Battery monomer, electric connector, battery device, power utilization device and energy storage device

Abstract

The utility model discloses a battery monomer, an electric connector, a battery device, a power utilization device and an energy storage device. The battery cell includes a case, an electrode assembly, an electrode terminal, and an electrical connector. The electrode assembly is located in the containing cavity of the shell and comprises an electrode body and a tab connected with the electrode body, and the thickness direction of the electrode body is the first direction. The electrode terminal passes through a mounting hole formed in a first wall of the housing. The electric connecting piece comprises a tab connecting part, an electrode terminal connecting part and a middle connecting part, the tab connecting part is connected with the tab, the electrode terminal connecting part is connected with the electrode terminal, the middle connecting part is connected with the tab connecting part and the electrode terminal connecting part, and the tab connecting part and the electrode terminal connecting part are located on the two opposite sides of the middle connecting part in the second direction. Wherein at least one side of the tab connecting part along the first direction is provided with an accommodating space, and at least part of the tab is accommodated in the accommodating space. The battery cell provided by the embodiment of the utility model is high in energy density.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and in particular to battery cells, electrical connectors, battery devices, electrical devices, and energy storage devices. Background Art

[0002] New energy batteries are being used more and more widely in life and industry. For example, new energy vehicles equipped with battery devices have been widely used. In addition, battery devices are also increasingly being used in energy storage fields.

[0003] With the continuous development of battery technology, how to improve the energy density of battery cells is one of the research topics in the industry. Utility Model Content

[0004] In order to solve the above technical problems, the present application provides a battery cell, an electrical connector, a battery device, an electrical device and an energy storage device with high energy density.

[0005] This application is implemented through the following technical solutions.

[0006] The first aspect of the present application provides a battery cell, which includes a shell with a accommodating cavity formed therein, the shell including a first wall, the first wall being formed with a mounting hole; an electrode assembly located in the accommodating cavity, the electrode assembly including an electrode body and a tab connected to the electrode body, the thickness direction of the electrode body being a first direction; an electrode terminal passing through the mounting hole; and an electrical connector including a tab connection portion, an electrode terminal connection portion and an intermediate connection portion, the tab connection portion connecting the tab, the electrode terminal connection portion connecting the electrode terminal, the intermediate connection portion connecting the tab connection portion and the electrode terminal connection portion, the tab connection portion and the electrode terminal connection portion being located on opposite sides of the intermediate connection portion along a second direction, the second direction being perpendicular to the first direction; wherein the tab connection portion has a accommodating space on at least one side along the first direction, and at least part of the tab is accommodated in the accommodating space.

[0007] Since the tab connection portion of the electrical connector has an accommodation space on at least one side along the first direction, and at least part of the tab is accommodated in the accommodation space, the accommodation space of the electrical connector along the side of the first direction can be fully utilized, reducing the space occupied by the tab in the height direction (third direction), so that the tab is not located as a whole below the electrical connector, which is beneficial to improving the space utilization rate in the shell of the battery cell and reserving more space for the electrode body. As a result, the volume of the electrode body can be appropriately increased without changing the shell size of the battery cell, thereby improving the energy density of the battery cell.

[0008] In some embodiments, the tab connection portion includes a first surface and a second surface opposite to each other along a third direction, the first surface faces the first wall, and the second surface faces away from the first wall; the tab includes a welding portion and a bending portion, the welding portion is connected to the bending portion, the welding portion is welded to the second surface of the tab connection portion, the bending portion protrudes relative to the welding portion along the third direction toward the side where the first wall is located, and the bending portion is accommodated in the accommodating space; the third direction is perpendicular to both the first direction and the second direction.

[0009] Thus, by changing the bending method of the tab, the tab structure can be made more compact and the overall size along the third direction can be smaller, thereby reducing the space occupied by the tab, saving space within the housing cavity, and thus increasing the space within the cavity for accommodating the electrode body, which is beneficial to improving the energy density of the battery cell. In addition, the bent portion of the tab is accommodated within the accommodating space, which can fully utilize the space on the side of the tab connection portion, further saving space within the housing cavity, and further beneficial to improving the energy density of the battery cell.

[0010] In some embodiments, along the third direction, the difference between the first dimension and the second dimension is greater than or equal to 0 mm and less than or equal to 3 mm, wherein the first dimension is the distance between the top surface of the bending portion and the first wall, and the second dimension is the distance between the first surface of the tab connecting portion and the first wall.

[0011] Therefore, along the third direction, the top surface of the bent portion is flush with the first surface of the pole tab connecting portion, or slightly higher than the first surface of the pole tab connecting portion. In this way, the area of the accommodating space along the height direction can be fully utilized to accommodate more pole tabs, thereby providing a larger space for the electrode body and increasing the energy density of the battery cell.

[0012] In some embodiments, at least a portion of the tab connecting portion is recessed along the first direction to form a groove portion, and the groove portion defines at least a portion of the accommodation space.

[0013] Thus, the groove formed by the tab connecting portion can constitute at least a portion of the accommodating space for accommodating the bent portion of the tab, thereby increasing the energy density of the battery cell without changing the shell size of the battery cell.

[0014] In some embodiments, the battery cell further includes an insulating member, which is located on the side of the first wall facing the electrode assembly; along the first direction, the width of the bent portion is smaller than the distance between the bottom wall of the groove portion and the outer edge of the insulating member.

[0015] In this way, the bent portion of the tab can be accommodated in the accommodation space while ensuring a good appearance of the tab, thereby saving the space occupied by the tab in the accommodation cavity along the third direction.

[0016] In some embodiments, along the first direction, the distance between the bottom wall of the groove portion and the outer edge of the insulating member is greater than or equal to a third dimension; wherein the third dimension is the sum of the distance between the shell and the insulating member along the first direction and half of the width of the tab connecting portion along the first direction.

[0017] As a result, the accommodating space can have enough space to accommodate the bent portion of the tab.

[0018] In some embodiments, the distance between the bottom wall of the groove portion and the outer edge of the insulating member is less than or equal to a fourth dimension; wherein the fourth dimension is half of the thickness of the battery cell along the first direction minus the third dimension.

[0019] Therefore, the tab connection portion can meet the overcurrent requirement of the tab connection portion and the requirement of welding with the welding portion of the tab while forming the groove portion.

[0020] In some embodiments, along the first direction, the width of the groove portion is less than or equal to half the width of the electrical connector.

[0021] As a result, the tabs can be well welded to the tab connecting parts without being excessively stretched, thereby reducing the possibility of tab redundancy and effectively reducing production costs.

[0022] In some embodiments, along the first direction, the width of the groove portion is greater than or equal to a fifth dimension; wherein the fifth dimension is the distance between the bottom of the groove portion and the shell along the first direction minus the distance between the electrical connector and the shell along the first direction.

[0023] Thus, at least one side of the tab connection portion along the first direction has enough space to form an accommodating space for the bent portion of the tab, thereby facilitating improvement of the energy density of the battery cell.

[0024] In some embodiments, along the second direction, the length of the groove portion is less than or equal to the length of the electrical connector, and greater than or equal to the length of the tab plus an error dimension.

[0025] As a result, the groove portion can better accommodate the bent portion of the tab along the length direction, reducing the possibility of interference between the groove sidewall and the bent portion, thereby improving the reliability of the battery cell.

[0026] In some embodiments, the electrode terminal connection portion and the tab connection portion extend along the second direction, the intermediate connection portion extends along a third direction, and the tab connection portion is closer to the first wall than the motor terminal connection portion in the third direction; the third direction is perpendicular to both the first direction and the second direction.

[0027] In this way, the space on the side of the first wall facing the accommodating cavity can be fully utilized, the size of the tab along the third direction can be further saved, more space can be reserved for the electrode body, and the energy density of the battery cell can be improved.

[0028] In some embodiments, the number of the groove portions is two, and the two groove portions are located on opposite sides of the tab connecting portion along the first direction; and the shapes and sizes of the two groove portions are the same or different.

[0029] Therefore, the shape and size of the groove portion can be set according to the actual lead-out shape and size of the tab, thereby adapting to different tab forms.

[0030] In some embodiments, the tab connection portion is flat; and / or the electrode terminal connection portion is flat.

[0031] This makes it easier for the electrode terminal and the tab to be connected to the electrode terminal connecting portion and the tab connecting portion, respectively, thereby improving the reliability of the electrical connector.

[0032] In some embodiments, the electrode terminal includes a positive terminal and a negative terminal; the electrical connector includes a first electrical connector and a second electrical connector; the tab includes a positive tab and a negative tab, the positive tab is located on the same side as the positive terminal, and / or the negative tab is located on the same side as the negative terminal, the positive tab is connected to the positive terminal through the first electrical connector, and the negative tab is connected to the negative terminal through the second electrical connector.

[0033] Thus, at least part of the positive electrode tab can be accommodated in the accommodation space provided on at least one side of the first electrical connector along the first direction, and at least part of the negative electrode tab can be accommodated in the accommodation space provided on at least one side of the second electrical connector along the first direction, thereby reducing the size of the positive electrode tab and the negative electrode tab along the third direction, reserving more space for the electrode body in the accommodation cavity, which is beneficial to improving the energy density of the battery cell.

