Method and device for detecting conductive foreign matter in pole hole of end cover assembly and battery production system

Abstract

The invention discloses a method and a device for detecting conductive foreign matters in pole holes of an end cover assembly, and a battery production system. The detection method comprises the steps that a first conductive component is provided, and at least part of the first conductive component is inserted into a sealing ring of an end cover assembly; providing a second conductive member, and conductively connecting the second conductive member with the top cover sheet of the end cover assembly; a preset voltage is connected to the first conductive member and the second conductive member to form a circuit; and judging that the conductive foreign matter exists in the pole hole under the condition that the circuit is conducted, and judging that the conductive foreign matter does not exist in the pole hole under the condition that the circuit is not conducted. The voltage is applied between the first conductive component and the second conductive component, and the end cover with the conductive foreign matter in the pole hole can be detected by detecting parameters of a circuit, so that the probability of short circuit in the battery monomer is reduced, and the safety of the battery monomer is improved.

Description

Technical Field

[0001] This application relates to the field of battery manufacturing technology, specifically to a method and device for detecting conductive foreign objects inside the terminal hole of an end cap assembly, and a battery manufacturing system. Background Technology

[0002] The end cap assembly of a battery cell consists of two parts: a top cover and a bottom cover. The top cover is made of metal, while the bottom cover is made of non-metal. The top cover is formed into terminal holes through stamping or other methods. The terminals are installed on the side of the top cover facing away from the bottom cover. A sealing ring is provided between the terminals and the top cover, and the terminals are insulated from each other. The current problem is that the inner surface of the terminal holes contains conductive burrs, metal particles, or metal wires, which can cause internal short circuits in the battery cell, affecting its safety. Summary of the Invention

[0003] In view of the above problems, this application provides a method and device for detecting conductive foreign objects in the terminal hole of an end cap assembly, as well as a battery production system, which can improve the situation of conductive foreign objects in the terminal hole.

[0004] In a first aspect, this application provides a method for detecting conductive foreign matter inside the electrode post hole of an end cap assembly, including:

[0005] A first conductive member is provided, and at least a portion of the first conductive member is inserted into the sealing ring of the end cap assembly;

[0006] Provide a second conductive component, and make conductive connection between the second conductive component and the top cover plate of the end cover assembly;

[0007] A preset voltage is applied to the first conductive component and the second conductive component to form a circuit;

[0008] If the circuit is conducting, determine that there is a conductive foreign object inside the electrode hole; if the circuit is not conducting, determine that there is no conductive foreign object inside the electrode hole.

[0009] When there are burrs or other conductive foreign objects in the terminal hole, after the end cap, sealing ring, and terminal are assembled, the conductive foreign objects may protrude from the surface where the end cap and sealing ring mate, potentially causing a short circuit in the battery cell and affecting its safety. By inserting the first conductive component into the sealing ring, under a preset voltage, if there are conductive foreign objects on the inner surface of the sealing ring, the foreign objects will either attach to the first conductive component or have a gap with it and discharge under the preset voltage, thus completing the circuit. Therefore, the presence of conductive foreign objects protruding from the inner surface of the sealing ring can be detected based on whether the circuit is continuous, reducing the probability of a short circuit in the battery cell and improving its safety.

[0010] Inserting at least a portion of the first conductive member into the sealing ring of the end cap assembly includes:

[0011] The first conductive component is configured to maintain a preset gap with the inner surface of the sealing ring.

[0012] This facilitates the insertion of the first conductive component into the sealing ring, reducing the probability of the sealing ring being deformed by the first conductive component, thereby improving the accuracy of the test results.

[0013] In some embodiments, the first conductive member is configured to be an insulated pole connected to the top cover plate, with one end of the pole abutting the first conductive member as the abutting end. Along the insertion direction of the first conductive member, the distance from the mating surface between the sealing ring and the lower cover plate of the end cover assembly to the abutting end is S1, and the preset gap is S2. At least one of S1 and S2 is set to a discharge distance less than or equal to a preset voltage.

[0014] When S1 is less than or equal to the discharge distance of the preset voltage, if there is a conductive foreign object on the inner surface of the sealing ring, the air between the conductive foreign object and the electrode will break down and discharge through the preset voltage to achieve circuit continuity, or the air will directly contact the electrode or the first conductive component to achieve circuit continuity. When S2 is less than or equal to the discharge distance of the preset voltage, the air between the conductive foreign object and the first conductive component will break down and discharge through the preset voltage to achieve circuit continuity, or the air will directly contact the electrode or the first conductive component to achieve circuit continuity. When both S1 and S2 are set to be less than or equal to the discharge distance of the preset voltage, the air between the conductive foreign object and the electrode will break down and discharge through the preset voltage, and / or the air between the conductive foreign object and the first conductive component will break down and discharge through the preset voltage to achieve circuit continuity, or the air will directly contact the electrode and / or the first conductive component to achieve circuit continuity. Therefore, setting at least one of S1 and S2 to be less than or equal to the discharge distance of the preset voltage can reduce the probability of missed detection of conductive foreign objects inside the sealing ring, thereby improving the accuracy of the detection results.

[0015] In some embodiments, S2 is set to a discharge distance less than or equal to a preset voltage, and the value range of S2 is set to between 0 and 0.2 mm.

[0016] When the radius R of the arc surface is large, the arc surface will be positioned opposite the electrode hole. If there is a conductive foreign object inside the electrode hole, and this foreign object is between the arc surface and the electrode hole, in order to allow the air between the conductive foreign object and the arc surface to be broken down and discharged, S2 is set to a discharge distance less than or equal to the preset voltage. When S2 = 0, the first conductive member is in contact with the inner surface of the sealing ring. When there is a conductive foreign object on the inner surface of the sealing ring, the conductive foreign object makes electrical contact with the first conductive member, thus conducting the circuit. As S2 increases, it facilitates the insertion of the first conductive member into the sealing ring, and also allows the circuit to be conducted by breaking down and discharging the air between the conductive foreign object and the first conductive member. However, if S2 is too large, the required preset voltage will also increase, and the generated arc may burn the sealing ring. Therefore, S2 is set between 0 and 0.2 mm.

[0017] In some embodiments, the value of S2 is set between 0.05mm and 0.15mm. Setting S2 to 0.05mm reduces the difficulty of insertion between the sealing ring and the first conductive component. As S2 increases, the insertion difficulty between the sealing ring and the first conductive component decreases, but the required preset voltage also increases, and the resulting arc may burn out the sealing ring. To reduce the risk of the sealing ring burning out while also considering the insertion difficulty between the sealing ring and the first conductive component, the value of S2 is set between 0.05mm and 0.15mm.

[0018] In some embodiments, the detection method further includes:

[0019] The edge of the insertion end of the first conductive component is set as a convex arc surface.

[0020] The first conductive component can be limited by the electrode post inside the electrode post hole, allowing the first conductive component to be inserted deep enough to increase the detection range, thereby reducing the probability of missed detection due to conductive foreign objects inside the electrode post hole.

[0021] In some embodiments, the radius of the arc surface is R, and the value of R is set to be between 1mm and 1.5mm.

[0022] Setting R between 1mm and 1.5mm allows the first conductive component to pass through the sealing ring and abut against the pole post. On the other hand, it makes the preset gap more uniform. (If R is too large, some of the arc surface will be opposite to the inner wall of the pole post hole, which reduces the probability of missing the detection of conductive foreign objects in the pole post hole due to excessive local gaps. (If R is too large, it will increase the local gap between the pole post hole and the first conductive component, which may increase the gap between conductive foreign objects and the first conductive component.)

[0023] In some embodiments, along the radial direction of the sealing ring, the gap between at least a portion of the arcuate surface and the inner surface of the sealing ring is set to a discharge distance less than or equal to a preset voltage.

