Battery and electric equipment

Abstract

The utility model discloses a battery and electric equipment, the battery comprises an adapter and a battery cell, the battery cell comprises a body and a plurality of foil tabs, the plurality of foil tabs are arranged on at least one side of the body along the length direction, the plurality of foil tabs are laminated, the plurality of foil tabs form a tab group through ultrasonic welding, and the tab group is arranged on the body along the length direction. The tab group is arranged on the body so as to form a welding area on the tab group, the welding area comprises a first super-welding area and a second super-welding area, the first super-welding area and the second super-welding area are arranged at an interval along the width direction of the body, the first super-welding area is welded with the adapter, and the second super-welding area is not welded with the adapter. The edge of one side of the tab group along the length direction of the body is cut to form a cutting surface, the cutting track of the cutting surface extends from one end of the tab group to the other end of the tab group along the width direction of the body, and the cutting track passes through the first super-welding area and the second super-welding area. According to the battery and the electric equipment, the risk that the diaphragm is punctured by the tab in the battery production process can be reduced.

Description

Technical Field

[0001] The present application relates to the technical field of battery manufacturing, and in particular to a battery and electrical equipment. Background Art

[0002] During the production process of batteries, cells are usually formed by stacking or winding multiple layers of battery cell pole sheets. Part of the foil pole ears that are not coated with active materials will be reserved on the end faces or sides of the battery cells for welding with adapters. In order to accommodate the assembly space inside the battery casing, the foil pole ears are usually cut. However, since the foil pole ears are stacked by multiple layers of pole sheets, it is easy to cause the edges of the pole ears to warp during the production process, and more burrs and / or obvious molten beads will be formed on the cut end faces of the foil pole ears, which can easily cause the risk of puncturing the diaphragm and cause a short circuit in the battery. Utility Model Content

[0003] The embodiments of the present application disclose a battery and an electrical device, which can solve the problem of warping of the edge of the pole ear and the formation of obvious burrs and / or melt beads on the cut surface, thereby reducing the risk of the pole ear piercing the diaphragm during the battery production process.

[0004] In order to achieve the above objectives, in a first aspect, an embodiment of the present application discloses a battery, comprising:

[0005] Adapter;

[0006] A battery cell, the battery cell comprising a body and a plurality of foil tabs, the plurality of foil tabs being arranged on at least one side of the body along the length direction, the plurality of foil tabs being stacked, the plurality of foil tabs being formed into a tab group by ultrasonic welding to form a welding area on the tab group, the welding area comprising a first super welding area and a second super welding area, the second super welding area and the first super welding area being arranged at intervals along the width direction of the body, the first super welding area being welded to the adapter, and the second super welding area being not welded to the adapter;

[0007] The edge of the tab group on one side along the length direction of the body is cut to form a cutting surface, and the cutting track of the cutting surface extends from one end of the tab group to the other end of the tab group along the width direction of the body, and the cutting track passes through the first super welding area and the second super welding area.

[0008] Multiple foil tabs are ultrasonically welded together to form a tab group. Two ultrasonic welding areas are formed at the edge on one side of the tab group. The first ultrasonic welding area is welded to a transfer member to provide overcurrent for the battery cell, and the second ultrasonic welding area integrates multiple foil tabs together. Since multiple stacked foil tabs are integrated, the cutting of the tab group passes through the first ultrasonic welding area and the second ultrasonic welding area, which can not only avoid the edges of the tabs from warping up, but also effectively control the burrs and / or the bead specifications on the cut surface of the tab group, thereby reducing the risk of edge warping, burrs and / or beads piercing the separator during the subsequent tab shaping process.

[0009] As an alternative embodiment, in the embodiment of the first aspect of the present application, the length of the burrs formed on the cut surface and / or the outer diameter of the beads is less than 200 microns.

[0010] By the cutting trajectory passing through the first ultrasonic welding area and the second ultrasonic welding area, the length of the burrs and / or the outer diameter of the beads formed at the cutting edge can be controlled within 200 microns, so that the edges of the cut tab group along the length direction of the body can meet the requirements, facilitating the reduction of the influence of burrs and / or beads during the tab shaping process.

[0011] As an alternative embodiment, in the embodiment of the first aspect of the present application, along the width direction of the body, the distance from the first ultrasonic welding area to the edge of one end of the tab group is T1, and the distance from the second ultrasonic welding area to the edge of the other end of the tab group is T2, and T1 = T2.

