Battery monomer, battery device and electric device

Abstract

The utility model provides a battery monomer, a battery device and a power utilization device. The battery monomer comprises a shell, an electrode assembly, a pressure relief mechanism, a current collecting component and a connecting piece, the shell is provided with a wall part, the electrode assembly is accommodated in the shell, and the pressure relief mechanism is arranged on the wall part. The current collecting member is provided between the electrode assembly and the wall portion in the first direction. The flow collecting component is provided with a pressure relief channel, and the pressure relief channel penetrates through the flow collecting component in the first direction. The connecting piece is connected to the flow collecting component, at least part of the connecting piece is contained in the pressure relief channel, and the connecting piece is configured to be at least partially damaged before the pressure relief mechanism is actuated. When the single battery is normally used, the connecting piece can reinforce the current collecting component, so that the current collecting component has enough strength to support the electrode assembly, and the use performance of the single battery is favorably maintained. And when the battery monomers are in thermal runaway, at least part of the connecting piece is damaged, and emissions on one side of the current collecting component can quickly flow to the pressure relief mechanism through the pressure relief channel, so that the pressure relief mechanism can be quickly actuated.

Description

Technical Field

[0001] This application relates to the field of batteries, and more specifically, to a battery cell, a battery device, and an electrical device. Background Technology

[0002] Batteries are widely used in the new energy field, such as in electric vehicles and new energy vehicles, which have become a new trend in the automotive industry. The development of battery technology must consider multiple design factors simultaneously, such as cycle life, discharge capacity, and charge / discharge rate. However, after a period of use, battery performance will significantly decrease. Utility Model Content

[0003] The purpose of this application is to provide a battery cell, a battery device, and an electrical device, which aims to improve the problem in the related art that the performance of the battery will be significantly reduced after a period of use.

[0004] In a first aspect, embodiments of this application provide a battery cell, the battery cell including a housing, an electrode assembly, a pressure relief mechanism, a current collector, and a connector. The housing has a wall portion; the electrode assembly is housed within the housing; the pressure relief mechanism is disposed on the wall portion and configured to be actuated when the internal pressure or temperature of the battery cell reaches a threshold value to release the internal pressure of the battery cell; the current collector is disposed between the electrode assembly and the wall portion along a first direction and electrically connects the electrode assembly and the wall portion, the current collector having a pressure relief channel extending through the current collector along the first direction; the connector is connected to the current collector and is at least partially housed within the pressure relief channel, the connector being configured to be at least partially destroyed before the pressure relief mechanism is actuated.

[0005] In the above technical solution, by setting a connector on the current collector and having the connector at least partially housed within the pressure relief channel, the connector can strengthen the current collector when the battery cell is in normal use, giving it sufficient strength to support the electrode assembly and thus helping to maintain the battery cell's performance. When the battery cell experiences thermal runaway, the internal pressure and temperature of the battery cell rise, and the connector can be at least partially destroyed under the influence of the internal pressure and / or temperature of the battery cell. This allows the discharge from the side of the current collector facing the electrode assembly to flow quickly through the pressure relief channel to the pressure relief mechanism, enabling the pressure relief mechanism to be actuated rapidly. This shortens the time from the battery cell's thermal runaway to the start of pressure relief through the pressure relief mechanism, reducing the risk of battery cell explosion and fire, and effectively improving the reliability of the battery cell.

[0006] As an optional technical solution in this application embodiment, the pressure relief channel includes multiple sub-channels, the multiple sub-channels are arranged circumferentially along the current collection component, the multiple sub-channels intersect each other, the current collection component includes multiple pressure relief zones, a pressure relief zone is provided between two adjacent sub-channels along the circumferential direction of the current collection component, and the connector is at least partially located in the sub-channel and connects the multiple pressure relief zones.

[0007] In the above technical solution, by setting multiple interconnected sub-channels and establishing a pressure relief zone between adjacent sub-channels, the strength around the pressure relief zone is relatively low. When a battery cell experiences thermal runaway, the connector can be at least partially destroyed under the internal pressure and / or temperature of the battery cell. The pressure relief zone can then flip open towards the pressure relief mechanism under the internal pressure of the battery cell, forming a larger opening on the current collector. This allows the discharge from the side of the current collector facing the electrode assembly to flow quickly to the pressure relief mechanism, enabling the mechanism to actuate more quickly. This further shortens the time from battery cell thermal runaway to the start of pressure relief by the mechanism, further reducing the risk of battery cell explosion and fire, and effectively improving the reliability of the battery cell. Furthermore, because the current collector has multiple interconnected sub-channels, its strength is further weakened. Therefore, it is necessary to install connectors to strengthen the current collector, ensuring it has sufficient strength to support the electrode assembly, thus helping to maintain the performance of the battery cell.

[0008] As an optional technical solution in this application embodiment, along the first direction, the current collecting member has a first surface facing the electrode assembly, the first surface is provided with a groove, a portion of the sub-channel and a portion of the pressure relief area are located on the bottom wall of the groove, the portions of the multiple sub-channels located on the bottom wall of the groove intersect, a portion of the connector is accommodated in the sub-channel, and another portion of the connector is accommodated in the groove.

[0009] In the above technical solution, by setting a groove on the first surface, a part of the connector is accommodated in the groove, which helps to reduce the height of the connector protruding from the first surface, thereby reducing the risk of interference between the connector and the electrode assembly.

[0010] As an optional technical solution in this application embodiment, along the first direction, the current collection member has a second surface disposed opposite to the first surface; along the direction from the second surface to the first surface, the connector does not extend beyond the first surface.

[0011] In the above technical solution, by ensuring that the connector does not extend beyond the first surface in the direction from the second surface to the first surface, that is, the connector does not protrude beyond the first surface in the direction from the second surface to the first surface, on the one hand, it is beneficial to reduce the risk of interference between the connector and the electrode assembly, and on the other hand, it is beneficial to make the first surface and the electrode assembly's tab fit together, thereby facilitating the welding of the current collector and the electrode assembly.

[0012] As an optional technical solution in this application embodiment, along the first direction, the connector has a third surface that is closest to the first surface, and the distance between the first surface and the third surface is H1, which satisfies: H1≥0.1mm.

[0013] In the above technical solution, when H1 ≥ 0.1 mm, the distance between the first and third surfaces along the first direction is relatively large, which helps reduce the risk of interference between the connector and other components. The large distance between the first and third surfaces along the first direction also facilitates close contact between the first surface and the electrode assembly's tabs, thereby simplifying the welding of the current collector and electrode assembly. Furthermore, due to the large distance between the first and third surfaces along the first direction, the heat generated during welding of the current collector and electrode assembly has a smaller impact on the connector.

[0014] As an optional technical solution in this application embodiment, the pressure relief area includes a first part located on the bottom wall of the groove, at least one of the first parts is provided with a receiving part, and a part of the connector is received in the receiving part.

[0015] In the above technical solution, by providing a receiving portion on the first part and housing a portion of the connector within the receiving portion, on the one hand, it is beneficial to increase the contact area between the connector and the first part, thereby improving the connection strength between the connector and the first part and enhancing the reinforcing effect of the connector on the current collector. This ensures that the current collector has sufficient strength to support the electrode assembly, thus helping to maintain the performance of the battery cell. On the other hand, the connector can form a limiting fit with the receiving portion, thereby reducing the risk of the connector moving relative to the current collector.

[0016] As an optional technical solution in this application embodiment, the receiving portion is a through hole that penetrates the first part along the first direction.

[0017] In the above technical solution, when the receiving part is a through hole penetrating the first part along the first direction, a portion of the connector can be inserted into the through hole. The contact area between the connector and the first part is large, and the connector provides better reinforcement to the current collecting component. Furthermore, when the connector mates with the through hole, it provides a good limiting effect on the connector, thereby reducing the risk of the connector moving relative to the current collecting component.

[0018] As an optional technical solution in this application embodiment, the sub-channel includes a first channel segment disposed on the bottom wall of the groove. The first channel segment includes two opposing walls, which are respectively located in two adjacent first portions. At least one wall of at least one first channel segment is provided with the receiving portion, which penetrates through the first portion along the first direction.

[0019] In the above technical solution, when at least one wall surface of at least one first channel segment is provided with a receiving portion, the connector has a protrusion corresponding to the receiving portion. The protrusion and the receiving portion cooperate together, thereby improving the connection strength between the connector and the first part, enhancing the reinforcing effect of the connector on the current collecting component, and reducing the risk of the connector moving relative to the current collecting component. By making the receiving portion penetrate through the first part along the first direction, it is beneficial to increase the contact area between the connector and the first part, thereby improving the connection strength between the connector and the first part and enhancing the reinforcing effect of the connector on the current collecting component.

[0020] As an optional technical solution in this application embodiment, at least two of the walls of the first channel segment are provided with the receiving portion.

[0021] In the above technical solution, by providing receiving portions on two walls of at least one first channel segment, the connection strength between the connector and the first part is further enhanced, and the strengthening effect of the connector on the flow collecting component is further improved. Simultaneously, it effectively limits the connector, reducing the risk of movement of the connector relative to the flow collecting component.

[0022] As an optional technical solution in this application embodiment, the sub-channel includes a first channel segment disposed on the bottom wall of the groove, and at least one first channel segment includes a plurality of sub-segments connected in sequence, with the extension directions of two adjacent sub-segments intersecting.

[0023] In the above technical solution, by making at least one first channel segment include multiple sub-segments connected in sequence, and making the extension directions of two adjacent sub-segments intersect, on the one hand, it is beneficial to increase the contact area between the connector and the first part, thereby improving the connection strength between the connector and the first part and enhancing the strengthening effect of the connector on the current collecting component. On the other hand, the connector can form a limiting fit with multiple sub-segments, thereby reducing the risk of the connector moving relative to the current collecting component.

[0024] As an optional technical solution in this application embodiment, the sub-channel includes a first channel segment disposed on the bottom wall of the groove, and the connector blocks the first channel segment.

[0025] In the above technical solution, while the connector blocks the first channel segment, it also connects the two opposite walls of the first channel segment, thereby connecting multiple pressure relief zones. This gives the current collector sufficient strength to support the electrode assembly, thus helping to maintain the performance of the battery cell. Furthermore, because the connector blocks the first channel segment, in the event of thermal runaway of the battery cell, the pressure on the side of the current collector facing the electrode assembly will rise rapidly. This allows the connector to be quickly destroyed under pressure, and the pressure relief zone can flip open towards the pressure relief mechanism under pressure, forming a larger opening on the current collector. This allows the discharge from the side of the current collector facing the electrode assembly to flow quickly to the pressure relief mechanism through this opening, enabling the pressure relief mechanism to actuate more quickly and improving the reliability of the battery cell.

[0026] As an optional technical solution in this application embodiment, the sub-channel includes a first channel segment disposed on the bottom wall of the groove, the connector includes a first connecting part, a second connecting part and a third connecting part, along the first direction, the first connecting part and the third connecting part are respectively located on both sides of the bottom wall of the groove, the second connecting part connects the first connecting part and the third connecting part, and at least part of the second connecting part is accommodated in the first channel segment.

[0027] In the above technical solution, the first connecting part and the third connecting part are located on both sides of the bottom wall of the groove along the first direction, and the second connecting part is at least partially accommodated in the first channel section and connects the first connecting part and the third connecting part, so that the connecting part is tightly connected with multiple pressure relief areas, which is beneficial to improving the strengthening effect of the current collecting component, so that the current collecting component has sufficient strength to support the electrode assembly, thereby helping to maintain the performance of the battery cell.

[0028] As an optional technical solution in this application embodiment, along the first direction, the minimum distance between the surface of the first connecting part away from the third connecting part and the surface of the third connecting part away from the first connecting part is H3, which satisfies: 0.4mm≤H2≤1.2mm.

[0029] In the above technical solution, when H2 ≥ 0.4 mm, the minimum distance between the surface of the first connecting part and the surface of the third connecting part facing away from the first connecting part is relatively large along the first direction, that is, the minimum thickness of the connector is relatively large, resulting in greater strength of the connector. This provides better reinforcement to the current collector, ensuring sufficient strength to support the electrode assembly, thus helping to maintain the performance of the battery cell. When H2 ≤ 1.2 mm, the minimum distance between the surface of the first connecting part and the surface of the third connecting part facing away from the first connecting part along the first direction is not too large. On the one hand, this prevents the strength of the connector from becoming too high, allowing the connector to be quickly destroyed when the battery cell experiences thermal runaway. This facilitates the rapid flow of discharge from the side of the current collector facing the electrode assembly through the pressure relief channel to the pressure relief mechanism, enabling the pressure relief mechanism to actuate quickly. On the other hand, the connector is less likely to interfere with other components, which helps improve the reliability of the battery cell. Furthermore, the connector occupies less internal space in the battery cell, which helps to increase the energy density of the battery cell.

