Top cover assembly, battery, battery pack and electric device

Abstract

The utility model provides a kind of top cover assembly, battery, battery pack and electric equipment, top cover assembly includes top cover and connecting piece, top cover includes inner surface and outer surface, inner surface is used to towards battery cell, outer surface and inner surface are oppositely arranged;Connecting piece is integrally formed structure, connecting piece includes oppositely arranged first end and second end, connecting piece is worn in top cover, first end is located in the side of the inner surface of top cover, to be used for and battery cell electric connection, second end is located in the side of the outer surface of top cover, and second end is provided with fuse structure.In the embodiment of the utility model, by being provided with fuse structure on connecting piece, fuse structure will first melt due to local resistance heating or material softening when battery appears thermal runaway, actively cut off battery loop, to block continuous discharge and energy input and output, block the generation of heat.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, specifically to a top cover assembly, a battery, a battery pack, and an electrical device. Background Technology

[0002] A battery typically consists of a casing, a core, and a top cover assembly. The core is housed within the casing, and the top cover assembly is connected to the casing to seal it. The top cover assembly is also electrically connected to the core to output electrical energy.

[0003] In related technologies, when a battery experiences thermal runaway, the current increases sharply, leading to a rise in temperature, which can easily cause the battery to burn or explode. Utility Model Content

[0004] The present invention provides a top cover assembly that can improve the technical problem in the related art where thermal runaway of a battery can easily lead to battery combustion.

[0005] In a first aspect, embodiments of the present invention provide a top cover assembly, comprising:

[0006] A top cover, the top cover including an inner surface and an outer surface, the inner surface being oriented toward the battery cell, and the outer surface being disposed opposite to the inner surface;

[0007] The connector is an integrally formed structure. The connector includes a first end and a second end arranged opposite to each other. The connector passes through the top cover. The first end is located on the inner surface of the top cover for electrical connection with the battery cell. The second end is located on the outer surface of the top cover and is provided with a fusible structure.

[0008] In one embodiment, the second end is further provided with a welding portion, which is used to weld with an external device to form an electrical connection;

[0009] The fusion structure is located at the portion of the second end between the welded portion and the outer surface.

[0010] In one embodiment, the connector includes:

[0011] A terminal section, the terminal section passing through the top cover, such that the end of the terminal section near the battery cell forms the first end; and,

[0012] A connecting segment, which is bent and connected to the pole segment to form the second end, wherein the fusible structure is located on the side of the connecting segment closer to the pole segment.

[0013] In one embodiment, the fusion structure includes a fusion groove.

[0014] In one embodiment, the fuse groove extends along the width direction of the second end, and the width of the fuse groove is equal to the width of the second end; and / or,

[0015] The cross-sectional area of ​​the portion of the second end located on the bottom wall of the fuse groove is greater than or equal to 4 square millimeters and less than or equal to 8 square millimeters.

[0016] In one embodiment, the top cover assembly further includes a fixing block disposed on the outer surface, and the second end is riveted or welded to the fixing block.

[0017] In one embodiment, the top cover assembly further includes a seal, the connector includes a support portion that protrudes from the outer peripheral side of the first end, and at least a portion of the seal is sandwiched between the inner surface and the support portion.

[0018] In one embodiment, the support portion is disposed around the first end.

[0019] In one embodiment, the side of the support portion opposite to the top cover is welded and fixed to the electrode tab of the battery cell.

[0020] Secondly, embodiments of the present invention provide a battery, comprising:

[0021] The housing has a receiving cavity and an opening;

[0022] The battery cell is disposed within the receiving cavity; and,

[0023] As described in the foregoing embodiments, the top cover assembly is connected to the housing to close the opening, and the connector is electrically connected to the tab of the battery cell.

[0024] Thirdly, embodiments of this utility model provide a battery pack, comprising:

[0025] First battery cell; and,

[0026] The second battery cell is a battery as described in the previous embodiment. The welding part at the second end is welded and fixed to the first battery cell. The fusion structure is located between the welding part and the first end.

[0027] In one embodiment, the first battery cell is a battery as described in the previous embodiments, and the welding portion of the adjacent first battery cell is welded to the welding portion of the second battery cell.

[0028] Fourthly, embodiments of the present invention provide an electrical device, including a battery as described in the foregoing embodiments or a battery pack as described in the foregoing embodiments.

