Battery monomer, battery and electric device

Abstract

The utility model provides a battery monomer, a battery and a power utilization device. The battery monomer comprises a top cover assembly, an electrode assembly and a switching mechanism, electrode terminals are arranged on the top cover assembly, each electrode terminal comprises more than two pole columns arranged at intervals, the electrode assembly comprises tabs, the switching mechanism is arranged between the top cover assembly and the electrode assembly, the switching mechanism comprises a first connecting part and a second connecting part which are connected with each other, and the first connecting part and the second connecting part are connected with each other. The second connecting part is connected to a tab of the electrode assembly, the first connecting part comprises more than two sub-connecting parts which are arranged at intervals, and each sub-connecting part is correspondingly connected with each pole, so that the electrode terminal can be electrically connected with the electrode assembly through the first connecting part and the second connecting part, and the more than two sub-connecting parts are arranged on the switching mechanism at intervals; therefore, the switching mechanism can be fully connected with each pole of the terminal, the connection area of the pole and the switching mechanism is increased, the overcurrent capability between the electrode terminal and the switching mechanism is improved, and the overall overcurrent performance of the battery is improved.

Description

Technical Field

[0001] The present application relates to the field of batteries, and in particular to a battery cell, a battery and an electrical device. Background Art

[0002] Energy conservation and emission reduction are the key to the sustainable development of the automobile industry. Electric vehicles have become an important part of the sustainable development of the automobile industry due to their advantages of energy conservation and environmental protection. For electric vehicles, battery technology is an important factor related to their development.

[0003] How to improve the current carrying capacity of battery cells is an important research direction in battery technology. Utility Model Content

[0004] In view of the above problems, the present application provides a battery cell, a battery and an electrical device, which can improve the current carrying capacity of the battery cell.

[0005] In a first aspect, the present application provides a battery cell, comprising: a top cover assembly, on which an electrode terminal is arranged; an electrode assembly, including a pole lug; a switching mechanism, arranged between the top cover assembly and the electrode assembly, wherein each electrode terminal comprises two or more poles arranged at intervals, the switching mechanism comprises a first connecting portion and a second connecting portion connected to each other, the first connecting portion comprises two or more sub-connecting portions arranged at intervals, each sub-connecting portion is respectively connected to each pole, and the second connecting portion is connected to the pole lug.

[0006] In the scheme of the embodiment of the present application, the battery cell includes a top cover assembly, an electrode assembly and an adapter mechanism, the top cover assembly is provided with an electrode terminal, each electrode terminal includes two or more poles arranged at intervals, the electrode assembly includes a pole ear, the adapter mechanism is arranged between the top cover assembly and the electrode assembly, the adapter mechanism includes a first connecting portion and a second connecting portion connected to each other, the second connecting portion is connected to the pole ear of the electrode assembly, the first connecting portion includes two or more sub-connecting portions arranged at intervals, each sub-connecting portion and each pole is correspondingly connected, so that the electrode terminal can be electrically connected to the electrode assembly through the first connecting portion and the second connecting portion, thereby by arranging more than two sub-connecting portions at intervals on the adapter mechanism, so that the adapter mechanism can be fully connected to each pole of the terminal, thereby increasing the connection area between the pole and the adapter mechanism, thereby increasing the current carrying capacity between the electrode terminal and the adapter mechanism, thereby improving the overall current carrying performance of the battery.

[0007] In some embodiments, the second connecting portion includes an extension segment and a bending segment that are connected to each other. In the first direction, the bending segment is located between the two extension segments. The extension segment is connected to the sub-connecting portion. The bending segment is formed by bending a portion of the second connecting portion so that the second connecting portion can be deformed in the first direction.

[0008] In the technical solution of the embodiment of the present application, the second connecting part includes an extension section and a bending section that are connected to each other. The bending section is located between the two extension sections. The extension section is connected to the sub-connecting part. The bending section is formed by bending part of the second connecting part, so that during the connection process between the first connecting part and the pole, the bending section can be deformed in the first direction, so as to improve the extensibility of the adapter mechanism in the first direction through the bending section, so as to reduce the risk of breakage of the adapter mechanism under the action of the connection stress.

[0009] In some embodiments, the electrode tab includes a welding region, the electrode tab is connected to the second connecting portion at the welding region, and the welding region and the bending section are alternately arranged.

[0010] In the technical solution of the embodiment of the present application, the pole ear includes a welding area, the pole ear is connected to the second connecting portion in the welding area, and the welding area and the bending section are staggered to reduce the influence of the bending section on the connection effect of the switching mechanism and the pole ear.

[0011] In some embodiments, the bent section is formed by bending a portion of the second connecting portion toward the top cover assembly.

[0012] In the technical solution of the embodiment of the present application, the bent section is formed by bending part of the second connecting portion toward the top cover assembly to reduce the risk of the bent section damaging the tab.

[0013] In some embodiments, the sub-connection part is respectively provided with a first connection area and a second connection area on both side surfaces in the thickness direction thereof, the pole is connected to the sub-connection part in the first connection area, embossing is provided in the second connection area, and the projection of the first connection area in the thickness direction of the sub-connection part and the projection of the second connection area in the thickness direction at least partially overlap.

[0014] In the technical solution of the embodiment of the present application, the sub-connection part is respectively provided with a first connection area and a second connection area on the two side surfaces in the thickness direction thereof, the projection of the first connection area in the thickness direction of the sub-connection part and the projection of the second connection area in the thickness direction at least partially overlap, the pole is connected to the sub-connection part in the first connection area, and embossing is provided in the second connection area, so that during the welding process of the pole and the adapter mechanism, the embossing of the second connection area can reduce the attenuation of laser energy, so as to improve the welding effect of the pole and the adapter laser.

[0015] In some embodiments, the electrode tab includes two sub-tabs arranged opposite to each other along the thickness direction of the electrode assembly, the switching mechanism includes two second connecting parts arranged opposite to each other along the thickness direction of the electrode assembly, the first connecting part is connected between the two second connecting parts, and the two second connecting parts are respectively connected to the two sub-tabs.

[0016] In the technical solution of the embodiment of the present application, the pole ear includes two sub-pole ears arranged opposite to each other along the thickness direction of the electrode assembly, and the adapter mechanism includes two second connecting parts arranged opposite to each other along the thickness direction of the electrode assembly, so that the second connecting parts are stably connected to the sub-pole ears respectively, and the first connecting part is connected between the two second connecting parts, so that during the connection process between the second connecting part and the pole ear, the forces on both sides of the first connecting part are balanced, and it will not cause excessive misalignment, thereby reducing the difficulty of connecting the pole column and the first connecting part; and the first connecting part is connected between the two second connecting parts, which also helps to improve the overall stability of the adapter mechanism; and because the first connecting part is located between the two sub-pole ears, the first connecting part will not limit the extension length of the sub-pole ear, and the extension size of the sub-pole ear can be more conveniently designed to improve the overcurrent performance of the battery cell.

[0017] In some embodiments, the sub-connecting portion includes a bottom wall and a side wall, one end of the side wall is connected to the second connecting portion, the other end of the side wall extends away from the top cover assembly and is connected to the bottom wall, and the pole is connected to the bottom wall.

[0018] In the technical solution of the embodiment of the present application, the sub-connecting part includes a bottom wall and a side wall, one end of the side wall is connected to the second connecting part, the other end of the side wall extends away from the top cover assembly and is connected to the bottom wall, the pole is connected to the bottom wall, and the bottom wall and the side wall form a groove for avoiding the pole. At the same time, this avoidance groove can also provide a positioning function during the welding process of the adapter mechanism and the pole, so as to reduce the difficulty of connecting the top cover assembly and the adapter mechanism.