[0034] In addition, since the positive electrode tab and the positive terminal are located at the same end, and / or the negative electrode tab and the negative terminal are located at the same end, it is easier to connect the tabs and the electrode terminals, and can save space in the battery cell shell, which is beneficial to improving the energy density of the battery cell.

[0035] In some embodiments, the electrode terminal includes a positive terminal and a negative terminal; the electrical connector includes a first electrical connector and a second electrical connector; the tab includes a positive tab and a negative tab, the positive tab and the positive terminal are located on different sides, and / or the negative tab and the negative terminal are located on different sides, the positive tab is connected to the positive terminal through the first electrical connector, and the negative tab is connected to the negative terminal through the second electrical connector.

[0036] Thus, at least part of the positive electrode tab can be accommodated in the accommodation space provided on at least one side of the first electrical connector along the first direction, and at least part of the negative electrode tab can be accommodated in the accommodation space provided on at least one side of the second electrical connector along the first direction, thereby reducing the size of the positive electrode tab and the negative electrode tab along the third direction, reserving more space for the electrode body in the accommodation cavity, which is beneficial to improving the energy density of the battery cell.

[0037] In addition, since the positive electrode tab and the positive terminal are located on different sides, and / or the negative electrode tab and the negative terminal are located on different sides, this helps to improve the flexibility of connecting the tab and the electrode terminal, and when multiple battery cells are grouped, it helps to improve the connection flexibility between battery cells.

[0038] In some embodiments, there are multiple electrode assemblies, and the multiple electrode assemblies are arranged in parallel along the first direction. The electrode tabs with the same polarity of the multiple electrode assemblies are connected through the same electrical connector.

[0039] This can reduce the number of assembly steps, lower the difficulty of assembly, and help reduce production costs.

[0040] The second aspect of the present application provides an electrical connector for a battery cell, wherein the thickness direction of the battery cell is a first direction, and the electrical connector includes: a pole tab connection portion for connecting to the pole tab of the battery cell; an electrode terminal connection portion for connecting to the electrode terminal of the battery cell; and an intermediate connection portion for connecting the pole tab connection portion and the electrode terminal connection portion, wherein the pole tab connection portion and the electrode terminal connection portion are located on opposite sides of the intermediate connection portion along a second direction, and the second direction is perpendicular to the first direction; wherein the pole tab connection portion has an accommodating space on at least one side along the first direction, and the accommodating space is used to accommodate at least part of the pole tab.

[0041] Since the tab connection portion of the electrical connector has an accommodation space on at least one side along the first direction, and the accommodation space can accommodate at least part of the tab, the accommodation space of the electrical connector along the side of the first direction can be fully utilized, reducing the space occupied by the tab in the height direction (third direction) so that it is not located as a whole below the electrical connector, which is beneficial to improving the space utilization rate in the shell of the battery cell and reserving more space for the electrode body. Furthermore, the volume of the electrode body can be appropriately increased without changing the shell size of the battery cell, thereby increasing the energy density of the battery cell and improving the energy density of the battery.

[0042] A third aspect of the present application provides a battery device, comprising: a box; and at least one battery cell as described in the first aspect of the present application, wherein the battery cell is accommodated in the box.

[0043] The battery device provided in the present application includes the battery cell provided in the first aspect above, and therefore can reduce the space occupied by the tab along the third direction, thereby increasing the space occupied by the electrode body, which is beneficial to improving the energy density of the battery cell.

[0044] A fourth aspect of the present application provides an electrical device, which includes the battery cell described in the first aspect of the present application or the battery device described in the third aspect of the present application for providing electrical energy.

[0045] The electrical device of the embodiment of the present application includes the battery cell provided by the first aspect or the battery device provided by the third aspect. Therefore, the space occupied by the tab of the battery cell along the third direction can be reduced, and the space occupied by the electrode body can be increased, which is beneficial to improving the energy density of the battery cell, thereby improving the energy density of the battery device, thereby extending the power supply time of the battery cell or the battery device to the electrical device.

[0046] The fifth aspect of the present application provides an energy storage device, which includes the battery cell described in the first aspect of the present application or the battery device described in the third aspect of the present application for providing electrical energy.

[0047] The energy storage device of the embodiment of the present application includes the battery cell provided by the first aspect or the battery device provided by the third aspect. Therefore, the space occupied by the tab of the battery cell along the third direction can be reduced, thereby increasing the space occupied by the electrode body, which is beneficial to improving the energy density of the battery cell, thereby increasing the energy density of the battery device, and thus extending the power supply time of the battery cell or battery device to the energy storage device.

[0048] Utility model effect

[0049] Through the present application, the space occupied by the electrode body of the electrode assembly in the accommodating cavity of the shell can be increased, thereby effectively improving the energy density of the battery cell. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] Various other advantages and benefits will become apparent to those skilled in the art upon reading the detailed description of the preferred embodiment below. The accompanying drawings are for illustration purposes only and are not to be considered as limiting the present application. The same reference numerals are used throughout the drawings to denote the same components. In the drawings:

[0051] Figure 1 A schematic structural diagram of a vehicle provided for some embodiments of the present application;

[0052] Figure 2 A schematic exploded perspective view of a battery device provided in some embodiments of the present application;

[0053] Figure 3 A schematic exploded perspective view of a battery cell provided in some embodiments of the present application;

[0054] Figure 4 A schematic cross-sectional view of a battery cell provided for some embodiments of the present application;

[0055] Figure 5 for Figure 4 Enlarged view of the circled section A;

[0056] Figure 6 A schematic diagram of the three-dimensional structure of an electrical connector provided in some embodiments of the present application;

[0057] Figure 7 A schematic diagram of a planar structure of an electrical connector provided in some embodiments of the present application;

[0058] Figure 8 Another schematic planar structural diagram of an electrical connector provided in some embodiments of the present application;

[0059] Figure 9 A schematic diagram of the partial planar structure of the positive electrode sheet, negative electrode sheet and separator of the electrode body provided in some embodiments of the present application.

[0060] Description of Reference Numerals

[0061] 1-shell; 1a-accommodation cavity; 11-first wall; 12-sealing bag; 2-electrode assembly; 21-electrode body; 211-positive electrode sheet; 212-negative electrode sheet; 213-separator; 22-tab; 221-positive electrode tab; 222-negative electrode tab; 223-welding portion; 224-bending portion; 3-electrode terminal; 31-positive electrode terminal; 32-negative electrode terminal; 4-electrical connector; 41-tab connection portion; 411- First surface; 412-second surface; 413-groove portion; 4131-groove bottom wall; 42-electrode terminal connection portion; 43-intermediate connection portion; 44-first electrical connection member; 45-second electrical connection member; 5-insulating member; 10-accommodation space; 100-battery cell; 200-controller; 300-motor; 400-battery device; 401-casing; 401a-cover; 401b-bottom plate; 1000-vehicle. DETAILED DESCRIPTION

[0062] The following embodiments of the technical solution of the present application will be described in detail with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application and are therefore only examples and are not intended to limit the scope of protection of the present application.

[0063] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this application belongs; the terms used herein are for the purpose of describing specific embodiments only and are not intended to limit this application; the terms "including" and "having" and any variations thereof in this application are intended to cover non-exclusive inclusions.

[0064] In the description of the embodiments of this application, the technical terms "first," "second," "third," etc. are used only to distinguish different objects and should not be understood to indicate or imply relative importance or implicitly specify the quantity, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, the meaning of "plurality" is more than two, unless otherwise specifically defined.

[0065] References herein to "embodiments" mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0066] In the description of the embodiments of this application, the term "and / or" is simply a description of the association relationship between associated objects, indicating that three relationships can exist. For example, A and / or B can represent the following three situations: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this document generally indicates that the associated objects are in an "or" relationship.

[0067] In the description of the embodiments of the present application, the orientations or positional relationships indicated by technical terms such as "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", and "circumferential" are based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the embodiments of the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed, operated or used in a specific orientation. Therefore, they should not be understood as limitations on the embodiments of the present application.

[0068] In the description of the embodiments of the present application, unless otherwise expressly specified or limited, technical terms such as "installed," "connected," "connect," and "fixed" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integration; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; internal connections between two components or interactions between two components. Those skilled in the art can understand the specific meanings of the above terms in the embodiments of the present application based on specific circumstances.

[0069] In the description of the embodiments of the present application, unless otherwise clearly specified and limited, the technical term "contact" should be understood in a broad sense, and can be direct contact, contact through an intermediate medium layer, contact with essentially no interaction force between the two contacting parties, or contact with interaction force between the two contacting parties.

[0070] Below, this application is described in detail.

[0071] Currently, new energy batteries are increasingly being used in everyday life and industry. They are not only used in energy storage systems such as hydropower, thermal power, wind power, and solar power plants, but are also widely used in electric vehicles like electric bicycles, electric motorcycles, and electric cars, as well as in a variety of fields such as aerospace. As the application of power batteries continues to expand, market demand is also growing.

[0072] During the manufacturing process of battery cells, it is necessary to electrically connect the tabs of the electrode assembly in the battery cell to the electrode terminals provided on the shell through electrical connectors (e.g., adapters) so that current can be drawn from or introduced into the electrode assembly.