[0029] The beneficial effects of the embodiments of this utility model are as follows:

[0030] In embodiments of this invention, by incorporating a fusible structure on the connector, the fusible structure will melt first due to localized resistance heating or material softening when the battery experiences thermal runaway, actively cutting off the battery circuit and thus blocking continuous discharge, energy input and output, and heat generation. Furthermore, after the fusible structure has functioned, the battery can be recycled by re-welding another section of metal or alloy with a fusible structure, achieving battery reuse and significantly saving costs and improving battery utilization. Attached Figure Description

[0031] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0032] Figure 1 This is a schematic diagram of the top cover assembly provided in an embodiment of the present invention;

[0033] Figure 2 yes Figure 1 The diagram shows the structure of the top cover in the top cover assembly.

[0034] Figure 3 This is a schematic diagram of the connection between the two connectors provided in an embodiment of this utility model;

[0035] Figure 4 This is a cross-sectional view of the battery pack provided in an embodiment of this utility model;

[0036] Figure 5 It is at Figure 4 A magnified view of a section at point A in the middle;

[0037] Figure 6 It is at Figure 4 A magnified view of a section at point B in the middle;

[0038] Figure 7 This is a schematic diagram of the battery pack provided in an embodiment of the present invention.

[0039] The labels in the diagram are as follows:

[0040] 1. Top cover assembly;

[0041] 11. Top cover; 111. Inner surface; 112. Outer surface;

[0042] 12. Connector; 121. First end; 122. Second end; 123. Fusible structure; 1231. Fusible groove; 124. Welded part; 125. Pole post section; 126. Connecting section; 127. Bearing part;

[0043] 13. Fixed block;

[0044] 14. Insulating components;

[0045] 2. Battery;

[0046] 21. Shell;

[0047] 22. Battery cells;

[0048] 3. Battery pack;

[0049] 31. First battery cell;

[0050] 32. Second battery cell. Detailed Implementation

[0051] The embodiments of this application are described in detail below. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application.

[0052] To enable those skilled in the art to better understand the solutions of this application, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0053] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0054] Reference Figures 1 to 3The first aspect of this utility model provides a top cover assembly 1, including a top cover 11 and a connector 12. The top cover 11 includes an inner surface 111 and an outer surface 112. The inner surface 111 faces the battery cell 22, and the outer surface 112 is arranged opposite to the inner surface 111. The connector 12 is an integrally formed structure, and the connector 12 includes a first end 121 and a second end 122 arranged opposite to each other. The connector 12 passes through the top cover 11. The first end 121 is located on the side of the inner surface 111 of the top cover 11 for electrical connection with the battery cell 22. The second end 122 is located on the side of the outer surface 112 of the top cover 11, and a fusible structure 123 is provided on the second end 122.

[0055] The top cover 11 serves as the main body of the sealing structure in the battery 2, with its inner surface 111 facing the cell 22 to protect and seal the cell 22. The size and shape of the top cover 11 are usually determined according to the model of the battery 2, and this utility model does not impose any limitations on them.

[0056] The connector 12 is used to connect the battery cell 22 to external devices, which can be relay equipment such as busbars or electrical devices; this invention does not limit this. Since one end of the connector 12 connects to the tab of the battery cell 22, and the other end passes through the top cover 11 to connect to the external device, the connector 12 typically has a certain bending structure. Specifically, the thickness of the connector 12 can be controlled to be small, for example, less than 5mm, giving the connector 12 good flexibility. It can be bent according to actual needs, increasing the applicability of the connector 12 and making installation more flexible. Alternatively, the connector 12 can be manufactured with a bending structure so that bending is not required during installation, reducing the probability of damage to the connector 12. In this case, the flexibility requirement for the connector 12 is lower, allowing the use of a connector 12 with higher mechanical strength and extending its service life.

[0057] The fusible link structure 123 is a protective structure installed on the connector 12. When the battery 2 experiences thermal runaway, excessive current will cause the fusible link structure 123 to melt, thereby disconnecting the battery 2 and reducing the probability of the battery 2 burning or exploding. For example, the fusible link structure 123 may be a locally narrowed area at the second end 122 of the connector 12, thereby reducing the cross-sectional area of ​​the connector 12 to achieve melting; the fusible link structure 123 may also be a low-melting-point segment embedded at the second end 122 of the connector 12, such as a tin alloy segment or an indium alloy segment. By utilizing the lower melting point of the low-melting-point segment, the low-melting-point segment will melt quickly when the current is too large, thereby protecting the battery 2 and other circuit structures.

