Battery and electronic device

Abstract

To provide a battery and an electronic apparatus capable of preventing laser irradiation to an electrode assembly, avoiding damage of the electrode assembly, and securing yield of a product when an outer case of the battery is sealed and welded.SOLUTION: An outer housing and a cover plate, wherein a portion of the cover plate adjacent to an edge protrudes toward an inner space of the outer housing to form a boss, a side of the boss away from the inner space of the outer housing comprises a groove, a portion of the cover plate located radially outside the boss forms a connecting edge, the boss is embedded in the opening, and the connecting edge overlaps with an end portion of the outer housing; Further, a welding mark formed by welding is provided between the connecting edge and the end portion of the outer housing, a cross-sectional size of the welding mark gradually decreases from a radial outer side to a radial inner side of the cover plate, an inner wall of the groove includes a bottom wall and an outer groove wall surrounding an outer periphery of the bottom wall, and a connecting portion between the bottom wall and the outer groove wall is provided with a punched groove formed by punching.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to the technical field of batteries, and in particular to batteries and electronic devices. [Background technology]

[0002] 2. Description of the Related Art With the development of social economy, more and more electrical devices, such as new energy vehicles, communication base stations, energy storage containers, etc., adopt batteries as energy storage and supply devices.

[0003] Currently, in some battery models, when the outer casing is sealed by laser welding, a boss punched into the edge of the cover plate leaves a gap between the side wall and the outer casing. This causes the incident laser to reflect within the gap and reach the electrode assembly inside the outer casing, damaging the electrode assembly and causing problems with product quality. Summary of the Invention [Problem to be solved by the invention]

[0004] In view of the above problems, the present invention provides a battery and an electronic device that can prevent laser irradiation to the electrode assembly when sealing and welding the outer case of the battery, avoid damage to the electrode assembly, and ensure product yield. [Means for solving the problem]

[0005] the connecting edge of the cover plate forms a connecting edge, the boss is embedded in the opening, and the connecting edge overlaps an edge of the outer case. The connecting edge and the edge of the outer case have weld marks formed by welding between them, and the cross-sectional size of the weld marks gradually decreases from the radially outer side to the radially inner side of the cover plate, the cross section being determined by the central axis of the cover plate and an arbitrary radial line. The inner wall of the groove includes a bottom wall and an outer groove wall surrounding the outer periphery of the bottom wall. The connecting portion of the bottom wall and the outer groove wall has a stamped groove formed by stamping.

[0006] In some embodiments, the outer groove wall includes a straight wall portion extending along the thickness of the cover plate, and an outermost end of the stamped groove does not extend beyond the straight wall portion in the radial direction of the cover plate.

[0007] In some embodiments, the stamped groove has a groove cross section cut along a reference plane, the reference plane being defined by the central axis of the cover plate and any radial line, and the groove cross section having a symmetrical structure at any radial side of the cover plate relative to the central axis.

[0008] In some embodiments, the punched groove has a groove cross-section cut along a reference plane, the reference plane being determined by the central axis of the cover plate and any radial line, the groove cross-section having an asymmetric structure at any radial side of the cover plate from the central axis, and the deepest part of the punched groove being located on one side closer to the outer groove wall than the center line L of the width direction of the groove cross-section of the punched groove.

[0009] In some embodiments, the height H1 of the boss on the cover plate is in the range of 0.8 mm≦H1≦5 mm; and / or the depth H2 of the groove in the thickness direction of the cover plate is in the range of 0.1 mm≦H2≦4.5 mm; and / or the depth H3 of the stamped groove in the thickness direction of the cover plate is in the range of 0.05 mm≦H3≦0.4 mm; and / or the outer surface of the boss includes a linear extension that fits tightly to the inner wall of the outer case, and the height H4 of the linear extension in the thickness direction of the cover plate is in the range of H4≧0.1 mm; and / or the relationship between the width W1 of the stamped groove and the width W2 of the groove in the radial direction of the cover plate satisfies 0.05≦W1 / W2≦0.2; and / or the connecting portion between the outer surface and the bottom surface of the boss further includes an outer chamfer, and the radius R1 of the outer chamfer is in the range of 0.1 mm≦R1≦1.2 mm.

[0010] In some embodiments, the battery further includes an electrode assembly disposed within the exterior case and having a tab on one end facing the cover plate, wherein a welding area is provided on the bottom wall other than the stamped groove, and the cover plate is electrically connected to the tab via the welding area.

[0011] In some embodiments, the battery further includes a current collector plate disposed between the cover plate and the tab, welded to the welding region of the cover plate and the tab, respectively, and against which the boss abuts.

[0012] In some embodiments, a minimum distance T between the stamped groove and the welded area along the radial direction of the cover plate satisfies 0.2 mm≦T≦1 mm.

[0013] In some embodiments, the cover plate has a hardness of 100 HV or greater.