[0030] As an optional technical solution in this application embodiment, the orthographic projection of the connector along the first direction is circular, and the diameter of the circle is D, which satisfies: 3mm≤D≤10mm.

[0031] In the above technical solution, when D≥3mm, the diameter of the circle projected by the connector along the first direction is relatively large, which is beneficial to increasing the contact area between the connector and the current collector, thus providing a better strengthening effect on the current collector and giving it sufficient strength to support the electrode assembly, thereby helping to maintain the performance of the battery cell. When D≤10mm, the diameter of the circle projected by the connector along the first direction is not too large. On the one hand, when the battery cell experiences thermal runaway, the connector can be quickly destroyed, allowing the discharge from the side of the current collector facing the electrode assembly to flow quickly to the pressure relief mechanism through the pressure relief channel, enabling the pressure relief mechanism to be actuated quickly. On the other hand, the connector is less likely to interfere with other components, which is beneficial to improving the reliability of the battery cell. Furthermore, the connector occupies less internal space in the battery cell, which is beneficial to increasing the energy density of the battery cell.

[0032] As an optional technical solution in this application embodiment, the depth of the groove is H3, which satisfies: 0.2mm≤H3≤1.3mm, and optionally, 0.2mm≤H3≤0.7mm.

[0033] In the above technical solution, when H3 ≥ 0.2 mm, the groove depth is relatively large, which can accommodate a larger connector, giving the connector sufficient strength to effectively reinforce the current collector. This, in turn, ensures the current collector has sufficient strength to support the electrode assembly, thus helping to maintain the performance of the battery cell. When H3 ≤ 1.3 mm, the groove depth is not too large, which helps to reduce the space occupied by the current collector in the first direction and improves the energy density of the battery cell.

[0034] When H3 ≥ 0.2 mm, the groove depth is relatively large, which can accommodate larger connectors, giving the connectors sufficient strength to effectively reinforce the current collector. This, in turn, provides sufficient strength for the current collector to support the electrode assembly, thus helping to maintain the performance of the battery cell. When H3 ≤ 0.7 mm, the groove depth is not too large, which helps to reduce the space occupied by the current collector in the first direction and improves the energy density of the battery cell.

[0035] As an optional technical solution in this application embodiment, along the first direction, the flow collecting member has a second surface disposed opposite to the first surface; the area of ​​the flow collecting member corresponding to the groove is formed with a protrusion protruding from the second surface.

[0036] In the above technical solution, by deforming a portion of the current collecting component along the direction from the first surface to the second surface to form a groove and a protrusion, on the one hand, the molding difficulty of the groove is reduced. On the other hand, it is beneficial to make the bottom wall of the groove thicker, so that the portion of the pressure relief zone located on the bottom wall of the groove is thicker, and the portion of the pressure relief zone located on the bottom wall of the groove and the portion of the pressure relief zone located outside the groove are less likely to break, thereby improving the connection strength between the connector and the pressure relief zone.

[0037] As an optional technical solution in this application embodiment, the melting point of the connector is lower than the melting point of the current collector.

[0038] In the above technical solution, by making the melting point of the connector lower than that of the current collector, when the battery cell experiences thermal runaway, the internal pressure and temperature of the battery cell increase. The connector can be at least partially destroyed under the internal pressure and temperature of the battery cell, thereby allowing the discharge from the side of the current collector facing the electrode assembly to flow quickly to the pressure relief mechanism through the pressure relief channel. This enables the pressure relief mechanism to be actuated quickly, shortening the time from the battery cell's thermal runaway to the battery cell starting to depressurize through the pressure relief mechanism. This reduces the risk of battery cell explosion and fire, and effectively improves the reliability of the battery cell.

[0039] As an optional technical solution in this application embodiment, the material of the connector includes at least one of plastic and rubber.

[0040] In the above technical solution, the plastic and rubber materials have low strength and melting point. When the battery cell experiences thermal runaway, the connector is quickly destroyed under the internal pressure and temperature of the battery cell. This allows the discharge from the side of the current collector facing the electrode assembly to flow quickly to the pressure relief mechanism through the pressure relief channel, enabling the pressure relief mechanism to be actuated quickly and improving the reliability of the battery cell.

[0041] As an optional technical solution in this application embodiment, the connector is injection molded onto the flow collector component.

[0042] In the above technical solution, by injection molding the connector onto the current collector, the connection strength between the connector and the current collector is moderate. This ensures that the current collector has sufficient strength to support the electrode assembly during normal use of the battery cell, thus maintaining the battery cell's performance. Furthermore, in the event of thermal runaway in the battery cell, the connector can be quickly destroyed, allowing the discharge from the side of the current collector facing the electrode assembly to flow rapidly through the pressure relief channel to the pressure relief mechanism, enabling the mechanism to actuate quickly.

[0043] As an optional technical solution in this application embodiment, the connector blocks part of the pressure relief channel.

[0044] In the above technical solution, by blocking part of the pressure relief channel with the connector, it is beneficial to simplify manufacturing, reduce manufacturing costs, and allow the discharge from the side of the current collector facing the electrode assembly to flow to the pressure relief mechanism through the pressure relief channel when the battery cell is in normal use.

[0045] As an optional technical solution in this application embodiment, the connector blocks the entire pressure relief channel.

[0046] In the above technical solution, by blocking the entire pressure relief channel with the connector, the reinforcement effect of the current collector is improved, so that the current collector has sufficient strength to support the electrode assembly, thereby helping to maintain the performance of the battery cell.

[0047] As an optional technical solution in this application embodiment, there is a gap between the connector and the pressure relief mechanism along the first direction.

[0048] In the above technical solution, by making the connecting part have a gap with the pressure relief mechanism along the first direction, the connecting part and the pressure relief mechanism do not come into contact, and it is not easy to affect the burst pressure of the pressure relief mechanism.

[0049] As an optional technical solution in this application embodiment, the electrode assembly includes a tab; the current collector includes a first current collector and a second current collector connected together, the base metal of the first current collector and the second current collector are different, the base metal of the first current collector and the tab are the same, the first current collector is welded to the tab, the base metal of the second current collector and the wall is the same, the second current collector is welded to the wall, and the pressure relief channel is disposed in the first current collector.

[0050] In the above technical solution, by making the base metal of the first current collector and the electrode tab the same, it is possible to achieve welding between the first current collector and the electrode tab using the same base metal. This alleviates the differences in melting point and thermal expansion coefficient caused by welding with different base metals, thereby reducing the occurrence of welding cracks between the first current collector and the electrode tab and improving the welding quality. Similarly, by making the base metal of the second current collector and the wall portion the same, it is possible to achieve welding between the second current collector and the wall portion using the same base metal. This alleviates the differences in melting point and thermal expansion coefficient caused by welding with different base metals, thereby reducing the occurrence of welding cracks between the second current collector and the wall portion and improving the welding quality.

[0051] As an optional technical solution in this application embodiment, the second current collector is an annular structure and has a central hole; along the first direction, the orthogonal projection of the pressure relief channel is at least partially located within the central hole.

[0052] In the above technical solution, by making the orthogonal projection of the pressure relief channel along the first direction at least partially located in the central hole, it is beneficial to reduce the obstruction of the pressure relief channel by the second current collector, and facilitate the discharge of the current collector component on the side facing the electrode assembly to flow quickly to the pressure relief mechanism through the pressure relief channel.

[0053] As an optional technical solution in this application embodiment, in a projection plane perpendicular to the first direction, the orthographic projection of the second current collector is arranged around the outside of the orthographic projection of the pressure relief channel.

[0054] In the above technical solution, by making the orthographic projection of the second current collector in the projection plane perpendicular to the first direction surround the outside of the orthographic projection of the pressure relief channel in the projection plane perpendicular to the first direction, the second current collector is less likely to block the pressure relief channel, so that the discharge from the side of the current collector facing the electrode assembly can flow quickly to the pressure relief mechanism through the pressure relief channel.

[0055] Secondly, embodiments of this application also provide a battery device, which includes the aforementioned battery cell.

[0056] Thirdly, embodiments of this application also provide an electrical device, which includes the aforementioned battery cell, and the battery cell is used to provide electrical energy to the electrical device. Attached Figure Description

[0057] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0058] Figure 1 This application provides structural schematic diagrams of vehicles for some embodiments;

[0059] Figure 2 Exploded views of battery devices provided in some embodiments of this application;

[0060] Figure 3 Exploded views of a single battery cell provided in some embodiments of this application;

[0061] Figure 4 This is a schematic diagram of the connection between the current collection component and the connector provided in some embodiments of this application;

[0062] Figure 5 Exploded views of current collection components and connectors provided in some embodiments of this application;

[0063] Figure 6 This application provides a schematic diagram of the structure of a first current collector according to some embodiments;

[0064] Figure 7 A top view schematic diagram of a first current collector provided for some embodiments of this application;

[0065] Figure 8 Cross-sectional views of a battery cell provided in some embodiments of this application;

[0066] Figure 9 for Figure 8 A magnified view of position A in the middle;

[0067] Figure 10 Schematic diagram of the structure of the first current collector provided for other embodiments of this application;

[0068] Figure 11 A top view schematic diagram of a first current collector provided for other embodiments of this application;

[0069] Figure 12 A schematic diagram of the structure of the first current collector provided for some embodiments of this application;

[0070] Figure 13 A top view schematic diagram of a first current collector provided for some embodiments of this application.

[0071] Icons: 10-Box body; 11-First box body; 12-Second box body; 20-Battery cell; 21-Outer shell; 211-Housing shell; 212-End cap; 213-Wall; 22-Electrode assembly; 221-Main body; 222-Electrode tab; 23-Pressure relief mechanism; 231-Weak part; 232-Pressure relief groove; 24-Current collector; 241-First current collector; 2411-Pressure relief area; 24111-First part; 24121-First surface; 24122-Second surface; 2413-Groove ; 2414-Receiving part; 2415-Protrusion; 242-Second current collector; 2421-Center hole; 25-Connector; 251-First connecting part; 252-Second connecting part; 253-Third connecting part; 2511-Third surface; 26-Pressure relief channel; 261-First channel section; 2611-Wall surface; 2612-Sub-segment; 262-Second channel section; 263-Sub-channel; 27-Electrode terminal; 100-Battery device; 200-Controller; 300-Motor; 1000-Vehicle. Detailed Implementation

[0072] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0073] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used in the description of this application 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 description, claims, and accompanying drawings of this application are intended to cover non-exclusive inclusion. The terms "first," "second," etc., in the description, claims, or accompanying drawings of this application are used to distinguish different objects, not to describe a specific order or hierarchy.

[0074] In this application, the reference to "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 in the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment that is mutually exclusive with other embodiments.

[0075] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "attachment" 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; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0076] 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, or B existing alone. Additionally, in this application, the character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0077] In the embodiments of this application, the same reference numerals denote the same components, and for the sake of brevity, detailed descriptions of the same components are omitted in different embodiments. It should be understood that the thickness, length, width, and other dimensions of various components in the embodiments of this application shown in the accompanying drawings, as well as the overall thickness, length, width, and other dimensions of the integrated device, are merely illustrative and should not constitute any limitation on this application.

[0078] In this application, "multiple" means two or more (including two).

[0079] In this embodiment of the application, the battery cell can be a secondary battery, which refers to a battery cell that can be recharged to activate the active materials and continue to be used after the battery cell has been discharged.

[0080] Battery cells include, but are not limited to, lithium-ion batteries, sodium-ion batteries, sodium-lithium-ion batteries, lithium metal batteries, sodium metal batteries, lithium-sulfur batteries, magnesium-ion batteries, nickel-metal hydride batteries, nickel-cadmium batteries, lead-acid batteries, etc.

[0081] A single battery cell typically includes an electrode assembly. The electrode assembly includes a positive electrode, a negative electrode, and a separator. During the charging and discharging process of a single battery cell, active ions (such as lithium ions) repeatedly insert and extract between the positive and negative electrodes. The separator, positioned between the positive and negative electrodes, reduces the risk of short circuits while allowing active ions to pass through.

[0082] In some embodiments, the positive electrode may be a positive electrode sheet, which may include a positive electrode current collector and a positive electrode active material disposed on at least one surface of the positive electrode current collector.

[0083] As an example, the positive current collector has two surfaces opposite each other in its own thickness direction, and the positive active material is disposed on either or both of the two opposite surfaces of the positive current collector.