[0058] This embodiment of the invention features a fusible link structure 123 on the connector 12. When thermal runaway occurs in the battery 2, the fusible link structure 123 will melt first due to localized resistance heating or material softening, actively cutting off the battery 2 circuit. This blocks continuous discharge, energy input and output, and heat generation. Furthermore, after the fusible link structure 123 has functioned, the battery 2 can be recycled. By re-welding another section of metal or alloy with the fusible link structure 123, the battery 2 can be reused, significantly saving costs and improving its utilization rate.

[0059] In one embodiment, reference is made to Figure 3 The second end 122 is also provided with a welding part 124, which is used to weld with external devices to form an electrical connection; wherein, the fusion structure 123 is located in the part of the second end 122 between the welding part 124 and the outer surface 112.

[0060] By providing the welding part 124, the battery 2 can be connected to external devices through the welding part 124. The fusible structure 123 is provided outside the welding part 124 to prevent the part with the fusible structure 123 from being welded to the external device during welding, which would prevent the protective effect of the fusible structure 123 from being exerted.

[0061] In one embodiment, reference is made to Figure 4 and Figure 5 The connector 12 includes a pole section 125 and a connecting section 126. The pole section 125 passes through the top cover 11 so that the end of the pole section 125 near the cell 22 forms a first end 121. The connecting section 126 and the pole section 125 are bent and connected to form a second end 122. The fusible structure 123 is located on the side of the connecting section 126 near the pole section 125.

[0062] The connecting segment 126 is bent and connected to the terminal segment 125, allowing the connecting segment 126 to be connected to external devices by adjusting the connection angle with the terminal segment 125, thus improving the applicability of the connector 12 and the battery 2. For example, the connecting segment 126 can be connected perpendicularly to the terminal segment 125, allowing the connecting segment 126 to be connected to other devices along the thickness direction of the cell 22, improving the convenience of connecting the battery 2 to external devices. The fusible link 123 is located on the side of the connecting segment 126 closest to the terminal segment 125. This reduces the probability of the fusible link 123 breaking when the connecting segment 126 is connected to an external device, and also prevents the fusible link 123 from being too close to the battery 2, causing heat to dissipate into the battery 2 and affecting its normal operation.

[0063] In one embodiment, reference is made to Figure 5 and Figure 6The fusible link structure 123 includes a fusible link groove 1231. By providing the fusible link groove 1231 at the second end 122 of the connector 12, when the battery 2 experiences thermal runaway, the surge in current concentrates heat at the fusible link groove 1231, causing a rapid increase in local heat. This causes the weak point with the fusible link groove 1231 to melt, thereby quickly cutting off the circuit. Simultaneously, the integrally formed fusible link groove 1231 eliminates the need for additional parts, maintaining the structural integrity of the connector 12, achieving efficient space utilization, and reducing manufacturing costs.

[0064] In one embodiment, the fuse groove 1231 extends along the width direction of the second end 122, and the width of the fuse groove 1231 is equal to the width of the second end 122; and / or, the cross-sectional area of ​​the portion of the second end 122 located at the bottom wall of the fuse groove 1231 is greater than or equal to 4 square millimeters and less than or equal to 8 square millimeters.

[0065] The width of the fuse groove 1231 is equal to that of the second end 122, thereby covering the current path and ensuring that the entire conductive cross section will melt during thermal runaway. This reduces the probability of partial non-melting, which could lead to the circuit still being conductive during thermal runaway, and improves the safety of battery 2.

[0066] By controlling the cross-sectional area of ​​the portion of the second end 122 located on the bottom wall of the fuse groove 1231 within the range of 4 square millimeters to 8 square millimeters, it is ensured that the connector 12 has sufficient current carrying capacity when working normally, and that the connector 12 can quickly disconnect the circuit when there is an abnormal temperature rise, thereby improving the safety of the battery 2.

[0067] It should be noted that in this application, "and / or" describes the relationship between related objects, indicating that there can be three relationships. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, the character " / ", unless otherwise specified, generally indicates that the related objects before and after it are in an "or" relationship.

[0068] In one embodiment, reference is made to Figure 5 The top cover assembly 1 also includes a fixing block 13, which is disposed on the outer surface 112, and the second end 122 is riveted or welded to the fixing block 13.

[0069] The fixing block 13 is disposed on the outer surface 112 of the top cover 11 and is used to fix the part of the connector 12 exposed on the outer surface 112 of the top cover 11. The fixing block 13 can be connected to the connector 12 by riveting or welding. Riveting generates less heat and can reduce the impact on other structures in the battery 2. Welding can improve the connection strength and sealing of the connection between the fixing block 13 and the connector 12.

