Novel side edge folding structure lithium ion battery cell

Abstract

The utility model belongs to the technical field of lithium ion battery manufacturing, and particularly relates to a novel lithium ion battery cell with a side edge folding structure, which comprises an aluminum-plastic shell, two pits are punched on the surface of the aluminum-plastic shell, battery cells are arranged in the pits, the aluminum-plastic shell is folded along two folding lines on the side edge, and the bottom, the top and the other side of the aluminum-plastic shell are subjected to edge sealing. For a large soft package same-side tab cell, a side edge folding structure is adopted, and finally a complete side edge is reserved, namely, a side edge plane with a complete material is formed in an area between two punching pit edges formed by punching pits and folding lines, so that the integrity of the material is ensured.

Description

Technical Field

[0001] The utility model belongs to the technical field of lithium ion battery manufacturing, and in particular relates to a novel lithium ion battery cell with a side folding structure. Background Art

[0002] In recent years, with the gradual refinement of the classification of the new energy battery market, the requirements for the rate of large soft-pack batteries have become higher and higher. At the same time, as the rate increases, the heat generated by the batteries also increases sharply, which indirectly causes heat dissipation problems. The battery cell is the most important part of the entire battery module, and its structure directly affects the assembly and performance of the module. Therefore, adding consideration of heat dissipation issues at the battery cell level is very beneficial to the heat dissipation of the entire module.

[0003] The main structure of the current battery cell is a bottom folded structure: the punching process punches holes on the two shells, then folds along the bottom edge, and then the three sides are sealed in two processes, packaging process (top sealing + side sealing) → final sealing (side sealing). The packaging process of this structure is simple to operate, requires two steps of packaging process, and the process route is mature. The bottom edge of the battery cell is finally retained as a complete aluminum plastic, and the two sides are completed by packaging; therefore, the packaging effect of the side is worse than that of the bottom edge, which also makes the bottom edge more suitable for heat dissipation glue as a heat dissipation edge.

[0004] However, for the battery cell, the heat generated at the ear is relatively large, and the heat accumulated at the head of the battery cell is relatively large. The bottom, as the heat dissipation edge, is far away from the head where there is more heat, and its heat dissipation effect is often affected. The common high-rate large soft-pack battery cell generally has an aspect ratio > 1, and uses the bottom folding position for heat dissipation. On the one hand, due to the small bottom edge, the heat dissipation effect is relatively poor. On the other hand, the battery cell is long and far away from the area with more heat at the head, which also leads to poor heat dissipation effect. Utility Model Content

[0005] The utility model aims to provide a novel lithium-ion battery cell with a side-folding structure to solve the problems existing in the background technology.

[0006] To achieve the above-mentioned purpose, the utility model provides the following technical solution: a novel lithium-ion battery cell with a side-folding structure, comprising an aluminum-plastic shell, two pits punched on the surface of the aluminum-plastic shell, the battery cell is loaded in the pits, the aluminum-plastic shell is folded along two folding lines on the side, and the bottom, top and other side of the aluminum-plastic shell are sealed.

[0007] Preferably, the distance between two folding lines is >0.5 mm.

[0008] Preferably, the depth of the recess is reduced by increasing the distance between two folding lines.

[0009] Preferably, the folded side is coated with heat dissipation glue.

[0010] Preferably, the folded side is coated with adhesive glue.

[0011] The beneficial effects of the utility model are as follows: 1. For large soft-pack cells with tabs on the same side, a side folding structure is adopted, and finally a complete side is retained, that is, the two pit edges formed by the pits and the area between the folding lines, forming a side plane with complete material, ensuring the integrity of the material. In the process of assembling the module, heat dissipation glue is applied to the side folding edge, because it is close to the tab position, so this structure is obviously beneficial to the heat dissipation of the cell;

[0012] 2. For thick cells, the area between the folding lines can be increased and the depth of the punching pit can be reduced to achieve the packaging effect of thick cells. It is also beneficial to the heat dissipation of the cells. At the same time, this structure also has the function of assembling and fixing the modules;

[0013] 3. At the same time, compared with the battery cell design with tabs on both sides, since it only includes the size of one tab front edge (batteries with tabs on both sides include two front edges), it saves part of the battery cell space and increases the energy density. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a structural schematic diagram of the utility model;