[0014] A second aspect of the present invention provides an electronic device comprising the battery according to the first aspect of the present invention. [Effects of the Invention]

[0015] According to the battery of the present invention, a boss is provided on the edge of the cover plate, and the boss is embedded in the opening of the outer casing. The boss has a connecting edge along its radial outer side that is tightly welded to the end face of the outer casing. A groove is provided on one side of the boss away from the electrode assembly, and a stamping groove is provided in the groove. During the formation of the stamping groove, the pressure generated by the stamping presses the metal at the connection between the bottom wall and the outer groove wall of the groove and causes it to flow toward the outer surface of the boss. This reduces the chamfered portion on one side of the boss facing the inner wall of the outer casing and lengthens the linear extension portion of the outer surface of the boss, resulting in better adhesion between the outer surface of the boss and the inner wall of the outer casing, and allowing the boss to better block lasers. In this way, when a laser welding device is used to weld the gap between the connecting edge and the end face of the outer case, after the laser enters the inside of the outer case, it is possible to prevent the laser from being reflected within the gap between the outer surface of the boss and the inner wall of the outer case, and to prevent the laser from being irradiated onto the electrode assembly and damaging the electrode assembly, thereby improving the welding quality of the battery and ensuring product yield. [Brief explanation of the drawings]

[0016] In order to more clearly describe the embodiments of the present invention or the technical solutions in the prior art, the drawings necessary for use in the description of the embodiments or the prior art are briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technical personnel in this field, other drawings can be obtained based on these drawings without any creative work.

[0017] [Figure 1] 1 is a structural schematic diagram of a battery in some embodiments of the present invention. [Figure 2] FIG. 2 is a cross-sectional view taken along the groove cross section AA in FIG. [Figure 3] FIG. 3 is an enlarged view of the circled portion B in FIG. 2. [Figure 4]1 is a schematic diagram of the flow of cover plate material during the formation of the stamped grooves in some embodiments of the present invention. [Figure 5] 10A-10C are schematic diagrams illustrating the flow of cover plate material during the formation of stamped grooves in some other embodiments of the present invention. [Figure 6] 1 is a partial structural schematic diagram of a battery according to some embodiments of the present invention. [Figure 7] 1 is a structural schematic diagram of an electrode assembly in some embodiments of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0018] In order to make the above-mentioned objectives, features and advantages of the embodiments of the present invention clearer and easier to understand, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings of the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments, not all of the embodiments of the present invention. All other embodiments obtained by ordinary skilled in the art based on the embodiments of the present invention without creative work shall fall within the scope of protection of the present invention.

[0019] With the development of society and the economy, an increasing number of electrical devices, such as new energy vehicles, communication base stations, and energy storage containers, are adopting batteries as energy storage and supply devices. Currently, some battery models employ a stamping process to form a boss on the edge of the cover plate, which is then embedded into the outer casing, and then laser welding is used to seal the outer casing. However, for steel-shell batteries and other batteries with high shell strength, the cover plate's high strength makes it difficult to form during the stamping process, and the stamped boss often results in a large chamfer on the side wall used to mate with the outer casing. As the chamfer becomes larger, the linear portion of the boss side wall becomes shorter or even disappears, resulting in a certain gap between the boss side wall and the outer casing. Thus, when welding the mating seam between the cover plate and the outer casing, the incident laser is likely to reflect within the gap and reach the electrode assembly inside the outer casing, damaging the electrode assembly and causing product quality problems.

[0020] In view of this, the present embodiment provides a battery 100, which may be a primary battery or a secondary battery. A primary battery refers to a battery that cannot be recharged after discharge, while a secondary battery refers to a battery that can be reused by recharging after discharge to reactivate the active material. The battery may be a lithium-ion battery, a sodium-ion battery, a sodium-lithium-ion battery, a lithium metal battery, a sodium metal battery, a lithium-sulfur battery, a magnesium-ion battery, a nickel-cadmium battery, or the like, but the present embodiment is not limited thereto.

[0021] 1 and 2, specifically, the battery 100 of this embodiment may include an outer case 1, a cover plate 2, and an electrode assembly 3. Here, an opening is provided at one end of the outer case 1, and the interior space of the outer case 1 functions as an accommodating cavity for the electrode assembly 3. For example, if the battery 100 is a cylindrical battery, the outer case 1 may be cylindrical with an opening at the top or bottom end, and the inside of the outer case 1 defines a cylindrical accommodating cavity. The cover plate 2 can cover and close the opening of the outer case 1.

[0022] 3 , the electrode assembly 3 is disposed within the interior space of the outer case 1, and a tab 31 is provided on one end of the electrode assembly 3 facing the cover plate 2, and the tab 31 is electrically connected to the cover plate 2. For example, the cover plate 2 may be a negative electrode cover plate, and the tab 31 may be a negative electrode tab. The electrical connection may be achieved by directly welding the negative electrode cover plate and the negative electrode tab, or the electrical connection may be achieved between the negative electrode cover plate and the negative electrode tab via an intermediate adapter, such as a current collector 4. In this case, both the negative electrode cover plate 2 and the negative electrode tab are welded to the current collector 4.

[0023] 2, the outer case 1 further includes a side wall 11 and a top wall 12, the side wall 11 surrounding the top wall 12, and the top wall 12 is located at one end opposite the opening in the side wall 11. The battery 100 further includes a positive current collector 5 and a pole 6. The pole 6 penetrates the top wall. A positive electrode tab 323 is provided at one end of the electrode assembly 3 facing the pole 6, and the positive current collector 5 is disposed between the pole 6 and the electrode assembly 3, and is welded to the pole 6 and the positive electrode tab 323 of the electrode assembly 3, respectively. In this case, the current collector 4 can function as a negative current collector for the battery 100, and a tab 31 at one end of the electrode assembly 3 facing the cover plate 2 functions as a negative electrode tab for the electrode assembly 3.