[0019] In some embodiments, two adjacent sub-connection portions and two second connection portions enclose a hollow area.

[0020] In the technical solution of the embodiment of the present application, two adjacent sub-connecting parts and two second connecting parts enclose a hollow area, and the hollow area can reduce the dead weight of the switching mechanism and save the material cost of the switching mechanism.

[0021] In some embodiments, the top cover assembly includes a first terminal and a second terminal with opposite polarities, and the battery cell also includes an overcharge protection mechanism, which is connected to the top cover assembly and arranged between the top cover assembly and the adapter mechanism. The overcharge protection mechanism at least partially overlaps with the positive projection and the hollow area of ​​the adapter mechanism. The overcharge protection mechanism is configured such that when the internal pressure of the battery cell reaches a first threshold, the pressure acts on the overcharge protection mechanism through the through hole, and the first terminal and the second terminal are electrically connected through the overcharge protection mechanism.

[0022] In the technical solution of the embodiment of the present application, the battery cell also includes an overcharge protection mechanism, which is arranged between the top cover assembly and the adapter mechanism. The overcharge protection mechanism at least partially overlaps with the orthographic projection and the hollow area of ​​the adapter mechanism. The overcharge protection mechanism is configured to connect the first terminal and the second terminal when the internal pressure of the battery cell reaches a first threshold value, so as to short-circuit the external power supply circuit of the battery cell and reduce the risk of thermal runaway of the battery cell; and by arranging the overcharge protection mechanism between the hollow area and the top cover assembly, the internal pressure of the battery cell can act on the overcharge protection mechanism through the hollow area. The hollow area has the effect of reducing the deadweight of the adapter mechanism, and can be reused as a pressure channel between the overcharge protection mechanism and the internal environment of the battery cell, which reflects the efficient use of the internal space of the battery by the adapter mechanism provided in this embodiment.

[0023] In some embodiments, the second connecting part of the transfer mechanism includes a substrate and a weakened section connected to the substrate, the substrate is connected to the pole ear, the weakened section is connected to the substrate and the sub-connecting part, and along the arrangement direction of the first connecting part and the second connecting part, the cross-sectional area of ​​the weakened section is smaller than the cross-sectional area of ​​the sub-connecting part.

[0024] In the technical solution of the embodiment of the present application, the second connecting part of the adapter mechanism includes a substrate and a weakened section connected to the substrate, the substrate is connected to the pole ear, the weakened section is connected to the substrate and the sub-connecting part, and along the arrangement direction of the first connecting part and the second connecting part, the cross-sectional area of ​​the weakened section is smaller than the cross-sectional area of ​​the sub-connecting part, so that when the overcharge protection mechanism connects the first terminal and the second terminal, the high temperature generated by the short circuit between the first terminal and the second terminal can melt the weakened section, so as to disconnect the electrode terminal and the electrode assembly, further reduce the risk of thermal runaway of the battery cell, and improve the reliability of the battery cell.

[0025] In some embodiments, the transition mechanism includes a first transition mechanism and a second transition mechanism, the first transition mechanism is connected to the first terminal, the second transition mechanism is connected to the second terminal, the melting point of the first transition mechanism is lower than the melting point of the second transition mechanism, and the weakened section is arranged on the first transition mechanism.

[0026] In the technical solution of the embodiment of the present application, the adapter mechanism includes a first adapter mechanism and a second adapter mechanism. The first adapter mechanism is connected to the first terminal, and the second adapter mechanism is connected to the second terminal. The melting point of the first adapter mechanism is lower than the melting point of the second adapter mechanism. The weakened section is arranged on the first adapter mechanism to facilitate the melting of the weakened section of the first adapter mechanism under high temperature conditions. In addition, the weakened section is processed on the first adapter mechanism, which reduces the processing difficulty of the second adapter mechanism and helps to improve the overall processing efficiency of the adapter mechanism.

[0027] In a second aspect, the present application provides a battery, comprising a battery cell according to any one of the embodiments of the first aspect.

[0028] In a third aspect, the present application provides an electrical device, comprising the battery of the above-mentioned second aspect embodiment. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present application. Also, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:

[0030] Figure 1 is a structural schematic diagram of a vehicle provided by an embodiment of the present application;

[0031] Figure 2 is a schematic diagram of the structure of a battery provided in one embodiment of the present application;

[0032] Figure 3 is a schematic structural diagram of a battery module provided in one embodiment of the application;

[0033] Figure 4 is an exploded diagram of a battery cell provided in one embodiment of the present application;

[0034] Figure 5 is an exploded diagram of a battery cell provided in one embodiment of the present application;

[0035] Figure 6 It is a structural schematic diagram of a switching mechanism of a battery cell provided in one embodiment of the present application;

[0036] Figure 7 is a side view of a switching mechanism of a battery cell provided in one embodiment of the present application;

[0037] Figure 8 is a schematic diagram of an expanded battery cell provided by an embodiment of the present application;

[0038] Fig. 9 is a top view of a switching mechanism of a battery cell provided in one embodiment of the present application;

[0039] Fig.10 It is a structural schematic diagram of a switching mechanism of a battery cell provided in one embodiment of the present application;

[0040] Fig.11 It is a partial structural schematic diagram of a battery cell provided in one embodiment of the present application;

[0041] Fig.12 yes Fig.11 Sectional view at AA in the middle;

[0042] Fig.13 yes Fig.12 Schematic diagram of the enlarged structure at point B in the middle.

[0043] Description of reference numerals:

[0044] 1. Vehicle; 101. Motor; 102. Controller;

[0045] 2. Battery; 201. Battery module; 202. Box; 2021. First box portion; 2022. Second box portion; 3. Battery cell; 4. Shell;

[0046] 5. electrode assembly; 6. top cover assembly; 61. electrode terminal; 51. pole ear; 62. pole column; 511. sub-pole ear; 611. first terminal; 612. second terminal; 512. welding area; 52. electrode body;

[0047] 7. Transfer mechanism; 71. First connection part; 72. Second connection part; 711. Sub-connection part; 721. Extension section; 722. Bend section; 7111. First connection area; 7112. Second connection area; 7113. Bottom wall; 7114. Side wall; 74. Hollow area; 723. Base sheet; 724. Weakened section; 75. First transfer mechanism; 76. Second transfer mechanism;

[0048] 8. Overcharge protection mechanism; 81. Flip sheet. DETAILED DESCRIPTION

[0049] The following embodiments of the technical solution of the present application are described in detail in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application, and are therefore only used as examples, and cannot be used to limit the scope of protection of the present application.

[0050] It should be noted that, unless otherwise specified, the technical terms or scientific terms used in the embodiments of the present application should have the common meanings understood by technicians in the field to which the embodiments of the present application belong.

[0051] In the description of the embodiments of the present application, the orientations or positional relationships indicated by technical terms such as "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", and "circumferential" are based on the orientations or positional relationships shown in the accompanying drawings and 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 referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the embodiments of the present application.

[0052] In addition, the technical terms "first", "second", etc. are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. In the description of the embodiments of the present application, the meaning of "multiple" is more than two, unless otherwise clearly and specifically defined.

[0053] In the description of the embodiments of the present application, unless otherwise clearly specified and limited, technical terms such as "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0054] In the description of the embodiments of the present application, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0055] At present, from the perspective of market development, the application of power batteries is becoming more and more extensive. Power batteries are not only used in energy storage power systems such as hydropower, thermal power, wind power and solar power stations, but also widely used in electric vehicles such as electric bicycles, electric motorcycles, electric cars, as well as military equipment and aerospace and other fields. With the continuous expansion of the application field of power batteries, the market demand is also constantly expanding.

