Lithium battery cover plate structure and secondary battery

Abstract

The present application relates to the field of new energy power batteries, and relates to a lithium battery cover plate structure and a secondary battery. The lithium battery cover plate assembly comprises a top cover plate (100) having electrode lead-out holes (101), and further comprises: poles (200) located on one side of the top cover plate (100) and covering the electrode lead-out holes (101); limiting members (300) connected to the top cover plate (100), wherein the limiting members (300) at least partially surround the poles (200) so as to limit the relative positions of the poles (200) on the top cover plate (100); and fixing members (400) connected to the top cover plate (100), wherein fixing members (400) at least partially surround the poles (200) and the limiting members (300), so as to fix the poles (200) and the limiting members (300) on the top cover plate (100) and to separate the poles (200) and the limiting members (300) from each other. The limiting members (300) are connected to the top cover plate (100) so as to limit the poles (200), and the limiting members (300) and the poles (200) are fixed by means of the fixing members (400). Such fixing structure and connection method greatly reduce the number of structural members, reduce the production and assembly difficulty, improve the production efficiency, and also reduce the production cost of the cover plate structure.

Description

Lithium battery cover structure and secondary battery Technical Field

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

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

[0003] In existing cover plate assemblies, the top cover plate is provided with a through-hole. The pole is divided into a base portion and an extension portion. The cross-sectional area of ​​the base portion is larger than the diameter of the through-hole. During assembly, the base portion is located on the side of the top cover plate closest to the interior of the battery cell, with a sealing ring positioned between the base portion and the top cover plate. After the extension portion passes through the through-hole, a retaining spring or riveting structure is used to secure the extension portion, thereby securing the pole to the top cover plate. Because the base portion is located inside the battery cell, it occupies the internal space of the battery cell, reducing the utilization rate of the internal space and further affecting the improvement of the battery's energy density.

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

[0005] Utility Model Content

[0006] 1. Problems to be solved

[0007] In view of the problem in the prior art that the shorter pole and the end cover are connected by conventional riveting and spring connection, the fixing force is insufficient and the pole is easy to fall off. The utility model provides a lithium battery cover plate structure. While reducing the height and weight of the terminal, the terminal connection structure is designed and simplified, and the pole is firmly fixed to the end cover with a simple assembly process.

[0008] 2. Technical solution

[0009] In order to solve the above problems, the present invention adopts the following technical solutions.

[0010] A lithium battery cover plate structure includes a top cover plate with an electrode lead-out hole, and also includes: a pole 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, which at least partially surrounds the pole to limit the relative position of the pole on the top cover plate; and a fixing member connected to the top cover plate, which at least partially surrounds the pole and the limiting member to fix the pole and the limiting member to the top cover plate and separate the pole and the limiting member from each other.

[0011] 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.

[0012] 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.

[0013] 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.

[0014] 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.

[0015] Furthermore, the limiting member is connected to the top cover plate by welding. The limiting member can be a welding ring.

[0016] 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.

[0017] 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.

[0018] 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.

[0019] 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.

[0020] A secondary battery comprises a shell with at least one end open, a battery cell arranged in the shell, the above-mentioned lithium battery cover plate structure is arranged at the shell opening, and the connecting piece is electrically connected to the battery cell.

[0021] It will be apparent that elements or features described above in connection with a single embodiment may be used alone or in combination in other embodiments.

[0022] 3. Beneficial effects

[0023] Compared with the prior art, the beneficial effects of the present invention are:

[0024] (1) The present invention provides a lithium battery cover plate structure, which is connected to the top cover plate through a limiting member to limit the pole, and then the limiting member and the pole are fixed by a fixing member. 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.

[0025] (2) The present invention provides a lithium battery cover structure, which is a fixing member composed of a base, a first extension part, and a second extension part. A single structural member can limit the movement of the limiter and the pole in the radial and axial directions of the pole, thereby simplifying the assembly process. The limiter and the pole can be completely separated by the second extension part to ensure the insulation effect.

