Novel aluminum-plastic film packaged battery
By introducing pre-folded edges and side creases into the aluminum-plastic film packaging bag, combined with tooling folding process, the problem of aluminum-plastic film folding springback was solved, thereby improving battery thickness and energy density, and enhancing molding efficiency and precision.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-28
- Publication Date
- 2026-04-07
AI Technical Summary
In traditional pouch cell battery packaging structures, the aluminum-plastic film is prone to springback when folded, resulting in low forming efficiency and low precision. Furthermore, the depth of the perforation in the aluminum-plastic film limits the battery thickness, reducing space utilization and energy density.
The aluminum-plastic film packaging bag with a pre-folded edge design forms a square tube shell by setting pre-folded edges and side marks in the packaging bag and combining it with tooling folding process, which avoids the aluminum-plastic film from springing back, and the sealing edge is fixed by heat pressing, so as to achieve a fast and accurate sealing process.
It improves battery molding efficiency and precision, increases battery thickness, enhances space utilization and module energy density, reduces the risk of aluminum-plastic film breakage, and avoids the limitations of aluminum-plastic film thickness.
Smart Images
Figure CN224096794U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of battery technology, and more specifically, to a novel aluminum-plastic film-encapsulated battery. Background Technology
[0002] Most existing traditional pouch batteries use triple or quadruple sealing structures. Taking quadruple sealing as an example: Indentations are formed by punching indentations into an aluminum-plastic film to create recesses that match the size of the bare cell. Then, two pieces of aluminum-plastic film with these recesses cover the bare cell from both sides. Finally, the four edges are sealed by heat pressing to complete the encapsulation (e.g., Figure 9 (As shown). The triple seal is achieved by symmetrically punching two indentations into a large-sized aluminum-plastic film, placing the bare battery cell into the indentation, folding the aluminum-plastic film along the center line, wrapping the bare battery cell with the two indentations, and then heat-pressing the three open edges to form a seal.
[0003] Traditional pouch cell packaging structures have the following drawbacks and shortcomings: 1. The aluminum-plastic film requires perforation, and the maximum thickness that can be produced is limited by the perforation depth of the aluminum-plastic film. The perforation depth of a single aluminum-plastic film is limited; if the perforation is too deep, it will cause the aluminum-plastic film to crack. Currently, the perforation depth available on the market is 6mm-8mm, which limits the thickness of the pouch cell, reduces space utilization, and prevents an increase in energy density. 2. In traditional pouch cell packaging processes, the aluminum-plastic film needs to be folded along a specific path. Existing aluminum-plastic films lack guiding structures, resulting in a highly arbitrary folding path. Furthermore, the aluminum-plastic film has a certain thickness, making it prone to springback, affecting molding efficiency and molding contour accuracy. Utility Model Content
[0004] The technical problem to be solved by this utility model is that in the traditional soft-pack battery cell packaging process, the aluminum-plastic film is prone to springback when folded. In view of the problems existing in the prior art, a new type of aluminum-plastic film packaged battery is provided.
[0005] The purpose and effects of this utility model are achieved by the following specific technical means:
[0006] A novel aluminum-plastic film-encapsulated battery, comprising:
[0007] A packaging bag is wrapped around the outside of the bare battery cell, and the packaging bag has at least one pre-folded edge;
[0008] The bare battery cell has two tabs at its outer end, and tab adhesive is provided at the middle of the tabs. The packaging bag is sealed and folded to encapsulate the bare battery cell, with the tabs protruding from the packaging bag.
[0009] This design allows for the direct packaging of bare battery cells by pre-forming the packaging bag into a square tubular shell, enabling rapid sealing.
[0010] A further preferred embodiment: the pre-folded edge is provided at each fold position of the bare battery cell encapsulated in the packaging bag.
[0011] A further preferred embodiment: the pre-folded edge consists of a pre-fold and side marks, and side marks are provided at 0.1mm-6mm on both sides of each pre-fold. The side marks are intermittent marks, and the spacing between the marks is ≤0.3mm.
[0012] A further preferred embodiment: The packaging bag is made of a sheet of aluminum-plastic film folded into a square tube-shaped shell. Both the upper and lower ends of the shell are provided with sealing edges. The sealing edges are sealed by folding, and the square tube-shaped shell is sealed. The sealing edge at the top is fixed with the tab adhesive.
