Battery

Abstract

The utility model provides a battery. The battery comprises a shell, a roll core and a bonding piece, the roll core is located in the shell, and the bonding piece is arranged between the winding ending position of the roll core and the shell. And the bonding force F1 between the bonding piece and the roll core is smaller than the bonding force F2 between the bonding piece and the shell, so that the problem that the pole piece is easy to break in the charging and discharging process of the battery is effectively solved while the processes of roll core forming, shell entering and the like are smoothly carried out.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, in particular to a battery. Background Art

[0002] Currently, lithium-ion batteries are widely used not only in portable electronic devices such as mobile phones and laptops, but also in electric devices such as electric vehicles and electric bicycles.

[0003] The core component of a lithium-ion battery is the battery cell, which includes a positive electrode sheet, a negative electrode sheet, and a separator disposed between the positive and negative electrodes. The positive electrode sheet, separator, and negative electrode sheet are stacked and wound to form a core. However, the electrodes in related art are prone to breakage during battery charging and discharging. Utility Model Content

[0004] In view of this, the embodiments of the present invention are directed to providing a battery to improve the problem that the electrode is easily broken during the battery charging and discharging process.

[0005] The utility model provides a battery, comprising a shell, a winding core and an adhesive member;

[0006] The winding core is located in the shell, and the adhesive member is provided between the winding end of the winding core and the shell;

[0007] The adhesive force F1 between the adhesive member and the winding core is smaller than the adhesive force F2 between the adhesive member and the shell.

[0008] Optionally, the adhesive force F1 between the adhesive member and the winding core satisfies: 0.05 N / m≤F1≤6 N / m;

[0009] and / or, the bonding force F2 between the adhesive member and the housing satisfies: 20 N / m≤F2≤39 N / m;

[0010] And / or, the adhesive force F1 between the adhesive member and the winding core, and the adhesive force F2 between the adhesive member and the shell satisfy: 2.5%≤F1 / F2≤30%.

[0011] Optionally, the adhesive member includes a substrate layer, a first adhesive layer and a second adhesive layer;

[0012] The first adhesive layer is provided on a side of the substrate layer facing the winding core, and the first adhesive layer is bonded to the winding end of the winding core;

[0013] The second adhesive layer is disposed on a side of the base material layer facing the housing, and the second adhesive layer is bonded to the housing.

[0014] Optionally, the material of the first adhesive layer is selected from at least one of styrene-butadiene rubber, polyisobutylene, polyethylene phenylene ether, polypropylene, polyacrylate, styrene-butadiene ternary block copolymer, and styrene-isoprene-styrene ternary block copolymer;

[0015] And / or, the material of the second adhesive layer is at least one selected from styrene-isoprene copolymer, linear triblock copolymer, hydrogenated styrene-isoprene-styrene block copolymer, and epoxidized styrene-butadiene-styrene block copolymer.

[0016] Optionally, along the first direction, the thickness d1 of the first adhesive layer satisfies: 3 μm≤d1≤6 μm;

[0017] and / or, along the first direction, the thickness d3 of the second adhesive layer and the thickness d1 of the first adhesive layer satisfy: 2d1≤d3≤5d1;

[0018] and / or, along the first direction, the sum of the thickness d1 of the first adhesive layer and the thickness d3 of the second adhesive layer satisfies: d1+d3≥20 μm;

[0019] And / or, along the first direction, the thickness d2 of the substrate layer satisfies: 5 μm≤d2≤12 μm.

[0020] Optionally, the projected area of ​​the first adhesive layer on the substrate layer is not larger than the surface area of ​​the substrate layer on a side facing the first adhesive layer;

[0021] And / or, the first adhesive layer includes at least two adhesive portions, and the at least two adhesive portions are arranged at intervals on the base material layer;

[0022] At least two of the adhesive portions are arranged in an array on the substrate layer; or, at least two of the adhesive portions are arranged in a grid-like staggered manner on the substrate layer; or, at least two of the adhesive portions are arranged parallel to each other.

[0023] Optionally, the second adhesive layer is further doped with a tackifier.

[0024] Optionally, along the first direction, the total thickness D of the adhesive member satisfies: 15 μm≤D≤35 μm;

[0025] And / or, along the second direction, the width h of the adhesive member satisfies: 10 mm ≤ h ≤ 35 mm;

[0026] And / or, along the third direction, the length L of the adhesive member satisfies: 10 mm ≤ L ≤ H, wherein H is the length of the winding core along the third direction.

[0027] Optionally, the winding core includes a straight area and bending areas located at both ends of the straight area, the winding end of the winding core is located in the straight area, and the adhesive is arranged between the straight area and the shell.

[0028] Optionally, the winding core includes a positive electrode sheet, a negative electrode sheet, and a separator disposed between the positive electrode sheet and the negative electrode sheet, and the positive electrode sheet, the separator, and the negative electrode sheet are stacked and wound to form the winding core;

[0029] The winding end of the core is the empty foil area of ​​the positive electrode sheet, and the adhesive is arranged between the empty foil area of ​​the positive electrode sheet and the shell; or the winding end of the core is the diaphragm, and the adhesive is arranged between the diaphragm and the shell.

[0030] The battery provided by the present invention provides an adhesive member between the winding end of the core and the casing, thereby ensuring that the bonding force F1 between the adhesive member and the core is smaller than the bonding force F2 between the adhesive member and the casing. Since the adhesive member can adhere to the winding end of the core, it can prevent the core from loosening before it is inserted into the casing, facilitating smooth core forming and casing insertion processes during production, thereby improving battery production efficiency to a certain extent. Furthermore, since the adhesive member can also adhere to the casing, and the bonding force F1 between the adhesive member and the core is smaller than the bonding force F2 between the adhesive member and the casing, the bonding force F1 between the adhesive member and the core is relatively small. This arrangement makes it possible for the adhesive force F1 between the adhesive and the winding core to be relatively small. Therefore, when the winding core expands during the charging and discharging process and the electrode is subjected to an outward expansion force, the adhesive is subjected to the outward expansion and squeezing of the winding core, and the binding force of the adhesive on the winding end is easily invalidated. For example, the adhesive is easily separated from the winding core, allowing the electrode to expand outward, thereby alleviating and releasing the expansion force of the electrode, thereby effectively improving the problem of the electrode being easily broken during the charging and discharging process of the battery and ensuring the normal use of the battery.

