Battery cell and battery pack
By designing an extension and folding structure in the cell sealing area, the problem of inconvenient folding caused by unreasonable sealing area size is solved, improving the stability of the cell and the safety performance of the battery pack.
Patent Information
- Application Number
- CN202423255927.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-27
- Publication Date
- 2026-01-23
- Estimated Expiration
- 2034-12-27
AI Technical Summary
The existing battery cell has an unreasonable design for the sealing area size, which makes folding the edges inconvenient.
Design a cell structure in which the sealing area includes an extension and a folded edge structure. The length of the extension is 0.5mm≤L≤3mm. The folded edge structure is spaced a certain distance from the side of the encapsulation body. The folded edge structure is also set in the battery pack to abut against the bottom of the box to provide a buffer and shock absorption effect.
The design of the sealing area is optimized to avoid the inconvenience of folding, improve the stability and strength of the battery cells, and enhance the safety performance and volumetric energy density of the battery pack.
Smart Images
Figure CN223828559U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of battery cell technology, specifically to a battery cell and battery pack. Background Technology
[0002] A pouch cell consists of electrode groups, a sealing film, and outer tabs. The sealing film protects the electrode groups. During the assembly of the sealing film and electrode groups, a receiving groove is first stamped into a designated position on the sealing film. The electrode group is placed inside the receiving groove, and then the outer sealing film of the electrode group is folded and heat-sealed to complete the packaging. The outer sealing film of the electrode group forms a sealing edge area. To reduce the space occupied by the sealing edge area and to prevent the cut edges of the sealing film from scratching the cell, the sealing edge area is folded to form a folded structure. The existing sealing edge area's size design is unreasonable, leading to inconvenient folding. Utility Model Content
[0003] In view of this, the present invention provides a battery cell and a battery pack to solve the problem of inconvenient edge folding caused by unreasonable size design of the sealing area of the battery cell in the prior art.
[0004] In a first aspect, this utility model provides a battery cell, comprising:
[0005] pole group;
[0006] An encapsulation film includes an encapsulation body and a sealing area. The encapsulation body covers the outside of the electrode assembly, and the sealing area is located outside the electrode assembly. The sealing area includes an extension and a folded edge structure. The folded edge structure is bent toward one side of the electrode assembly in the thickness direction, and the folded edge structure includes at least two folded edge segments. The extension extends toward the outside of the electrode assembly, and the length of the extension is L, 0.5mm≤L≤3mm.
[0007] Beneficial effects: The cell structure of this type includes an extension and a folded edge structure in the sealing area. The extension first extends a certain distance outward towards the electrode assembly and then bends to form the folded edge structure. The length of the extension meets the requirement of 0.5mm≤L≤3mm. The reasonable size design of the sealing area allows for an appropriate gap between the folded edge structure and the side of the encapsulation body, avoiding inconvenience caused by excessively small or large gaps. At the same time, the extension length is moderate. Compared with folded edge structures with excessively long extensions, the folded edge structure and the overall structure of the extension are more stable, reliable, and have higher strength after folding in the sealing area of this type of structure. The folded edge structure is set at a certain distance from the side of the encapsulation body, and it has a certain elastic deformation capability. When the cell is used in a battery pack, some cells with folded edge structures can be placed at the bottom of the battery pack housing. The folded edge structure abuts against the bottom wall of the housing, and it can play a certain role in buffering and shock absorption to protect the cell.
[0008] In one optional embodiment, the height of the folded edge structure extending along the thickness direction of the pole group is h, where 0.4 ≤ L / h ≤ 0.8.
[0009] Beneficial effects: This setting makes the ratio of the length of the extension to the height of the folded structure moderate. By controlling the two within this ratio range, the extension can change proportionally according to the height of the folded structure, which helps to improve the stability of the overall structure of the folded structure and the extension, ensures the strength of both, and helps to improve the buffering effect of the folded structure after the cells are assembled into the battery pack, thereby improving the safety performance of the battery pack.
[0010] In one optional embodiment, the thickness of the battery cell on the side where the folded edge structure is located is H, where h ≤ H.
[0011] Beneficial effects: The folded edge structure does not extend beyond the large surface of the battery cell. This design reduces the space occupied by the folded edge structure in the thickness direction of the battery cell, which is beneficial to improving the volumetric energy density of the battery cell.
[0012] In one alternative implementation, 0.4 ≤ L / H ≤ 0.8.
