Detection device of battery cell insulation detection probe and battery cell insulation detection device
By constructing a cell insulation testing device with odd and even detection branches and auxiliary probe branches, the problem of detection deviation caused by poor probe contact was solved, and the accuracy and efficiency of cell insulation testing were improved.
Patent Information
- Application Number
- CN202422984625.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-04
- Publication Date
- 2025-11-28
- Estimated Expiration
- 2034-12-04
AI Technical Summary
In existing technologies, poor contact between the probe and the electrode post during insulation testing between battery cells leads to deviations in the test results, making it difficult to accurately determine the insulation status.
Design a detection device for cell insulation testing probes. Construct a detection loop by using odd and even number detection branches and auxiliary probe branches. Use detection devices to check whether each loop is conductive, determine the good contact of the probes, and connect them in parallel to a bus for insulation performance testing.
This effectively avoids the risk of poor contact between the probe and the cell terminal, improves the accuracy and efficiency of testing, and ensures the reliability of insulation test results.
Smart Images
Figure CN223611694U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model belongs to the electric core insulation detection field, concretely relates to a detection device and electric core insulation detection device of electric core insulation detection probe. BACKGROUND
[0002] At present, electric vehicles using lithium ion battery systems are increasing, and while the production of lithium ion battery systems is rapidly increasing, seeking high-efficiency and reliable performance detection technology is also the direction of efforts of battery system manufacturers.
[0003] During the production of electric vehicle battery packs, module processing is first required, specifically, multiple electric cores are pasted together by double-sided tape, and then side insulation plates, steel belts and other accessories are installed to form a module. Finally, multiple modules are hoisted into a box, and then wire harnesses, CSC accessories and covers are installed to become a complete battery pack.
[0004] The insulation performance between the electric cores included in the module is related to whether the vehicle can drive normally, so the insulation performance detection between the electric cores of the module is crucial. After the module processing is completed, the insulation performance between the electric cores of the module needs to be detected. For enterprises, quickly and effectively detecting the insulation performance between the electric cores of the module can meet the performance detection requirements, ensure the detection quality, and meet the production line production efficiency.
[0005] A simplified module schematic diagram is shown in Figure 1 The double-sided tape (b in Figure 1 ) pastes multiple electric cores (a in Figure 1 ) together to form a module. Insulation detection specifically detects the insulation performance between the electric core housings before the next process.
[0006] However, the current domestic power system manufacturers usually measure the insulation resistance of adjacent electric cores to determine their insulation. The positive pole of the electric core (c in Figure 1 ) is connected to the electric core housing by 50Ω, so the specific means is to press the detection probe on the electric core pole for insulation detection. During the insulation detection process, it is necessary to ensure that all probes are in complete contact with the electric core pole. However, in actual operation, the probe spring may be aged, the probe may be insensitive, or there may be mechanical failures, which may cause poor contact between the probe and the pole, and thus result in large deviations in the detection results, making it difficult to accurately determine the insulation state between the electric cores. INVENTION CONTENTS
[0007] The utility model discloses a kind of detection device of battery cell insulation detection probe, and battery cell insulation detection device, for solving the problem that in prior art, due to probe and pole post contact badly, resulting in detection result appears larger deviation, make it difficult to accurately judge the insulation state between battery cell.
[0008] In order to achieve the above object, the utility model provides a kind of new detection device of battery cell insulation detection probe, the device includes the detection branch of bus connection for being connected with the parallel insertion of the positive pole post of each battery cell insulation detection probe and the detection branch of bus connection for being connected with the parallel insertion of the positive pole post of each battery cell auxiliary probe;
[0009] The detection branch includes odd detection branch and even detection branch;
[0010] The odd detection branch is the branch of bus connection for being connected with the parallel insertion of the positive pole post of odd battery cell insulation detection probe;The even detection branch is the branch of bus connection for being connected with the parallel insertion of the positive pole post of even battery cell insulation detection probe;
[0011] The auxiliary probe branch includes odd auxiliary probe branch and even auxiliary probe branch;
[0012] The odd auxiliary probe branch is the branch for being connected with the auxiliary probe inserted on the positive pole post of odd battery cell;The even auxiliary probe branch is the branch for being connected with the auxiliary probe inserted on the positive pole post of even battery cell.
