Battery monomer, battery device and electric equipment

Abstract

The utility model provides a battery monomer, a battery device and electric equipment. The battery monomer comprises a shell, an end cover, an electrode assembly and an adapter plate, the end cover is provided with an electrode terminal, the electrode assembly is accommodated in the shell, the electrode assembly comprises at least three groups of laminated tab parts, and the adapter plate is electrically connected with the at least three groups of laminated tab parts and the electrode terminal; wherein the switching piece comprises a plurality of tab welding parts in the first direction, and a tab welding area is arranged on the surface of one side of each tab welding part. According to the present invention, the plurality of tab welding parts are arranged in the first direction of the adapter plate, such that the path of the current conducted from the electrode assembly to the electrode terminal can be dispersed, the local resistance can be reduced, and the centralized generation of the heat can be reduced so as to easily improve the rapid charging performance of the battery.

Description

Technical Field

[0001] This application relates to the technical field of batteries, and particularly to a battery cell, a battery device, and an electrical device. Background Art

[0002] With the increasing demands of people, batteries are gradually developing towards fast charging, long life, high energy density, and high safety. By increasing the size of the battery, the capacity of the battery can be significantly increased. However, after the size of the battery increases, since the current density also increases accordingly, the temperature rise during the charging and discharging process of the battery also increases, thereby affecting the fast charging performance of the battery. Summary of the Utility Model

[0003] In view of this, the main technical problem to be solved by this application is how to improve the fast charging performance of the battery.

[0004] To solve the above technical problem, in the first aspect of this application, a battery cell is provided. The battery cell includes a housing, an end cap, an electrode assembly, and a connecting piece; the end cap is provided with an electrode terminal, the electrode assembly is received in the housing, the electrode assembly includes at least three sets of stacked tab portions, and the connecting piece is electrically connected to multiple sets of stacked tab portions and the electrode terminal; wherein, the connecting piece includes a plurality of tab welding portions in a first direction, the first direction is the length direction of the battery cell, and one side surface of the tab welding portion is provided with a tab welding area.

[0005] In the technical solution of the embodiment of this application, by setting that the electrode assembly includes at least three sets of stacked tab portions and connecting them to the tab welding areas on the plurality of tab welding portions of the connecting piece, the contact area between the tab portions and the connecting piece is significantly increased. This setting can, on the one hand, make full use of the space in the housing to achieve a higher density of electrical connection, and on the other hand, can disperse the path of the current conducting from the electrode assembly to the electrode terminal, reduce the local resistance, and reduce the concentrated generation of heat, thereby effectively improving the high-current discharge performance of the battery and delaying the life attenuation caused by overheating, which is beneficial to improving the fast charging performance of the battery.

[0006] In some embodiments, the tab welding portion includes two correspondingly arranged tab welding areas in a second direction, and the second direction is the width direction of the battery cell.

[0007] In the embodiments of the present application, by providing two corresponding tab welding areas in the second direction of the tab welding part, on the one hand, two electrode assemblies can be connected by using one adapter plate, thus simplifying the production process; on the other hand, the adapter plate can form a bilateral fixing structure through two tab parts in the second direction connected thereto. This symmetric design can balance the distribution of welding stress and reduce the risk of deformation or cracking caused by unilateral welding. Especially when the tab parts expand and contract during the charging and discharging process of the battery, the bilateral welding can effectively disperse the mechanical stress and improve the anti-fatigue performance of the connection, thereby being beneficial to improving the stability of the battery.

[0008] In some embodiments, the area ratio of the tab welding area to one side surface of the tab welding part is 40% - 60%.

[0009] In the embodiments of the present application, by adopting the above technical solution, the tab part and the adapter plate can have sufficient contact area to reduce the contact resistance, and at the same time, the non-welding area can be reserved to maintain the structural integrity of the adapter plate, reducing the problem of welding stress concentration caused by too large welding area, which is beneficial to improving the stability of the battery.

[0010] In some embodiments, the adapter plate includes at least one connecting part, and the connecting part is used to connect adjacent tab welding parts.

[0011] In the embodiments of the present application, by providing that the adapter plate includes a connecting part, adjacent tab welding parts can be connected into an integrated adapter plate structure. In addition, the connecting part can serve as a buffer between adjacent tab welding parts, effectively diffusing the current and the generated heat of the tab welding part, reducing the local accumulation of heat, and thus being beneficial to improving the fast charging performance of the battery.

[0012] In some embodiments, the end cover is provided with at least one positioning part, and the adapter plate is provided with at least one positioning area, and the positioning part and the positioning area are arranged in one-to-one correspondence.

[0013] In the embodiments of the present application, by adopting the above technical solution, the spatial alignment relationship between the adapter plate, the tab part and the electrode terminal can be improved, reducing the manual calibration time and the problems of poor welding of the tab or misalignment of the electrode terminal caused by assembly deviation, which is beneficial to improving the automation production efficiency and the reliability of the electrical connection.

[0014] In some embodiments, the positioning area is arranged on the connecting part.

[0015] In the embodiments of the present application, by further limiting the positioning area on the connecting part, the occupation of the welding part space by the positioning area can be reduced, thereby reducing the probability of interference of the positioning area in the welding process of the adapter plate.

[0016] In some embodiments, the positioning area is a first notch structure formed by inward depression of the edge of the connecting portion.

[0017] In the embodiments of the present application, by adopting the above technical solutions, a notch structure can be directly formed at the edge of the connecting portion by processes such as stamping, without the need to additionally add positioning components, which is beneficial to improving the automation production efficiency and reducing the production cost. In addition, by providing a notch structure in the connecting portion, the cross-sectional area of the current passing through the connecting portion is reduced, that is, the resistance of the connecting portion increases at this time. Therefore, when the current is greater than a certain threshold, according to Joule's law, the connecting portion can be thermally fused first compared to other parts of the adapter plate, which is beneficial to reducing the risk of thermal runaway of the battery due to overheating.

[0018] In some embodiments, the connecting portion is further provided with a protection hole, which is located between adjacent tab welding portions. When the current flowing through the adapter plate is greater than a preset threshold, the connecting portion is thermally fused.

[0019] In the embodiments of the present application, by providing a protection hole in the connecting portion, the cross-sectional area of the connecting portion is relatively reduced, that is, the resistance of the connecting portion increases. According to Joule's law, the connecting portion can be thermally fused first compared to other parts of the adapter plate, which is beneficial to reducing the risk of thermal runaway of the battery due to overheating.

