Secondary battery and electronic device

Abstract

The utility model provides a secondary battery and an electronic device, the secondary battery comprises: a housing having a peripheral side wall, one end of which defines an opening; an electrode assembly accommodated in the case; the cover plate assembly covers the opening and is connected with the peripheral side wall in a welded mode, the cover plate assembly is provided with a protruding part protruding towards the electrode assembly, and the protruding part is inserted into the opening and attached to the peripheral side wall; a first current collecting member disposed between the cap plate assembly and the electrode assembly and electrically connecting the cap plate assembly and the electrode assembly; in the first direction from the electrode assembly to the cover plate assembly, a gap is formed between the convex part and the first current collecting component, and the gap is at least partially used as a gas storage space. According to the technical scheme, at least the gas storage space in the secondary battery can be increased so as to ensure smooth exhaust.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, and more specifically, to a secondary battery and an electronic device. Background Art

[0002] In the field of new energy power batteries, secondary batteries refer to rechargeable batteries, also known as renewable batteries or storage batteries. Unlike primary batteries, secondary batteries can be charged and discharged multiple times through reverse charging for reuse. One type of secondary battery is a cylindrical battery, which is valued for its high volume energy density, simple structure, easy grouping, and ease of standardization. In cylindrical batteries, a current collecting member is usually provided near the opening of the shell, and the current collecting member is electrically connected to the shell of the cylindrical battery and the tabs of the electrode assembly (such as the negative tab), thereby achieving electrical connection between the shell and the electrode assembly.

[0003] In existing cylindrical batteries, the residual space between the battery's cover plate assembly and the electrode assembly, which can be used as a gas storage space, is typically small. This reduces the amount of gas that can be accommodated in the gas storage space, leading to undesirable changes in the battery's internal pressure. For example, this can result in higher internal pressure before the battery reaches its operating limit, causing the battery's explosion-proof valve to open prematurely before the battery reaches thermal runaway conditions. This situation undermines battery performance and is therefore undesirable. Utility Model Content

[0004] In view of the problems existing in the related art, the purpose of the present invention is to provide a secondary battery and an electronic device, which can at least increase the gas storage space inside the secondary battery to ensure smooth exhaust.

[0005] To achieve the above-mentioned objectives, an embodiment of the present invention provides a secondary battery, which may include: a shell having a peripheral side wall, one end of which is defined by an opening; an electrode assembly, housed in the shell; a cover plate assembly, covering the opening and welded to the peripheral side wall, the cover plate assembly having a protrusion protruding toward the electrode assembly, the protrusion being inserted into the opening and affixed to the peripheral side wall; a first current collecting member, arranged between the cover plate assembly and the electrode assembly, and electrically connecting the cover plate assembly and the electrode assembly; wherein, in a first direction from the electrode assembly to the cover plate assembly, there is a gap between the protrusion and the first current collecting member, and the gap is at least partially used as a gas storage space.

[0006] In some embodiments, a thickened portion that is in direct contact with the cover plate assembly is provided on the first current collecting member, and the thickened portion is welded to the cover plate assembly.

[0007] In some embodiments, the first current collecting member has a flat portion directly contacting the first tab of the electrode assembly, and a height from a top surface of the thickened portion to a surface of the flat portion facing away from the electrode assembly is H1, wherein 4 mm ≤ H1 ≤ 13 mm.

[0008] In some embodiments, the thickened portion is disposed on a surface of the flat portion facing away from the electrode assembly.

[0009] In some embodiments, the first current collecting member has a boss formed by stamping and protruding toward the cover plate assembly, and the thickened portion is provided on the boss.

[0010] In some embodiments, a gasket is provided between the cover plate assembly and the first current collecting member, the gasket overlaps with the protrusion of the cover plate assembly and the edge portion of the first current collecting member in the first direction, and the gasket is located outside the projection area of ​​the explosion-proof structure of the cover plate assembly in the first direction.

[0011] In some embodiments, the gasket has a groove that passes through the gasket in a second direction perpendicular to the first direction, and the gap between the electrode assembly and the case is in communication with the groove.

[0012] In some embodiments, a through hole is provided on the first current collecting member, and at least a portion of the through hole is exposed by the spacer.

[0013] In some embodiments, the first current collecting member is provided with a through hole extending longitudinally along the radial direction thereof, wherein at least a portion of the through hole increases in width from the inner side to the outer side of the first current collecting member in the radial direction.

[0014] An embodiment of the present invention further provides an electronic device, which may include any of the above-mentioned secondary batteries.