[0024] When the radius (R) of the arc surface is large, it will be positioned opposite the inner surface of the sealing ring. If there are conductive foreign objects on the inner surface of the sealing ring, these objects will be located between the arc surface and the electrode hole. Due to the influence of the arc surface, the preset gap varies along the insertion direction of the first conductive component. During the detection process, if the gap between some positions of the arc surface and the inner surface of the sealing ring is too large and exceeds the discharge distance, conductive foreign objects on the inner surface of the sealing ring may be missed. Therefore, setting the gap between at least a portion of the arc surface and the inner surface of the sealing ring to be less than or equal to the discharge distance of the preset voltage can reduce the probability of missed conductive foreign objects and improve the accuracy of the detection results.

[0025] In some embodiments, inserting at least a portion of the first conductive member into the sealing ring of the end cap assembly includes:

[0026] A positioning mechanism is provided to position the end cap assembly along a first direction and a second direction, both of which are perpendicular to the insertion direction of the first conductive member.

[0027] This improves the insertion accuracy between the first conductive component and the electrode hole, reduces the probability of the first conductive component deviating from the predetermined insertion position, and improves the accuracy of the detection results.

[0028] In some embodiments, inserting at least a portion of the first conductive member into the sealing ring of the end cap assembly further includes:

[0029] Clamp the end cap assembly.

[0030] The end cap assembly is positioned first and then clamped to reduce the probability of the first conductive component deviating from the predetermined position during the detection process, thereby improving the accuracy of the detection.

[0031] In some embodiments, determining the presence of conductive foreign matter in the electrode hole based on circuit continuity, and determining the absence of conductive foreign matter in the electrode hole based on circuit decontinuity, includes:

[0032] If the resistance value of the circuit is less than or equal to the preset resistance value, it is determined that there is a conductive foreign object inside the terminal hole; if the resistance value is greater than the preset resistance value, it is determined that there is no conductive foreign object inside the terminal.

[0033] And / or, if the current value of the circuit is greater than zero, it is determined that there is a conductive foreign object inside the terminal hole; if the current value is zero, it is determined that there is no conductive foreign object inside the terminal.

[0034] Therefore, based on the detected resistance and / or current values, it can be determined whether there are conductive foreign objects inside the terminal hole, thereby reducing the probability of short circuits inside the battery cell and improving the safety of the battery cell.

[0035] Secondly, this application provides a detection device for conductive foreign matter inside the pole hole of an end cap assembly, the detection device comprising:

[0036] Base;

[0037] A first conductive member is disposed on the base. The first conductive member has an insertion part. The first conductive member is configured to be driven so that the insertion part is inserted into the pole hole and maintains a preset gap with the inner wall of the pole hole.

[0038] A second conductive component is disposed on the base. At least one of the first and second conductive components is insulated from the base. The second conductive component is used to conductively connect with the top cover plate of the end cover assembly. The first and second conductive components are configured to be supplied with a preset voltage.

[0039] When there are burrs or other conductive foreign objects in the terminal hole, after the end cap, sealing ring, and terminal are assembled, the conductive foreign objects may protrude from the surface where the end cap and sealing ring mate, potentially causing a short circuit in the battery cell and affecting its safety. By inserting the first conductive component into the sealing ring, under a preset voltage, if there are conductive foreign objects on the inner surface of the sealing ring, the foreign objects will either attach to the first conductive component or have a gap with it and discharge under the preset voltage, thus completing the circuit. Therefore, the presence of conductive foreign objects protruding from the inner surface of the sealing ring can be detected based on whether the circuit is continuous, reducing the probability of a short circuit in the battery cell and improving its safety.

[0040] In some embodiments, the insertion portion includes an end face and a side face, which are connected by an outwardly convex arc surface.

[0041] The first conductive component can be limited by the pole in the pole hole so that the first conductive component can be inserted deep enough. Since the pole and the end cap are insulated and sealed by a sealing ring, the first conductive component needs to pass through the sealing ring and abut against the pole. The arc surface can make the first conductive component pass through the sealing ring more smoothly.

[0042] In some embodiments, the radius of the arc surface is R, and the value of R ranges from 1mm to 1.5mm.

[0043] Setting R between 1mm and 1.5mm allows the first conductive component to pass through the sealing ring and abut against the pole post. On the other hand, it makes the preset gap more uniform. (If R is too large, some of the arc surface will be opposite to the inner wall of the pole post hole, which reduces the probability of missing the detection of conductive foreign objects in the pole post hole due to excessive local gaps. (If R is too large, it will increase the local gap between the pole post hole and the first conductive component, which may increase the gap between conductive foreign objects and the first conductive component.)

[0044] In some embodiments, the detection device further includes a clamping mechanism for clamping the end cap assembly.

[0045] Therefore, the end cap assembly can be fixed by the clamping mechanism, thereby reducing the probability of the end cap assembly moving during the inspection process and improving the accuracy of the inspection.

[0046] In some embodiments, the detection device further includes a limiting member, which is spaced apart from the second conductive member along the driving direction of the first conductive member, and at least one of the limiting member and the second conductive member is configured to be driven to jointly clamp the end cap assembly.

[0047] Therefore, the end cap assembly can be clamped by at least one of the limiting member and the second conductive member, so as to reduce the probability of the end cap assembly moving during the detection process and thus improve the accuracy of the detection.

[0048] In some embodiments, the limiting member includes a first limiting member and a second limiting member, the first limiting member and the second limiting member being spaced apart along a first direction, one of the first limiting member and the second limiting member being connected to a base, and the other of the first limiting member and the second limiting member being driven to clamp the end cap assembly between the first limiting member and the second conductive member, the second conductive member being disposed between the first limiting member and the second limiting member along a first direction, the first direction being perpendicular to the insertion direction of the first conductive member.

[0049] This reduces the deformation of the end cap assembly during clamping, thereby lowering the probability of the end cap being damaged due to excessive deformation.

[0050] In some embodiments, the first conductive member includes a conductive rod having an insertion portion, the cross-sectional profile of which is circular or square and the cross-section is perpendicular to the length direction of the conductive rod.

[0051] When the cross-sectional profile of the insertion part is circular, it can detect conductive foreign objects in a circular electrode hole. When the cross-sectional profile of the insertion part is square, it can detect conductive foreign objects in a square electrode hole, thus meeting the detection requirements of electrode holes of different shapes.

[0052] In some embodiments, the detection device further includes a positioning mechanism for positioning the end cap assembly along a first direction and a second direction, both of which are perpendicular to the insertion direction of the first conductive member.

[0053] This improves the positional accuracy of the end cap assembly during installation, allowing the first conductive component and the sealing ring to be inserted in the predetermined position, thereby improving the accuracy of the test results.

[0054] In some embodiments, the detection device further includes a first positioning member and a second positioning member, both of which are disposed on the base. The first positioning member is used to position the end cap assembly along a first direction, and the second positioning member is used to position the end cap assembly along a second direction.

[0055] Alternatively, the detection device may further include a third positioning element connected to the base. The third positioning element has a limiting groove on its side opposite to the base, which is used to accommodate a portion of the end cap assembly for positioning the end cap assembly along the first and second directions.

[0056] Both the first direction and the second direction are perpendicular to the insertion direction of the first conductive member, and the first direction and the second direction are perpendicular.

[0057] This improves the insertion accuracy between the first conductive component and the electrode hole, thereby reducing the probability that the first conductive component deviates from the predetermined insertion position, and thus reducing the probability that conductive foreign objects in the electrode hole are missed or falsely detected.

[0058] Thirdly, a battery production system is provided, including a detection device for conductive foreign matter inside the terminal hole of the end cap assembly of the second aspect, the detection device being used to detect whether there is conductive foreign matter inside the terminal hole of the end cap assembly of the battery cell.

[0059] Since the battery production system includes all the technical features of the detection method described in the above embodiments, or includes all the technical features of the detection device, the effect is the same as described above, and will not be repeated here.

