Battery cell module detection method and device and test equipment

Abstract

The invention discloses a detection method and device of a battery cell module and test equipment. According to the method, two switch groups are arranged in the test equipment, each switch group comprises N switches, the switches are connected with the output ends of N battery cell monomers connected in series in a battery cell module, so that the detection of the battery cell monomers is realized, the state of each switch is adjusted in sequence, and the detection accuracy of the battery cell monomers is improved. And the detection voltage between the first common end and the second common end is obtained after each adjustment, so that the output voltage of each battery cell monomer or the output voltage after a plurality of battery cell monomers are connected in series can be accurately obtained. Through multiple detection voltage analysis, whether the battery cell module has a broken line problem or not can be detected, and whether a pseudo soldering problem exists or not can be judged, so that the detection precision and reliability are greatly improved; in addition, the process is controlled through a processor, automation can be achieved, limitation in traditional manual detection is eliminated, production efficiency is improved, and detection cost is reduced.

Description

Technical Field

[0001] The present invention relates to the field of power supply safety, and in particular to a detection method, device and testing equipment for a battery cell module. Background Art

[0002] In the field of battery cell manufacturing technology, the production of battery cell modules is a crucial link, and its quality directly affects the overall performance and safety of the battery cell. In the production process of battery cell modules, each battery cell needs to be accurately collected and tested to ensure that the quality and performance of all battery cell units meet the standards. The current battery cell module detection method mainly relies on manual operation. Inspectors usually use high-precision multimeters to measure the voltage of each string of battery cell modules one by one to determine whether the voltage difference between each battery cell is within the qualified range. This manual measurement method can only determine whether there is a disconnection problem in the battery cell collection line, and cannot accurately detect the situation of cold welding in the battery cell module. Cold welding may cause unstable performance or safety hazards of the battery cell module during use, and may eventually cause battery cell modules with quality problems to flow into the market, thereby affecting the overall performance and safety of the battery cell. In addition, the existing detection methods cannot be automated, resulting in low production efficiency and increased detection costs, which in turn affects the overall production benefits. Summary of the invention

[0003] The purpose of the present invention is to provide a detection method, device and testing equipment for a battery cell module. Through multiple detection voltage analyses, it is possible to detect not only whether the battery cell module has a broken wire problem, but also whether there is a cold soldering problem, thereby greatly improving the detection accuracy and reliability; in addition, the process is controlled by a processor and can be automated, eliminating the limitations of traditional manual detection, improving production efficiency and reducing detection costs.

[0004] On the one hand, the present application provides a method for detecting a battery cell module, which is applied to a processor in a test device, wherein the test device also includes two switch groups, each of which includes N switches, and the battery cell module includes N battery cells connected in series, wherein the first end of the i-th switch in the first switch group is connected to the first output end of the i-th battery cell, the first end of the i-th switch in the second switch group is connected to the second output end of the i-th battery cell, the second ends of the N switches in the first switch group are connected and serve as a first common end, and the second ends of the N switches in the second switch group are connected and serve as a second common end, 1≤i≤N, N>1, and i and N are both integers; the method for detecting the battery cell module includes:

[0005] Determine a switch adjustment strategy according to the detection requirements, and adjust the states of all the switches multiple times according to the switch adjustment strategy;

[0006] After each adjustment of the state of the switch is completed, a detection voltage between the first common terminal and the second common terminal is obtained and used as the output voltage of one of the battery cells corresponding to the current switch state or the output voltage of M battery cells connected in series, 1<M≤N, and M is an integer;

[0007] The detection result of the battery cell module is determined according to the detection voltage obtained by adjusting the state of the switch for multiple times.

[0008] Optionally, adjusting the states of all the switches multiple times according to the switch adjustment strategy includes:

[0009] Controlling the first switch in the first switch group to be closed and the Nth switch in the second switch group to be closed, and all switches except the first switch in the first switch group and the Nth switch in the second switch group to be opened;

[0010] Controlling the i-th switch in the first switch group and the i-th switch in the second switch group to be closed, and all switches except the two i-th switches to be opened, wherein i increases gradually from 1 to N in chronological order;

[0011] After each adjustment of the state of the switch is completed, the detection voltage between the first common terminal and the second common terminal is obtained and used as the output voltage of one of the battery cells corresponding to the current switch state or the output voltage of M battery cells connected in series, including:

[0012] After controlling the first switch in the first switch group to close and the Nth switch in the second switch group to close, obtaining the detection voltage between the first common terminal and the second common terminal and using it as the total voltage after the N battery cells are connected in series;

[0013] After controlling the i-th switch in the first switch group and the i-th switch in the second switch group to be closed, obtaining a detection voltage between the first common terminal and the second common terminal and using the detection voltage as a cell voltage of the i-th battery cell;

[0014] Determining the detection result of the battery cell module according to the detection voltage obtained by adjusting the state of the switch for multiple times includes:

[0015] The detection result of the battery cell module is determined according to the total voltage and the cell voltage of each of the battery cell cells.

[0016] Optionally, determining the detection result of the battery cell module according to the total voltage and the cell voltage of each of the battery cell cells includes:

[0017] Comparing the total voltage with a preset total voltage range, and determining whether there is an abnormality in the battery cell module according to the comparison result of the total voltage;

[0018] If an abnormality exists in the battery cell module, the cell voltage of each of the battery cell monomers is compared with a preset cell voltage range, and the abnormal position of the battery cell module is determined according to the comparison result of the cell voltage of each of the battery cell monomers.

[0019] Optionally, determining whether there is an abnormality in the battery cell module according to the comparison result of the total voltage includes:

[0020] If the total voltage is continuously less than the minimum value in the preset total voltage range within the preset time, it is determined that there is a disconnection between at least two of the battery cells, and / or that there is at least one abnormal battery cell;

[0021] If the total voltage is not continuously less than the minimum value in the preset total voltage range within the preset time, and the total voltage fluctuates, then a first difference between the maximum voltage value and the minimum voltage value during the total voltage fluctuation process is calculated, and it is determined whether the first difference is within the preset fluctuation voltage range;

[0022] If the first difference is not within the preset fluctuation voltage range, it is determined that a cold solder joint exists between at least two of the battery cell monomers.

[0023] Optionally, the battery module further includes N+1 fuses, the first end of the i-th fuse is connected to the first output end of the i-th battery cell, the first end of the N+1-th fuse is connected to the second output end of the N-th battery cell, the second end of the i-th fuse is connected to the first end of the i-th switch in the first switch group, and the i-th switch in the second switch group is connected to the second end of the i+1-th fuse;

[0024] Determining whether there is an abnormality in the battery cell module according to the comparison result of the total voltage includes:

[0025] If the total voltage is continuously less than the minimum value in the preset total voltage range within the preset time, it is determined that there is a disconnection between at least two of the battery cells, and / or there is at least one abnormal battery cell, and / or the first fuse is disconnected, and / or the N+1th fuse is disconnected;

[0026] If the total voltage is not continuously less than the minimum value in the preset total voltage range within the preset time, and the total voltage fluctuates, then a first difference between the maximum voltage value and the minimum voltage value during the total voltage fluctuation process is calculated, and it is determined whether the first difference is within the preset fluctuation voltage range;

[0027] If the first difference is not within the preset fluctuation voltage range, it is determined that there is a cold solder joint between at least two of the battery cells, and / or the first fuse is cold-blown, and / or the N+1th fuse is cold-blown.

