Battery box connecting structure and battery pack

Abstract

The utility model discloses a battery box connecting structure and a battery pack, the battery box connecting structure comprises a lower cover body and an upper cover body, the lower cover body is provided with a plurality of side plates, and the side plates extend upwards to form first connecting plates; the edge of the upper cover body extends upwards to form a second connecting plate, the second connecting plate is provided with a deformation section and a connecting section, and the connecting section and the first connecting plate are staggered and overlapped to form a curled edge; the deformation section is provided with a first limit position and a second limit position, and the deformation section is located in the side direction of the curled edge when the deformation section is located at the first limit position; and when the deformation section is located at the second limit position, the deformation section is located above the curled edge, and the deformation section is configured to be capable of deforming from the first limit position to the second limit position. According to the utility model, when the battery cell expands, the deformation section deforms from the first limit position to the second limit position, so that the edge of the battery cell is not excessively extruded any more, the stress of each position of the battery cell is more uniform, and the service life of the battery cell can be greatly prolonged.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, and in particular to a battery box connection structure and a battery pack. Background Technology

[0002] Currently, most batteries adopt a square structure for ease of manufacturing and installation, meaning that both the upper and lower casings are square, and the battery cells are installed between the upper and lower casings.

[0003] However, currently, the upper and lower shells are connected by welding, meaning the side plate of the lower shell is welded to the edge of the upper shell, resulting in a fixed connection between them. When the battery cell expands, the connection between the upper and lower shells cannot be stretched, and the cell can only expand vertically from the middle of the shells. This causes uneven expansion at the edges of the cell, leading to excessive compression. Based on simulation experiments, the applicant found that the stress difference between the edges and the middle of the cell is more than four times, and this significant stress difference can severely impact the cell's lifespan. Summary of the Invention

[0004] In view of the above-mentioned shortcomings of the prior art, the technical problem to be solved by this utility model is to propose a battery box connection structure and battery pack to solve the problem that the large difference in stress at different parts of the battery cell affects the service life of the battery cell in the prior art.

[0005] The technical solution adopted by this utility model to solve its technical problem is a battery box connection structure, including a lower cover and an upper cover. The lower cover has multiple side plates, and the side plates extend upward to form a first connecting plate.

[0006] A second connecting plate extends upward from the edge of the upper cover. The second connecting plate has a deformable section and a connecting section. The connecting section overlaps with the first connecting plate to form a rolled edge.

[0007] The deformable segment has a first limit position and a second limit position. In the first limit position, the deformable segment is located laterally to the rolled edge. In the second limit position, the deformable segment is located above the rolled edge. The deformable segment is configured to deform from the first limit position to the second limit position.

[0008] Furthermore, the connecting segment includes a first rolled edge segment, a second rolled edge segment, and a first bent segment, with both ends of the first bent segment connected to the first rolled edge segment and the second rolled edge segment respectively, and a first gap between the first rolled edge segment and the second rolled edge segment;

[0009] The first connecting plate includes a third rolled edge segment, a fourth rolled edge segment, and a second curved segment. The two ends of the second curved segment are respectively connected to the third rolled edge segment and the fourth rolled edge segment, and there is a second gap between the third rolled edge segment and the fourth rolled edge segment.

[0010] The second rolled edge segment extends into the second gap, and the two sides of the second rolled edge segment are respectively attached to the third rolled edge segment and the fourth rolled edge segment;

[0011] The fourth rolled edge segment extends into the first gap, and the two sides of the fourth rolled edge segment are respectively attached to the first rolled edge segment and the second rolled edge segment.

[0012] Furthermore, at the first extreme position, there is a third bending segment between the deformed segment and the connecting segment, and the third bending segment is in contact with the second bending segment.

[0013] Furthermore, the end of the second rolled edge segment furthest from the first rolled edge segment abuts against the second curved segment;

[0014] The end of the fourth roll segment that is furthest from the third roll segment abuts against the first curved segment.

[0015] Furthermore, adhesive is applied between the first roll edge segment and the fourth roll edge segment.

[0016] Furthermore, the corners of the upper cover and the lower cover are welded and fixed together.

[0017] Furthermore, a battery pack is also disclosed, including the aforementioned battery box connection structure.

[0018] Furthermore, a battery cell is provided between the upper cover and the lower cover, and the expansion of the battery cell can cause the deformation segment to deform from the first limit position to the second limit position.

