Battery monomer and manufacturing method thereof, battery and electric equipment

Abstract

A battery cell (20) and a manufacturing method thereof, a battery (10000), and an electric device, the battery cell (20) comprising a housing (21), an electrode assembly (24), and a first electrode terminal (22), the housing (21) having a wall portion (213), the electrode assembly (24) being disposed in the housing (21), the first electrode terminal (22) being disposed on the wall portion (213); the first electrode terminal (22) comprises a first terminal part (221) and a second terminal part (222), the first terminal part (221) and the second terminal part (222) are made of different materials, and the first terminal part (221) and the second terminal part (222) are stacked in the thickness direction of the wall part (213); wherein the first terminal part (221) is provided with a connecting part (223), the second terminal part (222) is provided with a hole part (2222), and the connecting part (223) is at least partially arranged in the hole part (2222) and is fixedly connected with the second terminal part (222), so that the first terminal part (221) and the second terminal part (222) have relatively high connecting strength, the risk of separation of the first terminal part (221) and the second terminal part (222) is reduced, and the reliability of the connector is improved. And the reliability of the battery cells (20) can be improved.

Description

Battery cells and their manufacturing methods, batteries and electrical equipment

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

[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 battery life, energy density, discharge capacity, and charge / discharge rate. Furthermore, battery reliability must also be considered. However, current batteries have relatively poor reliability.

[0003] Summary of the Invention

[0004] The purpose of this application is to provide a battery cell and its manufacturing method, a battery and an electrical device, which aims to improve the problem of poor battery reliability in related technologies.

[0005] In a first aspect, embodiments of this application provide a battery cell, the battery cell including a housing, an electrode assembly, and a first electrode terminal, the housing having a wall portion; the electrode assembly being disposed within the housing; the first electrode terminal being disposed on the wall portion, the first electrode terminal including a first terminal portion and a second terminal portion, the first terminal portion and the second terminal portion being made of different materials, the first terminal portion and the second terminal portion being stacked along the thickness direction of the wall portion; wherein, the first terminal portion is provided with a connecting portion, the second terminal portion is provided with a hole portion, the connecting portion being at least partially disposed in the hole portion and fixedly connected to the second terminal portion.

[0006] In the above technical solution, the first terminal portion and the second terminal portion of the first electrode terminal are made of different materials, which facilitates the welding of one of the first terminal portion and the second terminal portion to the first electrode lead-out portion, and the welding of the other of the first terminal portion and the second terminal portion to the busbar component. In addition, the first terminal portion is provided with a connecting portion, and the second terminal portion is provided with a hole portion. The connecting portion is at least partially provided in the hole portion and is fixedly connected to the second terminal portion, so that the first terminal portion and the second terminal portion have high connection strength, reducing the risk of separation of the first terminal portion and the second terminal portion, and helping to improve the reliability of the battery cell.

[0007] As an optional technical solution in this application embodiment, the connecting part includes a connecting body and a limiting body. The connecting body is at least partially accommodated in the hole. Along the thickness direction of the wall, the first terminal part and the limiting body are respectively connected to both ends of the connecting body, and at least a portion of the second terminal part is clamped between the first terminal part and the limiting body.

[0008] In the above technical solution, the connector is inserted into the hole, and the first terminal and the limiting body are respectively connected to the two ends of the connector and cooperate to clamp the second terminal, so that the connector cannot detach from the hole along the thickness direction of the wall, so that the first terminal and the second terminal can be tightly connected, reducing the risk of separation of the first terminal and the second terminal, which is beneficial to improving the reliability of the battery cell.

[0009] As an optional technical solution in this application embodiment, the hole includes a first hole segment and a second hole segment arranged along the thickness direction of the wall. The diameter of the second hole segment is larger than the diameter of the first hole segment. The hole wall surfaces of the first hole segment and the second hole segment are connected by a stepped surface. The connecting body passes through the first hole segment, and the limiting body is at least partially located in the second hole segment and abuts against the stepped surface.

[0010] In the above technical solution, the hole is a stepped hole. By at least partially placing the limiting body within the second hole segment, the volume of the limiting body extending out of the second hole segment in the direction away from the connector can be reduced, thus reducing the space occupied inside the battery and improving the battery's energy density. Furthermore, since the volume of the limiting body extending out of the second hole segment in the direction away from the connector is small, it also facilitates welding the second terminal portion to the busbar component.

[0011] As an optional technical solution in this application embodiment, along the thickness direction of the wall portion, the second terminal portion has a first surface opposite to the first terminal portion, and the second hole segment extends to the first surface.

[0012] In the above technical solution, when the second hole extends to the first surface, the hole is a through hole that penetrates the second terminal part along the thickness direction of the wall part, which makes it more convenient to fix the connecting part and the second terminal part together.

[0013] As an optional technical solution in this application embodiment, along the thickness direction of the wall portion, the second terminal portion has a first surface that is opposite to the first terminal portion, and the second hole segment is at a distance from the first surface.

[0014] In the above technical solution, when there is a distance between the second hole segment and the first surface, the hole is a blind hole provided in the second terminal portion. In this way, the area of ​​the first surface can be larger, which facilitates the welding of the second terminal portion to the bus component or the first electrode lead-out portion.

[0015] As an optional technical solution in this application embodiment, the limiting body is completely accommodated within the second hole segment.

[0016] In the above technical solution, when the limiting body is completely contained within the second hole section, the limiting body occupies less internal space of the battery, which is more conducive to improving the energy density of the battery and facilitates the welding of the second terminal part to the bus component or the first electrode lead-out part.

[0017] As an optional technical solution in this application embodiment, along the thickness direction of the wall portion, the second terminal portion has a first surface that is opposite to the first terminal portion, and the limiting body has a second surface that is opposite to the connecting body, the second surface being closer to the first terminal portion than the first surface.

[0018] In the above technical solution, by making the second surface closer to the first terminal portion than the first surface, the limiting body is less likely to interfere with the welding when welding the second terminal portion and the bus component or the second terminal portion and the first electrode lead-out portion, thereby making the welding of the second terminal portion to the bus component or the first electrode lead-out portion simpler and more convenient.

[0019] As an optional technical solution in this application embodiment, along the thickness direction of the wall portion, the second terminal portion has a first surface that is opposite to the first terminal portion, and the connecting portion has a second surface that is opposite to the first terminal portion, the second surface being closer to the first terminal portion than the first surface.

[0020] In the above technical solution, by making the second surface closer to the first terminal portion than the first surface, the connection portion is less likely to interfere with the welding when welding the second terminal portion and the bus component or the second terminal portion and the first electrode lead-out portion, thereby making the welding of the second terminal portion to the bus component or the first electrode lead-out portion simpler and more convenient.

[0021] As an optional technical solution in this application embodiment, along the thickness direction of the wall portion, the first terminal portion has a third surface facing the second terminal portion, the second terminal portion has a fourth surface facing the first terminal portion, the third surface and the fourth surface are connected; the connecting portion is disposed on the third surface, and the hole portion penetrates the fourth surface.

[0022] In the above technical solution, the connection between the third and fourth surfaces is beneficial to further improve the connection strength between the first and second terminal portions. By setting the connecting portion on the third surface and the hole penetrating the fourth surface, the connection force between the connecting portion and the second terminal portion helps to maintain a tight connection at the interface formed by the connection between the third and fourth surfaces, reducing the risk of loosening of the connection interface, which in turn helps to reduce the internal resistance of the first electrode terminal and improve the reliability of the battery cell.

[0023] As an optional technical solution in this application embodiment, the first terminal portion is provided with a first groove, the second terminal portion is at least partially accommodated in the first groove, and the bottom surface of the first groove is the third surface.

[0024] In the above technical solution, by providing a first groove on the first terminal portion and at least partially accommodating the second terminal portion within the first groove, the first groove serves a positioning function, thereby facilitating the connection between the first terminal portion and the second terminal portion. Furthermore, the bottom surface of the first groove is a third surface, making it more difficult for the electrolyte to penetrate the connection interface formed by the third and fourth surfaces, further reducing the risk of metal corrosion caused by the electrolyte penetrating the connection interface.

[0025] As an optional technical solution in this application embodiment, the peripheral surface of the connecting part is connected to the hole wall surface of the hole part.

[0026] In the above technical solution, when the peripheral surface of the connecting part is connected to the hole wall surface of the hole, the connecting part and the second terminal part have a large connection surface, which is beneficial to make the first terminal part and the second terminal part have a high connection strength, reduce the risk of separation of the first terminal part and the second terminal part, and improve the reliability of the battery cell.

[0027] As an optional technical solution in this application embodiment, the first terminal portion and the second terminal portion are friction welded.

[0028] In the above technical solution, friction welding is used to connect the first terminal and the second terminal. This results in stable welding quality and high connection strength between the first and second terminal portions after welding, which helps reduce the risk of separation between them and improves the reliability of the battery cell. Furthermore, friction welding the first and second terminal portions after the connection is fixedly connected further enhances the connection strength, further reduces the risk of separation, and improves the reliability of the battery cell.

[0029] As an optional technical solution in this application embodiment, along the first direction, the distance between the axis of the connecting part and the axis of the second terminal part is L, and the minimum diameter of the second terminal part is D, satisfying: L / D≤0.1; the first direction is perpendicular to the thickness direction of the wall part.

[0030] In the above technical solution, when L / D≤0.1, the axis of the connecting part and the axis of the second terminal part are basically coincident, which facilitates the friction welding of the first terminal part and the second terminal part.

[0031] As an optional technical solution in this application embodiment, the axis of the connecting part coincides with the axis of the second terminal part.

[0032] In the above technical solution, when the axis of the connecting part and the axis of the second terminal part coincide, the friction welding of the first terminal part and the second terminal part is simpler and more convenient, and the welding quality is higher.

[0033] As an optional technical solution in this application embodiment, along the thickness direction of the wall portion, the second terminal portion is disposed on the side of the first terminal portion away from the interior of the housing.

[0034] In the above technical solution, the first terminal portion is closer to the inside of the housing than the second terminal portion, which facilitates the welding of the first terminal portion to the first electrode lead-out portion and the welding of the second terminal portion to the bus component.

[0035] As an optional technical solution in this application embodiment, the battery cell further includes a sealing member, which is at least partially disposed between the first terminal portion and the wall portion.

[0036] In the above technical solution, the sealing element seals the first terminal portion and the wall portion, which can reduce the risk of electrolyte seeping into the space between the first terminal portion and the second terminal portion, causing metal corrosion.

[0037] As an optional technical solution of this application embodiment, the first terminal portion is provided with a first groove on the side away from the inside of the housing, and the second terminal portion is at least partially accommodated in the first groove; along the thickness direction of the wall portion, the bottom surface of the first groove is a third surface, the second terminal portion has a fourth surface facing the first terminal portion, and the third surface and the fourth surface are connected; the sealing member is at least partially disposed between the groove sidewall of the first groove and the wall portion.

[0038] In the above technical solution, by providing a first groove on the first terminal portion and at least partially accommodating the second terminal portion within the first groove, the first groove serves a positioning function, thereby facilitating the connection between the first terminal portion and the second terminal portion. Furthermore, the sealing element is disposed between the groove sidewall and the wall portion of the first groove, making it more difficult for the electrolyte to penetrate into the connection interface formed by the connection of the third and fourth surfaces, further reducing the risk of metal corrosion caused by electrolyte penetration into the connection interface.

[0039] As an optional technical solution in this application embodiment, the wall portion is provided with an outlet hole, and the sealing member is at least partially located in the outlet hole; the battery cell includes a first insulating member, the first insulating member is disposed on the side of the wall portion facing the interior of the outer casing, and the first insulating member abuts against the sealing member; and / or the battery cell includes a second insulating member, the second insulating member is at least partially disposed between the first electrode terminal and the wall portion, and the second insulating member abuts against the sealing member.

[0040] In the above technical solution, by providing a first insulating member, the wall portion and the electrode assembly are insulated and isolated, reducing the risk of short circuit due to contact between the wall portion and the electrode assembly. A second insulating member insulates and isolates the first electrode terminal from the wall portion, reducing the risk of short circuit due to contact between the first electrode terminal and the wall portion. Furthermore, the first and second insulating members abut against both sides of the sealing member along the thickness direction of the wall portion, respectively, which can limit the sealing member, keeping it within the lead-out hole and ensuring a stable seal between the first terminal portion and the wall portion, further reducing the risk of metal corrosion caused by electrolyte seeping into the composite interface of the first and second terminal portions.

[0041] As an optional technical solution in this application embodiment, along the thickness direction of the wall portion, a portion of the first insulating member is clamped between the first terminal portion and the wall portion.