[0020] In some embodiments, an electrode terminal welding portion is formed at one end of the adapter plate, the electrode terminal welding portion is connected to an adjacent tab welding portion, and an electrode terminal welding area is formed on one side surface of the electrode terminal welding portion.

[0021] In the embodiments of the present application, by adopting the above technical solutions, a specific area can be provided for the connection between the adapter plate and the electrode terminal, so that the electrode assembly can be electrically connected to the electrode terminal through the adapter plate.

[0022] In some embodiments, the end cap is provided with a liquid injection hole, and the battery cell includes two adapter plates. An avoidance area is provided at one end of one of the adapter plates away from the electrode terminal welding area, and the avoidance area is correspondingly arranged with the liquid injection hole.

[0023] In the embodiments of the present application, by providing an avoidance area corresponding to the liquid injection hole on the adapter plate, the shielding of the liquid injection hole by the adapter plate is effectively reduced, so that the electrolyte can be smoothly injected into the battery, which is beneficial to improving the uniformity of liquid injection and the production efficiency.

[0024] In some embodiments, the avoidance area is a second notch structure formed by inward depression of the edge of the adapter plate.

[0025] In the embodiments of the present application, by adopting the above technical solutions, a notch structure can be directly formed at the edge of the adapter plate by processes such as stamping, which is beneficial to improving the automation production efficiency and reducing the production cost.

[0026] In some embodiments, a bending portion is provided between the electrode terminal welding portion and the adjacent tab welding portion. The bending portion is bent from the tab welding portion toward the side of the electrode assembly, and the electrode terminal welding portion is connected to the adjacent tab welding portion through the bending portion.

[0027] In the embodiments of the present application, by providing a bending portion between the electrode terminal welding portion and the adjacent tab welding portion, and the bending portion is bent from the tab welding portion toward the side of the electrode assembly, a gap is left between the electrode terminal welding portion and the end cover, so that more space can be reserved for the placement of the electrode terminal. For example, the size of the electrode terminal can be further increased, thereby increasing the current-carrying capacity of the electrode terminal, which is beneficial to improving the fast charging performance of the battery.

[0028] In some embodiments, the electrode terminal welding area includes a protruding portion protruding toward the electrode terminal, and the protruding portion is electrically connected to the electrode terminal.

[0029] In the embodiments of the present application, by adopting the above technical solution, on the one hand, the setting of the protruding portion can quickly align the electrode terminal through visual recognition or mechanical positioning, improving the automation degree and assembly efficiency of the production line; on the other hand, the setting of the protruding portion also significantly increases the contact area between the electrode terminal welding area and the electrode terminal, thereby reducing the contact resistance between the two, which is beneficial to reducing the energy loss during current conduction, and thus is beneficial to improving the fast charging performance of the battery.

[0030] In some embodiments, a hollow area is provided in the included angle area between adjacent sides of the adapter plate.

[0031] In the embodiments of the present application, since the battery cell usually includes two adapter plates, namely a positive adapter plate and a negative adapter plate, by providing hollow areas in the corresponding included angle areas of the positive and negative adapter plates, an anti-misoperation function can be achieved. For example, the hollow area of the positive adapter plate is located in the lower left corner area, and the hollow area of the negative adapter plate is located in the lower right corner area. Thus, the positive and negative adapter plates can be quickly distinguished on the production line, reducing human operation errors, which is beneficial to improving the production efficiency and assembly accuracy.

[0032] In the second aspect of the present application, a battery device is provided, including the battery cell provided in the first aspect. The battery device provided by the embodiment of the present application, since it includes the battery cell provided in the first aspect, at least has the same advantages as the battery cell provided in the first aspect.

[0033] In the third aspect of the present application, an electrical equipment is provided, including the battery device provided in the second aspect. The electrical equipment provided by the embodiment of the present application, since it also includes the battery cell provided in the first aspect, at least has the same advantages as the battery cell provided in the first aspect. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] To more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the accompanying drawings required for the description of the embodiments. Obviously, the accompanying drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other accompanying drawings can be obtained based on these drawings.

[0035] Figure 1 is a schematic diagram of the disassembly structure of a battery cell provided by an embodiment of the present application;

[0036] Figure 2 is a schematic diagram of the structure of the first embodiment of the adapter provided by an embodiment of the present application;

[0037] Figure 3 is a schematic diagram of the structure of the second embodiment of the adapter provided by an embodiment of the present application;

[0038] Figure 4 is a schematic diagram of the structure of the third embodiment of the adapter provided by an embodiment of the present application;

[0039] Figure 5 is a schematic diagram of the structure of the fourth embodiment of the adapter provided by an embodiment of the present application;

[0040] Figure 6 is a schematic diagram of the structure of the connection between the adapter and the end cap provided by an embodiment of the present application;

[0041] Figure 7 is a schematic diagram of another angle of the adapter provided by an embodiment of the present application;

[0042] Figure 8 is a schematic diagram of the disassembly structure of the battery device provided by an embodiment of the present application;

[0043] Figure 9 is a schematic diagram of the structure of the electrical equipment provided by an embodiment of the present application.

[0044] Main reference numerals description:

[0045] Electrical equipment 1000; Battery device 100; Controller 200; Motor 300; Box body 10; First part 11; Second part 12; Battery cell 20; End cap 21; Electrode terminal 21a; Positioning part 21b; Liquid injection hole 21c; Housing 22; Electrode assembly 23; Tab 23a; Adapter 24; Tab welding part 241; Tab welding area 241a; Connection part 242; Protection hole 242a; Positioning area 243; Electrode terminal welding part 244; Electrode terminal welding area 244a; Protrusion 244b; Avoidance area 245; Bending part 246; Hollow area 247. Specific embodiments

[0046] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present application without creative efforts shall fall within the scope of protection of the present application.

[0047] The terms "first", "second", and "third" in the present application are only used for descriptive purposes and cannot be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first", "second", and "third" may explicitly or implicitly include at least one such feature. In the description of the present application, the meaning of "a plurality" is at least two, such as two, three, etc., unless otherwise specifically defined. All directional indications (such as up, down, left, right, front, back...) in the embodiments of the present application are only used to explain the relative positional relationship and movement conditions between components in a specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indications will also change accordingly. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or units is not limited to the listed steps or units, but optionally further includes steps or units not listed, or optionally further includes other steps or units inherent to these processes, methods, products, or devices.

