End cover assembly, battery monomer, battery and electric device

Abstract

The embodiment of the utility model provides an end cover assembly, a battery monomer, a battery and an electric device. The end cover assembly is used for covering the open end of the battery shell, and comprises an electrode terminal, an adapter and an insulating part. The adapter is used for forming electric connection between the electrode terminal and a battery cell in the battery shell, and comprises at least two laminating parts and at least one bending part; wherein the at least two lamination parts are arranged in a lamination mode in the first direction, and the bending parts are connected with the adjacent edges of the two adjacent lamination parts; and the insulating part is arranged between at least part of the two adjacent laminated parts, so that after the bending part connected with the two adjacent laminated parts is broken, the two laminated parts are electrically insulated. By arranging the insulating part between the two adjacent laminated parts of the adapter, when the two adjacent laminated parts are disconnected, the insulating part can keep the two adjacent laminated parts electrically insulated, so that the probability of fire and explosion of the battery monomers is reduced, and a certain protection effect on the battery monomers is achieved.

Description

[Technical Field]

[0001] This application relates to the field of battery technology, and in particular to an end cap assembly, a battery cell, a battery, and an electrical device. [Background Technology]

[0002] Rechargeable batteries are widely used in electric vehicles, mobile devices, and power tools due to their advantages such as high energy density, high power density, high cycle life, and long storage time. However, existing battery cells are prone to catching fire and exploding under reverse high voltage conditions. [Summary of the Invention]

[0003] The main technical problem addressed by this application is to provide an end cap assembly, a battery cell, a battery, and an electrical device that can reduce the probability of battery cell fire and explosion.

[0004] In a first aspect, this application provides an end cap assembly for covering the open end of a battery casing. The end cap assembly includes: electrode terminals, an adapter, and an insulating member. The adapter is used to form an electrical connection between the electrode terminals and the battery cells within the battery casing, and includes at least two stacked portions and at least one bent portion; wherein, the at least two stacked portions are stacked along a first direction, and the bent portion connects adjacent edges of two adjacent stacked portions; the insulating member is provided between at least a portion of two adjacent stacked portions, so that after the bent portion connected to the two adjacent stacked portions breaks, the two stacked portions remain electrically insulated. By providing an insulating member between two adjacent stacked portions of the adapter, when the two adjacent stacked portions break, the insulating member can maintain electrical insulation between the two adjacent stacked portions, reducing the probability of battery cell fire and explosion, thereby providing a certain degree of protection for the battery cells.

[0005] In some embodiments, the insulating member is used to increase the spacing between the two laminated portions connected to the bend in a first direction after the bend breaks. By providing an insulating member between the two laminated portions connected to the bend, when the adapter is subjected to reverse high voltage, the spacing between the two laminated portions connected to the bend can be increased, reducing the possibility of repeated overlap between two adjacent laminated portions and lowering the probability of battery cell fire and explosion.

[0006] In some embodiments, the increase in spacing is not less than 0.1 mm in both the broken and unbroken bent portion states. This design method can improve the insulation between the two laminated portions connected to the bent portion after the bent portion breaks.

[0007] In some embodiments, the insulating member is an elastic member, and the insulating member is compressed and disposed between the two laminated portions connected to the bending portion in a state where the bending portion is not broken. This design simplifies the structure of the insulating member.

[0008] In some embodiments, in the first direction, the insulating member has a first thickness in its natural state, and in the state where the bend is not broken, the insulating member has a second thickness. The first thickness and the second thickness satisfy the following relationship: 5% < (ba) / a < 50%; where b is the first thickness and a is the second thickness. When the bend breaks, the bend is subjected to a pressure reduction in the first direction, and the insulating member within the above-mentioned compression ratio range is sufficient to cause the bend in the broken state to spring open, thereby separating the two laminated portions connected to the bend.

[0009] In some embodiments, the projected area of ​​the insulating member perpendicular to the first direction is greater than 2 square millimeters and smaller than the inner diameter cross-sectional area of ​​the battery housing. This design of the insulating member's area allows the adapter to spring open, and the method of having an area smaller than the inner diameter cross-sectional area of ​​the battery housing reduces the probability of interference between the insulating member and the inner wall of the battery housing, thus facilitating the placement of the adapter and the insulating member into the battery housing.

[0010] In some embodiments, the adapter includes a first stack, a second stack, and a third stack. The bending portion includes a first bending portion connecting the first and second stacks and a second bending portion connecting the second and third stacks. The third stack is disposed adjacent to and electrically connected to the battery cell. The electrode terminal is electrically connected to the first stack and includes a first portion located between the first and second stacks and a second portion passing through a through-hole in the first stack. This design allows for better connection between the electrode terminal and the battery cell via the adapter.

[0011] In some embodiments, the insulating element is connected to the end face of the first portion of the electrode terminal facing the second stack. This design reduces the probability of the first portion overlapping with the second stack.

[0012] In some embodiments, there are at least two electrode terminals, and an insulating element is bridged between at least two electrode terminals. This design can improve the insulation effect.

[0013] In some embodiments, the insulating member includes a sheet-like body and an annular flange. The sheet-like body is stacked and fixed on the end face of the first portion facing the second stack, and the annular flange is connected to the sheet-like body and is disposed around the peripheral side of the first portion. By enclosing the electrode terminals with the sheet-like body and the annular flange of the insulating member, the insulation between the electrode terminals and the second stack is improved.

[0014] In some embodiments, an insulating element is connected to the side of the third layer stack facing the second layer stack. This design reduces the probability of overlap between the second and third layers stack.

