Top cover assembly, electrode sheet, battery cell, battery, and electric device

Abstract

A top cover assembly, an electrode sheet, a battery cell, a battery, and an electric device, relating to the technical field of batteries. The top cover assembly comprises: a top cover and poles, wherein the top cover comprises a top cover main body portion and first bent sections, and the two ends of the top cover main body portion are connected to the first bent sections bent relative to the top cover main body portion; and an electrode terminal, comprising poles, wherein the poles are mounted on the first bent sections.

Description

Top cover assembly, pole piece, battery cell, battery and electrical device

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application is based on the Chinese patent application with application number: 202410238840.5 and application date of March 1, 2024, and claims the priority of the Chinese patent application. The entire content of the Chinese patent application is hereby introduced into this application as a reference. Technical Field

[0003] The present application relates to the field of batteries, and more specifically, to a top cover assembly, a pole piece, a battery cell, a battery, and an electrical device. Background Art

[0004] In recent years, new energy vehicles have developed by leaps and bounds. In the field of electric vehicles, power batteries, as the power source of electric vehicles, play an irreplaceable and important role.

[0005] To ensure sufficient battery power, multiple battery cells are typically stacked within a battery casing to maximize the energy density of each cell. However, due to the limitations of the terminal connection method when grouping battery cells, a large amount of space is consumed by the tabs and terminals within the battery cell, limiting the space utilization of the battery cell and seriously affecting its energy density. Summary of the Invention

[0006] The present application provides a top cover assembly, a pole piece, a battery cell, a battery and an electrical device, which improve the space utilization of the battery cell to the battery cell when the size of the battery cell is fixed, thereby improving the energy density of the battery cell, and further improving the energy density of a battery composed of multiple battery cells.

[0007] In the first aspect, an embodiment of the present application provides a top cover assembly, comprising: a top cover and a pole, the top cover comprising a top cover main body and a first bending section, both ends of the top cover main body being connected to a first bending section bent relative to the top cover main body; an electrode terminal, the electrode terminal comprising a pole, and the pole being installed on the first bending section.

[0008] In the above technical solution, by designing the top cover to be bent, the pole is installed on the two longitudinal first bending sections and extends in different directions. Compared with the design scheme of the pole output on the same side or the pole output on the opposite side, on the one hand, the present application can make full use of the lateral space of the battery cell and reduce the consumption of the pole on the longitudinal dimension of the battery cell. When the size of the battery cell is fixed, the volume of the battery cell is increased, the space utilization rate of the battery cell to the battery cell is improved, thereby improving the energy density of the battery cell. On the other hand, when the battery cells are grouped, the poles of adjacent battery cells can be butt-welded, which reduces the use and occupied space of the bars or buses, reduces the space consumption of the battery cells, and improves the space utilization rate of the battery cells to the battery cells.

[0009] In some embodiments, one end of the pole is connected to the first bending segment, the lateral projection of the pole along the X direction falls within the lateral projection of the first bending segment along the X direction, and the outer contour of the lateral projection of the pole along the X direction is spaced apart from the outer contour of the lateral projection of the first bending segment along the X direction.

[0010] In some embodiments, the top cover further includes a second bending section, which is connected to an end of the first bending section away from the top cover main body, and the second bending section is bent relative to the first bending section and extends in a direction away from the top cover main body.

[0011] In some embodiments, the length of the pole protruding from the first bending section along the X direction is greater than or equal to the length of the second bending section protruding from the first bending section along the X direction.

[0012] In some embodiments, the length of the pole protruding from the first bending section along the X direction is H1, and the length of the second bending section protruding from the first bending section along the X direction is H2, satisfying: 0mm

[0013] In some embodiments, the length of the top cover along the X direction is L0, the length of the second bending section protruding from the first bending section along the X direction is H2, and the relationship: 1%≤H2 / L0≤10% is satisfied.

[0014] In some embodiments, the length of the first bending section along the Z direction is H3, the length of the pole along the Z direction is L1, and the following conditions are satisfied: 1<H3 / L1≤4.

[0015] In some embodiments, the length of the first bending section along the Y direction is L2, and the length of the pole along the Y direction is L3, satisfying: 1<L2 / L3≤2.

[0016] ​In a second aspect, an embodiment of the present application provides a pole piece, comprising: a pole piece main body, the pole piece main body comprising a first portion and a second portion connected along the Z direction, the length of the first portion along the X direction being less than the length of the second portion along the X direction, the first portion being formed with a notch, the notch being used to avoid the first bent section;

[0017] A tab is connected to a side of the first portion facing away from the second portion.

[0018] In the above technical solution, by connecting the pole ear to the side of the first part away from the second part, the pole ear extends along the length direction of the pole piece, and the space consumed by the pole ear and the space consumed by the pole column are located on different sides of the battery cell. Compared with setting the pole ear and the pole column on the same side of the pole sheet, the space consumption of the pole ear and the pole column on the battery cell can be reduced, thereby improving the space utilization rate of the battery cell to the battery.

[0019] In some embodiments, the electrode piece is applied to a laminated battery cell, the notches are provided at both ends of the first portion in the X direction, and the distance from the electrode tab to one of the notches is smaller than the distance to the other notch.

[0020] In some embodiments, the pole piece is applied to a wound battery cell, and the plurality of notches divide the first part into multiple sections, each section is provided with the pole ear, and the pole piece includes a plurality of sub-pole pieces connected along the X direction, the second parts of two adjacent sub-pole pieces are connected, and the first parts of two adjacent sub-pole pieces are separated by the notch, and the distance from the pole ear to one of the two adjacent notches is smaller than the distance to the other.

[0021] In a third aspect, an embodiment of the present application provides a battery cell, comprising: a shell having an opening; a battery cell disposed in the shell; and a top cover assembly as described in any one of the above, the top cover assembly being installed in the opening.