[0031] At the same time, since the bonding force F1 between the adhesive and the core is smaller than the bonding force F2 between the adhesive and the shell, the bonding reliability between the adhesive and the shell is guaranteed, thereby preventing the adhesive from moving around in the shell and squeezing the core to a certain extent. Especially after the adhesive is separated from the core, it can prevent the adhesive from moving around, which may cause deformation of the core, etc., thereby providing good protection for the core and ensuring the normal use of the battery.

[0032] That is to say, through the above-mentioned arrangement, the utility model realizes the pre-fixation of the adhesive on the winding end of the core, which facilitates the smooth progress of the core forming, shelling and other processes, while also effectively improving the problem of easy breakage of the electrode during battery charging and discharging, and can also avoid the adhesive moving in the shell and causing deformation of the core. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 This is a schematic structural diagram of a battery core according to an embodiment of the present invention;

[0034] Figure 2 This is a schematic structural diagram of a battery when the adhesive member according to one embodiment of the present invention is bonded to the winding core;

[0035] Figure 3 This is a schematic structural diagram of a battery when the adhesive member according to one embodiment of the present invention is bonded to the housing;

[0036] Figure 4 This is a schematic structural diagram of a battery core according to an embodiment of the present invention;

[0037] Figure 5 This is a side view of the adhesive structure of an embodiment of the present invention. Figure 1 ;

[0038] Figure 6 This is a schematic diagram of the main structure of the adhesive member according to one embodiment of the present invention. Figure 1 ;

[0039] Figure 7 This is a schematic diagram of the main structure of the adhesive member according to one embodiment of the present invention. Figure 2 ;

[0040] Figure 8 This is a schematic diagram of the main structure of the adhesive member according to one embodiment of the present invention. Figure 3 ;

[0041] Figure 9 This is a side view of the adhesive structure of an embodiment of the present invention. Figure 2 .

[0042] Among them, 100, winding core; 1, positive electrode sheet; 11, positive electrode current collector; 12, positive electrode active layer; 13, positive electrode ear; 14, straight area; 15, bending area; 101, double-sided area; 102, single-sided area; 103, empty foil area; 2, negative electrode sheet; 21, negative electrode current collector; 22, negative electrode active layer; 23, negative electrode ear; 3, adhesive; 31, substrate layer; 32, first adhesive layer; 321, adhesive part; 33, second adhesive layer; 200, shell. DETAILED DESCRIPTION

[0043] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention are within the scope of protection of the present invention.

[0044] The battery cell is the core component of a lithium-ion battery. It consists of a positive electrode sheet, a negative electrode sheet, and a separator interposed between the two. The positive electrode sheet, separator, and negative electrode sheet are stacked and wound to form a core. During the charge and discharge process, the battery cell expands, causing the electrode sheets to expand outward due to the outward force. If this expansion force cannot be released, the electrode sheets may break during cycling, affecting the battery's normal operation.

[0045] Based on this, an embodiment of the utility model provides a battery, which arranges an adhesive between the winding end of the core and the shell, and makes the bonding force between the adhesive and the core smaller than the bonding force between the adhesive and the shell. In this way, the winding end of the core can be pre-fixed by the adhesive, which facilitates the smooth progress of processes such as core forming and shell insertion. Moreover, since the bonding force between the adhesive and the core is smaller than the bonding force between the adhesive and the shell, the bonding force between the adhesive and the core is relatively small. When the electrode is subjected to an outward expansion force during the battery charging and discharging process, the binding force of the adhesive on the winding end is easily invalidated under the action of the outward expansion and squeezing of the core, such as making it easy for the adhesive to detach from the core, so that the electrode can expand outward to relieve the expansion force, thereby improving the problem of easy breakage of the electrode.

[0046] The battery provided by the present invention is described in detail below with reference to specific embodiments in conjunction with the accompanying drawings:

[0047] This embodiment provides a battery, which may be, for example, a lithium-ion battery. The battery can be used as a power source or energy storage unit for electronic devices, including, but not limited to, mobile devices (such as mobile phones, laptops, and tablets) and electric vehicles (such as pure electric vehicles, hybrid electric vehicles, and electric bicycles).

[0048] Reference Figures 1 to 9 As shown, the battery provided in this embodiment includes: a shell 200, a winding core 100 and an electrolyte.

[0049] The core 100 and the electrolyte are both located within the housing 200. The core 100 includes a positive electrode sheet 1, a negative electrode sheet 2, and a separator (not shown). The separator is located between the positive electrode sheet 1 and the negative electrode sheet 2 to prevent direct contact between the positive electrode sheet 1 and the negative electrode sheet 2. The positive electrode sheet 1, the separator, and the negative electrode sheet 2 are stacked and wound to form the core 100. For example, the housing 200 may be an aluminum-plastic film housing.

[0050] Reference Figures 1 to 3 As shown, the positive electrode sheet 1 may specifically include: a positive electrode current collector 11, a positive electrode active layer 12, and a positive electrode tab 13. The positive electrode active layer 12 is disposed on at least one side of the positive electrode current collector 11. Specifically, the positive electrode current collector 11 has two opposing sides, which are used to coat the positive electrode active layer 12. In a specific implementation, the positive electrode active layer 12 may be disposed on both sides of the positive electrode current collector 11, or only on one side.

[0051] The positive electrode current collector 11 may be, for example, aluminum foil, and the material of the positive electrode active layer 12 may be, for example, lithium cobalt oxide, ternary materials, lithium iron phosphate or other positive electrode active materials.

[0052] The negative electrode sheet 2 may specifically include: a negative electrode current collector 21, a negative electrode active layer 22, and a negative electrode tab 23. The negative electrode active layer 22 is disposed on at least one side of the negative electrode current collector 21. Specifically, the negative electrode current collector 21 has two opposing sides, which are used to coat the negative electrode active layer 22. In practice, the negative electrode active layer 22 may be disposed on both sides of the negative electrode current collector 21, or only on one side.

[0053] The negative electrode current collector 21 may be, for example, copper foil, and the material of the negative electrode active layer 22 may be, for example, graphite, silicon-based, or other negative electrode active materials.

[0054] Reference Figures 1 to 4 As shown, the battery further includes an adhesive member 3, which is disposed between the winding end of the core 100 and the housing 200. The adhesive force F1 between the adhesive member 3 and the core 100 is smaller than the adhesive force F2 between the adhesive member 3 and the housing 200.

[0055] Since the adhesive member 3 can be bonded to the winding end of the core 100, the winding end of the core 100 is pre-fixed to prevent the core 100 from becoming loose, thereby facilitating processes such as forming and shelling the core 100.

