Battery error equalization fault diagnosis method and related equipment

Abstract

The invention provides a battery error equalization fault diagnosis method and related equipment, and relates to the field of batteries. According to the scheme, when equalization control is carried out on a target battery monomer, an integral result of a difference value between the voltage of the target battery monomer and the voltage of the lowest battery monomer within a certain time period before and after equalization control is carried out on the target battery monomer is obtained; the method comprises the following steps: respectively recording the two integral results as a first integral result and a second integral result, comparing the first integral result with the second integral result, judging whether an equalization fault occurs or not based on a comparison result, and executing a preset strategy when the equalization fault occurs, for example, the strategy can generate prompt information for representing the position of a mistakenly-equalized battery. Therefore, whether the battery has an equalization fault or not can be effectively judged, and maintenance can be guided.

Description

Technical Field

[0001] The present invention relates to the technical field of batteries, and particularly to a method for diagnosing battery mis-balancing faults and related devices. Background Art

[0002] A Battery Management System (BMS for short) is an integrated circuit system mainly used to monitor and control the state of a battery system to ensure the normal operation and safe use of the battery. The BMS collects information on the power battery system and controls and gives early warnings according to the state of the battery system to ensure the safe and reliable use of the battery system in a vehicle. In electric vehicles, a master-slave BMS architecture is generally adopted, and the master-slave BMS includes a main control module and multiple slave control modules. In the division of labor of the battery balancing function, the main control module mainly formulates a balancing strategy and sends battery balancing control instructions to the slave control modules according to the set battery positions; the slave control modules mainly collect the voltage information of the batteries according to the set battery positions and simultaneously perform specific balancing control on the batteries.

[0003] The master-slave BMS architecture has strong flexibility and can support the design of large-scale battery packs, but it will also bring a series of problems, such as incorrect matching of the position numbers of the balanced monomers, which will lead to a series of problems. For example, Figure 1 As shown, the slave control modules default to collect voltage and perform balancing control in the order of monomers numbered 0 to 15 from left to right, and the main control module also defaults to send balancing control instructions in the order of monomers numbered 0 to 15 from left to right. In this case, the normal balancing control function can be carried out. But as Figure 2 shown, the slave control modules default to collect voltage and perform balancing control in the order of monomers numbered 0 to 15 from left to right, while the main control module sends balancing control instructions in the order of monomers numbered 15 to 0 from left to right; similarly, as Figure 3 shown, the slave control modules default to collect voltage and perform balancing control in the order of monomers numbered 15 to 0 from left to right, while the main control module sends balancing control instructions in the order of monomers numbered 0 to 15 from left to right. This may result in overcharge and over-discharge safety accidents such as continuously charging the monomer with a high voltage and continuously discharging the monomer with a low voltage. As Figure 2 shown, if the slave control module feedbacks that the voltage of the leftmost monomer No. 0 is too high, after the main control receives the information that the voltage of "No. 0" monomer is too high and sends the balancing control instruction for the "No. 0" monomer, and on the main control side, "0" corresponds to the position of the 15th monomer of the slave control, so the slave control module actually performs a discharging balancing operation on the 15th monomer.

[0004] Therefore, how to effectively detect whether the battery has mis-balancing control has become one of the technical problems that need to be urgently solved by those skilled in the art. Summary of the Invention

[0005] In view of this, embodiments of the present invention provide a method for diagnosing battery mis - equalization faults and related devices to effectively detect whether the battery has mis - equalization control.

[0006] To achieve the above object, embodiments of the present invention provide the following technical solutions:

[0007] A method for diagnosing battery mis - equalization faults includes:

[0008] Obtain the battery cell voltage output by the slave module;

[0009] Judge whether the battery cell voltage is greater than the set value;

[0010] When the battery cell voltage is greater than the set value, based on a preset rule, screen out the target battery cells that need to be equalized;

[0011] Integrate the difference between the voltage of the target battery cell and the lowest battery cell voltage, and record it as the first integration result;

[0012] Perform equalization control on the target battery cells;

[0013] Obtain the integration of the difference between the voltage of the target battery cell after equalization control and the lowest battery cell voltage, and record it as the second integration result;

[0014] Judge whether the first integration result is less than the second integration result;

[0015] When the first integration result is less than the second integration result, determine that an equalization fault has occurred and execute a preset strategy.