[0056] In the present application, the battery cell may include a lithium-ion secondary battery cell, a lithium-ion primary battery cell, a lithium-sulfur battery cell, a sodium-lithium-ion battery cell, a sodium-ion battery cell or a magnesium-ion battery cell, etc., and the embodiments of the present application do not limit this. The battery cell may be cylindrical, flat, rectangular or other shapes, etc., and the embodiments of the present application do not limit this.

[0057] The battery mentioned in the embodiments of the present application refers to a single physical module including one or more battery cells to provide higher voltage and capacity. For example, the battery mentioned in the present application may include a battery module or a battery pack. The battery generally includes a box for encapsulating one or more battery cells. The box can prevent liquid or other foreign matter from affecting the charging or discharging of the battery cells.

[0058] A battery cell includes an electrode assembly and an electrolyte. The electrode assembly includes a positive electrode sheet, a negative electrode sheet and a separator. A battery cell mainly works by the movement of metal ions between the positive electrode sheet and the negative electrode sheet. 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 current collector. The positive current collector includes a positive current collector and a positive electrode ear connected to the positive current collector. The positive current collector is coated with a positive active material layer, and the positive electrode ear is not coated with a positive active material layer. Taking a lithium-ion battery as an example, the material of the positive current collector can be aluminum, and the positive active material layer includes a positive active material. The positive active material can be lithium cobalt oxide, lithium iron phosphate, ternary lithium or lithium manganese oxide, etc. 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 current collector; the negative current collector includes a negative current collector and a negative electrode tab connected to the negative current collector, the negative current collector is coated with the negative active material layer, and the negative electrode tab is not coated with the negative active material layer. The material of the negative current collector can be copper, the negative active material layer includes a negative active material, and the negative active material can be carbon or silicon, etc. The material of the separator can be PP (polypropylene) or PE (polyethylene), etc.

[0059] In the prior art, the current carrying capacity of battery cells still needs to be improved.

[0060] In the related technology, the charging and discharging of the electrode assembly is achieved through a series of structures including the pole ear, the adapter mechanism and the pole column. The size of the series of mechanisms themselves, the connection area between the pole column and the adapter mechanism, the connection area between the adapter mechanism and the pole ear and other factors all affect the overall overcurrent effect of the battery cell.

[0061] Based on the above problems, the battery cell includes a top cover assembly, an electrode assembly and a switching mechanism, the top cover assembly is provided with an electrode terminal, the electrode terminal includes two or more poles arranged at intervals, the electrode assembly includes a pole ear, the switching mechanism is arranged between the top cover assembly and the electrode assembly, the switching mechanism includes a first connecting portion and a second connecting portion connected to each other, the second connecting portion is connected to the pole ear of the electrode assembly, the first connecting portion includes two or more sub-connecting portions arranged at intervals, each sub-connecting portion and each pole is correspondingly connected, so that the electrode terminal can be electrically connected to the electrode assembly through the first connecting portion and the second connecting portion, thereby by arranging more than two sub-connecting portions at intervals on the switching mechanism, the switching mechanism can be fully connected to each pole of the terminal, thereby increasing the connection area between the pole and the switching mechanism, thereby increasing the current carrying capacity between the electrode terminal and the switching mechanism, thereby improving the overall current carrying performance of the battery.

[0062] The technical solutions described in the embodiments of the present application are applicable to batteries and electrical devices using batteries.

[0063] The electrical device may be a vehicle, a mobile phone, a portable device, a laptop computer, a ship, a spacecraft, an electric toy, an electric tool, and the like. The vehicle may be a fuel vehicle, a gas vehicle, or a new energy vehicle, and the new energy vehicle may be a pure electric vehicle, a hybrid vehicle, or an extended-range vehicle, and the like; the spacecraft may include an airplane, a rocket, a space shuttle, and a spacecraft, and the like; 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, and the like; the electric tool may include a metal cutting electric tool, a grinding electric tool, an assembly electric tool, and an electric tool for railways, such as an electric drill, an electric grinder, an electric wrench, an electric screwdriver, an electric hammer, an impact drill, a concrete vibrator, and an electric planer, and the like. The embodiments of the present application do not impose any special restrictions on the above-mentioned electrical devices.

[0064] It should be understood that the technical solutions described in the embodiments of the present application are not limited to the batteries and electrical equipment described above, but can also be applied to all batteries including a box and electrical equipment using the battery. However, for the sake of simplicity, the following embodiments are described using electric vehicles as an example.

[0065] Please refer to Figure 1 , Figure 1 A schematic diagram of the structure of a vehicle 1 provided for some embodiments of the present application. Vehicle 1 may be a fuel vehicle, a gas vehicle or a new energy vehicle, and the new energy vehicle may be a pure electric vehicle, a hybrid vehicle or an extended-range vehicle, etc. A battery 2 is provided inside the vehicle 1, and the battery may be provided at the bottom, head or tail of the vehicle 1. Battery 2 may be used to power the vehicle 1, for example, battery 2 may be used as an operating power source for the vehicle 1. Vehicle 1 may also include a controller 102 and a motor 101, and the controller 102 is used to control the battery to power the motor 101, for example, for starting, navigating and operating power requirements of the vehicle 1 during driving.

[0066] In some embodiments of the present application, the battery can be used not only as an operating power source for the vehicle 1 , but also 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 .

[0067] In order to meet different power requirements, the battery 2 may include a plurality of battery cells, and a battery cell refers to the smallest unit that constitutes a battery module or a battery pack. A plurality of battery cells can be connected in series and / or in parallel via electrode terminals for use in various applications. The battery 2 mentioned in the present application includes a battery module or a battery pack. Among them, a plurality of battery cells can be connected in series, in parallel, or in mixed connection, and mixed connection refers to a mixture of series and parallel connection. In the embodiments of the present application, a plurality of battery cells can directly constitute a battery pack, or they can first constitute a battery module, and then the battery module constitutes a battery pack.

[0068] Figure 2A schematic structural diagram of a battery 2 according to an embodiment of the present application is shown.

[0069] like Figure 2 As shown, the battery includes a housing 202 and a battery cell (not shown), and the battery cell is accommodated in the housing 202 .

[0070] The box 202 may be a simple three-dimensional structure such as a single cuboid, cylinder or sphere, or a complex three-dimensional structure composed of simple three-dimensional structures such as cuboids, cylinders or spheres. The box 202 may be made of alloy materials such as aluminum alloy, iron alloy, polymer materials such as polycarbonate, polyisocyanurate foam plastic, or composite materials such as glass fiber and epoxy resin.

[0071] The box 202 is used to accommodate the battery cells, and the box 202 can be of various structures. In some embodiments, the box 202 can include a first box portion 2021 and a second box portion 2022, the first box portion 2021 and the second box portion 2022 cover each other, and the first box portion 2021 and the second box portion 2022 jointly define a storage space for accommodating the battery cells 3. The second box portion 2022 can be a hollow structure with one end open, the first box portion 2021 is a plate-like structure, and the first box portion 2021 covers the open side of the second box portion 2022 to form a box 202 with a storage space; the first box portion 2021 and the second box portion 2022 can also be hollow structures with one side open, and the open side of the first box portion 2021 covers the open side of the second box portion 2022 to form a box 202 with a storage space. Of course, the first box body 2021 and the second box body 2022 can be in various shapes, such as a cylinder, a cuboid, etc.

[0072] In order to improve the sealing performance after the first box body 2021 and the second box body 2022 are connected, a sealing member, such as a sealant, a sealing ring, etc., may also be provided between the first box body 2021 and the second box body 2022 .