[0056] Since the battery will expand during charging and discharging, that is, the electrode will be subjected to outward squeezing force, by making the bonding force F1 between the adhesive 3 and the core 100 smaller than the bonding force F2 between the adhesive 3 and the shell 200, that is, making the bonding force F1 between the adhesive 3 and the core 100 relatively small, when the battery expands during charging and discharging and the electrode is subjected to outward expansion force, the binding force of the adhesive 3 on the winding end is easily invalidated, for example, the adhesive 3 is separated from the core 100, so that the electrode can expand outward and its expansion force is released, thereby preventing the electrode from breaking to a certain extent.

[0057] Since the adhesive member 3 can be bonded to the shell 200, and the bonding force F2 between the adhesive member 3 and the shell 200 is relatively larger than the bonding force F1 between the adhesive member 3 and the winding core 100, the reliability of the bonding between the adhesive member 3 and the shell 200 is guaranteed, thereby preventing the adhesive member 3 from moving inside the shell 200 to a certain extent, such as moving to the winding core 100 along the winding core 100. Figure 4 The core 100 is squeezed between the two sides in the upper and lower directions and the shell 200, especially after the adhesive 3 is separated from the core 100, it can prevent the adhesive 3 from running around, which in turn causes the core 100 to deform. The core 100 is well protected, which is conducive to ensuring the normal use of the battery.

[0058] Specifically, the core 100 is wound from the inside out, with the winding end located at the outermost circle of the core 100. For example, after the core 100 is wound and formed, it is placed in the housing 200, and then undergoes processes such as liquid injection, static rest, formation, capacity separation, and K value measurement (the battery's voltage drop per unit time), and then packaged into a battery.

[0059] For example, during the formation process and during the use of the battery after formation, when the core 100 expands outward, the bonding force F1 between the adhesive 3 and the core 100 is less than the bonding force F2 between the adhesive 3 and the shell 200, that is, the bonding force F1 between the adhesive 3 and the core 100 is relatively small, so that when the core 100 is formed at high temperature and high pressure, the binding force of the adhesive 3 on the core 100 is further reduced, for example, the adhesive 3 is separated from the core 100, so that when the battery expands during the charging and discharging process, the binding force of the adhesive 3 on the winding end fails, allowing the electrode to expand outward, thereby preventing the electrode from breaking to a certain extent.

[0060] In the battery provided in this embodiment, by disposing an adhesive member 3 between the winding end of the core 100 and the shell 200, the adhesive force F1 between the adhesive member 3 and the core 100 is smaller than the adhesive force F2 between the adhesive member 3 and the shell 200. Since the adhesive member 3 can adhere to the winding end of the core 100, it can prevent the core 100 from loosening before it is inserted into the shell, which facilitates the smooth execution of the core 100 molding and shell insertion processes during production, thereby improving battery production efficiency to a certain extent. Furthermore, since the adhesive member 3 can also adhere to the shell 200, and the adhesive force F1 between the adhesive member 3 and the core 100 is smaller than the adhesive force F2 between the adhesive member 3 and the shell 200, the adhesive force F1 between the adhesive member 3 and the core 100 is relatively small. This arrangement is due to the relatively small bonding force F1 between the adhesive 3 and the core 100. Therefore, when the core 100 expands during the charging and discharging process and the electrode is subjected to an outward expansion force, the adhesive 3 is subjected to the outward expansion and squeezing of the core 100, and the binding force of the adhesive 3 on the winding end is easily invalidated. For example, the adhesive 3 is easily separated from the core 100, so that the electrode can expand outward, and the expansion force of the electrode can be relieved and released, thereby effectively improving the problem of the electrode being easily broken during the charging and discharging process of the battery and ensuring the normal use of the battery.

[0061] At the same time, since the bonding force F1 between the adhesive 3 and the core 100 is smaller than the bonding force F2 between the adhesive 3 and the shell 200, the bonding reliability between the adhesive 3 and the shell 200 is guaranteed, thereby preventing the adhesive 3 from moving around in the shell 200 and squeezing the core 100 to a certain extent. Especially after the adhesive 3 is separated from the core 100, it can prevent the adhesive 3 from moving around, thereby causing deformation of the core 100, etc., thereby providing good protection for the core 100 and ensuring the normal use of the battery.

[0062] That is to say, through the above-mentioned arrangement, this embodiment realizes the pre-fixation of the adhesive 3 on the winding end of the core 100, which facilitates the smooth progress of the processes such as forming and shelling of the core 100. At the same time, it also effectively improves the problem of easy breakage of the electrode during the battery charging and discharging process, and can also avoid the adhesive 3 moving in the shell 200 and causing deformation of the core 100.

[0063] For example, taking the outermost circle of the core 100 as the positive electrode sheet 1, when the core 100 expands during charging and discharging, especially when the outermost circle of the negative electrode sheet 2 expands, it will push the positive electrode sheet 1 located on the outermost circle outward. Since the bonding force F1 between the adhesive 3 and the core 100 is relatively small, the adhesive 3 can easily separate from the core 100 under the action of the outward expansion and squeezing force exerted on the electrode sheet, thereby effectively improving the problem of breakage of the positive electrode sheet 1 during the cycle.

[0064] Combine Figures 1 to 3 As shown, in some embodiments, the winding core 100 includes a straight region 14 and bending regions 15 located at both ends of the straight region 14 .

[0065] Reference Figure 1 As shown, illustratively, in the direction from the winding beginning to the winding end of the positive electrode sheet 1, the positive electrode sheet 1 sequentially includes: a double-sided area 101, a single-sided area 102, and a hollow foil area 103. Among them, the double-sided area 101 is the area where the positive electrode active layer 12 is coated on both sides of the positive electrode current collector 11, the single-sided area 102 is the area where the positive electrode active layer 12 is coated on one side of the positive electrode current collector 11, and the hollow foil area 103 is the area where the positive electrode active layer 12 is not coated on both sides of the positive electrode current collector 11.

