Battery box structure for a square battery cell

Abstract

The present invention provides a battery box structure for a square battery cell, belonging to the field of lithium-ion battery boxes. It solves the problems that the existing box body is of a split-open type, with high overall dimensional accuracy requirements for the welding of the two split battery box bodies; and electric spark damage to electrical components is likely to occur during resistance welding. A battery box structure for a square battery cell includes an upper cover, a box body, and a lower cover. One end of the box body is open, an installation cavity for the battery cell to be inserted is arranged inside the box body, a plurality of openings for exposing the lead electrodes of the battery cell are arranged at the other end of the box body, a trapezoidal partition strip is arranged between adjacent openings, the trapezoidal partition strip is located inside the box body, a protection plate is arranged between the upper cover and the box body, the box body is provided with positioning posts for installing the protection plate, and after the protection plate is installed by the positioning posts, the upper ends of the positioning posts are melted and fixed to the protection plate by ultrasonic heat melting. The present invention has the advantages of convenient assembly, compact structure, etc.

Description

Technical Field

[0001] The present invention belongs to the field of lithium-ion battery boxes, and particularly relates to a battery box structure for square battery cells. Background Art

[0002] Currently, for the installation structure of square battery cells in the market, most use structural adhesive plus end plates at both ends, and bolts are used to tighten and fix them around. Its structure is not compact, resulting in large weight, large volume, high material cost and high labor cost.

[0003] Chinese Patent CN201410082560.6 "Battery Installation Structure for Lithium Battery Module" discloses a split battery box structure. However, since its box body is split, the overall dimensional accuracy requirements for welding the two split battery box bodies are high. Otherwise, the second welding of the upper cover cannot be carried out. Moreover, the mold development, material process, etc. of the two split battery box bodies must have high precision. Otherwise, the two split battery boxes cannot be aligned, involving high costs.

[0004] And the connection between the existing protection board and the battery cell is by resistance welding. The reliability is not high, and sparks are easily generated during spot welding, which damages electrical components and affects the safety performance of the battery. The method of resistance welding is complex in manual operation and has low automation. Summary of the Invention

[0005] The purpose of the present invention is to provide a battery box structure for square battery cells aiming at the above problems existing in the prior art.

[0006] The purpose of the present invention can be achieved by the following technical solutions: A battery box structure for square battery cells, characterized in that it includes an upper cover, a box body and a lower cover. One end of the box body is open. An installation cavity for installing the battery cell is provided inside the box body. Multiple openings for exposing the lead electrodes of the battery cell are provided at the other end of the box body. A trapezoidal partition strip is provided between adjacent openings. The trapezoidal partition strip is located inside the box body. A protection board is provided between the upper cover and the box body. The box body is provided with positioning columns for installing the protection board. After the protection board is installed on the positioning columns, the upper ends of the positioning columns are melted and fixed to the protection board by ultrasonic hot melting.

[0007] Working principle of the present invention: The battery cell enters the box body from the opening of the box body. The battery cell is installed in the installation cavity. After the battery cell is installed, the lead-out electrode of the battery cell is exposed from the opening hole. Adjacent battery cells are separated by trapezoidal partition strips. And because the trapezoidal partition strips are trapezoidal, the trapezoidal partition strips also play a role in fixing the battery cells, and there is no need to set up additional fixing structures to fix the battery cells. For the traditional Chinese patent CN201410082560.6 "Battery installation structure for lithium battery module", in order to maintain the stability of the battery cells, additional structures are needed to fix the battery cells. Otherwise, during use, the battery cells are prone to small movements. The protection board is installed on the box body through positioning posts. When the positioning posts install the protection board, the upper ends of the positioning posts melt through ultrasonic hot melting, so that the positioning posts and the protection board are fixedly connected. The protection board is fixed on the box body without screws, the welding is convenient, there will be no sparks, there will be no damage to electrical components, and it will not affect the safety performance of the battery. The welding is reliable and the degree of automation is high. And the present invention adopts the assembly method of the upper cover, the box body and the lower cover, the assembly is simple, the requirement for precision is low, and the structure is compact. In the traditional Chinese patent CN201410082560.6 "Battery installation structure for lithium battery module", the left and right half box bodies need to be aligned, the requirement for precision is high, and the assembly is very inconvenient.

[0008] In the above-mentioned battery installation structure of a lithium battery module, the lower cover is provided with a plurality of partition strips for separating each battery cell, and the partition strips and the trapezoidal partition strips correspond one by one.

[0009] In the above-mentioned battery installation structure of a lithium battery module, the upper end of the positioning post forms a fixing buckle after hot melting, and the fixing buckle is buckled on the protection board.

[0010] In the above-mentioned battery installation structure of a lithium battery module, electrical connection devices are arranged on both sides of the protection board, and both ends of the electrical connection devices are electrically connected to the lead-out electrodes of adjacent battery cells respectively.