[0012] Both the first ultrasonic welding area and the second ultrasonic welding area have a margin area at the edge of the tab group. In this way, both the first ultrasonic welding area and the second ultrasonic welding area have a larger range, so that the battery cell has a larger overcurrent area after the first ultrasonic welding area is welded to the transfer member, enhancing the overcurrent capacity, and enabling multiple foil tabs to have a larger integration area, improving the stability of the integrated tab group. In addition, by defining that the distances from the first ultrasonic welding area and the second ultrasonic welding area to the edge of the tab group are equal respectively, it is beneficial to the uniformity and consistency of pressing multiple foil tabs together, making the integrated tab group more evenly stressed, and facilitating the bending of the tab group with smaller bending deflection, thereby improving the positioning accuracy of the transfer member welding.

[0013] As an alternative embodiment, in the embodiment of the first aspect of the present application, along the width direction of the body, the length of the first ultrasonic welding area is L1, the length of the second ultrasonic welding area is L2, and L1 = L2. The ratio of T1 to L1 is 1:15 - 25;

[0014] The interval between the first ultrasonic welding area and the second ultrasonic welding area is T3, and the ratio of T1 to T3 is 1:1 - 3.

[0015] By controlling the proportional range of the first overwelding area, the second overwelding area to the edge of the tab group, and the interval between the first overwelding area and the second overwelding area, the formation positions of the first overwelding area and the second overwelding area on the tab group can be controlled, so that the functions of the first overwelding area and the second overwelding area in terms of overcurrent of the battery cell and integration can be maximized.

[0016] As an optional implementation manner, in the embodiment of the first aspect of the present application, the first overwelding area and the second overwelding area are symmetrically arranged with respect to the midline in the length direction of the body.

[0017] The first overwelding area and the second overwelding area are symmetrically distributed, that is, the first overwelding area and the second overwelding area are not only equal in the length direction, but also equal in the width direction, and their areas are the same. In this way, during the formation of the first overwelding area and the second overwelding area respectively, there is no need to replace the welding head, and the same welding head can be used to complete two weld marks, which is beneficial to the universality of welding and the improvement of welding efficiency.

[0018] As an optional implementation manner, in the embodiment of the first aspect of the present application, the first overwelding area and the second overwelding area are both strip-shaped areas, and the first overwelding area and the second overwelding area both extend along the width direction of the body.

[0019] The length direction of the overwelding area is consistent with the width direction of the body. When cutting the tab group, more complete first overwelding area and second overwelding area can be retained, so that the welding area is larger, and the tightness of the integrated tab group is higher. This is not only beneficial to the bending and shaping of the tab group, but also beneficial to the overcurrent capacity and integration effect of the battery cell.

[0020] As an optional implementation manner, in the embodiment of the first aspect of the present application, the battery further includes a housing and a top cover, the battery cell is disposed in the housing, and the battery cell is electrically connected to the top cover through the adapter.

[0021] The housing is used to accommodate the battery cell, and the top cover is used to cover the opening of the battery housing, so as to protect the battery cell. And, the connection between the battery cell and the top cover is realized by using the adapter, thereby realizing the conduction of the battery cell and enhancing the overcurrent capacity.

[0022] As an optional implementation manner, in the embodiment of the first aspect of the present application, there are two battery cells, and the two battery cells are stacked along the thickness direction of the battery cell. The tab groups of each battery cell are aligned by bending, and the first overwelding areas of the two battery cells are both welded to the adapter.

[0023] The tab groups of the same polarity of two battery cells are formed on the side of the battery cell by bending. On the premise that the first and second over-welding areas are set to make the tab group cut more flatly, it is more conducive to core alignment, making the shaping effect of the battery cell better, and thus more conducive to the welding of the adapter.

[0024] As an alternative implementation manner, in the embodiment of the first aspect of the present application, the foil tab is a full tab.

[0025] Adopting the design of full tabs can enable the tab group to be connected to the components on the battery cover over the entire area, which can significantly reduce the internal resistance and heat generation of the battery, thereby improving the output power and safety of the battery. Compared with the traditional battery cell designs, such as single-tab and double-tab designs, this structure has higher efficiency and better performance.

