Battery monomer, battery and electric device

Abstract

The invention discloses a battery monomer, a battery and an electric device, and belongs to the technical field of batteries. Wherein the single battery comprises a shell assembly and a battery cell assembly, the shell assembly comprises a shell and a first pole arranged on the shell, the battery cell assembly is accommodated in the shell and comprises a conductive part electrically connected with the first pole, the conductive part comprises a plurality of tabs which are arranged in a stacked manner and connected in a folded manner, and the first pole is electrically connected with a plurality of conductive parts; the first pole is provided with a plurality of through holes, and each through hole is provided with at least one conductive part in a penetrating mode.

Description

Battery cells, batteries and electrical devices

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application is based on the Chinese patent application with application number 202321139017.6 and application date 2023-05-11, and claims the priority of the above-mentioned Chinese patent application. The entire content of the above-mentioned Chinese patent application is hereby introduced into this application as a reference. Technical Field

[0003] The present application relates to the field of battery technology, and in particular to a battery cell, a battery, and an electrical device. Background Art

[0004] New energy vehicles have experienced rapid growth in recent years. Batteries, as the power source of electric vehicles, play an irreplaceable and important role. Batteries typically consist of multiple cells, but the energy density of these cells is currently difficult to increase, hindering vehicle range.

[0005] Summary of the Invention

[0006] The embodiments of the present application provide a battery cell, a battery, and an electrical device, which are beneficial to improving the energy density of the battery cell.

[0007] In the first aspect, an embodiment of the present application provides a battery cell, which includes: a shell assembly and a cell assembly, the shell assembly includes a shell and a first pole arranged in the shell, the cell assembly is accommodated in the shell and includes a conductive part electrically connected to the first pole, the conductive part includes a plurality of pole tabs that are stacked and connected together, the first pole is electrically connected to the plurality of conductive parts, and the first pole has a plurality of through-holes, each of which is respectively perforated with at least one conductive part.

[0008] In the above technical solution, since the first electrode is electrically connected to multiple conductive portions, the number of conductive portions of the same polarity in the battery cell is multiple, and each conductive portion includes multiple tabs arranged in a stacked and folded manner. This can reduce the number of tabs included in each conductive portion, thereby reducing the folded height of the multiple tabs in each conductive portion, thereby reducing the size occupied by each conductive portion in the housing along the direction in which the tabs extend. When the size of the housing is constant, the space available for the active material coating portion in the direction in which the tabs extend can be increased, thereby facilitating an increase in the energy density of the battery cell. Furthermore, by providing the first electrode with multiple conductive portions electrically connected, and the first electrode having multiple through-holes, each through-hole having at least one conductive portion, the conductive portions electrically connected to the first electrode can be at least partially retracted within the first electrode to occupy the space in the first electrode, thereby further reducing the space occupied by the conductive portions within the housing. Moreover, compared to a solution in which all conductive portions electrically connected to the first electrode are concentrated and extended through a single through-hole, the present application facilitates reducing the size of each through-hole, thereby alleviating the adverse effect of a larger through-hole size on the structural strength of the first electrode. In addition, the provision of multiple through-holes also allows the conductive part to flexibly select the through-holes. For example, when the distances between the multiple through-holes and the conductive part are different, the conductive part can choose to extend from a relatively close through-hole, which is beneficial to shortening the extension length of the conductive part and further reducing the space occupied by the conductive part in the shell. For another example, the conductive part can choose to extend from a relatively small number of through-holes to facilitate assembly, improve the problem of the large size of individual through-holes, and improve the structural strength of the first pole.

[0009] In some embodiments, the battery cell assembly includes at least one electrode assembly, each electrode assembly includes a conductive portion, and a through-hole is provided on the first pole at a position corresponding to each electrode assembly.

[0010] In the above technical solution, the conductive portion extending from the electrode assembly can pass through the perforation provided for that electrode assembly, thereby effectively shortening the extension length of the conductive portion within the housing and reducing the space occupied by the conductive portion within the housing, thereby facilitating an increase in the energy density of the battery cell. Alternatively, some conductive portions can be optionally passed through the perforation provided for an adjacent electrode assembly, thereby increasing manufacturing flexibility.

[0011] In some embodiments, the electrode assembly includes an active material coating portion, the conductive portion includes a gathering portion and a connecting portion, the gathering portion is formed by gathering a plurality of pole tabs, the connecting portion is formed by gathering and connecting a plurality of pole tabs, the connecting portion is used to electrically connect with the first pole, the gathering portion connects the connecting portion and the active material coating portion, and the connection position between the gathering portion and the connecting portion is a connecting root; the first pole is provided with a perforation at a position corresponding to at least one connecting root in each electrode assembly.

[0012] In the above technical solution, at least one conductive part can pass through the perforation corresponding to its connection root, thereby shortening the extension length of the connection part in the conductive part within the shell, reducing the space occupied by the conductive part within the shell, and facilitating improving the energy density of the battery cell.

[0013] In some embodiments, a through hole is provided in a middle region of the first pole corresponding to each electrode assembly in a thickness direction.

[0014] In the above technical solution, by arranging the perforation relative to the electrode assembly in the center or close to the center, the conductive part on the electrode assembly can be relatively close to the centrally set perforation no matter where it extends from or how many it extends, so that the conductive part will not extend too long before passing through the perforation, thereby better reducing the space occupied by each conductive part in the shell.

[0015] In some embodiments, the electrode assembly includes an active material coating portion, the conductive portion includes a gathered portion and a connecting portion, the gathered portion is formed by gathering a plurality of pole tabs, the connecting portion is formed by gathering and connecting a plurality of pole tabs, the connecting portion is used to electrically connect to the first pole, the gathered portion connects the connecting portion and the active material coating portion, and the connection position between the gathered portion and the connecting portion is a connecting root; at least one connecting root in the electrode assembly corresponds to the middle area in the thickness direction of the electrode assembly.

[0016] In the above technical solution, by folding the tab of at least one conductive portion of the electrode assembly at or near the center, the collapsed height of the conductive portion is reduced, thereby reducing the footprint of the conductive portion within the housing along the direction in which the tab extends, thereby improving the energy density of the battery cell. Furthermore, the distance between the centrally collapsed conductive portion and the corresponding perforations of the corresponding electrode assembly can be relatively close, so that the conductive portion does not extend too far before passing through the perforations, thereby effectively reducing the space occupied by each conductive portion within the housing.

[0017] In some embodiments, the battery cell assembly includes at least one combination, each combination includes two electrode assemblies, each electrode assembly in each combination includes multiple conductive parts of the same polarity, and at least two conductive parts of the same polarity belonging to different electrode assemblies and arranged adjacently in each combination are connected and arranged.

[0018] In the above technical solution, by connecting and setting at least two conductive parts of the same polarity that belong to different electrode assemblies and are arranged adjacent to each other in each combination, the number and the retraction height of the conductive parts can be taken into account, which is beneficial to prevent the number of perforations from being too many, ensure the structural strength of the first pole, and reduce the space occupied by the conductive part in the direction of the pole ear extending.

[0019] In some embodiments, the battery cell assembly includes at least one electrode assembly, each electrode assembly includes at least one conductive part, the electrode assembly includes an active material coating part, the conductive part includes a folded part and a connecting part, the folded part is formed by folding a plurality of pole tabs, the connecting part is formed by folding and connecting a plurality of pole tabs, the connecting part is used to electrically connect to the first pole, the folded part connects the connecting part and the active material coating part, the connection position between the folded part and the connecting part is the connecting root, and the conductive part is passed through a through-hole closest to the corresponding connecting root.

[0020] In the above technical solution, by respectively passing each conductive part through a through-hole closest to its connection root, the conductive part selects a relatively close through-hole to extend out, which is beneficial to shortening the extension length of the conductive part in the shell before passing through the through-hole, reducing the space occupied by the conductive part in the shell, and is beneficial to improving the energy density of the battery cell. It is also beneficial to reduce the redundancy of the conductive part in the shell, effectively reducing the risk of short circuit between the redundancy of the conductive part in the shell and the active material coating part, and improving the reliability of the battery cell.

[0021] In some embodiments, a through hole is provided on the first pole at a position corresponding to the connection root of each conductive portion.

[0022] In the above technical solution, each conductive part can be passed through the corresponding perforation at its connecting root, thereby shortening the extension length of each conductive part's connecting portion within the housing, reducing the space occupied by each conductive part within the housing, and further improving the energy density of the battery cell. Furthermore, this helps reduce the redundancy of each conductive part within the housing, more effectively reducing the risk of redundant conductive parts within the housing shorting with the active material coating, thereby improving the reliability of the battery cell.