[0011] In the above-mentioned battery installation structure of a lithium battery module, the electrical connection devices are connected to the protection circuit on the protection board, and the electrical connection devices and the protection board are laser welded.

[0012] In the above-mentioned battery installation structure of a lithium battery module, the box body is further provided with a supporting part for supporting the protection board.

[0013] In the above-mentioned battery installation structure of a lithium battery module, a plurality of protruding parts are arranged on both sides of the protection board, mounting holes are arranged on the protruding parts corresponding to the positioning posts, and the remaining protruding parts are placed on the supporting part.

[0014] In the above battery installation structure of a lithium battery module, the upper cover and the box body are ultrasonically welded, and the lower cover and the box body are ultrasonically welded.

[0015] In the above battery installation structure of a lithium battery module, the long side of the trapezoidal partition strip is fixedly connected to the box body.

[0016] Compared with the prior art, the present invention has the following advantages:

[0017] 1. In the present invention, adjacent battery cells are separated by trapezoidal partition strips. Since the trapezoidal partition strips are trapezoidal in shape, the trapezoidal partition strips also play a role in fixing the battery cells, and there is no need to set up additional fixing structures to fix the battery cells.

[0018] 2. In the present invention, the protection board is installed on the box body through positioning posts. After the positioning posts install the protection board, through ultrasonic heat melting, the upper ends of the positioning posts melt, so that the positioning posts and the protection board are fixedly connected. The protection board is fixed on the box body without screws, the welding is convenient, no sparks are generated, there is no damage to electrical components, and the safety performance of the battery is not affected. The welding is reliable and the degree of automation is high.

[0019] 3. The present invention adopts an assembly method of an upper cover, a box body, and a lower cover, which is simple in assembly, has low requirements for precision, and has a compact structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 is an exploded structure schematic diagram of the present invention;

[0021] Figure 2 is a structural schematic diagram of the positioning post of the present invention;

[0022] Figure 3 is a structural schematic diagram of the box body of the present invention;

[0023] Figure 4 is a structural schematic diagram of the trapezoidal partition strip of the present invention;

[0024] Figure 5 is an enlarged structural schematic diagram of the trapezoidal partition strip of the present invention;

[0025] Figure 6 is a structural schematic diagram of the positioning post before ultrasonic heat melting of the present invention;

[0026] Figure 7 is a structural schematic diagram of the positioning post after ultrasonic heat melting of the present invention.

[0027] In the figure, 1. Upper cover; 2. Box body; 3. Lower cover; 4. Opening; 5. Installation cavity; 6. Opening hole; 7. Trapezoidal partition strip; 8. Protection board; 9. Positioning post; 10. Partition strip; 11. Fixed buckle; 12. Electrical connection device; 13. Support part; 14. Protruding part; 15. Installation hole. Detailed Implementation Modes

[0028] The following are specific embodiments of the present invention. In combination with the accompanying drawings, the technical solutions of the present invention will be further described, but the present invention is not limited to these embodiments.

[0029] As Figure 1-7 shown, a battery box structure for a square battery cell includes an upper cover 1, a box body 2, and a lower cover 3. One end of the box body 2 is open 4. An installation cavity 5 for installing the battery cell is provided inside the box body 2. A plurality of openings 6 for exposing the lead electrodes of the battery cell are provided at the other end of the box body 2. A trapezoidal partition 7 is provided between adjacent openings 6. The trapezoidal partition 7 is located inside the box body 2. A protection board 8 is provided between the upper cover 1 and the box body 2. The box body 2 is provided with positioning posts 9 for installing the protection board 8. When the protection board 8 is installed on the positioning posts 9, the upper ends of the positioning posts 9 are melted and fixed to the protection board 8 by ultrasonic heat melting.

[0030] Further elaborating, the lower cover 3 is provided with a plurality of partition strips 10 for separating each battery cell. The partition strips 10 and the trapezoidal partition strips 7 correspond one by one.

[0031] After the battery cell is installed in the box body 2, the lower cover 3 is covered. When the lower cover 3 is covered, the bottom of the battery cell is inserted between two partition strips 10. The partition strips 10 play a role in separating the battery cells. The partition strips 10 and the trapezoidal partition strips 7 correspond one by one. The partition strips 10 also play a role in limiting the position of the battery cell.

[0032] Further elaborating, a fixing buckle 11 is formed after the upper end of the positioning post 9 is heat melted. The fixing buckle 11 is buckled on the protection board 8.

[0033] After the positioning post 9 passes through the installation hole 15, the upper end of the positioning post 9 is melted by ultrasonic heat melting. After the upper end of the positioning post 9 is melted, a fixing buckle 11 is formed. The fixing buckle 11 buckles the protection board 8 on the box body 2, that is, the protection board 8 is fixed on the box body 2. There is no need for screws, the welding is convenient, there will be no sparks, it will not damage the electrical components, it will not affect the safety performance of the battery, the welding is reliable, and the automation degree is high.