[0066] For example, taking the outermost circle of the winding core 100 as the positive electrode sheet 1 as an example, refer to Figure 1 As shown, the core 100 ends with the empty foil area 103 of the positive electrode sheet 1, located Figure 1 The outermost bend area 15 on the left side (i.e., the first bend area 15 on the left side from the outside to the inside) corresponds to the hollow foil area 103 of the positive electrode sheet 1. The second bend area 15 on the left side of the positive electrode sheet 1 from the outside to the inside is the single-sided area 102 of the positive electrode sheet 1. During rolling, the transition area A between the single-sided area 102 and the double-sided area 101 may be damaged by roller jumping, resulting in damage to the positive electrode current collector 11. Furthermore, during battery charging and discharging, the bend area 15 needs to withstand a large outward expansion force, which can easily cause fracture in the above-mentioned transition area A of the positive electrode sheet 1 and the area connected to the transition area A. Because the bonding force F1 between the adhesive 3 and the winding core 100 in this embodiment is relatively small, the adhesive 3 can easily separate from the winding core 100 under the outward expansion and extrusion force exerted on the electrode sheet, allowing the positive electrode sheet 1 to expand outward, thereby releasing the expansion force exerted on the positive electrode sheet 1, thereby avoiding fracture in the above-mentioned locations of the positive electrode sheet 1 to a certain extent.

[0067] For example, located Figure 1 The bending area 15 of the outermost circle on the middle right is the single-sided area 102 of the positive electrode sheet 1. Charging and discharging only occur on one side of the single-sided area 102, resulting in uneven force on the inner and outer sides of the positive electrode collector 11. The expansion force applied to the bending area 15 during the charging and discharging process of the battery is greater than that of the straight area 14. Since the bonding force F1 between the adhesive 3 and the winding core 100 in this embodiment is relatively small, the adhesive 3 can easily separate from the winding core 100 under the action of the outward expansion and extrusion force applied to the electrode sheet, thereby ensuring that the bending area 15 of the outermost circle on the right can expand outward during the charging and discharging process of the battery, so that the expansion force applied to the positive electrode sheet 1 can be relieved and released, thereby avoiding the occurrence of fracture at this position of the positive electrode sheet 1 to a certain extent.

[0068] In some embodiments, the adhesive force F1 between the adhesive member 3 and the winding core 100 satisfies: 0.05N / m≤F1≤6N / m 。 Exemplarily, F1 can be 0.05N / m, 0.1N / m, 0.15N / m, 0.2N / m, 0.25N / m, 0.3N / m, 0.4N / m, 0.5N / m, 0.6N / m, 0.7N / m, 0.8N / m, 0.9N / m, 1N / m, 2N / m, 3N / m, 3.025N / m, 3.5N / m, 4N / m, 5N / m, or 6N / m.

[0069] This arrangement not only ensures the pre-fixing effect of the adhesive 3 on the winding end of the core 100, avoiding the loosening of the core 100 before shelling and affecting the normal shelling process, but also makes it easy for the adhesive 3 and the core 100 to lose adhesion and separate when subjected to the outward squeezing force of the electrode, ensuring that the expansion force on the electrode is relieved and released, and improving the problem of the electrode being easily broken during the battery charging and discharging process.

[0070] In some embodiments, the adhesive force F2 between the adhesive member 3 and the housing 200 satisfies: 20 N / m≤F2≤39 N / m. For example, F2 can be 20 N / m, 24 N / m, 27 N / m, 29.5 N / m, 33 N / m, 36 N / m, or 39 N / m.

[0071] This arrangement further ensures the bonding effect and bonding stability between the adhesive member 3 and the shell 200 , and further avoids the situation where the adhesive member 3 moves around and squeezes the winding core 100 .

[0072] In some embodiments, the adhesive force F1 between the adhesive member 3 and the winding core 100 and the adhesive force F2 between the adhesive member 3 and the housing 200 satisfy the following relationship: 2.5% ≤ F1 / F2 ≤ 30%. For example, the ratio F1 / F2 can be 2.5%, 5%, 10%, 15%, 16.25%, 20%, 25%, or 30%.

[0073] This arrangement can ensure the pre-fixing effect of the adhesive 3 on the core 100, ensure the normal progress of the shell insertion process of the core 100, and make the adhesive 3 and the core 100 easy to lose adhesion and separate when subjected to the outward squeezing force of the electrode, ensure that the expansion force exerted on the electrode is released, improve the problem that the electrode is easily broken during the battery charging and discharging process, and at the same time enable the adhesive 3 to be stably and reliably bonded to the shell 200 to prevent the adhesive 3 from moving.

[0074] In some embodiments, reference Figures 1 to 2 As shown, the winding end of the winding core 100 is located in the straight area 14 , and the adhesive member 3 is arranged between the straight area 14 and the shell 200 .

[0075] This arrangement, on the one hand, facilitates the bonding operation of the adhesive 3 at the end of the winding, thereby improving the bonding efficiency; on the other hand, since the stress in the bending area 15 is concentrated compared to the straight area 14, by arranging the adhesive 3 in the straight area 14, it can, to a certain extent, avoid the adhesive 3 from accidentally falling off the core 100 or the adhesive 3 from breaking before entering the shell, thereby ensuring, to a certain extent, the bonding effect between the adhesive 3 and the core 100 before entering the shell.

[0076] In some embodiments, reference Figure 1 and Figure 2 As shown, when the winding end of the core 100 is the empty foil area 103 of the positive electrode sheet 1 (that is, the core 100 ends with the empty foil area 103 of the positive electrode sheet 1), the adhesive 3 is arranged between the empty foil area 103 of the positive electrode sheet 1 and the shell 200.

[0077] The above-mentioned bonding force F1 may be the bonding force between the adhesive member 3 and the empty foil area 103 .

[0078] In this way, by allowing the adhesive member 3 to adhere to the empty foil area 103, the winding end can be pre-fixed, thereby preventing the core 100 from loosening, facilitating the smooth progress of processes such as forming and inserting the core 100 into the shell, and also reducing the amount of end glue used at the winding end.

[0079] Specifically, refer to Figure 1 and Figure 2 As shown, for example, in the winding direction, the tail of the empty foil area 103 is located in the straight area 14, and the adhesive 3 can be bonded to the tail of the empty foil area 103 and to the outermost circle of the straight area 14, thereby achieving pre-fixation of the core 100.

[0080] In some embodiments, the winding end of the winding core 100 may be a diaphragm, and the adhesive 3 may be disposed between the diaphragm and the shell 200 .

[0081] For example, the bonding force F1 may be the bonding force between the adhesive 3 and the portion of the diaphragm.

[0082] In this way, the adhesive 3 can be bonded to the diaphragm at the end of the winding, so as to achieve pre-fixation of the winding end of the core 100 and realize the end of the core 100, thereby preventing the core 100 from loosening, facilitating the smooth progress of the processes such as forming and shelling of the core 100, and also reducing the amount of end glue used at the end of the winding.

