Battery pack self-heating system and method

Abstract

This invention discloses a battery pack self-heating system and method belonging to the battery field. [Solution] The system includes a target battery pack for supplying electrical energy, an energy storage module for storing electrical energy released from the target battery pack and charging the target battery pack with the stored electrical energy, a charge / discharge switch group for controlling the on / off switching of the charge / discharge circuit between the target battery pack and the energy storage module, a detection module for detecting the voltage of each sub-battery pack, the voltage of the energy storage module, and the battery temperature of the target battery pack, and a control module connected to the detection module and the charge / discharge switch group, respectively, for realizing charging and discharging between the target battery pack and the energy storage module by controlling the charge / discharge switch group based on the voltages of the multiple sub-battery packs, the voltage of the energy storage module, and the battery temperature of the target battery pack. This application realizes self-heating of the target battery pack by charging and discharging between the target battery pack and the energy storage module, and improves the efficiency of battery pack self-heating.

Description

Technical Field

[0001] This application relates to the field of battery technology, and more particularly to a battery pack self-heating system and method.

Background Art

[0002] As one of the main ways of energy supply, batteries are widely applied in the field of automobiles. Under different temperature conditions, the discharge characteristics, service life, etc. of the battery are affected. Especially in a low-temperature environment, the electrical conductivity, electrochemical reaction rate, etc. inside the battery decrease, so the charge and discharge power of the battery deteriorates and the durability decreases. To solve the above problems, when the battery is in a low-temperature environment, the battery temperature can be increased by external heating or internal heating methods to ensure the charge and discharge efficiency of the battery.

[0003] When increasing the battery temperature by internal heating (self-heating), usually, a large number of electrical elements need to be added, and current is passed through a large number of electrical components, and heat is generated by the current and the internal resistance of the electrical elements, thereby realizing the self-heating of the battery pack. Since the internal structure of the battery pack is relatively precise, the addition of a large number of electrical elements not only greatly increases the cost, but also leads to a decrease in the stability during the charge and discharge process of the battery pack, increasing the safety risk during the use of the battery. Therefore, the current efficiency of the self-heating method of the battery pack is poor.

Summary of the Invention

Means for Solving the Problems

[0004] This application provides a battery pack self-heating system and method, which can improve the efficiency of battery pack self-heating. The technical solution is as follows.

[0005] In one aspect, relating to a battery pack self-heating system, the system includes a target battery pack for supplying electrical energy, comprising a plurality of sub-battery packs; an energy storage module for storing electrical energy released from the target battery pack and for charging the target battery pack with the stored electrical energy; a charge / discharge switch group connected between the target battery pack and the energy storage module for controlling the on / off state of the charge / discharge circuit between the target battery pack and the energy storage module; a detection module connected to the target battery pack and the energy storage module, respectively, for detecting the voltage of each of the plurality of sub-battery packs, the voltage of the energy storage module, and the battery temperature of the target battery pack; and a control module connected to the detection module and the charge / discharge switch group, respectively, for controlling the charge / discharge switch group based on the voltages of the plurality of sub-battery packs, the voltage of the energy storage module, and the battery temperature of the target battery pack, thereby enabling charging and discharging between the target battery pack and the energy storage module.

[0006] As one option, the charge / discharge switch group includes a plurality of switches, wherein the positive terminal of each sub-battery pack is connected to one of the switches, the other end of the switch is connected to one end of the energy storage module, the negative terminal of each sub-battery pack is connected to one of the switches, the other end of the switch is connected to the other end of the energy storage module, one of the switches is connected between two adjacent sub-battery packs among the plurality of sub-battery packs, and the control module controls the on / off state of the charge / discharge circuit between a single sub-battery pack among the plurality of sub-battery packs and the energy storage module by controlling the on / off state of the plurality of switches, or controls the on / off state of the charge / discharge circuit between the series path of the plurality of sub-battery packs and the energy storage module.

[0007] In another aspect, relating to a battery pack self-heating method applicable to the above system, the method includes: obtaining the battery temperature of the target battery pack using the detection module; if the battery temperature of the target battery pack is less than a first temperature threshold, obtaining the voltages of a plurality of sub-battery packs included in the target battery pack and the voltage of the energy storage module using the detection module; controlling the charge / discharge switch group based on the voltages of the plurality of sub-battery packs and the voltage of the energy storage module to turn on the charge / discharge circuit between the target battery pack and the energy storage module; detecting the battery temperature of the target battery pack using the detection module during the charging and discharging process between the target battery pack and the energy storage module; and if it is detected that the battery temperature of the target battery pack is greater than or equal to a second temperature threshold, controlling the charge / discharge switch group to turn off the charge / discharge circuit between the target battery pack and the energy storage module, wherein the second temperature threshold is greater than the first temperature threshold.

[0008] One option is to control the charge / discharge switch group based on the voltages of the multiple sub-battery packs and the voltage of the energy storage module to turn on the charge / discharge circuit between the target battery pack and the energy storage module. This involves determining the first sub-battery pack with the highest voltage among the multiple sub-battery packs, and if the voltage of the first sub-battery pack is higher than the voltage of the energy storage module, and the difference between the voltage of the first sub-battery pack and the voltage of the energy storage module is greater than a first voltage threshold, then controlling the charge / discharge switch group to enable the energy storage between the multiple sub-battery packs. The method includes: cyclically charging the storage module; controlling the charge / discharge switch group to connect the plurality of sub-battery packs in series and charge the energy storage module if the absolute value of the difference between the voltage of the first sub-battery pack and the voltage of the energy storage module is less than or equal to the first voltage threshold; and controlling the charge / discharge switch group to cycle-charge the plurality of sub-battery packs by the energy storage module if the voltage of the first sub-battery pack is lower than the voltage of the energy storage module and the difference between the voltage of the energy storage module and the voltage of the first sub-battery pack is greater than the first voltage threshold.

[0009] As one option, the plurality of sub-battery packs include two sub-battery packs, and the energy storage module is cycle-charged by the plurality of sub-battery packs by controlling the charge / discharge switch group, the first sub-battery pack is designated as the discharge sub-battery pack, a discharge loss voltage threshold corresponding to the discharge sub-battery pack is determined based on the voltages of the plurality of sub-battery packs, and the energy storage module is charged by the discharge sub-battery pack by controlling the switch connected to the positive and negative terminals of the discharge sub-battery pack in the charge / discharge switch group to turn on and the other switches to turn off, and in the process of the discharge sub-battery pack charging the energy storage module, the detection module detects the target battery - Includes detecting the battery temperature of the battery pack, the temperature rise rate of the battery temperature of the target battery pack, and the discharge loss voltage of the discharge sub-battery pack; and if it is detected that the battery temperature of the target battery pack is below the second temperature threshold, the temperature rise rate of the battery temperature of the target battery pack is equal to or greater than the rate threshold, and the discharge loss voltage of the discharge sub-battery pack is equal to or greater than the discharge loss voltage threshold, then setting another sub-battery pack as the discharge sub-battery pack, and returning to the step of determining the discharge loss voltage threshold corresponding to the discharge sub-battery pack based on the voltages of the plurality of sub-battery packs until the battery temperature of the target battery pack becomes equal to or greater than the second temperature threshold, or the temperature rise rate of the battery temperature falls below the rate threshold.

[0010] As one option, during the process in which the discharging sub-battery pack charges the energy storage module, the detection module detects the battery temperature of the target battery pack, the temperature rise rate of the target battery pack, and the discharge loss voltage of the discharging sub-battery pack. The method further includes, if it is detected that the battery temperature of the target battery pack is below the second temperature threshold and the temperature rise rate of the target battery pack is below the rate threshold, controlling the charge / discharge switch group to connect the plurality of sub-battery packs in series to charge the energy storage module.

