Battery cell and battery

Abstract

The utility model discloses a kind of battery and electric core, electric core includes: electric core body, with first end face, second end face, first side and second side, second end face and first end face are oppositely arranged in the length direction of electric core body, second side and first side are oppositely arranged in the thickness direction of electric core body;Positive lug and negative lug are welded with electric core body and set out from first end face;Glue paper, with first side, second end face and second side are sequentially bonded to be arranged in electric core body;Wherein, glue paper includes the first bonding portion corresponding with second end face, multiple through holes are structured on glue paper, multiple through holes are at least distributed and set in first bonding portion, and the width ratio of glue paper and electric core body is 60%~70%.The present electric core can reduce the depth of indentation on aluminum plastic film after formation hot-pressing process, effectively avoid the situation that outer layer pole piece of electric core is folded or even torn, to protect the diaphragm from being damaged, prevent internal short circuit of electric core, improve the safety and reliability of battery.

Description

Technical Field

[0001] This utility model relates to the field of lithium battery technology, and in particular to a battery cell and battery. Background Technology

[0002] Lithium batteries, as batteries containing lithium elements (including metallic lithium, lithium alloys, lithium ions, lithium polymers, etc.) in an electrochemical system, are widely used in consumer electronics and other fields due to their outstanding advantages such as high energy density, long cycle life and low self-discharge rate.

[0003] The mainstream types of lithium batteries on the market include stacked cells and wound cells. Stacked cells are formed by stacking positive and negative electrodes and separators in sequence, which has advantages such as regular structure and low internal resistance. On the other hand, cells are formed by winding positive and negative electrodes and separators in sequence, which has certain advantages in terms of production efficiency and cost control, and therefore occupies a considerable share of the market.

[0004] During the battery cell manufacturing process, to ensure the stability and integrity of the cell structure and prevent problems such as loosening and displacement during subsequent use, the head and tail of the cell are usually fixed with adhesive wrapping. Currently, traditional tail-end adhesive wrapping technology generally adopts a double-layer adhesive paper structure with spaced intervals. In this structure, there is an exposed area between the two layers of adhesive paper to allow for smooth electrolyte passage. However, when the cell enters the formation and hot-pressing process, the exposed area of ​​the electrode edge will compress the aluminum-plastic film, forming deep indentations on the surface of the aluminum-plastic film. During lithium battery drop tests, these indentations come into contact with, rub against, or collide with the outer electrode of the cell, which can easily cause the outer electrode of the cell to fold or even tear, thereby damaging the separator. Once the electrode is damaged, the separator will also be damaged, leading to a short circuit inside the cell, seriously affecting the safety and reliability of the battery. Utility Model Content

[0005] The main purpose of this utility model is to propose a battery cell that aims to solve, to a certain extent, the technical problem that the double-sided adhesive paper structure at the tail of the current battery cell causes deep indentations in the aluminum-plastic film, which easily leads to the folding or even tearing of the outer electrode sheet of the battery cell.

[0006] To achieve the above objectives, this utility model proposes a battery cell, which includes:

[0007] The battery cell body has a first end face, a second end face, a first side face, and a second side face. The second end face and the first end face are disposed opposite to each other in the length direction of the battery cell body, and the second side face and the first side face are disposed opposite to each other in the thickness direction of the battery cell body.

[0008] The positive and negative tabs are welded to the battery cell body and extend from the first end face;

[0009] Adhesive tape is sequentially bonded to the first side surface, the second end surface, and the second side surface to be wrapped around the battery cell body;

[0010] The adhesive tape includes a first adhesive portion corresponding to the second end face, and the adhesive tape has a plurality of through holes, which are at least distributed in the first adhesive portion. The width ratio of the adhesive tape to the battery cell body is 60% to 70%.

[0011] Optionally, in the width direction of the battery cell body, the distance between the adhesive tape and one side of the battery cell body is D1, and the distance between the adhesive tape and the other side of the battery cell body is D2, satisfying: 0mm≤|D1-D2|≤4mm.

