Battery cell anomaly detection method and device, vehicle, storage medium and product
Patent Information
- Application Number
- CN202411396088.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-08
- Publication Date
- 2025-01-14
Smart Images
Figure CN119310410A_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the technical field of power batteries, and in particular to a method, device, vehicle, storage medium and product for detecting abnormality of a battery cell. Background Art
[0002] As an important power source for new energy vehicles, lithium-ion batteries have been widely used in the new energy vehicle industry due to their advantages such as being green, environmentally friendly, recyclable, and small in size. The battery system used in electric vehicles is usually composed of multiple cells connected in series and parallel to achieve the accumulation of voltage and capacity. In high-voltage battery systems, the insulation performance of each series or parallel cell is a critical safety factor. If any unit in the battery system fails in insulation, it may cause the insulation of the entire battery pack to fail, which in turn causes leakage of the entire vehicle. In severe cases, it may even cause electric shock accidents to the driver and passengers, resulting in casualties.
[0003] In the related technology, an insulation detection module is generally added at the battery system level to monitor the insulation resistance of the total positive and negative electrodes of the battery relative to the shell in real time, so as to judge the insulation condition of the entire battery system. However, this method has certain limitations. It can only evaluate the overall insulation state of the total positive and negative electrodes of the battery to the shell from a macro perspective, but cannot accurately identify which specific battery cell has an insulation problem; in addition, it is also impossible to diagnose the insulation state of the positive and negative electrodes inside a single battery cell to the aluminum shell, which may miss the opportunity to diagnose early minor insulation failures, leading to more serious insulation safety accidents later. Summary of the invention
[0004] The present application provides a method, device, vehicle, storage medium and product for detecting abnormality of a battery cell to solve the problem of how to accurately detect abnormal battery cells.
[0005] The first aspect of the present application provides a method for detecting abnormalities in a battery cell, comprising the following steps: identifying one or more battery cells of a power battery; calculating a target voltage ratio between the positive and negative poles in each battery cell and the outer aluminum shell of the power battery; and determining a target battery cell with an abnormal insulation state based on the target voltage ratio.
[0006] Optionally, calculating the target voltage ratio between the positive and negative electrode posts in each battery cell and the outer shell of the power battery includes: calculating a first voltage value between the positive electrode post in each battery cell and the outer shell of the power battery and a second voltage value between the negative electrode post and the outer shell; and calculating the target voltage ratio based on the first voltage value and the second voltage value.
[0007] Optionally, identifying a target battery cell with an abnormal insulation state based on a target voltage ratio includes: obtaining a first resistance value and a second resistance value between the positive and negative electrode posts in the battery cell and the outer shell of the power battery in a normal state, and calculating a constant resistance ratio in a normal state based on the first resistance value and the second resistance value; determining a target resistance ratio between the positive and negative electrode posts in each battery cell and the outer shell of the power battery based on the target voltage ratio; and identifying the target battery cell with an abnormal insulation state based on the target resistance ratio and the constant resistance ratio.
[0008] Optionally, the target battery cell with abnormal insulation state is identified according to the target resistance ratio and the constant resistance ratio, including: if the target resistance ratio is less than the constant resistance ratio, and the resistance between the positive electrode pole and the outer shell of the power battery is less than a first resistance value, then it is determined that the state of the insulation layer between the positive electrode pole and the outer shell of the power battery is abnormal; if the target resistance ratio is greater than the constant resistance ratio, and the resistance between the negative electrode pole and the outer shell of the power battery is less than a second value, then it is determined that the insulation layer between the negative electrode pole and the outer shell of the power battery is abnormal.
[0009] Optionally, a target resistance ratio between the positive and negative poles in each battery cell and the outer shell of the power battery is determined according to the target voltage ratio, including: obtaining a correspondence between the voltage ratio and resistance ratio of the positive and negative poles in the battery cell and the outer shell of the power battery; and determining a target resistance ratio between the positive and negative poles in each battery cell and the outer shell of the power battery according to the corresponding relationship and the target voltage ratio.
[0010] Optionally, the corresponding relationship is:
[0011]
[0012] Among them, V1 is the voltage value between the positive electrode post of the battery cell and the outer shell, V2 is the voltage value between the positive electrode post of the battery cell and the outer shell; R1 is the resistance value between the positive electrode post of the battery cell and the outer shell, R2 is the resistance value between the negative electrode post of the battery cell and the outer shell, and K is a constant preset ratio.