[0026] As an alternative implementation manner, in the embodiment of the first aspect of the present application, two tab groups are provided. The polarities of the two tab groups are opposite. The two tab groups are arranged at intervals along the width direction of the body on one side of the body, or the two tab groups are arranged on both sides of the body along the length direction of the body.

[0027] When the two tab groups are arranged at intervals along the width direction of the body on one side of the body, the positive tab group and the negative tab group are located on the same side of the body, and the shape of the tab group is rectangular. At this time, the width direction of the rectangle is smaller than the width direction of the body. When the two tab groups are arranged on both sides of the body along the length direction of the body, that is, the positive tab group and the negative tab group are respectively located on both sides of the body, the shape of the tab group is also rectangular. At this time, the length direction of the tab group is consistent with the width direction of the body, and the length direction of the tab group is generally consistent with the width direction of the body. In this setting mode, the complexity of the battery cell manufacturing process can be reduced, the process can be further simplified, the internal resistance of the battery can be greatly reduced, the large-rate charge and discharge capacity can be realized, and the energy density of the battery can also be increased.

[0028] In a second aspect, the present application also discloses an electrical device, including the battery as described in the first aspect above, and the battery is used to provide electrical energy.

[0029] Compared with the prior art, the beneficial effects of the present application are:

[0030] The present application provides a battery and an electrical device. The battery includes an adapter and a battery cell. The battery cell includes a body and a plurality of foil tabs. The plurality of foil tabs are disposed on at least one side of the body along the length direction. The plurality of foil tabs are stacked, and the plurality of foil tabs are ultrasonically welded to form a tab group, so as to form a welding area on the tab group. The welding area includes a first over-welding area and a second over-welding area. The first over-welding area and the second over-welding area are spaced along the width direction of the body. The first over-welding area is welded to the adapter, and the second over-welding area is not welded to the adapter. The edge of one side of the tab group along the length direction of the body is formed into a cut surface by cutting. The cutting trajectory of the cut surface extends from one end of the tab group to the other end along the width direction of the body, and the cutting trajectory passes through the first over-welding area and the second over-welding area. In the battery of the present application, a plurality of foil tabs are ultrasonically welded together to form a tab group. Two over-welding areas are formed on the edge of one side of the tab group. The first over-welding area is welded to the adapter to play an over-current role for the battery cell. The second over-welding area integrates the plurality of foil tabs. Since the plurality of stacked foil tabs are integrated and the cutting of the tab group passes through the first over-welding area and the second over-welding area, it is possible to not only avoid the warping of the tab edge, but also effectively control the burrs and / or molten beads on the cut surface of the tab group, thereby reducing the risk of warping, burrs and / or molten beads piercing the separator during the subsequent tab shaping process. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings required in the embodiments. Obviously, the 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 drawings can be obtained based on these drawings.

[0032] Figure 1 It is a schematic structural diagram of the positive electrode sheet, negative electrode sheet and separator layer of the battery cell disclosed in the present application;

[0033] Figure 2 It is a schematic structural diagram of the battery disclosed in the present application;

[0034] Figure 3 It is a schematic structural diagram of the battery cell disclosed in the present application;

[0035] Figure 4 It is a top view schematic diagram of the battery cell disclosed in the present application;

[0036] Figure 5 It is a top view schematic diagram of the cut battery cell disclosed in the present application;

[0037] Figure 6 It is a schematic structural diagram of the battery cell formed by winding disclosed in the present application;

[0038] Figure 7 Schematic diagram of the internal structure of the battery disclosed in this application;

[0039] Figure 8 Schematic diagram of the structure of the electrical equipment when it is an electric vehicle disclosed in this application.

[0040] Description of the reference numerals in the drawings:

[0041] 100. Battery; 10. Adapter; 20. Battery cell; 21. Body; 211. Positive electrode plate; 2111. Positive electrode substrate; 2111a. Positive electrode empty foil area; 2112. Positive electrode active coating; 2112a. Positive electrode active material area; 212. Negative electrode plate; 2121. Negative electrode substrate; 2121a. Negative electrode empty foil area; 2122. Negative electrode active coating; 2122a. Negative electrode active material area; 213. Separator layer; 22. Tab group; 22a. Foil tab; 221. Welding area; 2211. First super-welding area; 2212. Second super-welding area; 222. Cut surface; 222a. Cutting track; 30. Housing; 40. Top cover; 200. Electrical equipment; 201. Vehicle body; X. Length direction of the body; Y. Width direction of the body. Detailed implementation manners

[0042] Next, the technical solutions in the embodiments of the present application will be clearly and completely described in conjunction with the 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. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present application.