[0012] Optionally, the adhesive tape further includes a second adhesive portion corresponding to the first side and a third adhesive portion corresponding to the second side;

[0013] In the winding direction of the adhesive tape, the length of the second adhesive portion is L1 and the length of the third adhesive portion is L2, satisfying: 0.1mm≤L1≤20mm, 0.1mm≤L2≤20mm, where 0mm≤|L1-L2|≤1mm.

[0014] Optionally, the plurality of through holes are also distributed in the second adhesive portion and the third adhesive portion.

[0015] Optionally, the area ratio of the plurality of through holes to the area of ​​the adhesive paper is 60% to 85%.

[0016] Optionally, the density of the plurality of through holes on the first adhesive portion is higher than the density of the through holes on the second adhesive portion and the third adhesive portion.

[0017] Optionally, the plurality of through holes are arranged in an array.

[0018] Optionally, the spacing between any two adjacent through holes is equal.

[0019] Optionally, the shape of the through hole includes at least one of circular, elliptical, fan-shaped, and polygonal shapes.

[0020] This utility model also proposes a battery comprising a casing and a battery cell as described above, wherein the battery cell is disposed within the casing.

[0021] In this novel battery cell, the adhesive paper wrapped around the bottom of the cell body has multiple through holes. These through holes are distributed at least in the first adhesive portion corresponding to the second end face, allowing the electrolyte to pass through smoothly. Furthermore, the width ratio of the adhesive paper to the cell body is 60% to 70%, enabling a large-scale / regional wrapping of the tail electrode edge of the cell body using a single adhesive paper. During the hot-pressing process of cell formation, the tail electrode edge of the cell body is squeezed against the aluminum-plastic film by the flexible adhesive paper, reducing the indentation depth on the aluminum-plastic film surface. Thus, when the battery undergoes a drop test, the shallower indentation on the aluminum-plastic film surface significantly reduces the degree of contact, friction, or collision between the aluminum-plastic film and the outer electrode of the cell, effectively preventing the outer electrode of the cell from folding or even tearing. This protects the separator from damage, prevents internal short circuits, and significantly improves the safety and reliability of the battery. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the battery cell structure in one embodiment of the present invention;

[0023] Figure 2 for Figure 1 A schematic diagram of the battery cell from another perspective in the embodiment;

[0024] Figure 3 for Figure 1 A schematic diagram of the adhesive tape structure of the battery cell in the embodiment;

[0025] Figure 4 This is a schematic diagram of the battery cell structure in another embodiment of the present invention;

[0026] Figure 5 for Figure 4 A schematic diagram of the battery cell from another perspective in the embodiment;

[0027] Figure 6 for Figure 4 A schematic diagram of the adhesive tape structure of the battery cell in the embodiment;

[0028] Label Explanation:

[0029] label name label name 100 Battery cell body 111 First end face 112 Second end face 121 First side view 122 Second side 200 Positive electrode ear 300 Negative ear 400 Adhesive tape 410 First adhesive part 10 Through hole 420 Second adhesive part 430 Third Adhesive Part

[0030] The realization of the purpose, functional features and advantages of this utility model will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0031] The solutions in the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this utility model, and not all of them. Based on the embodiments of this utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of this utility model.

[0032] It should be noted that all directional indicators (such as up, down, left, right, front, back, etc.) in this utility model embodiment are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicator will also change accordingly.

[0033] It should also be noted that when a component is described as "fixed to" or "set on" another component, it can be directly on the other component or there may be an intervening component present. When a component is described as "connected to" another component, it can be directly connected to the other component or there may be an intervening component present.

[0034] Furthermore, the use of terms such as "first" and "second" in this utility model is for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. Additionally, the technical solutions of the various embodiments can be combined with each other, but only on the basis of being achievable by those skilled in the art. When the combination of technical solutions is contradictory or impossible to implement, such a combination of technical solutions should be considered non-existent and not within the scope of protection claimed by this utility model.