[0048] The "scope" disclosed in this application is defined in the form of a lower limit and an upper limit. A given scope is defined by selecting a lower limit and an upper limit, and the selected lower limit and upper limit define the boundaries of a particular scope. The scope defined in this way can include the end values or not include the end values, and can be combined arbitrarily, that is, any lower limit can be combined with any upper limit to form a scope. For example, if ranges of 60 to 120 and 80 to 110 are listed for a specific parameter, ranges of 60 to 110 and 80 to 120 are also contemplated. In addition, if the minimum range values 1 and 2 are listed, and if the maximum range values 3, 4, and 5 are listed, then the following ranges are all contemplated: 1 to 3, 1 to 4, 1 to 5, 2 to 3, 2 to 4, and 2 to 5. In this application, unless otherwise specified, the numerical range "a to b" represents an abbreviated representation of any real number combination between a and b, where both a and b are real numbers. For example, the numerical range "0 to 5" means that all real numbers between "0 to 5" have been fully listed herein, and "0 to 5" is only an abbreviated representation of these numerical combinations. Additionally, when stating that a certain parameter is an integer ≥2, it is equivalent to disclosing that the parameter is, for example, the integers 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc.

[0049] Reference to "embodiments" in this context means that the particular features, structures, or characteristics described in connection with the embodiments can be included in at least one embodiment of this application. The phrase appears in various places in the specification and does not necessarily refer to the same embodiment each time, nor is it an independent or alternative embodiment mutually exclusive with other embodiments. Those skilled in the art will explicitly and implicitly understand that the embodiments described herein can be combined with other embodiments.

[0050] In the description of the embodiments of this application, the term "and / or" is merely a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. Additionally, the character " / " in this document generally indicates that the associated objects before and after are in an "or" relationship.

[0051] In the description of the embodiments of this application, unless otherwise clearly specified and limited, technical terms such as "installation", "connection", "connection", "fixation", etc. should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or integrated; it can also be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and can be the communication inside two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of this application can be understood according to specific circumstances.

[0052] At present, from the perspective of market development, the application of batteries is becoming more and more extensive. Batteries are not only used in energy storage power systems such as hydropower, thermal power, wind power and solar power stations, but also widely used in electric vehicles such as electric bicycles, electric motorcycles, electric cars, as well as military equipment and aerospace and other fields. With the continuous expansion of battery application areas, its market demand is also constantly expanding.

[0053] In the related art, an electrode assembly and a transfer plate are provided in a battery cell. An electrode assembly usually includes two pole ears, namely a positive pole ear and a negative pole ear, and the pole ears are composed of a plurality of stacked pole ears. The transfer plate is used to conduct the electrode assembly with the electrode terminal. An transfer plate usually includes an electrode terminal welding area and two symmetrically arranged pole ear welding areas. A pole ear is electrically connected to the connecting plate through a pole ear welding area. As users' demand for battery performance gradually increases, the size of the battery is also increasing. For example, for square batteries, the size of the battery in the length direction continues to increase, thus forming a "long and thin" battery structure. However, as the size of the battery increases, the current generated in the battery also increases, that is, the current density passing through the tab assembly and the adapter also increases. According to Joule's law, at a higher current density, the adapter will also generate greater Joule heat. When the adapter has a high temperature, other components in the battery, such as plastic parts, may be melted by the adapter, resulting in direct contact between the adapter and the end cap, causing the risk of short circuit, thereby causing thermal runaway of the battery during charging and discharging. Therefore, how to further improve the battery's overcurrent capacity and thus improve the battery's fast charging performance is a technical problem that needs to be solved urgently.

[0054] In order to further improve the fast charging performance of the battery, research has found that multiple groups of pole ears can be set on the electrode assembly and multiple pole ear welding parts can be set on the adapter, so that the contact area between the electrode assembly and the adapter is significantly increased, and the path of current conduction from the electrode assembly to the electrode terminal is effectively dispersed, which is beneficial to improving the battery's current capacity, and then beneficial to improving the battery's fast charging performance.

[0055] Based on the above considerations, please refer to Figures 1 to 2 , Figure 1 is a schematic diagram of the exploded structure of a battery cell 20 provided in an embodiment of the present application, Figure 2It is a schematic structural diagram of the first embodiment of the adapter piece 24 provided by the embodiment of the present application. In the first aspect of the present application, a battery cell 20 is provided. The battery cell 20 includes a housing 22, an end cap 21, an electrode assembly 23, and an adapter piece 24. The end cap 21 is provided with electrode terminals 21a. The electrode assembly 23 is housed in the housing 22. The electrode assembly 23 includes at least three sets of stacked tab portions 23a. The adapter piece 24 is electrically connected to at least three sets of stacked tab portions 23a and the electrode terminals 21a. Among them, the adapter piece 24 includes a plurality of tab welding portions 241 in a first direction, and a tab welding area 241a is provided on one surface of the tab welding portion 241.

[0056] The structure of the electrode assembly 23 provided by the embodiment of the present application includes, but is not limited to, a wound core structure formed by winding a positive electrode plate and a negative electrode plate, and a stacked core structure formed by alternately stacking a plurality of positive electrode plates and a plurality of negative electrode plates. Only one electrode assembly 23 can be housed in the housing 22, or a plurality of electrode assemblies 23 can be housed. The electrode terminals 21a include a positive electrode terminal and a negative electrode terminal. In the first direction (the length direction of the battery cell 20, the A-B direction in the drawing), the positive electrode terminal and the negative electrode terminal are arranged at intervals. The tab portions 23a are formed by stacking a plurality of tabs. The sizes of different tab portions 23a can be the same or different. In the first direction, the tab portions 23a are arranged at intervals, and the interval distances between different tab portions 23a can be the same or different. Those skilled in the art can set according to actual needs.

[0057] Schematically, at least three sets of stacked tab portions 23a are divided into positive tab portions and negative tab portions. The positive tab portions include a plurality of stacked positive tabs, and the negative tab portions include a plurality of stacked negative tabs. It can be understood that on one electrode assembly 23, the number of at least one type of tab portion 23a is at least two. For example, the tab portions 23a of an electrode assembly 23 can include two positive tab portions and one negative tab portion, or include one positive tab portion and two negative tab portions, or include two positive tab portions and two negative tab portions, or include three positive tab portions and three negative tab portions. Those skilled in the art can set according to actual needs.