[0083] In some embodiments, reference Figures 1 to 9As shown, the adhesive component 3 includes a substrate layer 31, a first adhesive layer 32, and a second adhesive layer 33. The first adhesive layer 32 is disposed on the side of the substrate layer 31 facing the winding core 100 and is bonded to the winding end of the winding core 100. The second adhesive layer 33 is disposed on the side of the substrate layer 31 facing the housing 200 and is bonded to the housing 200. In other words, the adhesive component 3 can be configured as a three-layer structure.

[0084] Illustratively, the adhesive force F1 is specifically the adhesive force between the first adhesive layer 32 and the winding core 100 , and the adhesive force F2 is specifically the adhesive force between the second adhesive layer 33 and the housing 200 .

[0085] In this way, the winding end can be pre-fixed by bonding the first adhesive layer 32 and the core 100, preventing the core 100 from loosening, which is beneficial to the production processes such as the core 100 molding and shelling. At the same time, the bonding force F1 between the first adhesive layer 32 and the core 100 is smaller than the bonding force F2 between the second adhesive layer 33 and the shell 200. That is, the bonding force F1 between the first adhesive layer 32 and the core 100 is relatively small, so that the first adhesive layer 32 and the core 100 can be easily separated when subjected to the outward squeezing force of the pole piece, so that the pole piece can expand outward, so that the expansion force can be effectively relieved and released, and the pole piece can be prevented from breaking. In addition, this can ensure the reliable bonding of the adhesive 3 on the shell 200, and to a certain extent avoid the adhesive 3 from running around in the shell 200.

[0086] For example, during a high-temperature and high-pressure forming process, the first adhesive layer 32 separates from the winding core 100 when subjected to the outward squeezing force of the electrode, while the second adhesive layer 33 exerts a strong adhesive force and is reliably bonded to the shell 200 .

[0087] In some embodiments, the material of the first adhesive layer 32 is selected from at least one of styrene-butadiene rubber (SBR), polyisobutylene (PIB), polyphenylene ether (PPE), polypropylene (PP), polyacrylate, styrene-butadiene ternary block copolymer (SBS), and styrene-isoprene-styrene ternary block copolymer (SIS).

[0088] In this way, the first adhesive layer 32 can be bonded to the end of the winding to pre-fix the core 100, which facilitates the processes of forming and shelling the core 100, and makes the bonding force between the first adhesive layer 32 and the core 100 relatively small, so that the first adhesive layer 32 can easily separate from the core 100 when subjected to the outward squeezing force of the electrode, allowing the electrode to expand outward, thereby improving the problem of the electrode being easily broken during the battery charging and discharging process.

[0089] Illustratively, this allows the first adhesive layer 32 to be bonded to the end of the winding before the core 100 is subjected to high-temperature and high-pressure formation, that is, at room temperature, to pre-fix the core 100, so as to facilitate the core 100 molding, shelling and other processes, and can be separated from the core 100 during the formation of the core 100, so that the adhesive 3 no longer restrains the core 100 during and after the formation, thereby improving the problem of the electrode being easily broken during the battery charging and discharging process.

[0090] For example, the temperature during the formation of the core 100 may be, for example, 80° C. to 90° C. That is, the first adhesive layer 32 may lose its adhesiveness after undergoing high temperature and high pressure formation and may be directly separated from the core 100 .

[0091] In some embodiments, along the first direction, the thickness d1 of the first adhesive layer 32 can satisfy the following: 3 μm≤d1≤6 μm.

[0092] Combine Figure 5 and Figure 9 As shown, the first direction here can be specifically Figure 5 and Figure 9 The thickness d1 of the first adhesive layer 32 is the thickness of the first adhesive layer 32 along the vertical direction. Figure 5 and Figure 9 For example, the thickness d1 may be 3 μm, 3.5 μm, 4 μm, 4.5 μm, 5 μm, 5.5 μm, or 6 μm.

[0093] By setting the thickness d1 of the first adhesive layer 32 within this range, not only the bonding force between the adhesive 3 and the core 100 is guaranteed, and the pre-fixing effect of the adhesive 3 on the core 100 is guaranteed, thereby preventing the core 100 from becoming loose before shelling and affecting the normal shelling process, but also the first adhesive layer 32 can be further ensured to be easier to fall off the core 100 when subjected to the outward squeezing force of the electrode, thereby ensuring that the expansion force on the electrode is released, thereby improving the problem of the electrode being easily broken during the battery charging and discharging process.

[0094] In some embodiments, the relative molecular mass of the first adhesive layer 32 can be set at 2×10 5 ~3.5×10 5For example, it can be 2×10 5 , 2.7×10 5 , 2.9×10 5 , 3×10 5 , 3.1×10 5 , 3.3×10 5 , 3.5×10 5 .

[0095] The relative molecular mass of the first adhesive layer 32 refers to the sum of the relative atomic masses of the atoms in the molecules constituting the first adhesive layer 32 .

[0096] By setting the relative molecular mass of the first adhesive layer 32 within the above range, the self-adhesive effect of the first adhesive layer 32 can be guaranteed to a certain extent, thereby ensuring the bonding effect between the first adhesive layer 32 and the substrate layer 31, as well as the core 100, so as to facilitate the molding and shelling operations of the core 100; at the same time, it is conducive to making the first adhesive layer 32 easier to fall off from the core 100 when subjected to the outward squeezing force of the pole piece.

[0097] In some embodiments, the substrate layer 31 may specifically be a film layer.

[0098] In some embodiments, the material of the substrate layer 31 can be selected from at least one of polyethylene terephthalate (PET, also known as polyester), polypropylene (PP), polyethylene (PE), and polyvinyl chloride (PVC).

[0099] This configuration enables the base material layer 31 to have good heat resistance and high temperature resistance, so as to stably support the first adhesive layer 32 and the second adhesive layer 33 , thereby ensuring the stability of the entire adhesive component 3 .

[0100] In some embodiments, along the first direction, the thickness d2 of the base material layer 31 can satisfy the following: 5 μm≤d2≤12 μm.

[0101] Reference Figure 5 and Figure 9 As shown, the first direction here can be specifically Figure 5 and Figure 9 The thickness d2 of the substrate layer 31 is specifically the thickness of the substrate layer 31 along the vertical direction. Figure 5 and Figure 9 For example, the thickness d2 may be 5 μm, 6 μm, 7 μm, 8.5 μm, 10 μm, 11 μm, or 12 μm.