[0013] The beneficial effects of the technical scheme of the detection device of the battery cell insulation detection probe include: the device connects the bus to which the detection probe inserted on the odd positive pole of the battery cell is connected in parallel with the odd detection branch, and connects the bus to which the detection probe inserted on the even positive pole of the battery cell is connected in parallel with the even detection branch; and connects the auxiliary probe inserted on the positive pole of each battery cell with the corresponding auxiliary probe branch; and constructs the detection loop of "the bus to which the detection probe inserted on the odd positive pole of the battery cell is connected-odd detection branch-detection device-odd auxiliary probe branch" (that is, the detection loop of the odd battery cell, the number of the detection loop is equal to the number of the odd battery cell and one-to-one correspondence) and the detection loop of "the bus to which the detection probe inserted on the even positive pole of the battery cell is connected-even detection branch-detection device-even auxiliary probe branch" (that is, the detection loop of the even battery cell, the number of the detection loop is equal to the number of the even battery cell and one-to-one correspondence). The detection device is used for detecting whether each odd battery cell detection loop is conductive, and whether the detection probe inserted on the positive pole of each odd battery cell is in good contact is judged according to whether it is conductive; similarly, whether the detection probe inserted on the positive pole of each even battery cell is in good contact is judged. If all the detection loops of the battery cells are conductive, it is determined that all the detection probes are in good contact with the battery cell poles. At this time, the insulation performance between the odd battery cell and the even battery cell is detected, which can effectively avoid the risk of poor contact between the detection probe and the battery cell pole, and further make the detection result of the insulation detection more accurate and improve the detection efficiency.
[0014] Further, the detection device is a multimeter with a built-in power supply.
[0015] Further, the probe circuit board is further provided, and the connection node of one side of the positive pole and the negative pole of the detection device of the auxiliary probe branch and the connection node of the other side of the positive pole and the negative pole of the detection device of the odd detection branch and the even detection branch are arranged on the probe circuit board.
[0016] Further, the connection node of one side of the positive pole and the negative pole of the detection device of the auxiliary probe branch corresponding to the positive pole of the odd battery cell and the connection node of the other side of the positive pole and the negative pole of the detection device of the odd detection branch are arranged on the same side area of the probe circuit board; and the connection node of one side of the positive pole and the negative pole of the detection device of the auxiliary probe branch corresponding to the positive pole of the even battery cell and the connection node of the other side of the positive pole and the negative pole of the detection device of the even detection branch are arranged on the same side area of the probe circuit board.
[0017] The utility model discloses still provide a kind of electric core insulation detection device, the device includes the detection device of electric core insulation detection probe, the insulation detection probe for being inserted with the positive pole of each electric core, the auxiliary probe for being inserted with the positive pole of each electric core, the insulation detection probe inserted with the positive pole of odd electric core and the bus of parallel connection of auxiliary probe inserted with the positive pole of even electric core;The detection device of electric core insulation detection probe includes one side and the bus connection of the bus of parallel connection of the insulation detection probe inserted with the positive pole of odd electric core, one side and the bus connection of the bus of parallel connection of the insulation detection probe inserted with the positive pole of even electric core and respectively for through one side auxiliary probe and each electric core positive pole one-to-one corresponding connection each auxiliary probe branch;
[0018] The other side of auxiliary probe branch is used for connecting one of positive and negative poles of detection device, and the other side of odd detection branch and even detection branch is used for connecting the other pole of detection device, to form a series loop comprising detection device, auxiliary probe branch for connecting detection device, positive pole connected by one side of auxiliary probe branch, insulation detection probe inserted with the positive pole and bus and bus connection of odd detection branch or even detection branch of parallel connection of the bus of parallel connection.
[0019] The beneficial effects of the technical scheme of the electric core insulation detection device of the utility model above include: the device is mainly composed of two parts, one part is the detection device of electric core insulation detection probe, and the other part is electric core insulation detection probe and the bus of parallel connection of the bus of parallel connection of electric core insulation detection probe connected with the detection device of electric core insulation detection probe and auxiliary probe inserted with the positive pole of each electric core;The device is actually combined with the detection of electric core insulation detection probe and electric core insulation detection, detects and judges whether detection probe is in good contact with electric core pole before insulation detection, that is, according to whether the loop of "the bus of parallel connection of detection probe inserted with each electric core corresponding to each detection branch-detection device-each auxiliary probe branch" is conducted, judges whether detection probe is in good contact with electric core pole. Effectively avoid the risk that detection probe is not in good contact with electric core pole, and then make the detection result of insulation detection more accurate, and improve detection efficiency.