[0015] The beneficial technical effects of the utility model include:

[0016] By providing a gap between the convex portion of the cover plate assembly and the first current collecting member to serve as a gas storage space, the overall gas storage space within the secondary battery is increased, ensuring smooth gas discharge, preventing undesirable changes in battery internal pressure due to a reduced gas storage space, and preventing pressure relief before the battery reaches its critical operating conditions. The gap between the convex portion and the first current collecting member can be created by increasing the height of the thickened portion. To prevent safety issues caused by battery vibration, a spacer is provided between the cover plate assembly and the first current collecting member. The spacer provides support between the first cover plate of the cover plate assembly, the first current collecting member, and the electrode assembly, thereby preventing electrode assembly failure caused by battery vibration and enhancing battery safety. Grooves can also be provided in the spacer to provide a radial gas discharge path, preventing gas from being unable to escape from the circumferential sidewalls of the housing and potentially causing the housing to explode. Through-holes can also be provided in the first current collecting member. When the explosion-proof structure ruptures to release pressure, gas and material can pass through the through-holes, pushing the explosion-proof structure out. When the explosion-proof structure is not releasing pressure, the through-holes can be used to vent gas from within the battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, a brief introduction will be given below to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0018] Figure 1 is a front view of a secondary battery according to an embodiment of the present application.

[0019] Figure 2 The secondary battery according to the embodiment of the present application is Figure 1 Cross-sectional view along line X1-X1 in FIG.

[0020] Figure 3 According to the embodiment of this application Figure 2 A partially enlarged view of region A1 of the secondary battery in FIG.

[0021] Figure 4 and Figure 5 According to different embodiments Figure 3 Isometric view of the first current collecting component and the thickened portion.

[0022] Figure 6 According to another embodiment of the present application Figure 2 A partially enlarged view of region A1 of the secondary battery in FIG.

[0023] Figure 7 It is a three-dimensional schematic diagram of a cushion block according to an embodiment of the present application.

[0024] Figures 8A to 8C 4 and 5 are schematic diagrams of a first current collecting member having a through hole according to different embodiments.

[0025] Figure 9 is a schematic diagram of an electronic device including a secondary battery according to an embodiment of the present application. DETAILED DESCRIPTION

[0026] In order to better understand the spirit of the embodiments of the present application, the following is a further description of some preferred embodiments of the present application. It should be noted that the following embodiments and features in the embodiments can be combined with each other without conflict.

[0027] The embodiments of the present application will be described in detail below. Throughout this specification, identical or similar components and components having identical or similar functions are represented by similar reference numerals. The embodiments described herein with respect to the accompanying drawings are illustrative and diagrammatic and are intended to provide a basic understanding of the present application. The embodiments of the present application should not be construed as limiting the present application.

[0028] As used herein, the terms "substantially," "substantially," and "approximately" are used to describe and illustrate small variations. When used in conjunction with an event or circumstance, the terms may refer to instances where the event or circumstance occurred precisely as well as instances where the event or circumstance occurred very approximately.

[0029] In this specification, unless otherwise specified or limited, relative terms such as "central", "longitudinal", "lateral", "front", "rear", "right", "left", "inner", "outer", "lower", "higher", "horizontal", "vertical", "above", "below", "above", "below", "top", "bottom" and their derivatives (such as "horizontally", "downwardly", "upwardly", etc.) should be interpreted as referring to the directions described in the discussion or depicted in the drawings. These relative terms are only used for convenience of description and do not require that the present application be constructed or operated in a specific orientation.

[0030] For ease of description, “first,” “second,” “third,” etc. may be used herein to distinguish different components in a figure or a series of figures. “First,” “second,” “third,” etc. are not intended to describe the corresponding components.

[0031] Figure 1 A front view of a secondary battery 100 according to an embodiment of the present application is shown. Figure 2 The secondary battery 100 according to the embodiment of the present application is shown along Figure 11. A cross-sectional view taken along line X1-X1 in FIG. In this embodiment, a cylindrical secondary battery 100 is shown as an example. In some embodiments, the secondary battery 100 may be a 4680 cylindrical battery (46 mm in diameter and 80 mm in height), a 4695 cylindrical battery (46 mm in diameter and 95 mm in height), or a 46120 cylindrical battery (46 mm in diameter and 120 mm in height).

[0032] See also Figure 1 and Figure 2 , the secondary battery 100 may include a case 110 , a terminal 120 , an electrode assembly 130 , a first current collecting member 150 , a second current collecting member 160 , and a cap plate assembly 140 .

