Battery management system and battery management method

Abstract

A battery management system, comprising a low-voltage battery (1), a detection component (2), a controller (3), a memory (4), a charging switch (5), and a discharging switch (6). The controller (3) is separately electrically connected to the detection component (2), the memory (4), the charging switch (5), and the discharging switch (6). The controller (3) is used for: storing received state information in the memory (4); when the state information satisfies a target state condition, determining fault information on the basis of the state information satisfying the state condition; storing the fault information in the memory (4); and, on the basis of the fault information, controlling the charging switch (5) and / or the discharging switch (6). An independent memory is added to the system, which can better assist maintenance personnel in more comprehensively determining a faulty component. Further disclosed is a battery management method.

Description

Battery management system and method of battery management

[0001] The present disclosure claims priority to the Chinese patent application No. 202411114366.1, filed on August 14, 2024, and entitled "Battery management system and method of battery management", the entire content of which is incorporated herein by reference. TECHNICAL FIELD

[0002] The present disclosure relates to the technical field of electric vehicles, in particular to a battery management system and a method of battery management. BACKGROUND

[0003] An electric vehicle includes a low-voltage battery and a high-voltage battery. The low-voltage battery can supply power to low-voltage electrical equipment in the vehicle, and the high-voltage battery can charge the low-voltage battery. When the low-voltage battery fails, the charging and discharging of the low-voltage battery needs to be stopped.

[0004] In related technologies, a controller monitors related parameters of the low-voltage battery in real time, analyzes fault information of the low-voltage battery, stores the fault information in a cache of the controller, and controls a charging and discharging switch of the low-voltage battery according to the stored current fault information, while sending a prompt signal (such as a fault light) to the user. After a fault occurs, the user can send the vehicle to a repair shop, and the repair personnel can determine the faulty components based on the fault information in the cache and their own experience, and then perform maintenance.

[0005] The cache space of the controller is very small, so when new fault information needs to be stored, the new fault information will overwrite the old fault information. However, it is difficult to accurately locate all the faulty components based on only the latest fault information. For example, multiple faults have occurred before the vehicle is sent for repair, and different components have failed. Currently, only the latest fault component can be located. SUMMARY

[0006] The present disclosure provides a battery management system and a method of battery management, which can solve the above technical problems in related technologies. The technical solution is as follows:

[0007] In a first aspect, a battery management system is provided, which includes a low-voltage battery, a detection component, a controller, a memory, a charging switch, and a discharging switch.

[0008] The detection component is electrically connected to the low-voltage battery and the controller, and is configured to detect state information of the low-voltage battery, wherein the state information includes current, voltage, and battery temperature, and send the state information to the controller.

[0009] The charging switch is configured to control the connection and disconnection of the low-voltage battery and the high-voltage battery.

[0010] The discharge switch is used for on-off control of electrical connection of the low-voltage battery and the low-voltage load.

[0011] The controller is electrically connected with the detection component, the memory, the charge switch and the discharge switch respectively, and is configured to: store the received state information in the memory, determine fault information based on the state information meeting the target state condition when the state information meets the target state condition, store the fault information in the memory, and control the charge switch and / or the discharge switch based on the fault information.

[0012] In a possible implementation, the controller comprises a control chip and a drive chip.

[0013] The control chip is electrically connected with the drive chip and the detection component respectively, and is configured to: store the received state information in the memory, determine fault information based on the state information meeting the target state condition when the state information meets the target state condition, store the fault information in the memory, determine a control instruction based on the fault information, and send the control instruction to the drive chip.

[0014] The drive chip is electrically connected with the charge switch and the discharge switch respectively, and is configured to control the charge switch and / or the discharge switch based on the control instruction.

[0015] In a possible implementation, the controller is configured to:

[0016] When a target state condition exists in a first correspondence relationship between the pre-stored state conditions, state information ranges and fault levels, and the current received state information meets the target state condition, in the first correspondence relationship, a target fault level corresponding to the target state condition and a target state information range to which the current received state information belongs is determined.

[0017] A target fault type corresponding to the target state condition is determined based on a second correspondence relationship between the pre-stored state conditions and fault types.

[0018] The target fault type and the target fault level are determined as the fault information.

[0019] In a possible implementation, the controller is configured to:

[0020] When the target state condition is that the discharge current is greater than a first discharge current threshold, it is determined that a corresponding target fault type is a short-circuit fault.

[0021] when the target state condition is that the total voltage of the battery is less than a total voltage threshold, determining that a corresponding target fault type is an under-voltage fault;

[0022] when the target state condition is that the cell voltage is greater than a cell voltage threshold, determining that a corresponding target fault type is an over-voltage fault;

[0023] when the target state condition is that the charging current is greater than a charging current threshold, determining that a corresponding target fault type is a charging over-current fault;

[0024] when the target state condition is that the discharging current is greater than a second discharging current threshold, determining that a corresponding target fault type is a discharging over-current fault;

[0025] when the target state condition is that the cell temperature is greater than a cell temperature threshold, determining that a corresponding target fault type is an over-temperature fault;

[0026] when the target state condition is that the cell temperature is greater than a cell temperature threshold and a temperature increase speed is greater than a temperature increase speed threshold for a target time length, determining that a corresponding target fault type is a thermal runaway fault.