[0020] Further, the detection device is a multimeter with built-in power supply.
[0021] Further, it further includes probe circuit board, and the connecting node of one side of auxiliary probe branch for connecting one of positive and negative poles of detection device and the connecting node of one side of odd detection branch and even detection branch for connecting the other pole of positive and negative poles of detection device are arranged on the probe circuit board.
[0022] Furthermore, the connection node on one side of the auxiliary probe branch corresponding to the positive terminal of the odd-numbered battery cells, which is used to connect to one of the positive and negative terminals of the detection device, and the connection node on one side of the odd-numbered detection branch, which is used to connect to the other of the positive and negative terminals of the detection device, are both located on the same side of the probe circuit board; the connection node on one side of the auxiliary probe branch corresponding to the positive terminal of the even-numbered battery cells, which is used to connect to one of the positive and negative terminals of the detection device, and the connection node on one side of the odd-numbered detection branch, which is used to connect to the other of the positive and negative terminals of the detection device, are both located on the same side of the probe circuit board. Attached Figure Description
[0023] Figure 1 This is a simplified example diagram of a battery cell module in the background art of this utility model;
[0024] Figure 2 This is an example diagram of a probe circuit board with odd / even cell detection lines and auxiliary probe lines for each cell, as shown in the embodiment of the detection device for cell insulation detection probes of this utility model.
[0025] Figure 3 This is an example diagram showing the connection of probes on the positive terminals of each battery cell in an embodiment of the battery cell insulation testing probe of this utility model.
[0026] Wherein, a represents a single battery cell; b represents double-sided tape bonded between two battery cells; c represents the positive terminal of a battery cell; 1 represents an auxiliary probe branch connected to the odd-numbered detection branch; 1' represents a connection node for connecting one side of the positive and negative terminals of a multimeter; 2 represents the odd-numbered detection branch; 2' represents the connection node for connecting the other side of the positive and negative terminals of a detection device in the odd-numbered detection branch; 3 represents the even-numbered detection branch; 3' represents the connection node for connecting the other side of the positive and negative terminals of a detection device in the even-numbered detection branch; 4 represents an auxiliary probe branch connected to the even-numbered detection branch; 4' represents a connection node for connecting one side of the positive and negative terminals of a multimeter; 5 represents the parallel bus for the insulation detection probes inserted into the positive terminal of the odd-numbered battery cells; 6 represents the parallel bus for the insulation detection probes inserted into the positive terminal of the even-numbered battery cells; and 7 represents the insulation detection probes inserted into the positive terminal of each battery cell. Detailed Implementation
[0027] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments.
[0028] Example of a testing device for cell insulation testing probes
[0029] This embodiment provides a technical solution for a detection device for cell insulation detection probes. The device detects whether the circuit formed by the insulation detection probes inserted on the positive terminals of odd / even cells and their corresponding auxiliary probes is conductive, and determines whether the detection probes inserted on the positive terminals of each cell are in good contact. This effectively avoids the risk of inaccurate detection due to poor contact between the insulation detection probes and the positive terminals of the cells, and provides a good detection foundation for subsequent cell insulation detection.
[0030] The detection device for the cell insulation detection probe provided in this embodiment specifically includes an odd-numbered detection branch connected in parallel to a bus for the insulation detection probes inserted into the positive terminal of the odd-numbered cells on one side, an even-numbered detection branch connected in parallel to the insulation detection probes inserted into the positive terminal of the even-numbered cells on one side, and auxiliary probe branches for connecting to the positive terminal of each cell one-to-one through the auxiliary probes on one side.
[0031] The other side of the auxiliary probe branch is used to connect to one of the positive and negative poles of the detection device (in this embodiment, the detection device is a multimeter with a built-in power supply; in other embodiments, it can be other detection meters, detection branches, or detection instruments, as long as they can be used to detect the continuity of the circuit). The other side of the odd-numbered detection branches and even-numbered detection branches is used to connect to the other pole of the detection device, so as to form a series circuit including the detection device, the auxiliary probe branch for connecting the detection device, the positive pole connected to one side of the auxiliary probe branch, the insulating detection probe inserted on the positive pole and its parallel bus, and the series circuit of the odd-numbered detection branches or even-numbered detection branches connected to the bus.
