Battery management method, device and battery management circuit

Abstract

The present application provides a battery management method, device, and battery management circuit, wherein the method includes: the battery management system includes multiple battery management modules, each of which is connected in parallel, wherein each battery management module performs the following steps: determining the chip select signals of multiple other battery management modules connected in parallel with the battery management module; if all are chip select signals indicating slave mode, calculating the time during which the chip select signals of the multiple other battery management modules connected in parallel with the battery management module are all chip select signals indicating slave mode; if the time during which all are chip select signals indicating slave mode exceeds a preset mode hold time of the battery management module, the battery management module enters the master mode. This achieves the effect of autonomously selecting a master slave from multiple battery management modules, ensuring the normal operation of the battery management system.

Description

Technical Field

[0001] The present application relates to the field of battery management technology, and more specifically, to a battery management method, device, and battery management circuit. Background Art

[0002] In recent years, my country has vigorously developed green energy. As an indispensable part of green energy, lithium batteries are closely connected to our lives. The battery management module (BMS) is the brain of the lithium battery system, responsible for managing the operation and safety of the entire battery system.

[0003] Currently, in the existing battery management module (BMS) multi-machine parallel connection technology, once the host in the battery management module (BMS) is determined, it cannot be changed. As a result, the battery management system cannot work normally if the host in the battery management module (BMS) is unplugged or fails, posing a safety hazard. Summary of the Invention

[0004] In view of this, the purpose of the present application is to provide a battery management method, device and battery management circuit, which can autonomously determine the master and slave from multiple battery management modules by judging the chip select signal between multiple battery management modules connected in parallel, and solve the problem in the prior art that the master in the battery management module (BMS) cannot be changed once it is determined, so that the battery management system cannot work normally after the master in the battery management module (BMS) is unplugged or fails, posing a safety hazard. The method achieves the effect of autonomously selecting the master and slave from multiple battery management modules to ensure the normal operation of the battery management system.

[0005] In a first aspect, an embodiment of the present application provides a battery management method, which is applied to a battery management system of an electric vehicle, wherein the battery management system includes multiple battery management modules, each of which is connected in parallel, wherein each battery management module performs the following steps: judging the chip select signals of multiple other battery management modules connected in parallel with the battery management module, the chip select signals being used to indicate whether each battery management module is a chip select signal of a host mode or a chip select signal of a slave mode; if the chip select signals of the multiple other battery management modules connected in parallel with the battery management module are all chip select signals indicating a slave mode, then calculating the time during which the chip select signals of the multiple other battery management modules connected in parallel with the battery management module are all chip select signals indicating a slave mode; if the time during which the chip select signals of the multiple other battery management modules connected in parallel with the battery management module are all chip select signals indicating a slave mode exceeds the mode retention time preset by the battery management module, the battery management module enters the host mode, and the multiple other battery management modules connected in parallel with the battery management module send chip select signals indicating a host mode.

[0006] Optionally, each battery management module has a different preset mode retention time.

[0007] Optionally, the battery management module in host mode also performs the following steps: at preset connection determination time intervals, sending communication requests to other battery management modules in slave mode that are connected in parallel with the battery management module in host mode; for each battery management module in slave mode, determining whether a communication request reply from the battery management module in slave mode has been received; if a communication request reply from the battery management module in slave mode has been received, determining that the battery management module in slave mode is in a working state; if no communication request reply from the battery management module in slave mode has been received, determining that the battery management module in slave mode is not in a working state.

[0008] Optionally, the battery management module in host mode also performs the following steps: at every preset data acquisition time, sending a battery management data acquisition request to each battery management module in working state and in slave mode, and for each battery management module in working state and in slave mode, receiving the battery management data sent by the battery management module in working state and in slave mode.

[0009] Optionally, each battery management module is connected to an external communication device, wherein each battery management module in host mode further performs the following steps: according to a data acquisition request sent by the external communication device, the battery management data of multiple battery management modules are transmitted through the external communication device.

