Cover plate assembly, battery and electronic device

Abstract

The utility model provides a cover plate subassembly, battery and electronic device relates to battery technical field, cover plate subassembly includes: cover plate and sealing element, the cover plate has opposite first surface and second surface, the partial structure of first surface faces the second surface one side recess and forms the sealing groove, the sealing element is contained in the sealing groove, the sealing element is contained in the sealing groove. The side wall of the sealing groove comprises a matching section matched with the periphery of the sealing element, the matching section comprises a first chamfer, the bottom wall of the sealing groove is provided with a liquid injection hole for injecting electrolyte into the battery, and the area, corresponding to the first chamfer, of the second surface is provided with a first stamping groove sunken towards one side of the first surface. According to the cover plate assembly, the first stamping groove is formed in the cover plate, after the sealing piece is assembled to the sealing groove, the matching section of the side wall of the sealing groove and the side face of the sealing piece are attached more tightly, the welding effect of the sealing piece and the cover plate can be improved, and therefore the surrounding area of the liquid injection hole is sealed well.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, in particular to a cover plate assembly, a battery and an electronic device. Background Art

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

[0003] At present, for some models of batteries, after injecting electrolyte into the battery through the liquid injection hole on the cover plate, the liquid injection hole and its surrounding area will be sealed. However, due to the influence of the processing technology and the structure of the cover plate itself, there is still a certain problem with the fitting tightness between the cover plate and the seal, resulting in poor sealing performance of the liquid injection hole and its surrounding area. Summary of the Utility Model

[0004] In view of the above problems, the utility model provides a cover plate assembly, a battery and an electronic device, which can achieve good sealing of the area around the liquid injection hole.

[0005] The utility model provides a cover plate assembly for a battery, including: a cover plate and a seal. The cover plate has a first surface and a second surface opposite to each other. A part of the structure of the first surface is recessed towards the second surface to form a sealing groove. The seal is accommodated in the sealing groove. The side wall of the sealing groove includes a fitting section that fits with the outer periphery of the seal. The fitting section includes a first chamfer. The bottom wall of the sealing groove is provided with a liquid injection hole for injecting electrolyte into the battery. The area of the second surface corresponding to the first chamfer is provided with a first stamping groove that is recessed towards the first surface.

[0006] In some embodiments, the stamping direction of the first stamping groove is towards the first chamfer.

[0007] In some embodiments, the first stamping groove has a groove cross-section intercepted along a reference plane. The reference plane is determined by the central axis of the cover plate and any one radial line. The part of the groove cross-section on either side of the central axis along the radial direction of the cover plate is a symmetric structure.

[0008] In some embodiments, the first stamping groove has a groove cross-section intercepted along a reference plane. The reference plane is determined by the central axis of the cover plate and any one radial line. The part of the groove cross-section on either side of the central axis along the radial direction of the cover plate is an asymmetric structure. And the point in the first stamping groove closest to the first surface is located on the side of the center line L1 of the groove cross-section of the first stamping groove in its own width direction close to the liquid injection hole.

[0009] In some embodiments, a partial structure of the first surface is recessed toward the second surface to form a first-level sunk groove, the sealing groove is a second-level sunk groove formed by a partial bottom wall of the first-level sunk groove being recessed toward the second surface, the first chamfer is located at the connection between the bottom wall of the first-level sunk groove and the side wall of the second-level sunk groove, and the first stamping groove is formed at a position on the second surface corresponding to the bottom wall of the first-level sunk groove.

[0010] In some embodiments, the thickness of the bottom wall of the first-level sunk groove is T1, the depth of the first stamping groove in the thickness direction of the cover plate is T2, and T1 and T2 satisfy: 0.8 ≤ T2 / T1 < 1.

[0011] The second aspect of the present utility model further provides a cover plate assembly for a battery, including: a cover plate having opposite first and second surfaces, a partial structure of the first surface being recessed toward the second surface to form a sealing groove, a liquid injection extension portion extending along the axial direction of the cover plate being provided on the bottom wall of the sealing groove, the liquid injection extension portion defining a liquid injection hole; a liquid injection plug detachably provided in the liquid injection hole; a second chamfer being provided at the connection between the inner wall surface of the liquid injection extension portion and the bottom wall of the sealing groove; and a second stamping groove recessed toward the first surface being further provided in a region of the second surface corresponding to the second chamfer.

[0012] In some embodiments, the material extrusion direction of the second stamping groove is toward the second chamfer.

[0013] In some embodiments, the thickness of the bottom wall of the sealing groove is T3, the depth of the second stamping groove in the thickness direction of the cover plate is T4, and T3 and T4 satisfy: 0.8 ≤ T4 / T3 < 1.

[0014] In some embodiments, the cover plate further includes a body portion formed by a portion of the cover plate located radially outside the sealing groove, the thickness of the body portion is T5, the thickness of the bottom wall of the sealing groove is T3, and T5 and T3 satisfy: 0.03 ≤ T3 / T5 ≤ 0.95.

[0015] The second aspect of the present utility model provides a battery, including: a housing defining a receiving cavity with an open end; an electrode assembly provided in the receiving cavity; and the cover plate assembly according to the first aspect of the present utility model, the cover plate assembly sealing the opening.

[0016] The third aspect of the present utility model provides an electronic device, including: the battery according to the second aspect of the present utility model.

