Battery monomer, battery device and power utilization device

Abstract

The embodiment of the utility model provides a battery monomer, a battery device and a power utilization device. The battery monomer comprises a shell assembly, an electrode assembly and a current collecting component, the shell assembly is provided with a containing cavity, the electrode assembly is located in the containing cavity and comprises a main body part and a tab, and the tab is arranged on one side, in the first direction, of the main body part. The current collecting component is arranged between the shell assembly and the tab in the first direction; the current collecting component comprises a first connecting part and a second connecting part; and along the first direction, the first connecting part is connected with the second connecting part, the first connecting part is connected with the tab, and the second connecting part is connected with the shell assembly. Wherein in the first direction, the current collecting component abuts against the tab, the shell assembly abuts against the second connecting part, the first connecting part and the shell assembly are arranged in a spaced mode, and the first connecting part is provided with a groove and / or a protrusion. According to the battery monomer provided by the embodiment of the invention, the stability of connection between the current collecting component and the shell assembly and the electrode assembly can be improved.

Description

Technical Field

[0001] This application relates to the field of battery technology, and in particular to a battery cell, battery device, and power supply device. Background Technology

[0002] With the development of new energy technologies, batteries are being used more and more widely, for example in mobile phones, laptops, electric vehicles, electric cars, electric airplanes, electric ships, electric toy cars, electric toy ships, electric toy airplanes, and power tools. Batteries are also widely used in the energy storage field.

[0003] With the widespread development and application of battery technology, how to improve the stability of the connection between various components during the assembly and use of battery cells, and improve the service life and safety performance of battery cells, is an urgent problem to be solved. Utility Model Content

[0004] This application provides a battery cell, a battery device, and an electrical device, which can effectively improve the stability of the connection between the current collector, electrode assembly, and casing assembly inside the battery cell.

[0005] In a first aspect, embodiments of this application provide a battery cell, including a housing assembly, an electrode assembly, and a current collector. The housing assembly includes a receiving cavity, and the electrode assembly is located within the receiving cavity of the housing assembly. The electrode assembly includes a main body and a tab, with the tab disposed on one side of the main body along a first direction. Along the first direction, the current collector is disposed between the tab and the housing assembly. The current collector includes a first connecting portion and a second connecting portion, which are connected. The first connecting portion is connected to the tab, and the second connecting portion is connected to the housing assembly. Along the first direction, the current collector abuts against the tab, and the housing assembly abuts against the second connecting portion; the first connecting portion and the housing assembly are spaced apart. The first connecting portion has a groove and / or a protrusion.

[0006] In the above embodiments, the first connecting part is provided with a groove, which can form a weak area in the first connecting part. When the first connecting part deforms, the weak area deforms first, absorbing the deformation of the first connecting part and reducing the impact of the deformation of the first connecting part on the second connecting part. The first connecting part is provided with a protrusion, which can form a local reinforcement area in the first connecting part, thereby reducing the deformation of the first connecting part and reducing the impact of the deformation of the first connecting part on the connection stability between the second connecting part and the shell, thus improving the stability of the connection between the current collector in the battery cell and the electrode assembly and the shell assembly.

[0007] In some embodiments, the housing assembly is provided with an exhaust component, which is disposed opposite to the first connection portion along a first direction.

[0008] In the above embodiments, the venting component can be either a vent valve or an explosion-proof valve. When the venting component is a vent valve, it can control the internal pressure of the battery cell, releasing the gas accumulation formed during charging and discharging, thereby helping to maintain the optimal operating state of the battery cell and extending its service life. Furthermore, battery cells may experience thermal runaway when overcharged, over-discharged, short-circuited, or due to internal faults. When the venting component is an explosion-proof valve, it can release pressure when the internal pressure of the battery cell rises to a certain level, preventing the battery cell from exploding.

[0009] In some embodiments, the first connecting portion is provided with one or more through holes, the through holes being disposed opposite to the exhaust component, and the grooves and / or protrusions being annular and surrounding the through holes.

[0010] In the above embodiments, the through hole is correspondingly arranged with the exhaust component, forming a channel between the electrode assembly and the exhaust component, which facilitates the discharge of gas generated during the charging and discharging process of the electrode assembly. Furthermore, the through hole on the first connecting portion serves a similar function to the groove, reducing the impact of deformation of the first connecting portion on the second connecting portion, thereby reducing the possibility of unstable gap connections between the second connecting portion and the housing assembly due to deformation of the first connecting portion.

[0011] In some embodiments, the first connecting portion is provided with one or more through holes, the through holes being correspondingly provided with the exhaust component, and the grooves and / or protrusions being located between adjacent through holes.

[0012] In the above embodiments, the grooves and / or protrusions are arranged between the through holes to adapt to different sizes and positions of the through holes, which not only meets the requirement of venting the gas in the battery cell from the exhaust component, but also meets the requirement of absorbing deformation or local reinforcement on the first connection part.

[0013] In some embodiments, the housing assembly includes a protrusion that protrudes in a first direction toward a side opposite to the electrode assembly, and an exhaust component is disposed on the protrusion.

[0014] In the above embodiment, the exhaust component is located on the protrusion, which can achieve the gap setting between the first connecting part and the outer shell assembly, providing a certain buffer space for the gas generated during battery charging and discharging. The exhaust component is located on the protrusion, which is conducive to the smooth discharge of gas.

[0015] In some embodiments, the first connecting part and the electrode base are made of the same material and are connected to the electrode, the second connecting part and the housing assembly base are made of the same material and are connected to the housing assembly, and the electrode and the housing assembly base are made of different materials.

[0016] In the above embodiments, the first connecting part can be directly welded to the electrode tab, and the second connecting part can be directly welded to the housing assembly. When welding the same metal, laser welding is less difficult and produces higher weld quality, which can improve the stability of the connection between the first connecting part and the electrode tab, and between the second connecting part and the housing assembly. The first connecting part and the second connecting part use dissimilar metal penetration welding to improve the welding strength and meet the overcurrent requirements.

[0017] In some embodiments, the second connecting portion is an annular structure, and along the radial direction of the current collecting member, the second connecting portion is located outside the first connecting portion.

[0018] In the above embodiment, the first connecting part and the second connecting part are arranged radially, which can save space in the first direction and improve energy density.

[0019] In some embodiments, the second connection portion is an annular structure and is disposed along the first direction on the side of the first connection portion away from the electrode assembly.

[0020] In the above embodiment, this structure sets the second connecting part as a ring structure to achieve a gap between the first connecting part and the outer casing assembly, reserving a certain buffer space for the gas generated during the charging and discharging of the battery cell, which is beneficial to control the gas pressure inside the battery cell.

[0021] In some embodiments, a protrusion is provided on the side of the first connecting portion facing the second connecting portion.

[0022] The above-described embodiment can prevent the protrusion from affecting the welding of the first connecting part and the electrode tab.

[0023] In some embodiments, the thickness of the second connecting portion is M, the height of the protrusion is H, and the relationship between M and H satisfies: M≥H.

[0024] In the above embodiment, the protrusion on the first connecting part will not extend beyond the upper surface where the second connecting part is located, and will not affect other components within the battery cell.

[0025] In some embodiments, the protrusion is disposed in a first direction on the side of the first connection portion opposite to the electrode assembly.

[0026] The above embodiment scheme offsets the raised plane from the plane that contacts the first connecting part and the electrode assembly, so as to avoid affecting the welding of the first connecting part and the electrode tab.

[0027] In some embodiments, the first connecting portion is provided with both a groove and a protrusion. Along the first direction, the groove is located on one side of the first connecting portion, and the protrusion is provided on the side of the first connecting portion away from the groove and is provided corresponding to the groove. The protrusion is provided on the side of the first connecting portion away from the electrode assembly.