[0010] Optionally, each battery management module added to the battery management system is connected in parallel with other parallel battery management modules, wherein each battery management module added to the battery management system performs the following steps: obtaining the chip select signals of other parallel battery management modules of the battery management system in real time; judging whether the chip select signals of each other parallel battery management module include a chip select signal for indicating that the battery management module is in host mode; if so, the battery management module added to the battery management system enters slave mode; if not, the battery management module added to the battery management system calculates the time when the chip select signals of multiple other battery management modules connected in parallel with the battery management module added to the battery management system are all chip select signals indicating slave mode; if the time when the chip select signals of multiple other battery management modules connected in parallel with the battery management module added to the battery management system are all chip select signals indicating slave mode exceeds the mode retention time preset by the battery management module added to the battery management system, the battery management module added to the battery management system enters host mode, and instructs multiple other battery management modules connected in parallel with the battery management module added to the battery management system to send chip select signals for host mode.

[0011] In a second aspect, an embodiment of the present application further provides a battery management device, which is applied to a battery management system of an electric vehicle. The battery management system includes a plurality of battery management modules, each of which is connected in parallel. The device includes:

[0012] a chip select signal determination module, configured to determine chip select signals of a plurality of other battery management modules connected in parallel with the battery management module, wherein the chip select signal is used to indicate to each battery management module whether it is a chip select signal indicating a master mode or a chip select signal indicating a slave mode;

[0013] a slave mode time calculation module, which calculates the time during which the chip select signals of the multiple other battery management modules connected in parallel with the battery management module are all chip select signals indicating the slave mode if the chip select signals of the multiple other battery management modules connected in parallel with the battery management module are all chip select signals indicating the slave mode;

[0014] A mode determination module, wherein if the chip select signals of multiple other battery management modules connected in parallel with the battery management module are all chip select signals indicating slave mode for a period exceeding the mode retention time preset by the battery management module, the battery management module enters the host mode, and the multiple other battery management modules connected in parallel with the battery management module send the host mode chip select signals.

[0015] On the third aspect, the present application also provides a battery management circuit, which is applied to the battery management system of an electric vehicle. The battery management system includes multiple battery management modules, and the multiple chip select signal pins of each battery management module are respectively connected to the chip select signal pins of other battery management modules to obtain the chip select signals of other battery management modules.

[0016] Optionally, the host output and slave input pins of each battery management module are connected in series, and the battery management module in the host mode transmits data with the battery management module in the slave mode through the host output and slave input pins.

[0017] Optionally, the slave output and host input pins of each battery management module are connected in series, and the battery management module in the slave mode transmits data with the battery management module in the host mode through the slave output and host input pins.

[0018] In a fourth aspect, an embodiment of the present application also provides an electronic device, comprising: a processor, a memory and a bus, wherein the memory stores machine-readable instructions executable by the processor. When the electronic device is running, the processor and the memory communicate through the bus, and when the machine-readable instructions are executed by the processor, the steps of the battery management method as described above are performed.

[0019] In a fifth aspect, an embodiment of the present application further provides a computer-readable storage medium, on which a computer program is stored. When the computer program is run by a processor, the steps of the battery management method as described above are executed.

[0020] A battery management method, device, and battery management circuit provided in the embodiments of the present application can autonomously determine the master and slave from multiple battery management modules by judging the chip select signals between multiple battery management modules connected in parallel. This solves the problem in the prior art that the master in the battery management module (BMS) cannot be changed once it is determined, so that the battery management system cannot work normally after the master in the battery management module (BMS) is unplugged or fails, posing a safety hazard. The method achieves the effect of autonomously selecting the master and slave from multiple battery management modules to ensure the normal operation of the battery management system.

[0021] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, preferred embodiments are given below and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without creative work.

[0023] Figure 1 A flowchart of a battery management method provided in an embodiment of the present application;

[0024] Figure 2 A schematic diagram of a battery management circuit provided in an embodiment of the present application;

[0025] Figure 3 A schematic structural diagram of a battery management device provided in an embodiment of the present application;

[0026] Figure 4 A schematic structural diagram of an electronic device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0027] In order to make the purpose, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all of the embodiments. The components of the embodiments of the present application generally described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the application for which protection is claimed, but merely represents the selected embodiments of the present application. Based on the embodiments of the present application, each other embodiment obtained by those skilled in the art without making creative work falls within the scope of protection of the present application.