[0015] In some embodiments, at least a portion of the bend is configured as a fusible portion, and an insulating member is disposed between two laminated portions connected to the fusible portion, so that after the fusible portion melts, the two laminated portions connected to the fusible portion remain electrically insulated. Configuring a portion of the bend as a fusible portion and providing an insulating member between the two laminated portions connected to the fusible portion can further protect the battery cell.

[0016] In some embodiments, the insulating element is connected to adjacent laminates via an adhesive layer; alternatively, the insulating element is formed on the surface of adjacent laminates. This design allows the insulating element to be flexibly disposed between adjacent laminates.

[0017] In some embodiments, the insulating material includes at least one of fluororubber, EPDM, polytetrafluoroethylene, polypropylene, polyethylene terephthalate, polycarbonate, and polyphenylene sulfide. The material of the insulating material can be selected according to requirements.

[0018] Secondly, this application proposes a battery cell, including a battery casing, a battery cell, and an end cap assembly as described in the above embodiments. The battery casing has at least one open end; the battery cell is located inside the battery casing; the end cap assembly covers the open end, and the adapter of the end cap assembly is electrically connected to the battery cell.

[0019] Thirdly, this application proposes a battery including the battery cell described in the above embodiments.

[0020] Fourthly, this application proposes an electrical device including the battery cell described in the above embodiments.

[0021] 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 Image Description]

[0022] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the embodiments of this application will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on the drawings without creative effort.

[0023] Figure 1 This is a schematic diagram of the structure of a vehicle provided in one embodiment of this application;

[0024] Figure 2 This is an exploded view of a battery provided in one embodiment of this application;

[0025] Figure 3This is an exploded view of a single battery cell provided in an embodiment of this application;

[0026] Figure 4 This is a top view of an end cap assembly according to an embodiment of this application;

[0027] Figure 5 for Figure 4 Exploded view of one embodiment of the mid-end cover assembly;

[0028] Figure 6 for Figure 4 A cross-sectional view of one embodiment along section line AA;

[0029] Figure 7 for Figure 4 A cross-sectional view of one embodiment along the BB section line;

[0030] Figure 8 for Figure 5 A schematic diagram of one embodiment of the transfer connector;

[0031] Figure 9 for Figure 8 A top view of one embodiment of the intermediate connector in its unbent state;

[0032] Figure 10 for Figure 5 A schematic diagram of one embodiment of the middle electrode terminal;

[0033] Figure 11 for Figure 5 A schematic diagram of one embodiment after the middle electrode terminal and adapter are assembled;

[0034] Figure 12 for Figure 11 A schematic diagram of one embodiment of the middle electrode terminal and insulating component;

[0035] Figure 13 for Figure 5 A schematic diagram of another embodiment of the insulating component;

[0036] Figure 14 for Figure 4 A cross-sectional view of another embodiment along section line AA;

[0037] Figure 15 for Figure 4 A cross-sectional view of another embodiment along the BB section line;

[0038] Figure 16 This is an exploded view of another embodiment of the end cap assembly of this application.

[0039] The accompanying drawings are not drawn to scale.

[0040] Marker description: Vehicle 1;

[0041] Battery 100, controller 200, motor 300;

[0042] Battery cell 20, first part 11, second part 12, casing 10, battery housing 21, battery cell 22, end cap assembly 23;

[0043] Riveting block 31, upper plastic 32, end cap 33, sealing ring 34, lower plastic 35, electrode terminal 36, first part 51, second part 52, insulating part 37, adapter part 38;

[0044] Stacked portion 41, first stacked portion 411, second stacked portion 412, third stacked portion 413, through hole 414, bent portion 42, first bent portion 421, second bent portion 422;

[0045] Sheet-shaped main body 61, annular flange 62; first direction X.

Detailed Implementation Methods

[0046] The embodiments of this application will be described in further detail below with reference to the accompanying drawings and examples. The detailed description of the following embodiments and the accompanying drawings are used to illustrate the principles of this application by way of example, but should not be used to limit the scope of this application, that is, this application is not limited to the described embodiments.

[0047] In the description of this application, it should be noted that, unless otherwise stated, "a plurality of" means two or more; the terms "upper," "lower," "left," "right," "inner," and "outer," etc., indicating orientation or positional relationships, are only for the convenience of describing 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, and therefore should not be construed as a limitation on this application. Furthermore, the terms "first," "second," and "third," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance. "Vertical" is not vertical in the strict sense, but within the allowable tolerance range. "Parallel" is not parallel in the strict sense, but within the allowable tolerance range.

[0048] The directional terms used in the following description refer to the directions shown in the figures and are not intended to limit the specific structure of this application. It should also be noted in the description of this application that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0049] Currently, judging from market trends, the application of power batteries is becoming increasingly widespread. Power batteries are not only used in energy storage systems such as hydropower, thermal power, wind power, and solar power plants, but also extensively used in electric vehicles such as electric bicycles, electric motorcycles, and electric cars, as well as in military equipment and aerospace. With the continuous expansion of power battery applications, market demand is also constantly increasing.

[0050] The inventors of this application have noted that in battery cells, adapters are generally used to electrically connect the cell and electrode terminals. During use, these adapters are bent into a stacked structure. When the current in a battery cell becomes excessive under abnormal conditions, high voltage is applied to the positive and negative electrodes in reverse. The adapter attempts to cut off the current by melting. However, at this time, the cell will bear the reverse high voltage of the system. After melting, there is a reverse high voltage interface between adjacent stacked parts of the adapter. This reverse high voltage interface causes the disconnected adapter layers to overlap repeatedly and remain conductive for a long time, ultimately leading to the battery cell catching fire and exploding.