[0032] Specifically, such as Figure 2 As shown, the detection device for the cell insulation detection probe mainly includes three types of detection branches: auxiliary probe branches, odd-numbered detection branches (i.e.,... Figure 2 The detection branch located on the left (2) and the even-numbered detection branch (i.e. Figure 2 The detection branch 3 is located on the right side; detection branch 2 is used to connect in parallel with the insulation detection probes inserted on the positive terminal of the odd-numbered cells to the bus; detection branch 3 is used to connect in parallel with the insulation detection probes inserted on the positive terminal of the even-numbered cells to the bus. Figure 2 Branch 1 in the diagram represents one of the auxiliary probe branches; taking auxiliary probe branch 1 as an example, this branch is connected to... Figure 3 The auxiliary probe 7 on the positive terminal of the battery cell is connected; similarly, one side of each auxiliary probe branch is connected to the positive terminal of the battery cell through its corresponding auxiliary probe.
[0033] Reference Figure 2The probe circuit board is also part of the detection device of the cell insulation detection probe, wherein the connection nodes of one side of the auxiliary probe branch for connecting one of the positive and negative poles of the detection device and the connection nodes of one side of the odd and even detection branches for connecting the other of the positive and negative poles of the detection device are arranged on the probe circuit board.
[0034] In addition, in the embodiment, the probe circuit board is arranged on the probe circuit board. Figure 2 The connection nodes of one side of the auxiliary probe branch for connecting one of the positive and negative poles of the detection device and the connection nodes of one side of the odd and even detection branches for connecting the other of the positive and negative poles of the detection device are arranged on the same side region of the probe circuit board.
[0035] Specifically, the probe circuit board is provided with two types of connection nodes, one type of connection node is a connection node for connecting one of the positive and negative poles of the multimeter (i.e. node 1' and node 4'), and the other type of connection node is a connection node for connecting the other of the positive and negative poles of the multimeter (i.e. node 2' and node 3') of the odd and even detection branches (i.e. detection branch 2 and detection branch 3).
[0036] The node 1' is a connection node of one side of the auxiliary probe branch for connecting one of the positive and negative poles of the detection device corresponding to the positive pole of the odd cell, and the node 2' is a connection node of one side of the odd detection branch for connecting the other of the positive and negative poles of the detection device. The node 1' and the node 2' are arranged on the same side region (i.e. the left side of the probe circuit board in Figure 2
[0037] The node 4' is a connection node of one side of the auxiliary probe branch for connecting one of the positive and negative poles of the detection device corresponding to the positive pole of the even cell, and the node 3' is a connection node of one side of the even detection branch for connecting the other of the positive and negative poles of the detection device. The node 4' and the node 3' are arranged on the same side region (i.e. the right side of the probe circuit board in Figure 2 This arrangement of the connection nodes on both sides of the probe circuit board, i.e. the odd cell detection probe and the even cell detection probe are distinguished in spatial position, can effectively improve the detection efficiency, maintain physical symmetry, and meet the demand for aesthetics.
[0038] In the detection, the other side of the auxiliary probe branch to be detected (i.e. auxiliary probe branch 1, one end of which is connected with auxiliary probe 7, and the other end is connected at node 1') is connected with the built-in power supply of the multimeter (i.e. the detection device), and can be connected with the positive or negative pole of the multimeter; taking the case that the other side of the auxiliary probe branch to be detected is connected with the positive pole of the detection device as an example, the other sides of the odd detection branch and the even detection branch (i.e. detection branch 2 located on the left side in the figure) are connected with the negative pole of the multimeter, i.e. when detecting the positive pole of an electric core, the auxiliary probe branch connected with the electric core and the corresponding odd (or even) detection circuit are connected through the multimeter to form a series circuit comprising the multimeter, the auxiliary probe branch connected with the multimeter, the positive pole connected with one side of the auxiliary probe branch, the insulation detection probe inserted into the positive pole, and the bus (i.e. bus 5 or bus 6 shown in Figure 3 FIG. 1; in other embodiments, bus 5 can use the same line as detection branch 2, and bus 6 can use the same line as detection branch 3) and the odd detection branch or the even detection branch connected with the bus. The above detection device (i.e. the multimeter) is used to detect whether the series circuit is conductive. The detection method is as follows: first, the circuit mainly comprising the odd detection branch and the corresponding auxiliary probe branch is detected in sequence to determine whether it is conductive; if there is a non-conductive circuit, the detection is stopped, and it is concluded that the probe corresponding to the non-conductive circuit is in poor contact; similarly, the circuit comprising the even detection branch and the corresponding auxiliary probe branch is detected, i.e. whether the above circuit is conductive is detected in sequence. If each of the odd detection branch and the even detection branch is conductive, each insulation detection probe is normally connected with the positive pole of the electric core.