[0058] The adapter piece 24 is electrically connected to at least three sets of stacked tab portions 23a, that is, at least three tab welding areas 241a are provided on one adapter piece 24, and each tab portion 23a is electrically connected to the adapter piece 24 through the corresponding tab welding area 241a. Exemplarily, the tab portion 23a and the adapter piece 24 can be electrically connected by, but not limited to, ultrasonic welding or laser welding.

[0059] The adapter piece 24 can be, but is not limited to, a conductive metal sheet such as a copper sheet or an aluminum sheet, or a composite sheet structure of two or more conductive metals such as a copper-aluminum composite sheet.

[0060] It should be noted that in the embodiments of the present application, the first direction and the second direction are specifically defined with reference to the orientation when the battery cell 20 is placed on a flat tabletop with its end cap 21 facing upward. The up-down direction is the height direction of the battery cell 20. In the plane where the end cap 21 is located, the arrangement direction of the positive electrode terminal and the negative electrode terminal is the first direction (the A-B direction in the drawings), which is also the length direction of the battery cell 20. The direction perpendicular to the length direction is the second direction (the C-D direction in the drawings), which is also the width direction of the battery cell 20. The height direction, the width direction, and the length direction are perpendicular to each other pairwise.

[0061] In the technical solution of the embodiments of the present application, by providing that the electrode assembly 23 includes at least three sets of stacked tab portions 23a and connecting them to the tab welding areas 241a on multiple tab welding portions 241 of the adapter plate 24, the contact area between the tab portions 23a and the adapter plate 24 is significantly increased. This arrangement can, on the one hand, make full use of the space inside the housing 22 to achieve a higher density of electrical connection, and on the other hand, can disperse the path of current conduction from the electrode assembly 23 to the electrode terminal 21a, reduce the local resistance, and reduce the concentrated generation of heat, thereby effectively improving the high-current discharge performance of the battery cell 20 and delaying the life attenuation caused by overheating, which is beneficial to improving the fast charging performance of the battery cell 20.

[0062] In some embodiments, as Figure 2 shown, the tab welding portion 241 includes two correspondingly arranged tab welding areas 241a in the second direction.

[0063] In the embodiments of the present application, by providing two corresponding tab welding areas 241a in the second direction of the tab welding portion 241, on the one hand, two electrode assemblies 23 can be connected using one adapter plate 24, thus simplifying the production process; on the other hand, the adapter plate 24 can form a bilateral fixed structure through two tab portions 23a in the second direction connected thereto. This symmetric design can balance the distribution of welding stress and reduce the risk of deformation or cracking caused by unilateral welding. Especially when the tab portions 23a expand and contract during the charging and discharging process of the battery cell 20, the bilateral welding can effectively disperse the mechanical stress and improve the anti-fatigue performance of the connection, which is beneficial to improving the stability of the battery cell 20.

[0064] In some embodiments, the area ratio of the tab welding area 241a to one side surface of the tab welding portion 241 is 40% - 60%.

[0065] In the embodiments of the present application, by adopting the above technical solutions, the ear part 23a and the adapter piece 24 can have a sufficient contact area to reduce the contact resistance. At the same time, the non-welded area can be retained to maintain the structural integrity of the adapter piece 24, reducing the problem of welding stress concentration caused by too large a welding area, which is beneficial to improving the stability of the battery cell 20.

[0066] Exemplarily, the area ratio of the ear welding area 241a to one side surface of the ear welding part 241 can be 40%, 44%, 48%, 52%, 56%, 60%, etc., or a range composed of any two of the above values. For example, 40% - 48%, 48% - 52%, 52% - 60%, etc.

[0067] In some embodiments, please refer to Figure 2 and Figure 3 , Figure 3 which is a schematic structural diagram of the second embodiment of the adapter piece 24 provided by the embodiments of the present application. The adapter piece 24 includes at least one connecting part 242, and the connecting part 242 is used to connect adjacent ear welding parts 241.

[0068] In the embodiments of the present application, by providing that the adapter piece 24 includes the connecting part 242, adjacent ear welding parts 241 can be connected into one body to form an integral adapter piece 24 structure. In addition, the connecting part 242 can serve as a buffer part between adjacent ear welding parts 241, effectively diffusing the current and the generated heat of the ear welding parts 241, reducing the local accumulation of heat, which is beneficial to improving the fast charging performance of the battery cell 20.

[0069] The connecting part 242 and the adjacent ear welding part 241 can be independent structures respectively, or can be an integrally formed structure. It can be understood that when the connecting part 242 and the adjacent ear welding part 241 are independent structures, the combination of the connecting part 242 and the ear welding part 241 can be flexibly matched according to the number of ear parts 23a of the electrode assembly 23, so as to meet the adaptation requirements for different structural electrode assemblies 23. When the connecting part 242 and the adjacent ear welding part 241 are integrally formed structures, on the one hand, this integrally formed structure is beneficial to improving the overall stability of the adapter piece 24, and on the other hand, it can reduce the contact resistance between the connecting part 242 and the adjacent ear welding part 241, improve the current conduction efficiency, and is beneficial to reducing energy loss.

[0070] Optionally, in the first direction, the ratio of the length of the tab welding portion 241 to the length of the connecting portion 242 is 3:8 to 12:1. Exemplarily, in the first direction, the ratio of the length of the tab welding portion 241 to the length of the connecting portion 242 can be 3:8, 1:1, 2:1, 5:1, 10:1, 12:1, etc., or a range composed of any two of the above values. For example, 3:8 to 2:1, 2:1 to 5:1, 5:1 to 12:1, etc.

[0071] Optionally, in the first direction, the length of the tab welding portion 241 is 15 mm to 60 mm. Exemplarily, in the first direction, the length of the tab welding portion 241 can be 15 mm, 25 mm, 35 mm, 45 mm, 55 mm, 60 mm, etc., or a range composed of any two of the above values. For example, 15 mm to 35 mm, 35 mm to 45 mm, 45 mm to 60 mm, etc.

[0072] Optionally, in the first direction, the length of the connecting portion 242 is 5 mm to 40 mm. Exemplarily, in the first direction, the length of the connecting portion 242 can be 5 mm, 10 mm, 15 mm, 25 mm, 35 mm, 40 mm, etc., or a range composed of any two of the above values. For example, 5 mm to 15 mm, 15 mm to 25 mm, 25 mm to 60 mm, etc.