[0028] Optionally, the testing device further includes a voltage dividing path provided between the first common terminal and the second common terminal; when i=N, after obtaining the detection voltage between the first common terminal and the second common terminal and using it as the cell voltage of the i-th battery cell, the testing device further includes:

[0029] Control all switches in the switch group to be turned off, control the voltage dividing path to be turned on, and again control the i-th switch in the first switch group and the i-th switch in the second switch group to be turned on, and all switches except the two i-th switches are turned off, and i gradually increases from 1 to N in chronological order;

[0030] After controlling the i-th switch in the first switch group and the i-th switch in the second switch group to be closed simultaneously, obtaining the i-th divided voltage value on the divided voltage path;

[0031] According to the i-th voltage division value and the i-th cell voltage, it is determined whether the i-th battery cell has a cold solder joint, and / or whether the i-th fuse and the i+1-th fuse have a cold blow.

[0032] Optionally, the voltage dividing path includes a first voltage dividing switch, a second voltage dividing switch and a first resistor, the first resistor is arranged between a first end of the first voltage dividing switch and a first end of the second voltage dividing switch, the second end of the first voltage dividing switch is connected to the first common end, and the second end of the second voltage dividing switch is connected to the second common end;

[0033] Controlling the conduction of the voltage dividing path includes:

[0034] The first voltage-dividing switch and the second voltage-dividing switch are controlled to be closed.

[0035] Optionally, the test device further includes a first main switch and a second main switch, wherein a first end of the first main switch is connected to a first output end of a first battery cell, a second end of the first main switch is connected to the first common end, a first end of the second main switch is connected to a second output end of an Nth battery cell, and a second end of the second main switch is connected to the second common end;

[0036] Determining a switch adjustment strategy according to the detection requirement, and before adjusting the states of all the switches multiple times according to the switch adjustment strategy, the detection method of the battery cell module further includes:

[0037] Controlling the first main switch to close, the second main switch to open, and all switches in the switch group to open, and obtaining a detection voltage between the first common terminal and the second common terminal to determine whether there is a stuck switch in the second switch group;

[0038] Controlling the second main switch to close, the first main switch to open, and all switches in the switch group to open, and obtaining a detection voltage between the first common terminal and the second common terminal to determine whether there is a sticky switch in the first switch group;

[0039] If there are no stuck switches in the first switch group and the second switch group, the process proceeds to the step of determining a switch adjustment strategy according to a detection requirement, and adjusting the states of all the switches multiple times according to the switch adjustment strategy.

[0040] On the other hand, the present application provides a battery cell module detection device, comprising:

[0041] Memory for storing computer programs;

[0042] A processor is used to implement the steps of the battery cell module detection method as described above when executing the computer program.

[0043] In another aspect, the present application provides a test device including a power supply, a processor, and two switch groups;

[0044] The power supply is respectively connected to the power supply terminal of the processor and the power supply terminals of the two switch groups;

[0045] Each of the switch groups includes N switches, the first end of the i-th switch in the first switch group is connected to the first output end of the i-th battery cell in the battery cell module, the first end of the i-th switch in the second switch group is connected to the second output end of the i-th battery cell, the second ends of the N switches in the first switch group are connected and serve as a first common end, the second ends of the N switches in the second switch group are connected and serve as a second common end, the battery cell module includes N battery cells connected in series, 1≤i≤N, N>1, and i and N are both integers;

[0046] The processor is used to implement the steps of the battery cell module detection method as described in any one of claims 1 to 8 when executing a computer program.

[0047] The present invention provides a detection method, device and test equipment for a battery module. The method realizes the detection of the battery cells by setting two switch groups in the test equipment, each switch group includes N switches, and these switches are connected to the output ends of N series-connected battery cells in the battery module. By adjusting the state of each switch in turn and obtaining the detection voltage between the first common end and the second common end after each adjustment, the output voltage of each battery cell or multiple battery cells connected in series can be accurately obtained. Through multiple detection voltage analysis, it is not only possible to detect whether there is a disconnection problem in the battery module, but also to determine whether there is a cold soldering problem, thereby greatly improving the accuracy and reliability of the detection; in addition, the process is controlled by a processor and can be automated, eliminating the limitations of traditional manual detection, improving production efficiency, and reducing detection costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] In order to more clearly illustrate the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0049] Figure 1 A schematic diagram of a flow chart of a method for detecting a battery cell module provided by the present invention;

[0050] Figure 2 A schematic diagram of circuit connection of a battery module and a test device provided by the present invention;

[0051] Figure 3 A flowchart of a specific implementation of a detection method for a battery cell module provided by the present invention;

[0052] Figure 4 A flowchart of a specific implementation of another method for detecting a battery cell module provided by the present invention;

[0053] Figure 5 This is a schematic diagram of a testing device provided by the present invention. DETAILED DESCRIPTION

[0054] The core of the present invention is to provide a detection method, device and testing equipment for a battery cell module. Through multiple detection voltage analyses, it is not only possible to detect whether the battery cell module has a broken wire problem, but also to determine whether there is a cold soldering problem, thereby greatly improving the detection accuracy and reliability; in addition, the process is controlled by a processor and can be automated, eliminating the limitations of traditional manual detection, improving production efficiency and reducing detection costs.

[0055] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0056] On the one hand, if Figure 1 and Figure 2 As shown, the present application provides a detection method for a battery cell module, which is applied to a processor in a test device. The test device also includes two switch groups, each switch group includes N switches, and the battery cell module includes N battery cells connected in series. The first end of the i-th switch in the first switch group is connected to the first output end of the i-th battery cell, the first end of the i-th switch in the second switch group is connected to the second output end of the i-th battery cell, the second ends of the N switches in the first switch group are connected and serve as a first common end, the second ends of the N switches in the second switch group are connected and serve as a second common end, 1≤i≤N, N>1, and i and N are both integers.

[0057] The principle of this test equipment is based on the detection and analysis of the single cell voltage of each battery cell in the battery cell module or the voltage after several battery cells are connected in series, and the comprehensive detection of the battery cell module is realized through the coordinated operation of two switch groups and the processor. The two switch groups can be two relays, each relay includes N relay contacts. Specifically, by controlling the processor to adjust the state of each switch in the two switch groups according to the detection requirements, each battery cell can be connected in turn under different combinations, and the voltage can be measured between the first common terminal and the second common terminal. The measured voltage data can be used to determine the output of each battery cell or several battery cells connected in series, so as to detect whether there are broken wires, cold welds or abnormal battery cells in the battery cell module, and realize efficient and accurate detection of the battery cell module.

[0058] The detection methods of battery cell modules include:

[0059] S11: determining a switch adjustment strategy according to the detection requirements, and adjusting the states of all switches multiple times according to the switch adjustment strategy;

[0060] In this step, the key to the detection method is to determine and implement an appropriate switch adjustment strategy to ensure accurate voltage measurement of each cell and its combination in the cell module. Figure 2As shown in the figure, the strategy can be determined by the host computer, which analyzes the detection requirements of the battery module and formulates a suitable switch adjustment plan. The host computer plans the test sequence and method for the battery cells and their combinations according to the specific detection goals and requirements (such as detecting broken wires, cold solder joints, etc.). Then, the host computer sends the generated switch adjustment strategy to the processor in the test equipment ( Figure 2 In the PLC in the control unit, the processor gradually controls the state of each switch in the switch group according to the received strategy, such as gradually connecting and disconnecting each battery cell in the battery module, or connecting multiple battery cells in series, so that after each state adjustment, the voltage of a specific battery cell or a group of battery cells can be measured.

[0061] By systematically adjusting the switch state, a wide range of cell voltage data can be collected under different voltage measurement conditions. This data not only provides necessary information for subsequent wire break detection, but also provides a basis for cold solder joint detection. The entire process is automatically controlled by the processor to ensure that the switch state is adjusted accurately and consistently, greatly reducing errors in manual operation, thereby providing reliable data support for further analysis of the performance of the cell module.