[0011] As one option, the charging and discharging switch group is controlled to connect the multiple sub-battery packs in series and charge the energy storage module, which includes controlling the switch in the series path of the multiple sub-battery packs to turn on and the other switches to turn off, thereby connecting the multiple sub-battery packs in series and charging the energy storage module; during the process of connecting the multiple sub-battery packs in series and charging the energy storage module, the detection module detects the battery temperature of the target battery pack and the temperature rise rate of the target battery pack; and if it is detected that the battery temperature of the target battery pack is below the second temperature threshold and the temperature rise rate of the target battery pack is equal to or greater than the rate threshold, the multiple sub-battery packs are connected in series and continue to charge the energy storage module until the battery temperature of the target battery pack becomes equal to or greater than the second temperature threshold, or the temperature rise rate of the battery temperature falls below the rate threshold.

[0012] As one option, in the process of the plurality of sub-battery packs being connected in series to charge the energy storage module, the detection module detects the battery temperature of the target battery pack and the temperature rise rate of the target battery pack. The method further includes controlling the charge / discharge switch group to cycle charge the plurality of sub-battery packs by the energy storage module if it is detected that the battery temperature of the target battery pack is below the second temperature threshold and the temperature rise rate of the target battery pack is below the rate threshold.

[0013] As one option, the plurality of sub-battery packs include two sub-battery packs, and the energy storage module cycle-charges the plurality of sub-battery packs by controlling the charge / discharge switch group, which involves determining the second sub-battery pack with the lowest voltage among the plurality of sub-battery packs, designating the second sub-battery pack as the charging sub-battery pack, determining a charge rise voltage threshold corresponding to the charging sub-battery pack based on the voltage of the energy storage module and the voltage of the charging sub-battery pack, and charging the charging sub-battery pack by controlling the switch connected to the positive and negative terminals of the charging sub-battery pack in the charge / discharge switch group to turn on and the other switches to turn off, and in the process of the energy storage module charging the charging sub-battery pack, The detection module includes detecting the battery temperature of the target battery pack, the temperature rise rate of the target battery pack, and the charge rise voltage of the charging sub-battery pack; and if it is detected that the battery temperature of the target battery pack is below the second temperature threshold, the temperature rise rate of the target battery pack is equal to or greater than the rate threshold, and the charge rise voltage of the charging sub-battery pack is equal to or greater than the charge rise voltage threshold, then another sub-battery pack is designated as the charging sub-battery pack, and the process returns to the step of determining the charge rise voltage threshold corresponding to the charging sub-battery pack based on the voltage of the energy storage module and the voltage of the charging sub-battery pack until the battery temperature of the target battery pack becomes equal to or greater than the second temperature threshold, or the temperature rise rate of the battery temperature falls below the rate threshold.

[0014] As one option, during the process in which the energy storage module charges the charging sub-battery pack, the detection module detects the battery temperature of the target battery pack, the temperature rise rate of the battery temperature of the target battery pack, and the charge rise voltage of the charging sub-battery pack. The method further includes controlling the charge / discharge switch group to cycle charge the energy storage module with the plurality of sub-battery packs if it is detected that the battery temperature of the target battery pack is below the second temperature threshold and the temperature rise rate of the battery temperature of the target battery pack is below the rate threshold.

[0015] As one option, the method involves determining the difference between the maximum and minimum voltages of the plurality of sub-battery packs; determining a voltage change threshold based on the voltage of the energy storage module, the maximum and minimum voltages, if the difference is greater than a second voltage threshold; controlling the charge / discharge switch group to turn on the charge / discharge circuit between the target battery pack and the energy storage module; and detecting the voltage change of the plurality of sub-battery packs using the detection module during the charge / discharge process between the target battery pack and the energy storage module. The further includes, when it is detected that the changing voltage of the plurality of sub-battery packs is greater than or equal to the voltage change threshold, controlling the charge / discharge switch group to turn off the charge / discharge circuit between the target battery pack and the energy storage module.

[0016] In another aspect, with respect to a vehicle, the vehicle includes a memory and a controller, the memory being used to store a computer program, and the controller being used to implement the steps of the battery pack self-heating method by executing the computer program stored in the memory.

[0017] In another aspect, with respect to a computer-readable storage medium, the steps of the battery pack self-heating method are realized when a computer program is stored in the storage medium and the computer program is executed by a controller.

[0018] In another aspect, with respect to a computer program product that includes instructions, if the instructions are being executed on a computer, the computer is made to perform the steps of the battery pack self-heating method described above.

[0019] The beneficial effects of the proposed technology in this application include at least the following:

[0020] The detection module detects the voltage of the sub-battery packs, the voltage of the energy storage module, and the battery temperature of the target battery pack in the target battery pack, and determines whether self-heating is necessary based on the battery temperature of the target battery pack. If it is determined that self-heating of the battery pack is necessary, the charging and discharging of the target battery pack is performed by controlling the on / off state of the charge / discharge switch group between the target battery pack and the energy storage module based on the voltage of each sub-battery pack and the voltage of the energy storage module, thereby achieving self-heating of the target battery pack through charging and discharging between the target battery pack and the energy storage module. The battery pack self-heating method according to this application does not require the addition of a large number of electrical elements, saving costs, improving the stability of the target battery pack during the charging and discharging process, and improving the safety of the battery pack self-heating process. [Brief explanation of the drawing]

[0021] To more clearly explain the technical solutions in the embodiments of this application, the drawings used in the following description of the embodiments will be briefly described below. The drawings in the following description are only some embodiments of this application, and it is obvious to those skilled in the art that based on these drawings, other drawings can be obtained without creative labor.

[0022] [Figure 1] It is a schematic diagram of a battery pack self-heating system according to an embodiment of this application. [Figure 2] It is a schematic diagram of another battery pack self-heating system according to an embodiment of this application. [Figure 3] It is a flowchart of a battery pack self-heating method according to an embodiment of this application. [Figure 4] It is a flowchart of another battery pack self-heating method according to an embodiment of this application. [Figure 5] It is a flowchart of another battery pack self-heating method according to an embodiment of this application. [Figure 6] It is a flowchart of another battery pack self-heating method according to an embodiment of this application. [Figure 7] It is a flowchart of another battery pack self-heating method according to an embodiment of this application. [Figure 8] It is a flowchart of another battery pack self-heating method according to an embodiment of this application. [Figure 9] It is a schematic diagram of the configuration of a vehicle according to an embodiment of this application.

Modes for Carrying Out the Invention

[0023] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the embodiments of this application will be described in more detail below with reference to the drawings.

[0024] Referring to Figure 1, Figure 1 is a schematic diagram of a battery pack self-heating system shown in one exemplary embodiment. The battery pack self-heating system includes a target battery pack 101, an energy storage module 102, a charge / discharge switch group 103, a detection module 104, and a control module 105.

[0025] Here, the target battery pack 101 includes multiple sub-battery packs and is used to supply electrical energy. The energy storage module 102 is used to store the electrical energy released from the target battery pack 101 and to charge the target battery pack 101 with the stored electrical energy. The charge / discharge switch group 103 is connected between the target battery pack 101 and the energy storage module 102 and is used to control the on / off state of the charge / discharge circuit between the target battery pack 101 and the energy storage module 102. The detection module 104 is connected to the target battery pack 101 and the energy storage module 102, respectively, and is used to detect the voltage of each of the multiple sub-battery packs, the voltage of the energy storage module 102, and the battery temperature of the target battery pack 101. The control module 105 is connected to the detection module 104 and the charge / discharge switch group 103, respectively, and is used to achieve charging and discharging between the target battery pack 101 and the energy storage module 102 by controlling the charge / discharge switch group 103 based on the voltages of the multiple sub-battery packs, the voltage of the energy storage module 102, and the battery temperature of the target battery pack 101.

[0026] The target battery pack 101 may be a vehicle's power battery pack, and may include multiple batteries. By separating these multiple batteries, multiple sub-battery packs can be obtained.

[0027] The classification principles and number of sub-battery packs can be determined based on usage needs. For example, the target battery pack 101 can be divided into two sub-battery packs. For instance, a group of sub-batteries on one side of the target battery pack 101, for example, on the left side of the target battery pack 101, can be designated as the first sub-battery pack, and a group of sub-batteries on the other side of the target battery pack, for example, on the right side of the target battery pack 101, can be designated as the second sub-battery pack.

[0028] In the battery pack self-heating scenario, the target battery pack 101 is primarily used to supply electrical energy to the energy storage module 102, thereby increasing the battery temperature of the target battery pack 101 through electron movement.