[0023] In some embodiments, the perforation is a long strip hole, and the conductive part includes a connecting part penetrated through the perforation. The connecting part is sheet-shaped and the length direction of the part located in the perforation is consistent with the length direction of the perforation, and the width direction of the perforation is consistent with the thickness direction of the connecting part.

[0024] In the above technical solution, by setting the perforation to be a long strip that roughly matches the shape of the connecting portion of the conductive part, the connecting portion of the conductive part can easily pass through the perforation, and after the conductive part passes through the perforation, the space left in the perforation can be relatively small, which is beneficial to reducing the size of the perforation to facilitate subsequent sealing of the perforation and to improve the structural strength of the first pole.

[0025] In some embodiments, a spacing direction of the plurality of through-holes on the first pole is different from a length direction of the through-holes.

[0026] In the above technical solution, since the multiple through-holes on the first pole can be arranged at intervals along a direction intersecting the length direction of the through-holes, the space occupied by the multiple through-holes on the first pole in the length direction of the through-holes can be reduced, which is conducive to reducing the size of the first pole in the length direction of the through-holes.

[0027] In some embodiments, the conductive portion is composed of a plurality of tabs, and the tabs are welded to the first pole; or, the conductive portion further includes a transition piece, and the tabs are connected to the first pole via the transition piece.

[0028] In the above technical solution, when the conductive portion is composed of multiple tabs and the tabs are welded to the first pole, the structure and processing of the conductive portion can be simplified. When the conductive portion also includes an adapter plate, and the tabs are connected to the first pole via the adapter plate, the adapter plate can be welded to the first pole in a manner that avoids the connection with the tabs. This ensures a secure weld between the adapter plate and the first pole and reduces the risk of weld cracking.

[0029] In some embodiments, the first pole has a receiving groove communicating with the through hole, and a portion of the conductive portion passes through the through hole and is received in the receiving groove.

[0030] In the above technical solution, since the first electrode is provided with a receiving groove, the weight of the first electrode can be reduced, which is beneficial to improving the weight energy density of the battery cell. In addition, by partially accommodating the conductive part in the receiving groove, the space occupied in the shell is reduced, which is beneficial to increasing the volume of the active material coating part and improving the volume energy density of the battery cell.

[0031] In some embodiments, the first pole includes an end wall and a side wall, the end wall is located on the side of the side wall close to the interior of the shell, the end wall and the side wall are arranged to form a receiving groove, the groove of the receiving groove is open to the side away from the interior of the shell, and multiple through-holes are opened on the end wall to connect the receiving groove with the interior of the shell, and the outer end of the conductive part extends into the receiving groove through the through-hole and is connected to the end wall.

[0032] In the above technical solution, since the receiving groove is open toward the side of the first pole away from the interior of the shell, it is convenient to weld the conductive part and the end wall through the receiving groove from the outside of the first pole, that is, the side of the first pole away from the active material coating part, and it is also convenient to perform external welding of the first pole and the conductive part through the receiving groove, which is convenient for the processing and manufacturing of the battery cell and can save the processing and manufacturing costs.

[0033] In some embodiments, the outer ends of the plurality of conductive portions connected to the end wall are stacked and connected on the end wall; or, the outer ends of the plurality of conductive portions connected to the end wall are spaced apart on the end wall.

[0034] In the above technical solution, when the outer ends of the multiple conductive portions connected to the end wall are stacked and connected on the end wall, it is beneficial to the miniaturization design of the first terminal. When the outer ends of the multiple conductive portions connected to the end wall are spaced apart on the end wall, it is beneficial to improve the reliability of the electrical connection between each conductive portion and the first terminal.

[0035] In some embodiments, the housing assembly further includes a pole cover plate, the pole cover plate cooperates with the first pole and covers the notch, and the pole cover plate is electrically connected to the first pole.

[0036] In the above technical solution, by providing a pole cover plate to close the notch of the receiving tank, the electrolyte in the shell can be prevented from leaking from the notch of the receiving tank. Moreover, since the pole cover plate closes the notch of the receiving tank and is electrically connected to the first pole, the pole cover plate can be used to easily realize indirect electrical connection between the first pole and the busbar component, and it is beneficial to increase the connection area of ​​the electrical connection, thereby helping to reduce the resistance of the electrical connection.

[0037] In some embodiments, a plurality of poles are provided on the housing, wherein at least one pole is a first pole.

[0038] In the above technical solution, by setting at least one of all the poles of the shell assembly as the first pole, a part of the entire battery cell can be the first pole with multiple perforations, or all of it can be the first pole with multiple perforations, so that it can be flexibly selected and matched according to manufacturing requirements, cost requirements, etc.

[0039] In a second aspect, an embodiment of the present application further provides a battery comprising the above-mentioned battery cell.

[0040] In the above technical solution, since the battery is provided with the above-mentioned battery cells, the energy density of the battery cells can be improved, which is beneficial to improving the energy density of the battery.

[0041] In a third aspect, an embodiment of the present application further provides an electrical device comprising the above-mentioned battery.

[0042] In the above technical solution, since the electrical device is provided with the above-mentioned battery, the energy density of the battery can be improved, which is beneficial to increasing the service life of the electrical device. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] 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.

[0044] FIG1 is a schematic diagram of a structure in which a power-consuming device provided by some embodiments of the present application is a vehicle;

[0045] FIG2 is an exploded view of a battery cell structure used in a battery according to some embodiments of the present application;

[0046] FIG3 is a perspective view of a battery cell provided in some embodiments of the present application;

[0047] FIG4 is an exploded view of a portion of the battery cell shown in FIG3 ;

[0048] FIG5 is a partial enlarged view of point A shown in FIG4 ;

[0049] FIG6 is an orthographic view of the battery cell shown in FIG3 ;

[0050] FIG7 is a cross-sectional view along line BB in FIG6 ;

[0051] FIG8 is a partial enlarged view of point C shown in FIG7;

[0052] FIG9 is a partial cross-sectional view of a battery cell provided in some embodiments of the present application;

[0053] FIG10 is a partial cross-sectional view of a battery cell provided in some embodiments of the present application;

[0054] FIG11 is a perspective view of a first pole provided in some embodiments of the present application;

[0055] FIG12 is an orthographic projection view of the first pole shown in FIG11;

[0056] FIG13 is a cross-sectional view along line DD in FIG12;

[0057] FIG14 is an orthographic view of a battery cell provided in some embodiments of the present application;

[0058] FIG15 is a partial enlarged view of point E shown in FIG14 ;

[0059] FIG16 is a partial cross-sectional view of a battery cell provided in some embodiments of the present application.

[0060] Figure markings: electrical device 1000; battery 100; controller 200; motor 300; housing 20; first housing 201; second housing 202; battery cell 10; housing assembly 1; housing 11; first pole 12; perforation 121; end wall 122; side wall 123; accommodating groove 124; notch 1241; pole outer end face 125; pole cover 13; cell assembly 2; electrode assembly 20; middle area 201; active material coating portion 21; conductive portion 22; pole ear sheet 220; gathering portion 221; connecting portion 222; connecting root 223; outer end portion 224 of the conductive portion; adapter sheet 225; first direction Z; second direction X; third direction Y. DETAILED DESCRIPTION

[0061] 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.

[0062] 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.

[0063] 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.

[0064] 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.

[0065] In the embodiments of this application, the same reference numerals represent the same components, and for the sake of brevity, detailed descriptions of the same components in different embodiments are omitted. It should be understood that the thickness, length, width, and other dimensions of the various components in the embodiments of this application, as well as the overall thickness, length, width, and other dimensions of the integrated device shown in the drawings are merely illustrative and should not constitute any limitation on this application.

[0066] The term "plurality" used in this application refers to two or more (including two).

[0067] In this application, battery cells may include lithium-ion secondary batteries, lithium-ion primary batteries, lithium-sulfur batteries, sodium-lithium-ion batteries, sodium-ion batteries, or magnesium-ion batteries, etc., and the embodiments of this application do not limit this. 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 based on the packaging method: cylindrical battery cells, prismatic battery cells, and soft-pack battery cells, and the embodiments of this application do not limit this.

[0068] For example, a battery cell typically includes a housing, a cell assembly, and an electrolyte. The housing houses the cell assembly and electrolyte. The housing is provided with electrodes, which are typically multiple and include at least one positive electrode and at least one negative electrode. The cell assembly includes one or more electrode assemblies, which are formed by stacking or winding positive and negative electrode sheets and separators.