[0084] As an example, the positive electrode current collector can be a metal foil or a composite current collector. For example, as a metal foil, it can be aluminum with a silver-plated surface, stainless steel with a silver-plated surface, stainless steel, copper, aluminum, nickel, carbon electrode, carbon, nickel, or titanium, etc. Composite current collectors can include a polymer material base layer and a metal layer. Composite current collectors can be formed by forming a metal material (aluminum, aluminum alloy, nickel, nickel alloy, titanium, titanium alloy, silver and silver alloy, etc.) on a polymer material substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0085] As an example, the positive electrode active material may include at least one of the following materials: lithium phosphate, lithium transition metal oxide, and their respective modified compounds. However, this application is not limited to these materials, and other conventional materials that can be used as positive electrode active materials in battery cells may also be used. These positive electrode active materials may be used alone or in combination of two or more. Examples of lithium phosphate may include, but are not limited to, at least one of lithium iron phosphate (such as LiFePO4 (also referred to as LFP)), lithium iron phosphate and carbon composites, lithium manganese phosphate (such as LiMnPO4), lithium manganese phosphate and carbon composites, lithium iron manganese phosphate, and lithium iron manganese phosphate and carbon composites. Examples of lithium transition metal oxide may include, but are not limited to, lithium cobalt oxide (such as LiCoO2), lithium nickel oxide (such as LiNiO2), lithium manganese oxide (such as LiMnO2, LiMn2O4), lithium nickel cobalt oxide, lithium manganese cobalt oxide, lithium nickel manganese oxide, and lithium nickel cobalt manganese oxide (such as LiNi). 1 / 3 Co 1 / 3Mn 1 / 3 O2 (also known as NCM) 333 LiNi 0.5 Co 0.2 Mn 0.3 O2 (also known as NCM) 523 LiNi 0.5 Co 0.25 Mn 0.25 O2 (also known as NCM) 211 LiNi 0.6 Co 0.2 Mn 0.2 O2 (also known as NCM) 622 LiNi 0.8 Co 0.1 Mn 0.1 O2 (also known as NCM)811 ), lithium nickel cobalt aluminum oxide (such as LiNi) 0.85 Co 0.15 Al 0.05 At least one of O2 and its modified compounds.

[0086] In some embodiments, the positive electrode can be a foamed metal. The foamed metal can be foamed nickel, foamed copper, foamed aluminum, foamed alloys, etc. When foamed metal is used as the positive electrode, the surface of the foamed metal may or may not contain a positive electrode active material. As an example, lithium source material, potassium metal, or sodium metal can also be filled and / or deposited within the foamed metal, where the lithium source material is lithium metal and / or a lithium-rich material.

[0087] In some embodiments, the negative electrode may be a negative electrode sheet, and the negative electrode sheet may include a negative electrode current collector.

[0088] As an example, the negative electrode current collector can be a metal foil, a foamed metal, or a composite current collector. For example, as a metal foil, it can be aluminum with a silver-plated surface, stainless steel with a silver-plated surface, stainless steel, copper, aluminum, nickel, carbon electrodes, carbon, nickel, or titanium, etc. Foamed metal can be nickel foam, copper foam, aluminum foam, foam alloy, etc. Composite current collectors can include a polymer material base layer and a metal layer. Composite current collectors can be formed by forming a metal material (copper, copper alloy, nickel, nickel alloy, titanium, titanium alloy, silver and silver alloy, etc.) on a polymer material substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0089] As an example, the negative electrode sheet may include a negative electrode current collector and a negative electrode active material disposed on at least one surface of the negative electrode current collector.

[0090] As an example, the negative electrode current collector has two surfaces opposite each other in its own thickness direction, and the negative electrode active material is disposed on either or both of the two opposite surfaces of the negative electrode current collector.

[0091] As an example, the negative electrode active material may be a negative electrode active material known in the art for use in battery cells. As an example, the negative electrode active material may include at least one of the following materials: artificial graphite, natural graphite, soft carbon, hard carbon, silicon-based materials, tin-based materials, and lithium titanate, etc. Silicon-based materials may be selected from at least one of elemental silicon, silicon oxide compounds, silicon-carbon composites, silicon-nitrogen composites, and silicon alloys. Tin-based materials may be selected from at least one of elemental tin, tin oxide compounds, and tin alloys. However, this application is not limited to these materials, and other conventional materials that can be used as negative electrode active materials in battery cells may also be used. These negative electrode active materials may be used alone or in combination of two or more.

[0092] In some embodiments, the positive current collector can be made of aluminum, and the negative current collector can be made of copper.

[0093] In some embodiments, the separator is a separator membrane. The separator membrane can be any known porous structure separator membrane with good chemical and mechanical stability.

[0094] As an example, the material of the separator may include at least one of glass fiber, nonwoven fabric, polyethylene, polypropylene, and polyvinylidene fluoride. The separator may be a single-layer film or a multi-layer composite film. When the separator is a multi-layer composite film, the materials of each layer may be the same or different. The separator may be a separate component located between the positive and negative electrodes, or it may be attached to the surfaces of the positive and negative electrodes.

[0095] In some embodiments, the battery cell also includes an electrolyte, which acts as a conductor of ions between the positive and negative electrodes. The electrolyte can be liquid, gel-like, or solid. Liquid electrolytes include electrolyte salts and solvents.

[0096] In some embodiments, the electrolyte salt may include at least one of lithium hexafluorophosphate, lithium tetrafluoroborate, lithium perchlorate, lithium hexafluoroarsenate, lithium bis(fluorosulfonyl)imide, lithium bis(trifluoromethanesulfonyl)imide, lithium trifluoromethanesulfonate, lithium difluorophosphate, lithium difluorooxalate borate, lithium dioxalate borate, lithium difluorodioxalate phosphate, and lithium tetrafluorooxalate phosphate.

[0097] In some embodiments, the solvent may include at least one selected from ethylene carbonate, propylene carbonate, methyl ethyl carbonate, diethyl carbonate, dimethyl carbonate, dipropyl carbonate, methyl propyl carbonate, ethyl propyl carbonate, butyl carbonate, fluoroethylene carbonate, methyl formate, methyl acetate, ethyl acetate, propyl acetate, methyl propionate, ethyl propionate, propyl propionate, methyl butyrate, ethyl butyrate, 1,4-butyrolactone, sulfolane, dimethyl sulfone, methyl ethyl sulfone, and diethyl sulfone. The solvent may also be an ether solvent. Ether solvents may include one or more selected from ethylene glycol dimethyl ether, ethylene glycol diethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, 1,3-dioxolane, tetrahydrofuran, methyl tetrahydrofuran, diphenyl ether, and crown ethers.

[0098] Among them, the gel electrolyte includes a polymer as the electrolyte backbone network, combined with an ionic liquid - lithium salt.

[0099] In some implementations, the electrode assembly is a wound structure. The positive and negative electrode sheets are wound into a wound structure.

[0100] In some implementations, the electrode assembly is a stacked structure.

[0101] As an example, multiple positive and negative electrodes can be set, and multiple positive and multiple negative electrodes can be stacked alternately.

[0102] As an example, multiple positive electrode plates can be provided, and negative electrode plates can be folded to form multiple stacked folded segments, with a positive electrode plate sandwiched between adjacent folded segments.

[0103] As an example, both the positive and negative electrode plates are folded to form multiple stacked folded segments.

[0104] As an example, multiple separators can be provided, each positioned between any adjacent positive or negative electrode plates.

[0105] As an example, the separators can be continuously arranged, either by folding or rolling between any adjacent positive or negative electrode plates.

[0106] In some implementations, the electrode assembly may be flat or polygonal in shape.

[0107] In some embodiments, the electrode assembly is provided with tabs that allow current to be drawn from the electrode assembly. The tabs include a positive tab and a negative tab.

[0108] In some embodiments, the battery cell may include a housing. The housing is used to encapsulate components such as electrode assemblies and electrolytes. The housing may be made of steel, aluminum, or a composite metal (such as a copper-aluminum composite housing).

[0109] In some embodiments, the housing can be a sealed structure or a non-sealed structure. As an example, when the housing is a sealed structure, it can protect the electrode assembly and prevent, to some extent, electrolyte leakage. When the housing is a non-sealed structure, it can still protect the electrode assembly, and a sealing bag may be included between the housing and the electrode assembly to encapsulate the electrode assembly and electrolyte. Specifically, the sealing bag can be a bag-shaped insulating component or an aluminum-plastic film.

[0110] As an example, a battery cell can be a prismatic battery cell or a battery cell of other shapes. Prismatic battery cells include prismatic battery cells, blade-shaped battery cells, and multi-prismatic battery cells, such as hexagonal prismatic battery cells.

[0111] The battery device mentioned in the embodiments of this application may include one or more battery cell assemblies for providing voltage and capacity. A battery cell assembly may include multiple battery cells, which are connected in series, parallel, or mixed connections via a busbar.

[0112] In some embodiments, a battery cell assembly is typically formed by arranging multiple battery cells; as an example, a battery cell assembly can be a battery module, which is formed by arranging multiple battery cells and fixing them together to form an independent module.

[0113] As an example, a battery module can be formed by bundling multiple battery cells together with cable ties.

[0114] In some embodiments, the battery device may be a battery pack, which may include a housing and one or more individual battery cell assemblies housed within the housing.

[0115] As an example, the battery cell assembly can be a battery module, which can be housed in a housing by fixing the battery module in the housing.

[0116] As an example, battery cell assemblies can also be housed in a housing by directly fixing multiple battery cells to the housing.

[0117] As an example, the enclosure may include a first enclosure body and a second enclosure body. The first enclosure body and the second enclosure body are fastened together to form a closed space inside the enclosure to house the individual battery cells. Here, "closed" refers to covering or closing, which can be either sealed or unsealed. The first enclosure body may be a top cover or a bottom plate.

[0118] As an example, the enclosure may include a top cover, a frame, and a bottom plate. The top cover and bottom plate are connected to the frame, creating an enclosed space inside the enclosure to house the individual battery cells.

[0119] As an example, the housing can be part of the vehicle's chassis structure. For instance, the housing's roof can be at least part of the vehicle's floor, or the housing's frame can be at least part of the vehicle's crossbeams and longitudinal beams.

[0120] In some embodiments, the battery device refers to an energy storage device, which includes a housing with a door on at least one side. Energy storage devices include energy storage containers, energy storage cabinets, etc.

[0121] Currently, judging from market trends, battery applications are becoming increasingly widespread. Batteries are not only used in energy storage systems such as hydropower, thermal power, wind power, and solar power plants, but also extensively 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 battery applications, market demand is also constantly increasing.

[0122] The development of battery technology must consider multiple design factors simultaneously, such as cycle life, discharge capacity, and charge / discharge rate. However, battery performance will significantly decrease after a period of use.

[0123] In some embodiments, to improve the reliability of a battery cell, a pressure relief mechanism can generally be provided on the end cap of the battery cell's casing. In the event of thermal runaway of the battery cell, the pressure inside the battery cell can be released through the pressure relief mechanism.

[0124] A pressure relief mechanism is a component or part that is activated to release internal pressure when the internal pressure or temperature of a battery cell reaches a threshold. This threshold design varies depending on design requirements. The threshold may depend on the materials of one or more of the positive electrode, negative electrode, electrolyte, and separator in the battery cell. "Activation" as used in this application refers to the pressure relief mechanism being activated or undergoing a certain state, thereby releasing the internal pressure of the battery cell. The actions of the pressure relief mechanism may include, but are not limited to, at least a portion of the mechanism rupturing, breaking, tearing, or opening. When the pressure relief mechanism is activated, the high-temperature, high-pressure substances inside the battery cell are discharged outwards from the activated part as waste. This method allows for pressure relief of the battery cell under controllable pressure, thereby preventing potentially more serious accidents. The waste from the battery cell mentioned in the embodiments of this application includes, but is not limited to, electrolyte, dissolved or broken positive and negative electrode sheets, fragments of the separator, high-temperature, high-pressure gases generated by the reaction, and flames.

[0125] In a typical battery cell, the electrode assembly and end cap are electrically connected via a current collector, which is positioned between the electrode assembly and the end cap. To facilitate the flow of the discharge from the current collector facing the electrode assembly to a pressure relief mechanism located on the end cap in the event of thermal runaway, a pressure relief channel is provided on the current collector. However, the addition of this pressure relief channel reduces the strength of the current collector, making it insufficient to support the electrode assembly. After a period of use, the current collector deforms under the weight of the electrode assembly, significantly degrading the battery cell's performance. This deformation is particularly pronounced under vibration conditions, where the current collector experiences greater stress, deforms faster, and becomes more severe, further contributing to the significant performance reduction.

[0126] In view of this, embodiments of this application provide a battery cell, which includes a housing, an electrode assembly, a pressure relief mechanism, a current collector, and a connector. The housing has a wall, and the electrode assembly is housed within the housing. The pressure relief mechanism is disposed in the wall and configured to be actuated when the internal pressure or temperature of the battery cell reaches a threshold value to release the internal pressure of the battery cell. The current collector is disposed between the electrode assembly and the wall along a first direction and electrically connects the electrode assembly and the wall. The current collector has a pressure relief channel that extends through the current collector along the first direction. The connector is connected to the current collector and is at least partially housed within the pressure relief channel. The connector is configured to be at least partially destroyed before the pressure relief mechanism is actuated.