[0016] Optionally, in the above - mentioned method for diagnosing battery mis - equalization faults, after screening out the target battery cells that need to be equalized based on a preset rule, it further includes:

[0017] Obtain the identity identifier of the target battery cell;

[0018] The execution of the preset strategy includes:

[0019] Generate a prompt message for characterizing the mis - equalization fault, and at least include the identity identifier of the target battery cell in the prompt message.

[0020] Optionally, in the above - mentioned method for diagnosing battery mis - equalization faults, integrating the difference between the voltage of the target battery cell and the lowest battery cell voltage includes:

[0021] Integrate the difference between the voltage of the target battery cell and the lowest battery cell voltage within a preset time period;

[0022] Obtaining the integral of the difference between the voltage of the target battery cell after obtaining balanced control and the voltage of the lowest battery cell, including:

[0023] Obtaining the integral of the difference between the voltage of the target battery cell and the voltage of the lowest battery cell within a preset time period after obtaining balanced control of the target battery cell.

[0024] Optionally, in the above method for diagnosing battery mis-balancing faults, the number of target battery cells is N, and N is a positive integer not less than 1;

[0025] Judging whether the first integral result is less than the second integral result includes:

[0026] Respectively judging whether the first integral result corresponding to each target battery cell is less than the corresponding second integral result.

[0027] Optionally, in the above method for diagnosing battery mis-balancing faults, before integrating the difference between the voltage of the target battery cell and the voltage of the lowest battery cell, it further includes:

[0028] Judging whether a target instruction is obtained. When the target instruction is obtained, execute the steps: integrating the difference between the voltage of the target battery cell and the voltage of the lowest battery cell and subsequent steps;

[0029] When the target instruction is not obtained, perform balanced control on the target battery cell.

[0030] Optionally, in the above method for diagnosing battery mis-balancing faults, before integrating the difference between the voltage of the target battery cell and the voltage of the lowest battery cell, it further includes:

[0031] Judging whether it is the first time to determine that the voltage of the battery cell is greater than the set value. If it is the first time to determine that the voltage of the battery cell is greater than the set value, execute the steps: integrating the difference between the voltage of the target battery cell and the voltage of the lowest battery cell and subsequent steps;

[0032] If it is not the first time to determine that the voltage of the battery cell is greater than the set value, perform balanced control on the target battery cell.

[0033] Optionally, in the above method for diagnosing battery mis-balancing faults, judging whether the first integral result is less than the second integral result includes:

[0034] Correcting the first integral result by using an error correction coefficient;

[0035] Judging whether the corrected first integral result is less than the second integral result.

[0036] A device for diagnosing battery mis-balancing faults, including:

[0037] The slave module interaction unit is used to obtain the battery cell voltage output by the slave module;

[0038] The first judgment unit is used to judge whether the battery cell voltage is greater than the set value;

[0039] The target recognition unit is used to screen out the target battery cells to be balanced based on preset rules when the battery cell voltage is greater than the set value;

[0040] The first integration unit is used to integrate the difference between the voltage of the target battery cell and the lowest battery cell voltage, and record it as the first integration result;

[0041] The balancing unit is used to perform balancing control on the target battery cells;

[0042] The second integration unit is used to obtain the integration of the difference between the voltage of the target battery cell after balancing control and the lowest battery cell voltage, and record it as the second integration result;

[0043] The second judgment unit is used to judge whether the first integration result is less than the second integration result;

[0044] The fault warning unit is used to determine that a balancing fault occurs and execute a preset strategy when the first integration result is less than the second integration result.

[0045] A battery management system includes at least one processor and a memory connected to the processor, wherein:

[0046] The memory is used to store a computer program;

[0047] The processor is used to execute the computer program so that the electronic device can implement any of the above battery misbalancing fault diagnosis methods.

[0048] A vehicle includes the above battery management system.