[0035] This utility model embodiment proposes a battery cell, referring to... Figure 1 and Figure 2 The battery cell includes:

[0036] The cell body 100 has a first end face 111, a second end face 112, a first side face 121 and a second side face 122. The second end face 112 and the first end face 111 are disposed opposite to each other in the length direction of the cell body 100, and the second side face 122 and the first side face 121 are disposed opposite to each other in the thickness direction of the cell body 100.

[0037] The positive electrode tab 200 and the negative electrode tab 300 are welded to the battery cell body 100 and extend from the first end face 111.

[0038] Adhesive tape 400 is sequentially bonded to the first side 121, the second end face 112, and the second side 122 to be wrapped around the battery cell body 100.

[0039] The adhesive tape 400 includes a first adhesive portion 410 corresponding to the second end face 112. The adhesive tape 400 has a plurality of through holes 10, which are at least distributed in the first adhesive portion 410. The width ratio of the adhesive tape 400 to the battery cell body 100 is 60% to 70%.

[0040] In this embodiment, the cell body 100 can adopt a wound or stacked structure, formed by alternating wound or stacked positive electrode sheets, separators, and negative electrode sheets. Preferably, the cell body 100 is a wound cell body 100. The positive electrode sheet includes a positive current collector (such as aluminum foil) and a positive active material (such as lithium cobalt oxide, ternary materials, etc.) coated thereon, and the negative electrode sheet includes a negative current collector (such as copper foil) and a negative active material (such as graphite) coated thereon. The separator is made of a polymer material with a microporous structure (such as polyethylene, polypropylene), used to isolate the positive and negative electrode sheets and allow lithium ions to pass through.

[0041] The cell body 100 has a first end face 111, a second end face 112, a first side face 121, and a second side face 122 based on its geometry. In the length direction of the cell body 100, the first end face 111 (head end face) and the second end face 112 (tail end face) are opposite to each other; in the thickness direction of the cell body 100, the first side face 121 (front side face) and the second side face 122 (rear side face) are opposite to each other.

[0042] In the width direction of the cell body 100, positive tabs 200 and negative tabs 300 are spaced apart. One end of the positive tab 200 is welded and fixed to the positive electrode in the cell body 100, and the other end extends from the first end face 111 of the cell body 100; one end of the negative tab 300 is welded and fixed to the negative electrode in the cell body 100, and the other end extends from the first end face 111 of the cell body 100. The positive tab 200 is made of aluminum, and the negative tab 300 is made of nickel or nickel-plated copper to ensure good conductivity and welding reliability with the corresponding electrode. To improve welding strength, the welding points of the positive tab 200 and negative tab 300 to the cell body 100 can be ultrasonically welded or laser welded.

[0043] The tail of the battery cell body 100 has an adhesive wrapping. Adhesive tape 400 is sequentially bonded to the first side surface 121, the second end surface 112, and the second side surface 122 to be wound around the battery cell body 100. The adhesive tape 400 can be made of a material with good flexibility and electrolyte resistance, such as polypropylene (PP), polyethylene (PE), or polyester (PET), and its thickness can be 20μm-50μm. One side of the adhesive tape 400 is coated with a high-temperature resistant and electrolyte-resistant pressure-sensitive adhesive (such as an acrylic adhesive), with an adhesive strength of 5-15 N / cm.

[0044] The adhesive tape 400 has a first adhesive portion 410 corresponding to the second end face 112 of the battery cell body 100. This portion has multiple through holes 10. When the first adhesive portion 410 is bonded to the second end face 112, the through holes 10 are positioned opposite the second end face 112. Meanwhile, the width ratio of the adhesive tape 400 to the battery cell body 100 is limited to 60% to 70%. For example, if the width of the battery cell body 100 is 65mm, the width of the adhesive tape 400 can be set to 39mm, 42mm, or 45.5mm; if the width of the battery cell body 100 is 68mm, the width of the adhesive tape 400 can be selected as 40.8mm, 44mm, or 47.6mm.

