CN220672717U

CN220672717U - Battery cover plate structure and cylindrical lithium battery

Info

Publication number: CN220672717U
Application number: CN202322208997.7U
Authority: CN
Inventors: 文飞; 屈永辉; 肖泽强; 王诗龙; 李聪; 纪荣进; 齐东方; 郑明清
Original assignee: Zhejiang Lixin Energy Technology Co ltd
Current assignee: Zhejiang Lixin Energy Technology Co ltd
Priority date: 2023-08-17
Filing date: 2023-08-17
Publication date: 2024-03-26
Anticipated expiration: 2033-08-17

Abstract

The utility model discloses a battery cover plate structure and a cylindrical lithium battery, and belongs to the technical field of lithium batteries, wherein the cover plate structure comprises a main body piece, a pole column and a sealing piece, a connecting through hole is formed in the main body piece, a connecting groove is formed in the pole column, and the edge of the main body piece at the connecting through hole is penetrated in the connecting groove; the main body piece is provided with a sealing bulge, the connecting groove is internally provided with a sealing groove, the sealing bulge is arranged in the sealing groove, the sealing piece is arranged between the edge of the connecting through hole and the connecting groove and embedded between the sealing bulge and the sealing groove, and the sealing bulge is used for insulation and separating the main body piece from the pole. The cylindrical lithium battery comprises the cover plate structure. The utility model can improve the insulation reliability between the electrodes of the cylindrical lithium battery led out from the same end of the anode and the cathode, and reduce the probability of short circuit failure of the battery, thereby improving the safety of the battery.

Description

Battery cover plate structure and cylindrical lithium battery

Technical Field

The utility model relates to the technical field of lithium batteries, in particular to a battery cover plate structure and a cylindrical lithium battery.

Background

The cylindrical battery is an important structural form of the lithium battery, and mainly comprises a battery core, a shell and a cover plate, wherein a pole is arranged on the cover plate and is connected with a pole lug of the battery core through structures such as a bus plate. The cylindrical battery has the advantages of high energy density, good safety, wide application range and the like, and is widely favored by consumers and manufacturers.

The existing cylindrical battery is mainly provided with positive and negative electrodes at two ends of a cylindrical shell respectively, but in order to adapt to some specific application scenes, a structure is also provided that the positive and negative electrodes are arranged at the same end of the cylindrical shell.

For example, chinese patent document with application publication number CN115377480a discloses a novel cylindrical lithium battery structure, which comprises a housing, an electrode assembly, the center of the electrode assembly is a central hole, positive electrode multipolar lugs and negative electrode multipolar lugs are led out from the upper portion of the electrode assembly, the positive electrode multipolar lugs and the negative electrode multipolar lugs are distributed on opposite sides of the central hole and symmetrically distributed, an end cover is arranged above the electrode assembly, the end cover comprises a main body, a pole column, an insulating member and a sealing member, the center of the main body is provided with a through hole, the insulating member wraps the outer circumferential surface of the pole column, the pole column is positioned in the through hole, the insulating member seals the gap between the pole column and the end cover, the sealing member seals the upper edge of the main body and the housing, the negative electrode multipolar lugs are electrically connected with the main body, and the positive electrode multipolar lugs are electrically connected with the pole column. The novel cylindrical lithium battery structure adopts a structural form that the anode and the cathode are led out from the same end of the shell.

However, for a lithium battery including the positive and negative electrodes drawn out at the same end as described in the above patent document, there are general drawbacks as follows: the positive and negative lugs of the cylindrical lithium battery cell are arranged at the same end of the cell and welded and fixed with the cell cover plate at the same end, so that the distance between the positive electrode and the negative electrode is too short, the insulation structure between the positive electrode and the negative electrode is easy to lose effect, the insulation reliability between the positive electrode and the negative electrode of the lithium battery in the form is often inferior to that of a cylindrical battery led out from the positive electrode and the negative electrode at the two ends, and the probability of occurrence of short circuit failure condition of the positive electrode and the negative electrode is larger, and the safety is poor.

In view of this, there is a need for improvement in the structure of a conventional cylindrical battery in which the positive and negative electrodes are led out at the same end.

Disclosure of Invention

Aiming at the defects of the prior art, the utility model provides a battery cover plate structure and a cylindrical lithium battery, which are used for improving the insulation reliability between the electrodes of the cylindrical lithium battery led out from the same ends of the anode and the cathode and reducing the probability of short circuit failure of the battery, thereby improving the safety of the battery.

The utility model discloses a battery cover plate structure, which comprises a main body part, a pole column and a sealing part, wherein a connecting through hole is formed in the main body part, a connecting groove is formed in the pole column, and the edge of the main body part at the connecting through hole is penetrated in the connecting groove; the main body piece is provided with a sealing bulge, the connecting groove is internally provided with a sealing groove, the sealing bulge is arranged in the sealing groove, the sealing piece is arranged between the edge of the connecting through hole and the connecting groove and embedded between the sealing bulge and the sealing groove, and the sealing bulge is used for insulation and separating the main body piece from the pole.