[0073] In the related art, the electrical connector is in the shape of a flat plate, the pole ear is located below the electrical connector as a whole, and the pole ear is generally connected to the electrical connector in a 90° bent state. Therefore, the pole ear occupies a large space along the height direction of the battery cell (the third direction), which is not conducive to the space utilization within the battery cell, so that the electrode body of the electrode assembly occupies a smaller space, and the volume of the electrode body is positively correlated with the energy density of the battery cell. Therefore, reducing the volume of the electrode body will affect the energy density of the battery cell.

[0074] In response to the problems existing in the above-mentioned related technologies, the present application proposes a battery cell, which includes a shell, an electrode assembly, an electrode terminal and an electrical connector. A accommodating cavity is formed inside the shell, and the shell includes a first wall, and the first wall is formed with a mounting hole. The electrode assembly is located in the accommodating cavity, and the electrode assembly includes an electrode body and a tab connected to the electrode body, and the thickness direction of the electrode body is the first direction. The electrode terminal is passed through the mounting hole. The electrical connector includes a tab connection part, an electrode terminal connection part and an intermediate connection part, the tab connection part connects the tabs, the electrode terminal connection part connects the electrode terminals, the intermediate connection part connects the tab connection part and the electrode terminal connection part, and the tab connection part and the electrode terminal connection part are located on opposite sides of the intermediate connection part along the second direction, and the second direction is perpendicular to the first direction. Wherein, the tab connection part has an accommodating space on at least one side along the first direction, and at least part of the tab is accommodated in the accommodating space.

[0075] Since the tab connection portion of the electrical connector has an accommodation space on at least one side along the first direction, and at least part of the tab is accommodated in the accommodation space, the accommodation space of the electrical connector along the side of the first direction can be fully utilized, reducing the space occupied by the tab in the height direction (third direction), so that the tab is not located as a whole below the electrical connector, which is beneficial to improving the space utilization rate in the shell of the battery cell and reserving more space for the electrode body. As a result, the volume of the electrode body can be appropriately increased without changing the shell size of the battery cell, thereby improving the energy density of the battery cell.

[0076] The battery cells provided in the embodiments of the present application can be used, but are not limited to, in energy storage power supply systems, electrical devices such as vehicles, ships or aircraft, as well as energy storage devices such as energy storage containers and energy storage cabinets.

[0077] The embodiments of the present application provide an electrical device including the above-mentioned battery cell for providing electrical energy, and the electrical device includes but is not limited to a mobile phone, a tablet, a laptop computer, an electric toy, an electric tool, a battery-powered vehicle, an electric car, a ship, a spacecraft, etc. The electric toy may include a fixed or mobile electric toy, such as a game console, an electric car toy, an electric ship toy, and an electric airplane toy, etc. The spacecraft may include an airplane, a rocket, a space shuttle, and a spacecraft, etc.

[0078] In the following embodiments, for the convenience of description, the electric device of one embodiment of the present application is taken as an example of a vehicle 1000. The following description is made with reference to the accompanying drawings.

[0079] Figure 1 The schematic diagram of the structure of the vehicle 1000 provided in some embodiments of the present application. The vehicle 1000 may be a fuel vehicle, a gas vehicle or a new energy vehicle. The new energy vehicle may be a pure electric vehicle, a hybrid vehicle or an extended range vehicle. Figure 1 As shown, battery cells 100 are installed inside vehicle 1000. Battery cells 100 can be located at the bottom, front, or rear of vehicle 1000. Battery cells 100 can be used to power vehicle 1000. For example, battery cells 100 can serve as an operating power source for vehicle 1000. Vehicle 1000 also includes a controller 200 and a motor 300. Controller 200 is used to control battery cells 100 to power motor 300, for example, to meet the power requirements of vehicle 1000 during startup, navigation, and driving.

[0080] In some embodiments of the present application, the battery cell 100 can not only serve as the operating power source of the vehicle 1000, but also serve as the driving power source of the vehicle 1000, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000.

[0081] Figure 2 This is a schematic diagram of a three-dimensional exploded view of a battery device 400 provided in an embodiment of the present application. Figure 2 As shown, the battery device 400 includes a box body 401 and at least one battery cell 100. The box body 401 includes a cover 401a and a bottom plate 401b. The cover 401a covers the bottom plate 401b, thereby forming a storage area for the battery cell 100 between the bottom plate 401b and the cover 401a.

[0082] In the battery device 400, there can be multiple battery cells 100, and the multiple battery cells 100 can be connected in series, in parallel, or in a mixed connection. Mixed connection means that the multiple battery cells 100 are both connected in series and in parallel. The multiple battery cells 100 can be directly connected in series, in parallel, or in a mixed connection, and then the whole composed of the multiple battery cells 100 is placed in the storage space formed by the bottom plate 401b and the cover 401a. Of course, the battery cells 100 can also be a battery module formed by first connecting multiple battery cells 100 in series, in parallel, or in a mixed connection, and then the multiple battery modules are connected in series, in parallel, or in a mixed connection to form a whole, and are accommodated in the storage space formed by the bottom plate 401b and the cover 401a. The battery device 400 can also include other structures. For example, the battery device 400 can also include a busbar component for realizing electrical connection between the multiple battery cells 100.

[0083] Below, refer to Figures 3 to 9 Some embodiments of the present application are described in detail.

[0084] Figure 3 A schematic exploded perspective view of a battery cell provided in some embodiments of the present application. Figure 4 Schematic cross-sectional view of a battery cell provided for some embodiments of the present application. Figure 5 for Figure 4 Enlarged view of the circled section A. Figure 6 A schematic diagram of the three-dimensional structure of an electrical connector provided in some embodiments of the present application. Figure 7 A schematic diagram of the planar structure of an electrical connector provided in some embodiments of the present application. Figure 8 Another planar structural schematic diagram of an electrical connector provided in some embodiments of the present application. Figure 9 A schematic diagram of the partial planar structure of the positive electrode sheet, negative electrode sheet and separator of the electrode body provided in some embodiments of the present application.

[0085] In some embodiments of the present application, for ease of description, a first direction, a second direction, and a third direction are set, and the first direction, the second direction, and the third direction are perpendicular to each other. However, those skilled in the art should understand that the embodiments of the present application are not limited to the case where the three directions are perpendicular to each other. Figures 3 to 9 As shown by the arrows in FIG, the direction of arrow X is the first direction, the direction of arrow Y is the second direction, and the direction of arrow Z is the third direction. The direction indicated by arrow Z along the third direction is sometimes referred to as "upward," and the opposite direction is referred to as "downward."

[0086] The first aspect of the present application provides a battery cell 100, which includes a shell 1, an electrode assembly 2, an electrode terminal 3 and an electrical connector 4. A housing 1a is formed inside the housing 1, and the housing 1 includes a first wall 11, and the first wall 11 is formed with a mounting hole. The electrode assembly 2 is located in the housing 1a, and the electrode assembly 2 includes an electrode body 21 and a tab 22 connected to the electrode body 21, and the thickness direction of the electrode body 21 is the first direction. The electrode terminal 3 is inserted into the mounting hole. The electrical connector 4 includes a tab connection portion 41, an electrode terminal connection portion 42 and an intermediate connection portion 43. The tab connection portion 41 is connected to the tab 22, the electrode terminal connection portion 42 is connected to the electrode terminal 3, and the intermediate connection portion 43 connects the tab connection portion 41 and the electrode terminal connection portion 42. The tab connection portion 41 and the electrode terminal connection portion 42 are located on opposite sides of the intermediate connection portion 43 along a second direction, and the second direction is perpendicular to the first direction. The tab connecting portion 41 has an accommodating space 10 on at least one side along the first direction, and at least a portion of the tab 22 is accommodated in the accommodating space 10 .

[0087] The battery cell 100 refers to a basic unit that can realize mutual conversion between chemical energy and electrical energy, and can be used to manufacture a battery device 400 to supply power to an electrical device or an energy storage device.

[0088] In the embodiment of the present application, the battery cell 100 is a secondary battery cell. A secondary battery cell refers to a battery cell that can be continuously used by activating active materials by charging after the battery cell is discharged.

[0089] The battery cell 100 can be a lithium-ion battery cell, a sodium-ion battery cell, a sodium-lithium-ion battery cell, a lithium metal battery cell, a sodium metal battery cell, a lithium-sulfur battery cell, a magnesium-ion battery cell, a nickel-hydrogen battery cell, a nickel-cadmium battery cell, a lead-acid battery cell, etc., and the embodiments of the present application are not limited to this.

[0090] In the embodiment of the present application, the battery cell 100 is a square-shell battery cell. In some other embodiments, the battery cell 100 may also be a battery cell of other shapes, which is not particularly limited in the present application.

[0091] like Figures 3 to 5 As shown, the battery cell 100 includes a housing 1, which is the outer protective shell of the battery cell 100 and defines a receiving cavity 1a therein for accommodating the electrode assembly 2 and electrolyte. The housing 1 may be made of steel, aluminum, plastic (e.g., polypropylene), composite metal (e.g., copper-aluminum composite), or aluminum-plastic film.

[0092] In some embodiments, the housing 1 can be a sealed structure or a non-sealed structure. For example, when the housing 1 is a sealed structure, it protects the electrode assembly 2 contained therein. A sealing bag 12 can also be included between the housing 1 and the electrode assembly 2. The sealing bag 12 is used to encapsulate the electrode assembly 2 and the electrolyte. Specifically, the sealing bag 12 can be a bag-shaped insulating member or an aluminum-plastic film.