[0033] The shell 110 may specifically include an end wall 111 and a peripheral side wall 112 surrounding the end wall 111. As long as a stable sealing and electrical connection relationship can be formed, the connection between the end wall 111 and the peripheral side wall 112 can be achieved in a variety of ways, such as integral stamping, integral casting, or split welding. The peripheral side wall 112 can be cylindrical or surround along any other closed loop contour that can match the end wall 111. In this embodiment, the outer edge of the end wall 111 is circular, and the peripheral side wall 112 is cylindrical and surrounds the outer edge of the end wall 111. A accommodating cavity is formed in the shell 110 surrounded by the end wall 111 and the peripheral side wall 112, which is used to accommodate the electrode assembly 130, electrolyte (not shown) and other necessary battery components. Specifically, the diameter of the shell 110 can be determined according to the specific size of the electrode assembly 130, such as 18mm, 21mm, 46mm, etc. The shell 110 can be made of various materials, such as copper, iron, aluminum, steel, aluminum alloy, etc. In order to prevent the shell 110 from rusting during long-term use, a layer of rust-proof material such as metal nickel can be plated on the surface of the shell 110.

[0034] The electrode assembly 130 is housed within the casing 110. The electrode assembly 130 is primarily formed by winding or stacking positive and negative electrode sheets, with a separator typically interposed between the positive and negative electrode sheets. The positive electrode sheet includes a positive current collector and a positive active material. The positive active material is coated on the surface of the positive current collector. The positive current collector includes a coated area coated with the active material and an uncoated area. The uncoated area, when wound, forms the positive electrode tab of the electrode assembly 130. The negative electrode sheet also includes a negative current collector and a negative active material. The negative active material is coated on the surface of the negative current collector. The negative current collector includes a coated area coated with the active material and an uncoated area. The uncoated area, when wound, forms the negative electrode tab of the electrode assembly 130. For lithium-ion secondary batteries, for example, the positive current collector can be made of aluminum, and the positive active material layer includes the positive active material. The positive active material can be lithium cobalt oxide, lithium iron phosphate, ternary lithium, or lithium manganese oxide, among others. The negative electrode current collector can be made of copper. The negative electrode active material layer includes a negative electrode active material, which can be carbon or silicon. The separator can be made of materials such as PP (polypropylene) or PE (polyethylene). To protect and insulate the electrode assembly 130, an insulating film can be applied to the outside of the electrode assembly 130. The insulating film can be made of PP, PE, PET (polyethylene terephthalate), PVC (polyvinyl chloride), or other polymer materials.

[0035] A circular opening 113 may be formed at one end of the peripheral sidewall 112 facing away from the end wall 111. The electrode assembly 130 may include a first electrode tab 131 facing the opening 113 and a second electrode tab 132 facing the end wall 111. In this embodiment, the first electrode tab 131 is a negative electrode tab. The side of the housing 110 with the opening 113 is electrically connected to the first electrode tab 131, thereby carrying a negative charge. The second electrode tab 132 is a positive electrode tab. The terminal 120 is electrically connected to the second electrode tab 132, thereby carrying a positive charge. However, in other embodiments, the second electrode tab 132 may be a negative electrode tab and the first electrode tab 131 may be a positive electrode tab. A first current collecting member 150 is disposed at the end of the electrode assembly 130 facing the opening 113 and may be welded to the first electrode tab 131. The second electrode tab 132 may be electrically connected to the terminal 120 via a second current collecting member 160. In an embodiment where the secondary battery is a cylindrical battery, the electrode assembly 130 may have a central through hole 133, which may maintain smoother connectivity between the spaces at both ends of the electrode assembly 130. The central through hole 133 may serve as an exhaust path for gases generated by the electrode assembly 130 during operation.

[0036] The terminal 120 can pass through the end wall 111 and be insulated from the end wall 111. The terminal 120 can be constructed in any suitable form that allows it to pass through the end wall 111 and electrically connect to the second tab 132 of the electrode assembly 130. For example, the cross-section can be circular, square, prismatic, or a special profile that ensures stable electrical conductivity. The end of the terminal 120 facing the electrode assembly 130 passes through the end wall 111 and is electrically connected to the second tab 132 directly or indirectly. In this embodiment, the terminal 120 is indirectly electrically connected to the second tab 132 via the second current collecting member 160. The end of the terminal 120 facing the opening 113 is welded to the second current collecting member 160, and the side of the second current collecting member 160 facing away from the terminal 120 is welded to the second tab 132. The end of the terminal 120 facing away from the electrode assembly 130 is exposed to the exterior of the housing 110, forming the corresponding electrode (e.g., the positive electrode). The housing 110 forms the corresponding other electrode (e.g., the negative electrode). The terminal 120 can be made of a conductive metal material. For example, the material of the terminal 120 can be aluminum (Al). The terminal 120 is electrically insulated from the housing 110. The electrical insulation between the terminal 120 and the end wall 111 of the housing 110 can be achieved in various ways. For example, the insulation can be achieved by placing an insulating washer between the terminal 120 and the end wall 111.

