Secondary battery and electronic device

Abstract

A secondary battery (100) and an electronic device (1). The secondary battery (100) comprises a shell (10), at least one electrode assembly (20) arranged in the shell (10), and a plurality of first tabs (30). The electrode assembly (20) comprises a first pole piece (21). The plurality of first tabs (30) are respectively connected with the first pole piece (21) and extend out of the first pole piece (21) along a first direction; the secondary battery (100) also includes a first adapter (50) provided in the case (10). The first adapter (50) comprises a first connecting area (51), an adapter area (53), a bending area (54) and a second connecting area (52) which are connected in sequence. The switching area (53) comprises a first edge (531) and a second edge (532) which are arranged adjacently. The first connection area (51) is connected to the first edge (531), the first connection area (51) extends from the first edge (531) in a second direction, and the second direction is perpendicular to the first direction. The bending area (54) is connected to the second edge (532) and is bent relative to the switching area (53) and the second connecting area (52). The transition region (53) and the second connection region (52) overlap when viewed from the first direction. The first connection area (51) is connected to the first tab (30), and the second connection area (52) is connected to the housing (10). The reliability and the service life of the secondary battery (100) are improved.

Description

Secondary batteries and electronic devices Technical Field

[0001] The present application relates to the field of energy storage technology, and in particular to a secondary battery and an electronic device having the secondary battery. Background Art

[0002] Secondary batteries (such as lithium-ion batteries) are widely used in electronic products such as mobile devices, power tools, and electric vehicles. A secondary battery typically consists of a housing, an electrode assembly housed within the housing, tabs connected to the electrode assembly, and an adapter that connects the tabs to the housing.

[0003] However, when the secondary battery is subjected to mechanical abuse (such as falling or collision), the electrode assembly may shake in the shell, thereby pulling on the tab. If the tab is separated from the adapter, the reliability and service life of the secondary battery will be reduced.

[0004] Summary of the Invention

[0005] In view of this, it is necessary to provide a secondary battery and an electronic device having the secondary battery.

[0006] In a first aspect, the present application provides a secondary battery comprising a shell, at least one electrode assembly disposed in the shell, and a plurality of first tabs. The electrode assembly comprises a first pole piece. The plurality of first tabs are respectively connected to the first pole piece and extend out of the first pole piece in a first direction. The secondary battery further comprises a first adapter disposed in the shell. The first adapter comprises a first connection area, a transition area, a bending area, and a second connection area connected in sequence. The transition area comprises a first side and a second side arranged adjacent to each other. The first connection area is connected to the first side and extends from the first side in a second direction perpendicular to the first direction. The bending area is connected to the second side and is bent relative to both the transition area and the second connection area. When viewed from the first direction, the transition area and the second connection area overlap. The first connection area is connected to the first tab, and the second connection area is connected to the shell.

[0007] In this application, the transition area and the second connection area can jointly fill the gap between the housing and the electrode assembly, reducing the shaking of the electrode assembly within the housing when the secondary battery is mechanically abused. Furthermore, even if the electrode assembly shakes within the housing and pulls on the first tab, the transition area connected to the bend area can provide a larger buffer space, reducing the possibility that the first tab will detach from the first adapter, resulting in a decrease in the secondary battery's output voltage or even inability to continue charging and discharging. Therefore, this application can improve the reliability and service life of the secondary battery.

[0008] Based on the first aspect, in some possible implementations, the first electrode tab includes a first segment connected to the first electrode sheet and a second segment connected to the first segment, wherein the second segment is bent relative to the first segment. The plurality of second segments form a first connecting portion. The first connecting region is connected to a surface of the first connecting portion facing the electrode assembly. This facilitates reducing the space occupied by the first electrode tab on one side of the electrode assembly in the first direction, thereby increasing the energy density of the secondary battery.

[0009] Based on the first aspect, in some possible implementations, the plurality of first tabs are divided into N tab groups, where N is a positive integer. Each tab group includes two tab bundles, wherein the first segments of the two tab bundles extend away from each other, and the second segments bend and extend toward each other. By independently bending each tab bundle, the length required for stacking the second segments after the first tabs are bent is reduced, thereby reducing the overall weight and production cost of the secondary battery.

[0010] Based on the first aspect, in some possible implementations, the number of electrode assemblies is one, and the N electrode tab groups are all connected to the first electrode sheet of the electrode assembly.

[0011] Based on the first aspect, in some possible implementations, there are multiple electrode assemblies, and N tab groups are respectively connected to the first pole pieces of the multiple electrode assemblies. By dividing the first tabs contained in the multiple electrode assemblies into an even number of tab bundles and bending each tab bundle independently, the first tabs are bent so that the length required for the second sections to be stacked on each other is shorter, thereby reducing the overall weight and production cost of the secondary battery. In addition, when at least one electrode assembly has a quality problem, the problematic electrode assembly (and other electrode assemblies welded to the electrode assembly) can be removed separately to avoid the risk of all electrode assemblies being scrapped at the same time when the first tabs of all electrode assemblies are bent together.

[0012] Based on the first aspect, in some possible implementations, the first connection region includes N first subareas, each of which is connected to the second segment of a first tab in a tab bundle. The N first subareas correspond one-to-one with the N tab groups, thereby facilitating connection of the first adapter to each tab group.

[0013] Based on the first aspect, in some possible implementations, the first connection region further includes a second partition. The second partition is connected to two adjacent first partitions, and the second partition is connected to the first side. The provision of the second partition helps reduce the resistance of the first partition, thereby reducing internal resistance and improving the charge and discharge efficiency of the secondary battery.

[0014] Based on the first aspect, in some possible implementations, the second segments of the first tabs in the tab bundle are stacked and welded to form a first welded region, thereby improving the connection strength between the second segments. The first connection region is welded to the second segment to form a second welded region, thereby improving the weld strength between the first connection region and the second segment. When viewed from a first direction, the first welded region and the second welded region are separated, thereby reducing the risk of over-welding at the first welded region.

[0015] Based on the first aspect, in some possible implementations, the secondary battery further includes a first adhesive member. The first adhesive member covers and bonds the first welding region and the second welding region. The first adhesive member further extends to a surface of the electrode assembly in a third direction, the third direction being perpendicular to both the first and second directions. The first adhesive member may cover and bond the weld marks of the first and second welding regions, thereby integrally connecting the first tab to the electrode assembly.

[0016] Based on the first aspect, in some possible implementations, there are two first adapters, and the two first adapters are arranged along a third direction that is perpendicular to both the first direction and the second direction. The first partitions of the two first adapters correspond one-to-one with the N tab groups, thereby facilitating connection of the first adapters to each tab group.