[0073] Assuming that the first box body portion 2021 covers the top of the second box body portion 2022 , the first box body portion 2021 can also be referred to as an upper box cover, and the second box body portion 2022 can also be referred to as a lower box cover.

[0074] In the battery 2, there can be one or more battery cells. If there are multiple battery cells, the multiple battery cells can be connected in series, in parallel, or in mixed connection. Mixed connection means that multiple battery cells are connected in series and in parallel. Multiple battery cells can be directly connected in series, in parallel, or in mixed connection, and then the whole formed by the multiple battery cells can be accommodated in the box 202; of course, multiple battery cells can also be connected in series, in parallel, or in mixed connection to form a battery module 201, and then multiple battery modules 201 can be connected in series, in parallel, or in mixed connection to form a whole, and then accommodated in the box 202.

[0075] Figure 3 A schematic structural diagram of a battery module 201 according to an embodiment of the present application is shown.

[0076] In some embodiments, Figure 2 and Figure 3 As shown, there are multiple battery cells 3, and the multiple battery cells 3 are first connected in series, parallel or mixed to form a battery module 201. The multiple battery modules 201 are then connected in series, parallel or mixed to form a whole, and are accommodated in the box 202.

[0077] The multiple battery cells 3 in the battery module 201 can be electrically connected via a busbar component to achieve parallel connection, series connection, or mixed connection of the multiple battery cells 3 in the battery module 201 .

[0078] In the present application, the battery cell 3 may include a lithium-ion battery cell, a sodium-ion battery cell, a magnesium-ion battery cell, etc., which is not limited in the embodiments of the present application.

[0079] Figure 4 The schematic diagram of the structure of the battery cell 3 provided in some embodiments of the present application. The battery cell 3 refers to the smallest unit that constitutes the battery. Figure 4 The battery cell 3 includes a top cover assembly 6 , a shell 4 and an electrode assembly 5 .

[0080] The electrode assembly 5 is a component in the battery cell 3 where electrochemical reactions occur. One or more electrode assemblies 5 may be included in the housing 4. The electrode assembly 5 is mainly formed by winding or stacking pole sheets, which are divided into positive pole sheets and negative pole sheets, and a separator is usually provided between the positive pole sheet and the negative pole sheet. The parts of the positive pole sheet and the negative pole sheet with active materials constitute the electrode body 52, and the parts of the positive pole sheet and the negative pole sheet without active materials each constitute the pole ear 51. The positive pole ear and the negative pole ear may be located together at one end of the electrode body 52 or at both ends of the electrode body 52 respectively. During the charge and discharge process of the battery, the positive active material and the negative active material react with the electrolyte, and the pole ear 51 connects the electrode terminal 61 to form a current loop.

[0081] The shell 4 is a component used to cooperate with the top cover assembly 6 to form the internal environment of the battery cell 3, wherein the formed internal environment can be used to accommodate the electrode assembly 5, the electrolyte (not shown in the figure) and other components. The shell 4 and the top cover assembly 6 can be independent components, and an opening can be set on the shell 4, and the internal environment of the battery cell 3 is formed by covering the opening with the top cover assembly 6 at the opening. Optionally, the top cover assembly 6 and the shell 4 can also be integrated. Optionally, the top cover assembly 6 and the shell 4 can form a common connection surface before other components are put into the shell, and when the interior of the shell 4 needs to be encapsulated, the top cover assembly 6 covers the shell 4. The shell 4 can be of various shapes and sizes, such as a rectangular parallelepiped, a cylindrical shape, a hexagonal prism, etc. The shape of the shell 4 can be determined according to the specific shape and size of the electrode assembly 5. The material of the shell 4 can be various, and the material of the shell 4 is copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc.

[0082] In some embodiments, Figure 4 As shown, two electrode terminals 61 may be provided in the top cap assembly 6. One electrode terminal 61 of the top cap assembly 6 is electrically connected to one pole ear 51 (e.g., a positive pole ear) of the electrode assembly 5. Another electrode terminal 61 in the top cap assembly 6 is electrically connected to another pole ear 51 (e.g., a negative pole ear) of the electrode assembly 5.

[0083] See also Figure 5 and Figure 6 , Figure 5 is an exploded diagram of a battery cell provided in one embodiment of the present application; Figure 6 It is a structural schematic diagram of a battery cell switching mechanism provided in one embodiment of the present application.

[0084] First, as Figure 5 and Figure 6 As shown, the present application provides a battery cell 3, the battery cell 3 includes a top cover assembly 6, an electrode assembly 5 and a switching mechanism 7, the top cover assembly 6 is provided with an electrode terminal 61; the electrode assembly 5 includes a pole lug 51; the switching mechanism 7 is arranged between the top cover assembly 6 and the electrode assembly 5, wherein each electrode terminal 61 includes two or more poles 62 arranged at intervals, the switching mechanism 7 includes a first connecting portion 71 and a second connecting portion 72 connected to each other, the first connecting portion 71 includes two or more sub-connecting portions 711 arranged at intervals, each sub-connecting portion 711 is respectively connected to each pole 62, and the second connecting portion 72 is connected to the pole lug 51.

[0085] In the scheme of the embodiment of the present application, the battery cell 3 includes a top cover assembly 6, an electrode assembly 5 and an adapter mechanism 7, the top cover assembly 6 is provided with an electrode terminal 61, each electrode terminal 61 includes two or more poles 62 arranged at intervals, the electrode assembly 5 includes a pole ear 51, the adapter mechanism 7 is arranged between the top cover assembly 6 and the electrode assembly 5, the adapter mechanism 7 includes a first connection portion 71 and a second connection portion 72 connected to each other, the second connection portion 72 is connected to the pole ear 51 of the electrode assembly 5, the first connection portion 71 includes two or more sub-connection portions 711 arranged at intervals, each sub-connection portion 711 is correspondingly connected to each pole 62, so that the electrode terminal 61 can be electrically connected to the electrode assembly 5 through the first connection portion 71 and the second connection portion 72, thereby by arranging two or more sub-connection portions 711 at intervals on the adapter mechanism 7, so that the adapter mechanism 7 can be fully connected to each pole 62 of the terminal, thereby increasing the connection area between the pole 62 and the adapter mechanism 7, thereby increasing the current capacity between the electrode terminal 61 and the adapter mechanism 7, and thereby improving the overall current performance of the battery.

[0086] Two electrode terminals 61 are arranged at intervals on the top cover assembly 6, and the two electrode terminals 61 serve as the positive terminal and the negative terminal of the battery cell 3 respectively. At least two poles 62 are arranged at intervals in the electrode terminal 61, and each pole 62 is electrically connected to the electrode assembly 5 through the switching mechanism 7, so that current can flow between the electrode terminal 61 and the electrode assembly 5.

[0087] The electrode assembly 5 includes an electrode body 52 and a tab 51 connected to each other. The tab 51 includes a positive tab 51 and a negative tab 51. The positive tab 51 is electrically connected to the positive terminal, and the negative tab 51 is electrically connected to the negative terminal. The tab 51 and each pole 62 are connected through a switching mechanism 7.

[0088] The battery cell 3 further includes a shell 4 , which includes an opening at at least one end. The top cover assembly 6 covers the opening, and the electrode assembly 5 is accommodated in the shell 4 .

[0089] The battery cell 3 includes two switching mechanisms 7, which are respectively connected to the positive terminal and the negative terminal. The switching mechanism 7 can be made of conductive materials such as copper, aluminum or stainless steel.