[0069] The positive electrode sheet generally includes a positive electrode current collector and a positive electrode active material layer. The positive electrode active material layer is directly or indirectly coated on the positive electrode current collector. The positive electrode current collector not coated with the positive electrode active material layer protrudes from the positive electrode current collector coated with the positive electrode active material layer. The positive electrode current collector not coated with the positive electrode active material layer serves as a positive electrode tab. Multiple positive electrode tabs are stacked together and electrically connected to the positive electrode column. For example, the stacked multiple positive electrode tabs can be directly welded to the positive electrode column to form an electrical connection. Alternatively, the battery cell assembly may further include a positive electrode adapter. The stacked multiple positive electrode tabs are welded to one end of the positive electrode adapter, and the other end of the positive electrode adapter is welded to the positive electrode column to form an electrical connection between the positive electrode tab and the positive electrode column.

[0070] A negative electrode sheet generally includes a negative electrode current collector and a negative electrode active material layer. The negative electrode active material layer is directly or indirectly coated on the negative electrode current collector. The negative electrode current collector not coated with the negative electrode active material layer protrudes from the negative electrode current collector coated with the negative electrode active material layer. The negative electrode current collector not coated with the negative electrode active material layer serves as a negative electrode tab. Multiple negative electrode tabs are stacked together and electrically connected to the negative electrode post. For example, the stacked multiple negative electrode tabs can be directly welded to the negative electrode post to form an electrical connection. Alternatively, the battery cell assembly may further include a negative electrode adapter. The stacked multiple negative electrode tabs are welded to one end of the negative electrode adapter, and the other end of the negative electrode adapter is welded to the negative electrode post to form an electrical connection between the negative electrode tab and the negative electrode post.

[0071] The material of the isolation film is not limited, and can be, for example, polypropylene or polyethylene.

[0072] At the same time, battery cells primarily rely on the movement of metal ions between the positive and negative electrodes to operate. Taking lithium-ion batteries as an example, the positive electrode current collector can be made of aluminum, the positive electrode active material layer can be made of lithium cobalt oxide, lithium iron phosphate, ternary lithium, or lithium manganese oxide, etc. The negative electrode current collector can be made of copper, and the negative electrode active material layer can be made of carbon or silicon, etc. During the charge and discharge process, Li+ is intercalated and deintercalated back and forth between the two electrodes: during charging, Li+ is deintercalated from the positive electrode and intercalated into the negative electrode through the electrolyte, leaving the negative electrode in a lithium-rich state; during discharge, the opposite occurs.

[0073] 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 be a battery module or battery pack. A battery module generally includes multiple battery cells. A battery pack generally includes a casing for enclosing one or more battery cells or one or more battery modules. The casing prevents liquids or other foreign matter from affecting the charging or discharging of the battery cells.

[0074] In a battery, multiple battery cells can be connected in series, in parallel, or in a hybrid configuration. A hybrid configuration refers to a combination of series and parallel connections. Multiple battery cells can be directly connected in series, in parallel, or in a hybrid configuration, and then the entire battery cell structure is housed within a housing. Alternatively, a battery can be constructed by first connecting multiple battery cells in series, in parallel, or in a hybrid configuration to form a battery module. Multiple battery modules are then connected in series, in parallel, or in a hybrid configuration to form a single unit, which is then housed within a housing.

[0075] In the related art, during the manufacturing of battery cells, active material is coated on the current collector and then cut to obtain a pole piece consisting of a current collector coated with an active material layer (referred to as the active material coating part) and a current collector not coated with the active material layer (referred to as the pole ear piece). Then, the positive and negative pole pieces and the isolation film are stacked or wound in sequence to obtain an electrode assembly. The active material coating part of the electrode assembly is welded to the pole through the conductive part. The conductive part can be a pole ear part formed by stacking and folding pole ear pieces of the same polarity in the electrode assembly to form a pole ear part, or it can be composed of a pole ear part and a transition piece welded to the pole ear part.

[0076] Typically, a battery cell shell is provided with multiple electrode assemblies. When processing the tab portion, the tabs of the same polarity in the multiple electrode assemblies are stacked together. Therefore, the tab portion contains a large number of tabs, and the tab portion formed by the folded connection has a large folded height (wherein the folded height refers to the vertical distance from the starting position of the folded connection of the tab to the active material coating portion, and the direction of this vertical distance is recorded as the tab extension direction). Therefore, the tab portion occupies a large dimension in the shell along the tab extension direction. When the size of the shell is constant, it will affect the space that the active material coating portion can occupy in the tab extension direction, making it difficult to increase the energy density of the battery cell. Moreover, when all the tabs of the same polarity are folded together, the tabs farther from the starting position of the folded connection (i.e., the edge tabs) will be more deformed and the risk of cracking will be greater.

[0077] Based on the above considerations, in order to improve the energy density of the battery cell, the present application designs a battery cell, in which the number of conductive parts of the same polarity in the battery cell is set to multiple, and each conductive part includes multiple tabs arranged in a stacked and folded manner. This can reduce the number of tabs included in each conductive part, and further reduce the folded height of the tabs in each conductive part, thereby reducing the size occupied by each conductive part in the housing along the direction in which the tabs extend. When the size of the housing is constant, the space that can be occupied by the active material coating part in the direction in which the tabs extend can be increased, which is conducive to improving the energy density of the battery cell. Moreover, the deformation of the tabs at the edge of the conductive part can be reduced to a certain extent, reducing the risk of cracking of the tabs.

[0078] In addition, in an embodiment of the present application, a plurality of through-holes are provided on at least one pole, and each through-hole is provided with at least one conductive part electrically connected to the pole, so that the pole can accommodate at least part of the conductive part, so as to further reduce the space occupied by the conductive part in the shell, further increase the space that can be occupied by the active material coating part in the shell, and further increase the energy density of the battery cell. Moreover, the provision of a plurality of through-holes also allows the conductive part to flexibly select the through-holes. For example, when the distances between the plurality of through-holes and the conductive part are different, the conductive part can select a relatively close through-hole to extend out, which is beneficial to shortening the extension length of the conductive part in the shell, so as to further reduce the space occupied by the conductive part in the shell. For another example, the conductive part can also select a relatively small number of through-holes to extend out, so as to facilitate assembly, improve the problem of large individual through-hole sizes, and improve the strength of the pole.

[0079] The present application also provides an electrical device using the battery of the present application as a power source. The electrical device may be, but is not limited to, a mobile phone, a tablet, a laptop computer, an electric toy, an electric tool, a battery-powered vehicle, an electric car, a ship, a spacecraft, etc. The electric toy may include a fixed or mobile electric toy, such as a game console, an electric car toy, an electric ship toy, and an electric airplane toy, etc. The spacecraft may include an airplane, a rocket, a space shuttle, and a spacecraft, etc.

[0080] For the convenience of explanation, the following embodiments take a vehicle as an example of an electrical device to introduce in detail the structures of the electrical device, battery and battery cells of the present application.

[0081] Please refer to Figure 1, which is a schematic structural diagram of a vehicle in which the power-consuming device 1000 provided in some embodiments of the present application is a vehicle. The vehicle can be a fuel vehicle, a gas vehicle or a new energy vehicle, and the new energy vehicle can be a pure electric vehicle, a hybrid vehicle or an extended-range vehicle, etc. The vehicle is provided with a battery 100, and the battery 100 can be arranged at the bottom, head or tail of the vehicle. The battery 100 can be used to power the vehicle, for example, the battery 100 can be used as an operating power source for the vehicle. The vehicle may also include a controller 200 and a motor 300, and the controller 200 is used to control the battery 100 to power the motor 300, for example, for the starting, navigation and working power requirements of the vehicle during driving. In some embodiments of the present application, the battery 100 can not only serve as the operating power source of the vehicle, but also as the driving power source of the vehicle, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle.

[0082] Please refer to Figure 2, which is an exploded view of the structure of the battery cell 10 provided in some embodiments of the present application. The battery 100 includes a housing 20 and a plurality of battery cells 10, and the battery cells 10 are accommodated in the housing 20. The housing 20 is used to provide an assembly space for the battery cells 10, and the housing 20 can adopt a variety of structures. In some embodiments, the housing 20 can include a first housing 201 and a second housing 202, which cover each other and together define an assembly space for accommodating the battery cells 10. The second box body 202 can be a hollow structure with one end open, and the first box body 201 can be a plate-like structure, with the first box body 201 covering the open side of the second box body 202, so that the first box body 201 and the second box body 202 jointly define an assembly space; alternatively, the first box body 201 and the second box body 202 can both be hollow structures with one end open (for example, as shown in FIG. 2 ), with the open side of the first box body 201 covering the open side of the second box body 202. Of course, the box body 20 formed by the first box body 201 and the second box body 202 can have various shapes, such as a cylinder or a rectangular parallelepiped.