[0013] The design allows for sufficient folding length at the sealing edge to ensure a tight seal.
[0014] A further preferred embodiment: the sheet-like aluminum-plastic film is shaped into a rectangle by wrapping around it, and the two ends are fixed by hot pressing to form a composite seam, forming a square tube-shaped shell with openings at the top and bottom.
[0015] A further preferred embodiment: the height of the sealing portion in the Y-axis direction is greater than or equal to the thickness of the square tubular shell in the Z-axis direction.
[0016] A further preferred embodiment: the bare battery cell enters the square tubular housing from top to bottom or from bottom to top, and supports are provided on both sides of the bare battery cell;
[0017] This design allows the support structure to maintain the shape of the square tubular housing during the process of the bare battery cell entering the housing, thus preventing deformation.
[0018] A further preferred embodiment: the outer end of the sealing portion is closed and then hot-pressed to form a sealed sealing section, the width of which is at least 2mm.
[0019] A further preferred embodiment: the edge sealing section is folded into the edge sealing part, and both ends of the edge sealing part are folded tightly against the outer surface of the square tubular shell;
[0020] During the sealing process, the tab adhesive is wrapped around the outer end of the edge sealing section, and the edge sealing section and the tab adhesive are fixed by heat pressing.
[0021] A further preferred embodiment: the packaging bag is composed of a PET layer, a nylon layer, an aluminum foil layer, and a PP layer, with side marks set on the surface of the PET layer.
[0022] The beneficial effects of this utility model are:
[0023] 1. This soft-pack battery has no denting process throughout the entire process, reducing the risk of aluminum-plastic film breakage. Furthermore, the thickness of the battery is not limited by the denting depth of the aluminum-plastic film. By simply increasing the size of the square tubular shell and the bare cell, the battery size can be increased. Compared to traditional soft-pack batteries, it can be made thicker. The larger battery size allows for a reduction in the number of cells during later module assembly, resulting in higher module assembly space utilization and effectively improving cell capacity and module energy density.
[0024] 2. Pre-folded edges are set at each fold position of the bare battery cell in the packaging bag. The pre-folded part is folded using a tooling. The pre-folded part is folded in the initial state. Side marks are set at 0.1mm-6mm on both sides of each pre-folded part. The side marks are intermittent marks with a spacing of ≤0.3mm between the marks. The marks do not penetrate the aluminum-plastic film. The side marks are to better bend the R-angle of the pre-folded part and avoid the thick aluminum-plastic film from springing back when folded. Attached Figure Description
[0025] The present invention will be further described below with reference to the accompanying drawings.
[0026] Figure 1 This is a schematic diagram showing the overall structure of this utility model broken down.
[0027] Figure 2 This is a schematic diagram of the installation of the packaging bag and bare battery cell structure of this utility model (top sealing section sealing).
[0028] Figure 3 This is a schematic diagram of the installation of the packaging bag and bare battery cell structure of this utility model (the top sealing section is folded).
[0029] Figure 4 This is a schematic diagram of the installation of the packaging bag and bare battery cell structure of this utility model (bottom sealing section sealing).
[0030] Figure 5 This is a schematic diagram of the installation of the packaging bag and bare battery cell structure of this utility model (the bottom sealing section is folded).
[0031] Figure 6 This is a schematic diagram of the installation of the packaging bag and bare cell structure of this utility model (with the tabs lying flat).
[0032] Figure 7 This is a schematic diagram of the bare battery cell and support structure of this utility model.
[0033] Figure 8 This is a perspective view of the soft-pack battery structure of this utility model;
[0034] Figure 9 This is a schematic diagram of the packaging structure of a traditional pouch battery.
[0035] Figure 10This is a schematic diagram of the packaging bag structure of this utility model (the dotted line part is the pre-folded part);
[0036] Figure 11 This is a diagram of the composite layered structure of the packaging bag of this utility model;
[0037] Figure 12 This is a schematic diagram of the planar structure of the packaging bag of this utility model (position of the pre-folded part);
[0038] Figures 1-12 In the middle: packaging bag (1), composite seam (101), sealing part (2), sealing section (201), bare battery cell (3), tab (301), tab adhesive (302), bracket (4), pre-folded part (5), side mark (501), PET layer (6), nylon layer (7), aluminum foil layer (8), PP layer (9). Detailed Implementation
[0039] To better understand the above-mentioned objectives, features, and advantages of this utility model, the present utility model will be further described in detail below with reference to the accompanying drawings and specific embodiments. The following embodiments are merely examples for implementing this utility model. It must be pointed out that the disclosed embodiments do not limit the scope of this utility model. On the contrary, any modifications and refinements made without departing from the scope of this utility model are within the patent protection scope of this utility model.
