Adhesive tape, battery cell and battery
By using adhesive paper with adhesive layer, substrate layer and expansion layer in lithium secondary batteries, the problems of battery fluctuation and drop damage are solved, and the stability and drop performance of the battery cell are improved.
Patent Information
- Application Number
- CN202421204943.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-05-29
- Publication Date
- 2025-02-14
- Estimated Expiration
- 2034-05-29
AI Technical Summary
Lithium secondary batteries are prone to problems such as rising liquid and falling damage during production and use, and the existing glue pasting methods cannot effectively solve these problems.
A glue paper including an adhesive layer, a substrate layer and an expansion layer is used. The adhesive layer is connected to the bare core and an aluminum-plastic film. The expansion layer absorbs excess electrolyte and expands, fills the gap and provides a buffering effect.
It effectively alleviates the problem of liquid fluctuation on the surface of the battery cell, reduces the relative movement of the bare battery cell in the aluminum-plastic film, improves the drop performance of the battery cell, and extends the service life of the battery.
Smart Images
Figure CN222476502U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of batteries, in particular to an adhesive tape, a battery core and a battery. Background Art
[0002] During the manufacturing process of lithium secondary batteries, liquid swelling often occurs, which affects the thickness and appearance of the battery cell. At the same time, if there is a collision or fall during use, it is very easy to cause battery damage, leakage and other problems. In severe cases, the positive and negative pole pieces may be damaged, causing the battery cell performance to deteriorate sharply during use. The general solution to improve the drop performance of the battery cell is to fix the bare battery cell with hot melt glue between the bare battery cell and the aluminum-plastic film to prevent the bare battery cell and the aluminum-plastic film from moving relative to each other when the battery cell falls. However, this glue-sticking method is still not ideal for fixing the bare battery cell. Since the glue-sticking position is significantly higher than other positions, there is still a gap between the bare battery cell and the aluminum-plastic film. After multiple collisions, the bare battery cell is still easy to separate from the outermost aluminum-plastic film and slide. At the same time, this glue-sticking structure cannot solve the problem of liquid swelling of the battery cell. Utility Model Content
[0003] The utility model aims to solve at least one of the technical problems existing in the prior art. To this end, the utility model provides an adhesive tape, which can effectively absorb free electrolyte when attached between a bare battery cell and an aluminum-plastic film, improve the appearance of the battery cell, and fill the gap between the bare battery cell and the aluminum-plastic film, thereby reducing the possibility of relative movement of the bare battery cell in the aluminum-plastic film.
[0004] The utility model also provides a battery core having the adhesive tape.
[0005] The utility model also provides a battery having the battery core.
[0006] The adhesive tape according to the first embodiment of the utility model comprises:
[0007] Adhesive layer;
[0008] A substrate layer, wherein the adhesive layer is disposed on two opposite sides of the substrate layer along its thickness direction;
[0009] The expansion layer is configured to expand at least in the thickness direction after absorbing the electrolyte;
[0010] The expansion layer is provided on at least one side of the substrate layer along its width direction and / or at least one side of the substrate layer along its length direction.
[0011] The adhesive tape according to the embodiment of the utility model has at least the following beneficial effects:
[0012] During the battery cell assembly process, the adhesive tape is connected to the bare battery cell and the aluminum-plastic film through the adhesive layers on both sides of the substrate layer in the thickness direction. After the battery cell is filled with liquid and initially activated, the expansion layer of the adhesive tape absorbs excess electrolyte and expands, thereby alleviating the problem of liquid swelling on the battery cell surface caused by excessive free electrolyte. After expansion, the expansion layer can fill part of the gap between the bare battery cell and the aluminum-plastic film, reducing the possibility of relative movement of the bare battery cell in the aluminum-plastic film. At the same time, the expansion layer can also provide a good buffering effect to prevent external factors such as foreign matter accumulation from damaging the bare battery cell. In the event of a collision, it can effectively disperse the impact force, reduce stress concentration, and improve the drop performance of the battery cell.
