Protective structure of lithium battery connecting piece and lithium battery

Abstract

The utility model discloses a protection structure of a lithium battery connecting piece and a lithium battery, and belongs to the technical field of lithium batteries. The protection structure is used for being arranged between an electrode connecting piece and the inner wall of a battery shell and comprises a positioning stop frame, a plurality of positioning structures are arranged on the side, making contact with the electrode connecting piece, of the positioning stop frame, and the positioning stop frame and the electrode connecting piece are kept fixed through the positioning structures. The lithium battery comprises a cover plate assembly, an electrode connecting piece, a battery cell, a shell and the protection structure, the electrode connecting piece is connected with the cover plate assembly and the battery cell, the battery cell is installed in the shell, the cover plate assembly seals the shell, the electrode connecting piece is provided with a plurality of positioning holes, and the positioning structure and the positioning holes are installed in a matched mode. Compared with the prior art, the positioning stop frame is fixed with the electrode connecting sheet through the positioning structure, replaces a rubberizing protection measure, is not easy to fall off, has better stability and can improve the safety of the battery.

Description

Technical Field

[0001] The utility model relates to the technical field of lithium batteries, in particular to a protection structure of a lithium battery connecting piece and a lithium battery. Background Art

[0002] Power batteries have been widely used in new energy vehicles, energy storage equipment and other products. Taking lithium-ion batteries as an example, they include a shell, a core and a cover. The core includes a positive electrode sheet, a diaphragm and a negative electrode sheet. The positive electrode sheet and the negative electrode sheet are separated by a diaphragm. There are protruding parts of the positive electrode sheet foil and the negative electrode sheet foil on both sides of the core. The core is welded between the positive and negative L-shaped connecting sheets, and then placed inside the shell, and sealed by the cover plate to form a battery.

[0003] The connecting piece is a common component of lithium batteries. For example, the Chinese patent document with publication number CN109860447A discloses an L-shaped connecting piece bipolar column lithium battery cover plate, in which the positive connecting piece and the negative connecting piece are welded under the positive rivet and the negative rivet respectively, and the positive connecting piece and the negative connecting piece are respectively located at the bottom of the aluminum shell. The connecting piece in the patent document is placed in the battery shell. Considering the insulation between the connecting piece and the battery shell, a protective device is generally provided on the connecting piece. At present, the protective measures for the connecting piece are mostly in the form of adhesive tape. On the one hand, the tape is easy to fall off after being immersed in the electrolyte for a long time. On the other hand, the tape is relatively soft, and the vibration makes the protective structure unstable, which increases the risk of the battery cell shaking left and right in the shell, increasing the safety risk during the use of the battery. Utility Model Content

[0004] 1. Technical problems to be solved by the utility model

[0005] In view of the problem that the protective structure of the battery connecting piece in the prior art mostly adopts the glue sticking method, which makes the protective structure easy to fall off and unstable, the utility model proposes a protective structure for the lithium battery connecting piece, in which the positioning stop frame is fixed to the electrode connecting piece through the positioning structure, is not easy to fall off and has better stability.

[0006] The utility model also provides a lithium battery, which adopts the above protection structure.

[0007] 2. Technical solution

[0008] In order to achieve the above-mentioned purpose, the utility model provides a protective structure for a lithium battery connecting piece, which is used to be arranged between the electrode connecting piece and the inner wall of the battery shell, including a positioning stop frame, and a plurality of positioning structures are arranged on the side of the positioning stop frame in contact with the electrode connecting piece, and the positioning structures keep the positioning stop frame and the electrode connecting piece fixed.

[0009] Furthermore, the positioning structure is a buckle protruding toward the position of the electrode connecting piece.

[0010] Furthermore, at least two buckles are provided.

[0011] Furthermore, a reinforcement structure is provided on one side of the positioning and stopping frame facing the inner wall of the battery housing, and the reinforcement structure supports the frame body of the positioning and stopping frame.

