Battery cell packaging structure and battery cell

Abstract

The utility model belongs to the technical field of battery cell packaging, and particularly relates to a battery cell packaging structure and a battery cell. The battery cell packaging structure provided by the utility model is used for protecting the welding spots of the battery cell in the battery cell for connecting the shell and the cover body by welding, and is particularly suitable for a shell inversion scheme that the welding part is positioned at the bottom of the shell in a working state. The part, close to the outer side face of the shell, of the cover body abutting part of the battery cell packaging structure is a protection part used for welding, close to or abutting against the shell and used for forming an area where an electrolyte is difficult to flow between the sealing cover and the shell, and the reaction rate of corrosion of the electrolyte to a welding seam at the area is reduced; the cover body abutting part and the part, abutting against the shell, of the protection part can jointly form a long abutting area on the inner side of the sealing cover and the inner side of the shell, so that the contact between electrolyte and welding seams is reduced as much as possible, and the effect of protecting the welding seams is achieved. Therefore, according to the battery cell packaging structure, the welding seam failure risk can be reduced, and the safety performance of the battery cell is improved.

Description

Technical Field

[0001] The utility model belongs to the technical field of battery core packaging, and in particular relates to a battery core packaging structure and a battery core. Background Art

[0002] The existing battery cell packaging structure has a solution of sealing by welding, but the welds are easily corroded due to long-term contact with the electrolyte, which may lead to weld failure and battery cell leakage, posing a safety risk.

[0003] For example, an inverted housing design exists, where the top cover housing the terminals is integrated with the cell housing and shares the same height. This design saves internal cell space and increases energy density, but the cell seal is located on the opposite side of the top cover and requires welding.

[0004] Therefore, how to prevent the battery core weld from contacting the electrolyte, reduce the risk of weld failure, and improve the safety performance of the battery core is a technical problem that needs to be solved urgently in this field. Utility Model Content

[0005] In view of the existing phenomenon, the present invention provides a battery cell packaging structure and a battery cell, which at least solves one of the above technical problems.

[0006] The first technical solution provided in the present application is a battery cell packaging structure, comprising a shell with an open end and a sealing cover for closing the end of the shell; the sealing cover comprises a cover body and a cover abutting portion that abuts the shell for welding, and the sealing cover also includes a protective portion that is close to or abuts the inner side surface of the shell and extends toward the interior of the shell along the length direction of the shell.

[0007] Furthermore, the height of the protection portion protruding toward the inside of the shell is 2-20 mm.

[0008] Furthermore, the top of the protection portion is a plane.

[0009] Furthermore, the side of the protection part close to the shell includes: a protection section close to or abutting the shell and close to the cover abutting part, and an installation section close to the shell, located on the side of the protection section away from the cover abutting part, which is convenient for installing the sealing cover.

[0010] Furthermore, a limiting portion for limiting the position of the sealing cover is provided on the inner side of the shell.

[0011] Furthermore, the shell is in a rectangular shape, and the limiting portion is only provided on the short side of the shell.

[0012] Furthermore, the sealing cover is provided with a sealing groove, and a sealing ring for sealing the sealing cover and the housing is provided in the sealing groove.

[0013] Furthermore, the cover abutting portion further includes a welding step abutting against the end surface of the shell.

[0014] The second technical solution provided in the present application is a battery cell, comprising the above-mentioned battery cell packaging structure and an electrolyte contained inside the shell.

[0015] Furthermore, it includes a winding core immersed in the electrolyte, a protective portion is arranged between the shell and the winding core, and a slope is provided on the side of the protective portion away from the shell, and the bottom of the slope is used to limit the winding core.

