Battery cells, battery packs and electrical devices

Abstract

This application relates to a battery cell, a battery assembly, and a power-consuming device. The battery cell includes a casing, a battery cell, and a top cover, with the casing having an opening. The battery cell is disposed within the casing, and a tab is provided at the end of the battery cell facing the opening. The top cover is disposed at the opening, and a receiving groove is provided on the side of the top cover facing the tab. The receiving groove is used to receive the tab, and the sidewall of the receiving groove gradually slopes towards the edge of the top cover from the bottom of the receiving groove towards the opening of the receiving groove. Each sidewall of the receiving groove is either flat or protrudes away from the tab. By setting the sidewall of the receiving groove to gradually slope towards the edge of the top cover from the bottom to the opening, the receiving space provided by the receiving groove is increased. Furthermore, setting each sidewall to be flat or protruding away from the tab further increases the bending space of the tab, which helps to solve the problem of the top cover compressing the tab, reduces the problems of insertion and breakage caused by the tab being compressed, thereby improving the safety and service life of the battery.

Description

Technical Field

[0001] This application relates to the field of battery technology, and in particular to battery cells, battery devices, and electrical devices. Background Technology

[0002] With the continuous development of battery technology, the application fields of batteries are becoming more and more extensive, and they are gradually developing towards higher capacity and higher safety.

[0003] The prismatic battery is a common type of battery, consisting of a casing, a cell, and a top cover. The cell is installed inside the casing, and the top cover is located at the opening of the casing. The top cover has electrode terminals, and the cell has tabs that are bent and connected to the tabs via adapter plates.

[0004] Traditional prismatic batteries suffer from insufficient space for the tabs, causing the tabs to be squeezed by the top cover, resulting in bending redundancy, tab insertion, or even breakage. This leads to problems such as poor overcurrent performance, insulation failure, and lithium plating capacity decay, seriously affecting the service life and safety of prismatic batteries. Utility Model Content

[0005] In view of the above problems, this application provides a battery cell, a battery device, and an electrical device, which solves the problems of insufficient bending space for the tabs and the top cover squeezing the tabs.

[0006] In a first aspect, this application provides a battery cell comprising:

[0007] The shell has an opening;

[0008] The battery cell is housed inside the casing; a tab is provided at the end of the battery cell facing the opening.

[0009] A top cover is provided at the opening; a receiving groove is provided on the side of the top cover facing the electrode tab, and the receiving groove is used to receive the electrode tab; the side wall of the receiving groove gradually slopes towards the edge of the top cover from the bottom of the receiving groove towards the opening of the receiving groove.

[0010] The sidewalls of each of the receiving grooves are either flat or protrude in a direction away from the electrode tab.

[0011] The battery cell provided in this application embodiment provides space for the tabs by setting a receiving groove on the top cover, thereby saving the height of the space between the cell and the top cover. By setting the sidewall of the receiving groove to gradually slope towards the edge of the top cover from the bottom of the groove towards the opening, the receiving space provided by the receiving groove is increased. By setting each sidewall of the receiving groove to be flat or protruding away from the tabs, the bending space provided by the receiving groove for the tabs is further increased, which helps to solve the problem of the top cover squeezing the tabs, reduces the problems of insertion and breakage caused by the tabs being squeezed, and thus improves the safety and service life of the battery.

[0012] In the technical solution of this application embodiment, on the cross section of the sidewall of the slot perpendicular to its extension direction, the connection point between the inner wall surface of the sidewall of the slot and the inner wall surface of the bottom of the slot is set as P, and the connection point between the inner wall surface of the sidewall of the slot and the surface of the top cover facing the cell is set as Q; the inner wall surface of the sidewall of the slot coincides with the line segment PQ or is located on the side of the line segment PQ away from the tab.

[0013] The battery cell provided in this application does not restrict the specific shape of the inner wall surface of the slot sidewall, as long as the inner wall surface of the slot sidewall coincides with the line segment PQ or is located on the side of the line segment PQ away from the electrode tab, so as to reduce the compression of the electrode tab.

[0014] In the technical solution of this application embodiment, on the cross-section of the groove sidewall perpendicular to its extension direction, the inner wall surface of the groove sidewall is straight or arc-shaped.

