Battery cell with elliptical structure
By using an elliptical structure design for the cell pack and casing, the problems of low space utilization and lithium plating in square cells are solved, achieving higher space utilization and performance stability.
Patent Information
- Application Number
- CN202520256202.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-02-17
- Publication Date
- 2025-11-25
- Estimated Expiration
- 2035-02-17
AI Technical Summary
Existing square battery cells have low internal space utilization and are prone to lithium plating during performance testing, leading to performance degradation.
The design employs an elliptical structure, including an elliptical core and a shell. The elliptical top cover is welded to the shell, and combined with the arc-shaped sidewalls and insulating film, it increases space utilization and mitigates lithium desorption.
This improves the space utilization of the core pack within the casing, reduces lithium plating, and enhances the performance stability and lifespan of the battery cell.
Smart Images
Figure CN223598840U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to power battery technical field especially relates to an oval structure electric core. BACKGROUND
[0002] Lithium ion battery has many advantages, for example, high voltage, small volume, light weight, high specific capacity, no memory effect, no pollution, small self-discharge and long cycle life, which makes its application in many fields develop unprecedentedly, for example, communication field, electrical appliance field, electronic information field and power equipment field and energy storage field etc.
[0003] At present, the side of the commonly used square electric core in the market adopts rectangular R angle structure, under this structure, the internal space volume utilization rate of the electric core is low, which causes that the internal group margin of the core package is low, on the other hand, in the performance test process, the lithium precipitation phenomenon is easy to occur at this position, which leads to the serious performance attenuation of the electric core. UTILITY MODEL CONTENT
[0004] The purpose of the embodiment of the utility model is to provide an oval structure electric core, which can improve the space group margin of the core package in the shell and relieve the lithium precipitation phenomenon.
[0005] In order to achieve the above purpose, the utility model adopts the following technical scheme:
[0006] An oval structure electric core is provided, which comprises a core package, a shell and an oval top cover, the cross section of the core package and the shell is oval, the shell has a containing cavity for containing the core package, one end of the shell along the height direction is an open end communicating with the containing cavity, the core package is located in the containing cavity, and the oval top cover is welded with the open end.
[0007] As a further scheme of the oval structure electric core, the shell is integrally formed by a bottom shell, two plane side walls and two circular arc side walls.
[0008] As a further scheme of the oval structure electric core, the central angle corresponding to the circular arc side wall is 25-45 degrees.
[0009] As a further scheme of the oval structure electric core, the core package has two oppositely arranged circular arc parts, the circular arc parts are adjacent to the circular arc side walls, and the central angle corresponding to the circular arc parts is consistent with the central angle corresponding to the circular arc side walls.
[0010] As a further scheme of the oval structure electric core, the shell comprises an aluminum shell and an insulating film along the thickness direction, and the insulating film is attached to the side of the aluminum shell away from the core package.
[0011] As a further scheme of the elliptical structure battery cell, the insulating film extends to the elliptical top cover and fits the edge of the elliptical top cover.
[0012] As a further scheme of the elliptical structure battery cell, a burst valve is further included, a first through hole is arranged in the center of the elliptical top cover, the shape of the first through hole is matched with the shape of the burst valve, the burst valve is arranged in the first through hole and connected with the elliptical top cover through the back adhesive.
[0013] As a further scheme of the elliptical structure battery cell, two pole columns are further included, two second through holes corresponding to the pole columns are arranged in the elliptical top cover, the shape of the second through hole is matched with the shape of the pole column, the pole column is arranged in the corresponding second through hole and sealedly connected with the elliptical top cover, and the core package is connected with the pole column through the current collector.
[0014] As a further scheme of the elliptical structure battery cell, a sealing ring is further included, one sealing ring is arranged on each pole column, and the outer periphery of the sealing ring is sealedly connected with the corresponding second through hole.
[0015] As a further scheme of the elliptical structure battery cell, the number of the core packages is two, and the two core packages are arranged side by side in the thickness direction of the core package in the accommodating cavity.
[0016] Beneficial effects:
[0017] The utility model discloses the traditional square cell is changed into elliptical structure, i. e. the core package and the shell are all designed as elliptical structure, and the core package is located in the accommodating cavity of the shell, is welded through the elliptical top cover and the open end of the shell to realize the packaging of the core package. Compared with the existing square cell with R angle, the R angle utilization space can be effectively increased, the space group margin of the core package in the shell is improved, and the lithium precipitation phenomenon near the R angle of the traditional square cell can be alleviated. BRIEF DESCRIPTION OF DRAWINGS
[0018] The utility model will be further detailed below according to the drawings and examples.
[0019] Figure 1 It is the side view of the elliptical structure battery cell of the utility model embodiment one;
[0020] Figure 2 It is the structure schematic view of the shell of the utility model embodiment one;
[0021] Figure 3 It is the structure schematic view of the elliptical structure battery cell of the utility model embodiment one;
[0022] Figure 4The structure schematic view of the shell and the core package (the core package is not completely inserted into the shell) of the second embodiment of the utility model.