[0102] By setting the thickness d2 of the substrate layer 31 within the above range, while ensuring that the substrate layer 31 stably supports the first adhesive layer 32 and the second adhesive layer 33 and the stability of the entire adhesive component 3, it can also avoid the entire adhesive component 3 being too thick, which will cause the core 100 to be too thick.

[0103] In some embodiments, reference Figures 6 to 8 As shown, the projected area of ​​the first adhesive layer 32 on the substrate layer 31 is not larger than the surface area of ​​the substrate layer 31 facing the first adhesive layer 32 .

[0104] Specifically, for example, when the projected area of ​​the first adhesive layer 32 on the substrate layer 31 is equal to the surface area of ​​the substrate layer 31, that is, the first adhesive layer 32 is fully coated on the substrate layer 31, this can improve the convenience of coating the first adhesive layer 32 on the substrate layer 31 to a certain extent, and improve the coating efficiency to a certain extent.

[0105] For another example, when the projected area of ​​the first adhesive layer 32 on the substrate layer 31 is smaller than the surface area of ​​the substrate layer 31, compared with the solution of fully coating the first adhesive layer 32, the bonding area between the first adhesive layer 32 and the winding core 100 can be reduced to a certain extent, thereby ensuring that the first adhesive layer 32 and the winding core 100 are more likely to lose adhesion and separate when subjected to the outward squeezing force of the electrode.

[0106] Specifically, when the projected area of ​​the first adhesive layer 32 on the substrate layer 31 is smaller than the surface area of ​​the substrate layer 31 , in some embodiments, the first adhesive layer 32 may include at least two adhesive portions 321 , and the at least two adhesive portions 321 are arranged at intervals on the substrate layer 31 .

[0107] This arrangement can improve the uniformity of the coating of the first adhesive layer 32 on the substrate layer 31 to a certain extent, and ensure the bonding force between the adhesive 3 and the core 100 to a certain extent to ensure the pre-fixing effect at the end of the winding, while further ensuring that the adhesive 3 is easier to separate from the core 100 when subjected to the outward squeezing force of the electrode, so that the expansion force on the electrode can be alleviated and released, thereby improving the problem of the electrode being easily broken during the charging and discharging process of the battery.

[0108] For example, refer to Figure 6 As shown, at least two bonding portions 321 may be arranged in an array on the substrate layer 31. For example, the bonding portion 321 may be in a shape of a diamond, a square, a rectangle, a circle, an ellipse, or the like.

[0109] For example, refer to Figure 7 As shown, at least two adhesive portions 321 may be arranged alternately in a grid pattern on the substrate layer 31 .

[0110] In addition, refer to Figure 8As shown, at least two bonding portions 321 may be spaced apart and arranged parallel to each other, for example, in a zebra-shaped structure.

[0111] In some embodiments, the first adhesive layer 32 is further doped with a dopant, and the material of the dopant can be selected from at least one of alicyclic petroleum resin, rosin, hydrogenated rosin resin, and terpene resin.

[0112] By doping the first adhesive layer 32 with a dopant to improve the viscosity of the first adhesive layer 32 , the core 100 will not become loose before being placed in the shell, thereby further ensuring smooth processes such as forming and placing the core 100 in the shell.

[0113] In some embodiments, the mass percentage of the dopant in the first glue layer 32 can be in the range of 0.5% to 2%. For example, the mass percentage of the dopant can be 0.5%, 1%, 1.25%, 1.5%, 1.6%, 1.7%, 1.8%, 1.9%, or 2%.

[0114] By setting the mass percentage of the dopant in the first adhesive layer 32 within this range, the viscosity of the first adhesive layer 32 can be guaranteed, thereby ensuring the pre-fixing effect of the core 100 when the adhesive member 3 is bonded to the core 100, avoiding the loosening of the core 100 before being put into the shell, and at the same time ensuring that the first adhesive layer 32 is more easily separated from the core 100 when subjected to the outward squeezing force of the pole piece.

[0115] In some embodiments, the relative molecular mass of the dopant in the first glue layer 32 may be in the range of 200 to 1500.

[0116] The relative molecular mass of the dopant refers to the sum of the relative atomic masses of the atoms in the molecules constituting the dopant.

[0117] By setting the relative molecular mass of the dopant within the above range, the viscosity of the first adhesive layer 32 can be guaranteed, thereby ensuring the bonding force between the adhesive component 3 and the core 100, ensuring the pre-fixing effect of the core 100, and avoiding the core 100 from loosening before being put into the shell. At the same time, it ensures that the first adhesive layer 32 is more easily separated from the core 100 when subjected to the outward squeezing force of the pole piece.

[0118] In some embodiments, the material of the second adhesive layer 33 is selected from at least one of styrene-isoprene copolymer, linear triblock copolymer (Styrene Ethylene Butylene Styrene, SEBS), hydrogenated styrene-isoprene-styrene block copolymer (SEPS), and epoxidized styrene-butadiene-styrene block copolymer (ESBS).

[0119] In this way, the bonding force between the second adhesive layer 33 and the housing 200 can be guaranteed to a certain extent, thereby achieving reliable fixation of the adhesive component 3 and preventing the adhesive component 3 from moving around in the housing 200 .

[0120] In addition, such a configuration enables the second adhesive layer 33 to exert a stronger adhesive force during the high-temperature and high-pressure forming process and to be reliably bonded to the housing 200 .

[0121] In some embodiments, the relative molecular weight of the second glue layer 33 can be set at 7×10 3 ~2×10 5 For example, it can be 7×10 3 , 9×10 3 , 2×10 4 , 5×10 4 , 8×10 4 , 1×10 5 , 2×10 5 .

[0122] The relative molecular mass of the second adhesive layer 33 refers to the sum of the relative atomic masses of the atoms in the molecules constituting the second adhesive layer 33 .

[0123] By setting the relative molecular weight of the second adhesive layer 33 within the above range, the self-adhesive effect of the second adhesive layer 33 can be guaranteed to a certain extent, thereby ensuring the bonding effect between the second adhesive layer 33 and the shell 200, thereby further preventing the adhesive 3 from running around and squeezing the core 100.

[0124] In some embodiments, along the first direction, the thickness d3 of the second adhesive layer 33 and the thickness d1 of the first adhesive layer 32 can satisfy the following relationship: 2d1≤d3≤5d1.

