A soft-pack casing and battery
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-08-21
- Publication Date
- 2026-08-11
AI Technical Summary
[0005]本实用新型提供一种软包外壳及电池，主要解决现有电池当极耳弯折时易与软包外壳的金属层接触而引发短路的技术问题
[0018]本方案在软包外壳相对的第一端部和第二端部都设置绝缘的封边结构，并具体将封边结构设置在金属层(目前金属层优选为铝箔层)的外侧，通过封边结构对金属层遮盖，从而防止金属层暴露于外界，又由于封边结构具有绝缘性，因此从软包外壳向外引出的极耳即使弯折也不会和金属层接触，进而防止电池发生短路。此外，本方案由于可以防止电池发生短路，因此采用本方案后可以减少原来在极耳位置贴绝缘胶纸的生产工序，从而在降低电池发生短路风险的同时还有利于提高电池的生产效率。
Smart Images
Figure CN224625857U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the technical field of batteries, and in particular to a soft-pack casing and a battery. Background Technology
[0002] Existing pouch batteries consist of a battery cell and a pouch casing. The pouch casing is typically made of aluminum-plastic film and is used to enclose the battery cell. The positive and negative terminals connected to the battery cell extend outwards relative to the pouch casing to expose the positive and negative electrodes. After enclosing the battery cell, the outer edges are heat-sealed to seal the cell internally, preventing electrolyte leakage and the entry of external substances. More specifically, most existing pouch casings include, from the outside in, a nylon layer, an aluminum foil layer, and an insulating heat-sealed layer. This type of pouch casing is also known in the art as an aluminum-plastic film. The nylon layer protects the middle aluminum foil layer from mechanical scratches or punctures, reduces external impact, blocks oxygen penetration, and maintains the deformation capacity of the aluminum foil layer. The core function of the aluminum foil layer is as a shielding layer, shielding it from external magnetic fields that interfere with the charging and discharging of the internal battery cell. Furthermore, the oxide film formed by the reaction of metallic aluminum with oxygen can prevent moisture from entering. The aluminum foil layer, penetrating into the battery cell, also provides structural rigidity to support the entire soft-pack outer shell, which can be stamped to form a pit for placing the battery cell. The insulating hot-pressed layer is mostly made of cast polypropylene (CPP) or polypropylene (PP). The insulating hot-pressed layer has the property of being resistant to electrolyte corrosion to prevent the electrolyte from contacting the metal layer. At the same time, the insulating hot-pressed layer has the property of being heat-melted at high temperatures, so that a sealing edge can be formed on the periphery of the battery cell after hot pressing. The insulating hot-pressed layer made of CPP or PP material has high insulation and puncture resistance.
[0003] Please see Figure 1 After the battery cell is wrapped in the soft-pack casing 2, the positive tab 3 or negative tab 4 usually needs to be bent and then a protective plate is glued on. When the positive tab 3 or negative tab 4 is bent, it is easy to come into contact with the sealing edge 20 of the soft-pack casing 2. The aluminum foil layer at the edge of the sealing edge 20 is exposed outward. Therefore, the positive tab 3 or negative tab 4 is easy to come into contact with the aluminum foil layer during the bending process, which can easily cause a short circuit. The current solution is to stick an insulating tape on the short-circuit-prone position before assembling the protective plate. However, there is still an uncontrollable aspect to sticking the insulating tape. That is, there is still a risk that the tab will come into contact with the aluminum foil layer inside the soft-pack casing. Therefore, the existing soft-pack casing needs to be improved.
[0004] The above information is provided as background information only to aid in understanding this disclosure and does not constitute an assertion or admission that any of the above content can be used as prior art relative to this disclosure. Utility Model Content
[0005] This utility model provides a soft-pack casing and a battery, which mainly solves the technical problem that existing batteries are prone to short circuits when the tabs are bent and come into contact with the metal layer of the soft-pack casing.
[0006] To achieve the above objectives, this utility model provides the following technical solution:
[0007] A flexible housing for enclosing a battery cell, the flexible housing comprising an outer resistance layer, a metal layer and an insulating hot-pressed layer arranged sequentially from the outside to the inside, the flexible housing having insulating edge sealing structures at least at a first end and a second end opposite to each other, the edge sealing structures at the first end and the second end being located outside the metal layer to cover the metal layer.
[0008] In one of the technical solutions, the insulating hot-pressed layer is bent toward the outer barrier layer at at least one of the first end and the second end to form a first bent portion that covers the metal layer, and the sealing structure includes the first bent portion.
[0009] In one of the technical solutions, the outer barrier layer is bent toward the insulating hot-pressed layer at at least one of the first end and the second end to form a second bent portion that covers the metal layer, and the sealing structure includes the second bent portion.