[0028] The corresponding protrusions and grooves in the above embodiments can be stamped by the first connecting part along the first direction, which is convenient for processing and can simultaneously play the role of stress absorption and local reinforcement. At the same time, the protrusions are limited to the side of the first connecting part away from the electrode assembly, so as to avoid the protrusions affecting the welding of the first connecting part and the electrode tab.

[0029] In some embodiments, the grooves and / or protrusions are annular.

[0030] The annular grooves and protrusions in the above embodiments are simple and easy to form.

[0031] In some embodiments, the groove and / or protrusion are annular and coaxially arranged with the first connecting portion.

[0032] The grooves and protrusions in the above embodiments are more symmetrical, and the force on each part of the first connecting part is more uniform.

[0033] In some embodiments, the thickness of the first connecting portion is L, the groove depth is D, and the relationship between L and D satisfies: 0.4≤D / L≤0.8.

[0034] In the above embodiment, the groove depth is limited by using the thickness of the first connecting part as a reference. This allows the groove to achieve the desired effect of reducing the impact of the deformation of the first connecting part on the second connecting part, while also preventing the first connecting part from breaking due to the groove being too deep.

[0035] In some embodiments, the thickness of the first connecting portion is L, the height of the protrusion is H, and the relationship between L and H satisfies: 0.5≤H / L.

[0036] In the above embodiment, the height of the protrusion is limited by the thickness of the first connecting part, which can make the protrusion achieve the desired local reinforcement effect.

[0037] In some embodiments, the housing assembly includes electrode terminals and a housing, with the electrode terminals connected to a second connection portion along a first direction.

[0038] In the above embodiment, the electrode terminal is connected to the second connecting part, the first connecting part is connected to the tab, and the first connecting part is connected to the second connecting part. During the battery cell assembly process, the electrode terminal presses against the second connecting part along a first direction, and the first connecting part presses against the tab. Along the first direction, due to the gap between the first connecting part and the outer casing, the first connecting part is prone to deformation, which in turn causes the current collector to deform as a whole. Providing grooves and / or protrusions on the first connecting part can reduce the impact of the deformation of the first connecting part on the second connecting part, reduce the occurrence of unstable welding due to gaps between the second connecting part and the electrode terminal, and ultimately improve the stability of the connection between the current collector and the electrode assembly and the electrode terminal within the battery cell.

[0039] In some embodiments, the electrode terminal and the second connection portion are connected along a first direction. The first connection portion has an annular structure and is located outside the second connection portion along the radial direction of the current collecting member.

[0040] In the above embodiment, the first connecting part and the second connecting part are arranged radially, which can reduce the space occupied in the first direction and improve the energy density.

[0041] In some embodiments, the housing includes an end cap and a housing having an opening, the end cap covering the opening, and the end cap being connected to a second connection portion along a first direction.

[0042] In the above embodiment, the end cap is connected to the second connecting portion, the first connecting portion is connected to the electrode tab, and the first connecting portion and the second connecting portion are connected. During the battery cell assembly process, the end cap presses against the second connecting portion along a first direction, and the first connecting portion presses against the electrode tab. Due to the gap between the first connecting portion and the end cap, the first connecting portion is prone to deformation, which in turn causes the current collector component to deform as a whole. Providing grooves and / or protrusions on the first connecting portion can reduce the impact of the deformation of the first connecting portion on the second connecting portion, reduce the occurrence of unstable welding due to the gap between the second connecting portion and the end cap, and ultimately improve the stability of the connection between the current collector component, the electrode assembly, and the end cap within the battery cell.

[0043] Secondly, embodiments of this application provide a battery device, including a housing and a battery cell provided in any of the embodiments of the first aspect above, wherein the battery cell is housed within the housing.

[0044] Thirdly, embodiments of this application provide an electrical device including the battery provided in any of the embodiments of the second aspect described above. Attached Figure Description

[0045] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the embodiments of this application will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on the drawings without creative effort.

[0046] Figure 1 This is a schematic diagram of the structure of a vehicle disclosed in one embodiment of this application;

[0047] Figure 2 This is an exploded structural diagram of a battery pack disclosed in an embodiment of this application;

[0048] Figure 3 This is a cross-sectional view of a battery cell disclosed in an embodiment of this application;

[0049] Figure 4This is a partial detail view of a battery cell disclosed in an embodiment of this application;

[0050] Figure 5 This is a top view of a current collection component disclosed in an embodiment of this application;

[0051] Figure 6 This is a top view of a current collection component disclosed in an embodiment of this application;

[0052] Figure 7 This is a top view of a current collection component disclosed in an embodiment of this application;

[0053] Figure 8 This is a cross-sectional view of a current collection component disclosed in an embodiment of this application;

[0054] Figure 9 This is a cross-sectional view of a current collection component disclosed in an embodiment of this application;

[0055] Figure 10 This is a cross-sectional view of a current collection component disclosed in an embodiment of this application;

[0056] Figure 11 This is a cross-sectional view of a current collection component disclosed in an embodiment of this application;

[0057] Figure 12 This is a cross-sectional view of a battery cell disclosed in an embodiment of this application;

[0058] Figure 13 This is a partial detail view of a battery cell disclosed in an embodiment of this application;

[0059] The accompanying drawings are not drawn to scale.

[0060] Marker explanation:

[0061] 1000, Vehicle; 100, Battery unit; 200, Controller; 300, Motor;

[0062] 10. Housing; 11. First part; 12. Second part; 20. Battery cell;

[0063] 21. Housing; 22. Electrode assembly; 23. End cap; 24. Current collector; 25. Electrode terminal; 26. Housing assembly; 27. Exhaust component; 28. Protrusion; 221. Tab;

[0064] 241. First connecting part; 242. Second connecting part; 243. Protrusion; 244. Groove; 245. Through hole;

[0065] First direction, X. Detailed Implementation

[0066] The embodiments of this application will be described in further detail below with reference to the accompanying drawings and examples. The detailed description of the following embodiments and the accompanying drawings are used to illustrate the principles of this application by way of example, but should not be used to limit the scope of this application, that is, this application is not limited to the described embodiments.

[0067] In the description of this application, it should be noted that, unless otherwise stated, "a plurality of" means two or more; the terms "upper," "lower," "left," "right," "inner," and "outer," etc., indicating orientation or positional relationships, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this application. Furthermore, the terms "first," "second," and "third," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance. "Vertical" is not vertical in the strict sense, but within the allowable tolerance range. "Parallel" is not parallel in the strict sense, but within the allowable tolerance range.

[0068] The directional terms used in the following description refer to the directions shown in the figures and are not intended to limit the specific structure of this application. It should also be noted in the description of this application that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0069] In this application, the battery cell can be a secondary battery, which refers to a battery cell that can be recharged to activate the active materials and continue to be used after the battery cell has been discharged.

[0070] The battery cell can be a lithium-ion battery, sodium-ion battery, sodium-lithium-ion battery, lithium metal battery, sodium metal battery, lithium-sulfur battery, magnesium-ion battery, nickel-metal hydride battery, nickel-cadmium battery, lead-acid battery, etc., and the embodiments of this application are not limited to this.

[0071] A single battery cell typically includes an electrode assembly. The electrode assembly includes a positive electrode, a negative electrode, and a separator, with the separator positioned between the positive and negative electrodes. During the charging and discharging process of a single battery cell, active ions (such as lithium ions) repeatedly insert and extract between the positive and negative electrodes. The separator, positioned between the positive and negative electrodes, prevents short circuits while allowing active ions to pass through.