[0070] In one embodiment, reference is made to Figure 5The top cover assembly 1 also includes a seal, and the connector 12 includes a support portion 127, which protrudes from the outer periphery of the first end 121, and at least part of the seal is sandwiched between the inner surface 111 and the support portion 127.

[0071] The support portion 127, as a protrusion extending from the outer periphery of the first end 121 of the connector 12, provides stable support for the seal, ensuring that the seal is subjected to sufficient pressure during assembly, thereby forming a reliable sealing interface. Specifically, the support portion 127 may be a protrusion located on the outer periphery of the first end 121, contacting a portion of the bottom surface of the seal, thereby providing upward pressure to the seal.

[0072] Understandably, the support portion 127 also plays a certain positioning role, making it easier to install the seal between the inner surface 111 of the top cover 11 and the support portion 127, and by adjusting the thickness of the support portion 127, it can be compatible with seals of different thicknesses.

[0073] In one embodiment, the support portion 127 is disposed around the first end 121. Specifically, the support portion 127 may include multiple protrusions arranged around the outer peripheral surface of the first end 121, so that the seal is subjected to more uniform pressure, reducing the probability of seal failure due to damage to the seal or uneven pressure. The support portion 127 may also be a complete annular structure, further increasing the contact area between the support portion 127 and the seal, reducing the pressure between the support portion 127 and the seal, and preventing damage to the seal.

[0074] In one embodiment, the support portion 127 is welded and fixed to the tab of the battery cell 22 on the side opposite to the top cover 11. Accordingly, the support portion 127 also plays a certain connecting role, increasing the connection area between the connector 12 and the tab, reducing the resistance at the connection point, and thus improving the current carrying capacity of the top cover assembly 1.

[0075] In one embodiment, reference is made to Figure 5 The top cover assembly 1 also includes an insulating member 14, at least a portion of which is disposed on the side of the inner surface 111 of the top cover 11 to insulate the top cover 11 from the battery cell 22; wherein, at least a portion of the insulating member 14 is sandwiched between the support portion 127 and the top cover 11. Accordingly, the insulating member 14 can reduce the possibility of short circuit between the connector 12 and the top cover 11, ensuring the safe use of the battery 2.

[0076] According to a second aspect of the present invention, referring to Figure 4A battery 2 is provided, including a housing 21, a battery cell 22, and a top cover assembly 1 as described in the previous embodiment. The housing 21 has a receiving cavity and an opening; the battery cell 22 is disposed in the receiving cavity; the top cover 11 and the housing 21 are connected to close the opening, and a connector 12 is electrically connected to the tabs of the battery cell 22. The battery pack 3 includes the aforementioned top cover assembly 1, therefore the battery 2 has all the beneficial effects of the aforementioned top cover assembly 1, and the embodiments of this utility model will not be described in detail here.

[0077] The housing 21 can be a rigid housing, such as a rigid plastic housing, an aluminum housing, or a steel housing; the housing 21 can also be a flexible housing, such as a pouch-type flexible housing. The material of the flexible housing can be plastic, such as at least one of polypropylene (PP), polybutylene terephthalate (PBT), and polybutylene succinate (PBS).

[0078] The battery 2 of this application may be in the form of a single battery cell, a battery module, or a battery pack 3. In some embodiments, the single battery cell can be assembled into a battery module, and the number of single battery cells contained in the battery module can be one or more, the specific number of which can be selected by those skilled in the art based on the application and capacity of the battery module. In some embodiments, the battery module can also be assembled into a battery pack 3, and the number of battery modules contained in the battery pack 3 can be one or more, the specific number of which can be selected by those skilled in the art based on the application and capacity of the battery pack 3.

[0079] According to a third aspect of this utility model, referring to Figure 3 and Figure 7 A battery pack 3 is provided, including a first battery cell 31 and a second battery cell 32. The second battery cell 32 is the battery 2 in the aforementioned embodiment. The welding portion 124 of the second end 122 is welded and fixed to the first battery cell 31, and the fusion structure 123 is located between the welding portion 124 and the first end 121. Since the second battery cell 32 is the battery 2 in the aforementioned embodiment, the battery pack 3 has all the beneficial effects of the aforementioned battery 2, which will not be described in detail here. By directly connecting the first battery cell 31 through the welding portion 124 of the connector 12, the setting of structures such as busbars is reduced, saving the installation space of the battery pack 3, allowing more batteries 2 to be accommodated in the battery pack 3, thereby improving the energy density of the battery pack 3.