[0049] Based on the above technical solutions, in the above solutions provided by the embodiments of the present invention, when performing balancing control on the target battery cells, the integration results of the differences between the voltages of the target battery cells and the lowest battery cell voltage within a certain period of time before and after the balancing control of the target battery cells are obtained, and are respectively recorded as the first integration result and the second integration result. By comparing the first integration result and the second integration result, it is judged whether a balancing fault occurs based on the comparison result. When a balancing fault occurs, a preset strategy is executed. For example, the strategy can be to generate a prompt message for characterizing the position of the misbalanced battery. Thus, it can effectively judge whether a balancing fault occurs in the battery and guide the maintenance. Description of the Drawings

[0050] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only the embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on the provided drawings.

[0051] Figure 1 Schematic diagram of the information transmission scenario between the master control module and the slave empty module when the positions of the battery cells are correctly matched;

[0052] Figure 2 Schematic diagram of the information transmission scenario between the master control module and the slave empty module when the positions of the battery cells are incorrectly matched;

[0053] Figure 3 Schematic diagram of the information transmission scenario between the master control module and the slave empty module when the positions of the battery cells are incorrectly matched;

[0054] Figure 4 Schematic flow chart of a method for diagnosing battery mis - equalization faults provided by an embodiment of the present application;

[0055] Figure 5 Schematic flow chart of a method for diagnosing battery mis - equalization faults provided by another embodiment of the present application;

[0056] Figure 6 Schematic flow chart of a method for diagnosing battery mis - equalization faults provided by still another embodiment of the present application;

[0057] Figure 7 Schematic analysis scenario diagram of a method for diagnosing battery mis - equalization faults provided by an embodiment of the present application;

[0058] Figure 8 Schematic structural diagram of a device for diagnosing battery mis - equalization faults provided by an embodiment of the present application. Detailed implementation manners

[0059] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of them. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0060] First, explain the professional technical terms involved in the present application:

[0061] Battery Balancing: Using power electronics technology to keep the voltage deviation of lithium-ion battery cells or battery packs within the expected range, so as to ensure that each battery cell maintains the same state during normal use and avoid overcharging and over-discharging. In products, a passive balancing strategy is generally adopted, that is, the excess energy of the battery with a higher voltage in the battery pack is consumed through a resistive load to reduce its voltage.

[0062] Vehicle EEPROM (Electrically Erasable Programmable read only memory): An electronic storage device used in automotive applications. It is a non-volatile memory that can retain stored data when the vehicle power is turned off.

[0063] Master control module or master control board: Used for calculating battery status, monitoring total voltage and total current, controlling the pre-charge circuit, formulating balancing strategies, making balancing decisions, etc.

[0064] Slave control module or slave control board: Used to monitor the voltage and temperature of the battery and implement specific balancing control on the battery.

[0065] Driving cycle: Generally, the process of vehicle power-on - driving - parking - power-off is regarded as one driving cycle.

[0066] To solve the problem of incorrect battery balancing control, this proposal presents a method to determine whether the position selection of the balanced cell is correct based on the change in the integral value of the difference between the voltage of the balanced cell and the voltage of the lowest battery cell within a certain period of time before and after balancing. Through integration, the difference can be accumulated, which is convenient for detecting the changes before and after the balance is turned on; the integral value of the difference between the voltage of this cell and the voltage of the lowest battery cell within a period of time before the balance is turned on is updated in real time. If the integral value of the difference between the voltage of this cell and the voltage of the lowest battery cell does not decrease significantly after the balance is turned on, an incorrect balance fault is reported.

[0067] Specifically, refer to Figure 4 , this embodiment of the application discloses a method for diagnosing incorrect battery balancing faults. This method can be applied to the master control module of the battery balancing system. This method includes:

[0068] Step S101: Obtain the voltage of the battery cells output by the slave control module.

[0069] During the battery balancing control process, the slave control module needs to detect the voltages of individual battery cells in the battery. By monitoring the individual cell voltages in real time, abnormal states can be identified. Through threshold judgment, the protection mechanism can be triggered in a timely manner (such as cutting off the charging path) to avoid battery thermal runaway or permanent damage caused by the individual cell voltage exceeding the safe range. The slave control module can collect the voltages of individual battery cells through a resistor voltage division network, convert the collected voltages of individual battery cells into voltage signals that can be recognized by the master control module, and upload them to the master control module.