[0060] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, the following are specific embodiments of this application. Attached Figure Description

[0061] Various other advantages and benefits will become apparent to those skilled in the art upon reading the detailed description of the preferred embodiments below. The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of this application. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:

[0062] Figure 1 This is a cross-sectional view of the axis of the through-hole in the end cap according to an embodiment of this application;

[0063] Figure 2 This is a structural diagram of an embodiment of the present application, showing the first conductive member inserted into the electrode hole and the second conductive member electrically connected to the end cap.

[0064] Figure 3This is a cross-sectional view of the axis of the electrode hole after the first conductive member is inserted into the electrode hole according to an embodiment of this application;

[0065] Figure 4 This is a structural diagram of the current according to an embodiment of this application;

[0066] Figure 5 This is an isometric view of a detection device according to an embodiment of this application from a first perspective;

[0067] Figure 6 This is an isometric view of the detection device according to another embodiment of this application from a first perspective;

[0068] Figure 7 This is an isometric view of a detection device according to an embodiment of this application from a second perspective;

[0069] Figure 8 This is an isometric view of the detection device according to another embodiment of this application from a second perspective;

[0070] Figure 9 This is an isometric view of the detection device according to another embodiment of this application from a first perspective.

[0071] The reference numerals in the detailed embodiments are as follows:

[0072] 100. Detection device;

[0073] 10. Base; 20. First conductive component; 21. Conductive rod; 211. Side; 212. End face; 213. Arc surface; 22. First connecting component; 23. Second connecting component; 30. Second conductive component; 40. Limiting component; 41. First limiting component; 42. Second limiting component; 50. Adapter; 60. Positioning mechanism; 61. First positioning component; 62. Second positioning component; 63. Third positioning component; 631. Limiting groove; 70. High voltage detector;

[0074] 200. End cap assembly; 210. End cap; 2101. Top cover plate; 2102. Lower cover plate; 2103. Pole post hole; 220. Sealing ring; 230. Pole post;

[0075] 300. Conductive foreign object; 400. Detection component; 500. Power supply;

[0076] X, insertion direction; Y, first direction; Z, second direction. Detailed Implementation

[0077] The embodiments of the technical solution of this application will now be described in detail with reference to the accompanying drawings. These embodiments are only used to more clearly illustrate the technical solution of this application and are therefore merely examples, and should not be used to limit the scope of protection of this application.

[0078] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms “comprising” and “having”, and any variations thereof, in the specification, claims, and foregoing description of the drawings are intended to cover non-exclusive inclusion.

[0079] In the description of the embodiments of this application, technical terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, "multiple" means two or more, unless otherwise explicitly defined.

[0080] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0081] In the description of the embodiments in this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this document generally indicates that the preceding and following related objects have an "or" relationship.

[0082] In the description of the embodiments of this application, the term "multiple" refers to two or more (including two), similarly, "multiple sets" refers to two or more (including two sets), and "multiple pieces" refers to two or more (including two pieces).

[0083] In the description of the embodiments of this application, the technical terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application.

[0084] In the description of the embodiments of this application, unless otherwise expressly specified and limited, technical terms such as "installation," "connection," "joining," and "fixing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. For those skilled in the art, the specific meaning of the above terms in the embodiments of this application can be understood according to the specific circumstances.

[0085] Please refer to Figure 1 The end cap assembly 200 of the battery cell has two parts: a top cover plate 210 end cap 2101 and a lower cover plate 2102. The top cover plate 210 is made of metal, while the lower cover plate 2102 is made of non-metallic material. The top cover plate 2101 is made by stamping or other means to form some terminal post holes 2103. The lower cover plate has some terminal post holes 2103, and the terminal post 230 is installed on the top cover plate 210 end cap. The side of 2101 facing away from the lower cover plate 2102 is connected to the top cover plate 210 end cap. A sealing ring 220 is provided between 2101 and the terminal post 230 and the top cover plate 210 end cap. 2101 is insulated. Because the pole hole 2103 of the top cover plate 210 end cap 2101 is manufactured by stamping or other methods, the surface is prone to having conductive foreign objects 300 such as burrs or metal wires. After the top cover plate 210 end cap 2101, the lower cover plate 2102, the sealing ring 220, and the pole 230 are installed, the conductive foreign objects 300 can easily protrude from between the mating surfaces of the sealing ring 220 and the lower cover plate 2102. Figure 1 The part indicated by B extends to the inner surface of the sealing ring 220. The conductive foreign object 300 can easily cause the terminal post 230 to make electrical contact with the end cap, which can easily cause an internal short circuit in the battery cell and affect the safety of the battery cell.

[0086] In view of this, this application provides a method for detecting conductive foreign objects 300 inside the terminal hole 2103 of the end cap assembly 200. When there are conductive foreign objects 300 such as burrs in the terminal hole 2103, after the end cap, sealing ring 220 and terminal 230 are assembled, the conductive foreign objects 300 may protrude from the surface where the end cap and sealing ring 220 mate, which may cause a short circuit in the battery cell and affect the safety of the battery cell. By inserting the first conductive member 20 into the sealing ring 220, under a preset voltage, if there are conductive foreign objects 300 on the inner surface of the sealing ring 220, the conductive foreign objects 300 will overlap the first conductive member 20, or there will be a gap between the conductive foreign objects 300 and the first conductive member 20 and they will discharge under the preset voltage to conduct the circuit. Thus, the conductive foreign objects 300 protruding from the inner surface of the sealing ring 220 can be detected according to whether the circuit is conducting, thereby reducing the probability of a short circuit in the battery cell and improving the safety of the battery cell.

[0087] The detection method of this application is used for, but is not limited to, the detection of conductive foreign matter 300 in the end cap inner pole hole 2103.

[0088] For ease of explanation, please refer to the following examples. Figures 1-9 The following is an example of a method for detecting conductive foreign matter 300 in the pole hole 2103 of an end cap assembly 200 according to some embodiments of this application.

[0089] The detection method is used to detect conductive foreign matter 300 inside the terminal hole 2103 of the end cap of a battery cell. The detection method includes:

[0090] A first conductive member 20 is provided, and at least a portion of the first conductive member 20 is inserted into the sealing ring 220 of the end cap assembly 200;

[0091] A second conductive member 30 is provided, and the second conductive member 30 is conductively connected to the top cover plate 210 end cover 2101 of the end cover assembly 200;

[0092] A preset voltage is applied to the first conductive component 20 and the second conductive component 30 to form a circuit;

[0093] When the circuit is conducting, it is determined that there is a conductive foreign object 300 inside the electrode hole 2103; when the circuit is not conducting, it is determined that there is no conductive foreign object 300 inside the electrode hole 2103.

[0094] When there are conductive foreign objects 300 such as burrs in the terminal hole 2103, after the end cap, sealing ring 220 and terminal 230 are assembled, the conductive foreign objects 300 may protrude from the surface where the end cap and sealing ring 220 mate, which may cause a short circuit in the battery cell and affect the safety of the battery cell. When the first conductive member 20 is inserted into the sealing ring 220, under a preset voltage, if there are conductive foreign objects 300 on the inner surface of the sealing ring 220, the conductive foreign objects 300 will overlap the first conductive member 20, or there will be a gap between the conductive foreign objects 300 and the first conductive member 20 and they will discharge under the preset voltage to conduct the circuit. Thus, the conductive foreign objects 300 protruding from the inner surface of the sealing ring 220 can be detected according to whether the circuit is conducting, so as to reduce the probability of short circuit in the battery cell and improve the safety of the battery cell.

[0095] Both the first conductive component 20 and the second conductive component 30 can be made of metal or conductive non-metallic material. They can also be integral components formed by connecting metal and non-metallic parts. The metal part is inserted into the pole hole 2103 and a preset voltage is applied to the metal part.