[0034] Further elaborating, electrical connection devices 12 are provided on both sides of the protection board 8. The two ends of the electrical connection devices 12 are electrically connected to the lead electrodes of adjacent battery cells respectively. The two ends of the electrical connection devices 12 are used for electrically connecting to the lead electrodes of adjacent battery cells.

[0035] Further elaborating, the electrical connection devices 12 are connected to the protection circuit on the protection board 8. The electrical connection devices 12 and the protection board 8 are laser welded. Laser welding is more reliable than resistance welding, has a high automation degree, and low labor costs.

[0036] Specifically, a support portion 13 for supporting the protection plate 8 is further provided on the box body 2. A plurality of protruding portions 14 are provided on both sides of the protection plate 8. Mounting holes 15 are provided on the protruding portions 14 corresponding to the positioning posts 9, and the remaining protruding portions 14 are placed on the support portion 13.

[0037] The mounting holes 15 of the protruding portions 14 are for the positioning posts 9 to be inserted, the support portion 13 is for the remaining protruding portions 14 to be placed, both ends of the electrical connection device 12 are electrically connected to the lead-out electrodes of adjacent battery cells, and the middle part is laser welded to the protruding portion 14.

[0038] Specifically, the upper cover 1 and the box body 2 are ultrasonically welded, and the lower cover 3 and the box body 2 are ultrasonically welded.

[0039] Specifically, the long side of the trapezoidal partition strip 7 is fixedly connected to the box body 2. Since the long side of the trapezoidal partition strip 7 is fixedly connected to the box body 2, when the battery cell is inserted between adjacent trapezoidal partition strips 7, it moves from the short side of the trapezoidal partition strip 7 to the long side. Therefore, there is a surplus space between the short side of the trapezoidal partition strip 7 and the battery cell, and this surplus space is used to solve the problem that the volume expansion of the battery cell after a failure causes extrusion of adjacent battery cells.

[0040] The specific embodiments described herein are merely illustrative of the spirit of the present invention. Those skilled in the art to which the present invention pertains can make various modifications or supplements to the described specific embodiments or use similar methods for substitution, but will not deviate from the spirit of the present invention or exceed the scope defined by the appended claims.

[0041] Although terms such as the upper cover 1, the box body 2, the lower cover 3, the opening 4, the installation cavity 5, the opening hole 6, the trapezoidal partition strip 7, the protection plate 8, the positioning post 9, the partition strip 10, the fixing buckle 11, the electrical connection device 12, the support portion 13, the protruding portion 14, and the mounting hole 15 are used more frequently in this article, the possibility of using other terms is not excluded. Using these terms is only for more conveniently describing and explaining the essence of the present invention; interpreting them as any additional limitation is contrary to the spirit of the present invention.

Claims

1. A battery box structure for a square battery cell, characterized in that, It includes an upper cover (1), a box body (2) and a lower cover (3). One end of the box body (2) is open (4). An installation cavity (5) for installing a battery cell is arranged inside the box body (2). Multiple openings (6) for exposing the lead electrodes of the battery cells are arranged at the other end of the box body (2). A trapezoidal partition strip (7) is arranged between adjacent openings (6). The trapezoidal partition strip (7) is located inside the box body (2). A protection board (8) is arranged between the upper cover (1) and the box body (2). The box body (2) is provided with positioning columns (9) for installing the protection board (8). After the protection board (8) is installed by the positioning columns (9), the upper ends of the positioning columns (9) are melted by ultrasonic heat fusion to fix the protection board (8). After the upper ends of the positioning columns (9) are heat-fused, fixing buckles (11) are formed. The fixing buckles (11) are buckled on the protection board (8). Electric connection devices (12) are arranged on both sides of the protection board (8). The two ends of the electric connection devices (12) are respectively electrically connected to the lead electrodes of adjacent battery cells. The electric connection devices (12) are connected to the protection circuit on the protection board (8). The electric connection devices (12) and the protection board (8) are laser welded.

2. The battery box structure for a square battery cell according to claim 1, wherein The lower cover (3) is provided with multiple partition strips (10) for separating each battery cell. The partition strips (10) correspond to the trapezoidal partition strips (7) one by one.

3. A battery box structure for a square battery cell according to claim 1, characterized in that, The box body (2) is also provided with a support portion (13) for supporting the protection board (8).

4. A battery box structure for a square battery cell according to claim 3, characterized in that, Multiple protruding portions (14) are arranged on both sides of the protection board (8). Mounting holes (15) are arranged on the protruding portions (14) corresponding to the positioning columns (9). The remaining protruding portions (14) are placed on the support portion (13).

5. The battery box structure for a square battery cell according to claim 1, wherein, The upper cover (1) and the box body (2) are ultrasonically welded. The lower cover (3) and the box body (2) are ultrasonically welded.

6. The battery box structure for a square battery cell according to claim 1, characterized in that, The long side of the trapezoidal partition strip (7) is fixedly connected to the box body (2).

Images