[0042] In the above technical solution, by clamping a portion of the first insulating member between the first terminal portion and the wall portion, the first terminal portion and the wall portion cooperate to limit the first insulating member, so that the first insulating member can stably abut against the sealing member, and the sealing member stably seals the first terminal portion and the wall portion.

[0043] As an optional technical solution in this application embodiment, the surface of the wall portion facing the inside of the housing is provided with a second groove, the lead-out hole communicates with the second groove, and the first insulating member includes an insulating portion accommodated in the second groove, the insulating portion being clamped between the first terminal portion and the wall portion.

[0044] In the above technical solution, by accommodating the insulating part in the second groove and clamping the insulating part with the first terminal part and the wall part, the occupancy of the insulating part on the internal space of the battery cell can be reduced, thereby helping to improve the energy density of the battery cell.

[0045] As an optional technical solution in this application embodiment, the second insulating member is disposed around the second terminal portion, and a third groove is provided on the outer peripheral surface of the second terminal portion, and the second insulating member is partially accommodated in the third groove.

[0046] In the above technical solution, by providing a third groove on the outer peripheral surface of the second terminal portion and accommodating the second insulating part within the third groove, the second insulating part can limit the second terminal portion along the radial direction of the lead-out hole.

[0047] As an optional technical solution in this application embodiment, the surface of the wall portion facing away from the interior of the outer shell is provided with a limiting protrusion, and the second insulating member is provided with a fourth groove, wherein the limiting protrusion is at least partially accommodated in the fourth groove.

[0048] In the above technical solution, by setting a limiting protrusion on the surface of the wall away from the inside of the outer shell, and setting a fourth groove on the second insulating member to cooperate with the limiting protrusion, a better limiting effect can be achieved on the second insulating member.

[0049] As an optional technical solution in this application embodiment, the second insulating member is an injection molded part formed between the wall portion and the first electrode terminal.

[0050] In the above technical solution, by injection molding a second insulating component between the wall and the first electrode terminal, the second insulating component can limit the first electrode terminal and enhance the connection strength between the first electrode terminal and the wall.

[0051] As an optional technical solution in this application embodiment, the wall portion is provided with a lead-out hole, and the first terminal portion and / or the second terminal portion are at least partially accommodated in the lead-out hole.

[0052] In the above technical solution, by at least partially accommodating the first terminal portion and / or the second terminal portion within the lead-out hole, the occupation of the first terminal portion and / or the second terminal portion on the internal space of the battery cell or the internal space of the battery can be reduced, which is beneficial to improving the energy density of the battery cell or the battery.

[0053] As an optional technical solution in this application embodiment, a portion of the first terminal portion is accommodated in the lead-out hole, and another portion of the first terminal portion protrudes from the surface of the wall portion facing the interior of the housing in a direction facing the interior of the housing; and / or a portion of the second terminal portion is accommodated in the lead-out hole, and another portion of the second terminal portion protrudes from the surface of the wall portion facing away from the interior of the housing in a direction away from the interior of the housing.

[0054] In the above technical solution, a portion of the first terminal is housed within the lead-out hole, which reduces the space occupied by the battery cell and increases the energy density of the battery cell. Another portion of the first terminal protrudes from the surface of the wall facing the interior of the casing, facilitating welding of the first terminal to the first electrode lead-out portion. A portion of the second terminal is housed within the lead-out hole, which reduces the space occupied by the battery cell and increases the energy density of the battery. Another portion of the second terminal protrudes from the surface of the wall facing away from the interior of the casing, facilitating welding of the second terminal to the busbar component.

[0055] Secondly, embodiments of this application also provide a method for manufacturing a battery cell, the method comprising: step S100: manufacturing a first electrode terminal; step S200: providing a housing having a wall portion; step S300: mounting the first electrode terminal onto the wall portion; wherein, step S100 comprises: step S110: providing a first terminal portion and a second terminal portion, the first terminal portion having a connecting portion and the second terminal portion having a hole portion; step S120: inserting the connecting portion into the hole portion; step S130: fixing the connecting portion to the second terminal portion.

[0056] As an optional technical solution in this application embodiment, after step S120, the battery cell manufacturing method further includes: step S121: connecting the first terminal portion and the second terminal portion.

[0057] In the above technical solution, on the basis of the fixed connection between the connecting part and the second terminal part, the first terminal part and the second terminal part are then connected, which is beneficial to further improve the connection strength between the first terminal part and the second terminal part, further reduce the risk of separation between the first terminal part and the second terminal part, and improve the reliability of the battery cell.

[0058] As an optional technical solution in an embodiment of this application, step S121 includes: step S1211: friction welding the first terminal portion and the second terminal portion.

[0059] In the above technical solution, the first terminal and the second terminal are combined by friction welding. The welding quality is stable and the connection strength of the first terminal and the second terminal after welding is high. This helps to reduce the risk of separation between the first terminal and the second terminal and improves the reliability of the battery cell.

[0060] As an optional technical solution in an embodiment of this application, step S130 includes: step S131: riveting the connecting part to the second terminal part.

[0061] In the above technical solution, the connection part and the second terminal part are fixed by riveting the connection part and the second terminal part, so that the first terminal part and the second terminal part have high connection strength, reducing the risk of separation of the first terminal part and the second terminal part, which is conducive to improving the reliability of the battery cell.

[0062] As an optional technical solution of this application embodiment, the connecting part includes a connecting body and a limiting body, the first terminal part and the limiting body are respectively connected to the two ends of the connecting body, and the step S130 includes: step S132: friction welding the first terminal part and the second terminal part, so that a part of the second terminal part is squeezed between the first terminal part and the limiting body, so that a part of the second terminal part is clamped between the first terminal part and the limiting body.

[0063] In the above technical solution, the connecting part is prefabricated as a structure with a connecting body and a limiting body, and the connecting part is accommodated in the hole. During the friction welding of the first terminal part and the second terminal part, the second terminal part is partially squeezed between the first terminal part and the limiting body, so that the second terminal part can be clamped between the first terminal part and the limiting body. This achieves both the fixed connection of the connecting part and the second terminal part and the friction welding of the first terminal part and the second terminal part, resulting in a high connection strength between the first terminal part and the second terminal part, reducing the risk of separation between the first terminal part and the second terminal part, and improving the reliability of the battery cell.

[0064] As an optional technical solution in this application embodiment, step S130 includes: step S133: connecting the peripheral surface of the connecting part to the hole wall surface of the hole part.

[0065] In the above technical solution, when the peripheral surface of the connecting part is connected to the hole wall surface of the hole, the connecting part and the second terminal part have a large connection surface, which is beneficial to make the first terminal part and the second terminal part have a high connection strength, reduce the risk of separation of the first terminal part and the second terminal part, and improve the reliability of the battery cell.

[0066] As an optional technical solution in this application embodiment, the wall portion is provided with a lead-out hole; step S300 includes: step S310: a sealing member is sleeved on the outside of the first terminal portion; step S320: a first insulating member is provided on the side of the wall portion facing the inside of the housing; step S330: the first electrode terminal is inserted into the lead-out hole, and the first terminal portion presses part of the first insulating member against the wall portion; step S340: a second insulating member is injection molded between the second terminal portion and the wall portion, so that the first insulating member and the second insulating member respectively abut against both sides of the sealing member.

[0067] In the above technical solution, by providing a first insulating member, the wall portion and the electrode assembly are insulated and isolated, reducing the risk of short circuit due to contact between the wall portion and the electrode assembly. A second insulating member insulates and isolates the first electrode terminal from the wall portion, reducing the risk of short circuit due to contact between the first electrode terminal and the wall portion. Furthermore, the first and second insulating members abut against both sides of the sealing member along the thickness direction of the wall portion, respectively, which can limit the sealing member, keeping it within the lead-out hole and ensuring a stable seal between the first terminal portion and the wall portion, further reducing the risk of metal corrosion caused by electrolyte seeping into the composite interface of the first and second terminal portions.

[0068] Thirdly, embodiments of this application also provide a battery, the battery comprising the aforementioned battery cell.

[0069] Fourthly, embodiments of this application also provide an electrical device, the electrical device including the aforementioned battery cell, the battery cell being used to provide electrical energy to the electrical device.

[0070] 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.

[0071] Figure 1 is a structural schematic diagram of a vehicle provided in some embodiments of this application;

[0072] Figure 2 is an exploded view of a battery provided in some embodiments of this application;

[0073] Figure 3 is a schematic diagram of the structure of a battery cell provided in some embodiments of this application;

[0074] Figure 4 is an exploded view of a single battery cell provided in some embodiments of this application;

[0075] Figure 5 is a schematic diagram of the wall structure provided in some embodiments of this application;

[0076] Figure 6 is a top view of the wall portion provided in some embodiments of this application;

[0077] Figure 7 is a cross-sectional view of position AA in Figure 6;

[0078] Figure 8 is an enlarged view of position B in Figure 7;

[0079] Figure 9 is a schematic diagram of the structure of the first electrode terminal provided in some embodiments of this application;

[0080] Figure 10 is an exploded view of the first electrode terminal provided in some embodiments of this application;

[0081] Figure 11 is a cross-sectional view of the wall portion provided in some other embodiments of this application;

[0082] Figure 12 is a cross-sectional view of the wall portion provided in some embodiments of this application;

[0083] Figure 13 is a schematic block diagram of a battery cell manufacturing method provided in some embodiments of this application;

[0084] Figure 14 is a schematic block diagram of a battery cell manufacturing method provided in some other embodiments of this application;

[0085] Figure 15 is a schematic block diagram of a battery cell manufacturing method provided in some embodiments of this application;

[0086] Figure 16 is a schematic block diagram of a battery cell manufacturing method provided in some embodiments of this application;

[0087] Figure 17 is a schematic block diagram of a battery cell manufacturing method provided in some embodiments of this application;

[0088] Figure 18 is a cross-sectional view of the connecting portion and the second terminal portion before riveting according to some embodiments of this application;

[0089] Figure 19 is a cross-sectional view of the connecting portion and the second terminal portion after riveting according to some embodiments of this application;

[0090] Figure 20 is a schematic block diagram of a battery cell manufacturing method provided in some other embodiments of this application;

[0091] Figure 21 is a cross-sectional view of the first terminal portion and the second terminal portion before friction welding according to some embodiments of this application;

[0092] Figure 22 is a cross-sectional view of the first terminal portion and the second terminal portion after friction welding according to some embodiments of this application;

[0093] Figure 23 is a schematic block diagram of a battery cell manufacturing method provided in some other embodiments of this application;

[0094] Figure 24 is a cross-sectional view of a first electrode terminal provided in some embodiments of this application;

[0095] Figure 25 is a schematic block diagram of a battery cell manufacturing method provided in some other embodiments of this application.

[0096] Icons: 10-Box body; 11-First part; 12-Second part; 20-Battery cell; 21-Outer casing; 211-Housing shell; 212-End cap; 213-Wall; 2131-Lead-out hole; 2132-Second groove; 2133-Limiting protrusion; 22-First electrode terminal; 221-First terminal part; 2211-First groove; 22111-Third surface; 22112-Slot sidewall; 222-Second terminal part; 2221-Third groove; 2222-Hole part; 22221-First hole segment; 22222-Second hole segment; 22223-Stepped surface; 2223-Fourth groove; 22 24-Fourth surface; 2225-First surface; 223-Connecting part; 2231-Connecting body; 2232-Limiting body; 22321-Second surface; 23-Second electrode terminal; 24-Electrode assembly; 241-Main body; 242-First electrode lead-out part; 2421-First electrode tab; 2422-First current collector; 243-Second electrode lead-out part; 2431-Second electrode tab; 2432-Second current collector; 25-First insulating member; 251-Insulating part; 26-Second insulating member; 27-Sealing member; 100-Battery; 200-Controller; 300-Motor; 1000-Vehicle.

[0097] 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.

[0098] 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.

[0099] 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.

[0100] 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.

[0101] 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.

[0102] 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.

[0103] In this application, "multiple" means two or more (including two).

[0104] 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.

[0105] The battery cell can be a lithium-ion battery, sodium-ion battery, sodium-lithium-ion battery, lithium metal battery, sodium metal battery, lithium-sulfur battery, magnesium-ion battery, nickel-metal hydride battery, nickel-cadmium battery, lead-acid battery, etc., and the embodiments of this application are not limited to this.

[0106] 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, helps prevent short circuits to some extent while allowing active ions to pass through.

[0107] In some embodiments, the positive electrode can be a positive electrode sheet, which may include a positive current collector and a positive active material disposed on at least one surface of the positive current collector.

[0108] 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.

[0109] 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.).