[0062] S12: After each switch state adjustment is completed, a detection voltage between the first common terminal and the second common terminal is obtained and used as an output voltage of a battery cell corresponding to the current switch state or an output voltage of M battery cells connected in series, where 1<M≤N, and M is an integer;

[0063] In this step, after each switch state adjustment is completed, the current cell state is determined by measuring the detection voltage between the first common terminal and the second common terminal. Specifically, through the previously set switch adjustment strategy, the states of multiple switches may combine different cell connection forms, which include the connection of a single cell or the connection of multiple cell monomers in series. For each connection form, the detection device (such as Figure 2 The multimeter in the figure will measure the corresponding voltage value between the two common terminals. This voltage value corresponds to the output voltage of a battery cell in the current switching state or the output voltage of M battery cells connected in series, where M is an integer greater than 1 and less than or equal to N, and N is the number of battery cells in the battery module.

[0064] In this way, this step can collect multiple voltage data points under different conditions. These data points not only reflect the working conditions of each battery cell, but also can identify possible abnormal conditions in the battery cell module by analyzing these voltage data, such as broken wires or poor solder joints. This method of multiple voltage collection and analysis greatly improves the accuracy and reliability of detection, and provides a solid foundation for subsequent analysis of detection results.

[0065] S13: Determine the detection result of the battery cell module according to the detection voltage obtained by adjusting the switch status for multiple times.

[0066] In this step, the detection result of the battery cell module is determined by comprehensively analyzing the voltage data obtained by adjusting the switch state multiple times. Specifically, the processor compares and evaluates the voltage data obtained by multiple measurements, identifies abnormal patterns or trends in the voltage, and thus infers the health status of the battery cell module. For example, if the voltage values ​​measured in multiple states are generally lower than the preset range, it may indicate that there is a disconnection of the battery cell; if the voltage data fluctuates significantly, it may indicate problems such as cold welding. By comprehensively analyzing these voltage data, the processor can accurately determine whether there is a broken wire, cold welding or other abnormal conditions in the battery cell module, and generate a detection report accordingly (or the processor feeds back the data to the test host computer connected to it, so that the test host computer can determine whether there is a broken wire, cold welding or other abnormal conditions in the battery cell module, and generate a detection report accordingly).

[0067] Through systematic voltage measurement and data analysis, this application not only improves the accuracy of detection, but also can effectively identify potential problems in the battery cell module to ensure that the quality and performance of the battery cell module meet the standards.

[0068] In summary, the detection method of the battery cell module provided by the present invention is to set two switch groups in the test equipment, each switch group includes N switches, and these switches are connected to the output ends of the N battery cells connected in series in the battery cell module, so as to realize the detection of the battery cells, and to accurately obtain the output voltage of each battery cell or multiple battery cells connected in series by adjusting the state of each switch in turn and obtaining the detection voltage between the first common terminal and the second common terminal after each adjustment. Through multiple detection voltage analysis, it is not only possible to detect whether there is a broken line problem in the battery cell module, but also to determine whether there is a cold soldering problem, thereby greatly improving the accuracy and reliability of the detection; in addition, the process is controlled by a processor and can be automated, eliminating the limitations of traditional manual detection, improving production efficiency, and reducing detection costs.

[0069] Based on the above embodiments:

[0070] In a preferred embodiment, the states of all switches are adjusted multiple times according to the switch adjustment strategy, including: controlling the first switch in the first switch group to be closed, and the Nth switch in the second switch group to be closed, and all switches except the first switch in the first switch group and the Nth switch in the second switch group are disconnected; controlling the i-th switch in the first switch group and the i-th switch in the second switch group to be closed, and all switches except the two i-th switches are disconnected, and i gradually increases from 1 to N in chronological order; after each switch state adjustment is completed, obtaining the detection voltage between the first common terminal and the second common terminal, and using it as the output voltage of a battery cell corresponding to the current switch state. The method comprises: controlling the first switch in the first switch group to be closed, and the Nth switch in the second switch group to be closed, obtaining the detection voltage between the first common terminal and the second common terminal, and using the detection voltage as the total voltage after the N battery cells are connected in series; controlling the i-th switch in the first switch group and the i-th switch in the second switch group to be closed, obtaining the detection voltage between the first common terminal and the second common terminal, and using the cell voltage of the i-th battery cell; determining the detection result of the battery cell module according to the detection voltages obtained by adjusting the states of the switches for multiple times, comprising: determining the detection result of the battery cell module according to the total voltage and the cell voltage of each battery cell.

[0071] In this preferred embodiment, the specific implementation of step S11 involves the operation of two switch groups. First, the first switch in the first switch group is controlled to be closed, and the Nth switch in the second switch group is controlled to be closed, while the other switches remain in the open state, so as to measure the total voltage of all N battery cells connected in series: the purpose of this step is to obtain the total voltage of the entire battery module, so as to provide benchmark data for subsequent voltage comparison and abnormality detection.

[0072] Next, the i-th switch in the first switch group and the i-th switch in the second switch group are controlled to close, and the other switches are opened, i is incremented from 1 to N in sequence: This operation allows the two common ends to connect to individual battery cells one by one, and measure the voltage of the i-th battery cell respectively, so as to obtain the cell voltage of each battery cell. This strategy of gradually adjusting the switch state allows each battery cell to be measured independently, ensuring the accuracy and integrity of the data.

[0073] Then for step S12, after controlling the first switch in the first switch group to close and the Nth switch in the second switch group to close, the detection voltage between the first common terminal and the second common terminal can be measured, and this detection voltage represents the total voltage of all N battery cells connected in series. Furthermore, after controlling the i-th switch in the first switch group and the i-th switch in the second switch group to close, the cell voltage of the i-th battery cell can be obtained, ensuring that the cell voltages are measured one by one, so that the state of each battery cell can be accurately recorded.

[0074] Accordingly, all collected voltage data will be used to analyze the overall status of the battery module. By comparing the total voltage and the voltage of each battery cell, it can be determined whether there is an abnormality in the battery module. For example, if the total voltage is lower than the preset range and the cell voltage is normal, it may indicate that the battery module has a disconnection or other problems; if the cell voltage is abnormal, it may indicate that there is a problem with the cell itself or there are problems such as cold soldering.

[0075] Through this comprehensive inspection and analysis method, any potential defects in the battery cell module can be accurately identified, ensuring that the quality of the battery cell module meets the standards.

[0076] In a preferred embodiment, the detection result of the battery cell module is determined based on the total voltage and the single cell voltage of each battery cell, including: comparing the total voltage with a preset total voltage range, and determining whether there is an abnormality in the battery cell module based on the comparison result of the total voltage; if there is an abnormality in the battery cell module, comparing the single cell voltage of each battery cell with the preset single cell voltage range, and determining the abnormal position of the battery cell module based on the comparison result of the single cell voltage of each battery cell.

[0077] In this preferred embodiment, the result of detecting the battery cell module is based on the total voltage and the cell voltage of each battery cell, and a systematic comparison and analysis method is used to accurately determine the health status of the module. First, the total voltage is compared with the preset total voltage range. The preset total voltage range is based on the voltage characteristics of the battery cell module under normal working conditions. When the measured total voltage is lower than the lower limit of the preset total voltage range, it indicates that there is an abnormality in the battery cell module as a whole. This situation may be due to the problem of disconnection of some batteries in the battery cell module, which causes the overall voltage to fail to reach the normal value.

[0078] If the comparison result of the total voltage is abnormal, it is necessary to further analyze the cell voltage of each battery cell. By comparing the cell voltage of each battery cell with the preset cell voltage range, it is possible to identify which battery cells have voltage values ​​that deviate from the normal range. This comparison can reveal specific abnormalities, such as the voltage of some battery cells may be significantly lower than the normal value due to poor soldering or defects in the battery cell itself. By combining the data of these cell voltages, the abnormal position in the battery module can be accurately located, thereby determining which battery cell has a problem.