[0024] 7 , the electrode assembly 3 may include a positive electrode sheet 32, a negative electrode sheet 33, and a separator 34. Here, the positive electrode sheet 32 ​​includes a positive electrode fluid collector 321 and a positive electrode active coating layer 322 coated on the surface of the positive electrode fluid collector 321. The negative electrode sheet 33 includes a negative electrode fluid collector 331 and a negative electrode active coating layer 332 coated on the surface of the negative electrode fluid collector 331. For example, if the battery 100 is a cylindrical battery 100, the positive electrode sheet 32, the separator 34, and the negative electrode sheet 33 are stacked in this order and wound to form a wound electrode assembly 3.

[0025] Of course, in other possible embodiments, the battery 100 may be a prismatic shell battery. In this case, the positive electrode sheet 32, the separator 34, and the negative electrode sheet 33 may be stacked in order and wound to form a wound electrode assembly 3. Alternatively, the positive electrode sheet 32, the separator 34, and the negative electrode sheet 33 may all have a multi-layer structure, and the positive electrode sheet 32 ​​and the negative electrode sheet 33 may be alternately stacked and separated by the separator 34 to form a stacked electrode assembly 3.

[0026] Referring to FIG. 3 , a portion of the cover plate 2 adjacent to its edge protrudes toward the interior space of the outer case 1 to form a boss 21, and one side of the boss 21 facing away from the interior space of the outer case 1 includes a groove 22. For example, the boss 21 may be formed by punching the edge of the cover plate 2. During the punching process, the boss 21 is formed on the inner surface of the cover plate 2 (i.e., the surface facing the receiving cavity), and the groove 22 is formed on the side of the boss 21 facing away from the receiving cavity (i.e., the outer surface of the cover plate 2). Furthermore, a portion of the cover plate 2 radially outward of the boss 21 forms a connecting edge 24. When the boss 21 is inserted into the opening, the connecting edge 24 overlaps with the edge of the outer case 1 and is then welded to the end face of the outer case 1. For example, the welding method may be laser welding, ultrasonic welding, or the like. At this time, a weld mark 25 is formed between the connecting edge 24 and the end face of the outer case 1. The cross-sectional size of the weld mark 25 gradually decreases from the radially outer side to the radially inner side of the cover plate 2. Here, the cross section may be determined by the central axis of the cover plate 2 and an arbitrary radial line, such as the AA cross section shown in Figures 1 and 2.

[0027] In combination with FIG. 3 , it should be noted that in this embodiment, the laser welding device performs laser seam welding from the side of the outer case 1 along the radial direction of the cover plate 2 toward the seam between the connecting edge 24 and the end face of the outer case 1 (as indicated by the arrow of the weld mark 25 in FIG. 3 ), forming the weld mark 25. Furthermore, during the welding process, the laser welding device may be held and fixed in position, and only the battery 100 may be rotated for welding. When laser welding the connecting edge 24 and the outer case 1, the cross-sectional size, such as the cross-sectional width, of the weld mark 25 gradually decreases along the laser transmission direction and away from the welding device. In this embodiment, the weld mark 25 is formed between the connecting edge 24 and the end face of the outer case 1, and the cross-sectional size of the weld mark 25 gradually decreases from the radially outer side of the cover plate 2 toward the radially inner side. Welding the mating seam between the connecting edge 24 and the outer case 1 using laser seam welding can more effectively close the gap, and the process is more mature and reliable, ensuring welding quality.

[0028] 3, the inner wall of the groove 22 includes a bottom wall 222 and an outer groove wall 223 surrounding the outer periphery of the bottom wall 222. Here, a stamped groove 23 is provided at the connection portion of the bottom wall 222 and the outer groove wall 223, i.e., the stamped groove 23 is formed on the inner chamfer 221 at the connection portion of the bottom wall 222 and the outer groove wall 223. Optionally, the stamped groove 23 and the groove 22 may be formed simultaneously in the same stamping process.

[0029] It should be noted that when the punched groove 23 is not provided and the cover plate 2 is punched to form the boss 21, the outer chamfered portion 211 at the intersection between the outer surface 210 of the boss 21 (facing the outer groove wall 223 of the groove 22) and the bottom surface (facing the bottom wall 222 of the groove 22) is relatively large, and the linear extension portion 212 of the outer surface of the boss 21 (this linear extension portion 212 is the portion where the outer surface 210 of the boss 21 contacts the outer case 1, and this portion extends along the axial direction of the cover plate 2) is relatively short, so there is a certain gap between the outer surface 210 of the boss 21 and the inner wall of the outer case 1. When welding the connecting edge 24 and the end face of the outer casing 1 to form the weld mark 25, the laser irradiated from the laser welding device toward the gap between the connecting edge 24 and the end face of the outer casing 1 is likely to be reflected by the gap between the outer surface 210 of the boss 21 and the inner wall of the outer casing 1 after entering the receiving cavity, and may ultimately be reflected back to the electrode assembly 3, damaging the electrode assembly 3. In this embodiment, a punching groove 23 is provided at the connection portion between the bottom wall 222 and the outer groove wall 223 of the groove 22. In the process of forming the punching groove 23, the punching device presses the inner wall of the groove 22, causing the material at the connection portion between the bottom wall 222 and the outer groove wall 223 to flow and deform toward one side of the outer casing 1, thereby reducing the outer chamfer 211 of the boss 21 and lengthening the linear extension 212 of the outer surface 210 of the boss 21, resulting in a more preferable contact between the outer surface 210 of the boss 21 and the inner wall of the outer casing 1. In this way, even if a laser enters the inside of the outer case 1 through the gap between the connecting edge 24 and the end face of the outer case 1, the boss 21 can block the laser, preventing the laser from being reflected by the electrode assembly 3 and damaging the electrode assembly 3.