[0013] In one alternative implementation, the folded edge structure is tilted toward the pole group side.
[0014] Beneficial effect: This setting allows the folded edge structure to be fully bent, preventing deformation or warping of the folded edge structure.
[0015] In one optional embodiment, the included angle between the folded edge structure and the extension is α, where 60°≤α<90°.
[0016] In one alternative embodiment, a buffer structure is further included, the buffer structure being disposed between the folded edge structure and the side of the encapsulation body.
[0017] Beneficial effects: The buffer structure is supported between the folded edge structure and the side of the encapsulation body, which can improve the overall strength of the folded edge structure. With the folded edge structure of the cell facing the bottom of the battery pack box, the buffer structure can effectively improve the buffering and shock absorption effect of the folded edge structure.
[0018] In one alternative embodiment, the cushioning structure is made of at least one of silicone, polyurethane, and rubber.
[0019] Secondly, this utility model also provides a battery pack, including the battery cell and housing as described above, wherein the battery cell is disposed within the housing. The battery pack includes the battery cell and has the same technical effects as the battery cell, which will not be elaborated further here.
[0020] In one alternative embodiment, the folded edge structure on one side of the battery cell is located at the bottom of the housing.
[0021] Beneficial effects: The folded edge structure abuts against the bottom wall of the box, and the folded edge structure can play a certain role in buffering and reducing pressure to protect the battery cells and improve the safety performance of the battery pack. Attached Figure Description
[0022] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.
[0023] Figure 1 This is a side view of a battery cell according to an embodiment of the present utility model;
[0024] Figure 2 for Figure 1 Enlarged view of part A in the middle;
[0025] Figure 3 This is a schematic diagram of a battery cell according to an embodiment of the present utility model;
[0026] Figure 4 This is a top view of a battery cell according to an embodiment of the present utility model.
[0027] Explanation of reference numerals in the attached figures:
[0028] 1. Electrode assembly; 2. Encapsulation film; 21. Encapsulation body; 22. Sealing area; 221. Extension; 222. Folded edge structure; 2221. Folded edge section. Detailed Implementation
[0029] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.
[0030] The following is combined Figures 1 to 4 The following describes embodiments of the present invention.
[0031] According to an embodiment of the present invention, a battery cell is provided, comprising an electrode assembly 1 and an encapsulation film 2. The encapsulation film 2 comprises an encapsulation body 21 and an edge sealing area 22. The encapsulation body 21 covers the electrode assembly 1, and the edge sealing area 22 is located outside the electrode assembly 1. The edge sealing area 22 comprises an extension 221 and a folded edge structure 222. The folded edge structure 222 is bent toward one side of the electrode assembly 1 in the thickness direction, and the folded edge structure 222 comprises at least two folded edge segments 2221. The extension 221 extends toward the outside of the electrode assembly 1, and the length of the extension 221 is L, 0.5mm≤L≤3mm.
[0032] In this battery cell structure, the sealing area 22 includes an extension 221 and a folded edge structure 222. The extension 221 extends outward towards the electrode group 1 for a certain distance before being bent to form the folded edge structure 222. The length of the extension 221 satisfies 0.5mm≤L≤3mm. The sealing area size is reasonably designed, which allows for an appropriate gap between the folded edge structure 222 and the side of the encapsulation body 21, avoiding inconvenience caused by too small or too large a gap. At the same time, the length of the extension 221 is moderate, compared to the length of the extension 221 being excessive. The long-term folded edge structure 222 ensures that the folded edge structure 222 and the extension 221 have a stable and reliable overall structure with high strength after the sealing area 22 is folded. The folded edge structure 222 is set at a certain distance from the side of the encapsulation body 21, and it has a certain elastic deformation capability. When the battery cell is used in the battery pack, some of the battery cells with the folded edge structure 222 can be set at the bottom of the battery pack box. The folded edge structure 222 abuts against the bottom wall of the box and can play a certain role in buffering and shock absorption to protect the battery cell.
[0033] In some embodiments, such as Figure 2 As shown, the height of the folded edge structure 222 extending along the thickness direction of the electrode group 1 is h, 0.4≤L / h≤0.8. This setting makes the ratio of the length of the extension 221 to the height of the folded edge structure 222 moderate. By controlling the two within this ratio range, the extension 221 can change proportionally according to the height of the folded edge structure 222, which is beneficial to improving the stability of the overall structure of the folded edge structure 222 and the extension 221, ensuring the strength of both, and improving the buffering effect of the folded edge structure 222 after the cells are assembled into a battery pack, thereby improving the safety performance of the battery pack.