[0022] In the above technical solution, the outer contour of any of the above-mentioned battery cells is adapted to the outer contour of the top cover assembly, which can make full use of the lateral space of the battery cell and reduce the space consumption of the battery cell. When the size of the battery cell is fixed, the cell volume of the battery cell is increased, and the space utilization rate of the battery cell to the battery cell is improved, thereby improving the energy density of the battery cell.

[0023] In some embodiments, the positive electrode tab and the negative electrode tab of the battery cell are located on the same side.

[0024] In some embodiments, the electrode terminal further includes: a transition piece, the transition piece including a first section and a second section that are connected and bent relative to each other, the first section being connected to the pole, and the second section being connected to the tab.

[0025] In some embodiments, the battery cell is a laminated type or a wound type.

[0026] In some embodiments, the length of the battery cell along the X direction is L4, which satisfies: 100 mm ≤ L4 ≤ 400 mm.

[0027] In a fourth aspect, an embodiment of the present application provides a battery, comprising: a plurality of battery cells described in any one of the above.

[0028] In the above technical solution, any one of the above battery cells has a higher energy density, so that the energy density of the battery including the battery cell is higher.

[0029] In some embodiments, the poles of at least two adjacent battery cells are arranged opposite to each other and butted against each other.

[0030] In a sixth aspect, an embodiment of the present application provides an electrical device, comprising: a battery as described above, wherein the battery is used to provide electrical energy to the electrical device.

[0031] In the above technical solution, the energy density of the battery is relatively high, so the electrical device including the battery has a relatively long battery life. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without creative work.

[0033] FIG1 is a schematic structural diagram of a vehicle provided in some embodiments of the present application;

[0034] FIG2 is an exploded view of the structure of a battery provided in some embodiments of the present application;

[0035] FIG3 is an exploded view of the structure of a battery cell provided in some embodiments of the present application;

[0036] FIG4 is a schematic diagram of the structure of a battery cell according to some embodiments of the present application;

[0037] FIG5 is a front view of a battery cell provided in some embodiments of the present application;

[0038] FIG6 is a schematic structural diagram of a top cover assembly provided in some embodiments of the present application;

[0039] FIG7 is a front view of a top cover assembly provided in some embodiments of the present application;

[0040] FIG8 is a side view of a top cover assembly provided in some embodiments of the present application;

[0041] FIG9 is a top view of a top cover assembly provided in some embodiments of the present application;

[0042] FIG10 is a schematic diagram of the structure of a laminated battery cell provided in some embodiments of the present application;

[0043] FIG11 is a schematic diagram of the structure of a pole piece of a laminated battery cell provided in some embodiments of the present application;

[0044] FIG12 is a schematic structural diagram of a wound-type battery cell provided in some embodiments of the present application;

[0045] FIG13 is a schematic structural diagram of an electrode sheet of a wound-type battery cell provided in some embodiments of the present application;

[0046] FIG14 is a schematic structural diagram of a housing provided in some embodiments of the present application;

[0047] FIG15 is a schematic diagram of the structure of a battery cell with poles facing both sides provided by some embodiments of the present application;

[0048] FIG16 is a schematic structural diagram of a battery cell with terminals on the same side in the related art;

[0049] FIG17 is a schematic diagram of the structure of a battery cell with terminals on opposite sides in the related art.

[0050] Figure markings: Vehicle 1, battery 10, box body 11, first box body 111, second box body 112, battery cell 12; Shell 13, opening 131; Battery cell 14, Pole piece 141, Pole piece main body 1411, First part 14111, Second part 14112, Tab 142, Pole column consumption space V1, Tab consumption space V2; Top cover assembly 15, Top cover 151, Top cover main body 1511, First bending section 1512, Second bending section 1513, Pole column 152; Adapter 16, First section 161, Second section 162, Motor 20, Controller 30. DETAILED DESCRIPTION

[0051] To make the purpose, technical solutions, and advantages of the embodiments of this application more clear, the technical solutions in the embodiments of this application will be clearly described below in conjunction with the drawings in the embodiments of this application. Obviously, the described embodiments are part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0052] Unless otherwise defined, all technical and scientific terms used in this application have the same meanings as commonly understood by those skilled in the art to which this application belongs. The terms used in the specification of this application 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 the specification and claims of this application and the above-mentioned drawings are intended to cover non-exclusive inclusions. The terms "first" and "second" in the specification and claims of this application or the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order or a primary-secondary relationship.

[0053] References to "embodiments" in this application mean that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the 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 in this application may be combined with other embodiments.

[0054] In the description of this application, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," "connected," and "attached" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integral connections; they may refer to direct connections, indirect connections through an intermediate medium, or internal connections between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on specific circumstances.

[0055] The term "and / or" in this application simply describes an association between related objects, indicating that three possible relationships exist. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this application generally indicates that the related objects are in an "or" relationship.

[0056] The term "multiple" in this application refers to more than two (including two). Similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple pieces" refers to more than two pieces (including two pieces).

[0057] The battery cells mentioned in the embodiments of this application may include lithium-ion secondary battery cells, lithium-ion primary battery cells, lithium-sulfur battery cells, sodium-lithium-ion battery cells, sodium-ion battery cells, or magnesium-ion battery cells, etc., and the embodiments of this application do not limit this. The battery cells may be cylindrical, flat, rectangular, or other shapes, etc., and the embodiments of this application do not limit this. Battery cells are generally divided into three types according to the packaging method: cylindrical battery cells, square battery cells, and soft-pack battery cells, and the embodiments of this application do not limit this.

[0058] The battery referred to in the embodiments of this application refers to a single physical module that includes one or more battery cells to provide higher voltage and capacity. For example, the battery referred to in this application may include a battery module or battery pack. A battery generally includes a casing that encloses one or more battery cells or multiple battery modules. The casing prevents liquids or other foreign matter from affecting the charging or discharging of the battery cells.

[0059] A battery cell is the smallest unit that makes up a battery. It consists of a housing, a battery cell, and other electronic components. The housing is used to house the battery cell and other electronic components.