[0029] The energy storage module 102 may be any component capable of storing and releasing electrical energy. For example, the energy storage module 102 may be a single large-capacity capacitor that achieves the storage and release of electrical energy.

[0030] In some embodiments, the charge / discharge switch group 103 includes a plurality of switches, where the positive terminal of each sub-battery pack is connected to one switch, the other end of which is connected to one end of the energy storage module 102; the negative terminal of each sub-battery pack is connected to one switch, the other end of which is connected to the other end of the energy storage module 102; and one switch is connected between two adjacent sub-battery packs among the plurality of sub-battery packs. The control module 105 controls the on / off state of the charge / discharge circuit between a single sub-battery pack among the plurality of sub-battery packs and the energy storage module 102 by controlling the on / off state of the plurality of switches, or controls the on / off state of the charge / discharge circuit between the series path of the plurality of sub-battery packs and the energy storage module 102.

[0031] Exemplary, as shown in Figure 2, the target battery pack includes sub-battery pack 11 and sub-battery pack 12, and the charge / discharge switch group includes five switches: SP1, SP2, SP3, SP4, and SS1. The positive terminal of sub-battery pack 11 is connected to one end of switch SP1, the positive terminal of sub-battery pack 12 is connected to one end of switch SP3, and the other ends of switches SP1 and SP3 are connected to one end of the energy storage module 102. The negative terminal of sub-battery pack 11 is connected to one end of switch SP2, the negative terminal of sub-battery pack 12 is connected to one end of switch SP4, and the other ends of switches SP2 and SP4 are connected to the other end of the energy storage module 102. Switch SS1 is connected between the negative terminal of sub-battery pack 11 and the positive terminal of sub-battery pack 12.

[0032] The switch may be a high-frequency switch, which can enable high-speed on / off switching of circuits between sub-battery packs and circuits between sub-battery packs and energy storage modules. Control of the high-frequency switch by the control module 105 also generates heat in the circuit, promoting a rise in the battery temperature of the target battery pack 101.

[0033] The detection module 104 may include a voltage sensor for detecting the core voltage of each sub-battery pack and the voltage of the energy storage module 101, and the detection module 104 may further include a temperature sensor for detecting the battery temperature of the target battery pack 101.

[0034] The control module 105 described above may be the main implementer of the battery pack self-heating method in the embodiment of this application. The control module 105 may be a general-purpose CPU (Central Processing Unit), an NP (Network Processor), a microprocessor, or one or more integrated circuits for implementing the technical proposal of this application, such as an ASIC (Application-Specific Integrated Circuit), a PLD (Programmable Logic Device), or a combination thereof. The PLD may be a CPLD (Complex Programmable Logic Device), an FPGA (Field-Programmable Gate Array), a GAL (Generic Array Logic), or any combination thereof.

[0035] Those skilled in the art should understand that the target battery pack 101, energy storage module 102, charge / discharge switch group 103, detection module 104, and control module 105 described above are merely examples, and that other existing or future battery packs, energy storage modules, charge / discharge switch groups, detection modules, or control modules applicable to the embodiments of this application should be included within the scope of protection of the embodiments of this application and are incorporated herein by reference.

[0036] The implementation environment described in the embodiments of this application is intended to provide a clearer explanation of the technical solution of the embodiments of this application, and does not limit the technical solution provided by the embodiments of this application. Those skilled in the art will know that, as the implementation environment changes, the technical solution provided by the embodiments of this application can be similarly applied to similar technical problems.

[0037] Next, the battery pack self-heating method according to the embodiment of this application will be described in detail.

[0038] Figure 3 is a flowchart of a battery pack self-heating method according to an embodiment of this application, which is applied to the control module described above. Referring to Figure 3, the method includes the following steps.

[0039] In step 301, the detection module obtains the battery temperature of the target battery pack.

[0040] In some embodiments, the detection module can acquire the battery temperature of the target battery pack in real time and transmit the acquired battery temperature in real time to the control module.

[0041] The battery temperature of the target battery pack refers to the core temperature of the target battery pack. For example, the detection module may include temperature sensors connected to the core of each sub-battery pack within the target battery pack, allowing it to acquire the core temperature of each sub-battery pack.

[0042] In some embodiments, the detection module may use the average temperature of multiple core temperatures corresponding to multiple sub-battery packs as the battery temperature of the target battery pack and obtain the battery temperature of the target battery pack based on the core temperature of each sub-battery pack, or it may obtain the battery temperature of the target battery pack based on the core temperature of each sub-battery pack using a pre-configured temperature algorithm.

[0043] In step 302, if the battery temperature of the target battery pack is below the first temperature threshold, the detection module obtains the voltages of the multiple sub-battery packs included in the target battery pack and the voltage of the energy storage module.

[0044] If the target battery pack's battery temperature is below a first temperature threshold, it indicates that the target battery pack's current battery temperature is low, the target battery pack's charge / discharge power will decrease, and therefore the target battery pack needs to start self-heating (i.e., control the charging and discharging between the target battery pack and the energy storage module).

[0045] In some embodiments, the voltage of the sub-battery pack refers to the core voltage of the sub-battery pack, and the voltage of the energy storage module refers to the core voltage of the energy storage module. For example, the detection module may include a voltage sensor connected to the core of each sub-battery pack to obtain the core voltage of each sub-battery pack, and a voltage sensor connected to the core of the energy storage module to obtain the core voltage of the energy storage module.

[0046] In some other embodiments, the voltage of the sub-battery pack may refer to the voltage across the sub-battery pack, and the voltage of the energy storage module may refer to the voltage across the energy storage module. For example, for any sub-battery pack, the detection module may detect the voltage across the sub-battery pack.

[0047] In some embodiments, it is also possible to determine whether there are safety risks to the target battery pack based on the voltages of multiple sub-battery packs and the energy storage module before the target battery pack self-heats, thereby enhancing safety during the subsequent process of self-heating the target battery pack.

[0048] In some embodiments, the method further includes determining the difference between the maximum and minimum voltages of the plurality of sub-battery packs; determining a voltage change threshold based on the voltage, maximum and minimum voltages of the energy storage module if the difference is greater than a second voltage threshold; turning on the charge / discharge circuit between the target battery pack and the energy storage module by controlling a charge / discharge switch group; detecting the voltage change of the plurality of sub-battery packs using a detection module during the charging and discharging process between the target battery pack and the energy storage module; and turning off the charge / discharge circuit between the target battery pack and the energy storage module by controlling a charge / discharge switch group if it is detected that the voltage change of the plurality of sub-battery packs is greater than or equal to the voltage change threshold.

[0049] Furthermore, if the difference between the maximum and minimum voltages of multiple sub-battery packs is greater than the second voltage threshold, it indicates a large voltage difference between the sub-battery packs, and a safety risk exists during the charging and discharging of the target battery pack. In this case, the safety of the target battery pack can be improved by controlling the ON state of the charging and discharging circuit between the target battery pack and the energy storage module to reduce the maximum voltage within the sub-battery pack or increase the minimum voltage within the sub-battery pack, thereby reducing the voltage difference between the sub-battery packs.

[0050] In some embodiments, as shown in Figure 4, when the maximum voltage is greater than the voltage of the energy storage module, the charge / discharge switch group is controlled to turn on the charge / discharge circuit between the energy storage module and the sub-battery pack with the highest voltage, allowing the energy storage module to be charged by the sub-battery pack with the highest voltage. When the maximum voltage is not greater than the voltage of the energy storage module, i.e., when the maximum voltage is less than or equal to the voltage of the energy storage module, the charge / discharge switch group is controlled to turn on the charge / discharge circuit between the energy storage module and the sub-battery pack with the lowest voltage, allowing the sub-battery pack with the lowest voltage to be charged by the energy storage module.