[0017] According to the cover plate assembly of the present utility model, a sealing groove is provided on the first surface of the cover plate, a liquid injection hole for liquid injection is provided in the sealing groove, a sealing member is arranged in the sealing groove, and a first stamping groove is provided on the second surface of the cover plate. In this way, by processing the first stamping groove, the stamping equipment can squeeze the cover plate material at the first stamping groove to flow towards the first surface side, making the first chamfer smaller. In this way, after the sealing member is assembled into the sealing groove, the fitting section on the side wall of the sealing groove fits more tightly with the side surface of the sealing member, so as to facilitate welding and sealing of the gap between the fitting section and the side surface of the sealing member by using welding equipment, and prevent problems such as virtual soldering and false soldering, thereby achieving good sealing of the liquid injection hole area and preventing the battery from leaking liquid and short-circuiting. Description of the Drawings

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required to be used in the description of the embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0019] Figure 1 Structural schematic diagram of a battery according to some embodiments of the present utility model;

[0020] Figure 2 Along Figure 1 Cross-sectional view of the A-A section in

[0021] Figure 3 For Figure 2 Enlarged view of the circled part B in

[0022] Figure 4 Partial structural schematic diagram of a battery according to an embodiment of the present utility model;

[0023] Figure 5 Schematic diagram of the welding area of the cover plate and the current collector plate in some embodiments of the present utility model;

[0024] Figure 6 Cross-sectional view of the electrode assembly according to an embodiment of the present utility model.

[0025] Explanation of the reference numerals in the drawings:

[0026] 100 - Battery;

[0027] 1 - Cover plate assembly;

[0028] 11 - Cover plate; 110 - Body part; 111 - Primary sinking groove; 112 - Sealing groove; 113 - Liquid injection extension part; 114 - Liquid injection hole; 115 - First chamfer; 116 - Second chamfer; 117 - First stamping groove; 118 - Second stamping groove; 119 - Fitting section;

[0029] 12 - Seal;

[0030] 2 - Electrode assembly; 21 - Tab; 22 - Positive electrode sheet; 221 - Positive current collector; 222 - Positive active coating; 223 - Positive tab; 23 - Negative electrode sheet; 231 - Negative current collector; 232 - Negative active coating; 24 - Separator;

[0031] 3 - Current collecting plate;

[0032] 4 - Outer shell; 41 - Side wall; 42 - Top wall; D - Welding area; 5 - Positive current collecting plate; 6 - Terminal post. Specific embodiments

[0033] In order to make the above - mentioned objects, features and advantages of the embodiments of the present application more obvious and understandable, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without making creative efforts shall fall within the scope of protection of the present application.

[0034] With the development of social economy, more and more electrical equipment uses batteries as energy storage and supply devices, such as new energy vehicles, communication base stations, energy storage containers, etc. For some current models of batteries, after injecting electrolyte into the battery through the liquid injection hole on the cover plate, the liquid injection hole and its surrounding area will be sealed. However, due to the influence of the processing technology and the structure of the cover plate itself, there are still certain problems with the fitting tightness between the cover plate and the seal, resulting in poor sealing of the liquid injection hole and its surrounding area. For example, for some models of batteries, after injecting electrolyte into the battery through the liquid injection hole on the cover plate, the seal is embedded in the sink around the liquid injection hole, and the seal and the edge of the sink are welded and sealed. However, due to the large gap between the sink and the side of the cover plate, it is easy to cause welding quality problems such as virtual welding and false welding, which is not conducive to the sealing of the liquid injection hole.

[0035] In view of this, this embodiment provides a cover plate assembly 1 for a battery 100.

[0036] Combined with Figure 1 and Figure 2 , the battery 100 may include: an outer shell 4, a cover plate assembly 1, and an electrode assembly 2. Among them, one end of the outer shell 4 is provided with an opening, and the inner cavity of the outer shell 4 serves as an accommodation cavity for the electrode assembly 2. Taking the battery 100 as a cylindrical battery as an example, its outer shell 4 may be in the shape of a cylinder with an opening at the top or bottom. The inner side of the outer shell 4 defines a cylindrical accommodation cavity. The cover plate assembly 1 may be disposed on the opening of the outer shell 4 and close the opening.

[0037] Reference Figure 2 The electrode assembly 2 is disposed in the inner cavity of the housing 4. A tab 21 is provided at one end of the electrode assembly 2 facing the cover assembly 1. The tab 21 is electrically connected to the cover assembly 1. For example, the cover assembly 1 can be a negative cover plate, and the tab 21 can be a negative tab. The negative cover plate and the negative tab can be directly welded to achieve electrical connection. Alternatively, the negative cover plate and the negative tab are electrically connected through an intermediate adapter such as a current collector plate 3. At this time, both the negative cover plate assembly 1 and the negative tab are welded to the current collector plate 3.

[0038] Combined with Figure 2 The housing 4 further includes a side wall 41 and a top wall 42. The side wall 41 surrounds the periphery of the top wall 42. The top wall 42 is located at one end of the side wall 41 opposite to the opening. The battery 100 further includes a positive current collector plate 5 and a terminal 6. The terminal 6 passes through the top wall 42. A positive tab 223 is provided at one end of the electrode assembly 2 facing the terminal 6. The positive current collector plate 5 is disposed between the terminal 6 and the electrode assembly 2. The positive current collector plate 5 is welded to the terminal 6 and the positive tab 223 of the electrode assembly 2 respectively.

[0039] Optionally, referring to Figure 6 The electrode assembly 2 may include a positive electrode plate 22, a negative electrode plate 23, and a separator 24. Among them, the positive electrode plate 22 includes a positive current collector 221 and a positive active coating 222 coated on the surface of the positive current collector 221. The negative electrode plate 23 includes a negative current collector 231 and a negative active coating 232 coated on the surface of the negative current collector 231. Taking the battery 100 as a cylindrical battery as an example, the positive electrode plate 22, the separator 24, and the negative electrode plate 23 are stacked in sequence and then wound to form a wound electrode assembly 2.

[0040] Combined with Figures 1-4 The cover assembly 1 may include: a cover plate 11 and a seal 12.

[0041] Referring to Figure 3 Among them, the cover plate 11 has a first surface and a second surface. The first surface and the second surface are opposite to each other along the thickness direction of the cover plate 11. Among them, the first surface can be the surface of the cover plate 11 on the side facing away from the inside of the battery 100, that is, the outer surface of the cover plate 11. The second surface can be the surface of the cover plate 11 on the side facing the inside of the battery 100, that is, the inner surface of the cover plate 11. A part of the structure of the first surface is recessed toward the second surface to form a sealing groove 112. A liquid injection hole 114 is provided at the bottom wall of the sealing groove 112. The liquid injection hole 114 is used to inject electrolyte into the battery 100.