[0015] In the battery cell provided in this application embodiment, when the inner wall surface of the slot sidewall is straight, the inner wall surface of the slot sidewall coincides with the line segment PQ. When the inner wall surface of the slot sidewall is arc-shaped, the side of the inner wall surface line segment PQ away from the tab.

[0016] In the technical solution of this application embodiment, when the inner wall surface of the groove sidewall is arc-shaped, the inner wall surface of the groove sidewall protrudes to the side away from the electrode tab.

[0017] The battery cell provided in this application embodiment has a recessed structure formed on the inner wall surface of the slot sidewall, thereby providing a larger bending space for the tab.

[0018] In the technical solution of this application embodiment, the area of ​​the top cover without the receiving groove forms a top cover shoulder, and the top cover shoulder avoids the electrode tab.

[0019] The battery cell provided in this application embodiment has a top cover shoulder for connecting to the housing and for setting electrode terminals and other structures. By setting the top cover shoulder to avoid the electrode tabs, the electrode tabs are placed in the receiving groove, thus preventing the top cover shoulder from squeezing the electrode tabs.

[0020] In the technical solution of this application embodiment, the distance from the connection point Q to the adjacent top cover edge is set as L1; wherein, 1.5mm≤L1≤3.0mm.

[0021] The battery cell provided in this application embodiment, by limiting the range of L1 values, enables the top cover shoulder to be firmly connected to the housing, while also providing a large accommodating space in the receiving slot.

[0022] In the technical solution of this application embodiment, an electrode terminal is provided on the shoulder of the top cover, and the electrode terminal protrudes from the surface of the top cover shoulder away from the battery cell;

[0023] The bottom of the receiving groove protrudes towards the side of the top cover shoulder away from the battery cell, forming a convex hull structure.

[0024] The battery cell provided in this application embodiment has a convex hull structure, which makes the bottom of the receiving groove protrude outward from the outer surface of the top cover shoulder, occupying the height space of the electrode terminals protruding from the top cover shoulder, thereby reducing the space occupied inside the casing and thus improving the energy density of the battery cell.

[0025] In the technical solution of this application embodiment, the outer surface of the bottom of the tank is not higher than the electrode terminal.

[0026] The battery cell provided in this application embodiment can make full use of the height space occupied by the electrode terminals, without increasing the height of the battery cell along the Z direction.

[0027] In the technical solution of this application embodiment, the height difference between the convex bulge structure and the top cover shoulder is set as △H; wherein, 0mm<△H≤4.0mm.

[0028] The range of the value of ΔH for the battery cell provided in this application embodiment is specifically set according to parameters such as the distance between the electrode terminal and the top cover shoulder, and the required accommodation space for the electrode tab.

[0029] In the technical solution of this application embodiment, the minimum distance from the convex hull structure to the edge of the top cover shoulder is set to L2; wherein, 1.5mm≤L2≤3.0mm.

[0030] The battery cell provided in this application embodiment, by setting the value range of L2, maintains a safe distance between the welded area of ​​the top cover shoulder and the lower plastic, which helps to avoid burning the lower plastic during welding. At the same time, it maintains a large distance between the top cover shoulder and the convex structure, thereby enabling the receiving groove to have a larger capacity and thus improving the ability to accommodate the tabs.

[0031] In the technical solution of this application embodiment, the wall thickness T of the side wall of the receiving groove is not greater than the thickness of the bottom of the receiving groove.

[0032] The battery cell provided in this application embodiment is processed by stamping when processing the receiving groove. The side wall of the groove is stretched by the stamping and has a smaller wall thickness T compared with the bottom of the groove.

[0033] In the technical solution of this application embodiment, the wall thickness T of the groove sidewall is set to T≥1.2mm.

[0034] The battery cell provided in this application embodiment has a wall thickness T within this range, and the sidewall of the slot has high structural strength to reduce the deformation of the top cover.

[0035] In the technical solution of this application embodiment, a rounded corner is provided at the connection between the surface of the top cover shoulder facing the battery cell and the side wall of the slot; and / or

[0036] The connection between the sidewall and the bottom of the tank is rounded.