[0017] Based on the first aspect, in some possible implementations, the transition areas of the two first transition components are connected, which can further reduce the shaking of the first transition components in the housing during mechanical abuse.

[0018] Based on the first aspect, in some possible implementations, the second connection areas of the two first adapters are connected, which can further reduce the shaking of the first adapters in the housing during mechanical abuse.

[0019] Based on the first aspect, in some possible implementations, the secondary battery is a prismatic battery. The housing includes a first end wall and a second end wall disposed opposite each other in a first direction, a side wall connected between the first end wall and the second end wall, and a first terminal disposed on the first end wall. The first terminal is electrically isolated from the first end wall, and the second connection region is electrically connected to the first terminal. Therefore, the first terminal and the second terminal can exhibit the same electrical polarity as the first and second electrode sheets, respectively, and the first terminal and the second terminal can be used to connect to external components.

[0020] Based on the first aspect, in some possible implementations, the first pole protrudes from the first end wall toward the electrode assembly. The second connection region includes a protruding segment connected to the bent region and a straight segment connected to the protruding segment. The straight segment is fixed to the first pole, and the protruding segment is fixed to the first end wall. Therefore, by fixing the protruding segment to the first end wall, the risk of the first adapter wobbling within the housing during mechanical abuse can be further reduced, and the reliability of the connection between the first pole and the straight segment can be improved.

[0021] Based on the first aspect, in some possible implementations, the protruding section is provided with an opening, and the first end wall is provided with a protrusion, which passes through the opening. This facilitates securing the first adapter to the first end wall, and the protrusion can inhibit the first adapter from shaking in the second direction or the third direction within the housing.

[0022] Based on the first aspect, in some possible implementations, the secondary battery further includes a second adhesive member bonded to a surface of the straight segment facing the electrode assembly. The second adhesive member can cover weld marks between the straight segment and the first electrode post, as well as cutting burrs on the straight segment itself, thereby reducing damage to the electrode assembly caused by such weld marks or burrs during mechanical abuse.

[0023] Based on the first aspect, in some possible implementations, the secondary battery further includes a third adhesive member, the third adhesive member being bonded to a surface of the transition region facing the second connection region. The third adhesive member can further isolate weld marks between the straight segment and the first electrode post, as well as cutting burrs on the straight segment itself, thereby reducing damage to the electrode assembly caused by such weld marks or burrs during mechanical abuse.

[0024] Based on the first aspect, in some possible implementations, along the second direction, the width of the bending zone is W, the width of the transition zone is W1, and the width of the second connection zone is W2, where W is smaller than W1 and W2, making the bending zone easier to bend.

[0025] Based on the first aspect, in some possible implementations, the electrode assembly has a laminated structure and includes a plurality of first electrode sheets, wherein the plurality of first electrode sheets are stacked along a third direction perpendicular to both the first and second directions. The laminated structure is advantageous in reducing the internal resistance of the secondary battery and improving high-rate charge and discharge performance.

[0026] Based on the first aspect, in some possible implementations, the electrode assembly has a wound structure, and a winding center axis of the electrode assembly extends along a first direction. The wound structure is conducive to improving the production efficiency of the secondary battery.

[0027] A second aspect of the present application further provides an electronic device comprising a battery compartment and a secondary battery as described above. The secondary battery is housed in the battery compartment. The electronic device is powered by the secondary battery, and the reliability and service life of the secondary battery are improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0029] FIG1 is a schematic structural diagram of a secondary battery provided in some examples according to one embodiment of the present application.

[0030] FIG. 2 is a cross-sectional view of the secondary battery shown in FIG. 1 along the cutting line II-II in some embodiments.

[0031] FIG3 is a cross-sectional view of the secondary battery shown in FIG1 along the cutting line III-III in some embodiments (the separator is omitted).

[0032] FIG. 4 is a cross-sectional view of the secondary battery shown in FIG. 1 along the cutting line IV-IV in some embodiments.

[0033] FIG. 5 is a cross-sectional view of the secondary battery shown in FIG. 1 along the cutting line VV in some embodiments.

[0034] FIG. 6 is a cross-sectional view of the secondary battery shown in FIG. 1 along the cutting line II-II in some other embodiments.

[0035] FIG7A is a schematic structural diagram of the first adapter and the second adapter in the secondary battery shown in FIG3 when they are in an unfolded state.

[0036] FIG. 7B is a schematic structural diagram of the first adapter in the secondary battery shown in FIG. 3 when viewed along the first direction.

[0037] FIG. 7C is a schematic structural diagram of the first adapter shown in FIG. 7A after being welded to the first tab in some embodiments.

[0038] FIG. 7D is a schematic structural diagram of the first adapter shown in FIG. 7A after being welded to the first tab in some other embodiments.

[0039] FIG. 8 is a cross-sectional view of the secondary battery shown in FIG. 1 along the cutting line VV in some other embodiments.

[0040] FIG. 9 is a schematic structural diagram of the secondary battery shown in FIG. 8 when the first adapter is in an unfolded state in some embodiments.

[0041] FIG. 10 is a schematic structural diagram of the secondary battery shown in FIG. 8 when the first adapter is in an unfolded state in some other embodiments.

[0042] FIG. 11 is a cross-sectional view of the secondary battery shown in FIG. 1 along the cutting line IV-IV in some other embodiments.

[0043] FIG. 12 is a schematic structural diagram of the secondary battery shown in FIG. 11 when the first adapter is in an unfolded state in some embodiments.

[0044] FIG. 13 is a cross-sectional view of the secondary battery shown in FIG. 1 along the cutting line IV-IV in some other embodiments.

[0045] FIG. 14 is a schematic structural diagram of the secondary battery shown in FIG. 13 when the first adapter is in an unfolded state in some embodiments.

[0046] FIG. 15 is a schematic structural diagram of the secondary battery shown in FIG. 13 in some other embodiments when the first adapter is in an unfolded state.

[0047] FIG. 16 is a cross-sectional view of the secondary battery shown in FIG. 1 along the cutting line IV-IV in some embodiments.

[0048] FIG. 17 is a cross-sectional view of the secondary battery shown in FIG. 1 along the cutting line VV in some other embodiments.

[0049] FIG18 is a schematic structural diagram of an electronic device provided in one embodiment of the present application.

