Lithium battery cover plate structure and secondary battery

Abstract

The utility model relates to a lithium battery cover plate structure and a secondary battery, and belongs to the field of new energy power batteries. The lithium battery cover plate assembly comprises a top cover plate with an electrode leading-out hole, and further comprises a pole which is positioned on one side of the top cover plate and covers the electrode leading-out hole, the limiting piece is connected with the top cover plate and at least partially surrounds the pole so as to limit the relative position of the pole on the top cover plate; and the fixing piece is connected with the top cover plate and at least partially surrounds the pole and the limiting piece, so that the pole and the limiting piece are fixed on the top cover plate, and the pole and the limiting piece are separated from each other. According to the cover plate structure, the limiting piece is connected with the top cover plate, the pole is limited, then the limiting piece and the pole are fixed through the fixing piece, the number of structural pieces is greatly reduced through the fixing structure and the connecting mode, the production and assembly difficulty is reduced, the production efficiency is improved, and meanwhile the production cost of the cover plate structure is reduced.

Description

Technical Field

[0001] The utility model relates to the field of new energy power batteries, and more specifically, to a lithium battery cover plate structure and a secondary battery. Background Art

[0002] In recent years, with the rapid growth of the global market for new energy vehicles, in order to meet people's demand for driving range, the requirement for the energy density of batteries has been increasing year by year, and at the same time, higher requirements have been put forward for the safety and lightweight of the cell structure design.

[0003] In the existing cover plate assembly, a through hole is provided on the top cover plate. The pole post is divided into a base part and an extension part, and the cross-sectional area of the base part is larger than the aperture of the through hole. During assembly, the base part is located on the side of the top cover plate close to the inside of the cell, the sealing ring is located between the base part and the top cover plate, and after the extension part passes through the through hole, the extension part is fixed by a snap ring or a riveting structure, so that the pole post is fixed on the top cover plate in this way. Since the base part is located inside the cell, it will occupy the internal space of the cell, thereby reducing the utilization rate of the internal space of the cell and further affecting the improvement of the battery energy density.

[0004] Therefore, there is an urgent need for a cover plate assembly that can use a shorter pole post that does not occupy the internal space of the cell, and at the same time can fix the pole post with a simple structure to prevent the shorter pole post from detaching from the top cover plate, thereby ensuring the reliability of battery use. Summary of the Utility Model

[0005] 1. Problems to be Solved

[0006] Aiming at the problem that when the shorter pole post and the end cover are connected by conventional connection methods such as riveting and snap ring connection in the prior art, the fixing force is insufficient and the pole post is prone to falling off, the utility model provides a lithium battery cover plate structure. When the height and weight of the terminal are reduced, the connection structure of the terminal is designed and simplified, and the pole post is firmly fixed on the end cover with a simple assembly process.

[0007] 2. Technical Solutions

[0008] To solve the above problems, the utility model adopts the following technical solutions.

[0009] A lithium battery cover plate structure includes a top cover plate having an electrode lead-out hole, and further includes: a pole post located on one side of the top cover plate and covering the electrode lead-out hole; a limiting member connected to the top cover plate, at least partially surrounding the pole post to limit the relative position of the pole post on the top cover plate; and a fixing member connected to the top cover plate, at least partially surrounding the pole post and the limiting member to fix the pole post and the limiting member on the top cover plate and separate the pole post and the limiting member from each other.

[0010] The lithium battery cover plate structure of the present invention is connected to the top cover plate through a limiting piece to limit the pole, and then the limiting piece and the pole are fixed by a fixing piece. This fixing structure and connection method greatly reduces the number of structural parts, reduces the difficulty of production and assembly, improves production efficiency, and also reduces the production cost of the cover plate structure.