[0037] The battery cell provided in this application embodiment has rounded corners, which makes the bottom of the slot, the side wall of the slot, and the shoulder of the top cover smoothly connected, which helps to reduce damage to the tabs and provides good protection for the tabs.

[0038] Secondly, this application provides a battery device that includes the battery cell described in the above embodiments.

[0039] Thirdly, this application provides an electrical device that includes the battery device described in the above embodiments, the battery device being used to provide electrical energy.

[0040] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, the following are specific embodiments of this application. Attached Figure Description

[0041] Various other advantages and benefits will become apparent to those skilled in the art upon reading the detailed description of the preferred embodiments below. The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of this application. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:

[0042] Figure 1 This is a schematic diagram of the vehicle structure according to some embodiments of this application;

[0043] Figure 2 This is an exploded view of the battery device according to some embodiments of this application;

[0044] Figure 3 This is an exploded structural diagram of a battery cell according to some embodiments of this application;

[0045] Figure 4 This is a schematic cross-sectional view of a battery cell along the Y direction in some embodiments of this application;

[0046] Figure 5 for Figure 4 Enlarged structural diagram at point A in the middle;

[0047] Figure 6 This is a schematic cross-sectional view of the top cover along the Y direction of some embodiments of this application;

[0048] Figure 7 for Figure 6 Enlarged structural diagram at point B;

[0049] Figure 8This is a schematic diagram of the assembly structure of a battery cell according to some embodiments of this application;

[0050] Figure 9 This is a schematic diagram of the structure of the top cover and the bottom plastic after disassembly according to some embodiments of this application.

[0051] The reference numerals in the detailed embodiments are as follows:

[0052] 1000, Vehicle; 100, Battery unit; 200, Controller; 300, Motor;

[0053] 10. Box body; 11. First part; 12. Second part;

[0054] 20. Battery cell; 21. Top cover; 21a. Electrode terminal; 211. Receiving groove; 2111. Groove bottom; 2112. Groove sidewall; 212. Top cover shoulder; 213. Convex structure; 22. Housing; 23. Battery cell; 23a. Tab; 24. Lower plastic. Detailed Implementation

[0055] The embodiments of the technical solution of this application will now be described in detail with reference to the accompanying drawings. These embodiments are only used to more clearly illustrate the technical solution of this application and are therefore merely examples, and should not be used to limit the scope of protection of this application.

[0056] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms “comprising” and “having”, and any variations thereof, in the specification, claims, and foregoing description of the drawings are intended to cover non-exclusive inclusion.

[0057] In the description of the embodiments of this application, technical terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, "multiple" means two or more, unless otherwise explicitly defined.

[0058] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0059] In the description of the embodiments in this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this document generally indicates that the preceding and following related objects have an "or" relationship.

[0060] In the description of the embodiments of this application, the term "multiple" refers to two or more (including two), similarly, "multiple sets" refers to two or more (including two sets), and "multiple pieces" refers to two or more (including two pieces).

[0061] In the description of the embodiments of this application, the technical terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of this application and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application.

[0062] In the description of the embodiments of this application, unless otherwise expressly specified and limited, technical terms such as "installation," "connection," "joining," and "fixing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. For those skilled in the art, the specific meaning of the above terms in the embodiments of this application can be understood according to the specific circumstances.

[0063] Currently, judging from market trends, battery applications are becoming increasingly widespread. Batteries are not only used in energy storage systems such as hydropower, thermal power, wind power, and solar power plants, but also extensively used in electric vehicles such as electric bicycles, electric motorcycles, and electric cars, as well as in other fields. With the continuous expansion of battery applications, market demand is also constantly increasing.

[0064] The prismatic battery is a common type of battery, consisting of a casing, a cell, and a top cover. The cell is installed inside the casing, and the top cover is located at the opening of the casing. The top cover has electrode terminals, and the cell has tabs that are bent and connected to the tabs via adapter plates.

[0065] The inventors of this application have noticed that when the tabs are bent, they occupy a large space between the top cover and the cell, especially at the bend, where they are thicker than in other areas. To improve battery energy density, it is often necessary to reduce the space between the top cover and the cell. This makes the tabs easily compressed by the top cover, leading to bending redundancy, tab insertion, or even breakage. This, in turn, causes problems such as poor overcurrent performance, insulation failure, and lithium plating capacity decay, seriously affecting the lifespan and safety of the prismatic battery.