[0043] In the present application, the orientation or positional relationship indicated by terms such as "upper", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings. These terms are mainly used to better describe the present application and its embodiments, and are not used to limit that the indicated device, element or component must have a specific orientation, or be constructed and operated in a specific orientation.

[0044] Moreover, in addition to being able to represent the orientation or positional relationship, some of the above terms may also be used to represent other meanings. For example, the term "upper" may also be used to represent a certain attachment relationship or connection relationship in some cases. For those of ordinary skill in the art, the specific meanings of these terms in the present application can be understood according to the specific circumstances.

[0045] In addition, the terms "arranged", "provided with", and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral structure; it can be a mechanical connection or an electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, or there can be internal communication between two devices, components, or parts. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0046] In addition, terms such as "first", "second", etc. are mainly used to distinguish different devices, components, or parts (the specific types and structures may be the same or different), and are not used to indicate or imply the relative importance and quantity of the indicated devices, components, or parts. Unless otherwise specified, the meaning of "a plurality" is two or more.

[0047] The technical solutions of this application will be further described below in conjunction with embodiments and the accompanying drawings.

[0048] Refer to Figure 1 and Figure 2 , an embodiment of this application discloses a battery 100, which includes an adapter 10 and a battery cell 20. Among them, the adapter 10 can play a role in overcurrent protection for the battery cell 20. In the embodiment of this application, as Figure 1 shown, the battery cell 20 can be a wound battery cell 20 formed by winding a positive electrode sheet 211, a negative electrode sheet 212, and a separator layer 213 located between the positive electrode sheet 211 and the negative electrode sheet, or can be a stacked battery cell 20 formed by sequentially cross-stacking the positive electrode sheet 211, the separator layer 213, and the negative electrode sheet 212. It can be understood that the battery cell 20 can be a square battery cell or a cylindrical battery cell.

[0049] Among them, the positive electrode sheet 211 can include a positive electrode substrate 2111 (which can be called a positive current collector) and a positive electrode active coating 2112. The positive electrode active coating 2112 can be coated on the front and back of the positive electrode substrate 2111. The positive electrode substrate 2111 can be aluminum foil. The material of the positive electrode active coating 2112 can be made of one or more of lithium cobaltate, lithium manganate, lithium iron phosphate, and lithium nickel cobalt manganate (also known as ternary material). The embodiment of this application does not limit the material of the positive electrode active coating 2112, and the specific forming method is a publicly known technology in the art, and will not be elaborated here.

[0050] The negative electrode sheet 212 may include a negative electrode substrate 2121 (which may be referred to as a negative current collector) and a negative electrode active coating 2122. The negative electrode active coating 2122 may be coated on the front and back surfaces of the negative electrode substrate 2121. The negative electrode substrate 2121 may be a copper foil. The negative electrode active coating 2122 is made by mixing a negative electrode active material (carbon material or non-carbon material) with a binder and an additive. For example, it may be a carbon negative electrode material, an alloy-based negative electrode material, a tin-based negative electrode material, a lithium-containing transition metal nitride negative electrode material, a nanoscale material, a nano negative electrode material, etc. The embodiments of the present application do not limit the material of the negative electrode active coating 2122, and the specific forming method is a publicly known technology in the art and will not be elaborated here.

[0051] In some possible implementation manners, continue to refer to Figure 2 , the battery 100 may further include a housing 30 and a top cover 40. The battery cell 20 is disposed in the housing 30, and the battery cell 20 is electrically connected to the top cover 40 through an adapter 10. The housing 30 is used to accommodate the battery cell 20 and plays a role in protecting the battery cell 20. The top cover 40 may be used to seal the opening of the housing 30 of the battery 100, and the connection between the battery cell 20 and the top cover 40 is realized by using the adapter 10. Specifically, one end of the adapter 10 is welded to the tab group 22 of the battery cell 20, and the other end is welded to the terminal of the battery 100, so that the top cover 40 is connected to the battery cell 20 for electrical conduction, thereby realizing the electrical conduction of the battery cell 20 and enhancing the overcurrent capacity.