[0051] To address the aforementioned problems, the inventors of this application discovered that an insulating component can be designed. Specifically, an insulating component is provided between adjacent laminated portions of the adapter. When the adapter melts, the insulating component can separate the disconnected laminated portions through an insulating layer, thereby insulating the reverse high-voltage interfaces between adjacent laminated portions and reducing the probability of the battery cell catching fire and exploding after being subjected to reverse high voltage.

[0052] Through further in-depth research, the inventors also designed an elastic insulating component. When the adapter melts, the elastic insulating component springs open to separate adjacent layers, thus insulating the reverse high-voltage interfaces between adjacent layers, reducing the possibility of repeated overlap between the adapter layers, and lowering the probability of battery cell fires and explosions.

[0053] The battery cells disclosed in this application can be used in electrical devices that use batteries as a power source or in various energy storage systems that use batteries as energy storage elements. Electrical devices can be, but are not limited to, mobile phones, tablets, laptops, electric toys, power tools, electric vehicles, electric cars, ships, spacecraft, etc. Electric toys can include stationary or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, etc. Spacecraft can include airplanes, rockets, space shuttles, and spacecraft, etc.

[0054] For ease of explanation, the following embodiments will be described using a vehicle 1 as an example of an electrical device according to an embodiment of this application.

[0055] Please refer to Figure 1 , Figure 1This is a schematic diagram of the structure of a vehicle 1 provided in some embodiments of this application. Vehicle 1 can be a gasoline-powered vehicle, a natural gas-powered vehicle, or a new energy vehicle. The new energy vehicle can be a pure electric vehicle, a hybrid electric vehicle, or a range-extended electric vehicle, etc. A battery 100 is installed inside the vehicle 1, and the battery 100 can be located at the bottom, front, or rear of the vehicle 1. The battery 100 can be used to power the vehicle 1; for example, the battery 100 can serve as the operating power source for the vehicle 1. The vehicle 1 may also include a controller 200 and a motor 300. The controller 200 is used to control the battery 100 to supply power to the motor 300, for example, to meet the power needs of the vehicle 1 during starting, navigation, and driving.

[0056] In some embodiments of this application, the battery 100 can not only serve as the operating power source for the vehicle 1, but also as the driving power source for the vehicle 1, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1.

[0057] Please refer to Figure 2 , Figure 2 This is an exploded view of a battery 100 provided in some embodiments of this application. The battery 100 includes a housing 10 and a battery cell 20, with the battery cell 20 housed within the housing 10. The housing 10 provides a space for the battery cell 20 and can have various structures. In some embodiments, the housing 10 may include a first portion 11 and a second portion 12, which overlap each other, jointly defining a space for accommodating the battery cell 20. The second portion 12 may be a hollow structure with one open end, and the first portion 11 may be a plate-like structure, covering the open side of the second portion 12 so that the first portion 11 and the second portion 12 jointly define the space; alternatively, the first portion 11 and the second portion 12 may both be hollow structures with one open side, with the open side of the first portion 11 covering the open side of the second portion 12. Of course, the housing 10 formed by the first portion 11 and the second portion 12 can have various shapes, such as a cylinder, a cuboid, etc.

[0058] In battery 100, there can be multiple battery cells 20, which can be connected in series, parallel, or in a mixed manner. A mixed connection means that multiple battery cells 20 are connected in both series and parallel configurations. Multiple battery cells 20 can be directly connected in series, parallel, or in a mixed manner, and then the entire assembly of the multiple battery cells 20 is housed within the housing 10. Alternatively, battery 100 can also be composed of multiple battery cells 20 first connected in series, parallel, or in a mixed manner to form a battery module, and then multiple battery modules are connected in series, parallel, or in a mixed manner to form a whole, which is also housed within the housing 10. Battery 100 may also include other structures; for example, it may include a busbar component for electrical connection between the multiple battery cells 20.

[0059] Each battery cell 20 can be a secondary battery or a primary battery; it can also be a lithium-sulfur battery, a sodium-ion battery, or a magnesium-ion battery, but is not limited to these. The battery cell 20 can be cylindrical, flat, cuboid, or other shapes.

[0060] Please refer to Figure 3 , Figure 3 This is an exploded view of a battery cell 20 provided in some embodiments of this application. The battery cell 20 refers to the smallest unit that makes up the battery 100. For example... Figure 3 The battery cell 20 includes an end cap assembly 23, a battery casing 21, a cell 22, and other functional components.

[0061] End cap assembly 23 refers to a component that covers the opening of battery housing 21 to isolate the internal environment of battery cell 20 from the external environment. The shape of end cap assembly 23 can be adapted to the shape of battery housing 21 to fit the battery housing 21. Optionally, end cap assembly 23 can be made of a material with certain hardness and strength (such as aluminum alloy), so that end cap assembly 23 is not easily deformed under pressure and impact, allowing battery cell 20 to have higher structural strength and improved safety performance. Functional components such as electrode terminals 36 can be provided on end cap assembly 23. Electrode terminals 36 can be used for electrical connection with battery cell 22 to output or input electrical energy to battery cell 20. In some embodiments, end cap assembly 23 can also be provided with a pressure relief mechanism for releasing internal pressure when the internal pressure or temperature of battery cell 20 reaches a threshold. The material of end cap assembly 23 can also be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and this application embodiment does not impose special limitations on this.