[0050] Component Symbols Description Electronic Device 1 Housing 10 First End Wall 11 Second End Wall 12 Side Wall 13 First Post 14 Second Post 15 Electrode Assembly 20 First Pole Sheet 21 Second Pole Sheet 22 Separator 23 First Tab 30 Tab Group 30A Tab Bundle 30B First Segment 31 Second Segment 32 Second Tab 40 First Adapter 50 First Connecting Region 51 Second Connecting Region 52 Connecting Region 53 Bending Region 54 Second Adapter 60 First Adhesive 70 Second Adhesive 80 Third Adhesive 90 Secondary Battery 100 Battery Compartment 101 Protrusion 110 First Opening 111 Second Opening 112 First Current Collector 210 First Active Material Layer 211 Second Current Collector 220 Second Active Material Layer 221 First Connecting Portion 320 First Partition 511 Second Partition 512 Protruding Section 521 Straight Section 522 First Side 531 Second Side 532 Opening 5210 First Direction X Second direction Y Third direction Z First side Z1 Second side Z2 Accommodation space S First welding area S1 Second welding areaS2 Width W, W1, W2 Winding center axis O

[0051] The following specific implementation methods will further illustrate the present application in conjunction with the above-mentioned drawings. DETAILED DESCRIPTION

[0052] The technical solutions in the embodiments of the present application are described clearly and in detail below. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all of the embodiments. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present application. The terms used in the specification of the present application are only for the purpose of describing specific embodiments and are not intended to limit the present application.

[0053] Below, embodiments of the present application will be described in detail. However, the present application may be embodied in many different forms and should not be construed as limited to the exemplary embodiments illustrated herein. Rather, these exemplary embodiments are provided to make the present application thorough and detailed for those skilled in the art.

[0054] In addition, for the sake of brevity and clarity, the size or thickness of various components, layers may be exaggerated in the accompanying drawings. Throughout the text, the same numerical value refers to the same element. As used herein, the terms "and / or" and "and / or" include any and all combinations of one or more related enumerated items. In addition, it should be understood that when element A is referred to as "connecting" element B, element A may be directly connected to element B, or there may be an intermediate element C and element A and element B may be indirectly connected to each other.

[0055] Further, when describing embodiments of the present application, the use of “may” refers to “one or more embodiments of the present application.”

[0056] The technical terms used herein are for the purpose of describing specific embodiments and are not intended to limit this application. As used herein, the singular is intended to include the plural, unless the context clearly indicates otherwise. It should be further understood that the term "comprising", when used in this specification, refers to the presence of the described features, values, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, values, steps, operations, elements, components and / or combinations thereof.

[0057] Spatial related terms, such as "on" etc., can be used herein for convenient description, to describe the relationship between an element or feature and another element (multiple elements) or feature (multiple features) as illustrated in the figure. It should be understood that, in addition to the directions described in the figure, spatial related terms are intended to include different directions of equipment or devices in use or operation. For example, if the equipment in the figure is turned over, the elements described as "above" or "on" other elements or features will be oriented "below" or "below" other elements or features. Therefore, the exemplary term "on" can include the direction above and below. It should be understood that although the terms first, second, third, etc. can be used herein to describe various elements, components, regions, layers and / or parts, these elements, components, regions, layers and / or parts should not be limited by these terms. These terms are used to distinguish an element, component, region, layer or part from another element, component, region, layer or part. Therefore, the first element, component, region, layer or part discussed below can be referred to as the second element, component, region, layer or part, without departing from the teachings of the exemplary embodiments.

[0058] As used herein, "parallel" and "perpendicular" are used to describe an ideal state between two components. In actual production or use, there may be a state between two components that is approximately parallel or perpendicular. For example, in combination with numerical descriptions, parallel can refer to the angle between two straight lines being between ±10°, parallel can also refer to the dihedral angle between two planes being between ±10°, and parallel can also refer to the angle between a straight line and a plane being between ±10°. Perpendicular can refer to the angle between two straight lines being between 90±10°, perpendicular can also refer to the dihedral angle between two planes being between 90±10°, and perpendicular can also refer to the angle between a straight line and a plane being between 90±10°. The two components described as "parallel" or "perpendicular" may not be absolute straight lines or planes, but may be roughly straight lines or planes. From a macroscopic perspective, a component can be considered a "straight line" or "plane" if its overall extension direction is a straight line or plane.

[0059] In this application, the relationship between parameter values ​​that is greater than, less than, or not equal to the design relationship needs to exclude the reasonable error of the measuring equipment.

[0060] Referring to Figures 1 to 5 , one embodiment of the present application provides a secondary battery 100 comprising a housing 10, at least one electrode assembly 20 and an electrolyte (not shown) disposed within the housing 10, a plurality of first electrode tabs 30, and a plurality of second electrode tabs 40. For illustration, assuming one electrode assembly 20, as shown in Figures 2 to 5 , each electrode assembly 20 may be a laminate structure comprising a plurality of first electrode sheets 21, a plurality of second electrode sheets 22, and a plurality of separators 23. In the laminate structure, the first electrode sheets 21 and the second electrode sheets 22 are alternately stacked, with one second electrode sheet 22 provided between each pair of adjacent first electrode sheets 21, and one first electrode sheet 21 provided between each pair of adjacent second electrode sheets 22. Separators 23 are disposed between adjacent first electrode sheets 21 and second electrode sheets 22. Separators 23 are used to prevent direct contact between the first electrode sheets 21 and the second electrode sheets 22, thereby reducing the possibility of a short circuit between the first electrode sheets 21 and the second electrode sheets 22. The first electrode tabs 30 are electrically connected to the first electrode sheet 21 and extend from the first electrode sheet 21 along the first direction X. The second electrode tabs 40 are electrically connected to the second electrode sheet 22 and extend from the second electrode sheet 22 along the first direction X. Referring to FIG. 6 , in other embodiments, the electrode assembly 20 may also be a wound structure, in which case the winding center axis O of the electrode assembly 20 extends along the first direction X.