[0083] Please refer to Figure 3, which is a schematic diagram of a battery cell 10 provided in some embodiments of the present application. The battery cell 10 is a rectangular parallelepiped, with the width of the battery cell 10 being a first direction Z, the length of the battery cell 10 being a second direction X, and the thickness of the battery cell 10 being a third direction Y. The first direction Z, the second direction X, and the third direction Y are mutually perpendicular. However, this is not limiting. In other embodiments of the present application, the battery cell 10 may also have other shapes, such as a cylinder, a flat body, or a prismatic structure.

[0084] Please refer to Figure 4, which is an exploded view of a portion of the battery cell shown in Figure 3. In the embodiment of the present application, the battery cell 10 includes a housing assembly 1 and a cell assembly 2. The housing assembly 1 includes a housing 11 and a first pole 12 disposed on the housing 11. The cell assembly 2 is accommodated in the housing 11. The shape of the housing 11 is adjusted according to the type of battery cell 10, and the type of battery cell 10 in the embodiment of the present application is not limited. For example, when the battery cell 10 is a square battery, the housing 11 is square. When the battery cell 10 is a cylindrical battery, the housing 11 is cylindrical. The embodiments of the present application are described using the square housing 11 as an example.

[0085] The housing 11 is provided with poles, which are used to electrically connect to the battery cell assembly 2 to ensure normal charging and discharging operations of the battery cell 10. Generally, there are at least two poles, specifically at least one positive pole and at least one negative pole. For example, when there are two poles, one is a positive pole and the other is a negative pole, and the two poles are electrically connected to the positive and negative output positions of the battery cell assembly 2, respectively. For another example, when there are four poles, two can be positive poles and two can be negative poles. In this case, both positive poles are electrically connected to the positive output position of the battery cell assembly 2, and both negative poles are electrically connected to the negative output position of the battery cell assembly 2.

[0086] In an embodiment of the present application, at least one of the multiple poles on the housing 11 is a first pole 12. The first pole 12 can serve as either a positive pole or a negative pole. Referring to Figures 5-8, Figure 5 is a partial enlarged view of point A shown in Figure 4, Figure 6 is an orthographic view of the battery cell 10 shown in Figure 3, Figure 7 is a cross-sectional view along line BB in Figure 6, and Figure 8 is a partial enlarged view of point C shown in Figure 7. The battery cell assembly 2 includes a conductive portion 22. Each first pole 12 is electrically connected to a plurality of conductive portions 22. The first pole 12 has a plurality of through-holes 121, each through-hole 121 having at least one conductive portion 22 therethrough. Thus, the plurality of conductive portions 22 electrically connected to the first pole 12 can be at least partially accommodated within the first pole 12, thereby occupying space within the first pole 12. This saves space occupied by the conductive portion 22 within the housing 11, thereby facilitating an increase in the energy density of the battery cell 10.

[0087] When the shell 11 is provided with multiple poles, all the poles on the shell 11 may be first poles 12 electrically connected to multiple conductive parts 22, or some of the poles on the shell 11 may be first poles 12 electrically connected to multiple conductive parts 22. When some of the poles on the shell 11 are first poles 12 electrically connected to multiple conductive parts 22, the remaining poles on the shell 11 are second poles electrically connected to one conductive part 22 (not shown). Regardless of whether the pole on the shell 11 is the first pole 12 or the second pole, the first pole 12 and the second pole can be electrically connected to the battery cell assembly 2 to ensure the normal charging and discharging process of the battery cell 10. To simplify the description, the following text mainly introduces the case where there are multiple poles on the shell 11, and all the poles are the first pole 12, that is, each pole is electrically connected to multiple conductive parts 22.

[0088] In an embodiment of the present application, the battery cell assembly 2 includes an active material coating portion 21, which is arranged in the shell 11. The active material coating portion 21 is the portion of the battery cell assembly 2 coated with active material, which can assist in the deintercalation of metal ions during the charging and discharging process of the battery cell 10. The conductive portion 22 is a metal structure that electrically connects the active material coating portion 21 and the pole, which is not coated with active material, and both the first pole 12 and the second pole can be electrically connected to the active material coating portion 21 through the conductive portion 22, so that the charging and discharging operations of the battery cell 10 can be carried out.

[0089] It is understood that the active material coating portion 21 is divided into a positive electrode active material coating portion and a negative electrode active material coating portion. The positive electrode active material coating portion includes the portion of the positive electrode current collector coated with the positive electrode active material layer, and the negative electrode active material coating portion includes the portion of the negative electrode current collector coated with the negative electrode active material layer. The conductive portion 22 is divided into a positive electrode conductive portion and a negative electrode conductive portion. The positive electrode conductive portion electrically connects the positive electrode active material coating portion to the positive electrode post, and the negative electrode conductive portion electrically connects the negative electrode active material coating portion to the negative electrode post.

[0090] Referring again to Figures 5 and 8 , in the embodiment of the present application, the conductive portion 22 includes a plurality of tabs 220 stacked and connected. Specifically, the conductive portion 22 includes a gathering portion 221 and a connecting portion 222. The gathering portion 221 is formed by gathering the plurality of tabs 220, while the connecting portion 222 is formed by gathering and connecting the plurality of tabs 220. The gathering portion 221 connects the connecting portion 222 and the active material coating portion 21. In other words, when forming the gathering portion 221, the plurality of tabs 220 are merely brought together (i.e., gathered toward each other) but not connected. However, when forming the connecting portion 222, the plurality of tabs 220 are not only brought together but also connected to form a single structure. For example, the plurality of tabs 220 can be connected to form a single sheet structure by welding (e.g., ultrasonic welding) to form the connecting portion 222. Alternatively, the plurality of tabs 220 can be brought together and connected to form the connecting portion 222 by bonding with a conductive adhesive.

[0091] The connecting portion 222 is used to electrically connect to the first pole 12. That is, the connecting portion 222 can be directly connected to the first pole 12 (for example, as shown in FIG8 ) or indirectly connected (for example, as shown in FIG9 , which is a partial cross-sectional view of a battery cell provided in some embodiments of the present application). In some optional embodiments, such as shown in FIG8 , the conductive portion 22 can be composed only of a plurality of tabs 220. In this case, the tabs 220 can be welded to the first pole 12, thereby simplifying the structure and processing of the conductive portion 22. Alternatively, in some other optional embodiments, such as shown in Figure 9, the conductive part 22 may further include a transfer plate 225 in addition to a plurality of pole tabs 220. The pole tab 220 is connected to the first pole 12 via the transfer plate 225. For example, one end of the transfer plate 225 is welded to the connecting part 222, and the other end of the transfer plate 225 is welded to the first pole 12, so that the plurality of pole tabs 220 are connected to the first pole 12 via the transfer plate 225. At this time, the transfer plate 225 can be welded to the first pole 12 by avoiding the portion connected to the pole tab 220, so that the welding between the transfer plate 222 and the first pole 12 is firm and welding cracking is less likely to occur.

[0092] It is understood that the tabs 220 are divided into positive and negative electrode tabs 220. The positive electrode tabs 220 that need to be gathered together are stacked together and ultrasonically pre-welded to form the positive electrode connection portion 222. This can reduce the gaps between the layers, allowing the multiple fluffy positive electrode tabs 220 to form a sheet structure with a certain degree of rigidity. Similarly, the negative electrode tabs 220 that need to be gathered together are stacked together and ultrasonically pre-welded to form the negative electrode connection portion 222. This can reduce the gaps between the layers, allowing the multiple fluffy negative electrode tabs 220 to form a sheet structure with a certain degree of rigidity. For example, the current collector and the tabs 220 can be a single piece. For example, for the positive electrode tab, it can be an integrally formed aluminum foil, and for the negative electrode tab, it can be an integrally formed copper foil, etc.