[0079] It can be seen that this embodiment can not only identify the health status of the entire battery module, but also accurately locate the problematic battery, thereby achieving refined troubleshooting and maintenance. Through this systematic detection and analysis method, the detection accuracy and reliability of the battery module can be effectively improved to ensure that its quality and performance meet the standards.

[0080] In a preferred embodiment, whether there is an abnormality in the battery cell module is determined based on the comparison result of the total voltage, including: if the total voltage is continuously less than the minimum value in the preset total voltage range within a preset time, it is determined that there is a disconnection between at least two battery cell monomers, and / or that there is at least one abnormal battery cell monomer; if the total voltage is not continuously less than the minimum value in the preset total voltage range within the preset time, and the total voltage fluctuates, then the first difference between the maximum voltage value and the minimum voltage value during the total voltage fluctuation process is calculated, and it is determined whether the first difference is within the preset fluctuation voltage range; if the first difference is not within the preset fluctuation voltage range, it is determined that there is a cold solder joint between at least two battery cell monomers.

[0081] This embodiment aims to limit several situations when it is determined that the battery module has an abnormality based on the total voltage. Specifically, one situation is that when the total voltage is continuously lower than the minimum value in the preset total voltage range within a preset time range, this situation usually indicates that there is a serious electrical problem in the battery module. Specifically, this may be due to a disconnection between at least two battery cells (for example, a broken wire or a disconnected weld at the battery cell connection) or an abnormality in at least one battery cell itself (such as a battery cell failure or performance degradation). This phenomenon of continuous low voltage is usually caused by a failure in the overall connection of the battery module or an individual battery cell.

[0082] Another case is that if the total voltage does not continue to be lower than the minimum value within the preset time, but fluctuates, it is necessary to further analyze the characteristics of the voltage fluctuation. Specifically, by calculating the first difference between the maximum voltage value and the minimum voltage value during the total voltage fluctuation, the amplitude of the voltage fluctuation can be evaluated. This difference is then compared with the preset fluctuation voltage range. If the first difference exceeds the preset fluctuation voltage range, it indicates that there is a cold solder joint problem in the battery cell module. Cold solder joints usually cause unstable connections of battery cell monomers, thereby causing voltage fluctuations. Therefore, exceeding the fluctuation range may be an indication of the presence of cold solder joints.

[0083] It can be seen that the method in this embodiment starts from the stability and fluctuation characteristics of the total voltage, which can accurately judge the health status of the battery module and identify potential disconnection and poor soldering problems. This systematic analysis method can ensure comprehensive and accurate fault detection of the battery module, thereby improving the reliability and efficiency of the overall detection.

[0084] In a preferred embodiment, the battery module further includes N+1 fuses, the first end of the ith fuse is connected to the first output end of the ith battery cell, the first end of the N+1th fuse is connected to the second output end of the Nth battery cell, the second end of the ith fuse is connected to the first end of the ith switch in the first switch group, and the ith switch in the second switch group is connected to the second end of the i+1th fuse; determining whether there is an abnormality in the battery module according to the comparison result of the total voltage includes: if the total voltage is continuously less than the minimum value in the preset total voltage range within a preset time, determining that at least two battery cells are abnormal There is a disconnection between the cells, and / or there is at least one abnormal battery cell, and / or the first fuse is disconnected, and / or the N+1th fuse is disconnected; if the total voltage is not continuously less than the minimum value in the preset total voltage range within the preset time, and the total voltage fluctuates, then a first difference between the maximum voltage value and the minimum voltage value during the total voltage fluctuation process is calculated, and it is determined whether the first difference is within the preset fluctuating voltage range; if the first difference is not within the preset fluctuating voltage range, it is determined that there is a cold solder joint between at least two battery cells, and / or the first fuse is broken, and / or the N+1th fuse is broken.

[0085] In this preferred embodiment, in order to comprehensively detect abnormal conditions in the battery module, especially considering the fuses that may be set in the module, the detection process needs to distinguish different fault sources in detail. Specifically, when the battery module includes N battery cells connected in series, N+1 fuses are usually set accordingly, and each fuse is arranged to protect the battery system and ensure its safe and stable operation. Specifically, the connection relationship between the fuse and the battery cell can be referred to Figure 2 The first end of the i-th fuse is connected to the first output end of the i-th battery cell, and the first end of the N+1-th fuse is connected to the second output end of the N-th battery cell. This arrangement enables the fuse to play a key role in the overall circuit of the battery module.

[0086] When testing the battery module, determine whether there is an abnormality based on the comparison result of the total voltage. If the total voltage continues to be lower than the minimum value in the preset total voltage range within the preset time, this usually indicates that there is a serious electrical fault in the module. In this case, there may be the following problems: disconnection between at least two battery cells, abnormality of at least one battery cell itself, disconnection of the first fuse, or disconnection of the N+1th fuse. Since these two fuses are located in the total circuit of N battery cells in series, their disconnection will also cause the total voltage to decrease, so the status of these fuses needs to be considered additionally.

[0087] If the total voltage does not continue to be lower than the minimum value within the preset time, but there is a significant voltage fluctuation, the first difference between the maximum voltage value and the minimum voltage value during the total voltage fluctuation is calculated, and if the first difference exceeds the preset range, it indicates that there is a cold solder joint or other electrical problem. At this time, it is also necessary to consider the possible cold solder joint of the fuse, that is, the cold solder joint of the first fuse or the N+1th fuse, because the cold solder joint between the battery cells usually leads to voltage instability, and the cold solder joint of these fuses may also affect the overall voltage fluctuation, especially in the series circuit.

[0088] By comprehensively considering the state of the battery cell, the disconnection and virtual disconnection of the fuse, the health state of the battery cell module can be accurately judged. This detailed detection method can ensure the stable and safe performance of the battery cell module and improve the accuracy and reliability of the overall detection.

[0089] In one embodiment, if the total voltage is continuously lower than the minimum value in the preset total voltage range within a preset time, the disconnection location, abnormal cell, and whether the fuse is disconnected can be determined by the cell voltage of each cell.

[0090] If there is a disconnection between two cells in a cell module, it will usually cause the voltage of these cells to be significantly lower than that of other cells, or the voltage of some cells to be zero or very low. This is because the disconnection will interrupt the current path and affect the normal measurement of voltage. Therefore, by comparing the voltage data of the cell cells, if it is found that the voltage of some cell cells is much lower than that of other cells (or by comparing the cell voltage of the cell cells with the preset cell voltage range, if the cell voltage is much lower than the preset cell voltage range), it may indicate that there is a disconnection between these cell cells.

[0091] If the voltage of a cell is abnormally lower or higher than a preset cell voltage range, the cell is determined to be abnormal, which may be caused by an internal fault, performance degradation or other electrical abnormalities in the cell.

[0092] If the voltage of the first battery cell is zero or very low, while the voltages of subsequent battery cells are normal, it may indicate that the first fuse has been disconnected, because the disconnection of the first fuse will cause the first battery cell to fail to work normally, resulting in its voltage being zero.

[0093] If the voltage of the last battery cell is zero or very low, while the voltages of other battery cells are normal, it may indicate that the N+1th fuse has been disconnected, because the disconnection of the N+1th fuse will cause the last battery cell to fail to work properly, causing its voltage to be zero.

[0094] If the voltage of the middle cell is abnormally low, but the voltage of the first and last cell is normal, it may mean that the fuse of some of the middle cells is broken. In this case, the specific location can be determined by checking the status of each fuse one by one.

[0095] This method can accurately locate the specific location of the disconnection in the battery module, determine the abnormal battery cell, and determine whether the fuse is disconnected. This detailed analysis can effectively improve the detection accuracy and reliability of the battery module.