[0072] In some embodiments, the positive electrode may be a positive electrode sheet, which may include a positive electrode current collector and a positive electrode active material disposed on at least one surface of the positive electrode current collector. The positive electrode current collector has two surfaces opposite each other in its own thickness direction, and the positive electrode active material is disposed on either or both of the opposite surfaces of the positive electrode current collector. As an example, the positive electrode current collector may be a metal foil, a conductive polymer material, a carbon material, or a composite current collector.

[0073] In some embodiments, the negative electrode may be a negative electrode sheet, which may include a negative electrode current collector. As an example, the negative electrode sheet may include a negative electrode current collector and a negative electrode active material disposed on at least one surface of the negative electrode current collector. The negative electrode current collector has two surfaces opposite each other in its own thickness direction, and the negative electrode active material is disposed on either or both of the opposite surfaces of the negative electrode current collector.

[0074] In some embodiments, the positive current collector may be made of aluminum, and the negative current collector may be made of copper. In some embodiments, the electrode assembly further includes a separator disposed between the positive and negative electrodes.

[0075] In some embodiments, the separator is a separator membrane. This application does not impose any particular limitation on the type of separator membrane; any known porous separator membrane with good chemical and mechanical stability can be selected.

[0076] As an example, the main material of the separator can be selected from at least one of glass fiber, non-woven fabric, polyethylene, polypropylene, polyvinylidene fluoride, and ceramic. The separator can be a single-layer film or a multi-layer composite film, without particular limitation. When the separator is a multi-layer composite film, the materials of each layer can be the same or different, without particular limitation. The separator can be a single component located between the positive and negative electrodes, or it can be attached to the surfaces of the positive and negative electrodes. An inorganic particle coating, an organic particle coating, or an organic / inorganic composite coating can also be applied to the surface of the separator.

[0077] In some embodiments, the separator is a solid electrolyte. The solid electrolyte is disposed between the positive and negative electrodes, serving both to transport ions and to isolate the positive and negative electrodes.

[0078] In some embodiments, a battery cell may include a housing assembly, which may include electrode terminals and a housing. The housing may be a steel housing, an aluminum housing, a plastic housing (such as a polypropylene housing), a composite metal housing (such as a copper-aluminum composite housing), or an aluminum-plastic film, etc. In some embodiments, the housing may be a sealed structure or a non-sealed structure. As an example, when the housing is a non-sealed structure, the housing serves to protect the electrode assembly, and a sealing bag is included between the housing and the electrode assembly to encapsulate the electrode assembly and electrolyte. Specifically, the sealing bag may be a bag-shaped insulating component or an aluminum-plastic film. When the housing is a sealed structure, it is used to encapsulate components such as the electrode assembly and electrolyte.

[0079] As an example, the battery cell can be a cylindrical battery cell, a prismatic battery cell, a pouch battery cell, or a battery cell of other shapes. Prismatic battery cells include prismatic battery cells, blade-shaped battery cells, and multi-prismatic batteries, such as hexagonal prismatic batteries. This application does not have any particular limitations.

[0080] In some embodiments, the housing includes an end cap and a housing, the housing having an opening, and the end cap covering the opening. The housing may have one or more openings. The end cap may also have one or more.

[0081] In a single battery cell, the electrode assembly and the casing assembly are electrically connected via a current collector to output the battery cell's electrical energy through the casing assembly. Specifically, the current collector is connected to the electrode assembly, and the casing assembly is connected to the current collector.

[0082] To facilitate the connection between the housing assembly and the current collector, the housing assembly can apply a compressive force to the current collector before connecting them. The inventors discovered that during battery cell assembly, the housing assembly exerts a significant compressive force on the current collector, causing substantial deformation. The current collector includes a first connecting part and a second connecting part. The first connecting part connects to the second connecting part and to the electrode tab, while the second connecting part connects to the housing assembly. When the current collector deforms under compressive force, a gap appears between the second connecting part and the housing assembly, resulting in unstable connection between the housing assembly and the electrode assembly, potentially leading to electrical connection failure.

[0083] During the assembly of a single battery cell, an interference fit is used in the direction perpendicular to the current collector to connect the casing and the current collector. Specifically, the end cap presses against the current collector, which in turn presses against the electrode tab. In terms of connection method, the first connecting part of the current collector connects to the electrode tab, the first connecting part connects to the second connecting part, and the second connecting part connects to the casing assembly. To facilitate the smooth discharge of gas from the electrode assembly, the casing assembly is equipped with a venting component, and a gap is created between the casing assembly and the first connecting part. This means that the first connecting part has no support on the side away from the electrode assembly, resulting in a state of stress imbalance, which can cause the first connecting part to bend and deform. Since the current collector, composed of the first and second connecting parts, is a single unit, the deformation of the first connecting part can cause the entire unit to bend. This creates a gap between the second connecting part and the casing assembly, preventing a complete fit and leading to unstable welding. Ultimately, this results in an unstable electrical connection between the electrode assembly and the casing assembly.

[0084] Therefore, this application provides a groove and / or a protrusion on the first connecting portion. The groove is a weak area; when the first connecting portion deforms, the groove will deform first, thus absorbing the deformation and reducing the impact of bending deformation of the first connecting portion on the second connecting portion. The protrusion can provide localized reinforcement, thereby reducing the stress on the second connecting portion. Both the groove and the protrusion can reduce the impact of deformation of the first connecting portion on the second connecting portion, thereby reducing the possibility of gaps between the second connecting portion and the housing assembly, ultimately enhancing the stability of the connection between the housing assembly and the current collector.

[0085] The technical solutions described in the embodiments of this application are applicable to battery devices and electrical devices using battery devices.

[0086] Electrical devices can include vehicles, mobile phones, portable devices, laptops, ships, spacecraft, electric toys, and power tools, etc. Vehicles can be gasoline-powered cars, natural gas-powered cars, or new energy vehicles; new energy vehicles can be pure electric vehicles, hybrid electric vehicles, or range-extended electric vehicles, etc. Spacecraft include airplanes, rockets, space shuttles, and spacecraft, etc. Electric toys include stationary or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, etc. Power tools include metal cutting power tools, grinding power tools, assembly power tools, and railway power tools, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete vibrators, and electric planers, etc. This application does not impose any special limitations on the above-mentioned electrical devices.

[0087] For ease of explanation, the following embodiments will use a vehicle as an example of an electrical device.

[0088] Please refer to Figure 1 , Figure 1This is a schematic diagram of the structure of a vehicle 1000 provided in some embodiments of this application. A battery device 100 is disposed inside the vehicle 1000, and the battery device 100 may be located at the bottom, front, or rear of the vehicle 1000. The battery device 100 can be used to power the vehicle 1000; for example, the battery device 100 can serve as the operating power source for the vehicle 1000.

[0089] The vehicle 1000 may also include a controller 200 and a motor 300. The controller 200 is used to control the battery device 100 to supply power to the motor 300, for example, for the power needs of the vehicle 1000 during startup, navigation and driving.

[0090] In some embodiments of this application, the battery device 100 can not only serve as the operating power source for the vehicle 1000, but also as the driving power source for the vehicle 1000, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000.

[0091] Please refer to Figure 2 , Figure 2 This is an exploded view of a battery device 100 provided in some embodiments of this application. The battery device 100 includes a housing 10 and battery cells 20, the housing 10 being used to house the battery cells 20.

