coefficient corresponding to the first current value and a second weight coefficient corresponding to the current calibration value.

3. The method for calculating the maximum output current of a parallel battery pack according to claim 2, wherein: The determining the second current value corresponding to the single battery based on the minimum temperature, the remaining charge, and the current value matching table includes: determining whether the minimum temperature and the residual charge are present in the current value matching table; If both the minimum temperature and the residual charge are present in the current value matching table, determining that the current value corresponding to the minimum temperature and the residual charge in the current value matching table is the second current value; If the lowest temperature and / or the residual charge amount does not exist in the current value matching table, the second current value is determined based on a preset linear algorithm and the current value matching table.

4. The method for calculating the maximum output current of a parallel battery pack according to claim 2, wherein: The step of calibrating the second current value based on a preset current value calibration method to obtain a current calibration value corresponding to the second current value includes: determining whether the voltage value of the single cell is less than a first preset voltage value when the target current value of the single cell is calculated last time; If the voltage value of the single cell is less than the first preset voltage value when the target current value of the single cell is calculated last time, determining whether the current voltage value of the single cell is less than the preset voltage recovery value; If the current voltage value of the single battery is less than the preset voltage recovery value, the second current value is reduced based on the first current reduction method to obtain an intermediate current calibration value, and it is determined whether the number of charge and discharge cycles of the single battery is greater than the preset number; if the number of charge and discharge cycles of the single battery is greater than the preset number, the intermediate current calibration value is reduced based on the second current reduction method to obtain the current calibration value; if the number of charge and discharge cycles of the single battery is not greater than the preset number, the intermediate current calibration value is determined to be the current calibration value; If the current voltage value of the single battery is not less than a first preset voltage value, determining whether the number of charge and discharge cycles of the single battery is greater than a preset number; if the number of charge and discharge cycles of the single battery is greater than the preset number, reducing the second current value based on a preset second current reduction method to obtain the current calibration value; if the number of charge and discharge cycles of the single battery is not greater than the preset number, determining the second current value to be the current calibration value; If the voltage value of the single cell was not less than a first preset voltage value when the target current value of the single cell was calculated last time, determining whether the current voltage value of the single cell is less than a second preset voltage value; wherein the second preset voltage value is less than the first preset voltage value; If the current voltage value of the single battery is less than the second preset voltage value, the second current value is reduced based on the third current reduction method to obtain an intermediate current calibration value, and it is determined whether the number of charge and discharge cycles of the single battery is greater than the preset number; if the number of charge and discharge cycles of the single battery is greater than the preset number, the intermediate current calibration value is reduced based on the second current reduction method to obtain the current calibration value; if the number of charge and discharge cycles of the single battery is not greater than the preset number, the intermediate current calibration value is determined to be the current calibration value; If the current voltage value of the single battery is not less than a second preset voltage value, determine whether the number of charge and discharge cycles of the single battery is greater than a preset number; if the number of charge and discharge cycles of the single battery is greater than the preset number, reduce the second current value based on a preset second current reduction method to obtain the current calibration value; if the number of charge and discharge cycles of the single battery is not greater than the preset number, determine the second current value as the current calibration value.

5. The method for calculating the maximum output current of a parallel battery pack according to claim 1, wherein: The calculating the target internal resistance of the single cell based on the target current value and the remaining charge corresponding to the single cell includes: Obtaining a preset voltage value matching table, and determining a theoretical voltage value corresponding to the single battery based on the target current value, the remaining charge, and the voltage value matching table; The target internal resistance is determined based on the theoretical voltage value, the target current value, and the system internal resistance corresponding to the single battery.

6. The method for calculating the maximum output current of a parallel battery pack according to claim 1, wherein: The calculating the theoretical current value corresponding to each single cell based on the target current value corresponding to each single cell and the target internal resistance corresponding to each single cell includes: For each of the single cells, Determine the theoretical current intermediate value corresponding to the single battery; wherein, is the theoretical current median value corresponding to the single cell, Representative parallel battery packs include Single battery, Indicates the The target internal resistance of each single cell, is the target internal resistance of the single cell, For the Target current value of each single cell; Based on the target internal resistance of each single cell, a theoretical current value is matched for each single cell in the intermediate value of each theoretical current; the theoretical current value corresponding to each single cell is negatively correlated with the target internal resistance corresponding to each single cell.

7. The method for calculating the maximum output current of a parallel battery pack according to claim 1, wherein: The calculating of the output current reduction factor based on the target current value and the theoretical current value of each single battery includes: For each of the single cells, comparing the target current value corresponding to the single cell with the theoretical current value, and if the theoretical current value is greater than the target current value, determining that the single cell is a target single cell; Adding the target current values ​​of the target single cells to obtain a sum of first current values, and adding the theoretical current values ​​of the target single cells to obtain a sum of second current values; A ratio of the sum of the first current values ​​to the sum of the second current values ​​is determined as the output current reduction factor.

8. A device for calculating the maximum output current of a parallel battery pack, characterized in that: include: An acquisition module, configured to acquire the lowest temperature among the temperatures corresponding to the individual cells in the parallel battery pack; a first calculation module configured to obtain, for each of the single cells, a remaining charge of the single cell and a first current value of the single cell, and calculate a current target current value of the single cell based on the minimum temperature, the remaining charge, and the first current value; wherein the first current value is a result of a previous calculation of the target current value of the single cell; a second calculation module, configured to calculate, for each of the single cells, a target internal resistance of the single cell based on a target current value and a remaining charge of the single cell; a third calculation module, configured to calculate, for each of the single cells, a theoretical current value of the single cell based on a target current value of the single cell and a target internal resistance of the single cell; a fourth calculation module, configured to calculate an output current reduction factor based on a target current value and a theoretical current value of each of the single cells; A determination module is configured to determine a maximum output current of the parallel battery group based on the output current reduction factor and a target current value of each of the single batteries.

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