[0127] By incorporating a connector on the current collector and ensuring that the connector is at least partially housed within the pressure relief channel, the connector strengthens the current collector during normal battery cell operation, providing sufficient strength to support the electrode assembly and thus maintaining the battery cell's performance. When a battery cell experiences thermal runaway, the internal pressure and temperature rise, and the connector can be at least partially destroyed under the combined effects of this pressure and / or temperature. This allows the discharge from the electrode assembly-facing side of the current collector to flow rapidly through the pressure relief channel to the pressure relief mechanism, enabling rapid activation of the mechanism. This shortens the time from thermal runaway to the start of pressure relief through the mechanism, reducing the risk of battery cell explosion and fire, and effectively improving battery cell reliability.

[0128] The technical solutions described in the embodiments of this application are applicable to various electrical devices that use battery cells and battery devices, such as mobile phones, portable devices, laptops, electric vehicles, electric toys, power tools, vehicles, ships and spacecraft, etc. For example, spacecraft include airplanes, rockets, space shuttles and spacecraft.

[0129] For ease of explanation, the following embodiments will use a vehicle as an example of an electrical device.

[0130] Please refer to Figure 1 , Figure 1 This is a schematic diagram of the structure of a vehicle 1000 provided in some embodiments of this application. A battery device 100 is disposed inside the vehicle 1000, and the battery device 100 may be located at the bottom, front, or rear of the vehicle 1000. The battery device 100 can be used to power the vehicle 1000; for example, the battery device 100 can serve as the operating power source for the vehicle 1000.

[0131] The vehicle 1000 may also include a controller 200 and a motor 300. The controller 200 is used to control the battery device 100 to supply power to the motor 300, for example, for the power needs of the vehicle 1000 during startup, navigation and driving.

[0132] In some embodiments of this application, the battery device 100 can not only serve as the operating power source for the vehicle 1000, but also as the driving power source for the vehicle 1000, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000.

[0133] Please refer to Figure 2 , Figure 2 This is an exploded view of a battery device 100 provided in some embodiments of this application. The battery device 100 may include a housing 10 and battery cells 20, the housing 10 being used to house the battery cells 20.

[0134] The housing 10 has an enclosed space inside for accommodating the battery cells 20. The housing 10 can have various structures. In some embodiments, the housing 10 may include a first housing body 11 and a second housing body 12, which are interlocked. The first housing body 11 and the second housing body 12 can have various shapes, such as cuboids or cylinders. The first housing body 11 can be a hollow structure open on one side, and the second housing body 12 can also be a hollow structure open on one side. The open side of the second housing body 12 interlocks with the open side of the first housing body 11, thus forming a housing 10 with an enclosed space. Alternatively, the first housing body 11 can be a hollow structure open on one side, and the second housing body 12 can be a plate-like structure, with the second housing body 12 interlocked with the open side of the first housing body 11, thus forming a housing 10 with an accommodating chamber.

[0135] In the battery device 100, there can be one or more battery cells 20. If there are multiple battery cells 20, they can be connected in series, parallel, or in a mixed configuration. A mixed configuration means that multiple battery cells 20 are connected in both series and parallel. Alternatively, multiple battery cells 20 can be first connected in series, parallel, or in a mixed configuration to form a battery module, and then multiple battery modules can be connected in series, parallel, or in a mixed configuration to form a whole, which is then housed within the housing 10. Another option is that all battery cells 20 can be directly connected in series, parallel, or in a mixed configuration, and then the whole consisting of all battery cells 20 is housed within the housing 10.

[0136] In some embodiments, the battery device 100 may further include a busbar component, through which multiple battery cells 20 can be electrically connected to each other to achieve series, parallel, or mixed connection of the multiple battery cells 20. The busbar component may be a metallic conductor, such as copper, iron, aluminum, stainless steel, aluminum alloy, etc.

[0137] Please refer to Figure 3 , Figure 4 and Figure 5 , Figure 3 An exploded view of a battery cell 20 provided in some embodiments of this application. Figure 4 This is a schematic diagram of the connection between the current collection member 24 and the connector 25 provided in some embodiments of this application. Figure 5This is an exploded view of the current collector 24 and connector 25 provided in some embodiments of this application. Embodiments of this application provide a battery cell 20, which includes a housing 21, an electrode assembly 22, a pressure relief mechanism 23, a current collector 24, and a connector 25. The housing 21 has a wall 213, and the electrode assembly 22 is housed within the housing 21. The pressure relief mechanism 23 is disposed in the wall 213 and configured to be actuated when the internal pressure or temperature of the battery cell 20 reaches a threshold value to release the internal pressure of the battery cell 20. The current collector 24 is disposed between the electrode assembly 22 and the wall 213 along a first direction and is electrically connected to the electrode assembly 22 and the wall 213. The current collector 24 is provided with a pressure relief channel 26 that extends through the current collector 24 along the first direction. The connector 25 is connected to the current collector 24 and is at least partially housed within the pressure relief channel 26. The connector 25 is configured to be at least partially destroyed before the pressure relief mechanism 23 is actuated.

[0138] Battery cell 20 refers to the smallest unit that makes up battery device 100.

[0139] The housing 21 includes a housing 211 and an end cap 212. The housing 211 has a receiving cavity with an opening at one end for accommodating the electrode assembly 22. The end cap 212 is connected to the housing 211 and closes the opening.

[0140] End cap 212 refers to a component that covers the opening of housing 211 to isolate the internal environment of battery cell 20 from the external environment. The shape of end cap 212 can be adapted to the shape of housing 211 to fit it. Optionally, end cap 212 can be made of a material with certain hardness and strength (such as aluminum alloy), so that end cap 212 is less prone to deformation under pressure and impact, enabling battery cell 20 to have higher structural strength and improved safety performance. The material of end cap 212 can also be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and this application embodiment does not impose any special limitations on this.

[0141] The housing 211 is a component used to cooperate with the end cap 212 to form the internal environment of the battery cell 20. This internal environment can accommodate the electrode assembly 22, electrolyte, and other components. The housing 211 and the end cap 212 can be independent components. An opening can be provided on the housing 211, and the end cap 212 can be used to close the opening to form the internal environment of the battery cell 20. Alternatively, the end cap 212 and the housing 211 can be integrated. Specifically, the end cap 212 and the housing 211 can form a common mating surface before other components are inserted into the housing. When it is necessary to encapsulate the interior of the housing 211, the end cap 212 closes the housing 211. The housing 211 can have various shapes and sizes, such as cuboid or hexagonal prism. Specifically, the shape of the housing 211 can be determined according to the specific shape and size of the electrode assembly 22. The material of the housing 211 can include, but is not limited to, copper, iron, aluminum, stainless steel, aluminum alloy, and plastic.

[0142] In some embodiments, the housing 211 may have an opening at only one end, with one end cap 212 correspondingly provided. In other embodiments, the housing 211 may have openings at both ends, with two end caps 212 correspondingly provided, the two end caps 212 respectively closing the two opposite openings of the housing 211. Figure 3 In the embodiment shown, the housing 211 has an opening at only one end, and an end cap 212 is provided accordingly.

[0143] Electrode terminals 27 may also be provided on the end cap 212 or the housing 211. The electrode terminals 27 are used to electrically connect with the tabs 222 of the electrode assembly 22 to input or output electrical energy from the battery cell 20. The electrode terminals 27 and the tabs 222 are electrically connected through a current collector 24. The current collector 24 can be a metal conductor, such as copper, iron, aluminum, steel, aluminum alloy, etc.

[0144] As an example, in Figure 3 In the illustrated embodiment, the battery cell 20 is a cylindrical battery cell, the housing 211 has an opening at only one end, and there is one end cap 212 that closes the opening of the housing 211. Electrode terminals 27 are provided on the wall 213 opposite to the end cap 212. The electrode assembly 22 has tabs 222 at both opposite ends. One tab 222 of the electrode assembly 22 is a positive tab, and the other tab 222 is a negative tab. The electrode terminal 27 is electrically connected to the positive tab through a current collector 24, and the end cap 212 is electrically connected to the negative tab through another current collector 24.

[0145] Electrode assembly 22 is the component in the battery cell 20 where electrochemical reactions occur. The housing 211 may contain one or more electrode assemblies 22. The electrode assembly 22 is mainly formed by winding or stacking positive and negative electrode sheets, and typically a separator is provided between the positive and negative electrode sheets. The portions of the positive and negative electrode sheets containing active material constitute the main body 221 of the electrode assembly 22, while the portions of the positive and negative electrode sheets without active material each constitute tabs 222. The positive and negative tabs may be located together at one end of the main body or at opposite ends of the main body 221. During the charging and discharging process of the battery cell 20, the positive and negative active materials react with the electrolyte.

[0146] In an embodiment where the housing 211 has an opening at only one end, the end cap 212 can serve as the wall portion 213, or the wall of the housing 211 opposite to the end cap 212 can serve as the wall portion 213. In an embodiment where both opposite ends of the housing 211 have openings, one of the two end caps 212 serves as the wall portion 213.

[0147] The pressure relief mechanism 23 is a component used to actuate when the internal pressure or temperature of the battery cell 20 reaches a threshold, thereby releasing the internal pressure of the battery cell 20. The pressure relief mechanism 23 can be a component mounted on the wall portion 213, in which case the pressure relief mechanism 23 and the wall portion 213 are separately configured and connected. For example, the pressure relief mechanism 23 is an explosion-proof plate mounted on the wall portion 213. Alternatively, the pressure relief mechanism 23 can be part of the wall portion 213, in which case the pressure relief mechanism 23 and the wall portion 213 are integrally formed.

[0148] The pressure relief mechanism 23 includes a weak portion 231, which serves to relieve pressure. When the internal pressure or temperature of the battery cell 20 reaches a threshold, the pressure relief mechanism 23 can break along the weak portion 231 to release the internal pressure of the battery cell 20. In some embodiments, the strength of the pressure relief mechanism 23 at the weak portion 231 may be lower than the strength at other locations, so that when the internal pressure or temperature of the battery cell 20 reaches the threshold, the weak portion 231 can break under the internal pressure to release the internal pressure of the battery cell 20. In other embodiments, the melting point of the pressure relief mechanism 23 at the weak portion 231 may be lower than the melting point at other locations. Thus, when the internal pressure or temperature of the battery cell 20 reaches the threshold, the weak portion 231 can break under high temperature to release the internal pressure of the battery cell 20.

[0149] In some embodiments, the wall portion 213 is provided with a pressure relief groove 232, the bottom wall of which is the aforementioned weak portion 231. The pressure relief groove 232 can be formed by various methods, such as stamping or cold heading. By providing the pressure relief groove 232 on the wall portion 213, an integral pressure relief mechanism 23 is formed, which simplifies the forming process and improves the reliability of the pressure relief mechanism 23.

[0150] Please refer to Figure 3 The first direction is the X direction shown in the figure. When the battery cell 20 is a cylindrical battery cell, the first direction can be the axial direction of the cylindrical battery cell.

[0151] The current collector 24 is a conductive component that enables electrical connection between the electrode assembly 22 and the wall portion 213. The current collector 24 is located inside the housing 21 and is positioned between the wall portion 213 and the electrode assembly 22 along a first direction. Optionally, the current collector 24 is welded to the tab 222 of the electrode assembly 22 and to the wall portion 213 to achieve electrical connection between the electrode assembly 22 and the wall portion 213.

[0152] The current collector 24 is provided with a pressure relief channel 26, which passes through two surfaces of the current collector 24 that are arranged opposite each other in the first direction, so that the discharge from the side of the current collector 24 facing the electrode assembly 22 can reach the pressure relief mechanism 23 through the pressure relief channel 26, thereby facilitating pressure relief.

[0153] Emissions include, but are not limited to: electrolyte, dissolved or broken positive and negative electrode plates, fragments of separators, high-temperature and high-pressure gases generated by the reaction, flames, etc.

[0154] The connector 25 is connected to the manifold 24 and is at least partially housed within the pressure relief channel 26 to reinforce the manifold 24. For example, the portion of the connector 25 housed within the pressure relief channel 26 is connected to the channel wall surrounding the pressure relief channel 26. The connector 25 can be at least partially broken before the pressure relief mechanism 23 is actuated, thereby allowing the discharge from the side of the manifold 24 facing the electrode assembly 22 to flow rapidly through the pressure relief channel 26 to the pressure relief mechanism 23, enabling the pressure relief mechanism 23 to be actuated quickly.

[0155] In some embodiments, the strength of the connector 25 is lower than that of the current collector 24. When thermal runaway occurs in the battery cell 20, the connector 25 can be damaged by the internal pressure of the battery cell 20.

[0156] In other embodiments, the melting point of the connector 25 is lower than that of the current collector 24. When thermal runaway occurs in the battery cell 20, the connector 25 can be at least partially destroyed by the internal pressure and temperature of the battery cell 20.

