Secondary battery and electric device

Abstract

The invention provides a secondary battery and an electric device. The secondary battery includes an electrode assembly, a packaging member, and an adhesive member. The electrode assembly comprises an electrode main body and a tab, and the tab is electrically connected with the electrode main body. The electrode body is arranged in the packaging piece, one side of the packaging piece is provided with a first end face and a first edge sealing part folded towards the first end face in the first direction, and at least part of the tab extends out of the packaging piece from the first edge sealing part. The bonding piece is arranged between the first edge sealing part and the first end face and comprises a plurality of first bonding units arranged at intervals in the second direction, and the projection of the tab on the first end face and the projection of the first bonding units on the first end face are at least partially overlapped. The tabs comprise a first tab and a second tab, in the second direction, the area between the first tab and the second tab is a middle area, the area between the adjacent first bonding units is an interval area, and the middle area and the interval area are at least partially overlapped. And when gas is generated in the battery cell, the first edge sealing part can be effectively burst through.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and in particular to secondary batteries and electrical devices. Background Art

[0002] As electronic products become increasingly versatile, insufficient battery capacity has become a significant constraint on mobile phone battery life. Folding-top batteries can save packaging space, thereby increasing the length of the battery cell and boosting battery capacity. Folding-top batteries also significantly reduce the risk of top seal damage by redirecting the force applied to the top seal.

[0003] However, compared with non-folding top-seal batteries, existing folding top-seal batteries cannot effectively break open the top-seal structure to release pressure when gas is generated inside the battery cell, which poses risks of fire and explosion, reducing battery safety performance. Summary of the Invention

[0004] The present application provides a secondary battery and an electrical device to solve the above technical problems.

[0005] The embodiment of the present application is implemented as follows: A secondary battery comprises an electrode assembly, a packaging member, and an adhesive. The electrode assembly comprises an electrode body and a tab, which is electrically connected to the electrode body. The electrode body is disposed within the packaging member. Along a first direction, one side of the packaging member comprises a first end surface and a first edge seal. The first edge seal extends outward from the first end surface and is folded toward the first end surface. The tab at least partially protrudes from the packaging member through the first edge seal. The adhesive member is disposed between the first edge seal and the first end surface and is used to bond the first edge seal to the first end surface. The adhesive member comprises a plurality of first adhesive units. Along a second direction, the plurality of first adhesive units are spaced apart, with the projection of the tab on the first end surface at least partially overlapping with the projection of the first adhesive unit on the first end surface. The tab comprises a first tab and a second tab. Along the second direction, the region between the first tab and the second tab is a middle region, and the region between adjacent first adhesive units is a spacing region. The middle region and the spacing region at least partially overlap. The thickness direction of the secondary battery is a third direction, and the third direction, the first direction, and the second direction are mutually perpendicular.

[0006] In this way, the spacing area is a weak area of the adhesive, which partially overlaps with the middle area between the first pole ear and the second pole ear. When gas is generated inside the battery cell, the internal stress of the package due to the expansion of the gas can allow the first edge seal to be separated from the first end face in the weak area of the adhesive. The first edge seal is away from the first end face under the action of the internal stress, so that the gas can effectively break through the first edge seal and release the pressure in time, thereby fully reducing the risks of battery fire and explosion, and improving the safety performance of the battery.

[0007] In one possible embodiment, along the second direction, the length of the spacing area is a, where 3 mm ≤ a ≤ 10 mm. By constraining the size of the spacing area, the first edge seal can be effectively opened, thereby improving the battery test success rate and battery safety and reliability.

[0008] In one possible embodiment, along the second direction, one side of the package has a second end surface, and a distance b between the first adhesive unit proximate the second end surface and the second end surface is defined as "b," where 0 mm ≤ b ≤ 5 mm. By constraining the distance between the first adhesive unit and the second end surface, the placement of the adhesive can be optimized, allowing for efficient use of the adhesive.