[0090] The adapter mechanism 7 includes a first connection portion 71 and a second connection portion 72 connected to each other, the second connection portion 72 is connected to the pole lug 51, and the first connection portion 71 includes a plurality of sub-connection portions 711 correspondingly connected to each pole 62. In the adapter mechanism 7 and the electrode terminal 61 connected thereto, the number and arrangement of the sub-connection portions 711 are the same as the number and arrangement of the poles 62, so that each pole 62 can be connected to the sub-connection portion 711.

[0091] Exemplarily, the electrode terminal 61 includes two poles 62 spaced apart, the first connection part 71 includes two sub-connection parts 711 spaced apart, the adapter mechanism 7 includes a first connection part 71 and a second connection part 72, the spacing direction of the two poles 62 is the same as the extension direction of the second connection part 72, the two sub-connection parts 711 are respectively arranged at both ends of the second connection part 72, or the two sub-connection parts 711 are respectively arranged at one end of the second connection part 72, so as to reduce the size of the adapter mechanism 7; or, the electrode terminal 61 includes two poles 62 spaced apart, the first connection part 71 includes two sub-connection parts 711 spaced apart, the adapter mechanism 7 includes a second connection part 72 and two second connection parts 72, the two second connection parts 72 are respectively connected to part of the pole ears 51, and the two second connection parts 72 are respectively arranged on both sides of the first connection part 71, so as to improve the stability of the adapter structure.

[0092] The first connection part 71 includes sub-connection parts 711 arranged at intervals. Specifically, each sub-connection part 711 is a plate member arranged at intervals, or the first connection part 71 is an integral plate member, and each sub-connection part 711 is a mutually spaced area on the plate member connected to the pole 62.

[0093] Optionally, the adapter mechanism 7 and the pole lug 51 are connected by bonding or welding to improve the connection reliability between the adapter mechanism 7 and the pole lug 51; the adapter mechanism 7 and the pole 62 are connected by bonding or welding to improve the connection reliability between the adapter mechanism 7 and the pole 62.

[0094] Optionally, the first connecting portion 71 and the second connecting portion 72 are integrally formed to improve the stability of the switching mechanism 7 .

[0095] See also Figure 7 , Figure 7 It is a side view of a switching mechanism of a battery cell provided in one embodiment of the present application.

[0096] In some embodiments, Figure 5 and Figure 7 As shown, the second connecting portion 72 includes an extension section 721 and a bending section 722 that are connected to each other. In the first direction X, the bending section 722 is located between the two extension sections 721. The extension section 721 is connected to the sub-connecting portion 711. The bending section 722 is formed by bending part of the second connecting portion 72 so that the second connecting portion 72 can be deformed in the first direction X.

[0097] In these embodiments, the second connection portion 72 includes an extension section 721 and a bending section 722 that are connected to each other. The bending section 722 is located between the two extension sections 721. The extension section 721 is connected to the sub-connection portion 711. The bending section 722 is formed by bending a portion of the second connection portion 72, so that during the connection between the first connection portion 71 and the pole 62, the bending section 722 is deformably arranged in the first direction X, so as to improve the extensibility of the adapter mechanism 7 in the first direction X through the bending section 722, so as to reduce the risk of the adapter mechanism 7 breaking under the action of the connection stress.

[0098] During the welding process of the adapter mechanism 7 and the pole 62, the adapter mechanism 7 will have a tendency to stretch in the first direction X due to the welding stress. Therefore, in order to reduce the risk of the adapter mechanism 7 breaking during the welding process, a bending section 722 is formed at the second connecting portion 72 to enhance the deformation ability of the adapter mechanism 7 in the first direction X and reduce the risk of damage to the adapter mechanism 7.

[0099] Optionally, the bent section 722 is connected to both side edges of the second connecting portion 72 in the width direction to improve the ductility of the second connecting portion 72 .

[0100] Optionally, a plurality of bending segments 722 are arranged at intervals in the first direction X, so as to enhance the ductility of the second connecting portion 72 while reducing the size requirement of the second connecting portion 72 in the thickness direction of the switching mechanism 7 .

[0101] Optionally, the bent section 722 may be formed by punching or bending the base material of the second connecting portion 72 .

[0102] See also Figure 8 , Figure 8 It is a schematic diagram of an expanded battery cell provided in one embodiment of the present application.

[0103] In some embodiments, Figure 6 and Figure 8 As shown, the pole lug 51 includes a welding region 512 , the pole lug 51 is connected to the second connecting portion 72 at the welding region 512 , and the welding region 512 and the bending section 722 are alternately arranged.

[0104] In these embodiments, the pole lug 51 includes a welding area 512 , the pole lug 51 is connected to the second connecting portion 72 at the welding area 512 , and the welding area 512 and the bending section 722 are alternately arranged to reduce the influence of the bending section 722 on the connection effect between the adapter mechanism 7 and the pole lug 51 .

[0105] Specifically, the welding area 512 is only arranged in the area corresponding to the extension section 721, so that the welding area 512 and the bending section 722 are staggered to prevent the deformation of the second connecting portion 72 in the bending section 722 from affecting the welding effect of the tab 51 and the second connecting portion 72. The shape of the welding area 512 can be designed by itself, and illustratively, the welding area 512 is rectangular or circular.

[0106] Exemplarily, the second connection portion 72 includes a bending section 722 and two extension sections 721 arranged at both ends of the bending section 722 in the first direction X. The welding area 512 is connected to at least one of the extension sections 721 to separate the bending section 722 and the welding area 512. When the two sub-connection portions 711 and the pole 62 are connected, the bending section 722 can absorb the welding stress by deformation to reduce the risk of breakage of the second connection portion 72.

[0107] Optionally, the two extension segments 721 have different sizes in the first direction X, and the welding area 512 is connected to the extension segment 721 with a longer size to improve the connection reliability between the second connecting portion 72 and the tab 51 .

[0108] In some embodiments, Figure 6 and Figure 8 As shown, the bent section 722 is formed by bending a portion of the second connecting portion 72 toward the top cover assembly 6 .

[0109] In these embodiments, the bent section 722 is formed by bending a portion of the second connecting portion 72 toward the top cover assembly 6 , so as to reduce the risk of the bent section 722 damaging the tab 51 .

[0110] Specifically, a groove is formed on one side of the second connection portion 72 facing the pole lug 51 in the thickness direction, and a protrusion is formed on the side of the second connection portion 72 facing away from the pole lug 51 . The protrusion and the groove exist correspondingly in the thickness direction of the second connection portion 72 .

[0111] See also Fig. 9 and Fig.10 , Fig. 9 is a top view of a switching mechanism of a battery cell provided in one embodiment of the present application; Fig.10 It is a structural schematic diagram of a battery cell switching mechanism provided in one embodiment of the present application.

[0112] In some embodiments, Figure 5 , Fig. 9 and Fig.10As shown, the sub-connection portion 711 is respectively provided with a first connection area 7111 and a second connection area 7112 on both side surfaces in the thickness direction thereof, the pole 62 is connected in the first connection area 7111 and the sub-connection portion 711, embossing is provided in the second connection area 7112, and the projection of the first connection area 7111 in the thickness direction of the sub-connection portion 711 and the projection of the second connection area 7112 in the thickness direction at least partially overlap.

[0113] In these embodiments, the sub-connection portion 711 is respectively provided with a first connection area 7111 and a second connection area 7112 on its two side surfaces in the thickness direction, the projection of the first connection area 7111 in the thickness direction of the sub-connection portion 711 and the projection of the second connection area 7112 in the thickness direction at least partially overlap, the pole 62 is connected to the sub-connection portion 711 in the first connection area 7111, and embossing is provided in the second connection area 7112, so that during the welding process of the pole 62 and the adapter mechanism 7, the embossing of the second connection area 7112 can reduce the attenuation of laser energy, so as to improve the welding effect of the pole 62 and the adapter laser.