[0011] In some embodiments, the fixing member has an annular base covering the top of the limiting member, a first extension portion, and a second extension portion; the first extension portion extends from the outer peripheral edge of the base toward the direction close to the top cover plate to wrap the outer peripheral surface of the limiting member; the second extension portion extends from the inner peripheral edge of the base toward the direction close to the top cover plate to separate the limiting member and the pole, and wrap the outer peripheral surface of the pole.

[0012] Furthermore, the pole has a flange facing the top cover plate, and the limiting member has a connecting portion connected to the top cover plate, and a cylindrical portion and an annular portion extending from the connecting portion in a direction away from the top cover plate, and limits the radial movement and axial movement of the pole by cooperating with the flange.

[0013] In some embodiments, a seal is provided between the top cover plate and the pole, and the edge of the seal abuts against the limiter and the fixing member to seal the gap between the top cover plate and the pole. The support member may be a sealing ring to ensure a good sealing effect.

[0014] Furthermore, the limiting member is connected to the top cover plate by welding. The limiting member can be a welding ring.

[0015] Furthermore, the fixing member is an insulating injection molded member, which is finally formed by insulating injection molding, thereby achieving fixation of the pole and the limiting member with a simple process method.

[0016] In some embodiments, a stop frame is provided on the side of the top cover plate facing away from the pole, and the stop frame is provided with a welding hole to cooperate with the electrode lead-out hole.

[0017] Furthermore, a connecting piece is provided on the side of the stopper away from the top cover plate. The connecting piece is provided with a raised positioning portion that passes through the welding hole and the electrode lead-out hole, and is connected to the terminal. The cooperation between the raised positioning portion and the welding hole and the electrode lead-out hole can achieve the effect of positioning the connecting piece.

[0018] Furthermore, the stop frame is provided with a positioning post on one side of the connecting piece, and the connecting piece is provided with a positioning hole that cooperates with the positioning post for positioning, so as to further achieve fast and accurate positioning and installation of the connecting piece and avoid deviation of the connecting piece.

[0019] A secondary battery includes a housing with at least one open end, a battery cell is disposed inside the housing, and the above-mentioned lithium battery cover structure is provided at the opening of the housing, wherein the connecting piece is electrically connected to the battery cell.

[0020] Obviously, the elements or features described in the above single embodiment can be used alone or in combination in other embodiments.

[0021] 3. Beneficial effects

[0022] Compared with the prior art, the beneficial effects of the present utility model are as follows:

[0023] (1) A lithium battery cover structure provided by the present utility model is connected to the top cover plate through a limiting member to limit the pole column, and then the limiting member and the pole column are fixed through a fixing member. This fixing structure and connection method greatly reduce the number of structural parts, lower the production and assembly difficulty, improve the production efficiency, and reduce the production cost of the cover structure at the same time.

[0024] (2) A lithium battery cover structure provided by the present utility model, the fixing member composed of a base portion, a first extension portion and a second extension portion can limit the movement of the limiting member and the pole column in the radial direction and the axial direction of the pole column with one structural part, simplifies the assembly process, and can completely separate the limiting member and the pole column through the second extension portion to ensure the insulation effect.

[0025] (3) A lithium battery cover structure provided by the present utility model can enhance the sealing effect by setting a sealing member, making the overall cover structure more compact.

[0026] (4) A lithium battery cover structure provided by the present utility model, a positioning protrusion portion is provided on the connecting piece, which can cooperate with the welding hole and the electrode lead-out hole to achieve the effect of positioning and installing the connecting piece. A positioning column is provided on the stop frame, and a positioning hole for cooperating with the positioning column is provided on the connecting piece, which can not only further achieve the quick and accurate positioning and installation of the connecting piece, but also avoid the deviation of the connecting piece during the installation process. Description of the drawings

[0027] In the drawings, the dimensions and ratios do not represent the dimensions and ratios of the actual product. The drawings are merely illustrative, and for the sake of clarity, some non-essential elements or features are omitted.