[0019] Compared with the prior art, the present invention has at least the following beneficial effects:

[0020] The addition of a rolled edge replaces the original welded fixing, freeing the connection between the upper and lower covers from a fixed constraint. Instead, a deformable section is formed on the second connecting plate. When the battery cell expands, the deformable section deforms from the first limit position to the second limit position, while the upper cover moves upward as a whole. This prevents excessive compression at the edges of the battery cell, resulting in more even stress distribution throughout the cell and significantly extending its lifespan. Attached Figure Description

[0021] Figure 1 This is an exploded view of the battery pack in the embodiment;

[0022] Figure 2 This is a schematic diagram of the battery pack structure in the embodiment;

[0023] Figure 3 This is a cross-sectional view of the curled edge of the deformed segment at the first extreme position in the embodiment;

[0024] Figure 4 This is a cross-sectional view of the curled edge of the deformed segment at the second extreme position in the embodiment;

[0025] In the picture:

[0026] 100. Top cover; 110. Deformation section; 120. First rolled edge section; 130. Second rolled edge section; 140. First bending section; 150. Third bending section;

[0027] 200. Lower cover; 210. Third rolled edge section; 220. Fourth rolled edge section; 230. Second bent section; 300. Battery cell. Detailed Implementation

[0028] The following are specific embodiments of the present invention, which are described in conjunction with the accompanying drawings. However, the present invention is not limited to these embodiments.

[0029] Please refer to Figures 1-4 This utility model discloses a battery box connection structure, including a lower cover 200 and an upper cover 100. The lower cover 200 has multiple side plates, and the side plates extend upward to form a first connecting plate.

[0030] The upper cover 100 extends upward from the edge of a second connecting plate, the second connecting plate having a deformable section 110 and a connecting section, the connecting section overlapping the first connecting plate to form a rolled edge;

[0031] The deformable segment 110 has a first limit position and a second limit position. In the first limit position, the deformable segment 110 is located laterally to the rolled edge. In the second limit position, the deformable segment 110 is located above the rolled edge. The deformable segment 110 is configured to deform from the first limit position to the second limit position.

[0032] Specifically, by replacing the original welded fixing with a rolled edge, the connection between the upper cover 100 and the lower cover 200 is no longer a fixed constraint, but can form a deformable segment 110 on the second connecting plate. When the battery cell 300 expands, the deformable segment 110 deforms from the first limit position to the second limit position, while the upper cover 100 moves upward as a whole. This prevents the edges of the battery cell 300 from being excessively compressed, resulting in more even stress distribution across the battery cell 300 and significantly extending its service life.

[0033] Furthermore, the connecting segment includes a first rolled edge segment 120, a second rolled edge segment 130, and a first bent segment 140. The two ends of the first bent segment 140 are respectively connected to the first rolled edge segment 120 and the second rolled edge segment 130, and a first gap exists between the first rolled edge segment 120 and the second rolled edge segment 130.

[0034] The first connecting plate includes a third rolled edge segment 210, a fourth rolled edge segment 220, and a second bent segment 230. The two ends of the second bent segment 230 are respectively connected to the third rolled edge segment 210 and the fourth rolled edge segment 220. A second gap exists between the third rolled edge segment 210 and the fourth rolled edge segment 220.

[0035] The second rolled edge segment 130 extends into the second gap, and the two sides of the second rolled edge segment 130 are respectively attached to the third rolled edge segment 210 and the fourth rolled edge segment 220;

[0036] The fourth rolled edge segment 220 extends into the first gap, and the two sides of the fourth rolled edge segment 220 are respectively attached to the first rolled edge segment 120 and the second rolled edge segment 130.

[0037] Specifically, the deformable segment 110 bends and extends downward to form a first rolled edge segment 120, the first rolled edge segment 120 bends to form a first bent segment 140, and the first bent segment 140 extends upward to form a second rolled edge segment 130; the first connecting plate extends upward to form a third rolled edge segment 210, the third rolled edge segment 210 bends to form a second bent segment 230, and the second bent segment 230 extends downward to form a fourth rolled edge segment 220. The first rolled edge segment 120, the second rolled edge segment 130, the third rolled edge segment 210, and the fourth rolled edge segment 220 are overlapped, so that the first connecting plate and the second connecting plate can be staggered together to replace the original welding fixation.

[0038] It is worth mentioning that since the rolled edge area is not fixedly connected, when the deformation section 110 reaches the second limit position, if the cell 300 continues to expand, the rolled edge area can still have a certain deformation space to provide space for the cell 300 to continue to expand.

[0039] Furthermore, at the first extreme position, there is a third bending segment 150 between the deformed segment 110 and the connecting segment, and the third bending segment 150 is in contact with the second bending segment 230.

[0040] Specifically, when the cell 300 expands, the third bending section 150 is gradually straightened and deforms together with the deformation section 110, providing space for the cell 300 to expand.

[0041] Furthermore, the end of the second rolled edge segment 130 that is away from the first rolled edge segment 120 abuts against the second curved segment 230;

[0042] The end of the fourth rolled edge segment 220 that is away from the third rolled edge segment 210 abuts against the first curved segment 140.