[0040] Please refer to the figure. Figure 11 and Figure 12 A novel aluminum-plastic film-encapsulated battery, comprising:
[0041] The packaging bag 1, in its initial state, is a sheet-like aluminum-plastic film structure. The packaging bag 1 has at least one pre-folded edge, which is located at each fold position of the bare battery cell 3 encapsulated in the packaging bag 1. For example, if the packaging bag 1 uses a three-sided sealing method to encapsulate the bare battery cell 3, then at least one pre-folded edge needs to be provided in the middle of the packaging bag 1 to facilitate the subsequent folding process. The pre-folded edge consists of a pre-folded portion 5 and a side crease 501 (e.g., ...). Figure 12 As shown), the pre-folded part 5 is folded using a tooling. The pre-folded part 5 is folded in the initial state, and side marks 501 are provided at 0.1mm-6mm on both sides of each pre-folded part 5. The side marks 501 are intermittent marks, and the spacing between the marks 501 is ≤0.3mm. The marks 501 do not penetrate the aluminum-plastic film. The side marks 501 are to better bend the R-angles on both sides of the pre-folded part 5 and avoid the aluminum-plastic film from springing back when folded due to its thickness.
[0042] The packaging bag 1 is composed of a PET layer 6, a nylon layer 7, an aluminum foil layer 8, and a PP layer 9. The composite aluminum-plastic film has good toughness and wear resistance, which can protect the bare battery cell 3. The side marks 501 are set on the surface of the PET layer, which is not easy to scratch and avoids damage to the aluminum-plastic film.
[0043] Please see Figures 1-8 and Figure 10 Foldable packaging technology:
[0044] The sheet aluminum-plastic film is formed into a square tube shell using a tooling folding process. The sheet aluminum-plastic film is then wrapped and shaped into a rectangle. To facilitate subsequent packaging and folding, pre-folded edges can be machined into the aluminum-plastic film (see reference). Figure 10 (The dotted part in the middle) The processing method can be to use tooling to compress and fold the sheet aluminum-plastic film, and overlap its first and last ends when wrapping it. The overlap width is preferably ≥2mm. The first and last ends are fixed by hot pressing the overlap position to form a composite seam 101, thus forming a square tube shell with openings at the top and bottom.
[0045] The bare cell 3 has two tabs 301 on its outer end, and the tabs 301 have adhesive in the middle. The adhesive is an insulating part on the tabs 301. Its function is to prevent short circuit between the tabs 301 and the aluminum-plastic film during the later battery encapsulation.
[0046] The bare battery cell 3 is placed into the square tubular housing from top to bottom or bottom to top. To maintain the shape of the square tubular housing and to prevent the bare battery cell 3 from being scratched by the edges of the square tubular housing, technicians can install brackets 4 on both sides of the bare battery cell 3. The brackets 4 are concave in shape and support the bare battery cell 3 on both sides. Then, the bare battery cell 3 is placed into the square tubular housing and adjusted to the middle position of the square tubular housing so that the upper and lower ends of the housing are reserved with sealing edge portions 2. The height of the reserved sealing edge portion 2 in the Y-axis direction should be greater than or equal to the thickness of the square tubular housing in the Z-axis direction. The outer end of the sealing edge portion 2 is closed and heat-pressed to form a sealed sealing edge section 201 (e.g., Figure 2 and Figure 4 The width of the sealing section 201 should be at least 2mm to ensure a tight seal and prevent air leakage later. Then, fold the sealing section 201 tightly against the shell. After folding, triangular corners will appear at both ends. Fold these triangular corners tightly against the left and right outer surfaces of the square tubular shell (e.g., Figure 5 (As shown), to prevent the corners from lifting up, you can use tape to cover the corners;
[0047] The pre-folded edges processed in the aluminum-plastic film before encapsulation and folding include triangular folds and folds at the outer end of the sealing edge 2. When completing the above folding, the technicians can guide the folding through the pre-folded edges, thereby quickly folding and forming along a specific path, improving forming efficiency and accuracy.