[0028] First, the application scenarios to which this application is applicable are introduced. This application can be applied in the field of battery management technology.

[0029] Research has shown that in recent years, my country has vigorously developed green energy. As an indispensable part of green energy, lithium batteries are closely connected to our lives. The battery management module (BMS) is the brain of the lithium battery system, responsible for managing the operation and safety of the entire battery system.

[0030] Currently, in the existing battery management module (BMS) multi-machine parallel connection technology, once the host in the battery management module (BMS) is determined, it cannot be changed. As a result, the battery management system cannot work normally if the host in the battery management module (BMS) is unplugged or fails, posing a safety hazard.

[0031] Based on this, the embodiments of the present application provide a battery management method, device and battery management circuit, which can autonomously determine the master and slave from multiple battery management modules by judging the chip select signal between multiple battery management modules connected in parallel, thereby solving the problem in the prior art that the master in the battery management module (BMS) cannot be changed once it is determined, so that the battery management system cannot work normally after the host in the battery management module (BMS) is unplugged or fails, posing a safety hazard. The method achieves the effect of autonomously selecting the master and slave from multiple battery management modules to ensure the normal operation of the battery management system.

[0032] See also Figure 1 , Figure 1 This is a flow chart of a battery management method provided in an embodiment of the present application. Figure 1 As shown in , the battery management method provided by the embodiment of the present application includes:

[0033] S101 : Determine chip select signals of multiple other battery management modules connected in parallel with the battery management module.

[0034] Wherein, the chip select signal is used to indicate that each battery management module is a chip select signal of a host mode or a chip select signal of a slave mode;

[0035] It should be noted that the battery management system applied to electric vehicles includes a plurality of battery management modules, and each battery management module is connected in parallel.

[0036] See also Figure 2 , Figure 2 This is a schematic diagram of a battery management circuit provided in an embodiment of the present application. Figure 2 As shown in , a schematic diagram of a battery management circuit provided by an embodiment of the present application includes: a battery management module BMS1, a battery management module BMS2, and a battery management module BMS3.

[0037] The multiple chip select signal pins of each battery management module are respectively connected to the chip select signal pins of other battery management modules to obtain the chip select signals of other battery management modules.

[0038] For example, see Figure 2 , Figure 2 The battery management circuit includes: a battery management module BMS1, a battery management module BMS2, and a battery management module BMS3, wherein the chip select signal pin CS1 of the battery management module BMS1 is connected to the chip select signal pin CS2 of the battery management module BMS3; the chip select signal pin CS2 of the battery management module BMS1 is connected to the chip select signal pin CS1 of the battery management module BMS2; and the chip select signal pin CS2 of the battery management module BMS2 is connected to the chip select signal pin CS1 of the battery management module BMS3.

[0039] In this way, the battery management module BMS1 , the battery management module BMS2 , and the battery management module BMS3 can all receive chip select signals from other battery management modules.

[0040] Here, each battery management module has a different preset mode holding time.

[0041] S102: If the chip select signals of the multiple other battery management modules connected in parallel with the battery management module are all chip select signals indicating the slave mode, calculate the time during which the chip select signals of the multiple other battery management modules connected in parallel with the battery management module are all chip select signals indicating the slave mode.

[0042] S103. If the chip select signals of multiple other battery management modules connected in parallel with the battery management module are all chip select signals indicating slave mode for a period of time that exceeds the mode retention time preset by the battery management module, the battery management module enters the host mode and sends the host mode chip select signal to the multiple other battery management modules connected in parallel with the battery management module.

[0043] For example, the preset mode holding time of BMS1 may be 5 seconds, the preset mode holding time of BMS2 may be 10 seconds, and the preset mode holding time of BMS3 may be 15 seconds. When the battery management modules BMS1, BMS2, and BMS3 all have chip select signals indicating slave mode, and when BMS1 detects that the chip select signals of the battery management modules BMS2 and BMS3 are chip select signals indicating slave mode for more than 5 seconds, BMS1 enters the master mode and sends a master mode chip select signal to the battery management modules BMS2 and BMS3.