[0027] In a possible implementation manner, the controller is configured to:

[0028] when a target state condition exists in a first correspondence relationship between a pre-stored state condition, a state information range, a fault level and a detection time length, and current received state information satisfies the target state condition, in the first correspondence relationship, determining a target fault level and a target detection time length corresponding to the target state condition and a target state information range to which the current received state information belongs, wherein in the first correspondence relationship, the fault level and the target detection time length are negatively correlated;

[0029] if the state information received within the target detection time length all satisfy the target state condition, determining a target fault type corresponding to the target state condition based on a second correspondence relationship between a pre-stored state condition and a fault type.

[0030] In a possible implementation manner, the controller is configured to:

[0031] determining a target control instruction corresponding to the target fault type based on a third correspondence relationship between a fault type and a control instruction, and controlling the charging switch and / or the discharging switch based on the target control instruction.

[0032] In a possible implementation manner,

[0033] the fault types include an under-voltage fault, a short-circuit fault, an over-voltage fault, a charging over-current fault, a discharging over-current fault, an over-temperature fault and a thermal runaway fault.

[0034] The controller is configured to:

[0035] when the target fault type is an under-voltage fault, determining that the target control instruction is to open the discharge switch;

[0036] when the target fault type is a short-circuit fault, determining that the target control instruction is to open the charging switch and the discharge switch;

[0037] when the target fault type is an over-voltage fault, determining that the target control instruction is to open the charging switch;

[0038] when the target fault type is a charging over-current fault, determining that the target control instruction is to open the charging switch;

[0039] when the target fault type is a discharging over-current fault, determining that the target control instruction is to open the discharge switch;

[0040] when the target fault type is an over-temperature fault or a thermal runaway fault, determining that the target control instruction is to open the charging switch and the discharge switch.

[0041] In one possible implementation, the controller is configured to:

[0042] when the target fault type is an over-temperature fault or a thermal runaway fault, if both the charging switch and the discharge switch are in a connected state, determining a current value of the high-voltage battery and the low-voltage battery connection line and a current value of the low-voltage load and the low-voltage battery connection line, when the current value of the high-voltage battery and the low-voltage battery connection line is greater than a first current threshold, determining that the target control instruction includes opening the charging switch, when the current value of the low-voltage load and the low-voltage battery connection line is greater than a second current threshold, determining that the target control instruction includes opening the discharge switch, if one of the charging switch and the discharge switch is in a connected state, determining that the target control instruction is to open the one switch.

[0043] In one possible implementation, the controller is configured to:

[0044] When the target fault type is an over-temperature fault or a thermal runaway fault, if both the charging switch and the discharging switch are in the connected state, the target control instruction is determined to be to disconnect the discharging switch, after the target control instruction is executed, if it is detected that the received state information does not satisfy the target state condition, the switch state is kept unchanged, if it is detected again that the received state information satisfies the target state condition, the target control instruction is determined again to be to connect the discharging switch and disconnect the charging switch, after the target control instruction is executed, if it is detected that the received state information does not satisfy the target state condition, the switch state is kept unchanged, if it is detected again that the received state information satisfies the target state condition, the target control instruction is determined again to be to disconnect the charging switch and the discharging switch, if one of the charging switch and the discharging switch is in the connected state, the target control instruction is determined to be to disconnect the one switch.

[0045] In a possible implementation, the battery management system further comprises a communication component and a fault light;

[0046] The communication component is electrically connected with the controller and the fault light respectively.

[0047] The controller is further configured to: when the state information satisfies a target state condition, send a target indication signal to the fault light through the communication component, so that the fault light emits a light signal based on the target indication signal.

[0048] In a second aspect, a battery management method is provided, which is applied to a battery management system, the battery management system comprising a low-voltage battery, a detection component, a controller, a memory, a charging switch and a discharging switch, and the method comprising:

[0049] The detection component detects state information of the low-voltage battery, wherein the state information comprises current, voltage and battery cell temperature, and sends the state information to the controller;

[0050] The controller stores the received state information in the memory, when the state information satisfies a target state condition, determines fault information based on the state information satisfying the state condition, stores the fault information in the memory, and controls the charging switch and / or the discharging switch based on the fault information.

[0051] In a possible implementation, when the state information satisfies a target state condition, determining fault information based on the state information satisfying the state condition comprises:

[0052] When the target state condition exists in the first correspondence relationship between the pre-stored state conditions, the state information range and the fault level, and the current received state information satisfies the target state condition, in the first correspondence relationship, a target fault level corresponding to the target state condition and a target state information range to which the current received state information belongs is determined;

[0053] A target fault type corresponding to the target state condition is determined based on a second correspondence relationship between the pre-stored state conditions and the fault types.