[0009] In one possible embodiment, the adhesive member further includes a second adhesive unit disposed in the spacing region along the second direction. The junction between the first edge seal and the first end face is the first edge, and the side of the first edge seal extending beyond the tab is the second edge. Along the extension direction of the first edge seal, the distance between the first adhesive unit and the second edge is smaller than the distance between the second adhesive unit and the second edge, and the distance between the second adhesive unit and the first edge is smaller than the distance between the first adhesive unit and the first edge.

[0010] The provision of the second adhesive unit can enhance the folding and positioning effect of the first edge sealing portion. When gas is generated in the battery cell, since the second adhesive unit is close to the first edge, the corresponding force generated by the first edge sealing portion can overcome the adhesive force of the second adhesive unit, causing the first edge sealing portion at that location to deform. The internal gas can effectively break through the packaging from that location and release the pressure.

[0011] In a possible embodiment, the adhesive member further includes a third adhesive unit, which is located between the first adhesive unit and the second adhesive unit along the second direction; and the third adhesive unit connects the adjacent first adhesive unit and the second adhesive unit along the extension direction of the first edge sealing portion.

[0012] In a possible implementation manner, the distance between the first bonding unit and the second side is c, and the distance between the second bonding unit and the second side is d, wherein c<d; 0.1 mm≤c≤1 mm; and / or 1 mm≤d≤2.5 mm.

[0013] By constraining the position and size of the first bonding unit and the second bonding unit, the success rate of gas breaking through the first edge seal portion is increased, thereby improving the safety performance of the battery.

[0014] In one possible embodiment, the adhesive member further includes a second adhesive unit disposed in the spacing region along the second direction and connected to the adjacent first adhesive unit. Along the extension direction of the first edge seal, the first adhesive unit has a width e, and the second adhesive unit has a width f, where e>f.

[0015] In a possible implementation, along the extension direction of the first edge sealing portion, the width of the first bonding unit is e, where 1 mm ≤ e ≤ 5 mm; and / or the width difference between the first bonding unit and the second bonding unit is ef, where 0.2 mm ≤ ef ≤ 1 mm.

[0016] By restricting the width dimensions of the first bonding unit and the second bonding unit, the bonding force of the second bonding unit is made relatively small, thereby ensuring that the gas can effectively break open the first edge sealing portion.

[0017] In a possible implementation manner: along the second direction, the length of the second bonding unit is g, where 1 mm ≤ g ≤ 10 mm.

[0018] In a possible embodiment: the adhesive member is provided with an air avoidance area, the air avoidance area is located between adjacent first adhesive units, and along the extension direction of the first edge sealing portion, one side of the air avoidance area is connected to the second adhesive unit or both sides of the air avoidance area are respectively connected to the second adhesive unit.

[0019] In a possible implementation manner: along the second direction, the first bonding units are symmetrically distributed with the center line of the middle area as the center axis.

[0020] An embodiment of the present application further provides an electrical device, comprising an electrical component and the secondary battery described in the above embodiment, wherein the electrical component is electrically connected to the secondary battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying any creative work.

[0022] Figure 1 FIG. 1 is a schematic structural diagram of a secondary battery according to an embodiment of the present application.

[0023] Figure 2 for Figure 1 The diagram shows the structure of the secondary battery after the first edge sealing portion is folded toward the first end surface.

[0024] Figure 3 FIG. 1 is a schematic structural diagram of a secondary battery in another embodiment.

[0025] Figure 4 FIG. 1 is a schematic structural diagram of a secondary battery in another embodiment.

[0026] Figure 5 for Figure 4The diagram shows the structure of the secondary battery after the first edge sealing portion is folded toward the first end surface.

[0027] Figure 6 FIG. 1 is a schematic structural diagram of a secondary battery in another embodiment.

[0028] Figure 7 FIG. 1 is a schematic structural diagram of a secondary battery in another embodiment.