[0045] In the actual manufacturing process, the cell body 100 is first prepared. Positive and negative electrode plates are then combined with a separator using a specific process to form a cell body 100 structure having a first end face 111, a second end face 112, a first side face 121, and a second side face 122. Next, the positive electrode tab 200 and the negative electrode tab 300 are securely connected to the cell body 100 using a welding process, with the positive electrode tab 200 and the negative electrode tab 300 extending from the first end face 111 for subsequent connection to external circuitry.

[0046] Then, according to the requirement that the width ratio of the adhesive tape 400 to the cell body 100 is 60% to 70%, select an appropriate size of adhesive tape 400. First, adhere one end of the adhesive tape 400 to the first side surface 121 of the cell body 100. Then, wrap it around the second end surface 112 of the cell body 100. During the wrapping process, ensure that the first adhesive portion 410 of the adhesive tape 400 covers the second end surface 112, and ensure that the through hole 10 on the first adhesive portion 410 is aligned with the second end surface 112. Finally, adhere the adhesive tape 400 to the second side surface 122 of the cell body 100, completing the wrapping of the adhesive tape 400 around the cell body 100. In this process, the through hole 10 allows the electrolyte to flow smoothly at the tail of the cell, ensuring the normal electrochemical performance of the cell.

[0047] In the hot pressing process of battery cell formation, the exposed area of ​​the electrode edge in the traditional double adhesive paper 400 structure will exert concentrated pressure on the aluminum-plastic film. However, in the battery cell of this embodiment, since the width ratio of the adhesive paper 400 to the battery cell body 100 is reasonable, the electrode edge at the tail of the battery cell body 100 can be squeezed by the flexible adhesive paper 400 and the aluminum-plastic film. The adhesive paper 400 plays a buffering role, thereby reducing the depth of the indentation on the surface of the aluminum-plastic film (i.e., weakening the indentation effect).

[0048] When the battery undergoes a drop test, the indentation on the aluminum-plastic film becomes shallower, significantly reducing the degree of contact, friction, or collision between the film and the outer electrode of the cell. This effectively prevents the outer electrode of the cell from folding or even tearing, thus protecting the separator from damage and preventing short circuits inside the cell, thereby significantly improving the safety and reliability of the battery.

[0049] In some embodiments, refer to Figure 1 and Figure 2 In the width direction of the battery cell body 100, the distance between the adhesive tape 400 and one side of the battery cell body 100 is D1, and the distance between the adhesive tape 400 and the other side of the battery cell body 100 is D2, satisfying: 0mm≤|D1-D2|≤4mm.

[0050] In practical applications, when the adhesive tape 400 is excessively offset, some electrode edges may be exposed, causing indentations to form on the aluminum-plastic film during the hot-pressing process. In this embodiment, the distance between the adhesive tape 400 and one side of the cell body 100 is D1, and the distance between it and the other side is D2, explicitly requiring that 0mm ≤ |D1-D2| ≤ 4mm. For example, |D1-D2|=0mm, or |D1-D2|=2mm, or |D1-D2|=4mm. Taking a cell body 100 width of 65mm and an adhesive tape width of 42mm as an example, D1 can be 11.5mm, D2 can be 11.5mm, and the absolute value of the difference between the two is 0mm; or, D1 can be 12.5mm, D2 can be 10.5mm, and the absolute value of the difference between the two is 2mm, which can be set according to actual needs. This precise distance constraint, from a structural design perspective, ensures the accurate positioning of the adhesive tape 400 in the width direction of the cell body 100, avoiding localized coverage defects caused by excessive offset of the adhesive tape 400, thereby ensuring the safety and reliability of the battery.