[0093] Please refer to Figure 8 again. The connection position between the folding portion 221 and the connecting portion 222 is the connecting root 223. The vertical distance between the connecting root 223 and the active material coating portion 21 is the folding height (for example, the distance H shown in Figure 8). The direction of the vertical distance is recorded as the tab extension direction (for example, the first direction Z shown in Figure 8). In an embodiment of the present application, each first electrode 12 is electrically connected to a plurality of conductive parts 22, that is, the number of conductive parts 22 of the same polarity in the battery cell 10 is multiple, that is, all the positive electrode tabs 220 in the battery cell 10 are retracted and connected to form a plurality of positive electrode connection parts 222, and all the negative electrode tabs 220 in the battery cell 10 are retracted and connected to form a plurality of negative electrode connection parts 222. Since each conductive part 22 includes a plurality of tabs 220 that are stacked and retracted, the number of tabs 220 included in each conductive part 22 can be reduced, and the retracted height of the plurality of tabs 220 in each conductive part 22 can be reduced, thereby reducing the size occupied by each conductive part 22 in the shell 11 along the extension direction of the tab. When the size of the shell 11 is constant, the space that can be occupied by the active material coating part 21 in the extension direction of the tab can be increased, which is beneficial to improving the energy density of the battery cell 10. Moreover, each conductive portion 22 includes a relatively small number of tabs 220 , which can reduce the deformation of the tabs 220 at the edge of the conductive portion 22 to a certain extent, thereby lowering the risk of cracking of the tabs 220 .

[0094] Furthermore, in the embodiment of the present application, the first pole 12 has a plurality of through-holes 121, and each through-hole 121 is provided with at least one conductive portion 22. Compared to a solution in which all conductive portions 22 electrically connected to the first pole 12 are concentrated and extended through a single through-hole 121, the embodiment of the present application is advantageously configured to reduce the size of each through-hole 121, thereby alleviating the adverse effect of a larger through-hole 121 on the structural strength of the first pole 12. Furthermore, the provision of multiple through-holes 121 allows the conductive portion 22 to flexibly select a through-hole 121. For example, when the distances between the multiple through-holes 121 and the conductive portion 22 are different, the conductive portion 22 can extend from a relatively close through-hole 121, thereby shortening the extension length of the conductive portion 22 and further reducing the space occupied by the conductive portion 22 within the housing 11. For another example, the conductive portion 22 can extend from a relatively small number of through-holes 121, thereby facilitating assembly and alleviating the problem of the large size of the individual through-holes 121, thereby improving the structural strength of the first pole 12.

[0095] In the embodiment of the present application, the number of the through-holes 121 on the first pole 12 is not limited, for example, it can be two, three, four, or even more. When the number of the through-holes 121 on the first pole 12 is two, it is beneficial to improve the structural strength of the first pole 12 and can maximize the electrical connection area between the conductive portion 22 and the first pole 12.

[0096] In the embodiment of the present application, the number of conductive portions 22 electrically connected to the first pole 12 and the number of through-holes 121 may be the same or different. The number of conductive portions 22 is greater than or equal to the number of through-holes 121 to ensure that each through-hole 121 is provided with at least one conductive portion 22. For example, when there are two conductive portions 22 electrically connected to the first pole 12, the first pole 12 may have two through-holes 121. For example, when there are three conductive portions 22 electrically connected to the first pole 12, the first pole 12 may have two or three through-holes 121. Providing two through-holes 121 is beneficial for improving the structural strength of the first pole 12 and the electrical connection area with the conductive portion 22.

[0097] For example, when the number of conductive parts 22 electrically connected to the first pole 12 is four, the number of through-holes 121 on the first pole 12 can be two, three, or four. When two through-holes 121 are provided, it is beneficial to improve the structural strength of the first pole 12 and the electrical connection area with the conductive part 22. When four through-holes 121 are provided, the space occupied by the conductive part 22 in the shell 11 can be fully reduced, which is beneficial to improve the energy density of the battery cell 10.

[0098] Please refer to Figures 4, 7 and 8 again. In some embodiments of the present application, the battery cell assembly 2 includes at least one electrode assembly 20, that is, the number of electrode assemblies 20 included in the battery cell assembly 2 is one or more, and each electrode assembly 20 includes a conductive portion 22. For example, illustratively, when there is one electrode assembly 20, the electrode assembly 20 includes multiple conductive portions 22 electrically connected to each first pole 12. For another example, illustratively, when there are multiple electrode assemblies 20, each electrode assembly 20 includes at least one conductive portion 22 electrically connected to each first pole 12, so that multiple electrode assemblies 20 can have multiple conductive portions 22 electrically connected to the first pole 12.

[0099] In the embodiment of the present application, a through-hole 121 is provided on the first pole 12 at a position corresponding to each electrode assembly 20. It is worth noting that the electrode assembly 20 on which the orthographic projection of the through-hole 121 along the direction in which the tab extends falls indicates the corresponding electrode assembly 20 position of the through-hole 121. In the embodiment of the present application, for any electrode assembly 20, there is at least one through-hole 121 whose orthographic projection along the direction in which the tab extends falls, that is, the first pole 12 is provided with at least one through-hole 121 at a position corresponding to each electrode assembly 20.

[0100] In this way, the conductive part 22 extending from the electrode assembly 20 can pass through the perforation 121 set corresponding to the electrode assembly 20, so as to better shorten the extension length of the connecting part 222 in the conductive part 22 in the shell 11, reduce the space occupied by the conductive part 22 in the shell 11, and thus help to improve the energy density of the battery cell 10.

[0101] However, the present application is not limited to this. In other embodiments of the present application, when there is not enough space in the through-hole 121 corresponding to a certain electrode component 20, or when a certain electrode component 20 has a large number of conductive parts 22 of the same polarity extending therefrom, some of the multiple conductive parts 22 close to the adjacent electrode component 20 can also be passed through the through-hole 121 corresponding to the adjacent electrode component 20.

[0102] Please refer to Figure 8 again. For example, when a through-hole 121 is provided on the first pole 12 at a position corresponding to each electrode assembly 20, the first pole 12 is provided with a through-hole 121 at a position corresponding to at least one connection root 223 in each electrode assembly 20. That is, the orthographic projection of the connection root 223 of at least one conductive portion 22 in each electrode assembly 20 along the direction in which the tab extends falls within the through-hole 121. As a result, the conductive portion 22 can pass through the through-hole 121 corresponding to its connection root 223, thereby shortening the extension length of the connection portion 222 of the conductive portion 22 within the housing 11 and reducing the space occupied by the conductive portion 22 within the housing 11, which is beneficial for improving the energy density of the battery cell 10. Moreover, this helps to reduce the redundancy of the conductive portion 22 within the housing 11, reducing the risk of the redundant conductive portion 22 within the housing 11 shorting the active material coating portion 21.

[0103] Referring again to Figure 8 , when the first terminal 12 is provided with a perforation 121 at a position corresponding to each connection root 223 in each electrode assembly 20, the extension length of the connection portion 222 of each conductive portion 22 within the housing 11 can be shortened, reducing the space occupied by each conductive portion 22 within the housing 11, which is conducive to further improving the energy density of the battery cell 10. Furthermore, this helps to reduce the redundancy of each conductive portion 22 within the housing 11, more effectively reducing the risk of redundant conductive portions 22 within the housing 11 shorting the active material coating portion 21, and improving the reliability of the battery cell 10.

[0104] In some embodiments of the present application, referring again to FIG. 8 , the first electrode column 12 is provided with a through-hole 121 in the middle region 201 in the thickness direction of each electrode assembly 20. That is, for any electrode assembly 20, the orthographic projection of at least one through-hole 121 along the direction in which the tab extends falls within the middle region 201 of the corresponding electrode assembly 20. In the present application, the term "middle region 201 in the thickness direction of the electrode assembly 20" is to be understood in a broad sense, referring to the region between 1 / 3 and 2 / 3 of the thickness of the electrode assembly 20 along the thickness direction.

[0105] In this way, by arranging the through-hole 121 in the center or nearly in the center relative to the electrode assembly 20, the conductive part 22 on the electrode assembly 20 can be relatively close to the centrally arranged through-hole 121 no matter where it extends from or how many it extends to, so that the conductive part 22 will not extend too long before passing through the through-hole 121, thereby better reducing the space occupied by each conductive part 22 in the shell 11.

[0106] Referring again to FIG. 8 , when a through-hole 121 is provided on the first electrode post 12 at a position corresponding to each electrode assembly 20, illustratively, the connection root 223 of at least one conductive portion 22 in the electrode assembly 20 corresponds to the middle region 201 in the thickness direction of the electrode assembly 20. In other words, for any electrode assembly 20, the orthographic projection of at least one connection root 223 along the direction in which the tab extends falls within the middle region 201 of the corresponding electrode assembly 20.