[0028] Figure 1 It is a schematic diagram of the structural composition of the lithium battery cover structure in Embodiment 1;

[0029] Figure 2 It is an assembly schematic diagram of the lithium battery cover structure in Embodiment 1;

[0030] Figure 3Schematic diagram of the limiting part and pole column assembly of the lithium battery cover plate structure in Embodiment 1;

[0031] Figure 4 Schematic diagram of the structure of the limiting part in the lithium battery cover plate structure in Embodiment 1;

[0032] Figure 5 Schematic diagram of the completed structure of the lithium battery cover plate structure in Embodiment 1;

[0033] Figure 6 Schematic diagram of the structure of the lithium battery cover plate structure without the pole column assembled in Embodiment 1;

[0034] Figure 7 Schematic diagram of the structure of the lithium battery cover plate structure assembled with the connecting piece in Embodiment 1;

[0035] Figure 8 Schematic diagram of the structure of the connecting piece in the lithium battery cover plate structure in Embodiment 1;

[0036] Figure 9 Cross-sectional view of the connecting piece in the lithium battery cover plate structure in Embodiment 1.

[0037] Description of reference numerals

[0038] 100, top cover plate; 101, electrode lead-out hole; 200, pole column; 201, flange; 300, limiting part; 301, connecting part; 302, cylindrical part; 303, annular part; 400, fixing part; 401, base part; 402, first extension part; 403, second extension part; 500, sealing part; 600, stop frame; 601, welding hole; 602, positioning column; 700, connecting piece; 701, convex positioning part; 702, positioning hole. Detailed implementation manners

[0039] Next, the present utility model will be described in detail with reference to the accompanying drawings. What is described here is only the preferred implementation manner of the present utility model. Those skilled in the art can think of other ways to implement the present utility model based on the preferred implementation manner, and such other ways also fall within the scope of the present utility model.

[0040] Embodiment 1

[0041] This embodiment provides a lithium battery cover plate structure, which is mainly applied to secondary batteries or lithium batteries. This lithium battery cover plate structure can be assembled at the opening of the battery case, and is applicable to both batteries with one end open and batteries with both ends open.

[0042] As Figure 1 , Figure 2 and Figure 5As shown in the figure, the structure of the lithium battery cover plate mainly includes a top cover plate 100, a pole column 200 assembled on the top cover plate 100, and a connecting structural member between the two.

[0043] An electrode lead-out hole 101 is provided on the top cover plate 100. The pole column 200 is located on one side of the top cover plate 100 and covers the electrode lead-out hole 101. A limiting member 300 is also provided on the same side of the top cover plate 100. The limiting member 300 is connected to the top cover plate 100 and at least partially surrounds the pole column 200, thereby restricting the relative position of the pole column 200 on the top cover plate 100. In addition, a fixing member 400 is also provided on the same side of the top cover plate 100. The fixing member 400 is connected to the top cover plate 100 and at least partially surrounds the pole column 200 and the limiting member 300, thereby fixing the pole column 200 and the limiting member 300 on the top cover plate 100. A part of the fixing member 400 is filled between the pole column 200 and the limiting member 300, so that the pole column 200 and the limiting member 300 are separated from each other, thereby ensuring the insulation effect.

[0044] In the structure of the lithium battery cover plate of this embodiment, the limiting member 300 is connected to the top cover plate 100 to limit the pole column 200, and then the limiting member 300 and the pole column 200 are fixed by the fixing member 400. This fixing structure and connection method greatly reduce the number of structural members, reduce the production and assembly difficulty, improve the production efficiency, and at the same time reduce the production cost of the cover plate structure.

