WO2024020877A1

WO2024020877A1 - Battery cell, battery and electrical apparatus

Info

Publication number: WO2024020877A1
Application number: PCT/CN2022/108324
Authority: WO
Inventors: 李全国; 叶永煌; 刘倩; 陈佳华; 孙婧轩; 喻春鹏; 肖得隽
Original assignee: 宁德时代新能源科技股份有限公司
Priority date: 2022-07-27
Filing date: 2022-07-27
Publication date: 2024-02-01

Abstract

Provided in the present application are a battery cell, a battery, and an electrical apparatus. The battery cell comprises: a casing, comprising a first wall and a second wall which are oppositely arranged in a first direction, a recessed part being provided on the outer surface of the first wall, a raised part being arranged at the position of the inner surface of the first wall corresponding to the recessed part, the raised part dividing the inner space of the casing into a first chamber and a second chamber which are arranged in a second direction, and the second direction being perpendicular to the first direction; a first electrode assembly, accommodated in the first chamber; a second electrode assembly, accommodated in the second chamber; and an electrode terminal, arranged on the first wall or the second wall, and connected to the first electrode assembly and the second electrode assembly, wherein in the first direction, the electrode terminal and the recessed part are correspondingly arranged. The technical solution of the present application effectively reduces the space occupancy rate of electrode terminals to the external space of battery cells, thus improving the capacity per gram of active substances in battery cells, and effectively raises the energy density of batteries.

Description

Battery cells, batteries and electrical devices

Technical field

The present application relates to the field of battery technology, specifically, to a battery cell, a battery and an electrical device.

Background technique

Energy conservation and emission reduction are the key to the sustainable development of the automobile industry. Electric vehicles have become an important part of the sustainable development of the automobile industry due to their advantages in energy conservation and environmental protection. For electric vehicles, battery technology is an important factor related to their development.

In the development of battery technology, how to improve the energy density of batteries is an urgent problem that needs to be solved.

Contents of the invention

The present application provides a battery cell, a battery and an electrical device, which can effectively increase the energy density of the battery.

In a first aspect, the application provides a battery cell, including: a casing, including a first wall and a second wall arranged oppositely along a first direction, the outer surface of the first wall is provided with a recess, and the inner surface of the first wall A convex part is provided at a position corresponding to the recessed part, and the convex part divides the internal space of the housing into a first cavity and a second cavity arranged along a second direction, and the second direction is perpendicular to the first direction; the first electrode assembly is accommodated in a first cavity; a second electrode assembly accommodated in the second cavity; an electrode terminal disposed on the first wall or the second wall, and the electrode terminal is connected to the first electrode assembly and the second electrode assembly; wherein, along the first direction, the electrode The terminals are arranged corresponding to the recessed parts.

In the technical solution of the present application, a recess is provided on the casing, and the electrode terminals correspond to the recess. When the battery cells of the battery are stacked along the first direction, the electrode terminals of the battery cells can be at least partially accommodated in or accommodated in the recess of the battery cells. in the recess of the battery cell adjacent to the battery cell, thereby effectively reducing the space occupied by the electrode terminals on the external space of the battery cell, effectively improving the structural compactness of the battery, and thus conducive to increasing the energy density of the battery; at the same time , the battery cell includes a first electrode assembly accommodated in the first cavity and a second electrode assembly accommodated in the second cavity, which is conducive to increasing the passenger capacity of the active material of the battery cell, thereby conducive to increasing the energy density of the battery; and , the electrode terminal is located between the first electrode assembly and the second electrode assembly, which is conducive to reducing and balancing the connection distance between the electrode terminal and the first electrode assembly and the electrode terminal and the second electrode assembly, thereby being conducive to reducing the connection distance between the electrode terminal and the first electrode The connection part between the assembly and the second electrode assembly occupies the space inside the casing, which is beneficial to increasing the occupancy rate of the main body of the electrode assembly to the space inside the casing, and is also conducive to increasing the energy density of the battery.

According to some embodiments of the present application, the first electrode assembly has a laminated structure, and the pole pieces of the first electrode assembly are stacked along the first direction; or the first electrode assembly has a wound structure, and the winding axis of the first electrode assembly perpendicular to the first direction.

In the above technical solution, the first electrode assembly is disposed flatly in the first cavity, so the expansion force of the first electrode assembly due to charging and discharging is mainly released in the first direction, effectively reducing the expansion of the first electrode assembly and the second electrode assembly. The deformation amount of a single battery cell caused by the superposition of forces can effectively save the pre-expansion space in a battery of the same capacity, thereby helping to increase the energy density of the battery.

According to some embodiments of the present application, the second electrode assembly has a laminated structure, and the pole pieces of the second electrode assembly are stacked along the first direction; or the second electrode assembly has a wound structure, and the winding of the second electrode assembly The axis is perpendicular to the first direction.

In the above technical solution, the second electrode assembly is disposed flatly in the first cavity, and the expansion force of the second electrode assembly due to charging and discharging is mainly released in the first direction, effectively reducing the expansion of the first electrode assembly and the second electrode assembly. The deformation amount of a single battery cell caused by the superposition of forces can effectively save the pre-expansion space in a battery of the same capacity, thereby helping to increase the energy density of the battery.

According to some embodiments of the present application, the electrode terminal is a sheet structure.

In the above technical solution, the electrode terminal has a sheet structure. The electrode terminal of the sheet structure has strong flexibility, flexibility and plasticity. On the one hand, the sheet electrode terminal can meet the requirements of stretching and bending, and can be directly Provides a larger connection surface to facilitate direct connection with the first electrode assembly and the second electrode assembly. It is not necessary to provide a dedicated adapter for connecting the electrode assembly and the electrode terminal in the housing, which is beneficial to saving the internal space of the housing and reducing the size of the electrode. The weight of the battery cells increases the energy density of the battery. At the same time, the sheet-shaped electrode terminals allow two adjacent battery cells to be directly connected through the electrode terminals, thereby further increasing the energy density of the battery by saving the weight and space requirements of the bus components.

According to some embodiments of the present application, the thickness of the electrode terminal is T1, 0.6mm≤T1≤2.5mm, preferably, 0.8mm≤T1≤2mm.

In the above technical solution, if the thickness T1 of the electrode terminal is less than 0.6mm, it will not only affect the overcurrent capability of the electrode terminal, but also affect the welding strength of the electrode terminal, and increase the process difficulty of the electrode terminal; and if the thickness T1 of the electrode terminal If it is greater than 2.5mm, there will be a large material redundancy, which is not conducive to reducing the weight and space occupancy of the electrode terminal, thereby affecting the energy density of the battery; the thickness T1 of the electrode terminal is designed to be between 0.6mm and 2.5mm, which can be While effectively ensuring the overcurrent capacity and connection strength of the electrode terminals, it also effectively ensures the energy density of the battery.

According to some embodiments of the present application, the first wall or the second wall is provided with an electrode lead-out hole, and the electrode terminal is penetrated through the electrode lead-out hole.

In the above technical solution, the first wall or the second wall of the casing is provided with an electrode lead-out hole, and the electrode terminal is passed through the electrode lead-out hole, so that one end of the electrode terminal extends into the inside of the casing and the other end is located outside the casing. The electrode lead-out hole is designed to facilitate Assembly of electrode terminals and housing.

According to some embodiments of the present application, the electrode terminal includes a first section, a second section and a third section. The first section is located inside the casing and connected to the electrode assembly, the third section is located outside the casing, and the second section is passed through the electrode lead. hole and connects the first and third sections.

In the above technical solution, the second end of the electrode terminal is inserted into the electrode lead-out hole, the first section is located inside the casing to facilitate connection with the electrode assembly, and the third section is located outside the casing to facilitate interconnection with the battery cells.

According to some embodiments of the present application, the first section and the third section extend in the same direction from the second section; or, the first section and the third section extend in opposite directions from the second section.

The above technical solution is conducive to reducing the height of the electrode terminal along the first direction while ensuring that the first section and the third section have sufficient connection area, thereby further reducing the space occupancy rate of the overall electrode terminal and conducive to improving the battery life. The energy density of the monomer is high, and the stability of the electrode terminal connection is effectively ensured.

According to some embodiments of the present application, the second section includes a fuse.

In the above technical solution, the second section is equipped with a fuse part. When the current of the battery cell is too large, the electrode terminal can fuse itself, thereby reducing the risk of thermal runaway combustion of the battery cell.

According to some embodiments of the present application, along the first direction, the height of the electrode terminal protruding from the outer surface of the housing is D1, and the depth of the recess is H1, D1/H1≤0.5, preferably, 0.1≤D1/H1≤0.5.

In the above technical solution, the ratio of the height D1 of the electrode terminal protruding from the outer surface of the casing to the depth H1 of the recess is less than or equal to 0.5, which facilitates embedding the electrode terminal into the recess of the battery cell or into adjacent cells after the batteries are grouped. In the recessed portion of the cell, the space occupation rate of the battery cell along the first direction is further reduced, the structural compactness of the battery is further improved, and the energy density of the battery is increased. At the same time, a certain space is provided between the electrode terminals and the shells of adjacent battery cells, thereby effectively reducing the risk of short circuits caused by overlapping of the electrode terminals and the shells of other battery cells, and effectively improving the safety performance of the battery.

According to some embodiments of the present application, along the third direction, the portion of the electrode terminal located outside the battery cell extends beyond the casing, and the third direction, the second direction and the first direction are vertical in pairs.

In the above technical solution, the part of the electrode terminal located outside the battery cell extends beyond the casing in the third direction, so as to reduce the connection distance between the electrode terminals of two adjacent battery cells when the battery cells are arranged in a group along the third direction. , thereby effectively reducing the size and space occupancy of the bus component, or two adjacent battery cells can be directly connected to each other through the part of the electrode terminal beyond the shell in the third direction, eliminating the need for bus components to further improve the compactness of the battery. , which will help improve the energy density of the battery.

According to some embodiments of the present application, the recessed portion extends along the third direction, and both ends of the recessed portion in the third direction respectively extend to both side edges of the housing in the third direction.

In the above technical solution, both ends of the recess along the third direction extend to both sides of the housing in the third direction respectively. When multiple battery cells are arranged along the third direction and connected to each other, the design of the recess is convenient for accommodating the extension of the electrode terminal. The part that comes out of the casing and the connection area where two adjacent battery cells are connected to each other can further reduce the space occupation rate of the battery by the electrode terminals and their connection areas. Moreover, the recessed part of this structure is convenient for protecting the connection area of the electrode terminals of two adjacent battery cells. When the battery is affected by impact force, deformation force and other forces, the recessed part can effectively reduce the resistance of the connection area of the electrode terminals. The risk of uncontrollable external forces is eliminated, thereby effectively improving the structural stability of the electrode terminal and the stability of the connection.

According to some embodiments of the present application, the size of the electrode terminal beyond the housing is D2, 2cm≤D2≤5cm, preferably, 3cm≤D2≤5cm.

In the above technical solution, the size of the electrode terminal beyond the casing is too small, which makes it inconvenient to connect the electrode terminal to other battery cells or components, and the stability of the electrode terminal connection cannot be guaranteed; and if the size of the electrode terminal beyond the casing is too large, then There will be a lot of redundant electrode terminals, which wastes electrode terminal materials and takes up a large space. Controlling the size D2 of the electrode terminal beyond the shell between 2cm and 5cm can effectively ensure the connection strength and stability of the electrode terminal. At the same time, it avoids the electrode terminals from taking up too much space and ensures the energy density of the battery.

According to some embodiments of the present application, along the second direction, the width of the recess is W1 and the length of the first wall is L, satisfying 0.1≤W1/L≤0.5.

In the above technical solution, the width direction of the recessed portion extends along the second direction. If the width of the recessed portion is too small, it will directly affect the accommodation of the electrode terminal by the recessed portion, which is not conducive to improving the structural compactness of the battery, or it will limit the direction of the pole along the second direction. The dimensions in both directions limit the overcurrent capacity of the electrode terminal; if the width of the recess is too large, it will affect the structural strength of the casing, and the casing will be more likely to deform after being stressed, thereby affecting the structural stability of the battery; The ratio of the width W1 in the two directions to the length L of the first wall along the second direction is limited to between 0.1 and 0.5, which can effectively ensure the energy density of the battery while protecting the structural stability of the battery.

According to some embodiments of the present application, along the second direction, the width of the electrode terminal is W2, the width of the recess is W1, W2/W1≤0.9, preferably, 0.7≤W2/W1≤0.9.