[0070] Step S102: Determine whether the voltage of the individual battery cell is greater than the set value.

[0071] After obtaining the voltages of individual battery cells in the battery, compare the voltage of the individual battery cell with the set value to determine whether the voltage of the individual battery cell is greater than the set value. When it is greater than the set value, it indicates that battery balancing control is required. When the voltages of all individual battery cells are greater than the set value, it indicates that battery balancing control is not required. Among them, the size of the set value can be set according to the design requirements of the battery. For example, the set value can be 3.8V or others, and the set values corresponding to different specifications of batteries can be different.

[0072] Step S103: When the voltage of the individual battery cell is greater than the set value, screen out the target battery cells that need to be balanced based on preset rules.

[0073] When battery balancing control is required, it is necessary to make a balancing decision according to the pre-configured balancing strategy, screen out one or more battery cells that need to be balanced, and use all the screened battery cells as target battery cells. When screening target battery cells, the target battery cells can be screened from multiple battery cells in the battery based on the status information of the battery cells, such as temperature, internal resistance, etc., or other information. At this time, the screened target battery cells can include battery cells with voltages exceeding the set limit, but can also include battery cells with voltages not exceeding the limit but deviating from the group average.

[0074] Step S104: Integrate the difference between the voltage of the target battery cell and the voltage of the lowest battery cell, and record it as the first integration result.

[0075] After determining the target battery cells, compare the voltage of the target battery cells with the voltage of the lowest battery cell in the battery and record the integration result. When recording the integration result, integrate the difference between the voltage of the target battery cell and the voltage of the lowest battery cell in the most recent period of time (such as 30 minutes or other durations) to obtain an integration limit array, and record this integration limit array as the first integration result, that is, integrate the difference between the voltage of the target battery cell and the voltage of the lowest battery cell within a preset duration to obtain the first integration result.

[0076] Step S105: Perform balancing control on the target battery cell.

[0077] Step S106: Obtain the integral of the difference between the voltage of the target battery cell after balancing control and the voltage of the lowest battery cell, denoted as the second integral result.

[0078] After performing balancing control on the target battery cell for a period of time, within a certain period of this integral (the same integral duration as that corresponding to the first integral result, such as 30 min), the difference between the voltage of the target battery cell and the voltage of the lowest battery cell is denoted as the second integral result. That is, obtain the integral of the difference between the voltage of the target battery cell and the voltage of the lowest battery cell within a preset duration after balancing control of the target battery cell to obtain the second integral result.

[0079] Step S107: Determine whether the first integral result is less than the second integral result.

[0080] After obtaining the first integral result and the second integral result, compare the values at the same positions in the first integral result and the second integral result. If the value of the first integral result at this position is less than the second integral result, it indicates that the balancing control does not play a role in optimizing the battery, and this balancing control is incorrect. If the value of the first integral result at this position is not less than the second integral result, it indicates that the balancing control is effective.

[0081] Step S108: When the first integral result is less than the second integral result, determine that a balancing fault has occurred and execute a preset strategy.

[0082] The preset strategy may refer to an alarm strategy for reporting a balancing fault prompt message. That is, when the first integral result is less than the second integral result at the same position, determine that a balancing fault has occurred and report the balancing fault to prompt a re-verification of the battery cell matching information of the main control module and the slave control module.

[0083] In the above solution, when performing balancing control on the target battery cell, obtain the integral results of the differences between the voltage of the target battery cell and the voltage of the lowest battery cell within a certain period before and after the balancing control of the target battery cell, denoted as the first integral result and the second integral result respectively. By comparing the first integral result and the second integral result, determine whether a balancing fault has occurred based on the comparison result. When a balancing fault occurs, execute a preset strategy. For example, the strategy can be to generate a prompt message for characterizing the position of the mis-balanced battery. Thus, it is possible to effectively determine whether a balancing fault has occurred in the battery and guide the maintenance.