[0013] The second aspect of the present application provides a battery cell abnormality detection device, including: an identification module, used to identify one or more battery cells of a power battery; a calculation module, used to calculate the target voltage ratio between the positive and negative poles in each battery cell and the outer aluminum shell of the power battery; a determination module, used to determine the target battery cell with abnormal insulation state according to the target voltage ratio.
[0014] Optionally, the calculation module is further used to: calculate a first voltage value between the positive electrode post and the outer shell of the power battery and a second voltage value between the negative electrode post and the outer shell in each battery cell; and calculate a target voltage ratio based on the first voltage value and the second voltage value.
[0015] Optionally, the determination module is further used to obtain a first resistance value and a second resistance value between the positive and negative electrode posts in the battery cell and the outer shell of the power battery under normal conditions, and calculate a constant resistance ratio under normal conditions based on the first resistance value and the second resistance value; determine a target resistance ratio between the positive and negative electrode posts in each battery cell and the outer shell of the power battery based on the target voltage ratio; and identify a target battery cell with an abnormal insulation state based on the target resistance ratio and the constant resistance ratio.
[0016] Optionally, the determination module is further used to determine that the state of the insulation layer between the positive electrode post and the outer shell of the power battery is abnormal if the target resistance ratio is less than the constant resistance ratio and the resistance between the positive electrode post and the outer shell of the power battery is less than the first resistance value; if the target resistance ratio is greater than the constant resistance ratio and the resistance between the negative electrode post and the outer shell of the power battery is less than the second resistance value, then determine that the state of the insulation layer between the negative electrode post and the outer shell of the power battery is abnormal.
[0017] Optionally, the determination module is further used to obtain the correspondence between the voltage ratio and resistance ratio of the positive and negative electrode posts in the battery cell and the outer shell of the power battery; and determine the target resistance ratio between the positive and negative electrode posts in each battery cell and the outer shell of the power battery according to the correspondence and the target voltage ratio.
[0018] Optionally, the corresponding relationship is:
[0019]
[0020] Among them, V1 is the voltage value between the positive electrode post of the battery cell and the outer shell, V2 is the voltage value between the positive electrode post of the battery cell and the outer shell; R1 is the resistance value between the positive electrode post of the battery cell and the outer shell, R2 is the resistance value between the negative electrode post of the battery cell and the outer shell, and K is a constant preset ratio.
[0021] A third aspect of the present application provides a vehicle, comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement a method for detecting abnormalities in a battery cell as described in the above embodiment.
[0022] A fourth aspect of the present application provides a computer-readable storage medium having a computer program or instruction stored thereon. When the computer program or instruction is executed, it is used to implement the abnormality detection method of the battery cell as in the above embodiment.
[0023] The fifth aspect of the present application provides a computer program product, including: a computer program or instructions, which, when executed, implements the battery cell abnormality detection method as described in the above embodiment.
[0024] Therefore, this application has at least the following beneficial effects:
[0025] The embodiment of the present application achieves direct monitoring of the insulation status between the positive and negative electrodes inside a single battery cell and the aluminum shell by determining the voltage value between the positive electrode post, the negative electrode post and the outer aluminum shell of each battery cell. The specific battery cell with insulation problems can be accurately located, thereby effectively avoiding safety accidents caused by insulation failure.
[0026] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS
[0027] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:
[0028] Figure 1 A flowchart of a method for detecting abnormality of a battery cell according to an embodiment of the present application;
[0029] Figure 2 This is an example diagram of a square aluminum shell battery provided according to an embodiment of the present application;
[0030] Figure 3 An electrical circuit diagram formed by the positive and negative poles and the outer aluminum shell of the battery according to one embodiment of the present application;
[0031] Figure 4 is a block diagram of a battery cell abnormality detection device according to an embodiment of the present application;
[0032] Figure 5 It is a schematic diagram of the structure of a vehicle according to an embodiment of the present application. DETAILED DESCRIPTION
[0033] Embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present application, and should not be construed as limiting the present application.
[0034] The following describes the abnormality detection method, device, vehicle and storage medium of the battery cell of the embodiment of the present application with reference to the accompanying drawings. In response to the problems mentioned in the above background technology, the present application provides a method for detecting abnormality of battery cells. In this method, by determining the voltage value between the positive pole, the negative pole and the outer aluminum shell of each battery cell, the insulation state between the positive and negative poles inside a single battery cell and the aluminum shell is directly monitored, and the specific battery cell with insulation problems can be accurately located, thereby effectively avoiding safety accidents caused by insulation failure. Thus, the problem of how to accurately detect abnormal battery cells is solved.