[0016] The beneficial effects of this application are:

[0017] The battery cell packaging structure provided by the present application is used to protect the welding points of the battery cells in the battery cells that use welding to connect the shell and the cover, and is particularly suitable for the shell inversion scheme in which the welding point is located at the bottom of the shell under working conditions. The part of the cover abutting portion of the battery cell packaging structure close to the outer side of the shell is used for welding, and the protective portion close to or abutting the shell is used to form an area between the sealing cover and the shell where the electrolyte is difficult to flow, thereby reducing the reaction rate of the electrolyte corroding the weld there; the cover abutting portion and the part of the protective portion abutting the shell can jointly form a longer abutting area between the sealing cover and the inner side of the shell, so that the electrolyte minimizes contact with the weld to protect the weld. Therefore, the battery cell packaging structure of the present application can reduce the risk of weld failure and improve the safety performance of the battery cell. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The accompanying drawings, which are incorporated into and constitute a part of the specification, illustrate embodiments of the present invention and, together with the description, serve to explain the principles of the present invention. In these drawings, similar reference numerals are used to represent similar elements. The drawings described below are some embodiments of the present invention, but not all. Those skilled in the art can derive other drawings from these drawings without inventive effort.

[0019] Figure 1 This is a general schematic diagram of Example 1 of the present utility model;

[0020] Figure 2 It is a partial schematic diagram of the sealing cover 2;

[0021] Figure 3 for Figure 1 A schematic cross-sectional view of the connection between the long sides of the middle shell 1 and the sealing cover 2;

[0022] Figure 4 for Figure 1 A schematic cross-sectional view of the connection between the short sides of the middle shell 1 and the sealing cover 2;

[0023] Figure 5 This is a schematic diagram of the sealing cover 2 of Example 2 of the present utility model;

[0024] Figure 6This is a schematic cross-sectional view of the long side connection portion of Example 2 of the present utility model;

[0025] Figure 7 This is a schematic cross-sectional view of the short side connection of Example 2 of the present utility model;

[0026] Figure 8 This is a schematic cross-sectional view of the short side connection portion of Example 3 of the present utility model;

[0027] Reference numerals:

[0028] Cover body 200, cover body abutment portion 201, winding core 300, shell 1, limiting portion 1-1, sealing cover 2, protection portion 2-1, protection section 2-1a, installation section 2-1b, sealing groove 2-2, welding step 2-3, inclined surface 2-4, sealing ring 3. DETAILED DESCRIPTION

[0029] To make the purpose, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the embodiments described are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0030] In the description of this application, unless otherwise expressly specified or limited, the terms "connected," "connected," and "fixed" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integration; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and can refer to internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on the specific circumstances.

[0031] In this application, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may include the first and second features being in direct contact, or may include the first and second features being in contact not directly but through another feature between them. Moreover, a first feature being "above," "above," and "above" a second feature may include the first feature being directly above or obliquely above the second feature, or may simply mean that the first feature is higher in level than the second feature. A first feature being "below," "below," and "below" a second feature may include the first feature being directly below or obliquely below the second feature, or may simply mean that the first feature is lower in level than the second feature.

[0032] In the description of this embodiment, the terms "upper," "lower," "left," "right," and other orientations or positional relationships are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely for ease of description and simplified operation. They do not indicate or imply that the devices or components referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on this application. Furthermore, the terms "first" and "second" are used solely for descriptive purposes and have no special meanings.

[0033] Please refer to Figure 1-4 , Example 1 provides a battery cell packaging structure, such as Figure 1 The invention first comprises a housing 1 with an open end and a sealing cover 2 for sealing the end of the housing 1. The sealing cover 2 comprises a cover body 200 and a cover body abutting portion 201 that abuts the housing 1 for welding. The sealing cover 2 also comprises a protective portion 2-1 that abuts the inner side surface of the housing 1 and extends toward the interior of the housing 1 along the length direction of the housing 1.

[0034] In some embodiments of the present disclosure, the protection portion 2 - 1 may also be close to the housing 1 but not in contact with it.