[0066] Based on the above considerations, in order to solve the problems of insufficient bending space for the tabs and the top cover compressing the tabs, the inventors, after in-depth research, designed a battery cell with a receiving groove on the side of the top cover facing the tabs to accommodate them. The sidewall of the receiving groove gradually slopes towards the edge of the top cover from the bottom to the opening, thereby increasing the receiving space. Furthermore, by bending the sidewall of the receiving groove away from the tabs, more bending space is provided for the tabs, thus solving the problem of the top cover compressing the tabs.

[0067] This application also provides an electrical device that provides electrical energy through the aforementioned battery device. The electrical device can be, but is not limited to, mobile phones, tablets, laptops, electric toys, power tools, electric vehicles, electric cars, ships, spacecraft, etc. Electric toys can include stationary or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, etc. Spacecraft can include airplanes, rockets, space shuttles, and spacecraft, etc.

[0068] In some embodiments, the electrical device can be a vehicle. The vehicle can be a gasoline-powered vehicle, a natural gas-powered vehicle, or a new energy vehicle; a new energy vehicle can be a pure electric vehicle, a hybrid electric vehicle, or a range-extended electric vehicle, etc. A battery device is installed inside the vehicle, and the battery device can be located at the bottom, front, or rear of the vehicle. The battery device can be used to power the vehicle; for example, the battery device can serve as the vehicle's operating power source. The vehicle may also include a controller and a motor, and the controller can be used to control the battery device to power the motor. For example, the battery device can be used to meet the vehicle's power needs during starting, navigation, and driving.

[0069] For ease of explanation, the following embodiments will be described using a vehicle 1000 as an example of an electrical device according to an embodiment of this application.

[0070] 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. Taking the vehicle 1000 as an example, the vehicle 1000 can be a gasoline vehicle, a natural gas vehicle, or a new energy vehicle. New energy vehicles can be pure electric vehicles, hybrid electric vehicles, or range-extended electric vehicles, etc. A battery device 100 is installed inside the vehicle 1000, and the battery device 100 can 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. 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, to meet the power needs of the vehicle 1000 during starting, navigation, and driving.

[0071] In some embodiments, 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.

[0072] Please refer to Figure 2 , Figure 2 This is an exploded structural diagram of a battery device 100 provided in some embodiments of this application. In some embodiments, the battery device 100 includes a housing 10 and a battery cell 20, wherein the battery cell 20 is housed within the housing 10.

[0073] The housing 10 provides a space for housing the battery cell 20, and 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, and together define a space for housing the battery cell 20. The second part 12 may be a hollow structure with one end open, and the first part 11 may be a plate-like structure, with the first part 11 covering the open side of the second part 12 so that the first part 11 and the second part 12 together define the space; alternatively, the first part 11 and the second part 12 may both be hollow structures with one side open, with the open side of the first part 11 covering the open side of the second part 12. Of course, the housing 10 formed by the first part 11 and the second part 12 can be of various shapes, such as a cylinder, a cuboid, etc.

[0074] In the battery device 100, there can be multiple battery cells 20. These multiple battery cells 20 can be connected in series, in parallel, or in a mixed configuration. A mixed configuration means that multiple battery cells 20 are connected in both series and parallel. Multiple battery cells 20 can be directly connected in series, in parallel, or in a mixed configuration, and then the entire assembly of the multiple battery cells 20 is housed within the housing 10. The battery device 100 may also include other structures; for example, it may include a busbar component for electrical connection between the multiple battery cells 20.

[0075] Please see Figure 3 , Figure 3 This is an exploded structural diagram of a battery cell 20 provided in some embodiments of this application. The battery cell 20 includes a top cover 21, a housing 22, a cell 23, and other functional components.