[0035] Specifically, Figure 1 A schematic flow chart of a method for detecting abnormality of a battery cell provided in an embodiment of the present application.
[0036] like Figure 1 As shown, the abnormality detection method of the battery cell includes the following steps:
[0037] In step S101 , one or more cells of a power battery are identified.
[0038] In step S102, a target voltage ratio between the positive and negative electrode posts in each battery cell and the outer aluminum shell of the power battery is calculated.
[0039] Specifically, if Figure 2 As shown, in the square aluminum shell battery, 1 is the outer aluminum shell of the aluminum shell battery, 2 is the positive electrode column, 3 is the negative electrode column, and there is an insulating member 4, 5 between the positive and negative electrode columns 2, 3 and the aluminum shell respectively. The resistance values of the insulating members 4, 5 are R1, R2 respectively, and the resistance value range of R1 and R2 is between 1kΩ and 10MΩ, because the resistance value here needs to be selected with a larger value to ensure the insulation effect between the positive and negative electrode columns and the outer aluminum shell of the battery.
[0040] In one embodiment of the present application, the target voltage ratio between the positive and negative poles in each battery cell and the outer shell of the power battery is calculated, including: calculating a first voltage value between the positive pole in each battery cell and the outer shell of the power battery and a second voltage value between the negative pole and the outer shell; calculating the target voltage ratio based on the first voltage value and the second voltage value.
[0041] Specifically, in an actual battery system, voltage detection lines are provided on the positive pole, negative pole and outer aluminum shell of each battery cell. The electrical circuit formed by the positive and negative poles of the battery and the outer aluminum shell of the battery is as follows: Figure 2 The three detection lines on each battery detect that the voltage between the positive electrode and the aluminum shell is V1, and the voltage between the negative electrode and the aluminum shell is V2, thereby obtaining the target voltage ratio of the battery cell.
[0042] In step S103, a target battery cell having an abnormal insulation state is determined according to the target voltage ratio.
[0043] It can be understood that, unlike the traditional method of evaluating the insulation performance of the entire battery system only from a macroscopic perspective, the embodiment of the present application realizes direct monitoring of the insulation status between the positive and negative electrodes inside a single battery cell and the aluminum shell by setting voltage detection lines on the positive electrode post, the negative electrode post and the outer aluminum shell of each battery cell. The specific battery cell with insulation problems can be accurately located, thereby improving the accuracy and efficiency of fault diagnosis.
[0044] In one embodiment of the present application, a target battery cell with an abnormal insulation state is identified based on a target voltage ratio, including: obtaining a first resistance value and a second resistance value between the positive and negative poles in the battery cell and the outer shell of the power battery in a normal state, and calculating a constant resistance ratio in a normal state based on the first resistance value and the second resistance value; determining a target resistance ratio between the positive and negative poles in each battery cell and the outer shell of the power battery based on the target voltage ratio; and identifying the target battery cell with an abnormal insulation state based on the target resistance ratio and the constant resistance ratio.
[0045] It is understandable that when the battery system is in normal working condition, the first resistance value (denoted as R1) between the positive pole and the aluminum shell of each battery cell and the second resistance value (denoted as R2) between the negative pole and the aluminum shell reflect the insulation performance of the positive and negative electrodes inside the battery cell to the aluminum shell. Under normal circumstances, R1 and R2 should be kept in a relatively stable and high range (for example, 1kΩ to 10MΩ) to ensure good insulation effect.
[0046] In an embodiment of the present application, the embodiment of the present application can obtain the correspondence between the voltage ratio and resistance ratio of the positive and negative poles in the battery cell and the outer shell of the power battery; determine the target resistance ratio between the positive and negative poles in each battery cell and the outer shell of the power battery according to the correspondence and the target voltage ratio.
[0047] Among them, the corresponding relationship is:
[0048]
[0049] Among them, V1 is the voltage value between the positive electrode post of the battery cell and the outer shell, V2 is the voltage value between the positive electrode post of the battery cell and the outer shell; R1 is the resistance value between the positive electrode post of the battery cell and the outer shell, R2 is the resistance value between the negative electrode post of the battery cell and the outer shell, and K is a constant preset ratio.
[0050] Furthermore, the preferred K value is 1 / 3, 1 / 2, 1, 2, 3. Under normal circumstances, the voltage ratio K of the positive pole and the negative pole of the battery cell to the aluminum shell is constant, and then when some abnormal conditions occur inside the battery cell, this K value will change. If the insulation layer fails inside the battery cell, whether it is a problem with the positive electrode or the negative electrode or both, the corresponding resistance value will change, thereby affecting the value of K.