[0048] Furthermore, during the sealing and closing process, the top sealing section 2 should be wrapped with adhesive tape 301. During hot pressing, the sealing section 201 and the adhesive tape 301 should be correspondingly hot-pressed and fixed (e.g., Figure 2As shown), the two are thermoplastically integrated to ensure sealing. When folding the sealing section 201, the tab 301 is folded together. The tab 301 is in a flat position (as shown). Figure 6 As shown), those skilled in the art may also leave the tab 301 upright, only folding the triangular corners at both ends of the sealing portion 2, keeping the tab 301 upright (as shown). Figure 3 As shown), the tab 301 can be designed to lie flat or stand upright according to the structure of the later battery module electrical connection;
[0049] The sealing part 2 is sealed and folded, and the upper and lower ends of the square tubular shell are sealed to form a soft-pack battery (such as...). Figure 8 As shown, this soft-pack battery has no denting process throughout the entire process, reducing the risk of aluminum-plastic film breakage. Furthermore, the thickness of the battery is not limited by the denting depth of the aluminum-plastic film. By simply increasing the size of the square tubular shell and the bare cell, the battery size can be increased. Compared to traditional soft-pack batteries, it can be made thicker. The larger battery size allows for a reduction in the number of cells during later module assembly, resulting in higher module assembly space utilization and effectively improving cell capacity and module energy density.
Claims
1. A novel aluminum-plastic film-encapsulated battery, characterized in that, include: A packaging bag is wrapped around the outside of the bare battery cell, and the packaging bag has at least one pre-folded edge; The bare battery cell has two tabs on its outer end, and tab adhesive is provided in the middle of the tabs. The packaging bag is sealed and folded to encapsulate the bare battery cell, and the tabs are exposed outside the packaging bag.
2. The novel aluminum-plastic film-encapsulated battery according to claim 1, characterized in that: The pre-folded edges are provided at each fold position of the bare battery cell encapsulated in the packaging bag.
3. A novel aluminum-plastic film-encapsulated battery according to claim 2, characterized in that: The pre-folded edge consists of a pre-fold and side marks, and each pre-fold has a side mark 0.1mm-6mm from both sides of its edge. The side marks are intermittent marks with a spacing of ≤0.3mm between them.
4. A novel aluminum-plastic film-encapsulated battery according to claim 1, characterized in that: The packaging bag is made of sheet aluminum-plastic film folded into a square tube shell. Both the top and bottom ends of the shell are provided with sealing edges. The sealing edges are sealed and folded to complete the sealing of the square tube shell. The sealing edge at the top is fixed with the tab adhesive.
5. A novel aluminum-plastic film-encapsulated battery according to claim 4, characterized in that: The sheet-like aluminum-plastic film is shaped into a rectangle by wrapping around it, and the two ends are fixed by hot pressing to form a composite seam, forming a square tube shell with openings at the top and bottom.
6. A novel aluminum-plastic film-encapsulated battery according to claim 4, characterized in that: The height of the sealing portion in the Y-axis direction is greater than or equal to the thickness of the square tubular shell in the Z-axis direction.
7. A novel aluminum-plastic film-encapsulated battery according to claim 1, characterized in that: The bare battery cell enters the square tubular housing from top to bottom or from bottom to top, and supports are provided on both sides of the bare battery cell.
8. A novel aluminum-plastic film-encapsulated battery according to claim 4, characterized in that: The outer end of the sealing section is closed and then hot-pressed to form a sealed sealing section, the width of which is at least 2mm.
9. A novel aluminum-plastic film-encapsulated battery according to claim 8, characterized in that: The edge sealing section is folded into the edge sealing part, and both ends of the edge sealing part are folded tightly against the outer surface of the square tubular shell. During the sealing process, the tab adhesive is wrapped around the outer end of the edge sealing section, and the edge sealing section and the tab adhesive are fixed by heat pressing.
10. A novel aluminum-plastic film-encapsulated battery according to claim 3, characterized in that: The packaging bag is composed of a PET layer, a nylon layer, an aluminum foil layer, and a PP layer, with side marks set on the surface of the PET layer.