[0073] Optionally, in the first direction, the length of the adapter piece 24 is 80 mm to 280 mm. Exemplarily, in the first direction, the length of the adapter piece 24 can be 80 mm, 100 mm, 150 mm, 200 mm, 250 mm, 280 mm, etc., or a range composed of any two of the above values. For example, 80 mm to 150 mm, 150 mm to 200 mm, 200 mm to 280 mm, etc. Optionally, in the second direction, the length of the adapter piece 24 is 18 mm to 78 mm. Exemplarily, in the second direction, the length of the adapter piece 24 can be 18 mm, 28 mm, 38 mm, 48 mm, 58 mm, 68 mm, 78 mm, etc., or a range composed of any two of the above values. For example, 18 mm to 38 mm, 38 mm to 58 mm, 58 mm to 78 mm, etc.

[0074] In some embodiments, please refer to Figure 6 , Figure 6 which is a schematic structural diagram of the connection between the adapter piece 24 and the end cap 21 provided by the embodiment of the present application. The end cap 21 is provided with at least one positioning portion 21b, and the adapter piece 24 is provided with at least one positioning area 243. The positioning portion 21b and the positioning area 243 are arranged in one-to-one correspondence.

[0075] In the embodiments of the present application, by adopting the above technical solutions, the spatial alignment relationship between the adapter piece 24, the pole ear part 23a, and the electrode terminal 21a can be improved, the manual calibration time and the problems of poor soldering of the pole ear part 23a or misalignment of the electrode terminal 21a caused by assembly deviation can be reduced, which is beneficial to improving the automated production efficiency and the reliability of electrical connection.

[0076] Optionally, the positioning part 21b is a columnar, square, or irregular three-dimensional structure protruding towards the adapter piece; the positioning area 243 is circular, square, or irregular in shape.

[0077] In some embodiments, as Figure 2 shown, the positioning area 243 is provided on the connecting part 242.

[0078] In the embodiments of the present application, by further defining the positioning area 243 on the connecting part 242, the occupation of the space of the welding part by the positioning area 243 can be reduced, thereby reducing the probability of interference of the positioning area 243 with the welding process of the adapter piece 24.

[0079] In some embodiments, as Figure 2 shown, the positioning area 243 is a first notch structure formed by the edge of the connecting part 242 being recessed inward.

[0080] In the embodiments of the present application, by adopting the above technical solutions, a notch structure can be directly formed on the edge of the connecting part 242 by processes such as stamping without additionally adding positioning components, which is beneficial to improving the automated production efficiency and reducing the production cost. In addition, by providing a notch structure on the connecting part 242, the cross-sectional area of the current passing through the connecting part 242 is reduced, that is, the resistance of the connecting part 242 increases at this time. Therefore, when the current is greater than a certain threshold, according to Joule's law, the connecting part 242 can be thermally melted first compared with other parts of the adapter piece 24, which is beneficial to reducing the risk of thermal runaway of the battery cell 20 due to overheating.

[0081] In some embodiments, please refer to Figure 4 , Figure 4 which is a schematic structural diagram of the third embodiment of the adapter piece 24 provided by the embodiments of the present application. The connecting part 242 is further provided with a protection hole 242a, and the protection hole 242a is located between adjacent pole ear welding parts 241. When the current flowing through the adapter piece 24 is greater than a preset threshold, the connecting part 242 is thermally melted.

[0082] In the embodiments of the present application, by providing a protection hole 242a in the connecting part 242, the cross-sectional area of the connecting part 242 is relatively reduced, that is, the resistance of the connecting part 242 increases. According to Joule's law, the connecting part 242 can be thermally melted first compared with other parts of the adapter piece 24, which is beneficial to reducing the risk of thermal runaway of the battery cell 20 due to overheating.

[0083] In some embodiments, such as Figure 4 shown, one end of the adapter plate 24 is formed with an electrode terminal welding portion 244, the electrode terminal welding portion 244 is connected to the adjacent tab welding portion 241, and an electrode terminal welding area 244a is formed on one side surface of the electrode terminal welding portion 244.

[0084] The electrode terminal welding portion 244 and the adjacent tab welding portion 241 can be two independent structures or an integrally formed structure.

[0085] In the embodiments of the present application, by adopting the above technical solution, a specific area can be provided for the connection between the adapter plate 24 and the electrode terminal 21a, so that the electrode assembly 23 can be electrically connected to the electrode terminal 21a through the adapter plate 24.

[0086] In some embodiments, such as Figure 4 and Figure 6 shown, the end cap 21 is provided with a liquid injection hole 21c, the battery cell 20 includes two adapter plates 24, and one end of one of the adapter plates 24 away from the electrode terminal welding area 244a is provided with an avoidance area 245, and the avoidance area 245 is correspondingly arranged with the liquid injection hole 21c.

[0087] In the embodiments of the present application, by providing the avoidance area 245 corresponding to the liquid injection hole 21c on the adapter plate 24, the shielding of the liquid injection hole 21c by the adapter plate 24 is effectively reduced, so that the electrolyte can be smoothly injected into the battery cell 20, which is beneficial to improving the uniformity of liquid injection and production efficiency.

[0088] Optionally, the avoidance area 245 is circular, square, or irregular in shape.

[0089] In some embodiments, such as Figure 4 shown, the avoidance area 245 is a second notch structure formed by the edge of the adapter plate 24 being recessed inward.

[0090] In the embodiments of the present application, by adopting the above technical solution, a notch structure can be directly formed on the edge of the adapter plate 24 by processes such as stamping, which is beneficial to improving the automation production efficiency and reducing the production cost.

[0091] In some embodiments, such as Figure 5 shown, Figure 5 is a schematic structural diagram of a fourth embodiment of the adapter plate 24 provided by the embodiments of the present application. A bending portion 246 is provided between the electrode terminal welding portion 244 and the adjacent tab welding portion 241. The bending portion 246 is bent from the tab welding portion 241 toward the side of the electrode assembly 23, and the electrode terminal welding portion 244 is connected to the adjacent tab welding portion 241 through the bending portion 246.