[0076] The top cover 21 is a component that covers the opening of the housing 22 to isolate the internal environment of the battery cell 20 from the external environment. The shape of the top cover 21 can be adapted to the shape of the housing 22 to fit it. Optionally, the top cover 21 can be made of a material with a certain hardness and strength (such as aluminum alloy), so that the top cover 21 is not easily deformed under pressure or impact, allowing the battery cell 20 to have higher structural strength. Functional components such as electrode terminals 21a can be provided on the top cover 21. The electrode terminals 21a can be used for electrical connection with the battery cell 23 to output or input electrical energy to the battery cell 20. In some embodiments, the top cover 21 can also be provided with a pressure relief mechanism for releasing internal pressure when the internal pressure or temperature of the battery cell 20 reaches a threshold. The material of the top cover 21 can also be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and this application embodiment does not impose any special limitations on this. In some embodiments, an insulating element may also be provided on the inner side of the top cover 21 to reduce the risk of short circuit. For example, the insulating element may be made of plastic, rubber, etc.

[0077] The housing 22 is a component used to cooperate with the top cover 21 to form the internal environment of the battery cell 20. This internal environment can accommodate the battery cell 23, electrolyte, and other components. The housing 22 and the top cover 21 can be independent components. An opening can be provided on the housing 22, and the top cover 21 can close the opening to form the internal environment of the battery cell 20. Alternatively, the top cover 21 and the housing 22 can be integrated. Specifically, the top cover 21 and the housing 22 can form a common connecting surface before other components are inserted into the housing. When it is necessary to encapsulate the interior of the housing 22, the top cover 21 closes the housing 22. The housing 22 can be of various shapes and sizes, such as cuboid, cylindrical, hexagonal prism, etc. Specifically, the shape of the housing 22 can be determined according to the specific shape and size of the battery cell 23. The material of the housing 22 can be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc. This application embodiment does not impose any special limitations on this.

[0078] Cell 23 is the component in the battery cell 20 where the electrochemical reaction occurs. The casing 22 may contain one or more cells 23. Cell 23 is mainly formed by winding or stacking positive and negative electrode plates, and a separator is usually provided between the positive and negative electrode plates. The portions of the positive and negative electrode plates containing active material constitute the main body of the cell assembly, while the portions of the positive and negative electrode plates without active material each constitute tabs 23a. The positive and negative tabs may be located together at one end of the main body or at opposite ends of the main body. During the charging and discharging process of the battery device 100, the positive and negative active materials react with the electrolyte, and the tabs 23a connect to the electrode terminals 21a to form a current loop.

[0079] Multiple electrode tabs 23a are stacked to one end of the cell 23 along the Y direction, and then folded to the other end of the cell 23 along the Y direction to connect with the corresponding electrode terminal 21a.

[0080] Please refer to the following: Figure 4 and Figure 5 , Figure 4 This is a schematic cross-sectional view of the battery cell 20 along the Y direction in some embodiments of this application; Figure 5 for Figure 4 Enlarged structural diagram at point A in the middle.

[0081] This application embodiment provides a battery cell 20, which provides bending space for the tab 23a by improving the structure of the top cover 21. Specifically, the battery cell 20 includes a housing 22, a cell 23, and a top cover 21, with the housing 22 having an opening. The cell 23 is disposed inside the housing 22, and a tab 23a is provided at the end of the cell 23 facing the opening. The top cover 21 covers the opening, and a receiving groove 211 is provided on the side of the top cover 21 facing the tab 23a, for receiving the tab 23a. The groove sidewall 2112 of the receiving groove 211 gradually slopes towards the edge of the top cover 21 from the bottom 2111 of the receiving groove 211 towards the opening of the receiving groove 211. Each groove sidewall 2112 of the receiving groove 211 is either flat or protrudes away from the tab 23a.

[0082] The battery cell 20 provided in this application embodiment provides space for the tab 23a by providing a receiving groove 211 on the top cover 21, thereby saving the space height between the cell 23 and the top cover 21. By setting the groove sidewall 2112 of the receiving groove 211 to gradually slope towards the edge of the top cover 21 from the bottom 2111 towards the opening, the receiving space provided by the receiving groove 211 is increased. By setting each groove sidewall 2112 of the receiving groove 211 to be flat or protruding away from the tab 23a, the bending space of the tab provided by the receiving groove 211 is further increased, which helps to solve the problem of the top cover 21 squeezing the tab 23a, reduces the problems of insertion and breakage caused by the tab 23a being squeezed, thereby improving the safety and service life of the battery.