[0052] Optionally, the housing 30 may be a soft packaging material, such as an aluminum plastic film, which may be composed of a nylon layer, an aluminum layer, and a plastic material layer. The battery cell 20 is encapsulated in the housing 30 through an encapsulation process to form a soft-pack battery 100. However, it is not limited thereto. The housing 30 may also be made of plastic or metal. The plastic material and the metal material may have a certain hardness. Encapsulating the battery cell 20 in the housing 30 may form a cylindrical battery 100 or a square battery 100, which can resist external impacts to achieve the purpose of protecting the battery 100.

[0053] In some embodiments, refer to Figure 3 and Figure 4, the battery cell 20 may include a body 21 and a plurality of foil tabs 22a. The plurality of foil tabs 22a are disposed on at least one side of the body 21 along the length direction. The plurality of foil tabs 22a are stacked. The plurality of foil tabs 22a are ultrasonically welded to form a tab group 22, so as to form a welding area 221 on the tab group 22. The welding area 221 includes a first overweld zone 2211 and a second overweld zone 2212. The first overweld zone 2211 and the second overweld zone 2212 are spaced apart along the width direction Y of the body. The first overweld zone 2211 is welded to the adapter 10, and the second overweld zone 2212 is not welded to the adapter. An edge of one side of the tab group 22 along the length direction X of the body 21 is formed into a cut surface 222 by cutting. The cutting trajectory 222a of the cut surface 222 extends from one end of the tab group 22 to the other end along the width direction Y of the body, and the cutting trajectory 222a passes through the first overweld zone 2211 and the second overweld zone 2212.

[0054] In the battery of the present application, a plurality of foil tabs 22a are overwelded together by ultrasonic welding to form a tab group 22. Two overweld zones are formed at the edge of one side of the tab group 22. The first overweld zone 2211 is welded to the adapter 10 to play a current-carrying role for the battery cell 20, and the second overweld zone 2212 integrates the plurality of foil tabs 22a. Since the plurality of stacked foil tabs 22a are integrated, the cutting of the tab group 22 passes through the first overweld zone 2211 and the second overweld zone 2212, which can not only avoid the warping of the tab edge, but also effectively control the burrs and / or bead specifications of the cut surface 222 of the tab group 22, thereby reducing the risk of warping, burrs and / or beads piercing the separator during the subsequent tab shaping process.

[0055] In addition, there will be a temperature rise during the further welding of the first overweld zone 2211 to the adapter 10, and the temperature even reaches above 100°C. Since the second overweld zone 2212 is spaced from the first overweld zone 2211, a large temperature gradient can be formed on the heat dissipation path of the tab group 22, which plays a role in rapid heat dissipation, thereby avoiding the situation that the temperature generated during welding scalds the separator.

[0056] The cutting trajectory 222a of the above-mentioned cutting plane 222 is parallel to the width direction Y of the body 21 of the battery cell 20, so that the cutting edges of the first over-welding area 2211 and the second over-welding area 2212 are on the same straight line. On the one hand, it is beneficial for the bending and alignment of the tab group 22 in subsequent processes; on the other hand, before welding the adapter 10 to the first over-welding area 2211, it is necessary to detect the first over-welding area 2211 through a CCD (Charge-Coupled Device). Taking this flat cutting edge as the positioning reference can ensure the accuracy of the maximum range of CCD edge grasping, which is beneficial to the accuracy of the welding of the adapter 10, and thus can ensure that the adapter 10 and the battery cell 20 have the maximum over-current area.

[0057] It can be understood that when different cutting methods are used, the defects caused to the cutting plane 222 of the tab group 22 may be different. For example, when using a cutting tool, more burrs may be formed on the cutting plane 222 of the tab group 22, and there is a risk of piercing the separator. When using a laser cutting method, obvious molten beads may be formed on the cutting plane 222 of the tab group 22, and the falling of the molten beads also has a risk of piercing the separator.

[0058] In some possible embodiments, the length of the burrs formed on the cutting plane 222 and / or the outer diameter of the molten beads is less than 200 microns, such as a few microns, more than ten microns or dozens of microns, etc. By passing the cutting trajectory 222a through the first over-welding area 2211 and the second over-welding area 2212, the length of the burrs formed on the cutting edge and / or the outer diameter of the molten beads can be controlled within 200 microns, so that the edge of the tab group 22 along the length direction X of the body 21 can meet the requirements, so as to reduce the influence of burrs and / or molten beads during the shaping process of the tab group 22.