[0010] In one of the technical solutions, the insulating hot-pressed layer is bent toward the outer barrier layer at at least one of the first end and the second end to form a first bent portion covering the metal layer, and the outer barrier layer is correspondingly bent toward the insulating hot-pressed layer at at least one of the first end and the second end to form a second bent portion covering the metal layer, and the first bent portion and the second bent portion are connected to form the sealing structure.
[0011] In one of the technical solutions, the sealing structure includes an insulating layer disposed between the outer resistance layer and the insulating hot-pressed layer and located outside the metal layer.
[0012] In one of the technical solutions, the edge sealing structure includes a U-shaped edge banding member, which covers the first end or the second end to cover the metal layer.
[0013] In one of the technical solutions, the outer resistance layer is a nylon layer, the metal layer is an aluminum foil layer, and the insulating hot-pressed layer is a cast polypropylene layer or a polypropylene layer.
[0014] In one of the technical solutions, a first adhesive layer is bonded between the outer resist layer and the metal layer, and a second adhesive layer is bonded between the metal layer and the insulating hot-pressed layer.
[0015] In one of the technical solutions, the width of the edge sealing structure is not less than 0.2 mm and not more than 1 mm.
[0016] This application also provides a battery, including a battery cell and the aforementioned soft-pack casing. The battery cell has at least two tabs with opposite polarities. The first end and the second end of the soft-pack casing are folded to wrap around the battery cell, and the first end and the second end of the soft-pack casing together wrap around at least one of the tabs and are respectively sealed to the tabs.
[0017] Compared with the prior art, the soft-pack shell provided by this utility model has at least the following beneficial effects:
[0018] This design incorporates insulating edge-sealing structures at both the first and second opposite ends of the soft-pack outer casing. Specifically, these edge-sealing structures are positioned on the outside of the metal layer (currently, an aluminum foil layer is preferred). By covering the metal layer with these structures, the metal layer is prevented from being exposed to the outside environment. Furthermore, due to the insulating nature of the edge-sealing structure, the tabs extending from the soft-pack outer casing will not come into contact with the metal layer even when bent, thus preventing short circuits. In addition, because this design prevents short circuits, it reduces the production step of applying insulating tape to the tabs, thereby lowering the risk of short circuits and improving battery production efficiency. Attached Figure Description
[0019] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0020] Figure 1 This is a schematic diagram of the structure of an existing battery;
[0021] Figure 2 This is a schematic diagram of a first structure of a soft-pack shell provided in an embodiment of this application;
[0022] Figure 3 This is a schematic diagram of a second structure of the soft-pack shell provided in the embodiments of this application;
[0023] Figure 4 This is a schematic diagram of a third structure of the soft-pack shell provided in an embodiment of this application;
[0024] Figure 5 This is a schematic diagram of a fourth structure of the soft-pack shell provided in the embodiments of this application;
[0025] Figure 6A schematic diagram of a fifth structure of the soft-pack shell provided in the embodiments of this application;
[0026] Figure 7 This application provides an internal structure diagram of a battery according to an embodiment of the present application.
[0027] Figure 8 for Figure 7 A magnified view of a portion of point A in the middle.
[0028] Figure label:
[0029] 1. Battery cell; 2. Soft-pack outer casing; 20. Sealing edge; 21. Outer resistance layer; 211. Second bend; 22. Metal layer; 23. Insulating hot-pressed layer; 231. First bend; 24. First end; 25. Second end; 26. Sealing structure; 27. Insulating layer; 28. U-shaped edge banding; 29. First adhesive layer; 30. Second adhesive layer; 3. Positive tab; 4. Negative tab; 5. Hot melt adhesive. Detailed Implementation
[0030] To make the technical problems, technical solutions, and beneficial effects to be solved by this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and are not intended to limit the scope of this application.
[0031] It should be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on or indirectly on that other component. When a component is referred to as being "connected to" another component, it can be directly connected to or indirectly connected to that other component.
[0032] It should be understood that the terms "upper", "lower", "top", "bottom", "inner", "outer", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.
[0033] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.
[0034] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments.