[0096] "Conduction" refers to the formation of a path between the first conductive member 20 and the second conductive member 30 by electrical connection (connecting the two by the conductive foreign object 300) or by voltage breakdown of the air between the conductive foreign object 300 and the first conductive member 20.

[0097] The first conductive component 20 and the second conductive component 30 can be connected to the power supply 500 via wires. The wires can be connected in series or in parallel with electrical components, such as indicator lights, resistors, or alarm devices. When the voltage is low, electrical components may not be required. Alternatively, the power supply 500 can be used to supply a preset voltage to the first conductive component 20 and the second conductive component 30.

[0098] Please refer to Figure 4 Whether the circuit is conductive can be detected by the detection component 400 in the circuit. The power supply 500 provides a preset voltage. The detection component 400 can be, but is not limited to, an indicator light, an alarm device, an ammeter, or a resistor detection instrument. When the circuit is conductive, the conductive foreign object 300 forms a closed circuit; when the circuit is not conductive, it is open. The difference in current and / or resistance between a closed and open circuit can be used to determine whether the circuit is conductive. Alternatively, the continuity can be determined by whether the indicator light flashes or whether the alarm device issues an alarm. Figure 2 As shown, a high-voltage detector 70 can also be electrically connected between the first conductive member 20 and the second conductive member 30. The high-voltage detector 70 applies a preset voltage to the first conductive member 20 and the second conductive member 30, and then detects the current and / or resistance to determine whether the circuit is conductive. In another example, a preset gap can be set between the first conductive member 20 and the inner surface of the sealing ring 220. By moving the first conductive member 20 along the circumferential direction of the sealing ring 220, the conductive foreign object 300 can be detected. When there is a conductive foreign object 300 on the inner surface of the sealing ring 220, the first conductive member 200 makes brief electrical contact with the conductive foreign object 300 through movement, thus achieving circuit continuity. Therefore, the presence of a conductive foreign object 300 can be determined based on circuit continuity.

[0099] When there are conductive foreign objects 300 such as burrs in the terminal hole 2103, after the end cap, sealing ring 220 and terminal 230 are assembled, the conductive foreign objects 300 may protrude from the surface where the end cap and sealing ring 220 mate, which may cause a short circuit in the battery cell and affect the safety of the battery cell. When the first conductive member 20 is inserted into the sealing ring 220, under a preset voltage, if there are conductive foreign objects 300 on the inner surface of the sealing ring 220, the conductive foreign objects 300 will overlap the first conductive member 20, or there will be a gap between the conductive foreign objects 300 and the first conductive member 20 and they will discharge under the preset voltage to conduct the circuit. Thus, the conductive foreign objects 300 protruding from the inner surface of the sealing ring 220 can be detected according to whether the circuit is conducting, so as to reduce the probability of short circuit in the battery cell and improve the safety of the battery cell.

[0100] Inserting at least a portion of the first conductive member 20 into the sealing ring 220 of the end cap assembly 200 includes:

[0101] The first conductive member 20 is configured to maintain a preset gap with the inner surface of the sealing ring 220.

[0102] The preset gap can be uniform or non-uniform. For example, during the insertion of the first conductive component 20 and the first sealing ring 220, due to assembly errors, the preset gap may be larger on one side and smaller on the other.

[0103] This facilitates the insertion of the first conductive member 20 into the sealing ring 220, thereby reducing the probability of the sealing ring 220 being deformed by the first conductive member 20 and improving the accuracy of the detection results.

[0104] In some embodiments, the first conductive member 20 is configured to abut against the pole post 230 which is insulated from the top cover plate 210. The end of the pole post 230 that abuts against the first conductive member 20 is the abutting end. Along the insertion direction X of the first conductive member 20, the distance from the mating surface between the sealing ring 220 and the lower cover plate 2102 of the end cover assembly 200 to the abutting end is S1, and the preset gap is S2. At least one of S1 and S2 is set to a discharge distance that is less than or equal to a preset voltage.

[0105] The discharge distance refers to the minimum distance between two conductors under a preset voltage.

[0106] When the preset gap is uneven, the discharge distance where S2 is less than or equal to the preset voltage means that the maximum value of S2 is less than or equal to the discharge distance of the preset voltage.

[0107] When S1 is less than or equal to the discharge distance of the preset voltage, if a conductive foreign object 300 is present on the inner surface of the sealing ring 220, the air between the conductive foreign object 300 and the electrode 230 will achieve circuit conduction through a breakdown discharge at the preset voltage, or directly make electrical contact with the electrode 230 or the first conductive member 20 to achieve circuit conduction. When S2 is less than or equal to the discharge distance of the preset voltage, the air between the conductive foreign object 300 and the first conductive member 20 will achieve circuit conduction through a breakdown discharge at the preset voltage, or directly make electrical contact with the electrode 230 or the first conductive member 20 to achieve circuit conduction. When both S1 and S2 are set to be less than or equal to the discharge distance of the preset voltage, the air between the conductive foreign object 300 and the electrode 230 will achieve circuit conduction through a breakdown discharge at the preset voltage and / or the air between the conductive foreign object 300 and the first conductive member 20 will achieve circuit conduction through a breakdown discharge at the preset voltage, or directly make electrical contact with the electrode 230 and / or the first conductive member 20 to achieve circuit conduction. Therefore, setting at least one of S1 and S2 to a discharge distance less than or equal to a preset voltage can reduce the probability of missing a conductive foreign object 300 within the sealing ring 220, thereby improving the accuracy of the detection results. In other embodiments, along the insertion direction X of the first conductive member 20, the first conductive member 20 can also be configured as poles 230 spaced apart, that is, the first conductive member 20 is inserted partially into the sealing ring 220. In this case, the discharge distance in S2 can be set to be less than or equal to the preset voltage.

[0108] In some embodiments, please refer to Figure 3 Set S2 to a discharge distance less than or equal to the preset voltage, and set the value range of S2 to between 0 and 0.2 mm.

[0109] When the radius R of the arc surface 213 is large, the arc surface 213 will be positioned opposite the electrode hole 2103. If there is a conductive foreign object 300 inside the electrode hole 2103, and the conductive foreign object 300 is between the arc surface 213 and the electrode hole 2103, in order to allow the air between the conductive foreign object 300 and the arc surface 213 to be broken down and discharged, S2 is set to a discharge distance less than or equal to the preset voltage. When S2 = 0, the first conductive member 20 is in contact with the inner surface of the sealing ring 220. When there is a conductive foreign object 300 on the inner surface of the sealing ring 220, the conductive foreign object 300 makes electrical contact with the first conductive member 20 and conducts the circuit. As S2 increases, on the one hand, it facilitates the insertion of the first conductive member 20 and the sealing ring 220, and on the other hand, it can conduct the circuit by breaking down and discharging the air between the conductive foreign object 300 and the first conductive member 20. However, if S2 is too large, the required preset voltage will also increase, and the generated arc may burn the sealing ring 220. Therefore, S2 is set to between 0 and 0.2 mm.

[0110] In some embodiments, the value of S2 is set between 0.05mm and 0.15mm. Setting S2 to 0.05mm reduces the difficulty of insertion between the sealing ring 220 and the first conductive member 20. As S2 increases, the insertion difficulty between the sealing ring 220 and the first conductive member 20 decreases, but the required preset voltage also increases, and the resulting arc may burn out the sealing ring 220. To reduce the risk of the sealing ring 220 being burned out, while also considering the insertion difficulty between the sealing ring 220 and the first conductive member 20, the value of S2 is set between 0.05mm and 0.15mm.

[0111] In some embodiments, please refer to Figure 3 The detection method also includes setting the edge of the insertion end of the first conductive member 20 into a convex arc surface 213.