[0114] Optionally, the embossing of the second connection area 7112 may be a groove or a bump that is etched, machined, or rolled. Exemplarily, the embossing of the second connection area 7112 is a dot-shaped groove arranged in an array; or the embossing of the second connection area 7112 is a strip-shaped groove arranged in an array; or the embossing of the second connection area 7112 is a dot-shaped protrusion arranged in an array.

[0115] The pole 62 and the adapter 7 are connected together by laser welding. The laser beam acts on the second connection area 7112. The embossing of the second connection area 7112 can reduce the reflection or scattering of the laser beam to concentrate the laser energy to improve the welding quality of the pole 62 and the first connection area 7111.

[0116] Optionally, in the thickness direction of the sub-connection portion 711 , the orthographic projection of the first connection region 7111 is located within the second connection region 7112 , so as to improve the welding quality between the pole 62 and the sub-connection portion 711 .

[0117] Optionally, the sub-connection portion 711 includes a first portion and a second portion connected to each other, the second connection area 7112 and the first connection area 7111 are arranged on the first portion, and the second portion is arranged on a side of the first portion away from the other sub-connection portion 711. By arranging the second portion on the sub-connection portion 711, it is convenient to clamp the adapter mechanism 7 during the assembly process of the battery cell 3.

[0118] In some embodiments, Figure 5 and Figure 6As shown, the pole ear 51 includes two sub-pole ears 511 arranged opposite to each other along the thickness direction of the electrode assembly 5, the switching mechanism 7 includes two second connecting parts 72 arranged opposite to each other along the thickness direction of the electrode assembly 5, the first connecting part 71 is connected between the two second connecting parts 72, and the two second connecting parts 72 are respectively connected to the two sub-pole ears 511.

[0119] In these embodiments, the pole lug 51 includes two sub-pole lugs 511 arranged opposite to each other along the thickness direction of the electrode assembly 5, and the adapter mechanism 7 includes two second connecting portions 72 arranged opposite to each other along the thickness direction of the electrode assembly 5, so that the second connecting portions 72 are stably connected to the sub-pole lugs 511 respectively, and the first connecting portion 71 is connected between the two second connecting portions 72, so that during the connection process between the second connecting portion 72 and the pole lug 51, the forces on both sides of the first connecting portion 71 are balanced, and no excessive misalignment will be generated, thereby reducing the difficulty of connecting the pole 62 and the first connecting portion 71; and the connection of the first connecting portion 71 between the two second connecting portions 72 also helps to improve the overall stability of the adapter mechanism 7; and because the first connecting portion 71 is located between the two sub-pole lugs 511, the first connecting portion 71 does not limit the extension length of the sub-pole lug 511, and the extension size of the sub-pole lug 511 can be more conveniently designed to improve the overcurrent performance of the battery cell 3.

[0120] The pole lug 51 includes two oppositely arranged sub-pole lugs 511, each of which is connected to a second connecting portion 72 to increase the connection area between the pole lug 51 and the adapter mechanism 7, improve the current carrying capacity of the battery cell 3, and reduce the risk of separation of the adapter mechanism 7 and the pole lug 51 under the action of external force.

[0121] Optionally, the two sub-pole lugs 511 belonging to the same pole lug 51 have the same size, and the two first connecting portions 71 have the same size, so as to balance the current flow capacity of the two first connecting portions 71 of the switching mechanism 7 .

[0122] The first connection portion 71 is disposed between the two second connection portions 72 so that during the welding process between the second connection portion 72 and the pole lug 51 , both sides of the first connection portion 71 are subjected to uniform force, thereby reducing the difficulty of aligning the first connection portion 71 and the pole 62 .

[0123] In some embodiments, Figure 5 , Figure 6 and Fig.10 As shown, the sub-connecting portion 711 includes a bottom wall 7113 and a side wall 7114 , one end of the side wall 7114 is connected to the second connecting portion 72 , the other end of the side wall 7114 extends away from the top cover assembly 6 and is connected to the bottom wall 7113 , and the pole 62 is connected to the bottom wall 7113 .

[0124] In these embodiments, the sub-connecting portion 711 includes a bottom wall 7113 and a side wall 7114, one end of the side wall 7114 is connected to the second connecting portion 72, the other end of the side wall 7114 extends away from the top cover assembly 6 and is connected to the bottom wall 7113, the pole 62 is connected to the bottom wall 7113, the bottom wall 7113 and the side wall 7114 form a groove for avoiding the pole 62, and the avoidance groove can also provide a positioning function during the welding process of the adapter mechanism 7 and the pole 62, so as to reduce the difficulty of connecting the top cover assembly 6 and the adapter mechanism 7.

[0125] Part of the pole 62 extends out of the surface of the top cover assembly 6 facing the electrode assembly 5 , and the extended part of the pole 62 is connected to the adapter mechanism 7 to reduce the difficulty of connecting the pole 62 and the adapter mechanism 7 .

[0126] The embossing is arranged on a side surface of the bottom wall 7113 facing away from the top cover assembly 6 , and the pole 62 is welded to a side surface of the bottom wall 7113 facing the top cover assembly 6 .

[0127] In some embodiments, Fig.10 As shown, two adjacent sub-connection portions 711 and two second connection portions 72 enclose a hollow area 74 .

[0128] In these embodiments, two adjacent sub-connecting portions 711 and two second connecting portions 72 enclose a hollow area 74 , and the hollow area 74 can reduce the weight of the adapter mechanism 7 and save the material cost of the adapter mechanism 7 .

[0129] Optionally, each sub-connection portion 711 and the second connection portion 72 are formed separately, and are interconnected to enclose a hollow area 74; or two adjacent sub-connection portions 711 and two second connection portions 72 are formed as one piece and enclose a hollow area 74.

[0130] Optionally, the shape of the hollow area 74 can be flexibly designed. Exemplarily, the hollow area 74 is a circular hole or a rectangular hole.

[0131] See also Fig.11 , Fig.12 and Fig.13 , Fig.11 It is a partial structural schematic diagram of a battery cell provided in one embodiment of the present application; Fig.12 yes Fig.11 Sectional view at AA in the middle; Fig.13 yes Fig.12 Schematic diagram of the enlarged structure at point B in the middle.

[0132] In some embodiments, Figures 10 to 13As shown, the top cover assembly 6 includes a first terminal 611 and a second terminal 612 with opposite polarities, and the battery cell 3 also includes an overcharge protection mechanism 8, which is connected to the top cover assembly 6 and is arranged between the top cover assembly 6 and the adapter mechanism 7. The overcharge protection mechanism 8 at least partially overlaps with the positive projection of the adapter mechanism 7 and the hollow area 74. The overcharge protection mechanism 8 is configured such that when the internal pressure of the battery cell 3 reaches a first threshold, the pressure acts on the overcharge protection mechanism 8 via the through hole, and the first terminal 611 and the second terminal 612 are electrically connected through the overcharge protection mechanism 8.