[0093] The electrode assembly 2 is a component where electrochemical reactions occur in the battery cell 100, and the electrode assembly 2 includes an electrode body 21. Figure 9 As shown, the electrode body 21 includes a positive electrode sheet 211, a negative electrode sheet 212, and a separator 213. The positive electrode sheet 211, the negative electrode sheet 212, and the separator 213 are generally stacked along the thickness direction (first direction) of the battery cell. During the charge and discharge process of the battery cell 100, active ions (such as lithium ions) are embedded and released back and forth between the positive electrode sheet 211 and the negative electrode sheet 212. The separator 213 is arranged between the positive electrode sheet 211 and the negative electrode sheet 212 to prevent the positive and negative electrode sheets from short-circuiting while allowing active ions to pass through.

[0094] In some embodiments, the positive electrode sheet 211 may include a positive electrode current collector and a positive electrode active material disposed on at least one surface of the positive electrode current collector.

[0095] As an example, the positive electrode current collector has two surfaces facing each other in its thickness direction, and the positive electrode active material is provided on either or both of the two facing surfaces of the positive electrode current collector.

[0096] As an example, the positive electrode current collector may be a metal foil or a composite current collector. For example, as the metal foil, aluminum or stainless steel with a silver surface treatment, stainless steel, copper, nickel or titanium, etc. may be used. The composite current collector may include a polymer material base layer and a metal layer. The composite current collector may be formed by forming a metal material (aluminum, aluminum alloy, nickel, nickel alloy, titanium, titanium alloy, silver and silver alloy, etc.) on a polymer material substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0097] As an example, the positive electrode active material may include at least one of the following materials: lithium-containing phosphates, lithium transition metal oxides, and their respective modified compounds. However, the present application is not limited to these materials, and other traditional materials that can be used as positive electrode active materials for batteries may also be used. These positive electrode active materials may be used alone or in combination of two or more. Examples of lithium-containing phosphates may include, but are not limited to, at least one of lithium iron phosphate (such as LiFePO4 (also referred to as LFP)), a composite material of lithium iron phosphate and carbon, lithium manganese phosphate (such as LiMnPO4), a composite material of lithium manganese phosphate and carbon, lithium iron manganese phosphate, and a composite material of lithium iron manganese phosphate and carbon.

[0098] In some embodiments, the positive electrode sheet 211 may be made of metal foam. The metal foam may be nickel foam, copper foam, aluminum foam, or alloy foam. When the metal foam is used as the positive electrode, the surface of the metal foam may or may not be provided with a positive electrode active material. As an example, a lithium source material, potassium metal, or sodium metal may be filled and / or deposited within the metal foam, where the lithium source material is lithium metal and / or a lithium-rich material.

[0099] In some embodiments, the negative electrode sheet 212 may include a negative current collector.

[0100] As an example, the negative electrode current collector may be a metal foil, a metal foam, or a composite current collector. For example, as the metal foil, aluminum or stainless steel with a silver surface treatment, stainless steel, copper, nickel, carbon, or titanium, etc., may be used. The composite current collector may include a polymer material base layer and a metal layer. The metal foam may be nickel foam, copper foam, aluminum foam, or alloy foam, etc. The composite current collector may be formed by forming a metal material (copper, copper alloy, nickel, nickel alloy, titanium, titanium alloy, silver, and silver alloy, etc.) on a polymer material substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.). In some embodiments, the material of the positive electrode current collector may be aluminum, and the material of the negative electrode current collector may be copper.

[0101] In some embodiments, the separator 213 is a separator. The present application has no particular limitation on the type of separator, and any known separator with a porous structure having good chemical stability and mechanical stability can be selected.

[0102] As an example, the main material of the isolation membrane can be selected from at least one of glass fiber, non-woven fabric, polyethylene, polypropylene, polyvinylidene fluoride, and ceramics.

[0103] In some embodiments, separator 213 is a solid electrolyte.

[0104] In some embodiments, the electrode body 21 is a wound structure in which the positive electrode sheet and the negative electrode sheet are wound into a wound structure.

[0105] In some embodiments, the electrode body 21 is a laminated structure.

[0106] As an example, a plurality of positive electrode sheets 211 and a plurality of negative electrode sheets 212 may be provided, and the plurality of positive electrode sheets 211 and the plurality of negative electrode sheets 212 may be alternately stacked.

[0107] As an example, a plurality of positive electrode sheets 211 may be provided, and the negative electrode sheet 212 may be folded to form a plurality of stacked folded segments, with one positive electrode sheet 211 being sandwiched between adjacent folded segments.

[0108] As an example, the positive electrode sheet 211 and the negative electrode sheet 212 are both folded to form a plurality of stacked folded segments.

[0109] As an example, a plurality of separators 213 may be provided, each of which is disposed between any adjacent positive electrode sheets 211 or negative electrode sheets 212 .

[0110] As an example, the separator 213 may be provided continuously, and may be provided between any adjacent positive electrode sheets 211 or negative electrode sheets 212 by folding or winding.

[0111] In some embodiments, the battery cell 100 further includes an electrolyte, which acts as a conductor of ions between the positive and negative electrodes. This application does not specifically limit the type of electrolyte, and the electrolyte may be selected based on needs. The electrolyte may be liquid, gel, or solid.

[0112] In some embodiments, the electrode assembly 2 includes tabs 22 , which can conduct current from the electrode body 21 or introduce current into the electrode body 21 . The tabs 22 include a positive electrode tab 221 and a negative electrode tab 222 .

[0113] The electrode terminal 3 is provided through a mounting hole in the first wall 11 of the housing 1 and is partially located within the accommodating cavity 1a of the housing 1. The electrode terminal 3 is used to directly or indirectly electrically connect to the tab 22 of the electrode assembly 2 to output electrical energy to or input electrical energy to the electrode body 21 of the electrode assembly 2.

[0114] The first wall 11 is a wall surface of the housing 1 for mounting the electrode terminal 3. The first wall 11 and the other walls of the housing 1 together form a housing cavity 1a for accommodating the electrode assembly 2. In the embodiment of the present application, the electrode terminal 3 is mounted on the end cap, that is, the end cap constitutes the first wall 11 of the housing 1. In some other embodiments, if the electrode terminal 3 is mounted on another wall surface of the housing 1, the wall surface on which the electrode terminal 3 is mounted constitutes the first wall 11.

[0115] For example, the number of electrode terminals 3 may be only one, and the electrode terminal 3 is connected to one of the positive electrode tab 221 or the negative electrode tab 222, and the other of the positive electrode tab 221 or the negative electrode tab 222 is connected to the housing 1. The number of electrode terminals 3 may also be two, and the two electrode terminals 3 are connected to the positive electrode tab 221 and the negative electrode tab 222, respectively.

[0116] In an embodiment of the present application, the electrode terminal 3 includes a positive terminal 31 and a negative terminal 32, the positive terminal 31 is connected to the positive electrode tab 221, and the negative terminal 32 is connected to the negative electrode tab 222. Therefore, the shell 1 is correspondingly formed with two mounting holes, which are used to mount the positive terminal 31 and the negative terminal 32 respectively. It should be understood by those skilled in the art that in some other embodiments, the number of electrode terminals 3 can be more (more than two). When the number of electrode terminals 3 is multiple, the multiple electrode terminals 3 can be mounted on the same wall surface of the shell 1, or on different wall surfaces of the shell 1. When the multiple electrode terminals 3 are respectively mounted on different wall surfaces of the shell 1, each wall surface on which the electrode terminal 3 is mounted can be constituted as the first wall 11.

[0117] Exemplarily, the electrode terminal 3 may be, for example, a pole, and the electrode terminal 3 may be made of a conductive material to achieve the conductive function of the electrode terminal 3 .

[0118] In the embodiment of the present application, the electrode terminal 3 is electrically connected to the tab 22 of the electrode assembly 2 via the electrical connector 4. The electrical connector 4 may also be referred to as a transition piece.

[0119] like Figures 6 to 8 As shown, the electrical connector 4 includes a tab connection portion 41, an electrode terminal connection portion 42, and an intermediate connection portion 43. The tab connection portion 41 is a structure in the electrical connector 4 for connecting to the tab 22, and the electrode terminal connection portion 42 is a structure in the electrical connector 4 for connecting to the electrode terminal 3.

[0120] Illustratively, the tab 22 is welded to the tab connection portion 41 by an ultrasonic welding process, and the electrode terminal 3 is welded to the electrode terminal connection portion by a laser welding process.

[0121] Of course, those skilled in the art should understand that in some other embodiments, the tab 22 and the electrode terminal 3 may also be connected to the tab connecting portion 41 and the electrode terminal connecting portion 42 respectively in any other suitable manner.

[0122] The intermediate connection portion 43 is a component of the electrical connector 4 that connects the tab connection portion 41 and the electrode terminal connection portion 42 . The tab connection portion 41 and the electrode terminal connection portion 42 are located on opposite sides of the intermediate connection portion 43 along the second direction.