[0044] Specifically, the battery management module in the host mode also performs the following steps: at every preset connection determination time, sending a communication request to the other battery management modules in the slave mode that are connected in parallel with the battery management module in the host mode; for each battery management module in the slave mode, determining whether a communication request reply from the battery management module in the slave mode has been received; if a communication request reply from the battery management module in the slave mode has been received, determining that the battery management module in the slave mode is in a working state; if no communication request reply from the battery management module in the slave mode has been received, determining that the battery management module in the slave mode is not in a working state.

[0045] Specifically, the master output and slave input pins of each BMS module are connected in series, and the battery management module in master mode transmits data with the battery management module in slave mode through the master output and slave input pins. The slave output and master input pins of each battery management module are connected in series, and the battery management module in slave mode transmits data with the battery management module in master mode through the slave output and master input pins.

[0046] Among them, the battery management module in host mode also performs the following steps: at every preset data acquisition time, a battery management data acquisition request is sent to each battery management module in working state and in slave mode, and for each battery management module in working state and in slave mode, the battery management data sent by the battery management module in working state and in slave mode is received.

[0047] For example, see Figure 2Each BMS module includes a MOSI (master output slave input) pin and a MISO (master input slave output) pin. When BMS1 is in master mode, the MOSI pin of BMS1 can send data acquisition instructions to the MOSI pins of BMS2 and BMS3. After receiving the data acquisition instructions, BMS2 and BMS3 output the battery data collected by BMS2 and BMS3 to the MISO pin of BMS1 through the MISO pins of BMS2 and BMS3.

[0048] Here, the battery data collected by each BMS includes basic battery data such as battery voltage, current, and temperature.

[0049] Optionally, each battery management module is connected to an external communication device.

[0050] Each battery management module in the host mode further performs the following steps: according to a data acquisition request sent by the external communication device, the battery management data of the multiple battery management modules are transmitted through the external communication device.

[0051] Optionally, each battery management module added to the battery management system is connected in parallel with other parallel battery management modules.

[0052] Among them, each battery management module added to the battery management system performs the following steps: obtaining the chip select signals of other parallel battery management modules of the battery management system in real time; judging whether the chip select signals of each other parallel battery management module include a chip select signal for indicating that the battery management module is in host mode; if so, the battery management module added to the battery management system enters slave mode; if not, the battery management module added to the battery management system calculates the time when the chip select signals of multiple other battery management modules connected in parallel with the battery management module added to the battery management system are all chip select signals indicating slave mode; if the time when the chip select signals of multiple other battery management modules connected in parallel with the battery management module added to the battery management system are all chip select signals indicating slave mode exceeds the mode retention time preset by the battery management module added to the battery management system, the battery management module added to the battery management system enters host mode, and the multiple other battery management modules connected in parallel with the battery management module added to the battery management system send chip select signals indicating host mode.

[0053] Optionally, the clock pins of each battery management module are connected in series. Exemplarily, each battery management module can be connected in series and parallel using the SPI bus. The embodiment of the present application provides four-wire communication using the SPI bus, wherein the four-wire communication includes a MOSI (host output slave input) pin, a MISO (host input slave output) pin, an SCLK (clock) pin, and a CS (chip select signal) pin.

[0054] The battery management method provided in the embodiment of the present application can autonomously determine the master and slave from multiple battery management modules by judging the chip select signals between multiple battery management modules connected in parallel, thereby solving the problem in the prior art that the master in the battery management module (BMS) cannot be changed once it is determined, so that the battery management system cannot work normally after the master in the battery management module (BMS) is unplugged or fails, posing a safety hazard. The method achieves the effect of autonomously selecting the master and slave from multiple battery management modules to ensure the normal operation of the battery management system.

[0055] Based on the same inventive concept, a battery management device corresponding to the battery management method is also provided in the embodiment of the present application. Since the principle of solving the problem by the device in the embodiment of the present application is similar to the above-mentioned battery management method in the embodiment of the present application, the implementation of the device can refer to the implementation of the method, and the repeated parts will not be repeated.