[0026] (3) The present invention provides a lithium battery cover structure, which can enhance the sealing effect by providing a sealing member, making the cover structure more compact as a whole.

[0027] (4) The present invention provides a lithium battery cover plate structure, in which a positioning protrusion is provided on the connecting plate, which can cooperate with the welding hole and the electrode lead-out hole to achieve the effect of positioning and installing the connecting plate. A positioning column is provided on the stop frame, and a positioning hole cooperating with the positioning column is provided on the connecting plate, which can further achieve rapid and accurate positioning and installation of the connecting plate and avoid displacement of the connecting plate during the installation process. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] 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.

[0029] FIG1 is a schematic diagram of the structure of the lithium battery cover plate structure in Example 1;

[0030] FIG2 is a schematic diagram of the assembly of the lithium battery cover structure in Example 1;

[0031] FIG3 is a schematic diagram of the assembly of the limiting member and the pole of the lithium battery cover structure in Example 1;

[0032] FIG4 is a schematic structural diagram of a position-limiting member in the lithium battery cover structure in Example 1;

[0033] FIG5 is a schematic diagram of the structure of the lithium battery cover plate structure after assembly in Example 1;

[0034] FIG6 is a schematic structural diagram of a lithium battery cover structure without poles in Example 1;

[0035] FIG7 is a schematic diagram of the structure of the lithium battery cover plate structure assembled with the connecting piece in Example 1;

[0036] FIG8 is a schematic structural diagram of the connecting piece in the lithium battery cover structure in Example 1;

[0037] FIG9 is a cross-sectional view of the connecting piece in the lithium battery cover structure in Example 1.

[0038] Explanation of the reference numerals: 100, top cover plate; 101, electrode lead-out hole; 200, pole; 201, flange; 300, limiter; 301, connecting portion; 302, cylindrical portion; 303, annular portion; 400, fixing member; 401, base; 402, first extension portion; 403, second extension portion; 500, sealing member; 600, stop frame; 601, welding hole; 602, positioning column; 700, connecting piece; 701, raised positioning portion; 702, positioning hole. DETAILED DESCRIPTION

[0039] The present invention will be described in detail below with reference to the accompanying drawings. What is described here is merely a preferred embodiment of the present invention, and those skilled in the art may conceive of other methods for implementing the present invention based on the preferred embodiment, and such other methods also fall within the scope of the present invention.

[0040] Example 1

[0041] This embodiment provides a lithium battery cover plate structure, which is mainly used in secondary batteries or lithium batteries. The lithium battery cover plate structure can be assembled at the opening of the battery shell and is applicable to batteries with one end open as well as batteries with two ends open.

[0042] As shown in FIG1 , FIG2 and FIG5 , the lithium battery cover plate structure mainly includes a top cover plate 100 , a pole 200 assembled on the top cover plate 100 , and a connecting structure therebetween.

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

[0044] The lithium battery cover plate structure of this embodiment is connected to the top cover plate 100 through a limiting member 300, which limits the pole 200, and then fixed by a fixing member 400. 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.

[0045] In one possible embodiment, the fixing member 400 includes an annular base 401, a first extension 402, and a second extension 403. The annular base 401 covers the top of the stopper 300. The first extension 402 extends from the outer peripheral edge of the base 401 toward the top cover plate 100 to wrap around the outer peripheral surface of the stopper 300, thereby limiting radial movement of the stopper 300 and the pole 200. The second extension 403 extends from the inner peripheral edge of the base 401 toward the top cover plate 100 to separate the stopper 300 from the pole 200 and wrap around the outer peripheral surface of the pole 200, thereby ensuring insulation and firmly fixing the pole 200 and the stopper 300 to the top cover plate 100. In a further possible embodiment, the fixing member 400 may be an insulating injection molded part, that is, formed by insulating injection molding, so that the stopper 300 and the pole 200 can be fixed using a simpler process.