[0060] A battery cell consists of a positive electrode sheet, a negative electrode sheet, and a separator. A battery cell primarily operates by the movement of metal ions between the positive and negative electrode sheets. The positive electrode sheet includes a positive current collector and a positive active material layer. The positive active material layer is coated on the surface of the positive electrode collector. The uncoated positive electrode collector protrudes from the coated positive electrode collector, and the uncoated positive electrode collector serves as the positive electrode tab. For lithium-ion batteries, for example, the positive electrode collector can be made of aluminum, and the positive electrode active material can be lithium cobalt oxide, lithium iron phosphate, ternary lithium, or lithium manganese oxide. The negative electrode sheet includes a negative current collector and a negative active material layer. The negative active material layer is coated on the surface of the negative electrode collector. The uncoated negative electrode collector protrudes from the coated negative electrode collector, and the uncoated negative electrode collector serves as the negative electrode tab. The negative electrode collector can be made of copper, and the negative electrode active material can be carbon or silicon, among others. In order to ensure that large currents can pass without melting, there are multiple positive electrode tabs and they are stacked together, and there are multiple negative electrode tabs and they are stacked together.

[0061] The material of the diaphragm may be PP (polypropylene) or PE (polyethylene), etc. In addition, the battery core may be a wound structure or a laminated structure, but the embodiments of the present application are not limited thereto.

[0062] New energy vehicles have experienced rapid growth in recent years. Within the electric vehicle sector, power batteries, as the power source, play an irreplaceable and important role. A battery consists of a housing and multiple cells housed within it. As a core component in new energy vehicles, batteries have high requirements for both safety and cycle life.

[0063] In typical power batteries, to achieve sufficient power, multiple battery cells are typically stacked within a battery housing, with the energy density of each cell being maximized. The inventors discovered that, due to the limitations of the terminal connection method when grouping battery cells, a significant amount of space is consumed by the tabs and terminals within the battery cells, limiting the space utilization of the battery cells and significantly hindering the improvement of their energy density.

[0064] Based on the above considerations, in order to further improve the space utilization of battery cells and improve the energy density of battery cells, the inventors have designed a top cover assembly, a pole piece, a battery cell, a battery and an electrical device after in-depth research. The top cover assembly includes a top cover and a pole. The top cover includes a top cover main body, a first bending section and a second bending section. Both ends of the top cover main body are connected to a first bending section bent relative to the top cover main body, and an end of the first bending section away from the top cover main body is connected to a second bending section bent relative to the first bending section and extending in a direction away from the top cover main body; the pole is installed on the first bending section.

[0065] In a top cover assembly of this structure, the top cover is designed to be bent, the poles are installed in the two longitudinal first bending sections and extend in different directions. Compared with the design scheme of poles output on the same side or on the opposite sides, on the one hand, the present application can make full use of the lateral space of the battery cell and reduce the longitudinal space consumption of the poles on the battery cell. When the size of the battery cell is fixed, the volume of the battery cell is increased, and the space utilization rate of the battery cell to the battery cell is improved, thereby increasing the energy density of the battery cell and further increasing the energy density of the battery cell. On the other hand, when the battery cells are grouped, the poles of adjacent battery cells can be butt-welded to reduce the use and occupied space of the bars or buses, reduce the space consumption of the battery cells, and improve the space utilization rate of the battery cells to the battery cell, thereby improving the energy density of the battery cell.

[0066] The batteries disclosed in the embodiments of this application can be used, but are not limited to, in electrical devices such as vehicles, ships, or aircraft. A power supply system comprising the top cover assembly, pole pieces, battery cells, battery cells, or batteries disclosed in this application can be used to construct such an electrical device, thereby increasing the battery's energy density.

[0067] The present invention provides an electrical device that uses a battery as a power source. The electrical device may include, 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, and a spacecraft. 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. The spacecraft may include an airplane, a rocket, a space shuttle, and a spacecraft.

[0068] For the convenience of description, the following embodiments are described by taking a vehicle as an example of an electrical device according to an embodiment of the present application.

[0069] As shown in FIG1 , FIG1 is a schematic structural diagram of a vehicle 1 according to an embodiment of the present application. The vehicle 1 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, etc. A motor 20, a controller 30 and a battery 10 may be provided inside the vehicle 1. The controller 30 is used to control the battery 10 to supply power to the motor 20. For example, a battery 10 may be provided at the bottom, front or rear of the vehicle 1. The battery 10 may be used to power the vehicle 1. For example, the battery 10 may be used as an operating power source for the vehicle 1 and for the circuit system of the vehicle 1, for example, for the working power requirements during the startup, navigation and operation of the vehicle 1.

[0070] In another embodiment of the present application, the battery 10 can not only serve as an operating power source for the vehicle 1 , but also serve as a driving power source for the vehicle 1 , replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1 .

[0071] In order to meet different power requirements, the battery 10 may include a plurality of battery cells 12 , wherein the plurality of battery cells 12 may be connected in series, in parallel, or in hybrid connection, where hybrid connection refers to a mixture of series and parallel connection.

[0072] FIG2 is an exploded view of the structure of a battery 10 according to an embodiment of the present application. The battery 10 includes a housing 11 and a plurality of battery cells 12, which are intended to be housed within the housing 11. The housing 11 is configured to provide assembly space for the battery cells 12, and the housing 11 can have a variety of structures. In some embodiments, the housing 11 can include a first housing body 111 and a second housing body 112, which overlap each other and together define an assembly space for accommodating the battery cells 12. The second housing body 112 can be a hollow structure with one end open. The first housing body 111 can be a plate-like structure, with the first housing body 111 overlapping the open side of the second housing body 112, so that the first housing body 111 and the second housing body 112 jointly define an assembly space. Alternatively, the first housing body 111 and the second housing body 112 can each be a hollow structure with one end open, with the open side of the first housing body 111 overlapping the open side of the second housing body 112. Of course, the box body 11 formed by the first box body 111 and the second box body 112 can be in various shapes, such as a cylinder, a cuboid, etc.