In the above technical solution, if the ratio of the width W2 of the electrode terminal to the width W1 of the recessed portion is too large, the recessed portion's accommodation of the electrode terminal will be reduced, and the compactness of the battery pack cannot be effectively ensured, which is not conducive to improving the energy density of the battery. Moreover, when the electrode terminal is accommodated in the recess, the electrode terminal and the wall in the width direction of the recess are prone to friction or contact, especially when the outer casing is deformed due to the expansion of the battery cells due to charge and discharge, impact force, or irresistible external force, the electrode terminal It is easy to make direct contact with the wall of the recess and cause a short circuit. Designing the ratio of the width W2 of the electrode terminal to the width W1 of the recess to be less than or equal to 0.9 can effectively ensure the accommodation of the electrode terminal by the recess, thereby ensuring the energy density of the battery, and can effectively reduce the risk of contact between the electrode terminal and the wall of the recess. risk, thereby improving the safety performance of the battery; at the same time, the ratio of the width W2 of the electrode terminal to the width W1 of the recessed portion is greater than or equal to 0.7 to ensure the overcurrent capability of the electrode terminal.

According to some embodiments of the present application, along the first direction, the depth of the recess is H1, the thickness of the shell is T2, 0.1≤H1/T2≤0.5, preferably, 0.3≤H1/T2≤0.5.

In the above technical solution, the depth of the recess extends along the first direction. If the depth of the recess is too small, it will directly affect the accommodation of the electrode terminal by the recess, and is not conducive to ensuring the adequacy of the gap between the electrode terminal and the housing in the first direction. , which is not conducive to improving the energy density and safety of the battery; if the depth of the recess is too large, it will affect the structural strength of the casing, and the casing will be more likely to deform after being stressed, thus affecting the structural stability of the battery; move the recess along the first The ratio of the depth H1 in the direction to the thickness T2 of the casing along the first direction is designed to be between 0.1 and 0.5, which can effectively ensure the energy density of the battery while protecting the structural stability and safety of the battery.

According to some embodiments of the present application, the battery cell further includes an insulating member, and the insulating member is used to insulate and isolate the electrode terminal and the casing.

In the above technical solution, the battery cells are designed with insulating parts that isolate the electrode terminals and the casing to avoid short circuits caused by contact between the electrode terminals and the casing, effectively ensuring the safety of the battery cells.

According to some embodiments of the present application, the electrode terminal is disposed on the first wall, and the electrode terminal is at least partially accommodated in the recess.

In the above technical solution, the electrode terminals are at least partially accommodated in the recess, thereby effectively reducing the space occupied by the electrode terminals in the external space of the battery cell, effectively improving the structural compactness of the battery, and thus helping to increase the energy density of the battery;

According to some embodiments of the present application, the first electrode assembly includes a first tab, the second electrode assembly includes a second tab, the first tab and the second tab have the same polarity, and the electrode terminal is connected to the first tab and the second tab. The two terminal tabs are connected, and the battery cell further includes: an insulating layer, which is disposed on the inner surface of the first wall at a position corresponding to the recess. The insulating layer is used to insulate and isolate the first wall and the first tab, and to insulate and isolate the first wall and the first tab. The second pole.

In the above technical solution, the electrode terminals can be directly connected to the tabs of the first electrode assembly and the second electrode assembly, which can effectively save adapters, thereby further improving the space utilization inside the casing and helping to increase the energy density of the battery cells. ;The electrode terminal is arranged on the first wall, and the part of the electrode terminal that extends into the shell is connected to the first and second tabs. An insulating layer is provided on the inner surface of the first wall corresponding to the recess, which can effectively avoid the first tab. When the second tab is connected to the electrode terminal close to the first wall, it overlaps with the first wall and a short circuit occurs, thereby effectively ensuring the safety performance of the battery cell.

According to some embodiments of the present application, the electrode terminal is disposed on the second wall, the first electrode assembly includes a first tab, the second electrode assembly includes a second tab, the first tab and the second tab have the same polarity, and the electrode The terminal is connected to the first tab and the second tab. The battery cell also includes: an insulating layer, which is provided on the inner surface of the second wall. The projection of the insulating layer on the first wall at least partially falls into the recess. The insulating layer is Insulating and isolating the second wall and the first tab and insulating and isolating the second wall and the second tab.

In the above technical solution, the electrode terminals are arranged on the second wall. When the battery cells are grouped, the electrode terminals can be accommodated in the grooves of adjacent battery cells to effectively increase the energy density of the battery; the electrode terminals and the first electrode assembly It can be directly connected to the tab of the second electrode assembly, which can effectively save adapters, thereby further improving the space utilization inside the casing and helping to increase the energy density of the battery cell; the electrode terminal is set on the second wall, and the electrode terminal extends The part that enters the shell is connected to the first and second tabs, and an insulating layer is provided on the inner surface of the second wall at a position corresponding to the recess, which can effectively prevent the first and second tabs from being close to the second wall and the electrode terminal. When connected, it overlaps with the second wall and causes a short circuit, thereby effectively ensuring the safety performance of the battery cells.

According to some embodiments of the present application, at least part of the first tab of the first electrode assembly and at least part of the second tab of the second electrode assembly are located between the protrusion and the second wall.

In the above technical solution, at least part of the first tab of the first electrode assembly and at least part of the second tab of the second electrode assembly are located between the convex part and the second wall, and at the same time, the positions of the electrode terminals and the recessed part correspond to each other, Then at least part of the electrode terminal, at least part of the first tab and at least part of the second tab share the space between the protrusion and the second wall of the housing along the second direction, thereby reducing the number of the first tab and the second wall. The occupation of the internal space of the casing by the diode tabs and electrode terminals is conducive to increasing the space occupancy rate of the main body of the electrode assembly, thereby further increasing the energy density of the battery cell.

According to some embodiments of the present application, the first wall and the second wall are walls with the largest area of the battery cell.

In the above technical solution, the first wall and the second wall are the large surfaces of the casing, that is to say, the electrode terminals are arranged on the large surfaces of the battery cells. Compared with the structure in which the electrode terminals are arranged on the narrow surfaces of the battery cells, it can effectively Ensure the size requirements of the recess and the electrode terminal, and ensure that after the battery cells are stacked, the recess can accommodate the electrode terminal of the battery cell where it is located or the electrode terminal of the adjacent battery cell to ensure the energy density of the battery.

According to some embodiments of the present application, the casing includes a third wall, the thickness direction of the third wall, the first direction and the second direction are perpendicular to each other, and the third wall is provided with an injection liquid for injecting electrolyte into the interior of the battery cell. hole.

In the above technical solution, the first electrode assembly and the second electrode assembly are arranged along the second direction, the thickness direction of the third wall is perpendicular to the second direction, and the liquid injection hole is provided on the third wall, which is beneficial to reducing and balancing the electrolyte. The infiltration distance to the first electrode assembly and the second electrode assembly increases the infiltration speed of the electrolyte into the first electrode assembly and the second electrode assembly.

According to some embodiments of the present application, along the thickness direction of the third wall, at least part of the projection of the liquid injection hole falls between the convex part and the second wall.

In the above technical solution, a convex part is provided at a position corresponding to the recessed part, and the convex part divides the internal space of the housing into a first cavity and a second cavity arranged along the second direction, and the first electrode assembly and the second electrode assembly are respectively arranged in the first cavity and the second cavity. In the first chamber and the second chamber, at least part of the projection of the liquid injection hole falls between the convex part and the second wall, then at least part of the liquid injection hole corresponds to the intermediate position of the first electrode assembly and the second electrode assembly, enabling electrolysis The liquid infiltrates from the middle of the first electrode assembly and the second electrode assembly into the first electrode assembly and the second electrode assembly, further improving the injection efficiency of the electrolyte.

According to some embodiments of the present application, the housing further includes two fourth walls oppositely arranged along the second direction, and the battery cell further includes: a pressure relief mechanism, and the pressure relief mechanism is provided on the fourth wall.

In the above technical solution, the electrode terminal is arranged on the first wall or the second wall opposite along the first direction, and the pressure relief mechanism is arranged on the fourth wall opposite along the second direction. When the battery cell undergoes thermal runaway, the battery cell The high-temperature and high-pressure gas flows toward the pressure relief mechanism in the second direction and is discharged through the pressure relief mechanism. The electrode terminals and the pressure relief mechanism are arranged on different walls of the battery cell, which can effectively reduce the risk of the electrode terminals being melted due to the high temperature flame of the battery cell. risk.

In a second aspect, the present application provides a battery, including at least one row of battery cells as described in any of the above solutions. Each row of battery cells includes a plurality of the battery cells. Each row of battery cells Two adjacent battery cells in the body are arranged along a third direction and are electrically connected to each other, and the third direction, the second direction and the first direction are perpendicular to each other.

According to some embodiments of the present application, the electrode terminal exceeds the outline of the housing along the third direction, and the electrode terminals of two adjacent battery cells are welded.

In the above technical solution, the electrode terminals extend beyond the outline of the casing along the third direction in which the battery cells are arranged, and the electrode terminals of two adjacent battery cells along the third direction are welded to each other, so that multiple battery cells are electrically connected to each other. Saving the use of bus components will help further improve the energy density of the battery.

According to some embodiments of the present application, the battery includes multiple rows of the battery cells, and the multiple rows of the battery cells are stacked along the first direction.

In the above technical solution, multiple rows of battery cells are stacked along the first direction, and the recessed portion of each row of battery cells can accommodate the electrode terminals of the row of battery cells or the electrode terminals of adjacent rows of battery cells, effectively improving the efficiency of the battery. The compact structure of multiple battery cells improves the energy density of the battery.

In a third aspect, this application also provides an electrical device, including the battery described in any of the above solutions, where the battery is used to provide electrical energy.

Description of drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required to be used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present application and therefore do not It should be regarded as a limitation of the scope. For those of ordinary skill in the art, other relevant drawings can be obtained based on these drawings without exerting creative efforts.

Figure 1 is a schematic structural diagram of a vehicle provided by some embodiments of the present application;

Figure 2 is an exploded view of a battery provided by some embodiments of the present application;

Figure 3 is a schematic diagram of the appearance and structure of a battery cell provided by some embodiments of the present application;

Figure 4 is a schematic diagram of the internal structure of the casing of a battery cell provided by some embodiments of the present application;

Figure 5 is a schematic diagram of the internal structure of a battery cell provided by some embodiments of the present application;

Figure 6 is a top view of the appearance of a battery cell provided by some embodiments of the present application;

Figure 7 is a cross-sectional view along the A-A direction shown in Figure 6;

Figure 8 is a cross-sectional view along B-B direction shown in Figure 6;

Figure 9 is a bottom view of Figure 6;

Figure 10 is a schematic diagram of the appearance and structure of a battery cell provided by some embodiments of the present application;

Figure 11 is a schematic diagram of the internal structure of a battery cell provided by some embodiments of the present application;

Figure 12 is a schematic structural diagram of the electrode terminal of the battery cell installed on the second wall according to some embodiments of the present application;

Figure 13 is a top view of the appearance of a battery cell provided by some further embodiments of the present application;

Figure 14 is a cross-sectional view along the C-C direction shown in Figure 13;

Figure 15 is a cross-sectional view along the D-D direction shown in Figure 13;

Figure 16 is a top view of Figure 13;

Figure 17 is a schematic structural diagram of an electrode terminal provided by some embodiments of the present application;

Figure 18 is a schematic structural diagram of an electrode terminal provided by some embodiments of the present application;

Figure 19 is a schematic structural diagram of an insulator provided by some embodiments of the present application;

Figure 20 is a schematic structural diagram of an insulator provided by some embodiments of the present application;

Figure 21 is a schematic diagram of the battery cell arrangement structure of the battery provided by some embodiments of the present application;

Figure 22 is a schematic diagram of the arrangement of battery cells from a first perspective of a battery provided by some embodiments of the present application;

Figure 23 is a schematic diagram of the arrangement of battery cells from a second perspective of a battery provided by some embodiments of the present application.

In the drawings, the drawings are not drawn to actual scale.

Marking description: 1000-vehicle; 100-battery; 10-battery cell; 11-casing; 111-first wall; 112-second wall; 113-concave portion; 114-convex portion; 115-first cavity; 116- second cavity; 117-electrode lead-out hole; 118-third wall; 119-fourth wall; 12-first electrode assembly; 121-first pole; 13-second electrode assembly; 131-second pole; 14-electrode terminal; 14a-first electrode terminal; 14b-second electrode terminal; 141-first section; 142-second section; 1421-fuse part; 143-third section; 144-connection surface; 15-insulation parts; 151-first insulation part; 152-second insulation part; 153-third insulation part; 16-insulation layer; 17-liquid injection hole; 18-pressure relief mechanism; 20-box; 21-first box body; 22-second box; 200-controller; 300-motor; X-first direction; Y-second direction; Z-third direction.