[0043] Specifically, one end of the second rolled edge segment 130 extends into the second gap and abuts against the inner wall of the second curved segment 230, that is, the second rolled edge segment 130 can fill the second gap, so that the contact area between the second rolled edge segment 130 and the third rolled edge segment 210 / fourth rolled edge segment 220 reaches the maximum, so as to improve the bonding strength between the first connecting plate and the second connecting plate.

[0044] Similarly, one end of the fourth roll edge segment 220 extends into the first gap and abuts against the inner wall of the first curved segment 140, that is, the fourth roll edge segment 220 can fill the first gap, so that the contact area between the fourth roll edge segment 220 and the first roll edge segment 120 / second roll edge segment 130 reaches the maximum, so as to improve the bonding strength between the first connecting plate and the second connecting plate.

[0045] Furthermore, adhesive is applied between the first rolled edge segment 120 and the fourth rolled edge segment 220.

[0046] It should be noted that the first edge section 120 and the fourth edge section 220 are located on the outermost layer of the entire edge rolling process. Applying glue to the outermost layer of the edge rolling facilitates the addition of glue during the final edge rolling process. Applying no glue to other areas allows for some deformation space, enabling the cell 300 to continue expanding after the deformation section 110 reaches its second limit position.

[0047] Furthermore, the corner of the upper cover 100 is welded and fixed to the corner of the lower cover 200.

[0048] Spot welding at the corner of the upper cover 100 and the lower cover 200 can improve the connection strength between the upper cover 100 and the lower cover 200 without affecting the expansion of the battery cell 300.

[0049] Furthermore, a battery pack is also disclosed, including the aforementioned battery box connection structure.

[0050] Furthermore, a battery cell 300 is provided between the upper cover 100 and the lower cover 200. The expansion of the battery cell 300 can drive the deformation segment 110 to deform from the first extreme position to the second extreme position.

[0051] It should be noted that all directional indicators (such as up, down, left, right, front, back, etc.) in this utility model embodiment are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicator will also change accordingly.

[0052] Furthermore, in this utility model, the use of terms such as "first," "second," and "a" is for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this utility model, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0053] In this utility model, unless otherwise explicitly specified and limited, the terms "connection," "fixing," etc., should be interpreted broadly. For example, "fixing" can mean a fixed connection, a detachable connection, or an integral part; it can mean a mechanical connection or an electrical connection; it can mean a direct connection or an indirect connection through an intermediate medium; it can mean the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0054] Furthermore, the technical solutions of the various embodiments of this utility model can be combined with each other, but only if they are based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed by this utility model.

Claims

1. A battery box connection structure, comprising a lower cover and an upper cover, characterized in that: The lower cover has multiple side plates, and the side plates extend upward to form a first connecting plate; A second connecting plate extends upward from the edge of the upper cover. The second connecting plate has a deformable section and a connecting section. The connecting section overlaps with the first connecting plate to form a rolled edge. The deformable segment has a first limit position and a second limit position. In the first limit position, the deformable segment is located laterally to the rolled edge; in the second limit position, the deformable segment is located above the rolled edge. The deformable segment is configured to deform from the first limit position to the second limit position. The connecting segment includes a first rolled edge segment, a second rolled edge segment, and a first curved segment. The two ends of the first curved segment are respectively connected to the first rolled edge segment and the second rolled edge segment, and there is a first gap between the first rolled edge segment and the second rolled edge segment. The first connecting plate includes a third rolled edge segment, a fourth rolled edge segment, and a second curved segment. The two ends of the second curved segment are respectively connected to the third rolled edge segment and the fourth rolled edge segment, and there is a second gap between the third rolled edge segment and the fourth rolled edge segment. The second rolled edge segment extends into the second gap, and the two sides of the second rolled edge segment are respectively attached to the third rolled edge segment and the fourth rolled edge segment; The fourth rolled edge segment extends into the first gap, and the two sides of the fourth rolled edge segment are respectively attached to the first rolled edge segment and the second rolled edge segment; Adhesive is applied between the first roll edge segment and the fourth roll edge segment.

2. The battery box connection structure according to claim 1, characterized in that, At the first extreme position, there is a third bending segment between the deformed segment and the connecting segment, and the third bending segment is in contact with the second bending segment.

3. The battery box connection structure according to claim 1, characterized in that, The end of the second rolled edge segment furthest from the first rolled edge segment abuts against the second curved segment; The end of the fourth roll segment that is furthest from the third roll segment abuts against the first curved segment.

4. The battery box connection structure according to claim 1, characterized in that, The corners of the upper cover and the lower cover are welded and fixed together.

5. A battery pack, characterized in that, Includes the battery box connection structure as described in any one of claims 1-4.

6. A battery pack according to claim 5, characterized in that, A battery cell is also provided between the upper cover and the lower cover. The expansion of the battery cell can cause the deformation segment to deform from the first limit position to the second limit position.

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