[0029] Figure 8 FIG. 1 is a schematic structural diagram of a secondary battery in another embodiment.

[0030] Figure 9 FIG. 1 is a schematic structural diagram of a secondary battery in another embodiment.

[0031] Figure 10 FIG. 1 is a schematic structural diagram of a secondary battery in another embodiment.

[0032] Figure 11 FIG. 1 is a schematic structural diagram of a secondary battery in another embodiment.

[0033] Figure 12 FIG. 1 is a simplified schematic diagram of a cross-sectional structure of a secondary battery in one embodiment.

[0034] Figure 13 FIG. 1 is a simplified schematic diagram of a cross-sectional structure of a secondary battery in one embodiment.

[0035] Figure 14 FIG. 1 is a schematic structural diagram of a secondary battery in another embodiment.

[0036] Figure 15 FIG. 1 is a schematic structural diagram of a secondary battery in another embodiment.

[0037] Figure 16 FIG. 1 is a simplified schematic diagram of an electrical device in one embodiment.

[0038] Description of main component symbols: Secondary battery 100 Electrode assembly 10 Electrode body 11 Tab 12 First tab 121 Second tab 122 Middle area 13 Center Line 14 Package 20 First end surface 21 First edge sealing portion 22 First side 221 Second side 222 Second end surface 23 Second edge sealing portion 24 Adhesive 30 First bonding unit 31 Second bonding unit 32 The third bonding unit 33 Spacing area 34 Air Refuge Area 35 First direction A Second direction B Electric device 200 Electrical components 201 The following specific implementation methods will further illustrate this application in conjunction with the above-mentioned drawings. DETAILED DESCRIPTION

[0039] The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments.

[0040] It should be noted that when an element is referred to as being "fixed to" another element, it may be directly on the other element or there may also be an element centered therein. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may also be an element centered therein. When an element is considered to be "set on" another element, it may be directly set on the other element or there may also be an element centered therein. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only.

[0041] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this application belongs. The terms used herein in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application. The term "or / and" as used herein includes any and all combinations of one or more of the relevant listed items.

[0042] Some embodiments of the present application are described in detail. In the absence of conflict, the following embodiments and features of the embodiments can be combined with each other.

[0043] See also Figures 1 to 15An embodiment of the present application provides a secondary battery 100, comprising an electrode assembly 10, a packaging member 20, and an adhesive member 30. The electrode assembly 10 comprises an electrode body 11 and a tab 12, with the tab 12 electrically connected to the electrode body 11. The electrode body 11 is disposed within the packaging member 20. Along a first direction A, one side of the packaging member 20 comprises a first end surface 21 and a first edge seal 22. The first edge seal 22 extends outward from the first end surface 21 and is folded toward the first end surface 21. The tab 12 at least partially protrudes from the packaging member 20 from the first edge seal 22. The adhesive member 30 is disposed between the first edge seal 22 and the first end surface 21, for bonding the first edge seal 22 to the first end surface 21. The adhesive member 30 comprises a plurality of first adhesive units 31, which are spaced apart along a second direction B. The projection of the tab 12 on the first end surface 21 at least partially overlaps with the projection of the first adhesive unit 31 on the first end surface 21. The tab 12 includes a first tab 121 and a second tab 122. Along the second direction B, the area between the first tab 121 and the second tab 122 is the intermediate area 13, and the area between adjacent first bonding units 31 is the spacing area 34. The intermediate area 13 and the spacing area 34 at least partially overlap. The thickness direction of the secondary battery 100 is the third direction, and the third direction, the first direction A, and the second direction B are perpendicular to each other. In the embodiment of the present application, the first direction A is the length direction of the secondary battery 100, and the second direction B is the width direction of the secondary battery 100. In the embodiment of the present application, the package 20 can be a packaging bag, including but not limited to an aluminum-plastic film packaging bag. The first end surface 21 can be the top end surface of the packaging bag, and the first edge seal portion 22 can be the top edge seal of the packaging bag.