[0125] Reference Figure 1 、 Figure 5 and Figure 9As shown, the first direction here can be specifically Figure 5 and Figure 9 The thickness d3 of the second adhesive layer 33 is the thickness of the second adhesive layer 33 along the vertical direction. Figure 5 and Figure 9 For example, d3=2*d1, d3=2.5*d1, d3=3*d1, d3=3.5*d1, d3=4*d1, d3=4.5*d1, and d3=5*d1.

[0126] This arrangement makes the thickness d3 of the second adhesive layer 33 thicker than the thickness d1 of the first adhesive layer 32, which not only helps to ensure that the first adhesive layer 32 is easier to separate from the winding core 100 when subjected to the outward squeezing force of the electrode, but also further ensures the reliable bonding of the second adhesive layer 33 to the shell 200.

[0127] In some embodiments, the sum of the thickness d1 of the first adhesive layer 32 and the thickness d3 of the second adhesive layer 33 can satisfy the following relationship: d1 + d3 ≥ 20 μm. For example, the sum of the thickness d1 and the thickness d3 can be 20 μm, 20.5 μm, 21 μm, 21.5 μm, 22 μm, 22.5 μm, or 23 μm.

[0128] This arrangement ensures the bonding effect between the adhesive 3 and the core 100 to prevent the core 100 from becoming loose, which is beneficial to the smooth progress of processes such as forming and shelling the core 100. It also further ensures the bonding effect between the adhesive 3 and the shell 200, ensuring that the adhesive 3 is reliably fixed on the shell 200, and is beneficial for the adhesive 3 to be more easily separated from the core 100 under the action of the outward squeezing force of the pole piece.

[0129] In some embodiments, the second adhesive layer 33 is further doped with a tackifier.

[0130] By adding a tackifier into the second adhesive layer 33, the viscosity of the second adhesive layer 33 is further improved, thereby further improving the bonding force between the second adhesive layer 33 and the shell 200. When the adhesive component 3 is subjected to the outward squeezing force of the pole piece, the first adhesive layer 32 is easier to separate from the winding core 100.

[0131] The material of the tackifier can be selected from at least one of alicyclic petroleum resin, rosin, hydrogenated rosin resin, and terpene resin.

[0132] In some embodiments, the mass percentage of the tackifier in the second adhesive layer 33 can be set between 1% and 5%. For example, the mass percentage of the tackifier can be 1%, 2%, 2.5%, 3%, 4%, 4.5%, or 5%.

[0133] By setting the mass percentage of the tackifier in the second adhesive layer 33 within this range, the viscosity of the second adhesive layer 33 can be ensured, so that the bonding force between the second adhesive layer 33 and the base material layer 31 can be enhanced, making it easier for the adhesive component 3 to be reliably fixed on the shell 200, and further improving the bonding effect between the adhesive component 3 and the shell 200, further avoiding the adhesive component 3 from moving around in the shell 200 and squeezing the core 100, and this is also conducive to ensuring that the adhesive component 3 is easier to separate from the core 100 under the action of the outward squeezing force of the pole piece.

[0134] In some embodiments, the relative molecular mass of the tackifier can be set between 200 and 1500. The relative molecular mass of the tackifier refers to the sum of the relative atomic masses of the atoms in the molecules constituting the tackifier.

[0135] By setting the relative molecular weight of the tackifier within the above range, the viscosity of the second adhesive layer 33 can be increased, thereby improving the bonding effect and reliability between the second adhesive layer 33 and the housing 200 .

[0136] In some embodiments, along the first direction, the total thickness D of the adhesive member 3 can satisfy the following: 15 μm≤D≤35 μm.

[0137] Reference Figure 1 、 Figure 5 and Figure 9 As shown, the first direction here can be specifically Figure 5 and Figure 9 The total thickness D of the adhesive member 3 is the thickness of the adhesive member 3 along the vertical direction. Figure 5 and Figure 9 Thickness in the upper and lower directions.

[0138] Exemplarily, when the adhesive member 3 includes a first adhesive layer 32 and a substrate layer 31, the total thickness D of the adhesive member 3 is the sum of the thickness d1 of the first adhesive layer 32 and the thickness d2 of the substrate layer 31. When the adhesive member 3 includes a first adhesive layer 32, a substrate layer 31, and a second adhesive layer 33, the total thickness D of the adhesive member 3 is the sum of the thickness d1 of the first adhesive layer 32, the thickness d2 of the substrate layer 31, and the thickness d3 of the second adhesive layer 33. Exemplarily, the total thickness D of the adhesive member 3 can be, for example, 15 μm, 20 μm, 23 μm, 25 μm, 30 μm, 33 μm, or 35 μm.

[0139] By setting the total thickness D of the adhesive 3 within this range, the adhesive 3 can, to a certain extent, ensure the pre-fixation of the core 100 by the adhesive 3 before the core 100 is inserted into the shell, preventing the core 100 from becoming loose before insertion and affecting the normal insertion process. At the same time, this further ensures the bonding effect of the adhesive 3 to the shell 200, thereby further preventing the adhesive 3 from moving around. In particular, after the adhesive 3 is separated from the core 100, the adhesive 3 can be firmly fixed to the shell 200, further preventing the adhesive 3 from moving and squeezing the core 100. Furthermore, this setting can, to a certain extent, prevent the situation where the total thickness of the adhesive 3 is too thick, which leads to an increase in battery volume and a subsequent decrease in the battery's energy density per unit volume.

[0140] In some embodiments, along the second direction, the width h of the adhesive member 3 can specifically satisfy the following: 10 mm ≤ h ≤ 35 mm.

[0141] Reference Figures 1 to 4 As shown, the second direction here can be specifically Figure 3 and Figure 4 The left and right directions in the embodiment may be, for example, the width direction of the core 100. The width h of the adhesive member 3 is the width of the adhesive member 3 along the Figure 3 and Figure 4 The width in the left-right direction. Exemplarily, the width h can be 10 mm, 15 mm, 18 mm, 20 mm, 22.5 mm, 25 mm, 30 mm, or 35 mm.

[0142] By setting the width h of the adhesive member 3 within this range, the adhesive area between the adhesive member 3 and the core 100 can be ensured before the core 100 is inserted into the shell, thereby ensuring the pre-fixation effect of the adhesive member 3 on the core 100, and improving the bonding effect between the adhesive member 3 and the shell 200, thereby reliably fixing the adhesive member 3 and further preventing the adhesive member 3 from moving within the shell 200. At the same time, this setting can also prevent the adhesive member 3 from wrinkling and curling easily due to an excessive width to a certain extent, thereby improving the convenience of bonding and further ensuring the bonding effect.