[0035] Please refer to the following: Figure 2 , Figure 7 and Figure 8 This utility model embodiment provides a soft-pack shell 2 for wrapping the battery cell 1. The soft-pack shell 2 specifically includes an outer resistance layer 21, a metal layer 22, and an insulating hot-pressed layer 23 arranged sequentially from the outside in. The outer resistance layer 21 is primarily made of nylon (NY) or polyethylene terephthalate (PET). Its function is to protect the intermediate metal layer 22 from mechanical scratches or punctures, while also mitigating external impacts, blocking oxygen penetration, and maintaining the deformation capability of the metal layer 22. The metal layer 22 is mostly made of 35μm-40μm aluminum foil. Its core function is to act as a shielding layer, shielding the battery cell 1 from interference from external magnetic fields during charging and discharging. Furthermore, when the metal layer 22 is made of aluminum foil, the oxide film generated by the reaction of aluminum with oxygen can prevent moisture from penetrating into the battery cell 1. The metal layer 22 also provides structural rigidity to support the entire soft-pack outer shell 2, which can be stamped to form a pit for placing the battery cell. The insulating hot-pressed layer 23 is mostly made of cast polypropylene (CPP) or polypropylene (PP). The insulating hot-pressed layer 23 has the property of being resistant to electrolyte corrosion to prevent electrolyte from contacting the metal layer 22. At the same time, the insulating hot-pressed layer 23 has the property of being heat-melted at high temperature so that a sealing edge 20 can be formed on the periphery of the battery cell 1 after hot pressing. The insulating hot-pressed layer 23 made of CPP or PP material has high insulation and puncture resistance.
[0036] Please refer to the following: Figure 2 , Figure 7 and Figure 8 The soft-pack casing 2 has insulating edge-sealing structures 26 at least on its opposite first end 24 and second end 25. These edge-sealing structures 26 are located outside the metal layer 22 to cover it, preventing the edges of the metal layer 22 from being exposed. Because these edge-sealing structures 26 are insulating, the positive tab 3 or negative tab 4 extending outwards from the soft-pack casing 2 will not contact the metal layer 22 even if bent, thus preventing a short circuit. Furthermore, since this solution prevents short circuits, it reduces the production process of applying insulating tape to the tabs, thereby lowering the risk of short circuits and improving battery production efficiency.
[0037] The edge sealing structure 26 can be designed in the following five ways:
[0038] Method 1: For example Figure 2As shown, the insulating hot-pressed layer 23 is bent toward the outer barrier layer 21 at at least one of the first end 24 and the second end 25 to form a first bent portion 231 that covers the metal layer 22, and the sealing structure 26 is designed to include this first bent portion 231. When both the first end 24 and the second end 25 are provided with the first bent portion 231, the insulating hot-pressed layer 23 is equivalent to providing a groove structure for accommodating the metal layer 22;
[0039] Method 2: For example Figure 3 As shown, the outer barrier layer 21 is bent toward the insulating hot-pressed layer 23 at at least one of the first end 24 and the second end 25 to form a second bent portion 211 that covers the metal layer 22, and the sealing structure 26 is designed to include this second bent portion 211. When both the first end 24 and the second end 25 are provided with the second bent portion 211, the outer barrier layer 21 is equivalent to providing a groove structure for accommodating the metal layer 22;
[0040] Method 3: For example Figure 4 As shown, the insulating hot-pressed layer 23 is bent toward the outer barrier layer 21 at at least one of the first end 24 and the second end 25 to form a first bent portion 231 covering the metal layer 22. The outer barrier layer 21 is bent toward the insulating hot-pressed layer 23 at at least one of the first end 24 and the second end 25 to form a second bent portion 211 covering the metal layer 22. Moreover, the first bent portion 231 and the second bent portion 211 are connected to form the aforementioned sealing structure 26. When the first end 24 and the second end 25 are respectively provided with the first bent portion 231 and the second bent portion 211, the outer barrier layer 21 is equivalent to having a groove structure that accommodates half of the metal layer 22, and the insulating hot-pressed layer 23 is equivalent to having a groove structure that accommodates the other half of the metal layer 22.
[0041] Method 4: For example Figure 5 As shown, the sealing structure 26 may include an insulating layer 27 disposed between the outer resist layer 21 and the insulating hot-pressed layer 23 and located outside the metal layer 22. The insulating layer 27 can be laminated between the outer resist layer 21 and the insulating hot-pressed layer 23 by hot pressing or adhesive bonding.
[0042] Method 5: For example Figure 6 As shown, the edge sealing structure 26 may include a U-shaped edge banding member 28, which covers the first end 24 or the second end 25 to cover the metal layer 22. The U-shaped edge banding member 28 can be connected to the surface of the outer barrier layer 21 and the surface of the insulating hot-pressed layer 23 by hot pressing or adhesive bonding, respectively.
[0043] This section further explains that at least one of the five edge-sealing structures 26 described above can be used on the first end 24 of the soft-pack outer shell 2, and at least one of the five edge-sealing structures 26 described above can also be used on the second end 25 of the soft-pack outer shell 2. In this embodiment, preferably, the edge-sealing structure 26 uses only the first method described above on both the first end 24 and the second end 25 of the soft-pack outer shell 2. Furthermore, please refer to... Figure 8 The width L of the edge sealing structure 26 is designed to be no less than 0.2mm and no more than 1mm. Please refer to [link / reference]. Figures 2 to 8 Preferably, a first adhesive layer 29 is bonded between the outer resist layer 21 and the metal layer 22, and a second adhesive layer 30 is bonded between the metal layer 22 and the insulating hot-pressed layer 23. The adhesive bonding method makes it easier to connect the two-layer structure and has the advantage of lower manufacturing cost.