[0012] Furthermore, the reinforcement structure includes a plurality of crisscross reinforcement ribs, and the reinforcement ribs are distributed in the length and width directions of the positioning stop frame.

[0013] Furthermore, a protruding step is provided on the top of the positioning and stopping frame on the side facing the electrode connecting piece, and the step leaves a gap between the positioning and stopping frame and the electrode connecting piece when the positioning and stopping frame and the electrode connecting piece are fixed.

[0014] The utility model also provides a lithium battery, including a cover plate assembly, an electrode connecting piece, a battery cell, a shell and the above-mentioned protective structure, the electrode connecting piece connects the cover plate assembly and the battery cell, the battery cell is installed in the shell, the cover plate assembly closes the shell, the electrode connecting piece is provided with a plurality of positioning holes, and the positioning structure is installed in cooperation with the positioning holes.

[0015] Furthermore, the tabs of the battery cell are connected to the electrode connecting sheet and extend into the gap between the positioning stop frame and the electrode connecting sheet.

[0016] Furthermore, it also includes an insulating layer, which isolates the positioning stop frame and the battery core from the inner wall of the shell.

[0017] Furthermore, the insulating layer is a flexible structure, and the insulating layer is wrapped around the outer side of the positioning and stopping frame and the battery core.

[0018] 3. Beneficial effects

[0019] Compared with the existing known technologies, the technical solution provided by the utility model has the following beneficial effects:

[0020] (1) The utility model provides a protective structure for a lithium battery connecting piece, wherein the positioning stop frame is fixed to the electrode connecting piece through the positioning structure, replacing the adhesive-type protective measure, is not easy to fall off and has better stability, thereby improving the safety of the battery.

[0021] (2) The utility model provides a protective structure for a lithium battery connector. The positioning mechanism adopts a buckle structure, which can produce a good connection with the electrode connector, and at least two buckles can increase the stability of the connection and reduce the risk of the buckles falling off. A reinforcement structure is provided on one side of the positioning stop frame to support the positioning stop frame. The reinforcement structure adopts criss-cross reinforcement ribs, which is conducive to improving the structural strength of the positioning stop frame and reducing the overall deformation of the positioning stop frame.

[0022] (3) The utility model provides a protective structure for a lithium battery connecting piece. The positioning stop frame has a step structure so that when the positioning stop frame is fixed to the electrode connecting piece, a gap can be left between the positioning stop frame and the electrode connecting piece. The gap can accommodate the pole ear led out of the battery cell, which not only avoids the pole ear being exposed to the outside and contacting the shell, but also reduces the extra space occupied, thereby saving space in the battery shell. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In the drawings, the sizes and proportions do not represent the sizes and proportions of actual products. The drawings are merely illustrative, and some non-essential elements or features are omitted for clarity.

[0024] Figure 1 It is a structural schematic diagram of the protective structure of an embodiment of the utility model;

[0025] Figure 2 This is a schematic structural diagram of the connection state of the protection structure and the electrode connecting piece of the embodiment of the utility model;

[0026] Figure 3 It is a structural explosion view of a lithium battery according to an embodiment of the present utility model.

[0027] Explanation of the symbols in the schematic diagram:

[0028] 1. Positioning stop frame; 101. Positioning structure; 102. Reinforcement structure; 103. Step; 2. Cover plate assembly; 3. Electrode connecting piece; 301. Positioning hole; 4. Battery cell; 5. Shell; 6. Insulation layer. DETAILED DESCRIPTION

[0029] In order to further understand the content of the utility model, the utility model is described in detail in conjunction with the accompanying drawings and embodiments. What is described here is only the preferred embodiment of the utility model. Those skilled in the art can think of other ways to implement the utility model based on the preferred embodiment, and other ways also fall within the scope of the utility model.