[0051] The embodiment of the present application can compare the actually measured target resistance ratio with the previously determined constant resistance ratio K. If it is found that the target resistance ratio of a certain battery cell deviates significantly from K, it can be determined that the insulation state of the battery cell is abnormal. This deviation may be caused by partial or complete failure of the insulation layer between the positive and negative electrodes of the winding core and the aluminum shell inside the battery cell. Once the existence of the insulation problem is confirmed, the BMS will report the situation to the VCU in a timely manner so that further safety measures can be taken, such as warning the driver to check the relevant components or replace the faulty battery cell.
[0052] In one embodiment of the present application, a target battery cell with an abnormal insulation state is identified based on a target resistance ratio and a constant resistance ratio, including: if the target resistance ratio is less than the constant resistance ratio, and the resistance between the positive electrode post and the outer shell of the power battery is less than a first resistance value, it is determined that the state of the insulation layer between the positive electrode post and the outer shell of the power battery is abnormal; if the target resistance ratio is greater than the constant resistance ratio, and the resistance between the negative electrode post and the outer shell of the power battery is less than a second resistance value, it is determined that the insulation layer between the negative electrode post and the outer shell of the power battery is abnormal; if the constant resistance ratio changes, it is determined that the insulation layer between the positive and negative electrode posts and the outer shell of the power battery is abnormal.
[0053] In the embodiment of the present application, the insulation layer between the positive electrode column of the battery core and the aluminum shell fails. At this time, the resistance R1 between the positive electrode column of the battery cell and the aluminum shell is reduced to R1', and the following mathematical relationship will appear:
[0054]
[0055] The insulation layer between the negative electrode of the battery cell and the aluminum shell fails. At this time, the resistance R2 between the negative electrode of the battery cell and the aluminum shell is reduced to R2', and the following mathematical relationship will appear:
[0056]
[0057] The insulation layer between the positive and negative electrodes of the battery core and the aluminum shell fails. At this time, the resistance R1 and R2 between the positive and negative electrodes of the battery and the aluminum shell are reduced to R1' and R2'. Due to the decrease in these two resistance values, the ratio of R1' / R2' will change, and the following mathematical relationship will appear:
[0058]
[0059] By online monitoring of the voltage ratio of V1 / V2, the insulation status of the positive and negative electrodes inside the battery and the shell can be inferred. Once an abnormal value is found, it will be reported to the VCU through the BMS to warn the driver to handle it.
[0060] Furthermore, the insulating parts 4 and 5 of the embodiment of the present application can be plastic parts, such as PP, PE, ABS, or some semiconductor ceramic materials, such as barium titanate, vanadium oxide, etc.
[0061] According to the battery cell abnormality detection method proposed in the embodiment of the present application, by determining the voltage value between the positive pole, negative pole and the outer aluminum shell of each battery cell, direct monitoring of the insulation status between the positive and negative poles inside a single battery cell and the aluminum shell is achieved, and the specific battery cell with insulation problems can be accurately located, thereby effectively avoiding safety accidents caused by insulation failure.
[0062] Next, the abnormality detection device for a battery cell proposed in an embodiment of the present application is described with reference to the accompanying drawings.
[0063] Figure 4 It is a block diagram of a battery cell abnormality detection device according to an embodiment of the present application.
[0064] like Figure 4 As shown, the abnormality detection device 10 of the battery cell includes: an identification module 100 , a calculation module 200 and a determination module 300 .
[0065] Among them, the identification module 100 is used to identify one or more battery cells of the power battery; the calculation module 200 is used to calculate the target voltage ratio between the positive and negative poles in each battery cell and the outer aluminum shell of the power battery; the determination module 300 is used to determine the target battery cell with abnormal insulation status according to the target voltage ratio.
[0066] In one embodiment of the present application, the calculation module 200 is used to: calculate a first voltage value between the positive electrode post and the outer shell of the power battery and a second voltage value between the negative electrode post and the outer shell in each battery cell; and calculate a target voltage ratio based on the first voltage value and the second voltage value.
[0067] In one embodiment of the present application, the determination module 300 is used to obtain the first resistance value and the second resistance value between the positive and negative poles in the battery cell and the outer shell of the power battery under normal conditions, and calculate the constant resistance ratio under normal conditions based on the first resistance value and the second resistance value; determine the target resistance ratio between the positive and negative poles in each battery cell and the outer shell of the power battery according to the target voltage ratio; and identify the target battery cell with abnormal insulation state according to the target resistance ratio and the constant resistance ratio.