[0045] In a possible implementation manner, the fixing member 400 has an annular base portion 401, a first extension portion 402, and a second extension portion 403. The annular base portion 401 covers the top of the limiting member 300. The first extension portion 402 extends from the outer peripheral edge of the base portion 401 towards the top cover plate 100 to wrap the outer peripheral surface of the limiting member 300, thereby restricting the radial movement of the limiting member 300 and the pole column 200. The second extension portion 403 extends from the inner peripheral edge of the base portion 401 towards the top cover plate 100 to separate the limiting member 300 and the pole column 200 and wrap the outer peripheral surface of the pole column 200, thereby ensuring the insulation effect and firmly fixing the pole column 200 and the limiting member 300 on the top cover plate 100. In a further possible embodiment, the fixing member 400 can be an insulating injection molded part, that is, the fixing member 400 is formed by an insulating injection molding method, so that the limiting member 300 and the pole column 200 can be fixed by a simpler process.

[0046] Regarding the further design of the limiting member 300, in a possible implementation manner, as Figure 3 and 4As shown, the terminal post 200 has a flange 201 facing the top cover plate 100. The limiting member 300 has a connecting portion 301 connected to the top cover plate 100, and a cylindrical portion 302 and an annular portion 303 extending from the connecting portion 301 away from the top cover plate 100. The two cooperate with the flange 201. The cylindrical portion 302 can limit the radial movement of the terminal post 200, and the annular portion 303 and the top cover plate 100 cooperate to clamp the flange 201 to limit the axial movement of the terminal post 200. With such a setting, the overall structure of the cover plate can be made more compact and stable. In a further possible embodiment, the limiting member 300 can be connected to the top cover plate 100 by welding.

[0047] In a possible implementation manner, the top cover plate 100 is provided with a groove around the terminal post 200, the limiting member 300 and the fixing member 400. The groove can accommodate the contact portions of the fixing member 400, the limiting member 300, the terminal post 200 and the top cover plate 100. Specifically, the outer peripheral edge of the connecting portion 301 of the limiting member 300 is welded to the inner side wall of the groove, and the fixing member 400 formed by insulating injection molding fills the remaining gaps in the groove, which can improve the integrity and aesthetics of the overall structure of the cover plate.

[0048] Furthermore, in order to ensure the sealing effect at the connection of the terminal post 200, a sealing member 500 is provided between the terminal post 200 and the top cover plate 100. The edge of the sealing member 500 abuts against the limiting member 300 and the fixing member 400, while ensuring the sealing effect, improving the compactness of the overall connection structure.

[0049] Before installing the cover plate structure on the opening of the battery case, it is also necessary to set a stop bracket 600. That is, a stop bracket 600 is provided on the side of the top cover plate 100 facing away from the terminal post 200. As Figure 6 shown, the stop bracket 600 is provided with a welding hole 601 in cooperation with the electrode lead-out hole 101.

[0050] When assembling the cover plate structure, it is necessary to electrically connect the battery cell connecting piece 700 to the terminal post 200. In this process, it often occurs that it is difficult to accurately position, resulting in difficulties in the assembly process. For this reason, in a possible embodiment, as Figures 6-9 shown, a connecting piece 700 is also provided on the side of the stop bracket 600 facing away from the top cover plate 100. The connecting piece 700 is provided with a protruding positioning portion 701 passing through the welding hole 601 and the electrode lead-out hole 101. The protruding positioning portion 701 is connected to the terminal post 200, so as to achieve the effect of quickly positioning the installation of the connecting piece 700.

[0051] For further improvement of this embodiment, a positioning post 602 is provided on the side of the stop bracket 600 facing the connecting piece 700, and a positioning hole 702 for cooperating with the positioning post 602 is provided on the connecting piece 700. It can further achieve the quick and accurate positioning installation of the connecting piece 700 and prevent the connecting piece 700 from shifting.

[0052] Embodiment 2

[0053] This embodiment provides a secondary battery, which is mainly applied to new energy power battery modules. Multiple secondary batteries can form a large power battery module, so as to provide power for equipment such as new energy vehicles.

[0054] The secondary battery includes a housing with at least one open end. A battery cell is arranged inside the housing, and the lithium battery cover structure in Embodiment 1 is arranged at the opening of the housing. The battery cell leads out electricity through the connecting piece 700 at the end.