[0061] As shown in Figures 1 to 6, the shell 10 is made of metal. In some embodiments, the shell 10 includes a first end wall 11 and a second end wall 12 arranged opposite to each other in a first direction X, a side wall 13 connected between the first end wall 11 and the second end wall 12, and a first pole 14 and a second pole 15 respectively provided on the first end wall 11. The first pole 14 and the second pole 15 are both electrically isolated from the first end wall 11. The first end wall 11 and the second end wall 12 can be arranged in parallel. The side wall 13 and the second end wall 12 enclose a storage space S for accommodating the electrode assembly 20 and the electrolyte, and the first end wall 11 covers the storage space S. In some embodiments, the secondary battery 100 is a square shell battery. The side wall 13 and the second end wall 12 can be integrally formed, and the first end wall 11 and the side wall 13 can be welded or clamped to fix. The shell 10 can be made of steel as a whole. For example, the steel shell includes the elements Fe and C. The steel shell may also include one or more of the elements Ni, Co, Al, Mn, Cr, Cu, Mg, Mo, S, Si, Ti, V, Pb, Sb, N, and P. For example, the first end wall 11 is made of steel, and the second end wall 12 and side wall 13 are also made of steel. As shown in FIG3 , the first end wall 11 has a first opening 111 and a second opening 112 spaced apart from each other. The first pole 14 and the second pole 15 can be mounted to the first opening 111 and the second opening 112, respectively, by bonding or riveting.

[0062] Among them, a three-dimensional coordinate system is established based on the mutually perpendicular first direction X, second direction Y and third direction Z. In the description of the embodiment of the present application, the first direction X is the direction in which the first pole ear 30 extends out of the first pole piece 21, and is also the direction from the second end wall 12 to the first end wall 11. The second direction Y is the direction from the first pole column 14 to the second pole column 15. The third direction Z is the stacking direction of the multiple first pole pieces 21. Although the third direction Z is marked with a specific vector direction in Figures 1 to 6 to illustrate the stacking direction of the multiple first pole pieces 21, it can be understood that the opposite direction of the above-mentioned marked direction can also be the stacking direction of the multiple first pole pieces 21. The third direction Z has a first side Z1 and a second side Z2 opposite to the first side Z1.

[0063] As shown in Figures 2 to 6, the first electrode sheet 21 includes a first current collector 210 and a first active material layer 211 stacked in the third direction Z, and the first electrode tab 30 is connected to the first current collector 210. The first electrode sheet 21 can be a positive electrode sheet. Correspondingly, the first current collector 210 can be a positive electrode current collector, and the first active material layer 211 can be a positive electrode active material layer. The second electrode sheet 22 includes a second current collector 220 and a second active material layer 221 stacked, and the second electrode tab 40 is connected to the second current collector 220. The second electrode sheet 22 can be a negative electrode sheet. Correspondingly, the second current collector 220 can be a negative electrode current collector, and the second active material layer 221 can be a negative electrode active material layer.

[0064] The positive electrode current collector may be made of aluminum foil or nickel foil, and the negative electrode current collector may be made of at least one of copper foil, nickel foil or carbon-based current collector. The positive electrode active material layer contains a positive electrode active material, and the positive electrode active material includes a compound that can reversibly embed and deintercalate lithium ions (lithiated intercalation compound). In some embodiments, the positive electrode active material may include a lithium transition metal composite oxide. The lithium transition metal composite oxide contains lithium and at least one element selected from cobalt, manganese and nickel. In some embodiments, the positive electrode active material is selected from lithium cobaltate (LiCoO2), lithium nickel manganese cobalt ternary material (NCM), lithium manganese oxide (LiMn2O4), lithium nickel manganese oxide (LiNi 0.5 Mn 1.5 O4) or at least one of lithium iron phosphate (LiFePO4).

[0065] The negative electrode active material layer contains a negative electrode active material, which is a negative electrode active material known in the art that can reversibly deintercalate active ions, and is not limited in this application. For example, it can be a combination of one or more of graphite, soft carbon, hard carbon, carbon fiber, mesophase carbon microspheres, silicon-based materials, tin-based materials, lithium titanate or other metals that can form alloys with lithium. Among them, graphite can be selected from a combination of one or more of artificial graphite, natural graphite and modified graphite; silicon-based materials can be selected from a combination of one or more of elemental silicon, silicon oxide compounds, silicon-carbon composites, and silicon alloys; tin-based materials can be selected from a combination of one or more of elemental tin, tin oxide compounds, and tin alloys.

[0066] The isolation film 23 includes at least one of polyethylene, polypropylene, polyvinylidene fluoride, polyethylene terephthalate, polyimide, or aramid. For example, the polyethylene includes at least one selected from high-density polyethylene, low-density polyethylene, or ultra-high molecular weight polyethylene. Polyethylene and polypropylene have a good effect on improving short circuits.

[0067] As shown in Figures 3 to 5, the secondary battery 100 also includes a first adapter 50 and a second adapter 60 (the second adapter 60 is shown in Figure 3). The first adapter 50 and the second adapter 60 are both disposed within the housing 10. In the first direction X, the first adapter 50 and the second adapter 60 are both disposed on the side of the electrode assembly 20 facing the first end wall 11. The first adapter 50 is connected to the first electrode tab 30 and the housing 10, respectively, and the second adapter 60 is connected to the second electrode tab 40 and the housing 10, respectively. In some embodiments, the first adapter 50 can be connected to the first electrode 14, and the second adapter 60 can be connected to the second electrode 15. Therefore, the first electrode 14 and the second electrode 15 can have opposite polarities, allowing the secondary battery 100 to power external components (not shown). For example, when the first electrode 21 is a positive electrode and the second electrode 22 is a negative electrode, the first electrode 14 has a positive polarity and the second electrode 15 has a negative polarity. Moreover, when the first adapter 50 connects the first electrode tab 30 to the first electrode post 14 and the second adapter 60 connects the second electrode tab 40 to the second electrode post 15 , the first electrode tab 30 and the second electrode tab 40 are guided to the same end of the electrode assembly 20 by the two adapters.

[0068] Please refer to Figures 3, 4, 5, 7A, and 7B. Figure 7A is a schematic diagram of the structure of the first adapter 50 when it is in the unfolded state, and Figure 7B is a schematic diagram of the structure of the first adapter 50 when it is bent and viewed along the first direction X. The first adapter 50 includes a first connection area 51, a transition area 53, a bending area 54, and a second connection area 52, which are connected in sequence. The transition area 53 can be roughly square and include a first side 531 and a second side 532 disposed adjacent to each other. The first connection area 51 is connected to the first side 531. The connection area 51 can extend from the first side 531 along the second direction Y. The bending area 54 is connected to the second side 532 and is bent relative to both the transition area 53 and the second connection area 52. As shown in Figure 7B, when viewed from the first direction X, the transition area 53 and the second connection area 52 overlap. Although FIG7B shows that a portion of the transition region 53 is exposed from the second connection region 52, in other embodiments, the second connection region 52 may completely cover the transition region 53 when viewed from the first direction X. As shown in FIG4 and FIG5 , when viewed from the second direction Y, the first adapter 50 is generally U-shaped. The first connection region 51 is connected to the first tab 30. For example, the first connection region 51 may be welded to the first tab 30 to improve connection strength and reliability. The second connection region 52 is connected to the housing 10. For example, the second connection region 52 may be welded to the first pole 14 to improve connection strength and reliability. The first adapter 50 may be made of one of aluminum, nickel, copper, steel, or nickel-plated copper. The second adapter 60 may be made of one of aluminum, nickel, copper, steel, or nickel-plated copper. The first adapter 50 may be a one-piece structure, where the first connection region 51, transition region 53, bending region 54, and second connection region 52 are integrally connected. In other embodiments, the first connection area 51 , the transition area 53 , the bending area 54 , and the second connection area 52 may also be connected as one by welding or other means.