[0096] In a preferred embodiment, the testing device also includes a voltage-dividing path arranged between the first common terminal and the second common terminal; when i=N, after obtaining the detection voltage between the first common terminal and the second common terminal and using it as the cell voltage of the i-th battery cell, it also includes: controlling all switches in the switch group to be disconnected, controlling the voltage-dividing path to be turned on, and again controlling the i-th switch in the first switch group and the i-th switch in the second switch group to be closed, and all switches except the two i-th switches are disconnected, and i gradually increases from 1 to N in chronological order; after controlling the i-th switch in the first switch group and the i-th switch in the second switch group to be closed at the same time, obtaining the i-th voltage-dividing value on the voltage-dividing path; determining whether the i-th battery cell has a cold solder joint according to the i-th voltage-dividing value and the i-th cell voltage, and / or whether the i-th fuse and the i+1-th fuse are falsely broken.

[0097] In this preferred embodiment, in order to more accurately detect whether the battery cells and fuses in the battery cell module have a cold solder joint or a cold blow problem, the test device introduces a voltage divider path setting.

[0098] Specifically, when i=N, that is, when the last battery cell is tested, the test device first obtains the detection voltage between the first common terminal and the second common terminal, and uses it as the cell voltage of the Nth battery cell. After obtaining the cell voltage of the Nth battery cell, the test device will disconnect the switches in all switch groups to ensure that there are no other current paths in the circuit; the purpose of this step is to isolate the battery cell to be tested to avoid interference from other circuits. Next, the voltage-dividing path is controlled to be turned on, and the i-th switch in the first switch group and the i-th switch in the second switch group are reclosed at the same time, and the other switches remain disconnected. At this time, when the voltage-dividing path and the i-th battery cell form a loop, the voltage on the voltage-dividing path is the i-th voltage-dividing value borne by the voltage-dividing path when the voltage-dividing path supplies power to the i-th battery cell.

[0099] After obtaining the voltage division value, by comparing the ith voltage division value with its ith cell voltage, it is possible to effectively determine whether the Nth cell has a cold solder joint or a cold disconnection problem. If the Nth cell has a cold solder joint, it will usually cause a large difference between its ith voltage division value and the ith cell voltage, which is manifested as a voltage division value that is significantly lower than expected or fluctuates abnormally. Similarly, if the fuse of the ith cell (ith fuse) or the fuse of the next cell (i+1 fuse) is cold disconnected, it will also affect the voltage division value of the cell.

[0100] Specifically, the voltage of the ith cell is differentiated from the ith voltage divider value, and the obtained voltage difference is judged. If the voltage difference is within the threshold range, the test is qualified. Otherwise, the ith fuse or the i+1th fuse may be falsely blown, or the ith battery cell may have a poor solder joint. Which fuse is falsely blown or where the poor solder joint exists needs to be comprehensively judged based on the ith voltage divider value of the adjacent battery cell and the voltage of the ith cell.

[0101] This method can accurately identify the phenomenon of cold soldering and the problem of false fuse breaking by combining the comparison of single cell voltage and voltage division value. The voltage division path provides an additional voltage reference point, making the detection process more comprehensive and reliable. Through this detailed analysis, the fault detection accuracy of the battery module can be effectively improved, ensuring that the status of each battery cell and its related fuse is accurately evaluated, thereby optimizing the overall quality and safety of the battery module.

[0102] In a preferred embodiment, the voltage dividing path includes a first voltage dividing switch, a second voltage dividing switch and a first resistor, the first resistor is arranged between the first end of the first voltage dividing switch and the first end of the second voltage dividing switch, the second end of the first voltage dividing switch is connected to the first common end, and the second end of the second voltage dividing switch is connected to the second common end; controlling the voltage dividing path to be turned on includes: controlling the first voltage dividing switch and the second voltage dividing switch to be closed.

[0103] In this preferred embodiment, the voltage-dividing path is composed of a first voltage-dividing switch, a second voltage-dividing switch, and a first resistor arranged therebetween. The first resistor is used to generate voltage division during the measurement process. The first voltage-dividing switch provides a contact point in the control circuit so that the voltage signal can be measured through resistor voltage division. The second voltage-dividing switch has a similar function to the first voltage-dividing switch and is used to form another part of the voltage measurement. The first voltage-dividing switch and the second voltage-dividing switch can also be implemented by relays, such as two relay contacts in one relay, or two relays, and each voltage-dividing switch is a relay contact in each relay.

[0104] The specific principle is: when the voltage-dividing path is controlled to be turned on, the first voltage-dividing switch and the second voltage-dividing switch must be closed first, so that the current can pass through the first resistor, thereby forming a stable voltage-dividing path. Voltage-dividing principle: Through the set first resistor, the voltage-dividing path can distribute the voltage of the battery cell to the resistor. By closing the first voltage-dividing switch and the second voltage-dividing switch, it is ensured that the current forms a voltage divider when it flows through the first resistor, so that the voltage value can be read on the voltage-dividing path.

[0105] If there is a cold solder joint or a broken joint in the battery cell, the voltage distribution in the voltage divider path will change, causing the measured voltage divider value to be inconsistent with the expected value (such as large fluctuations). In this way, the test device can identify the abnormality of the voltage divider value and judge whether there is a cold solder joint or a broken joint in the battery cell or its fuse.

[0106] In a preferred embodiment, the testing device further includes a first main switch and a second main switch, the first end of the first main switch is connected to the first output end of the first battery cell, the second end of the first main switch is connected to the first common end, the first end of the second main switch is connected to the second output end of the Nth battery cell, and the second end of the second main switch is connected to the second common end; before determining the switch adjustment strategy according to the detection requirements, and adjusting the states of all switches multiple times according to the switch adjustment strategy, the detection method of the battery cell module further includes: controlling the first main switch to close, the second main switch to open, and all switches in the switch group to open, and obtaining a detection voltage between the first common end and the second common end to determine whether there are any stuck switches in the second switch group; controlling the second main switch to close, the first main switch to open, and all switches in the switch group to open, and obtaining a detection voltage between the first common end and the second common end to determine whether there are any stuck switches in the first switch group; if there are no stuck switches in both the first switch group and the second switch group, entering the step of determining the switch adjustment strategy according to the detection requirements, and adjusting the states of all switches multiple times according to the switch adjustment strategy.

[0107] In this preferred embodiment, in order to ensure the accuracy of the detection result of the battery module, a first main switch and a second main switch are introduced into the test equipment to detect whether there are sticky switches in the switch group before detecting the battery module.

[0108] The function of the first main switch is to affect the conduction of the path between the first output terminal of the first battery cell and the first common terminal by turning on or off the first main switch in the circuit. The function of the second main switch is similar to the first main switch, and is used to control the conduction of the path between the second output terminal of the Nth battery cell and the second common terminal. The first main switch and the second main switch can be implemented by the contacts of a relay, or other controllable switches, which are not limited in this application.

[0109] Specifically, the first main switch is closed so that the output voltage of the first battery cell can be transmitted to the first common terminal through the first main switch. At the same time, the second main switch remains disconnected to avoid affecting the Nth battery cell. All switches in the switch group are disconnected to ensure that only the first main switch is affected during the detection process. The detection voltage between the first common terminal and the second common terminal is obtained to determine whether there are any sticky switches in the second switch group. Under normal circumstances, the first common terminal and the second common terminal should be in an open circuit state. If there is a sticky switch in the second switch group, there is a path between the first common terminal and the second common terminal. That is, if a voltage is detected between the first common terminal and the second common terminal, it is determined that there is a sticky switch in the second switch group.