[0013] According to some embodiments of the present invention, the expansion layer is provided on two opposite sides of the substrate layer along the width direction.
[0014] According to some embodiments of the present invention, the expansion layer is provided on two opposite sides of the substrate layer along the length direction.
[0015] According to some embodiments of the present invention, the expansion layer is configured such that a dimension of the expansion layer in the thickness direction before expansion is smaller than a dimension of the substrate layer in the thickness direction.
[0016] According to some embodiments of the present invention, a dimension of the expansion layer in the thickness direction is 1 / 3 to 1 / 2 of a dimension of the substrate layer in the thickness direction.
[0017] According to some embodiments of the present invention, the expansion layer is configured such that after expansion, a dimension H1 of the expansion layer in the thickness direction is equal to a dimension H2 of the substrate layer in the thickness direction plus a dimension H3 of the bonding layer in the thickness direction, that is, H1=H2+H3.
[0018] According to some embodiments of the present invention, the dimension of the bonding layer in the thickness direction is 1 / 4 to 1 / 3 of the dimension of the substrate layer in the thickness direction.
[0019] According to some embodiments of the present invention, the expansion layer is provided on at least one side of the substrate layer in the width direction, and the size of the expansion layer in the width direction is 1 / 4 to 1 / 3 of the size of the substrate layer in the width direction.
[0020] The battery cell according to the second embodiment of the utility model includes the adhesive tape described in the first embodiment.
[0021] The battery cell according to the embodiment of the utility model has at least the following beneficial effects:
[0022] By adopting the adhesive tape of the first aspect embodiment of the utility model, the adhesive tape can be attached between the bare battery cell and the aluminum-plastic film of the battery cell, and the expansion layer is used to absorb excess electrolyte and expand, thereby alleviating the problem of liquid swelling on the surface of the battery cell caused by excessive free electrolyte. After expansion, the expansion layer can fill part of the gap between the bare battery cell and the aluminum-plastic film, reducing the possibility of relative movement of the bare battery cell in the aluminum-plastic film. At the same time, the expansion layer can also provide a buffering effect to prevent external force factors such as accumulation of foreign matter from damaging the bare battery cell. When a collision occurs, the impact force can be effectively dispersed, stress concentration can be reduced, and the drop performance of the battery cell can be improved.
[0023] The battery according to the third aspect of the present invention comprises the battery cell described in the second aspect of the present invention.
[0024] The battery according to the embodiment of the utility model has at least the following beneficial effects:
[0025] By adopting the battery cell of the second aspect embodiment of the utility model, and the battery cell adopts the adhesive tape of the first aspect embodiment of the utility model, the adhesive tape can be pasted between the bare battery cell and the aluminum-plastic film of the battery cell, and the expansion layer is used to absorb excess electrolyte and expand, thereby alleviating the problem of liquid swelling on the battery cell surface caused by excessive free electrolyte. After expansion, the expansion layer can fill part of the gap between the bare battery cell and the aluminum-plastic film and provide a buffering effect, thereby improving the drop performance of the battery cell and thus increasing the service life of the battery.
[0026] Additional aspects and advantages of the present invention will be given in part in the following description, and in part will become apparent from the following description, or will be learned through the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS
[0027] The present invention is further described below with reference to the accompanying drawings and embodiments, wherein:
[0028] Figure 1 This is a schematic diagram of the structure of the adhesive tape of one embodiment of the utility model;
[0029] Figure 2 yes Figure 1 A schematic diagram of the structure from another perspective;
[0030] Figure 3 It is a structural schematic diagram of the adhesive tape of another embodiment of the utility model;
[0031] Figure 4 It is a schematic diagram of the structure of the battery cell of an embodiment of the utility model.
[0032] Figure Number:
[0033] Adhesive tape 10, adhesive layer 100, substrate layer 200, expansion layer 300;
[0034] Bare battery cell 20;
[0035] Aluminum plastic film 30. DETAILED DESCRIPTION
[0036] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.