[0123] In some embodiments, the width direction of the electrical connector 4 may be a first direction, and the length direction of the electrical connector 4 may be a second direction. Figure 7 and Figure 8 In the specific example shown, Figure 7 and Figure 8 The up and down direction is the first direction of the embodiment of the present application, and the left and right direction is the second direction of the embodiment of the present application.

[0124] In some embodiments, the thickness direction of the battery cell 100 can also be referred to as the first direction, and the direction relative to the large surface (the wall with the largest area) of the housing 1 can also be referred to as the first direction. The first direction can also be the direction in which the positive electrode sheet 211, the negative electrode sheet 212, and the separator 213 of the electrode body 21 are stacked. Those skilled in the art will understand that when the electrode body 21 has a wound structure, the electrode body 21 includes curved sections and straight sections. In this case, the stacking direction of the positive electrode sheet, the negative electrode sheet, and the separator in the straight section is the first direction.

[0125] In some embodiments, the intermediate connection portion 43 can be set as a fuse portion, that is, the intermediate connection portion 43 includes a thinning area and / or a fuse hole, so that the current exceeds the rated value, that is, when the current is too large, the intermediate connection portion 43 can be melted, thereby disconnecting the connection between the tab connection portion 41 and the electrode terminal connection portion 42, thereby cutting off the electrical connection between the tab 22 and the electrode terminal 3, reducing the possibility of short circuit in the battery cell 100, and making the battery cell 100 more reliable.

[0126] Exemplarily, the electrical connector 4 may be formed as an integrated structure. For example, a plate-like member may be prepared by processes such as stamping, bending, and cutting to form the integrated electrical connector 4 .

[0127] As another example, the tab connection portion 41 , the electrode terminal connection portion 42 and the intermediate connection portion 43 of the electrical connector 4 may be separate structures and then assembled together.

[0128] In the related art, the tab is usually located as a whole below the electrical connector and is connected to the electrical connector in a state of being bent at approximately 90°. Therefore, the tab occupies a large space along the height direction of the battery cell (the third direction), which is not conducive to the space utilization within the battery cell, resulting in the electrode body of the electrode assembly occupying a smaller space. The volume of the electrode body is positively correlated with the energy density of the battery cell. Therefore, a reduction in the volume of the electrode body will affect the energy density of the battery cell.

[0129] In the embodiments of this application, Figure 4 and Figure 5 As shown, the pole tab connection portion 41 has a accommodating space 10 on at least one side along the first direction, and at least part of the pole tab 22 is accommodated in the accommodating space 10. As a result, the accommodating space 10 on the side of the electrical connector 4 can be fully utilized, so that part of the pole tab 22 is located on the side of the electrical connector 4, rather than all of it is located below the electrical connector 4, thereby reducing the space occupied by the pole tab 22 in the height direction (third direction), which is beneficial to improving the space utilization rate in the shell 1 of the battery cell 100, reserving more space for the electrode body 21, and then being able to appropriately increase the volume of the electrode body 21 without changing the size of the shell 1 of the battery cell 100, thereby improving the energy density of the battery cell 100.

[0130] Specifically, if Figure 4 and Figure 5 As shown, along the third direction, the spatial area between the inner wall surface of the first wall 11 facing the accommodating cavity 1a and the second surface 412 of the tab connecting portion 41, and along the first direction, the spatial area between the tab connecting portion 41 and the inner wall surface of the shell 1, the two spatial areas jointly define an accommodating space 10 for accommodating at least part of the tab 22.

[0131] The embodiment of the present application does not impose any specific limitation on the formation method of the accommodation space 10 , as long as there is enough space to accommodate the tab 22 .

[0132] Exemplarily, the tab connection portion 41 has an accommodation space 10 on both opposite sides along the first direction. Exemplarily, the tab connection portion 41 has an accommodation space 10 only on one side along the first direction. The specific setting can be made based on the lead-out method and number of the tabs 22 of the actual electrode assembly 2.

[0133] In some embodiments of the present application, the tab connection portion 41 includes a first surface 411 and a second surface 412 facing away from each other along a third direction. The first surface 411 faces the first wall 11, and the second surface 412 faces away from the first wall 11. The tab 22 includes a welding portion 223 and a bent portion 224. The welding portion 223 is connected to the bent portion 224. The welding portion 223 is welded to the second surface 412 of the tab connection portion 41. The bent portion 224 protrudes relative to the welding portion 223 along the third direction toward the side of the first wall 11. The bent portion 224 is accommodated in the accommodation space 10. The third direction is perpendicular to both the first and second directions.

[0134] like Figures 3 to 5 As shown, the tab 22 includes a welding portion 223 and a bent portion 224. The welding portion 223 is generally flat, which makes it easier to weld to the tab connection portion 41. One end of the bent portion 224 is connected to the welding portion 223, and the other end is connected to the electrode body 21. The bent portion 224 protrudes along the third direction toward the side where the first wall 11 is located relative to the welding portion 223 and is accommodated in the accommodating space 10.

[0135] When observed along the second direction, the cross-section of the bending portion 224 of the embodiment of the present application is generally in an inverted U-shape, and one side wall of the bending portion 224 is generally inclined. In this way, the inclined side wall is not easy to interfere with the insulating part 5 (lower plastic) in the shell 1, and can make more full use of the space between the pole ear connecting portion 41 and the inner wall of the shell 1 to accommodate the bending portion 224 of the pole ear 22.

[0136] In some other embodiments, when viewed along the second direction, the cross-section of the bent portion 224 may also be a relatively regular inverted U-shape, or any other suitable shape such as a step-like shape. Those skilled in the art will appreciate that the embodiment of the present application does not impose any specific limitation on the shape of the bent portion 224, as long as the bent portion 224 can be accommodated within the accommodation space 10.

[0137] Therefore, by changing the bending mode of the tab 22, the structure of the tab 22 can be made more compact, and the overall size along the third direction can be smaller, so that the tab 22 occupies less space, saving space in the accommodating cavity 1a of the shell 1, and thereby increasing the space in the accommodating cavity 1a for accommodating the electrode body 21, which is beneficial to improving the energy density of the battery cell 100.

[0138] Moreover, the bent portion 224 of the tab 22 is accommodated in the accommodation space 10 , which can fully utilize the space on the side of the tab connecting portion 41 , further saving the space in the accommodation cavity 1 a of the shell 1 , and is more conducive to improving the energy density of the battery cell 100 .

[0139] In some embodiments of the present application, along the third direction, the difference between the first dimension and the second dimension is greater than or equal to 0 mm (millimeter) and less than or equal to 3 mm (millimeter), wherein the first dimension is the distance dimension between the top surface of the bending portion 224 and the first wall 11, and the second dimension is the distance dimension between the first surface 411 of the tab connecting portion 41 and the first wall 11.

[0140] For example, the difference between the first size and the second size may be 0 mm, 0.5 mm, 1 mm, 1.5 mm, 2 mm, 2.5 mm or 3 mm, etc.

[0141] The top surface of the bent portion 224 refers to the surface of the bent portion 224 that is closest to the first wall 11 along the first direction.

[0142] Therefore, along the third direction, the top surface of the bent portion 224 is substantially flush with the first surface 411 of the pole tab connecting portion 41, or slightly higher than the first surface 411 of the pole tab connecting portion 41. In this way, the area of the accommodating space 10 along the height direction can be fully utilized to accommodate more pole tabs 22, thereby providing a larger space for the electrode body 21 and increasing the energy density of the battery cell 100.

[0143] Flush means that the top surface of the bent portion 224 and the first surface 411 of the tab connecting portion 41 are substantially in the same horizontal plane.

[0144] Of course, those skilled in the art should understand that in some other embodiments, for example, when the length of the tab 22 is shorter, the top surface of the bent portion 224 may also be lower than the first surface 411 of the tab connecting portion 41, and the user may set it according to actual conditions.

[0145] In some embodiments of the present application, at least a portion of the tab connecting portion 41 is recessed along the first direction to form a groove portion 413 , and the groove portion 413 defines at least a portion of the accommodation space 10 .

[0146] like Figures 6 to 8As shown, the dimension of the pole tab connection portion 41 along the first direction is smaller than the dimension of the electrode terminal connection portion 42 along the first direction, and at least a portion of the pole tab connection portion 41 is recessed along the first direction to form a groove portion 413. Thus, the groove portion formed by the pole tab connection portion 41 can constitute at least a portion of the accommodating space 10 for accommodating the bent portion 224 of the pole tab 22, thereby increasing the energy density of the battery cell 100 without changing the size of the shell 1 of the battery cell 100.

[0147] Exemplarily, the accommodation space 10 may be completely defined by the groove portion 413 .

[0148] As another example, the accommodating space 10 can be only partially defined by the groove portion 413, that is, there is also a certain spacing area between the outermost edge of the electrical connector 4 and the inner wall of the shell 1. Then the accommodating space 10 can be jointly defined by the groove portion 413 and the spacing area between the outermost edge of the electrical connector 4 and the inner wall of the shell, and the groove portion 413 is part of the accommodating space 10.

[0149] like Figure 6 and Figure 7 As shown, along the second direction, the groove portion 413 may entirely penetrate the tab connection portion 41 , that is, at least one side of the tab connection portion 41 along the first direction is entirely recessed along the first direction to form the groove portion 413 .