[0023] In the drawing:
[0024] 10, core package; 11, arc part; 20, shell; 201, insulating film; 21, bottom shell; 22, plane side wall; 23, arc-shaped side wall; 30, oval top cover; 40, explosion-proof valve; 50, pole. DETAILED DESCRIPTION
[0025] In order to make the technical problems solved by the utility model, the technical scheme adopted and the technical effects reached more clear, the technical scheme of the embodiments of the utility model will be further described in detail below with reference to the drawings. Obviously, the described embodiments are only part of the embodiments of the utility model, not all the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by those skilled in the art without creative labor belong to the protection scope of the utility model.
[0026] In the description of the utility model, unless explicitly defined and limited, the terms "connected", "connected", "fixed" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or it can be integrated; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the communication inside two elements or the interaction relationship between two elements. For ordinary skilled in the art, the specific meaning of the above terms in the utility model can be understood according to the specific circumstances.
[0027] In the utility model, unless explicitly defined and limited, the first feature "on" or "below" the second feature can include that the first feature and the second feature are in direct contact, or the first feature and the second feature are not in direct contact but are in contact through another feature between them. Moreover, the first feature "on", "above" and "above" the second feature includes that the first feature is directly above and obliquely above the second feature, or only indicates that the horizontal height of the first feature is higher than that of the second feature. The first feature "below", "below" and "below" the second feature includes that the first feature is directly below and obliquely below the second feature, or only indicates that the horizontal height of the first feature is less than that of the second feature.
[0028] In the description of this embodiment, the terms "upper," "lower," "left," and "right," etc., refer to the orientation or positional relationships shown in the accompanying drawings. They are used solely for ease of description and simplification of operation, and do not indicate or imply that the device or component referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. Furthermore, the terms "first," "second," etc., are merely used for distinction in description and have no special meaning.
[0029] Example 1
[0030] like Figures 1 to 3 As shown, the elliptical battery cell of this embodiment includes a core package 10, a housing 20, and an elliptical top cover 30. Both the core package 10 and the housing 20 have elliptical cross-sections. The housing 20 has a receiving cavity for accommodating the core package 10. The housing 20 extends along its height direction... Figure 3 One end (in the Z direction shown) is an open end that communicates with the receiving cavity. The core package 10 is located inside the receiving cavity, and the elliptical top cover 30 is welded to the open end.
[0031] This embodiment replaces the traditional square battery cell with an elliptical structure. Both the core pack 10 and the housing 20 are designed as elliptical structures. The core pack 10 is located within the housing cavity of the housing 20. The core pack 10 is encapsulated by welding the elliptical top cover 30 to the open end of the housing 20. Compared to existing square battery cells with rounded corners, this effectively increases the space utilized at the rounded corners, improves the space margin of the core pack 10 within the housing 20, and alleviates lithium plating near the rounded corners of traditional square battery cells.
[0032] In this embodiment, the core package 10 has a wound structure.
[0033] Furthermore, such as Figure 2 As shown, the shell 20 is integrally formed from a bottom shell 21, two planar sidewalls 22, and two arc-shaped sidewalls 23. This integrally formed structure improves the structural stability of the shell 20. The two planar sidewalls 22 are located along the thickness direction of the core package 10. Figure 3 On both sides of the core package 10 (in the X direction shown), two arc-shaped sidewalls 23 are located along its length direction (as shown in the X direction). Figure 3 On both sides of the Y direction (as shown), the X, Y, and Z directions are perpendicular to each other.
[0034] Furthermore, the central angle corresponding to the arc-shaped sidewall 23 is 25°-45°. This central angle includes, but is not limited to, 25°, 26°, 28°, 30°, 31°, 32°, 35°, 38°, 40°, 42°, 44°, and 45°, depending on the size of the designed battery cell, so as to maximize the use of space for the R-angle and effectively avoid lithium plating.
[0035] Further, the core package 10 has two oppositely arranged circular arc portions 11 adjacent to the circular arc-shaped side wall 23, and the central angles of the circular arc portions 11 are consistent with the central angle of the circular arc-shaped side wall 23. For example, the shape of the core package 10 is consistent with the shape of the shell 20, and the difference is that the size of the core package 10 is smaller than the size of the shell 20. The core package 10 is in clearance fit with the inner wall of the shell 20, so as to effectively improve the space utilization of the elliptical structure battery cell.
[0036] In the embodiment, the shell 20 includes an aluminum shell (not shown in the figure) and an insulating film 201 along the thickness direction of the shell 20, and the insulating film 201 is attached to the side of the aluminum shell away from the core package 10. By attaching the insulating film 201 to the outside of the aluminum shell, the core package 10 is insulated and isolated, and the insulating film 201 can also improve the structural strength of the aluminum shell to a certain extent.