[0054] The target fault type and the target fault level are determined as the fault information.

[0055] In a possible implementation manner, the target fault type corresponding to the target state condition is determined based on the second correspondence relationship between the pre-stored state conditions and the fault types, and includes:

[0056] When the target state condition is that the discharge current is greater than a first discharge current threshold, it is determined that the corresponding target fault type is a short circuit fault.

[0057] When the target state condition is that the total voltage of the battery is less than a total voltage threshold, it is determined that the corresponding target fault type is an under-voltage fault.

[0058] When the target state condition is that the cell voltage is greater than a cell voltage threshold, it is determined that the corresponding target fault type is an over-voltage fault.

[0059] When the target state condition is that the charging current is greater than a charging current threshold, it is determined that the corresponding target fault type is a charging over-current fault.

[0060] When the target state condition is that the discharge current is greater than a second discharge current threshold, it is determined that the corresponding target fault type is a discharge over-current fault.

[0061] When the target state condition is that the cell temperature is greater than a cell temperature threshold, it is determined that the corresponding target fault type is an over-temperature fault.

[0062] When the target state condition is that the cell temperature is greater than a cell temperature threshold and a temperature increase speed is greater than a temperature increase speed threshold for a target time length, it is determined that the corresponding target fault type is a thermal runaway fault.

[0063] In a possible implementation manner, when the target state condition exists in the first correspondence relationship between the pre-stored state conditions, the state information range and the fault level, and the current received state information satisfies the target state condition, in the first correspondence relationship, the target fault level corresponding to the target state condition and the target state information range to which the current received state information belongs is determined, and includes:

[0064] When the target state condition exists in the first correspondence relationship between the pre-stored state condition, the state information range, the fault level and the detection duration, and the current received state information satisfies the target state condition, in the first correspondence relationship, a target fault level and a target detection duration corresponding to the target state condition and a target state information range to which the current received state information belongs are determined, wherein the fault level and the target detection duration are negatively correlated in the first correspondence relationship;

[0065] The second correspondence relationship between the pre-stored state condition and the fault type is used to determine a target fault type corresponding to the target state condition, and includes:

[0066] If the state information received within the target detection duration all satisfy the target state condition, the second correspondence relationship between the pre-stored state condition and the fault type is used to determine a target fault type corresponding to the target state condition.

[0067] In a possible implementation manner, the control of the charging switch and / or the discharging switch based on the fault information includes:

[0068] A third correspondence relationship between a fault type and a control instruction is used to determine a target control instruction corresponding to the target fault type, and the charging switch and / or the discharging switch are controlled based on the target control instruction.

[0069] In a possible implementation manner, the fault type includes an under-voltage fault, a short-circuit fault, an over-voltage fault, a charging over-current fault, a discharging over-current fault, an over-temperature fault and a thermal runaway fault.

[0070] The third correspondence relationship between the fault type and the control instruction is used to determine the target control instruction corresponding to the target fault type, and includes:

[0071] When the target fault type is the under-voltage fault, it is determined that the target control instruction is to disconnect the discharging switch.

[0072] When the target fault type is the short-circuit fault, it is determined that the target control instruction is to disconnect the charging switch and the discharging switch.

[0073] When the target fault type is the over-voltage fault, it is determined that the target control instruction is to disconnect the charging switch.

[0074] When the target fault type is the charging over-current fault, it is determined that the target control instruction is to disconnect the charging switch.

[0075] When the target fault type is the discharging over-current fault, it is determined that the target control instruction is to disconnect the discharging switch.

[0076] When the target fault type is an over-temperature fault or a thermal runaway fault, it is determined that the target control instruction is to turn off the charging switch and the discharging switch.

[0077] In one possible implementation, the battery management system further includes a communication component and a fault light, and the method further includes:

[0078] When the state information satisfies a target state condition, the controller sends a target indication signal to the fault light through the communication component, so that the fault light emits a light signal based on the target indication signal.

[0079] In the present disclosure, an independent memory is added, and the storage space of the independent memory can be much larger than the cache of the controller itself. In this way, the memory can store the fault information corresponding to multiple faults of the low-voltage battery in a period of time and the state information of the low-voltage battery in the period of time. During the fault maintenance process, these information can better assist the maintenance personnel to comprehensively determine the faulty components. BRIEF DESCRIPTION OF DRAWINGS

[0080] In order to more clearly illustrate the technical solutions in the embodiments of the present disclosure, the drawings needed in the embodiment description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present disclosure, and other drawings can be obtained by those skilled in the art without creative labor.