[0150] like Figure 8 As shown, along the second direction, the groove portion 413 may also only partially penetrate the tab connection portion 41 , that is, a portion of at least one side of the tab connection portion 41 along the first direction is recessed along the first direction to form the groove portion 413 .

[0151] In the embodiment of the present application, the groove portion 413 is generally rectangular in shape. In some other embodiments, the groove portion 413 may also be trapezoidal, polygonal, or any other suitable shape.

[0152] The embodiment of the present application does not impose any specific restrictions on the formation position and shape of the groove portion 413 on the tab connecting portion 41 . The user can set the position and shape of the groove portion 413 according to the actual extension position and shape of the tab 22 .

[0153] When the tab connecting portion 41 is formed with grooves 413 on two opposite sides along the first direction, the shapes and sizes of the two grooves 413 may be the same or different.

[0154] In some embodiments of the present application, the battery cell 100 further includes an insulating member 5, which is located on the side of the first wall 11 facing the electrode assembly 2. Along the first direction, the width of the bent portion 224 is smaller than the distance between the bottom wall 4131 of the groove portion 413 and the outer edge of the insulating member 5.

[0155] The insulating member 5 is made of an insulating material and is located between the first wall 11 and the electrode assembly 2. The insulating member 5 can be prefabricated from a plastic integral part or assembled from various plastic parts. When the housing 1 is made of a metal material, the insulating member 5 can electrically insulate the electrode assembly 2 from the first wall 11, reducing the possibility of a short circuit caused by contact between the tab 22 and the first wall 11 made of a metal material. In addition, the insulating member 5 can also provide a certain degree of support for the electrode assembly 2, reducing the possibility of the electrode assembly 2 moving inside the accommodating chamber 1a.

[0156] Exemplarily, the insulating member 5 may be a plastic frame.

[0157] The bottom wall 4131 of the groove portion 413 refers to the wall surface of the groove portion 413 farthest from the inner wall of the shell 1 along the first direction, and the outer edge of the insulating member 5 refers to the edge of the insulating member 5 close to the inner wall of the shell 1 along the first direction.

[0158] In this way, while ensuring the good appearance of the tab 22, the bent portion 224 of the tab 22 can be better accommodated in the accommodating space 10, thereby saving the space occupied by the tab 22 in the accommodating cavity 1a along the third direction, which is conducive to improving the energy density of the battery cell 100. In addition, the tab 22 is less likely to come into contact with the housing 1, reducing the possibility of a short circuit in the battery cell 100.

[0159] Specifically, along the first direction, the distance between the bottom wall 4131 of the groove portion 413 and the outer edge of the insulating member 5 is greater than or equal to a third dimension. The third dimension is the sum of the distance between the housing 1 and the insulating member 5 along the first direction and half the width of the tab connecting portion 41 along the first direction.

[0160] like Figure 5 and Figure 7 As shown, the distance between the bottom wall 4131 of the groove portion 413 and the outer edge of the insulating member 5 is q, the distance between the housing 1 and the insulating member 5 along the first direction is a, and the width of the tab connection portion 41 along the first direction is b.

[0161] Typically, the width of the tab connection portion 41 along the first direction is greater than 8 mm, which is beneficial for flow and welding of the tab connection portion 41 and the tab 22. The distance between the housing 1 and the insulating member 5 along the first direction is 2 mm.

[0162] Therefore, when q is greater than or equal to 6 mm, the accommodation space 10 can have enough space to accommodate the bent portion 224 of the tab 22 .

[0163] In addition, the distance between the bottom wall 4131 of the groove portion 413 and the outer edge of the insulating member 5 is less than or equal to a fourth dimension, which is half the thickness of the battery cell 100 along the first direction minus the third dimension.

[0164] like Figure 4 As shown, the thickness of the battery cell 100 along the first direction is l, then

[0165] Typically, l is greater than 24 mm and the third dimension is greater than or equal to 6 mm.

[0166] Therefore, the tab connection portion 41 can form the groove portion 413 while also meeting the overcurrent requirement of the tab connection portion 41 and the requirement for welding with the welding portion 223 of the tab 22 .

[0167] In some embodiments of the present application, along the first direction, the width of the groove portion 413 is less than or equal to half the width of the electrical connector 4 .

[0168] like Figure 7 As shown, the width of the groove portion 413 along the first direction is u, and the width of the electrical connector 4 along the first direction is t.

[0169] When u is greater than When the tab 22 is welded to the tab connection portion 41 , the groove portion 413 will exceed the central axis of the tab connection portion 41 , so that the tab connection portion 41 will be eccentric. Therefore, at least the tab 22 on one side of the tab connection portion 41 along the first direction needs to be extended so that the tab 22 can be welded to the tab connection portion 41 .

[0170] Therefore, it is necessary to make u less than or equal to As a result, the tab 22 can be well welded to the tab connection portion 41 without being excessively stretched, thereby reducing the possibility of redundant tabs 22 and effectively reducing production costs.

[0171] Those skilled in the art should understand that when the tab connection portion 41 is formed with grooves 413 on both sides of the opposite sides along the first direction, the dimensions u of the two grooves 413 along the first direction are both smaller than Or the dimension u of a groove portion 413 along the first direction is equal to The dimension u of the other groove portion 413 along the first direction is smaller than Thereby, the tab connecting portion 41 has enough space to be welded to the welding portion 223 of the tab 22 .

[0172] In some embodiments of the present application, the width of the groove portion 413 along the first direction is greater than or equal to a fifth dimension, wherein the fifth dimension is the distance between the bottom wall 4131 of the groove portion 413 and the housing 1 along the first direction minus the distance between the electrical connector 4 and the housing 1 along the first direction.

[0173] Typically, the distance between the bottom wall 4131 of the groove portion 413 and the housing 1 along the first direction is 8 mm. In addition, since there is a spacing between both sides of the electrical connector 4 along the first direction and the inner wall of the housing 1, the distance between the electrical connector 4 and the housing 1 along the first direction is equal to the thickness l of the battery cell 100 along the first direction minus the dimension t of the electrical connector 4 along the first direction divided by 2.

[0174] As a result, at least one side of the tab connection portion 41 along the first direction has enough space to accommodate the bent portion 224 of the tab 22 , thereby facilitating improvement of the energy density of the battery cell 100 .

[0175] In some embodiments of the present application, along the second direction, the length of the groove portion 413 is less than or equal to the length of the electrical connector 4 , and greater than or equal to the length of the tab 22 plus an error dimension.

[0176] The error size refers to the process error caused by machining the tab 22 or bending the tab 22 . Typically, the error size is ±8 mm.

[0177] Thus, the groove portion 413 can better accommodate the bent portion 224 of the tab 22 along the length direction (second direction), reducing the possibility of interference between the groove sidewall of the groove portion 413 and the bent portion 224, and improving the reliability of the battery cell 100.

[0178] In some embodiments of the present application, the electrode terminal connection portion 42 and the tab connection portion 41 extend along the second direction, the intermediate connection portion 43 extends along the third direction, and the tab connection portion 41 is arranged closer to the first wall 11 than the electrode terminal connection portion 42 in the third direction. The third direction is perpendicular to both the first direction and the second direction.

[0179] like Figure 6 As shown, when observed along the first direction, the electrical connector 4 is generally Z-shaped, that is, there is a certain height difference between the pole tab connection portion 41 and the electrode terminal connection portion 42, and the pole tab connection portion 41 is arranged close to the first wall 11 along the third direction, thereby making full use of the space on the side of the first wall 11 facing the accommodating cavity 1a to accommodate the bending portion 224, that is, making full use of the space generated by the height difference between the pole tab connection portion 41 and the electrode terminal connection portion 42, thereby further saving the size of the pole tab 22 along the third direction, reserving more space for the electrode body 21, and improving the energy density of the battery cell 100.

[0180] Of course, those skilled in the art should understand that in some other embodiments, the electrical connector 4 as a whole may also be in the shape of a flat plate. The embodiment of the present application does not specifically limit the shape of the electrical connector 4 and may be specifically set according to actual conditions.

[0181] In some embodiments of the present application, there are two grooves 413 , which are located on opposite sides of the tab connection portion 41 along the first direction. The two grooves 413 may have the same or different shapes and sizes.

[0182] Therefore, the shape and size of the groove portion 413 can be set according to the actual lead-out shape and size of the electrode tab 22 , thereby adapting to different forms of the electrode tab 22 .

[0183] For example, in the embodiment of the present application, the two groove portions 413 are both substantially rectangular in shape, and the two groove portions 413 have the same size.

[0184] For example, in some other embodiments, the shapes of the two groove portions 413 are different, and the sizes of the two groove portions 413 are also different.

[0185] In some embodiments of the present application, the tab connection portion 41 is flat and / or the electrode terminal connection portion 42 is flat.

[0186] This makes it easier for the electrode terminal 3 and the tab 22 to be connected to the electrode terminal connecting portion 42 and the tab connecting portion 41, respectively, thereby improving the reliability of the electrical connector 4.

[0187] Of course, those skilled in the art should understand that in some other embodiments, the tab connection portion 41 and the electrode terminal connection portion 42 may also be in any other suitable shapes.