[0059] In some possible embodiments, along the width direction Y of the body 21, the distance from the first over-welding area 2211 to the edge of one end of the tab group 22 is T1, and the distance from the second over-welding area 2212 to the edge of the other end of the tab group 22 is T2, and T1 = T2. That is, both the first over-welding area 2211 and the second over-welding area 2212 have a margin area at the edge of the tab group 22. In this way, both the first over-welding area 2211 and the second over-welding area 2212 can have a larger range, so that after the first over-welding area 2211 is welded to the adapter 10, the battery cell 20 has a larger over-current area, enhancing the over-current capacity, and enabling the plurality of foil tabs 22a to have a larger integration area, improving the stability of the integrated tab group 22. In addition, by limiting that the distances from the first over-welding area 2211 and the second over-welding area 2212 to the edge of the tab group 22 are equal respectively, it is beneficial to the uniformity and consistency of pressing the plurality of foil tabs 22a together, making the integrated tab group 22 more evenly stressed, and being beneficial to the bending of the tab group 22 with smaller bending deflection, so as to improve the positioning accuracy of the welding of the adapter 10.

[0060] In some possible implementations, see Figure 4 , along the width direction Y of the body 21, the length of the first super weld zone 2211 is L1, the length of the second super weld zone 2212 is L2, L1=L2, the ratio of T1 to L1 is 1:15-25, the interval between the first super weld zone 2211 and the second super weld zone 2212 is T3, and the ratio of T1 to T3 is 1:1-3. For example, the ratio of T1 to L1 can be 1:18, 1:20, 1:22, etc., and the ratio of T1 to T3 can be 1:1, 1:2, etc. By controlling the ratio range of the first super weld zone 2211, the second super weld zone 2212 to the edge of the tab group 22 and the interval between the first super weld zone 2211 and the second super weld zone 2212, the formation positions of the first super weld zone 2211 and the second super weld zone 2212 on the tab group 22 can be controlled, so that the first super weld zone 2211 and the second super weld zone 2212 can play the role of current flow and integration of the battery cell 20 to the maximum extent.

[0061] Preferably, the ratio of T1 to L1 can be 1:20, and the ratio of T1 to T3 can be 1:2, so that the ratio between T1, L1, T3, L2 and T2 can be 1:20:2:20:1, and this ratio will not make the space occupied by the super welding area too large, which is not conducive to heat dissipation, nor will it make the space occupied by the super welding area too small, affecting the flow capacity and integration effect of the battery cell 20. Under this ratio, the distribution of the first super welding area 2211 and the second super welding area 2212 is reasonable, which can not only effectively ensure that the multiple foil tabs 22a are not easy to disperse after integration, but also facilitate the subsequent welding with the adapter 10, and ensure the flow capacity of the battery cell 20.

[0062] Optionally, see Figure 4 and Figure 5 The width of the original tab group 22 along the length direction X of the body 21 can be W1, and the width of the tab group 22 after cutting along the length direction X of the body 21 can be W2, wherein the ratio between W1 and W2 can be 4:1, and the cutting track 222a can pass through the first super welding area 2211 and the second super welding area 2212. On the basis of controlling the cutting ratio, the range of the retained first super welding area 2211 and the second super welding area 2212 is appropriate, which is convenient for the integration of the first super welding area 2211 and the transfer welding and the tab group 22, and also convenient for the bending of the tab group 22.

[0063] In some possible embodiments, the first overweld area 2211 and the second overweld area 2212 are symmetrically arranged with respect to the midline of the body 21 in the length direction. The first overweld area 2211 and the second overweld area 2212 are symmetrically distributed, that is, the first overweld area 2211 and the second overweld area 2212 are not only equal in the length direction but also equal in the width direction, and their areas are the same. In this way, in the process of forming the first overweld area 2211 and the second overweld area 2212 respectively, there is no need to replace the welding head, and the same welding head can be used to complete two weld marks, which is beneficial to the versatility of welding and improves the welding efficiency.