Detailed ways

In order to make the purpose, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments These are part of the embodiments of this application, not all of them. The components of the embodiments of the present application generally described and illustrated in the figures herein may be arranged and designed in a variety of different configurations.

Accordingly, the following detailed description of the embodiments of the application provided in the appended drawings is not intended to limit the scope of the claimed application, but rather to represent selected embodiments of the application. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the scope of protection of this application.

The embodiments of the technical solution of the present application will be described in detail below with reference to the accompanying drawings. The following examples are only used to illustrate the technical solution of the present application more clearly, and are therefore only used as examples and cannot be used to limit the protection scope of the present application.

Unless otherwise defined, all technical and scientific terms used herein have the same meanings as commonly understood by those skilled in the technical field belonging to this application; the terms used herein are for the purpose of describing specific embodiments only and are not intended to be used in Limitation of this application; the terms "including" and "having" and any variations thereof in the description and claims of this application and the above description of the drawings are intended to cover non-exclusive inclusion.

In the description of the embodiments of this application, the technical terms "first", "second", etc. are only used to distinguish different objects, and cannot be understood as indicating or implying the relative importance or implicitly indicating the quantity or specificity of the indicated technical features. Sequence or priority relationship. In the description of the embodiments of this application, "plurality" means two or more, unless otherwise explicitly and specifically limited.

Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the present application. The appearances of this phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. Those skilled in the art understand, both explicitly and implicitly, that the embodiments described herein may be combined with other embodiments.

In the description of the embodiments of this application, the term "plurality" refers to two or more (including two).

In the description of the embodiments of this application, the technical terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "back", "left", "right" and "vertical" The orientation or positional relationships indicated by "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. are based on those shown in the accompanying drawings. The orientation or positional relationship is only for the convenience of describing the embodiments of the present application and simplifying the description. It does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the implementation of the present application. Example limitations.

In the description of the embodiments of the present application, unless otherwise explicitly stated and limited, technical terms such as "setting", "installation", "connecting", "connecting" and "fixing" should be understood in a broad sense. For example, it can be a fixed connection, or a fixed connection. It can be a detachable connection or integrated; it can be a mechanical connection, an electrical connection, or a signal connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be an internal connection between two elements or an internal connection between two elements. interactive relationship. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of this application can be understood according to specific circumstances.

In the embodiments of the present application, the same reference numerals represent the same components, and for the sake of simplicity, detailed descriptions of the same components in different embodiments are omitted. It should be understood that the thickness, length, width and other dimensions of various components in the embodiments of the present application shown in the drawings, as well as the overall thickness, length and width of the integrated device, are only illustrative illustrations and should not constitute any limitation to the present application. .

In this application, the battery cells may include lithium ion secondary batteries, lithium ion primary batteries, lithium-sulfur batteries, sodium lithium ion batteries, sodium ion batteries or magnesium ion batteries, etc., which are not limited in the embodiments of this application. The battery cells may be in the shape of a flat body, a rectangular parallelepiped, or other shapes, and the embodiments of the present application are not limited to this.

The battery mentioned in the embodiments of this application refers to a single physical module including one or more battery cells to provide higher voltage and capacity. For example, the battery mentioned in this application may include a battery module or a battery pack. Among them, multiple battery cells can be connected in series, parallel or mixed connection to directly form a battery. Mixed connection means that multiple battery cells are connected in series and in parallel. Multiple battery cells can also be connected in series, parallel or mixed to form a battery cell group, and then multiple battery cell groups can be connected in series, parallel or mixed to form a battery. The battery may include a case for enclosing one or more battery cells. The box can prevent liquid or other foreign matter from affecting the charging or discharging of the battery cells.

The battery cell includes an electrode assembly and an electrolyte. The electrode assembly consists of a positive electrode plate, a negative electrode plate and a separator. Battery cells mainly rely on the movement of metal ions between the positive and negative electrodes to work. The positive electrode sheet includes a positive electrode current collector and a positive electrode active material layer. The positive electrode active material layer is coated on the surface of the positive electrode current collector. The positive electrode current collector that is not coated with the positive electrode active material layer protrudes from the positive electrode collector that is coated with the positive electrode active material layer. Fluid, the positive electrode current collector without the positive electrode active material layer is used as the positive electrode tab. Taking lithium-ion batteries as an example, the material of the positive electrode current collector can be aluminum, and the positive electrode active material can be lithium cobalt oxide, lithium iron phosphate, ternary lithium or lithium manganate, etc. The negative electrode sheet includes a negative electrode current collector and a negative electrode active material layer. The negative electrode active material layer is coated on the surface of the negative electrode current collector. The negative electrode current collector that is not coated with the negative electrode active material layer protrudes from the negative electrode collector that is coated with the negative electrode active material layer. Fluid, the negative electrode current collector that is not coated with the negative electrode active material layer serves as the negative electrode tab. The material of the negative electrode current collector can be copper, and the negative electrode active material can be carbon or silicon. In order to ensure that large currents can pass through without melting, the number of positive electrode tabs is multiple and stacked together, and the number of negative electrode tabs is multiple and stacked together. The material of the isolation film can be PP (polypropylene, polypropylene) or PE (polyethylene, polyethylene), etc. In addition, the electrode assembly may have a rolled structure or a laminated structure, and the embodiments of the present application are not limited thereto.

The battery cell also includes a casing and an electrode terminal. The electrode assembly is accommodated in the casing. The electrode terminal is installed in the casing and is electrically connected to the electrode assembly to export the electric energy of the electrode assembly.

With the development of battery technology, users have higher and higher demands for battery capacity. For example, with the continuous popularity of new energy vehicles, users' requirements for the cruising range of new energy vehicles continue to increase. Therefore, it is crucial to increase the energy density of batteries.

Batteries generally include a box and multiple battery cells housed in the box. Multiple battery cells can be connected in series, in parallel, or in mixed connection. Mixed connection means that multiple battery cells are connected in series and in parallel.

In the related art, electrode terminals generally protrude from the casing of the battery cells, and multiple battery cells are electrically connected to the electrode terminals of the battery cells through bus components.

However, the inventor found that the electrode terminals protruding from the casing would increase the size of the battery cells and occupy too much internal space of the box, and the busbar components would also occupy the internal space of the box, resulting in low space utilization of the box. , resulting in low energy density of the battery.

In view of this, in order to effectively improve the energy density of the battery, the present application provides a battery cell, which is provided with a recess on the outer surface of the first wall of the casing, and the inner surface of the first wall is at a position corresponding to the recess. A convex part is provided, and the convex part divides the internal space of the housing into a first cavity and a second cavity arranged along the second direction Y, and the first electrode assembly and the second electrode assembly are accommodated in the first cavity and the second cavity respectively. , the electrode terminal is arranged on the first wall or the second wall and corresponds to the position of the recess.

In the technical solution of the present application, a recess is provided on the casing, and the electrode terminals correspond to the recess. When the battery cells of the battery are stacked along the first direction X, the electrode terminals of the battery cells can be at least partially accommodated in the recess of the battery cell or It is accommodated in the recess of the battery cell adjacent to the battery cell, thereby effectively reducing the space occupied by the electrode terminals on the external space of the battery cell, thereby reducing the space occupied by the electrode terminals of multiple battery cells on the internal space of the battery box. The space occupancy rate effectively improves the structural compactness of the overall battery, which is beneficial to improving the energy density of the battery; at the same time, the battery cell includes a first electrode assembly accommodated in the first cavity and a second electrode assembly accommodated in the second cavity. , which is conducive to increasing the passenger capacity of the active material of the battery cell, and thus is conducive to increasing the energy density of the battery; and, the electrode terminal is located between the first electrode assembly and the second electrode assembly, which is conducive to reducing and balancing the relationship between the electrode terminal and the first electrode assembly. The connection distance between the electrode assembly and the electrode terminal and the second electrode assembly is conducive to reducing the space occupied by the connection part between the electrode terminal and the first electrode assembly and the second electrode assembly, which is conducive to improving the main body of the electrode assembly. The occupancy rate of the internal space of the casing is also conducive to improving the energy density of the battery.

The batteries disclosed in the embodiments of this application can be used in, but are not limited to, electrical equipment such as vehicles, ships, or aircrafts, and the batteries disclosed in this application can be used to form the power supply system of the electrical equipment.

Embodiments of the present application provide an electrical device that uses a battery as a power source. The electrical device may be, but is not limited to, a mobile phone, a tablet, a laptop, an electric toy, an electric tool, a battery car, an electric vehicle, a ship, a spacecraft, etc. Among them, electric toys can include fixed or mobile electric toys, such as game consoles, electric car toys, electric ship toys, electric airplane toys, etc., and spacecraft can include airplanes, rockets, space shuttles, spaceships, etc.

The battery described in the embodiments of the present application is not limited to the above-described electrical devices, but can also be applied to all electrical devices using batteries. However, for the sake of simplicity of description, the following embodiment uses an example of an embodiment of the present application. An electrical device is a vehicle as an example for illustration.

Please refer to FIG. 1 , which is a schematic structural diagram of a vehicle 1000 provided by some embodiments of the present application. The vehicle 1000 may be a fuel vehicle, a gas vehicle or a new energy vehicle, and the new energy vehicle may be a pure electric vehicle, a hybrid vehicle or an extended-range vehicle, etc. The battery 100 is disposed inside the vehicle 1000 , and the battery 100 may be disposed at the bottom, head, or tail of the vehicle 1000 . The battery 100 may be used to power the vehicle 1000 , for example, the battery 100 may serve as an 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 provide power to the motor 300 , for example, for starting, navigating and driving the vehicle 1000 .

In some other embodiments, the battery 100 can not only be used as an operating power source for the vehicle 1000 , but also can be used as a driving power source for the vehicle 1000 , replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000 .

As shown in Figure 2, Figure 2 shows an exploded view of the battery 100 provided by some embodiments of the present application. The battery 100 includes a battery cell 10 and a box 20. The battery cell 10 is accommodated in the box 20. The box 20 20 is used to provide accommodating space for the battery cell 10, and the box 20 can adopt a variety of structures. In some embodiments, the box 20 may include a first box 21 and a second box 22. The first box 21 and the second box 22 cover each other to form a battery 100 cavity, and the battery cell 10 is placed in the battery. 100 cavities. The shapes of the first box 21 and the second box 22 can be determined according to the shape of the battery cell 10 , and both the first box 21 and the second box 22 can have an opening. For example, both the first box 21 and the second box 22 can be hollow rectangular parallelepipeds and each has only one open surface. The openings of the first box 21 and the second box 22 are arranged oppositely, and the first box 21 and the second box 22 are open. The second boxes 22 are coupled with each other to form a box 20 with a closed chamber.

There may be one battery cell 10 or a plurality of battery cells 10 . If there are multiple battery cells 10 , the multiple battery cells 10 can be connected in series or in parallel or mixed together, and then the whole composed of the multiple battery cells 10 is accommodated in the box 20 , where the mixed connection is It means that the plurality of battery cells 10 are both connected in series and in parallel. Of course, multiple battery cells 10 may be first connected in series, parallel, or mixed to form a battery module, and then multiple battery modules may be connected in series, parallel, or mixed to form a whole, and be accommodated in the box 20 .

Please refer to Figures 3 to 16. Figure 3 is a schematic diagram of the appearance and structure of a battery cell provided by some embodiments of the present application; Figure 4 is a schematic diagram of the internal structure of the shell of a battery cell provided by some embodiments of the present application; Figure 5 is a schematic diagram of the structure of the battery cell provided by some embodiments of the present application. A schematic diagram of the internal structure of a battery cell provided in some embodiments of the application; Figure 6 is a top view of the appearance of a battery cell provided in some embodiments of the application; Figure 7 is a cross-sectional view along the A-A direction shown in Figure 6; Figure 8 is a diagram of Figure 6 The cross-sectional view along the B-B direction is shown; Figure 9 is a bottom view of Figure 6; Figure 10 is a schematic diagram of the appearance and structure of a battery unit provided by some further embodiments of the present application; Figure 11 is a battery unit provided by some further embodiments of the present application. A schematic diagram of the internal structure of the body; Figure 12 is a schematic structural diagram of a battery cell provided by some embodiments of the present application, with the electrode terminals installed on the second wall; Figure 13 is a top view of the appearance of a battery cell provided by some further embodiments of the present application; Figure 14 is a cross-sectional view along the C-C direction shown in Figure 13; Figure 15 is a cross-sectional view along the D-D direction shown in Figure 13; Figure 16 is a top view of Figure 13; Some embodiments of the present application provide a battery cell 10, The battery cell 10 includes a housing 11 , a first electrode assembly 12 , a second electrode assembly 13 and an electrode terminal 14 . The housing 11 includes a first wall 111 and a second wall 112 oppositely arranged along the first direction X. The first wall 111 The outer surface of the first wall 111 is provided with a recess 113, and the inner surface of the first wall 111 is provided with a protrusion 114 at a position corresponding to the recess 113. The protrusion 114 divides the internal space of the housing 11 into first cavities 115 arranged along the second direction Y. and the second cavity 116, the second direction Y is perpendicular to the first direction X.