[0073] In the battery 10, the multiple battery cells 12 can be connected in series, in parallel, or in a hybrid connection. A hybrid connection refers to a combination of series and parallel connections within the multiple battery cells 12. The multiple battery cells 12 can be directly connected in series, in parallel, or in a hybrid connection, and then the entire battery 12 can be housed within the housing 11. Alternatively, the battery 10 can be constructed by first connecting multiple battery cells 12 in series, in parallel, or in a hybrid connection to form a module. The multiple battery modules can then be connected in series, in parallel, or in a hybrid connection to form a single unit housed within the housing 11.

[0074] Each battery cell 12 may be a secondary battery 10 or a primary battery 10, or may be a lithium-sulfur battery 10, a sodium-ion battery 10, or a magnesium-ion battery 10, but is not limited thereto. The battery cell 12 may be flat, rectangular, or have other shapes.

[0075] As shown in Figure 3, the battery cell 12 includes a housing, a battery cell 14, and other electronic components. The housing is used to house the battery cell 14 and other electronic components. The housing includes a top cover assembly 15 and a housing 13. The top cover assembly 15 is a component that covers the opening 131 of the housing 13 to isolate the internal environment of the battery cell 12 from the external environment.

[0076] As shown in FIG. 4 and FIG. 5 , the top cover assembly 15 includes a top cover 151 and a pole 152 . The pole 152 is mounted on the top cover 151 .

[0077] Without limitation, the shape of the top cover 151 can be adapted to the shape of the housing 13 to fit the housing 13. Optionally, the top cover 151 can be made of a material with a certain hardness and strength (such as an aluminum alloy). This way, the top cover 151 is less likely to deform when subjected to compression or collision, allowing the battery cell 12 to have higher structural strength and improved reliability. Functional components such as electrode terminals can be provided on the top cover 151. The electrode terminals can be used to electrically connect to the battery cells 14 to output or input electrical energy to or from the battery cell 12. In some embodiments, the top cover 151 can also be provided with a pressure relief mechanism for relieving internal pressure when the internal pressure or temperature of the battery cell 12 reaches a threshold. The top cover 151 can also be made of a variety of materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and this is not particularly limited in the embodiments of the present application. In some embodiments, an insulating component can also be provided on the inside of the top cover 151 to isolate the electrical connection components within the housing 13 from the top cover 151 to reduce the risk of short circuits. For example, the insulating component may be made of plastic, rubber, etc.

[0078] The housing 13 is a component used to cooperate with the top cover 151 to form an internal environment of the battery cell 12 , wherein the formed internal environment can be used to accommodate the battery cell 14 , electrolyte and other components.

[0079] The housing 13 and the top cover 151 may be independent components. As shown in FIG. 3 and FIG. 14 , an opening 131 may be provided on the housing 13 , and the top cover 151 may be placed over the opening 131 to form an internal environment of the battery cell 12 .

[0080] Without limitation, the top cover 151 and the shell 13 can also be integrated. Specifically, the top cover 151 and the shell 13 can form a common connection surface before other components are put into the shell. When the interior of the shell 13 needs to be encapsulated, the top cover 151 is made to cover the shell 13. The shell 13 can be of various shapes and sizes, such as a rectangular parallelepiped, a cylindrical shape, a hexagonal prism, etc. Specifically, the shape of the shell 13 can be determined according to the specific shape and size of the battery cell 14. The material of the shell 13 can be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and the embodiments of the present application do not impose any special restrictions on this.

[0081] According to some embodiments of the present application, as shown in FIG6 , the present application provides a top cover assembly 15 , which is applied to a battery 10 . The top cover assembly 15 includes: a top cover 151 and a pole 152 .

[0082] The top cover 151 includes a top cover body 1511 and a first bending section 1512 . Both ends of the top cover body 1511 are connected to the first bending section 1512 that is bent relative to the top cover body 1511 . The pole 152 is installed in the first bending section 1512 .

[0083] The top cover 151 is used to cooperate with the shell 13 to form an internal environment component of the battery cell 12 . The shape of the top cover 151 can be adapted to the shape of the shell 13 to cooperate with the shell 13 .

[0084] The first bending sections 1512 include two first bending sections 1512 , which are arranged at opposite ends of the top cover main body 1511 along the X direction. One end of the first bending section 1512 is connected to the end of the top cover main body 1511 , and the other end of the first bending section 1512 extends along the longitudinal direction of the battery 10 .

[0085] The top cover body 1511 is spaced apart from the battery cell 14, and the tab 142 is disposed between the top cover body 1511 and the battery cell 14. A pole 152 is mounted on each of the first bent sections 1512 at both ends of the top cover body 1511 along the X-direction. The two poles 152 on the first bent sections 1512 extend in opposite directions along the X-direction, i.e., the two poles 152 extend in two directions, respectively.

[0086] In the top cover assembly 15 of this structure, by designing the top cover 151 to be bent, the pole 152 is installed on two first bent sections 1512 along the Z direction, and the two poles 152 located on the first bent section 1512 extend in opposite directions along the X direction. Compared with the design scheme of poles output on the same side or poles output on the opposite sides, on the one hand, the present application can make full use of the lateral space of the battery cell 12 and reduce the consumption of the longitudinal dimension of the battery cell 12 by the pole 152. When the size of the battery cell 12 is fixed, the volume of the battery cell 14 of the battery cell 12 is increased, and the space utilization rate of the battery cell 14 to the battery cell 12 is improved, thereby improving the energy density of the battery cell 12; on the other hand, when the battery cells 12 are grouped, the poles 152 of adjacent battery cells 12 can be butt-welded, reducing the use and occupied space of the bars or bus bars, reducing the space consumption of the battery cell 12, and improving the space utilization rate of the battery cell to the battery cell 12.

[0087] In some embodiments, as shown in FIG6 , one end of the pole 152 is connected to the first bending section 1512 , the lateral projection of the pole 152 along the X direction falls within the lateral projection of the first bending section 1512 along the X direction, and the outer contour of the lateral projection of the pole 152 along the X direction is spaced apart from the outer contour of the lateral projection of the first bending section 1512 along the X direction.