[0107] For example, when the connection root 223 of the conductive part 22 corresponds to the middle area 201 in the thickness direction of the electrode assembly 20, the minimum folded height H of the conductive part 22 can be 1 / 2 of the product of the number of pole tabs 220 included in the conductive part 22 and the thickness of each pole tab 220.

[0108] Thus, by folding the tabs 220 of the conductive portion 22 in the electrode assembly 20 in the center or nearly in the center, the folded height of the conductive portion 22 is reduced, thereby reducing the size occupied by the conductive portion 22 in the direction of tab extension within the housing 11, which is beneficial for increasing the space available for the active material coating portion 21 in the direction of tab extension, and thus improving the energy density of the battery cell 10. Moreover, the distance between the conductive portion 22 centered or nearly folded in the center and each through-hole 121 corresponding to the corresponding electrode assembly 20 can be relatively close, so that the conductive portion 22 does not extend too long before passing through the through-hole 121, thereby effectively reducing the space occupied by each conductive portion 22 within the housing 11.

[0109] Furthermore, when the connection root 223 of the conductive part 22 in the electrode assembly 20 corresponds to the middle area 201 in the thickness direction of the electrode assembly 20, and the first pole 12 is provided with a through-hole 121 corresponding to the connection root 223 position of each conductive part 22, the first pole 12 is provided with a through-hole 121 corresponding to the middle area 201 in the thickness direction of each electrode assembly 20, which is more conducive to reducing the distance from the conductive part 22 to the through-hole 121, shortening the extension length of the conductive part 22 in the shell 11 before passing through the through-hole 121, thereby better reducing the space occupied by the conductive part 22 in the shell 11.

[0110] Please refer to Figure 10, which is a partial cross-sectional view of a battery cell 10 provided in some embodiments of the present application. In some embodiments of the present application, the battery cell assembly 2 includes at least one combination, each combination includes two electrode assemblies 20, and each electrode assembly 20 in each combination includes multiple conductive parts 22 of the same polarity, and at least two conductive parts 22 of the same polarity belonging to different electrode assemblies 20 and arranged adjacently in each combination are connected and arranged.

[0111] For example, the two electrode assemblies 20 shown in Figure 10 are a combination, the electrode assembly 20 on the left includes two positive conductive parts 22, and the electrode assembly 20 on the right also includes two positive conductive parts 22. The positive conductive part 22 of the two positive conductive parts 22 of the electrode assembly 20 on the left is close to the right side, and the positive conductive part 22 of the two positive conductive parts 22 of the electrode assembly 20 on the right is connected to the positive conductive part 22 of the two positive conductive parts 22 of the electrode assembly 20 on the right is close to the left side.

[0112] Therefore, if each electrode assembly 20 extends two positive electrode conductive parts 22, and the two electrode assemblies 20 have a total of four independent positive electrode conductive parts 22, then four through-holes 121 need to be opened on the first pole 12 of the positive electrode. Compared with this scheme, the above embodiment connects two of the positive electrode conductive parts 22, and only three through-holes 121 need to be opened on the first pole 12 of the positive electrode, thereby reducing the number of independent conductive parts 22 included in the combination to a certain extent, and further reducing the number of through-holes 121 on the first pole 12, thereby improving the structural strength of the first pole 12 and improving the assembly efficiency. However, if the thickness of the two electrode assemblies 20 is relatively large, and only one positive conductive portion 22 is extended from each electrode assembly 20, the number of pole tabs 220 included in the positive conductive portion 22 of each electrode assembly 20 is relatively large, and the folding height of the conductive portion 22 in the direction of the pole tab extension is relatively high, and the space occupied is relatively large. Compared with this solution, the above embodiment can reduce the number of pole tabs 220 included in each conductive portion 22 to a certain extent by extending two positive conductive portions 22 from each electrode assembly 20, thereby reducing the space occupied by each conductive portion 22 in the direction of the pole tab extension.

[0113] Therefore, in the above technical solution, by connecting and setting at least two conductive parts of the same polarity that belong to different electrode assemblies 20 and are arranged adjacent to each other in each combination, the number and the folding height of the conductive parts 22 can be taken into account, which is beneficial to prevent the number of perforations 121 from being too many, ensuring the structural strength of the first pole 12, and reducing the space occupied by the conductive part 22 in the shell 11 in the direction of the pole ear extension.

[0114] Please refer to Figure 8 again. In some embodiments of the present application, the conductive portion 22 is inserted into a through-hole 121 closest to the corresponding connecting root 223. In this way, by inserting each conductive portion 22 into a through-hole 121 closest to its connecting root 223, the conductive portion 22 is allowed to extend from a relatively close through-hole 121. This helps shorten the extension length of the conductive portion 22 in the housing 11 before passing through the through-hole 121, reduces the space occupied by the conductive portion 22 in the housing 11, and helps improve the energy density of the battery cell 10. It also helps reduce the redundancy of the conductive portion 22 in the housing 11, effectively reducing the risk of the redundancy of the conductive portion 22 in the housing 11 and the risk of short circuit between the active material coating portion 21 and the conductive portion 22, thereby improving the reliability of the battery cell 10.

[0115] Referring again to Figure 8 , when a through-hole 121 is provided at the position of each connecting root 223 of the first terminal 12, each conductive portion 22 can pass through the through-hole 121 corresponding to its connecting root 223 at a shorter distance, thereby further shortening the extension length of the connecting portion 222 of each conductive portion 22 within the housing 11 and reducing the space occupied by each conductive portion 22 within the housing 11, which helps further improve the energy density of the battery cell 10. Furthermore, this helps reduce the redundancy of each conductive portion 22 within the housing 11, more effectively reducing the risk of redundant conductive portions 22 within the housing 11 shorting the active material coating portion 21, and improving the reliability of the battery cell 10.

[0116] Please refer to Figures 11-15. Figure 11 is a perspective view of a first electrode 12 according to some embodiments of the present application. Figure 12 is an orthographic view of the first electrode 12 shown in Figure 11. Figure 13 is a cross-sectional view taken along line DD in Figure 12. Figure 14 is an orthographic view of a battery cell 10 according to some embodiments of the present application. Figure 15 is a partial enlarged view of point E shown in Figure 14. In some embodiments of the present application, the through-hole 121 is an elongated hole. The conductive portion 22 includes a connecting portion 222 that penetrates the through-hole 121. The connecting portion 222 is sheet-shaped. The length direction of the portion of the connecting portion 222 located within the through-hole 121 is consistent with the length direction of the through-hole 121 (e.g., the second direction X shown in Figure 15). The width direction of the through-hole 121 (e.g., the third direction Y shown in Figure 15) is consistent with the thickness direction of the connecting portion 222.

[0117] Therefore, by setting the through-hole 121 to be a long strip that roughly matches the shape of the connecting portion 222 of the conductive portion 22, the connecting portion 222 of the conductive portion 22 can easily pass through the through-hole 121, and after the conductive portion 22 passes through the through-hole 121, the space left in the through-hole 121 can be relatively small, which is beneficial to reducing the size of the through-hole 121, so as to facilitate the subsequent sealing of the through-hole 121, and is beneficial to improving the structural strength of the first pole 12.

[0118] Referring again to FIG. 12 and FIG. 15 , for example, the spacing direction of the plurality of through-holes 121 on the first pole 12 (e.g., the third direction Y shown in FIG. 15 ) is different from the length direction of the through-hole 121 (e.g., the second direction X shown in FIG. 15 ), that is, the spacing direction of the plurality of through-holes 121 on the first pole 12 intersects the length direction of the through-hole 121 at an angle. Thus, the plurality of through-holes 121 can be spaced apart along a direction intersecting the length direction of the through-hole 121, thereby reducing the space occupied by the plurality of through-holes 121 in the length direction of the through-hole 121 on the first pole 12, facilitating a reduction in the size of the first pole 12 in the length direction of the through-hole 121 and facilitating a miniaturized design of the first pole 12. For example, the plurality of through-holes 121 can be spaced apart along the width direction of the through-hole 121 (e.g., the third direction Y shown in FIG. 15 ), thereby further reducing the space occupied by the through-hole 121 in the first pole 12 and further facilitating a miniaturized design of the first pole 12.

[0119] Referring again to FIG. 15 , illustratively, the length L1 of the through-hole 121 is greater than or equal to 1.1 times the length a of the portion of the connecting portion 222 located within the through-hole 121, and less than or equal to the sum of the length a of the portion of the connecting portion 222 located within the through-hole 121 and 22 mm, i.e., 1.1a ≤ L1 ≤ a + 22 mm. Thus, the width L2 of the through-hole 121 is not too small, allowing the conductive portion 22 to pass smoothly through the through-hole 121, and the width L2 of the through-hole 121 is not too large, reducing the gap between the conductive portion 22 and the through-hole 121 after mating, thereby facilitating sealing and improving the structural strength of the first pole 12. Alternatively, the size and cost of the first pole 12 can be reduced while maintaining equivalent structural strength.