[0037] In the description of the present invention, it should be understood that the descriptions involving orientation, such as the orientation or positional relationship indicated as up, down, etc., are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying 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 on the present invention.
[0038] In the description of the present utility model, "a plurality" means more than two. If there is a description of "first" or "second", it is only for the purpose of distinguishing the technical features, and cannot be understood as indicating or implying the relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the order of the indicated technical features.
[0039] In the description of the present invention, unless otherwise clearly defined, terms such as setting, installing, connecting, etc. should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meanings of the above terms in the present invention based on the specific content of the technical solution.
[0040] Lithium secondary batteries often swell during the manufacturing process, which seriously affects the thickness and appearance of the battery cell. At the same time, if there is a collision or drop during use, it is very easy to cause battery damage, leakage and other problems. In severe cases, the positive and negative poles may be damaged, causing the battery performance to deteriorate sharply during use, and the isolation membrane may be damaged, causing the positive and negative poles to short-circuit, causing the battery cell to heat up, catch fire, explode and other safety accidents. Therefore, improving the battery cell drop performance is a very important part of the battery design process; in the related technology, the solution to improve the battery cell drop performance Hot melt adhesive is applied on the back of the battery cell (between the bare battery cell and the aluminum-plastic film) to fix the bare battery cell so as to prevent relative movement between the bare battery cell and the aluminum-plastic film when the battery cell falls. However, this adhesive bonding method is still not ideal for fixing the bare battery cell, especially when the battery cell is heavy. Since the force applied to the bare battery cell is different from that applied to the hot melt adhesive and the aluminum-plastic film, the bare battery cell is subjected to a greater force and there is a gap between the bare battery cell and the aluminum-plastic film. After multiple collisions, the bare battery cell is still easy to separate from the outermost aluminum-plastic film and slide. The drop performance still needs to be improved. In addition, this adhesive bonding structure cannot solve the problem of liquid swelling on the surface of the battery cell.
[0041] Therefore, the utility model provides a tape, a battery cell and a battery, which can effectively improve the above problems.
[0042] Reference below Figures 1 to 4 The adhesive tape, the battery cell and the battery according to the embodiments of the utility model are described.
[0043] The adhesive tape 10 according to the first embodiment of the utility model includes: an adhesive layer 100 , a substrate layer 200 and an expansion layer 300 .
[0044] For example, the substrate layer 200 is used to place the bonding layer 100 and the expansion layer 300 , and the substrate layer 200 can provide adhesion support for the bonding layer 100 and the expansion layer 300 .
[0045] The substrate layer 200 is provided with adhesive layers 100 on opposite sides along its thickness direction, that is, the adhesive layer 100 is provided with two layers, which are respectively attached to the two surfaces of the substrate layer 200 in the thickness direction. When the adhesive tape 10 is used for the battery cell, one adhesive layer 100 is used for bonding and connecting with the bare battery cell 20, and the other adhesive layer 100 is used for bonding and connecting with the aluminum-plastic film 30. It can be imagined that, taking the adhesive layer 100 on one side in the thickness direction of the substrate layer 200 as an example, the structure of the adhesive layer 100 can have at least the following three forms A / B / C:
[0046] A. The bonding layer 100 is an integrated structure, and the projection of the bonding layer 100 in the thickness direction coincides with the projection of the substrate layer 200 in the thickness direction;
[0047] B. The adhesive layer 100 is an integrated structure, the projection area of the adhesive layer 100 in the thickness direction is smaller than the projection area of the substrate layer 200 in the thickness direction, and the edge of the adhesive layer 100 does not extend beyond the edge of the substrate layer 200;
[0048] C. The adhesive layer 100 is a split structure. At least two adhesive layers 100 are provided and distributed at intervals. The projected area of the adhesive layer 100 in the thickness direction is smaller than the projected area of the substrate layer 200 in the thickness direction, and the edge of the adhesive layer 100 does not extend beyond the edge of the substrate layer 200.