[0042] The cover assembly 1 further includes a seal 12. The seal 12 is received in the sealing groove 112 so that the seal 12 seals the sealing groove 112, thereby achieving the sealing of the liquid injection hole 114. The seal 12 can be a sealing sheet, a sealing nail, or other sealing structural members adapted to the sealing groove 112.

[0043] The side wall of the sealing groove 112 includes a mating section 119 that mates with the outer periphery of the seal. The mating section 119 includes a first chamfer 115. Taking Figure 3 a perspective as an example, the first chamfer 115 is located at one end of the mating section 119 away from the second surface. It can be understood that since the cover plate 11 is a metal part, considering the processability, the sealing groove 112 can be formed by stamping the cover plate 11, and the first chamfer 115 is formed during the stamping process of the cover plate 11. Since the depth of the sealing groove 112 is limited, when the radius of the first chamfer 115 is relatively large compared to the depth of the sealing groove 112, after the seal 12 is assembled into the sealing groove 112, there will be a large gap between the mating section 119 of the side wall of the sealing groove 112 and the side surface of the seal 12. In this case, when using a welding device (such as a laser welding device) to weld the gap between the mating section 119 of the sealing groove 112 and the side surface of the seal 12, problems such as virtual welding and false welding may occur, which is not conducive to ensuring the sealing performance of the sealing groove 112 and the liquid injection hole 114.

[0044] In view of this, in this embodiment, a first stamping groove 117 that is recessed toward the first surface is provided in the area of the second surface of the cover plate 11 corresponding to the first chamfer 115. The first stamping groove 117 can be formed by stamping the cover plate 11. The first stamping groove 117 is located outside the sealing groove 112 along the radial direction of the cover plate 11. At this time, the first stamping groove 117 and the sealing groove 112 are separated by the side wall of the sealing groove 112. It can be understood that during the forming process of the first stamping groove 117, the stamping device presses the second surface of the cover plate 11, causing the cover plate material at the first stamping groove 117 to flow toward the first surface side (the flow of the metallographic structure), making the first chamfer 115 smaller. After the seal 12 is assembled into the sealing groove 112, the gap between the mating section 119 on the side wall of the sealing groove 112 and the side surface of the seal 12 will be greatly reduced, and the fitting effect between the mating section 119 and the seal 12 is better. In this way, when using a laser welding device to weld the gap between the side wall of the sealing groove 112 and the side surface of the seal 12, problems such as virtual welding and false welding can be prevented, thereby ensuring the sealing performance of the peripheral edge of the opening of the sealing groove 112, and further realizing the sealing of the liquid injection hole 114, preventing the battery 100 from leaking liquid and short-circuiting.

[0045] According to the cover plate assembly 1 of the embodiment of the present utility model, a sealing groove 112 is provided on the first surface of the cover plate 11, a liquid injection hole 114 for injecting liquid is provided in the sealing groove 112, the sealing member 12 is arranged in the sealing groove 112, and a first stamping groove 117 is provided on the second surface of the cover plate 11. In this way, by processing the first stamping groove 117, the stamping device can extrude and push the cover plate material at the first stamping groove 117 to flow towards the first surface side, making the first chamfer 115 smaller. In this way, after the sealing member 12 is assembled into the sealing groove 112, the fitting section 119 on the side wall of the sealing groove 112 and the side surface of the sealing member 12 are more closely attached, so as to facilitate welding and sealing the gap between the fitting section 119 of the sealing groove 112 and the side surface of the sealing member 12 by using a welding device, and prevent problems such as virtual soldering and false soldering, thereby achieving good sealing of the liquid injection hole 114 area and preventing the battery 100 from leaking liquid and short - circuiting.

[0046] Reference Figure 3 , in some embodiments, the stamping direction of the first stamping groove 117 is towards the first chamfer 115. Here, the stamping direction is the direction of the extrusion force applied to the cover plate 11 by a processing device such as a stamping device when processing the first stamping groove 117. The direction of this extrusion force can be directly opposite to the first chamfer 115, or there can be a component force of the extrusion force pointing to one side of the first chamfer 115. In this way, it can be ensured that the cover plate material between the first stamping groove 117 and the sealing groove 112 mainly flows towards the side surface of the sealing member 12, reducing the flow in other directions, so as to ensure the tightness of the fit between the side wall of the sealing groove 112 and the side surface of the sealing member 12, in order to improve the welding quality of the cover plate 11 and the sealing member 12.

[0047] In some embodiments, the first stamping groove 117 has a groove cross - section intercepted along a reference plane. The reference plane can be determined by the central axis of the cover plate 1 and any radial line. In other words, the reference plane passes through the central axis and the radial line of the cover plate 1. Since the first stamping groove 117 is an annular shape around the cover plate 1 for one week, the groove cross - section of the first stamping groove 117 at the reference plane includes two parts, which are respectively located on both sides of the central axis of the cover plate 1.

[0048] In this embodiment, the part of the groove cross - section of the first stamping groove 117 on any one side of the central axis of the cover plate 1 along the radial direction is a symmetric structure, and the symmetry center line is parallel to the axis of the cover plate 11. At this time, the opening direction of the first stamping groove 117 is along the axial direction of the cover plate 11. For example, the first stamping groove 117 can be formed into a V - shape, a U - shape or other symmetric structures. In this way, the structure of the first stamping groove 117 is relatively simple and easy to process.

[0049] In other embodiments, reference Figure 3, a part of the groove cross-section of the first stamping groove 117 on either side of the central axis of the cover plate 1 in the radial direction can be an asymmetric structure. The point in the first stamping groove 117 closest to the first surface (i.e., the deepest part of the first stamping groove 117) is located on the side closer to the liquid injection hole 114 (i.e., the radial inner side) of the center line L1 of the groove cross-section of any part (one of the above two parts) of the first stamping groove 117 in its width direction. Here, the width direction of the first stamping groove 117 is parallel to the radial direction of the cover plate 11. Thus, compared with the scheme where the first stamping groove 117 is a symmetric structure, in the present embodiment when processing the first stamping groove 117, the material of the cover plate 11 between the first stamping groove 117 and the first chamfer 115 can mainly flow and deform towards the side of the seal 12, reducing the flow and deformation of the material in other directions. This can not only improve the forming efficiency of the first stamping groove 117 but also ensure the tight fit between the cover plate 11 and the seal 12.