[0120] Specifically, the length a and the length L1 can be measured by cutting a cross section of the sample and then using a two-dimensional projection measuring instrument or CT scanning (Computed Tomography).

[0121] Experimental verification shows that when length a is 20 mm and length L1 is 1.09a, or 21.8 mm, the manufacturing misalignment tolerance of the connecting portion 222 is 4 mm, which poses a risk of interference with the edge of the through-hole 121 during insertion. Furthermore, when length a is 20 mm and length L1 is a+23 mm, or 43 mm, the size of the first pole 12 needs to be increased, resulting in higher material costs and lower structural strength of the first pole 12. When length a is 20 mm and length L1 is approximately 33.8 mm, not only does it facilitate assembly with the through-hole 121, but it also reduces the size of the first pole 12, saving material costs and improving its structural strength.

[0122] Please refer again to FIG. 15 , in conjunction with FIG. 16 , which is a partial cross-sectional view of a battery cell 10 provided in some embodiments of the present application. For example, the width L2 of the through-hole 121 is greater than or equal to 1.1 times the total thickness b of all connecting portions 222 located within the through-hole 121 , and less than or equal to the sum of the total thickness b of all connecting portions 222 located within the through-hole 121 and 7 mm, i.e., 1.1b ≤ L2 ≤ b + 7 mm. Thus, the width L2 of the through-hole 121 is not too small, allowing the conductive portion 22 to pass smoothly through the through-hole 121 , and the width L2 of the through-hole 121 is not too large, reducing the gap between the conductive portion 22 and the through-hole 121 after mating, facilitating sealing, and facilitating improved structural strength of the first terminal 12 , or, in other words, reducing the size and cost of the first terminal 12 while maintaining equivalent structural strength.

[0123] Specifically, the length b and the length L2 can be measured by cutting a cross section of the sample and then using a two-dimensional projection measuring instrument or CT scanning (Computed Tomography).

[0124] Experimental verification shows that when the length b is 0.6 mm and the length L2 is 1.09b, or 0.654 mm, the positional accuracy of the connecting portion 222 and the positional accuracy of the through-hole 121 is greater than 0.2 mm, which poses a risk of interference with the edge of the through-hole 121 during insertion. Furthermore, when the length b is 0.6 mm and the length L2 is b+7.1 mm, or 7.7 mm, the size of the first pole 12 needs to be increased, resulting in higher material costs and lower structural strength of the first pole 12. When the length b is 0.6 mm and the length L2 is approximately 3 mm, not only is assembly with the through-hole 121 facilitated, but the size of the first pole 12 can also be reduced, saving material costs and improving the structural strength of the first pole 12.

[0125] Please refer to Figure 8 again. In some embodiments of the present application, the first pole 12 has a receiving groove 124 connected to the perforation 121, and a portion of the conductive part 22 passes through the perforation 121 and is received in the receiving groove 124. It can be understood that the receiving groove 124 is a groove body, and the groove body is a groove-shaped structure with a certain depth. In the above technical solution, since the first pole 12 is provided with the receiving groove 124, the weight of the first pole 12 can be reduced, which is beneficial to improving the weight energy density of the battery cell 10, and by partially receiving the conductive part 22 in the receiving groove 124, the space occupied in the shell 11 is reduced, which is beneficial to increase the volume of the active material coating part 21, and is beneficial to improving the volume energy density of the battery cell 10.

[0126] Please refer to Figure 8 again. For example, the first pole 12 includes an end wall 122 and a side wall 123. The end wall 122 is located on the side of the side wall 123 close to the interior of the shell 11. The end wall 122 and the side wall 123 are arranged to form a receiving groove 124. The notch 1241 of the receiving groove 124 is open to the side away from the interior of the shell 11, that is, the surface of the first pole 12 on the side away from the interior of the shell 11 is the pole outer end face 125. The notch 1241 of the receiving groove 124 passes through the pole outer end face 125. A plurality of through-holes 121 are all opened on the end wall 122 to connect the receiving groove 124 with the interior of the shell 11. The outer end 224 of the conductive portion 22 extends into the receiving groove 124 through the through-hole 121 and is connected to the end wall 122.

[0127] For example, when the first terminal 12 is disposed on the top wall of the housing 11, the terminal outer end surface 125 is the upper surface of the first terminal 12, and the accommodating groove 124 is formed as a groove with a notch 1241 open upward and the groove wall concave downward (i.e., concave toward the square near the battery cell assembly 2). For another example, when the first terminal 12 is disposed on the bottom wall of the housing 11, the terminal outer end surface 125 is the lower surface of the first terminal 12, and the accommodating groove 124 is formed as a groove with a notch 1241 open downward and the groove wall concave upward (i.e., concave toward the square near the battery cell assembly 2).

[0128] In the above technical solution, since the accommodating groove 124 is open toward the side of the first pole 12 away from the interior of the shell 11, it is beneficial to weld the conductive part 22 and the end wall 122 through the accommodating groove 124 from the outside of the first pole 12, that is, the side of the first pole 12 away from the active material coating part 21, and also facilitate external welding of the first pole 12 and the conductive part 22 through the accommodating groove 124, which facilitates the processing and manufacturing of the battery cell 10 and can save processing and manufacturing costs.

[0129] Exemplarily, the accommodating groove 124 can be constructed into a shape in which the length of the cross section is greater than the width, such as a rectangle, an ellipse, a runway shape, etc. The weld mark formed by welding the conductive part 22 to the first pole 12 can be a long strip weld mark parallel to the length direction of the accommodating groove 124 to improve welding reliability and increase overcurrent performance.

[0130] Referring again to FIG. 8 , in some optional embodiments of the present application, the outer ends 224 of the plurality of conductive portions 22 connected to the end wall 122 are stacked and connected on the end wall 122. That is, the plurality of conductive portions 22 on the end wall 122 are stacked and connected together to form an electrical connection with the first pole 12. In this way, by stacking the outer ends 224 of the plurality of conductive portions 22 on the end wall 122, the space occupied by the end wall 122 can be reduced, thereby facilitating a miniaturized design of the first pole 12.

[0131] Referring again to FIG. 16 , in some other optional embodiments of the present application, the outer ends 224 of the plurality of conductive portions 22 connected to the end wall 122 are spaced apart on the end wall 122. That is, the plurality of conductive portions 22 on the end wall 122 are non-stacked and are individually connected to the end wall 122 to form an electrical connection with the first pole 12. In this way, since each conductive portion 22 is individually connected to the end wall 122, the reliability of the electrical connection between each conductive portion 22 and the first pole 12 is improved.

[0132] Referring again to FIG8 , the housing assembly 1 further includes a pole cover 13, which cooperates with the first pole 12 and covers the notch 1241. The pole cover 13 is electrically connected to the first pole 12. In the above technical solution, by providing the pole cover 13 to close the notch 1241 of the receiving groove 124, leakage of electrolyte in the housing 11 from the notch 1241 of the receiving groove 124 can be prevented. Moreover, since the pole cover 13 closes the notch 1241 of the receiving groove 124 and is electrically connected to the first pole 12, the pole cover 13 can be used to easily achieve indirect electrical connection between the first pole 12 and the busbar, and this helps to increase the connection area of ​​the electrical connection, thereby helping to reduce the resistance of the electrical connection.

[0133] It is worth noting that the manner and position of the coupling between the pole cover 13 and the first pole 12 are not limited, as long as the pole cover 13 can seal the notch 1241 of the receiving slot 124. For example, during processing, the conductive portion 22 can first be passed through the through-hole 121 and welded to the end wall 122 of the receiving slot 124. The pole cover 13 can then be welded to the first pole 12 to seal the notch 1241 of the receiving slot 124. It should also be noted that the specific structure of the pole cover 13 is not limited, and for example, it can be a one-piece structure or a composite structure.

[0134] Please refer to FIG. 3-FIG . 8 and FIG. 11-FIG . 15 again for a description of the battery cell 10 according to a specific embodiment of the present application.