[0069] As shown in Figures 7A and 7B, in some embodiments, the first adapter 50 may include at least two bending regions 54 spaced apart along the extension direction of the second edge 532. Each bending region 54 is connected to the second edge 532 and bends relative to both the transition region 53 and the second connection region 52. Providing at least two bending regions 54 improves the connection strength between the transition region 53 and the second connection region 52 while also making the bending regions 54 themselves easier to bend. In some embodiments, along the alignment direction of the transition region 53 and the first connection region 51 (which, when the first adapter 50 is installed in the housing 10, is referred to as the second direction Y), the bending regions 54 have a width W, the transition region 53 has a width W1, and the second connection region 52 has a width W2. W is smaller than both W1 and W2, thereby making the bending regions 54 easier to bend. When there are at least two bending regions 54, the width W of the bending regions 54 refers to the sum of the widths of all bending regions 54 and the widths of the gaps between adjacent bending regions 54. The width W1 of the transition region 53 may be the same as or different from the width W2 of the second connection region 52, and this application does not impose any limitation thereto.

[0070] Furthermore, as shown in FIG. 3 and FIG. 7A , the second adapter 60 may be provided with a structure similar to that of the first adapter 50 , which will not be described in detail in this application.

[0071] When assembling the secondary battery 100, the electrode assembly 20 with the first and second electrode tabs 30, 40 can be placed within the accommodation space S enclosed by the second end wall 12 and side wall 13. A first adapter 50 and a second adapter 60 are initially deployed (see FIG. 7A ). The first adapter 50 and the second adapter 60 are placed side by side on the side of the electrode assembly 20 with the first and second electrode tabs 30, 40. The first connection region 51 of the first adapter 50 and the first connection region (not shown) of the second adapter 60 are welded to the first and second electrode tabs 30, 40, respectively. Then, the first end wall 11 with the first and second electrode posts 14, 15 is placed on the side of the first adapter 50 and the second adapter 60 facing the electrode assembly 20. The second connection region 52 of the first adapter 50 is welded to the first electrode post 14, and the second connection region (not shown) of the second adapter 60 is welded to the second electrode post 15. Then, the bending area 54 of the first adapter 50 and the bending area of ​​the second adapter 60 (not shown) are bent around the second direction Y at the same time, so that the first end wall 11 is turned over to the top of the transfer area 53. At this time, when viewed from the first direction X, the second connection area 52 connected to the first pole 14 and the transfer area 53 overlap. Then, the first end wall 11 is fixed to the side wall 13 to complete the assembly of the secondary battery 100. Among them, if the welding of the tab and the adapter is called the first welding, and the welding of the pole and the adapter is called the second welding, by setting the second connection area 52 to be connected to the second side 532 of the transfer area 53 through the bending area 54, the first end wall 11 can be directly turned over to the top of the transfer area 53 after the above two weldings, thereby facilitating assembly. It can be understood that the above assembly steps are only examples, and the assembly steps of the present application are not limited thereto.

[0072] In the secondary battery 100 of the present application, the bending region 54 of the first adapter 50 is bent relative to both the adapter region 53 and the second connection region 52, so that when viewed from the first direction X, the adapter region 53 and the second connection region 52 overlap. The adapter region 53 and the second connection region 52 can jointly fill the gap between the first end wall 11 and the electrode assembly 20, reducing the shaking of the electrode assembly 20 in the housing 10 when the secondary battery 100 is mechanically abused. Furthermore, even if the electrode assembly 20 shakes in the housing 10 and pulls the first tab 30, the adapter region 53 connected to the bending region 54 can provide a larger buffer space, reducing the possibility that the first tab will detach from the first adapter 50, resulting in a decrease in the output voltage of the secondary battery 100 or even an inability to continue charging and discharging. Therefore, the present application can improve the reliability and service life of the secondary battery 100.

[0073] As shown in Figures 4 and 5, in some embodiments, the first electrode tab 30 is bent. The first electrode tab 30 includes a first segment 31 connected to the first electrode sheet 21 and a second segment 32 connected to the first segment 31. The second segment 32 is bent relative to the first segment 31. By bending the first electrode tab 30, the space occupied by the first electrode tab 30 on one side of the electrode assembly 20 in the first direction X is reduced, thereby improving the energy density of the secondary battery 100. The plurality of second segments 32 collectively form a first connecting portion 320, and the first connecting region 51 is connected to the surface of the first connecting portion 320 facing the electrode assembly 20. Although Figure 4 shows that the first connecting portion 320 is connected to the transition region 53, it is understood that since the first connecting region 51 in Figure 4 is actually located behind the transition region 53, the first connecting portion 320 is actually connected to the first connecting region 51 located behind the transition region 53.

[0074] In some embodiments, the plurality of first pole tabs 30 are divided into N pole tab groups 30A, where N is a positive integer. When the number of electrode assemblies 20 in this embodiment is one, the N pole tab groups 30A are all connected to the first pole piece 21 of the electrode assembly 20. Each pole tab group 30A includes two pole tab bundles 30B, that is, the plurality of first pole tabs 30 are divided into 2N pole tab bundles 30B, that is, an even number of pole tab bundles 30B. For example, as shown in Figures 4 and 5, when N=1, the plurality of first pole tabs 30 are divided into two pole tab bundles 30B; as shown in Figure 8, when N=2, the plurality of first pole tabs 30 are divided into four pole tab bundles 30B. Each pole tab bundle 30B includes at least one first pole tab 30.