[0030] According to the battery 100 of the embodiment of the present invention, a boss 21 is provided on the edge of the cover plate 2, the boss 21 is embedded in the opening of the outer case 1, and a connecting edge 24 is provided on the radially outer side of the boss 21 that is tightly welded to the end face of the outer case 1; a boss 21 is provided on the edge of the cover plate 2, the boss 21 is embedded in the opening of the outer case 1, and a connecting edge 24 is provided on the radially outer side of the boss 21 that is tightly welded to the end face of the outer case 1; a groove 22 is provided on one side of the boss 21 away from the electrode assembly 3, and a punched groove 23 formed by punching is provided at the connection portion between the bottom wall 222 of the groove 22 and the outer groove wall 223. During the formation of the punched groove 23, the pressure generated by the punching device causes the metal at the junction between the bottom wall 222 of the groove 22 and the outer groove wall 223 to flow toward the outer surface of the boss, thereby reducing the chamfer on one side of the boss 21 facing the inner wall of the outer casing 1 and lengthening the linear extension 212 of the outer surface 210 of the boss 21. This improves the adhesion between the outer surface 210 of the boss 21 and the inner wall of the outer casing 1, and allows the boss 21 to better block the laser. In this way, when a laser welding device is used to weld the gap between the connecting edge 24 and the end face of the outer casing 1, the laser is prevented from being reflected in the gap between the outer surface 210 of the boss 21 and the inner wall of the outer casing 1 after entering the inside of the outer casing 1, preventing the laser from being irradiated on and damaging the electrode assembly 3. This improves the welding quality of the battery 100 and ensures a high production yield.

[0031] 3 and 4 , in some embodiments, the opening direction of the punched groove 23 is along the axial direction of the cover plate 2, away from the interior space of the outer case 1. The outer groove wall 223 of the groove 22 includes a straight wall portion 2231 extending along the thickness direction of the cover plate 2, and the straight wall portion 2231 and the linear extension portion 212 of the outer surface 210 of the boss 21 face each other and are parallel to each other. In the radial direction of the cover plate 2, the outermost end of the punched groove 23 does not extend beyond the straight wall portion 2231. In this way, by simply providing a protruding structure on the punching device that fits into the punched groove 23, the groove 22 and the punched groove 23 can be simultaneously formed using the punching device. That is, when punching along the thickness direction of the cover plate 2, the protruding structure on the punching device and the outer groove wall 223 of the groove 22 do not interfere with each other in the thickness direction of the cover plate 2. This makes it easier for the punching device to retract from the groove 22 after the punched groove 23 is completed.

[0032] Furthermore, since the opening direction of the groove 22 and the opening direction of the punched groove 23 are substantially the same, the punching device can form the punched groove 23 and the groove 22 by punching only once along the thickness direction of the cover plate 2, making the manufacturing process of the cover plate 2 simpler and more efficient. Of course, two punching processes may be performed, in which the groove 22 is punched first and then the punched groove 23 is punched.

[0033] The punched groove 23 has a groove cross section cut along a reference plane (for example, the AA cross section shown in FIGS. 1 and 2 ), and the reference plane may be determined by the central axis of the cover plate 2 and any radial line. That is, the reference plane passes through the central axis and any radial line of the cover plate 2. Since the punched groove 23 is formed in an annular shape surrounding the cover plate 2, the groove cross section of the punched groove 23 on the reference plane includes two parts, and the two parts are located on both sides of the central axis of the cover plate 2, respectively.

[0034] 3, in this embodiment, the groove cross section has a symmetrical structure on any radial side of the central axis of the cover plate 2. For example, the groove cross section on any radial side of the central axis of the stamped groove 23 of the cover plate 2 may be formed into a V-shape, a U-shape, or other symmetrical structure. In this way, during the stamping process, the cover plate material corresponding to the stamped groove 23 flows uniformly toward the outer periphery, reducing the chamfered portion of the outer surface of the boss 21 and increasing the length of the linear extension portion 212 on the outer surface 210 of the boss 21.