[0088] In this embodiment, the pole 152 is spaced apart from the edge of the first bending section 1512 so as to reduce the distance between adjacent battery cells 12 when multiple battery cells 12 are combined, reduce the space consumed by the pole 152, and further improve the energy density of the battery 10 composed of multiple battery cells 12.

[0089] In some embodiments, the top cover 151 further includes a second bending section 1513 , which is connected to one end of the first bending section 1512 away from the top cover main body 1511 . The second bending section 1513 is bent relative to the first bending section 1512 and extends in a direction away from the top cover main body 1511 .

[0090] In this embodiment, one end of the first bending section 1512 away from the top cover main body 1511 is connected to a second bending section 1513 that is bent relative to the first bending section 1512 and extends away from the top cover main body 1511 .

[0091] The second bending section 1513 is provided to facilitate the installation and matching of the top cover 151 and the shell 13 , thereby increasing the stability of the connection between the top cover 151 and the shell 13 .

[0092] In some embodiments, as shown in FIG. 7 , the length of the pole 152 protruding from the first bending section 1512 along the X direction is greater than or equal to the length of the second bending section 1513 protruding from the first bending section 1512 along the X direction.

[0093] Among them, the end of the pole 152 can be flush with the end of the second bending section 1513 away from the first bending section 1512, which can not only realize the butt welding between the poles 152 of adjacent battery cells 12, but also reduce the distance between adjacent battery cells 12, thereby improving the energy density of the battery 10 composed of multiple battery cells 12.

[0094] Alternatively, the end of the pole 152 may also be larger than the length of the second bent section 1513 protruding from the first bent section 1512 along the X direction, so as to realize butt welding between the poles 152 of adjacent battery cells 12 without the need for a bus bar or adapter plate, thereby improving the space utilization of the battery cell 14 to the battery 10, thereby improving the energy density of the battery 10 composed of multiple battery cells 12.

[0095] In some embodiments, as shown in FIG. 7 , the length of the pole 152 protruding from the first bending section 1512 along the X direction is H1 , and the length of the second bending section 1513 protruding from the first bending section 1512 along the X direction is H2 , satisfying: 0 mm < H1 − H2 ≤ 3 mm.

[0096] Among them, the difference between H1 and H2 can be 1mm, 1.5mm, 2mm or 3mm, that is, the end of the pole 152 protrudes from the end of the second bending section 1513 away from the first bending section 1512, so as to realize butt welding between the poles 152 of adjacent battery cells 12, without the need for a bus bar or adapter, thereby improving the space utilization of the battery cell 14 to the battery 10, thereby improving the energy density of the battery 10 composed of multiple battery cells 12.

[0097] In this embodiment, by setting the positional relationship between the pole 152 and the end of the second bending section 1513 away from the first bending section 1512, adjacent battery cells 12 can be welded together by butt welding of the pole 152. Compared with the solution in which two poles 152 extend in the same direction and a bus or adapter plate is required to connect the two battery cells 12 together, the butt welding of the present application reduces the use of bus plates or bus bars and the occupied space, saves more welding space, and improves the space utilization of the battery cell 14 to the battery 10, thereby improving the energy density of the battery 10 composed of multiple battery cells 12.

[0098] In some embodiments, as shown in FIG. 7 , the length of the first bending section 1512 along the Z direction is H3 , and the length of the pole 152 along the Z direction is L1 , satisfying: 1<H3 / L1≤4.

[0099] Among them, the ratio of H3 to L1 can be 1.5, 2, 3 or 4, that is, the length of the first bending section 1512 is greater than the length of the pole 152, so as to avoid the pole 152 protruding from the top cover 151 in the Z direction, thereby reducing the consumption of the longitudinal dimension of the battery cell 12 by the pole 152, improving the space utilization of the battery cell 14 to the battery 10, and thus improving the energy density of the battery 10 composed of multiple battery cells 12.

[0100] In some embodiments, as shown in FIG. 8 , the length of the first bending section 1512 along the Y direction is L2 , and the length of the pole 152 along the Y direction is L3 , satisfying: 1<L2 / L3≤2.

[0101] Among them, the ratio of L2 to L3 can be 1.5, 1.8, 1.9 or 2, that is, the length of the first bending section 1512 along the Y direction is greater than the length of the pole 152 along the Y direction, so as to avoid the pole 152 protruding from the first bending section 1512 in the Y direction, thereby reducing the distance between adjacent battery cells 12, and further improving the energy density of the battery 10 composed of multiple battery cells 12.

[0102] In some embodiments, as shown in FIG. 9 , the length of the top cover 151 along the X direction is L0 , and the length of the second bending section 1513 protruding from the first bending section 1512 along the X direction is H2 , satisfying: 1%≤H2 / L0≤10%.

[0103] Among them, the ratio of H2 to L0 can be 1%, 2.5%, 5%, 7%, 9% or 10%. By limiting the ratio range of the length H2 of the second bending section 1513 protruding from the first bending section 1512 along the X direction to the length L0 of the top cover 151 along the X direction, while meeting the installation space of the pole 152, the lateral space consumption of the battery cell 12 can be reduced, the space utilization rate of the battery cell 14 to the battery cell 12 is improved, and the energy density of the battery cell 12 is improved.

[0104] According to some embodiments of the present application, as shown in FIG. 11 and FIG. 13 , the present application further provides a pole piece 141 , comprising: a pole piece body 1411 and a pole ear 142 .

[0105] The pole piece main body 1411 includes a first part 14111 and a second part 14112 connected along the Z direction. The length of the first part 14111 along the X direction is smaller than the length of the second part 14112 along the X direction. The first part 14111 is formed with a notch, which is used to avoid the first bending section 1512; the pole ear 142 is connected to the side of the first part 14111 away from the second part 14112.

[0106] The gap formed by the first portion 14111 is used to avoid the first bending section 1512 and the second bending section 1513 of the top cover 151 so that the electrode 141 and the top cover 151 can be matched to increase the space utilization of the battery cell 14 to the battery 10 .