[0044] As such, the spacing region 34 represents a weak area of the adhesive 30, weakening the connection strength between the first edge seal 22 and the first end face 21. The spacing region 34 partially overlaps the intermediate region 13 between the first and second tabs 121, 122. This allows gas generated within the battery cell to expand the packaging bag, squeezing the top intermediate region 13 of the packaging bag. The resulting internal stress can cause the first edge seal 22 to deform in the spacing region 34, separating the first edge seal 22 from the first end face 21 in the weak area of the adhesive 30. Under the action of the internal stress, the first edge seal 22 moves away from the first end face 21, allowing gas to effectively break through the first edge seal 22, releasing pressure in a timely manner, significantly reducing the risk of battery fire and explosion, and improving battery safety.

[0045] In order to clearly illustrate the characteristic structure of the secondary battery 100 in the embodiment of the present application, Figures 1 to 15 In the figure, the lower half of the electrode assembly 10, the packaging member 20 and other structures are omitted.

[0046] like Figure 1 and Figure 2 As shown, in some embodiments, two tabs 12 extend from the side of the first edge seal 22 away from the first end face 21, and two first bonding units 31 are provided corresponding to the two tabs 12. The first bonding units 31 are partially provided in the middle region 13 between the two tabs 12, and the spacing region 34 between the two first bonding units 31 overlaps with the middle region 13. After the first edge seal 22 is folded toward the first end face 21, the portion of the first edge seal 22 in the spacing region 34 is free of the adhesive 30. Gas generated inside the packaging bag can lift the first edge seal 22 from this region, moving the first edge seal 22 away from the first end face 21 and facilitating the opening of the first edge seal 22.

[0047] like Figure 3 As shown, in some embodiments, the number of first bonding units 31 can also be multiple, at least one first bonding unit 31 is provided corresponding to one tab 12, and multiple spaced first bonding units 31 can be provided in the middle region 13. In this way, the middle region 13 can overlap with multiple spaced regions 34. After the first edge seal 22 is folded toward the first end face 21, the first edge seal 22 in the middle region 13 is not prone to local rebound. At the same time, since the middle region 13 overlaps with multiple spaced regions 34, the bonding area between the first edge seal 22 and the first end face 21 is reduced. When the gas generated inside the packaging bag squeezes and impacts the middle region 13, the first edge seal 22 in the middle region 13 can be effectively deformed, and then the gas can lift the first edge seal 22 from the middle region 13, so that the first edge seal 22 is away from the first end face 21, which facilitates the first edge seal 22 to be opened and the pressure is released in time.

[0048] In some embodiments, the length of the spacer region 34 along the second direction B is a, where 3 mm ≤ a ≤ 10 mm. By constraining the size of the spacer region 34 , the first edge seal 22 can be effectively opened, thereby improving the battery test success rate and battery safety and reliability.

[0049] like Figure 4 and Figure 5 As shown, in some embodiments, the first edge seal 22 extends beyond three tabs 12, and two first bonding units 31 are provided corresponding to the tabs 12 at either end. The spacing region 34 between the two first bonding units 31 is provided corresponding to the middle tab 12. Gas generated within the packaging bag can lift the first edge seal 22 from the location of the middle tab 12, facilitating the opening of the first edge seal 22.

[0050] See also Figure 6In some embodiments, the number of first bonding units 31 may be three, and the three first bonding units 31 are respectively provided corresponding to the three tabs 12. In this way, the spacing area 34 between adjacent first bonding units 31 is also located between adjacent tabs 12. The gas generated inside the packaging bag can lift the first edge seal 22 from the area between adjacent tabs 12, facilitating the opening of the first edge seal 22.

[0051] In other embodiments, the number of tabs 12 may be more than three, and the number of first bonding units 31 may be more than three, as long as the design requirements are met. This application is not limited thereto.