[0081] FIG. 1 is a position schematic diagram of a battery management system according to an embodiment of the present disclosure;

[0082] FIG. 2 is a structural schematic diagram of a battery management system according to an embodiment of the present disclosure;

[0083] FIG. 3 is a structural schematic diagram of a controller according to an embodiment of the present disclosure;

[0084] FIG. 4 is a structural schematic diagram of a control chip according to an embodiment of the present disclosure;

[0085] FIG. 5 is a structural schematic diagram of a battery management system according to an embodiment of the present disclosure;

[0086] FIG. 6 is a processing flow schematic diagram of determining a control instruction according to an embodiment of the present disclosure;

[0087] FIG. 7 is a structural schematic diagram of a battery management system according to an embodiment of the present disclosure.

[0088] Reference signs: 1, low-voltage battery; 2, detection component; 3, controller, 31, control chip, 32, drive chip, 33, anti-interference chip; 4, memory; 5, charging switch; 6, discharging switch; 7, communication component; 8, fault lamp. DETAILED DESCRIPTION

[0089] In order to make the purpose, technical solutions and advantages of the present disclosure clearer, the embodiments of the present disclosure will be further described in detail below with reference to the drawings.

[0090] An electric vehicle includes a low-voltage battery and a high-voltage battery. The low-voltage battery can supply power to low-voltage electrical equipment in the vehicle, and the high-voltage battery can charge the low-voltage battery. When the low-voltage battery fails, the charging and discharging of the low-voltage battery needs to be stopped. In the related art, the controller monitors the relevant parameters of the low-voltage battery in real time, analyzes the fault information of the low-voltage battery, stores it in the cache of the controller, and controls the charging and discharging switch of the low-voltage battery according to the stored current fault information. After the failure occurs, the maintenance personnel will determine the faulty component based on the fault information in the cache and their own experience, and then carry out maintenance. The cache space of the controller is very small, so when new fault information needs to be stored, the old fault information will be overwritten by the new fault information. However, it is difficult to accurately locate all the faulty components based on only the latest fault information. For example, multiple failures have occurred before the vehicle is sent for repair, and different components have failed. Currently, only the latest faulty component can be located.

[0091] To solve the above problems, the present disclosure provides a battery management system, which is applied to a vehicle, for example, as shown in FIG. 1, the battery management system comprises a low-voltage battery 1, a detection component 2, a controller 3 (not shown in FIG. 1), a memory 4 (not shown in FIG. 1), a charging switch 5 (not shown in FIG. 1) and a discharging switch 6 (not shown in FIG. 1), the low-voltage battery 1 is located in the engine compartment of the vehicle, the detection component 2, the controller 3, the memory 4, the charging switch 5 and the discharging switch 6 are respectively installed near the low-voltage battery 1, the position distribution of the battery management system on the vehicle can be shown in FIG. 1, the positions of the controller 3, the memory 4, the charging switch 5 and the discharging switch 6 are close to the position of the detection component 2 in FIG. 1. The detection component 2 is electrically connected with the low-voltage battery 1 and the controller 3 respectively, and is used to detect state information of the low-voltage battery 1, wherein the state information includes current, voltage and cell temperature, and is sent to the controller 3. The detection component 2 can detect the state information of the low-voltage battery 1 in real time, or can detect the state information of the low-voltage battery 1 periodically, and the detection period can be set by a technician in advance, for example, 10 milliseconds, etc. The detection component 2 can report a current sensor, a voltage sensor, a temperature sensor, etc., the current sensor can detect the discharge current and the charging current, the voltage sensor can detect the total voltage of the battery and the cell voltage, and the temperature sensor can detect the cell temperature. The charging switch 5 is used to control the on-off of the electrical connection between the low-voltage battery 1 and a high-voltage battery, the high-voltage battery is electrically connected with the low-voltage battery 1, and when the remaining power ratio of the low-voltage battery 1 is lower than a threshold value, the high-voltage battery can charge the low-voltage battery 1. The discharging switch 6 is used to control the on-off of the electrical connection between the low-voltage battery 1 and a low-voltage load. The vehicle has a plurality of low-voltage loads, for example, a loudspeaker, an instrument display, etc., and the low-voltage battery 1 is electrically connected with the plurality of low-voltage loads respectively, and when the user starts the low-voltage load, the low-voltage battery 1 can supply power to the low-voltage load. The controller 3 is electrically connected with the detection component 2, the memory 4, the charging switch 5 and the discharging switch 6 respectively, for example, as shown in FIG. 2. The controller 3 is used to store the received state information into the memory 4, when the state information meets a target state condition, based on the state information meeting the state condition, to determine fault information, to store the fault information into the memory 4, and to control the charging switch 5 and / or the discharging switch 6 based on the fault information.

[0092] In a possible implementation, as shown in FIG.3, the controller 3 includes a control chip 31 and a drive chip 32. The control chip 31 is electrically connected with the drive chip 32, the detection component 2 and the memory 4 respectively. The control chip 31 is configured to store the received state information in the memory 4, determine fault information based on the state information satisfying the target state condition when the state information satisfies the target state condition, store the fault information in the memory 4, determine a control instruction based on the fault information, and send the control instruction to the drive chip 32. The drive chip 32 is electrically connected with the charging switch 5 and the discharging switch 6 respectively. The drive chip 32 is configured to control the charging switch 5 and / or the discharging switch 6 based on the control instruction.