[0050] Reference Figure 3 and Figure 4 , in some embodiments, a part of the structure of the first surface is recessed towards the second surface to form a first-level sunken groove 111, and the seal groove 112 is a second-level sunken groove formed by the partial bottom wall of the first-level sunken groove 111 recessed towards the second surface. That is to say, the seal groove 112 and the surface of the cover plate 11 form a two-level stepped structure, and the seal 12 is arranged in the second-level sunken groove, and the liquid injection hole 114 is also formed on the bottom wall of the second-level sunken groove. The first chamfer 115 is located at the connection between the bottom wall of the first-level sunken groove 111 and the side wall of the second-level sunken groove, and the first stamping groove 117 is formed at a position on the second surface corresponding to the bottom wall of the first-level sunken groove 111. In this way, the first stamping groove 117 is opposite to the side wall of the seal groove 112 in the radial direction. Thus, during the process of processing the first stamping groove 117 by using a processing device such as a stamping device, the material of the cover plate 11 between the first stamping groove 117 and the first chamfer 115 can be effectively extruded to move towards the direction of the first chamfer 115, so that the first chamfer 115 becomes smaller. After the seal 12 is accommodated in the seal groove 112, the gap between the side wall of the seal groove 112 and the side surface of the seal 12 becomes smaller, and the welding effect is better, avoiding welding quality problems.

[0051] In addition, it should be noted that when welding the side wall of the seal groove 112 and the side surface of the seal 12, the molten pool formed by welding may form a protrusion after solidification. In the present embodiment, by using the second-level sunken groove as the seal groove 112 for installing the seal 12, a certain space can be reserved for the protrusion in the height direction by the first-level sunken groove 111, avoiding the protrusion exceeding the surface of the cover plate 11 and causing the surface of the cover plate 11 to be uneven, which affects the heat dissipation effect when the battery 100 is integrated into the module.

[0052] Reference Figure 3 and Figure 4, in some embodiments, the thickness of the bottom wall of the first-stage sink 111 is T1, and the depth of the first stamping groove 117 in the thickness direction of the cover plate 11 is T2. T1 and T2 satisfy: 0.8 ≤ T2 / T1 < 1. For example, the ratio of T2 to T1 can be 0.8, 0.85, 0.9, 0.95, etc. Of course, the present utility model does not limit this. The ratio of the depth T2 of the first stamping groove 117 to the thickness T1 of the bottom wall of the first-stage sink 111 can be reasonably selected within the above range according to actual needs. In this way, on the one hand, when the depth of the first stamping groove 117 is too small, the extrusion amount of the material of the cover plate 11 between the first stamping groove 117 and the sealing groove 112 during the forming process of the first stamping groove 117 is too small, resulting in the inability of the side wall of the sealing groove 112 to effectively fit with the side surface of the seal 12, and the welding quality is poor. On the other hand, it is avoided that the first stamping groove 117 penetrates the bottom wall of the first-stage sink 111, resulting in the breakage and scrapping of the cover plate 11.

[0053] Reference Figure 3 and Figure 4 , in some embodiments, the value range of the thickness T1 of the bottom wall of the first-stage sink 111 in the thickness direction of the cover plate 11 is: 0.1 mm ≤ T1 ≤ 1.2 mm. For example, the thickness T1 of the bottom wall of the first-stage sink 111 in the thickness direction of the cover plate 11 can be 0.1 mm, 0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, 1 mm, 1.1 mm, or 1.2 mm. Of course, the present utility model does not limit this. The thickness T1 of the bottom wall of the first-stage sink 111 in the thickness direction of the cover plate 11 can be reasonably selected within the above range according to actual needs. In this way, on the one hand, it is avoided that the thickness of the bottom wall of the first-stage sink 111 is too small, such as less than 0.1 mm, which increases the difficulty of processing the first stamping groove 117 and the space available for the forming of the first stamping groove 117 is too small. On the other hand, when the thickness of the bottom wall of the first-stage sink 111 is too large, it is difficult to process the sealing groove 112, and the first chamfer 115 of the formed sealing groove 112 is too large, affecting the final fitting effect between the side wall of the sealing groove 112 and the side surface of the seal 12.

[0054] Reference Figure 3 and Figure 4, in some embodiments, the depth T2 of the first stamping groove 117 in the thickness direction of the cover plate 11 ranges from 0.03 mm to 0.6 mm. For example, the depth T2 of the first stamping groove 117 in the thickness direction of the cover plate 11 can be 0.03 mm, 0.05 mm, 0.1 mm, 0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm, or 0.6 mm. Of course, the present utility model does not limit this. The depth T2 of the first stamping groove 117 in the axial direction of the cover plate 11 can be reasonably selected within the above range according to actual needs. In this way, on the one hand, when the depth of the first stamping groove 117 is too small, for example, less than 0.03 mm, the extrusion amount of the material of the cover plate 11 between the first stamping groove 117 and the sealing groove 112 during the forming process of the first stamping groove 117 is too small, resulting in the inability of the groove wall of the sealing groove 112 to effectively fit with the side surface of the seal 12, and the welding quality is poor. On the other hand, when the depth of the first stamping groove 117 is too large, for example, greater than 0.6 mm, the cover plate 11 will be pressed through and damaged and scrapped. It can be understood that the depth of the first stamping groove 117 is always less than the wall thickness of the bottom wall of the first sinking groove 111.