Preferably, the cross section of the sealing protrusion is a trapezoid structure, and the cross section of the sealing groove is a trapezoid structure.

Preferably, the main body member has a sheet structure, and the sealing protrusions are arranged on both side surfaces of the main body member, and the sealing protrusions have a ring structure and are arranged around the connecting through holes.

Preferably, the sealing groove is of annular structure and is arranged around the pole.

Preferably, a safety valve is provided on the body member.

The utility model discloses a cylindrical lithium battery, which comprises any cover plate structure, a battery cell and a shell, wherein the shell is provided with an opening, the battery cell is arranged in the shell, and the cover plate structure is arranged at the opening of the shell.

Preferably, the battery cell is of a columnar structure, the battery cell is provided with a positive electrode tab and a negative electrode tab, the positive electrode tab and the negative electrode tab are positioned at the same end of the battery cell, the positive electrode tab is connected to the electrode post, and the negative electrode tab is connected to the main body piece.

Preferably, the housing is provided with a mounting groove, the main body member of the cover plate structure is inserted into the mounting groove, an insulating member is arranged between the main body member and the mounting groove, and the insulating member is used for insulating and separating the main body member and the housing.

Preferably, a sealing groove is arranged on the shell.

Preferably, the main body of the cover plate structure is provided with a lap joint part, and the lap joint part is connected with the edge of the opening of the shell.

The utility model has the beneficial effects that:

by arranging the structure that the sealing bulge is matched with the sealing groove in the cylindrical battery and arranging the sealing piece serving as an insulating material between the main body piece and the pole post, the positive pole lug and the negative pole lug of the battery cell positioned at the same end can be respectively welded on the pole post and the main body piece, the probability of short circuit between the main body piece and the pole post can be greatly reduced, and the risks of leakage and liquid leakage of the battery cell are reduced; therefore, the battery cover plate structure improves the insulation reliability between the cylindrical lithium battery electrodes led out from the same ends of the anode and the cathode, and reduces the probability of short circuit failure of the battery, thereby improving the safety of the battery.

Drawings

The accompanying drawings, which are included to provide a further understanding of the application and are incorporated in and constitute a part of this application, illustrate embodiments of the application and together with the description serve to explain the application and do not constitute an undue limitation to the application. In the drawings:

FIG. 1 is a schematic view of a cover plate structure of the present utility model;

FIG. 2 is a schematic structural view of the body member;

fig. 3 is a schematic structural view of a lithium battery of example 1;

fig. 4 is a schematic view showing the structure of the opening of the lithium battery case of example 1;

fig. 5 is a schematic structural view of a lithium battery of example 2;

fig. 6 is a schematic structural diagram of the lithium battery of example 2.

Reference numerals illustrate: 1. a cover plate structure; 11. a body member; 110. a connecting through hole; 111. a sealing protrusion; 112. a safety valve; 113. a lap joint; 12. a pole; 121. a connecting groove; 122. sealing the groove; 13. a seal; 2. a lithium battery; 21. a battery cell; 211. a positive electrode tab; 212. a negative electrode tab; 22. a housing; 221. a mounting groove; 222. a sealing groove; 23. an insulating member.

Detailed Description

Various embodiments of the utility model are disclosed in the following drawings, in which details of the practice are set forth in the following description for the purpose of clarity. However, it should be understood that these practical details are not to be taken as limiting the utility model. That is, in some embodiments of the utility model, these practical details are unnecessary. Moreover, for the sake of simplicity of the drawing, some well-known and conventional structures and elements are shown in the drawings in a simplified schematic manner.

It should be noted that all directional indications such as up, down, left, right, front, and rear … … in the embodiments of the present utility model are merely used to explain the relative positional relationship, movement, etc. between the components in a particular posture such as that shown in the drawings, and if the particular posture is changed, the directional indication is changed accordingly.

In addition, the descriptions of the "first", "second", etc. in this application are for descriptive purposes only and are not intended to specifically indicate a sequential or a cis-position, nor are they intended to limit the utility model, but are merely intended to distinguish between components or operations described in the same technical term, and are not to be construed as indicating or implying a relative importance or implying that the number of technical features indicated is not necessarily limited. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include at least one such feature. In addition, the technical solutions of the embodiments may be combined with each other, but it is necessary to base that the technical solutions can be realized by those skilled in the art, and when the technical solutions are contradictory or cannot be realized, the combination of the technical solutions should be considered to be absent and not within the scope of protection claimed in the present utility model.