[0051] Referring to Figure 2, let's take the example where the target battery pack includes two sub-battery packs, the voltage of sub-battery pack 11 is greater than the voltage of sub-battery pack 12, and the difference between the voltages of sub-battery pack 11 and sub-battery pack 12 is greater than a second voltage threshold. If the voltage of sub-battery pack 11 is greater than the voltage of the energy storage module, switches SP1 and SP2 are controlled to turn on, and switches SP3, SP4 and SS1 are controlled to turn off, and the energy storage module is charged by sub-battery pack 11. If the voltage of sub-battery pack 11 is less than or equal to the voltage of the energy storage module, switches SP1, SP2 and SS1 are controlled to turn off, and switches SP3 and SP4 are controlled to turn on, and the energy storage module is charged by sub-battery pack 12.

[0052] When the energy storage module is charged by the sub-battery pack with the highest voltage, the voltage change threshold is the discharge loss voltage threshold. When the energy storage module charges the sub-battery pack with the lowest voltage, the voltage change threshold is the charge rise voltage threshold. When the energy storage module is charged by the sub-battery pack with the highest voltage, and the discharge loss voltage of the sub-battery pack with the highest voltage reaches the discharge loss voltage threshold, the charge / discharge switch group is controlled to turn off the charging circuit between the sub-battery pack with the highest voltage and the energy storage module. Here, the fact that the discharge loss voltage of the sub-battery pack with the highest voltage reaches the discharge loss voltage threshold can be understood as the discharge loss voltage being greater than or equal to the discharge loss voltage threshold. When the energy storage module is charged by the sub-battery pack with the lowest voltage, and the charge rise voltage of the sub-battery pack reaches the charge rise voltage threshold, the charge / discharge switch group is controlled to turn off the charging circuit between the energy storage module and the sub-battery pack with the lowest voltage. Here, the fact that the charge rise voltage of the sub-battery pack with the lowest voltage reaches the charge rise voltage threshold can be understood as the charge rise voltage being greater than or equal to the charge rise voltage threshold.

[0053] The discharge loss voltage threshold and the charge rise voltage threshold can be determined based on the voltage difference between the multiple sub-battery packs, for example, △U = 0.8 * (Umax - Umin), where Umax refers to the maximum voltage among the multiple sub-battery packs, Umin refers to the minimum voltage among the multiple sub-battery packs, and 0.8 refers to the relationship between the discharge loss voltage threshold (or charge rise voltage threshold) and the voltage difference between the sub-battery packs. Specifically, these can be determined according to the actual usage needs, and may be, for example, 0.9 or 0.85.

[0054] In some embodiments, if the voltage of the energy storage module is less than the maximum voltage and greater than the minimum voltage, the discharge loss voltage threshold or charge loss voltage threshold can also be determined by the voltage difference between the maximum voltage and the voltage of the energy storage module, and the voltage difference between the voltage of the energy storage module and the minimum voltage.

[0055] For example, if the voltage of the energy storage module is less than the maximum voltage and greater than the minimum voltage, i.e., if the voltage of the energy storage module is between the maximum and minimum voltages, and assuming the voltage of the energy storage module is 3.5V, and the maximum voltage among the multiple sub-battery packs is 3.8V and the minimum voltage is 3.4V, then the voltage difference between the maximum voltage and the energy storage module voltage is 0.3V, and the voltage difference between the energy storage module voltage and the minimum voltage is 0.1V. This shows that the voltage difference between the energy storage module and the sub-battery pack with the highest voltage is larger than the voltage difference with the sub-battery pack with the lowest voltage, and therefore, the energy storage module is charged by the sub-battery pack with the highest voltage, and the voltage of the sub-battery pack with the highest voltage rapidly increases. A rapid decrease in voltage, i.e., a rapid reduction in the voltage difference between sub-battery packs, can be achieved. Assuming that the voltage of the energy storage module is 3.3V, the maximum voltage among the multiple sub-battery packs is 3.4V, and the minimum voltage is 3.0V, the voltage difference between the maximum voltage and the energy storage module voltage is 0.1V, and the voltage difference between the energy storage module voltage and the minimum voltage is 0.3V. This shows that the voltage difference between the energy storage module and the lowest voltage sub-battery pack is larger than the voltage difference with the highest voltage sub-battery pack. Therefore, the energy storage module can charge the lowest voltage sub-battery pack, resulting in a rapid increase in the voltage of the lowest voltage sub-battery pack, i.e., a rapid decrease in the voltage difference between sub-battery packs.

[0056] The main purpose of the above steps is to ensure that, if the target battery pack needs to raise its temperature through self-heating, the voltage difference between the sub-battery packs is within an acceptable range before the target battery pack self-heats. For example, it is to ensure that the voltage difference between the sub-battery packs is below a second voltage threshold. If the voltage difference between the sub-battery packs is large, it is necessary to first control the voltage difference between the sub-battery packs to an acceptable range, and only then perform charging and discharging between the target battery pack and the energy storage module.

[0057] In some other embodiments, when the voltage difference between sub-battery packs is large, it is not necessary to consider whether the battery temperature of the target battery pack is below a first temperature threshold, but rather to ensure that the battery temperature of the target battery pack is within a safe range, for example, by ensuring that the battery temperature of the target battery pack is below a third temperature threshold. In other words, when the voltage difference between sub-battery packs is large, consideration is first given to reducing the voltage difference between the sub-battery packs, and then to consider whether it is necessary to achieve self-heating of the target battery pack by charging and discharging the target battery pack and the energy storage module.

[0058] Of course, in some other embodiments, after obtaining the voltages of the multiple sub-battery packs and the energy storage module, the self-heating of the target battery pack may be directly achieved, for example by directly performing step 303 below, and the embodiments of this application are not limited thereto.

[0059] In step 303, the charge / discharge circuit between the target battery pack and the energy storage module is turned on by controlling the charge / discharge switch group based on the voltages of the multiple sub-battery packs and the voltage of the energy storage module.

[0060] In some embodiments, the charging and discharging circuit between the target battery pack and the energy storage module can be turned on by controlling the charge / discharge switch group in steps (1) to (4) below, based on the voltages of the multiple sub-battery packs and the voltage of the energy storage module.

[0061] (1) From among the multiple sub-battery packs, determine the first sub-battery pack with the highest voltage.

[0062] (2) When the voltage of the first sub-battery pack is higher than the voltage of the energy storage module, and the difference between the voltage of the first sub-battery pack and the voltage of the energy storage module is greater than the first voltage threshold, the energy storage module is cycle-charged by the multiple sub-battery packs by controlling the charge / discharge switch group.

[0063] When the voltage of the first sub-battery pack is higher than the voltage of the energy storage module, and the voltage difference between the first sub-battery pack and the energy storage module is greater than the first voltage threshold, it indicates that the voltage of the first sub-battery pack is sufficiently high relative to the voltage of the energy storage module. This results in a larger current when the first sub-battery pack charges the energy storage module, ensuring that sufficient heat is generated during charging and discharging, leading to a faster temperature rise rate of the target battery pack, i.e., a higher self-heating efficiency of the target battery pack. Therefore, when the voltage of the first sub-battery pack is higher than the voltage of the energy storage module, and the voltage difference between the first sub-battery pack and the energy storage module is greater than the first voltage threshold, a single sub-battery pack can charge the energy storage module to achieve a rapid temperature rise of the target battery pack.

[0064] In some embodiments, as shown in Figure 5, where Umax refers to the maximum voltage among the multiple sub-battery packs, i.e., the voltage of the first sub-battery pack, Uc refers to the voltage of the energy storage module, and d refers to the first voltage threshold, and the multiple sub-battery packs include two sub-battery packs. In this case, the first sub-battery pack is designated as the discharge sub-battery pack, and based on the voltages of the multiple sub-battery packs, a discharge loss voltage threshold corresponding to the discharge sub-battery pack is determined. The energy storage module is charged by the discharge sub-battery pack by controlling the switch connected to the positive and negative terminals of the discharge sub-battery pack in the charge / discharge switch group to turn on and the other switches to turn off. During the process in which the discharge sub-battery pack charges the energy storage module, the detection module detects the battery temperature of the target battery pack, the temperature rise rate of the target battery pack, and the discharge loss voltage of the discharge sub-battery pack. If it is detected that the battery temperature of the target battery pack is below the second temperature threshold, the temperature rise rate of the target battery pack is equal to or greater than the rate threshold, and the discharge loss voltage of the discharge sub-battery pack is equal to or greater than the discharge loss voltage threshold, another sub-battery pack is designated as the discharge sub-battery pack, and the process returns to the step of determining the discharge loss voltage threshold corresponding to the discharge sub-battery pack based on the voltages of the multiple sub-battery packs until the battery temperature of the target battery pack becomes equal to or greater than the second temperature threshold, or the temperature rise rate of the battery temperature falls below the rate threshold.