[0093] The control chip 31 can perform various calculations, receive and store collected data, and the like.

[0094] The control chip 31 can include a processor 311 and a memory 312, as shown in FIG.4.

[0095] The processor 311 can be a central processing unit (CPU) or a system on chip (SoC), and the like. The processor 311 can be configured to process various operation instructions, for example, determine whether the received state information satisfies the state condition, and the like.

[0096] The memory 312 can include various volatile memories or non-volatile memories, such as a solid state disk (SSD), a dynamic random access memory (DRAM), and the like. The memory 312 can be configured to store initial data, intermediate data and result data used in related processing processes, for example, a first correspondence relationship between the state condition, the range of state information and the fault level, and the like.

[0097] In addition, the control chip 31 can further include a communication module configured to communicate with other devices or components.

[0098] In a possible implementation, the control instruction can be interfered by a signal during transmission, and the controller 3 can further include a deinterference chip 33, as shown in FIG.5, which is electrically connected to the control chip 31 and the driving chip 32 respectively. The deinterference chip 33 can process the control instruction sent by the control chip 31, remove other interference signals in the signal sent by the control chip 31 except the control instruction, and send the control instruction after removing the interference to the driving chip 32. Alternatively, the deinterference chip 33 can have two, one as a main deinterference chip and the other as a backup deinterference chip, and the control chip 31 sends the control instruction to the two deinterference chips 33 at the same time. After receiving the control instruction, the two deinterference chips 33 process the control instruction and send the control instruction after removing the interference to the driving chip 32. In this way, the deinterference chip 33 can remove the interference signal in the environment and improve the signal quality of the control instruction.

[0099] In a possible implementation, the controller 3 determines the processing flow of the control instruction, as shown in FIG.6, including the following steps.

[0100] 601. When the target state condition exists in the first correspondence between the pre-stored state condition, the state information range and the fault level, and the current received state information satisfies the target state condition, the controller 3 determines, in the first correspondence, a target fault level corresponding to the target state condition and a target state information range to which the current received state information belongs.

[0101] The same state condition includes different fault levels, and different state information ranges in the same state condition correspond to different fault levels. The first correspondence between the state condition, the state information range, the fault level and the detection duration can be shown in Table 1, for example.

[0102] Table 1

[0103] After receiving the state information, the controller 3 compares the state information with the state condition one by one. When the target state condition exists in the first correspondence between the pre-stored state condition, the state information range, the fault level and the detection duration, and the current received state information satisfies the target state condition, the controller 3 determines, in the first correspondence, a target fault level and a target detection duration corresponding to the target state condition and a target state information range to which the current received state information belongs, wherein the fault level and the target detection duration are negatively correlated in the first correspondence. For example, the charging current in the current received state information of the controller 3 is 215 A, the target state condition satisfied is "charging current greater than 200 A", and it is further determined in the first correspondence that the target state information range is "(210, 220]". Then, the corresponding target fault level is the second level, and the target detection duration is 15 seconds.

[0104] 602, the controller 3 determines a target fault type corresponding to the target state condition based on a second correspondence relationship between state conditions and fault types pre-stored.

[0105] If the state information received within the target detection duration all meet the target state condition, the target fault type corresponding to the target state condition is determined based on the second correspondence relationship between state conditions and fault types pre-stored.

[0106] When the target state condition is that the discharge current is greater than a first discharge current threshold, the corresponding target fault type is determined to be a short circuit fault; when the target state condition is that the total voltage of the battery is less than a total voltage threshold, the corresponding target fault type is determined to be an under-voltage fault; when the target state condition is that the cell voltage is greater than a cell voltage threshold, the corresponding target fault type is determined to be an over-voltage fault; when the target state condition is that the charging current is greater than a charging current threshold, the corresponding target fault type is determined to be a charging over-current fault; when the target state condition is that the discharge current is greater than a second discharge current threshold, the corresponding target fault type is determined to be a discharge over-current fault, wherein the second discharge current threshold is less than the first discharge current threshold; when the target state condition is that the cell temperature is greater than a cell temperature threshold, the corresponding target fault type is determined to be an over-temperature fault; when the target state condition is that the cell temperature is greater than a cell temperature threshold and the temperature increase speed continues to be greater than a temperature increase speed threshold within a target duration, the corresponding target fault type is determined to be a thermal runaway fault. The second correspondence relationship between state conditions and fault types can be shown in Table 2, and different state conditions correspond to different fault types.

[0107] Table 2

[0108] If, within the first detection duration (target detection duration), there is a second detection duration, in the first correspondence relationship, the second detection duration and the target state condition correspond to a second fault level and a second state information range, and the state information received within the second detection duration all meet the second state information range, the first fault type and the second fault level are determined as the fault information at the end of the second detection duration, the fault information is stored in the memory 4, and the charging switch 5 and / or the discharging switch 6 are controlled based on the fault information. The second detection duration is less than the first detection duration (target detection duration).