[0062] The battery housing 21 is an assembly used to cooperate with the end cap assembly 23 to form the internal environment of the battery cell 20. This internal environment can accommodate the battery cell 22, electrolyte, and other components. The battery housing 21 and the end cap assembly 23 can be independent components, with an opening in the axial direction of the battery housing 21. The end cap assembly 23 closes the opening to form the internal environment of the battery cell 20. Alternatively, the end cap assembly 23 and the battery housing 21 can be integrated. Specifically, the end cap assembly 23 and the battery housing 21 can form a common connecting surface before other components are inserted into the housing. When it is necessary to encapsulate the interior of the battery housing 21, the end cap assembly 23 closes the battery housing 21. The battery housing 21 can have various shapes and sizes, such as cuboid, cylindrical, or hexagonal prism. Specifically, the shape of the battery housing 21 can be determined according to the specific shape and size of the battery cell 22. The battery casing 21 can be made of various materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc. This application embodiment does not impose any special restrictions on this.

[0063] The battery cell 22 is the component in the battery cell 20 where the electrochemical reaction occurs. The battery casing 21 may contain one or more battery cells 22. The battery cell 22 is mainly formed by winding or stacking positive and negative electrode plates, and typically a separator is provided between the positive and negative electrode plates. The portions of the positive and negative electrode plates containing active material constitute the main body of the battery cell 22, while the portions of the positive and negative electrode plates without active material each constitute a tab. The tabs are electrically connected to the electrode terminals 36 of the end cap assembly 23. The positive and negative tabs may be located together at one end of the main body or separately at both ends of the main body. During the charging and discharging process of the battery 100, the positive and negative active materials react with the electrolyte, and the tabs connect to the electrode terminals 36 to form a current loop.

[0064] According to some embodiments of this application, please refer to Figures 4 to 8 , Figure 4 This is a top view of an end cap assembly 23 according to an embodiment of this application; Figure 5 for Figure 4 An exploded view of one embodiment of the end cap assembly 23 in this application. Figure 6 for Figure 4 A cross-sectional view of one embodiment along section line AA; Figure 7 for Figure 4 A cross-sectional view along section line BB of one embodiment. Figure 8 for Figure 5 A schematic diagram of one embodiment of the adapter 38. This application provides an end cap assembly 23. The end cap assembly 23 is used to cover the open end of the battery casing 21. The end cap assembly 23 includes electrode terminals 36, an adapter 38, and an insulating member 37. The adapter 38 is used to form an electrical connection between the electrode terminals 36 and the battery cells 22 within the battery casing 21. Figures 5-8 As shown, the adapter 38 includes at least two stacked portions 41 and at least one bent portion 42; wherein, the at least two stacked portions 41 are stacked along a first direction X, and the bent portion 42 connects adjacent edges of two adjacent stacked portions 41; as Figure 6 and Figure 7 As shown, an insulating member 37 is provided between at least two adjacent stacked portions 41 so that the two stacked portions 41 remain electrically insulated from each other after the bent portion 42 connected to the two adjacent stacked portions 41 breaks.

[0065] Optionally, in this application, the number of electrode terminals 36 can be set according to actual conditions. In the illustrated embodiment, the number of electrode terminals 36 is two; in other embodiments, the number of electrode terminals 36 can be one or more.

[0066] Alternatively, such as Figure 9 As shown, Figure 9for Figure 8 A top view of one embodiment of the adapter 38 in its unbent state. Before assembling the end cap assembly 23, the adapter 38 is entirely sheet-like and is typically made of a soft material to facilitate bending. When assembling the end cap assembly 23, it can be... Figure 9 The adapter 38 in the middle is bent to form at least Figure 8 It contains two stacked portions 41 and one bent portion 42.

[0067] The number of bends in adapter 38 can be selected according to actual needs. When adapter 38 is bent once, two stacked portions 41 and one bent portion 42 are formed. When adapter 38 is bent multiple times, more than two stacked portions 41 and more than one bent portion 42 are formed. In one application scenario, such as... Figure 8 As shown, after bending, the adapter 38 forms three stacked portions 41 and two bent portions 42. Of course, in other application scenarios, the adapter 38 can also form more stacked portions 41 and more bent portions 42 after bending.

[0068] In one implementation, such as Figure 5 As shown, the end cap assembly 23 also includes a riveting block 31, an upper plastic 32, an end cap sheet 33, a sealing ring 34, and a lower plastic 35. The end cap sheet 33 and the lower plastic 35 interlock to press against the sealing ring 34. The sealing ring 34 is used to seal the through hole 414 to reduce the entry of external moisture into the battery cell 20. The riveting block 31 and the upper plastic 32 are used to fix the electrode terminals 36. The electrode terminals 36 pass sequentially through the adapter 38, the lower plastic 35, the sealing ring 34, the end cap sheet 33, the upper plastic 32, and the riveting block 31 to form a complete end cap assembly 23 for the battery cell 20.

[0069] The purpose of the aforementioned insulating element 37 is to maintain electrical insulation between two objects on either side of it. For example... Figure 6 and Figure 7 As shown, when the battery cell 20 is subjected to reverse high voltage, two adjacent disconnected laminated portions 41 can be separated by the insulating member 37, thereby reducing the risk of short circuit in the battery cell 20. For example, the insulating member 37 can be an insulating patch, insulating gasket, etc., and is not limited here. The material of the insulating member 37 can be plastic, rubber, etc., and is not limited here.