[0051] In some embodiments, refer to Figures 1 to 3 The adhesive tape 400 also includes a second adhesive portion 420 corresponding to the first side 121 and a third adhesive portion 430 corresponding to the second side 122;

[0052] In the winding direction of the adhesive tape 400, the length of the second adhesive portion 420 is L1, and the length of the third adhesive portion 430 is L2, satisfying: 0.1mm≤L1≤20mm, 0.1mm≤L2≤20mm, where 0mm≤|L1-L2|≤1mm.

[0053] In this embodiment, the adhesive tape 400, in addition to including a first adhesive portion 410 corresponding to the second end face 112, also includes a second adhesive portion 420 corresponding to the first side face 121 and a third adhesive portion 430 corresponding to the second side face 122. The second adhesive portion 420, the first adhesive portion 410, and the third adhesive portion 430 are sequentially arranged along the length of the adhesive tape 400. In the winding direction of the adhesive tape 400, the length of the second adhesive portion 420 is explicitly defined as L1, and the length of the third adhesive portion 430 is defined as L2, satisfying: 0.1mm≤L1≤20mm, 0.1mm≤L2≤20mm. For example, L1 can be set to 4mm, 8mm, 12mm, or 16mm, and L2 can be set to 5mm, 9mm, 13mm, or 17mm, etc., which can be set according to actual needs. This design ensures that the adhesive tape 400 has sufficient bonding area on the side, guaranteeing the structural stability of the battery cell under various operating conditions. At the same time, it ensures that the adhesive tape 400 wraps around the edges of the electrode sheet of the battery cell body 100, thereby reducing the depth of the indentation on the aluminum-plastic film surface.

[0054] Furthermore, 0mm≤|L1-L2|≤1mm. This setting allows the adhesive tape 400 to form a symmetrical and stable bonding structure on the side of the battery cell when it surrounds the battery cell body 100, avoiding uneven stress caused by large differences in bonding length between the two sides, and enhancing the fixing effect of the adhesive tape 400 on the battery cell body 100.

[0055] In some embodiments, refer to Figures 4 to 6 Multiple through holes 10 are also distributed in the second adhesive portion 420 and the third adhesive portion 430. The multiple through holes 10 on the adhesive tape 400 are not only distributed in the first adhesive portion 410 corresponding to the second end face 112, but also extend to the second adhesive portion 420 corresponding to the first side face 121 and the third adhesive portion 430 corresponding to the second side face 122. This through hole 10 distribution design breaks the limitation of traditional through holes 10 being set only in specific locations, constructing a new adhesive tape 400 structural system.

[0056] From a manufacturing perspective, traditional adhesive tape 400 only has through holes 10 in certain areas. During the punching process, frequent adjustments to equipment parameters are required to adapt to the punching needs of different areas, making the operation complex and prone to errors. In contrast, in this technical solution, the through holes 10 are evenly distributed throughout the entire adhesive tape 400. During the production of adhesive tape 400, a unified punching mold or laser punching parameters can be used, eliminating the need for frequent switching of process settings. This greatly simplifies the production process, reduces the risk of production errors caused by process adjustments, and significantly improves the convenience and efficiency of adhesive tape 400 production.

[0057] In some embodiments, the area ratio of the plurality of through holes 10 to the adhesive tape 400 is 60% to 85%. In this embodiment, the area ratio of the plurality of through holes 10 to the adhesive tape 400 is clearly defined, and the area ratio of the plurality of through holes 10 to the adhesive tape 400 is limited to 60% to 85%. For example, the area ratio of the plurality of through holes 10 to the adhesive tape 400 is 60%, 72.5%, or 85%. This precise ratio setting is an optimal setting obtained after comprehensively considering factors such as electrolyte flow efficiency, structural strength of the adhesive tape 400, and pressure dispersion effect.