[0157] By providing a connector 25 on the current collector 24 and having the connector 25 at least partially housed within the pressure relief channel 26, the connector 25 strengthens the current collector 24 during normal use of the battery cell 20, giving it sufficient strength to support the electrode assembly 22 and thus helping to maintain the performance of the battery cell 20. When the battery cell 20 experiences thermal runaway, the internal pressure and temperature of the battery cell 20 increase, and the connector 25 can be at least partially destroyed under the influence of the internal pressure and / or temperature of the battery cell 20. This allows the discharge from the side of the current collector 24 facing the electrode assembly 22 to flow rapidly through the pressure relief channel 26 to the pressure relief mechanism 23, enabling the pressure relief mechanism 23 to be actuated quickly. This shortens the time from thermal runaway of the battery cell 20 to the start of pressure relief through the pressure relief mechanism 23, reducing the risk of battery cell 20 explosion and fire, and effectively improving the reliability of the battery cell 20.

[0158] Please refer to Figure 3 , Figure 4 , Figure 5 , Figure 6 and Figure 7 , Figure 6 This is a schematic diagram of the structure of the first current collector 241 provided for some embodiments of this application. Figure 7 This is a top view of a first current collector 241 provided for some embodiments of this application. In some embodiments, the pressure relief channel 26 includes a plurality of sub-channels 263 arranged circumferentially along the current collector 24, and the plurality of sub-channels 263 intersect each other. The current collector 24 includes a plurality of pressure relief zones 2411. Along the circumferential direction of the current collector 24, a pressure relief zone 2411 is provided between two adjacent sub-channels 263. The connector 25 is at least partially located within the sub-channels 263 and connects the plurality of pressure relief zones 2411.

[0159] The circumferential direction of the flow collector 24 is also the direction of its outer periphery. Please refer to... Figure 6 and Figure 7 The circumferential direction of the current collection component 24 is the Y direction shown in the figure.

[0160] The pressure relief channel 26 may include two sub-channels 263, three sub-channels 263, four sub-channels 263, or more sub-channels 263, with the multiple sub-channels 263 arranged circumferentially along the collector component 24. Please refer to... Figure 6 and Figure 7 The pressure relief channel 26 in the figure includes four sub-channels 263, which are arranged circumferentially along the flow collection member 24.

[0161] Please refer to Figure 6 and Figure 7Sub-channels 263 can extend radially along the collector 24, and multiple sub-channels 263 intersect in the middle of the collector 24, that is, multiple sub-channels 263 are interconnected in the middle of the collector 24.

[0162] The current collection component 24 may include two, three, four, or more pressure relief zones 2411. These pressure relief zones 2411 are arranged circumferentially along the current collection component 24, with one pressure relief zone 2411 formed between two adjacent sub-channels 263. Please refer to... Figure 6 and Figure 7 The current collector 24 includes four pressure relief zones 2411, which are arranged circumferentially along the current collector 24. Each pressure relief zone 2411 is a portion of the enclosed area formed by the lines connecting the ends of the two sub-channels 263 near the edges of the current collector 24. When the battery cell 20 is depressurized, the pressure relief zone 2411 can be flipped open towards the pressure relief mechanism 23 around the lines connecting the ends of the two sub-channels 263 near the edges of the current collector 24, thereby opening a larger opening for pressure relief. Please refer to... Figure 6 and Figure 7 For ease of display, the line connecting the ends of the two sub-channels 263 near the edge of the collector member 24 is shown in the figure with dashed lines.

[0163] Connector 25 is partially or entirely located within subchannel 263 and connects multiple pressure relief zones 2411. In some embodiments, one connector 25 can connect all pressure relief zones 2411. In other embodiments, multiple connectors 25 can be provided, each connector 25 can connect multiple pressure relief zones 2411, ultimately connecting all pressure relief zones 2411 together.

[0164] By setting multiple sub-channels 263 that are interconnected, and a pressure relief zone 2411 between two adjacent sub-channels 263, the strength around the pressure relief zone 2411 is relatively low. When the battery cell 20 experiences thermal runaway, the connector 25 can be at least partially destroyed under the internal pressure and / or temperature of the battery cell 20. The pressure relief zone 2411 can flip open towards the pressure relief mechanism 23 under the internal pressure of the battery cell 20, thereby forming a larger opening on the current collector 24. This allows the discharge from the side of the current collector 24 facing the electrode assembly 22 to flow quickly to the pressure relief mechanism 23 through the opening, enabling the pressure relief mechanism 23 to be actuated more quickly. This further shortens the time from thermal runaway of the battery cell 20 to the start of pressure relief by the pressure relief mechanism 23, further reducing the risk of battery cell 20 explosion and fire, and effectively improving the reliability of the battery cell 20. In addition, since multiple sub-channels 263 are provided on the current collector 24 and the multiple sub-channels 263 are interconnected, the strength of the current collector 24 is further weakened. Therefore, it is necessary to provide a connector 25 to strengthen the current collector 24 so that the current collector 24 has sufficient strength to support the electrode assembly 22, thereby helping to maintain the performance of the battery cell 20.

[0165] Please refer to Figure 3 , Figure 4 , Figure 5 , Figure 6 and Figure 7 In some embodiments, along a first direction, the current collecting member 24 has a first surface 24121, and the first surface 24121 is provided with a groove 2413. A portion of the sub-channel 263 and a portion of the pressure relief area 2411 are located on the bottom wall of the groove 2413, and the portions of the multiple sub-channels 263 located on the bottom wall intersect. A portion of the connector 25 is accommodated within the sub-channel 263, and another portion of the connector 25 is accommodated within the groove 2413.

[0166] The current collector 24 has a first surface 24121 along a first direction. The first surface 24121 may be the surface of the current collector 24 facing the electrode assembly 22, or the surface of the current collector 24 facing the wall portion 213.

[0167] The first surface 24121 is provided with a groove 2413. When the first surface 24121 is the surface of the current collector 24 facing the electrode assembly 22, the groove 2413 is recessed from the first surface 24121 toward the wall portion 213.

[0168] A portion of the sub-channel 263 extends along the first direction through the bottom wall of the groove 2413, and a portion of the pressure relief area 2411 is located within the bottom wall of the groove 2413; in other words, the bottom wall of the groove 2413 includes the pressure relief area 2411. Please refer to... Figure 6 and Figure 7 The flow collection component 24 includes four pressure relief zones 2411, each of which has a portion located on the bottom wall of the groove 2413.

[0169] Multiple sub-channels 263 intersect to form a connected area, which is located on the bottom wall of the groove 2413.

[0170] "A portion of the connector 25 is accommodated within the sub-channel 263, and another portion of the connector 25 is accommodated within the groove 2413" means that a portion of the connector 25 is accommodated within the sub-channel 263, and a portion of the connector 25 that is different from the aforementioned portion is accommodated within the groove 2413. It should be noted that "another portion of the connector 25" refers to a portion different from the aforementioned "part of the connector 25." It can be any other part of the connector 25 besides the aforementioned "part of the connector 25," or it can be any of the multiple portions of the connector 25 other than the portion accommodated within the sub-channel 263.

[0171] By providing a groove 2413 on the first surface 24121, a portion of the connector 25 is accommodated within the groove 2413, which helps to reduce the height of the connector 25 protruding from the first surface 24121, thereby reducing the risk of interference between the connector 25 and other components.

[0172] Please refer to Figure 3 , Figure 4 , Figure 5 , Figure 6 , Figure 7 , Figure 8 and Figure 9 , Figure 8 A cross-sectional view of a battery cell 20 provided for some embodiments of this application. Figure 9 for Figure 8 Enlarged view of position A. In some embodiments, along a first direction, the current collecting member 24 has a second surface 24122 disposed opposite to the first surface 24121. Along the direction from the second surface 24122 to the first surface 24121, the connector 25 does not extend beyond the first surface 24121.

[0173] The current collector 24 includes a first surface 24121 and a second surface 24122, which are disposed opposite to each other along a first direction. When the first surface 24121 is the surface of the current collector 24 facing the electrode assembly 22, the second surface 24122 can be the surface of the current collector 24 facing the wall portion 213. When the first surface 24121 is the surface of the current collector 24 facing the wall portion 213, the second surface 24122 can be the surface of the current collector 24 facing the electrode assembly 22.

[0174] "The connector 25 does not extend beyond the first surface 24121 in the direction from the second surface 24122 to the first surface 24121," meaning that the connector 25 does not protrude beyond the first surface 24121 in the direction from the second surface 24122 to the first surface 24121. For example, the connector 25 has a third surface 2511 that is furthest from the wall portion 213 in the first direction. The third surface 2511 can be flush with the first surface 24121, or it can be closer to the wall portion 213 than the first surface 24121.

[0175] By ensuring that the direction of the connector 25 from the second surface 24122 to the first surface 24121 does not extend beyond the first surface 24121, that is, the direction of the connector 25 from the second surface 24122 to the first surface 24121 does not protrude from the first surface 24121, it is beneficial to reduce the risk of interference between the connector 25 and other components.

[0176] Please refer to Figure 5 , Figure 6 , Figure 7 , Figure 8 and Figure 9 In some embodiments, along the first direction, the connector 25 has a third surface 2511 that is closest to the first surface 24121, and the distance between the first surface 24121 and the third surface 2511 is H1, which satisfies: H1≥0.1mm.

[0177] The third surface 2511 is the surface of the connector 25 that is closest to the first surface 24121 along the first direction, and it is also the surface of the connector 25 that is furthest from the wall portion 213 along the first direction.

[0178] H1 represents the distance between the first surface 24121 and the third surface 2511 along the first direction. During measurement, multiple measurements can be taken and the average value can be used as H1.

[0179] The distance between the first surface 24121 and the third surface 2511 along the first direction can be: H1 = 0.1mm, 0.105mm, 0.11mm, 0.115mm, 0.12mm, 0.125mm, etc.

[0180] When H1 ≥ 0.1 mm, the distance between the first surface 24121 and the third surface 2511 along the first direction is relatively large, which helps reduce the risk of interference between the connector 25 and other components. When the first surface 24121 is the surface of the current collector 24 facing the electrode assembly 22, the large distance between the first surface 24121 and the third surface 2511 along the first direction facilitates the fit between the first surface 24121 and the tab 222 of the electrode assembly 22, thereby making it easier to weld the current collector 24 and the electrode assembly 22. In addition, because the distance between the first surface 24121 and the third surface 2511 along the first direction is relatively large, the heat generated during welding the current collector 24 and the electrode assembly 22 has a smaller impact on the connector 25.

[0181] Please refer to Figure 5 , Figure 6 , Figure 7 , Figure 8 and Figure 9 In some embodiments, the pressure relief zone 2411 includes a first portion 24111 located on the bottom wall of the groove 2413, at least one first portion 24111 being provided with a receiving portion 2414, a portion of the connector 25 being received within the receiving portion 2414.

[0182] The first part 24111 refers to the portion of the pressure relief zone 2411 located on the bottom wall of the groove 2413. Each pressure relief zone 2411 has a first part 24111, and along the circumference of the flow collecting member 24, a portion of a sub-channel 263 located on the bottom wall of the groove 2413 separates two adjacent pressure relief zones 2411.

[0183] Each pressure relief zone 2411 includes a first portion 24111, and multiple pressure relief zones 2411 include multiple first portions 24111. At least one of the multiple first portions 24111 is provided with a receiving portion 2414. The receiving portion 2414 can be a groove 2413 provided in the first portion 24111, or it can be a through hole provided in the first portion 24111. A portion of the connector 25 is received in the receiving portion 2414, thereby forming a fit with the receiving portion 2414 and improving the connection strength between the connector 25 and the first portion 24111.

[0184] Please refer to Figure 6 and Figure 7 In the embodiment shown in the figure, each first portion 24111 is provided with a receiving portion 2414.

[0185] By providing a receiving portion 2414 on the first part 24111 and housing a portion of the connector 25 within the receiving portion 2414, on the one hand, it is beneficial to increase the contact area between the connector 25 and the first part 24111, thereby improving the connection strength between the connector 25 and the first part 24111 and enhancing the reinforcing effect of the connector 25 on the current collector 24. This ensures that the current collector 24 has sufficient strength to support the electrode assembly 22, thus helping to maintain the performance of the battery cell 20. On the other hand, the connector 25 can form a limiting fit with the receiving portion 2414, thereby reducing the risk of the connector 25 moving relative to the current collector 24.

[0186] Please refer to Figure 5 , Figure 6 , Figure 7 , Figure 8 and Figure 9 In some embodiments, the receiving portion 2414 is a through hole that penetrates the first portion 24111 along a first direction.

[0187] Please refer to Figure 6 and Figure 7 In the embodiment shown in the figure, the receiving portion 2414 is a through hole, and the receiving portion 2414 penetrates the two opposing surfaces of the first portion 24111 along the first direction.