[0030] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "inner", "outer", "top", "bottom", "side", "vertical", "horizontal" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0031] Example

[0032] Reference Figure 1-Figure 3 The present embodiment provides a protective structure for a lithium battery connecting piece, which is used to be arranged between the electrode connecting piece 3 and the inner wall of the battery housing 5, and includes a positioning stop frame 1. The side of the positioning stop frame 1 in contact with the electrode connecting piece 3 is provided with a plurality of positioning structures 101, and the positioning structure 101 keeps the positioning stop frame 1 and the electrode connecting piece 3 fixed. The positioning stop frame 1 can still remain fixed to the electrode connecting piece 3 after being immersed in the electrolyte for a long time. Compared with the glue sticking method, it is more stable and not easy to fall off. Moreover, the positioning stop frame 1 is made of PP material, which is harder than tape, can better cope with the vibration generated during the use of the battery, has better stability, can reduce the risk of shaking of the battery cell 4, and improve the safety of battery use.

[0033] like Figure 1 and Figure 2 As shown, the positioning structure 101 is a buckle protruding toward the direction of the position of the electrode connecting piece 3. The structure of the buckle is a column, and a groove is provided at the end of the column. The groove divides the end into a number of extrudable parts. When the end of the buckle is inserted into the positioning hole 301 of the electrode connecting piece 3, the end first contracts along the groove and then opens along the groove, and the end of the buckle is engaged with the positioning hole 301. The groove can be a straight groove or a cross groove. In this embodiment, there are four buckles, and the four buckles are respectively located at the four corners of the positioning stop frame 1. The structure and number of the buckles can increase the stability of the connection and reduce the risk of the buckles falling off. It is worth emphasizing that the number of buckles can also be two, three or even more than four, but it is most preferred to set four.

[0034] Since the positioning stop frame 1 is made of PP material, there are certain requirements on the structural strength of the positioning stop frame 1. Figure 1 and Figure 2 As shown, a reinforcement structure 102 is provided on one side of the positioning and stopping frame 1 facing the inner wall of the battery housing 5, and the reinforcement structure 102 supports the frame body of the positioning and stopping frame 1. The reinforcement structure 102 includes a plurality of crisscross reinforcement ribs, which are distributed in the length and width directions of the positioning and stopping frame 1, which is beneficial to improving the structural strength of the positioning and stopping frame 1 and reducing the overall deformation of the positioning and stopping frame 1.

[0035] A protruding step 103 is provided on the top of the positioning stop frame 1 facing the electrode connecting sheet 3. When the positioning stop frame 1 and the electrode connecting sheet 3 are fixed, the step 103 leaves a gap between the positioning stop frame 1 and the electrode connecting sheet 3. The gap can accommodate the tabs led out of the battery cell 4, which not only prevents the tabs from being exposed to the outside and contacting the housing 5, but also reduces the extra space occupied, saving space in the battery housing 5.

[0036] like Figure 3As shown, the present application also provides a lithium battery, including a cover plate assembly 2, an electrode connecting sheet 3, a battery cell 4, a shell 5 and the above-mentioned protective structure, the electrode connecting sheet 3 connects the cover plate assembly 2 and the battery cell 4, the battery cell 4 is installed in the shell 5, the cover plate assembly 2 closes the shell 5, the electrode connecting sheet 3 is provided with a plurality of positioning holes 301, and the positioning structure 101 is installed in cooperation with the positioning holes 301. It should be noted that the structure of the cover plate assembly 2 is a common cover plate structure, including a substrate, a positive electrode rivet, a negative electrode rivet and an explosion-proof valve, and the specific structure is not repeated here.

[0037] Furthermore, the tabs of the battery cell 4 are connected to the electrode connecting sheet 3 and extend into the gap between the positioning stop frame 1 and the electrode connecting sheet 3. The gap between the positioning stop frame 1 and the electrode connecting sheet 3 is greater than the thickness of the tabs of the battery cell 4 to prevent the tabs from being squeezed. On the other hand, the tabs of the battery cell 4 are laser welded to the electrode connecting sheet 3, leaving laser welding marks on the electrode connecting sheet 3, and the presence of the positioning stop frame 1 can cover the laser welding marks.