[0049] The substrate layer 200 is provided with an expansion layer 300 on at least one side along its width direction and / or at least one side along its length direction. The expansion layer 300 is configured to expand at least in the thickness direction after absorbing the electrolyte. When the adhesive tape 10 is bonded between the bare battery cell 20 and the aluminum-plastic film 30 and the battery cell is injected and initially activated, the expansion layer 300 can absorb excess electrolyte and expand to fill part of the gap between the bare battery cell 20 and the aluminum-plastic film 30. It should be understood that the expansion layer 300 can not only expand in the thickness direction but also in the width direction after absorbing the electrolyte, but the expansion layer 300 mainly relies on expansion in the thickness direction to fill the gap between the bare battery cell 20 and the aluminum-plastic film 30.
[0050] In the present embodiment, when the adhesive tape 10 is applied to the battery cell, during the battery cell assembly process, the adhesive tape 10 is respectively connected to the bare battery cell 20 and the aluminum-plastic film 30 through the adhesive layers 100 on both sides of the substrate layer 200 in the thickness direction. After the battery cell is filled with liquid and initially activated, the expansion layer 300 of the adhesive tape 10 can absorb excess electrolyte and expand, thereby alleviating the problem of liquid swelling on the surface of the battery cell caused by excessive free electrolyte. After expansion, the expansion layer 300 can fill part of the gap between the bare battery cell 20 and the aluminum-plastic film 30, reducing the possibility of relative movement of the bare battery cell 20 in the aluminum-plastic film 30. At the same time, the expansion layer 300 can also provide a good buffering effect to prevent external force factors such as foreign matter accumulation from damaging the bare battery cell 20. When a collision occurs, the impact force can be effectively dispersed, stress concentration can be reduced, and the drop performance of the battery cell can be improved.
[0051] In the embodiment of the utility model, the function of the substrate layer 200 is to provide an adhesion layer for the bonding layer 100 and the expansion layer 300. The substrate layer 200 can be made of thermoplastic material or rubber compound, such as PP (polypropylene), PU (polyurethane), POM (polyoxymethyl ester), etc.; the function of the bonding layer 100 is to provide viscosity. The material of the bonding layer 100 can be selected from styrene-butadiene rubber, polyisoprene rubber, polyisobutylene, butyl rubber, chloroprene rubber, nitrile rubber, etc., and can be combined with additives such as tackifying resin, softener, antioxidant, etc., and can also be selected from the like. The bonding layer 100 is made of high molecular polymers such as polyacrylate, polyurethane, polyvinyl chloride, polyvinyl ether, etc.; the expansion layer 300 mainly absorbs excess electrolyte to expand, and the material of the expansion layer 300 can be selected from hydrophilic polymers such as PVA (polyvinyl alcohol), PAA (polyacrylic acid), hydrogel, etc., and the affinity for the electrolyte is improved through certain modification measures, and the absorption capacity of the electrolyte is improved; the specific materials of the substrate layer 200, the bonding layer 100, and the expansion layer 300 can be selected according to actual conditions, and the above materials are only for reference.
[0052] In an embodiment of the present utility model, when manufacturing the adhesive tape 10, a substrate layer solution and an expansion layer solution of a certain concentration are first prepared, and a volatile material or a photosensitive material (easily decomposed by light) is added to the expansion layer solution and evenly dispersed in the solution. The two solutions are applied together in a coating-like manner by adjusting the flow rate, and the solution is solidified by high-temperature curing or a method similar to UV curing. At the same time, the volatile substances in the expansion layer solution are evaporated to form a porous fluffy structure in the expansion layer 300, thereby completing the composite of the substrate layer 200 and the expansion layer 300, and then the adhesive layer 100 is coated on the two surfaces of the substrate layer 200 in the thickness direction.