[0037] For example, the insulating film 201 extends to the elliptical top cover 30 and is attached to the edge of the elliptical top cover 30. With this structure design, the insulating film 201 can cover the welding marks between the elliptical top cover 30 and the shell 20, and protect the welding marks, thereby improving the connection stability between the elliptical top cover 30 and the shell 20 to a certain extent.
[0038] Further, the elliptical structure battery cell of the embodiment further includes an explosion-proof valve 40, and a first through hole (not shown in the figure) is formed in the center of the elliptical top cover 30. The shape of the first through hole is matched with the shape of the explosion-proof valve 40, the explosion-proof valve 40 is arranged in the first through hole and connected with the elliptical top cover 30 by means of back adhesive.
[0039] In the embodiment, the explosion-proof valve 40 is arranged in the first through hole and connected with the elliptical top cover 30 by means of back adhesive. When the core package 10 is accidentally exploded, the explosion-proof valve 40 can be first broken, so that the generated airflow or liquid can overflow through the position of the explosion-proof valve 40.
[0040] Optionally, the back adhesive is single-sided back adhesive.
[0041] Further, the elliptical structure battery cell of the embodiment further includes two pole columns 50, and two second through holes (not shown in the figure) corresponding to the pole columns 50 are formed in the elliptical top cover 30 at intervals. The shape of the second through hole is matched with the shape of the pole column 50, the pole column 50 is arranged in the corresponding second through hole and connected with the elliptical top cover 30 in a sealed manner, and the core package 10 is connected with the pole column 50 through the current collector.
[0042] Specifically, the pole column 50 includes a positive pole column and a negative pole column, the positive pole sheet of the core package 10 is connected with the positive pole column through the positive current collector, and the negative pole sheet of the core package 10 is connected with the negative pole column through the negative current collector. The pole column 50 is connected with the corresponding second through hole in a sealed manner, so as to improve the sealing effect.
[0043] Furthermore, the elliptical battery cell in this embodiment also includes a sealing ring (not shown in the figure). Each terminal 50 is fitted with a sealing ring, and the outer circumference of the sealing ring is sealed to the corresponding second through hole. By using a sealing ring to achieve a sealed connection between the terminal 50 and the second through hole, installation is convenient and the sealing performance is good.
[0044] Example 2
[0045] like Figure 4 As shown, this embodiment is basically the same as the above embodiment, except that there are two core packages 10, and the two core packages 10 are arranged side by side in the receiving cavity along their thickness direction (X direction in the figure).
[0046] This embodiment adopts a dual-core pack structure, which can further increase the volume utilization rate of the elliptical structure battery cell.
[0047] Of course, in other embodiments, the number of core packs 10 is not limited to one or two, but depends on the actual size of the elliptical structure cell.
[0048] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and not to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application, and they should all be covered within the scope of the claims and specification of this application. In particular, as long as there is no structural conflict, the various technical features mentioned in the embodiments can be combined in any way. This application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.
Claims
1. An elliptical structural cell, characterized by, The battery includes a core package, a shell and an oval-shaped top cover, the core package and the shell are both oval-shaped in cross section, the shell has a receiving cavity for accommodating the core package, the shell has an open end at one end along its height direction, the core package is located in the receiving cavity, and the oval-shaped top cover is welded to the open end.
2. The elliptical structural cell of claim 1, wherein, The shell is integrally formed by a bottom shell, two planar side walls and two circular-arc side walls.
3. The elliptical structural cell of claim 2, wherein, The circular-arc side walls correspond to a central angle of 25°-45°.
4. The elliptical structural cell of claim 3, wherein, The core package has two oppositely arranged circular-arc portions adjacent to the circular-arc side walls, and the circular-arc portions correspond to the same central angle as the circular-arc side walls.
5. The elliptical structural cell of claim 1, wherein, The shell includes an aluminum shell and an insulating film along its thickness direction, and the insulating film is attached to a side of the aluminum shell away from the core package.
6. The elliptical structural cell of claim 5, wherein, The insulating film extends to the oval-shaped top cover and is attached to the edge of the oval-shaped top cover.
7. The elliptical structural cell of claim 1, wherein, An explosion-proof valve is further included, a first through hole is formed in the center of the oval-shaped top cover, the shape of the first through hole matches that of the explosion-proof valve, the explosion-proof valve is arranged in the first through hole and connected to the oval-shaped top cover through a back adhesive.
8. The elliptical structural cell of claim 1, wherein, Two pole columns are further included, two second through holes corresponding to the pole columns are formed in the oval-shaped top cover at intervals, the shape of the second through holes matches that of the pole columns, the pole columns are arranged in the corresponding second through holes and sealingly connected to the oval-shaped top cover, and the core package is connected to the pole columns through a current collector.
9. The elliptical structural cell of claim 8, wherein, A sealing ring is further included, one sealing ring is arranged on each pole column, and the outer periphery of the sealing ring is sealingly connected to the corresponding second through hole.
10. The elliptical structural cell of any of claims 1 to 9, wherein, The number of the core packages is two, and the two core packages are arranged side by side in the receiving cavity along their thickness direction.