[0064] In some possible embodiments, both the first overweld area 2211 and the second overweld area 2212 are strip-shaped regions, and both the first overweld area 2211 and the second overweld area 2212 extend along the width direction of the body 21. That is, the length direction of the overweld area is consistent with the width direction Y of the body 21. When trimming the tab group 22, more complete first overweld area 2211 and second overweld area 2212 can be retained, so that the welding area 221 is larger, and thus the tightness of the integrated tab group 22 is higher. This is not only beneficial to the bending and shaping of the tab group 22 but also beneficial to the current-carrying capacity and integration effect of the battery cell 20.

[0065] Of course, in some other embodiments, the shapes of the first overweld area 2211 and the second overweld area 2212 can also be, but are not limited to, rectangles, arcs, polygons, etc., as long as the current-carrying capacity required by the battery cell 20 and sufficient integration effect are satisfied.

[0066] In some possible embodiments, two tab groups 22 are provided, and the polarities of the two tab groups 22 are opposite. The two tab groups 22 are arranged at intervals along the width direction Y of the body 21 on one side of the body 21, or the two tab groups 22 are arranged on both sides of the body 21 along the length direction X of the body 21. One of the tab groups 22 can be a positive tab group 22, and the other tab group 22 can be a negative tab group 22. When the two tab groups 22 are arranged at intervals along the width direction Y of the body 21 on one side of the body 21, the positive tab group 22 and the negative tab group 22 are located on the same side of the body 21, and the shape of the tab group 22 is rectangular. At this time, the width direction of the rectangle is smaller than the width direction Y of the body 21. When the two tab groups 22 are arranged on both sides of the body 21 along the length direction X of the body 21, that is, the positive tab group 22 and the negative tab group 22 are respectively located on both sides of the body 21, the shape of the tab group 22 is also rectangular. At this time, the length direction of the tab group 22 is consistent with the width direction Y of the body 21, and the length direction of the tab group 22 is generally consistent with the width direction Y of the body 21. In this setting mode, the complexity of the manufacturing process of the battery cell 20 can be reduced, the process can be further simplified, the internal resistance of the battery 100 can be greatly reduced, the large-rate charge and discharge capacity can be realized, and the energy density of the battery 100 can also be increased.

[0067] In one example, the foil tab 22a can be designed as a bipolar tab. In this case, the two tab groups 22 can be arranged at intervals along the width direction Y of the body 21 on one side of the body 21. This form of bipolar tab can be formed by die-cutting the positive and negative electrode substrates 2121 without coated active materials and then winding or laminating them.

[0068] Of course, in another example, the foil tab 22a can be a full tab. In this case, the two tab groups 22 can be arranged on both sides of the body 21 along the length direction X of the body 21. During the formation of this full tab form, the positive and negative electrode substrates without coated active materials do not need to be die-cut. The positive and negative electrode substrates 2121 (positive and negative current collectors) are directly used as tabs. By connecting with the components on the top cover 40 of the battery 100 over the entire area, the internal resistance and heat generation of the battery 100 can be significantly reduced, thereby improving the output power and safety of the battery 100. This structure has higher efficiency and better performance compared to traditional cell 20 designs, such as single-tab and bipolar-tab designs.

[0069] In the embodiment of the present application, the wound full-tab cell 20 is taken as an example for illustration. The arrangement of the positive electrode sheet 211, the negative electrode sheet 212, and the separator layer 213 is as Figure 6 shown. The positive electrode sheet 211 is formed with a positive electrode active material region 2112a and a positive electrode empty foil region 2111a. The positive electrode empty foil region 2111a can be arranged adjacent to the positive electrode active material region 2112a. The positive electrode empty foil region 2111a is the region of the positive electrode substrate 2111 without coated positive active material. The negative electrode sheet 212 is formed with a negative electrode active material region 2122a and a negative electrode empty foil region 2121a. The negative electrode empty foil region 2121a can be arranged adjacent to the negative electrode active material region 2122a. The negative electrode empty foil region 2121a is the region of the negative electrode substrate 2121 without coated negative active material. It can be understood that the positive electrode empty foil region 2111a and the negative electrode empty foil region 2121a form foil tabs 22a with opposite polarities through winding.