[0188] When the receiving portion 2414 is a through hole extending through the first portion 24111 along the first direction, a portion of the connector 25 can be inserted into the through hole. The contact area between the connector 25 and the first portion 24111 is large, and the connector 25 provides better reinforcement to the current collecting member 24. Furthermore, when the connector 25 is engaged with the through hole, it provides a good limiting effect, thereby reducing the risk of the connector 25 moving relative to the current collecting member 24.

[0189] Please refer to Figure 10 and Figure 11 , Figure 10 A schematic diagram of the structure of the first current collector 241 provided for other embodiments of this application. Figure 11 This is a top view of a first current collector 241 provided for other embodiments of this application. In other embodiments, the sub-channel 263 includes a first channel segment 261 disposed on the bottom wall of the groove 2413. The first channel segment 261 includes two opposing wall surfaces 2611, which are respectively located in two adjacent first portions 24111. At least one wall surface 2611 of at least one first channel segment 261 is provided with a receiving portion 2414.

[0190] Sub-channel 263 includes a first channel segment 261 and a second channel segment 262, which are connected. The first channel segment 261 is the portion of sub-channel 263 disposed on the bottom wall of groove 2413, and the second channel segment 262 is the portion of sub-channel 263 disposed outside the bottom wall of groove 2413. In other words, the first channel segment 261 is the portion of sub-channel 263 that penetrates the bottom wall of groove 2413 along a first direction, and the second channel segment 262 is the portion of sub-channel 263 that penetrates the other parts of the flow collecting member 24 along the first direction.

[0191] The first channel segment 261 includes two opposing walls 2611, one of which is located in a first part 24111 and the other is located in another first part 24111. The two first parts 24111 are arranged adjacent to each other along the circumference of the flow collecting member 24.

[0192] Each sub-channel 263 includes a first channel segment 261, and multiple sub-channels 263 include multiple first channel segments 261. Among the multiple first channel segments 261, at least one first channel segment 261 has a receiving portion 2414 on at least one wall surface 2611. Please refer to Figure 10 and Figure 11 In the embodiment shown in the figure, a receiving portion 2414 is provided on both walls 2611 of the two first channel segments 261.

[0193] When at least one wall surface 2611 of at least one first channel segment 261 is provided with a receiving portion 2414, the connector 25 has a protrusion corresponding to the receiving portion 2414. The protrusion and the receiving portion 2414 cooperate together, thereby improving the connection strength between the connector 25 and the first portion 24111, enhancing the strengthening effect of the connector 25 on the flow collecting member 24, and reducing the risk of the connector 25 moving relative to the flow collecting member 24.

[0194] Please refer to Figure 10 and Figure 11 In some embodiments, at least one first channel segment 261 has a receiving portion 2414 provided on two walls 2611.

[0195] Please refer to Figure 10 and Figure 11In the embodiment shown in the figure, there are four first channel segments 261, and two of the four first channel segments 261 have receiving portions 2414 on their two wall surfaces 2611. Of course, in other embodiments, the receiving portions 2414 may be provided on the two wall surfaces 2611 of one first channel segment 261, the two wall surfaces 2611 of three first channel segments 261, or all two wall surfaces 2611 of the first channel segments 261.

[0196] By providing receiving portions 2414 on two walls 2611 of at least one first channel segment 261, the connection strength between the connector 25 and the first portion 24111 is further enhanced, and the strengthening effect of the connector 25 on the flow collecting member 24 is further improved. At the same time, the risk of movement of the connector 25 relative to the flow collecting member 24 can be effectively limited.

[0197] Please refer to Figure 10 and Figure 11 In some embodiments, the receiving portion 2414 extends through the first portion 24111 along the first direction.

[0198] The receiving portion 2414 is disposed on the wall surface 2611, and the receiving portion 2414 penetrates the first part 24111 along the first direction, so that the receiving portion 2414 is a notch disposed in the first part 24111.

[0199] By having the receiving portion 2414 penetrate through the first part 24111 in the first direction, it is beneficial to increase the contact area between the connector 25 and the first part 24111, thereby improving the connection strength between the connector 25 and the first part 24111 and enhancing the strengthening effect of the connector 25 on the current collecting member 24.

[0200] In other embodiments, the receiving portion 2414 may be a groove 2413 provided on the wall surface 2611, and there is a distance between the two surfaces of the receiving portion 2414 and the first portion 24111 that are disposed opposite to each other along the first direction.

[0201] Please refer to Figure 12 and Figure 13 , Figure 12 This is a schematic diagram of the structure of the first current collector 241 provided for some embodiments of this application. Figure 13 This is a top view of a first current collector 241 provided for some embodiments of the present application. In some embodiments, the sub-channel 263 includes a first channel segment 261 disposed on the bottom wall of the groove 2413, and at least one first channel segment 261 includes a plurality of sub-segments 2612 connected in sequence, with the extending directions of two adjacent sub-segments 2612 intersecting.

[0202] "At least one first channel segment 261 includes a plurality of sub-segments 2612 connected in sequence, and the extension directions of two adjacent sub-segments 2612 intersect" can also be understood as: at least one first channel segment 261 includes a plurality of sub-segments 2612, and the plurality of sub-segments 2612 are connected in sequence to form a curved channel.

[0203] By including at least one first channel segment 261 as a plurality of sequentially connected sub-segments 2612, and making the extending directions of two adjacent sub-segments 2612 intersect, on the one hand, it is beneficial to increase the contact area between the connector 25 and the first portion 24111, thereby improving the connection strength between the connector 25 and the first portion 24111 and enhancing the reinforcing effect of the connector 25 on the current collecting member 24. On the other hand, the connector 25 can form a limiting fit with the plurality of sub-segments 2612, thereby reducing the risk of the connector 25 moving relative to the current collecting member 24.

[0204] Please refer to Figure 12 and Figure 13 In some embodiments, the sub-channel 263 includes a first channel segment 261 disposed on the bottom wall of the groove 2413, and the connector 25 blocks the first channel segment 261.

[0205] The connector 25 blocks all first channel segments 261, and in each first channel segment 261, the connector 25 connects two oppositely arranged walls 2611 of the first channel segment 261, thereby connecting multiple pressure relief zones 2411 together.

[0206] While sealing the first channel segment 261, the connector 25 connects the two opposing walls 2611 of the first channel segment 261, thereby connecting multiple pressure relief zones 2411. This gives the current collector 24 sufficient strength to support the electrode assembly 22, thus helping to maintain the performance of the battery cell 20. Furthermore, because the connector 25 seals the first channel segment 261, in the event of thermal runaway of the battery cell 20, the pressure on the side of the current collector 24 facing the electrode assembly 22 will rapidly increase. This allows the connector 25 to be quickly destroyed under pressure, and the pressure relief zone 2411 to flip open towards the pressure relief mechanism 23 under pressure. This creates a larger opening in the current collector 24, allowing the discharge from the side of the current collector 24 facing the electrode assembly 22 to flow quickly to the pressure relief mechanism 23, enabling the pressure relief mechanism 23 to actuate more quickly and improving the reliability of the battery cell 20.

[0207] Please refer to this again. Figure 8 and Figure 9In some embodiments, the sub-channel 263 includes a first channel segment 261 disposed on the bottom wall of the groove 2413. The connector 25 includes a first connecting portion 251, a second connecting portion 252, and a third connecting portion 253. Along a first direction, the first connecting portion 251 and the third connecting portion 253 are respectively located on opposite sides of the bottom wall of the groove 2413, and the second connecting portion 252 connects the first connecting portion 251 and the third connecting portion 253. At least a portion of the second connecting portion 252 is accommodated within the first channel segment 261.

[0208] The first connecting portion 251 and the third connecting portion 253 are the portions of the connector 25 located on both sides of the bottom surface of the groove 2413 along the first direction. Please refer to... Figure 8 and Figure 9 The first connecting portion 251 is the portion of the connector 25 located along the first direction on the side of the bottom wall of the groove 2413 away from the wall portion 213, and the second connecting portion 252 is the portion of the connector 25 located along the first direction on the side of the bottom wall of the groove 2413 facing the wall portion 213.

[0209] The second connecting portion 252 is the part of the connector 25 that connects the first connecting portion 251 and the third connecting portion 253. The second connecting portion 252 may be partially located within the first channel segment 261, or the second connecting portion 252 may be entirely located within the first channel segment 261.

[0210] The first connecting portion 251 and the third connecting portion 253 are located on both sides of the bottom wall of the groove 2413 along the first direction. The second connecting portion 252 is at least partially accommodated in the first channel section 261 and connects the first connecting portion 251 and the third connecting portion 253, so that the connector 25 is tightly connected to the multiple pressure relief areas 2411, which is beneficial to improving the strengthening effect of the current collector 24, so that the current collector 24 has sufficient strength to support the electrode assembly 22, thereby helping to maintain the performance of the battery cell 20.

[0211] Please refer to Figure 8 and Figure 9 In some embodiments, along the first direction, the minimum distance between the surface of the first connecting portion 251 facing away from the third connecting portion 253 and the surface of the third connecting portion 253 facing away from the first connecting portion 251 is H3, satisfying: 0.4mm≤H2≤1.2mm.

[0212] Along the first direction, the surface of the first connecting portion 251 that is away from the third connecting portion 253, namely the third surface 2511, and the surface of the third connecting portion 253 that is away from the first connecting portion 251, is the fourth surface.

[0213] H3 represents the minimum distance between the third surface 2511 and the fourth surface along the first direction, which is also the minimum thickness of the connector 25 along the first direction.

[0214] Along the first direction, the minimum distance between the surface of the first connecting part 251 facing away from the surface of the third connecting part 253 and the surface of the third connecting part 253 facing away from the surface of the first connecting part 251 can be: H3 = 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1mm, 1.1mm, 1.2mm, etc.

[0215] When H2 ≥ 0.4 mm, along the first direction, the minimum distance between the surface of the first connecting portion 251 and the surface of the third connecting portion 253 and the surface of the third connecting portion 253 and the surface of the first connecting portion 251 is relatively large, that is, the minimum thickness of the connector 25 is relatively large, resulting in greater strength of the connector 25. This provides better reinforcement to the current collector 24, ensuring that the current collector 24 has sufficient strength to support the electrode assembly 22, thereby helping to maintain the performance of the battery cell 20. When H2 ≤ 1.2 mm, along the first direction, the minimum distance between the surface of the first connecting portion 251 and the surface of the third connecting portion 253 and the surface of the third connecting portion 253 and the surface of the first connecting portion 251 is not too large. On the one hand, this prevents the strength of the connector 25 from being too high. When the battery cell 20 experiences thermal runaway, the connector 25 can be quickly destroyed, allowing the discharge from the side of the current collector 24 facing the electrode assembly 22 to flow quickly to the pressure relief mechanism 23 through the pressure relief channel 26, enabling the pressure relief mechanism 23 to be actuated quickly. On the other hand, the connector 25 is less likely to interfere with other components, which helps improve the reliability of the battery cell 20. Furthermore, the connector 25 occupies less internal space in the battery cell 20, which helps improve the energy density of the battery cell 20.

[0216] Please refer to Figure 8 and Figure 9 In some embodiments, the orthographic projection of the connector 25 along the first direction is circular, and the diameter of the circle is D, which satisfies: 3mm≤D≤10mm.

[0217] D represents the diameter of the orthographic projection of the connector 25 along the first direction. Figure 8 and Figure 9 In the embodiment shown, both the third surface 2511 and the fourth surface are circular. During measurement, the diameter of the third surface 2511 can be directly measured as D.

[0218] The diameter of the orthographic projection of the connector 25 along the first direction can be: D = 3mm, 4mm, 5mm, 6mm, 7mm, 8mm, 9mm, 10mm, etc.

[0219] When D ≥ 3 mm, the diameter of the circle projected by the connector 25 along the first direction is relatively large, which helps to increase the contact area between the connector 25 and the current collector 24, thus providing a better strengthening effect on the current collector 24. This ensures that the current collector 24 has sufficient strength to support the electrode assembly 22, thereby helping to maintain the performance of the battery cell 20. When D ≤ 10 mm, the diameter of the circle projected by the connector 25 along the first direction is not too large. On the one hand, when the battery cell 20 experiences thermal runaway, the connector 25 can be quickly destroyed, allowing the discharge from the side of the current collector 24 facing the electrode assembly 22 to flow quickly to the pressure relief mechanism 23 through the pressure relief channel 26, enabling the pressure relief mechanism 23 to be actuated quickly. On the other hand, the connector 25 is less likely to interfere with other components, which helps to improve the reliability of the battery cell 20. Furthermore, the connector 25 occupies less internal space in the battery cell 20, which helps to improve the energy density of the battery cell 20.

[0220] Please refer to Figure 8 and Figure 9 In some embodiments, the depth of the groove 2413 is H3, which satisfies: 0.2mm≤H3≤1.3mm.