[0068] In one embodiment of the present application, the determination module 300 is used to determine that the state of the insulation layer between the positive electrode post and the outer shell of the power battery is abnormal if the target resistance ratio is less than the constant resistance ratio and the resistance between the positive electrode post and the outer shell of the power battery is less than the first resistance value; if the target resistance ratio is greater than the constant resistance ratio and the resistance between the negative electrode post and the outer shell of the power battery is less than the second resistance value, then it is determined that the insulation layer between the negative electrode post and the outer shell of the power battery is abnormal; if the constant resistance ratio changes, then it is determined that the insulation layer between the positive and negative electrode posts and the outer shell of the power battery is abnormal.
[0069] In one embodiment of the present application, the determination module 300 is used to obtain the correspondence between the voltage ratio and resistance ratio of the positive and negative poles in the battery cell and the outer shell of the power battery; and determine the target resistance ratio between the positive and negative poles in each battery cell and the outer shell of the power battery according to the correspondence and the target voltage ratio.
[0070] In one embodiment of the present application, the corresponding relationship is:
[0071]
[0072] Among them, V1 is the voltage value between the positive electrode post of the battery cell and the outer shell, V2 is the voltage value between the positive electrode post of the battery cell and the outer shell; R1 is the resistance value between the positive electrode post of the battery cell and the outer shell, R2 is the resistance value between the negative electrode post of the battery cell and the outer shell, and K is a constant preset ratio.
[0073] It should be noted that the above explanation of the embodiment of the method for detecting abnormality of a battery cell is also applicable to the abnormality detection device for a battery cell of this embodiment, and will not be repeated here.
[0074] According to the battery cell abnormality detection device proposed in the embodiment of the present application, by determining the voltage value between the positive pole, the negative pole and the outer aluminum shell of each battery cell, direct monitoring of the insulation status between the positive and negative poles inside a single battery cell and the aluminum shell is achieved, and the specific battery cell with insulation problems can be accurately located, thereby effectively avoiding safety accidents caused by insulation failure.
[0075] Figure 5 A schematic diagram of the structure of a vehicle provided in an embodiment of the present application. The vehicle may include:
[0076] Memory 401 , processor 402 , and a computer program stored in the memory 401 and executable on the processor 402 .
[0077] When the processor 402 executes the program, the abnormality detection method of the battery cell provided in the above embodiment is implemented.
[0078] Furthermore, the vehicle also includes:
[0079] The communication interface 403 is used for communication between the memory 401 and the processor 402 .
[0080] The memory 401 is used to store computer programs that can be executed on the processor 402 .
[0081] The memory 401 may include a high-speed RAM (Random Access Memory) memory, and may also include a non-volatile memory, such as at least one disk memory.
[0082] If the memory 401, the processor 402 and the communication interface 403 are implemented independently, the communication interface 403, the memory 401 and the processor 402 can be connected to each other through a bus and communicate with each other. The bus can be an ISA (Industry Standard Architecture) bus, a PCI (Peripheral Component Interconnect) bus or an EISA (Extended Industry Standard Architecture) bus, etc. The bus can be divided into an address bus, a data bus, a control bus, etc. For ease of representation, Figure 4 Only one thick line is used in the diagram, but this does not mean that there is only one bus or only one type of bus.
[0083] Optionally, in a specific implementation, if the memory 401, the processor 402 and the communication interface 403 are integrated on a chip, the memory 401, the processor 402 and the communication interface 403 can communicate with each other through an internal interface.
[0084] The processor 402 may be a CPU (Central Processing Unit), or an ASIC (Application Specific Integrated Circuit), or one or more integrated circuits configured to implement the embodiments of the present application.
[0085] An embodiment of the present application also provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the above-mentioned method for detecting abnormalities in a battery cell.
[0086] An embodiment of the present application further provides a computer program product, including: a computer program or instructions, which, when executed, implements the abnormality detection method for a battery cell as described in the above embodiment.
[0087] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms are not necessarily directed to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or N embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.
[0088] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of this application, "N" means at least two, such as two, three, etc., unless otherwise clearly and specifically defined.
[0089] Any process or method description in a flowchart or otherwise described herein may be understood to represent a module, fragment or portion of code comprising one or more executable instructions for implementing the steps of a custom logical function or process, and the scope of the preferred embodiments of the present application includes alternative implementations in which functions may not be performed in the order shown or discussed, including performing functions in a substantially simultaneous manner or in reverse order depending on the functions involved, which should be understood by technicians in the technical field to which the embodiments of the present application belong.