[0084] In the technical solution disclosed in this embodiment, in order to prompt the user which battery cell has an equalization failure during equalization control, in this solution, after screening out the target battery cells to be equalized based on a preset rule, it further includes: obtaining the identity identifier of the target battery cell, and the identity identifier may include the number, corresponding position, etc. of the target battery cell. At this time, executing the preset strategy includes: generating a prompt message for characterizing the mis-equalization failure, and the prompt message at least includes the identity identifier of the target battery cell. The user can quickly determine which battery has an equalization failure during equalization control through the identity identifier.

[0085] In the technical solution disclosed in this embodiment, the number of target battery cells is the number of battery cells that meet the preset rule. In this solution, the number of target battery cells is denoted as N, and N is a positive integer not less than 1; in step S104 and step S107, the first integral result and the second integral result corresponding to each target battery cell will be calculated respectively. At this time, when judging whether the first integral result is less than the second integral result, it is necessary to judge whether the first integral result corresponding to each target battery cell is less than the corresponding second integral result respectively. If there is any battery cell whose first integral result is less than its corresponding second integral result, it is considered that the battery has an equalization failure.

[0086] In this embodiment, the diagnostic method for battery mis-equalization failure can be executed only once when the battery is first used. If it is detected at this time that the battery has no equalization failure, it can indicate that the installation order of all battery cells in the battery is correct. If there is an equalization failure, it is necessary to remind the staff to check the order of the battery cells in the battery. This solution can be triggered actively by the user or by the system.

[0087] Regarding the active trigger by the user, see Figure 5 , in the above solution, before integrating the difference between the voltage of the target battery cell and the voltage of the lowest battery cell, it further includes:

[0088] Step S201: Judge whether a target instruction is obtained. When the target instruction is obtained, execute the steps: integrate the difference between the voltage of the target battery cell and the voltage of the lowest battery cell and subsequent steps; when the target instruction is not obtained, perform equalization control on the target battery cell. In this embodiment, the user can actively test whether the battery has an equalization failure. During the high-load operation of the battery, the user can send a target instruction to the main control module, and the user can send the target instruction to the main control module at any time.

[0089] Regarding the active trigger by the system, see Figure 6, before integrating the difference between the voltage of the target battery cell and the lowest battery cell voltage, it further includes:

[0090] Step S301: Determine whether it is the first time to determine that the battery cell voltage is greater than the set value. If it is the first time to determine that the battery cell voltage is greater than the set value, execute the steps: integrate the difference between the voltage of the target battery cell and the lowest battery cell voltage and subsequent steps; if it is not the first time to determine that the battery cell voltage is greater than the set value, perform equalization control on the target battery cell. In this embodiment, since the battery cells in the battery are arranged and installed in a certain order, as long as one of them goes wrong, the positions of all the battery cells will be wrong. As long as one position is correct, the positions of the other battery cells are correct. Therefore, it is only necessary to judge once whether there is an equalization fault in the battery to determine whether the positions of all the battery cells in the battery are correct (when there is no equalization fault, all battery positions are correct; when there is an equalization fault, all battery positions are wrong).

[0091] In this embodiment, a corresponding correction coefficient can be configured for batteries of different specifications, and the error correction coefficients corresponding to batteries of different specifications are different. For example, the error correction coefficient corresponding to a certain specification of battery can be 0.95. At this time, judging whether the first integration result is less than the second integration result includes: correcting the first integration result with the error correction coefficient corresponding to the battery, and then judging whether the corrected first integration result is less than the second integration result.

[0092] As Figure 7 shown, integrate the difference between the battery cell voltage of a target battery cell that needs to be equalized and the lowest battery cell voltage within a preset time period before the real-time integration equalization is turned on (such as 30 min) to obtain a first integration result S1 (calculated by a moving integrator with a 30-min time window); integrate the difference between the target battery cell voltage and the lowest battery cell voltage within a preset integration time period after the equalization is turned on (such as 30 min) to obtain a second integration result S2. Compare the magnitudes of the first integration result S1 and the second integration result S2 to determine whether the position of the selected target battery cell for equalization is correct.

[0093] In this embodiment, a diagnostic device for battery misequalization fault is disclosed. For the specific working content of each unit in the device, please refer to the content of the above method embodiment.