[0070] In summary, in the above technical solution, by providing an insulating member 37 between two adjacent stacked portions 41 of the adapter 38, when the two adjacent stacked portions 41 are disconnected, the insulating member 37 can maintain electrical insulation between the two adjacent stacked portions 41, reduce the risk of fire and explosion of the battery cell 20, and thus provide a certain degree of protection for the battery cell 20.

[0071] According to some embodiments of this application, such as Figure 6As shown, the insulating member 37 is used to increase the distance between the two laminated portions 41 connected to the bent portion 42 in the first direction X after the bent portion 42 breaks (e.g., after melting).

[0072] In one embodiment, the insulating element 37 can be an elastic element. When the bent portion 42 is in an unbroken state, the elastic element is compressed and disposed between the two stacked portions 41 connected to the bent portion 42, i.e., the elastic element is in a compressed state at this time; when the bent portion 42 breaks, the elastic force of the elastic element can act along the first direction X, increasing the distance between the two stacked portions 41 connected to the bent portion 42. The structural design of this insulating element 37 is relatively simple, easy to obtain in actual use, and easy to manufacture.

[0073] In one embodiment, the insulating member 37 can be a thermally expandable member. When the bent portion 42 is in an unbroken state, the thermally expandable member is in a normal state; when the bent portion 42 breaks, for example, after a reverse high-voltage meltdown, it releases a certain amount of heat, and the thermally expandable member increases in volume after being heated, especially its dimension along the first direction X, thereby increasing the distance between the two stacked portions 41 connected to the bent portion 42. The structural design of this insulating member 37 is relatively simple.

[0074] In summary, by providing an insulating element 37 between the two stacked portions 41 connected to the bending portion 42, when the bending portion 42 breaks, for example, after the reverse high voltage fuse is blown, the distance between the two stacked portions 41 connected to the bending portion 42 can be increased, reducing the possibility of repeated overlap between two adjacent stacked portions 41 and lowering the probability of the battery cell 20 catching fire and exploding.

[0075] According to some embodiments of this application, optionally, the increase in spacing is not less than 0.1 mm when the bent portion 42 is broken and when the bent portion 42 is not broken. For example, the increase in spacing is 0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm, etc. This arrangement can improve the insulation between the two laminated portions 41 connected to the bent portion 42 after the bent portion 42 breaks.

[0076] According to some embodiments of this application, optionally, please refer to... Figure 7When the insulating member 37 is an elastic member, in the first direction X, the insulating member 37 has a first thickness in its natural state and a second thickness in the state where the bent portion 42 is not broken. The first thickness and the second thickness satisfy the following relationship: 5% < (ba) / a < 50%; where b is the first thickness (not shown in the figure) and a is the second thickness. For example, the value of (ba) / a is 15%, 25%, 35%, 45%, etc. Specifically, the natural state refers to the natural state of the insulating member 37 before it is installed in the adapter 38, that is, the state where the insulating member 37 is not compressed. Or, the natural state refers to the state where the insulating member 37 is disassembled from the adapter 38 after compression. That is, the first thickness refers to the thickness of the insulating member 37 before it is installed or the thickness after it is disassembled after compression. The second thickness refers to the thickness of the insulating member 37 when it is compressed when it is assembled between the two stacked portions 41. In some embodiments, it is also the distance between the two stacked portions 41 connected to the bent portion 42 when they are not broken.

[0077] The compression ratio range of the insulating member 37 is 5% < (ba) / a < 50%. When the bent portion 42 breaks, the pressure on the bent portion 42 in the first direction X decreases. The insulating member 37 with the above compression ratio range is sufficient to make the bent portion 42 in the broken state spring open, so as to separate the two stacked portions 41 connected to the bent portion 42. Moreover, the above-mentioned design with a compression ratio of less than 50% can reduce the probability of the insulating member 37 being damaged by overpressure.

[0078] According to some embodiments of this application, optionally, the projected area of ​​the insulating member 37 in the direction perpendicular to the first direction X is greater than 2 square millimeters and smaller than the cross-sectional area of ​​the inner diameter of the battery casing 21.

[0079] Specifically, the projected area of ​​the insulating member 37 in the direction perpendicular to the first direction X is related to the compression amount of the insulating member 37. When the projected area of ​​the insulating member 37 in the direction perpendicular to the first direction X is greater than 2 square millimeters, it can be considered as the minimum area that allows the adapter 38 to spring open when the compression amount of the insulating member 37 is 5%. The projected area of ​​the insulating member 37 in the direction perpendicular to the first direction X is smaller than the cross-sectional area of ​​the battery housing 21, which can reduce the probability of interference between the insulating member 37 and the inner wall of the battery housing 21, making it easier to put the adapter 38 and the insulating member 37 into the battery housing 21.

[0080] According to some embodiments of this application, alternatively, please also refer to... Figure 7 , Figure 8 , Figure 10 as well as Figure 11 , Figure 10 for Figure 5 A schematic diagram of one embodiment of the middle electrode terminal 36. Figure 11 for Figure 5A schematic diagram of one embodiment after the middle electrode terminal 36 and the adapter 38 are assembled. The adapter 38 includes a first stacked portion 411, a second stacked portion 412, and a third stacked portion 413. The bending portion 42 includes a first bending portion 421 connecting the first stacked portion 411 and the second stacked portion 412, and a second bending portion 422 connecting the second stacked portion 412 and the third stacked portion 413. The third stacked portion 413 is disposed adjacent to the battery cell 22 and is electrically connected to it. The electrode terminal 36 is electrically connected to the first stacked portion 411 and includes a first portion 51 located between the first stacked portion 411 and the second stacked portion 412, and a second portion 52 passing through the through hole 414 of the first stacked portion 411.