[0037] The materials of the first and second current collecting members 150 and 160 can be selected based on the polarity of the tabs to which they are connected. For example, if the second current collecting member 160 is connected to the positive electrode tab, aluminum can be used for the second current collecting member 160, while copper can be used for the first current collecting member 150 connected to the negative electrode tab. The shapes and structures of the second and first current collecting members 160 and 150 are not limited, and should be suitable to ensure a stable and reliable electrical connection.

[0038] The cover assembly 140 is sealed on the opening 113 . Figure 3 According to the embodiment of this application Figure 2 A partial enlarged view of the area A1 of the secondary battery in FIG. Figure 3 As shown, the cover plate assembly 140 may include a first cover plate 141 and a second cover plate 142, wherein the outer edge shape of the first cover plate 141 corresponds to the shape of the opening 113, and the outer edge of the first cover plate 141 is welded to the peripheral side wall 112 to seal the opening 113. The outer edge of the first cover plate 141 and the peripheral side wall 112 may be welded by some welding method that can achieve a seal at the welding position.

[0039] The first cover plate 141 may include a through hole 1411, and the through hole 1411 passes through the first cover plate 141 along the thickness direction of the first cover plate 141. The shape of the through hole 1411 is not limited, and can be a circular, elliptical or other type with a closed contour. The second cover plate 142 is fixed on the first cover plate 141 and covers the through hole 1411. As long as the through hole 1411 can be effectively sealed, there are many ways for the second cover plate 142 to cover the through hole 1411, for example, the second cover plate 142 is welded to the first cover plate 141 and seals the through hole 1411. The shape of the second cover plate 142 can correspond to the through hole 1411. For example, when the through hole 1411 is circular, the second cover plate 142 is also circular, and when the through hole 1411 is square, the second cover plate 142 is also square. The shape of the second cover plate 142 does not need to correspond to the shape of the through-hole. For example, if the through-hole 1411 is circular, the second cover plate 142 can be square enough to cover the through-hole; if the through-hole 1411 is square, the second cover plate 142 can be round enough to cover the through-hole. Electrolyte can also be added to the housing 110 through the through-hole 1411. Furthermore, the first cover plate 141 can be directly or indirectly electrically connected to the first current collecting member 150 in any appropriate manner, so that the housing 110 forms a corresponding electrode (e.g., a negative electrode).

[0040] In this embodiment, the secondary battery 100 is a cylindrical battery. The peripheral sidewall 112 of the housing 110 forms a cylindrical shape. The outer edge of the first cover plate 141 is circular, and the outer edge of the first current collecting member 150 is also circular. The first current collecting member 150 may have an opening 152 formed therein. The opening 152 may be coaxially arranged with the first cover plate 141 and / or the central through hole 133 of the electrode assembly 130.

[0041] The first cover plate 141 may also be provided with an explosion-proof structure 1413, which is used to at least partially open when the air pressure inside the housing 110 reaches a certain level to release the pressure inside the housing 110. The type of the explosion-proof structure 1413 is not limited. Figure 3 In the embodiment shown, the explosion-proof structure 1413 includes a notch provided on the second cover plate 142, and the notch is provided on the side of the second cover plate 142 facing the electrode assembly 130. The notch may be an annular structure. It should be noted that the annular structure does not limit the notch to be in the shape of a circular ring or an elliptical ring. Of course, in other embodiments, the notch may also be other structures, so long as it can be opened when the pressure is greater than a set threshold. The location of the explosion-proof structure 1413 constructed as a notch is an area where the strength of the first cover plate 141 is relatively weak. When the air pressure inside the shell 110 exceeds a certain threshold, the weaker notch will rupture, and at this time the air pressure inside the shell 110 can be discharged from the rupture, thereby preventing the secondary battery from exploding from the shell.