[0092] The housing 10 is a component that houses the battery cell 20, providing a space for the battery cell 20. The housing 10 can adopt various structures. In some embodiments, the housing 10 may include a first part 11 and a second part 12, which overlap each other to define a space for accommodating the battery cell 20. The first part 11 and the second part 12 can have various shapes, such as a cuboid or a cylinder. The first part 11 can be a hollow structure open on one side, and the second part 12 can also be a hollow structure open on one side, with the open side of the second part 12 overlapping the open side of the first part 11, thus forming a housing 10 with a accommodating space. Alternatively, the first part 11 can be a hollow structure open on one side, and the second part 12 can be a plate-like structure, with the second part 12 overlapping the open side of the first part 11, thus forming a housing 10 with a accommodating space. The first part 11 and the second part 12 can be sealed using a sealing element, such as a sealing ring or sealant.

[0093] In the battery device 100, there can be one or more battery cells 20. If there are multiple battery cells 20, they can be connected in series, in parallel, or in a mixed configuration. A mixed configuration means that the multiple battery cells 20 are connected in both series and parallel. Alternatively, multiple battery cells 20 can be first connected in series, in parallel, or in a mixed configuration to form a battery module, and then multiple battery modules can be connected in series, in parallel, or in a mixed configuration to form a whole, which is then housed within the housing 10. Another option is that all the battery cells 20 can be directly connected in series, in parallel, or in a mixed configuration, and then the whole consisting of all the battery cells 20 is housed within the housing 10.

[0094] In some embodiments, the battery device 100 may further include a busbar component, through which multiple battery cells 20 can be electrically connected to each other to achieve series, parallel, or mixed connection of the multiple battery cells 20. The busbar component may be a metallic conductor, such as copper, iron, aluminum, stainless steel, aluminum alloy, etc.

[0095] In some embodiments, please refer to Figure 3 and Figure 4 This application provides a battery cell 20, which includes a housing assembly 26, an electrode assembly 22, and a current collector 24. The housing assembly 26 includes a receiving cavity, and the electrode assembly 22 is located within the receiving cavity of the housing assembly 26. The electrode assembly 22 includes a main body and a tab 221, which is disposed on one side of the main body along a first direction X. Along the first direction X, the current collector 24 is disposed between the tab 221 and the housing assembly 26. The current collector 24 includes a first connecting portion 241 and a second connecting portion 242, which are connected. The first connecting portion 241 is connected to the tab 221, and the second connecting portion 242 is connected to the housing assembly 26. Along the first direction X, the current collector 24 abuts against the tab 221, and the housing assembly 26 abuts against the second connecting portion 242. The first connecting portion 241 and the housing assembly 26 are spaced apart. The first connecting portion 241 is provided with a groove 244 and / or a protrusion 243.

[0096] The housing assembly 26 is a component used to house the electrode assembly 22. The housing assembly 26 can be a hollow structure with an opening at one end, or it can be a hollow structure with openings at both opposite ends. The housing assembly 26 can be in various shapes, such as a cylinder or a cuboid. The housing assembly 26 can be made of various materials, such as copper, iron, aluminum, steel, or aluminum alloy.

[0097] Electrode assembly 22 is the component in the battery cell 20 where the electrochemical reaction takes place. Electrode assembly 22 may include a positive electrode, a negative electrode, and a separator. Electrode assembly 22 can be a wound structure formed by winding the positive electrode, separator, and negative electrode, or a stacked structure formed by arranging the positive electrode, separator, and negative electrode in layers.

[0098] The electrode assembly 22 has tabs 221, which are divided into positive tabs and negative tabs. The positive tab can be the part of the positive electrode sheet that is not coated with a positive active material layer, and the negative tab can be the part of the negative electrode sheet that is not coated with a negative active material layer.

[0099] The first direction X refers to the thickness direction of the flow collector 24.

[0100] The current collector 24 is a component that enables electrical connection between two parts. For example, the current collector 24 enables electrical connection between the electrode assembly 22 and the housing assembly 26. The tabs 221 (positive or negative) of the electrode assembly 22 and the housing assembly 26 are both connected to the current collector 24 to achieve electrical connection between the housing assembly 26 and the electrode assembly 22. The current collector 24 can be of various shapes, such as circular or rectangular. The shape of the current collector 24 can be adapted to the shape of the housing 21. For example, if the housing 21 is cylindrical and the current collector 24 has a circular structure, the current collector 24 can also be called a current collector. The current collector 24 is connected to both the electrode assembly 22 and the housing assembly 26. The current collector 24 is connected to the tabs 221 of the electrode assembly 22 and to the housing assembly 26. The connection between the current collector 24 and the tab 221 of the electrode assembly 22 can be such that they are only in contact and not fixed together, for example, the current collector 24 and the tab 221 of the electrode assembly 22 abut against each other; or the connection can be such that they are fixed together, for example, the current collector 24 and the tab 221 of the electrode assembly 22 are welded together. Similarly, the connection between the housing assembly 26 and the current collector 24 can be such that they are only in contact and not fixed together, for example, the housing assembly 26 and the current collector 24 abut against each other; or the connection can be such that the housing assembly 26 and the current collector 24 are welded together. It should be noted that the tab 221 in the electrode assembly 22 connected to the current collector 24 can be either a positive or negative tab.

[0101] The first connecting part 241 is a component that connects the current collector 24 to the electrode 221. The connection between the first connecting part 241 and the electrode 221 can be either fixed to each other for electrical connection, such as by welding. Alternatively, the connection can be that the first connecting part 241 and the electrode 221 are only in contact for electrical connection, without being fixed, such as by abutting against each other. The first connecting part 241 can be connected entirely to the electrode 221, or it can be partially connected to the electrode 221. The base material of the first connecting part 241 can be the same as the base material of the electrode 221. The shape of the first connecting part 241 can be varied, including circular, rectangular, etc. The shape of the first connecting part 241 can be adapted to the shape of the housing assembly 26. When the housing assembly 26 is cylindrical, the first connecting part 241 can be circular, and when the housing assembly 26 is cuboid, the first connecting part 241 can be rectangular. The first connecting portion 241 can be a complete sheet structure. Considering the need for gas discharge within the electrode assembly 23, the first connecting portion 241 can also be a structure containing at least one through hole.

[0102] The second connecting part 242 is a component that connects the current collecting member 24 and the housing assembly 26. The connection between the second connecting part 242 and the housing assembly 26 can be either fixed to each other, such as by welding the second connecting part 242 to the housing assembly 26; or the connection can be that the two parts are only in contact and not fixed, such as by abutting against each other. The base material of the second connecting part 242 can be the same as the base material of the housing assembly 26. The shape of the second connecting part 242 can be varied, including circular, rectangular, etc. The shape of the second connecting part 242 can be adapted to the shape of the housing assembly 26; when the housing assembly 26 is cylindrical, the second connecting part 242 can be circular, and when the housing assembly 26 is cuboid, the second connecting part 242 can be rectangular.

[0103] The second connecting portion 242 can be on the same plane as the first connecting portion 241. In this case, the current collector 24 has a single-layer structure, and the first connecting portion 241 is located on the outer ring of the second connecting portion 242 along the radial direction of the current collector 24. Alternatively, the second connecting portion 242 can be on a different plane from the first connecting portion 241, with the second connecting portion 242 located on the side of the first connecting portion 241 away from the electrode assembly. In this case, the first connecting portion 241 and the second connecting portion 242 together form a double-layer structure of the current collector 24. The shape of the second connecting portion 242 can be the same as the shape of the first connecting portion 241, or it can be annular. The connection method between the first connecting portion 241 and the second connecting portion 242 can be welding or adhesive bonding.