[0055] In some embodiments, referring to Figure 4 , the width W1 of the first stamping groove 117 ranges from 0.1 mm to 2 mm. For example, the width of the first stamping groove 117 can be 0.1 mm, 0.2 mm, 0.4 mm, 0.5 mm, 0.8 mm, 0.9 mm, 1 mm, 1.2 mm, 1.5 mm, 1.8 mm, or 2 mm. Of course, the present utility model does not limit this. The width W1 of the first stamping groove 117 can be reasonably selected within the above range according to actual needs. In this way, when the width of the first stamping groove 117 is too small, the deformation amount of the material during the stamping process is small, it is difficult to effectively reduce the size of the first chamfer 115, and the processing difficulty is large. In addition, when the width of the first stamping groove 117 is too large, the overall deformation amount of the cover plate 11 is large.

[0056] Referring to Figure 3 and Figure 4 , in some embodiments, the radius R1 of the first chamfer 115 ranges from 0.1 mm to 1 mm. For example, the value of the radius R1 of the first chamfer 115 can be 0.1 mm, 0.2 mm, 0.4 mm, 0.5 mm, 0.8 mm, 0.9 mm, or 1 mm. Of course, the present utility model does not limit this. The radius R1 of the first chamfer 115 can be reasonably selected within the above range according to actual needs. That is to say, after the first stamping groove 117 is processed, the radius of the first chamfer 115 is reduced to the above range to ensure good fitting tightness between the side wall of the sealing groove 112 and the side surface of the seal 12, thereby improving the welding quality.

[0057] In some embodiments, the bottom wall of the sealing groove 112 is provided with a liquid injection extension portion 113 extending along the axial direction of the cover plate 11. Both ends of the liquid injection extension portion 113 are open. The liquid injection extension portion 113 defines a liquid injection hole 114. The cover plate assembly 1 may further include: a liquid injection plug, which is detachably arranged in the liquid injection hole 114, and the liquid injection plug may be a plastic part.

[0058] In addition to the above solution of using a seal to seal the sealing groove 112 and then seal the area where the liquid injection hole 114 is located, referring to Figure 3 and Figure 4 , the inventors of the present application considered that the liquid injection of the battery 100 is usually not completed at one time, and multiple liquid injections are required in the entire production process of the battery 100. Therefore, in this embodiment, by providing a liquid injection plug, the liquid injection hole 114 can be flexibly opened or closed according to the liquid injection needs, so as to seal the liquid injection hole 114 with the liquid injection plug when liquid injection is not required. Wherein, the connection between the inner wall surface of the liquid injection extension portion 113 (i.e., the inner hole wall of the liquid injection hole 114) and the bottom wall of the sealing groove 112 has a second chamfer 116. It can be understood that the second chamfer 116 is formed during the process of punching the liquid injection hole 114 in the cover plate 11 by a punching process. Since the thickness of the cover plate 11 itself is limited, the length of the liquid injection extension portion 113 formed by punching is limited in the axial direction. When the radius of the second chamfer 116 is too large, it is easy to cause the part of the liquid injection extension portion 113 that fits with the liquid injection plug (i.e., the part of the liquid injection extension portion 113 other than the second chamfer 116) to be too short, resulting in unstable installation of the liquid injection plug and affecting the sealing performance at the liquid injection hole 114. In other words, the radius of the second chamfer 116 has a great influence on the sealing performance at the liquid injection hole 114.

[0059] In view of this, in this embodiment, a second stamping groove 118 recessed toward the first surface is further provided in the area of the second surface opposite to the second chamfer 116. The second stamping groove 118 can also be formed by a stamping process. It can be understood that during the forming process of the second stamping groove 118, the stamping equipment presses the second surface of the cover plate 11, causing the cover plate material at the second stamping groove 118 to flow toward the first surface side (the flow of the metallographic structure), making the second chamfer 116 smaller. After the liquid injection plug is assembled into the liquid injection hole 114, the fitting area between the inner wall of the liquid injection hole 114 and the liquid injection plug increases, the gap between the inner hole wall of the liquid injection hole 114 and the liquid injection plug will be greatly reduced, the fitting effect between the inner hole wall of the liquid injection hole 114 and the liquid injection plug is better, the sealing performance is higher, and leakage during the production process of the battery 100 is prevented.

[0060] Referring to Figure 3 and Figure 4, in some embodiments, the material extrusion direction of the second stamping groove 118 faces the second chamfer 116. The material extrusion direction here refers to the direction of the extrusion force applied to the cover plate 11 by a processing device, such as a stamping device, when processing the second stamping groove 118. The direction of this extrusion force can be directly opposite to the second chamfer 116, or there can be a component force of the extrusion force pointing to the second chamfer 116. In this way, it can be ensured that the material of the cover plate 11 between the second stamping groove 118 and the second chamfer 116 mainly flows towards the liquid injection plug, reducing the flow in other directions, so as to ensure the tight fit between the inner wall of the liquid injection hole 114 and the liquid injection plug, and thus improve the sealing performance.

[0061] In some embodiments, the second stamping groove 118 has a groove cross-section intercepted along a reference plane. The reference plane can be determined by the central axis of the cover plate 1 and any radial line. In other words, the reference plane passes through the central axis and the radial line of the cover plate 1. Since the second stamping groove 118 is an annular shape around the cover plate 1 for one week, the groove cross-section of the second stamping groove 118 at the reference plane includes two parts, and the two parts are respectively located on both sides of the central axis of the cover plate 1.

[0062] In some embodiments, in this embodiment, the part of the groove cross-section of the second stamping groove 118 on any one side of the central axis of the cover plate 1 along the radial direction is a symmetric structure, and the symmetry center line is parallel to the axis of the cover plate 11. At this time, the opening direction of the second stamping groove 118 is along the axial direction of the cover plate 11. For example, the second stamping groove 118 can be formed into a V shape, a U shape or other symmetric structures. In this way, the structure of the second stamping groove 118 is relatively simple and easy to process.