[0075] As shown in Figures 4, 5, and 8, in each tab group 30A, the first segments 31 of the two tab bundles 30B extend away from each other, while the second segments 32 extend toward each other, forming a generally U-shaped structure. The second segments 32 of each tab bundle 30B are stacked one on top of the other, thereby facilitating simultaneous electrical connection between the first connection region 51 and all second segments 32 in each tab bundle 30B. In some embodiments, the first tabs 30 in each tab bundle 30B are bent to form a generally U-shaped structure. When the tab bundle 30B includes multiple first tabs 30, the tab bundle 30B has an innermost layer and an outermost layer. The innermost layer of the tab bundle 30B refers to the first tab 30 in the tab bundle 30B connected to the first connection region 51, while the outermost layer of the tab bundle 30B refers to the first tab 30 in the tab bundle 30B that is farthest from the first connection region 51 along the stacking direction. Compared to a solution in which all first tabs 30 are bent together (e.g., all first tabs 30 are first extended toward the first side Z1 and then toward the second side Z2), by dividing the plurality of first tabs 30 into an even number of tab bundles 30B and independently bending each tab bundle 30B, the length required to stack the second segments 32 after the first tabs 30 are bent is reduced. This is particularly true when the electrode assembly 20 is thick in the third direction Z (in which case the required length of the first tabs 30 is greater when all first tabs 30 are bent together). This significantly reduces the length required to bend the first tabs 30, thereby reducing the overall weight and production cost of the secondary battery 100. Furthermore, to reduce the length required to bend the second tabs 40, the plurality of second tabs 40 can also be divided into an even number of tab bundles. The manner in which the plurality of first tabs 30 are divided can be the same as or different from the manner in which the plurality of second tabs 40 are divided. In other embodiments, the plurality of first tabs 30 may not be grouped. At this time, all first tabs 30 are bent together (eg, all first tabs 30 first extend toward the first side Z1 and then toward the second side Z2 ) and welded to the first connection region 51 , thereby reducing welding times and simplifying the manufacturing process.

[0076] As shown in Figures 5 to 7B, in some embodiments, the first connection area 51 includes N first partitions 511. The N first partitions 511 correspond one-to-one to the N tab groups 30A. For example, when the plurality of first tabs 30 are divided into one tab group 30A (i.e., N=1), the first connection area 51 includes only one first partition 511. As shown in Figures 8 and 9, when the plurality of first tabs 30 are divided into two tab groups 30A (i.e., N=2), the first connection area 51 includes two first partitions 511. Each first partition 511 is connected to the second segment 32 of the two tab bundles 30B of one tab group 30A. The first partition 511 and the transition area 53 can both be sheet-like structures, with the plane where the first partition 511 is located extending along the second direction Y and the third direction Z, and the plane where the transition area 53 is located extending along the second direction Y and the third direction Z.

[0077] Referring to FIG. 10 , when there are more than one first partition 511, the first connection region 51 may further include N second partitions 512, each second partition 512 being connected to the first side 531. Each second partition 512 is also connected to two adjacent first partitions 511. The provision of the second partitions 512 helps reduce the resistance of the first partition 511, thereby reducing the internal resistance and improving the charge and discharge efficiency of the secondary battery 100.

[0078] As shown in Figures 11 and 12, in other embodiments, the number of first adapters 50 can also be two, and the two first adapters 50 are arranged along the third direction Z. The structures of the two first adapters 50 can be roughly the same. When the first connection area 51 of each first adapter 50 includes only one first partition 511, the two first adapters 50 have two first partitions 511 in total. At this time, similar to the structure of Figure 8, it can be applied to the case where multiple first tabs 30 are divided into two tab groups 30A (i.e., N=2), and each first partition 511 is connected to the second section 32 of the two tab bundles 30B of one tab group 30A. Among them, the two first adapters 50 can respectively fill the gaps on both sides of the first pole 14 in the third direction Z, reducing the impact of the first adapter 50 on the energy density of the secondary battery 100. It is understood that the first connection region 51 of at least one first adapter 50 may also include two first partitions 511. In this case, the two first adapters 50 may have more first partitions 511, making it applicable to situations where the plurality of first tabs 30 are divided into more tab groups 30A (e.g., N>2). The two first adapters 50 may be spaced apart in the third direction Z.

[0079] Alternatively, two first adapters 50 may be connected in the third direction Z. For example, as shown in Figures 13 and 14 , the second connection regions 52 of the two first adapters 50 are connected. Alternatively, as shown in Figure 15 , the connection regions 53 of the two first adapters 50 may be connected. By connecting the two first adapters 50 in the third direction Z, the shaking of the first adapters 50 within the housing 10 during mechanical abuse can be further reduced.

[0080] Figures 7C and 7D show top views of the first tab 30 being bent and the second segment 32 being welded to the first adapter 50. In some embodiments, the second segments 32 of the first tab 30 in each tab bundle 30B are stacked and welded to form a first weld region S1, thereby improving the connection strength between the second segments 32. The first connection region 51 and the second segment 32 are welded to form a second weld region S2, thereby improving the welding strength between the first connection region 51 and the second segment 32. When manufacturing the secondary battery 100, each tab bundle 30B can be bent using a welding head (not shown) to stack the second segments 32. The second segments 32 of each tab bundle 30B are then pre-welded to improve the connection strength between the second segments 32. Subsequently, the first adapter 50 is placed on the side of the second segment 32 facing the electrode assembly 20, and the first connection region 51 of the first adapter 50 is welded to the second segment 32 using a welding head. The pre-welding and fixing of the second section 32 facilitates the connection between the first connection region 51 and the second section 32 of each first tab 30 of the tab bundle 30B.

[0081] The two tab bundles 30B in a tab group 30A can contain the same number of first tabs 30. This allows the second segments 32 of each tab bundle 30B to be welded using the same welding parameters (e.g., welding time, welding temperature, etc.). This eliminates the need for frequent parameter adjustments when welding different tab bundles 30B, simplifies the manufacturing process, and improves the uniformity of welding quality. Furthermore, this also helps improve the flatness of the structure within the housing 10. In other embodiments, the two tab bundles 30B in a tab group 30A can contain different numbers of first tabs 30.

[0082] As shown in FIG7C , in some embodiments, the first welding region S1 and the second welding region S2 do not overlap, i.e., are separated, when viewed from the first direction X, thereby reducing the risk of over-welding at the first welding region S1. As shown in FIG7D , in other embodiments, the first welding region S1 and the second welding region S2 may overlap when viewed from the first direction X, thereby improving the stability of the weld between the second segments 32 at the first welding region S1.