[0112] The first conductive member 20 can be limited by the pole post 230 in the pole post hole 2103 so that the first conductive member 20 can be inserted deep enough to increase the detection range, thereby reducing the probability of missed detection of conductive foreign objects 300 in the pole post hole 2103.

[0113] In some embodiments, please refer to Figure 3 The radius of the arc surface 213 is R, and the value of R is set to be between 1mm and 1.5mm.

[0114] Setting R between 1mm and 1.5mm allows the first conductive component 20 to pass through the sealing ring 220 and abut against the pole post 230. On the other hand, when the conductive foreign object 300 is located between the arc surface 213 and the sealing ring 220, if R is too large, the distance between the conductive foreign object 300 and the first conductive component 20 may be greater than the discharge distance, causing the conductive foreign object 300 to be missed. Setting R between 1mm and 1.5mm makes the gap between the arc surface 213 and the sealing ring 220 more uniform, reducing the probability of the conductive foreign object 300 being missed.

[0115] In some embodiments, along the radial direction of the sealing ring 220, the gap between at least a portion of the arcuate surface 213 and the inner surface of the sealing ring 220 is set to a discharge distance less than or equal to a preset voltage.

[0116] When the radius (R) of the arc surface 213 is large, it will cause the arc surface 213 to be positioned opposite the inner surface of the sealing ring 220. If there is a conductive foreign object 300 on the inner surface of the sealing ring 220, and the conductive foreign object 300 is between the arc surface 213 and the electrode hole 2103, the preset gap will vary along the insertion direction X of the first conductive member 20 due to the influence of the arc surface 213. During the detection process, if the gap between some positions of the arc surface 213 and the inner surface of the sealing ring 220 is too large and exceeds the discharge distance, it may cause the conductive foreign object 300 on the inner surface of the sealing ring 220 to be missed. Therefore, setting the gap between at least a portion of the arc surface 213 and the inner surface of the sealing ring 220 to be less than or equal to the discharge distance of the preset voltage can reduce the probability of the conductive foreign object 300 being missed, thereby improving the accuracy of the detection results.

[0117] In some embodiments, the detection method further includes:

[0118] The range of values ​​for the arc surface 213R is determined by setting the gap between at least a portion of the arc surface 213 and the inner surface of the sealing ring 220 to a discharge distance less than or equal to a preset voltage.

[0119] The gap between the arc surface 213 and the inner surface of the sealing ring 220 can be set to a discharge distance less than or equal to the preset voltage. An inequality about R can be established, and the range of values ​​for R can be determined by solving the inequality.

[0120] Therefore, the value of R can be reasonably controlled during the manufacturing of the first conductive component 20, so as to reduce the probability of the conductive foreign object 300 being missed due to excessive R during the detection process.

[0121] In some embodiments, please refer to Figure 3 The radius of the arc surface 213 is R, the distance between the two points with the largest distance on the outer contour line of the cross-section of the first conductive member 20 is D, the cross-section of the first conductive member 20 is perpendicular to the insertion direction X of the first conductive member 20, and R and D satisfy:

[0122]

[0123] Wherein, H is the detection compensation coefficient of the preset voltage, and the value of H is between 0.3mm and 0.8mm. A is the distance between the two points with the largest distance on the cross-section of the partial pole hole 2103 of the lower cover plate 2102. The cross-section of the partial pole hole 2103 of the lower cover plate 2102 is perpendicular to the insertion direction X of the first conductive member 20.

[0124] The preset voltage can be between 1000V and 10000V, or it can be set between 2000V and 8000V.

[0125] As an example, with a preset voltage of 2000V and a circular hole 2103, the distance A between the two points with the greatest distance on the cross-section of the hole 2103 is the diameter of the hole 2103, and the value of A ranges from 14.9mm to 14.95mm. H = 0.6, and R can be calculated to be between 1mm and 1.5mm. In a specific embodiment, a first conductive member 20 with a diameter of 14.9mm and R = 1mm can be inserted into the hole 2103. The first conductive member 20 is a circular rod. In other examples, the outline of the cross-section of the first conductive member 20 is the same as the outline of the cross-section of the hole 2103 (excluding the cross-sectional outline of the inner wall of the conductive foreign object 300) to make the preset gap more uniform at different positions.

[0126] The larger the value of H, the greater the preset voltage required for the conductive foreign object 300 to contact the first conductive member 20, and vice versa. An excessively high preset voltage discharge may cause the arc generated by the discharge to burn the sealing ring 220. Therefore, to reduce the risk of the sealing ring 220 being burned, and to facilitate the connection between the first conductive member 20 and the sealing ring 220 and reduce the risk of the sealing ring 220 being burned, H is set between 0.3mm and 0.8mm. The radius R is calculated based on H, A, and D to ensure that R is within a suitable range during the manufacturing of the first conductive member 20. This allows the first conductive member 20 to pass smoothly through the sealing ring 220 and contact the electrode post 230, and also reduces the probability of the conductive member being missed during inspection.

[0127] In some embodiments, the value of H ranges from 0.3 mm to 0.6 mm.

[0128] A value of H = 0.3 mm facilitates the insertion of the first conductive component 20 and the sealing ring 220. As H increases, the insertion becomes easier, but the required preset voltage also increases. Furthermore, the electric arc between the conductive foreign object 300 and the first conductive component 20 can easily burn out the sealing ring 220. To facilitate the insertion of the first conductive component 20 and the sealing ring 220 and to reduce the risk of the sealing ring 220 burning out, the value of H is set between 0.3 mm and 0.6 mm.

[0129] In some embodiments, inserting at least a portion of the first conductive member 20 into the sealing ring 220 of the end cap assembly 200 includes:

[0130] A positioning mechanism is provided to position the end cap assembly 200 along a first direction Y and a second direction Z. Both the first direction Y and the second direction Z are perpendicular to the insertion direction X of the first conductive member 20. The first direction Y and the second direction Z are perpendicular to each other.

[0131] As an example, the positioning mechanism includes a positioning plate with a positioning groove on one side along the second direction Z. A portion of the end cap assembly 200 is inserted into the positioning groove to position the end cap assembly 200 along the first direction Y and the second direction Z. In other examples, the positioning mechanism includes a base 10, a first positioning block, and a second positioning block. The base 10 has the first and second positioning blocks on the same side along the second direction Z. The first positioning block can be located on one side of the end cap along the second direction Z, and the second positioning block can be located on one side of the end cap assembly 200 along the first direction Y, so that the end cap assembly 200 is positioned along the first direction Y and the second direction Z through the first and second positioning blocks.

[0132] This improves the insertion accuracy between the first conductive component 20 and the electrode hole 2103, thereby reducing the probability that the first conductive component 20 deviates from the predetermined insertion position and improving the accuracy of the detection results.

[0133] In some embodiments, inserting at least a portion of the first conductive member 20 into the sealing ring 220 of the end cap assembly 200, the method further includes: clamping the end cap assembly 200.

[0134] The end cap assembly 200 can be clamped and fixed by means of pneumatic grippers or electric grippers, or a limiting member can be provided on the side of the end cap assembly 200 away from the second conductive member 30, and the end cap assembly 200 can be clamped and fixed by driving at least one of the limiting member and the second conductive member 30.

[0135] As an example, the first conductive component 20 can be driven by a linear motion mechanism to insert the first conductive component 20 into the pole hole 2103. The linear motion mechanism can be, but is not limited to, a linear module, an electric push rod, a cylinder or a hydraulic push rod, etc. The linear motion mechanism can also be a linear guide mechanism. The first conductive component 20 can be moved along the depth direction of the pole hole 2103 by manual, electric, pneumatic or hydraulic means, so as to play a guiding role when the first conductive component 20 is inserted, so that the first conductive component 20 can be inserted into the sealing ring 220 more accurately.

[0136] The end cap assembly 200 is positioned first and then clamped to reduce the probability of the first conductive component 20 deviating from the predetermined position during the detection process, thereby improving the accuracy of the detection.