[0092] In the embodiments of the present application, a bending portion 246 is provided between the electrode terminal welding portion 244 and the adjacent tab welding portion 241. The bending portion 246 bends from the tab welding portion 241 towards the electrode assembly 23 side, so that a gap is left between the electrode terminal welding portion 244 and the end cap 21, thereby reserving more space for the placement of the electrode terminal 21a. For example, the size of the electrode terminal 21a can be further increased, thereby increasing the current-carrying capacity of the electrode terminal 21a, which is beneficial to improving the fast charging performance of the battery cell 20.

[0093] In some embodiments, please refer to Figure 6 and Figure 7 , Figure 7 FIG. is a schematic structural diagram of the adapter plate from another angle provided by the embodiment of the present application. The electrode terminal welding area 244a includes a protruding portion 244b protruding towards the electrode terminal 21a, and the protruding portion 244b is electrically connected to the electrode terminal 21a.

[0094] In the embodiments of the present application, by adopting the above technical solution, on the one hand, the setting of the protruding portion 244b can quickly align with the electrode terminal 21a through visual recognition or mechanical positioning, improving the automation degree and assembly efficiency of the production line; on the other hand, the setting of the protruding portion 244b also significantly increases the contact area between the electrode terminal welding area 244a and the electrode terminal 21a, thereby reducing the contact resistance between the two, which is beneficial to reducing the energy loss during current conduction, and thus beneficial to improving the fast charging performance of the battery cell 20.

[0095] In some embodiments, please refer to Figure 3 , a hollow area 247 is provided in the included angle area of the adjacent sides of the adapter plate 24.

[0096] In the embodiments of the present application, since the battery cell 20 usually includes two adapter plates 24, that is, a positive adapter plate and a negative adapter plate, by providing the hollow areas 247 in the corresponding included angle areas of the positive and negative adapter plates, an anti-fooling function can be achieved. For example, the hollow area 247 of the positive adapter plate is located in the lower left corner area, and the hollow area 247 of the negative adapter plate is located in the lower right corner area. Thus, the positive and negative adapter plates can be quickly distinguished on the production line, reducing human operation errors, which is beneficial to improving production efficiency and assembly accuracy.

[0097] In the second aspect of the present application, a battery device 100 is provided, including the battery cell 20 provided in the first aspect. The battery device 100 provided by the embodiment of the present application, since it includes the battery cell 20 provided in the first aspect, at least has the same advantages as the battery cell 20 provided in the first aspect.

[0098] The third aspect of the present application provides an electric device 1000, comprising the battery device 100 provided in the second aspect. The electric device 1000 provided in the embodiment of the present application, because it also comprises the battery cell 20 provided in the first aspect, has at least the same advantages as the battery cell 20 provided in the first aspect.

[0099] In addition, the battery cell 20 , the battery device 100 , and the electric equipment 1000 of the present application will be described below with reference to the drawings as appropriate.

[0100] In the embodiment of the present application, the battery cell 20 is the smallest unit constituting the battery device 100. The battery cell 20 includes an electrolyte and a diaphragm. The diaphragm is disposed between the positive electrode and the negative electrode, and mainly plays the role of reducing the probability of short circuit between the positive and negative electrodes, while allowing ions to pass through. During the battery charging and discharging process, the active ions Li + The electrolyte is embedded and released back and forth between the positive electrode and the negative electrode, and plays the role of conducting ions between the positive electrode and the negative electrode.

[0101] The positive electrode sheet includes a positive electrode current collector and a positive electrode film layer disposed on at least one surface of the positive electrode current collector, wherein the positive electrode film layer includes a positive electrode active material composition.

[0102] As an example, the positive electrode current collector has two surfaces opposite to each other in its thickness direction, and the positive electrode film layer is disposed on any one or both of the two opposite surfaces of the positive electrode current collector.

[0103] In some embodiments, the positive electrode current collector may be a metal foil or a composite current collector. For example, aluminum foil may be used as the metal foil. The composite current collector may include a polymer material base and a metal layer formed on at least one surface of the polymer material base. The composite current collector may be formed by forming a metal material (aluminum, aluminum alloy, nickel, nickel alloy, titanium, titanium alloy, silver and silver alloy, etc.) on a polymer material substrate (such as a substrate of polypropylene (PP), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polystyrene (PS), polyethylene (PE), etc.).

[0104] In some embodiments, the positive electrode film layer may further optionally include a binder. As an example, the binder may include one or more of polyvinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE), vinylidene fluoride-tetrafluoroethylene-propylene terpolymer, vinylidene fluoride-hexafluoropropylene-tetrafluoroethylene terpolymer, tetrafluoroethylene-hexafluoropropylene copolymer, and fluorine-containing acrylate resin.

[0105] In some embodiments, the positive electrode film layer may further include a conductive agent, for example, the conductive agent may include at least one of superconducting carbon, acetylene black, carbon black, Ketjen black, carbon dots, carbon nanotubes, graphene and carbon nanofibers.

[0106] In some embodiments, the positive electrode sheet can be prepared in the following manner: the components for preparing the positive electrode sheet, such as the positive electrode active material, the conductive agent, the binder, and any other components, are dispersed in a solvent (such as N-methylpyrrolidone) to form a positive electrode slurry; the positive electrode slurry is coated on the positive electrode current collector, and after processes such as drying and cold pressing, the positive electrode sheet can be obtained.

[0107] The negative electrode sheet includes a negative electrode current collector and a negative electrode film layer provided on at least one surface of the negative electrode current collector, and the negative electrode film layer includes a negative electrode active material.

[0108] As an example, the negative electrode current collector has two surfaces opposite to each other in its own thickness direction, and the negative electrode film layer is provided on any one or both of the two opposite surfaces of the negative electrode current collector.

[0109] In some embodiments, the negative electrode current collector can be a metal foil or a composite current collector. For example, as the metal foil, copper foil can be used. The composite current collector can include a polymer material base layer and a metal layer formed on at least one surface of the polymer material substrate. The composite current collector can be formed by forming a metal material (such as copper, copper alloy, nickel, nickel alloy, titanium, titanium alloy, silver, and silver alloy, etc.) on a polymer material substrate (such as a substrate of polypropylene (PP), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polystyrene (PS), polyethylene (PE), etc.).

[0110] In some embodiments, the negative electrode film layer may also optionally include a binder. The binder can be selected from at least one of styrene-butadiene rubber (SBR), polyacrylic acid (PAA), sodium polyacrylate (PAAS), polyacrylamide (PAM), polyvinyl alcohol (PVA), sodium alginate (SA), polymethacrylic acid (PMAA), and carboxymethyl chitosan (CMCS).