[0063] In other embodiments, refer to Figure 3 , the part of the groove cross-section of the second stamping groove 118 on any one side of the central axis of the cover plate 1 along the radial direction can be an asymmetric structure. The point in the second stamping groove 118 that is closest to the first surface (i.e., the deepest part of the second stamping groove 118) is located on the side (i.e., the radial inner side) of the center line L2 of the groove cross-section of any part (one of the above two parts) of the second stamping groove 118 in its width direction, which is close to the liquid injection hole 114. Here, the width direction of the second stamping groove 118 is parallel to the radial direction of the cover plate 11. In this way, compared with the solution where the second stamping groove 118 is a symmetric structure, in this embodiment, when processing the second stamping groove 118, the material of the cover plate 11 between the second stamping groove 118 and the second chamfer 116 can mainly flow and deform towards the second chamfer 116, reducing the flow and deformation of the material in other directions. This can not only improve the forming efficiency of the second stamping groove 118, but also ensure the tight fit between the liquid injection plug and the inner wall of the liquid injection hole 114, and thus improve the sealing performance of the liquid injection hole 114.

[0064] Refer to Figure 3 and Figure 4, in some embodiments, the thickness of the bottom wall of the sealing groove 112 is T3, and the depth of the second stamping groove 118 in the thickness direction of the cover plate 11 is T4. T3 and T4 satisfy: 0.8 ≤ T4 / T3 < 1. For example, the ratio of T4 to T3 can be 0.8, 0.85, 0.9, 0.95, etc. Of course, the present utility model does not limit this. The ratio of the depth T4 of the second stamping groove 118 to the thickness T3 of the bottom wall of the sealing groove 112 can be reasonably selected within the above range according to actual needs. In this way, on the one hand, when the depth of the second stamping groove 118 is too small, the extrusion amount of the material of the cover plate 11 between the second stamping groove 118 and the second chamfer 116 during the forming process of the second stamping groove 118 is too small, resulting in the inability to form an effective fit between the hole wall of the liquid injection hole 114 and the liquid injection plug, and the sealing performance of the liquid injection hole 114 is poor; on the other hand, it is avoided that the second stamping groove 118 penetrates the bottom wall of the sealing groove 112, resulting in damage and scrapping of the cover plate 11.

[0065] Reference Figure 3 and Figure 4 , in some embodiments, the value range of the thickness T3 of the bottom wall of the sealing groove 112 is: 0.1 mm ≤ T3 ≤ 1.2 mm. For example, the thickness T3 of the bottom wall of the sealing groove 112 can be 0.1 mm, 0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, 1 mm, 1.1 mm, or 1.2 mm. Of course, the present utility model does not limit this. The thickness of the bottom wall of the sealing groove 112 can be reasonably selected within the above range according to actual needs. In this way, on the one hand, it is avoided that the thickness of the bottom wall of the sealing groove 112 is too small, such as less than 0.1 mm, which increases the difficulty of processing the second stamping groove 118 and the space available for the forming of the second stamping groove 118 is too small; on the other hand, when the thickness of the bottom wall of the sealing groove 112 is too large, it is difficult to process the liquid injection hole 114, and the second chamfer 116 of the formed liquid injection hole 114 is too large, affecting the fitting effect between the hole wall of the liquid injection hole 114 and the liquid injection plug.

[0066] Reference Figure 3 and Figure 4, in some embodiments, the depth T4 of the second stamping groove 118 in the thickness direction of the cover plate 11 has a value range of: 0.03 mm ≤ T4 ≤ 0.6 mm. For example, the depth T4 of the second stamping groove 118 in the thickness direction of the cover plate 11 can be 0.03 mm, 0.05 mm, 0.1 mm, 0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm or 0.6 mm. Of course, the present utility model does not limit this. The depth T4 of the second stamping groove 118 in the thickness direction of the cover plate 11 can be reasonably selected within the above range according to actual needs. In this way, on the one hand, when the depth of the second stamping groove 118 is too small, for example, less than 0.03 mm, the extrusion amount of the material of the cover plate 11 between the second stamping groove 118 and the second chamfer 116 during the forming process of the second stamping groove 118 is too small, resulting in the hole wall of the liquid injection hole 114 being unable to effectively fit with the liquid injection plug; on the other hand, when the depth of the second stamping groove 118 is too large, for example, greater than 0.6 mm, it will cause the cover plate 11 to be pierced and damaged. It can be understood that the depth of the second stamping groove 118 is always less than the wall thickness of the bottom wall of the sealing groove 112.

[0067] In some embodiments, referring to Figure 4 , the value range of the width W2 of the second stamping groove 118 is: 0.1 mm ≤ W2 ≤ 2 mm. For example, the width of the second stamping groove 118 can be 0.1 mm, 0.2 mm, 0.4 mm, 0.5 mm, 0.8 mm, 0.9 mm, 1 mm, 1.2 mm, 1.5 mm, 1.8 mm or 2 mm. Of course, the present utility model does not limit this. The width W2 of the second stamping groove 118 can be reasonably selected within the above range according to actual needs. In this way, when the width of the second stamping groove 118 is too small, the deformation amount of the material during the stamping process is small, making it difficult to effectively reduce the size of the second chamfer 116 and increasing the processing difficulty; in addition, when the width of the second stamping groove 118 is too large, it will cause a large overall deformation amount of the cover plate 11.

[0068] Referring to Figure 3 and Figure 4 , in some embodiments, the value range of the radius R2 of the second chamfer 116 is: 0.1 mm ≤ R2 ≤ 1 mm. For example, the value of the radius R2 of the second chamfer 116 can be 0.1 mm, 0.2 mm, 0.4 mm, 0.5 mm, 0.8 mm, 0.9 mm or 1 mm. Of course, the present utility model does not limit this. The radius R2 of the second chamfer 116 can be reasonably selected within the above range according to actual needs. That is to say, after the second stamping groove 118 is processed, the radius of the second chamfer 116 is reduced to the above range to ensure good fitting tightness between the inner wall of the liquid injection hole 114 and the liquid injection plug.