[0065] During the process of charging the energy storage module with a discharge sub-battery pack, as the charging time increases, the voltage of the discharge sub-battery pack gradually decreases, i.e., voltage loss occurs in the discharge sub-battery pack. Because the voltage loss of the discharge sub-battery pack becomes large, the voltage difference between sub-battery packs becomes large, and in order to avoid a safety risk during self-heating, in the embodiment of this application, a discharge loss voltage threshold can be set based on the voltages of multiple sub-battery packs. If the single discharge loss voltage of a discharge sub-battery pack is greater than or equal to the discharge loss voltage threshold, the sub-battery pack other than the currently discharging sub-battery pack is used as the discharge sub-battery pack and discharges to the energy storage module, thereby enabling multiple sub-battery packs to cycle-charge the energy storage module. In other words, by having multiple sub-battery packs alternately charge the energy storage module, voltage loss can be alternately generated in multiple sub-battery packs. This avoids a safety risk that may arise when the sub-battery packs charge the energy storage module, due to a large single voltage loss in one sub-battery pack causing a large voltage difference between sub-battery packs.

[0066] JPEG2026509981000013.jpg96170

[0067] Note that 0.8 in Equation 1 refers to the relationship between the discharge loss voltage threshold and the voltage difference between the sub-battery packs. This relationship can be selected according to actual usage needs, and may be, for example, 1.3 times, 1.7 times, or 2 times.

[0068] The temperature rise rate of a target battery pack can be determined based on the change in the battery temperature of the target battery pack. For example, the temperature rise rate of a target battery pack can be determined based on the temperature rise of the target battery pack within a target time. Here, the target time can be flexibly determined based on actual usage needs, for example, within 2 seconds, within 1 second, etc., and the specific unit of the temperature rise rate can be selected according to actual usage needs, for example, degrees Celsius per second, degrees Fahrenheit per minute, etc.

[0069] Referring to Figure 2, assuming that the target battery pack includes sub-battery pack 11 and sub-battery pack 12, and that the voltage of sub-battery pack 11 is greater than the voltage of sub-battery pack 12, when sub-battery pack 11 is used as a discharge sub-battery pack, switches SP1 and SP2 are controlled to turn on, and switches SP3, SP4 and SS1 are controlled to turn off, thereby charging the energy storage module with sub-battery pack 11 as a discharge sub-battery pack. Until the discharge loss voltage of sub-battery pack 11 is greater than or equal to the discharge loss voltage threshold, and the battery temperature of the target battery pack remains below the second temperature threshold, and the temperature rise rate of the battery temperature of the target battery pack remains above the rate threshold, switches SP1, SP2 and SS1 are controlled to turn off, and switches SP3 and SP4 are controlled to turn on, thereby charging the energy storage module with sub-battery pack 12 as a discharge sub-battery pack. This realizes the cyclic charging of the energy storage module by multiple sub-battery packs.

[0070] As can be seen from Figure 5, the cycle conditions for multiple sub-battery packs to cycle-charge the energy storage module are that the battery temperature of the target battery pack is below the second temperature threshold, and the rate of temperature rise of the target battery pack during the cycle is continuously above the rate threshold. Here, if the battery temperature of the target battery pack is above the second temperature threshold, the temperature of the target battery pack satisfies the conditions, so the self-heating of the target battery pack can be terminated directly. If the rate of temperature rise of the target battery pack is below the rate threshold, then the multiple sub-battery packs cannot rapidly raise the temperature of the target battery pack by cycle-charging the energy storage module, and therefore the multiple sub-battery packs can terminate the cycle-charging of the energy storage module.

[0071] In other words, if the target battery pack temperature is above the second temperature threshold, it indicates that the battery temperature of the target battery pack no longer adversely affects the charge and discharge power to the outside of the target battery pack, and therefore the self-heating of the target battery pack can be terminated.

[0072] As the sub-battery pack continuously charges the energy storage module cyclically, the voltage of the sub-battery pack gradually decreases, and the voltage of the energy storage module gradually increases. This causes the voltage difference between the sub-battery pack and the energy storage module to gradually decrease. In this case, the decrease in the voltage difference reduces the current in the charging circuit, which in turn reduces the heat generated in the charging circuit and lowers the temperature rise rate of the target battery pack. If the temperature rise rate of the target battery pack is below the rate threshold, it indicates that the voltage of the sub-battery pack and the voltage of the energy storage module are approaching. If self-heating of the target battery pack continues in this manner, the temperature rise rate of the target battery pack will only decrease further. In this case, it is necessary to adjust the charging and discharging method between the target battery pack and the energy storage module in order to improve the self-heating efficiency of the target battery pack.

[0073] In some embodiments, as shown in Figure 5, when it is detected that the battery temperature of the target battery pack is below a second temperature threshold and the temperature rise rate of the target battery pack is below a rate threshold, the charge / discharge switch group can be controlled to connect the multiple sub-battery packs in series and charge the energy storage module. The process of connecting the multiple sub-battery packs in series and charging the energy storage module will be explained in detail in step (3) below and will not be explained here.

[0074] (3) If the absolute value of the difference between the voltage of the first sub-battery pack and the voltage of the energy storage module is less than or equal to the first voltage threshold, the charge / discharge switch group is controlled so that the multiple sub-battery packs are connected in series and the energy storage module is charged.

[0075] If the absolute value of the difference between the voltage of the first sub-battery pack and the voltage of the energy storage module is less than or equal to the first voltage threshold, it indicates that the voltages of the first sub-battery pack and the energy storage module are close together. In this case, whether the energy storage module is charged by the first sub-battery pack or the first sub-battery pack is charged by the energy storage module, the voltage difference between the two is small, resulting in a small current in the charging circuit and less heat generated during charging and discharging. This slows down the temperature rise rate of the target battery pack, meaning the self-heating efficiency of the target battery pack is low and it cannot meet the demand for rapid temperature rise of the target battery pack.

[0076] In this case, considering the principle of increasing voltage by connecting batteries in series, connecting multiple sub-battery packs in series ensures that the overall voltage of the target battery pack becomes sufficiently large compared to the voltage of the energy storage module. This guarantees that the current in the charge / discharge circuit is sufficiently large, and that sufficient heat is generated during charging and discharging, resulting in a faster temperature rise rate of the target battery pack, i.e., a higher self-heating efficiency of the target battery pack.

[0077] In some embodiments, as shown in Figure 6, the multiple sub-battery packs are connected in series to charge the energy storage module by controlling the switches in the series path of the multiple sub-battery packs to turn on and the other switches to turn off. During the process of the multiple sub-battery packs being connected in series to charge the energy storage module, the detection module detects the battery temperature of the target battery pack and the temperature rise rate of the target battery pack. If it is detected that the battery temperature of the target battery pack is below a second temperature threshold and the temperature rise rate of the target battery pack is equal to or greater than the rate threshold, the multiple sub-battery packs are connected in series to continue charging the energy storage module until the battery temperature of the target battery pack becomes equal to or greater than the second temperature threshold, or until the temperature rise rate of the battery temperature falls below the rate threshold.

[0078] Referring to Figure 2, when sub-battery pack 11 and sub-battery pack 12 are connected in series to charge the energy storage module, switch SP1, switch SS1 and switch SP4 are turned on, and switch SP2 and switch SP 3 By controlling it to turn off, the sub-battery pack 11 and the sub-battery 12 are connected in series to charge the energy storage module.