[0143] In some embodiments, the length L of the adhesive member 3 along the third direction satisfies: 10 mm ≤ L ≤ H, where H is the length of the winding core 100 along the third direction.

[0144] Reference Figure 4 As shown, the third direction here can be specifically Figure 4 The vertical direction in the winding core 100 is, for example, the length direction of the winding core 100. The length L of the adhesive member 3 is the length of the adhesive member 3 along the winding core 100. Figure 4 The length in the vertical direction of the core 100 is H, which is the length of the core 100 along the vertical direction of the core 100. Figure 4 The length in the upper and lower directions.

[0145] For example, when H is 50 mm, L can be 10 mm, 15 mm, 20 mm, 25 mm, 30 mm, 35 mm, 40 mm, 45 mm, or 50 mm.

[0146] This arrangement not only ensures that the adhesive member 3 has a certain length to pre-fix the core 100 before the core 100 is inserted into the shell, ensuring smooth molding and insertion of the core 100, but also ensures the bonding area between the adhesive member 3 and the shell 200, thereby ensuring the bonding effect between the adhesive member 3 and the shell 200. In particular, after the adhesive member 3 is separated from the core 100, the reliable fixation of the adhesive member 3 on the shell 200 can further prevent the adhesive member 3 from moving within the shell 200. This can also, to a certain extent, prevent the adhesive member 3 from being too long, resulting in material waste of the adhesive member 3.

[0147] In this document, it should be noted that, unless otherwise expressly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense. For example, it can be a fixed connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to the specific circumstances. In addition, the orientations or positional relationships indicated by the terms "upper", "lower", "left", "right", "front", "back", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc. are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to this application.

[0148] In this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of additional identical elements in the process, method, article, or apparatus comprising the element.

[0149] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent replacements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A battery, characterized in that: It comprises a shell (200), a winding core (100) and an adhesive component (3); The winding core (100) is located in the shell (200), and the adhesive component (3) is arranged between the winding end of the winding core (100) and the shell (200); The adhesive force F1 between the adhesive member (3) and the winding core (100) is smaller than the adhesive force F2 between the adhesive member (3) and the shell (200).

2. The battery according to claim 1, characterized in that The bonding force F1 between the adhesive member (3) and the winding core (100) satisfies the following conditions: 0.05 N / m≤F1≤6 N / m; And / or, the bonding force F2 between the adhesive member (3) and the housing (200) satisfies: 20 N / m≤F2≤39 N / m; And / or, the adhesive force F1 between the adhesive member (3) and the winding core (100), and the adhesive force F2 between the adhesive member (3) and the shell (200) satisfy: 2.5%≤F1 / F2≤30%.

3. The battery according to claim 1, characterized in that The adhesive member (3) comprises a base material layer (31), a first adhesive layer (32) and a second adhesive layer (33); The first adhesive layer (32) is arranged on a side of the base material layer (31) facing the winding core (100), and the first adhesive layer (32) is bonded to the winding end of the winding core (100); The second adhesive layer (33) is arranged on a side of the base material layer (31) facing the housing (200), and the second adhesive layer (33) is bonded to the housing (200).

4. The battery according to claim 3, characterized in that The material of the first adhesive layer (32) is selected from at least one of styrene-butadiene rubber, polyisobutylene, polyethylene phenylene ether, polypropylene, polyacrylate, styrene-butadiene terblock copolymer, and styrene-isoprene-styrene terblock copolymer; And / or, the material of the second adhesive layer (33) is selected from at least one of styrene-isoprene copolymer, linear triblock copolymer, hydrogenated styrene-isoprene-styrene block copolymer, and epoxidized styrene-butadiene-styrene block copolymer.

5. The battery according to claim 3, characterized in that In the first direction, the thickness d1 of the first adhesive layer (32) satisfies: 3 μm≤d1≤6 μm; And / or, along the first direction, the thickness d3 of the second adhesive layer (33) and the thickness d1 of the first adhesive layer (32) satisfy: 2d1≤d3≤5d1; And / or, along the first direction, the sum of the thickness d1 of the first adhesive layer (32) and the thickness d3 of the second adhesive layer (33) satisfies: d1+d3≥20 μm; And / or, along the first direction, the thickness d2 of the base material layer (31) satisfies: 5 μm≤d2≤12 μm.

6. The battery according to claim 3, characterized in that The projected area of ​​the first adhesive layer (32) on the substrate layer (31) is not larger than the surface area of ​​the substrate layer (31) on the side facing the first adhesive layer (32); And / or, the first adhesive layer (32) includes at least two adhesive portions (321), and the at least two adhesive portions (321) are arranged at intervals on the base material layer (31); At least two of the bonding portions (321) are arranged in an array on the substrate layer (31); or, at least two of the bonding portions (321) are arranged in a grid-like staggered manner on the substrate layer (31); or, at least two of the bonding portions (321) are arranged parallel to each other.

7. The battery according to claim 3, characterized in that The second adhesive layer (33) is also doped with a tackifier.

8. The battery according to any one of claims 1 to 7, characterized in that In the first direction, the total thickness D of the adhesive member (3) satisfies: 15 μm≤D≤35 μm; And / or, along the second direction, the width h of the adhesive member (3) satisfies: 10 mm ≤ h ≤ 35 mm; And / or, along the third direction, the length L of the adhesive member (3) satisfies: 10 mm ≤ L ≤ H, wherein H is the length of the winding core (100) along the third direction.

9. The battery according to any one of claims 1 to 7, characterized in that The winding core (100) comprises a straight area (14) and bending areas (15) located at both ends of the straight area (14); the winding end of the winding core (100) is located in the straight area (14); and the adhesive component (3) is arranged between the straight area (14) and the shell (200).

10. The battery according to any one of claims 1 to 7, characterized in that The winding core (100) comprises a positive electrode sheet (1), a negative electrode sheet (2), and a separator arranged between the positive electrode sheet (1) and the negative electrode sheet (2); the positive electrode sheet (1), the separator, and the negative electrode sheet (2) are stacked and wound to form the winding core (100); The winding end of the winding core (100) is the empty foil area (103) of the positive electrode sheet (1), and the adhesive component (3) is arranged between the empty foil area (103) of the positive electrode sheet (1) and the shell (200); or, the winding end of the winding core (100) is the diaphragm, and the adhesive component (3) is arranged between the diaphragm and the shell (200).

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