[0035] 4 , the groove cross section may have an asymmetric structure on any one side of the central axis along the radial direction of the cover plate 2, with the deepest portion of the stamped groove 23 being located on one side of the widthwise centerline of the groove cross section, closer to the outer groove wall 223. Here, the width direction of the stamped groove 23 is parallel to the radial direction of the cover plate 2. Thus, compared with solutions in which the stamped groove 23 has a symmetric structure, in this embodiment, when forming the stamped groove 23, the material of the cover plate 2 between the inner chamfer 221 and the outer chamfer 211 can flow and deform mainly toward one side of the outer casing 1, reducing material flow and deformation in other directions. This effectively reduces the outer chamfer 211 of the boss 21 and lengthens the length of the linear extension 212 on the outer surface 210 of the boss 21. This not only improves the forming efficiency of the stamped groove 23 but also ensures a tight fit between the boss 21 and the outer casing 1.

[0036] In some embodiments, referring to FIG. 6 , the range of the height H1 of the boss 21 of the cover plate 2 is 0.8 mm≦H1≦5 mm. Here, the height H1 of the boss 21 of the cover plate 2 may be the sum of the height of the boss 21 and the thickness of the non-boss portion of the cover plate 2. For example, the value of the height H1 of the boss 21 of the cover plate 2 may be 0.8 mm, 1 mm, 1.5 mm, 2 mm, 2.5 mm, 3.5 mm, 4 mm, 4.5 mm, or 5 mm. Of course, the present invention is not limited thereto, and the height H1 of the boss 21 of the cover plate 2 can be reasonably selected within the above range according to actual needs. In this way, on the one hand, if the height of the boss 21 is too small, for example, less than 0.8 mm, the depth at which the boss 21 fits into the outer case 1 may be too small, which may result in the boss 21 being unable to effectively block the laser and prevent the cover plate 2 from forming a stable fit with the outer case 1. On the other hand, if the height of the boss 21 is excessively large, for example, greater than 5 mm, it is possible to prevent the boss 21 from occupying too much of the internal space of the outer case 1, which would be detrimental to improving the utilization rate of the internal space and the energy density of the battery 100.

[0037] 6 , in some embodiments, the depth H2 of the groove 22 in the thickness direction of the cover plate 2 is in the range of 0.1 mm≦H2≦4.5 mm. For example, the depth H2 of the groove 22 in the thickness direction of the cover plate 2 may be 0.1 mm, 0.2 mm, 0.5 mm, 0.8 mm, 1 mm, 1.5 mm, 2 mm, 2.5 mm, 3 mm, 3.5 mm, 4 mm, or 4.5 mm. Of course, the present invention is not limited thereto, and the depth H2 of the groove 22 in the thickness direction of the cover plate 2 can be reasonably selected within the above range according to actual needs. In this way, on the one hand, if the depth of the groove 22 is too small, for example, less than 0.1 mm, the height of the boss 21 will be too small, which will prevent the boss 21 from effectively blocking the laser and resulting in a stable fit with the outer shell 1. On the other hand, if the depth of the groove 22 is too large, for example, greater than 4.5 mm, it is possible to prevent the boss 21 from occupying too much of the internal space of the outer case 1, which would be detrimental to improving the utilization rate of the internal space and the energy density of the battery 100. It can be seen that the depth of the groove 22 is always smaller than the thickness of the boss 21 of the cover plate 2.

[0038] 6, in some embodiments, the depth H3 of the punched groove 23 in the thickness direction of the cover plate 2 is in the range of 0.05 mm≦H3≦0.4 mm. For example, the depth H3 of the punched groove 23 in the thickness direction of the cover plate 2 may be 0.05 mm, 0.1 mm, 0.15 mm, 0.2 mm, 0.25 mm, 0.3 mm, 0.35 mm, or 0.4 mm. Of course, the present invention is not limited thereto, and the depth H3 of the punched groove 23 in the thickness direction of the cover plate 2 can be reasonably selected within the above range according to actual needs. In this way, on the one hand, if the depth of the punched groove 23 is too small, for example, less than 0.05 mm, during the forming process of the punched groove 23, the pressing force of the cover plate 2 material between the inner chamfer 221 and the outer chamfer 211 will be too small, the outer chamfer 211 of the boss 21 will not be effectively reduced, and the outer surface 210 of the boss 21 will not be able to form an effective fit with the inner wall of the outer case 1, thereby limiting the laser blocking effect of the boss 21. On the other hand, if the depth of the punched groove 23 is too large, for example, more than 0.4 mm, the bottom wall 222 of the recessed groove 22 will be punched out, damaging the cover plate 2 and requiring it to be scrapped. It should be noted that the depth of the punched groove 23 should always be smaller than the wall thickness of the boss 21.

[0039] 6 , in some embodiments, the outer surface 210 of the boss 21 includes a linear extension 212. For example, the portion of the outer surface 210 of the boss 21 other than the outer chamfered portion is formed as the linear extension 212. The height H4 of the linear extension 212 in the thickness direction of the cover plate 2 is in the range of 0.1 mm≦H4≦2 mm. For example, the height H4 of the linear extension 212 in the thickness direction of the cover plate 2 may be 0.1 mm, 0.2 mm, 0.5 mm, 0.8 mm, 1 mm, 1.2 mm, 1.5 mm, or 2 mm. Of course, the present invention is not limited thereto, and the height H4 of the linear extension 212 in the thickness direction of the cover plate 2 can be reasonably selected within the above range according to actual needs. In this way, on the one hand, if the height of the linear extension 212 is too small, for example, less than 0.1 mm, it is possible to prevent the depth at which the boss 21 fits into the outer case 1 from becoming too small, which would be detrimental to favorably blocking the laser at the weld mark 25 between the connecting edge 24 and the end face of the outer case 1. On the other hand, if the height of the linear extension 212 is too large, for example, more than 2 mm, it is possible to prevent the boss 21 from occupying too much of the internal space of the outer case 1, which would be detrimental to improving the utilization rate of the internal space and the energy density of the battery 100.