[0052] In some embodiments, the package 20 has a second end surface 23 on one side along the second direction B. The distance b between the first adhesive unit 31 near the second end surface 23 and the second end surface 23 is, where 0 mm ≤ b ≤ 5 mm. The second end surface 23 may be a side edge of the packaging bag. In some embodiments, the second end surface 23 is planar and lacks an outwardly extending side seal. In this case, the first edge seal 22 may be fully folded toward the first end surface 21, and the distance b between the first adhesive unit 31 near the second end surface 23 and the second end surface 23 may be 0 mm. This allows the end region of the first edge seal 22 in the second direction B to be bonded to the first end surface 21, reducing the risk of warping. In other embodiments, the packaging bag has a second edge seal 24 formed on the second end surface 23, which is bent toward the second end surface 23. The second edge seal 24 may be a side seal extending outward from the side edge. When the first edge sealing portion 22 is folded toward the first end surface 21, the area of the first edge sealing portion 22 close to the second edge sealing portion 24 cannot be completely folded to the first end surface 21. A triangular area is roughly formed between the second edge sealing portion 24, the first edge sealing portion 22 and the first end surface 21. Figure 2 and Figure 5 At this time, the distance b between the first adhesive unit 31 close to the second end surface 23 and the second end surface 23 is greater than 0 mm and less than 5 mm to prevent the adhesive 30 from being exposed in the triangular area.

[0053] In this way, the embodiment of the present application helps to optimize the setting position of the adhesive 30 by constraining the distance between the first bonding unit 31 and the second end face 23, ensuring that the adhesive 30 can be bonded to the first edge sealing portion 22 and the first end face 21 at the same time, thereby improving the utilization rate of the adhesive 30.

[0054] Please participate Figures 7 to 11In some embodiments, the adhesive member 30 further includes a second adhesive unit 32, which is disposed in the spacing region 34 along the second direction B. The junction between the first edge seal 22 and the first end surface 21 is a first edge 221, and the side of the first edge seal 22 extending beyond the tab 12 is a second edge 222. Along the extension direction of the first edge seal 22, the distance between the first adhesive unit 31 and the second edge 222 is smaller than the distance between the second adhesive unit 32 and the second edge 222, and the distance between the second adhesive unit 32 and the first edge 221 is smaller than the distance between the first adhesive unit 31 and the first edge 221. Consequently, the first adhesive unit 31 is disposed closer to the second edge 222, and the second adhesive unit 32 is disposed closer to the first edge 221.

[0055] The second bonding unit 32 can improve the folding and positioning effect of the first edge sealing portion 22. After the first edge sealing portion 22 is folded toward the first end surface 21, the second bonding unit 32 is closer to the connection between the first edge sealing portion 22 and the first end surface 21 than the first bonding unit 31. Figure 12 and Figure 13 As shown, when the gas inside the packaging bag impacts the first edge seal 22, the first edge seal 22 tends to move away from the first end face 21, thereby generating a force F that overcomes the adhesive force. Because the second adhesive unit 32 is close to the first edge 221, the force arm L of the first edge seal 22 on the second adhesive unit 32 is greater than the force arm L' on the first adhesive unit 31, making the second adhesive unit 32 easier to tear, thereby deforming the first edge seal 22 at the corresponding position, allowing the gas to break through the first edge seal 22 and release pressure. In addition, after the first edge seal 22 is folded toward the first end face 21, a cavity is formed between the first edge seal 22 and the first end face 21. Near the junction of the first edge seal 22 and the first end face 21, the cavity has an enlarged area 101. The second adhesive unit 32 can be positioned approximately in the enlarged area, which helps reduce the adhesive force of the second adhesive unit 32 on the first edge seal 22 and the first end face 21, thereby making the first edge seal 22 more susceptible to deformation.

[0056] In some embodiments, the first adhesive unit 31 and the second adhesive unit 32 may be formed on the surface of the first edge sealing portion 22 by gap coating.