[0109] 603, the controller 3 determines the target fault type and the target fault level as the fault information.

[0110] The controller 3 sends the fault information to the memory 4 for storage.

[0111] 604, the controller 3 determines a target control instruction corresponding to the target fault type based on a third correspondence relationship between fault types and control instructions, and controls the charging switch 5 and / or the discharging switch 6 based on the target control instruction.

[0112] The third correspondence relationship between fault types and control instructions can be as shown in Table 3.

[0113] Table 3

[0114] The fault types include an under-voltage fault, a short-circuit fault, an over-voltage fault, a charging over-current fault, a discharging over-current fault, an over-temperature fault, and a thermal runaway fault. When the target fault type is the under-voltage fault, the target control instruction is determined to be to turn off the discharging switch 6. When the target fault type is the short-circuit fault, the target control instruction is determined to be to turn off the charging switch 5 and the discharging switch 6. When the target fault type is the over-voltage fault, the target control instruction is determined to be to turn off the charging switch 5. When the target fault type is the charging over-current fault, the target control instruction is determined to be to turn off the charging switch 5. When the target fault type is the discharging over-current fault, the target control instruction is determined to be to turn off the discharging switch 6.

[0115] When the target fault type is the over-temperature fault or the thermal runaway fault, there can be multiple control logics, which are exemplarily described as follows:

[0116] Control logic one:

[0117] When the target fault type is the over-temperature fault or the thermal runaway fault, the target control instruction is determined to be to turn off the discharging switch 6 and the charging switch 5.

[0118] Control logic two:

[0119] When the target fault type is the over-temperature fault or the thermal runaway fault, a target working condition of the low-voltage battery 1 and a target control instruction corresponding to the target fault type are determined based on a fourth correspondence relationship between working conditions of the low-voltage battery 1, fault types, and control instructions. The fourth correspondence relationship can be as shown in Table 4.

[0120] Table 4

[0121] When the target fault type is an over-temperature fault or a thermal runaway fault, if the charging switch 5 and the discharging switch 6 are both in the connected state, the current value of the high-voltage battery and the low-voltage battery 1 connection line and the current value of the low-voltage load and the low-voltage battery 1 connection line are determined, when the current value of the high-voltage battery and the low-voltage battery 1 connection line is greater than the first current threshold value, it is determined that the target control instruction includes disconnecting the charging switch 5, when the current value of the low-voltage load and the low-voltage battery 1 connection line is greater than the second current threshold value, it is determined that the target control instruction includes disconnecting the discharging switch 6; if one of the charging switch 5 and the discharging switch 6 is in the connected state, it is determined that the target control instruction is to disconnect the one of the charging switch 5 and the discharging switch 6 in the connected state.

[0122] Alternatively, when the target fault type is an over-temperature fault or a thermal runaway fault, if the charging switch 5 and the discharging switch 6 are both in the connected state, it is determined that the target control instruction is to disconnect the discharging switch 6, after executing the target control instruction, if it is not detected that the received state information satisfies the target state condition, the switch state is kept unchanged, if the received state information is detected again to satisfy the target state condition, the target control instruction is re-determined to be connected to the discharging switch 6 and disconnected to the charging switch 5, after executing the target control instruction, if it is not detected that the received state information satisfies the target state condition, the switch state is kept unchanged, if the received state information is detected again to satisfy the target state condition, the target control instruction is re-determined to be disconnected to the charging switch 5 and the discharging switch 6, if one of the charging switch 5 and the discharging switch 6 is in the connected state, it is determined that the target control instruction is to disconnect the one of the charging switch 5 and the discharging switch 6 in the connected state.

[0123] Different fault types correspond to different fault components. The fault components corresponding to the under-voltage fault, over-voltage fault, and discharge over-current fault are the controller. The fault component corresponding to the short-circuit fault is the low-voltage battery (the distance between the positive and negative poles of the low-voltage battery connected to the electrical equipment is too small). The fault components corresponding to the charging over-current fault, over-temperature fault, and thermal runaway fault are the low-voltage battery. The controller 3 can send the state information and fault information stored in the memory 4 within a specified historical time period to the target device. The specified historical time period can be set before the car is shipped. The target device displays the state information and fault information within the specified historical time period. The maintenance personnel can determine the fault component based on the state information and fault information. The target device obtains the input fault component. Alternatively, the fault component can also be determined by a machine learning model. The state information and fault information within the specified historical time period are input into the fault component determination model to obtain the fault component output by the fault component determination model. The fault component determination model can be a decision tree model, a convolutional neural network, etc. For example, the fault type is the thermal runaway fault. The maintenance personnel can determine that the corresponding fault component is the low-voltage battery by checking the table. Based on the sampled battery cell temperatures of the multiple low-voltage batteries in the state information, the position of the low-voltage battery with the highest battery cell temperature can be further determined as the fault position.