[0035] The battery cell packaging structure provided by the present application is used to protect the welding points of the battery cells in the battery cells that use welding to connect the shell and the cover, and is particularly suitable for the shell inversion scheme where the welding point is located at the bottom of the shell in the working state. The part of the cover abutting portion 201 of the battery cell packaging structure close to the outer side of the shell is used for welding, and the protective portion 2-1 close to or abutting the shell 1 is used to form an area between the sealing cover 2 and the shell 1 where the electrolyte is difficult to flow, thereby reducing the reaction rate of the electrolyte corroding the weld there; the cover abutting portion 201 and the part of the protective portion 2-1 abutting the shell can jointly form a longer abutting area between the sealing cover and the inner side of the shell, so that the electrolyte minimizes contact with the weld to protect the weld. Therefore, the battery cell packaging structure of the present application can reduce the risk of weld failure and improve the safety performance of the battery cell.

[0036] In some embodiments of the present disclosure, the height of the protection part 2-1 protruding into the interior of the shell 1 is 2-20 mm to take into account both protection effect and ease of installation. In one embodiment, the height of the protection part 2-1 protruding into the interior of the shell 1 can be 10 mm.

[0037] Considering that setting the top of the protection part 2-1 as a pointed top will cause the tip to break easily, which may cause internal environmental pollution of the battery; and the tip may scratch the internal structure of the battery, in this embodiment, the top of the protection part 2-1 is a flat surface.

[0038] In this embodiment, the side of the protection portion 2-1 proximal to the housing 1 includes a protection segment 2-1a, which abuts the housing 1 and is proximal to the cover abutment portion 201, and a mounting segment 2-1b, which is proximal to the housing 1 and located on the side of the protection segment 2-1a distal to the cover abutment portion 201. The protection segment 2-1a abuts the housing 1 to provide a high level of protection. However, if the entire protection segment 2-1 were in abutment, it would be difficult to install the sealing cover 2 into the housing 1. Therefore, this embodiment includes a mounting segment 2-1b to facilitate installation. In this embodiment, the mounting segment 2-1b is configured as a chamfered structure that is further away from the housing than the protection segment 2-1a.

[0039] like Figure 3 In this embodiment, a stopper 1-1 is provided on the inner side of the housing 1 for abutting against the mounting section 2-1b to limit the position of the sealing cover 2. Both the mounting section 2-1b and the stopper 1-1 are easy to implement. The stopper structure formed by the chamfered structure and the stopper 1-1 facilitates the installation of the sealing cover 2 into the housing 1, ensuring installation accuracy and sealing effectiveness. The mounting section 2-1b in this embodiment is chamfered and is also used to abut against the stopper 1-1 for position limiting.

[0040] In this embodiment, the housing 1 is rectangular, and the stopper 1-1 is provided only on the short sides of the housing 1. This means that the cell packaging structure of this embodiment is implemented on the shorter sides of a prismatic battery. The applicant has discovered that placing the stopper structure formed by the chamfer and the stopper 1-1 on the short sides of the housing 1 is sufficient to achieve good positioning and limiting effects. Furthermore, placing the stopper structure on the short sides facilitates alignment during installation and, due to its shorter length, is easier to process.

[0041] like Figure 5-7 Example 2 provides a cell packaging structure substantially identical to Example 1, differing only in that, in Example 2, sealing cover 2 is provided with a sealing groove 2-2, within which is located a sealing ring 3 for sealing sealing cover 2 and housing 1. The provision of sealing groove 2-2 and sealing ring 3 further enhances the seal between sealing cover 2 and housing 1, completely preventing electrolyte from contacting the weld, and thus improving the protective effect of the present application.

[0042] In this embodiment, the sealing groove 2-2 is arranged in the protective part 2-1 so that the sealing ring 3 can be kept away from the welding position, reducing the contact between the laser welding light leakage and the sealing ring 3 to produce welding explosion points. The protective part 2-1 of this application can provide a larger setting space for the sealing groove 2-2, which is convenient for setting a large-sized sealing ring 3 and improving the sealing effect.