[0046] Regarding the further design of the limiter 300, in one possible embodiment, as shown in Figures 3 and 4, the pole 200 has a flange 201 facing the top cover plate 100, and the limiter 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. The two cooperate with the flange 201, and the cylindrical portion 302 can limit the radial movement of the pole 200. The annular portion 303 and the top cover plate 100 cooperate to clamp the flange 201 to limit the axial movement of the pole 200. Such an arrangement can make the overall structure of the cover plate more compact and stable. In a further possible embodiment, the limiter 300 can be connected to the top cover plate 100 by welding.

[0047] In one possible embodiment, the top cover plate 100 is provided with a groove surrounding the pole 200, the stopper 300, and the fixing member 400. The groove can accommodate the contact portions of the fixing member 400, the stopper 300, the pole 200, and the top cover plate 100. Specifically, the outer peripheral edge of the connecting portion 301 of the stopper 300 is welded to the inner sidewall of the groove, and the fixing member 400 formed by insulating injection molding fills the remaining gap in the groove, which can improve the integrity and aesthetics of the overall cover plate structure.

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

[0049] Before the cover plate structure is installed in the battery housing opening, a stopper 600 is required. That is, a stopper 600 is provided on the side of the top cover plate 100 away from the pole 200. As shown in FIG6 , the stopper 600 is provided with a welding hole 601 in conjunction with the electrode lead-out hole 101.

[0050] When assembling the cover structure, the cell connecting piece 700 needs to be electrically connected to the electrode 200. During this process, it is often difficult to accurately position the cell connecting piece 700, making the assembly process difficult. To this end, in one possible embodiment, as shown in Figures 6-9, a connecting piece 700 is further provided on the side of the stop frame 600 facing away from the top cover 100. The connecting piece 700 is provided with a raised positioning portion 701 that passes through the welding hole 601 and the electrode lead-out hole 101. The raised positioning portion 701 is connected to the electrode 200, thereby achieving the effect of quickly positioning the connecting piece 700 during installation.

[0051] In a further improvement to this embodiment, a positioning post 602 is provided on the 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 post 602. This can further achieve fast and accurate positioning and installation of the connecting piece 700 and prevent the connecting piece 700 from deflecting.

[0052] Example 2

[0053] This embodiment provides a secondary battery, which is mainly used in new energy power battery modules. Multiple secondary batteries can form a large power battery module to provide power for new energy vehicles and other equipment.

[0054] The secondary battery comprises a shell with at least one end open, a battery cell is arranged in the shell, the lithium battery cover structure in Example 1 is arranged at the shell opening, and the battery cell draws out electricity through a connecting piece 700 at the end.

[0055] In the description of the present invention, it should be noted that the directions or positional relationships indicated by the terms "front", "back", "left", "right", "up", "down", "top", "bottom", "inside" and "outside" are based on the directions or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, they cannot be understood as limitations on the present invention.

[0056] In the description of this utility model, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; mechanical connections, electrical connections; direct connections, indirect connections through an intermediate medium, and internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in this utility model based on the specific circumstances.

[0057] The scope of protection of the present invention is limited solely by the claims. Thanks to the teachings of the present invention, those skilled in the art will readily recognize that alternative structures to the structures disclosed in the present invention may be used as viable alternative embodiments, and that the embodiments disclosed in the present invention may 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 structure according to claim 1, characterized in that: 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 structure according to claim 1, wherein: 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 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 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 structure according to claim 1, wherein: The fixing part (400) is an insulating injection molded part.

7. The lithium battery cover structure according to any one of claims 1 to 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 lithium battery cover structure 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 lithium battery cover structure according to claim 7, characterized in that: 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 shell with at least one end open, wherein a battery cell is arranged in the shell, characterized in that: The lithium battery cover structure according to any one of claims 1 to 9 is provided at the shell opening, wherein the connecting piece (700) is electrically connected to the battery cell.

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