[0042] The first cover plate 141 may also include a protrusion 145 that matches the opening 113, and the protrusion 145 protrudes toward the side of the electrode assembly 130. The protrusion 145 is inserted into the opening 113 and fits against the peripheral side wall 112, so that the outer edge of the protrusion 145 cooperates with the peripheral side wall 112. The protrusion 145 is used to guide the assembly of the first cover plate 141 and the opening 113, and the cooperation between the peripheral side wall 112 of the shell 110 and the first cover plate 141. It can quickly position the first cover plate 141 and the opening 113 along the circumferential direction, thereby improving the efficiency and position accuracy of the welding between the first cover plate 141 and the peripheral side wall 112. The protrusion 145 can be arranged in an integrated and continuous manner around the outer edge of the first cover plate 141, or multiple independent protrusions 145 can be arranged around the through hole 1411. In one embodiment, the protrusion 145 can be used to block the laser when welding the first cover plate 141 and the peripheral side wall 112. The connection method between the protrusion 145 and the first cover plate 141 is not limited and can be integrally stamped or formed by machining the protrusion 145 on the first cover plate 141 to remove material. In existing secondary batteries, the protrusion 145 is typically abutted or welded to the first current collecting member 150. However, this generally results in a smaller residual space between the cover plate assembly 140 and the electrode assembly 130 that can be used as a gas storage space.

[0043] In some embodiments of the present application, a gap 119 is provided between the protrusion 145 and the first current collecting member 150 in a first direction Z extending from the electrode assembly 130 toward the cap plate assembly 140 (in this embodiment, the first direction Z is parallel to the height of the secondary battery 100). The space corresponding to this gap 119 can be at least partially used as a gas storage space. In this technical solution, by providing the gap 119 between the protrusion 145 of the cap plate assembly 140 and the first current collecting member 150 as a gas storage space, the overall gas storage space within the secondary battery is increased, ensuring smooth exhaust, avoiding undesirable changes in the battery's internal pressure due to a too-small gas storage space, and preventing the battery from depressurizing before reaching its operating limit.

[0044] Continue to refer Figure 3 As shown, the first current collecting member 150 is provided with a thickened portion 172 welded to the cap plate assembly 140. In the first direction Z, the top surface 172t of the thickened portion 172 is higher than the bottom surface 145b of the protrusion 145. The provision of the thickened portion 172 serves to electrically connect the first current collecting member 150 to the cap plate assembly 140 and the housing 110. In this embodiment, by increasing the height of the thickened portion 172, a gap 119 is created between the protrusion 145 and the first current collecting member 150, thereby increasing the gas storage space within the secondary battery.

[0045] In some embodiments, the first current collecting member 150 may have a flat portion 151 that directly contacts the first tab 131 of the electrode assembly 130. The distance between the top surface 172t of the thickened portion 172 and the surface of the flat portion 151 facing away from the electrode assembly 130 defines a height H1. The height H1 of the thickened portion 172 may be 4 mm ≤ H1 ≤ 13 mm. The height H1 of the thickened portion 172 can be adjusted to adjust the height of the gap 119 in the first direction Z, ensuring that a gap 119 of appropriate height is generated between the protrusion 145 and the first current collecting member 150, thereby increasing the overall gas storage space within the secondary battery.

[0046] Figure 4 According to one embodiment Figure 3 An isometric view of the first current collecting member 150 and the thickened portion 172. Figure 3 and Figure 4 As shown, in some embodiments, the thickened portion 172 is provided on the surface of the flat portion 151 facing away from the electrode assembly 130. In this embodiment, the thickened portion 172 is located on the flat portion 151 around the opening 152 of the first current collecting member 150, and a portion of the bottom of the thickened portion 172 can be inserted into the opening 152. The thickened portion 172 can be formed by machining and provided on the first current collecting member 150.

[0047] In this embodiment, the first current collecting member 150 may further include a buffer portion 154 that protrudes relative to the flat portion 151 toward the cover plate assembly 140. The buffer portion 154 may be, for example, annular and surrounding the opening 152. The buffer portion 154 may buffer stress on the first current collecting member 150, reducing deformation of the first current collecting member 150. Furthermore, the buffer portion 154 may increase the structural strength of the first current collecting member 150, thereby improving the service life of the first current collecting member 150.

[0048] Figure 5 FIG is an isometric view of the first current collecting member 150 and the thickened portion 172 according to another embodiment. Figure 5 In the embodiment shown, the first current collecting member 150 may have a stamped shape facing the cover plate assembly 140 (see FIG. Figure 3 ) The raised boss 159. The boss 159, formed by stamping, is hollow. The thickened portion 172 can be provided on the boss 159. The boss 159 can also be formed using a mold. Forming the boss 159 by stamping or mold is more suitable for mass production. Because the boss 159 is hollow, it can reduce material usage and further contribute to reducing the weight of the first current collecting member 150.