[0124] In one possible implementation, the battery management system further includes a communication component 7 and a fault lamp 8, as shown in FIG. 7. The communication component 7 is electrically connected to the control chip 31 and the fault lamp 8, respectively. The fault lamp 8 can be installed on the instrument panel. When the state information meets the target state condition, the controller 3 sends a target indication signal to the fault lamp 8 through the communication component 7, so that the fault lamp 8 emits a light signal based on the target indication signal.

[0125] In the embodiments of the present disclosure, an independent memory is added. The storage space of the independent memory can be much larger than the cache of the controller. Thus, the memory can store the fault information corresponding to the multiple faults of the low-voltage battery within a period of time and the state information of the low-voltage battery within the period of time. During the fault maintenance process, these information can better assist the maintenance personnel to comprehensively determine the fault components.

[0126] In the description of the specification, the description of the terms "certain embodiments", "one embodiment", "some embodiments", "illustrative embodiments", "example", "specific example" or "some examples" means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present disclosure. In the specification, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any appropriate manner in one or more embodiments or examples. In addition, the person skilled in the art can combine and combine the different embodiments or examples described in the specification and the features of the different embodiments or examples without contradiction.

[0127] It can be understood that "multiple" in the present disclosure means two or more, and other quantifiers are similar. The association relationship of the associated objects described by "and / or" means that there can be three relationships, for example, A and / or B can mean that A exists alone, A and B exist together, and B exists alone. The character " / " generally represents that the associated objects before and after are in an "or" relationship. The singular form of "a", "said" and "the" is also intended to include the plural form, unless the context clearly indicates otherwise.

[0128] It can be further understood that the terms "first", "second", etc. are used to describe various information, but these information should not be limited to these terms. These terms are only used to distinguish the same type of information from each other, and do not represent a specific order or importance. In fact, the expressions of "first", "second", etc. can be used interchangeably. For example, the first information can also be referred to as the second information, and similarly, the second information can also be referred to as the first information without departing from the scope of the present disclosure.

[0129] It can be further understood that the terms "center", "longitudinal", "transverse", "front", "back", "up", "down", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the embodiments and simplifying the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation.

[0130] It will be further understood that terms, such as "mounting", "connecting", "connecting", "fixing", etc., are to be interpreted broadly in accordance with their usage in the relevant art, and that not all embodiments according to the disclosure necessarily include the same features or steps. Therefore, the above description and illustrations should not be construed as limiting the scope of the disclosure, which is defined in the appended claims.

[0131] It will be further understood that the operations described in the embodiments of the disclosure are not necessarily performed in the order described, and that other operations can be performed, or described operations can be performed in a different order, or omitted, depending on the specific context. Multiple tasks and operations can be performed at the same time, and / or omitted, depending on the specific context.

[0132] Other embodiments of the disclosure will be apparent to those skilled in the art from consideration of the specification and practice of the concepts disclosed herein. It is intended that the specification and examples be considered as exemplary only, with the true scope and spirit of the disclosure being indicated by the following claims.

[0133] It will be understood that the disclosure is not limited to the precise structures herein described and illustrated in the drawings, and that various modifications and changes can be made without departing from the scope thereof. The scope of the disclosure is limited only by the claims that follow.

Claims

1. A battery management system, characterized by, The battery management system comprises a low-voltage battery (1), a detection component (2), a controller (3), a memory (4), a charging switch (5) and a discharging switch (6); The detection component (2) is electrically connected with the low-voltage battery (1) and the controller (3) respectively, and is used for detecting state information of the low-voltage battery (1), wherein the state information comprises current, voltage and battery temperature, and is sent to the controller (3); The charging switch (5) is used for controlling the on-off of the electrical connection between the low-voltage battery (1) and a high-voltage battery; The discharging switch (6) is used for controlling the on-off of the electrical connection between the low-voltage battery (1) and a low-voltage load; The controller (3) is electrically connected with the detection component (2), the memory (4), the charging switch (5) and the discharging switch (6) respectively, and is used for storing the received state information into the memory (4), determining fault information based on the state information meeting the target state condition when the state information meets the target state condition, storing the fault information into the memory (4), and controlling the charging switch (5) and / or the discharging switch (6) based on the fault information.

2. The battery management system of claim 1, wherein, The controller (3) comprises a control chip (31) and a driving chip (32); The control chip (31) is electrically connected with the driving chip (32) and the detection component (2) respectively, and is used for storing the received state information into the memory (4), determining fault information based on the state information meeting the target state condition when the state information meets the target state condition, storing the fault information into the memory (4), determining a control instruction based on the fault information, and sending the control instruction to the driving chip (32); The driving chip (32) is electrically connected with the charging switch (5) and the discharging switch (6) respectively, and is used for controlling the charging switch (5) and / or the discharging switch (6) based on the control instruction.