[0137] In some embodiments, determining the presence of a conductive foreign object 300 within the electrode hole 2103 based on circuit continuity, and determining the absence of a conductive foreign object 300 within the electrode hole 2103 based on circuit deconduction, includes:

[0138] If the resistance value of the circuit is less than or equal to the preset resistance value, it is determined that there is a conductive foreign object 300 inside the terminal hole 2103; if the resistance value is greater than the preset resistance value, it is determined that there is no conductive foreign object 300 inside the terminal 230.

[0139] And / or, based on the circuit current value being greater than zero, it is determined that there is a conductive foreign object 300 inside the terminal hole 2103, and based on the current value being zero, it is determined that there is no conductive foreign object 300 inside the terminal 230.

[0140] Therefore, based on the detected resistance and / or current values, it can be determined whether there are conductive foreign objects 300 inside the terminal hole 2103, thereby reducing the probability of short circuits inside the battery cell and improving the safety of the battery cell.

[0141] For ease of explanation, please refer to the following examples. Figures 1-6 The following description will be based on an example of a device for detecting conductive foreign objects in the pole hole of an end cap assembly according to some embodiments of this application.

[0142] The detection device 100 is used to detect conductive foreign objects 300 inside the terminal hole 2103 of the end cap 200 of a battery cell. The detection device 100 includes a base 10, a first conductive member 20, and a second conductive member 30. The first conductive member 20 is disposed on the base 10 and has an insertion portion. The first conductive member 20 is configured to be driven so that the insertion portion is inserted into the terminal hole 2103 and maintains a preset gap with the inner wall of the terminal hole 2103. The second conductive member 30 is disposed on the base 10, and at least one of the first conductive member 20 and the second conductive member 30 is insulated from the base 10. The second conductive member 30 is used to conductively connect with the top cover plate 2101 of the end cap assembly 200. The first conductive member 20 and the second conductive member 30 are configured to be supplied with a preset voltage.

[0143] A component can be a single piece or an integral structure formed by connecting multiple components.

[0144] Electrical connection refers to a connection that enables the second conductive member 30 to conduct electricity with the metal part of the end cap 200. Specifically, it can be abutment or electrical connection can be achieved through conductive parts or other means.

[0145] The first conductive component 20 can be driven manually, electrically, pneumatically, or hydraulically.

[0146] For example, the first conductive component 20 can be connected to the pole hole 2103 by means of a cylinder drive.

[0147] The second conductive member 30 can be electrically connected to the end cap 200 by a drive, or it can be fixed to the base 10 and directly abutted against the metal part of the end cap 200 to achieve electrical connection. As an example, the second conductive member 30 can be driven by a drive component such as a cylinder, hydraulic push rod, or electric push rod via an adapter 50. The drive component moves the second conductive member 30, thus achieving electrical connection between the second conductive member 30 and the end cap 200. In other examples, the second conductive member 30 can be disposed on the adapter 50. The connection between the second conductive member 30 and the adapter 50 includes, but is not limited to, threaded connection, screw connection, or bonding. The adapter 50 is connected to the base 10, and the connection between the adapter 50 and the base 10 includes, but is not limited to, screw connection, riveting, or welding.

[0148] The base 10 can be an insulating component. At least one of the first conductive member 20 and the second conductive member 30 can also be insulated from the base 10 by an insulating component, such as an insulating board or insulating adhesive. The insulating component separates at least one of the first conductive member 20 and the second conductive member 30 from the base 10, thereby achieving insulation between the first conductive member 20 and the second conductive member 30 and the base 10. Two bases 10 can be provided and spaced apart along the insertion direction X. The first conductive member 20 is provided on one base 10 and the second conductive member 30 is provided on the other base 10 to avoid short-circuiting of the first conductive member 20 and the second conductive member 30 through the base 10 after energization, which would affect the judgment result.

[0149] As an example, the first conductive component 20 includes a conductive rod 21, a connecting component, and a first driving component. The conductive rod 21 is driven to connect with the first driving component through the connecting component. Specifically, the connecting component may include a first connecting component 22 and a second connecting component 23. The first connecting component 22 and the second connecting component 23 can be fixed by means of screw connection, riveting, or welding to jointly clamp and fix the conductive rod 21. The second connecting component 23 is driven to connect with the first driving component. The first driving component is used to drive the connecting component and the conductive rod 21 to move, so as to realize the insertion of the conductive rod 21 into the electrode hole 2103. Both the first connecting component 22 and the second connecting component 23 can be insulators. A terminal bar or terminal post can be provided on the side of the conductive rod 21 away from the end cover 200 to facilitate electrical connection to one end of the power supply through a wire.

[0150] When there are conductive foreign objects 300 such as burrs on the inner surface of the terminal hole 2103 of the end cap 200, the first conductive member 20 is inserted into the terminal hole 2103. The conductive foreign object 300 can make the first conductive member 20 and the terminal hole 2103 electrically conductive. If there is no conductive foreign object 300, the first conductive member 20 and the terminal hole 2103 are in an insulating state. Therefore, when a voltage is applied between the first conductive member 20 and the second conductive member 30, the presence of conductive foreign objects 300 can be determined by detecting the parameters between the first conductive member 20 and the second conductive member 30, such as resistance and current. This allows for the identification of end caps 200 with conductive foreign objects 300 inside the terminal hole 2103, thereby reducing the probability of short circuits inside the battery cell and improving the safety of the battery cell.

[0151] In some embodiments, the insertion portion includes an end face 212 and a side face 211, which are connected by an outwardly convex arc surface 213.

[0152] The first conductive member 20 can be limited by the pole post 230 in the pole post hole 2103 so that the first conductive member 20 can be inserted deep enough. Since the pole post 230 and the end cap 200 are insulated and sealed by the sealing ring 202, the first conductive member 20 needs to pass through the sealing ring 202 and abut against the pole post 230. The arc surface 213 can make the first conductive member 20 pass through the sealing ring 202 more smoothly.

[0153] In some embodiments, the radius of the arc surface is R, and the value of R ranges from 1mm to 1.5mm.

[0154] Setting R between 1mm and 1.5mm allows the first conductive component 20 to pass through the sealing ring 202 and abut against the pole post 230. On the other hand, it makes the preset gap more uniform. (If R is too large, some arc surfaces will be opposite to the inner wall of the pole post hole 2103, which reduces the probability of missing the detection of conductive foreign objects 300 in the pole post hole 2103 due to excessive local gaps. (If R is too large, it will increase the local gap between the pole post hole 2103 and the first conductive component 20, which may increase the gap between the conductive foreign object 300 and the first conductive component 20.)

[0155] In some embodiments, the detection device 100 further includes a limiting member 40, which is spaced apart from the second conductive member 30 along the driving direction of the first conductive member 20. At least one of the limiting member 40 and the second conductive member 30 is configured to be driven so as to jointly clamp the end cap 200.

[0156] As an example, the limiting member 40 includes a driven member and a second driving member. The driven member and the second conductive member 30 are spaced apart along the driving direction of the first conductive member 20. The driven member and the second driving member are drivenly connected. The second driving member is used to drive the driven member to move along the driving direction of the first conductive member 20. The second driving member can be, but is not limited to, a linear second driving member such as a cylinder, an electric push rod, or a hydraulic push rod.

[0157] Therefore, the end cap 200 can be clamped by at least one of the limiting member 40 and the second conductive member 30, so as to reduce the probability of the end cap 200 moving during the detection process and thus improve the accuracy of the detection.

[0158] In some embodiments, the limiting member 40 includes a first limiting member 41 and a second limiting member 42, which are spaced apart along a first direction Y. One of the first limiting member 41 and the second limiting member 42 is connected to the base 10, and the other of the first limiting member 41 and the second limiting member 42 is configured to be driven so that the first limiting member 41 and the second conductive member 30 clamp the end cap 200. The second conductive member 30 is disposed between the first limiting member 41 and the second limiting member 42 along the first direction Y, which is perpendicular to the insertion direction X of the first conductive member 20.