[0053] In some embodiments of the utility model, the expansion layer 300 is provided on opposite sides of the substrate layer 200 in the width direction. It can be understood that the adhesive tape 10 of the present embodiment is in the shape of a long strip. The expansion layer 300 is provided on opposite sides of the substrate layer 200 in the width direction so that the expansion layer 300 has a sufficient length to fully absorb the excess electrolyte and expand, thereby filling more of the gap between the bare battery 20 and the aluminum-plastic film 30, and the expansion layers 300 on both sides absorb the electrolyte and expand at the same time, and the flatness is high. It can be understood that, in order to facilitate manufacturing and to improve the effect of absorbing the electrolyte, the two ends of the expansion layer 300 in the width direction of the substrate layer 200 in the length direction are aligned with the two ends of the substrate layer 200 in the length direction.
[0054] It should be noted that, on the basis of setting the expansion layer 300 on the opposite sides of the substrate layer 200 in the width direction, the expansion layer 300 can be set on the side of the substrate layer 200 in the length direction, or the expansion layer 300 can be not set; when the expansion layer 300 is set on one or both sides in the length direction of the substrate layer 200, the absorption effect of excess electrolyte is better, and the gap between the bare battery cell 20 and the aluminum-plastic film 30 can be better filled, and the possibility of relative sliding of the bare battery cell 20 in the aluminum-plastic film 30 is reduced to a greater extent; and when the expansion layer 300 is not set on both sides in the length direction of the substrate layer 200, it is easier to realize in manufacturing, and a longer adhesive tape 10 can be produced at one time and then cut during manufacturing, and the expansion backlog of the expansion layer 300 on the substrate layer 200 and the adhesive layer 100 when it expands is also relatively small. In one specific embodiment, expansion layers 300 are provided on both sides of the substrate layer 200 along the width direction and on both sides of the substrate layer 200 along the length direction, that is, expansion layers 300 are provided all around the substrate layer 200. This structural form has a good effect on absorbing excess electrolyte and can fill more gaps. In addition, simultaneous expansion all around can better ensure the flatness of the battery cell surface.
[0055] In some embodiments of the present invention, the expansion layer 300 is configured to have a size in the thickness direction before expansion that is smaller than the size in the thickness direction of the substrate layer 200, so that it is not only convenient for production and manufacturing, but also can ensure that the expansion layer 300 is fully expanded to fill the gap between the bare battery cell 20 and the aluminum-plastic film 30 at a lower cost. It can be understood that, in order to facilitate the composite manufacturing of the substrate layer 200 and the expansion layer 300, one side surface of the expansion layer 300 along the thickness direction is flush with one side surface of the substrate layer 200 along the thickness direction.
[0056] In some specific embodiments, the size of the expansion layer 300 in the thickness direction is 1 / 3 to 1 / 2 of the size of the substrate layer 200 in the thickness direction. For example, the size of the expansion layer 300 in the thickness direction can be 1 / 3, 5 / 12 or 1 / 2 of the size of the substrate layer 200 in the thickness direction. When the size of the expansion layer 300 in the thickness direction is less than 1 / 3 of the size of the substrate layer 200 in the thickness direction, the expansion layer 300 may not fully absorb excess electrolyte and the effect of filling the gap is poor. When the size of the expansion layer 300 in the thickness direction is greater than 1 / 2 of the size of the substrate layer 200 in the thickness direction, the manufacturing cost will be increased and material waste will be easily caused, that is, the thickness that the expansion layer 300 can expand exceeds the expansion thickness required to fill the excess gap. Considering the effect and cost of absorbing electrolyte, the ratio range of 1 / 3 to 1 / 2 is selected.
[0057] In some embodiments of the present invention, the expansion layer 300 is configured such that after expansion, the dimension H1 in the thickness direction is equal to the dimension H2 in the thickness direction of the substrate layer 200 plus the dimension H3 in the thickness direction of the adhesive layer 100, that is, H1=H2+H3. In this way, when the adhesive tape 10 is applied to the battery cell, the expansion layer 300 can fully fill the gap between the bare battery cell 20 and the aluminum-plastic film 30 after expansion.