[0107] By connecting the pole ear 142 to the side of the first part 14111 away from the second part 14112, the pole ear 142 extends along the Z direction, and the consumed space of the pole ear 142 and the consumed space of the pole column 152 are located on different sides of the battery cell 12. Compared with setting the pole ear 142 and the pole column 152 on the same side of the pole piece 141, the space consumption of the pole ear 142 and the pole column 152 on the battery cell 12 can be saved, and the space utilization rate of the battery cell 14 to the battery cell 12 can be improved, thereby improving the energy density of the battery cell 12.

[0108] The pole piece 141 provided in the embodiment of the present application can cooperate with the top cover 151 by designing a notch. Compared with the design scheme of poles outputting from the same side or from the opposite side, on the one hand, the present application can fully utilize the lateral space of the battery cell 12 in the X direction and reduce the consumption of the longitudinal dimension of the battery cell 12 in the Z direction. When the size of the battery cell 12 is fixed, the volume of the battery cell 14 of the battery cell 12 is increased, and the space utilization rate of the battery cell 14 to the battery cell 12 is improved, thereby improving the energy density of the battery cell 12. On the other hand, the two poles 152 are respectively arranged on both sides of the battery cell 12 in the X direction, and the adjacent battery cells 12 can be welded together by butt welding the poles 152. Compared with the scheme in which the two poles 152 extend in the same direction and require the use of a busbar or adapter to connect the two battery cells 12 together, the use of a busbar or adapter is reduced and the occupied space is reduced, and the space consumption of the battery cell is reduced. Butt welding saves more welding space, improves the space utilization rate of the battery cell 14 to the battery 10, and thus improves the energy density of the battery 10 composed of multiple battery cells 12.

[0109] In some embodiments, as shown in Figures 10 and 11, the electrode sheet 141 is applied to the laminated battery cell 14, and the notches are provided at both ends of the first part 14111 in the X direction. The distance from the electrode tab 142 to one of the notches is smaller than the distance to the other notch, so that when the positive electrode sheet and the negative electrode sheet are stacked together, there is a gap between the positive electrode tab and the negative electrode tab.

[0110] The electrode 141 may be a positive electrode or a negative electrode.

[0111] In some embodiments, as shown in Figures 12 and 13, a pole piece 141 is applied to a wound-type battery cell 14. Multiple notches divide the first portion 14111 into multiple segments, each segment having a tab 142. The pole piece 141 includes multiple sub-pole pieces connected along the X direction. The second portions 14112 of two adjacent sub-pole pieces are connected, and the first portions 14111 of two adjacent sub-pole pieces are separated by a notch. The distance from the pole piece 141 to one of the two adjacent notches is smaller than the distance to the other. This ensures that when the positive and negative pole pieces are wound together, there is a gap between the positive and negative tabs.

[0112] The electrode 141 may be a positive electrode or a negative electrode.

[0113] According to some embodiments of the present application, as shown in Figures 10 and 12, the present application also provides a battery cell 14, which includes: a diaphragm and a pole piece 141 such as any one of the above embodiments; the pole piece 141 includes a positive pole piece and a negative pole piece; the diaphragm is located between the pole piece main body 1411 of the positive pole piece and the negative pole piece.

[0114] The battery cell 14 provided in the embodiment of the present application can be matched with the bent top cover 151 by adopting a pole piece 141 with a notch. Compared with the design scheme of the poles output on the same side or the poles output on the opposite sides, on the one hand, the present application can make full use of the lateral space of the battery cell 12 and reduce the longitudinal space consumption of the battery cell 12. When the size of the battery cell 12 is fixed, the volume of the battery cell 14 of the battery cell 12 is increased, and the space utilization rate of the battery cell 14 to the battery cell 12 is improved, thereby improving the energy density of the battery cell 12; on the other hand, the two poles 152 are respectively arranged on both sides of the battery cell 12, and the adjacent battery cells 12 can be welded together by butt welding the poles 152. Compared with the scheme in which the two poles 152 extend in the same direction and a busbar or adapter is required to connect the two battery cells 12 together, butt welding saves more welding space, improves the space utilization rate of the battery cell 14 to the battery 10, and thus improves the energy density of the battery 10 composed of multiple battery cells 12.

[0115] In some embodiments, as shown in Figures 10 and 12, the positive electrode tab of the positive electrode sheet and the negative electrode tab of the negative electrode sheet are located on the same side. After the positive electrode sheet and the negative electrode sheet are stacked to form the battery cell 14, the positive electrode tab and the negative electrode tab are located on the same side of the battery cell 14. Compared with the structure in which the positive electrode tab and the negative electrode tab are located on different sides of the battery cell 14, the space consumption of the battery cell 12 can be reduced, and the space utilization rate of the battery cell 14 to the battery cell 12 can be improved, thereby improving the energy density of the battery cell 12.

[0116] According to some embodiments of the present application, the present application provides a battery cell 12 .

[0117] The battery cell 12 includes a housing 13 , a battery cell 14 and a top cover assembly 15 in any of the above embodiments. The battery cell 14 is disposed in the housing 13 , and the top cover assembly 15 is installed in the opening 131 .

[0118] The battery cell 14 is formed by the electrode piece 141 in any of the above embodiments.

[0119] In the above technical solution, the outer contour of any of the above-mentioned battery cells 14 is adapted to the outer contour of the top cover assembly 15, which can make full use of the lateral space of the battery cell 12 and reduce the space consumption of the battery cell 12. When the size of the battery cell 12 is fixed, the volume of the battery cell 14 of the battery cell 12 is increased, and the space utilization rate of the battery cell 14 to the battery cell 12 is improved, thereby improving the energy density of the battery cell 12.