The first electrode assembly 12 is accommodated in the first cavity 115 , and the second electrode assembly 13 is accommodated in the second cavity 116 . The electrode terminal 14 is disposed on the first wall 111 or the second wall 112, and is connected to the first electrode assembly 12 and the second electrode assembly 13; wherein, along the first direction X, the electrode terminal 14 is disposed corresponding to the recess 113.

Specifically, as shown in FIGS. 3 and 4 , the first wall 111 and the second wall 112 are arranged oppositely along the first direction X, and the first cavity 115 and the second cavity 116 are arranged along the second direction Y.

The housing 11 can have various structural forms. In some embodiments, the housing 11 may include a housing and a cover. The housing is a hollow structure with an opening on one side. The cover covers the opening of the housing and forms a sealed connection to form a structure for accommodating the battery cells 10 The sealed space of the electrode assembly, electrolyte and other related components.

Wherein, the housing 11 includes a first wall 111 and a second wall 112 that are oppositely arranged along the first direction Any wall portion of 11, in the embodiment in which “the housing 11 includes a shell and a cover”, the electrode terminal 14 may be provided on the cover. For example, when the electrode terminal 14 is disposed on the first wall 111, the first wall 111 may be a cover. When the electrode terminal 14 is disposed on the second wall 112, the second wall 112 may be a cover. Of course, the first wall 111 and the second wall 112 may both be wall portions of the housing.

The recessed portion 113 is recessed compared to the outer surface of the first wall 111 of the housing 11 , and a convex portion 114 is formed on the inner surface of the first wall 111 at a position corresponding to the recessed portion 113 . The shape of the recess 113 can be implemented in various ways. The recess 113 can extend to the edge of the housing 11 in a direction perpendicular to the first direction X. Of course, the side walls of the recess 113 can also be of a closed-loop type.

The convex part 114 divides the internal space of the housing 11 into a first cavity 115 and a second cavity 116 arranged along the second direction Y. The first cavity 115 and the second cavity 116 are in the space between the convex part 114 and the second wall 112 Connected everywhere.

The electrode assembly is the core component for realizing the charge and discharge function of the battery cell 10. The first electrode assembly 12 and the second electrode assembly 13 each include a positive electrode piece, a negative electrode piece and a separator. The separator is used to connect the positive electrode piece and the negative electrode piece. sheet insulation.

The electrode terminal 14 is used to connect with the electrode assembly to lead out the electric energy of the battery cell 10 . The electrode terminal 14 can be a columnar structure or a sheet structure.

The electrode terminal 14 can be directly connected to the first electrode assembly 12 or indirectly connected through an adapter or other components. Correspondingly, the electrode terminal 14 can be directly connected to the second electrode assembly 13 or indirectly connected through an adapter or other components. .

As shown in FIG. 3 , the electrode terminal 14 may include a first electrode terminal 14 a and a second electrode terminal 14 b with opposite polarities. The first electrode terminal 14 a and the second electrode terminal 14 b are both arranged corresponding to the recess 113 .

"The electrode terminal 14 is arranged corresponding to the recess 113" means that the electrode terminal 14 can be provided on the first wall 111 and installed on the bottom wall or side wall of the recess 113, and the electrode terminal 14 is fully or partially accommodated in the recess 113; or, the electrode The terminal 14 is mounted on the second wall 112 , and along the first direction X, the projection of the electrode terminal 14 on the first wall 111 at least partially falls into the recess 113 .

For example, as shown in FIG. 3 , the electrode terminal 14 is installed on the bottom wall of the recess 113 , and all the electrode terminals 14 are accommodated in the recess 113 .

In some embodiments, as shown in FIG. 10 , the electrode terminal 14 is installed on the second wall 112 , and along the first direction X, the projection of the electrode terminal 14 on the first wall 111 all falls into the recess 113 .

When the electrode terminal 14 is disposed on the first wall 111 , the electrode terminal 14 can be at least partially accommodated in the recess 113 of the battery cell 10 . When the electrode terminal 14 is disposed on the second wall 112 , the battery cell 10 of the battery 100 can be accommodated along the recess 113 of the battery cell 10 . After stacking in the first direction The compact structure is beneficial to improving the energy density of the battery 100; at the same time, the battery cell 10 includes the first electrode assembly 12 accommodated in the first cavity 115 and the second electrode assembly 13 accommodated in the second cavity 116, which is beneficial to improving the energy density of the battery 100. The passenger capacity of the active material of the battery cell 10 is conducive to increasing the energy density of the battery 100; and the electrode terminal 14 is located between the first electrode assembly 12 and the second electrode assembly 13, which is conducive to reducing and balancing the relationship between the electrode terminal 14 and the second electrode assembly 13. The connection distance between the first electrode assembly 12 and the electrode terminal 14 and the second electrode assembly 13 is beneficial to reducing the space occupied by the connecting portion of the electrode terminal 14 and the first electrode assembly 12 and the second electrode assembly 13 inside the housing 11 , which is beneficial to increasing the occupancy rate of the internal space of the housing 11 by the main body of the electrode assembly, and is also beneficial to increasing the energy density of the battery 100 .

At the same time, the setting of the recessed portion 113 plays a certain protective role in the electrode terminal 14 itself and the connection area of the electrode terminal 14 after the battery cells 10 are grouped, reducing the risk of the electrode terminal 14 enduring uncontrollable external forces, thereby effectively improving the structure of the electrode terminal 14 Stability and connection stability.

According to some embodiments of the present application, the first electrode assembly 12 has a laminated structure, and the pole pieces of the first electrode assembly 12 are stacked along the first direction The winding axis of 12 is perpendicular to the first direction X.

Specifically, the positive electrode tabs and the negative electrode tabs of the first electrode assembly 12 can be stacked along the first direction , the positive electrode piece or the negative electrode piece of the first electrode assembly 12 may also be a continuously bent and stacked structure. For example, the positive electrode piece of the first electrode assembly 12 is continuously bent and includes a plurality of stacked segments and a plurality of The bending sections, the plurality of laminated sections and the plurality of negative electrode sheets are alternately stacked along the first direction X, and each bending section connects two adjacent laminated sections.

In other embodiments, the first electrode assembly 12 may have a rolled structure, and the positive electrode piece and the negative electrode piece of the first electrode assembly 12 are rolled around the winding axis to form a rolled structure. The winding axis is perpendicular to the first direction X. By way of example, the winding axis may extend along the second direction Y.

The thickness direction of the first electrode assembly extends along the first direction , effectively reducing the deformation amount of a single battery cell 10 caused by the superposition of the expansion forces of the first electrode assembly 12 and the second electrode assembly 13. In a battery 100 of the same capacity, the pre-expansion space can be effectively saved, thereby conducive to improving the battery quality. 100 energy density.

According to some embodiments of the present application, the second electrode assembly 13 has a laminated structure, and the pole pieces of the second electrode assembly 13 are stacked along the first direction X; or the second electrode assembly 13 has a wound structure, and the second electrode assembly The winding axis of 13 is perpendicular to the first direction X.

Specifically, the positive electrode tab and the negative electrode tab of the second electrode assembly 13 can be stacked along the first direction X to form a laminated structure. The positive electrode tab and the negative electrode tab of the second electrode assembly 13 can both have a separate structure , the positive electrode piece or the negative electrode piece of the second electrode assembly 13 can also be a continuously bent and stacked structure. For example, the positive electrode piece of the second electrode assembly 13 is continuously bent and includes a plurality of stacked segments and a plurality of The bending sections, the plurality of laminated sections and the plurality of negative electrode sheets are alternately stacked along the first direction X, and each bending section connects two adjacent laminated sections.

In other embodiments, the second electrode assembly 13 may have a rolled structure, and the positive electrode piece and the negative electrode piece of the second electrode assembly 13 are rolled around the winding axis to form a rolled structure. The winding axis is perpendicular to the first direction X. By way of example, the winding axis may extend along the second direction Y.

It can be understood that the structures of the first electrode assembly 12 and the second electrode assembly 13 may be the same or different. For example, the first electrode assembly 12 and the second electrode assembly 13 may have a wound structure and a laminated structure. , as another example, the first electrode assembly 12 and the second electrode assembly 13 may both have a laminated structure or both may have a wound structure.

The second electrode assembly is disposed flatly in the first cavity 115, and the expansion force of the second electrode assembly 13 due to charging and discharging is mainly released along the first direction X, effectively reducing the stress of the first electrode assembly 12 and the second electrode assembly 13. The deformation amount of a single battery cell 10 caused by the superposition of expansion forces can effectively save the pre-expansion space in a battery 100 with the same capacity, thereby helping to increase the energy density of the battery 100 .

According to some embodiments of the present application, the electrode terminal 14 is a sheet-like structure.

The overall structure of the sheet-shaped electrode terminal 14 can be flat or bent. The cross-section of the bent electrode terminal 14 can be similar to an L-shaped structure, a Z-shaped structure, or a similar structure. U-shaped structure and so on.

The connection position of the sheet-shaped electrode terminal 14 with the first electrode assembly 12 and the second electrode assembly 13 may be located on the surface opposite to the thickness direction thereof, so as to effectively ensure the connection area of the electrode terminal 14 .

The sheet-shaped electrode terminal 14 has strong flexibility, flexibility and shapeability. On the one hand, the sheet-shaped electrode terminal 14 can meet the requirements of stretching and bending, and can provide a larger connection area. In some embodiments, , the first electrode assembly 12 and the second electrode assembly 13 are directly connected, and there is no need to provide a dedicated adapter for connecting the electrode assembly and the electrode terminal 14 in the housing 11, which is beneficial to saving the internal space of the housing 11 and reducing the battery cell size. The weight of the body 10 is thereby increased, thereby increasing the energy density of the battery 100 . At the same time, the sheet-shaped electrode terminals 14 allow two adjacent battery cells 10 to be directly connected through the electrode terminals 14 to further increase the energy density of the battery 100 by saving the weight and space requirements of bus components.

According to some embodiments of the present application, as shown in FIG. 3 , the thickness of the sheet-shaped electrode terminal 14 is T1, 0.6mm≤T1≤2.5mm, preferably, 0.8mm≤T1≤2mm.

The thickness T1 of the electrode terminal can be any value greater than or equal to 0.6mm and less than or equal to 2.5mm. For example, the thickness T1 of the electrode terminal 14 can be 0.6mm, 0.7mm, 1mm, 1.5mm, 2.1mm, 2.3mm, 2.5mm, etc. .

Preferably, the thickness T1 of the electrode terminal 14 can be any value greater than or equal to 0.8mm and less than or equal to 2mm. For example, the thickness T1 of the electrode terminal 14 can be 0.8mm, 0.9mm, 1.2mm, 1.4mm, 1.6mm, 1.8mm. , 2mm, etc.

For example, the thickness T1 of the electrode terminal 14 is 2 mm.

If the thickness T1 of the electrode terminal 14 is less than 0.6mm, it will not only affect the overcurrent capability of the electrode terminal 14, but also affect the welding strength of the electrode terminal 14, and increase the process difficulty of the electrode terminal 14; and if the thickness T1 of the electrode terminal 14 Greater than 2.5mm, there will be a large material redundancy, which is not conducive to reducing the weight and space occupation rate of the electrode terminal 14, thereby affecting the energy density of the battery 100; the thickness T1 of the electrode terminal 14 is designed to be between 0.6mm and 2.5mm. , which can effectively ensure the overcurrent capability and connection strength of the electrode terminal 14 and at the same time effectively ensure the energy density of the battery 100 .

According to some embodiments of the present application, the first wall 111 or the second wall 112 is provided with an electrode lead-out hole 117, and the electrode terminal 14 is penetrated through the electrode lead-out hole 117.

Specifically, in some embodiments, please refer to FIGS. 7 and 8 , the electrode terminal 14 is disposed on the first wall 111 , and the electrode lead-out hole 117 is disposed on the first wall 111 . At this time, the electrode lead-out hole 117 may be located in the recess 113 The bottom wall may also be located on the side wall of the recess 113. For example, the electrode lead-out hole 117 is located on the bottom wall of the recess 113.

In some embodiments, please refer to FIGS. 14 and 15 , the electrode terminal 14 is provided on the second wall 112 , and the electrode lead-out hole 117 is provided on the second wall 112 .