[0104] The second connecting portion 242 is connected to the housing assembly 26, as in some embodiments, such as Figure 3 As shown, the housing assembly 26 includes electrode terminals 25, which are connected to the second connection portion 242 along the first direction X. In some embodiments, such as Figure 4 As shown, the housing assembly 26 includes an end cap 23, which is connected to the second connecting portion 242 along the first direction X.

[0105] The groove 244 can be a recessed space formed in the first connecting portion 241, and the thickness of the groove 244 can be less than the thickness of the first connecting portion 241. The protrusion 243 is a structure that protrudes from the surface of the first connecting portion 241, and the thickness of the protrusion 243 can be greater than the thickness of the first connecting portion 241.

[0106] The placement of the groove 244 and / or protrusion 243 needs to be adapted to the specific structure of the first connecting portion 241. For example, when the first connecting portion 241 is a complete sheet structure, the groove 244 and / or protrusion 243 can be continuously disposed on the surface of the first connecting portion 241. When the first connecting portion 241 has a structure with at least one through hole, the groove 244 and / or protrusion 243 can be intermittently disposed between the through holes; when the through holes are concentrated in the middle area of ​​the first connecting portion 244, the groove 244 and / or protrusion 243 can also be continuously disposed on the surface of the first connecting portion 241, surrounding the through holes. Considering the connection strength between the first connecting portion 241 and the tab 221, the positions of the protrusion 244 and groove 243 can be staggered from the connection solder joint positions between the first connecting portion 241 and the tab 221. The groove 244 and / or the protrusion 243 may be located on the side of the first connecting portion 241 away from the electrode assembly 22 along the first direction X, or on the side of the first connecting portion 241 facing the electrode assembly 22 along the first direction X.

[0107] The shape of the groove 244 and / or the protrusion 243 can be adapted to the shape of the first connecting portion 241. For example, when the first connecting portion 241 is circular, the groove 244 and / or the protrusion 243 is annular. The shape of the groove 244 and / or the protrusion 243 may also not be adapted to the shape of the first connecting portion 241. For example, when the first connecting portion 241 is circular, the groove 244 and / or the protrusion 243 can be rectangular or other shapes.

[0108] When the first connecting portion 241 is provided with both a groove 244 and a protrusion 243, the groove 244 and the protrusion 243 can be located on the same side of the first connecting portion 241, either on the side away from the electrode assembly along the first direction X or on the side facing the electrode assembly 22 along the first direction X. Alternatively, the groove 244 and the protrusion 243 can be located on the side of the first connecting portion 241 away from the electrode assembly 22 along the first direction X and on the side facing the electrode assembly 22, respectively. For example, the groove 244 is located on the side of the first connecting portion 241 away from the electrode assembly 22 along the first direction X, and the protrusion 243 is located on the side of the first connecting portion 241 facing the electrode assembly 22 along the first direction X. When the groove 244 and the protrusion 243 are located on opposite sides of the first connecting portion 241, the groove 244 and the protrusion 243 can be provided correspondingly or not correspondingly.

[0109] In this embodiment, the first connecting portion 241 is provided with a groove 244, which can form a weak area in the first connecting portion 241. When the first connecting portion 241 deforms, the weak area deforms first, absorbing the deformation of the first connecting portion 241 and reducing the impact of the deformation of the first connecting portion 241 on the second connecting portion 242. The first connecting portion 241 is provided with a protrusion 243, which can form a local reinforcement area in the first connecting portion 241, thereby reducing the amount of deformation of the first connecting portion 241, and further reducing the impact of the deformation of the first connecting portion 241 on the connection stability between the second connecting portion and the housing 21. The provision of both the protrusion 243 and the groove 244 can reduce the impact of the deformation of the first connecting portion 241 on the second connecting portion 242, reduce the gap between the second connecting portion 242 and the housing assembly 26, and ultimately improve the stability of the connection between the current collector 24 in the battery cell 20, the electrode assembly 22, and the housing assembly 26.

[0110] In some embodiments, please continue to refer to Figure 4 The housing assembly 26 is provided with an exhaust component 27, which is disposed opposite to the first connecting portion 241 along the first direction X.

[0111] The venting component 27 can be either a vent valve or an explosion-proof valve. When the venting component 27 is a vent valve, it can control the internal pressure of the battery cell 20, releasing the gas accumulation formed in the battery cell 20 during charging and discharging, thereby helping to maintain the optimal operating state of the battery cell 20 and extending its service life. When the venting component 27 is an explosion-proof valve, a weak structure can be provided on the venting component 27, which is actuated to release the internal pressure or temperature when the internal pressure or temperature of the battery cell 20 reaches a threshold. The venting component 27 can be integrally formed with the housing component 26. Alternatively, the venting component 27 can be separately installed and connected to the housing component 26.

[0112] When the internal pressure or temperature of the battery cell 20 reaches a predetermined threshold, the venting component 27 activates or a weak structure within the venting component 27 is damaged, thereby creating an opening or channel for the internal pressure or temperature to be released. This threshold design varies depending on design requirements and may depend on the materials of one or more of the positive electrode, negative electrode, electrolyte, and separator in the battery cell 20.

[0113] The term "actuation" as used in this application refers to the venting component 27 being activated or undergoing a certain state, thereby releasing the internal pressure and temperature of the battery cell 20. The action of the venting component 27 may include, but is not limited to: movement of components within the venting component 27 to form an venting channel, rupture, breakage, tearing, or opening of at least a portion of the venting component 27, etc. When the venting component 27 is actuated, the high-temperature, high-pressure substances inside the battery cell 20 are discharged outwards from the actuated portion as exhaust materials. This method enables pressure and temperature relief in the battery cell 20 under controllable pressure or temperature conditions, thereby preventing potentially more serious accidents.

[0114] In some embodiments, when the housing assembly 26 is a non-sealed structure, the venting component 27 can be configured as a through hole for venting gas inside the battery cell 20.

[0115] The emissions from the battery cell 20 mentioned in this application include, but are not limited to: electrolyte, dissolved or split positive and negative electrode plates, fragments of separators, high-temperature and high-pressure gases generated by the reaction, flames, etc.

[0116] In this embodiment, the housing assembly 26 is provided with an exhaust component 27, which is disposed opposite to the first connecting portion 241 along a first direction. The exhaust component 27 can be an exhaust valve or an explosion-proof valve. When the exhaust component 27 is an exhaust valve, it can control the internal pressure of the battery cell, releasing the gas accumulation formed during charging and discharging, thereby helping to maintain the optimal operating state of the battery cell and extending its service life. When the exhaust component 27 is an explosion-proof valve, its placement on the housing assembly 26 allows for pressure release when the battery cell 20 experiences thermal runaway due to overcharging, over-discharging, short circuit, or internal fault, preventing potentially more serious accidents.

[0117] In some embodiments, please refer to Figures 5-7 The first connecting part 241 is provided with one or more through holes 245, the through holes 245 are disposed opposite to the exhaust component 27, and the groove 244 and / or protrusion 243 are annular and are disposed around the through holes 245.

[0118] The through hole 245 is a structure that penetrates the first connecting part 241. There can be one or more through holes 245. The shape of the through hole 245 can be varied, such as elliptical, rectangular, circular, etc. Multiple through holes 245 can have the same shape or different shapes.

[0119] The through hole 245 is disposed opposite to the exhaust component 27, and the orthographic projection of the exhaust component 27 along the first direction X on the first connecting part 241 may overlap with the through hole 245.

[0120] In this embodiment, the through hole 245 is disposed opposite to the exhaust component 27, forming a channel between the electrode assembly 22 and the exhaust component 27, thereby facilitating the discharge of gas generated during the charging and discharging process of the electrode assembly 22. Furthermore, the through hole 245 disposed on the first connecting portion 241 can absorb stress, thereby reducing the impact of deformation of the first connecting portion 241 on the connection stability between the second connecting portion and the housing 21.