[0110] Similarly, the second main switch is closed so that the output voltage of the Nth battery cell can be transmitted to the second common terminal through the second main switch. At the same time, the first main switch remains disconnected to avoid affecting the first battery cell. Disconnect all switches in the switch group to ensure that only the second main switch is affected during the detection process. Obtain the detection voltage between the first common terminal and the second common terminal to determine whether there are any sticky switches in the first switch group. Under normal circumstances, the first common terminal and the second common terminal should be in an open circuit state. If there are sticky switches in the first switch group, there is a path between the first common terminal and the second common terminal. That is, if a voltage is detected between the first common terminal and the second common terminal, it is determined that there are sticky switches in the first switch group.

[0111] If no stuck switches are found in the first switch group and the second switch group, it means that the switch group is in normal state. At this point, the detection process will enter the step of determining the switch adjustment strategy according to the detection requirements and adjusting the state of all switches multiple times to further detect the performance and state of the battery module.

[0112] Through the above steps, the test equipment can ensure that the operating status of all switch groups is normal, avoid measurement errors caused by sticking switches, and thus improve the accuracy and reliability of battery module detection.

[0113] For ease of understanding, the present application provides two specific embodiments. In one specific embodiment, if a cell module including N cell monomers does not include N+1 fuses, for example, when N is 4, the detection method of the cell module may include the following steps (e.g. Figure 3 shown):

[0114] Step 1: Determine whether the second switch group is stuck. The PC (Personal Computer) host computer controls the PLC (Programmable Logic Controller) (i.e., the processor described in the above embodiment) to control the first main switch to close through the LAN (Local Area Network) communication mode. The PC host computer reads the voltage between the first common terminal and the second common terminal measured by the multimeter through the LAN communication mode. The judgment criteria are as follows:

[0115] 1. If the measured voltage exceeds a reasonable upper threshold, then the switches in the second switch group are stuck; 2. If the measured voltage is within a reasonable threshold, then the switches in the second switch group are not stuck.

[0116] It should be understood that the 10k resistor connected to the first main switch is used to prevent the battery module from short-circuiting due to switch adhesion in the first switch group.

[0117] Step 2: Determine whether the first switch group is sticky. The PC host computer controls the PLC to close the second main switch and disconnect the first main switch through LAN communication. The PC host computer reads the voltage between the first common terminal and the second common terminal measured by the multimeter through LAN communication. The judgment criteria are as follows:

[0118] 1. If the measured voltage exceeds a reasonable upper threshold value, switch sticking exists in the first switch group; 2. If the measured voltage is within a reasonable threshold value, switch sticking does not exist in the first switch group.

[0119] The 10k resistor at the second main switch end is used to prevent the battery module from short-circuiting due to sticking of switches in the second switch group.

[0120] Step 3: The PC host computer controls the PLC through LAN communication to close the first main switch and the second main switch. At this time, the multimeter can measure the total voltage of the battery module. At the same time, the PC host computer obtains the preset total voltage range of the battery module from the MES for comparison. The judgment criteria are:

[0121] 1. If the total voltage is within the preset total voltage range, the test is passed; 2. If the total voltage is not within the preset total voltage range, the test is failed.

[0122] If it is bad, the reasons are as follows:

[0123] 1. There is a welding disconnection problem in the battery module (that is, there is a disconnection problem between at least two battery cells); 2. There is an abnormality in the battery cell itself;

[0124] Step 4: Control the PLC through LAN communication by the PC host computer to disconnect the first main switch and the second main switch, and close the A1 and B1 relays (that is, the first switch in the first switch group and the second switch in the second switch group). In this way, the multimeter is connected to the BT1 battery to measure its voltage BT1α. Similarly, A2 and B2, A3 and B3, A4 and B4 are closed respectively, and the voltages BT2α, BT3α, and BT4α of BT2, BT3, and BT4 can be further obtained. Note that in the process of closing A1 and B1 until A4 and B4 are closed, only one group can be closed at the same time. These voltages are compared with the preset single voltage range in the PC host computer and the production MES system. The judgment criteria are as follows:

[0125] 1. If the cell voltage of the battery cell collected during the test is within the preset cell voltage range, the test is qualified; 2. If the cell voltage of the battery cell collected during the test is not within the preset cell voltage range, the test is failed;

[0126] If it is bad, it may include the following reasons:

[0127] 1. There is an abnormality in the battery cell itself, such as the K value exceeds the standard; 2. The welding of the battery cell module is disconnected.

[0128] Step 5: Regardless of whether the test is qualified or any test item fails during the test, the PC host computer controls the PLC through LAN communication to disconnect all switches and all main switches, and uploads the test data to the MES system for later management and traceability.

[0129] In another specific embodiment, if a cell module including N cell monomers includes N+1 fuses, such as N is 4, the detection method of the cell module may include the following steps (such as Figure 4 shown):

[0130] Step 1: Determine whether the second switch group is stuck. The PC host computer controls the PLC to close the first main switch through LAN communication. The PC host computer reads the voltage between the first common terminal and the second common terminal measured by the multimeter through LAN communication. The judgment criteria are as follows:

[0131] 1. If the measured voltage exceeds a reasonable upper threshold, then the switches in the second switch group are stuck; 2. If the measured voltage is within a reasonable threshold, then the switches in the second switch group are not stuck.

[0132] It should be understood that the 10k resistor connected to the first main switch is used to prevent the battery module from short-circuiting due to switch adhesion in the first switch group.

[0133] Step 2: Determine whether the first switch group is sticky. The PC host computer controls the PLC to close the second main switch and disconnect the first main switch through LAN communication. The PC host computer reads the voltage between the first common terminal and the second common terminal measured by the multimeter through LAN communication. The judgment criteria are as follows:

[0134] 1. If the measured voltage exceeds a reasonable upper threshold value, switch sticking exists in the first switch group; 2. If the measured voltage is within a reasonable threshold value, switch sticking does not exist in the first switch group.

[0135] The 10k resistor at the second main switch end is used to prevent the battery module from short-circuiting due to sticking of switches in the second switch group.

[0136] Step 3: The PC host computer controls the PLC through LAN communication to close the first main switch and the second main switch. At this time, the multimeter can measure the total voltage of the battery module. At the same time, the PC host computer obtains the preset total voltage range of the battery module from the MES for comparison. The judgment criteria are:

[0137] 1. If the total voltage is within the preset total voltage range, the test is passed; 2. If the total voltage is not within the preset total voltage range, the test is failed.

[0138] If it is bad, the reasons are as follows:

[0139] 1. There is a welding disconnection problem in the battery module (that is, there is a disconnection problem between at least two battery cells); 2. There is an abnormality in the battery cell itself; 3. At least one of the battery module collection fuses F1 and F5 is blown (that is, the first fuse is disconnected, and / or the N+1th fuse is disconnected).

[0140] Step 4: Control the PLC through LAN communication by the PC host computer to disconnect the first main switch and the second main switch, and close the A1 and B1 relays (that is, the first switch in the first switch group and the second switch in the second switch group). In this way, the multimeter is connected to the BT1 battery to measure its voltage BT1α. Similarly, A2 and B2, A3 and B3, A4 and B4 are closed respectively, and the voltages BT2α, BT3α, and BT4α of BT2, BT3, and BT4 can be further obtained. Note that in the process of closing A1 and B1 until A4 and B4 are closed, only one group can be closed at the same time. These voltages are compared with the preset single voltage range in the PC host computer and the production MES system. The judgment criteria are as follows:

[0141] 1. If the cell voltage of the battery cell collected during the test is within the preset cell voltage range, the test is qualified; 2. If the cell voltage of the battery cell collected during the test is not within the preset cell voltage range, the test is failed;

[0142] If it is bad, it may include the following reasons:

[0143] 1. There is an abnormality in the battery cell itself, such as the K value exceeds the standard; 2. The battery cell module welding is disconnected; 3. At least one of the battery cell module collection fuses F2~F4 is disconnected. The specific fuse that is disconnected can be located based on which battery cell string has poor single cell voltage.