[0040] 6, in some embodiments, the ratio between the width W1 of the punched groove 23 and the width W2 of the groove 22 in the radial direction of the cover plate 2 satisfies 0.1≦W1 / W2≦1. For example, the ratio of W1 to W2 may be 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, or 1. When the ratio is 1, the width W1 of the punched groove 23 in the radial direction of the cover plate 2 is the same as the width W2 of the groove 22. Of course, the present invention is not limited thereto, and the ratio of W1 to W2 can be reasonably selected within the above range according to actual needs. In this way, the processing device can smoothly extend into the groove 22 to process the punched groove 23, and during the processing of the punched groove 23, the cover plate material in the punched groove 23 can be made to flow favorably toward one side of the outer groove wall 223 of the groove 22, ensuring that the outer chamfer 211 of the boss 21 is small and the length of the linear extension 212 on the outer surface 210 of the boss 21 is long. In this way, when laser seam welding is performed between the connecting edge 24 of the cover plate 2 and the edge of the outer case 1, the boss 21 can more favorably block the laser.

[0041] 6 , in some embodiments, an outer chamfer 211 is further provided at the connection between the outer surface 210 and the bottom surface 213 of the boss 21. The outer chamfer 211 faces the inner chamfer 221, and the radius R1 of the outer chamfer 211 is in the range of 0.1 mm≦R1≦1.2 mm. For example, the radius R1 of the outer chamfer 211 may be 0.1 mm, 1.2 mm, 0.4 mm, 0.5 mm, 0.8 mm, 1 mm, or 1.2 mm. Of course, the present invention is not limited to this, and the radius R1 of the outer chamfer 211 can be reasonably selected within this range according to actual needs. That is, after the stamping groove 23 is formed, the radius of the outer chamfer 211 of the boss 21 facing one side of the outer case 1 is within this range, so that the outer surface 210 of the boss 21 can be properly attached to the inner wall of the outer case 1 and can block laser light.

[0042] In some embodiments, a welding area 224 is provided on the bottom wall 222 of the groove 22 other than the punched groove 23. The welding area 224 is a weld mark formed by welding the cover plate 2 and the battery internal assembly. The cover plate 2 may be electrically connected to the tab 31 through the welding area 224. For example, the welding area 224 and the tab 31 may be directly welded to achieve the electrical connection between the cover plate 2 and the tab 31. Alternatively, the welding area 224 may be electrically connected to the tab 31 via an intermediate adapter such as a current collector plate 4. In this way, there are various methods for connecting the cover plate 2 and the tab 31, and a reasonable selection can be made according to actual needs.

[0043] In one specific example, the battery 100 may further include a current collector 4. The current collector 4 is disposed between the cover plate 2 and the tab 31, and is welded to the welding area 224 of the cover plate 2 and the tab 31, respectively. That is, the cover plate 2 and the tab 31 are temporarily connected via the current collector 4, and the current collector 4 functions as an intermediate adapter between the cover plate 2 and the tab 31. At this time, the boss 21 can abut against the current collector 4. In this way, on the one hand, by using the boss 21 to press the current collector 4, the current collector 4 and the electrode assembly 3 can be fixedly positioned within the outer case 1. On the other hand, because the boss 21 is part of the structure of the cover plate 2 and is a metal part, even if the boss 21 is not electrically connected to the current collector 4 (for example, the central region of the current collector 4 is welded to the cover plate 2 and the boss 21 and the welding area 224 are radially separated), the boss 21 can be used for heat conduction. In some possible embodiments, the boss 21 can be directly welded to the heat collection plate 4 to achieve conduction between the cover plate 2 and the heat collection plate 4. In this case, the boss 2 can achieve both electrical connection and heat conduction.

[0044] When the bottom wall 222 of the groove 22 is welded to the current collecting plate 4 by laser penetration welding, the laser irradiation direction is the same as the thickness direction of the cover plate 2. The laser energy density when the laser is irradiated on the surface of the workpiece is related to the distance from the laser focus to the weld surface. Because the inner wall surface of the punched groove 23 is not a plane perpendicular to the laser, welding within the punched groove 23 results in different distances from the laser focus, resulting in different laser energy densities at different points. This can result in uneven weld depths at different points, potentially preventing an effective connection between the punched groove 23 and the current collecting plate 4. In this embodiment, the welding area 224 is located on a straight portion of the bottom wall 222, avoiding the punched groove 23. This allows the laser energy to be more efficiently concentrated and pass through the cover plate 2 to the current collecting plate 4, ensuring an effective and reliable connection between the boss 21 and the current collecting plate 4.