[0080] In one embodiment, reference is made to Figure 3 and Figure 7The first battery cell 31 is the battery 2 in the aforementioned embodiment. The welding portion 124 of adjacent first battery cells 31 is welded to the welding portion 124 of the second battery cell 32. Both the first battery cell 31 and the second battery cell 32 are provided with welding portions 124, so that the circuit can be made conductive by connecting the welding portions 124 in pairs. This completely eliminates the need for busbars and other structures, further increasing the installation space of the battery pack 3, allowing more batteries 2 to be accommodated in the battery pack 3, thereby increasing the energy density of the battery pack 3.

[0081] According to a fourth aspect of this utility model, an electrical device is provided, which includes the battery 2 or battery pack 3 in the foregoing embodiments. Therefore, this electrical device possesses all the beneficial effects of the aforementioned battery 2 or battery pack 3, and the embodiments of this utility model will not be repeated here. As one embodiment, the electrical device can be a pure electric vehicle, a hybrid electric vehicle, a plug-in hybrid electric vehicle, etc. To meet the high power and high energy density requirements of the battery 2, a battery pack 3 or a battery 2 module can be used. As another embodiment, the device can be a mobile phone, tablet computer, laptop computer, etc. This device typically requires a thin and light design, and a single battery 2 cell can be used as the power source.

[0082] In the description of this application, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more features. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0083] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0084] The embodiments, implementation methods, and related technical features of this application can be combined and substituted for each other without conflict.

[0085] The above are merely preferred embodiments of this application and are not intended to limit this application in any way. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of this application without departing from the scope of the technical solution of this application shall still fall within the scope of the technical solution of this application.

Claims

1. A cap assembly, characterized by, include: A top cover, the top cover including an inner surface and an outer surface, the inner surface being oriented toward the battery cell, and the outer surface being disposed opposite to the inner surface; The connector is an integrally formed structure. The connector includes a first end and a second end arranged opposite to each other. The connector passes through the top cover. The first end is located on the inner surface of the top cover for electrical connection with the battery cell. The second end is located on the outer surface of the top cover and is provided with a fusible structure.

2. The roof assembly of claim 1, wherein, The second end is also provided with a welding part, which is used to weld with external devices to form an electrical connection; The fusion structure is located at the portion of the second end between the welded portion and the outer surface.

3. The roof assembly of claim 2, wherein, The connector includes: A terminal section, the terminal section passing through the top cover, such that the end of the terminal section near the battery cell forms the first end; and, A connecting segment, which is bent and connected to the pole segment to form the second end, wherein the fusible structure is located on the side of the connecting segment closer to the pole segment.

4. The roof assembly of any one of claims 1 to 3, wherein, The fusion structure includes a fusion groove.

5. The roof assembly of claim 4, wherein, The fusible groove extends along the width direction of the second end, and the width of the fusible groove is equal to the width of the second end; and / or, The cross-sectional area of ​​the portion of the second end located on the bottom wall of the fuse groove is greater than or equal to 4 square millimeters and less than or equal to 8 square millimeters.

6. The roof assembly of any one of claims 1 to 3, wherein, The top cover assembly also includes a fixing block, which is disposed on the outer surface, and the second end is riveted or welded to the fixing block.

7. The roof assembly of claim 6, wherein, The top cover assembly further includes a seal, and the connector includes a support portion that protrudes from the outer periphery of the first end, with at least a portion of the seal sandwiched between the inner surface and the support portion.

8. The roof assembly of claim 7, wherein, The supporting part is arranged around the first end.

9. The roof assembly of claim 8, wherein, The side of the supporting part away from the top cover is welded and fixed to the electrode tab of the battery cell.

10. A battery, characterized by include: A housing, the housing having a receiving cavity and an opening; A battery cell, wherein the battery cell is disposed within the receiving cavity; and, The top cover assembly as claimed in any one of claims 1 to 9, wherein the top cover and the housing are connected to close the opening, and the connector is electrically connected to the tab of the battery cell.

11. A battery pack, characterized by include: First battery cell; and, The second battery cell is the battery as described in claim 10, wherein the welding portion at the second end is welded and fixed to the first battery cell, and the fusion structure is located between the welding portion and the first end.

12. The battery pack of claim 11, wherein, The first battery cell is the battery as described in claim 10, and the welding portion of the adjacent first battery cell is welded to the welding portion of the second battery cell.

13. An electrical device, characterized by Includes the battery as described in claim 10 or the battery pack as described in claim 11 or 12.

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