[0083] As shown in Figures 3 to 5, in some embodiments, the first electrode 14 protrudes from the first end wall 11 toward the electrode assembly 20 to facilitate connection of the first electrode 14 to the second connection region 52. The second connection region 52 includes a protruding section 521 connected to the bend region 54 and a straight section 522 connected to the protruding section 521. The protruding section 521 is arranged to protrude away from the electrode assembly 20 compared to the straight section 522. The straight section 522 is fixed to the portion of the first electrode 14 protruding from the first end wall 11. For example, the straight section 522 can be welded to the portion of the first electrode 14 protruding from the first end wall 11. The protruding section 521 is fixed to the first end wall 11. By fixing the protruding section 521 to the first end wall 11, the risk of the first adapter 50 shaking within the housing 10 during mechanical abuse can be further reduced, and the connection reliability between the first electrode 14 and the straight section 522 can be improved. Furthermore, the shape of the protruding section 521 is also conducive to its fixation with the first end wall 11 .

[0084] Furthermore, the protruding section 521 may be provided with an opening 5210, and correspondingly, the first end wall 11 may be provided with a protrusion 110, protrusion 110 being provided protruding toward the electrode assembly 20. Protrusion 110 passes through the opening 5210, thereby facilitating the fixation of the first adapter 50 to the first end wall 11. Protrusion 110 can also prevent the first adapter 50 from shaking within the housing 10 along the second direction Y or the third direction Z. Furthermore, protrusion 110 can be fixed within the opening 5210 by interference fit, bonding, welding, or the like, thereby further firmly fixing the second connection region 52 of the first adapter 50 to the first end wall 11.

[0085] As shown in FIG16 , in some embodiments, the secondary battery 100 further includes a first adhesive member 70. In the first direction X, at least a portion of the first adhesive member 70 is disposed on the side of the first connection portion 320 facing away from the electrode assembly 20. This portion of the first adhesive member 70 can cover the weld marks of the first and second weld areas S1, S2, and any trimming burrs on the first tab 30 itself, thereby minimizing damage to the housing 10 caused by these weld marks or burrs. The first adhesive member 70 can also extend to two opposing surfaces of the electrode assembly 20 in the third direction Z, thereby integrally connecting the first tab 30 to the electrode assembly 20. The first adhesive member 70 can be a single-sided adhesive tape comprising an insulating material, which can be selected from at least one of polypropylene, polyethylene, polyvinylidene fluoride, vinylidene fluoride-hexafluoropropylene copolymer, polymethyl methacrylate, or polyethylene glycol. In other embodiments, the first adhesive member 70 can also be a ceramic coating.

[0086] The secondary battery 100 may also include a second adhesive 80. In the first direction X, the second adhesive 80 is disposed on the surface of the straight section 522 facing the electrode assembly 20. The second adhesive 80 adheres to the surface of the straight section 522 facing the electrode assembly 20. The second adhesive 80 can cover the weld marks between the straight section 522 and the first electrode post 14, as well as any cutting burrs on the straight section 522 itself, thereby reducing damage to the electrode assembly 20 caused by these weld marks or burrs during mechanical abuse. The second adhesive 80 may be a single-sided adhesive comprising an insulating material, which may be selected from at least one of polypropylene, polyethylene, polyvinylidene fluoride, vinylidene fluoride-hexafluoropropylene copolymer, polymethyl methacrylate, or polyethylene glycol. In other embodiments, the second adhesive 80 may also be a ceramic coating. This reduces the risk of weld marks piercing the first section 31 of the first electrode tab 30, thereby reducing the risk of the first electrode tab 30 fracturing during mechanical abuse.

[0087] The secondary battery 100 may further include a third adhesive 90. In the first direction X, the third adhesive 90 is provided on the surface of the transition area 53 facing the second connection area 52. The third adhesive 90 is bonded to the surface of the transition area 53 facing the second connection area 52. The third adhesive 90 can further isolate the weld marks between the straight section 522 and the first pole 14 and the cutting burrs of the straight section 522 itself, thereby reducing the damage caused to the electrode assembly 20 by the above-mentioned weld marks or burrs during mechanical abuse. Among them, the third adhesive 90 can be a single-sided adhesive containing an insulating material, and the above-mentioned insulating material can be selected from at least one of polypropylene, polyethylene, polyvinylidene fluoride, vinylidene fluoride-hexafluoropropylene copolymer, polymethyl methacrylate or polyethylene glycol. In other embodiments, the third adhesive 90 can also be a ceramic coating.

[0088] Please refer to Figure 17. In other embodiments, there are multiple electrode assemblies 20. The multiple electrode assemblies 20 are connected in parallel or in series, thereby increasing the supply voltage of the secondary battery 100. At this time, N tab groups 30A are respectively connected to the first pole pieces 21 of the multiple electrode assemblies 20, and each tab group 30A includes two tab bundles 30B. That is, this embodiment divides the first tabs 30 contained in the multiple electrode assemblies 20 into an even number of tab bundles 30B and each tab bundle 30B is bent independently. In this way, after the first tab 30 is bent, the length required for the second section 32 to be stacked on each other is shorter. Especially when the thickness of the electrode assembly 20 in the first direction X is large, this embodiment can significantly reduce the length required for the first tab 30 to bend, thereby reducing the overall weight and production cost of the secondary battery 100. In addition, when at least one electrode assembly 20 has a quality problem, the problematic electrode assembly 20 (and other electrode assemblies 20 welded to the electrode assembly 20) can be removed separately to avoid the risk of all electrode assemblies 20 being scrapped simultaneously when the first tabs 30 of all electrode assemblies 20 are bent at the same time. Multiple electrode assemblies 20 can be stacked in the first direction X.

[0089] The secondary battery 100 of the present application may be a lithium secondary battery, including a lithium metal secondary battery, a lithium ion secondary battery, a lithium polymer secondary battery, and a lithium ion polymer secondary battery.

[0090] Referring to FIG. 18 , one embodiment of the present application further provides an electronic device 1 comprising a battery compartment 101 and a secondary battery 100 housed in the battery compartment 101 . The electronic device 1 is powered by the secondary battery 100 , and the reliability and service life of the secondary battery 100 are improved. In some embodiments, the electronic device 1 of the present application may be, but is not limited to, a laptop computer, a pen-type computer, a mobile computer, an e-book player, a portable phone, a portable fax machine, a portable copier, a portable printer, a head-mounted stereo headset, a video recorder, an LCD television, a portable cleaner, a portable CD player, a mini-disc, a transceiver, an electronic notepad, a calculator, a memory card, a portable recorder, a radio, a backup power supply, a motor, a car, a motorcycle, a power-assisted bicycle, a bicycle, a lighting fixture, a toy, a game console, a clock, an electric tool, a flashlight, a camera, a large household battery, and a lithium-ion capacitor, etc.