[0159] As an example, there are two first limiting members 41 and two second limiting members 42. The two first limiting members 41 can be disposed between the two second limiting members 42 and driven by a driving component to achieve movement along the insertion direction X. The second conductive member 30 is configured as follows:

[0160] This reduces the deformation of the end cap 200 during clamping, thereby lowering the probability of the end cap 200 being damaged due to excessive deformation.

[0161] In some embodiments, the first conductive member 20 includes a conductive rod 21, which has an insertion portion. The cross-sectional profile of the insertion portion is any one of a circle, an ellipse, a square, or a polygon, and the cross-section is perpendicular to the length direction of the conductive rod 21.

[0162] When the cross-sectional outline of the insertion part is circular, conductive foreign objects 300 within the circular electrode hole 2103 can be detected. When the cross-sectional outline of the insertion part is square, conductive foreign objects 300 within the square electrode hole 2103 can be detected, thus meeting the detection requirements of electrode holes 2103 of different shapes. In other examples, the first conductive member 20 can be a block structure, a plate structure, or other irregularly shaped structures. For example, the insertion part can be set to be circular, and the cross-sectional outline of the part not inserted into the electrode hole 2103 can be set to an irregularly shaped structure such as square, triangle, or ellipse, which can be set according to actual needs. For example, the first conductive member 20 is a plate structure, and the insertion part can be a boss of the plate structure.

[0163] The detection device 100 provided in the above embodiments of this application can be used in the above detection method to detect conductive foreign matter 300 in the terminal hole 2103 of the end cap assembly 200, so as to determine whether there is conductive foreign matter 300 in the terminal hole 2103. In the battery production process, the quality of the end cap assembly 200 can be improved, thereby reducing the probability of short circuit inside the battery cell.

[0164] In some embodiments, the detection device 100 further includes a positioning mechanism 60, which is used to position the end cap assembly 200 along a first direction Y and a second direction Z. Both the first direction Y and the second direction Z are perpendicular to the insertion direction X of the first conductive member 20, and the first direction Y and the second direction Z are perpendicular to each other.

[0165] The positioning mechanism 60 can be, but is not limited to, the structures listed above.

[0166] This improves the positional accuracy of the end cap assembly 200 during installation, allowing the first conductive member 20 and the sealing ring 220 to be inserted in the predetermined position, thereby improving the accuracy of the test results.

[0167] In one embodiment, the positioning mechanism 60 includes a first positioning member 61 and a second positioning member 62, both of which are disposed on the base 10. The first positioning member 61 is used to restrict the movement of the end cap 200 along a first direction Y, and the second positioning member 62 is used to restrict the movement of the end cap 200 along a second direction Z. Both the first direction Y and the second direction Z are perpendicular to the insertion direction X of the first conductive member 20, and the first direction Y and the second direction Z are perpendicular to each other. In another embodiment, the positioning mechanism 60 further includes a third positioning member 63, which is connected to the base 10. The third positioning member 63 has a limiting groove 631 on the side facing away from the base 10. The limiting groove 631 is used to accommodate part of the end cap 200 to restrict the movement of the end cap 200 along the first direction Y and the second direction Z. Both the first direction Y and the second direction Z are perpendicular to the insertion direction X of the first conductive member 20, and the first direction Y and the second direction Z are perpendicular to each other.

[0168] The end cap 200 has a first positioning member 61 on at least one side along the first direction Y. As an example, there can be two first positioning members 61, spaced apart along the first direction Y, to restrict the movement of the end cap 200 along the first direction Y. A second positioning member 62 restricts the movement of the end cap 200 along the second direction Z; during positioning, the end cap 200 is positioned on top of the second positioning member 62. There can be one or more second positioning members 62. For example, there can be multiple second positioning members 62 arranged along the first direction Y. The first positioning member 61 and the second positioning member 62 can be connected to the base 10 by screws, rivets, positioning pins, etc., or they can be integrally formed with the base 10.

[0169] This improves the insertion accuracy between the first conductive member 20 and the electrode hole 2103, thereby reducing the probability that the first conductive member 20 deviates from the predetermined insertion position.

[0170] The detection device 100 described above can be used in the above detection method to detect whether there is a conductive foreign object 300 inside the electrode hole 2103.

[0171] In an optional embodiment of the detection method, a detection device 100 is used to detect conductive foreign objects 300 within the electrode post hole 2103 of the end cap 200. The detection device 100 includes a base 10, a first conductive member 20, a second conductive member 30, and a limiting member 40. The first conductive member 20 is disposed on the base 10 and has an insertion portion. The first conductive member 20 is driven to insert the insertion portion into the sealing ring 220 and maintain a preset gap with the inner surface of the sealing ring 220. The second conductive member 30 is disposed on the base 10, and at least one of the first conductive member 20 and the second conductive member 30 is insulated from the base 10. The second conductive member 30 is used for conductive connection with the top cover plate 2101 of the end cap assembly 200, and the first conductive member 20 and the second conductive member 30 are configured to be supplied with a preset voltage. The electrode post hole 2103 of the end cap 200 is a circular hole, and both the first conductive member 20 and the second conductive member 30 are cylindrical rod structures. The limiting member 40 and the second conductive member 30 are spaced apart along the driving direction of the first conductive member 20. The first conductive member 20, the second conductive member 30, and the limiting member 40 are all driven by different driving components to achieve movement of the first conductive member 20, the second conductive member 30, and the limiting member 40 along the insertion direction X of the first conductive member 20. The second conductive member 30 and the limiting member 40 are driven by different driving components, which can jointly clamp the end cap assembly 200 and achieve electrical connection between the second conductive member 30 and the end cap assembly 200. The first conductive member 20 is driven by a driving component to achieve insertion and separation between the first conductive member 20 and the electrode hole 2103. The insertion part includes an end face and a side face, which are connected by an outwardly convex arc surface. The radius of the arc surface is R, and the value of R ranges from 1mm to 1.5mm. During the testing process, the end cap assembly 200 is first clamped and fixed using the second conductive member 30 and the limiting member 40, making the second conductive member 30 conductively connected to the top cover plate 201 of the end cap assembly 200. The first conductive member 20 is inserted into the sealing ring 220 of the end cap assembly 200, and the first conductive member 20 is positioned to abut against the electrode post 230, which is insulated from the top cover plate 2101, maintaining a preset gap between the first conductive member 20 and the inner wall of the electrode post hole 2103. The preset gap is set to a discharge distance less than or equal to a preset voltage. A preset voltage is applied to the first conductive member 20 and the second conductive member 30 to form a circuit. If the circuit is conductive, it is determined that a conductive foreign object 300 exists within the electrode post hole 2103; if the circuit is not conductive, it is determined that no conductive foreign object 300 exists within the electrode post hole 2103.Based on the circuit's resistance value being less than or equal to a preset resistance value, it is determined that a conductive foreign object 300 exists within the terminal hole 2103; based on the resistance value being greater than the preset resistance value, it is determined that there is no conductive foreign object 300 between the end cap assembly 200 and the terminal 230; and / or, based on the circuit's current value being greater than zero, it is determined that a conductive foreign object 300 exists within the terminal hole 2103; based on the current value being zero, it is determined that there is no conductive foreign object 300 between the end cap 200 and the terminal 230. The range of values ​​for R can be determined using formulas ① and ②.

[0172]

[0173] Wherein, H is the detection compensation coefficient of the preset voltage, H = 0.6 mm, A is the distance between the two points with the largest distance on the cross-section of the pole hole 2103, and the cross-section of the pole hole 2103 is perpendicular to the insertion direction X of the first conductive member 20.