[0049] Return Reference Figure 3After increasing the gas storage space by configuring the spacer 119, except for the position of the thickened portion 172 of the first current collecting member 150, there are gaps between other positions and the cover assembly 140. Such gaps may cause the electrode assembly 130 to vibrate in the shell 110 and collide with other structures when the battery vibrates, resulting in defects in the electrode assembly 130 (such as internal short circuit), which reduces the safety of the battery.

[0050] In order to avoid the above problems, Figure 6 As shown, in some embodiments, a spacer 180 may be provided between the cap assembly 140 and the first current collecting member 150. In some embodiments, the spacer 180 may be in the shape of a closed ring extending along the peripheral sidewall 112 of the housing 110. In this embodiment where the secondary battery 100 is a cylindrical battery, Figure 6 and Figure 7 As shown, the spacer 180 may be annular and overlap with the outer edge of the first current collecting member 150 in the first direction Z.

[0051] The spacer 180 can overlap the protrusion 145 of the cap plate assembly 140 in the first direction Z. The spacer 180 also overlaps the edge portion of the first current collecting member 150 in the first direction Z. This allows the spacer 180 to be fixed in position in the first direction Z and in a second direction X perpendicular to the first direction Z. The spacer 180 provides support between the first cap plate 141 of the cap plate assembly 140, the first current collecting member 150, and the electrode assembly 130. This prevents the electrode assembly 130 from vibrating within the housing 110 or colliding with other structures during battery vibration, thereby preventing defects in the electrode assembly 130 caused by battery vibration and enhancing battery safety. Furthermore, because the spacer 180 overlaps with the protrusion 145, the size of the spacer 180 can match the size of the housing 110. This allows the spacer 180 to cooperate with the peripheral sidewall 112 of the housing 110 to limit its position, facilitating assembly. Furthermore, the spacer 180 can be prevented from having an excessively small outer diameter, which would cause it to wobble within the housing 110. Furthermore, the spacer 180 is positioned outside the projection area of ​​the explosion-proof structure 1413 of the cover assembly 140 in the first direction Z. This positioning prevents the spacer 180 from interfering with the explosion-proof structure 1413, thereby preventing it from affecting the release of internal battery pressure.

[0052] In some embodiments, the material of the spacer 180 can be the same as that of the first current collecting member 150, or the material of the spacer 180 can be the same as that of the first cover plate 141, the second cover plate 142, or the housing 110 of the cover plate assembly 140. In some embodiments, the material of the spacer 180 can be a high-temperature and electrolyte-resistant plastic, such as LCP (liquid crystal polymer).

[0053] Furthermore, the gasket 180 may have at least one groove 182. The groove 182 passes through the gasket 180 in a second direction X (i.e., a radial direction of the secondary battery) perpendicular to the first direction Z. A gap may exist between the gasket 180 and the peripheral sidewall 112 of the housing 110. The groove 182 may connect the gap between the electrode assembly 130 and the housing 110 to the groove 182.

[0054] After the spacer 180 is set, the spacer 180 will affect the battery exhaust. For example, the spacer 180 may block the exhaust path between the gap between the electrode assembly 130 and the shell 110 and the gas storage space, making it difficult for the gas in the gap between the electrode assembly 130 and the shell 110 to enter the gas storage space. The gas in the gap cannot be discharged and may cause the shell to explode (explode). The embodiment of the present application provides a radial exhaust path by providing a groove 182 in the spacer 180. For example, it can enable the gas in the gap between the electrode assembly 130 and the shell 110 to enter the gas storage space on the side of the explosion-proof structure 1413 of the cover plate assembly 140, thereby avoiding the gas at the peripheral side wall 112 of the shell 110 from being unable to be discharged and causing the shell to explode.

[0055] In some embodiments, reference Figures 3 to 6 As shown, at least one through-hole 157 may be provided on the first current collecting member 150. At least a portion of the through-hole 157 may be exposed by the spacer 180, that is, the spacer 180 is not located above at least a portion of the through-hole 157, so that the gas generated by the electrode assembly 130 during operation can be discharged from the through-hole 157 to the gas storage space between the cap plate assembly 140 and the electrode assembly 130, thereby providing an exhaust path in the first direction Z.