The first wall 111 or the second wall 112 of the housing 11 is provided with an electrode lead-out hole 117, and the electrode terminal 14 is passed through the electrode lead-out hole 117, so that one end of the electrode terminal 14 extends into the inside of the housing 11, and the other end is located outside the housing 11, and the electrode leads out The design of the hole 117 facilitates the assembly of the electrode terminal 14 and the housing 11 .

According to some embodiments of the present application, please refer to Figures 17 and 18. Figure 17 is a schematic structural diagram of an electrode terminal provided by some embodiments of the present application; Figure 18 is a schematic structural diagram of an electrode terminal provided by still further embodiments of the present application. The electrode terminal 14 includes a first section 141, a second section 142 and a third section 143. The first section 141 is located inside the housing 11 and connected to the electrode assembly. The third section 143 is located outside the housing 11. The second section 142 is inserted through the electrode. The lead hole 117 connects the first section 141 and the third section 143 .

The structural shapes of the first section 141, the second section 142, and the third section 143 of the electrode terminal can have various implementation forms, and the shapes and structures of the first section 141, the second section 142, and the third section 143 can be the same or different. , for example, the second segment 142 may be a columnar structure, the first segment 141 and the third segment 143 may be a sheet structure, etc., for example, the first segment 141, the second segment 142, and the third segment 143 are all sheet structures. shape structure.

The first section 141, the second section 142 and the third section 143 may extend in the same direction or in different directions.

The second end of the electrode terminal passes through the electrode lead-out hole 117 . The first section 141 is located inside the housing 11 to facilitate connection with the electrode assembly. The third section 143 is located outside the housing 11 to facilitate connection with the battery cell 10 .

According to some embodiments of the present application, the first section 141 and the third section 143 extend in the same direction from the second section 142; or, the first section 141 and the third section 143 extend in opposite directions from the second section 142.

It can be understood that the extending direction of the first section 141 and the third section 143 intersects the extending direction of the second section 142 (the connection direction of the first section 141 and the third section 143). For example, the extension direction of the first section 141 and the third section 143 may be perpendicular to the extension direction of the second section 142 .

When the extension direction of the first section 141 and the third section 143 is perpendicular to the extension direction of the second section 142, the electrode terminal 14 can extend in the same direction to form a U-shaped structure, and the electrode terminal 14 can also extend in the opposite direction to form a similar U-shaped structure. Z-shaped structure.

Illustratively, as shown in FIG. 17 , the first section 141 , the second section 142 and the third section 143 of the electrode terminal 14 are all sheet-like structures. The second section 142 extends along the first direction X, and the first section 141 and The third section 143 extends in the same direction to form a U-shaped structure. The thickness of the first section 141 and the third section 143 extends along the first direction X. The surface of the first section 141 away from the second section 142 is formed in contact with the first electrode assembly 12 The connection surface 144 is connected to the second electrode assembly 13 .

For example, as shown in FIG. 18 , the first section 141 , the second section 142 and the third section 143 of the electrode terminal 14 are all sheet-like structures. The second section 142 extends along the first direction X, and the first section 141 and The third section 143 extends in opposite directions to form a Z-shaped structure. The thicknesses of the first section 141 and the third section 143 extend along the first direction X. The surface of the first section 141 away from the second section 142 is formed in contact with the first electrode assembly 12 The connection surface 144 is connected to the second electrode assembly 13 .

The first section 143 and the third section 143 extend in the same or opposite directions, which is beneficial to reducing the height of the electrode terminal 14 along the first direction X while ensuring that the first section 141 and the third section 143 have sufficient connection surfaces 144 This will further reduce the space occupation rate of the overall electrode terminal 14, help improve the energy density of the battery cell 10, and effectively ensure the connection stability of the electrode terminal 14.

According to some embodiments of the present application, please continue to refer to FIGS. 17 and 18 , the second section 142 includes a fuse portion 1421 .

The fuse part 1421 refers to a part with a small overcurrent capability. When the current is too large, the fuse part 1421 can melt itself to cut off the electrical connection of the electrode terminal 14, thereby effectively reducing the risk of thermal runaway of the battery cell 10.

There is a positive correlation between the overcurrent capability of the electrode terminal 14 and the overcurrent cross-sectional area of the electrode terminal 14. Therefore, by reducing the overcurrent cross-sectional area of a certain section of the second section 142, this section can form the fuse portion of the second section 142. 1421, the fuse portion 1421 can be implemented in a variety of structures, such as reducing the width and/or thickness of the segment to reduce the cross-sectional area of the segment to form the fuse portion 1421. For another example, one or more through holes can be opened in the segment to reduce the cross-sectional area of the segment to form the fuse portion 1421.

Exemplarily, the second section 142 has a sheet-like structure, and the second section 142 is provided with a through hole that runs through the second section 142 along its thickness direction. The cross-sectional area of the second section 142 corresponding to the location of the through hole decreases. The fuse portion 1421 of the second section 142 is formed.

The second section is provided with a fuse part 1421. When the current of the battery cell 10 is too large, the electrode terminal 14 can fuse itself, thereby reducing the risk of thermal runaway combustion of the battery cell 10.

According to some embodiments of the present application, please refer to Figures 9 and 16 again. Along the first direction , preferably, 0.1≤D1/H1≤0.5.

It can be understood that, as shown in FIG. 9 , when the electrode terminal 14 is installed in the recess 113 of the first wall 111 , D1 is the height of the electrode terminal 14 protruding from the bottom wall of the recess 113 .

As shown in FIG. 16 , when the electrode terminal 14 is installed on the second wall 112 , D1 is the height of the electrode terminal 14 protruding from the second wall 112 .

The depth of the recessed portion 113 extends along the first direction numerical value.

Preferably, the ratio of D1/H1 is greater than 0.1 to facilitate the operation of connecting multiple battery cells 10 through the electrode terminals 14. For example, the ratio of D1/H1 is 0.2.

For example, D1 can be a value greater than or equal to 0.5mm and less than or equal to 7mm. For example, D1 can be 0.5mm, 1mm, 2mm, 4mm, 5mm, etc. H1 can be a value greater than or equal to 10mm and less than or equal to 50mm. For example, H1 can be 10mm, 15mm, 35mm, 50mm, etc.

The ratio of the height D1 of the electrode terminal protruding from the outer surface of the casing 11 to the depth H1 of the recess 113 is less than or equal to 0.5, which facilitates embedding the electrode terminal 14 into the recess 113 of the battery cell 10 where it is located, or embedding it into adjacent cells after the batteries 100 are grouped. In the recess 113 of the battery cell 10 , the space occupation rate of the battery cell 10 along the first direction X is further reduced, the structural compactness of the battery 100 is further improved, and the energy density of the battery 100 is improved. At the same time, a certain space is provided between the electrode terminal 14 and the casing 11 of the adjacent battery cell 10 , thereby effectively reducing the risk of a short circuit due to overlap between the electrode terminal 14 and the casing 11 of other battery cells 10 , and effectively improving the efficiency of the battery 100 safety performance.

According to some embodiments of the present application, please refer to Figures 3 and 10. Along the third direction Z, the portion of the electrode terminal 14 located outside the battery cell 10 exceeds the housing 11. The third direction Z, the second direction Y and the first direction X pairs are vertical.

Based on the implementation form of "the electrode terminal 14 includes a first section 141, a second section 142 and a third section 143", the third section 143 extends along the third direction Z, and one end of the third section 143 away from the second section 142 extends along the third direction Z. Three directions Z extend beyond the housing 11.

The portion of the electrode terminal 14 located outside the battery cell 10 extends beyond the housing 11 along the third direction Z, so that when the battery cells 10 are arranged in a group along the third direction Z, the electrode terminals 14 of two adjacent battery cells 10 can be lowered. The connection distance effectively reduces the size and space occupancy of the bus component, or two adjacent battery cells 10 can be directly connected to each other through the portion of the electrode terminal 14 extending beyond the housing 11 along the third direction Z, eliminating the need for bus components. The compact structure of the battery 100 is further improved, thereby helping to increase the energy density of the battery 100 .

According to some embodiments of the present application, as shown in FIGS. 3 and 10 , the recess 113 extends along the third direction Z, and both ends of the recess 113 in the third direction Z respectively extend to both ends of the housing 11 in the third direction Z. Side edges.

The portion of the electrode terminal located outside the housing 11 extends beyond the housing 11 along the third direction Z, and both ends of the recess 113 along the third direction Z extend to both sides of the housing 11 in the third direction Z, so as to facilitate the connection of the electrode terminal 14 The portion outside the housing 11 is accommodated in the recess 113 as much as possible.

When multiple battery cells 10 are arranged along the third direction Z and connected to each other, the design of the recessed portion 113 facilitates accommodating the portion of the electrode terminal 14 extending out of the housing 11 and the connection area where two adjacent battery cells 10 are connected to each other, thereby further The space occupied by the electrode terminals 14 and their connection areas on the battery 100 is reduced. Moreover, the recessed portion 113 of this structure is convenient for protecting the connection area of the electrode terminals 14 of two adjacent battery cells 10. When the battery 100 is affected by impact force, deformation force, etc., the recessed portion 113 can effectively lower the electrode. The connection area of the terminal 14 is exposed to the risk of uncontrollable external forces, thereby effectively improving the structural stability and connection stability of the electrode terminal 14 .

According to some embodiments of the present application, please refer to FIG. 6 again, the size of the electrode terminal 14 beyond the housing 11 is D2, 2cm≤D2≤5cm, preferably, 3cm≤D2≤5cm.

Specifically, the size of the portion of the electrode terminal 14 located outside the battery cell 10 beyond the housing 11 along the third direction Z is D2. D2 can be any value greater than or equal to 2cm and less than or equal to 5cm. For example, D2 can be 2cm or 3cm. , 4cm, 4.6cm, 5cm, etc.

Preferably, D2 can be any value greater than or equal to 3cm and less than or equal to 5cm. For example, D2 can be 3cm, 3.5cm, 4.2cm, 4.8cm, 5cm, etc.

For example, D2 is 5cm.

If the electrode terminal 14 exceeds the size of the housing 11 by being too small, it will be inconvenient to connect the electrode terminal 14 to other battery cells 10 or components, and the stability of the connection of the electrode terminal 14 cannot be guaranteed; and if the size of the electrode terminal 14 exceeds the size of the housing 11 by too much If the electrode terminal 14 is larger, there will be more redundant electrode terminals 14, which wastes the material of the electrode terminal 14 and takes up a large space. Controlling the size D2 of the electrode terminal 14 beyond the shell 11 to between 2cm and 5cm can effectively ensure While improving the connection strength and stability of the electrode terminals 14 , the electrode terminals 14 are prevented from occupying too much space, and the energy density of the battery 100 is ensured.

According to some embodiments of the present application, along the second direction Y, please continue to refer to FIG. 6 , the width of the recess 113 is W1, and the length of the first wall 111 is L, satisfying 0.1≤W1/L≤0.5.

Specifically, the direction of the width W1 of the recessed portion 113 extends along the second direction Y, and the direction of the length L of the first wall 111 extends along the second direction Y. The ratio of W1/L can be any value greater than or equal to 0.1 and less than or equal to 0.5. For example, W1/L can be 0.1, 0.2, 0.3, 0.4, 0.5, etc.

Preferably, the ratio of W1/L can be any value greater than or equal to 0.15 and less than or equal to 0.35. For example, W1/L can be 0.15, 0.18, 0.21, 0.32, 0.35, etc. For example, W1/L may be 0.35.

For example, W1 can be any value greater than or equal to 15mm and less than or equal to 50mm. For example, W1 can be 15mm, 20mm, 45mm, 50mm, etc. L can be any value greater than or equal to 80mm and less than or equal to 300mm. For example, L can be For 80mm, 100mm, 200mm, 300mm, etc. Of course, W1 and L can also be any values in other ranges.

If the width of the recessed portion 113 is too small, it will directly affect the accommodation of the electrode terminal 14 by the recessed portion 113 , which is not conducive to improving the structural compactness of the battery 100 , or it will limit the size of the pole along the second direction Y, thereby limiting the electrode terminal 14 The overcurrent capability; if the width of the recess 113 is too large, it will affect the structural strength of the casing 11, and the casing 11 will be more easily deformed after being stressed, thereby affecting the structural stability of the battery 100; The ratio of the width W1 to the length L of the first wall 111 along the second direction Y is limited to between 0.1 and 0.5, which can effectively ensure the energy density of the battery 100 while protecting the structural stability of the battery 100 .

According to some embodiments of the present application, please continue to refer to FIG. 6 , along the second direction Y, the width of the electrode terminal 14 is W2, the width of the recess 113 is W1, W2/W1≤0.9, preferably, 0.7≤W2/W1≤ 0.9.