[0110] 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 battery positive electrode active materials 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 / 3 Mn 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 0.05At least one of O2 and its modified compounds.

[0111] 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.

[0112] In some embodiments, the negative electrode can be a negative electrode sheet, and the negative electrode sheet can include a negative current collector.

[0113] 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 silver-treated aluminum or stainless steel, stainless steel, copper, aluminum, nickel, carbon electrode, nickel, or titanium, etc. Foamed metal can be foamed nickel, foamed copper, foamed aluminum, foamed 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.).

[0114] As an example, the negative electrode sheet may include a negative current collector and a negative active material disposed on at least one surface of the negative current collector.

[0115] 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.

[0116] 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 battery negative electrode active materials may also be used. These negative electrode active materials may be used alone or in combination of two or more.

[0117] In some embodiments, the positive current collector can be made of aluminum, and the negative current collector can be made of copper.

[0118] In some embodiments, the electrode assembly further includes an isolator disposed between the positive and negative electrodes.

[0119] In some embodiments, the separator is a separator membrane. The separator membrane can be of various types, and any known porous separator membrane with good chemical and mechanical stability can be selected.

[0120] 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.

[0121] In some embodiments, the separator is a solid electrolyte. The solid electrolyte is disposed between the positive and negative electrodes, serving both to transport ions and to isolate the positive and negative electrodes.

[0122] 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.

[0123] 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.

[0124] 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.

[0125] Among them, the gel electrolyte includes a polymer as the electrolyte backbone network, combined with an ionic liquid - lithium salt.

[0126] Solid electrolytes include polymer solid electrolytes, inorganic solid electrolytes, and composite solid electrolytes.

[0127] As an example, polymer solid electrolytes can be polyether (polyoxyethylene), polysiloxane, polycarbonate, polyacrylonitrile, polyvinylidene fluoride, polymethyl methacrylate, monoionic polymers, polyionic liquids-lithium salts, cellulose, etc.

[0128] As an example, inorganic solid electrolytes may include one or more of the following: oxide solid electrolytes (crystalline perovskite, sodium superconducting ion conductor, garnet, amorphous LiPON thin film), sulfide solid electrolytes (crystalline lithium superconducting ion conductor (lithium germanium phosphate sulfide, silver sulfide germanium ore), amorphous sulfides), halide solid electrolytes, nitride solid electrolytes, and hydride solid electrolytes.

[0129] As an example, composite solid electrolytes are formed by adding inorganic solid electrolyte fillers to polymer solid electrolytes.

[0130] In some implementations, the electrode assembly is a wound structure. The positive and negative electrode sheets are wound into a wound structure.

[0131] In some implementations, the electrode assembly is a stacked structure.

[0132] As an example, multiple positive and negative electrode plates can be set, and multiple positive and multiple negative electrode plates can be stacked alternately.

[0133] As an example, multiple positive electrode sheets can be set, and negative electrode sheets are folded to form multiple stacked folded segments, with a positive electrode sheet sandwiched between adjacent folded segments.

[0134] As an example, both the positive and negative electrode sheets are folded to form multiple stacked folded segments.

[0135] As an example, multiple separators can be provided, each positioned between any adjacent positive or negative electrode plates.

[0136] As an example, the separator can be set continuously, either by folding or rolling between any adjacent positive or negative electrode plates.

[0137] In some embodiments, the electrode assembly can be cylindrical, flat, or polygonal, etc.

[0138] In some embodiments, the electrode assembly has tabs that allow current to be drawn from the electrode assembly. The tabs include a positive tab and a negative tab.

[0139] 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, plastic (such as polypropylene), composite metal (such as copper-aluminum composite), or aluminum-plastic film, etc.

[0140] 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.

[0141] As an example, a battery cell can be a cylindrical battery cell, a prismatic battery cell, a pouch battery cell, or a battery cell of other shapes. Prismatic battery cells include, but are not limited to, square battery cells, blade-shaped battery cells, and multi-prismatic batteries, such as hexagonal prismatic batteries.

[0142] The battery mentioned in the embodiments of this application refers to a single physical module comprising one or more battery cells to provide higher voltage and capacity.

[0143] In some embodiments, the battery can be a battery module, and when there are multiple battery cells, the multiple battery cells are arranged and fixed to form a battery module.

[0144] In some embodiments, the battery can be a battery pack, which includes a housing and individual battery cells, with the individual battery cells or battery modules housed within the housing.

[0145] In some embodiments, the housing may be part of the vehicle's chassis structure. For example, a portion of the housing may be at least a part of the vehicle's floor, or a portion of the housing may be at least a part of the vehicle's crossbeams and longitudinal beams.

[0146] In some embodiments, the battery can be an energy storage device. Energy storage devices include energy storage containers, energy storage cabinets, etc.

[0147] 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.

[0148] The development of battery technology must consider multiple design factors simultaneously, such as battery life, energy density, discharge capacity, and charge / discharge rate. Additionally, battery reliability must also be considered. However, current batteries have relatively poor reliability.

[0149] For typical batteries, the negative electrode tab and the current collector are made of different materials. For example, the negative electrode tab is usually made of copper, while the current collector is usually made of aluminum. To reduce the difficulty of welding the electrode terminals to the negative electrode tab and the electrode terminals to the current collector, the existing technology generally combines two terminal parts of different materials to form an electrode terminal. One terminal part is made of the same material as the negative electrode tab and is used for welding to the negative electrode tab, while the other terminal part is made of the same material as the current collector and is used for welding to the current collector.

[0150] However, the connection strength between the two terminals is poor, and the two terminals are prone to separation when subjected to external force. For example, when the busbar pulls on the terminal it is connected to, the two terminals are likely to separate, resulting in poor battery reliability.

[0151] Therefore, this application provides a battery cell, which includes a housing, an electrode assembly, and a first electrode terminal. The housing has a wall portion, the electrode assembly is disposed within the housing, and the first electrode terminal is disposed on the wall portion. The first electrode terminal includes a first terminal portion and a second terminal portion, which are made of different materials and are stacked along the thickness direction of the wall portion. The first terminal portion has a connecting portion, and the second terminal portion has a hole portion. The connecting portion is at least partially disposed in the hole portion and is fixedly connected to the second terminal portion.

[0152] The first and second terminal portions of the first electrode terminal are made of different materials, which facilitates welding one of the first and second terminal portions to the first electrode lead-out portion and the other of the first and second terminal portions to the busbar component. Furthermore, the first terminal portion is provided with a connecting portion, and the second terminal portion is provided with a hole portion. The connecting portion is at least partially disposed in the hole portion and fixedly connected to the second terminal portion, resulting in high connection strength between the first and second terminal portions, reducing the risk of separation between the first and second terminal portions, and improving the reliability of the battery cell.

[0153] The technical solutions described in the embodiments of this application are applicable to batteries and electrical devices that use batteries.

[0154] Electrical equipment can include vehicles, mobile phones, portable devices, laptops, ships, spacecraft, electric toys, and power tools, etc. Spacecraft include airplanes, rockets, space shuttles, and spacecraft, etc.; electric toys include stationary or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, etc.; power tools include metal cutting power tools, grinding power tools, assembly power tools, and railway power tools, which may include, but are not limited to, electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete vibrators, and electric planers, etc.

[0155] For ease of explanation, the following embodiments will use a vehicle 1000 as an example of electrical equipment.

[0156] Please refer to Figure 1, which is a structural schematic diagram of a vehicle 1000 provided in some embodiments of this application. The vehicle 1000 can be a gasoline-powered vehicle, a natural gas-powered vehicle, or a new energy vehicle. New energy vehicles can be pure electric vehicles, hybrid electric vehicles, or range-extended electric vehicles, etc. A battery 100 is disposed inside the vehicle 1000, and the battery 100 can be located at the bottom, front, or rear of the vehicle 1000. The battery 100 can be used to power the vehicle 1000; for example, the battery 100 can serve as the operating power source for the vehicle 1000. The vehicle 1000 may also include a controller 200 and a motor 300. The controller 200 is used to control the battery 100 to supply power to the motor 300, for example, to meet the power needs of the vehicle 1000 during startup, navigation, and driving.

[0157] In some embodiments of this application, the battery 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.

[0158] Please refer to Figure 2, which is an exploded view of a battery 100 provided in some embodiments of this application. The battery 100 includes a housing 10 and a battery cell 20, with the battery cell 20 housed within the housing 10. The housing 10 provides a space for the battery cell 20 and can have various structures. In some embodiments, the housing 10 may include a first portion 11 and a second portion 12, which overlap each other, jointly defining a space for accommodating the battery cell 20. The second portion 12 may be a hollow structure with one open end, and the first portion 11 may be a plate-like structure, covering the open side of the second portion 12 so that the first portion 11 and the second portion 12 jointly define the space. Alternatively, the first portion 11 and the second portion 12 may both be hollow structures with one open side, with the open side of the first portion 11 covering the open side of the second portion 12. Of course, the housing 10 formed by the first portion 11 and the second portion 12 can have various shapes, such as a cylinder, a cuboid, etc.

[0159] In battery 100, there can be multiple battery cells 20, which can be connected in series, parallel, or in a mixed manner. A mixed connection means that multiple battery cells 20 are connected in both series and parallel configurations. Multiple battery cells 20 can be directly connected in series, parallel, or in a mixed manner, and then the entire assembly of the multiple battery cells 20 is housed within the housing 10. Alternatively, battery 100 can also be composed of multiple battery cells 20 first connected in series, parallel, or in a mixed manner to form a battery module, and then multiple battery modules are connected in series, parallel, or in a mixed manner to form a whole, which is also housed within the housing 10. Battery 100 may also include other structures; for example, it may include a busbar component for electrical connection between the multiple battery cells 20.

[0160] Each battery cell 20 can be a secondary battery cell or a primary battery cell; it can also be a lithium-sulfur battery cell, a sodium-ion battery cell, or a magnesium-ion battery cell, but is not limited to these. The battery cell 20 can be cylindrical, flat, cuboid, or other shapes.

[0161] Please refer to Figures 3, 4, 5, 6, 7, and 8. Figure 3 is a structural schematic diagram of a battery cell 20 provided in some embodiments of this application. Figure 4 is an exploded view of a battery cell 20 provided in some embodiments of this application. Figure 5 is a structural schematic diagram of a wall portion 213 provided in some embodiments of this application. Figure 6 is a top view of a wall portion 213 provided in some embodiments of this application. Figure 7 is a cross-sectional view at position AA in Figure 6. Figure 8 is an enlarged view at position B in Figure 7. This application provides a battery cell 20, which includes a housing 21, an electrode assembly 24, and a first electrode terminal 22. The housing 21 has a wall portion 213, the electrode assembly 24 is disposed within the housing 21, and the first electrode terminal 22 is disposed on the wall portion 213. The first electrode terminal 22 includes a first terminal portion 221 and a second terminal portion 222. The first terminal portion 221 and the second terminal portion 222 are made of different materials, and the first terminal portion 221 and the second terminal portion 222 are stacked along the thickness direction of the wall portion 213. The first terminal portion 221 is provided with a connecting portion 223, and the second terminal portion 222 is provided with a hole portion 2222. The connecting portion 223 is at least partially provided in the hole portion 2222 and is fixedly connected to the second terminal portion 222.

[0162] Battery cell 20 refers to the smallest unit that makes up battery 100.

[0163] The housing 211 has an open-end receiving space for accommodating the electrode assembly 24. An end cap 212 is attached to the housing 211 and closes the opening.

[0164] 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 a 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 reliability. The material of end cap 212 can include, but is not limited to, copper, iron, aluminum, stainless steel, aluminum alloy, and plastic.

[0165] 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 24, 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, cylindrical, hexagonal prism, etc. Specifically, the shape of the housing 211 can be determined according to the specific shape and size of the electrode assembly 24. The material of the housing 211 can include, but is not limited to, copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc.

[0166] Electrode assembly 24 is the component in the battery cell 20 where electrochemical reactions occur. The casing 211 may contain one or more electrode assemblies 24. The electrode assembly 24 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 241 of the electrode assembly 24, while the portions of the positive and negative electrode sheets without active material each constitute a tab. The positive and negative tabs may be located together at one end of the main body or separately at both ends of the main body. During the charging and discharging process of the battery 100, the positive and negative active materials react with the electrolyte.

[0167] The wall portion 213 can be an end cap 212 of the outer casing 21, or it can be a wall of the housing 211 of the outer casing 21. Exemplarily, in Figures 3 and 4, the wall portion 213 is an end cap 212. In other embodiments, the wall portion 213 can be a side wall of the housing 211 adjacent to and connected to the end cap 212. In still other embodiments, the wall portion 213 can also be a bottom wall of the housing 211 opposite to the end cap 212.