[0056] See also Figure 3 , Figure 3 This is a schematic diagram of the structure of a battery management device provided in an embodiment of the present application, which is applied to a battery management system of an electric vehicle. The battery management system includes multiple battery management modules, each of which is connected in parallel. The battery management device 300 includes:

[0057] The chip select signal judgment module 301 judges the chip select signals of multiple other battery management modules connected in parallel with the battery management module, wherein the chip select signals are used to indicate whether each battery management module is a master mode chip select signal or a slave mode chip select signal.

[0058] The slave mode time calculation module 302 calculates the time when the chip select signals of multiple other battery management modules connected in parallel with the battery management module are all chip select signals indicating the slave mode if the chip select signals of multiple other battery management modules connected in parallel with the battery management module are all chip select signals indicating the slave mode.

[0059] The mode determination module 303, if the chip select signals of multiple other battery management modules connected in parallel with the battery management module are all chip select signals indicating slave mode for a time that exceeds the mode retention time preset by the battery management module, the battery management module enters the host mode, and the multiple other battery management modules connected in parallel with the battery management module send the host mode chip select signals.

[0060] The battery management device provided in the embodiment of the present application can autonomously determine the master and slave from multiple battery management modules by judging the chip select signals between multiple battery management modules connected in parallel, thereby solving the problem in the prior art that the master in the battery management module (BMS) cannot be changed once it is determined, so that the battery management system cannot work normally after the master in the battery management module (BMS) is unplugged or fails, posing a safety hazard. The device achieves the effect of autonomously selecting the master and slave from multiple battery management modules to ensure the normal operation of the battery management system.

[0061] See also Figure 4 , Figure 4 This is a schematic diagram of the structure of an electronic device provided in an embodiment of the present application. Figure 4 As shown in FIG, the electronic device 400 includes a processor 410 , a memory 420 and a bus 430 .

[0062] The memory 420 stores machine-readable instructions executable by the processor 410. When the electronic device 400 is running, the processor 410 communicates with the memory 420 via the bus 430. When the machine-readable instructions are executed by the processor 410, the above-mentioned Figure 1 For the steps of the battery management method in the method embodiment shown, the specific implementation method can be found in the method embodiment, which will not be repeated here.

[0063] The embodiment of the present application also provides a computer-readable storage medium on which a computer program is stored. When the computer program is executed by a processor, the computer program can execute the above-mentioned Figure 1 The specific implementation of the steps of the battery management method in the method embodiment shown can be found in the method embodiment, and will not be repeated here.

[0064] Those skilled in the art will clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0065] In the several embodiments provided in this application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. The device embodiments described above are merely schematic. For example, the division of the units is merely a logical function division. There may be other division methods in actual implementation. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed may be through some communication interface, indirect coupling or communication connection of devices or units, which may be electrical, mechanical or other forms.

[0066] The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of these units may be selected to achieve the purpose of this embodiment according to actual needs.

[0067] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0068] If the functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a non-volatile computer-readable storage medium that is executable by a processor. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art, or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes several instructions for enabling a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk.

[0069] Finally, it should be noted that the above-described embodiments are only specific implementation methods of the present application, which are used to illustrate the technical solutions of the present application, rather than to limit them. The scope of protection of the present application is not limited thereto. Although the present application has been described in detail with reference to the above-mentioned embodiments, those skilled in the art should understand that any person skilled in the art can modify or easily conceive of changes to the technical solutions described in the above-mentioned embodiments within the technical scope disclosed in the present application, or perform equivalent replacements for some of the technical features thereof. These modifications, changes, or replacements do not deviate from the spirit and scope of the technical solutions of the embodiments of the present application, and should be included in the scope of protection of the present application. Therefore, the scope of protection of the present application should be based on the scope of protection of the claims.

Claims

1. A battery management method, characterized in that: A battery management system for electric vehicles includes multiple battery management modules, each of which is connected in parallel. Each battery management module performs the following steps: Determining chip select signals of a plurality of other battery management modules connected in parallel with the battery management module, wherein the chip select signals are used to indicate whether each battery management module is a chip select signal of a master mode or a chip select signal of a slave mode; If the chip select signals of the multiple other battery management modules connected in parallel with the battery management module are all chip select signals indicating the slave mode, then calculating the time during which the chip select signals of the multiple other battery management modules connected in parallel with the battery management module are all chip select signals indicating the slave mode; If the chip select signals of multiple other battery management modules connected in parallel with the battery management module are all chip select signals indicating slave mode for a time that exceeds the mode retention time preset by the battery management module, the battery management module enters the host mode and sends chip select signals indicating the host mode to multiple other battery management modules connected in parallel with the battery management module.