[0090] It should be understood that the various parts of the present application can be implemented by hardware, software, firmware or a combination thereof. In the above-mentioned embodiment, the N steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented by hardware, as in another embodiment, it can be implemented by any one of the following technologies known in the art or their combination: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array, a field programmable gate array, etc.
[0091] A person skilled in the art may understand that all or part of the steps in the method for implementing the above-mentioned embodiment may be completed by instructing related hardware through a program, and the program may be stored in a computer-readable storage medium, which, when executed, includes one or a combination of the steps of the method embodiment.
[0092] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations on the present application. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present application.
Claims
1. A method for detecting abnormality of a battery cell, characterized in that: The following steps are involved: Identify one or more cells of the power battery; Calculating a target voltage ratio between the positive and negative poles in each battery cell and the outer aluminum shell of the power battery; The target battery cell with abnormal insulation state is determined according to the target voltage ratio.
2. The method for detecting abnormality of a battery cell according to claim 1, characterized in that: Calculate the target voltage ratio between the positive and negative poles in each battery cell and the outer shell of the power battery, including Calculating a first voltage value between the positive electrode post and the outer shell of the power battery and a second voltage value between the negative electrode post and the outer shell in each battery cell; The target voltage ratio is calculated according to the first voltage value and the second voltage value.
3. The method for detecting abnormality of a battery cell according to claim 1, characterized in that: The step of determining the target battery cell with abnormal insulation state according to the target voltage ratio includes: Acquire a first resistance value and a second resistance value between the positive and negative electrode posts in the battery cell and the outer shell of the power battery in a normal state, and calculate a constant resistance ratio in the normal state according to the first resistance value and the second resistance value; Determining a target resistance ratio between the positive and negative electrode posts in each battery cell and the outer shell of the power battery according to the target voltage ratio; A target battery cell with an abnormal insulation state is identified according to the target resistance ratio and the constant resistance ratio.
4. The method for detecting abnormality of a battery cell according to claim 3, characterized in that: The method of identifying a target battery cell having an abnormal insulation state according to the target resistance ratio and the constant resistance ratio includes: If the target resistance ratio is less than the constant resistance ratio, and the resistance between the positive electrode post and the outer shell of the power battery is less than the first resistance value, it is determined that the state of the insulation layer between the positive electrode post and the outer shell of the power battery is abnormal; If the target resistance ratio is greater than the constant resistance ratio, and the resistance between the negative electrode post and the outer shell of the power battery is less than the second resistance value, it is determined that the insulation layer between the negative electrode post and the outer shell of the power battery is abnormal.
5. The method for detecting abnormality of a battery cell according to claim 3, characterized in that: The step of determining a target resistance ratio between the positive and negative electrode posts in each battery cell and the outer shell of the power battery according to the target voltage ratio includes: Obtaining a corresponding relationship between a voltage ratio and a resistance ratio of the positive and negative electrode posts in the battery cell and an outer shell of the power battery; The target resistance ratio between the positive and negative poles in each battery cell and the outer shell of the power battery is determined according to the corresponding relationship and the target voltage ratio.
6. The method for detecting abnormality of a battery cell according to claim 5, characterized in that: The corresponding relationship is: Among them, V1 is the voltage value between the positive electrode post of the battery cell and the outer shell, V2 is the voltage value between the positive electrode post of the battery cell and the outer shell; R1 is the resistance value between the positive electrode post of the battery cell and the outer shell, R2 is the resistance value between the negative electrode post of the battery cell and the outer shell, and K is a constant preset ratio.
7. A battery cell abnormality detection device, characterized in that: include: An identification module, used to identify one or more cells of a power battery; A calculation module, used to calculate a target voltage ratio between the positive and negative poles in each battery cell and the outer aluminum shell of the power battery; A determination module is used to determine a target battery cell with abnormal insulation status according to the target voltage ratio.
8. A vehicle, characterized in that: include: A memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the method for detecting abnormality of a battery cell as described in any one of claims 1 to 6.
9. A computer-readable storage medium having a computer program or instruction stored thereon, characterized in that: When the computer program or instruction is executed, the abnormality detection method for the battery cell according to any one of claims 1 to 6 is implemented.
10. A computer program product comprising: A computer program or instruction, characterized in that when the computer program or instruction is executed, it implements the abnormality detection method for the battery cell according to any one of claims 1 to 6.