[0188] In some embodiments of the present application, the electrode terminal 3 includes a positive terminal 31 and a negative terminal 32. The electrical connector 4 includes a first electrical connector 44 and a second electrical connector 45. The tab 22 includes a positive tab 221 and a negative tab 222. The positive tab 221 is located on the same side as the positive terminal 31, and / or the negative tab 222 is located on the same side as the negative terminal 32. The positive tab 221 is connected to the positive terminal 31 via the first electrical connector 44, and the negative tab 222 is connected to the negative terminal 32 via the second electrical connector 45.

[0189] Thus, at least part of the positive electrode tab 221 can be accommodated in the accommodation space 10 provided on at least one side of the first electrical connector 44 along the first direction, and at least part of the negative electrode tab 222 can be accommodated in the accommodation space 10 provided on at least one side of the second electrical connector 45 along the first direction, thereby reducing the dimensions of the positive electrode tab 221 and the negative electrode tab 222 along the third direction, reserving a larger space for the electrode body 21 in the accommodation cavity 1a, which is beneficial to improving the energy density of the battery cell 100.

[0190] Those skilled in the art should understand that the positive electrode tab 221 and the negative electrode tab 222 can be set at any end of the electrode body 21, and the embodiment of the present application does not specifically limit the setting positions of the two.

[0191] In addition, since the positive electrode tab 221 and the positive terminal 31 are located on the same side, and / or the negative electrode tab 222 and the negative terminal 32 are located on the same side, it is easier to connect the tab 22 and the electrode terminal 3, and it can save space in the battery cell shell, which is beneficial to improving the energy density of the battery cell.

[0192] Illustratively, the positive electrode tab 221 is located on the same side as the positive electrode terminal 31 , and the negative electrode tab 222 is located on the same side as the negative electrode terminal 32 .

[0193] As another example, the positive electrode tab 221 and the positive electrode terminal 31 are located on the same side, and the negative electrode tab 222 and the negative electrode terminal 32 are located on different sides.

[0194] As another example, the positive electrode tab 221 and the positive electrode terminal 31 are located on different sides, and the negative electrode tab 222 and the negative electrode terminal 32 are located on the same side.

[0195] Those skilled in the art should understand that when the tab 22 and the electrode terminal 3 are located on the same side, the tab connection portion 41 of the electrical connector 4 is generally in the shape of a flat plate extending in one direction, and the positive tab 221 and the negative tab 222 can be located on the same side of the electrode body 21, or on different sides of the electrode body 21.

[0196] Illustratively, the positive electrode tab 221 and the negative electrode tab 222 are located on the same side of the electrode body 21 , and the positive electrode terminal 31 and the negative electrode terminal 32 are located on the same side as the positive electrode tab 221 and the negative electrode tab 222 .

[0197] As another example, the positive electrode tab 221 and the negative electrode tab 222 are located on different sides of the electrode body 21, the positive terminal 31 is located on the same side as the positive electrode tab 221, and the negative terminal 32 is located on the same side as the negative electrode tab 222.

[0198] In some embodiments of the present application, the electrode terminal 3 includes a positive terminal 31 and a negative terminal 32. The electrical connector 4 includes a first electrical connector 44 and a second electrical connector 45. The tab 22 includes a positive tab 221 and a negative tab 222. The positive tab 221 is located on a different side from the positive terminal 31, and / or the negative tab 222 is located on a different side from the negative terminal 32. The positive tab 221 is connected to the positive terminal 31 via the first electrical connector 44, and the negative tab 222 is connected to the negative terminal 32 via the second electrical connector 45.

[0199] Thus, at least part of the positive electrode tab 221 can be accommodated in the accommodation space 10 provided on at least one side of the first electrical connector 44 along the first direction, and at least part of the negative electrode tab 222 can be accommodated in the accommodation space 10 provided on at least one side of the second electrical connector 45 along the first direction, thereby reducing the dimensions of the positive electrode tab 221 and the negative electrode tab 222 along the third direction, reserving a larger space for the electrode body 21 in the accommodation cavity 1a, which is beneficial to improving the energy density of the battery cell 100.

[0200] In addition, since the positive electrode tab 221 and the positive terminal 31 are located on different sides, and / or the negative electrode tab 222 and the negative terminal 32 are located on different sides, this is beneficial to improving the flexibility of connecting the tab 22 and the electrode terminal 3, and when multiple battery cells 100 are grouped, it is beneficial to improve the connection flexibility between the battery cells 100.

[0201] Illustratively, the positive electrode tab 221 is located on a different side from the positive electrode terminal 31 , and the negative electrode tab 222 is located on a different side from the negative electrode terminal 32 .

[0202] As another example, the positive electrode tab 221 and the positive electrode terminal 31 are located on the same side, and the negative electrode tab 222 and the negative electrode terminal 32 are located on different sides.

[0203] As another example, the positive electrode tab 221 and the positive electrode terminal 31 are located on different sides, and the negative electrode tab 222 and the negative electrode terminal 32 are located on the same side.

[0204] Those skilled in the art should understand that when the tab 22 and the electrode terminal 3 are located on different sides, the tab connection portion 41 of the electrical connector 4 is generally "L"-shaped or inverted "L"-shaped, that is, the tab connection portion 41 includes two sections extending in different directions, one of which is in the same extension direction as the electrode terminal connection portion 42, and the other section is perpendicular to the extension direction of the electrode terminal connection portion 42, thereby connecting the electrode terminal 3 and the tab 22 located on different sides.

[0205] In addition, when the tab 22 and the electrode terminal 3 are located on different sides, the positive tab 221 and the negative tab 222 can also be located on the same side of the electrode body 21 or on different sides of the electrode body 21 .

[0206] Illustratively, the positive electrode tab 221 and the negative electrode tab 222 are located on the same side of the electrode body 21, and the positive terminal 31 and the negative terminal 32 are located on a side different from the side where the positive electrode tab 221 and the negative electrode tab 222 are located. At this time, the positive terminal 31 and the negative terminal 32 can be located on the same side or on different sides.

[0207] As another example, the positive electrode tab 221 and the negative electrode tab 222 are located on different sides of the electrode body 21 , and the positive terminal 31 and the negative terminal 32 are located on sides different from the positive electrode tab 221 and the negative electrode tab 222 .

[0208] As another example, the positive electrode tab 221 , the negative electrode tab 222 , the positive electrode terminal 31 , and the negative electrode terminal 32 may be located on four different sides, respectively.

[0209] In some embodiments of the present application, there are multiple electrode assemblies 2 , which are arranged in parallel along the first direction, and the tabs 22 of the multiple electrode assemblies 2 with the same polarity are connected through the same electrical connector 4 .

[0210] Multiple electrode assemblies 2 can increase the energy density of the battery cell 100. Furthermore, connecting the tabs 22 of the same polarity of multiple electrode assemblies 2 through the same electrical connector 4 can reduce the assembly steps of the battery cell 100, lower the assembly difficulty, and help reduce production costs.

[0211] The second aspect of the present application provides an electrical connector 4 for a battery cell 100, wherein the thickness direction of the battery cell 100 is a first direction, and the electrical connector 4 includes a tab connection portion 41, an electrode terminal connection portion 42, and an intermediate connection portion 43. The tab connection portion 41 is used to connect to the tab 22 of the battery cell 100. The electrode terminal connection portion 42 is used to connect to the electrode terminal 3 of the battery cell 100. The intermediate connection portion 43 connects the tab connection portion 41 and the electrode terminal connection portion 42, and the tab connection portion 41 and the electrode terminal connection portion 42 are located on opposite sides of the intermediate connection portion 43 along a second direction, and the second direction is perpendicular to the first direction. The tab connection portion 41 has an accommodating space 10 on at least one side along the first direction, and the accommodating space 10 is used to accommodate at least part of the tab 22.

[0212] Since the tab connection portion 41 of the electrical connector 4 has an accommodating space 10 on at least one side along the first direction, and the accommodating space 10 can be used to accommodate at least part of the tab 22, the accommodating space 10 on the side of the electrical connector 4 along the first direction can be fully utilized to reduce the space occupied by the tab 22 in the height direction (third direction), so that the tab 22 is not located as a whole below the electrical connector 4, which is beneficial to improving the space utilization rate within the shell 1 of the battery cell 100 and reserving more space for the electrode body 21. As a result, the volume of the electrode body 21 can be appropriately increased without changing the size of the shell 1 of the battery cell 100, thereby improving the energy density of the battery cell 100.

[0213] A third aspect of the present application provides a battery device 400 , which includes a box body 401 and at least one battery cell 100 as described in the first aspect of the present application. The battery cell 100 is accommodated in the box body 401 .

[0214] The battery device 400 provided in the present application includes the battery cell 100 provided in the first aspect above. Therefore, the space occupied by the tab 22 along the third direction can be reduced, and the space occupied by the electrode body 21 can be increased, which is beneficial to improving the energy density of the battery cell 100, thereby improving the energy density of the battery device 400.

[0215] A fourth aspect of the present application provides an electrical device, which includes the battery cell 100 described in the first aspect of the present application or the battery device 400 described in the third aspect of the present application for providing electrical energy.

[0216] The electrical device of the embodiment of the present application includes the battery cell 100 provided in the first aspect or the battery device 400 provided in the third aspect. Therefore, the space occupied by the tab 22 of the battery cell 100 along the third direction can be reduced, and the space occupied by the electrode body 21 can be increased, which is beneficial to improving the energy density of the battery cell 100, thereby improving the energy density of the battery device 400, and thus extending the power supply time of the battery cell 100 or the battery device 400 to the electrical device.