Specifically, the direction of the width W2 of the electrode terminal 14 extends in the second direction Y, and the direction of the width W1 of the recessed portion 113 extends in the second direction Y. The ratio of W2/W1 can be any value less than or equal to 0.9. For example, W2/W1 can be 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, etc.

Preferably, the ratio of W2/W1 can be any value greater than or equal to 0.7 and less than or equal to 0.9. For example, W2/W1 can be 0.7, 0.72, 0.75, 0.81, 0.85, 0.9, etc. For example, W2/W1 is 0.85.

For example, W1 can be a value greater than or equal to 15mm and less than or equal to 50mm. For example, W1 can be 15mm, 20mm, 45mm, 50mm, etc. W2 can be a value greater than or equal to 8mm and less than or equal to 45mm. For example, W2 can be 8mm. , 10mm, 40mm, etc.

If the ratio of the width W2 of the electrode terminal 14 to the width W1 of the recessed portion 113 is too large, the recessed portion 113 will be less able to accommodate the electrode terminal 14 and the compactness of the assembled battery 100 cannot be effectively ensured, which is not conducive to improving the energy density of the battery 100 , and when the electrode terminal 14 is accommodated in the recess 113, the electrode terminal 14 and the wall in the width direction of the recess 113 are prone to friction or contact, especially when the casing 11 expands due to charging and discharging of the battery cell 10, impact force, and irresistible external force. When deformation occurs due to the influence, the electrode terminal 14 is likely to be in direct contact with the wall of the recessed portion 113 to cause a short circuit. Designing the ratio of the width W2 of the electrode terminal 14 to the width W1 of the recessed portion 113 to be less than or equal to 0.9 can effectively ensure the accommodation degree of the recessed portion 113 for the electrode terminal 14, thereby ensuring the energy density of the battery 100, and can effectively reduce the distance between the electrode terminal 14 and The risk of contact with the wall of the recess 113 is thereby improved, thereby improving the safety performance of the battery 100; at the same time, the ratio of the width W2 of the electrode terminal 14 to the width W1 of the recess 113 is greater than or equal to 0.7 to ensure the overcurrent capability of the electrode terminal 14.

According to some embodiments of the present application, please refer to Figure 9 again. Along the first direction ≤0.5.

Specifically, the depth H1 of the recess 113 and the thickness T2 of the housing 11 both extend along the first direction X. The ratio of the depth H1 of the recess 113 to the thickness T2 of the housing 11 may be greater than or equal to 0.1 and less than or equal to 0.5. Any value, for example, H1/T2 can be 0.1, 0.2, 0.3, 0.4, 0.5, etc.

Preferably, the ratio of the depth H1 of the recess 113 to the thickness T2 of the housing 11 can be any value greater than or equal to 0.3 and less than or equal to 0.5. For example, H1/T2 can be 0.3, 0.32, 0.35, 0.45, 0.5, etc. For example, the ratio of H1/T2 is 0.4.

For example, H1 can be a value greater than or equal to 5mm and less than or equal to 25mm. For example, H1 can be 5mm, 6mm, 20mm, 25mm, etc. T2 can be a value greater than or equal to 15mm and less than or equal to 50mm. For example, T2 can be 15mm. , 20mm, 40mm, 50mm, etc.

If the depth of the recessed portion 113 is too small, it will directly affect the accommodation of the electrode terminal 14 by the recessed portion 113 , and is not conducive to ensuring the adequacy of the gap between the electrode terminal 14 and the housing 11 in the first direction X, thereby being conducive to improving the performance of the battery 100 Energy density and safety; if the depth of the recess 113 is too large, it will affect the structural strength of the casing 11, and the casing 11 will be more easily deformed after being stressed, thereby affecting the structural stability of the battery 100; move the recess 113 along the first direction X The ratio of the depth H1 to the thickness T2 of the housing 11 along the first direction

According to some embodiments of the present application, the battery cell 10 further includes an insulating member 15 used to insulate and isolate the electrode terminal 14 and the housing 11 .

The insulating member is used to insulate the isolation electrode terminal 14 and the housing 11. The insulating member 15 can be made of plastic or insulating ceramics with good insulation performance. The structure, location and installation method of the insulating member 15 can have various implementation forms. It is sufficient to isolate the electrode terminal 14 and the housing 11 at the interface between the electrode terminal 14 and the housing 11 so that the electrode terminal 14 is not in conductive contact with the housing 11 .

Based on the implementation form of "the first wall 111 or the second wall 112 is provided with an electrode lead-out hole 117, and the electrode terminal 14 is inserted through the electrode lead-out hole 117", the insulating member 15 can be sleeve-shaped and placed around the outer periphery of the electrode terminal 14 and located at Between the inner wall of the electrode lead-out hole 117 and the outer peripheral surface of the electrode terminal 14, the electrode terminal 14 and the housing 11 are insulated.

Please refer to Figures 15 to 18, and further refer to Figures 19 and 20. Figure 19 is a schematic structural diagram of an insulating member provided by some embodiments of the present application; Figure 20 is a schematic structural diagram of an insulating member provided by still other embodiments of the present application. Based on the implementation form that "the electrode terminal 14 includes a first section 141, a second section 142, and a third section 143", the insulating member 15 can also include a first insulating portion 151, a second insulating portion 152, and a third insulating portion 153. The second insulating part 152 connects the first insulating part 151 and the third insulating part 153. The second insulating part 152 is disposed in the electrode lead-out hole 117. The second insulating part 152 includes a through hole for the second section 142 to pass through. The insulating part 151 is provided between the first section 141 and the inner surface of the housing 11 , and the third insulating part 153 is provided between the third section 143 and the outer surface of the housing 11 .

As shown in FIGS. 17 and 20 , when the first section 141 and the third section 143 extend in the same direction to form a U-like structure, the first insulating portion 151 and the third insulating portion 153 can also extend in the same direction to form a U-like structure. .

As shown in FIGS. 18 and 19 , when the first section 141 and the third section 143 extend in opposite directions to form a Z-like structure, the first insulating portion 151 and the third insulating portion 153 can also extend in opposite directions to form a Z-like structure. , In this way, the insulating member 15 not only plays an insulating role, but also plays a supporting role for the first section 141 and the third section 143 .

Among them, the insulating member 15 can be assembled on the housing 11 , and the insulating member 15 can also be injection molded on the housing 11 .

The battery 100 cell is designed to insulate the electrode terminal 14 and the insulating member 15 of the casing 11 to avoid short circuit caused by contact between the electrode terminal 14 and the casing 11, effectively ensuring the safety of the battery cell 10.

According to some embodiments of the present application, please refer to FIGS. 3 to 9 again, the electrode terminal 14 is disposed on the first wall 111 , and the electrode terminal 14 is at least partially accommodated in the recess 113 .

The electrode terminal is provided on the first wall 111 . The electronic terminal can be installed on the bottom wall of the recess 113 or on the side wall of the recess 113 . For example, the electrode terminal 14 is installed on the bottom wall of the recess 113 .

Based on the implementation of "the electrode terminal 14 is inserted into the electrode lead-out hole 117", the electrode lead-out hole 117 may be provided on the bottom wall of the recessed part 113 or on the side wall of the recessed part 113. For example, the electrode lead-out hole 117 is provided on the bottom wall of the recess 113 .

If the electrode terminal is disposed on the first wall 111, at least part of the electrode terminal 14 can be accommodated in the recess 113 of the battery cell 10, thereby effectively reducing the space occupation rate of the electrode terminal 14 in the external space of the battery cell 10, and effectively improving the The compact structure of the battery 100 is beneficial to improving the energy density of the battery 100;

According to some embodiments of the present application, as shown in FIGS. 5 to 8 , the first electrode assembly 12 includes a first tab 121 , the second electrode assembly 13 includes a second tab 131 , the first tab 121 and the second electrode The lugs 131 have the same polarity, and the electrode terminal 14 is connected to the first lug 121 and the second lug 131 . The battery cell 10 also includes: an insulating layer 16 disposed on the inner surface of the first wall 111 at a position corresponding to the recess 113 , the insulating layer 16 is used to insulate and isolate the first wall 111 and the first tab 121 and to insulate and isolate the first wall 111 and the second tab 131 .

The electrode terminal connects the first tab 121 and the second tab 131 , so that the electrode terminal 14 is connected to the first electrode assembly 12 and the second electrode assembly 13 .

It can be understood that the first electrode assembly 12 may also include a third electrode, and the second electrode assembly 13 may also include a fourth electrode. The third electrode and the fourth electrode have the same polarity and are the same as the first electrode. The polarity of the ear 121 is opposite. Based on the implementation form of "the electrode terminal 14 includes a first electrode terminal 14a and a second electrode terminal 14b", the first electrode terminal 14a is connected to the first electrode 121 and the second electrode 131, and the second electrode 14a is connected to the first electrode 121 and the second electrode 131. The electrode terminal 14b is connected to the third tab and the fourth tab.

In order to facilitate the connection between the electrode terminal 14 and the first tab 121 and the second tab 131 and effectively shorten the connection distance of the electrode terminal 14 , the first tab 121 can be disposed on a side of the first electrode assembly 12 close to the second electrode assembly 13 side, the second tab 131 may be disposed on a side of the second electrode assembly 13 close to the first electrode assembly 12 .

The insulating layer 16 is disposed on the inner surface of the first wall 111 at a position corresponding to the recessed portion 113 , which means that the insulating layer 16 is disposed on the outer surface of the convex portion 114 . The insulating layer 16 may be an insulating coating coated on the outer surface of the protrusion 114 .

The electrode terminal 14 extends into the housing 11 through the bottom wall or side wall of the recess 113 and is connected to the first tab 121 and the second tab 131. The insulating layer 16 is provided on the outer surface of the protruding portion 114, which can effectively prevent the first tab from being blocked. 121 contacts the protruding portion 114 of the second tab 131 to cause a short circuit.

The electrode terminal 14 can be directly connected to the tabs of the first electrode assembly 12 and the second electrode assembly 13, which can effectively save adapters, thereby further improving the space utilization inside the housing 11 and helping to increase the energy density of the battery cell 10. ; The electrode terminal 14 is arranged on the first wall 111. The portion of the electrode terminal 14 extending into the housing 11 is connected to the first tab 121 and the second tab 131. An insulating layer is provided on the inner surface of the first wall 111 at a position corresponding to the recess 113. 16. It can effectively prevent the first tab 121 and the second tab 131 from overlapping the first wall 111 and causing a short circuit when they are connected to the electrode terminal 14 close to the first wall 111, thereby effectively ensuring the safety performance of the battery cell 10.

According to some embodiments of the present application, please refer to FIGS. 11 to 15 , the electrode terminal 14 is disposed on the second wall 112 , the first electrode assembly 12 includes a first tab 121 , and the second electrode assembly 13 includes a second tab 131 . The first tab 121 and the second tab 131 have the same polarity. The electrode terminal 14 is connected to the first tab 121 and the second tab 131 . The battery cell 10 also includes: an insulating layer 16 disposed on the second wall 112 On the inner surface, the projection of the insulating layer 16 on the first wall 111 at least partially falls into the recess 113 , and the insulating layer 16 is used to insulate and isolate the second wall 112 and the first tab 121 and to insulate and isolate the second wall 112 and the second pole. Ear 131.

The electrode terminal 14 is disposed on the second wall 112. Along the first direction At least part of it falls into the recess 113 .

The electrode terminals are arranged on the second wall 112. When the battery cells 10 are grouped, the electrode terminals 14 can be accommodated in the grooves of adjacent battery cells 10 to effectively increase the energy density of the battery 100; the electrode terminals 14 and the first electrode The tabs of the component 12 and the second electrode component 13 are directly connected, which can effectively save adapters, thereby further improving the space utilization inside the casing 11 and conducive to increasing the energy density of the battery cell 10; the electrode terminal 14 is arranged on the second Wall 112, the portion of the electrode terminal 14 extending into the housing 11 is connected to the first tab 121 and the second tab 131. An insulating layer 16 is provided on the inner surface of the second wall 112 at a position corresponding to the recess 113, which can effectively avoid the first pole. When the lug 121 and the second pole lug 131 are connected to the electrode terminal 14 close to the second wall 112, they overlap with the second wall 112 and cause a short circuit, thereby effectively ensuring the safety performance of the battery cell 10.

According to some embodiments of the present application, as shown in FIGS. 7 and 14 , at least part of the first tab 121 of the first electrode assembly 12 and at least part of the second tab 131 of the second electrode assembly 13 are located on the protrusion 114 and the second wall 112.