[0045] 6, in some embodiments, the width W2 of the groove 22 in the radial direction of the cover plate 2 is in the range of 2 mm≦W2≦15 mm. For example, the width W2 of the groove 22 in the radial direction of the cover plate 2 may be 2 mm, 3 mm, 4 mm, 5 mm, 6 mm, 7 mm, 8 mm, 9 mm, 10 mm, 11 mm, 12 mm, 13 mm, 14 mm, or 15 mm. Of course, the present invention is not limited thereto, and the width W2 of the groove 22 in the radial direction of the cover plate 2 can be reasonably selected within the above range according to actual needs. In this way, on the one hand, it is possible to prevent the welding equipment from having difficulty entering the groove 22 for welding operations and the processing equipment from having difficulty entering the groove 22 for processing the punched groove 23 when the width of the groove 22 is too small, for example, less than 2 mm. On the other hand, if the width of the groove 22 is excessively large, for example, greater than 15 mm, the surface area of ​​the cover plate 2 in thermal contact with the module cooling system becomes too small, which can prevent this from being detrimental to the external heat dissipation of the battery 100.

[0046] In some embodiments, combining FIGS. 3 and 6 , the radial width W3 of the cover plate 2 of the welding area 224 is in the range of 0.5 mm≦W3≦13 mm. For example, the radial width W3 of the cover plate 2 of the welding area 224 may be 0.5 mm, 1 mm, 2 mm, 4 mm, 6 mm, 8 mm, 10 mm, 12 mm, or 13 mm. Of course, the present invention is not limited thereto, and the radial width W3 of the cover plate 2 of the welding area 224 can be reasonably selected within the above range according to actual needs. In this way, on the one hand, if the width of the welding area 224 is too small, for example, less than 0.5 mm, the welding area between the boss 21 and the current collecting plate 4 will be too small, which will increase the resistance of the welding point and reduce the current-carrying capacity. On the other hand, if the width of the welding area 224 is too large, for example, more than 13 mm, the welding area will be too large, which will reduce the welding quality.

[0047] In some embodiments, referring to FIG. 3 , the minimum distance T between the punched grooves 23 and the welding areas 224 along the radial direction of the cover plate 2 is 0.2 mm≦T≦1 mm. For example, the minimum distance T between the punched grooves 23 and the welding areas 224 may be 0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, or 1 mm. Of course, the present invention is not limited thereto, and the minimum distance T between the punched grooves 23 and the welding areas 224 can be reasonably selected within the above range according to actual needs. In this way, it is possible to prevent welding heat from being transferred into the punched grooves 23 due to a narrow distance, which could cause welding explosion points. At the same time, it is possible to prevent mutual interference between the punched grooves 23 and the welding areas 224, which also helps relieve stress during the welding process.

[0048] In some embodiments, the hardness of the cover plate 2 is 100 HV or more, thereby ensuring sufficient strength and good pressure resistance of the cover plate 2. For example, the cover plate 2 may be a steel structural member such as a commonly used cold-rolled carbon steel plate or strip (SPCC).

[0049] An electronic device according to an embodiment of the second aspect of the present invention will be described below.

[0050] The electronic device of this embodiment may be a vehicle, a mobile phone, a portable device, a laptop computer, a ship, a spacecraft, an electric toy, a power tool, or the like. The vehicle may be a fuel-powered vehicle, a gas-powered vehicle, or a new energy vehicle. The new energy vehicle may be a pure electric vehicle, a hybrid vehicle, a long-distance vehicle, or the like. The spacecraft may be an airplane, a rocket, a space shuttle, a spaceship, or the like. The electric toys include stationary or mobile electric toys such as game consoles, electric toy cars, electric toy boats, and electric toy airplanes. The electric tools include metal cutting tools, grinding tools, assembly tools, and railroad tools, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete vibrators, and electric planers. The electronic device may be a battery module, a battery pack, or the like. The embodiment of the present invention is not particularly limited to the above electronic devices.

[0051] The electronic device may include a device main body and the battery 100 of the above embodiment. The device main body may include a battery compartment, and the battery 100 is provided in the battery compartment and electrically connected to the device main body. For example, a power interface may be provided in the battery compartment, and the battery 100 may be connected to the power interface.

[0052] By providing the electronic device according to the embodiment of the present invention with the battery 100 according to the embodiment, the welding quality of the battery 100 is improved, which is beneficial for improving the user experience.

[0053] It should be noted that while the embodiments represented by terms such as "one embodiment," "embodiment," "exemplary embodiment," "some embodiments," etc., referred to herein, may include a particular feature, structure, or characteristic, not all embodiments necessarily include the particular feature, structure, or characteristic. Furthermore, such terms do not necessarily refer to the same embodiment. Furthermore, when a particular feature, structure, or characteristic is described in conjunction with an embodiment, it is within the knowledge of one skilled in the art to implement such feature, structure, or characteristic in conjunction with other embodiments, whether or not explicitly described.

[0054] In general, terms should be understood, at least in part, by their usage in the context in which they are used. For example, depending at least in part on the context, the term "one or more" as used herein may be used in the singular sense to describe any feature, structure, or characteristic, or may be used in the plural sense to describe a combination of features, structures, or characteristics. Similarly, terms such as "a," "the," and "said" may be interpreted as referring to the singular or the plural, depending on the context.

[0055] It should be readily understood that "on...", "above..." and "on..." in this disclosure should be interpreted in the broadest sense, and that "on..." not only means "directly on top of something" but also includes the meaning of "on top of something" with an intervening feature or layer, and that "above..." or "on..." not only means "above..." or "on top of..." but can also include the meaning of "above..." or "on..." without an intervening feature or layer (i.e., directly on top of something).