[0217] The fifth aspect of the present application provides an energy storage device, which includes the battery cell 100 described in the first aspect of the present application or the battery device 400 described in the third aspect of the present application for providing electrical energy.

[0218] The energy storage device of the embodiment of the present application includes the battery cell 100 provided in the first aspect or the battery device 400 provided in the third aspect. Therefore, the space occupied by the tab 22 of the battery cell 100 along the third direction can be reduced, thereby increasing the space occupied by the electrode body 21, which is beneficial to improving the energy density of the battery cell 100, thereby increasing the energy density of the battery device 400, and thus extending the power supply time of the battery cell 100 or the battery device 400 to the energy storage device.

[0219] Below, some specific examples of embodiments of the present application are described with reference to the accompanying drawings.

[0220] As a specific example, the battery cell (battery cell 100) includes a transition piece (electrical connector 4), a bare battery cell (electrode body 21) and a tab 22, and the tab is connected to the bare battery cell. By narrowing the width of the transition piece body (tab connection portion 41) in the ultrasonic welding area in the thickness direction of the battery cell (first direction), a groove (groove portion 413) is formed, and a cavity (accommodation space 10) is reserved between the transition piece and the plastic (insulating member 5) for accommodating the tab, reducing the folded height of the tab, and then reducing the space occupied by the folded tab in the height direction (third direction), thereby increasing the capacity of the bare battery cell and improving the energy density of the battery cell.

[0221] In order to ensure a good folded ear shape, the distance between the edge of the adapter and the edge of the lower plastic must meet the following requirements: The distance between the edge of the adapter and the edge of the lower plastic is q; the thickness of the battery cell is l, and l>24.

[0222] The form of the slots on the edge of the adapter is not limited to rectangular, trapezoidal, or polygonal slots. The slot width u satisfies and lt<16; when lt≥16, no slotting is required; the slot length y satisfies r≥y≥i. The adapter plate length (dimension along the second direction) is r, the adapter plate width (dimension along the first direction) is t, and the tab width (dimension along the second direction) plus the offset dimension is i.

[0223] According to the difference in the position and size of the tabs, the adapter plate can be partially grooved, and the position, shape and size of the grooves on two opposite sides of the adapter plate along the first direction can be the same or different.

[0224] The above embodiments are intended only to illustrate the technical solutions of the present application, and are not intended to limit them. Although the present application has been described in detail with reference to the above embodiments, those skilled in the art should understand that they may modify the technical solutions described in the above embodiments, or replace some or all of the technical features therein with equivalents. Such modifications or replacements do not deviate from the essence of the corresponding technical solutions and are intended to be included in the scope of the present application. In particular, as long as there is no structural conflict, the various technical features described in the various embodiments may be combined in any manner.

Claims

1. A battery cell, characterized in that: The battery cell comprises: A housing is formed with an accommodating cavity therein, the housing comprising a first wall, and the first wall is formed with a mounting hole; an electrode assembly located in the accommodating cavity, the electrode assembly comprising an electrode body and an electrode tab connected to the electrode body, wherein the thickness direction of the electrode body is a first direction; an electrode terminal, passing through the mounting hole; and An electrical connector, comprising a tab connection portion, an electrode terminal connection portion, and an intermediate connection portion, wherein the tab connection portion is connected to the tab, the electrode terminal connection portion is connected to the electrode terminal, and the intermediate connection portion connects the tab connection portion and the electrode terminal connection portion, wherein the tab connection portion and the electrode terminal connection portion are located on opposite sides of the intermediate connection portion along a second direction, wherein the second direction is perpendicular to the first direction; Wherein, at least one side of the tab connecting portion along the first direction has an accommodation space, and at least a portion of the tab is accommodated in the accommodation space.

2. The battery cell according to claim 1, wherein: The tab connecting portion includes a first surface and a second surface facing away from each other along a third direction, wherein the first surface faces the first wall, and the second surface faces away from the first wall; The tab includes a welding portion and a bending portion, the welding portion is connected to the bending portion, the welding portion is welded to the second surface of the tab connecting portion, the bending portion protrudes relative to the welding portion along the third direction toward the side where the first wall is located, and the bending portion is accommodated in the accommodation space; The third direction is perpendicular to both the first direction and the second direction.

3. The battery cell according to claim 2, characterized in that: Along the third direction, the difference between the first dimension and the second dimension is greater than or equal to 0 mm and less than or equal to 3 mm, wherein the first dimension is the distance between the top surface of the bending portion and the first wall, and the second dimension is the distance between the first surface of the tab connecting portion and the first wall.

4. The battery cell according to claim 2, characterized in that: At least a portion of the tab connecting portion is recessed along the first direction to form a groove portion, and the groove portion defines at least a portion of the accommodation space.

5. The battery cell according to claim 4, characterized in that The battery cell further includes an insulating member, the insulating member being located on a side of the first wall facing the electrode assembly; Along the first direction, the width of the bent portion is smaller than the distance between the bottom wall of the groove portion and the outer edge of the insulating member.

6. The battery cell according to claim 5, characterized in that Along the first direction, the distance between the bottom wall of the groove portion and the outer edge of the insulating member is greater than or equal to a third dimension; The third dimension is the sum of the distance between the housing and the insulating member along the first direction and half the width of the tab connecting portion along the first direction.

7. The battery cell according to claim 6, characterized in that The distance between the bottom wall of the groove portion and the outer edge of the insulating member is less than or equal to a fourth dimension; The fourth dimension is half of the thickness of the battery cell along the first direction minus the third dimension.

8. The battery cell according to any one of claims 4 to 7, characterized in that: Along the first direction, the width of the groove portion is less than or equal to half the width of the electrical connector.

9. The battery cell according to claim 8, characterized in that Along the first direction, the width of the groove portion is greater than or equal to a fifth dimension; The fifth dimension is the distance between the bottom of the groove and the housing along the first direction minus the distance between the electrical connector and the housing along the first direction.

10. The battery cell according to any one of claims 4 to 7, characterized in that: Along the second direction, the length of the groove portion is less than or equal to the length of the electrical connector, and is greater than or equal to the length of the tab plus an error dimension.

11. The battery cell according to any one of claims 1 to 7, characterized in that: The electrode terminal connection portion and the tab connection portion extend along the second direction, the intermediate connection portion extends along a third direction, and the tab connection portion is closer to the first wall than the electrode terminal connection portion in the third direction.

12. The battery cell according to any one of claims 4 to 7, characterized in that: There are two grooves, and the two grooves are located on opposite sides of the tab connecting portion along the first direction; The shapes and sizes of the two grooves are the same or different.

13. The battery cell according to any one of claims 1 to 7, characterized in that: The tab connection portion is flat; and / or The electrode terminal connecting portion is flat.

14. The battery cell according to any one of claims 1 to 7, characterized in that: The electrode terminals include a positive terminal and a negative terminal; The electrical connector includes a first electrical connector and a second electrical connector; The tab includes a positive tab and a negative tab, the positive tab is located on the same side as the positive terminal, and / or the negative tab is located on the same side as the negative terminal, the positive tab is connected to the positive terminal through the first electrical connector, and the negative tab is connected to the negative terminal through the second electrical connector.

15. The battery cell according to any one of claims 1 to 7, characterized in that: The electrode terminals include a positive terminal and a negative terminal; The electrical connector includes a first electrical connector and a second electrical connector; The electrode tab includes a positive electrode tab and a negative electrode tab, the positive electrode tab and the positive electrode terminal are located on different sides, and / or the negative electrode tab and the negative electrode terminal are located on different sides, the positive electrode tab is connected to the positive electrode terminal through the first electrical connector, and the negative electrode tab is connected to the negative electrode terminal through the second electrical connector.

16. The battery cell according to any one of claims 1 to 7, characterized in that: There are multiple electrode assemblies, and the multiple electrode assemblies are arranged in parallel along the first direction. The electrode tabs with the same polarity of the multiple electrode assemblies are connected through the same electrical connector.

17. An electrical connector for a battery cell, wherein the thickness direction of the battery cell is a first direction, characterized in that: The electrical connector includes: A tab connecting portion, used to connect to the tab of the battery cell; an electrode terminal connecting portion, configured to be connected to an electrode terminal of the battery cell; and an intermediate connecting portion, connecting the tab connecting portion and the electrode terminal connecting portion, wherein the tab connecting portion and the electrode terminal connecting portion are located on opposite sides of the intermediate connecting portion along a second direction, wherein the second direction is perpendicular to the first direction; Wherein, at least one side of the tab connecting portion along the first direction has an accommodating space, and the accommodating space is used to accommodate at least a portion of the tab.

18. A battery device, characterized in that: The battery device comprises: Cabinet; and At least one battery cell according to any one of claims 1 to 16 is accommodated in the case.

19. An electrical device, characterized in that: The electrical device includes the battery cell according to any one of claims 1 to 16 or the battery device according to claim 18 for providing electrical energy.

20. An energy storage device, characterized in that: The energy storage device comprises the battery cell according to any one of claims 1 to 16 or the battery device according to claim 18 for providing electrical energy.

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