[0034] In some embodiments, such as Figure 1 and Figure 2 As shown, the thickness of the cell on the side where the folded edge structure 222 is located is H, that is, the distance from the sealing area 22 to the top or bottom surface of the cell is H, h≤H, that is, the folded edge structure 222 does not exceed the large surface of the cell. This setting can reduce the space occupied by the folded edge structure 222 in the thickness direction of the cell, which is beneficial to improving the volumetric energy density of the cell.
[0035] In some alternative embodiments, 0.4 ≤ L / H ≤ 0.8. The height of the folded edge structure 222 is approximately the same as the height of the cell on its side, and the length L of the extension 221 and the height H of the cell on the side of the folded edge structure 222 satisfy 0.4 ≤ L / H ≤ 0.8. This arrangement makes the extension 221 vary proportionally according to the thickness of the cell, which is beneficial to the stability of the overall structure of the folded edge structure 222 and the extension 221, ensuring their strength and improving the buffering effect of the folded edge structure 222 after the cells are assembled into a battery pack, thereby improving the safety performance of the battery pack.
[0036] If the folded edge structure 222 is not bent properly after bending, it is prone to deformation or warping. To avoid this problem, in some embodiments, the folded edge structure 222 is tilted towards the pole group 1, that is, the folded edge structure 222 is tilted inward towards the pole group 1, so as to fully bend the folded edge structure 222 and prevent the folded edge structure 222 from deforming or warping.
[0037] In some embodiments, the extension 221 extends outward from the electrode group 1 in a manner that is approximately parallel to the large surface of the battery cell. There is an angle between the folded edge structure 222 and the extension 221. In some embodiments, the angle between the folded edge structure 222 and the extension 221 is α, where 60°≤α<90°. This arrangement allows the folded edge structure 222 to bend sufficiently inward from the electrode group 1, effectively preventing the folded edge structure 222 from deforming or warping.
[0038] In some embodiments, such as Figure 1 and Figure 2 As shown, the sealing area 22 is located in the middle region of the electrode group 1 in the thickness direction. The encapsulation film 2 is provided with two receiving grooves. The electrode group 1 is placed in the receiving grooves. The folded edge structure 222 is bent toward the top or bottom of the cell.
[0039] In other embodiments, the sealing area 22 is located on one side in the thickness direction of the battery cell, the encapsulation film 2 is provided with a receiving groove, the electrode group 1 is disposed in the receiving groove, and the folded edge structure 222 is bent upward.
[0040] In some embodiments, the battery cell further includes a buffer structure disposed between the folded edge structure 222 and the side of the encapsulation body 21. The buffer structure is supported between the folded edge structure 222 and the side of the encapsulation body 21, which can improve the overall strength of the folded edge structure 222. With the folded edge structure 222 of the battery cell facing the bottom of the battery pack housing, the buffer structure can effectively improve the buffering and shock absorption effect of the folded edge structure 222.
[0041] In some alternative embodiments, the material of the cushioning structure includes at least one of silicone, polyurethane, and rubber. The material of the cushioning structure has a certain degree of elasticity, which can improve the cushioning and shock absorption effect of the folded edge structure 222. For example, in some embodiments, the cushioning structure is sheet-like and is adhesively fixed to the sides of the folded edge structure 222 and the encapsulation body 21.
[0042] like Figure 1 and Figure 2 As shown, in some embodiments, the folded edge structure 222 includes two folded edge segments 2221, which fit together to improve the overall strength of the folded edge structure 222 and prevent the folded edge structure 222 from warping.
[0043] In some embodiments, the folded edge segment 2221 away from the extension 221 is bent toward the inside of the electrode group 1; in other embodiments, the folded edge segment 2221 away from the extension 221 is bent outwards toward the electrode group 1. The end of the folded edge segment 2221 away from the extension 221 is the cut edge of the encapsulation film 2. The fact that the folded edge segment 2221 away from the extension 221 is positioned away from the electrode group 1 allows the cut edge to be kept away from the encapsulation body 21, thus preventing damage to the encapsulation body 21 from the cut edge.
[0044] In other embodiments, the folded edge segment 2221 of the folded edge structure 222 may be provided in three, four, or five segments, etc., and each folded edge segment 2221 may be bent inward toward the pole group 1 or bent outward away from the pole group 1 in sequence.