[0174] The detection method of the aforementioned detection device 100 can detect both conductive foreign objects 300 that are in electrical contact with the first conductive member 20 inside the terminal hole 2103 and conductive foreign objects 300 that are not in electrical contact with the first conductive member 20 inside the terminal hole 2103. Therefore, this detection method can detect conductive foreign objects 300 that have entered the inner surface of the sealing ring 220 through the terminal hole 2103, thereby reducing the probability of short circuits occurring within the battery cell. It reduces the probability of missed detection of conductive foreign objects 300 within the terminal hole 2103 and the probability of misjudgment due to the absence of conductive foreign objects 300 within the terminal hole 2103, thus improving the success rate of detecting conductive foreign objects 300 within the terminal hole 2103. This improves the pass rate of the end cap 200 during battery cell production, thereby reducing the probability of internal short circuits in the battery cell due to manufacturing defects and improving the safety of the battery cell.

[0175] For ease of explanation, please refer to the following examples. Figures 1-6 The following description will be based on a battery production system according to some embodiments of this application.

[0176] The battery production system includes the detection method of the above embodiments, or includes the detection device 100 of the above embodiments.

[0177] Since the battery production system includes all the technical features of the detection method described in the above embodiments, or includes all the technical features of the detection device 100, the effect is the same as described above, and will not be repeated here.

[0178] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and not to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application, and they should all be covered within the scope of the claims and specification of this application. In particular, as long as there is no structural conflict, the various technical features mentioned in the embodiments can be combined in any way. This application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A method of detecting electrically conductive foreign matter within a pole hole of an end cap assembly, the method comprising: applying a voltage to the pole hole; and measuring a current through the pole hole. The method comprises the following steps: providing a first conductive member, and inserting at least part of the first conductive member into a sealing ring of the terminal cover assembly; providing a second conductive member, and electrically connecting the second conductive member with a top cover sheet of the terminal cover assembly; applying a preset voltage to the first conductive member and the second conductive member to form a circuit; in the case that the circuit is conducted, determining that there is a conductive foreign matter in the pole hole, and in the case that the circuit is not conducted, determining that there is no conductive foreign matter in the pole hole.

2. The detection method according to claim 1, characterized in that, The step of inserting at least part of the first conductive member into the sealing ring of the terminal cover assembly comprises: arranging the first conductive member to maintain a preset gap with an inner surface of the sealing ring.

3. The detection method according to claim 2, characterized in that, arranging the first conductive member to abut against a pole, and the end of the pole abutting against the first conductive member is an abutting end, the distance from the abutting end to the fitting surface between the sealing ring and the lower cover sheet of the terminal cover assembly in the insertion direction of the first conductive member is S1, the preset gap is S2, and at least one of S1 and S2 is arranged to be less than or equal to the discharge distance of the preset voltage.

4. The detection method according to claim 3, characterized in that, S2 is arranged to be less than or equal to the discharge distance of the preset voltage, and the value range of S2 is arranged to be between 0-0.2mm.

5. The detection method according to claim 4, characterized in that, The value range of S2 is arranged to be between 0.05mm-0.15mm.

6. The assay of any one of claims 1-5, wherein, The detection method further comprises: arranging the edge of the insertion end of the first conductive member into a convex circular arc surface.

7. The detection method according to claim 6, characterized in that, arranging the gap between at least part of the circular arc surface and the inner surface of the sealing ring in the radial direction of the sealing ring to be less than or equal to the discharge distance of the preset voltage.

8. The detection method according to claim 6 or 7, characterized in that, The radius of the circular arc surface is R, and the value range of R is arranged to be between 1mm-1.5mm.

9. The assay of any one of claims 1-8, wherein, The step of inserting at least part of the first conductive member into the sealing ring of the terminal cover assembly comprises: providing a positioning mechanism, and positioning the terminal cover assembly in a first direction and a second direction through the positioning mechanism, the first direction and the second direction are both perpendicular to the insertion direction of the first conductive member, and the first direction and the second direction are perpendicular.

10. The detection method according to claim 9, characterized in that, The step of inserting at least part of the first conductive member into the sealing ring of the terminal cover assembly further comprises: clamping the terminal cover assembly.

11. The assay of any one of claims 1-8, wherein, The step of determining that there is a conductive foreign matter in the pole hole in the case that the circuit is conducted, and determining that there is no conductive foreign matter in the pole hole in the case that the circuit is not conducted, comprises: in the case that the resistance value of the circuit is less than or equal to a preset resistance value, determining that there is the conductive foreign matter in the pole hole, and in the case that the resistance value is greater than the preset resistance value, determining that there is no conductive foreign matter in the pole hole; and / or, in the case that the value of the current value of the circuit is greater than zero, determining that there is the conductive foreign matter in the pole hole, and in the case that the current value is zero, determining that there is no conductive foreign matter in the pole hole.

12. A device for detecting electrically conductive foreign matter within a pole hole of an end cap assembly, the device comprising: The detection device comprises: a base; a first conductive member arranged on the base, having an insertion part, and being arranged to be driven to insert the insertion part into the pole hole and maintain a preset gap with the inner wall of the pole hole; A second conductive member is arranged on the base, at least one of the first conductive member and the second conductive member is insulated from the base, and the second conductive member is arranged to be conductively connected with a top cover sheet of the end cover assembly, and the first conductive member and the second conductive member are arranged to be connected to a preset voltage.

13. The detection device of claim 12, wherein, The insertion portion comprises an end surface and a side surface, and the end surface and the side surface are connected by an outward convex circular arc surface.

14. The detection device of claim 13, wherein, The radius of the circular arc surface is R, and the value of R is between 1 mm and 1.5 mm.

15. The detection device according to any one of claims 12-14, characterized in that, The detection device further comprises a limiting member, the limiting member is arranged along the driving direction of the first conductive member, and at least one of the limiting member and the second conductive member is driven to jointly clamp the end cover assembly.

16. The detection device of claim 15, wherein, The limiting member comprises a first limiting member and a second limiting member, the first limiting member and the second limiting member are arranged along a first direction, one of the first limiting member and the second limiting member is connected with the base, and the other of the first limiting member and the second limiting member and the second conductive member are driven to jointly clamp the end cover assembly, the second conductive member is arranged between the first limiting member and the second limiting member along the first direction, and the first direction is perpendicular to the insertion direction of the first conductive member.

17. The detection device according to any one of claims 12-16, characterized in that The first conductive member comprises a conductive rod, the insertion portion of the conductive rod has a circular or square cross-sectional profile, and the cross-sectional profile is perpendicular to the length direction of the conductive rod.

18. The detection device according to any one of claims 12-16, characterized in that The detection device further comprises a positioning mechanism, the positioning mechanism is used for positioning the end cover assembly along a first direction and a second direction, the first direction and the second direction are both perpendicular to the insertion direction of the first conductive member, and the first direction and the second direction are perpendicular.

19. The detection device of claim 18, wherein, The positioning mechanism comprises a first positioning member and a second positioning member, the first positioning member and the second positioning member are arranged on the base, the first positioning member is used for positioning the end cover assembly along a first direction, and the second positioning member is used for limiting the positioning of the end cover assembly along a second direction, Alternatively, the positioning mechanism comprises a third positioning member, the third positioning member is connected with the base, a limiting groove is arranged on the side of the third positioning member away from the base, the limiting groove is used for accommodating part of the end cover assembly to position the end cover assembly along a first direction and a second direction, The first direction and the second direction are both perpendicular to the insertion direction of the first conductive member, and the first direction and the second direction are perpendicular.

20. A battery production system, characterized by, The detection device for detecting conductive foreign matters in the pole hole of the end cover assembly of the battery monomer, the detection device is used for detecting whether the conductive foreign matters exist in the pole hole of the end cover assembly of the battery monomer.

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