[0221] H3 represents the depth of the groove 2413, which is the distance between the surface of the bottom wall of the groove 2413 facing away from the wall 213 and the first surface 24121 along the first direction. During measurement, multiple measurements can be taken and the average value can be used as H3.

[0222] The depth of groove 2413 can be: H3 = 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1mm, 1.1mm, 1.2mm, 1.3mm, etc.

[0223] When H3 ≥ 0.2 mm, the depth of the groove 2413 is relatively large, which can accommodate a larger connector 25, giving the connector 25 sufficient strength to effectively reinforce the current collector 24. This, in turn, ensures that the current collector 24 has sufficient strength to support the electrode assembly 22, thus helping to maintain the performance of the battery cell 20. When H3 ≤ 1.3 mm, the depth of the groove 2413 is not too large, which helps to reduce the space occupied by the current collector 24 in the first direction and improves the energy density of the battery cell 20.

[0224] Optionally, 0.2mm ≤ H3 ≤ 0.7mm.

[0225] The depth of groove 2413 can be: H3 = 0.2mm, 0.25mm, 0.3mm, 0.35mm, 0.4mm, 0.45mm, 0.5mm, 0.55mm, 0.6mm, 0.65mm, 0.7mm, etc.

[0226] When H3 ≥ 0.2 mm, the depth of the groove 2413 is relatively large, which can accommodate a larger connector 25, giving the connector 25 sufficient strength to effectively reinforce the current collector 24. This, in turn, ensures that the current collector 24 has sufficient strength to support the electrode assembly 22, thus helping to maintain the performance of the battery cell 20. When H3 ≤ 0.7 mm, the depth of the groove 2413 is not too large, which helps to reduce the space occupied by the current collector 24 in the first direction and improves the energy density of the battery cell 20.

[0227] Please refer to Figure 8 and Figure 9 In some embodiments, along the first direction, the current collecting member 24 has a second surface 24122 disposed opposite to the first surface 24121. The area of ​​the current collecting member 24 corresponding to the groove 2413 is formed with a protrusion 2415 protruding from the second surface 24122.

[0228] A groove 2413 is disposed on the first surface 24121. Specifically, the groove 2413 is recessed from the first surface 24121 toward the second surface 24122. A protrusion 2415 protrudes from the second surface 24122, and the position of the protrusion 2415 corresponds to the position of the groove 2413.

[0229] The groove 2413 can be formed on the current collecting member 24 by stamping. By stamping the groove 2413 on the first surface 24121, a protrusion 2415 protruding from the second surface 24122 can be formed accordingly. Of course, the forming method of the protrusion 2415 is not limited to this. In other embodiments, the protrusion 2415 can also be formed by casting or other processing techniques.

[0230] By deforming a portion of the current-collecting member 24 along the direction from the first surface 24121 to the second surface 24122, a groove 2413 and a protrusion 2415 are formed. On the one hand, this reduces the difficulty of forming the groove 2413. On the other hand, it allows for a larger thickness of the bottom wall of the groove 2413, resulting in a thicker portion of the pressure relief area 2411 located on the bottom wall of the groove 2413. This makes it less prone to breakage between the portion of the pressure relief area 2411 located on the bottom wall of the groove 2413 and the portion of the pressure relief area 2411 located outside the groove 2413, thereby improving the connection strength between the connector 25 and the pressure relief area 2411.

[0231] Please refer to Figure 8 and Figure 9 In some embodiments, the first surface 24121 faces the electrode assembly 22.

[0232] When the first surface 24121 is the surface of the current collector 24 facing the electrode assembly 22, by providing a groove 2413 on the first surface 24121, a portion of the connector 25 is accommodated within the groove 2413. This helps to reduce the height of the connector 25 protruding from the first surface 24121, thereby reducing the risk of interference between the connector 25 and the electrode assembly 22. Furthermore, by reducing the height of the connector 25 protruding from the first surface 24121, it is also beneficial to make the first surface 24121 and the tab 222 of the electrode assembly 22 fit together, thereby facilitating the welding of the current collector 24 and the electrode assembly 22.

[0233] In some embodiments, the melting point of the connector 25 is lower than that of the current collector 24.

[0234] By making the melting point of the connector 25 lower than that of the current collector 24, when the battery cell 20 experiences thermal runaway, the internal pressure and temperature of the battery cell 20 increase. Under the influence of the internal pressure and temperature of the battery cell 20, the connector 25 can be at least partially destroyed. This allows the discharge from the side of the current collector 24 facing the electrode assembly 22 to flow quickly to the pressure relief mechanism 23 through the pressure relief channel 26, enabling the pressure relief mechanism 23 to be actuated quickly. This shortens the time from the thermal runaway of the battery cell 20 to the start of pressure relief by the pressure relief mechanism 23, reducing the risk of the battery cell 20 exploding or catching fire, and effectively improving the reliability of the battery cell 20.

[0235] In some embodiments, the material of the connector 25 includes at least one of plastic and rubber.

[0236] Plastic and rubber materials have low strength and melting point. When the battery cell 20 experiences thermal runaway, the connector 25 is quickly destroyed under the internal pressure and temperature of the battery cell 20. This allows the discharge from the current collector 24 facing the electrode assembly 22 to flow quickly to the pressure relief mechanism 23 through the pressure relief channel 26, enabling the pressure relief mechanism 23 to be actuated quickly, which helps improve the reliability of the battery cell 20.

[0237] Optionally, the connector 25 is injection molded onto the manifold 24.

[0238] The connector 25 is manufactured by injection molding. The connector 25 is injection molded onto the manifold 24 to connect multiple pressure relief zones 2411 and to strengthen the manifold 24.

[0239] By injection molding the connector 25 onto the current collector 24, the connection strength between the connector 25 and the current collector 24 is moderate. This ensures that the current collector 24 has sufficient strength to support the electrode assembly 22 when the battery cell 20 is in normal use, thus helping to maintain the performance of the battery cell 20. Furthermore, in the event of thermal runaway in the battery cell 20, the connector 25 can be quickly destroyed, allowing the discharge from the side of the current collector 24 facing the electrode assembly 22 to flow rapidly through the pressure relief channel 26 to the pressure relief mechanism 23, enabling the pressure relief mechanism 23 to be quickly actuated.

[0240] In some embodiments, connector 25 blocks a portion of pressure relief channel 26.

[0241] A portion of the pressure relief channel 26 is blocked by the connector 25, while another portion of the pressure relief channel 26 is not blocked by the connector 25.

[0242] By blocking part of the pressure relief channel 26 with the connector 25, it is beneficial to simplify manufacturing, reduce manufacturing costs, and allow the discharge from the side of the current collector 24 facing the electrode assembly 22 to flow through the pressure relief channel 26 to the pressure relief mechanism 23 when the battery cell 20 is in normal use.

[0243] In other embodiments, connector 25 blocks the entire pressure relief channel 26.

[0244] "Connector 25 completely blocks the pressure relief channel 26" means that connector 25 completely blocks the entire pressure relief channel 26.

[0245] By blocking the entire pressure relief channel 26 with connector 25, the reinforcement effect on current collector 24 is improved, so that current collector 24 has sufficient strength to support electrode assembly 22, thereby helping to maintain the performance of battery cell 20.

[0246] Please refer to Figure 8 and Figure 9 In some embodiments, there is a gap between the connector 25 and the pressure relief mechanism 23 along the first direction.

[0247] "Along the first direction, there is a gap between the connector 25 and the pressure relief mechanism 23", that is, the connector 25 and the pressure relief mechanism 23 are not in direct contact, and there is still a certain gap between the connector 25 and the pressure relief mechanism 23.

[0248] By creating a gap between the connector 25 and the pressure relief mechanism 23 along the first direction, the connector 25 and the pressure relief mechanism 23 do not come into contact, thus minimizing the impact on the burst pressure of the pressure relief mechanism 23.

[0249] Please refer to this again. Figure 3 , Figure 4 and Figure 5 In some embodiments, the electrode assembly 22 includes a tab 222. The current collector 24 includes a first current collector 241 and a second current collector 242 connected together. The base metals of the first current collector 241 and the second current collector 242 are different, while the base metals of the first current collector 241 and the tab 222 are the same. The first current collector 241 is welded to the tab 222. The base metal of the second current collector 242 is the same as that of the wall portion 213, and the second current collector 242 is welded to the wall portion 213. A pressure relief channel 26 is disposed in the first current collector 241.

[0250] The first current collector 241 is the part of the current collector 24 that is connected to the tab 222, and the second current collector 242 is the part of the current collector 24 that is connected to the wall 213. The first current collector 241 and the second current collector 242 are connected together.

[0251] "The base metal of the second current collector 242 is different from that of the first current collector 241" means that the main components of the second current collector 242 are different from those of the first current collector 241. The main components of the first current collector 241 are those that account for more than 50% of the composition of the first current collector 241. Similarly, the main components of the second current collector 242 are those that account for more than 50% of the composition of the second current collector 242. In other words, the difference in base metal between the first current collector 241 and the second current collector 242 means that the main components of the first current collector 241 and the second current collector 242 are different. For example, if both the first current collector 241 and the second current collector 242 are made of a single material, such as copper or aluminum, then the materials of the first current collector 241 and the second current collector 242 are composed of different metallic elements. If the first current collector 241 and the second current collector 242 are made of an alloy or mixed material, such as aluminum alloy or steel, then the difference in base metal between the first current collector 241 and the second current collector 242 means that the main components of the first current collector 241 and the second current collector 242 are different, that is, the components with a content of more than 50% are different in the alloy or mixed materials. Optionally, the material of the first current collector 241 can be copper, and the material of the second current collector 242 can be steel.

[0252] The first current collector 241 and the second current collector 242 are connected, which can be achieved by means of solid-liquid combination method, solid-phase combination method, hot rolling of stacked plates, diffusion pressing method, overlay welding method, and hot rolling of overlay welding method. Specifically, the second current collector 242 is connected to the side of the first current collector 241 that is away from the electrode assembly 22.

[0253] "The base metal of the first current collector 241 and the tab 222 is the same" means that the main components of the first current collector 241 and the tab 222 are the same. Specifically, the main component of the first current collector 241 constitutes more than 50% of its composition, and similarly, the main component of the tab 222 constitutes more than 50% of its composition. The tab 222 can be made of various materials, such as copper or aluminum. If the tab 222 is a positive tab, it is usually made of aluminum, and the first current collector 241 is also primarily made of aluminum, with a content of more than 50%. If the tab 222 is a negative tab, it is usually made of copper, and the first current collector 241 is also primarily made of copper, with a content of more than 50%. In other words, the fact that the base metal of the first current collector 241 and the tab 222 is the same means that the main components of the first current collector 241 and the tab 222 are the same. For example, if the first current collector 241 and the tab 222 are both made of a single material, such as copper or aluminum, then the materials of the first current collector 241 and the tab 222 are composed of the same metallic element. If the first current collector 241 and the tab 222 are made of an alloy or mixed material, such as aluminum alloy or steel, then the fact that the base metal of the first current collector 241 and the tab 222 is the same means that the main components of the first current collector 241 and the tab 222 are the same, that is, the components with a content of more than 50% in the alloy or mixed material are the same. Optionally, the materials of the first current collector 241 and the tab 222 are both copper.

[0254] The first current collector 241 is welded to the tab 222. Since the base metals of the first current collector 241 and the tab 222 are the same, it is beneficial to improve the welding quality of the first current collector 241 and the tab 222 and improve the current carrying capacity.

[0255] "The base metal of the second current collector 242 is the same as that of the wall portion 213" means that the main components of the second current collector 242 and the wall portion 213 are the same. Specifically, the main component of the second current collector 242 constitutes 50% or more of its composition, and similarly, the main component of the wall portion 213 constitutes 50% or more of its composition. The wall portion 213 can also be made of various materials, such as copper or aluminum. If the wall portion 213 is aluminum, the main component of the second current collector 242 will also be aluminum, and its content will be 50% or more. In other words, the fact that the base metal of the second current collector 242 is the same as that of the wall portion 213 means that the main components of the second current collector 242 and the wall portion 213 are the same. For example, if the second current collector 242 and the wall portion 213 are both made of a single material, such as copper or aluminum, then the materials of the second current collector 242 and the wall portion 213 are composed of the same metallic element. If the second current collector 242 and the wall portion 213 are made of an alloy or mixed material, such as aluminum alloy or steel, then the fact that the base metal of the second current collector 242 and the wall portion 213 is the same means that the main components of the second current collector 242 and the wall portion 213 are the same, that is, the components with a content of more than 50% in the alloy or mixed material are the same. Optionally, the materials of the second current collector 242 and the wall portion 213 are both steel.

[0256] The second current collector 242 is welded to the wall portion 213. Since the base metals of the second current collector 242 and the wall portion 213 are the same, it is beneficial to improve the welding quality of the second current collector 242 and the wall portion 213 and improve the flow capacity.