[0135] The battery cell 10 includes a shell assembly 1 and a cell assembly 2. The shell assembly 1 includes a shell 11. The shell 11 is provided with a positive electrode column and a negative electrode column. The positive electrode column and the negative electrode column are both first electrodes 12. The cell assembly 2 is accommodated in the shell 11 and includes a plurality of electrode assemblies 20. Each electrode assembly 20 includes an active material coating portion 21 and a conductive portion 22. The conductive portion 22 includes a gathering portion 221 and a connecting portion 222. The gathering portion 221 is formed by gathering a plurality of pole tabs 220. The connecting portion 222 is formed by gathering a plurality of pole tabs 220. The gathered and connected parts are formed, the gathered part 221 connects the connecting part 222 and the active material coating part 21, the connecting part 222 is welded to the first pole 12 to be electrically connected to the first pole 12, the connection position of the gathered part 221 and the connecting part 222 is the connecting root 223, and the first pole 12 is provided with a through-hole 121 at the position of the connecting root 223 of each conductive part 22 of each electrode assembly 20, and the conductive part 22 is passed through the through-hole 121 corresponding to the connecting root 223, so that each through-hole 121 is respectively passed through by a conductive part 22.

[0136] Furthermore, the first pole 12 includes an end wall 122 and a side wall 123, the end wall 122 is located on the side of the side wall 123 close to the interior of the shell 11, the end wall 122 and the side wall 123 are arranged to form a receiving groove 124, and the notch 1241 of the receiving groove 124 is open to the side away from the interior of the shell 11, and multiple through-holes 121 are all opened on the end wall 122 to connect the receiving groove 124 with the interior of the shell 11, each through-hole 121 is a long strip hole, and the multiple through-holes 121 on the end wall 122 are arranged at intervals along the width direction of the through-hole 121. The conductive portion 22 includes a connecting portion 222 that passes through the through-hole 121. The length of the portion of the connecting portion 222 located within the through-hole 121 is aligned with the length of the through-hole 121, and the width of the through-hole 121 is arranged along the thickness of the connecting portion 222. The connecting portion 222 extends from the through-hole 121 into the receiving slot 124 and is welded to the end wall 122. Multiple connecting portions 222 welded to the end wall 122 are stacked and welded together on the end wall 122. The pole cover 13 is welded to the notch 1241, covering the notch 1241 and electrically connected to the first pole 12.

[0137] In the above technical solution, since each first pole 12 in the battery cell 10 is penetrated and connected with multiple conductive parts 22, and each conductive part 22 includes multiple pole tabs 220 that are stacked and folded together, the number of pole tabs 220 included in each conductive part 22 can be reduced, and the folded height of the multiple pole tabs 220 in each conductive part 22 can be reduced, so that the size occupied by each conductive part 22 in the direction of the pole tab extension in the shell 11 can be reduced. When the size of the shell 11 is constant, the space that can be occupied by the active material coating part 21 in the direction of the pole tab extension can be increased, which is beneficial to improve the energy density of the battery cell 10.

[0138] According to some embodiments of the present application, the present application further provides a battery 100, comprising the battery cell 10 of any of the above embodiments. In the above technical solution, since the battery 100 is provided with the above battery cell 10, the energy density of the battery cell 10 can be increased, thereby facilitating an increase in the energy density of the battery 100.

[0139] According to some embodiments of the present application, the present application further provides an electric device 1000, which includes the battery 100 of the above embodiment, and the battery 100 is used to provide electrical energy to the electric device 1000. In the above technical solution, since the electric device 1000 is provided with the above battery 100, the energy density of the battery 100 can be improved, which is conducive to improving the service life of the electric device 1000. It is understandable that when the electric device 1000 is a vehicle, the improved service life of the battery 100 is conducive to improving the vehicle's cruising range.

[0140] 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.

[0141] 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 battery cell, wherein: include: A housing assembly, comprising a housing and a first pole arranged on the housing; A battery cell assembly is housed in the housing and includes a conductive portion electrically connected to the first pole, wherein the conductive portion includes a plurality of tabs that are stacked and connected together; The first pole is electrically connected to a plurality of the conductive parts, and the first pole has a plurality of through holes, each of the through holes is respectively provided with at least one of the conductive parts.

2. The battery cell according to claim 1, wherein: The battery cell assembly includes at least one electrode assembly, each of the electrode assemblies includes the conductive portion, and the first pole is provided with the through holes at positions corresponding to each of the electrode assemblies.

3. The battery cell according to claim 2, wherein: The electrode assembly includes an active material coating portion, and the conductive portion includes a gathering portion and a connecting portion, wherein the gathering portion is formed by gathering a plurality of the pole tabs, and the connecting portion is formed by gathering and connecting a plurality of the pole tabs, and is used to be electrically connected to the first pole, and the gathering portion connects the connecting portion and the active material coating portion, and the connection position between the gathering portion and the connecting portion is a connecting root; the first pole is provided with the through hole at a position corresponding to at least one of the connecting roots in each of the electrode assemblies.

4. The battery cell according to claim 2 or 3, wherein: The first pole is provided with the through holes in the middle area in the thickness direction corresponding to each of the electrode assemblies.

5. The battery cell according to any one of claims 2 to 4, wherein: The electrode assembly includes an active material coating portion, and the conductive portion includes a gathering portion and a connecting portion, wherein the gathering portion is formed by gathering a plurality of the pole tabs, and the connecting portion is formed by gathering and connecting a plurality of the pole tabs, and is used to be electrically connected to the first pole, and the gathering portion connects the connecting portion and the active material coating portion, and the connection position between the gathering portion and the connecting portion is a connecting root; at least one of the connecting roots in the electrode assembly corresponds to the middle area in the thickness direction of the electrode assembly.

6. The battery cell according to any one of claims 2 to 5, wherein: The battery cell assembly includes at least one combination, each combination includes two electrode assemblies, each electrode assembly in each combination includes multiple conductive parts with the same polarity, and at least two conductive parts with the same polarity belonging to different electrode assemblies and arranged adjacently in each combination are connected.

7. The battery cell according to any one of claims 1 to 6, wherein: The battery cell assembly includes at least one electrode assembly, each of the electrode assembly includes at least one conductive part, the electrode assembly includes an active material coating part, the conductive part includes a gathering part and a connecting part, the gathering part is formed by gathering a plurality of the pole tabs, the connecting part is formed by gathering and connecting a plurality of the pole tabs, and is used to be electrically connected to the first pole, the gathering part connects the connecting part and the active material coating part, the connection position between the gathering part and the connecting part is a connecting root, and the conductive part is penetrated through a through hole that is closest to the corresponding connecting root.

8. The battery cell according to any one of claims 3, 5 and 7, wherein: The through holes are respectively arranged on the first pole at positions corresponding to the connection roots of each of the conductive parts.

9. The battery cell according to any one of claims 1 to 8, wherein: The through hole is a long strip hole, and the conductive part includes a connecting part penetrated through the through hole. The connecting part is sheet-shaped and the length direction of the part located in the through hole is consistent with the length direction of the through hole, and the width direction of the through hole is consistent with the thickness direction of the connecting part.

10. The battery cell according to claim 9, wherein: The spacing direction of the plurality of through holes on the first pole is different from the length direction of the through holes.

11. The battery cell according to any one of claims 1 to 10, wherein: The conductive part is composed of a plurality of the pole tabs, and the pole tabs are welded to the first pole; or, the conductive part further includes a transfer plate, and the pole tabs are connected to the first pole via the transfer plate.

12. The battery cell according to any one of claims 1 to 11, wherein: The first pole has a receiving groove communicated with the through hole, and a part of the conductive part passes through the through hole and is received in the receiving groove.

13. The battery cell according to claim 12, wherein: The first pole includes an end wall and a side wall, wherein the end wall is located on a side of the side wall close to the interior of the shell, and the end wall and the side wall are arranged to form the accommodating groove, the notch of the accommodating groove is open toward a side away from the interior of the shell, and a plurality of through holes are provided on the end wall to connect the accommodating groove with the interior of the shell, and the outer end of the conductive part extends into the accommodating groove through the through hole and is connected to the end wall.

14. The battery cell according to claim 13, wherein: The outer ends of the plurality of conductive parts connected to the end wall are stacked and connected on the end wall; or, the outer ends of the plurality of conductive parts connected to the end wall are spaced apart on the end wall.

15. The battery cell according to claim 13 or 14, wherein: The housing assembly further includes a pole cover plate, which cooperates with the first pole and covers the notch, and is electrically connected to the first pole.

16. The battery cell according to any one of claims 1 to 15, wherein: The shell is provided with a plurality of poles, at least one of which is the first pole.

17. A battery, wherein: The invention comprises a battery cell according to any one of claims 1 to 16.

18. An electrical device, wherein: Comprising a battery according to claim 17.

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