[0168] The first electrode terminal 22 is used to electrically connect to the first electrode lead-out portion 242 of the electrode assembly 24 to input or output electrical energy from the battery cell 20. The first electrode lead-out portion 242 is a structure used to draw out electrical energy from the main body portion 241 or to introduce electrical energy into the main body portion 241. The first electrode lead-out portion 242 includes a first tab 2421, which is either a positive or negative tab as described above, and can be directly connected to the first electrode terminal 22. In other embodiments, the first electrode lead-out portion 242 may also include other electrical connection components connected to the first tab 2421. For example, the first electrode lead-out portion 242 may also include a first current collector 2422, which connects the first tab 2421 and the first electrode terminal 22 to guide the electrical energy of the electrode assembly 24 to the first electrode terminal 22 or receive the electrical energy introduced from the first electrode terminal 22.

[0169] The location of the first electrode terminal 22 can be used to determine which wall of the housing 21 is wall portion 213. For example, when the first electrode terminal 22 is located on the end cap 212, the end cap 212 is wall portion 213. When the first electrode terminal 22 is located on the bottom wall of the housing 211, the bottom wall is wall portion 213. When the first electrode terminal 22 is located on the side wall of the housing 211, the side wall is wall portion 213.

[0170] One of the first terminal portion 221 and the second terminal portion 222 is made of the same material as the first electrode lead-out portion 242 and is used for welding connection with the first electrode lead-out portion 242; the other of the first terminal portion 221 and the second terminal portion 222 is made of the same material as the busbar component and is used for welding connection with the busbar component.

[0171] Please refer to Figures 3, 4, 5, 6, 7, and 8. In the embodiment shown in the figures, the first terminal portion 221 is made of the same material as the first electrode lead-out portion 242 and is used for welding connection to the first electrode lead-out portion 242. The second terminal portion 222 is made of the same material as the busbar component and is used for welding connection to the busbar component.

[0172] "The first terminal portion 221 and the first electrode lead portion 242 are made of the same material" means that the main components of the first terminal portion 221 and the first electrode lead portion 242 are the same. Specifically, the main component of the first terminal portion 221 is a component comprising 50% or more of its composition, and similarly, the main component of the first electrode lead portion 242 is a component comprising 50% or more of its composition. The material of the first electrode lead portion 242 can also be various, such as copper or aluminum. If the first electrode lead portion 242 includes a positive electrode tab, then the material of the first electrode lead portion 242 is usually aluminum, and the main component of the first terminal portion 221 is also aluminum, with a content of 50% or more. If the first electrode lead portion 242 includes a negative electrode tab, then the material of the first electrode lead portion 242 is usually copper, and the main component of the first terminal portion 221 is also copper, with a content of 50% or more. In other words, the fact that the material of the first terminal portion 221 is the same as the material of the first electrode lead portion 242 means that the main components of the first terminal portion 221 and the first electrode lead portion 242 are the same. For example, if the first terminal portion 221 and the first electrode lead portion 242 are both made of a single material, such as copper or aluminum, then the materials of the first terminal portion 221 and the first electrode lead portion 242 are composed of the same metallic elements. If the first terminal portion 221 and the first electrode lead portion 242 are made of an alloy or mixed material, such as aluminum alloy or steel, then the difference in the materials of the first terminal portion 221 and the first electrode lead portion 242 means that the main components of the first terminal portion 221 and the first electrode lead portion 242 are different, that is, the components with a content of more than 50% in the alloy or mixed material are different.

[0173] "The second terminal portion 222 is made of the same material as the busbar component" means that the main components of the second terminal portion 222 and the busbar component are the same. Specifically, the main component of the second terminal portion 222 comprises 50% or more of its components, and similarly, the main component of the busbar component comprises 50% or more of its components. The busbar component can also be made of various materials, such as copper or aluminum. If the busbar component is made of aluminum, the main component of the second terminal portion 222 will also be aluminum, and its content will be 50% or more. In other words, the fact that the material of the second terminal 222 is the same as that of the bus component means that the main components of the second terminal 222 are the same as those of the bus component. For example, if the second terminal 222 and the bus component are both made of a single material, such as copper or aluminum, then the materials of the second terminal 222 and the bus component are composed of the same metallic elements. If the second terminal 222 and the bus component are made of an alloy or mixed material, such as aluminum alloy or steel, then the difference in the materials of the second terminal 222 and the bus component means that the main components of the second terminal 222 and the bus component are different, that is, the components with a content of more than 50% in the alloy or mixed material are different.

[0174] "The materials of the first terminal portion 221 and the second terminal portion 222 are different" means that the main components of the first terminal portion 221 and the second terminal portion 222 are different. The main component of the first terminal portion 221 is the component with a content of 50% or more in the components of the first terminal portion 221. Similarly, the main component of the second terminal portion 222 is the component with a content of 50% or more in the components of the second terminal portion 222. In other words, the difference in material between the first terminal portion 221 and the second terminal portion 222 means that the main components of the first terminal portion 221 and the second terminal portion 222 are different. For example, if both the first terminal portion 221 and the second terminal portion 222 are made of a single material, such as copper or aluminum, then the materials of the first terminal portion 221 and the second terminal portion 222 are composed of different metallic elements. If the first terminal portion 221 and the second terminal portion 222 are made of an alloy or mixed material, such as aluminum alloy or steel, then the difference in material between the first terminal portion 221 and the second terminal portion 222 means that the main components of the first terminal portion 221 and the second terminal portion 222 are different, that is, the components with a content of more than 50% in the alloy or mixed material are different. Optionally, the material of the first terminal portion 221 can be copper, and the material of the second terminal portion 222 can be aluminum.

[0175] Please refer to Figure 8. The thickness direction of the wall portion 213 is the X direction shown in the figure.

[0176] The first terminal portion 221 and the second terminal portion 222 are arranged along the thickness direction of the wall portion 213. Along the thickness direction of the wall portion 213, one of the first terminal portion 221 and the second terminal portion 222 is closer to the interior of the outer casing 21 than the other of the first terminal portion 221 and the second terminal portion 222. Referring to FIG8, in the embodiment shown in the figure, the first terminal portion 221 is closer to the interior of the outer casing 21 than the second terminal portion 222.

[0177] The connecting portion 223 is a component for fixed connection with the second terminal portion 222. The hole 2222 can be a through hole or a blind hole provided in the second terminal portion 222. The connecting portion 223 can be partially accommodated within the hole 2222, with another portion located outside the hole 2222; alternatively, the connecting portion 223 can be completely accommodated within the hole 2222. In some embodiments, the connecting portion 223 is riveted to the second terminal portion 222. In other embodiments, the connecting portion 223 is welded to the second terminal portion 222. In still other embodiments, the connecting portion 223 is bonded to the second terminal portion 222. The connecting portion 223 can be separately provided and connected to the first terminal portion 221, or it can be integrally formed with the first terminal portion 221.

[0178] The first terminal portion 221 and the second terminal portion 222 of the first electrode terminal 22 are made of different materials, which facilitates the welding of one of the first terminal portion 221 and the second terminal portion 222 to the first electrode lead-out portion 242, and the welding of the other of the first terminal portion 221 and the second terminal portion 222 to the busbar component. In addition, the first terminal portion 221 is provided with a connecting portion 223, and the second terminal portion 222 is provided with a hole portion 2222. The connecting portion 223 is at least partially provided in the hole portion 2222 and is fixedly connected to the second terminal portion 222, so that the first terminal portion 221 and the second terminal portion 222 have high connection strength, reduce the risk of separation of the first terminal portion 221 and the second terminal portion 222, and help improve the reliability of the battery cell 20.

[0179] Please refer to Figures 6, 7, 8, 9, and 10. Figure 9 is a structural schematic diagram of the first electrode terminal 22 provided in some embodiments of this application. Figure 10 is an exploded view of the first electrode terminal 22 provided in some embodiments of this application. In some embodiments, the connecting portion 223 includes a connecting body 2231 and a limiting body 2232. The connecting body 2231 is at least partially accommodated within the hole portion 2222. Along the thickness direction of the wall portion 213, the first terminal portion 221 and the limiting body 2232 are respectively connected to the two ends of the connecting body 2231. At least a portion of the second terminal portion 222 is clamped between the first terminal portion 221 and the limiting body 2232.

[0180] The limiting body 2232 is disposed opposite to the first terminal portion 221 along the thickness direction of the wall portion 213, and the connecting body 2231 extends along the thickness direction of the wall portion 213 and connects the limiting body 2232 and the first terminal portion 221.

[0181] Referring to Figures 6, 7, 8, 9 and 10, the first terminal portion 221 and the limiting body 2232 are respectively connected to both ends of the connecting body 2231 along the thickness direction of the wall portion 213. The first terminal portion 221 and the limiting body 2232 can cooperate to clamp at least a portion of the second terminal portion 222, thereby connecting the first terminal portion 221 and the second terminal portion 222 together.

[0182] The connector 2231 passes through the hole 2222. The first terminal 221 and the limiting body 2232 are respectively connected to the two ends of the connector 2231 and cooperate to clamp the second terminal 222, so that the connector 2231 cannot detach from the hole 2222 along the thickness direction of the wall 213. This allows the first terminal 221 and the second terminal 222 to be tightly connected, reducing the risk of separation of the first terminal 221 and the second terminal 222, and improving the reliability of the battery cell 20.

[0183] Referring to Figures 6, 7, 8, 9, and 10, in some embodiments, the hole 2222 includes a first hole segment 22221 and a second hole segment 22222 arranged along the thickness direction of the wall 213. The diameter of the second hole segment 22222 is larger than the diameter of the first hole segment 22221. The hole wall surfaces of the first hole segment 22221 and the second hole segment 22222 are connected by a stepped surface 22223. A connecting body 2231 passes through the first hole segment 22221, and a limiting body 2232 is at least partially located within the second hole segment 22222 and abuts against the stepped surface 22223.

[0184] Hole 2222 is a stepped hole. Hole 2222 includes a first hole segment 22221 and a second hole segment 22222, which are arranged along the thickness direction of wall 213. The first hole segment 22221 extends to the surface of the second terminal portion 222 facing the first terminal portion 221. The diameter of the first hole segment 22221 is smaller than the diameter of the second hole segment 22222, and the first hole segment 22221 is closer to the first terminal portion 221 than the second hole segment 22222. The stepped hole has a stepped surface 22223, which is a plane connecting the hole wall surfaces of the first hole segment 22221 and the second hole segment 22222.

[0185] The connector 2231 is partially or entirely accommodated in the first hole segment 22221, and the limiting body 2232 is partially or entirely accommodated in the second hole segment 22222. The limiting body 2232 abuts against the stepped surface 22223, thereby enabling the limiting body 2232 and the first terminal portion 221 to cooperate in clamping at least a portion of the second terminal portion 222.

[0186] The hole 2222 is a stepped hole. By at least partially placing the limiting body 2232 within the second hole segment 22222, the volume of the limiting body 2232 extending out of the second hole segment 22222 in the direction away from the connector 2231 can be reduced, thus reducing the space occupied inside the battery 100 and improving the energy density of the battery 100. Furthermore, since the volume of the limiting body 2232 extending out of the second hole segment 22222 in the direction away from the connector 2231 is small, it also facilitates welding the second terminal portion 222 to the busbar component.

[0187] Referring to Figures 6, 7, 8, 9 and 10, in some embodiments, along the thickness direction of the wall portion 213, the second terminal portion 222 has a first surface 2225 facing away from the first terminal portion 221, and the second hole segment 22222 extends to the first surface 2225.

[0188] The first hole segment 22221 extends to the surface of the second terminal portion 222 facing the first terminal portion 221, and the second hole segment 22222 extends to the first surface 2225 of the second terminal portion 222 away from the first terminal portion 221. The hole portion 2222 is a through hole that penetrates the second terminal portion 222 along the thickness direction of the wall portion 213.

[0189] When the second hole segment 22222 extends to the first surface 2225, the hole 2222 is a through hole that penetrates the second terminal portion 222 along the thickness direction of the wall portion 213. This makes it more convenient to fix the connecting portion 223 to the second terminal portion 222. For example, when the connecting portion 223 is riveted to the second terminal portion 222, the connecting portion 223 can be riveted by the second hole segment 22222.

[0190] Please refer to Figure 11, which is a cross-sectional view of the wall portion 213 provided in some other embodiments of this application. In some other embodiments, along the thickness direction of the wall portion 213, the second terminal portion 222 has a first surface 2225 facing away from the first terminal portion 221, and the second hole segment 22222 is at a distance from the first surface 2225.