[0144] Step 5: Control the PLC through LAN communication by the PC host computer to close the first voltage divider switch C and the second voltage divider switch D, and then repeat the operation of step 4 to close A1 and B1, A2 and B2, A3 and B3, A4 and B4 respectively. Further, the voltages BT1β, BT2β, BT3β, and BT4β of BT1, BT2, BT3, and BT4 can be obtained respectively. Note that in the process of closing A1 and B1 until A4 and B4 are closed, only one group can be closed at the same time. Subtract these voltages from the voltage obtained in step 4 through the PC host computer to obtain |BT1α-BT1β|, |BT2α-BT2β|, |BT3α-BT3β|, and |BT4α-BT4β|. Determine the obtained voltage difference. The determination criteria are as follows:

[0145] 1. If the pressure difference is within the reasonable threshold range, the test is qualified; 2. If the pressure difference is not within the reasonable threshold range, the test is unsatisfactory;

[0146] If it is bad, there may be the following reasons:

[0147] 1. If at least one of the fuses F1~F5 in the cell module is broken, the cell with bad voltage difference can be used to determine which fuse is broken. 2. If the cell module is poorly welded, the cell with bad voltage difference can be used to determine which cell has poor welding.

[0148] Step 6: Regardless of whether the test is qualified or any test item fails during the test, the PC host computer controls the PLC through LAN communication to disconnect all switches and all main switches, and uploads the test data to the MES system for later management and traceability.

[0149] In summary, the solution provided by the present invention can comprehensively detect the conditions of cold welding, broken wires, and false fuses of the battery module. It can not only detect whether the battery collection is broken, but also accurately detect the conditions of cold welding and false breaking, thereby improving the quality and safety of the battery module. In addition, the solution provided by the present invention can realize fully automatic interception and control through a processor (such as PLC), which greatly improves production efficiency and reduces production costs; compared with the existing manual operation method, it not only reduces the consumption of human resources, but also avoids human errors and improves the accuracy of the detection results. The present invention can feed back the detection results to the MES system for control, realize real-time monitoring and management of the production process, and is conducive to improving production efficiency and product quality. In summary, the present invention can effectively reduce rework and scrapping caused by quality problems of battery modules, optimize the production process, and improve production efficiency.

[0150] On the other hand, the present application provides a battery cell module detection device, comprising:

[0151] Memory for storing computer programs;

[0152] The processor is used to implement the steps of the above-mentioned battery module detection method when executing a computer program. The processor can be a PLC or a processor with other specific control functions. Please refer to the above-mentioned embodiment for the introduction of the battery module detection device, and this application will not repeat it here.

[0153] On the other hand, the present application provides a computer storage medium, in which a computer program is stored, and when the computer program is executed by a processor, the steps of the above-mentioned method for detecting a battery cell module are implemented. For the introduction of the computer storage medium, please refer to the above-mentioned embodiment, and the present application will not repeat it here.

[0154] On the other hand, the present application provides a test device, including a power supply 11, a processor 12, and two switch groups;

[0155] The power supply 11 is connected to the power supply 11 terminal of the processor 12 and the power supply 11 terminals of the two switch groups respectively;

[0156] Each switch group includes N switches, the first end of the i-th switch in the first switch group 13 is connected to the first output end of the i-th battery cell in the battery module, the first end of the i-th switch in the second switch group 14 is connected to the second output end of the i-th battery cell, the second ends of the N switches in the first switch group 13 are connected and serve as a first common end, the second ends of the N switches in the second switch group 14 are connected and serve as a second common end, the battery module includes N battery cells connected in series, 1≤i≤N, N>1, and i and N are both integers;

[0157] The processor 12 is used to implement the steps of the above-mentioned method for detecting the battery cell module when executing the computer program.

[0158] The overall diagram of the test equipment can be referred to Figure 5 , wherein the first switch group 13 and the second switch group 14 can be implemented by two relays,, the processor 12 can be implemented by PLC, the power supply 11 provides basic power supply for PLC and relays, and the position of each module can refer to Figure 5 , Figure 5 As one of the implementation methods, Figure 4 In the system, each module is encapsulated in a box, the processor 12 and the power supply 11 are arranged in sequence on one side of the box, and the two switch groups are arranged in sequence on the other side of the box. Placing the processor 12 and the power supply 11 on one side of the box can reduce the length of the power supply 11 line and reduce the impact of the power supply 11 interference on the processor 12 signal, thereby improving the stability and response speed of the system; the two switch groups are arranged relatively independently on the other side of the box, making the wiring of the switch and each battery cell more convenient, the line more tidy, and easy to maintain and troubleshoot; at the same time, this layout also provides space for thermal management, avoiding heat accumulation caused by the aggregation of multiple modules, thereby improving the overall reliability of the equipment. In addition, the clear partition design of the module makes the entire device more neat in terms of vision and function, and is also convenient for future expansion and upgrades, such as adding more switch groups or other devices without having to reconstruct the entire system.

[0159] The circuit connection diagram of each part of the test equipment can be referred to Figure 2 , Figure 2 In the example, taking N as 4, the battery cells are represented by BT1-BT4. If the battery cell module also includes N+1 fuses, Figure 2 In the figure, the fuses are denoted by F1-F5, the N switches in the first switch group 13 are denoted by A1-A4, and the N switches in the second switch group 14 are denoted by B1-B4.

[0160] In a preferred embodiment, it also includes a first main switch and a second main switch; the first end of the first main switch is connected to the first output end of the first battery cell, the second end of the first main switch is connected to the first common end, the second end of the second main switch is connected to the second output end of the Nth battery cell, and the second end of the second main switch is connected to the second common end.

[0161] In a preferred embodiment, it also includes a first current limiting component and a second current limiting component; the first current limiting component is arranged between the second end of the first main switch and the first common end, and the second current limiting component is arranged between the second end of the second main switch and the second common end.

[0162] Figure 2In the embodiment, the first current limiting component is a 10k resistor connected to the first main switch, and the second current limiting component is a 10k resistor connected to the second main switch.

[0163] In a preferred embodiment, it further includes a voltage dividing passage; the voltage dividing passage is arranged between the first common terminal and the second common terminal. Figure 2 In the figure, it is the path formed by C, 5Ω resistor and D.

[0164] In a preferred embodiment, the voltage dividing path includes a first voltage dividing switch, a second voltage dividing switch and a first resistor, the first resistor is arranged between the first end of the first voltage dividing switch and the first end of the second voltage dividing switch, the second end of the first voltage dividing switch is connected to the first common end, and the second end of the second voltage dividing switch is connected to the second common end. Figure 2 In the figure, the first resistor may be a 5Ω resistor as shown, the first voltage divider switch may be C, the second voltage divider switch may be D, and the specific implementation of the voltage divider switches may be relay contacts.

[0165] For other descriptions of the testing device, please refer to the above embodiments, and this application will not go into details here.

[0166] It should also be noted that, in this specification, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "comprises", "comprising" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the statement "comprising a ..." does not exclude the presence of other identical elements in the process, method, article or device including the element.

[0167] 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 apparent to those skilled in the art, and the general principles defined herein may 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 rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for detecting a battery cell module, characterized in that: A processor applied to a test device, wherein the test device further comprises two switch groups, each of which comprises N switches, the battery module comprises N battery cells connected in series, the first end of the i-th switch in the first switch group is connected to the first output end of the i-th battery cell, the first end of the i-th switch in the second switch group is connected to the second output end of the i-th battery cell, the second ends of the N switches in the first switch group are connected and serve as a first common end, the second ends of the N switches in the second switch group are connected and serve as a second common end, 1≤i≤N, N>1, and i and N are both integers; The detection method of the battery cell module comprises: Determine a switch adjustment strategy according to the detection requirements, and adjust the states of all the switches multiple times according to the switch adjustment strategy; After each adjustment of the state of the switch is completed, a detection voltage between the first common terminal and the second common terminal is obtained and used as the output voltage of one of the battery cells corresponding to the current switch state or the output voltage of M battery cells connected in series, 1<M≤N, and M is an integer; The detection result of the battery cell module is determined according to the detection voltage obtained by adjusting the state of the switch for multiple times.