[0133] In these embodiments, the battery cell 3 also includes an overcharge protection mechanism 8, which is arranged between the top cover assembly 6 and the adapter mechanism 7. The overcharge protection mechanism 8 at the orthographic projection of the adapter mechanism 7 and the hollow area 74 at least partially overlap. The overcharge protection mechanism 8 is configured to connect the first terminal 611 and the second terminal 612 when the internal pressure of the battery cell 3 reaches a first threshold value, so as to short-circuit the external power supply circuit of the battery cell 3 to reduce the risk of thermal runaway of the battery cell 3; and by arranging the overcharge protection mechanism 8 between the hollow area 74 and the top cover assembly 6, the internal pressure of the battery cell 3 can act on the overcharge protection mechanism 8 through the hollow area 74. The hollow area 74 not only has the effect of reducing the self-weight of the adapter mechanism 7, but can also be reused as a pressure channel between the overcharge protection mechanism 8 and the internal environment of the battery cell 3, which reflects the efficient use of the internal space of the battery by the adapter mechanism 7 provided in this embodiment.

[0134] One of the first terminal 611 and the second terminal 612 is a positive terminal, and the other of the first terminal 611 and the second terminal 612 is a negative terminal.

[0135] Specifically, the top cover assembly 6 also includes a metal layer and an insulating layer connected to each other, and only an overcharge protection mechanism 8 is set at the hollow area 74 of the adapter mechanism 7 connected to the second terminal 612 to save the cost of the overcharge protection mechanism 8. The pole 62 of the first terminal 611 is connected to the metal layer, and the pole 62 of the second terminal 612 is insulated from the metal layer. The overcharge protection mechanism 8 includes a flip sheet 81, which is electrically connected to the metal layer. When the internal pressure of the battery cell 3 does not reach the first threshold, the flip sheet 81 and the pole 62 of the second terminal 612 are arranged at intervals. The overcharge protection mechanism 8 is configured so that when the internal pressure of the battery cell 3 reaches the first threshold, the internal pressure acts on the flip sheet 81 through the hollow area 74, and the flip sheet 81 flips toward the top cover assembly 6 to contact the pole 62 of the second terminal 612, thereby electrically connecting the pole 62 of the first terminal 611 and the second terminal 612, thereby realizing an external short circuit of the battery cell 3. Those skilled in the art often refer to the overcharge protection mechanism 8 that realizes an external short circuit by turning over the flip sheet 81 to conduct the two electrode terminals 61 with opposite polarities as a safety short circuit device, namely, SSD.

[0136] The top cover assembly 6 also includes a metal layer and an insulating layer connected to each other, and an overcharge protection mechanism 8 is provided at each of the two switching mechanisms 7 to improve the reliability of the overcharge protection mechanism 8. The poles 62 of the first terminal 611 and the second terminal 612 are both insulated and connected to the metal layer, and when the internal pressure of the battery 2 reaches the first threshold, the flip pieces 81 of the two overcharge protection mechanisms 8 are connected to the metal layer and the poles 62 of the first terminal 611 and the second terminal 612, respectively.

[0137] Optionally, the center point of the hollow area 74 and the center point of the overcharge protection mechanism 8 are on a straight line extending along the thickness direction of the adapter mechanism 7 , so that the internal pressure of the battery cell 3 can fully drive the overcharge protection mechanism 8 .

[0138] In some embodiments, Fig.10 and Fig.11 As shown, the second connecting part 72 of the transfer mechanism 7 includes a substrate 723 and a weakened section 724 connected to the substrate 723, the substrate 723 is connected to the pole ear 51, the weakened section 724 is connected to the substrate 723 and the sub-connecting part 711, and along the arrangement direction of the first connecting part 71 and the second connecting part 72, the cross-sectional area of ​​the weakened section 724 is smaller than the cross-sectional area of ​​the sub-connecting part 711.

[0139] In these embodiments, the second connecting portion 72 of the adapter mechanism 7 includes a substrate 723 and a weakened section 724 connected to the substrate 723, the substrate 723 is connected to the pole ear 51, the weakened section 724 is connected to the substrate 723 and the sub-connecting portion 711, and along the arrangement direction of the first connecting portion 71 and the second connecting portion 72, the cross-sectional area of ​​the weakened section 724 is smaller than the cross-sectional area of ​​the sub-connecting portion 711, so that when the overcharge protection mechanism 8 connects the first terminal 611 and the second terminal 612, the high temperature generated by the short circuit between the first terminal 611 and the second terminal 612 can melt the weakened section 724, so that the electrode terminal 61 and the electrode assembly 5 are disconnected, thereby further reducing the risk of thermal runaway of the battery cell 3 and improving the reliability of the battery cell 3.

[0140] Optionally, the weakened section 724 can be formed by a necking design between the substrate 723 and the sub-connecting portion 711 to simplify the processing steps of the transition mechanism 7; or a notched groove can be set between the substrate 723 and the sub-connecting portion 711, with the bottom portion of the groove serving as the weakened section 724 to reduce the design difficulty of the transition mechanism 7.

[0141] Optionally, a plurality of weakened sections 724 are provided on the adapter mechanism 7 , and each weakened section 724 has the same size, so that when the internal temperature of the battery cell 3 rises, each weakened section 724 can be quickly melted to reduce the risk of thermal runaway of the battery cell 3 .

[0142] In some embodiments, Fig.11 and Fig.12As shown, the adapter mechanism 7 includes a first adapter mechanism 75 and a second adapter mechanism 76. The first adapter mechanism 75 is connected to the first terminal 611, and the second adapter mechanism 76 is connected to the second terminal 612. The melting point of the first adapter mechanism 75 is lower than the melting point of the second adapter mechanism 76, and the weakened section 724 is arranged on the first adapter mechanism 75.

[0143] In these embodiments, the adapter mechanism 7 includes a first adapter mechanism 75 and a second adapter mechanism 76. The first adapter mechanism 75 is connected to the first terminal 611, and the second adapter mechanism 76 is connected to the second terminal 612. The melting point of the first adapter mechanism 75 is lower than the melting point of the second adapter mechanism 76. The weakened section 724 is arranged on the first adapter mechanism 75 to facilitate the melting of the weakened section 724 of the first adapter mechanism 75 under high temperature conditions. In addition, the weakened section 724 is processed only on the first adapter mechanism 75, which reduces the processing difficulty of the second adapter mechanism 76 and helps to improve the overall processing efficiency of the adapter mechanism 7.

[0144] Optionally, the first terminal 611 is a negative terminal, and the material of the first switching mechanism 75 is aluminum; the second terminal 612 is a positive terminal, and the material of the second switching mechanism 76 is copper.

[0145] In a second aspect, the present application provides a battery, comprising a battery cell according to any one of the embodiments of the first aspect.

[0146] In a third aspect, the present application provides an electrical device, comprising the battery of the above-mentioned second aspect embodiment.