[0121] In some embodiments, please refer to Figure 7 The first connecting part 241 is provided with one or more through holes 245, the through holes 245 are correspondingly provided with the exhaust component 27, and the groove 244 and / or protrusion 243 are located between adjacent through holes 245.

[0122] The groove 244 and / or the protrusion 243 are located between adjacent through holes 245, and the groove 244 and / or the protrusion 243 can be an intermittent structure.

[0123] The groove 244 and / or protrusion 243 provided in this application embodiment can be adapted to different sizes and positions of the through hole 245, which not only meets the requirement of venting the gas in the battery cell 20 from the exhaust component 27, but also meets the requirement of absorbing stress or local reinforcement on the first connection part 241.

[0124] In some embodiments, please refer to Figure 4 The housing assembly 26 includes a protrusion 28, which protrudes in a first direction toward the side opposite to the electrode assembly 22, and an exhaust component 27 is disposed on the protrusion 28.

[0125] The protrusion 28 is a component provided on the housing assembly 26 that protrudes from the surface of the housing assembly 26. The protrusion 28 may protrude toward the side opposite to the electrode assembly 22. The protrusion 28 may be provided on the end cap 23 or on the housing 21. The shape of the protrusion 28 may be adapted to the shape of the surface of the housing 21. For example, if the surface of the housing 21 is circular, the protrusion 28 may also be circular. Alternatively, the shape of the protrusion 28 may not be adapted to the surface of the housing 21. For example, if the surface of the housing 21 is circular, the protrusion 28 may be rectangular.

[0126] In the structure provided in this embodiment, the gap between the first connecting part 241 and the outer casing assembly 26 is set by the protrusion 28, which provides a certain buffer space for the gas formed during the charging and discharging process of the battery cell 20, and the exhaust component 27 is provided in the protrusion 28 to facilitate the smooth discharge of gas.

[0127] In some embodiments, please refer to Figure 4 The first connecting part 241 and the tab 221 have the same base material and are connected to the tab 221. The second connecting part 242 and the outer shell assembly 26 have the same base material and are connected to the outer shell assembly 26. The tab 221 and the outer shell assembly 26 have different base materials.

[0128] The same base material can mean that the main elements and compounds constituting the material are consistent. For example, if it is a metallic material, the same base material may have the same main metallic components, and its impurity content is also within a similar range. For example, in some embodiments, the outer shell assembly 26 can be made of steel, and the connection end between the electrode assembly 23 and the current collector 24 is a negative electrode tab, which can be made of copper. Since the melting point of copper is about 1080°C and the melting point of steel is about 1400°C, when the two are directly laser welded, small cracks are easily generated. The assembly of the battery cell 20 has high requirements for airtightness, and the above-mentioned small cracks cannot meet the airtightness requirements. To solve this problem, a composite current collector 24 is used. The composite current collector includes a first connecting part 241 and a second connecting part 242. When the electrode tab 221 is made of copper, the corresponding material of the first connecting part 241 can be copper or a composite material such as copper-plated nickel. The base material of both is the same, which is copper. When the outer casing assembly 26 is made of steel, the corresponding second connecting part 242 can also be made of steel. The carbon content of the steel material of the outer casing assembly 26 and the steel material of the second connecting part 242 can be the same or different. The base material of both is the same, which is steel.

[0129] When welding metals with the same base material, laser welding is easier and produces higher quality welds, meeting both strength and airtightness requirements.

[0130] The current collector 24 provided in this embodiment is a composite structure. The base material of the first connecting part 241 is the same as the base material of the tab 221, and the first connecting part 241 can be directly welded to the tab 221. The base material of the second connecting part 242 is the same as the base material of the outer shell assembly 26, and the second connecting part 242 can be directly welded to the outer shell assembly 26. The current collector 24 composed of the first connecting part 241 and the second connecting part 242 can connect the tab 221 and the outer shell assembly 26. The second connecting part 242 can be directly welded to the outer shell assembly 26. When welding the same metal, laser welding is less difficult and produces higher welding quality, which can improve the stability of the connection between the first connecting part 241 and the tab 221, and between the second connecting part 242 and the outer shell assembly 26. The first connecting part 241 and the second connecting part 242 adopt dissimilar metal penetration welding to improve the welding strength and meet the current requirements.

[0131] In some embodiments, please refer to Figure 8 The second connecting part 242 is a ring structure, and along the radial direction of the current collecting member 24, the second connecting part 241 is located outside the first connecting part 242.

[0132] The second connecting portion 242 has a ring-shaped structure, which can be adapted to the shape of the battery cell 20. For example, when the battery cell 20 is cylindrical, the second connecting portion 242 can be a circular ring-shaped structure; when the battery cell 20 is a cuboid structure, the second connecting portion 242 can be a rectangular ring-shaped structure.

[0133] The current collector 24 provided in this application embodiment has a single-layer structure. The first connecting part 241 is located in the central region and is connected to the electrode tab 221. The second connecting part 242 is located on the outer ring of the first connecting part 241 and is connected to the outer shell assembly 26. The first connecting part 241 and the second connecting part 242 are arranged radially, which can save space in the first direction X and improve energy density.

[0134] In some embodiments, please refer to Figure 4 and Figures 9-11 The second connecting portion 242 has a ring-shaped structure and is disposed along the first direction on the side of the first connecting portion 241 away from the electrode assembly 22.

[0135] For example, the first connecting part 241 is circular and the second connecting part 242 is circular and annular. The first connecting part 241 and the second connecting part 242 are double-layered structures. The second connecting part 242 can be located between the first connecting part 241 and the outer shell assembly 26. The second connecting part 242 has a hollow structure in the middle. Through the hollow structure in the middle, there is a gap between the first connecting part 241 and the outer shell assembly 26.

[0136] The annular structure of the second connecting part 242 provided in this application embodiment realizes the gap setting between the first connecting part 241 and the outer shell assembly 26, providing a certain buffer space for the gas formed during the charging and discharging process of the battery, which is beneficial to control the gas pressure in the battery cell 20.

[0137] In some embodiments, please refer to Figure 4 The protrusion 243 is provided on the side of the first connecting part 241 facing the second connecting part 242.

[0138] The first connecting part 241 is connected to the tab 221 on the side facing the electrode assembly 22, while there is a gap between the side facing away from the electrode assembly 22 and the housing assembly 26.

[0139] The protrusion 243 provided in this embodiment, located on the side opposite to the electrode assembly 22, can avoid affecting the welding of the first connection portion 241 and the tab 221.

[0140] In some embodiments, please refer to Figure 11 The thickness of the second connecting part 242 is M, and the height of the protrusion 243 is H. The relationship between M and H is: M≥H.

[0141] The protrusion 243 serves to locally strengthen the first connecting part 241. The height of the protrusion 243 should be limited. If the protrusion 243 is too low, it cannot locally strengthen the first connecting part 241. If the protrusion 243 is too high, for example, when the protrusion 243 is higher than the first connecting part 241, the connection stability between the second connecting part 242 and the housing assembly 26 will be affected because the second connecting part 242 is connected to the housing assembly 26.

[0142] Under the size limitation provided in this embodiment, the protrusion 243 provided on the first connecting part 241 will not exceed the upper surface where the second connecting part 242 is located, and will not affect other components within the battery cell 20.