[0058] When the area ratio of through-holes 10 is less than 60%, the flow channels of electrolyte within the cell are limited, making it difficult to fully wet all parts of the cell, especially in the end-face area. This leads to a decrease in the utilization rate of electrochemical active materials in the cell, affecting the charge-discharge performance and cycle life. Conversely, when the area ratio of through-holes 10 exceeds 85%, the effective bonding area of ​​the adhesive tape 400 is significantly reduced, decreasing its structural strength and fixation ability. When the cell is subjected to external forces such as heat, pressure, vibration, or impact, the adhesive tape 400 may break or detach, failing to effectively protect the internal structure of the cell. By controlling the area ratio of through-holes 10 to adhesive tape 400 between 60% and 85%, efficient electrolyte flow within the cell can be ensured while maintaining the necessary structural strength and fixation performance of the adhesive tape 400. This, combined with the technical features of the adhesive tape 400, such as the distribution of through-holes 10 throughout the entire area, the limitation of the length of each bonding part, the limitation of the side distance, and the width ratio, further optimizes the overall performance and reliability of the cell.

[0059] In some embodiments, the density of the plurality of through holes 10 distributed on the first adhesive portion 410 is higher than the density of the plurality of through holes distributed on the second adhesive portion 420 and the third adhesive portion 430.

[0060] In this embodiment, based on the functional differences of different parts of the battery cell in actual operation, multiple through holes 10 are distributed differently in the first bonding part 410, the second bonding part 420 and the third bonding part 430, and the density of the through holes 10 on the first bonding part 410 is significantly higher than that on the second and third bonding parts.

[0061] The second end face 112 of the cell body 100 (corresponding to the first bonding portion 410) is a key area for electrolyte flow. During the charging and discharging process, a large amount of electrolyte needs to flow through this area to ensure that the positive and negative electrode active materials react fully with lithium ions. Increasing the density of the through holes 10 at the first bonding portion 410 can significantly increase the number and total area of ​​electrolyte flow channels, reduce the resistance to electrolyte transmission, and enable the electrolyte to more quickly and evenly wet all parts of the cell, effectively improving the ion conduction efficiency and electrochemical activity of the cell. For example, in high-rate charging and discharging scenarios, the densely distributed through holes 10 can ensure timely replenishment of electrolyte and maintain stable performance output of the cell.

[0062] The second adhesive portion 420 and the third adhesive portion 430 primarily function to fix the sides of the battery cell, requiring the adhesive tape 400 to have sufficient adhesive strength to maintain the stability of the battery cell structure. If excessively high-density through-holes 10 are provided in these two areas, it will weaken the solid support area of ​​the adhesive tape 400, reducing the adhesion between the adhesive tape 400 and the battery cell side. When the battery cell is subjected to external forces such as vibration or compression, problems such as adhesive tape detachment and battery cell displacement may occur. Therefore, a lower density design of the through-holes 10 preserves sufficient solid portion of the adhesive tape 400, allowing it to adhere tightly to the battery cell side via pressure-sensitive adhesive, providing stable lateral support and ensuring the battery cell maintains its structural integrity even under complex operating conditions.

[0063] In some embodiments, refer to Figure 3 and Figure 6 Multiple through holes 10 are arranged in an array. In this embodiment, the through holes 10 are arranged in an orderly manner according to a regular row and column pattern. Whether in the first adhesive part 410, the second adhesive part 420, or the third adhesive part 430, the array arrangement principle is followed. Compared with randomly distributed through holes 10, the array arrangement of through holes 10 has stronger regularity and controllability.

[0064] In the first bonding portion 410, the array of through holes 10 can form a regular electrolyte flow network, further optimizing the electrolyte penetration path and improving the electrolyte flow efficiency at the tail of the battery cell; in the second and third bonding portions, the array of through holes 10, with their orderly arrangement, makes the stress distribution of the adhesive tape 400 more uniform when under force, enhancing the fixing effect of the adhesive tape 400 on the side of the battery cell.