[0058] In some embodiments of the present invention, the size of the adhesive layer 100 in the thickness direction is 1 / 4 to 1 / 3 of the size of the substrate layer 200 in the thickness direction. For example, the size of the adhesive layer 100 in the thickness direction can be 1 / 4, 7 / 24 or 1 / 3 of the size of the substrate layer 200 in the thickness direction; when the size of the adhesive layer 100 in the thickness direction is less than 1 / 4 of the size of the substrate layer 200 in the thickness direction, the adhesive layer 100 may not provide sufficiently strong adhesion, so that the adhesive layer 100 is easily detached from the aluminum-plastic film 30 or the bare battery cell 20, and when the size of the adhesive layer 100 in the thickness direction is greater than 1 / 3 of the size of the substrate layer 200 in the thickness direction, the cost will increase, and the overall thickness of the adhesive tape 10 may be too large, thereby affecting the flatness of the battery cell surface. Taking the above two factors into consideration, the ratio range of 1 / 4 to 1 / 3 is selected.
[0059] In some embodiments of the present invention, the substrate layer 200 is provided with an expansion layer 300 on at least one side in the width direction. In this embodiment, the adhesive tape 10 is in the shape of a long strip. The expansion layer 300 is provided on at least one side in the width direction of the substrate layer 200 so that the expansion layer 300 has a sufficient length to fully absorb the electrolyte and expand, thereby filling more of the gap between the bare battery core 20 and the aluminum-plastic film 30. Further, the size of the expansion layer 300 in the width direction is 1 / 4 to 1 / 3 of the size of the substrate layer 200 in the width direction. For example, the expansion layer 300 in the width direction is The size of the expansion layer 300 in the width direction can be 1 / 4, 7 / 24 or 1 / 3 of the size of the substrate layer 200 in the width direction. When the size of the expansion layer 300 in the width direction is less than 1 / 4 of the size of the substrate layer 200 in the width direction, the expansion layer 300 may not fully absorb excess electrolyte. When the size of the expansion layer 300 in the width direction is greater than 1 / 3 of the size of the substrate layer 200 in the width direction, on the one hand, the cost will increase, and on the other hand, the expansion layer 300 being too wide may also affect the overall flatness of the battery cell. After comprehensive consideration, the ratio range of 1 / 4 to 1 / 3 is selected. It should be noted that the above-mentioned size ratio relationship in this embodiment is only for the expansion layer 300 located in the width direction of the substrate layer 200.
[0060] The battery cell according to the second embodiment of the utility model includes the adhesive tape 10 of the first embodiment.
[0061] For example, Figure 4 As shown, the battery cell can also include a bare battery cell 20 and an aluminum-plastic film 30, wherein the aluminum-plastic film 30 is located at the periphery of the bare battery cell 20, and the adhesive tape 10 is located between the bare battery cell 20 and the aluminum-plastic film 30, wherein the adhesive layers 100 on both sides of the substrate layer 200 are respectively bonded to the bare battery cell 20 and the aluminum-plastic film 30, thereby connecting the bare battery cell 20 and the aluminum-plastic film 30. It can be imagined that one or more adhesive tapes 10 can be set between the aluminum-plastic film 30 and the bare battery cell 20, and the specific number is selected according to actual usage requirements.
[0062] The battery cell adopts the adhesive tape 10 of the first aspect of the utility model embodiment. The adhesive tape 10 can be attached between the bare battery cell 20 and the aluminum-plastic film 30 of the battery cell. The expansion layer 300 is used to absorb excess electrolyte and expand, thereby alleviating the problem of liquid swelling on the surface of the battery cell caused by excessive free electrolyte. After expansion, the expansion layer 300 can fill part of the gap between the bare battery cell 20 and the aluminum-plastic film 30, reducing the possibility of relative movement of the bare battery cell 20 in the aluminum-plastic film 30. At the same time, the expansion layer 300 can also provide a buffering effect to prevent external force factors such as foreign matter accumulation from damaging the bare battery cell 20. When a collision occurs, the impact force can be effectively dispersed, stress concentration can be reduced, and the drop performance of the battery cell can be improved.