[0083] In some embodiments, the battery cell 20 further includes a lower plastic 24 disposed on the side of the top cover 21 facing the cell 23. The lower plastic 24 at least covers the inner wall of the receiving groove 211 to form insulation between the top cover 21 and the tab 23a.

[0084] Please see Figure 6 and Figure 7 , Figure 6 This is a schematic cross-sectional view of the top cover 21 along the Y direction in some embodiments of this application; Figure 7 for Figure 6 Enlarged structural diagram at point B in the middle.

[0085] In some embodiments, on the cross-section of the sidewall 2112 perpendicular to its extension direction, the connection point between the inner wall surface of the sidewall 2112 and the inner wall surface of the bottom 2111 is designated as P, and the connection point between the inner wall surface of the sidewall 2112 and the surface of the top cover 21 facing the cell 23 is designated as Q. The inner wall surface of the sidewall 2112 coincides with or is located on the side of the line segment PQ away from the tab 23a. The specific shape of the inner wall surface of the sidewall 2112 is not limited, as long as it coincides with or is located on the side of the line segment PQ away from the tab 23a, to reduce pressure on the tab 23a.

[0086] In some embodiments, in a cross-section perpendicular to its extension direction, the inner wall surface of the groove sidewall 2112 is either straight or arc-shaped. When the inner wall surface of the groove sidewall 2112 is straight, it coincides with line segment PQ. When the inner wall surface of the groove sidewall 2112 is arc-shaped, the side of line segment PQ on the inner wall surface of the groove sidewall 2112 that is away from the tab 23a...

[0087] Specifically, when the inner wall surface of the groove sidewall 2112 is arc-shaped, the inner wall surface of the groove sidewall 2112 protrudes from the side away from the tab 23a, and a concave structure is formed on the inner wall surface of the groove sidewall 2112, thereby providing a larger bending space for the tab 23a.

[0088] In some embodiments, the area of ​​the top cover 21 without the receiving groove 211 forms a top cover shoulder 212, which avoids the electrode tab 23a. The top cover shoulder 212 is used to connect to the housing 22 and to provide structures such as the electrode terminal 21a. By providing the top cover shoulder 212 to avoid the electrode tab 23a, the electrode tab 23a is positioned within the receiving groove 211, thus preventing the top cover shoulder 212 from squeezing the electrode tab 23a.

[0089] In some embodiments, the distance from the connection point Q to the edge of the adjacent top cover 21 is set to L1; wherein, 1.5mm≤L1≤3.0mm. By limiting the range of L1, the top cover shoulder 212 can be firmly connected to the housing 22, while providing a larger accommodating space within the receiving groove 211.

[0090] Please see Figure 8 and Figure 9 , Figure 8 This is a schematic diagram of the assembly structure of a battery cell 20 according to some embodiments of this application; Figure 9 This is a schematic diagram showing the disassembled structure of the top cover 21 and the lower plastic 24 according to some embodiments of this application. An electrode terminal 21a is provided on the shoulder 212 of the top cover. The electrode terminal 21a protrudes from the surface of the shoulder 212 away from the cell 23, occupying the height space of the battery cell 20 along the Z direction. To reduce the waste of this height space, in this embodiment, the bottom 2111 of the receiving groove 211 protrudes towards the side of the top cover shoulder 212 away from the cell 23, forming a convex structure 213. By providing the convex structure 213, the bottom 2111 of the receiving groove 211 protrudes towards the outer surface of the top cover shoulder 212, occupying the height space of the portion of the electrode terminal 21a protruding from the top cover shoulder 212, thereby reducing the occupation of the internal space of the casing 22 and thus increasing the energy density of the battery cell 20.

[0091] Specifically, two electrode terminals 21a are disposed at both ends of the top cover 21 along the X direction, and a convex hull structure 213 is disposed between the two electrode terminals 21a. Top cover shoulders 212 are provided around the convex hull structure 213. The top cover shoulders 212 located on both sides of the convex hull structure 213 along the Y direction are relatively narrow, their dimensions meeting the aforementioned numerical range requirement of L1. The top cover shoulders 212 located on both sides of the convex hull structure 213 along the X direction are relatively large, needing to support the electrode terminals 21a and also needing to connect to the housing 22.