[0044] Please refer to the following: Figure 7 and Figure 8 This embodiment also provides a battery, which includes a battery cell 1 and the aforementioned soft-pack casing 2. The battery cell 1 has at least two tabs of opposite polarity (i.e., at least one positive tab 3 and at least one negative tab 4). After manufacturing the outer battery cell 1, the first end 24 and the second end 25 of the soft-pack casing 2 need to be folded and wrapped around the battery cell 1. At least one of the positive tab 3 or the negative tab 4 extends outward relative to the first end 24 and the second end 25; that is, the first end 24 and the second end 25 together wrap around the portion of the tab. Typically, the tab and the first end 24 are separated by a [missing information - likely a typo]. Hot melt adhesive 5 needs to be pre-applied between the tab and the second end 25. After hot pressing the first end 24 and the second end 25, the insulating hot-pressed layer 23 in the first end 24 and the insulating hot-pressed layer 23 in the second end 25 can be fused together, and the hot melt adhesive 5 can be cured to form a sealing edge 20. This sealing edge 20 actually seals the gap between the tab and the soft-pack shell 2, preventing the internal electrolyte from leaking out from the gap between the tab and the soft-pack shell 2, and also preventing external substances from entering the cell 1 from the gap between the tab and the soft-pack shell 2. Since the battery of this embodiment uses the aforementioned soft-pack shell 2, the tab of the battery of this embodiment will not come into contact with the metal layer 22 even if it is bent. That is, the battery of this embodiment has the advantage of low short-circuit risk during the manufacturing process, which can greatly improve the battery's yield rate.
[0045] The above are merely preferred embodiments of the present utility model, and only specifically describe the technical principles of the present utility model. These descriptions are only for explaining the principles of the present utility model and should not be construed as limiting the scope of protection of the present utility model in any way. Based on this explanation, any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present utility model, as well as other specific embodiments of the present utility model that can be conceived by those skilled in the art without creative effort, should be included within the scope of protection of the present utility model.
Claims
1. A flexible housing for enclosing a battery cell, characterized in that, The flexible housing includes an outer barrier layer, a metal layer, and an insulating hot-pressed layer arranged sequentially from the outside to the inside. The flexible housing has insulating edge sealing structures at least at a first end and a second end, and the edge sealing structures at the first end and the second end are located outside the metal layer to cover the metal layer.
2. The soft-pack outer shell as described in claim 1, characterized in that, The insulating hot-pressed layer is bent toward the outer barrier layer at at least one of the first end and the second end to form a first bent portion that covers the metal layer, and the sealing structure includes the first bent portion.
3. The soft-pack outer shell as described in claim 1, characterized in that, The outer barrier layer is bent toward the insulating hot-pressed layer at at least one of the first end and the second end to form a second bent portion that covers the metal layer, and the sealing structure includes the second bent portion.
4. The soft-pack outer shell as described in claim 1, characterized in that, The insulating hot-pressed layer is bent toward the outer barrier layer at at least one of the first end and the second end to form a first bent portion covering the metal layer, and the outer barrier layer is correspondingly bent toward the insulating hot-pressed layer at at least one of the first end and the second end to form a second bent portion covering the metal layer, and the first bent portion and the second bent portion are connected to form the sealing structure.
5. The soft-pack outer shell as described in claim 1, characterized in that, The sealing structure includes an insulating layer disposed between the outer barrier layer and the insulating hot-pressed layer and located outside the metal layer.
6. The soft-pack outer shell as described in claim 1, characterized in that, The edge sealing structure includes a U-shaped edge banding member, which covers the first end or the second end to conceal the metal layer.
7. The soft-pack outer shell as described in any one of claims 1-6, characterized in that, The outer barrier layer is a nylon layer, the metal layer is an aluminum foil layer, and the insulating hot-pressed layer is a cast polypropylene layer or a polypropylene layer.
8. The soft-pack outer shell as described in any one of claims 1-6, characterized in that, A first adhesive layer is bonded between the outer resist layer and the metal layer, and a second adhesive layer is bonded between the metal layer and the insulating hot-pressed layer.
9. The soft-pack outer shell as described in any one of claims 1-6, characterized in that, The width of the edge sealing structure is not less than 0.2 mm and not more than 1 mm.
10. A battery, characterized in that, The device includes a battery cell and a soft-pack housing as described in any one of claims 1 to 9. The battery cell has at least two tabs with opposite polarities. The first end and the second end of the soft-pack housing are folded together to wrap around the battery cell. The first end and the second end of the soft-pack housing together wrap around at least one portion of the tab and are respectively sealed to the tab.