[0039] Embodiment of the electric core insulation detection device
[0040] The embodiment provides a technical scheme of an electric core insulation detection device. The device detects whether the detection probe is in good contact with the electric core pole, and then detects the insulation performance of the electric core if the detection result is that the detection probe is in good contact. Through the combination of the above two detections, the electric core insulation detection is more accurate and efficient.
[0041] The electric core insulation detection device comprises a detection device of an electric core insulation detection probe, an insulation detection probe inserted into the positive pole of each electric core, an auxiliary probe inserted into the positive pole of each electric core, a bus to which the insulation detection probe inserted into the positive pole of each odd electric core is connected in parallel, and a bus to which the insulation detection probe inserted into the positive pole of each even electric core is connected in parallel.
[0042] The detection device of the cell insulation detection probe comprises an odd number detection branch connected in parallel to the bus and used for connecting the insulation detection probe inserted into the positive pole of the odd number cell, an even number detection branch connected in parallel to the bus and used for connecting the insulation detection probe inserted into the positive pole of the even number cell, and a plurality of auxiliary probe branches respectively used for connecting the positive poles of the cells through the auxiliary probes.
[0043] The other side of the auxiliary probe branch is used for connecting one of the positive pole and the negative pole of the detection device, and the other side of the odd number detection branch and the even number detection branch is used for connecting the other pole of the detection device, so as to form a series loop comprising the detection device, the auxiliary probe branch used for connecting the detection device, the positive pole connected to the one side of the auxiliary probe branch, the insulation detection probe inserted into the positive pole, the bus connected in parallel to the insulation detection probe, and the odd number detection branch or the even number detection branch connected to the bus.
[0044] Specifically, the cell insulation detection device mainly comprises the detection device of the cell insulation detection probe, the insulation detection probe inserted into the positive pole of each cell, the auxiliary probe inserted into the positive pole of each cell, the bus connected in parallel to the insulation detection probe inserted into the positive pole of the odd number cell, and the bus connected in parallel to the insulation detection probe inserted into the positive pole of the even number cell.
[0045] Referring to the detection device of the cell insulation detection probe in the embodiment of the cell insulation detection device Figure 3 As shown in the figure, the insulation detection probe inserted into the positive pole of the first cell and the insulation detection probe inserted into the positive pole of the third cell are connected in parallel to the bus 5, and the insulation detection probe inserted into the positive pole of the second cell and the insulation detection probe inserted into the positive pole of the fourth cell are connected in parallel to the bus 6.
[0046] The other side of the auxiliary probe branch is used for connecting one of the positive pole and the negative pole of the detection device (the detection device is a multimeter with an internal power supply), and the other side of the odd number detection branch and the even number detection branch is used for connecting the other pole of the detection device, so as to form a series loop comprising the detection device, the auxiliary probe branch used for connecting the detection device, the positive pole connected to the one side of the auxiliary probe branch, the insulation detection probe inserted into the positive pole, the bus connected in parallel to the insulation detection probe, and the odd number detection branch or the even number detection branch connected to the bus.
[0047] Specifically, since the specific structure and principle of the detection device of the cell insulation detection probe contained in the cell insulation detection device have been described in detail in the above-mentioned embodiment of the cell insulation detection device, they will not be described here.
[0048] It should be understood that the above specific embodiments of the present application are only used for illustrative or explanatory purposes of the principles of the present application, and do not constitute a limitation on the present application.