[0065] In some embodiments, the spacing between any two adjacent through holes 10 is equal. This equal-spacing design, compared to an array arrangement with non-equal spacing, further enhances the regularity and uniformity of the distribution of the through holes 10, facilitating processing and production by drilling equipment.

[0066] In some embodiments, the through-hole 10 includes at least one of circular, elliptical, sector-shaped, and polygonal shapes. The polygon can be a triangle, square, rectangle, parallelogram, trapezoid, etc., and this embodiment does not limit this. The multiple hole shapes of the through-hole 10 overcome the limitations of traditional single hole shapes and can be selected according to actual needs. For example, as... Figure 1 As shown, the through hole 10 is circular.

[0067] This utility model embodiment also proposes a battery, which includes a casing and a battery cell as described in the foregoing embodiments, with the battery cell disposed within the casing. The specific structure of the battery cell is as described in the foregoing embodiments. Since this battery adopts all the technical solutions of all the foregoing embodiments, it possesses at least all the technical effects brought about by the technical solutions of the foregoing embodiments, and will not be elaborated upon here. The battery can be a lithium battery. Optionally, the battery cell is a wound battery cell.

[0068] The above description is only a part or preferred embodiment of this utility model. Neither the text nor the drawings should limit the scope of protection of this utility model. All equivalent structural transformations made using the content of this utility model specification and drawings under the overall concept of this utility model, or direct / indirect applications in other related technical fields, are included within the scope of protection of this utility model.

Claims

1. A battery cell, characterized in that, include: The battery cell body has a first end face, a second end face, a first side face, and a second side face. The second end face and the first end face are disposed opposite to each other in the length direction of the battery cell body, and the second side face and the first side face are disposed opposite to each other in the thickness direction of the battery cell body. The positive and negative tabs are welded to the battery cell body and extend from the first end face; Adhesive tape is sequentially bonded to the first side surface, the second end surface, and the second side surface to be wrapped around the battery cell body; The adhesive tape includes a first adhesive portion corresponding to the second end face, and the adhesive tape has a plurality of through holes, which are at least distributed in the first adhesive portion. The width ratio of the adhesive tape to the battery cell body is 60% to 70%.

2. The battery cell according to claim 1, characterized in that, In the width direction of the battery cell body, the distance between the adhesive tape and one side of the battery cell body is D1, and the distance between the adhesive tape and the other side of the battery cell body is D2, satisfying: 0mm≤|D1-D2|≤4mm.

3. The battery cell according to claim 1, characterized in that, The adhesive tape also includes a second adhesive portion corresponding to the first side and a third adhesive portion corresponding to the second side; In the winding direction of the adhesive tape, the length of the second adhesive portion is L1 and the length of the third adhesive portion is L2, satisfying: 0.1mm≤L1≤20mm, 0.1mm≤L2≤20mm, where 0mm≤|L1-L2|≤1mm.

4. The battery cell according to claim 3, characterized in that, The plurality of through holes are also distributed in the second adhesive portion and the third adhesive portion.

5. The battery cell according to claim 4, characterized in that, The area ratio of the plurality of through holes to the area of ​​the adhesive paper is 60% to 85%.

6. The battery cell according to claim 4, characterized in that, The density of the plurality of through holes on the first adhesive portion is higher than that on the second adhesive portion and the third adhesive portion.

7. The battery cell according to any one of claims 1 to 6, characterized in that, The multiple through holes are arranged in an array.

8. The battery cell according to claim 7, characterized in that, The spacing between any two adjacent through holes is equal.

9. The battery cell according to any one of claims 1 to 6, characterized in that, The shape of the through hole includes at least one of circular, elliptical, fan-shaped, and polygonal shapes.

10. A battery, characterized in that, It includes a housing and a battery cell as described in any one of claims 1 to 9, wherein the battery cell is disposed within the housing.

Images