[0057] See also Figure 7 In some embodiments, the first edge seal 22 extends beyond the two tabs 12, two first bonding units 31 are provided corresponding to the two tabs 12, and a second bonding unit 32 is provided between the two first bonding units 31 along the second direction B, with the second bonding unit 32 being close to the first edge 221 of the first edge seal 22. The second bonding unit 32 is located in the middle region 13, and the gas inside the packaging bag pushes up the first edge seal 22 from the position of the second bonding unit 32, facilitating the opening of the first edge seal 22 for pressure relief.

[0058] See also Figure 8 In other embodiments, the first edge seal 22 extends beyond two tabs 12, and multiple first adhesive units 31 and multiple second adhesive units 32 are disposed on the first edge seal 22, with each second adhesive unit 32 disposed between two adjacent first adhesive units 31 along the second direction B. The gas within the packaging bag props up the first edge seal 22 at the location of the second adhesive units 32. It is understood that in other embodiments, the number of tabs 12 may be greater than two, and the number of first adhesive members 30 and second adhesive members 30 may be adjusted accordingly, and this application is not limited thereto.

[0059] In some embodiments, the distance between the first adhesive unit 31 and the second edge 222 is c, and the distance between the second adhesive unit 32 and the second edge 222 is d, where c < d; 0.1 mm ≤ c ≤ 1 mm; and / or 1 mm ≤ d ≤ 2.5 mm. By constraining the position and dimensions of the first adhesive unit 31 and the second adhesive unit 32, the success rate of gas breaking through the first edge seal 22 is increased, thereby improving battery safety.

[0060] See also Figure 9 In some embodiments, the adhesive member 30 further includes a third adhesive unit 33. The third adhesive unit 33 is located between the first adhesive unit 31 and the second adhesive unit 32 along the second direction B. The third adhesive unit 33 connects the adjacent first adhesive unit 31 and the second adhesive unit 32 along the extension direction of the first edge sealing portion 22.

[0061] The first bonding unit 31, the second bonding unit 32, and the third bonding unit 33 form a concave-convex structure on the surface of the first edge seal 22. The provision of the third bonding unit 33 can further enhance the folding and positioning effect of the first edge seal 22. At the same time, the third bonding unit 33 does not block the spacing area 34 between adjacent first bonding units 31, ensuring that the gas inside the packaging bag can push up the first edge seal 22 from the spacing area 34, thereby breaking open the first edge seal 22 for pressure relief.

[0062] In some embodiments, the first edge sealing portion 22 is provided with two tabs 12, two first bonding units 31 are provided corresponding to the two tabs 12, a second bonding unit 32 is provided between the two first bonding units 31 along the second direction B, and two third bonding units 33 are respectively provided at both ends of the second bonding unit 32, and connect the adjacent first bonding units 31 and second bonding units 32 along the extension direction of the first edge sealing portion 22.

[0063] See also Figure 10In some embodiments, the first edge sealing portion 22 is provided with two tabs 12, and a plurality of first bonding units 31 and a plurality of second bonding units 32 are alternately arranged on the first edge sealing portion 22 along the second direction B. There are also a plurality of third bonding units 33. Each third bonding unit 33 is arranged between the first bonding unit 31 and the second bonding unit 32 along the second direction B, and connects adjacent first bonding units 31 and second bonding units 32 along the extension direction of the first edge sealing portion 22.

[0064] See also Figure 11 In other embodiments, the first edge sealing portion 22 is provided with three tabs 12, three first bonding units 31 are provided corresponding to the three tabs 12, and two second bonding units 32 are respectively provided between adjacent first bonding units 31. There are four third bonding units 33, each provided between the first bonding unit 31 and the second bonding unit 32, and connecting adjacent first bonding units 31 and second bonding units 32 along the extension direction of the first edge sealing portion 22. It is understood that in other embodiments, the number of tabs 12 can be more than three, and the number of first bonding units 31, second bonding units 32, and third bonding units 33 can be adjusted accordingly, and the present application is not limited to this.