[0056] Also, for convenience of description, spatially relative terms, such as "below," "below," "directly below," "above," "up," etc., may be used to describe the relationship of one element or feature to another, such as the relationship shown in the drawings. The spatially relative terms are intended to encompass various orientations of the device during use or operation in addition to the orientation depicted in the drawings. The device may have other orientations (rotated 90 degrees or at other orientations), and the spatially relative terms used herein should be interpreted accordingly.

[0057] Finally, it should be noted that the above embodiments are used solely to describe the technical solutions of the present application, and are not intended to limit the same. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that the technical solutions described in the above embodiments can be modified, or some or all of the technical features therein can be equivalently replaced. And these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application. [Industrial Applicability]

[0058] The battery and electronic device of the present invention can be applied to the field of battery technology. [Explanation of symbols]

[0059] 1: Outer case 11: Side wall 12: Upper wall 2: Cover plate 21: Boss 210:Outer surface 211: Outer chamfer 212: Linear extension part 213: Bottom 22: Groove 221: Inner chamfer 222: Bottom wall 223: Outer ditch wall 2231: Straight wall section 224: Welding area 23: Punched groove 24: Connecting edge 25: Weld marks 3: Electrode assembly 31: Tab 32: Positive electrode sheet 321: Positive electrode collecting fluid 322: Positive electrode active coating layer 323: Positive electrode tab 33: Negative electrode sheet 331: Negative electrode fluid collector 332: Negative electrode active coating layer 34: separator; 4: Current collector plate 5: Positive current collector plate 6: Extreme 100:Battery H1, H4: Height H2, H3: Depth L: Center line R1: Radius T: Minimum spacing W1, W2, W3: Width

Claims

1. an outer case including an opening; a cover plate for closing the opening, a portion adjacent to an edge of the cover plate protruding toward the interior space of the outer case to form a boss, a recess formed on one side of the boss away from the interior space of the outer case, and a portion of the cover plate positioned radially outward of the boss to form a connecting edge; the boss is embedded in the opening, the connecting edge overlaps an end of the outer case, and a weld mark is formed between the connecting edge and the end of the outer case by welding, the cross-sectional size of the weld mark gradually decreases from the radially outer side to the radially inner side of the cover plate, and the cross-section is determined by a central axis of the cover plate and an arbitrary radial line; The inner wall of the groove includes a bottom wall and an outer groove wall surrounding the outer periphery of the bottom wall, and a punched groove formed by punching is provided at a connection portion between the bottom wall and the outer groove wall. A battery characterized by:

2. the outer groove wall includes a linear wall portion extending along the thickness direction of the cover plate, In the radial direction of the cover plate, the outermost end of the stamped groove does not extend beyond the straight wall portion.

2. The battery of claim 1 .

3. The punched groove has a groove cross section cut along a reference plane, and the reference plane is defined by a central axis of the cover plate and an arbitrary radial line; The groove cross section has a symmetrical structure at any one side along the radial direction of the cover plate with respect to the central axis.

3. The battery according to claim 2 .

4. The punched groove has a groove cross section cut along a reference plane, and the reference plane is defined by a central axis of the cover plate and an arbitrary radial line; the groove cross section has an asymmetric structure at any one side portion of the cover plate along the radial direction of the central axis line, Furthermore, the deepest portion of the punched groove is located on one side closer to the outer groove wall than the center line L in the width direction of the groove cross section of the punched groove.

3. The battery according to claim 2 .

5. The height H1 of the boss of the cover plate is in the range of 0.8 mm≦H1≦5 mm; and / or The depth H2 of the groove in the thickness direction of the cover plate is in the range of 0.1 mm≦H2≦4.5 mm; and / or The depth H3 of the punched groove in the thickness direction of the cover plate is in the range of 0.05 mm≦H3≦0.4 mm; and / or The outer surface of the boss includes a linear extension that contacts the inner wall of the outer case, and the range of the height H4 of the linear extension in the thickness direction of the cover plate is H4≧0.1 mm; and / or In the radial direction of the cover plate, the width W1 of the punched groove and the width W2 of the recessed groove satisfy 0.05≦W1 / W2≦0.2; and / or The connecting portion between the outer surface and the bottom surface of the boss further has an outer chamfer, and the radius R1 of the outer chamfer is in the range of 0.1 mm≦R1≦1.2 mm.

2. The battery of claim 1 .

6. an electrode assembly provided within the outer case and having a tab on one end facing the cover plate; further comprising a welding area is provided on the bottom wall other than the stamped groove, and the cover plate is electrically connected to the tab through the welding area; 2. The battery of claim 1 .

7. a current collecting plate provided between the cover plate and the tab, welded to the welding region of the cover plate and the tab, respectively, and against which the boss abuts; 7. The battery of claim 6, further comprising:

8. A minimum distance T between the punched groove and the welding area along the radial direction of the cover plate satisfies 0.2 mm≦T≦1 mm.

7. The battery according to claim 6.

9. The hardness of the cover plate is 100 HV or more.

2. The battery of claim 1 .

10. An electronic device comprising the battery according to any one of claims 1 to 9.

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