[0069] In some embodiments, the cover plate 11 further includes a body portion 110, which is composed of the portion of the cover plate 11 located radially outside the sealing groove 112. In other words, the body portion 110 is composed of the portion of the cover plate 11 that has not undergone stamping deformation. Among them, the thickness of the body portion 110 is T5, and the thickness of the bottom wall of the sealing groove 112 is T3. T5 and T3 satisfy: 0.03 ≤ T3 / T5 ≤ 0.95. For example, the ratio between the thickness T3 of the bottom wall of the sealing groove 112 and the thickness T5 of the body portion 110 can be 0.03, 0.1, 0.15, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9 or 0.95. Of course, the present utility model does not limit this. The ratio between the thickness T3 of the bottom wall of the sealing groove 112 and the thickness T5 of the body portion 110 can be reasonably selected within the above range according to actual needs. In this way, it is possible to ensure that the bottom wall of the sealing groove 112 has an appropriate thickness to ensure that the bottom wall portion of the sealing groove 112 has sufficient structural strength, so as to facilitate the setting of structures such as the sealing member 12 and the liquid injection plug, prevent deformation, and thus improve the structural stability of the cover plate assembly 1.

[0070] It should be noted that in this embodiment, by providing the first stamping groove 117 on the second surface of the cover plate 11, the tightness of the fit between the groove wall of the sealing groove 112 and the side surface of the sealing member 12 can be improved, and further the sealing performance of the periphery of the sealing groove 112 can be improved. By providing the second stamping groove 118 on the second surface of the cover plate 11, the tightness of the fit between the hole wall of the liquid injection hole 114 and the liquid injection plug can be improved, and further the sealing performance at the liquid injection hole 114 can be improved. Through the cooperation of the two groove structures such as the first stamping groove 117 and the second stamping groove 118, the sealing performance of the liquid injection hole 114 and its surrounding area (i.e., the sealing groove 112) can be improved to a large extent, preventing liquid leakage during the production process of the battery 100 or in the finished battery 100, and improving the reliability of the battery 100. As an optional embodiment, the cover plate 11 can be provided with only the first stamping groove 117, or only the second stamping groove 118.

[0071] Next, with reference to Figures 1-4 , the battery 100 according to the second aspect embodiment of the present utility model will be described.

[0072] Specifically, the battery 100 in this embodiment can be a primary battery 100 or a secondary battery 100. A primary battery 100 refers to a battery 100 that cannot be recharged and reused after discharging, and a secondary battery 100 refers to a battery 100 that can be activated by charging to continue use after discharging. The battery 100 can be a lithium-ion battery 100, a sodium-ion battery 100, a sodium-lithium-ion battery 100, a lithium metal battery 100, a sodium metal battery 100, a lithium-sulfur battery 100, a magnesium-ion battery 100, a nickel-cadmium battery 100, etc. The embodiments of the present application do not limit this.

[0073] The battery 100 may include: a housing 4, an electrode assembly 2, and the cover plate assembly 1 in the above embodiments. Specifically, the housing 4 defines a receiving cavity with one end open. For example, the housing 4 may be a cylindrical shape with an open top or bottom end, and the inner side of the housing 4 defines the receiving cavity.

[0074] The electrode assembly 2 is disposed in the receiving cavity of the housing 4. A tab 21 is provided at one end of the electrode assembly 2 facing the opening, and the tab 21 is a negative tab. A central hole is formed in the middle of the wound electrode assembly 2.

[0075] The cover plate assembly 1 seals the opening. Optionally, the tab can be electrically connected to the cover plate 11 of the cover plate assembly 1. At this time, the tab can be directly electrically connected to the cover plate 11, or can be electrically connected through an intermediate transfer member such as a current collector plate 3. Or, the tab can be insulated from the cover plate 11, and at this time the cover plate 11 is not charged. The liquid injection extension portion 113 on the cover plate 11 can be opposite to the central hole of the electrode assembly 2 or extend into the central hole to facilitate the injection of the electrolyte.

[0076] According to the battery 100 of the embodiment of the present invention, by providing the cover plate assembly 1 in the above embodiments, due to the good sealing performance of the liquid injection hole 114 and its surrounding area, the performance of the battery 100 is more reliable, the service life is longer, and the user experience can be improved.

[0077] In some embodiments, the battery 100 may further include: a current collector plate 3. Specifically, the current collector plate 3 is welded to the cover plate 11 and the tab respectively. That is to say, the current collector plate 3 can be used as an intermediate transfer member between the cover plate 11 and the tab. By providing the current collector plate 3, the current of the electrode assembly 2 can be better collected, the current-carrying capacity between the cover plate 11 and the tab, and the transmission reliability of the current can be improved.

[0078] In some embodiments, referring to Figure 5 , the bottom wall of the sealing groove 112 can be welded to the current collector plate 3, so as to realize the electrical connection between the cover plate 11 and the current collector plate 3. And, the welding area D on the bottom wall of the sealing groove 112 avoids the first stamping groove 117 and the second stamping groove 118 to prevent the laser welding device from welding through the positions where the first stamping groove 117 and the second stamping groove 118 of the cover plate 11 are located, thereby ensuring the welding quality.

[0079] Next, an electronic device according to the third aspect embodiment of the present invention will be described.

[0080] The electronic device of this embodiment can be a vehicle, a mobile phone, a portable device, a laptop computer, a ship, a spacecraft, an electric toy, an electric tool, etc. The vehicle can be a fuel vehicle, a gas vehicle or a new energy vehicle, and the new energy vehicle can be a pure electric vehicle, a hybrid vehicle or an extended-range vehicle, etc. The spacecraft includes an airplane, a rocket, a space shuttle, a spaceship, etc. The electric toy includes a fixed or mobile electric toy, for example, a game console, an electric vehicle toy, an electric ship toy, an electric airplane toy, etc. The electric tool includes a metal cutting electric tool, a grinding electric tool, an assembly electric tool and a railway electric tool, for example, an electric drill, an electric grinding wheel, an electric wrench, an electric screwdriver, a hammer drill, an impact electric drill, a concrete vibrator, a planer, etc. The electronic device can also be a battery module or a battery pack. The embodiments of the present application do not impose special restrictions on the above-mentioned electronic devices.