[0065] See also Figure 14 In some embodiments, the adhesive member 30 includes a second adhesive unit 32 disposed in the spacing region 34 along the second direction B, connecting the second adhesive unit 32 to the adjacent first adhesive unit 31. Along the extension direction of the first edge seal 22, the width of the first adhesive unit 31 is e, and the width of the second adhesive unit 32 is f, where e>f. Thus, along the extension direction of the first edge seal 22, the width f of the second adhesive unit 32 is relatively small, thereby correspondingly reducing the bonding force between the first edge seal 22 and the first end face 21 at this location. This ensures that gas generated within the packaging bag can penetrate the first edge seal 22 at this location, thereby improving the safety performance of the secondary battery 100.

[0066] In some embodiments, along the extension direction of the first edge seal 22, the width of the first adhesive unit 31 is e, where 1 mm ≤ e ≤ 5 mm; and / or the width difference between the first adhesive unit 31 and the second adhesive unit 32 is ef, where 0.2 mm ≤ ef ≤ 1 mm. By constraining the widths of the first and second adhesive units 31, 32, the adhesive force of the second adhesive unit 32 is controlled within a reasonable range, ensuring that gas can effectively break through the first edge seal 22.

[0067] In some embodiments, the length of the second adhesive unit 32 along the second direction B is g, where 1 mm ≤ g ≤ 10 mm. By constraining the length of the second adhesive unit 32, the size of the spacing area 34 between adjacent first adhesive units 31 is constrained, which can keep the weak area of the adhesive 30 within a reasonable range, further improving the success rate of gas breaking through the first edge seal 22 and enhancing the safety and reliability of the battery.

[0068] In some embodiments, the adhesive member 30 is provided with a clearance region 35 located between adjacent first adhesive units 31. Along the extension direction of the first edge seal 22, one side of the clearance region 35 is connected to the second adhesive unit 32. The clearance region 35 may be part of the spacing region 34. Along the extension direction of the first edge seal 22, the outer edge of the second adhesive unit 32 does not extend beyond the outer edge of the first adhesive unit 31, forming an area of alternating strong and weak adhesive force in the adhesive member 30 as a whole. This ensures that the first edge seal 22 is folded and positioned effectively while allowing gas generated within the packaging bag to penetrate the first edge seal 22 through the weak area, reducing the risk of explosion and fire.

[0069] See also Figure 15 In some embodiments, both sides of the air-avoidance region 35 are connected to the second adhesive units 32. Thus, along the extension direction of the first edge-sealing portion 22, empty slots are formed between adjacent second adhesive units 32. This is equivalent to forming a plurality of empty slots spaced along the first direction A on the adhesive member 30. These empty slots constitute weak bonding areas of the adhesive member 30.

[0070] Please refer again Figures 1 to 15 In some embodiments, along the second direction B, the first bonding units 31 are symmetrically distributed with the centerline 14 of the middle region 13 as the central axis. Having the position of the first bonding units 31 roughly correspond to the position of the tabs 12 helps improve the flatness of the folded first edge seal 22, uniformly applies force to the first edge seal 22, and ensures that internal gas can effectively break through the first edge seal 22 from the weak bonding area. In some embodiments of the present application, the centerline of the electrode assembly 10 roughly overlaps with the centerline 14 of the middle region 13 to further improve the uniformity of force on the first edge seal 22 and ensure that gas can effectively break through the first edge seal 22.

[0071] See also Figure 16 The embodiment of the present application further provides an electrical device 200 , comprising an electrical component 201 and the secondary battery 100 described in the above embodiment, wherein the electrical component 201 is electrically connected to the secondary battery 100 .

[0072] The above embodiments are only used to illustrate the technical solutions of the present application and are not intended to limit the present application. Although the present application has been described in detail with reference to the above preferred embodiments, those skilled in the art should understand that modifications or equivalent replacements of the technical solutions of the present application should not depart from the spirit and scope of the technical solutions of the present application.