[0079] As can be seen from Figure 6, the conditions for charging the energy storage module by connecting multiple sub-battery packs in series are that the battery temperature of the target battery pack is below the second temperature threshold, and the rate of temperature rise of the target battery pack during the cycle is continuously above the rate threshold. Here, if the battery temperature of the target battery pack is above the second temperature threshold, the temperature of the target battery pack satisfies the conditions, so the self-heating of the target battery pack can be terminated directly. If the rate of temperature rise of the target battery pack is below the rate threshold, then the target battery pack cannot be rapidly heated by charging the energy storage module by connecting multiple sub-battery packs in series, so the charging of the energy storage module by connecting multiple sub-battery packs in series can be terminated.

[0080] In other words, if the target battery pack temperature is above the second temperature threshold, it indicates that the battery temperature of the target battery pack no longer adversely affects the charge and discharge power to the outside of the target battery pack, and therefore the self-heating of the target battery pack can be terminated.

[0081] As the sub-battery packs are connected in series and continuously charge the energy storage module, the overall voltage of the series-connected sub-battery packs gradually decreases, while the voltage of the energy storage module gradually increases. This causes the voltage difference between the series-connected sub-battery packs and the energy storage module to gradually decrease. In this case, the decrease in voltage difference reduces the current in the charging circuit, which in turn reduces the heat generated in the charging circuit and lowers the temperature rise rate of the target battery pack. If the temperature rise rate of the target battery pack is below the rate threshold, it indicates that the overall voltage of the series-connected sub-battery packs and the voltage of the energy storage module are approaching. If self-heating of the target battery pack continues in this manner, the temperature rise rate of the target battery pack will only decrease further. In this case, the charging and discharging method between the target battery pack and the energy storage module needs to be adjusted to improve the self-heating efficiency of the target battery pack.

[0082] In some embodiments, as shown in Figure 6, when it is detected that the battery temperature of the target battery pack is below a second temperature threshold and the temperature rise rate of the target battery pack is below a rate threshold, the energy storage module can cycle-charge the multiple sub-battery packs by controlling the charge / discharge switch group. Here, the cycling charge of the multiple sub-battery packs by the energy storage module will be explained in detail in step (4) below and will not be explained here.

[0083] (4) If the voltage of the first sub-battery pack is lower than the voltage of the energy storage module, and the difference between the voltage of the energy storage module and the voltage of the first sub-battery pack is greater than the first voltage threshold, the energy storage module cycle-charges the multiple sub-battery packs by controlling the charge / discharge switch group.

[0084] In some embodiments, as shown in Figure 7, the plurality of sub-battery packs include two sub-battery packs. In this case, the second sub-battery pack with the lowest voltage can be determined from among the plurality of sub-battery packs, and the second sub-battery pack is designated as the charging sub-battery pack. Based on the voltage of the energy storage module and the voltage of the charging sub-battery pack, a charging rise voltage threshold corresponding to the charging sub-battery pack is determined, and the energy storage module charges the charging sub-battery pack by controlling the switch connected to the positive and negative terminals of the charging sub-battery pack in the charge / discharge switch group to turn on and the other switches to turn off. During the process in which the energy storage module charges the charging sub-battery pack, the detection module detects the battery temperature of the target battery pack, and the target battery pack The temperature rise rate of the target battery pack and the charging voltage rise of the charging sub-battery pack are detected. If it is detected that the target battery pack's battery temperature is below the second temperature threshold, the target battery pack's temperature rise rate is equal to or greater than the rate threshold, and the charging voltage rise of the charging sub-battery pack is equal to or greater than the charging voltage rise threshold, another sub-battery pack is designated as the charging sub-battery pack. The process returns to the step of determining the charging voltage rise threshold corresponding to the charging sub-battery pack based on the voltage of the energy storage module and the voltage of the charging sub-battery pack, until the target battery pack's battery temperature becomes equal to or greater than the second temperature threshold, or the battery temperature rise rate becomes equal to or greater than the rate threshold.

[0085] During the process of charging a sub-battery pack by the energy storage module, the voltage of the charging sub-battery pack gradually increases as the charging time lengthens. As the voltage rise of the charging sub-battery pack becomes larger, the voltage difference between sub-battery packs increases, which can create safety risks. To avoid this, in the embodiments of this application, a charging rise voltage threshold can be set based on the voltages of multiple sub-battery packs. If the voltage of a single charge of a charging sub-battery pack is equal to or greater than the charging rise voltage threshold, the energy storage module charges the charging sub-battery pack, using a sub-battery pack other than the currently discharging sub-battery pack as the charging sub-battery pack. This enables the energy storage module to cycle-charge multiple sub-battery packs, meaning that the energy storage module alternately charges multiple sub-battery packs, allowing the voltages of multiple sub-battery packs to alternately increase. This avoids the safety risks that can arise when the energy storage module charges sub-battery packs, where the voltage of one sub-battery pack rises significantly, causing a large voltage difference between sub-battery packs.

[0086] JPEG2026509981000014.jpg89170

[0087] Note that 1.5 in Equation 2 refers to the relationship between the voltage rise threshold and the voltage difference between the sub-battery packs. This relationship can be selected according to actual usage needs, and may be, for example, 1.3 times, 1.7 times, or 2 times.

[0088] Referring to Figure 2, assuming that the voltage of sub-battery pack 11 is lower than the voltage of sub-battery pack 12, if sub-battery pack 11 is to be used as a charging sub-battery pack, switches SP1 and SP2 are controlled to turn on, and switches SP3, SP4 and SS1 are controlled to turn off, so that sub-battery pack 11 is used as a charging sub-battery pack and charged by the energy storage module, and until the charging rise voltage of sub-battery pack 11 is equal to or greater than the charging rise voltage threshold, if the battery temperature of the target battery pack remains below the second temperature threshold and the temperature rise rate of the battery temperature of the target battery pack remains above the rate threshold, switches SP1, SP2 and SS1 are controlled to turn off, and switches SP3 and SP4 are controlled to turn on, so that sub-battery pack 12, i.e., sub-battery packs other than sub-battery pack 11, is used as a charging sub-battery pack and the energy storage module is charged, thereby achieving cycle charging of sub-battery packs 11 and 12 by the energy storage module.

[0089] As can be seen from Figure 7, the cycle conditions for the energy storage module to cycle-charge sub-battery packs 11 and 12 are that the battery temperature of the target battery pack is below the second temperature threshold, and the rate of temperature rise of the target battery pack during the cycle is continuously above the rate threshold. Here, if the battery temperature of the target battery pack is above the second temperature threshold, the temperature of the target battery pack satisfies the conditions, so the self-heating of the target battery pack can be terminated directly. If the rate of temperature rise of the target battery pack is below the rate threshold, the energy storage module cannot rapidly raise the temperature of the target battery pack by cycle-charging multiple sub-battery packs, so the energy storage module can terminate the cycle-charging of sub-battery packs 11 and 12.

[0090] In other words, if the target battery pack temperature is above the second temperature threshold, it indicates that the battery temperature of the target battery pack no longer adversely affects the charge and discharge power to the outside of the target battery pack, and therefore the self-heating of the target battery pack can be terminated.

[0091] As the energy storage module continuously charges the sub-battery pack cyclically, the voltage of the energy storage module gradually increases, and the voltage of the sub-battery pack gradually increases, causing the voltage difference between the sub-battery pack and the energy storage module to gradually decrease. In this case, the decrease in the voltage difference reduces the current in the charging circuit, which in turn reduces the heat generated in the charging circuit and lowers the temperature rise rate of the target battery pack. If the temperature rise rate of the target battery pack is below the rate threshold, it indicates that the voltage of the sub-battery pack and the voltage of the energy storage module are approaching, and if self-heating of the target battery pack continues in this manner, the temperature rise rate of the target battery pack will only decrease further. In this case, it is necessary to adjust the charging and discharging method between the target battery pack and the energy storage module in order to improve the self-heating efficiency of the target battery pack.

[0092] In some embodiments, as shown in Figure 7, when it is detected that the battery temperature of the target battery pack is below a second temperature threshold and the temperature rise rate of the target battery pack is below a rate threshold, the charge / discharge switch group can be controlled to cycle-charge the energy storage module using the multiple sub-battery packs. Here, the details of cycle-charging the energy storage module using multiple sub-battery packs can be found in the relevant explanation in step (2) above, and are omitted here.