[0081] The electronic device may include: a device main body and a battery 100. The device main body may include a battery compartment, and the battery 100 is disposed in the battery compartment and electrically connected to the device main body. For example, a power supply interface may be provided in the battery compartment, and the battery 100 may be connected to the power supply interface.

[0082] According to the electronic device of the embodiment of the present invention, by providing the battery 100 in the above embodiment, since the battery 100 has higher reliability, it can store and supply energy for the electronic device more reliably, which is beneficial to improving the user experience.

[0083] It should be noted that the embodiments referred to in the specification as "one embodiment", "embodiment", "exemplary embodiment", "some embodiments", etc. may include specific features, structures or characteristics, but not necessarily every embodiment includes the specific feature, structure or characteristic. In addition, such phrases do not necessarily refer to the same embodiment. In addition, when combining an embodiment to describe a specific feature, structure or characteristic, it is within the knowledge scope of those skilled in the art to implement such a feature, structure or characteristic in combination with other embodiments, whether explicitly or implicitly described.

[0084] Generally speaking, the terms should be understood at least in part by their use in the context. For example, at least in part according to the context, the term "one or more" used in the text can be used to describe any feature, structure or characteristic in a singular sense, or can be used to describe a combination of features, structures or characteristics in a plural sense. Similarly, at least in part according to the context, terms such as "a" or "the" can also be understood to convey a singular usage or a plural usage.

[0085] It should be readily understood that the terms "on", "above", and "over" in this disclosure should be construed in the broadest manner so that "on" not only means "directly on something", but also includes the meaning of "on something" with intervening features or layers therebetween, and "above" or "over" not only includes the meaning of "above" or "over something", but may also include the meaning of "above" or "over something" with no intervening features or layers therebetween (i.e., directly on something).

[0086] In addition, for ease of explanation, spatial relative terms may be used in the text, such as "below", "beneath", "under", "above", "over", etc., to describe the relationship of one element or feature to another as shown in the figures. Spatial relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation shown in the figures. The device may have other orientations (rotated 90 degrees or at other orientations), and the spatial relative descriptors used in the text may be interpreted accordingly as well.

[0087] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application and are not intended to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some or all of the technical features; 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.

Claims

1. A cover plate assembly for a battery, characterized in that, Comprising: A cover plate and a seal. The cover plate has opposite first and second surfaces. Part of the structure of the first surface is recessed toward the second surface side to form a seal groove, and the seal is received in the seal groove. The side wall of the seal groove includes a mating section that mates with the outer periphery of the seal. The mating section includes a first chamfer. The bottom wall of the seal groove is provided with a liquid injection hole for injecting electrolyte into the battery interior. A first stamping groove recessed toward the first surface side is provided in the area of the second surface corresponding to the first chamfer.

2. The cover plate assembly according to claim 1, characterized in that, The stamping direction of the first stamping groove is toward the first chamfer.

3. The cover plate assembly according to claim 2, wherein, The first stamping groove has a groove cross-section intercepted along a reference plane. The reference plane is determined by the central axis of the cover plate and any one radial line. The part of the groove cross-section on either side of the central axis along the radial direction of the cover plate is a symmetric structure.

4. The cover plate assembly according to claim 2, wherein The first stamping groove has a groove cross-section intercepted along a reference plane. The reference plane is determined by the central axis of the cover plate and any one radial line. The part of the groove cross-section on either side of the central axis along the radial direction of the cover plate is an asymmetric structure. Moreover, the point closest to the first surface in the first stamping groove is located on the side of the center line L1 of the groove cross-section of the first stamping groove in its own width direction and close to the liquid injection hole.

5. The cover plate assembly according to claim 1, wherein, Part of the structure of the first surface is recessed toward the second surface to form a first-level sinking groove. The seal groove is a second-level sinking groove formed by the bottom wall of the first-level sinking groove recessed toward the second surface. The first chamfer is located at the connection between the bottom wall of the first-level sinking groove and the side wall of the second-level sinking groove. The first stamping groove is formed at a position on the second surface corresponding to the bottom wall of the first-level sinking groove.

6. The cover plate assembly according to claim 5, wherein The thickness of the bottom wall of the first-level sinking groove is T1, and the depth of the first stamping groove in the thickness direction of the cover plate is T2. The T1 and the T2 satisfy: 0.8 ≤ T2 / T1 < 1.

7. A cover plate assembly for a battery, characterized in that, Comprising: A cover plate. The cover plate has opposite first and second surfaces. Part of the structure of the first surface is recessed toward the second surface side to form a seal groove. The bottom wall of the seal groove is provided with a liquid injection extension portion extending along the axial direction of the cover plate, and the liquid injection extension portion defines a liquid injection hole. A liquid injection plug that is detachably provided in the liquid injection hole. The connection between the inner wall surface of the liquid injection extension portion and the bottom wall of the seal groove has a second chamfer. A second stamping groove recessed toward the first surface side is provided in the area of the second surface corresponding to the second chamfer.

8. The cover plate assembly according to claim 7, wherein, The material extrusion direction of the second stamping groove is toward the second chamfer.

9. The cover plate assembly according to claim 7, wherein, The thickness of the bottom wall of the seal groove is T3, and the depth of the second stamping groove in the thickness direction of the cover plate is T4. The T3 and the T4 satisfy: 0.8 ≤ T4 / T3 < 1.

10. The cover plate assembly according to any one of claims 1-9, characterized in that, The cover plate further includes a body portion, which is composed of the part of the cover plate located radially outside the seal groove. The thickness of the body portion is T5, and the thickness of the bottom wall of the seal groove is T3. The T5 and the T3 satisfy: 0.3 ≤ T3 / T5 ≤ 0.

95.

11. A battery, characterized in that, Comprising: A housing that defines a receiving cavity with an open end; An electrode assembly disposed within the receiving cavity; The cover assembly according to any one of claims 1-10, which seals the opening.

12. An electronic device, characterized in that, Comprising: The battery according to claim 11.

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