[0094] Next, the diagnostic device for battery misequalization fault provided by the embodiment of the present invention will be described. The diagnostic device for battery misequalization fault described below can be correspondingly referred to the diagnostic method for battery misequalization fault described above.

[0095] See Figure 8, the diagnostic device for battery misbalancing faults may include:

[0096] The slave control module interaction unit 10 is configured to obtain the battery cell voltages output by the slave control module;

[0097] The first judgment unit 20 is configured to judge whether the battery cell voltage is greater than a set value;

[0098] The target identification unit 30 is configured to, when the battery cell voltage is greater than the set value, screen out the target battery cells to be balanced based on a preset rule;

[0099] The first integration unit 40 is configured to integrate the difference between the voltage of the target battery cell and the lowest battery cell voltage, and record it as the first integration result;

[0100] The balancing unit 50 is configured to perform balancing control on the target battery cells;

[0101] The second integration unit 60 is configured to obtain the integration of the difference between the voltage of the target battery cell after balancing control and the lowest battery cell voltage, and record it as the second integration result;

[0102] The second judgment unit 70 is configured to judge whether the first integration result is less than the second integration result;

[0103] The fault warning unit 80 is configured to, when the first integration result is less than the second integration result, determine that a balancing fault occurs and execute a preset strategy.

[0104] Corresponding to the above method, the fault warning unit is further configured to obtain the identity identifier of the target battery cell. At this time, the execution of the preset strategy includes: generating a prompt message for characterizing the misbalancing fault, and the prompt message at least includes the identity identifier of the target battery cell.

[0105] A battery management system includes at least one processor and a memory connected to the processor, wherein:

[0106] The memory is used to store a computer program;

[0107] The processor is used to execute the computer program so that the electronic device can implement any one of the above battery misbalancing fault diagnostic methods.

[0108] A vehicle includes the above battery management system. The battery management system can be an ECU (Electronic Control Unit), a VCU (Vehicle Control Unit), an MCU (MicroController Unit), an HCU (Hybrid Control Unit), etc.

[0109] For the convenience of description, when describing the above systems, they are described as various modules according to their functions. Of course, when implementing the present invention, the functions of each module can be implemented in one or more software and / or hardware.

[0110] Each embodiment in this specification is described in a progressive manner. For the same or similar parts between each embodiment, reference can be made to each other. The key point of each embodiment is to illustrate the differences from other embodiments. In particular, for a system or a system embodiment, since it is basically similar to a method embodiment, the description is relatively simple. For the relevant parts, reference can be made to the partial description of the method embodiment. The systems and system embodiments described above are merely illustrative. The units described as separate components may or may not be physically separated. The components shown as units may or may not be physical units, that is, they may be located in one place or distributed to multiple network units. Some or all of the modules can be selected according to actual needs to achieve the purpose of the solution of this embodiment. A person of ordinary skill in the art can understand and implement it without creative work.

[0111] Those skilled in the art can further realize that the units and algorithm steps of each example described in combination with the embodiments disclosed in this article can be implemented by electronic hardware, computer software, or a combination of the two. To clearly illustrate the interchangeability of hardware and software, the composition and steps of each example have been generally described according to functions in the above description. Whether these functions are executed in a hardware or software manner depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered to exceed the scope of the present invention.

[0112] The steps of the method or algorithm described in combination with the embodiments disclosed in this article can be directly implemented by hardware, a software module executed by a processor, or a combination of the two. The software module can be placed in a random access memory (RAM), memory, read-only memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, register, hard disk, removable disk, CD-ROM, or any other form of storage medium known in the technical field.

[0113] It should also be noted that, in this document, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device comprising a series of elements not only includes those elements, but also includes other elements not expressly listed, or elements inherent to such process, method, article or device. Without further limitation, an element defined by the statement "comprising an..." does not exclude the presence of additional identical elements in the process, method, article or device comprising the said element.