As mentioned above, in order to effectively shorten the connection distance of the electrode terminal 14, the first tab 121 can be disposed on the side of the first electrode assembly 12 close to the second electrode assembly 13, and the second tab 131 can be disposed on the second electrode. The side of the component 13 close to the first electrode component 12 .

At least part of the first pole 121 and the second pole 131 are located between the protrusion 114 and the second wall 112. The first pole 121 and the second pole 131 may be offset from each other along the first direction X. Of course, the first pole 121 and the second pole 131 may be offset from each other along the first direction X. One pole tab 121 and the second pole tab 131 may also be stacked along the first direction X. Exemplarily, as shown in FIG. 11 , both the first pole tab 121 and the second pole tab 131 are multi-layer structures, and the first pole tab 121 and the second pole tab 131 are located between the protruding portion 114 and the second wall 112 parts are alternately stacked along the first direction X.

Based on the implementation form that "the electrode terminal 14 has a sheet structure", as shown in Figure 15, the portion of the electrode terminal 14 extending into the housing 11 can be stacked with the first tab 121 and the second tab 131 along the first direction X, The connection surface 144 of the electrode terminal 14 facing the first tab 121 or the second tab 131 is welded to the first tab 121 and the second tab 131 .

Furthermore, based on the implementation form that "the electrode terminal 14 includes a first section 141, a second section 142 and a third section 143", the first section 141 can be located between the stacked first tab 121 and the second tab 131 and the shell. 11, the first section 141, the first tab 121 and the second tab 131 are stacked and welded to each other.

At least part of the first tab 121 of the first electrode assembly and at least part of the second tab 131 of the second electrode assembly 13 are located between the protrusion 114 and the second wall 112 . At the same time, the positions of the electrode terminal 14 and the recess 113 are Correspondingly, at least part of the electrode terminal 14 , at least part of the first tab 121 and at least part of the second tab 131 share the space between the protrusion 114 and the second wall 112 of the housing 11 along the second direction Y. , thereby reducing the occupation of the internal space of the housing 11 by the first tab 121, the second tab 131 and the electrode terminal 14, which is conducive to increasing the space occupancy rate of the main body of the electrode assembly, thereby further increasing the energy density of the battery cell 10.

According to some embodiments of the present application, the first wall 111 and the second wall 112 are the walls with the largest area of the battery cell 10 .

Specifically, the electrode terminal 14 is provided on the large surface of the battery cell 10 . Compared with the structure in which the electrode terminals 14 are arranged on the narrow surface of the battery cell 10, the size requirements of the recess 113 and the electrode terminal 14 can be effectively ensured, and it is ensured that after the battery cells 10 are stacked, the recess 113 can accommodate the battery cell where it is located. The electrode terminals 14 of 10 or the electrode terminals 14 of the adjacent battery cells 10 ensure the energy density of the battery 100 .

According to some embodiments of the present application, please refer to Figure 3 again. The housing 11 includes a third wall 118. The thickness direction of the third wall 118, the first direction X and the second direction Y are two by two vertical, and the third wall 118 is provided with a Injection holes 17 for injecting electrolyte into the battery cells 10 .

Specifically, the thickness direction of the third wall 118 extends along the third direction Z, and the first wall 111 and the second wall 112 are arranged oppositely along the first direction X, then the two ends of the third wall 118 along the first direction X can be Connected to the first wall 111 and the second wall 112 respectively. At the same time, the thickness direction of the third wall 118 is perpendicular to the arrangement direction of the first electrode assembly 12 and the second electrode assembly 13 (second direction Y).

The liquid injection hole 17 is used to inject electrolyte into the battery cell 10. The liquid injection hole 17 is provided on the third wall 118. Along the third direction Z, the projection of the liquid injection hole 17 can fall into the first cavity 115 or into the first cavity 115. It can enter the second cavity 116 or fall between the first cavity 115 and the second cavity 116 . For example, the projection of the liquid injection hole 17 may fall between the first cavity 115 and the second cavity 116 .

It can be understood that only one liquid injection hole 17 may be provided, or multiple liquid injection holes 17 may be provided.

The housing 11 may include two third walls 118 oppositely arranged along the third direction Z. When multiple liquid injection holes 17 are provided, the plurality of liquid injection holes 17 may all be provided at intervals on the same third wall 118. Of course, The plurality of liquid injection holes 17 may also be provided in two third walls 118 .

The first electrode assembly and the second electrode assembly 13 are arranged along the second direction Y. The thickness direction of the third wall 118 is perpendicular to the second direction Y. The liquid injection hole 17 is provided on the third wall 118, which is beneficial to reducing and balancing the electrolysis. The infiltration distance of the liquid into the first electrode assembly 12 and the second electrode assembly 13 increases the infiltration speed of the electrolyte into the first electrode assembly 12 and the second electrode assembly 13 .

According to some embodiments of the present application, as shown in FIGS. 3 and 4 , along the thickness direction of the third wall 118 , at least part of the projection of the liquid injection hole 17 falls between the convex portion 114 and the second wall 112 .

Specifically, the thickness direction of the third wall 118 extends along the third direction Z, and along the third direction Z, a portion of the liquid injection hole 17 is projected to fall between the convex portion 114 and the second wall 112 , or, along the third direction Z, Z, the projection of the liquid injection hole 17 completely falls into the convex portion 114 and the second wall 112 .

A protrusion 114 is provided at a position corresponding to the recess 113. The protrusion 114 divides the internal space of the housing 11 into a first cavity 115 and a second cavity 116 arranged along the second direction Y. The first electrode assembly 12 and the second electrode assembly are 13 is provided in the first cavity 115 and the second cavity 116, and at least part of the projection of the liquid injection hole 17 falls between the convex portion 114 and the second wall 112, then at least part of the liquid injection hole 17 corresponds to the first electrode assembly 12 and the second wall 112. The middle position of the second electrode assembly 13 enables the electrolyte to infiltrate into the first electrode assembly 12 and the second electrode assembly 13 from the middle of the first electrode assembly 12 and the second electrode assembly 13, and the liquid is injected here so that the electrolyte can be injected into the first electrode assembly 12 and the second electrode assembly 13. The bottom of hole 17 is not blocked by the electrode assembly, which greatly increases the injection speed and further improves the electrolyte injection efficiency.

According to some embodiments of the present application, please continue to refer to FIG. 3 , the housing 11 further includes two fourth walls 119 arranged oppositely along the second direction Y, the battery cell 10 also includes a pressure relief mechanism 18 , and the pressure relief mechanism 18 is provided On the fourth wall 119.

The pressure relief mechanism 18 is an element or component that releases the internal pressure or temperature of the battery cell 10 . The pressure relief mechanism 18 may take the form of an explosion-proof valve, an air valve, a pressure relief valve, a safety valve, a notch provided on the housing 11, etc. And pressure-sensitive or temperature-sensitive components or structures may be specifically used, that is, when the internal pressure or temperature of the battery cell 10 reaches a threshold, the pressure relief machine performs an action or the weak structure provided in the pressure relief mechanism 18 is destroyed, thereby A pressure relief channel is formed for releasing the internal pressure or temperature of the battery cell 10 . The actions performed by the pressure relief mechanism 18 may include, but are not limited to: at least a part of the pressure relief mechanism 18 ruptures, shatters, is torn or opened, etc.

It can be understood that only one pressure relief mechanism 18 may be provided, or multiple pressure relief mechanisms 18 may be provided. The housing 11 includes two fourth walls 119 oppositely arranged along the second direction Y. When multiple pressure relief mechanisms 18 are provided, the multiple pressure relief mechanisms 18 can all be spaced apart on the same fourth wall 119 . Of course, multiple pressure relief mechanisms 18 can be spaced apart from each other. The two pressure relief mechanisms 18 can also be separately provided on the two fourth walls 119 . For example, two pressure relief mechanisms 18 are provided, one pressure relief mechanism 18 is provided on each fourth wall 119 .

The electrode terminal 14 is disposed on the first wall 111 or the second wall 112 opposite along the first direction X, and the pressure relief mechanism 18 is disposed on the fourth wall 119 opposite along the second direction Y. When the battery cell 10 undergoes thermal runaway, The high-temperature and high-pressure gas in the battery cell 10 flows toward the pressure relief mechanism 18 along the second direction Y and is discharged through the pressure relief mechanism 18. The electrode terminals 14 and the pressure relief mechanism 18 are arranged on different walls of the battery cell 10, which can effectively reduce the pressure of the electrodes. There is a risk that the terminal 14 may be blown due to the high temperature flame of the battery cell 10 .

Please refer to Figures 3 to 20, and further refer to Figures 21 to 23. Figure 21 is a schematic diagram of the battery unit arrangement structure of the battery provided by some embodiments of the present application; Figure 22 is a schematic diagram of the battery cell arrangement provided by some embodiments of the present application. A schematic diagram of the arrangement of battery cells from one perspective; Figure 23 is a schematic diagram of the arrangement of battery cells from a second perspective of a battery provided by some embodiments of the present application. Some embodiments of the present application also provide a battery 100, including at least one row of battery cells 10 as described in any of the above solutions. Each row of battery cells 10 includes multiple battery cells 10. Each row of battery cells 10 Two adjacent battery cells 10 in are arranged along the third direction Z and are electrically connected to each other. The third direction Z, the second direction Y and the first direction X are perpendicular to each other.

Each row of battery cells 10 includes at least two battery cells 10 . The battery cells 10 in each row are arranged along the third direction Z. The first electrode assembly 12 and the second electrode assembly 13 of each battery cell 10 are arranged along the second direction Z. Arrange in direction Y.

Two adjacent battery cells 10 in each row of battery cells 10 may be directly connected through the electrode terminals 14 , or may be indirectly connected through current-carrying components such as busbars (also known as busbars, busbars, and bars).

The battery 100 may include one row of battery cells 10 or multiple rows of battery cells 10 .

According to some embodiments of the present application, the electrode terminals 14 extend beyond the outline of the housing 11 along the third direction Z, and the electrode terminals 14 of two adjacent battery cells 10 are welded.

Specifically, each row of battery cells 10 includes at least two battery cells 10 . The battery cells 10 in each row are arranged along the third direction Z. The electrode terminals 14 extend beyond the outline of the housing 11 along the third direction Z. Two adjacent battery cells 10 are arranged in the third direction Z. The electrode terminals 14 of each battery cell 10 are welded.

As shown in FIGS. 21 and 22 , the electrode terminal 14 may include a first electrode terminal 14 a and a second electrode terminal 14 b with opposite polarities. The first electrode terminal 14 a and the second electrode terminal 14 b are spaced apart along the third direction Z, and Extending backward in the third direction Z and beyond the outline of the housing 11, the first electrode terminal 14a of the battery cell 10 can be welded to the second electrode terminal 14b of the adjacent battery cell 10, and so on, so that within the same row, The battery cells 10 are connected in series with each other.

The electrode terminals 14 extend beyond the outline of the housing 11 along the third direction Z in which the battery cells 10 are arranged. The electrode terminals 14 of two adjacent battery cells 10 along the third direction Z are directly welded to each other, so that the plurality of battery cells 10 are mutually welded. Electrical connection can effectively save the use of bus components, which is helpful to further increase the energy density of the battery 100.

According to some embodiments of the present application, the battery 100 includes multiple rows of battery cells 10 stacked along the first direction X.

For example, as shown in FIGS. 21 and 22 , the battery 100 includes two rows of battery cells 10 , and the two rows of battery cells 10 are stacked along the first direction X. The first wall 111 of a single row of battery cells 10 is opposite to the second wall 112 of an adjacent row of battery cells 10 .

In practical applications, the first direction X may extend along the vertical direction, that is, the multiple rows of battery cells 10 of the battery 100 are stacked in the vertical direction. In order to accommodate the electrode terminal 14 in the recess 113 as much as possible, the space occupation rate of the electrode terminal 14 is reduced, and the energy density of the battery 100 is increased.

Moreover, the electrode assembly will inevitably expand along the thickness direction of the pole piece during the charging and discharging process (in the electrode assembly of the rolled structure, the expansion force is the largest in the direction perpendicular to the flat surface; in the electrode assembly of the laminated structure In the assembly, the expansion force is greatest along the stacking direction of the first pole piece and the second pole piece). In the prior art, the direction in which the electrode assembly of the battery cell 10 exerts the maximum expansion force on the housing 11 is always in the horizontal direction. Since the size of the battery 100 in the horizontal direction is much larger than the size in the vertical direction (for example, due to the height limit of the chassis of the vehicle 1000 , more battery cells 10 need to be stacked in the horizontal direction, and the accumulation of expansion force is large. ), therefore, the existing battery 100 is subject to a very large expansion force in the horizontal direction, and very thick end plates need to be installed on both sides of the battery 100 in the horizontal direction to resist the expansion force, and thickening the end plates will reduce the energy of the battery 100 density.