[0056] On the other hand, because the projected area of ​​explosion-proof structure 1413 in first direction Z is generally smaller than the projected area of ​​first current collecting member 150, and because first current collecting member 150 is welded to cover plate assembly 140 via thickened portion 172, when explosion-proof structure 1413 ruptures to release pressure, first current collecting member 150 may pull on cover plate assembly 140, preventing cover plate assembly 140 from being discharged. Furthermore, when explosion-proof structure 1413 ruptures to release pressure, a certain amount of gas and material thrust is required to push out explosion-proof structure 1413. However, in reality, some gas and material are blocked by first current collecting member 150, which also prevents cover plate assembly 140 from being discharged. In the embodiment of the present application, by providing a through hole 157 in the first current collecting member 150, when the explosion-proof structure 1413 ruptures to release pressure, gas and substances can pass through the through hole 157 and push the explosion-proof structure 1413 to be discharged; and when the explosion-proof structure 1413 is not releasing pressure, the through hole 157 can be used to exhaust the inside of the battery.

[0057] The through hole 157 can be of any suitable shape and position. Figure 4 and Figure 5 As shown, in some embodiments, the through hole 157 extends longitudinally along the radial direction of the first current collecting member 150, and at least a portion of the through hole 157 increases in width from the inner side to the outer side of the first current collecting member 150 in the radial direction. Figure 4 and Figure 5 The through holes 157 may be arranged at intervals around the opening 152 in the shape of a water drop as shown. In a top view, the two ends 157a and 157c of the through hole 157 may have arc-shaped edges, and the width of the middle portion 157b of the through hole 157 connected between the two ends 157a and 157c gradually increases from the inside to the outside of the first current collecting member 150. In addition, the size of the end 157c located on the outside is larger than that of the end 157a. Figure 3 At Figure 5 As shown, the width of the through-hole 157 located on the outer ring of the electrode assembly 130 is relatively large. Since the circumference of each circle of the electrode pieces is longer on the outer ring of the electrode assembly 130, more gas will be generated between the electrode pieces. By configuring the through-hole 157 on the outer ring of the electrode assembly 130 to have a larger width, the area for exhaust at the outer ring is larger, thereby providing a more reasonable exhaust path for the electrode assembly. It should be understood that the through-hole 157 can also have other appropriate shapes. As long as at least a portion of the through-hole 157 increases in width from the inside to the outside, a larger exhaust area can be provided on the outer ring of the electrode assembly.

[0058] In another example, the through hole 157 may be in an oblong shape, such as Figure 8A As shown, both ends of the through hole 157 may be arc-shaped, and the width of the middle portion between the two ends of the through hole 157 remains constant in the direction from the inside to the outside of the first current collecting member 150. A plurality of through holes 157 may be spaced around the opening 152. Each through hole 157 may extend longitudinally in the direction from the inside to the outside of the first current collecting member 150. In another example, the through holes 157 may be provided at the periphery of the first current collecting member 150 and on the buffer portion 154, as shown in FIG. Figure 8B As shown, the through hole 157 can be circular or oblong in shape. In one example, the through hole 157 is located below the connecting bridge structure 158, as shown in FIG. Figure 8C As shown, the connection bridge structure 158 may be formed on the first current collecting member 150 by stamping.

[0059] See also Figure 9 An embodiment of the present application further provides a battery pack 1002 , comprising any one of the secondary batteries 100 described above, and the battery pack 1002 can have the beneficial effects described above with respect to the secondary battery 100 .

[0060] The embodiments of the present application also provide an electronic device 1000, which includes the above-mentioned battery pack 1002. For the convenience of explanation, the following embodiments take the electronic device 1000 as an example of a vehicle. A battery pack 1002 is provided inside the vehicle, and the battery pack 1002 can be provided at the bottom, head, or tail of the vehicle body 1001. The battery pack 1002 can be used to power the vehicle. For example, the battery pack 1002 can be used as an operating power source for the vehicle. The working part of the electronic device 1000 is electrically connected to the battery pack 1002 to obtain power support. The vehicle can be a fuel vehicle, a gas vehicle, or a new energy vehicle. The new energy vehicle can be a pure electric vehicle, a hybrid vehicle, or an extended-range vehicle, etc., but is not limited thereto. The working part is the vehicle body, and the battery pack 1002 is provided at the bottom of the vehicle body to provide power support for the driving of the vehicle or the operation of the electrical components in the vehicle.