Claims

1. A secondary battery, characterized in that: include: An electrode assembly, comprising an electrode body and a tab, wherein the tab is electrically connected to the electrode body; A package, wherein the electrode body is disposed in the package, wherein along a first direction, one side of the package has a first end surface and a first edge seal, wherein the first edge seal extends outward from the first end surface, the first edge seal is folded toward the first end surface, and the electrode tab at least partially extends out of the package from the first edge seal; an adhesive member, disposed between the first edge sealing portion and the first end surface, for bonding the first edge sealing portion and the first end surface; The adhesive member includes a plurality of first adhesive units, which are spaced apart along the second direction, and a projection of the tab on the first end surface at least partially overlaps with a projection of the first adhesive unit on the first end surface. The electrode tab includes a first electrode tab and a second electrode tab. Along the second direction, the area between the first electrode tab and the second electrode tab is a middle area, and the area between adjacent first bonding units is a spacing area. The middle area at least partially overlaps with the spacing area. A thickness direction of the secondary battery is a third direction, and the third direction, the first direction, and the second direction are perpendicular to each other.

2. The secondary battery according to claim 1, wherein Along the second direction, the length of the spacing area is a, wherein 3 mm ≤ a ≤ 10 mm.

3. The secondary battery according to claim 1, wherein Along the second direction, one side of the package has a second end surface, and a distance between the first bonding unit close to the second end surface and the second end surface is b, wherein 0 mm ≤ b ≤ 5 mm.

4. The secondary battery according to claim 1, wherein The adhesive member further includes a second adhesive unit, and along the second direction, the second adhesive unit is arranged in the spacing area; The connection between the first edge sealing portion and the first end face is the first edge, and the side of the first edge sealing portion extending out of the pole ear is the second edge. Along the extension direction of the first edge sealing portion, the distance between the first bonding unit and the second edge is smaller than the distance between the second bonding unit and the second edge, and the distance between the second bonding unit and the first edge is smaller than the distance between the first bonding unit and the first edge.

5. The secondary battery according to claim 4, wherein The adhesive member further includes a third adhesive unit, which is located between the first adhesive unit and the second adhesive unit along the second direction; and connects the adjacent first adhesive unit and the second adhesive unit along the extension direction of the first edge sealing portion.

6. The secondary battery according to claim 4, characterized in that The distance between the first bonding unit and the second side is c, and the distance between the second bonding unit and the second side is d, wherein c<d; 0.1mm≤c≤1mm; and / or, 1mm≤d≤2.5mm.

7. The secondary battery according to claim 1, wherein The adhesive member further includes a second adhesive unit, which is arranged in the spacing area along the second direction and is connected to the adjacent first adhesive unit; Along the extension direction of the first edge sealing portion, the width of the first adhesive unit is e, and the width of the second adhesive unit is f, wherein e>f.

8. The secondary battery according to claim 7, wherein: Along the extension direction of the first edge sealing portion, the width of the first bonding unit is e, wherein 1mm≤e≤5mm; and / or, A width difference between the first adhesive unit and the second adhesive unit is ef, where 0.2 mm ≤ ef ≤ 1 mm.

9. The secondary battery according to claim 8, characterized in that Along the second direction, the length of the second bonding unit is g, where 1 mm ≤ g ≤ 10 mm.

10. The secondary battery according to claim 7, wherein The adhesive member is provided with an air avoidance area, which is located between adjacent first adhesive units. Along the extension direction of the first edge sealing portion, one side of the air avoidance area is connected to the second adhesive unit or both sides of the air avoidance area are respectively connected to the second adhesive unit.

11. The secondary battery according to claim 1, wherein Along the second direction, the first bonding units are symmetrically distributed with the center line of the middle area as the center axis.

12. An electrical device, characterized in that: The device comprises an electrical component and the secondary battery according to any one of claims 1 to 11, wherein the electrical component is electrically connected to the secondary battery.

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