[0091] The above disclosure is only a preferred embodiment of the present application, and certainly cannot be used to limit the present application. Therefore, equivalent changes made based on the present application are still within the scope covered by the present application.

Claims

1. A secondary battery (100), comprising a housing (10), at least one electrode assembly (20) disposed in the housing (10), and a plurality of first pole tabs (30), wherein the electrode assembly (20) comprises a first pole piece (21), and the plurality of first pole tabs (30) are respectively connected to the first pole piece (21) and extend out of the first pole piece (21) along a first direction (X), wherein: The secondary battery (100) further comprises a first adapter (50) disposed in the housing (10), the first adapter (50) comprising a first connection area (51), a transfer area (53), a bending area (54) and a second connection area (52) connected in sequence, the transfer area (53) comprising a first side (531) and a second side (532) disposed adjacent to each other, the first connection area (51) being connected to the first side (531), the first connection area (51) extending from the first side (531) along a second direction (Y), the second direction (Y) being perpendicular to the first direction (X), the bending area (54) being connected to the second side (532) and being bent relative to both the transfer area (53) and the second connection area (52), and when viewed from the first direction (X), the transfer area (53) and the second connection area (52) are overlapped; The first connection area (51) is connected to the first tab (30), and the second connection area (52) is connected to the housing (10).

2. The secondary battery (100) according to claim 1, wherein: The first electrode tab (30) includes a first section (31) connected to the first electrode sheet (21) and a second section (32) connected to the first section (31); the second section (32) is bent relative to the first section (31); a plurality of second sections (32) form a first connecting portion (320); and the first connecting area (51) is connected to the surface of the first connecting portion (320) facing the electrode assembly (20).

3. The secondary battery (100) according to claim 2, wherein: The plurality of first tabs (30) are divided into N tab groups (30A), where N is a positive integer. Each of the tab groups (30A) includes two tab bundles (30B). In the two tab bundles, the first segments (31) extend in directions away from each other, and the second segments (32) extend in directions approaching each other.

4. The secondary battery (100) according to claim 3, wherein: The number of the electrode assembly (20) is one, and the N electrode tab groups (30A) are all connected to the first electrode piece (21) of the electrode assembly (20).

5. The secondary battery (100) according to claim 3, wherein: There are multiple electrode assemblies (20), and the N electrode tab groups (30A) are respectively connected to the first electrode sheets (21) of the multiple electrode assemblies (20).

6. The secondary battery (100) according to any one of claims 3 to 5, wherein: The first connection area (51) includes N first partitions (511), and each first partition (511) is connected to the second section (32) of the first tab (30) in the tab bundle (30B).

7. The secondary battery (100) according to claim 6, wherein: The first connection area (51) includes a second partition (512), the second partition (512) is connected to two adjacent first partitions (511), and the second partition (512) is connected to the first side (531).

8. The secondary battery (100) according to claim 6 or 7, wherein: The second sections (32) of the first tabs (30) in the tab bundle (30B) are stacked and welded to form a first welding area (S1), and the first connection area (51) and the second section (32) are welded to form a second welding area (S2). When viewed from the first direction (X), the first welding area (S1) and the second welding area (S2) are separated.

9. The secondary battery (100) according to claim 8, wherein: The secondary battery (100) further includes a first adhesive member (70), the first adhesive member (70) covering and bonding the first welding area (S1) and the second welding area (S2), the first adhesive member (70) also extending to the surface of the electrode assembly (20) in a third direction (Z), the third direction (Z) being perpendicular to both the first direction (X) and the second direction (Y).

10. The secondary battery (100) according to any one of claims 1 to 9, wherein: The number of the first adapters (50) is two, and the two first adapters (50) are arranged along a third direction (Z), and the third direction (X) is perpendicular to both the first direction (X) and the second direction (Y).

11. The secondary battery (100) according to claim 10, wherein: The transition areas (53) of the two first transition pieces (50) are connected.

12. The secondary battery (100) according to claim 10, wherein: The second connection areas (52) of the two first adapters (50) are connected.

13. The secondary battery (100) according to any one of claims 1 to 12, wherein: The secondary battery (100) is a square shell battery, and the shell (10) includes a first end wall (11) and a second end wall (12) arranged opposite to each other in the first direction (X), a side wall (13) connected between the first end wall (11) and the second end wall (12), and a first pole (14) provided on the first end wall (11), wherein the first pole (14) is electrically isolated from the first end wall (11), and the second connection area (52) is electrically connected to the first pole (14).

14. The secondary battery (100) according to claim 13, wherein: The first pole (14) protrudes from the first end wall (11) toward the electrode assembly (20), and the second connection area (52) includes a protruding section (521) connected to the bending area (54) and a straight section (522) connected to the protruding section, the straight section (522) is fixed to the first pole (14), and the protruding section (521) is fixed to the first end wall (11).

15. The secondary battery (100) according to claim 14, wherein: The protruding section (521) is provided with an opening (5210), and the first end wall (11) is provided with a protrusion (110), and the protrusion (110) passes through the opening (5210).

16. The secondary battery (100) according to claim 14, wherein: The secondary battery (100) further includes a second adhesive member (80), the second adhesive member (80) being bonded to the surface of the straight section (522) facing the electrode assembly (20).

17. The secondary battery (100) according to claim 16, wherein: The secondary battery (100) further includes a third adhesive member (90), wherein the third adhesive member (90) is bonded to the surface of the transfer area (53) facing the second connection area (52).

18. The secondary battery (100) according to any one of claims 1 to 17, wherein: Along the second direction (Y), the width of the bending area (54) is W, the width of the transition area (53) is W1, and the width of the second connection area (52) is W2, and W is smaller than W1 and W2.

19. The secondary battery (100) according to any one of claims 1 to 18, wherein: The electrode assembly (20) satisfies one of the following conditions: (1) The electrode assembly (20) is a laminated structure and includes a plurality of the first electrode sheets (21), wherein the plurality of the first electrode sheets (21) are stacked along a third direction (Z), and the third direction (Z) is perpendicular to both the first direction (X) and the second direction (Y); (2) The electrode assembly (20) is a wound structure, and the winding center axis (O) of the electrode assembly (20) extends along the first direction (X).

20. An electronic device (1), comprising a battery compartment (101), wherein: The electronic device (1) further comprises a secondary battery (100) according to any one of claims 1 to 19, and the secondary battery (100) is accommodated in the battery compartment (101).

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