[0081] Specifically, before bending, the adapter 38 is generally plate-shaped and has a relatively large length, such as Figure 9 As shown, the first stacked portion 411, the second stacked portion 412, the third stacked portion 413, the first bending portion 421, and the second bending portion 422 are all integral thin sheet structures, and are all part of the adapter 38.

[0082] Furthermore, such as Figure 8 and Figure 11 As shown, the first stacked portion 411 closest to the electrode terminal 36 is provided with a through hole 414, and the third stacked portion 413 is connected to the battery casing 21 (as shown). Figure 3 The battery cell 22 (as shown) is located inside the battery cell 22. Figure 3 (As shown) Connection. Electrode terminal 36 is placed between the two stacked portions 41 and passes through through hole 414. Adapter 38 is located between electrode terminal 36 and cell 22. Adapter 38 is used to form an electrical connection between electrode terminal 36 and cell 22 within battery housing 21. In one application scenario, when... Figure 9 When the adapter 38 is assembled with other components to form the end cap assembly 23, after the third stack 413 is connected to the cell 22, the second bending portion 422 is bent so that the second stack 412 is parallel to the third stack 413; then the first bending portion 421 is bent so that the second part 52 of the electrode terminal 36 passes through the through hole 414, and the first part 51 of the electrode terminal 36 is located between the first stack 411 and the second stack 412, and finally as follows. Figure 11 As shown, the adapter 38 is bent and placed inside the end cap assembly 23. By bending the adapter 38, the space occupied by the adapter 38 can be reduced, which facilitates the connection between the end cap assembly 23 and the battery housing 21.

[0083] like Figure 10 As shown, electrode terminal 36 is a T-shaped column. The upper half of the T-shape is the first part 51 of electrode terminal 36, and the lower half of the T-shape is the second part 52 of electrode terminal 36. Electrode terminal 36 is used in an upside-down configuration. Figure 11As shown, a through hole 414 is provided on the first stacked portion 411. The second part 52 of the electrode terminal 36 passes through the through hole 414 of the first stacked portion 411. The first part 51 of the electrode terminal 36 is located between the first stacked portion 411 and the second stacked portion 412 and can be moved by the electrode terminal 36. The third stacked portion 413 is electrically connected to the battery cell 22 on the side opposite to the first stacked portion 411.

[0084] In another embodiment, the adapter 38 includes a first stacked portion 411, a second stacked portion 412, and a third stacked portion 413. The bending portion 42 includes a first bending portion 421 connecting the first stacked portion 411 and the second stacked portion 412, and a second bending portion 422 connecting the second stacked portion 412 and the third stacked portion 413. The third stacked portion 413 is disposed adjacent to the battery cell 22 on the side facing away from the first stacked portion 411 and is electrically connected to it. The first stacked portion 411 is disposed adjacent to the electrode terminal 36 on the side facing away from the third stacked portion 413 and is electrically connected to it. That is, the first stacked portion 411 does not have a through hole 414, and the surface of the first stacked portion 411 is directly soldered to the electrode terminal 36.

[0085] An adapter 38 is provided between the electrode terminal 36 and the cell 22. This design allows for a better connection between the electrode terminal 36 and the cell 22 via the adapter 38. When the current of the battery 100 is too high, the current can be cut off by disconnecting the adapter 38.

[0086] According to some embodiments of this application, optionally, please refer to... Figure 11 and Figure 12 , Figure 12 for Figure 11 A schematic diagram of one embodiment of the middle electrode terminal 36 and the insulating member 37. The insulating member 37 is connected to the end face of the first portion 51 of the electrode terminal 36 facing the second stacked portion 412.

[0087] Specifically, when the first bend 421 breaks, an insulating member 37 can be provided between the first stacked portion 411 and the second stacked portion 412. Since the electrode terminal 36 passes through the first stacked portion 411, the insulating member 37 should be provided between the bottom of the electrode terminal 36 and the second stacked portion 412.

[0088] By placing the insulating element 37 at the bottom of the electrode terminal 36, the probability of the first part 51 overlapping with the second layer 412 is reduced.

[0089] According to some embodiments of this application, optionally, such as Figure 12 As shown, there are at least two electrode terminals 36, and an insulating member 37 is bridged between at least two electrode terminals 36.

[0090] Specifically, such as Figure 12As shown, the insulating element 13 is sheet-shaped, consisting only of the sheet-shaped main body 61, and the entire insulating element 37 (i.e., the sheet-shaped main body 61) is located at the bottom of the electrode terminal 36. When there are two electrode terminals 36, the entire insulating element 37 is located at the bottom of both electrode terminals 36. This can improve the insulation effect.

[0091] According to some embodiments of this application, optionally, please refer to... Figure 13 , Figure 13 for Figure 5 A schematic diagram of another embodiment of the insulating member 37. The insulating member 37 includes a sheet-like body 61 and an annular flange 62. The sheet-like body 61 is stacked and fixed on the end face of the first part 51 facing the second layer 412. The annular flange 62 is connected to the sheet-like body 61 and is disposed around the peripheral side surface of the first part 51.