[0257] By making the base metals of the first current collector 241 and the tab 222 the same, welding of the first current collector 241 and the tab 222 with the same base metal can be achieved. This mitigates the differences in melting point and thermal expansion coefficient caused by welding the first current collector 241 and the tab 222 with different base metals, thereby reducing the occurrence of welding cracks between the first current collector 241 and the tab 222 and improving the welding quality. Similarly, by making the base metals of the second current collector 242 and the wall the same, welding of the second current collector 242 and the wall with the same base metal can be achieved. This mitigates the differences in melting point and thermal expansion coefficient caused by welding the second current collector 242 and the wall with different base metals, thereby reducing the occurrence of welding cracks between the second current collector 242 and the wall and improving the welding quality between the second current collector 242 and the wall.

[0258] Please refer to Figure 3 , Figure 4 and Figure 5In some embodiments, the second current collector 242 is an annular structure and has a central hole 2421. Along the first direction, the orthographic projection of the pressure relief channel 26 is at least partially located within the central hole 2421.

[0259] The second current collector 242 has an annular structure. It can be circular, elliptical, or rectangular. The central hole 2421 is a through hole at the center of the annular structure. The orthographic projection of the pressure relief channel 26 along the first direction can be partially or entirely located within the central hole 2421.

[0260] By positioning the orthogonal projection of the pressure relief channel 26 along the first direction at least partially within the central hole 2421, it is beneficial to reduce the obstruction of the pressure relief channel 26 by the second current collector 242, and facilitate the rapid flow of the discharge from the side of the current collector 24 facing the electrode assembly 22 to the pressure relief mechanism 23 through the pressure relief channel 26.

[0261] Please refer to Figure 3 , Figure 4 and Figure 5 In some embodiments, in a projection plane perpendicular to the first direction, the orthographic projection of the second current collector 242 is disposed around the outside of the orthographic projection of the pressure relief channel 26.

[0262] The orthographic projection of the second current collector 242 in the projection plane perpendicular to the first direction is arranged around the outside of the orthographic projection of the pressure relief channel 26 in the projection plane perpendicular to the first direction. That is, the orthographic projection of the pressure relief channel 26 along the first direction is entirely located inside the central hole 2421.

[0263] By having the orthographic projection of the second current collector 242 in a projection plane perpendicular to the first direction surround the outside of the orthographic projection of the pressure relief channel 26 in a projection plane perpendicular to the first direction, the second current collector 242 is less likely to block the pressure relief channel 26, making it easier for the discharge from the side of the current collector 24 facing the electrode assembly 22 to flow quickly to the pressure relief mechanism 23 through the pressure relief channel 26.

[0264] This application embodiment also provides a battery device 100, which includes the aforementioned battery cell 20.

[0265] This application embodiment also provides an electrical device, which includes the aforementioned battery cell 20, and the battery cell 20 is used to provide electrical energy to the electrical device.

[0266] According to some embodiments of this application, please refer to Figures 3 to 13 .

[0267] This application provides a battery cell 20, which includes a housing 21, an electrode assembly 22, a pressure relief mechanism 23, a current collector 24, and a connector 25. The housing 21 has a wall 213, the electrode assembly 22 is housed within the housing 21, and the pressure relief mechanism 23 is disposed on the wall 213. The pressure relief mechanism 23 is configured to actuate when the internal pressure or temperature of the battery cell 20 reaches a threshold value to release the internal pressure of the battery cell 20. The current collector 24 is disposed between the electrode assembly 22 and the wall 213 along a first direction and is electrically connected to the electrode assembly 22 and the wall 213. The current collector 24 is provided with a pressure relief channel 26 that extends through the current collector 24 along the first direction. The connector 25 is connected to the current collector 24 and is at least partially housed within the pressure relief channel 26. The connector 25 is configured to be at least partially destroyed before the pressure relief mechanism 23 is actuated. By providing a connector 25 on the current collector 24 and having the connector 25 at least partially housed within the pressure relief channel 26, the connector 25 strengthens the current collector 24 during normal use of the battery cell 20, giving it sufficient strength to support the electrode assembly 22 and thus helping to maintain the performance of the battery cell 20. When the battery cell 20 experiences thermal runaway, the internal pressure and temperature of the battery cell 20 increase, and the connector 25 can be at least partially destroyed under the influence of the internal pressure and / or temperature of the battery cell 20. This allows the discharge from the side of the current collector 24 facing the electrode assembly 22 to flow rapidly through the pressure relief channel 26 to the pressure relief mechanism 23, enabling the pressure relief mechanism 23 to be actuated quickly. This shortens the time from thermal runaway of the battery cell 20 to the start of pressure relief through the pressure relief mechanism 23, reducing the risk of battery cell 20 explosion and fire, and effectively improving the reliability of the battery cell 20.

[0268] The pressure relief channel 26 includes multiple sub-channels 263 arranged circumferentially along the collector component 24, and the multiple sub-channels 263 intersect each other. The collector component 24 includes multiple pressure relief zones 2411, and a pressure relief zone 2411 is provided between two adjacent sub-channels 263 along the circumferential direction of the collector component 24. The connector 25 is at least partially located within the sub-channels 263 and connects the multiple pressure relief zones 2411. By setting multiple sub-channels 263 that are interconnected, and a pressure relief zone 2411 between two adjacent sub-channels 263, the strength around the pressure relief zone 2411 is relatively low. When the battery cell 20 experiences thermal runaway, the connector 25 can be at least partially destroyed under the internal pressure and / or temperature of the battery cell 20. The pressure relief zone 2411 can flip open towards the pressure relief mechanism 23 under the internal pressure of the battery cell 20, thereby forming a larger opening on the current collector 24. This allows the discharge from the side of the current collector 24 facing the electrode assembly 22 to flow quickly to the pressure relief mechanism 23 through the opening, enabling the pressure relief mechanism 23 to be actuated more quickly. This further shortens the time from thermal runaway of the battery cell 20 to the start of pressure relief by the pressure relief mechanism 23, further reducing the risk of battery cell 20 explosion and fire, and effectively improving the reliability of the battery cell 20. In addition, since multiple sub-channels 263 are provided on the current collector 24 and the multiple sub-channels 263 are interconnected, the strength of the current collector 24 is further weakened. Therefore, it is necessary to provide a connector 25 to strengthen the current collector 24 so that the current collector 24 has sufficient strength to support the electrode assembly 22, thereby helping to maintain the performance of the battery cell 20.

[0269] Along the first direction, the current collecting member 24 has a first surface 24121, and the first surface 24121 is provided with a groove 2413. A portion of the sub-channel 263 and a portion of the pressure relief area 2411 are located on the bottom wall of the groove 2413, and the portions of the multiple sub-channels 263 located on the bottom wall intersect. A portion of the connector 25 is accommodated within the sub-channel 263, and another portion of the connector 25 is accommodated within the groove 2413. By providing the groove 2413 on the first surface 24121, a portion of the connector 25 is accommodated within the groove 2413, which helps to reduce the height of the connector 25 protruding from the first surface 24121, thereby reducing the risk of interference between the connector 25 and other components.

[0270] Along the first direction, the current collecting member 24 has a second surface 24122 disposed opposite to the first surface 24121; along the direction from the second surface 24122 to the first surface 24121, the connector 25 does not extend beyond the first surface 24121. By ensuring that the connector 25 does not extend beyond the first surface 24121 along the direction from the second surface 24122 to the first surface 24121, that is, the connector 25 does not protrude from the first surface 24121 along the direction from the second surface 24122 to the first surface 24121, it is beneficial to reduce the risk of interference between the connector 25 and other components.

[0271] The pressure relief zone 2411 includes a first portion 24111 located on the bottom wall of the groove 2413. At least one first portion 24111 is provided with a receiving portion 2414, and a portion of the connector 25 is received within the receiving portion 2414. By providing the receiving portion 2414 on the first portion 24111 and having a portion of the connector 25 received within the receiving portion 2414, on the one hand, it is beneficial to increase the contact area between the connector 25 and the first portion 24111, thereby improving the connection strength between the connector 25 and the first portion 24111 and enhancing the reinforcing effect of the connector 25 on the current collector 24. This ensures that the current collector 24 has sufficient strength to support the electrode assembly 22, thus helping to maintain the performance of the battery cell 20. On the other hand, the connector 25 can form a limiting fit with the receiving portion 2414, thereby reducing the risk of the connector 25 moving relative to the current collector 24.

[0272] The melting point of connector 25 is lower than that of current collector 24. By making the melting point of connector 25 lower than that of current collector 24, when thermal runaway occurs in battery cell 20, the internal pressure and temperature of battery cell 20 increase. Connector 25 can be at least partially destroyed under the internal pressure and temperature of battery cell 20. This allows the discharge from the side of current collector 24 facing electrode assembly 22 to flow quickly to pressure relief mechanism 23 through pressure relief channel 26, enabling pressure relief mechanism 23 to be actuated quickly. This shortens the time from thermal runaway of battery cell 20 to pressure relief of battery cell 20 through pressure relief mechanism 23, reduces the risk of battery cell 20 explosion and fire, and effectively improves the reliability of battery cell 20.

[0273] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A battery cell, characterized in that, include: The outer shell has walls; Electrode assembly, housed within the housing; A pressure relief mechanism is disposed in the wall portion, and the pressure relief mechanism is configured to be actuated when the internal pressure or temperature of the battery cell reaches a threshold, so as to release the internal pressure of the battery cell; A current collector is disposed between the electrode assembly and the wall portion along a first direction and electrically connected to the electrode assembly and the wall portion. The current collector is provided with a pressure relief channel that penetrates the current collector along the first direction. A connector, connected to the current collector and at least partially housed within the pressure relief channel, is configured to be at least partially destroyed before the pressure relief mechanism is actuated.

2. The battery cell according to claim 1, characterized in that, The pressure relief channel includes multiple sub-channels, which are arranged circumferentially along the current collection component and intersect each other. The current collection component includes multiple pressure relief zones. A pressure relief zone is provided between two adjacent sub-channels along the circumferential direction of the current collection component. The connector is at least partially located within the sub-channels and connects the multiple pressure relief zones.

3. The battery cell according to claim 2, characterized in that, Along the first direction, the current collector has a first surface facing the electrode assembly, the first surface is provided with a groove, a portion of the sub-channel and a portion of the pressure relief area are located on the bottom wall of the groove, the portions of the plurality of sub-channels located on the bottom wall of the groove intersect, a portion of the connector is accommodated in the sub-channel, and another portion of the connector is accommodated in the groove.

4. The battery cell according to claim 3, characterized in that, Along the first direction, the flow collecting member has a second surface disposed opposite to the first surface; Along the direction from the second surface to the first surface, the connector does not extend beyond the first surface.

5. The battery cell according to claim 4, characterized in that, Along the first direction, the connector has a third surface that is closest to the first surface, and the distance between the first surface and the third surface is H1, which satisfies: H1≥0.1mm.

6. The battery cell according to claim 3, characterized in that, The pressure relief zone includes a first portion located on the bottom wall of the groove, at least one of the first portions being provided with a receiving portion, and a portion of the connector being received within the receiving portion.

7. The battery cell according to claim 6, characterized in that, The receiving portion is a through hole that penetrates the first part along the first direction.

8. The battery cell according to claim 6, characterized in that, The sub-channel includes a first channel segment disposed on the bottom wall of the groove. The first channel segment includes two opposing walls, which are respectively located in two adjacent first portions. At least one wall of at least one first channel segment is provided with the receiving portion, which extends through the first portion along the first direction.

9. The battery cell according to claim 3, characterized in that, The sub-channel includes a first channel segment disposed on the bottom wall of the groove, and at least one first channel segment includes a plurality of sub-segments connected in sequence, wherein the extension directions of two adjacent sub-segments intersect.

10. The battery cell according to claim 3, characterized in that, The sub-channel includes a first channel section disposed on the bottom wall of the groove, and the connector blocks the first channel section.

11. The battery cell according to claim 3, characterized in that, The sub-channel includes a first channel segment disposed on the bottom wall of the groove. The connector includes a first connecting part, a second connecting part, and a third connecting part. Along the first direction, the first connecting part and the third connecting part are respectively located on both sides of the bottom wall of the groove. The second connecting part connects the first connecting part and the third connecting part. At least a portion of the second connecting part is accommodated within the first channel segment.

12. The battery cell according to claim 3, characterized in that, Along the first direction, the flow collecting member has a second surface disposed opposite to the first surface; The area of ​​the flow collecting member corresponding to the groove has a protrusion that protrudes from the second surface.

13. The battery cell according to any one of claims 1-12, characterized in that, The melting point of the connector is lower than that of the current collector.

14. A battery device, characterized in that, Includes the battery cell according to any one of claims 1-13.

15. An electrical appliance, characterized in that, Includes a battery cell according to any one of claims 1-13, the battery cell being used to provide electrical energy to the electrical device.

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