[0114] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be obvious to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A diagnostic method for battery misbalancing faults, characterized in that, Including: Obtain the battery cell voltage output by the slave module; Judge whether the battery cell voltage is greater than the set value; When the battery cell voltage is greater than the set value, screen the target battery cells to be balanced based on preset rules; Integrate the difference between the voltage of the target battery cell and the lowest battery cell voltage, and record it as the first integration result; Perform balancing control on the target battery cells; Obtain the integration of the difference between the voltage of the target battery cell after balancing control and the lowest battery cell voltage, and record it as the second integration result; Judge whether the first integration result is less than the second integration result; When the first integration result is less than the second integration result, determine that a balancing failure occurs and execute a preset strategy.

2. The diagnostic method for battery misbalancing faults according to claim 1, characterized in that After screening the target battery cells to be balanced based on preset rules, it further includes: Obtain the identity identifier of the target battery cell; The execution of the preset strategy includes: Generate a prompt message for characterizing the misbalancing failure, and at least the identity identifier of the target battery cell is included in the prompt message.

3. The diagnostic method for battery mis - equalization fault according to claim 1, characterized in that, Integrating the difference between the voltage of the target battery cell and the lowest battery cell voltage includes: Integrate the difference between the voltage of the target battery cell and the lowest battery cell voltage within a preset time period; Obtaining the integration of the difference between the voltage of the target battery cell after balancing control and the lowest battery cell voltage includes: Obtain the integration of the difference between the voltage of the target battery cell and the lowest battery cell voltage within a preset time period after balancing control of the target battery cell.

4. The diagnostic method for battery misbalancing faults according to claim 1, characterized in that, The number of the target battery cells is N, and N is a positive integer not less than 1; Judging whether the first integration result is less than the second integration result includes: Respectively judge whether the first integration result corresponding to each target battery cell is less than the corresponding second integration result.

5. The diagnostic method for battery misbalancing faults according to claim 1, characterized in that Before integrating the difference between the voltage of the target battery cell and the lowest battery cell voltage, it further includes: Judge whether a target instruction is obtained. When the target instruction is obtained, execute the steps: integrate the difference between the voltage of the target battery cell and the lowest battery cell voltage and subsequent steps; When the target instruction is not obtained, perform balancing control on the target battery cells.

6. The diagnostic method for battery misbalancing fault according to claim 1, wherein, Before integrating the difference between the voltage of the target battery cell and the lowest battery cell voltage, it further includes: Judge whether it is the first time to determine that the battery cell voltage is greater than the set value. If it is the first time to determine that the battery cell voltage is greater than the set value, execute the steps: integrate the difference between the voltage of the target battery cell and the lowest battery cell voltage and subsequent steps; If it is not the first time to determine that the battery cell voltage is greater than the set value, perform balancing control on the target battery cells.

7. The diagnostic method for battery mis-balancing faults according to claim 1, wherein, Judging whether the first integration result is less than the second integration result includes: Correct the first integration result by using an error correction coefficient; Judge whether the corrected first integration result is less than the second integration result.

8. A diagnostic device for battery mis - equalization faults, characterized in that, Including: Slave module interaction unit, used to obtain the battery cell voltage output by the slave module; First judgment unit, used to judge whether the battery cell voltage is greater than the set value; A target recognition unit, configured to, when the voltage of the battery cell is greater than a set value, screen out target battery cells to be balanced based on a preset rule; A first integration unit, configured to integrate the difference between the voltage of the target battery cell and the voltage of the lowest battery cell, and record it as a first integration result; An equalization unit, configured to perform equalization control on the target battery cell; A second integration unit, configured to obtain the integration of the difference between the voltage of the target battery cell after equalization control and the voltage of the lowest battery cell, and record it as a second integration result; A second judgment unit, configured to judge whether the first integration result is less than the second integration result; A fault warning unit, configured to, when the first integration result is less than the second integration result, determine that an equalization fault occurs and execute a preset strategy.

9. A battery management system, characterized in that, Comprising at least one processor and a memory connected to the processor, wherein: The memory is used for storing a computer program; The processor is used for executing the computer program so that the battery management system can implement the battery mis - equalization fault diagnosis method according to any one of claims 1 to 7.

10. A vehicle, characterized in that, Comprising the battery management system according to claim 9.

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