[0063] It should be noted that, since the battery cell can adopt all the technical solutions of the adhesive tape 10 of the first embodiment, it at least has all the beneficial effects brought by the technical solutions of the first embodiment, and these additional beneficial effects will not be repeated here.
[0064] It is understandable that other structures and operations of the battery cell according to the embodiment of the utility model are known to ordinary technicians in the field and will not be described in detail here.
[0065] A battery according to an embodiment of the third aspect of the utility model includes a battery cell according to the embodiment of the second aspect.
[0066] The battery adopts the battery cell of the second embodiment of the utility model, and the battery cell adopts the adhesive tape 10 of the first embodiment of the utility model. The adhesive tape 10 can be attached between the bare battery cell 20 and the aluminum-plastic film 30 of the battery cell. The expansion layer 300 absorbs excess electrolyte and expands to alleviate the problem of liquid swelling on the surface of the battery cell caused by excessive free electrolyte. After expansion, the expansion layer 300 can fill part of the gap between the bare battery cell 20 and the aluminum-plastic film 30 and provide a buffering effect, thereby improving the drop performance of the battery cell and thus improving the service life of the battery.
[0067] It should be noted that, since the battery can adopt all the technical solutions of the adhesive tape 10 of the first embodiment, it at least has all the beneficial effects brought by the technical solutions of the first embodiment, and these additional beneficial effects will not be repeated here.
[0068] It is understandable that other structures and operations of the battery according to the embodiment of the utility model are known to ordinary technicians in the field and will not be described in detail here.
[0069] The embodiments of the present invention are described in detail above in conjunction with the accompanying drawings, but the present invention is not limited to the above embodiments, and various changes can be made within the knowledge scope of ordinary technicians in the relevant technical field without departing from the purpose of the present invention.
Claims
1. A tape, characterized in that: include: Adhesive layer; A substrate layer, wherein the adhesive layer is disposed on two opposite sides of the substrate layer along its thickness direction; The expansion layer is configured to expand at least in the thickness direction after absorbing the electrolyte; The expansion layer is provided on at least one side of the substrate layer along its width direction and / or at least one side of the substrate layer along its length direction.
2. The adhesive tape according to claim 1, characterized in that: The expansion layers are disposed on opposite sides of the substrate layer along the width direction.
3. The adhesive tape according to claim 2, characterized in that: The expansion layers are disposed on opposite sides of the substrate layer along the length direction.
4. The adhesive tape according to claim 1, characterized in that: The expansion layer is configured such that a dimension in the thickness direction before expansion is smaller than a dimension of the base material layer in the thickness direction.
5. The adhesive tape according to claim 4, characterized in that: The size of the expansion layer in the thickness direction is 1 / 3 to 1 / 2 of the size of the base material layer in the thickness direction.
6. The adhesive tape according to claim 4, characterized in that: The expansion layer is configured such that after expansion, a dimension H1 of the expansion layer in the thickness direction is equal to a dimension H2 of the base material layer in the thickness direction plus a dimension H3 of the adhesive layer in the thickness direction, that is, H1=H2+H3.
7. The adhesive tape according to claim 1, characterized in that: The dimension of the adhesive layer in the thickness direction is 1 / 4 to 1 / 3 of the dimension of the base material layer in the thickness direction.
8. The adhesive tape according to claim 1, characterized in that: The expansion layer is provided on at least one side of the substrate layer in the width direction, and a size of the expansion layer in the width direction is 1 / 4 to 1 / 3 of a size of the substrate layer in the width direction.
9. A battery cell, characterized in that: The method comprises the adhesive tape as claimed in any one of claims 1 to 8.
10. A battery, characterized in that: Comprising the battery cell as claimed in claim 9.