[0092] Specifically, when the electrode terminal 36 passes through the first stack 411, the first portion 51 is located between the first stack 411 and the second stack 412. At this time, the sheet-like body 61 of the insulating member 37 is fixed to the end face of the first portion 51 facing the second stack 412. The second portion 52 of the electrode terminal 36, which passes through the protruding portion of the first stack 411, is wrapped by the annular flange 62 of the insulating member 37.

[0093] The electrode terminal 36 is enclosed by the sheet-like body 61 and the annular flange 62 of the insulating member 37, which improves the insulation of the electrode terminal 36.

[0094] According to some embodiments of this application, optionally, please refer to... Figure 7 and Figure 11 An insulating element 37 is connected to the side of the third layer 413 facing the second layer 412.

[0095] When the second bend 422 breaks, the insulating member 37 can be disposed between the third stack 413 and the second stack 412. This design can reduce the probability of the second stack 412 and the third stack 413 overlapping.

[0096] When the first bend 421 breaks, the insulating member 37 is disposed between the first stacked portion 411 and the second stacked portion 412. When the second bend 422 breaks, the insulating member 37 is disposed between the second stacked portion 412 and the third stacked portion 413. Alternatively, when both the first bend 421 and the second bend 422 break, the insulating member 37 may be disposed between the first stacked portion 411 and the second stacked portion 412 and between the second stacked portion 412 and the third stacked portion 413.

[0097] According to some embodiments of this application, optionally, please refer to... Figure 7 and Figure 11At least part of the bent portion 42 is configured as a fusible portion (not shown in the figure), and an insulating member 37 is disposed between the two laminated portions 41 connected to the fusible portion, so that after the fusible portion melts, the two laminated portions 41 connected to the fusible portion remain electrically insulated.

[0098] Specifically, a fuse is provided at the bending portion 42, which can be melted by a large current when a reverse high voltage is applied to the battery cell 20. Therefore, the fuse can have an unmelted state (i.e., during normal operation) or a melted state (i.e., after an operation such as the breakage or melting of the fuse is activated).

[0099] Optionally, at least a portion of the bend 42 may be configured as a fusible portion, meaning that the fusible portion is formed in a portion of the bend 42 of the adapter 38. The cross-section of the portion of the bend 42 with the fusible portion may be smaller than the cross-section of the other portions of the bend 42 without the fusible portion. Alternatively, some holes may be provided in the bend 42, and the bend 42 around the holes may form a fusible portion.

[0100] When a reverse high voltage is applied to the battery cell 20, for example, when the fuse portion changes from a never-fused state to a fused state, the fuse portion, whose cross-section is smaller than that of other parts of the bent portion 42, can be melted by the current. In this way, the fuse portion can be activated and the current flow in the battery cell 20 can be stopped.

[0101] In the multiple bends 42 of the adapter 38, only one bend 42 may be configured as a fusible link; alternatively, multiple bends 42 (e.g., all bends 42) may be configured as fusible links, depending on the specific circumstances. For example, a fusible link may be provided in the bend 42 of the adapter 38 near the cell 22, or it may be provided in the bend 42 of the adapter 38 near the electrode terminal 36. Only one insulating member 37 needs to be provided in the two stacked portions 41 connected to the fusible link; it is not necessary to provide an insulating member 37 in every bend 42.

[0102] In summary, by constructing a partial bend 42 as a fusible section and providing an insulating member 37 between the two stacked sections 41 connected to the fusible section, the battery cell 20 can be further protected.

[0103] According to some embodiments of this application, optionally, the insulating element 37 is connected to the adjacent laminate 41 by an adhesive layer; or, the insulating element 37 is formed on the surface of the adjacent laminate 41.

[0104] Specifically, the insulating element 37 can be provided between the two laminated portions 41 connected to the fusible layer through an adhesive layer, or the insulating element 37 can be directly formed on the surface of the two laminated portions 41 connected to the fusible layer by spraying or injection molding. The insulating element 37 can be flexibly disposed between adjacent laminated portions 41.

[0105] According to some embodiments of this application, optionally, the material of the insulating element 37 includes at least one of fluororubber, EPDM, polytetrafluoroethylene, polypropylene, polyethylene terephthalate, polycarbonate, and polyphenyl sulfide.

[0106] When the insulating component 37 is an elastic component, its material can be rubber, plastic, etc., and is not limited here. When the insulating component 37 is made of rubber, it can be fluororubber (FKM or FPM), ethylene propylene diene monomer (EPDM), etc., and is not limited here. When the insulating component 37 is made of plastic, it can be polytetrafluoroethylene (PFA), polypropylene (PP), etc., and is not limited here.

[0107] When the insulating component 37 is non-elastic, its material can be polyethylene terephthalate (PET), polycarbonate (PC), polyphenylene sulfide (PPS), etc., and there is no limitation here. In actual use, the material of the insulating component 37 can be selected according to the requirements.

[0108] Furthermore, when the insulating element 37 is inelastic, in order to improve the insulation effect, the area of ​​the insulating element 37 must be at least larger than the smallest area of ​​the two adjacent laminated portions 41. For example, as Figure 4 , Figure 8 and Figure 9 As shown, when the insulating member 37 is provided between the first stacked portion 411 and the second stacked portion 412, the outer edge of the insulating member 37 coincides with the outer edge of the first stacked portion 411 of the adapter 38; when the insulating member 37 is provided between the second stacked portion 412 and the third stacked portion 413, the outer edge of the insulating member 37 coincides with the outer edge of the third stacked portion 413.