[0092] Optionally, the convex structure 213 and the top cover shoulder 212 are configured as an integral structure formed by stamping. By stamping on a sheet material whose size matches that of the top cover 21, the recessed portion forms a receiving groove 211, and the other portion forms the top cover shoulder 212. During stamping, the portion forming the top cover shoulder 212 is clamped by a jig to achieve positioning and fixation of the sheet material.

[0093] In some embodiments, the outer surface of the bottom of the tank 2111 is not higher than the electrode terminal 21a. This arrangement can make full use of the height space occupied by the electrode terminal 21a, without increasing the height of the battery cell 20 along the Z direction.

[0094] Please return to the reference. Figure 6 and Figure 7 In some embodiments, the height difference between the convex bulge structure 213 and the top cover shoulder 212 is set to ΔH; where 0mm < ΔH ≤ 4.0mm. The value range of ΔH is specifically set according to parameters such as the distance of the electrode terminal 21a above the top cover shoulder 212 and the required accommodating space of the electrode tab 23a.

[0095] In some embodiments, the minimum distance from the convex structure 213 to the edge of the top cover shoulder 212 is set to L2; where 1.5mm≤L2≤3.0mm. By setting the range of L2, a safe distance is maintained between the welded joint of the top cover shoulder 212 and the lower plastic 24, which helps to avoid burning the lower plastic 24 during welding. At the same time, maintaining a larger distance between the top cover shoulder 212 and the convex structure 213 allows the receiving groove 211 to have a larger capacity, thereby improving the capacity to accommodate the tab 23a.

[0096] In some embodiments, the wall thickness T of the sidewall 2112 of the receiving groove 211 is not greater than the thickness of the bottom 2111 of the receiving groove 211. When processing the receiving groove 211, it is processed by stamping. The sidewall 2112 is stretched by the stamping and has a smaller wall thickness T compared to the bottom 2111.

[0097] Optionally, the thickness of the bottom 2111 of the receiving groove 211 is generally set to 1.5mm or more. Within this range, the convex hull structure 213 can have good structural strength and is not easily deformed.

[0098] Specifically, the wall thickness T of the channel sidewall 2112 is set to T≥1.2mm. Within this range, the channel sidewall 2112 has high structural strength to reduce the deformation of the top cover 21.

[0099] In some embodiments, a rounded corner is provided at the connection between the surface of the top cover shoulder 212 facing the cell 23 and the slot sidewall 2112; and / or, a rounded corner is provided at the connection between the slot sidewall 2112 and the slot bottom 2111. By rounding the corners, the slot bottom 2111, the slot sidewall 2112, and the top cover shoulder 212 are smoothly connected, which helps to reduce damage to the tab 23a and provides good protection for the tab 23a.

[0100] The battery cell 20 provided in this embodiment includes a housing 22, a battery cell 23, and a top cover 21. The housing 22 has an opening. The battery cell 23 is disposed inside the housing 22, and a tab 23a is provided at the end of the battery cell 23 facing the opening. The top cover 21 covers the opening. The top cover 21 includes a top cover shoulder 212 and an outwardly protruding convex structure 213. A receiving groove 211 is formed on the inner side of the convex structure 213, which is used to receive the tab 23a. The groove sidewall 2112 of the receiving groove 211 gradually slopes towards the edge of the top cover 21 from the groove bottom 2111 towards the groove opening of the receiving groove 211. Each groove sidewall 2112 of the receiving groove 211 is either flat or protrudes away from the tab 23a. By providing an outwardly protruding receiving groove 211 on the top cover 21, receiving space is provided for the tab 23a, thereby saving space height between the battery cell 23 and the top cover 21. By configuring the sidewalls 2112 of the receiving groove 211 to gradually slope towards the edge of the top cover 21 from the bottom 2111 towards the opening, the receiving space provided by the receiving groove 211 is increased. By configuring each sidewall 2112 of the receiving groove 211 to be flat or protruding away from the tab 23a, the bending space provided by the receiving groove 211 for the tab is further increased, which helps to solve the problem of the top cover 21 squeezing the tab 23a, reduces the problems of insertion and breakage caused by the tab 23a being squeezed, and thus improves the safety and service life of the battery.