In this embodiment, based on the fact that "the first electrode assembly 12 has a laminated structure, and the pole pieces of the first electrode assembly 12 are stacked along the first direction X; or the first electrode assembly 12 has a wound structure, the first electrode assembly 12, the winding axis is perpendicular to the first direction The direction of the force is towards the vertical direction, and the number of battery cells stacked in the vertical direction is less than 10. Therefore, compared with the existing technology, the above solution can reduce the maximum expansion force of the battery 100, so a smaller end plate can be used, thereby increasing the energy density of the battery 100.

According to some embodiments of the present application, the present application also provides an electrical device, including the battery 100 described in any of the above solutions, and the battery 100 is used to provide electric energy.

It can be understood that the electrical device may be any of the aforementioned electrical devices.

Please refer to Figures 3 to 9. Some embodiments of the present application provide a battery cell 10. The battery cell 10 includes a housing 11, a first electrode assembly 12, a second electrode assembly 13, an electrode terminal 14, and a liquid injection hole. 17 and a pressure relief mechanism 18. The housing 11 includes a first wall 111 and a second wall 112 oppositely arranged along the first direction X, two third walls 118 oppositely arranged along the third direction Z and two oppositely arranged third walls 118 along the second direction Y. The two fourth walls 119. The outer surface of the first wall 111 is provided with a recess 113. The two ends of the recess 113 along the third direction Z extend to both edges of the first wall 111 along the third direction Z. The inner surface of the first wall 111 is in contact with the recess 113. A protrusion 114 is provided at a corresponding position. The protrusion 114 divides the internal space of the housing 11 into a first cavity 115 and a second cavity 116 arranged along the second direction Y. The first electrode assembly 12 is accommodated in the first cavity 115. The second electrode assembly 13 is received in the second cavity 116 . Among them, the first wall 111 and the second wall 112 are the walls with the largest area of the housing 11 , and the third direction Z, the second direction Y and the first direction X are perpendicular to each other.

Both the first electrode assembly 12 and the second electrode assembly 13 have a laminated structure, and the pole pieces of the first electrode assembly 12 and the pole pieces of the first electrode assembly 12 are stacked along the first direction X.

The first electrode assembly 12 includes a first tab 121 , and the second electrode assembly 13 includes a second tab 131 . The first tab 121 and the second tab 131 have the same polarity and are arranged opposite to each other. At least part of the first tab 121 At least part of the second pole tab 131 is located between the protrusion 114 and the second wall 112 , and the first pole tab 121 and the second pole tab 131 are stacked along the first direction X.

The bottom wall of the recess 113 is provided with an electrode lead-out hole 117. The electrode terminal 14 has a sheet-like structure and includes a first section 141, a second section 142 and a third section 143 connected in sequence. The first section 141 is located in the housing 11, and the third section 143 is connected in sequence. The section 143 is located outside the housing 11 , and the second section 142 is inserted through the electrode lead-out hole 117 and connects the first section 141 and the third section 143 . The first section 141 and the third section 143 extend in opposite directions from the second section 142. The side surface of the first section 141 away from the first wall 111 is welded to the first tab 121 and the second tab 131. The third section 143 extends along the third direction Z and beyond the outline of the housing 11 .

Please refer to Figure 21. Some embodiments of the present application provide a battery 100, including two rows of battery cells 10 provided in the above embodiments. Each row of battery cells 10 includes 4 battery cells 10. Each row of battery cells 10 Two adjacent battery cells 10 are arranged along the third direction Z, and the electrode terminals 14 of the two adjacent battery cells 10 are welded. Two rows of battery cells 10 are stacked in a vertical direction extending along the first direction X. The third section 143 of the electrode terminal 14 of each row of battery cells 10 is received in the recess 113 of the row of battery cells 10 .

Please refer to Figures 10 to 16. Some embodiments of the present application provide a battery cell 10. The battery cell 10 includes a housing 11, a first electrode assembly 12, a second electrode assembly 13, an electrode terminal 14, and a liquid injection hole. 17 and a pressure relief mechanism 18. The housing 11 includes a first wall 111 and a second wall 112 oppositely arranged along the first direction X, two third walls 118 oppositely arranged along the third direction Z and two oppositely arranged third walls 118 along the second direction Y. The two fourth walls 119. The outer surface of the first wall 111 is provided with a recess 113. The two ends of the recess 113 along the third direction Z extend to both edges of the first wall 111 along the third direction Z. The inner surface of the first wall 111 is in contact with the recess 113. A protrusion 114 is provided at a corresponding position. The protrusion 114 divides the internal space of the housing 11 into a first cavity 115 and a second cavity 116 arranged along the second direction Y. The first electrode assembly 12 is accommodated in the first cavity 115. The second electrode assembly 13 is received in the second cavity 116 . The first wall 111 and the second wall 112 are the walls with the largest area of the housing 11 , and the third direction Z, the second direction Y and the first direction X are perpendicular to each other.

The second wall 112 is provided with an electrode lead-out hole 117. The electrode terminal 14 has a sheet-like structure and includes a first section 141, a second section 142 and a third section 143 connected in sequence. The first section 141 is located in the housing 11, and the third section 143 is connected in sequence. 143 is located outside the housing 11, and the second section 142 passes through the electrode lead-out hole 117 and connects the first section 141 and the third section 143. The first section 141 and the third section 143 extend in opposite directions from the second section 142. The side surface of the first section 141 away from the second wall 112 is welded to the first tab 121 and the second tab 131. The third section 143 extends along the third direction Z and exceeds the outline of the housing 11 , and the electrode terminals 14 and the recess 113 are arranged correspondingly.

Referring to Figures 22 and 23, an embodiment of the present application provides a battery 100, including two rows of battery cells 10 provided in the above embodiment. Each row of battery cells 10 includes four battery cells 10. Each row of battery cells 10 Two adjacent battery cells 10 in the body 10 are arranged along the third direction Z, and the electrode terminals 14 of the two adjacent battery cells 10 are welded. Two rows of battery cells 10 are stacked in a vertical direction extending along the first direction X. The third section 143 of the electrode terminal 14 of the first row of battery cells 10 is received in the recess 113 of the second row of battery cells 10 .

It should be noted that, as long as there is no conflict, the features in the embodiments of this application can be combined with each other.

While the present application has been described with reference to preferred embodiments, various modifications may be made and equivalents may be substituted for components thereof without departing from the scope of the application. In particular, as long as there is no structural conflict, the technical features mentioned in the various embodiments can be combined in any way. The application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

A battery cell including:

The shell includes a first wall and a second wall oppositely arranged along a first direction. The outer surface of the first wall is provided with a recess, and the inner surface of the first wall is provided with a convex portion at a position corresponding to the recess. , the convex portion divides the internal space of the housing into a first cavity and a second cavity arranged along a second direction, the second direction being perpendicular to the first direction;

a first electrode assembly accommodated in the first cavity;

a second electrode assembly accommodated in the second cavity;

An electrode terminal is provided on the first wall or the second wall, and the electrode terminal is connected to the first electrode assembly and the second electrode assembly;

Wherein, along the first direction, the electrode terminal is arranged corresponding to the recess.
The battery cell according to claim 1, wherein the first electrode assembly has a laminated structure, and the pole pieces of the first electrode assembly are stacked along the first direction; or

The first electrode assembly has a wound structure, and the winding axis of the first electrode assembly is perpendicular to the first direction.
The battery cell according to claim 1 or 2, wherein the second electrode assembly has a laminated structure, and the pole pieces of the second electrode assembly are stacked along the first direction; or

The second electrode assembly has a wound structure, and the winding axis of the second electrode assembly is perpendicular to the first direction.
The battery cell according to any one of claims 1 to 3, wherein the electrode terminal has a sheet structure.
The battery cell according to claim 4, wherein the thickness of the electrode terminal is T1, 0.6mm≤T1≤2.5mm, preferably, 0.8mm≤T1≤2mm.
The battery cell according to any one of claims 1 to 5, wherein the first wall or the second wall is provided with an electrode lead-out hole, and the electrode terminal is inserted through the electrode lead-out hole.
The battery cell according to claim 6, wherein the electrode terminal includes a first section, a second section and a third section, the first section is located in the housing and connected to the electrode assembly, and the The third section is located outside the housing, and the second section penetrates the electrode lead-out hole and connects the first section and the third section.
The battery cell of claim 7, wherein the first section and the third section extend in the same direction from the second section; or

The first section and the third section extend in opposite directions from the second section.
The battery cell according to claim 7 or 8, wherein the second section includes a fuse portion.
The battery cell according to any one of claims 1 to 9, wherein along the first direction, the height of the electrode terminal protruding from the outer surface of the housing is D1, and the depth of the recess is H1 , D1/H1≤0.5, preferably, 0.1≤D1/H1≤0.5.
The battery cell according to any one of claims 1 to 10, wherein, along the third direction, the portion of the electrode terminal located outside the battery cell exceeds the housing, and the third direction, the second The directions are perpendicular to the first direction.
The battery cell according to claim 11, wherein the recess extends along the third direction, and both ends of the recess in the third direction respectively extend to both ends of the housing in the third direction. Side edges.
The battery cell according to claim 11 or 12, wherein the dimension of the electrode terminal beyond the housing is D2, 2cm≤D2≤5cm, preferably, 3cm≤D2≤5cm.
The battery cell according to any one of claims 1 to 13, wherein along the second direction, the width of the recess is W1 and the length of the first wall is L, satisfying 0.1≤W1/L ≤0.5.
The battery cell according to any one of claims 1 to 14, wherein along the second direction, the width of the electrode terminal is W2, the width of the recess is W1, and W2/W1≤0.9, preferably Ground, 0.7≤W2/W1≤0.9.
The battery cell according to any one of claims 1 to 15, wherein along the first direction, the depth of the recess is H1, and the thickness of the outer shell is T2, 0.1≤H1/T2≤0.5, Preferably, 0.3≤H1/T2≤0.5.
The battery cell according to any one of claims 1-16, wherein the battery cell further includes:

An insulating member is used to insulate and isolate the electrode terminal and the housing.
The battery cell according to any one of claims 1 to 17, wherein the electrode terminal is provided on the first wall, and the electrode terminal is at least partially accommodated in the recess.
The battery cell according to claim 18, wherein the first electrode assembly includes a first tab, the second electrode assembly includes a second tab, the first tab and the second tab The tabs have the same polarity, and the electrode terminal is connected to the first tab and the second tab. The battery cell also includes:

An insulating layer is provided on the inner surface of the first wall at a position corresponding to the recess. The insulating layer is used to insulate and isolate the first wall and the first tab and to insulate and isolate the first wall. and the second tab.
The battery cell according to any one of claims 1 to 17, wherein the electrode terminal is provided on the second wall, the first electrode assembly includes a first tab, and the second electrode The assembly includes a second tab, the first tab and the second tab have the same polarity, the electrode terminal is connected to the first tab and the second tab, and the battery cell also include:

An insulating layer is provided on the inner surface of the second wall. The projection of the insulating layer on the first wall at least partially falls into the recess. The insulating layer is used to insulate and isolate the second wall and the second wall. The first tab and insulation isolate the second wall from the second tab.
The battery cell according to claim 19 or 20, wherein at least part of the first tab of the first electrode assembly and at least part of the second tab of the second electrode assembly are located on the protrusion. between the bottom and the second wall.
The battery cell according to any one of claims 1 to 21, wherein the first wall and the second wall are walls with the largest area of the battery cell.
The battery cell according to any one of claims 1 to 22, wherein the outer casing includes a third wall, and the thickness direction of the third wall, the first direction and the second direction are perpendicular to each other. , the third wall is provided with an injection hole for injecting electrolyte into the interior of the battery cell.
The battery cell according to claim 23, wherein at least part of the projection of the liquid injection hole falls between the convex portion and the second wall along the thickness direction of the third wall.
The battery cell according to any one of claims 1 to 24, wherein the housing further includes two fourth walls oppositely arranged along the second direction, and the battery cell further includes:

A pressure relief mechanism is provided on the fourth wall.
A battery, comprising at least one row of battery cells according to any one of claims 1 to 25, each row of battery cells including a plurality of said battery cells, each row of said battery cells Two adjacent battery cells are arranged along a third direction and are electrically connected to each other, and the third direction, the second direction and the first direction are perpendicular to each other.
The battery according to claim 26, wherein the electrode terminal exceeds the outline of the housing along the third direction, and the electrode terminals of two adjacent battery cells are welded.
The battery according to claim 26 or 27, wherein the battery includes a plurality of rows of battery cells stacked along the first direction.
An electrical device, which includes the battery according to any one of claims 26 to 28, wherein the battery is used to provide electrical energy.