[0055] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "front", "rear", "left", "right", "upper", "lower", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings. It is 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, so it cannot be understood as a limitation to the present invention.

[0056] In the description of the present invention, it should be noted that unless otherwise clearly specified and limited, the terms "installation", "connection", and "connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0057] The protection scope of the present invention is only defined by the claims. Benefiting from the teachings of the present invention, those skilled in the art can easily recognize that alternative structures of the structures disclosed in the present invention can be used as feasible alternative embodiments, and the embodiments disclosed in the present invention can be combined to produce new embodiments, which also fall within the scope of the appended claims.

Claims

1. A lithium battery cover plate structure, comprising a top cover plate (100) having an electrode lead-out hole (101), characterized in that, Also includes: A pole (200) is located on one side of the top cover plate (100) and covers the electrode lead-out hole (101); a limiting member (300), the limiting member (300) being connected to the top cover plate (100) and at least partially surrounding the pole (200) to limit the relative position of the pole (200) on the top cover plate (100); A fixing member (400) is connected to the top cover plate (100) and at least partially surrounds the pole (200) and the limiting member (300) to fix the pole (200) and the limiting member (300) on the top cover plate (100) and to separate the pole (200) and the limiting member (300) from each other.

2. The lithium battery cover plate structure according to claim 1, wherein: The fixing member (400) comprises an annular base (401) covering the top of the limiting member (300), a first extending portion (402) and a second extending portion (403); The first extension portion (402) extends from the outer peripheral edge of the base portion (401) toward the top cover plate (100) to wrap around the outer peripheral surface of the limiting member (300); The second extension portion (403) extends from the inner peripheral edge of the base portion (401) toward the top cover plate (100) to separate the limiting member (300) and the pole (200) and wrap the outer peripheral surface of the pole (200).

3. The lithium battery cover plate structure according to claim 1, characterized in that: The pole (200) has a flange (201) facing the top cover plate (100), and the limiting member (300) has a connecting portion (301) connected to the top cover plate (100), and a cylindrical portion (302) and an annular portion (303) extending from the connecting portion (301) in a direction away from the top cover plate (100), and limits the radial movement and axial movement of the pole (200) by cooperating with the flange (201).

4. The lithium battery cover plate structure according to claim 1, wherein: A sealing member (500) is provided between the top cover plate (100) and the pole (200), and an edge of the sealing member (500) abuts against the limiting member (300) and the fixing member (400).

5. The lithium battery cover plate structure according to claim 1, wherein: The limiting member (300) is connected to the top cover plate (100) by welding.

6. The lithium battery cover plate structure according to claim 1, wherein: The fixing part (400) is an insulating injection molded part.

7. The lithium battery cover plate structure according to any one of claims 1-6, characterized in that: A stop frame (600) is provided on the side of the top cover plate (100) facing away from the pole (200), and the stop frame (600) is provided with a welding hole (601) in cooperation with the electrode lead-out hole (101).

8. The structure of the lithium battery cover plate according to claim 7, characterized in that: A connecting piece (700) is provided on the side of the stop frame (600) facing away from the top cover plate (100), and a protruding positioning portion (701) passing through the welding hole (601) and the electrode lead-out hole (101) is provided on the connecting piece (700), and the protruding positioning portion (701) is connected to the pole (200).

9. The structure of the lithium battery cover plate according to claim 8, wherein: A positioning column (602) is provided on one side of the stop frame (600) facing the connecting piece (700), and a positioning hole (702) is provided on the connecting piece (700) for cooperating with the positioning column (602) for positioning.

10. A secondary battery, comprising a housing with at least one open end, and an electrode assembly disposed within the housing, characterized in that, The lithium battery cover structure according to any one of claims 8 to 9 is provided at the shell opening, wherein the connecting piece (700) is electrically connected to the battery cell.

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