2. The method according to claim 1, characterized in that Each battery management module has a different preset mode retention time.

3. The method according to claim 1, characterized in that The battery management module in host mode also performs the following steps: sending communication requests to the other battery management modules in slave mode connected in parallel with the battery management module in master mode at every preset connection confirmation time; For each battery management module in slave mode, determining whether a communication request reply of the battery management module in slave mode has been received; If a communication request reply is received from the battery management module in the slave mode, it is determined that the battery management module in the slave mode is in a working state; If no communication request reply is received from the battery management module in the slave mode, it is determined that the battery management module in the slave mode is not in the working state.

4. The method according to claim 3, characterized in that The battery management module in host mode also performs the following steps: At every preset data acquisition time, a battery management data acquisition request is sent to each battery management module in working state and in slave mode. For each battery management module in the working state and in the slave mode, the battery management data sent by the battery management module in the working state and in the slave mode is received.

5. The method according to claim 1, wherein Each battery management module is connected to an external communication device. Each battery management module in host mode further performs the following steps: According to the data acquisition request sent by the external communication device, the battery management data of the multiple battery management modules are transmitted through the external communication device.

6. The method according to claim 1, characterized in that Each battery management module added to the battery management system is connected in parallel with other parallel battery management modules. Each battery management module added to the battery management system performs the following steps: Real-time acquisition of chip select signals of other parallel battery management modules of the battery management system; determining whether the chip select signal of each other battery management module connected in parallel includes a chip select signal for indicating that the battery management module is in a host mode; If yes, the battery management module added to the battery management system enters slave mode; If not, the battery management module added to the battery management system calculates the time when the chip select signals of multiple other battery management modules connected in parallel with the battery management module added to the battery management system are all chip select signals indicating the slave mode; If the chip select signals of multiple other battery management modules connected in parallel with the battery management module added to the battery management system are all chip select signals indicating slave mode for a time that exceeds the mode retention time preset by the battery management module added to the battery management system, the battery management module added to the battery management system enters the host mode, and the multiple other battery management modules connected in parallel with the battery management module added to the battery management system send chip select signals indicating the host mode.

7. A battery management device, characterized in that: A battery management system for electric vehicles includes a plurality of battery management modules, each of which is connected in parallel. The device includes: a chip select signal determination module, configured to determine chip select signals of a plurality of other battery management modules connected in parallel with the battery management module, wherein the chip select signal is used to indicate to each battery management module whether it is a chip select signal indicating a master mode or a chip select signal indicating a slave mode; a slave mode time calculation module, which calculates the time during which the chip select signals of the multiple other battery management modules connected in parallel with the battery management module are all chip select signals indicating the slave mode if the chip select signals of the multiple other battery management modules connected in parallel with the battery management module are all chip select signals indicating the slave mode; A mode determination module, wherein if the chip select signals of multiple other battery management modules connected in parallel with the battery management module are all chip select signals indicating slave mode for a period exceeding the mode retention time preset by the battery management module, the battery management module enters the host mode, and the multiple other battery management modules connected in parallel with the battery management module send the host mode chip select signals.

8. A battery management circuit, characterized in that: A battery management system for an electric vehicle, the battery management system comprising a plurality of battery management modules, the battery management system for the electric vehicle executing the battery management method according to any one of claims 1 to 6, The multiple chip select signal pins of each battery management module are respectively connected to the chip select signal pins of other battery management modules to obtain the chip select signals of other battery management modules.

9. The battery management circuit according to claim 8, characterized in that: The host output and slave input pins of each battery management module are connected to each other, and the battery management module in the host mode transmits data with the battery management module in the slave mode through the host output and slave input pins.

10. The battery management circuit according to claim 8, characterized in that: The slave output and host input pins of each battery management module are connected, and the battery management module in the slave mode transmits data with the battery management module in the host mode through the slave output and host input pins.

Images