[0101] This application also provides a battery device 100, including a battery cell 20 as described in the above embodiment.

[0102] This application also provides an electrical device, including a battery device 100 as described in the above embodiment, the battery device 100 being used to provide electrical energy.

[0103] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and not to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application, and they should all be covered within the scope of the claims and specification of this application. In particular, as long as there is no structural conflict, the various technical features mentioned in the embodiments can be combined in any way. 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 battery cell includes: A housing (22) having an opening; A battery cell (23) is disposed inside the housing (22); a tab (23a) is provided at one end of the battery cell (23) facing the opening. A top cover (21) is provided over the opening; the top cover (21) has a receiving groove (211) on the side facing the electrode (23a), the receiving groove (211) is used to receive the electrode (23a); the groove sidewall (2112) of the receiving groove (211) gradually slopes towards the edge of the top cover (21) from the bottom (2111) of the receiving groove (211) towards the opening of the receiving groove (211); The sidewalls (2112) of each of the receiving grooves (211) are configured as planes or protrude in a direction away from the tabs (23a).

2. The battery cell of claim 1, wherein, On the cross section of the sidewall (2112) perpendicular to its extension direction, the connection point between the inner wall surface of the sidewall (2112) and the inner wall surface of the bottom (2111) is set as P, and the connection point between the inner wall surface of the sidewall (2112) and the surface of the top cover (21) facing the cell (23) is set as Q; the inner wall surface of the sidewall (2112) coincides with the line segment PQ or is located on the side of the line segment PQ away from the tab (23a).

3. The battery cell of claim 2, wherein, On the cross section of the groove sidewall (2112) perpendicular to its extension direction, the inner wall surface of the groove sidewall (2112) is straight or arc-shaped.

4. The battery cell of claim 3, wherein, When the inner wall surface of the groove sidewall (2112) is arc-shaped, the inner wall surface of the groove sidewall (2112) protrudes to the side away from the tab (23a).

5. The battery cell of any one of claims 2-4, wherein, The area of ​​the top cover (21) where the receiving groove (211) is not provided forms a top cover shoulder (212), which avoids the tab (23a).

6. The battery cell of claim 5, wherein, The distance from the connection point Q to the edge of the adjacent top cover (21) is set as L1; wherein, 1.5mm≤L1≤3.0mm.

7. The battery cell of claim 5, wherein, The top cover shoulder (212) is provided with an electrode terminal (21a), which protrudes from the surface of the top cover shoulder (212) away from the battery cell (23); The bottom (2111) of the receiving groove (211) protrudes toward the side of the top cover shoulder (212) away from the battery cell (23), forming a convex hull structure (213).

8. The battery cell of claim 7, wherein, The outer surface of the bottom of the groove (2111) is not higher than the electrode terminal (21a).

9. The battery cell of claim 7, wherein, The height difference between the convex hull structure (213) and the top cover shoulder (212) is set as △H; where 0mm<△H≤4.0mm.

10. The battery cell of claim 7, wherein, The minimum distance from the convex hull structure (213) to the edge of the top cover shoulder (212) is set to L2; wherein, 1.5mm≤L2≤3.0mm.

11. The battery cell of any one of claims 1-4, wherein, The wall thickness T of the sidewall (2112) of the receiving groove (211) is not greater than the thickness of the bottom (2111) of the receiving groove (211).

12. The battery cell of claim 11, wherein, The wall thickness T of the groove sidewall (2112) is set to T≥1.2mm.

13. The battery cell of claim 5, wherein, The top cover shoulder (212) is provided with a fillet at the connection between the surface of the electric core (23) and the groove side wall (2112); and / or The groove side wall (2112) is provided with a fillet at the connection with the groove bottom (2111).

14. A battery device characterized by comprising: A battery device (100) comprising the battery cell (20) according to any one of claims 1 to 13.

15. An electrical device, comprising: A battery device (100) according to claim 14, wherein the battery device (100) is configured to provide electrical energy.

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