[0111] In some embodiments, the negative electrode film layer may also optionally include a conductive agent. The conductive agent can be selected from at least one of superconducting carbon, acetylene black, carbon black, Ketjen black, carbon dots, carbon nanotubes, graphene, and carbon nanofibers.

[0112] In some embodiments, the negative electrode film layer may also optionally include other additives, such as a thickening agent (such as sodium carboxymethyl cellulose (CMC-Na)), etc.

[0113] In some embodiments, the negative electrode sheet can be prepared in the following manner: the components for preparing the negative electrode sheet, such as the negative electrode active material, the conductive agent, the binder, and any other components, are dispersed in a solvent (such as deionized water) to form a negative electrode slurry; the negative electrode slurry is coated on the negative electrode current collector, and after processes such as drying and cold pressing, the negative electrode sheet can be obtained.

[0114] The electrolyte plays a role in conducting ions between the positive electrode plate and the negative electrode plate. There is no specific limitation on the type of the electrolyte in this application, and it can be selected according to requirements.

[0115] In some embodiments, the electrolyte includes an electrolyte salt and a solvent.

[0116] In some embodiments, the electrolyte salt can be selected from at least one of lithium hexafluorophosphate, lithium tetrafluoroborate, lithium perchlorate, lithium hexafluoroarsenate, lithium bis(fluorosulfonyl)imide, lithium bis(trifluoromethanesulfonyl)imide, lithium trifluoromethanesulfonate, lithium difluorophosphate, lithium difluoro(oxalato)borate, lithium bis(oxalato)borate, lithium difluoro bis(oxalato)phosphate, and lithium tetrafluoro(oxalato)phosphate.

[0117] In some embodiments, the solvent can be selected from at least one of ethylene carbonate, propylene carbonate, ethyl methyl carbonate, diethyl carbonate, dimethyl carbonate, dipropyl carbonate, methyl propyl carbonate, ethyl propyl carbonate, butylene carbonate, fluoroethylene carbonate, methyl formate, methyl acetate, ethyl acetate, propyl acetate, methyl propionate, ethyl propionate, propyl propionate, methyl butyrate, ethyl butyrate, 1,4-butyrolactone, sulfolane, dimethyl sulfone, methyl ethyl sulfone, and diethyl sulfone.

[0118] In some embodiments, the electrolyte may optionally further include additives. For example, the additives can include negative electrode film-forming additives, positive electrode film-forming additives, and can also include additives that can improve certain battery performances, such as additives for improving the overcharge performance of the battery, additives for improving the high-temperature or low-temperature performance of the battery, etc.

[0119] In some embodiments, the battery cell 20 includes a separator. There is no particular limitation on the type of the separator in this application, and any well-known porous structure separator with good chemical stability and mechanical stability can be selected.

[0120] In some embodiments, the material of the separator can be selected from at least one of glass fiber, non-woven fabric, polyethylene, polypropylene, and polyvinylidene fluoride. 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.

[0121] In some embodiments, the positive electrode plate, the negative electrode plate, and the separator can be made into the electrode assembly 23 by a winding process or a stacking process.

[0122] In some embodiments, as Figure 1 shown, the battery cell 20 may include a housing 22. The outer package can be used to encapsulate the above-mentioned electrode assembly 23 and the electrolyte. The outer package includes an end cap 21, a housing 22, and other functional components.

[0123] The end cap 21 refers to a component that covers the opening of the housing 22 to isolate the internal environment of the battery cell 20 from the external environment. Without limitation, the shape of the end cap 21 can be adapted to the shape of the housing 22 to fit the housing 22. Optionally, the end cap 21 can be made of a material with a certain hardness and strength (such as aluminum alloy). In this way, the end cap 21 is not easily deformed when subjected to extrusion and collision, enabling the battery cell 20 to have higher structural strength and improved stability. Functional components such as electrode terminals 21a can be provided on the end cap 21. The electrode terminal 21a can be used for electrical connection with the electrode assembly 23 to output or input the electrical energy of the battery cell 20. In some embodiments, a pressure relief mechanism for discharging the internal pressure when the internal pressure or temperature of the battery cell 20 reaches a threshold can also be provided on the end cap 21. The material of the end cap 21 can also be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc. In some embodiments, an insulating member (not shown in the figure) can also be provided on the inner side of the end cap 21. The insulating member can be used to isolate the electrical connection components in the housing 22 from the end cap 21 to reduce the risk of short circuit. Exemplarily, the insulating member can be plastic, rubber, etc.

[0124] The housing 22 is a component used to cooperate with the end cap 21 to form the internal environment of the battery cell 20. Among them, the formed internal environment can be used to accommodate the electrode assembly 23, electrolyte, and other components. The housing 22 and the end cap 21 can be independent components. An opening can be provided on the housing 22, and the end cap 21 is covered on the opening to form the internal environment of the battery cell 20. Without limitation, the end cap 21 and the housing 22 can also be integrated. Specifically, the end cap 21 and the housing 22 can first form a common connection surface before other components are put into the housing. When it is necessary to encapsulate the inside of the housing 22, the end cap 21 is then covered on 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 electrode assembly 23. The material of the housing 22 can be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc.

[0125] One or more electrode assemblies 23 can be included in the housing 22. The portions of the positive electrode plate and the negative electrode plate without active material respectively constitute the electrode tabs 23a. The positive electrode tab and the negative electrode tab can be located at one end of the main body together or at both ends of the main body respectively. During the charge and discharge process of the battery, the positive active material and the negative active material react with the electrolyte, and the electrode tabs 23a are connected to the electrode terminals to form a current loop.

[0126] Please refer to Figure 8, the battery device 100 includes a box body 10 and battery cells 20, and the battery cells 20 are accommodated in the box body 10. Among them, the box body 10 is used to provide an accommodation space for the battery cells 20, and the box body 10 can adopt various structures. In some embodiments, the box body 10 may include a first part 11 and a second part 12, the first part 11 and the second part 12 cover each other, and the first part 11 and the second part 12 jointly define an accommodation space for accommodating the battery cells 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. The first part 11 covers the open side of the second part 12 so that the first part 11 and the second part 12 jointly define an accommodation space; the first part 11 and the second part 12 may also both be hollow structures with one side open, and the open side of the first part 11 covers the open side of the second part 12. Of course, the box body 10 formed by the first part 11 and the second part 12 can be of various shapes, such as a cylinder, a cuboid, etc.