[0070] Optionally, referring to Figure 7 , the cell 20 can include two cells. The two cells 20 are stacked along the thickness direction of the cell 20. The tab groups 22 of each cell 20 are aligned by bending. The first over-welding regions of the two cells 20 are both welded to the adapter 10. That is, the tab groups 22 with the same polarity of the two cells 20 are formed on the side of the cell 20 by bending, and the two cells are welded to the top cover 40 through the adapter 10. As can be seen from the foregoing embodiments, on the premise that the tab groups 22 are cut more smoothly in the two over-welding regions, it is more conducive to core alignment, making the shaping effect of the cell 20 better, and thus more conducive to the welding of the adapter 10.

[0071] Of course, in some embodiments, the battery 100 may further include a protection board (not shown), which may be disposed in the housing 30 and connected to the tab group 22. The protection board may be a circuit board that protects the battery 100 and can be used to monitor the voltage, current, insulation status, state of charge, etc. in the battery cell 20, thereby playing a role in protecting the battery 100.

[0072] The present application also provides an electrical device 200, which includes the battery 100 in the above embodiments, and the battery 100 is used to provide electrical energy. The electrical device 200 of the present application may include, but is not limited to, electronic devices, drones, backup power supplies, electric vehicles, power tools, large household batteries, etc. Refer to Figure 8 , taking the electrical device 200 as an electric vehicle as an example, the electrical device may include a vehicle body 201 and a battery 100, and the battery 100 is disposed in the vehicle body 201.

[0073] The battery and the electrical device disclosed in the embodiments of the present application have been introduced in detail above. Specific examples are used in this article to elaborate on the principle and implementation manner of the present application. The description of the above embodiments is only used to help understand the battery and the electrical device of the present application and its core idea; at the same time, for those of ordinary skill in the art, according to the idea of the present application, there will be changes in the specific implementation manner and application scope. In summary, the content of this specification should not be construed as a limitation to the present application.

Claims

1. A battery, characterized in that: include: Adapter; A battery cell, the battery cell comprising a body and a plurality of foil tabs, the plurality of foil tabs being arranged on at least one side of the body along the length direction, the plurality of foil tabs being stacked, the plurality of foil tabs being ultrasonically welded to form a tab group to form a welding area on the tab group, the welding area comprising a first super welding area and a second super welding area, the first super welding area and the second super welding area being spaced apart along the width direction of the body, the first super welding area being welded to the adapter, and the second super welding area being not welded to the adapter; The edge of the tab group on one side along the length direction of the body is cut to form a cutting surface, and the cutting track of the cutting surface extends from one end of the tab group to the other end of the tab group along the width direction of the body, and the cutting track passes through the first super welding area and the second super welding area.

2. The battery according to claim 1, characterized in that The length of the burrs formed on the cutting surface and / or the outer diameter of the molten beads are less than 200 micrometers.

3. The battery according to claim 1, characterized in that Along the width direction of the body, the distance from the first super welding area to the edge of one end of the tab group is T1, and the distance from the second super welding area to the edge of the other end of the tab group is T2, and T1=T2.

4. The battery according to claim 3, characterized in that Along the width direction of the body, the length of the first super welding zone is L1, the length of the second super welding zone is L2, L1=L2, and the ratio of T1 to L1 is 1:15-25; The interval between the first super welding area and the second super welding area is T3, and the ratio of T1 to T3 is 1:1-3.

5. The battery according to claim 4, characterized in that The first super welding area and the second super welding area are symmetrically arranged relative to a midline of the body along a length direction.

6. The battery according to claim 1, characterized in that The first super welding area and the second super welding area are both strip-shaped areas, and the first super welding area and the second super welding area both extend in a direction along the width of the body.

7. The battery according to claim 1, characterized in that The battery further comprises a shell and a top cover, the battery core is arranged in the shell, and the battery core is electrically connected to the top cover through the adapter.

8. The battery according to claim 7, characterized in that The battery cells include two, the two battery cells are stacked along the thickness direction of the battery cells, the tab groups of each battery cell are aligned by bending, and the first super welding areas of the two battery cells are welded to the adapter.

9. The battery according to any one of claims 1 to 8, characterized in that: The foil tab is a full tab.

10. The battery according to any one of claims 1 to 8, characterized in that: There are two tab groups with opposite polarities, and the two tab groups are spaced apart on one side of the body along the width direction of the body, or the two tab groups are arranged on both sides of the body along the length direction of the body.

11. An electrical device, characterized in that: The invention comprises a battery as claimed in any one of claims 1 to 10, wherein the battery is used to provide electrical energy.

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