[0015] Figure 2 It is a schematic diagram of the aluminum plastic shell punching process in the utility model;

[0016] Figure 3 It is a schematic diagram of the structure of the aluminum plastic shell of the utility model after being folded in half;

[0017] Figure 4 It is a side view of the utility model;

[0018] Figure 5 It is a bottom view of the utility model. DETAILED DESCRIPTION

[0019] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0020] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying 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. In addition, the terms "first", "second", etc. are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, features defined as "first", "second", etc. may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0021] In the description of the invention, it should be noted that, unless otherwise clearly specified and limited, the terms "install", "connect", "connect", "fixed connection" and "fixed connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal connection of two components. For ordinary technicians in this field, the specific meanings of the above terms in the invention can be understood through specific circumstances. The specific implementation methods of the utility model are described in detail below in conjunction with the accompanying drawings and preferred embodiments.

[0022] like Figure 1 As shown, a novel side-folded lithium-ion battery cell comprises an aluminum-plastic shell 1, two pits 2 are punched on the surface of the aluminum-plastic shell, and the battery cell is placed in the pits. The aluminum-plastic shell is folded along two folding lines 3 on the side, wherein the distance between the two folding lines is greater than 0.5 mm. The bottom, top and other side of the aluminum-plastic shell are sealed.

[0023] The manufacturing process is:

[0024] 1. Punching process: Punch out two pits 2 on the entire aluminum-plastic shell 1. Figure 2 Then fold along the two middle fold lines 3, as shown in Figure 3 As shown, place the pole group inside the punch shell. Usually the fold line is consistent with the edge of the punch hole. The distance between the two fold lines is > 0.5mm.

[0025] 2. The cell packaging is then completed in three steps: top sealing 4 → side sealing 5 → bottom sealing 6. The top sealing edge includes the pole ear 7, so it is required to remain straight. There are no special requirements for the side and bottom sealing edges, which can be kept straight or bent according to the state of the finished cell. The packaging structure includes three steps, and there is no significant difference between the two side / bottom sealing edges. The packaging order can be arranged according to the manufacturing situation or the design of the cell.

[0026] By folding the sides, the area between the two punched edges and the folding lines forms a complete plane, rather than being packaged and bonded together, thereby ensuring the material integrity of this area.

[0027] If the cell thickness is greater than 15mm or thicker, the depth of each pit is required to be greater than 7.5mm. Due to the limitation of the pit depth of the aluminum shell, it is difficult for a single pit to reach such a depth. Therefore, the distance between the two folding lines can be increased to reduce the pit depth and achieve the packaging effect. At this time, the folded side still maintains a flat side plane, which has a more obvious heat dissipation effect on thick cells.

[0028] like Figure 4 and Figure 5 As shown, the folded side 8 formed by folding the folding line is a complete side surface, and its heat resistance is better than the edge sealing after packaging. During the assembly of the module, the side is coated with heat dissipation glue. Since it is close to the high heat generating ear area, the heat dissipation effect is obvious. At the same time, for ultra-thick battery cells, the distance between the folding lines can be increased, the depth of the punching pit can be reduced, and the packaging of ultra-thick battery cells can be achieved. In addition, the complete plane can also be coated with adhesive glue to achieve a better fixation of the battery cell in the module.

[0029] It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the utility model, and these improvements and modifications should also be regarded as the protection scope of the utility model.

Claims

1. A novel lithium-ion battery cell with a side-folding structure, characterized in that: The invention comprises an aluminum-plastic shell, wherein two pits are punched on the surface of the aluminum-plastic shell, and the battery cells are placed in the pits. The aluminum-plastic shell is folded along two folding lines on the side, and the bottom, top and the other side of the aluminum-plastic shell are sealed.

2. The novel side-folded lithium-ion battery cell according to claim 1 is characterized in that: The distance between two folding lines is >0.5 mm.

3. The novel side-folded lithium-ion battery cell according to claim 1 is characterized in that: By increasing the distance between the two fold lines, the depth of the dimple is reduced.

4. The novel side-folded lithium-ion battery cell according to claim 1 is characterized in that: The folded sides are coated with heat dissipation glue.

5. The novel side-folded lithium-ion battery cell according to claim 1 is characterized in that: The folded sides are coated with adhesive glue.

Images