[0045] like Figure 3 and Figure 4 As shown, in some embodiments, the battery cell further includes an internal tab, an external tab, and tab adhesive. The external tab includes an external positive tab and an external negative tab, which are located on the same side of the electrode group 1. In this case, the battery cell has tabs on only one side, resulting in a simple battery cell structure. This simplifies the battery cell structure and manufacturing process, and improves the battery cell production efficiency.
[0046] In other embodiments, the external tabs include an external positive tab and an external negative tab, which are located on two opposite sides of the electrode group 1. In this case, the cell has tabs on both sides, and this structure can provide a more uniform current distribution, thereby improving the cell's performance and lifespan.
[0047] The internal tabs include an internal positive tab and an internal negative tab. The internal positive tab is located inside the encapsulation film 2, and one end of it is soldered to the electrode assembly 1. One end of the external positive tab is located inside the encapsulation film 2, and the other end extends out of the encapsulation film 2. The end of the external positive tab inside the encapsulation film 2 is soldered to the internal positive tab. Similarly, the internal negative tab is located inside the encapsulation film 2, and one end of it is soldered to the electrode assembly 1. One end of the external negative tab is located inside the encapsulation film 2, and the other end extends out of the encapsulation film 2. The end of the external negative tab inside the encapsulation film 2 is soldered to the internal negative tab. Tab adhesive is disposed between the external tab and the encapsulation film 2.
[0048] According to an embodiment of the present invention, another aspect provides a battery pack, including the aforementioned battery cell and housing, wherein the battery cell is disposed within the housing.
[0049] In this battery pack structure, the sealing area 22 of the cell includes an extension 221 and a folded edge structure 222. The extension 221 extends outward toward the electrode group 1 for a certain distance before being bent to form the folded edge structure 222. The length of the extension 221 satisfies 0.5mm≤L≤3mm, so that there is an appropriate gap between the folded edge structure 222 and the side of the encapsulation body 21, avoiding the inconvenience of folding when the gap is too small or too large. At the same time, the length of the extension 221 is moderate. Compared with the structure when the extension 221 is too long, the overall structure of the folded edge structure 222 and the extension 221 after folding is stable, reliable, and has high strength.
[0050] In some alternative embodiments, the folded edge structure 222 on one side of the battery cell is located at the bottom of the housing. The folded edge structure 222 abuts against the bottom wall of the housing. The folded edge structure 222 can play a certain role in buffering and reducing pressure to protect the battery cell and improve the safety performance of the battery pack.
[0051] Although embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations all fall within the scope defined by the appended claims.
Claims
1. A battery cell, characterized in that, include: pole group; An encapsulation film includes an encapsulation body and a sealing area. The encapsulation body covers the outside of the electrode assembly, and the sealing area is located outside the electrode assembly. The sealing area includes an extension and a folded edge structure. The folded edge structure is bent toward one side of the electrode assembly in the thickness direction, and the folded edge structure includes at least two folded edge segments. The extension extends toward the outside of the electrode assembly, and the length of the extension is L, 0.5mm≤L≤3mm.
2. The battery cell according to claim 1, characterized in that, The height of the folded edge structure extending along the thickness direction of the pole group is h, where 0.4 ≤ L / h ≤ 0.
8.
3. The battery cell according to claim 2, characterized in that, The thickness of the battery cell on the side where the folded edge structure is located is H, where h ≤ H.
4. The battery cell according to claim 3, characterized in that, 0.4≤L / H≤0.
8.
5. The battery cell according to any one of claims 1 to 4, characterized in that, The folded edge structure is inclined toward the pole group side.
6. The battery cell according to any one of claims 1 to 4, characterized in that, The included angle between the folded edge structure and the extension is α, where 60°≤α<90°.
7. The battery cell according to any one of claims 1 to 4, characterized in that, It also includes a buffer structure, which is disposed between the folded edge structure and the side of the encapsulation body.
8. The battery cell according to claim 7, characterized in that, The material of the cushioning structure includes at least one of silicone, polyurethane, and rubber.
9. A battery pack, characterized in that, The battery cell and housing as described in any one of claims 1 to 8 are included, wherein the battery cell is disposed within the housing.
10. The battery pack according to claim 9, characterized in that, The folded edge structure on one side of the battery cell is located at the bottom of the housing.