[0143] In some embodiments, please refer to Figure 8 and Figure 9 The first connecting portion 241 is provided with a groove 244 and a protrusion 243. Along the first direction, the groove 244 is located on one side of the first connecting portion 241 along the first direction, and the protrusion 243 is provided on the side of the first connecting portion 241 away from the groove 244 and is provided corresponding to the groove 244. The protrusion 243 is provided on the side of the first connecting portion 241 away from the electrode assembly 22.

[0144] For example, the first connecting portion 241 is circular, the second connecting portion 242 is annular, and the shapes of the groove 244 and the protrusion 243 can be adapted to the shape of the first connecting portion 241. For example, the first connecting portion 241 is circular, and the protrusion 243 and the groove 244 are annular. The protrusion 243 is located on the side of the first connecting portion 241 facing away from the electrode assembly 22, and the groove 244 is located on the side of the first connecting portion 241 facing the electrode assembly 22.

[0145] The first connecting portion 241 provided in this embodiment of the application, which is provided with groove 244 and protrusion 243 in cooperation, can be formed by stamping the first connecting portion 241 along the first direction, which is convenient for processing and can simultaneously absorb deformation and provide local reinforcement. At the same time, it restricts the protrusion 243 to be located on the side of the first connecting portion 241 away from the electrode assembly 22, so as to avoid the protrusion 243 affecting the welding of the first connecting portion 241 and the tab 221.

[0146] In some embodiments, please refer to Figure 5 and Figure 6 The groove 244 and / or the protrusion 243 are annular.

[0147] For example, the groove 244 is a ring structure, and the protrusion 243 is also a ring structure.

[0148] In this embodiment, the annular groove 244 and protrusion 243 have simple structures and are easy to form.

[0149] In some embodiments, please refer to Figure 6 and Figure 7 The groove 244 and / or the protrusion 243 are annular and coaxially arranged with the first connecting portion 241.

[0150] For example, the first connecting portion 241 is circular, the groove 244 can be a concentric circle adapted to the first connecting portion 241, and the protrusion 243 can also be a concentric circle adapted to the first connecting portion 241. Of course, when the first connecting portion 241 is rectangular, the groove 244 and the protrusion 243 can also be rectangles that coincide with the center of the first connecting portion 241.

[0151] The structure provided in this application embodiment has stronger symmetry, and the force on each part of the first connecting part 241 is more uniform.

[0152] In some embodiments, please refer to Figure 10 The thickness of the first connecting part 241 is L, and the depth of the groove 244 is D. The relationship between L and D satisfies: 0.4≤D / L≤0.8.

[0153] The groove 244 provided on the first connecting portion 241 is more easily deformed, thus absorbing the deformation of the first connecting portion 241. If the depth of the groove 244 is too small, it will not achieve the expected effect of reducing the impact of the deformation of the first connecting portion on the second connecting portion. If the depth of the groove 244 is too large, it may easily cause the first connecting portion 241 to break. Therefore, the depth of the groove 244 is limited with reference to the thickness of the first connecting portion 241. The depth of the groove 244 can be 0.4 times, 0.5 times, 0.6 times, 0.7 times, 0.8 times, etc., of the thickness of the first connecting portion 241.

[0154] In this embodiment, the depth of the groove 244 is limited by using the thickness of the first connecting portion 241 as a reference. This allows the groove 244 to achieve the desired effect of reducing the impact of the deformation of the first connecting portion on the second connecting portion, while avoiding the first connecting portion 241 from breaking due to the groove 244 being too deep.

[0155] In some embodiments, please refer to Figure 11 The thickness of the first connecting part 241 is L, and the height of the protrusion 243 is H. The relationship between L and H satisfies: 0.5≤H / L.

[0156] The protrusion 243 provided in the first connecting part 241 serves as a local reinforcement. When the height of the protrusion 243 is too small, it is difficult to achieve the expected effect, so its height needs to be limited. The height of the protrusion 243 can be 0.5 times, 0.6 times, 0.7 times, 0.8 times, or 0.9 times the thickness of the first connecting part 241, and the height of the protrusion 243 can be equal to the thickness of the first connecting part 241.

[0157] In this embodiment of the application, the height of the protrusion 243 is limited by the thickness of the first connecting portion 241, which can enable the protrusion 243 to achieve the desired local reinforcement effect.

[0158] In some embodiments, please refer to Figure 12 and Figure 13 The housing assembly 26 includes a housing and an electrode terminal 25, which is connected to the second connection portion 242 along the first direction X.

[0159] Electrode terminal 25 is electrically connected to electrode tab 221. Electrode terminal 25 can be directly connected to electrode tab 221, or indirectly connected to electrode tab 221 through current collector 24. Electrode terminal 25 can be disposed on end cap 23 or housing 21. Electrode terminal 25 can be riveted to housing 26 or welded to housing 26 by means of welding ring.

[0160] In this embodiment, electrode terminal 25 is connected to second connecting portion 242, first connecting portion 241 is connected to tab 221, and first connecting portion 241 is connected to second connecting portion 242. During the assembly of battery cell 20, electrode terminal 25 presses against second connecting portion 242 along the first direction X, and first connecting portion 241 presses against tab 221. Along the first direction X, due to the gap between first connecting portion 241 and housing 26, first connecting portion 241 is prone to deformation, which in turn causes overall deformation of current collector 24. Providing groove 244 and / or protrusion 243 on first connecting portion 241 can reduce the impact of deformation of first connecting portion 241 on second connecting portion 242, reduce the occurrence of unstable welding due to gap between second connecting portion 242 and electrode terminal 25, and ultimately improve the stability of the connection between current collector 24 and electrode assembly 22 and electrode terminal 25 within battery cell 20.

[0161] In some embodiments, the electrode terminal 25 and the second connection portion 242 are connected along a first direction. The first connection portion 241 has an annular structure and is located outside the second connection portion 242 along the radial direction of the current collector 24.

[0162] In this embodiment, the first connecting portion 241 and the second connecting portion 242 are arranged radially, which can reduce the space occupied in the first direction X and improve the energy density.

[0163] In some embodiments, please refer to Figure 3 and Figure 4 The outer casing includes a housing 21 and an end cap 23. The housing 21 has an opening, and the end cap 23 covers the opening. The end cap 23 is connected to the second connecting portion 242.

[0164] End cap 23 is a component that closes the opening of housing 21 to isolate the internal environment of battery cell 20 from the external environment. End cap 23 and housing 21 together define a sealed space for accommodating electrode assembly 22, electrolyte, and other components. The shape of end cap 23 can be adapted to the shape of housing 21; for example, if housing 21 is a cuboid structure, end cap 23 can be a rectangular structure adapted to housing 21; or, if housing 21 is a cylindrical structure, end cap 23 can be a circular structure adapted to housing 21. End cap 23 can also be made of various materials, such as copper, iron, aluminum, steel, or aluminum alloy. End cap 23 and housing 21 can be connected together by welding.

[0165] In this embodiment, the end cap 23 is connected to the second connecting portion 242, the first connecting portion 241 is connected to the electrode tab 221, and the first connecting portion 241 and the second connecting portion 242 are connected. During the assembly of the battery cell 20, the end cap 23 presses against the second connecting portion 242 along the first direction X, and the first connecting portion 241 presses against the electrode tab 221. Due to the gap between the first connecting portion 241 and the end cap 23, the first connecting portion 241 is prone to deformation, which in turn causes the current collector 24 to deform as a whole. Providing a groove 244 and / or a protrusion 243 on the first connecting portion 241 can reduce the impact of the deformation of the first connecting portion 241 on the second connecting portion 242, reduce the occurrence of unstable welding due to the gap between the second connecting portion 242 and the end cap 23, and ultimately improve the stability of the connection between the current collector 24 and the electrode assembly 22 and the end cap 23 within the battery cell 20.