[0061] In some other embodiments, the electronic device 1000 can also be a mobile phone, a portable device, a laptop computer, a ship, a spacecraft, an electric toy, an electric tool, and the like. The spacecraft includes airplanes, rockets, space shuttles, and spacecraft, and the like; the working part can obtain the electric energy of the battery pack 1002 and perform corresponding work, such as the fan blade rotation unit of a fan, the dust collection unit of a vacuum cleaner, and the like. The electric toy includes fixed or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, and the like; the electric tool includes metal cutting electric tools, grinding electric tools, assembly electric tools, and railway electric tools, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete vibrators, and electric planers, and the like. The embodiments of the present application do not impose any special restrictions on the above-mentioned electronic device 1000.

[0062] In summary, in the secondary battery 100 of the present application, a gap 119 is provided between the protrusion 145 of the cap plate assembly 140 and the first current collecting member 150 to serve as a gas storage space. This increases the overall gas storage space within the secondary battery, ensuring smooth gas discharge, preventing undesirable changes in battery internal pressure due to a reduced gas storage space, and preventing pressure relief before the battery reaches its critical operating conditions. The gap 119 can be created between the protrusion 145 and the first current collecting member 150 by increasing the height of the thickened portion 172. Furthermore, to prevent safety issues caused by battery vibration, a spacer 180 is provided between the cap plate assembly 140 and the first current collecting member 150. Spacer 180 provides support between the first cap plate 141 of the cap plate assembly 140, the first current collecting member 150, and the electrode assembly 130, thereby preventing defects in the electrode assembly 130 caused by battery vibration and enhancing battery safety. A groove 182 may also be provided in the spacer 180 to provide a radial exhaust path to prevent gas from being unable to escape from the peripheral sidewall 112 of the housing 110, which could cause the housing to explode. A through hole 157 may also be provided in the first current collecting member 150. When the explosion-proof structure 1413 ruptures to release pressure, gas and material can pass through the through hole 157 and push the explosion-proof structure 1413 out. When the explosion-proof structure 1413 is not releasing pressure, the through hole 157 can be used to exhaust gas from within the battery.

[0063] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that the present invention is susceptible to various modifications and variations. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A secondary battery, characterized in that: include: A housing having a peripheral sidewall, one end of the peripheral sidewall defining an opening; an electrode assembly housed in the housing; a cover plate assembly covering the opening and welded to the peripheral side wall, the cover plate assembly having a convex portion protruding toward the electrode assembly, the convex portion being inserted into the opening and affixed to the peripheral side wall; a first current collecting member disposed between the cap plate assembly and the electrode assembly and electrically connecting the cap plate assembly and the electrode assembly; Wherein, in a first direction from the electrode assembly toward the cap plate assembly, there is a gap between the protrusion and the first current collecting member, and the gap is at least partially used as a gas storage space.

2. The secondary battery according to claim 1, wherein The first current collecting component is provided with a thickened portion, and the thickened portion is welded to the cover plate assembly.

3. The secondary battery according to claim 2, wherein The first current collecting member has a flat portion in direct contact with the electrode assembly. A height from a top surface of the thickened portion to a surface of the flat portion facing away from the electrode assembly is H1, wherein 4 mm ≤ H1 ≤ 13 mm.

4. The secondary battery according to claim 2, wherein: The first current collecting member has a flat portion in direct contact with the electrode assembly, and the thickened portion is provided on a surface of the flat portion facing away from the electrode assembly.

5. The secondary battery according to claim 2, wherein The first current collecting member has a boss formed by stamping and protruding toward the cover plate assembly, and the thickened portion is provided on the boss.

6. The secondary battery according to claim 1, wherein A spacer is provided between the cover plate assembly and the first current collecting member, the spacer overlaps with the protrusion of the cover plate assembly and the edge portion of the first current collecting member in the first direction, and the spacer is located outside the projection area of ​​the explosion-proof structure of the cover plate assembly in the first direction.

7. The secondary battery according to claim 6, characterized in that The gasket has a groove that passes through the gasket in a second direction perpendicular to the first direction, and a gap between the electrode assembly and the case communicates with the groove.

8. The secondary battery according to claim 6, wherein The first current collecting member is provided with a through hole, and at least a portion of the through hole is exposed by the spacer.

9. The secondary battery according to claim 1, wherein The first current collecting member is provided with a through hole extending longitudinally along the radial direction thereof, wherein at least a portion of the through hole increases in width from the inner side to the outer side of the first current collecting member along the radial direction.

10. An electronic device, characterized in that: The invention comprises the secondary battery according to any one of claims 1 to 9.

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