[0038] like Figure 3 As shown, the lithium battery also includes an insulating layer 6, which blocks the positioning stop frame 1 together with the battery cell 4 from the inner wall of the shell 5, maintains the insulation between the battery cell 4 and the shell 5, and prevents leakage. Specifically, the insulating layer 6 is a flexible structure, and the insulating layer 6 is wrapped around the outside of the positioning stop frame 1 and the battery cell 4. Preferably, the insulating layer 6 of this embodiment adopts a flexible PP tape, and the PP tape is wrapped around the outside of the positioning stop frame 1 and the battery cell 4. In addition, the insulating layer 6 can be made of rubber material, and the rubber material is processed into a thinner structure, such as a film, and wrapped around the outside of the battery cell 4. The rubber material needs to be a rubber resistant to electrolyte, such as a fluororubber material.

[0039] The above schematically describes the present invention and its implementation methods, which are not restrictive. The drawings show only one implementation method of the present invention, and the actual structure is not limited thereto. Therefore, if ordinary technicians in this field are inspired by it and design structural methods and embodiments similar to the technical solution without creativity without departing from the purpose of the present invention, they should all fall within the protection scope of the present invention.

Claims

1. A protective structure for a lithium battery connecting piece, used to be arranged between an electrode connecting piece (3) and an inner wall of a battery housing (5), characterized in that: It comprises a positioning stop frame (1), wherein a side of the positioning stop frame (1) in contact with the electrode connecting piece (3) is provided with a plurality of positioning structures (101), wherein the positioning structures (101) keep the positioning stop frame (1) and the electrode connecting piece (3) fixed.

2. The protective structure of a lithium battery connecting piece according to claim 1, characterized in that: The positioning structure (101) is a buckle that protrudes in the direction of the location of the electrode connecting sheet (3).

3. A protective structure for a lithium battery connecting piece according to claim 2, characterized in that: At least two buckles are provided.

4. The protective structure of a lithium battery connecting piece according to claim 1, characterized in that: A reinforcing structure (102) is provided on one side of the positioning and stopping frame (1) facing the inner wall of the battery housing (5), and the reinforcing structure (102) supports the frame body of the positioning and stopping frame (1).

5. The protective structure of a lithium battery connecting piece according to claim 4, characterized in that: The reinforcement structure (102) comprises a plurality of crisscross reinforcement ribs, wherein the reinforcement ribs are distributed in the length and width directions of the positioning stop frame (1).

6. The protective structure of a lithium battery connecting piece according to claim 1, characterized in that: A protruding step (103) is provided on the top of the positioning stop frame (1) on the side facing the electrode connecting piece (3); the step (103) leaves a gap between the positioning stop frame (1) and the electrode connecting piece (3) when the positioning stop frame (1) and the electrode connecting piece (3) are fixed.

7. A lithium battery, characterized in that: The invention comprises a cover plate assembly (2), an electrode connecting sheet (3), a battery cell (4), a shell (5) and a protective structure according to any one of claims 1 to 6, wherein the electrode connecting sheet (3) connects the cover plate assembly (2) and the battery cell (4), the battery cell (4) is installed in the shell (5), the cover plate assembly (2) closes the shell (5), the electrode connecting sheet (3) is provided with a plurality of positioning holes (301), and the positioning structure (101) is installed in cooperation with the positioning holes (301).

8. A lithium battery according to claim 7, characterized in that: The pole lug of the battery core (4) is connected to the electrode connecting sheet (3) and extends into the gap between the positioning stop frame (1) and the electrode connecting sheet (3).

9. A lithium battery according to claim 7, characterized in that: It also includes an insulating layer (6), wherein the insulating layer (6) isolates the positioning stop frame (1) together with the battery core (4) from the inner wall of the housing (5).

10. A lithium battery according to claim 9, characterized in that: The insulating layer (6) is a flexible structure, and the insulating layer (6) is wrapped around the outer sides of the positioning stop frame (1) and the battery core (4).

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