[0109] When the insulating element 37 is elastic, the area of ​​the insulating element 37 does not necessarily have to be larger than the smallest area of ​​the two adjacent laminated portions 41. For example... Figure 14 , Figure 15 and Figure 16 As shown, Figure 14 for Figure 4 A cross-sectional view of another embodiment along section line AA. Figure 15 for Figure 4 A cross-sectional view of another embodiment along the BB section line; Figure 16 This is an exploded view of another embodiment of the end cap assembly 23 of this application. It is sufficient that the insulating member 37 allows the laminated portions 41 on both sides to spring open when the fused portion melts.

[0110] Finally, in a specific application scenario, such as Figure 4As shown, the end cap assembly 23 includes electrode terminals 36, an adapter 38, and an insulator 37. The adapter 38 is bent and disposed within the end cap assembly 23. One laminated portion 41 of the adapter 38 is connected to the battery cell 22. A through hole 414 is provided on one laminated portion 41 near the electrode terminal 36. The electrode terminal 36 is placed between two laminated portions 41 and passes through the through hole 414, enabling electrical connection between the electrode terminal 36 and the battery cell 22 via the adapter 38. A fusible link is constructed at the bent portion 42, and the insulator 37 is disposed between the two laminated portions 41 connected to the fusible link. When the fusible link is melted by a large current, the bent portions 42 connecting the two adjacent laminated portions 41 are broken, and the insulator 37 maintains electrical insulation between the two laminated portions 41. This protects the battery cell 20 and reduces the probability of the battery cell 20 catching fire or exploding.

[0111] Although this application has been described with reference to preferred embodiments, various modifications can be made thereto and components can be replaced with equivalents without departing from the scope of this application. In particular, the technical features mentioned in the various embodiments can be combined in any manner, provided there is no structural conflict. 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. An end cap assembly for covering an open end of a battery casing, characterized in that, The end cover assembly comprises: an electrode terminal; an adapter for forming an electrical connection between the electrode terminal and an electric cell in the battery shell, comprising at least two stacked portions and at least one bending portion; wherein the at least two stacked portions are arranged in a first direction, and the bending portion connects adjacent edges of two adjacent stacked portions; an insulating member arranged between at least two adjacent stacked portions to maintain electrical insulation between the two stacked portions after the bending portion is broken; the insulating member is also used to increase the spacing between the two stacked portions connected by the bending portion after the bending portion is broken.

2. The end cover assembly of claim 1, wherein, the increase in spacing is not less than 0.1 mm in the state of the broken bending portion and the state of the unbroken bending portion.

3. The end cover assembly of any one of claims 1-2, wherein, the insulating member is a resilient member, and the insulating member is arranged between the two stacked portions connected by the bending portion in a compressed state in the state of the unbroken bending portion.

4. The end cover assembly of any one of claims 1-3, wherein, in the first direction, the insulating member has a first thickness in a natural state, and a second thickness in the state of the unbroken bending portion, and the first thickness and the second thickness satisfy the following relationship: 5% < (b-a) / a < 50%; wherein b is the first thickness, and a is the second thickness.

5. The end cover assembly of any one of claims 1-4, wherein, the projection area of the insulating member in a direction perpendicular to the first direction is greater than 2 square millimeters and less than the cross-sectional area of the inner diameter of the battery shell.

6. The end cover assembly of any one of claims 1-5, wherein, the adapter comprises a first stacked portion, a second stacked portion, and a third stacked portion, and the bending portion comprises a first bending portion connecting the first stacked portion and the second stacked portion, and a second bending portion connecting the second stacked portion and the third stacked portion; wherein the third stacked portion is arranged adjacent to the electric cell and is electrically connected to each other; the electrode terminal is electrically connected to the first stacked portion, and comprises a first part between the first stacked portion and the second stacked portion, and a second part passing through a through hole in the first stacked portion.

7. The end cover assembly of claim 6, wherein, the insulating member is connected to an end surface of the first part of the electrode terminal facing the second stacked portion.

8. The end cover assembly of claim 7, wherein, the number of electrode terminals is at least two, and the insulating member is bridged between the at least two electrode terminals.

9. The end cover assembly of claim 6, wherein, the insulating member comprises a sheet-shaped body and an annular flange, the sheet-shaped body is fixed on the end surface of the first part facing the second stacked portion, and the annular flange is connected to the sheet-shaped body and arranged around the peripheral surface of the first part.

10. The end cover assembly of claim 6, wherein, The third layer is connected to the second layer by the insulating member.

11. The end cap assembly of any one of claims 1-10, wherein, At least a portion of the bent portion is configured as a fuse portion, and the insulating member is disposed between two of the layers connected to the fuse portion, such that after the fuse portion is fused, the two layers connected to the fuse portion are electrically insulated.

12. The end cap assembly of any one of claims 1-11, wherein, The insulating member is connected to the adjacent layers by an adhesive layer, or the insulating member is formed on the surface of the adjacent layers.

13. The end cap assembly of any one of claims 1-12, wherein, The insulating member is made of at least one of fluoroelastomer, ethylene propylene diene rubber, polytetrafluoroethylene, polypropylene, polyethylene terephthalate, polycarbonate, and polyphenylene sulfide.

14. A battery cell, characterized by Comprising: a battery housing having at least one open end; a battery cell located in the battery housing; the end cap assembly of any one of claims 1-13, wherein the end cap assembly covers the open end, and the adapter of the end cap assembly is electrically connected to the battery cell.

15. A battery, characterized by A battery cell as claimed in claim 14.

16. An electrical device, comprising: A battery cell as claimed in claim 14.

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