[0120] The top cover 151 provided in any of the above embodiments is designed to be bent, and the poles 152 extend in different directions. Compared with the design scheme in which the two poles 152 extend in the same direction, on the one hand, the present application can make full use of the lateral space of the battery cell 12 and reduce the space consumption of the battery cell 12. When the size of the battery cell 12 is fixed, the volume of the battery cell 14 of the battery cell 12 is increased, and the space utilization rate of the battery cell 14 to the battery cell 12 is improved, thereby improving the energy density of the battery cell 12; on the other hand, when the battery cells are grouped, the poles of adjacent battery cells can be butt-welded, thereby reducing the use and occupied space of the bars or buses, reducing the space consumption of the battery cells, and improving the space utilization rate of the battery cells to the battery cells, thereby improving the energy density of the battery 10 composed of multiple battery cells 12.

[0121] In some embodiments, the positive tab and the negative tab of the battery cell 14 are located on the same side.

[0122] Among them, the lateral projection of the positive electrode tab and the negative electrode tab along the battery cell 12 has an overlapping part with the lateral projection of the first bending section 1512 along the battery cell 12, that is, the space consumed by the tab 142 and the space consumed by the pole 152 are combined together, which reduces the space consumption of the battery cell 12. When the size of the battery cell 12 is fixed, the volume of the battery cell 14 of the battery cell 12 is increased, and the space utilization rate of the battery cell 14 to the battery cell 12 is improved, thereby improving the energy density of the battery cell 12.

[0123] In some embodiments, as shown in FIG. 4 , the electrode terminal further includes: a transition piece 16 , which includes a first section 161 and a second section 162 that are connected and relatively bent, wherein the first section 161 is connected to the pole 152 , and the second section 162 is connected to the tab 142 .

[0124] The adapter 16 is disposed between the top cover 151 and the battery cell 14. There are two adapters 16, one of which is used to connect one of the poles 152 and the positive electrode tab, and the other is used to connect the other pole 152 and the negative electrode tab.

[0125] Among them, the battery core 14 can be a laminated type or a wound type. The laminated structure has a higher energy density, and the wound structure has a faster production speed.

[0126] In some embodiments, as shown in FIG. 5 , the length of the battery cell 12 along the X direction is L4 , which satisfies: 100 mm ≤ L4 ≤ 400 mm.

[0127] Among them, L4 of the battery cell 12 can be 100 mm, 200 mm, 250 mm, 300 mm or 400 mm.

[0128] It should be noted that, as shown in FIG16 , in the battery cell in the related art in which the tab and the pole are located on the same side of the battery cell, when the length of the battery cell is less than 400 mm, the space consumed by the tab and the pole in the Z direction is very large, thereby increasing the proportion of the space consumed by the tab and the pole in the total space of the battery cell. That is, the battery cell solution in the related art is not advantageous when the length of the battery cell along the X direction is less than 400 mm.

[0129] The present application provides a battery cell 12. Since the tab 142 and the pole 152 are located on different sides of the battery cell 12, and the positive tab and the negative tab are located on the same side of the battery cell 12, when the length of the battery cell 12 along the X direction is less than 400 mm, the space consumed by the tab 142 and the space consumed by the pole 152 can be effectively reduced. When the size of the battery cell 12 is less than 400 mm, the space utilization rate of the battery cell 14 to the battery cell 12 is improved, thereby improving the energy density of the battery cell 12.

[0130] The fixed battery cell 12 size and the different terminal 152 installation positions are compared. The battery cell 12 structure with the terminal 152 facing both sides is shown in FIG15 , the battery cell 12 structure with the terminal 152 on the same side is shown in FIG16 , and the battery cell 12 structure with the terminal 152 on the opposite side is shown in FIG17 . The space utilization of the battery cell 12 is calculated, and the data in Table 1 below is obtained:

[0131] Table 1

[0132] As shown in Table 1, in the first set of comparative data with a battery cell size of 100 mm * 150 mm * 30 mm, as shown in FIG15 , in Example 1, the pole consumption space V1 only occupies a portion of the battery cell along the X direction, and the battery cell space utilization rate is 81.72%; as shown in FIG16 , in the battery cell with poles on the same side in Comparative Example 1, the pole consumption space V1 and the tab consumption space V2 jointly occupy the top of the battery cell, and the occupied length is at least the total length of the pole and the tab along the Z direction, and the battery cell space utilization rate is 80.96%; as shown in FIG17 , in the battery cell with poles on the opposite sides in Comparative Example 2, the pole consumption space V1 and the tab consumption space V2 jointly occupy both ends of the battery cell along the X direction, and the occupied length of both ends is at least the total length of the pole and the tab along the X direction, and the battery cell space utilization rate is 63.80%. It can be seen that in the first set of comparative data with a battery cell size of 100 mm * 150 mm * 30 mm, the battery cell with poles facing both sides has the highest battery cell space utilization rate.

[0133] In the second set of comparative data with a battery cell size of 200mm*150mm*30mm, as shown in FIG15 , in Example 2, the pole consumption space V1 only occupies a portion of the battery cell along the X direction, and the battery cell space utilization rate is 86.59%; as shown in FIG16 , in the battery cell with poles on the same side in Comparative Example 3, the pole consumption space V1 and the tab consumption space V2 jointly occupy the top of the battery cell, and the occupied length is at least the total length of the pole and the tab along the Z direction, and the battery cell space utilization rate is 85.78%; as shown in FIG17 , in the battery cell with poles on the opposite side in Comparative Example 4, the pole consumption space V1 and the tab consumption space V2 jointly occupy both ends of the battery cell along the X direction, and the occupied length of both ends is at least the total length of the pole and the tab along the X direction, and the battery cell space utilization rate is 81.90%. It can be seen that in the first set of comparative data with a battery cell size of 200mm*150mm*30mm, the battery cell with poles facing both sides has the highest battery cell space utilization rate.