3. The battery management system of claim 1, wherein, The controller (3) is used for: When a target state condition exists in a first correspondence relationship between a state condition, a state information range and a fault level, and current received state information meets the target state condition, in the first correspondence relationship, a target fault level corresponding to the target state condition and a target state information range to which the current received state information belongs is determined; A target fault type corresponding to the target state condition is determined based on a second correspondence relationship between a state condition and a fault type which is stored in advance; The target fault type and the target fault level are determined as fault information.

4. The battery management system of claim 3, wherein, The controller (3) is used for: When the target state condition is that a discharging current is greater than a first discharging current threshold, a corresponding target fault type is determined to be a short circuit fault; When the target state condition is that a total battery voltage is less than a total voltage threshold, a corresponding target fault type is determined to be an under-voltage fault; when the target state condition is that the battery cell voltage is greater than a battery cell voltage threshold, determining that the corresponding target fault type is an overvoltage fault; when the target state condition is that the charging current is greater than a charging current threshold, determining that the corresponding target fault type is a charging overcurrent fault; when the target state condition is that the discharging current is greater than a second discharging current threshold, determining that the corresponding target fault type is a discharging overcurrent fault, wherein the second discharging current threshold is less than the first discharging current threshold; when the target state condition is that the battery cell temperature is greater than a battery cell temperature threshold, determining that the corresponding target fault type is an overtemperature fault; when the target state condition is that the battery cell temperature is greater than a battery cell temperature threshold and the temperature increase speed is greater than a temperature increase speed threshold for a target time length, determining that the corresponding target fault type is a thermal runaway fault.

5. The battery management system of claim 3, wherein, The controller (3) is configured to: when a target state condition exists in a first correspondence relationship between a pre-stored state condition, a state information range, a fault level, and a detection time length, and current received state information satisfies the target state condition, determining, in the first correspondence relationship, a target fault level and a target detection time length corresponding to the target state condition and a target state information range to which the current received state information belongs, wherein, in the first correspondence relationship, the fault level and the target detection time length are negatively correlated; if the state information received within the target detection time length all satisfy the target state condition, determining a target fault type corresponding to the target state condition based on a second correspondence relationship between a pre-stored state condition and a fault type.

6. The battery management system of claim 3, wherein, The controller (3) is configured to: determining a target control instruction corresponding to the target fault type based on a third correspondence relationship between a fault type and a control instruction, and controlling the charging switch (5) and / or the discharging switch (6) based on the target control instruction.

7. The battery management system of claim 6, wherein, The fault type includes an under-voltage fault, a short-circuit fault, an over-voltage fault, a charging overcurrent fault, a discharging overcurrent fault, an overtemperature fault, and a thermal runaway fault; The controller (3) is configured to: when the target fault type is an under-voltage fault, determining that the target control instruction is to disconnect the discharging switch (6); when the target fault type is a short-circuit fault, determining that the target control instruction is to disconnect the charging switch (5) and the discharging switch (6); when the target fault type is an over-voltage fault, determining that the target control instruction is to disconnect the charging switch (5); when the target fault type is a charging overcurrent fault, determining that the target control instruction is to disconnect the charging switch (5); when the target fault type is a discharging overcurrent fault, determining that the target control instruction is to disconnect the discharging switch (6); when the target fault type is an overtemperature fault or a thermal runaway fault, determining that the target control instruction is to disconnect the charging switch (5) and the discharging switch (6).

8. The battery management system of claim 1, wherein, The battery management system further comprises a communication component (7) and a fault light (8); The communication component (7) is electrically connected with the controller (3) and the fault light (8), respectively; The controller (3) is further configured to: when the state information meets a target state condition, send a target indication signal to the fault lamp (8) through the communication component (7) to make the fault lamp (8) emit a light signal based on the target indication signal.

9. A method of battery management, characterized by, The method is applied to a battery management system, and the battery management system comprises a low-voltage battery (1), a detection component (2), a controller (3), a memory (4), a charging switch (5), and a discharging switch (6), and the method comprises the following steps: The detection component (2) detects state information of the low-voltage battery (1), wherein the state information comprises a current, a voltage, and a battery cell temperature, and the state information is sent to the controller (3); The controller (3) stores the received state information in the memory (4), determines fault information based on the state information meeting a state condition when the state information meets a target state condition, stores the fault information in the memory (4), and controls the charging switch (5) and / or the discharging switch (6) based on the fault information.

10. The method of claim 9, wherein, When the state information meets a target state condition, the controller (3) determines fault information based on the state information meeting a state condition, which comprises: When a target state condition exists in a first correspondence relationship between a pre-stored state condition, a state information range, and a fault level, and current received state information meets the target state condition, in the first correspondence relationship, a target fault level corresponding to the target state condition and a target state information range to which the current received state information belongs is determined; Based on a second correspondence relationship between a pre-stored state condition and a fault type, a target fault type corresponding to the target state condition is determined; The target fault type and the target fault level are determined as the fault information.

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