2. The method for detecting a battery cell module according to claim 1, characterized in that: Adjusting the states of all the switches multiple times according to the switch adjustment strategy includes: Controlling the first switch in the first switch group to be closed and the Nth switch in the second switch group to be closed, and all switches except the first switch in the first switch group and the Nth switch in the second switch group to be opened; Controlling the i-th switch in the first switch group and the i-th switch in the second switch group to be closed, and all switches except the two i-th switches to be opened, wherein i increases gradually from 1 to N in chronological order; After each adjustment of the state of the switch is completed, the detection voltage between the first common terminal and the second common terminal is obtained and used as the output voltage of one of the battery cells corresponding to the current switch state or the output voltage of M battery cells connected in series, including: After controlling the first switch in the first switch group to close and the Nth switch in the second switch group to close, obtaining the detection voltage between the first common terminal and the second common terminal and using it as the total voltage after the N battery cells are connected in series; After controlling the i-th switch in the first switch group and the i-th switch in the second switch group to be closed, obtaining a detection voltage between the first common terminal and the second common terminal and using the detection voltage as a cell voltage of the i-th battery cell; Determining the detection result of the battery cell module according to the detection voltage obtained by adjusting the state of the switch for multiple times includes: The detection result of the battery cell module is determined according to the total voltage and the cell voltage of each of the battery cell cells.

3. The method for detecting a battery cell module according to claim 2, wherein: Determining the detection result of the battery cell module according to the total voltage and the cell voltage of each of the battery cell cells includes: Comparing the total voltage with a preset total voltage range, and determining whether there is an abnormality in the battery cell module according to the comparison result of the total voltage; If an abnormality exists in the battery cell module, the cell voltage of each of the battery cell monomers is compared with a preset cell voltage range, and the abnormal position of the battery cell module is determined according to the comparison result of the cell voltage of each of the battery cell monomers.

4. The method for detecting a battery cell module according to claim 3, characterized in that: Determining whether there is an abnormality in the battery cell module according to the comparison result of the total voltage includes: If the total voltage is continuously less than the minimum value in the preset total voltage range within the preset time, it is determined that there is a disconnection between at least two of the battery cells, and / or that there is at least one abnormal battery cell; If the total voltage is not continuously less than the minimum value in the preset total voltage range within the preset time, and the total voltage fluctuates, then a first difference between the maximum voltage value and the minimum voltage value during the total voltage fluctuation process is calculated, and it is determined whether the first difference is within the preset fluctuation voltage range; If the first difference is not within the preset fluctuation voltage range, it is determined that a cold solder joint exists between at least two of the battery cell monomers.

5. The method for detecting a battery cell module according to claim 3, characterized in that: The battery module further includes N+1 fuses, the first end of the i-th fuse is connected to the first output end of the i-th battery cell, the first end of the N+1-th fuse is connected to the second output end of the N-th battery cell, the second end of the i-th fuse is connected to the first end of the i-th switch in the first switch group, and the i-th switch in the second switch group is connected to the second end of the i+1-th fuse; Determining whether there is an abnormality in the battery cell module according to the comparison result of the total voltage includes: If the total voltage is continuously less than the minimum value in the preset total voltage range within the preset time, it is determined that there is a disconnection between at least two of the battery cells, and / or there is at least one abnormal battery cell, and / or the first fuse is disconnected, and / or the N+1th fuse is disconnected; If the total voltage is not continuously less than the minimum value in the preset total voltage range within the preset time, and the total voltage fluctuates, then a first difference between the maximum voltage value and the minimum voltage value during the total voltage fluctuation process is calculated, and it is determined whether the first difference is within the preset fluctuation voltage range; If the first difference is not within the preset fluctuation voltage range, it is determined that there is a cold solder joint between at least two of the battery cells, and / or the first fuse is cold-blown, and / or the N+1th fuse is cold-blown.

6. The method for detecting a battery cell module according to claim 5, characterized in that: The testing device further includes a voltage dividing path provided between the first common terminal and the second common terminal; when i=N, after obtaining the detection voltage between the first common terminal and the second common terminal and using it as the cell voltage of the i-th battery cell, the testing device further includes: Control all switches in the switch group to be turned off, control the voltage dividing path to be turned on, and again control the i-th switch in the first switch group and the i-th switch in the second switch group to be turned on, and all switches except the two i-th switches are turned off, and i gradually increases from 1 to N in chronological order; After controlling the i-th switch in the first switch group and the i-th switch in the second switch group to be closed simultaneously, obtaining the i-th divided voltage value on the divided voltage path; According to the i-th voltage division value and the i-th cell voltage, it is determined whether the i-th battery cell has a cold solder joint, and / or whether the i-th fuse and the i+1-th fuse have a cold blow.

7. The method for detecting a battery cell module according to claim 6, characterized in that: The voltage dividing path includes a first voltage dividing switch, a second voltage dividing switch and a first resistor, wherein the first resistor is arranged between a first end of the first voltage dividing switch and a first end of the second voltage dividing switch, a second end of the first voltage dividing switch is connected to the first common end, and a second end of the second voltage dividing switch is connected to the second common end; Controlling the conduction of the voltage dividing path includes: The first voltage-dividing switch and the second voltage-dividing switch are controlled to be closed.

8. The method for detecting a battery cell module according to any one of claims 1 to 7, characterized in that: The test device further includes a first main switch and a second main switch, wherein a first end of the first main switch is connected to a first output end of a first battery cell, a second end of the first main switch is connected to the first common end, a first end of the second main switch is connected to a second output end of an Nth battery cell, and a second end of the second main switch is connected to the second common end; Determining a switch adjustment strategy according to the detection requirement, and before adjusting the states of all the switches multiple times according to the switch adjustment strategy, the detection method of the battery cell module further includes: Controlling the first main switch to close, the second main switch to open, and all switches in the switch group to open, and obtaining a detection voltage between the first common terminal and the second common terminal to determine whether there is a stuck switch in the second switch group; Controlling the second main switch to close, the first main switch to open, and all switches in the switch group to open, and obtaining a detection voltage between the first common terminal and the second common terminal to determine whether there is a sticky switch in the first switch group; If there are no stuck switches in the first switch group and the second switch group, the process proceeds to the step of determining a switch adjustment strategy according to a detection requirement, and adjusting the states of all the switches multiple times according to the switch adjustment strategy.

9. A battery module detection device, characterized in that: include: Memory for storing computer programs; A processor, used to implement the steps of the method for detecting a battery cell module as described in any one of claims 1 to 8 when executing the computer program.

10. A testing device, characterized in that: Includes power supply, processor and two switch groups; The power supply is respectively connected to the power supply terminal of the processor and the power supply terminals of the two switch groups; Each of the switch groups includes N switches, the first end of the i-th switch in the first switch group is connected to the first output end of the i-th battery cell in the battery cell module, the first end of the i-th switch in the second switch group is connected to the second output end of the i-th battery cell, the second ends of the N switches in the first switch group are connected and serve as a first common end, the second ends of the N switches in the second switch group are connected and serve as a second common end, the battery cell module includes N battery cells connected in series, 1≤i≤N, N>1, and i and N are both integers; The processor is used to implement the steps of the battery cell module detection method as described in any one of claims 1 to 8 when executing a computer program.

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