[0134] In the third set of comparative data with a battery cell size of 300mm*150mm*30mm, as shown in FIG15 , in Example 3, the pole consumption space V1 only occupies a portion of the battery cell along the X direction, and the battery cell space utilization rate is 88.21%. As shown in FIG16 , in the battery cell with poles on the same side in Comparative Example 5, the pole consumption space V1 and the tab consumption space V2 jointly occupy the top of the battery cell, and the occupied length is at least the total length of the pole and the tab along the Z direction, and the battery cell space utilization rate is 87.39%. As shown in FIG17 , in the battery cell with poles on the opposite side in Comparative Example 6, the pole consumption space V1 and the tab consumption space V2 jointly occupy both ends of the battery cell in the longitudinal direction, and the occupied length of both ends is at least the total length of the pole and the tab along the X direction, and the battery cell space utilization rate is 87.93%. It can be seen that in the first set of comparative data with a battery cell size of 300mm*150mm*30mm, the battery cell with poles facing both sides has the highest battery cell space utilization rate.

[0135] In summary, the space utilization rates of the battery cells 12 with the poles 152 facing both sides are greater than the space utilization rates of the battery cells 12 with the poles facing the same side or facing the opposite sides.

[0136] According to some embodiments of the present application, the present application further provides a battery 10 , which includes: a plurality of battery cells 12 as described above.

[0137] Any of the above-mentioned battery cells 12 has a high energy density, and thus the battery 10 including the battery cell 12 has a high energy density.

[0138] In some embodiments, the poles 152 of at least two adjacent battery cells 12 are arranged relative to each other and connected to each other, so that at least two adjacent battery cells 12 do not need to be welded using a bus bar or adapter plate, saving welding space, improving the space utilization of the battery cell 14 to the battery 10, and thus improving the energy density of the battery 10 composed of multiple battery cells 12.

[0139] According to some embodiments of the present application, the present application further provides an electrical device, comprising: a battery 10 as described above, the battery 10 being used to provide electrical energy to the electrical device.

[0140] The battery 10 has a high energy density, so the electrical device including the battery 10 has a long battery life.

[0141] It should be noted that, unless there is any conflict, the embodiments and features in the embodiments of this application can be combined with each other.

[0142] The above are merely preferred embodiments of the present application and are not intended to limit the present application. Those skilled in the art will readily appreciate that various modifications and variations are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present application shall be included within the scope of protection of the present application.

Claims

1. A top cover assembly, characterized in that: Applied to a battery, the top cover assembly includes: A top cover, comprising a top cover main body and a first bent section, wherein both ends of the top cover main body are connected to the first bent section bent relative to the top cover main body; The electrode terminal includes an electrode post, and the electrode post is installed in the first bending section.

2. The top cover assembly according to claim 1, wherein: One end of the pole is connected to the first bending section, a transverse projection of the pole along the X direction falls within a transverse projection of the first bending section along the X direction, and an outer contour of the transverse projection of the pole along the X direction is spaced apart from an outer contour of the transverse projection of the first bending section along the X direction.

3. The top cover assembly according to claim 1 or 2, characterized in that: The top cover further includes a second bending section connected to an end of the first bending section away from the top cover main body. The second bending section is bent relative to the first bending section and extends in a direction away from the top cover main body.

4. The top cover assembly according to claim 3, wherein: The length of the pole protruding from the first bending section along the X direction is greater than or equal to the length of the second bending section protruding from the first bending section along the X direction.

5. The top cover assembly according to claim 4, wherein: The length of the pole protruding from the first bending section along the X direction is H1, and the length of the second bending section protruding from the first bending section along the X direction is H2, satisfying: 0mm<H1-H2≤3mm.

6. The top cover assembly according to any one of claims 3 to 5, characterized in that: The length of the top cover along the X direction is L0, and the length of the second bending section protruding from the first bending section along the X direction is H2, satisfying the following: 1%≤H2 / L0≤10%.

7. The top cover assembly according to any one of claims 1 to 6, characterized in that: The length of the first bending section along the Z direction is H3, and the length of the pole along the Z direction is L1, which satisfies the following: 1<H3 / L1≤4.

8. The top cover assembly according to any one of claims 1 to 7, characterized in that: The length of the first bending section along the Y direction is L2, and the length of the pole along the Y direction is L3, which satisfies the following: 1<L2 / L3≤2.

9. A pole piece, characterized in that: include: a pole piece main body, the pole piece main body comprising a first portion and a second portion connected along the Z direction, the length of the first portion along the X direction being smaller than the length of the second portion along the X direction, and a notch formed in the first portion, the notch being used to avoid the first bending section; A tab is connected to a side of the first portion facing away from the second portion.

10. The pole piece according to claim 9, applied to a laminated battery cell, characterized in that: The notches are provided at both ends of the first portion in the X direction, and the distance from the tab to one of the notches is smaller than the distance to the other notch.

11. The pole piece according to claim 9, applied to a wound-type battery cell, characterized in that: The plurality of notches divide the first part into multiple sections, each section is provided with the pole ear, the pole piece includes a plurality of sub-pole pieces connected along the X direction, the second parts of two adjacent sub-pole pieces are connected, the first parts of two adjacent sub-pole pieces are separated by the notch, and the distance from the pole ear to one of the two adjacent notches is less than the distance to the other.

12. A battery cell, characterized in that: include: a housing, the housing being formed with an opening; a battery cell, disposed in the housing; The top cover assembly according to any one of claims 1 to 8, wherein the top cover assembly is mounted on the opening.

13. The battery cell according to claim 12, characterized in that: The positive electrode tab and the negative electrode tab of the battery cell are located on the same side.

14. The battery cell according to claim 13, characterized in that The electrode terminal further includes a transition piece, which includes a first section and a second section that are connected and bent relative to each other, wherein the first section is connected to the electrode column, and the second section is connected to the electrode tab.

15. The battery cell according to any one of claims 12 to 14, characterized in that: The battery core is of laminated type or wound type.

16. The battery cell according to any one of claims 12 to 15, characterized in that: The length of the battery cell along the X direction is L4, which satisfies: 100 mm ≤ L4 ≤ 400 mm.

17. A battery, characterized in that: include: A plurality of battery cells according to any one of claims 12 to 16.

18. The battery according to claim 17, characterized in that The poles of at least two adjacent battery cells are arranged opposite to each other and butted against each other.

19. An electrical device, characterized in that: include: The battery according to claim 17 or 18, wherein the battery is used to provide electrical energy to the electrical device.

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