[0127] In the battery device 100, there may be multiple battery cells 20, and the multiple battery cells 20 can be connected in series, in parallel, or in a mixed connection. A mixed connection means that there are both series and parallel connections among the multiple battery cells 20. The multiple battery cells 20 can be directly connected in series, in parallel, or in a mixed connection together, and then the whole formed by the multiple battery cells 20 is accommodated in the box body 10; of course, the battery device 100 can also be that multiple battery cells 20 are first connected in series, in parallel, or in a mixed connection to form a battery module form, and then multiple battery modules are connected in series, in parallel, or in a mixed connection to form a whole and are accommodated in the box body 10. The battery device 100 may further include other structures. For example, the battery device 100 may further include a busbar component for realizing the electrical connection among the multiple battery cells 20.

[0128] The battery device 100 in the embodiment of the present application includes battery cells 20. In other embodiments, the battery device 100 may further include any one or several of lithium-sulfur batteries, sodium-ion batteries, and magnesium-ion batteries, but is not limited thereto. The battery cells 20 can be in the shape of a cylinder, a flat body, a cuboid, or other shapes, etc.

[0129] In some embodiments, the battery device 100 can be assembled into a battery module. The number of batteries included in the battery module can be one or more, and those skilled in the art can select the specific number according to the application and capacity of the battery module.

[0130] In addition, the present application further provides an electrical device 1000, which includes at least one of the battery cell 20 and / or the battery device 100 provided by the present application. The battery cell 20 or the battery device 100 can be used as the power source of the electrical device 1000, or can be used as the energy storage unit of the electrical device 1000. The electrical device 1000 can include mobile devices (such as mobile phones, laptops, etc.), electric vehicles (such as pure electric vehicles, hybrid electric vehicles, plug-in hybrid electric vehicles, electric bicycles, electric scooters, electric golf carts, electric trucks, etc.), electric trains, ships, satellites, energy storage systems, etc., but is not limited thereto.

[0131] As Figure 9 shown, the electrical device 1000 is a vehicle such as a pure electric vehicle, a hybrid electric vehicle or a plug-in hybrid electric vehicle. Specifically, a partial structural schematic diagram of the electrical device in an embodiment is provided. A battery device 100 is disposed inside the electrical device 1000, and the battery device 100 can be disposed at the bottom, head or tail of the electrical device 1000. The battery device 100 can be used for power supply of the electrical device 1000. For example, the battery device 100 can be used as the operating power source of the electrical device 1000. The electrical device 1000 may further 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, it is used for the working power requirements during the start, navigation and driving of the electrical device 1000.

[0132] In some embodiments of the present application, the battery device 100 can not only be used as the operating power source of the electrical device 1000, but also be used as the driving power source of the electrical device 1000, replacing or partially replacing fuel or natural gas to provide driving power for the electrical device 1000.

[0133] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application, and they should all be covered by the scope of the claims and the description of the present application. In particular, as long as there is no structural conflict, the technical features mentioned in each embodiment can be combined in any way. The present 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 in that: include: case; An end cap, wherein the end cap is provided with an electrode terminal; An electrode assembly, the electrode assembly is accommodated in the shell, and the electrode assembly includes at least three groups of electrode lugs stacked in layers; An adapter plate, wherein the adapter plate is electrically connected to at least three groups of stacked pole lug portions and the electrode terminals; wherein the adapter plate includes a plurality of pole lug welding portions in a first direction, the first direction being the length direction of the battery cell, and a pole lug welding area is provided on one side surface of the pole lug welding portion.

2. The battery cell according to claim 1, characterized in that: The tab welding portion includes two corresponding tab welding areas in a second direction, and the second direction is a width direction of the battery cell.

3. The battery cell according to claim 1, characterized in that: The area of ​​the tab welding area accounts for 40% to 60% of the surface of one side of the tab welding portion.

4. The battery cell according to claim 1, characterized in that: The adapter plate includes at least one connecting portion, and the connecting portion is used to connect adjacent electrode tab welding portions.

5. The battery cell according to claim 4, characterized in that: The end cover is provided with at least one positioning portion, the adapter plate is provided with at least one positioning area, and the positioning portion and the positioning area are provided in a one-to-one correspondence.

6. The battery cell according to claim 5, characterized in that: The positioning area is arranged on the connecting portion.

7. The battery cell according to claim 6, characterized in that: The positioning area is a first notch structure formed by the edge of the connecting portion being recessed inward.

8. The battery cell according to claim 4, characterized in that: The connection portion is further provided with a protection hole, and the protection hole is located between adjacent electrode tab welding portions. When the current flowing through the adapter sheet is greater than a preset threshold, the connection portion is thermally melted.

9. The battery cell according to claim 1, characterized in that: An electrode terminal welding portion is formed at one end of the adapter sheet, the electrode terminal welding portion is connected to the adjacent tab welding portion, and an electrode terminal welding area is formed on one side surface of the electrode terminal welding portion.

10. The battery cell according to claim 9, characterized in that: The end cover is provided with a liquid injection hole, the battery cell includes two adapter plates, one end of one of the adapter plates away from the electrode terminal welding area is provided with a avoidance area, and the avoidance area is arranged corresponding to the liquid injection hole.

11. The battery cell according to claim 10, characterized in that: The avoidance area is a second notch structure formed by the inward depression of the edge of the adapter plate.

12. The battery cell according to claim 9, characterized in that: A bending portion is provided between the electrode terminal welding portion and the adjacent pole tab welding portion. The bending portion is bent from the pole tab welding portion toward one side of the electrode assembly. The electrode terminal welding portion is connected to the adjacent pole tab welding portion through the bending portion.

13. The battery cell according to claim 9, characterized in that: The electrode terminal welding area includes a protruding portion protruding toward one side of the electrode terminal, and the protruding portion is electrically connected to the electrode terminal.

14. The battery cell according to claim 1, characterized in that: A hollow area is provided in the angled area between the adjacent sides of the adapter plate.

15. A battery device, characterized in that: The invention comprises a battery cell as claimed in any one of claims 1 to 14.

16. An electrical equipment, characterized in that: Comprising the battery device as claimed in claim 15.

Images