[0191] There is a distance between the second hole segment 22222 and the first surface 2225, that is, the second hole segment 22222 does not penetrate the first surface 2225. At this time, the hole 2222 is a blind hole extending from the surface of the second terminal portion 222 facing the first terminal portion 221 toward the first surface 2225.

[0192] When there is a distance between the second hole segment 22222 and the first surface 2225, the hole 2222 is a blind hole provided in the second terminal portion 222. In this way, the area of ​​the first surface 2225 can be larger, thereby facilitating the welding of the second terminal portion 222 to the bus component or the first electrode lead-out portion 242.

[0193] Please refer to Figures 6, 7, 8, 9 and 10. In some embodiments, the limiting body 2232 is completely accommodated within the second hole segment 22222.

[0194] Along the thickness direction of the wall portion 213, the second terminal portion 222 has a first surface 2225 that is opposite to the first terminal portion 221. The limiting body 2232 has a second surface 22321 that is opposite to the first terminal portion 221. When the limiting body 2232 is fully accommodated in the second hole segment 22222, the first surface 2225 may be flush with the second surface 22321, or the second surface 22321 may be closer to the first terminal portion 221 than the first surface 2225.

[0195] When the limiting body 2232 is fully contained within the second hole segment 22222, the limiting body 2232 occupies less internal space in the battery 100, which is more conducive to improving the energy density of the battery 100 and facilitates the welding of the second terminal portion 222 to the busbar component or the first electrode lead-out portion 242.

[0196] Optionally, along the thickness direction of the wall portion 213, the second terminal portion 222 has a first surface 2225 that is opposite to the first terminal portion 221. The limiting body 2232 has a second surface 22321 that is opposite to the connector 2231, and the second surface 22321 is closer to the first terminal portion 221 than the first surface 2225.

[0197] By making the second surface 22321 closer to the first terminal portion 221 than the first surface 2225, the limiting body 2232 is less likely to interfere with the welding when welding the second terminal portion 222 and the bus component or the second terminal portion 222 and the first electrode lead-out portion 242, thereby making the welding of the second terminal portion 222 to the bus component or the first electrode lead-out portion 242 simpler and more convenient.

[0198] Referring to Figures 3, 4, 5, 6, 7, and 8, in some embodiments, along the thickness direction of the wall portion 213, the second terminal portion 222 has a first surface 2225 facing away from the first terminal portion 221, and the connecting portion 223 has a second surface 22321 facing away from the first terminal portion 221. The second surface 22321 is closer to the first terminal portion 221 than the first surface 2225.

[0199] By making the second surface 22321 closer to the first terminal portion 221 than the first surface 2225, the connecting portion 223 is less likely to interfere with the welding when welding the second terminal portion 222 and the bus component or the second terminal portion 222 and the first electrode lead-out portion 242, thereby making the welding of the second terminal portion 222 to the bus component or the first electrode lead-out portion 242 simpler and more convenient.

[0200] Referring to Figures 3, 4, 5, 6, 7, and 8, in some embodiments, along the thickness direction of the wall portion 213, the first terminal portion 221 has a third surface 22111 facing the second terminal portion 222, and the second terminal portion 222 has a fourth surface 2224 facing the first terminal portion 221. The third surface 22111 and the fourth surface 2224 are connected. A connecting portion 223 is provided on the third surface 22111. A hole 2222 penetrates the fourth surface 2224.

[0201] The third surface 22111 is the surface of the first terminal portion 221 facing the second terminal portion 222. The fourth surface 2224 is the surface of the second terminal portion 222 facing the first terminal portion 221. The third surface 22111 and the fourth surface 2224 are connected to form a connection interface.

[0202] The connection between the third surface 22111 and the fourth surface 2224 can be achieved by methods such as solid-liquid combination, solid-phase combination, hot rolling of laminated plates, diffusion pressing, overlay welding, and hot rolling of overlay welding.

[0203] One end of the hole 2222 extends to the fourth surface 2224, and the connecting part 223 protrudes from the third surface 22111. The connecting part 223 passes through the hole 2222 and is fixedly connected to the second terminal part 222.

[0204] The connection between the third surface 22111 and the fourth surface 2224 is beneficial to further improve the connection strength between the first terminal portion 221 and the second terminal portion 222. By providing the connecting portion 223 on the third surface 22111 and the hole portion 2222 penetrating the fourth surface 2224, the connection force between the connecting portion 223 and the second terminal portion 222 helps to keep the connection interface formed by the connection of the third surface 22111 and the fourth surface 2224 tightly connected, reducing the risk of loosening of the connection interface, which helps to reduce the internal resistance of the first electrode terminal 22 and improve the reliability of the battery cell 20.

[0205] Referring to Figures 6, 7, 8, 9, and 10, in some embodiments, the first terminal portion 221 is provided with a first groove 2211, and the second terminal portion 222 is at least partially accommodated within the first groove 2211. The bottom surface of the first groove 2211 is a third surface 22111.

[0206] Along the thickness direction of the wall portion 213, a first groove 2211 is provided on the side of the first terminal portion 221 facing the second terminal portion 222. Part or all of the second terminal portion 222 is accommodated in the first groove 2211.

[0207] The bottom surface of the first groove 2211 is the third surface 22111. The bottom surface of the first groove 2211 is connected to the fourth surface 2224 to form a connection interface. The connecting part 223 is disposed on the bottom surface of the first groove 2211.

[0208] By providing a first groove 2211 on the first terminal portion 221 and at least partially accommodating the second terminal portion 222 within the first groove 2211, the first groove 2211 serves a positioning function, thereby facilitating the connection between the first terminal portion 221 and the second terminal portion 222. Furthermore, the bottom surface of the first groove 2211 is a third surface 22111, making it more difficult for electrolyte to penetrate the connection interface formed by the third surface 22111 and the fourth surface 2224, further reducing the risk of metal corrosion caused by electrolyte penetration into the connection interface.

[0209] Please refer to Figure 12, which is a cross-sectional view of the wall portion 213 provided in some embodiments of this application. In some embodiments, the peripheral surface of the connecting portion 223 is connected to the wall surface of the hole portion 2222.

[0210] In some embodiments, the peripheral surface of the connecting portion 223 is welded to the wall surface of the hole portion 2222. In other embodiments, the peripheral surface of the connecting portion 223 is welded to the wall surface of the hole portion 2222.

[0211] When the peripheral surface of the connecting portion 223 is connected to the wall surface of the hole portion 2222, the connecting portion 223 and the second terminal portion 222 have a large connection surface, which is beneficial to make the first terminal portion 221 and the second terminal portion 222 have a high connection strength, reducing the risk of separation of the first terminal portion 221 and the second terminal portion 222, and improving the reliability of the battery cell 20.

[0212] In some embodiments, the first terminal portion 221 and the second terminal portion 222 are friction welded.

[0213] Friction welding is a method of welding that uses the heat generated by friction between the contact surfaces of workpieces as a heat source to cause plastic deformation of the workpieces under pressure.

[0214] Friction welding is used to connect the first terminal portion 221 and the second terminal portion 222. The welding quality is stable, and the connection strength of the first terminal portion 221 and the second terminal portion 222 after welding is high. This helps reduce the risk of separation between the first terminal portion 221 and the second terminal portion 222, and improves the reliability of the battery cell 20. By friction welding the first terminal portion 221 and the second terminal portion 222 on the basis of the fixed connection between the connecting portion 223 and the second terminal portion 222, the connection strength of the first terminal portion 221 and the second terminal portion 222 is further improved, further reducing the risk of separation between the first terminal portion 221 and the second terminal portion 222, and improving the reliability of the battery cell 20.

[0215] Referring to Figures 6, 7, 8, 9, and 10, in some embodiments, the distance between the axis of the connecting portion 223 and the axis of the second terminal portion 222 along the first direction is L. The minimum diameter of the second terminal portion 222 is D, satisfying: L / D≤0.1. The first direction is perpendicular to the thickness direction of the wall portion 213.

[0216] L represents the distance between the axis of the connecting portion 223 along the first direction and the axis of the second terminal portion 222. The first direction is perpendicular to the thickness direction of the wall portion 213. When the outer surface of the wall portion 213 is rectangular, the first direction can be the length direction or the width direction of the wall portion 213. When the outer surface of the wall portion 213 is circular, the first direction can be the radial direction of the wall portion 213. Referring to Figure 8, the first direction is the Y direction shown in the figure.

[0217] D represents the minimum diameter of the second terminal portion 222.

[0218] L / D represents the ratio of the distance between the axis of the connecting portion 223 along the first direction and the axis of the second terminal portion 222, and the minimum diameter of the second terminal portion 222.

[0219] The distance between the axis of the connecting portion 223 along the first direction and the axis of the second terminal portion 222, and the ratio of the minimum diameter of the second terminal portion 222, can be: L / D = 0.1, 0.09, 0.08, 0.07, 0.06, 0.05, 0.04, 0.03, 0.02, 0.01, 0, etc.

[0220] It should be noted that when L / D = 0, the axis of the connecting part 223 coincides with the axis of the second terminal part 222.

[0221] When L / D≤0.1, the axis of the connecting part 223 and the axis of the second terminal part 222 are basically coincident, which facilitates the combination of the first terminal part 221 and the second terminal part 222.

[0222] Optionally, the axis of the connecting portion 223 is friction-welded to the axis of the second terminal portion 222.

[0223] When the axis of the connecting part 223 coincides with the axis of the second terminal part 222, friction welding of the first terminal part 221 and the second terminal part 222 becomes simpler and more convenient, and the friction welding quality is higher.

[0224] Referring to Figures 6, 7, 8, 9 and 10, in some embodiments, along the thickness direction of the wall portion 213, the second terminal portion 222 is disposed on the side of the first terminal portion 221 away from the interior of the housing 21.

[0225] Along the thickness direction of the wall portion 213, the first terminal portion 221 and the second terminal portion 222 are stacked, and the first terminal portion 221 is closer to the interior of the outer casing 21 than the second terminal portion 222. In other words, along the thickness direction of the wall portion 213, the first terminal portion 221 is disposed on the side of the second terminal portion 222 facing the interior of the outer casing 21.

[0226] The first terminal portion 221 is closer to the interior of the outer casing 21 than the second terminal portion 222, which facilitates the welding of the first terminal portion 221 to the first electrode lead-out portion 242 and the welding of the second terminal portion 222 to the bus component.

[0227] In some embodiments, the battery cell 20 further includes a seal 27, which is at least partially disposed between the first terminal portion 221 and the wall portion 213.

[0228] The seal 27 is a structure capable of achieving a sealing effect, such as sealant, gasket, sheet, or ring. The seal 27 seals the first terminal portion 221 and the wall portion 213 to reduce the risk of electrolyte seeping into the composite interface.

[0229] The seal 27 seals the first terminal portion 221 and the wall portion 213, thereby reducing the risk of metal corrosion caused by electrolyte seeping between the first terminal portion 221 and the second terminal portion 222.

[0230] Referring to Figures 6, 7, 8, 9, and 10, in some embodiments, a first groove 2211 is provided on the side of the first terminal portion 221 facing away from the interior of the outer casing 21, and the second terminal portion 222 is at least partially accommodated within the first groove 2211. Along the thickness direction of the wall portion 213, the bottom surface of the first groove 2211 is a third surface 22111, and the second terminal portion 222 has a fourth surface 2224 facing the first terminal portion 221, with the third surface 22111 and the fourth surface 2224 connected. A sealing member 27 is disposed between the groove sidewall 22112 of the first groove 2211 and the wall portion 213.

[0231] Along the thickness direction of the wall portion 213, a first groove 2211 is provided on the side of the first terminal portion 221 away from the inside of the outer casing 21, and the second terminal portion 222 is partially or completely accommodated in the first groove 2211.

[0232] The bottom surface of the first groove 2211 and the fourth surface 2224 of the second terminal portion 222 facing the first terminal portion 221 are connected to form a connection interface.

[0233] The first groove 2211 also has a groove sidewall 22112, which is arranged around the groove bottom wall and protrudes from the groove bottom wall in a direction away from the interior of the outer casing 21.

[0234] The seal 27 is disposed between the groove sidewall 22112 and the wall portion 213 of the first groove 2211 to seal the first terminal portion 221 and the wall portion 213.

[0235] By providing a first groove 2211 on the first terminal portion 221 and at least partially accommodating the second terminal portion 222 within the first groove 2211, the first groove 2211 serves a positioning function, thereby facilitating the connection between the first terminal portion 221 and the second terminal portion 222. Furthermore, the sealing member 27 is disposed between the groove sidewall 22112 and the wall portion 213 of the first groove 2211, making it more difficult for electrolyte to penetrate into the connection interface formed by the connection of the third surface 22111 and the fourth surface 2224, further reducing the risk of metal corrosion caused by electrolyte penetration into the connection interface.