[0043] like Figure 8Example 4 provides a cell packaging structure substantially identical to Example 2, differing only in that, in this embodiment, the cover abutting portion 201 further includes a welding step 2-3 that abuts the end face of the housing 1. The welding step 2-3 and the end abutting the end face of the housing 1 are used for welding. This welding method can reduce the risk of laser welding light leakage and contact with the sealing ring 3, resulting in weld hot spots, but it increases the height of the cell.

[0044] Example 4 provides a battery cell, including any one of the battery cell packaging structures of Examples 1-3 and an electrolyte contained in the housing 1, which can have all their beneficial effects.

[0045] refer to Figure 6-7 Example 4 also includes a core 300 immersed in the electrolyte. A protective portion 2-1 is disposed between the housing 1 and the core 300. A slope 2-4 is disposed on the protective portion 2-1, away from the housing 1. The bottom of the slope 2-4 serves to position the core 300. The cell packaging structure of this embodiment also serves to position the battery core 300, eliminating or reducing the need for a separate structure within the cell 300 to position the core 300. The slope 2-4 also concentrates the electrolyte at the bottom of the core 300, ensuring sufficient contact between the electrolyte and the core 300.

[0046] The contents described above can be implemented individually or in combination in various ways, and these variations are all within the scope of protection of the present invention.

[0047] It should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply the existence of any such actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article, or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or device. In the absence of further limitations, an element defined by the statement "comprising a ..." does not exclude the presence of other identical elements in the process, method, article, or device comprising the element.

[0048] The above content is a further detailed description of the present invention in conjunction with specific preferred embodiments, and the specific embodiments of the present invention are not limited to these descriptions. For those skilled in the art of the present invention, several simple deductions or substitutions can be made without departing from the concept of the present invention, and all of these should be considered to fall within the scope of protection of the present invention.

Claims

1. A battery cell packaging structure, comprising a shell (1) with an open end and a sealing cover (2) for sealing the end of the shell (1); the sealing cover (2) comprises a cover body (200) and a cover body abutting portion (201) abutting against the shell (1) for welding, characterized in that: The sealing cover (2) further comprises a protection portion (2-1) close to or in contact with the inner side surface of the shell (1) and extending toward the interior of the shell (1) along the length direction of the shell (1).

2. The battery cell packaging structure according to claim 1, characterized in that: The height of the protection portion (2-1) protruding toward the interior of the housing (1) is 2-20 mm.

3. The battery cell packaging structure according to claim 1, wherein: The top of the protection portion (2-1) is a plane.

4. The battery cell packaging structure according to claim 1, characterized in that: The side of the protection portion (2-1) close to the shell (1) comprises: a protection section (2-1a) abutting against the shell (1) and close to the cover body abutting section (201); and an installation section (2-1b) close to the shell (1) and located on a side of the protection section (2-1a) away from the cover body abutting section (201) for facilitating installation of the sealing cover (2).

5. The battery cell packaging structure according to claim 1, characterized in that: A limiting portion (1-1) for limiting the position of the sealing cover (2) is provided on the inner side of the housing (1).

6. The battery cell packaging structure according to claim 5, characterized in that: The shell (1) is in the shape of a rectangular parallelepiped, and the limiting portion (1-1) is only provided on the short side of the shell (1).

7. The battery cell packaging structure according to claim 1, characterized in that: The sealing cover (2) is provided with a sealing groove (2-2), and a sealing ring (3) for sealing the sealing cover (2) and the housing (1) is provided in the sealing groove (2-2).

8. The battery cell packaging structure according to claim 1, characterized in that: The cover body abutting portion (201) further includes a welding step (2-3) abutting against the end surface of the shell (1).

9. A battery cell, characterized in that: It comprises the battery cell packaging structure according to any one of claims 1 to 8 and an electrolyte contained in the shell (1).

10. The battery cell according to claim 9, characterized in that: The invention comprises a winding core (300) immersed in an electrolyte, wherein the protective portion (2-1) is provided between the shell (1) and the winding core (300), and a slope (2-4) is provided on the side of the protective portion (2-1) away from the shell (1), and the bottom of the slope (2-4) is used for limiting the winding core (300).

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