[0166] This application provides a battery device 100, including a housing 10 and a battery cell 20 provided in any of the above embodiments, wherein the battery cell 20 is housed within the housing 10.

[0167] This application provides an electrical device, including the battery device 100 provided in any of the above embodiments.

[0168] In some embodiments, please refer to Figure 4 and Figure 8 This application provides a battery cell 20, including a housing 26, an electrode assembly 22, and a current collector 24. The housing 26 includes a receiving cavity, and the electrode assembly 22 is located within the receiving cavity. The electrode assembly 22 includes a main body and a tab 221, with the tab 221 disposed on one side of the main body along a first direction X. Along the first direction X, the current collector 24 is disposed between the tab 221 and the housing 21. The current collector 24 includes a first connecting portion 241 and a second connecting portion 242, which are connected. The first connecting portion 241 is connected to the tab 221, and the second connecting portion 242 is connected to the housing 21. Along the first direction X, the current collector 24 abuts against the tab 221, and the housing 26 abuts against the second connecting portion 242; the first connecting portion 241 and the housing 26 are spaced apart. The first connecting portion 241 is provided with a groove 244 and a protrusion 243. Along the first direction X, the groove 244 is located on one side of the first connecting portion 241 along the first direction X, and the protrusion 243 is disposed on the side of the first connecting portion 241 away from the groove 244 and is disposed corresponding to the groove 244. The protrusion 243 is disposed on the side of the first connecting portion 241 away from the electrode assembly 22.

[0169] The housing 26 includes a protrusion 28 that protrudes along a first direction X toward a side opposite to the electrode assembly 22. The protrusion 28 is provided with an exhaust component 27, which is disposed opposite to the first connecting portion 241 along the first direction X. The first connecting portion 241 has one or more through holes 245, which are disposed opposite to the exhaust component 27. A groove 244 and a protrusion 243 are annular and surround the through holes 245.

[0170] The first connecting part 241 and the tab 221 are made of the same base material and are connected to the tab 221. The second connecting part 242 and the outer shell 26 are made of the same base material and are connected to the outer shell 26. The base materials of the tab 221 and the outer shell 26 are different. The second connecting part 242 is an annular structure and is disposed along the first direction X on the side of the first connecting part 241 opposite to the electrode assembly 22. The thickness of the second connecting part 242 is M, and the height of the protrusion 243 is H. The relationship between M and H satisfies: 0.5≤H / M≤1. The thickness of the first connecting part 241 is L, and the depth of the groove 244 is D. The relationship between L and D satisfies: 0.4≤D / L≤0.8.

[0171] In this embodiment, the first connecting portion 241 is provided with a groove 244, which can form a weak area in the first connecting portion 241. When the first connecting portion 241 deforms, the weak area deforms first, absorbing the deformation of the first connecting portion 241 and reducing the impact of the deformation of the first connecting portion 241 on the second connecting portion 242. The first connecting portion 241 is provided with a protrusion 243, which can form a local reinforcement area in the first connecting portion 241, thereby reducing the amount of deformation of the first connecting portion 241, and further reducing the impact of the deformation of the first connecting portion 241 on the connection stability between the second connecting portion and the housing 21, thus improving the stability of the connection between the current collector 24 in the battery cell 20, the electrode assembly 22, and the housing 26.

[0172] Although this application has been described with reference to preferred embodiments, various modifications can be made thereto and components can be replaced with equivalents without departing from the scope of this application. In particular, the technical features mentioned in the various embodiments can be combined in any manner, provided there is no structural conflict. This application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A battery cell, characterized by, The application relates to a battery shell assembly. The battery shell assembly comprises: a shell assembly comprising a receiving cavity; an electrode assembly located in the receiving cavity, the electrode assembly comprising a main body and a tab, the tab being arranged on one side of the main body along a first direction; a current collecting member arranged between the shell assembly and the tab along the first direction, the current collecting member comprising a first connecting portion and a second connecting portion, the first connecting portion and the second connecting portion being connected, the first connecting portion being connected with the tab, and the second connecting portion being connected with the shell assembly; wherein, along the first direction, the current collecting member is in abutment with the tab, the shell assembly is in abutment with the second connecting portion, the first connecting portion is spaced apart from the shell assembly, and the first connecting portion is provided with a groove and / or a protrusion.

2. The battery cell of claim 1, wherein, The shell assembly is provided with an exhaust member, and the exhaust member is arranged opposite the first connecting portion along the first direction.

3. The battery cell of claim 2, wherein, The first connecting portion is provided with one or more through holes, the through holes are arranged opposite the exhaust member, the groove and / or the protrusion are annular, and the groove and / or the protrusion are arranged around the through holes.

4. The battery cell of claim 2, wherein, The first connecting portion is provided with a plurality of through holes, the through holes are arranged opposite the exhaust member, and the groove and / or the protrusion are located between adjacent through holes.

5. The battery cell of claim 2, wherein, The shell assembly comprises a protruding portion, the protruding portion is arranged protruding away from the electrode assembly along the first direction, and the exhaust member is arranged on the protruding portion.

6. The battery cell of any one of claims 1-5, wherein, The first connecting portion and the tab are made of the same base material and are connected with the tab, the second connecting portion and the shell assembly are made of the same base material and are connected with the shell assembly, and the base materials of the tab and the shell assembly are different.

7. The battery cell of claim 6, wherein, The second connecting portion is annular, and, along the radial direction of the current collecting member, the second connecting portion is located outside the first connecting portion.

8. The battery cell of claim 6, wherein, The second connecting portion is annular, and, along the first direction, the second connecting portion is arranged on the side of the first connecting portion away from the electrode assembly.

9. The battery cell of claim 8, wherein, The protrusion is arranged on the side of the first connecting portion facing the second connecting portion.

10. The battery cell of claim 9, wherein, The thickness of the second connecting portion is M, the height of the protrusion is H, and the relationship between M and H satisfies M>=H.

11. The battery cell of claim 1, wherein, The protrusion is arranged on the side of the first connecting portion away from the electrode assembly along the first direction.

12. The battery cell of claim 1, wherein, Along the first direction, the groove is located on one side of the first connecting portion along the first direction, the protrusion is arranged on the side of the first connecting portion away from the groove, and the protrusion is arranged opposite the groove.

13. The battery cell of claim 12, wherein, Along the first direction, the protrusion is arranged on the side of the first connecting portion away from the electrode assembly.

14. The battery cell of claim 1, wherein, The groove and / or the protrusion are annular.

15. The battery cell of claim 14, wherein, The groove and / or the protrusion are coaxially arranged on the first connecting portion.

16. The battery cell of claim 1, wherein, The thickness of the first connecting portion is L, the depth of the groove is D, and the relationship between L and D satisfies 0.4<=D / L<=0.

8.

17. The battery cell of claim 1, wherein, The thickness of the first connecting portion is L, the height of the protrusion is H, and the relationship between L and H satisfies 0.5<=H / L.

18. The battery cell of claim 1, wherein, The shell assembly comprises an electrode terminal and a shell, the electrode terminal is arranged on the shell, and, along the first direction, the electrode terminal is connected with the second connecting portion.

19. The battery cell of claim 18, wherein, The first connecting portion is annular in structure and is located outside the second connecting portion in a radial direction of the current collecting member.

20. The battery cell of claim 19, wherein, The housing includes an end cover and a casing having an opening, the end cover covering the opening and being connected to the second connecting portion in the first direction.

21. A battery device, characterized by A battery including the battery cell of any one of claims 1-20.

22. An electrical device, comprising: A battery device including the battery of claim 21.

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