[0236] Referring to Figures 6, 7, 8, 9, and 10, in some embodiments, the wall portion 213 is provided with a lead-out hole 2131, and the seal 27 is at least partially located within the lead-out hole 2131. The battery cell 20 includes a first insulating member 25 disposed on the side of the wall portion 213 facing the interior of the outer casing 21, and the first insulating member 25 abuts against the seal 27. And / or the battery cell 20 includes a second insulating member 26, the second insulating member 26 being at least partially disposed between the first electrode terminal 22 and the wall portion 213, and the second insulating member 26 abuts against the seal 27.

[0237] The lead-out hole 2131 is a hole 2222 formed in the wall portion 213. The lead-out hole 2131 is used to set the first electrode terminal 22, which is connected to the electrode assembly 24 located inside the housing 21 and the busbar located outside the housing 21 through the lead-out hole 2131.

[0238] The first insulating member 25, commonly referred to as the lower plastic, is disposed along the thickness direction of the wall portion 213 on the side of the wall portion 213 facing the interior of the outer casing 21. The first insulating member 25 serves to insulate the electrical connection components within the casing 211 from the wall portion 213, thereby reducing the risk of short circuits. For example, the first insulating member 25 can be made of plastic, rubber, etc. The first insulating member 25 abuts against the side of the seal 27 facing the interior of the outer casing 21, thereby preventing the seal 27 from disengaging from the lead-out hole 2131 in the direction facing the interior of the outer casing 21.

[0239] The second insulating member 26 is commonly referred to as the upper plastic. The second insulating member 26 is partially or entirely disposed between the first electrode terminal 22 and the wall portion 213 to insulate and isolate the first electrode terminal 22 and the wall portion 213. For example, the second insulating member 26 can be plastic, rubber, etc. The second insulating member 26 abuts against the side of the seal 27 facing away from the interior of the housing 21 to prevent the seal 27 from disengaging from the lead-out hole 2131 in a direction facing away from the interior of the housing 21.

[0240] By providing the first insulating member 25, the first insulating member 25 can insulate and isolate the wall portion 213 and the electrode assembly 24, reducing the risk of short circuit due to contact between the wall portion 213 and the electrode assembly 24. The second insulating member 26 can insulate and isolate the first electrode terminal 22 and the wall portion 213, reducing the risk of short circuit due to contact between the first electrode terminal 22 and the wall portion 213. In addition, the first insulating member 25 and the second insulating member 26 respectively abut against both sides of the sealing member 27 along the thickness direction of the wall portion 213, which can limit the sealing member 27, keep the sealing member 27 within the lead-out hole 2131, and make the sealing member 27 stably seal the first terminal portion 221 and the wall portion 213, further reducing the risk of metal corrosion caused by electrolyte immersion in the composite interface of the first terminal portion 221 and the second terminal portion 222.

[0241] Referring to Figures 6, 7, 8, 9 and 10, in some embodiments, a portion of the first insulating member 25 is clamped between the first terminal portion 221 and the wall portion 213 along the thickness direction of the wall portion 213.

[0242] Along the thickness direction of the wall portion 213, a portion of the first insulating member 25 is located between the first terminal portion 221 and the wall portion 213, and abuts against the first terminal portion 221 and the wall portion 213. In other words, the first terminal portion 221 and the wall portion 213 cooperate to clamp a portion of the first wall portion 213 along the thickness direction of the wall portion 213.

[0243] By clamping a portion of the first insulating member 25 between the first terminal portion 221 and the wall portion 213, the first terminal portion 221 and the wall portion 213 cooperate to limit the first insulating member 25, so that the first insulating member 25 can stably abut against the sealing member 27, and the sealing member 27 stably seals the first terminal portion 221 and the wall portion 213.

[0244] Referring to Figures 6, 7, 8, 9, and 10, in some embodiments, a second groove 2132 is provided on the surface of the wall portion 213 facing the interior of the outer casing 21, and the lead-out hole 2131 communicates with the second groove 2132. The first insulating member 25 includes an insulating portion 251 accommodated within the second groove 2132, and the insulating portion 251 is clamped between the first terminal portion 221 and the wall portion 213.

[0245] The wall portion 213 has an inner surface facing the interior of the outer casing 21. A second groove 2132 is provided on the inner surface, and the second groove 2132 communicates with the outlet hole 2131.

[0246] The insulating portion 251 is the part of the first insulating member 25 that is accommodated within the second groove 2132. The first terminal portion 221 and the wall portion 213 cooperate to clamp the insulating portion 251. In other words, the portion of the first insulating member 25 that is clamped by the first terminal portion 221 and the wall portion 213 is accommodated within the second groove 2132.

[0247] By accommodating the insulating portion 251 within the second groove 2132 and clamping the insulating portion 251 with the first terminal portion 221 and the wall portion 213, the occupancy of the insulating portion 251 on the internal space of the battery cell 20 can be reduced, thereby improving the energy density of the battery cell 20.

[0248] Please refer to Figures 6, 7, 8, 9 and 10. In some embodiments, the second insulating member 26 is disposed around the second terminal portion 222, and the outer peripheral surface of the second terminal portion 222 is provided with a third groove 2221, in which the second insulating member 26 is partially accommodated.

[0249] The second insulating member 26 is disposed around the outside of the second terminal portion 222. A third groove 2221 is provided on the outer peripheral surface of the second terminal portion 222. The third groove 2221 may be an annular groove extending circumferentially along the second terminal portion 222.

[0250] In other embodiments, a plurality of third grooves 2221 are provided on the outer peripheral surface of the second terminal portion 222, and the plurality of third grooves 2221 are spaced apart along the circumferential direction of the second terminal portion 222.

[0251] The second insulating member 26 is partially accommodated within the third groove 2221 to be positioned and engaged with the third groove 2221.

[0252] By providing a third groove 2221 on the outer peripheral surface of the second terminal portion 222 and partially accommodating the second insulating member 26 within the third groove 2221, the second insulating member 26 can limit the second terminal portion 222 along the radial direction of the lead-out hole 2131.

[0253] Referring to Figures 6, 7, 8, 9, and 10, in some embodiments, the surface of the wall portion 213 facing away from the interior of the outer casing 21 is provided with a limiting protrusion 2133, and the second insulating member 26 is provided with a fourth groove 2223, in which the limiting protrusion 2133 is at least partially accommodated.

[0254] The wall portion 213 has an outer surface that faces away from the interior of the outer casing 21 along the thickness direction of the wall portion 213. The limiting protrusion 2133 is a protruding structure extending beyond the outer surface. In some embodiments, the limiting protrusion 2133 is an annular structure, surrounding the outer side of the outlet hole 2131. In other embodiments, the outer surface is provided with a plurality of limiting protrusions 2133, which are arranged circumferentially along the outlet hole 2131.

[0255] The second insulating member 26 is provided with a fourth groove 2223, which is used to cooperate with the limiting protrusion 2133 for limiting.

[0256] By providing a limiting protrusion 2133 on the surface of the wall portion 213 away from the interior of the outer shell 21, and by providing a fourth groove 2223 on the second insulating member 26 to cooperate with the limiting protrusion 2133, a better limiting effect can be achieved on the second insulating member 26.

[0257] In some embodiments, the second insulating member 26 is an injection molded part formed between the wall portion 213 and the first electrode terminal 22.

[0258] During manufacturing, the relative positions of the wall portion 213 and the first electrode terminal 22 can be fixed by a fixture, and then the second insulating member 26 can be injection molded between the wall portion 213 and the first electrode terminal 22.

[0259] By injection molding a second insulating member 26 between the wall portion 213 and the first electrode terminal 22, the second insulating member 26 can limit the first electrode terminal 22 and enhance the connection strength between the first electrode terminal 22 and the wall portion 213.

[0260] Please refer to Figures 6, 7, 8, 9 and 10. In some embodiments, the wall portion 213 is provided with a lead-out hole 2131, and the first terminal portion 221 and / or the second terminal portion 222 are at least partially accommodated in the lead-out hole 2131.

[0261] "The first terminal portion 221 and / or the second terminal portion 222 are at least partially accommodated within the lead-out hole 2131" can mean that the first terminal portion 221 is at least partially accommodated within the lead-out hole 2131 and the second terminal portion 222 is at least partially accommodated within the lead-out hole 2131, or the first terminal portion 221 is at least partially accommodated within the lead-out hole 2131 and the second terminal portion 222 is located outside the lead-out hole 2131, or the second terminal portion 222 is at least partially accommodated within the lead-out hole 2131 and the first terminal portion 221 is located outside the lead-out hole 2131.

[0262] By at least partially accommodating the first terminal portion 221 and / or the second terminal portion 222 within the lead-out hole 2131, the occupation of the first terminal portion 221 and / or the second terminal portion 222 on the internal space of the battery cell 20 or the internal space of the battery 100 can be reduced, which is beneficial to improving the energy density of the battery cell 20 or the battery 100.

[0263] Optionally, a portion of the first terminal portion 221 is accommodated within the lead-out hole 2131, and another portion of the first terminal portion 221 protrudes from the surface of the wall portion 213 facing the interior of the housing 21 in a direction facing the interior of the housing 21. And / or a portion of the second terminal portion 222 is accommodated within the lead-out hole 2131, and another portion of the second terminal portion 222 protrudes from the surface of the wall portion 213 facing away from the interior of the housing 21 in a direction away from the interior of the housing 21.

[0264] Along the thickness direction of the wall portion 213, a portion of the first terminal portion 221 is located inside the lead-out hole 2131, and another portion of the first terminal portion 221 extends out of the lead-out hole 2131 in the direction facing the inside of the outer casing 21.

[0265] Along the thickness direction of the wall portion 213, a portion of the second terminal portion 222 is located inside the lead-out hole 2131, and another portion of the second terminal portion 222 extends out of the lead-out hole 2131 in a direction away from the interior of the outer casing 21.

[0266] A portion of the first terminal portion 221 is housed within the lead-out hole 2131, reducing its footprint within the internal space of the battery cell 20 and increasing the energy density of the battery cell 20. Another portion of the first terminal portion 221 protrudes from the surface of the wall portion 213 facing the interior of the outer casing 21, facilitating welding of the first terminal portion 221 to the first electrode lead-out portion 242. A portion of the second terminal portion 222 is housed within the lead-out hole 2131, reducing its footprint within the internal space of the battery 100 and increasing the energy density of the battery 100. Another portion of the second terminal portion 222 protrudes from the surface of the wall portion 213 away from the interior of the outer casing 21, facilitating welding of the second terminal portion 222 to the busbar component.

[0267] In some embodiments, the battery cell 20 further includes a second electrode terminal 23, which is insulated and mounted on the wall portion 213. The electrode assembly 24 also has a second electrode lead-out portion 243, and the second electrode terminal 23 is electrically connected to the second electrode lead-out portion 243.

[0268] The second electrode lead-out portion 243 is a structure used to lead out electrical energy from the main body portion 241 or to introduce electrical energy into the main body portion 241. The second electrode lead-out portion 243 includes a second tab 2431, which may include the aforementioned positive or negative tab, and can be directly connected to the second electrode terminal 23. In some embodiments, the second electrode lead-out portion 243 may also include other electrical connection components connected to the second tab 2431. For example, the second electrode lead-out portion 243 may also include a second current collector 2432, which connects the second tab 2431 and the second electrode terminal 23 to guide the electrical energy of the electrode assembly 24 to the second electrode terminal 23 or receive the electrical energy introduced from the second electrode terminal 23.

[0269] The first electrode 2421 and the second electrode 2431 have opposite polarities. For example, when the first electrode 2421 is the negative electrode, the second electrode 2431 is the positive electrode. Similarly, the first electrode terminal 22 and the second electrode terminal 23 have opposite polarities. For example, when the first electrode terminal 22 is the negative electrode terminal, the second electrode terminal 23 is the positive electrode terminal.

[0270] The second electrode terminal 23 is insulated from and mounted on the wall portion 213, meaning that the second electrode terminal 23 is insulated from and isolated from the wall portion 213. Optionally, the battery cell 20 includes a third insulating member disposed between the second electrode terminal 23 and the wall portion 213 to insulate and isolate the second electrode terminal 23 from the wall portion 213.

[0271] The structure of the second electrode terminal 23 can be the same as that of the first electrode terminal 22, or it can be different from the structure of the first electrode terminal 22.