[0147] In some embodiments, Figures 1 to 13As shown, the battery cell 3 includes a top cover assembly 6, an electrode assembly 5, a switching mechanism 7 and an overcharge protection mechanism 8, the top cover assembly 6 is provided with an electrode terminal 61; the electrode assembly 5 includes a pole ear 51, and the pole ear 51 includes two sub-pole ears 511 arranged oppositely along the thickness direction of the electrode assembly 5; the switching mechanism 7 is arranged between the top cover assembly 6 and the electrode assembly 5, wherein the terminal includes two or more poles 62 arranged at intervals, the switching mechanism 7 includes two second connecting parts 72 arranged oppositely along the thickness direction of the electrode assembly 5, the first connecting part 71 is connected between the two second connecting parts 72, and the two second connecting parts 72 are respectively connected to the two sub-pole ears 511, the first connecting part 71 includes two or more sub-connecting parts 711 arranged at intervals, each sub-connecting part 711 is respectively connected to each pole 62, and the sub-connecting part 711 is respectively provided with a first connecting area 7111 and a second connecting area 7112 on both side surfaces in the thickness direction thereof, the pole 62 is connected to the sub-connecting part 711 in the first connecting area 7111, and the second connecting area 7112 is respectively provided on the two side surfaces in the thickness direction thereof, The connection area 7112 is provided with embossing, the projection of the first connection area 7111 in the thickness direction of the sub-connection part 711 and the projection of the second connection area 7112 in the thickness direction at least partially overlap, the sub-connection part 711 includes a bottom wall 7113 and a side wall 7114, one end of the side wall 7114 is connected to the second connection part 72, the other end of the side wall 7114 extends away from the top cover assembly 6 and is connected to the bottom wall 7113, the pole 62 is connected to the bottom wall 7113, and the second connection part 72 includes mutually connected extension walls 7113 and 7114. The extension section 721 and the bending section 722, in the first direction X, the bending section 722 is located between the two extension sections 721, the extension section 721 is connected to the sub-connection portion 711, and the bending section 722 is formed by bending a portion of the second connection portion 72 toward the top cover assembly 6, so that the second connection portion 72 is deformable in the first direction X, the second connection portion 72 includes a welding area 512, the pole ear 51 is connected to the second connection portion 72 in the welding area 512, and the welding area 512 and the bending section 722 are staggered;The two adjacent sub-connecting parts 711 and the two second connecting parts 72 enclose a hollow area 74, the top cover assembly 6 includes a first terminal 611 and a second terminal 612 with opposite polarities, and the battery cell 3 also includes an overcharge protection mechanism 8, which is connected to the top cover assembly 6 and is arranged between the top cover assembly 6 and the adapter mechanism 7. The orthographic projection of the overcharge protection mechanism 8 on the adapter mechanism 7 at least partially overlaps with the hollow area 74, and the overcharge protection mechanism 8 is configured to be in a state where the internal pressure of the battery cell 3 reaches a first threshold value. When the value is reached, the pressure acts on the overcharge protection mechanism 8 through the through hole, the first terminal 611 and the second terminal 612 are electrically connected through the overcharge protection mechanism 8, the second connection part 72 of the switching mechanism 7 includes a substrate 723 and a weakened section 724 connected to the substrate 723, the substrate 723 is connected to the pole ear 51, the weakened section 724 is connected to the substrate 723 and the sub-connection part 711, and along the arrangement direction of the first connection part 71 and the second connection part 72, the cross-sectional area of ​​the weakened section 724 is smaller than the cross-sectional area of ​​the sub-connection part 711. ;

[0148] In the scheme of the embodiment of the present application, the battery cell 3 includes a top cover assembly 6, an electrode assembly 5 and an adapter mechanism 7, the top cover assembly 6 is provided with an electrode terminal 61, the electrode terminal 61 includes two or more poles 62 arranged at intervals, the electrode assembly 5 includes a pole ear 51, the adapter mechanism 7 is arranged between the top cover assembly 6 and the electrode assembly 5, the adapter mechanism 7 includes a first connection portion 71 and a second connection portion 72 connected to each other, the second connection portion 72 is connected to the pole ear 51 of the electrode assembly 5, the first connection portion 71 includes two or more sub-connection portions 711 arranged at intervals, each sub-connection portion 711 is correspondingly connected to each pole 62, so that the electrode terminal 61 can be electrically connected to the electrode assembly 5 through the first connection portion 71 and the second connection portion 72, thereby by arranging two or more sub-connection portions 711 at intervals on the adapter mechanism 7, so that the adapter mechanism 7 can be fully connected to each pole 62 of the terminal, thereby increasing the connection area between the pole 62 and the adapter mechanism 7, thereby increasing the current capacity between the electrode terminal 61 and the adapter mechanism 7, and thereby improving the overall current performance of the battery 2.

[0149] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them; although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application, and they should all be included in the scope of the claims and specification of the present application. In particular, as long as there is no structural conflict, the various technical features mentioned in the various embodiments can be combined in any way. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions that fall within the scope of the claims.

Claims

1. A battery cell, characterized in that: include: A top cover assembly, wherein the top cover assembly is provided with an electrode terminal; Electrode assembly, including tabs; A switching mechanism is provided between the top cover assembly and the electrode assembly, Wherein, each of the electrode terminals includes two or more poles arranged at intervals, the switching mechanism includes a first connecting part and a second connecting part connected to each other, the first connecting part includes two or more sub-connecting parts arranged at intervals, each of the sub-connecting parts is respectively connected to each pole, and the second connecting part is connected to the pole ear.

2. The battery cell according to claim 1, characterized in that: The second connecting portion includes an extension segment and a bending segment that are connected to each other. In the first direction, the bending segment is located between the two extension segments. The extension segment is connected to the sub-connecting portion. The bending segment is formed by bending a portion of the second connecting portion so that the second connecting portion can be deformed in the first direction.

3. The battery cell according to claim 2, characterized in that: The pole lug comprises a welding region, the pole lug is connected to the second connecting portion at the welding region, and the welding region and the bending section are alternately arranged.

4. The battery cell according to claim 2, characterized in that: The bent section is formed by bending a portion of the second connecting portion toward the top cover assembly.

5. The battery cell according to claim 1, characterized in that: The sub-connection part is respectively provided with a first connection area and a second connection area on both side surfaces in the thickness direction thereof, the pole is connected to the sub-connection part in the first connection area, embossing is provided in the second connection area, and the projection of the first connection area in the thickness direction of the sub-connection part and the projection of the second connection area in the thickness direction at least partially overlap.

6. The battery cell according to claim 1, characterized in that: The electrode tab includes two sub-electrode tabs arranged opposite to each other along the thickness direction of the electrode assembly, the switching mechanism includes two second connecting parts arranged opposite to each other along the thickness direction of the electrode assembly, the first connecting part is connected between the two second connecting parts, The two second connecting parts are respectively connected to the two sub-electrode ears.

7. The battery cell according to claim 6, characterized in that: The sub-connecting portion includes a bottom wall and a side wall, one end of the side wall is connected to the second connecting portion, the other end of the side wall extends away from the top cover assembly and is connected to the bottom wall, and the pole is connected to the bottom wall.

8. The battery cell according to claim 6, characterized in that: Two adjacent sub-connecting portions and two adjacent second connecting portions enclose a hollow area.

9. The battery cell according to claim 8, characterized in that: The electrode terminal includes a first terminal and a second terminal with opposite polarities. The battery cell also includes an overcharge protection mechanism, which is connected to the top cover assembly and is arranged between the top cover assembly and the adapter mechanism. The overcharge protection mechanism at least partially overlaps with the orthographic projection of the adapter mechanism and the hollow area. The overcharge protection mechanism is configured such that when the internal pressure of the battery cell reaches a first threshold, the pressure acts on the overcharge protection mechanism via the through hole, and the first terminal and the second terminal are electrically connected through the overcharge protection mechanism.

10. The battery cell according to claim 9, characterized in that: The second connection part of the switching mechanism includes a substrate and a weakened section connected to the substrate, the substrate is connected to the tab, and the weakened section is connected to the substrate and the sub-connection part. Along the arrangement direction of the first connecting portion and the second connecting portion, a cross-sectional area of ​​the weakened section is smaller than a cross-sectional area of ​​the sub-connecting portion.

11. The battery cell according to claim 10, characterized in that: The switching mechanism includes a first switching mechanism and a second switching mechanism, the first switching mechanism is connected to the first terminal, and the second switching mechanism is connected to the second terminal. The melting point of the first transition mechanism is lower than that of the second transition mechanism, and the weakened section is arranged on the first transition mechanism.

12. A battery, characterized in that: A battery cell comprising any one of claims 1 to 11.

13. An electrical device, characterized in that: A battery comprising the battery as claimed in claim 12 above.

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