[0093] In step 304, the battery temperature of the target battery pack is detected by the detection module during the charging and discharging process between the target battery pack and the energy storage module.

[0094] In step 305, if it is detected that the battery temperature of the target battery pack is above the second temperature threshold, the charge / discharge switch group is controlled to turn off the charge / discharge circuit between the target battery pack and the energy storage module, and the second temperature threshold is greater than the first temperature threshold.

[0095] In some embodiments, the charging and discharging circuit between the target battery pack and the energy storage module can be turned off by controlling each switch in the charge / discharge switch group to turn off when it is detected that the battery temperature of the target battery pack is above a second temperature threshold.

[0096] Next, the overall technical proposal of the embodiment of this application will be explained using Figure 8. As shown in Figure 8, here Umax refers to the maximum voltage among the voltages of the multiple sub-battery packs, i.e., the voltage of the first sub-battery pack, Uc refers to the voltage of the energy storage module, and d refers to the first voltage threshold. When the battery temperature of the target battery pack is below the first temperature threshold, it is first determined whether the voltage difference between the multiple sub-battery packs in the target battery pack is greater than the second voltage threshold. If the voltage difference between the multiple sub-battery packs is greater than the second voltage threshold, the voltage difference between the multiple sub-battery packs can be reduced, as shown in Figure 4 above.

[0097] If the voltage difference between multiple sub-battery packs is less than or equal to a second voltage threshold, it indicates that the voltage difference between the multiple sub-battery packs of the target battery pack is small. In this case, the first sub-battery pack with the highest voltage among the multiple sub-battery packs can be determined, and different charging and discharging methods are performed by turning multiple switches on or off based on the relative magnitudes of the voltage of the first sub-battery pack and the voltage of the energy storage module.

[0098] If the voltage of the first sub-battery pack is higher than the voltage of the energy storage module, and the difference between the voltage of the first sub-battery pack and the voltage of the energy storage module is greater than the first voltage threshold, or if the energy storage module cycle-charges multiple sub-battery packs and the temperature rise rate of the target battery pack is less than the rate threshold, the energy storage module can be cycle-charged by multiple sub-battery packs as shown in Figure 5 above, and the absolute value of the difference between the voltage of the first sub-battery pack and the voltage of the energy storage module is less than or equal to the first voltage threshold, or if the energy storage module can be cycle-charged by multiple sub-battery packs If the battery is charged and the temperature rise rate of the target battery pack is below the rate threshold, multiple sub-battery packs are connected in series to charge the energy storage module, as shown in Figure 6 above. If the voltage of the first sub-battery pack is lower than the voltage of the energy storage module, and the difference between the voltage of the energy storage module and the voltage of the first sub-battery pack is greater than the first voltage threshold, or if the temperature rise rate of the target battery pack is below the rate threshold during the process of multiple sub-battery packs being connected in series to charge the energy storage module, the energy storage module cycle-charges the multiple sub-battery packs, as shown in Figure 7 above.

[0099] The above self-heating method ensures that the battery temperature of the target battery pack is maintained at a high rate of increase before the battery temperature exceeds a second temperature threshold, i.e., the battery temperature rises at a high rate, thereby achieving a rapid rise in battery temperature and ensuring the self-heating efficiency of the target battery pack. Furthermore, when the sub-battery pack and energy storage module are cycled charge and discharged, the alternating operation of the sub-battery packs, for example, by having multiple sub-battery packs alternately charge the energy storage module, or by having the energy storage module alternately charge multiple sub-battery packs, ensures that when the target battery pack self-heats, the voltage between the sub-battery packs alternately rises or falls, ensuring that the voltage difference between the sub-battery packs is always kept within an acceptable range and ensuring safety and stability during the self-heating process of the target battery pack.

[0100] Figure 9 is a schematic diagram of the configuration of a vehicle according to an embodiment of the present application, the vehicle 900 including a memory 901 and a controller 902, the memory 901 being used to store a computer program, and the controller 902 being used to realize the steps of the battery pack self-heating method by executing the computer program stored in the memory 901.

[0101] The memory 901 may include one or more computer-readable storage media, which may be non-temporary. The memory 901 may also include one or more high-speed random-access memories and non-volatile memories, such as disk storage devices and flash storage devices. In some embodiments, the non-temporary computer-readable storage media in the memory 901 are used to store at least one instruction, which is executed by the controller 902 to realize the battery pack self-heating method according to embodiments of the method of this application.

[0102] The controller 902 may include one or more processing cores, such as a 4-core processor or an 8-core processor. The controller 902 can be implemented by at least one of the following hardware components: a DSP (Digital Signal Processing), an FPGA (Field Programmable Gate Array), or a PLA (Programmable Logic Array). The controller 902 may also include a main processor and a coprocessor, the main processor being a processor for processing data in the startup state and also called a CPU (Central Processing Unit), and the coprocessor being a low-power processor for processing data in the standby state. In some embodiments, the controller 902 may integrate a GPU (Graphics Processing Unit), which is configured to render and draw content that needs to be displayed on a display. In some embodiments, the controller 902 may further include an AI (Artificial Intelligence) processor, which is used to process computational operations related to machine learning.

[0103] Those skilled in the art will understand that the structure shown in Figure 9 is not limiting to terminal 900 and may include more or fewer components than shown, and that several components can be combined or different component arrangements can be adopted.

[0104] In some embodiments, a computer-readable storage medium is further provided, in which a computer program is stored, and the steps of the battery pack self-heating method of the above embodiment are realized when the computer program is executed by a controller. For example, the computer-readable storage medium may be ROM, RAM, CD-ROM, magnetic tape, floppy disk, and optical data storage device.

[0105] Furthermore, the computer-readable storage medium according to the embodiment of this application may be a non-volatile storage medium, or in other words, a non-temporary storage medium.

[0106] It should be understood that all or some of the steps to realize the above embodiment can be implemented by software, hardware, firmware, or any combination thereof. When implemented using software, it can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. The computer instructions can be stored on the computer-readable storage medium.

[0107] In other words, in some embodiments, a computer program product including instructions is further provided, which, when running on a computer, causes the computer to perform the steps of the battery pack self-heating method described above.

[0108] It should be understood that, as used herein, “at least one” means one or more, and “multiple” means two or more. In the description of the embodiments of this application, unless otherwise specified, “ / ” means “or,” for example, “A / B” can mean “A or B,” and “and / or” in this specification describes the relationship between related objects and indicates that three relationships may exist, for example, A and / or B can indicate three situations: A exists alone, A and B exist simultaneously, and B exists alone. Furthermore, in order to clearly describe the technical concepts of the embodiments of this application, expressions such as “first,” “second,” etc. are used in the embodiments of this application to distinguish identical or similar things that have essentially the same function or operation. Those skilled in the art will understand that expressions such as “first,” “second,” etc. do not limit the number or order of execution, and that expressions such as “first,” “second,” etc. do not necessarily mean that they are different.

[0109] Furthermore, all information (including, but not limited to, user equipment information and user personal information), data (including, but not limited to, analytical data, stored data, and displayed data) and signals relating to the embodiments of this application are authorized by the user or fully authorized by all relevant parties, and the collection, use, and processing of related data must comply with the laws, regulations, and standards of the relevant countries and regions.

[0110] The foregoing is merely an example of what is described herein and does not limit the present application. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application are included within the scope of this application.

Claims

1. A battery pack self-heating system, The aforementioned system, Includes multiple sub-battery packs, a target battery pack for supplying electrical energy, An energy storage module for storing electrical energy released from the target battery pack and for charging the target battery pack with the stored electrical energy, A charge / discharge switch group connected between the target battery pack and the energy storage module for controlling the on / off state of the charge / discharge circuit between the target battery pack and the energy storage module, A detection module connected to the target battery pack and the energy storage module respectively, for detecting the voltage of each of the multiple sub-battery packs, the voltage of the energy storage module, and the battery temperature of the target battery pack, A system comprising a control module connected to the detection module and the charge / discharge switch group, respectively, for controlling the charge / discharge switch group based on the voltages of the plurality of sub-battery packs, the voltage of the energy storage module, and the battery temperature of the target battery pack, thereby enabling charging and discharging between the target battery pack and the energy storage module.