[0272] Optionally, the first electrode terminal 22 is the negative electrode terminal, and the second electrode terminal 23 is the positive electrode terminal. The second electrode terminal 23 is made of aluminum.

[0273] Please refer to Figures 13 and 14. Figure 13 is a schematic block diagram of a battery cell 20 manufacturing method provided in some embodiments of this application. Figure 14 is a schematic block diagram of a battery cell 20 manufacturing method provided in other embodiments of this application. This application also provides a battery cell 20 manufacturing method, which includes:

[0274] Step S100: Manufacture the first electrode terminal 22;

[0275] Step S200: Provide housing 21, housing 21 having wall portion 213;

[0276] Step S300: Install the first electrode terminal 22 onto the wall portion 213;

[0277] Step S100 includes:

[0278] Step S110: Provide a first terminal portion 221 and a second terminal portion 222, wherein the first terminal portion 221 is provided with a connecting portion 223 and the second terminal portion 222 is provided with a hole portion 2222;

[0279] Step S120: Insert the connecting part 223 into the hole 2222;

[0280] Step S130: Fix the connecting part 223 to the second terminal part 222.

[0281] Please refer to Figure 15, which is a schematic block diagram of a battery cell 20 manufacturing method provided in some embodiments of this application. In some embodiments, after step S120, the battery cell 20 manufacturing method further includes:

[0282] Step S121: Connect the first terminal portion 221 and the second terminal portion 222.

[0283] The connection between the first terminal part 221 and the second terminal part 222 can be achieved by methods such as solid-liquid combination, solid-phase combination, hot rolling of laminated plates, diffusion pressing, overlay welding, and hot rolling of overlay welding.

[0284] Based on the fixed connection between the connecting part 223 and the second terminal part 222, the first terminal part 221 and the second terminal part 222 are then connected, which helps to further improve the connection strength between the first terminal part 221 and the second terminal part 222, further reduce the risk of separation between the first terminal part 221 and the second terminal part 222, and help to improve the reliability of the battery cell 20.

[0285] Please refer to Figure 16, which is a schematic block diagram of a method for manufacturing a battery cell 20 according to some embodiments of this application. In some embodiments, step S121 includes:

[0286] Step S1211: Friction weld the first terminal portion 221 and the second terminal portion 222.

[0287] The first terminal portion 221 and the second terminal portion 222 are connected by friction welding. The welding quality is stable and the connection strength of the first terminal portion 221 and the second terminal portion 222 after welding is high. This helps to reduce the risk of separation of the first terminal portion 221 and the second terminal portion 222 and improves the reliability of the battery cell 20.

[0288] Please refer to Figures 17, 18, and 19. Figure 17 is a schematic block diagram of a battery cell 20 manufacturing method provided in some embodiments of this application. Figure 18 is a cross-sectional view of the connecting portion 223 and the second terminal portion 222 before riveting provided in some embodiments of this application. Figure 19 is a cross-sectional view of the connecting portion 223 and the second terminal portion 222 after riveting provided in some embodiments of this application. In some embodiments, step S130 includes:

[0289] Step S131: Rivet the connecting part 223 to the second terminal part 222.

[0290] Please refer to Figure 18. Before the riveted connection part 223, the connection part 223 is a columnar structure, and the connection part 223 passes through the hole part 2222.

[0291] Referring to Figure 19, after riveting the connecting portion 223, the connecting portion 223 includes a connecting body 2231 and a limiting body 2232, with the connecting body 2231 at least partially accommodated within the hole portion 2222. Along the thickness direction of the wall portion 213, the first terminal portion 221 and the limiting body 2232 are respectively connected to both ends of the connecting body 2231, and at least a portion of the second terminal portion 222 is clamped between the first terminal portion 221 and the limiting body 2232.

[0292] By riveting the connecting part 223 to the second terminal part 222, the connecting part 223 and the second terminal part 222 are fixed, so that the first terminal part 221 and the second terminal part 222 have high connection strength, reducing the risk of separation of the first terminal part 221 and the second terminal part 222, which is beneficial to improving the reliability of the battery cell 20.

[0293] Please refer to Figures 20, 21, and 22. Figure 20 is a schematic block diagram of a battery cell 20 manufacturing method provided in some embodiments of this application. Figure 21 is a cross-sectional view of the first terminal portion 221 and the second terminal portion 222 before friction welding provided in some embodiments of this application. Figure 22 is a cross-sectional view of the first terminal portion 221 and the second terminal portion 222 after friction welding provided in some embodiments of this application. In some embodiments, the connecting portion 223 includes a connecting body 2231 and a limiting body 2232, and the first terminal portion 221 and the limiting body 2232 are respectively connected to the two ends of the connecting body 2231. Step S130 includes:

[0294] Step S132: Friction weld the first terminal portion 221 and the second terminal portion 222, so that a portion of the second terminal portion 222 is extruded between the first terminal portion 221 and the limiting body 2232, so that a portion of the second terminal portion 222 is clamped between the first terminal portion 221 and the limiting body 2232.

[0295] Referring to Figure 21, before friction welding the first terminal portion 221 and the second terminal portion 222, the connecting portion 223 is first inserted into the hole portion 2222. At this time, the connecting portion 223 includes a connecting body 2231 and a limiting body 2232, with the connecting body 2231 at least partially accommodated within the hole portion 2222. Along the thickness direction of the wall portion 213, the first terminal portion 221 and the limiting body 2232 are respectively connected to both ends of the connecting body 2231. To facilitate the insertion of the connecting portion 223, the minimum diameter of the hole portion 2222 is greater than the maximum diameter of the connecting portion 223. In embodiments where the hole portion 2222 includes a first hole segment 22221 and a second hole segment 22222, the diameter of the first hole segment 22221 is greater than the diameter of the limiting body 2232.

[0296] Referring to Figure 22, during friction welding of the first terminal portion 221 and the second terminal portion 222, a portion of the second terminal portion 222 is squeezed between the first terminal portion 221 and the limiting body 2232, causing the diameter of the first hole segment 22221 to gradually decrease. Eventually, the diameter of the first hole segment 22221 is smaller than the diameter of the limiting body 2232, so that a portion of the second terminal portion 222 is clamped between the first terminal portion 221 and the limiting body 2232.

[0297] The connecting portion 223 is prefabricated to have a connecting body 2231 and a limiting body 2232, and the connecting portion 223 is accommodated in the hole portion 2222. During the friction welding of the first terminal portion 221 and the second terminal portion 222, a portion of the second terminal portion 222 is squeezed between the first terminal portion 221 and the limiting body 2232, thereby enabling the second terminal portion 222 to be clamped between the first terminal portion 221 and the limiting body 2232. This achieves both a fixed connection between the connecting portion 223 and the second terminal portion 222 and friction welding between the first terminal portion 221 and the second terminal portion 222. This results in a high connection strength between the first terminal portion 221 and the second terminal portion 222, reduces the risk of separation between the first terminal portion 221 and the second terminal portion 222, and helps improve the reliability of the battery cell 20.

[0298] Please refer to Figures 23 and 24. Figure 23 is a schematic block diagram of a method for manufacturing a battery cell 20 according to some other embodiments of this application. Figure 24 is a cross-sectional view of a first electrode terminal 22 according to some other embodiments of this application. In some other embodiments, step S130 includes:

[0299] Step S133: Connect the peripheral surface of the connecting part 223 to the wall surface of the hole 2222.

[0300] In some embodiments, the peripheral surface of the connecting portion 223 is welded to the wall surface of the hole portion 2222.

[0301] In other embodiments, the peripheral surface of the connecting portion 223 is welded and bonded to the wall surface of the hole portion 2222.

[0302] When the peripheral surface of the connecting portion 223 is connected to the wall surface of the hole portion 2222, the connecting portion 223 and the second terminal portion 222 have a large connection surface, which is beneficial to make the first terminal portion 221 and the second terminal portion 222 have a high connection strength, reducing the risk of separation of the first terminal portion 221 and the second terminal portion 222, and improving the reliability of the battery cell 20.

[0303] Please refer to Figure 25, which is a schematic block diagram of a method for manufacturing a battery cell 20 according to some other embodiments of this application. In some other embodiments, the wall portion 213 is provided with an outlet hole 2131.

[0304] Step S300 includes:

[0305] Step S310: A sealing element 27 is fitted onto the outer side of the first terminal portion 221;

[0306] Step S320: A first insulating element 25 is provided on the side of the wall portion 213 facing the interior of the outer casing 21;

[0307] Step S330: Insert the first electrode terminal 22 into the lead-out hole 2131, and press the first terminal portion 221 against the wall portion 213;

[0308] Step S340: The second insulating member 26 is injection molded between the second terminal portion 222 and the wall portion 213, so that the first insulating member 25 and the second insulating member 26 respectively abut against the two sides of the sealing member 27.

[0309] By providing the first insulating member 25, the first insulating member 25 can insulate and isolate the wall portion 213 and the electrode assembly 24, reducing the risk of short circuit due to contact between the wall portion 213 and the electrode assembly 24. The second insulating member 26 can insulate and isolate the first electrode terminal 22 and the wall portion 213, reducing the risk of short circuit due to contact between the first electrode terminal 22 and the wall portion 213. In addition, the first insulating member 25 and the second insulating member 26 respectively abut against both sides of the sealing member 27 along the thickness direction of the wall portion 213, which can limit the sealing member 27, keep the sealing member 27 within the lead-out hole 2131, and make the sealing member 27 stably seal the first terminal portion 221 and the wall portion 213, further reducing the risk of metal corrosion caused by electrolyte immersion in the composite interface of the first terminal portion 221 and the second terminal portion 222.

[0310] This application embodiment also provides a battery 100, which includes the battery cell 20 described above.

[0311] 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.

[0312] Please refer to Figures 3 to 10 for some embodiments of this application.

[0313] This application provides a battery cell 20, which includes a housing 21 and a first electrode terminal 22. The housing 21 has a wall portion 213, and the first electrode terminal 22 is disposed on the wall portion 213. The first electrode terminal 22 includes a first terminal portion 221 and a second terminal portion 222, which are made of different materials and are composite with each other. The first terminal portion 221 is provided with a connecting portion 223, which is riveted to the second terminal portion 222. The first terminal portion 221 and the second terminal portion 222 are made of different materials and are composite with each other, thereby facilitating the welding of one of the first terminal portion 221 and the second terminal portion 222 to a first electrode lead-out portion 242, and the welding of the other of the first terminal portion 221 and the second terminal portion 222 to a busbar component. In addition, the first terminal portion 221 is also provided with a connecting portion 223, which is riveted to the second terminal portion 222, further increasing the connection strength between the first terminal portion 221 and the second terminal portion 222, reducing the risk of separation between the first terminal portion 221 and the second terminal portion 222, and helping to improve the reliability of the battery cell 20.

[0314] The first terminal portion 221 has a third surface 22111 facing the second terminal portion 222, and the second terminal portion 222 has a fourth surface 2224 facing the first terminal portion 221. The third surface 22111 and the fourth surface 2224 are composite together. A connecting portion 223 is disposed on the third surface 22111, and the second terminal portion 222 has a hole 2222 that penetrates the fourth surface 2224. The connecting portion 223 is at least partially accommodated within the hole 2222. By disposing the connecting portion 223 on the third surface 22111 and at least partially accommodating it within the hole 2222, the connecting portion 223 and the second terminal portion 222 are riveted together. The external force provided by the riveting helps to maintain a tight connection between the composite interface formed by the third surface 22111 and the fourth surface 2224, reducing the risk of loosening of the composite interface, which in turn helps to reduce the internal resistance of the first electrode terminal 22 and improve the reliability of the battery cell 20.

[0315] Along the thickness direction of the wall portion 213, the first terminal portion 221 and the second terminal portion 222 are stacked; the third surface 22111 faces the second terminal portion 222 along the thickness direction of the wall portion 213, and the fourth surface 2224 faces the first terminal portion 221 along the thickness direction of the wall portion 213. By stacking the first terminal portion 221 and the second terminal portion 222 along the thickness direction of the wall portion 213, it is not only convenient for the one of the first terminal portion 221 and the second terminal portion 222 facing the first electrode lead-out portion 242 to be welded to the first electrode lead-out portion 242, and for the one of the first terminal portion 221 and the second terminal portion 222 facing away from the first electrode lead-out portion 242 to be welded to the busbar component, but it is also beneficial to have a larger welding area, improve the welding strength, and obtain a larger flow area. In addition, the third surface 22111 faces the second terminal portion 222 along the thickness direction of the wall portion 213, and the fourth surface 2224 faces the first terminal portion 221 along the thickness direction of the wall portion 213. The composite interface formed by the third surface 22111 and the fourth surface 2224 is approximately perpendicular to the thickness direction of the wall portion 213, so that the electrolyte needs to completely submerge the first terminal portion 221 and the second terminal portion 222 that is closer to the inside of the outer casing 21 before it can enter the composite interface. This reduces the risk of metal corrosion caused by the electrolyte penetrating the composite interface.