Claims
1. A detection device of an electric cell insulation detection probe, characterized by, The odd number detection branch and the even number detection branch are connected to the bus in parallel through the insulation detection probes inserted into the positive electrode poles of the odd number and even number battery cells respectively. The other side of the auxiliary probe branch is used for connecting one of the positive and negative poles of the detection device, and the other side of the odd number detection branch and the even number detection branch is used for connecting the other pole of the detection device, so as to form a series loop comprising the detection device, the auxiliary probe branch for connecting the detection device, the positive electrode pole connected to the one side of the auxiliary probe branch, the insulation detection probe inserted into the positive electrode pole, the bus connected in parallel with the insulation detection probe, and the odd number detection branch or the even number detection branch connected to the bus.
2. The detection device of the electric chip insulation detection probe according to claim 1, characterized in that, The detection device is a multimeter with built-in power supply.
3. The detection device of the electric chip insulation detection probe according to claim 1 or 2, characterized in that, The probe circuit board is further provided, and the connection nodes on the one side of the auxiliary probe branch for connecting one of the positive and negative poles of the detection device and the connection nodes on the one side of the odd number detection branch and the even number detection branch for connecting the other pole of the detection device are arranged on the probe circuit board.
4. The detection device of the electric chip insulation detection probe according to claim 3, characterized in that, The connection nodes on the one side of the auxiliary probe branch for connecting one of the positive and negative poles of the detection device corresponding to the positive electrode poles of the odd number battery cells and the connection nodes on the one side of the odd number detection branch for connecting the other pole of the detection device are arranged in the same side region on the probe circuit board, and the connection nodes on the one side of the auxiliary probe branch for connecting one of the positive and negative poles of the detection device corresponding to the positive electrode poles of the even number battery cells and the connection nodes on the one side of the even number detection branch for connecting the other pole of the detection device are arranged in the same side region on the probe circuit board.
5. An electric cell insulation detection device, characterized by, The detection device of the battery cell insulation detection probe, the insulation detection probe inserted into the positive electrode pole of each battery cell, the auxiliary probe inserted into the positive electrode pole of each battery cell, the bus connected in parallel with the insulation detection probe inserted into the positive electrode pole of the odd number battery cell, and the bus connected in parallel with the insulation detection probe inserted into the positive electrode pole of the even number battery cell; the detection device of the battery cell insulation detection probe comprises an odd number detection branch connected to the bus in parallel with the insulation detection probe inserted into the positive electrode pole of the odd number battery cell on one side, an even number detection branch connected to the bus in parallel with the insulation detection probe inserted into the positive electrode pole of the even number battery cell on one side, and auxiliary probe branches respectively used for connecting the positive electrode poles of each battery cell through the auxiliary probes on one side. The other side of the auxiliary probe branch is used for connecting one of the positive and negative poles of the detection device, and the other side of the odd number detection branch and the even number detection branch is used for connecting the other pole of the detection device, so as to form a series loop comprising the detection device, the auxiliary probe branch for connecting the detection device, the positive electrode pole connected to the one side of the auxiliary probe branch, the insulation detection probe inserted into the positive electrode pole, the bus connected in parallel with the insulation detection probe, and the odd number detection branch or the even number detection branch connected to the bus.
6. The cell insulation detection apparatus according to claim 5, characterized by The detection device is a multimeter with built-in power supply.
7. The cell insulation detection device according to claim 5 or 6, characterized by, The probe circuit board is also included, and the connection nodes of one side of the auxiliary probe branch for connecting one of the positive and negative poles of the detection device and the connection nodes of one side of the odd and even detection branches for connecting the other of the positive and negative poles of the detection device are arranged on the probe circuit board.
8. The cell insulation detection apparatus according to claim 7, characterized by, The connection nodes of one side of the auxiliary probe branch for connecting one of the positive and negative poles of the detection device and the connection nodes of one side of the odd detection branch for connecting the other of the positive and negative poles of the detection device corresponding to the positive pole of the odd battery cell are arranged in the same side region of the probe circuit board, and the connection nodes of one side of the auxiliary probe branch for connecting one of the positive and negative poles of the detection device and the connection nodes of one side of the even detection branch for connecting the other of the positive and negative poles of the detection device corresponding to the positive pole of the even battery cell are arranged in the same side region of the probe circuit board.