2. The charge / discharge switch group includes a plurality of switches, the positive terminal of each sub-battery pack is connected to one of the switches, the other end of the switch is connected to one end of the energy storage module, the negative terminal of each sub-battery pack is connected to one of the switches, the other end of the switch is connected to the other end of the energy storage module, and one of the switches is connected between two adjacent sub-battery packs among the plurality of sub-battery packs. The control module controls the on / off state of the charge / discharge circuit between a single sub-battery pack among the plurality of sub-battery packs and the energy storage module, or controls the on / off state of the charge / discharge circuit between the series path of the plurality of sub-battery packs and the energy storage module, by controlling the on / off state of the plurality of switches. The system according to feature 1.

3. A battery pack self-heating method applicable to the system described in claim 1 or 2, The aforementioned method, The detection module acquires the battery temperature of the target battery pack, If the battery temperature of the target battery pack is below a first temperature threshold, the detection module obtains the voltages of the multiple sub-battery packs included in the target battery pack and the voltage of the energy storage module. By controlling the charge / discharge switch group based on the voltages of the plurality of sub-battery packs and the voltage of the energy storage module, the charge / discharge circuit between the target battery pack and the energy storage module is turned on. During the charging and discharging process between the target battery pack and the energy storage module, the detection module detects the battery temperature of the target battery pack. A method characterized in that, when it is detected that the battery temperature of the target battery pack is greater than or equal to a second temperature threshold, the charge / discharge switch group is controlled to turn off the charge / discharge circuit between the target battery pack and the energy storage module, wherein the second temperature threshold is greater than the first temperature threshold.

4. To enable the charging and discharging circuit between the target battery pack and the energy storage module by controlling the charge / discharge switch group based on the voltages of the plurality of sub-battery packs and the voltage of the energy storage module, From among the aforementioned multiple sub-battery packs, determine the first sub-battery pack with the highest voltage, When the voltage of the first sub-battery pack is higher than the voltage of the energy storage module, and the difference between the voltage of the first sub-battery pack and the voltage of the energy storage module is greater than the first voltage threshold, the charge / discharge switch group is controlled to cycle-charge the energy storage module using the multiple sub-battery packs. When the absolute value of the difference between the voltage of the first sub-battery pack and the voltage of the energy storage module is less than or equal to the first voltage threshold, the charge / discharge switch group is controlled to connect the multiple sub-battery packs in series and charge the energy storage module. The present invention is characterized by controlling the charge / discharge switch group to cycle-charge the plurality of sub-battery packs using the energy storage module when the voltage of the first sub-battery pack is lower than the voltage of the energy storage module, and the difference between the voltage of the energy storage module and the voltage of the first sub-battery pack is greater than the first voltage threshold, The method according to claim 3.

5. The aforementioned multiple sub-battery packs include two sub-battery packs. By controlling the charge / discharge switch group, the energy storage module is cycle-charged by the multiple sub-battery packs. The first sub-battery pack is designated as a discharge sub-battery pack, and a discharge loss voltage threshold corresponding to the discharge sub-battery pack is determined based on the voltages of the plurality of sub-battery packs. By controlling the charge / discharge switch group to turn on the switch connected to the positive and negative terminals of the discharge sub-battery pack and turn off the other switches, the energy storage module is charged by the discharge sub-battery pack. During the process in which the discharge sub-battery pack charges the energy storage module, the detection module detects the battery temperature of the target battery pack, the temperature rise rate of the target battery pack, and the discharge loss voltage of the discharge sub-battery pack. The method is characterized by the following steps: if it is detected that the battery temperature of the target battery pack is below the second temperature threshold, the temperature rise rate of the target battery pack is equal to or greater than the rate threshold, and the discharge loss voltage of the discharge sub-battery pack is equal to or greater than the discharge loss voltage threshold, then another sub-battery pack is designated as the discharge sub-battery pack, and the process returns to the step of determining the discharge loss voltage threshold corresponding to the discharge sub-battery pack based on the voltages of the plurality of sub-battery packs until the battery temperature of the target battery pack becomes equal to or greater than the second temperature threshold, or the temperature rise rate of the battery pack falls below the rate threshold, The method according to claim 4.

6. During the process in which the discharge sub-battery pack charges the energy storage module, the detection module detects the battery temperature of the target battery pack, the temperature rise rate of the target battery pack, and the discharge loss voltage of the discharge sub-battery pack. After this, the method The further comprising controlling the charge / discharge switch group to connect the plurality of sub-battery packs in series and charge the energy storage module when it is detected that the battery temperature of the target battery pack is below the second temperature threshold and the temperature rise rate of the battery temperature of the target battery pack is below the rate threshold, The method according to claim 5.

7. By controlling the charge / discharge switch group, the multiple sub-battery packs are connected in series to charge the energy storage module. By controlling the switches in the series path of the multiple sub-battery packs to be turned on and the other switches to be turned off, the multiple sub-battery packs are connected in series to charge the energy storage module, In the process of the plurality of sub-battery packs being connected in series to charge the energy storage module, the detection module detects the battery temperature of the target battery pack and the temperature rise rate of the target battery pack. The invention is characterized in that, when it is detected that the battery temperature of the target battery pack is below the second temperature threshold and the rate of temperature rise of the target battery pack is equal to or greater than the rate threshold, the plurality of sub-battery packs are connected in series and continue to charge the energy storage module until the battery temperature of the target battery pack becomes equal to or greater than the second temperature threshold, or until the rate of temperature rise of the battery pack falls below the rate threshold, The method according to claim 4 or 6.

8. In the process of the plurality of sub-battery packs being connected in series to charge the energy storage module, the detection module detects the battery temperature of the target battery pack and the temperature rise rate of the target battery pack, and then the method If it is detected that the battery temperature of the target battery pack is below the second temperature threshold and the rate of temperature rise of the target battery pack is below the rate threshold, the charge / discharge switch group is controlled to cycle-charge the plurality of sub-battery packs by the energy storage module, further comprising: The method according to feature 7.

9. The aforementioned multiple sub-battery packs include two sub-battery packs. By controlling the charge / discharge switch group, the energy storage module cycle-charges the multiple sub-battery packs. From among the aforementioned multiple sub-battery packs, determine the second sub-battery pack with the lowest voltage, The second sub-battery pack is designated as a charging sub-battery pack, and a charging rise voltage threshold corresponding to the charging sub-battery pack is determined based on the voltage of the energy storage module and the voltage of the charging sub-battery pack. The energy storage module charges the sub-battery pack by controlling the switch connected to the positive and negative terminals of the charging sub-battery pack among the charge / discharge switch group to turn on and the other switches to turn off. During the process in which the energy storage module charges the charging sub-battery pack, the detection module detects the battery temperature of the target battery pack, the temperature rise rate of the target battery pack, and the charging voltage rise of the charging sub-battery pack. The process is characterized by the following steps: if it is detected that the battery temperature of the target battery pack is below the second temperature threshold, the temperature rise rate of the target battery pack is equal to or greater than the rate threshold, and the charging voltage of the charging sub-battery pack is equal to or greater than the charging voltage threshold, then another sub-battery pack is designated as the charging sub-battery pack, and the process returns to the step of determining the charging voltage threshold corresponding to the charging sub-battery pack based on the voltage of the energy storage module and the voltage of the charging sub-battery pack until the battery temperature of the target battery pack becomes equal to or greater than the second temperature threshold, or the temperature rise rate of the battery temperature falls below the rate threshold, the process is characterized by the following steps: The method according to claim 4 or 8.

10. During the process in which the energy storage module charges the charging sub-battery pack, the detection module detects the battery temperature of the target battery pack, the temperature rise rate of the target battery pack, and the charging rise voltage of the charging sub-battery pack. After this, the method The further comprising controlling the charge / discharge switch group to cycle-charge the energy storage module using the plurality of sub-battery packs when it is detected that the battery temperature of the target battery pack is below the second temperature threshold and the temperature rise rate of the battery temperature of the target battery pack is below the rate threshold, The method according to claim 9.

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