[0316] The first terminal portion 221 is provided with a first groove 2211, and the second terminal portion 222 is at least partially accommodated within the first groove 2211. The bottom surface of the first groove 2211 is a third surface 22111. By providing the first groove 2211 on the first terminal portion 221 and accommodating the second terminal portion 222 at least partially within the first groove 2211, the first groove 2211 can serve a positioning function, thereby facilitating the bonding of the first terminal portion 221 and the second terminal portion 222. In addition, the bottom surface of the first groove 2211 being a third surface 22111 makes it more difficult for the electrolyte to penetrate into the bonding interface, further reducing the risk of metal corrosion caused by the electrolyte penetrating into the bonding interface.

[0317] Along the thickness direction of the wall portion 213, the second terminal portion 222 is composited to the side of the first terminal portion 221 facing away from the interior of the housing 21. The battery cell 20 also includes a seal 27, which is configured to seal the first terminal portion 221 and the wall portion 213. The first terminal portion 221 is closer to the interior of the housing 21 than the second terminal portion 222, facilitating welding of the first terminal portion 221 to the first electrode lead-out portion 242 and welding of the second terminal portion 222 to the busbar component. The seal 27 seals the first terminal portion 221 and the wall portion 213, reducing the risk of electrolyte infiltration into the composite interface of the first terminal portion 221 and the second terminal portion 222, which could lead to metal corrosion.

[0318] A first groove 2211 is provided on the side of the first terminal portion 221 facing away from the interior of the outer casing 21, and the second terminal portion 222 is at least partially accommodated within the first groove 2211. Along the thickness direction of the wall portion 213, the bottom surface of the first groove 2211 is a third surface 22111, and the second terminal portion 222 has a fourth surface 2224 facing the first terminal portion 221. The third surface 22111 and the fourth surface 2224 are combined with each other. A sealing member 27 is disposed between the groove sidewall 22112 of the first groove 2211 and the wall portion 213. By providing the first groove 2211 on the first terminal portion 221 and allowing the second terminal portion 222 to be at least partially accommodated within the first groove 2211, the first groove 2211 can serve a positioning function, thereby facilitating the combination of the first terminal portion 221 and the second terminal portion 222. In addition, the seal 27 is disposed between the groove sidewall 22112 and the wall portion 213 of the first groove 2211, making it more difficult for the electrolyte to penetrate into the composite interface, further reducing the risk of metal corrosion caused by the electrolyte penetrating into the composite interface.

[0319] The wall portion 213 is provided with a lead-out hole 2131, and the seal 27 is at least partially located within the lead-out hole 2131. The battery cell 20 includes a first insulating member 25, which is disposed on the side of the wall portion 213 facing the interior of the housing 21. The first insulating member 25 abuts against the seal 27 to prevent the seal 27 from disengaging from the lead-out hole 2131 in the direction facing the interior of the housing 21. And / or the battery cell 20 includes a second insulating member 26, which is at least partially disposed between the first electrode terminal 22 and the wall portion 213 to insulate the first electrode terminal 22 and the wall portion 213. The second insulating member 26 abuts against the seal 27 to prevent the seal 27 from disengaging from the lead-out hole 2131 in the direction away from the interior of the housing 21. By providing the first insulating member 25, the first insulating member 25 can insulate the wall portion 213 and the electrode assembly 24, reducing the risk of short circuit due to contact between the wall portion 213 and the electrode assembly 24. The second insulating member 26 can insulate and isolate the first electrode terminal 22 and the wall portion 213, reducing the risk of short circuit due to contact between the first electrode terminal 22 and the wall portion 213. In addition, the first insulating member 25 and the second insulating member 26 respectively abut against the two sides of the sealing member 27 along the thickness direction of the wall portion 213, which can limit the sealing member 27, keep the sealing member 27 in the lead-out hole 2131, and make the sealing member 27 stably seal the first terminal portion 221 and the wall portion 213, further reducing the risk of metal corrosion caused by electrolyte infiltration into the composite interface of the first terminal portion 221 and the second terminal portion 222.

[0320] 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

A type of battery cell, wherein, include: The outer shell has walls; Electrode assembly, disposed within the housing; A first electrode terminal is disposed on the wall portion. The first electrode terminal includes a first terminal portion and a second terminal portion. The first terminal portion and the second terminal portion are made of different materials. The first terminal portion and the second terminal portion are stacked along the thickness direction of the wall portion. The first terminal portion is provided with a connecting portion, and the second terminal portion is provided with a hole portion. The connecting portion is at least partially disposed in the hole portion and is fixedly connected to the second terminal portion. According to claim 1, the battery cell, wherein, The connecting portion includes a connecting body and a limiting body. The connecting body is at least partially accommodated within the hole. Along the thickness direction of the wall portion, the first terminal portion and the limiting body are respectively connected to both ends of the connecting body. At least a portion of the second terminal portion is clamped between the first terminal portion and the limiting body. According to claim 2, the battery cell, wherein, The hole includes a first hole segment and a second hole segment arranged along the thickness direction of the wall. The diameter of the second hole segment is larger than that of the first hole segment. The hole wall surfaces of the first hole segment and the second hole segment are connected by a stepped surface. The connector passes through the first hole segment, and the limiting body is at least partially located in the second hole segment and abuts against the stepped surface. According to claim 3, the battery cell, wherein, Along the thickness direction of the wall portion, the second terminal portion has a first surface opposite to the first terminal portion, and the second hole segment extends to the first surface. According to claim 3, the battery cell, wherein, Along the thickness direction of the wall portion, the second terminal portion has a first surface that is opposite to the first terminal portion, and the second hole segment is at a distance from the first surface. The battery cell according to any one of claims 3-5, wherein, The limiting body is completely contained within the second hole segment. According to the battery cell of claim 6, wherein, Along the thickness direction of the wall portion, the second terminal portion has a first surface opposite to the first terminal portion, and the limiting body has a second surface opposite to the connecting body, the second surface being closer to the first terminal portion than the first surface. The battery cell according to any one of claims 1-7, wherein, Along the thickness direction of the wall portion, the second terminal portion has a first surface facing away from the first terminal portion, and the connecting portion has a second surface facing away from the first terminal portion, the second surface being closer to the first terminal portion than the first surface. The battery cell according to any one of claims 1-8, wherein, Along the thickness direction of the wall portion, the first terminal portion has a third surface facing the second terminal portion, the second terminal portion has a fourth surface facing the first terminal portion, the third surface and the fourth surface are connected; the connecting portion is disposed on the third surface, and the hole portion penetrates the fourth surface. According to claim 9, the battery cell, wherein, The first terminal portion is provided with a first groove, and the second terminal portion is at least partially accommodated in the first groove, wherein the bottom surface of the first groove is the third surface. The battery cell according to any one of claims 1-10, wherein, The peripheral surface of the connecting part is connected to the hole wall surface of the hole. The battery cell according to any one of claims 1-11, wherein, The first terminal portion and the second terminal portion are friction welded. According to claim 12, the battery cell, wherein, Along the first direction, the distance between the axis of the connecting portion and the axis of the second terminal portion is L, and the minimum diameter of the second terminal portion is D, satisfying: L / D≤0.1; the first direction is perpendicular to the thickness direction of the wall portion. According to claim 13, the battery cell, wherein, The axis of the connecting part coincides with the axis of the second terminal part. The battery cell according to any one of claims 1-14, wherein, Along the thickness direction of the wall portion, the second terminal portion is disposed on the side of the first terminal portion away from the interior of the housing. According to the battery cell of claim 15, wherein, The battery cell also includes a seal, which is at least partially disposed between the first terminal portion and the wall portion. According to the battery cell of claim 16, wherein, The first terminal portion has a first groove on the side facing away from the interior of the housing, and the second terminal portion is at least partially accommodated in the first groove; along the thickness direction of the wall portion, the bottom surface of the first groove is a third surface, and the second terminal portion has a fourth surface facing the first terminal portion, the third surface and the fourth surface are connected; the seal is at least partially disposed between the groove sidewall of the first groove and the wall portion. The battery cell according to claim 16 or 17, wherein, The wall portion is provided with an outlet hole, and the seal is at least partially located within the outlet hole; the battery cell includes a first insulating member, which is disposed on the side of the wall portion facing the interior of the housing, and the first insulating member abuts against the seal; and / or the battery cell includes a second insulating member, which is at least partially disposed between the first electrode terminal and the wall portion, and the second insulating member abuts against the seal. According to the battery cell of claim 18, wherein, Along the thickness direction of the wall portion, a portion of the first insulating member is clamped between the first terminal portion and the wall portion. According to claim 19, the battery cell, wherein, The wall portion has a second groove on its surface facing the inside of the housing, the lead-out hole communicates with the second groove, and the first insulating member includes an insulating portion accommodated in the second groove, the insulating portion being clamped between the first terminal portion and the wall portion. The battery cell according to any one of claims 18-20, wherein, The second insulating member is disposed around the second terminal portion, and a third groove is provided on the outer peripheral surface of the second terminal portion, and the second insulating member is partially accommodated in the third groove. The battery cell according to any one of claims 18-21, wherein, The surface of the wall portion facing away from the interior of the outer shell is provided with a limiting protrusion, and the second insulating member is provided with a fourth groove, wherein the limiting protrusion is at least partially accommodated within the fourth groove. The battery cell according to any one of claims 18-22, wherein, The second insulating component is an injection molded component formed between the wall portion and the first electrode terminal. The battery cell according to any one of claims 1-23, wherein, The wall portion is provided with an outlet hole, and the first terminal portion and / or the second terminal portion are at least partially accommodated within the outlet hole. According to claim 24, the battery cell, wherein, A portion of the first terminal portion is accommodated within the lead-out hole, and another portion of the first terminal portion protrudes from the surface of the wall portion facing the interior of the housing in a direction toward the interior of the housing; and / or a portion of the second terminal portion is accommodated within the lead-out hole, and another portion of the second terminal portion protrudes from the surface of the wall portion away from the interior of the housing in a direction away from the interior of the housing. A method for manufacturing a single battery cell, wherein, include: Step S100: Manufacturing the first electrode terminal; Step S2 00: Provide a housing having a wall portion; Step S3 00: Install the first electrode terminal onto the wall portion; Step S100 includes: Step S110: providing a first terminal portion and a second terminal portion, wherein the first terminal portion is provided with a connecting portion and the second terminal portion is provided with a hole portion; Step S120: inserting the connecting portion into the hole portion; Step S130: fixing the connecting portion to the second terminal portion. According to the battery cell manufacturing method of claim 26, wherein, After step S120, the battery cell manufacturing method further includes: step S121: connecting the first terminal portion and the second terminal portion. According to the battery cell manufacturing method of claim 27, wherein, Step S121 includes: Step S1211: Friction welding the first terminal portion and the second terminal portion. The method for manufacturing a battery cell according to any one of claims 26-28, wherein, Step S130 includes: Step S131: riveting the connecting part to the second terminal part. The method for manufacturing a battery cell according to any one of claims 26-28, wherein, The connecting part includes a connecting body and a limiting body. The first terminal part and the limiting body are respectively connected to the two ends of the connecting body. Step S130 includes: Step S132: Friction welding the first terminal part and the second terminal part, so that a portion of the second terminal part is squeezed between the first terminal part and the limiting body, so that a portion of the second terminal part is clamped between the first terminal part and the limiting body. The method for manufacturing a battery cell according to any one of claims 26-28, wherein, Step S130 includes: Step S133: Connecting the peripheral surface of the connecting part to the wall surface of the hole. The method for manufacturing a battery cell according to any one of claims 26-31, wherein, The wall portion is provided with an outlet hole; step S300 includes: step S310: a sealing member is sleeved on the outside of the first terminal portion; step S320: a first insulating member is provided on the side of the wall portion facing the inside of the outer shell; step S330: the first electrode terminal is inserted into the outlet hole, and the first terminal portion presses part of the first insulating member against the wall portion; step S340: a second insulating member is injection molded between the second terminal portion and the wall portion, such that the first insulating member and the second insulating member respectively abut against both sides of the sealing member. A type of battery, wherein, Includes the battery cell according to any one of claims 1-25. An electrical appliance, wherein, Includes a battery cell according to any one of claims 1-25, the battery cell being used to provide electrical energy to the electrical equipment.

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