For a further understanding of the utility model, its features and advantages, reference is now made to the following examples, which are illustrated in the accompanying drawings in which:

referring to fig. 1 and 2, a battery cover plate structure disclosed in the utility model comprises a main body member 11, a pole 12 and a sealing member 13, wherein the main body member 11 is of a metal sheet structure, and a connecting through hole 110 is formed on the surface of the main body member 11 for mounting the pole 12; the pole 12 is of a cylindrical structure, the side wall of the pole 12 is provided with a connecting groove 121, the connecting groove 121 is a groove, and the connecting groove 121 surrounds the side wall of the pole 12 to form an annular structure; the pole 12 is penetrated in the connecting through hole 110 of the main body member 11, and the edge of the main body member 11 at the connecting through hole 110 is penetrated in the connecting groove 121 of the pole 12; for easy assembly, the pole 12 is provided in a vertically split structure, and the mounting and fixing in the connection through-hole 110 are achieved by riveting or laser welding.

Referring to fig. 1 and 2, the body member 11 is provided with sealing protrusions 111 uniformly on both side surfaces thereof located in the connection groove 121, each sealing protrusion 111 is of an annular structure, the sealing protrusions 111 are arranged around the outer side of the connection through hole 110, the sealing protrusions 111 are cut by taking a surface perpendicular to the surface of the body member 11 and passing through the center of the annular structure of the sealing protrusions 111 as a tangential plane, the cross section of the cut sealing protrusions 111 is of an isosceles trapezoid, and the bottom edge of the isosceles trapezoid of the cross section of the sealing protrusions 111 coincides with the surface of the body member 11.

Referring to fig. 1 and 2, a sealing groove 122 is formed in a connecting groove 121 of a pole 12, the sealing groove 122 is formed in a side wall of the connecting groove 121 corresponding to a sealing protrusion 111, the sealing groove 122 is an annular groove, the sealing groove 122 is arranged around an axis of the pole 12, the pole 12 is cut by taking a surface which is perpendicular to the surface of a main body piece 11 and passes through the center of the annular structure of the sealing groove 122 as a tangential surface, the cross section of the sealing groove 122 is an isosceles trapezoid, the isosceles trapezoid of the cross section of the sealing groove 122 is the same as the isosceles trapezoid of the cross section of the sealing protrusion 111, the width of the bottom surface of the sealing groove 122 is smaller than the width of the opening of the sealing groove 122, and the sealing protrusion 111 of the main body piece 11 is embedded in the sealing groove 122 of the pole 12.

Referring to fig. 1 and 2, the sealing member 13 is disposed between the edge of the connection through-hole 110 and the connection groove 121, the sealing member 13 is made of an insulating material, the sealing member 13 is entirely ring-shaped and disposed around the axis of the pole 12, and the sealing member 13 surrounds the edge of the connection through-hole 110, is embedded between the sealing protrusion 111 and the sealing groove 122; cutting the sealing element 13 by taking a surface which is perpendicular to the surface of the main body element 11 and passes through the center of the annular structure of the sealing element 13 as a tangential surface, wherein the cross section of the cut sealing element 13 is U-shaped, the edge of the main body element 11 at the connecting through hole 110 penetrates into the U-shaped groove of the sealing element 13 and then is inserted into the connecting groove 121 of the pole 12, and the edge of the sealing element 13 extends out of the connecting groove 121 of the pole 12 and covers the surfaces of the two sides of the main body element 11, so that the insulation effect between the main body element 11 and the pole 12 is improved; through setting up the structure that sealed protruding 111 cooperatees with seal groove 122 to set up insulating material's sealing member 13 between main part 11 and utmost point post 12, the battery is located anodal utmost point ear 211 and the negative pole ear 212 of same one end and can weld respectively on utmost point post 12 and main part 11, can greatly reduce the probability that takes place the short circuit between main part 11 and the utmost point post 12, and reduce the risk that electric core 21 takes place gas leakage, weeping.

Referring to fig. 1 and 2, the surface of the main body 11 is provided with a safety valve 112, the safety valve 112 is an area with a thickness smaller than that of the main body 11, when a short circuit occurs in the battery and a large amount of gas is accumulated, the pressure in the battery is greatly increased, so that the safety valve 112 is broken, the pressure relief in the battery is realized, and the explosion of the battery is avoided.

The utility model also discloses a cylindrical lithium battery, referring to fig. 2-5, the lithium battery 2 comprises the battery cover plate structure 1, a battery core 21 and a shell 22, wherein the shell 22 is of a cylindrical structure with one end open, the battery core 21 is of a cylindrical structure, the battery core 21 is arranged in the shell 22, one end of the battery core 21, which faces the opening of the shell 22, is provided with a positive electrode tab 211 and a negative electrode tab 212, the battery cover plate structure 1 is arranged at the opening of the shell 22, the positive electrode tab 211 is connected with the electrode post 12 in a welding mode, and the negative electrode tab 212 is connected with the main body member 11 in a welding mode.

Example 1

Referring to fig. 3 and 4, in the lithium battery disclosed in this embodiment, an annular mounting groove 221 and an annular sealing groove 222 are formed at the edge of the opening of the case 22 by rolling, the mounting groove 221 and the sealing groove 222 are disposed around the circumference of the outer wall of the case 22, the opening of the mounting groove 221 faces the inside of the case 22, the opening of the sealing groove 222 faces the outside of the case 22, the mounting groove 221 is closer to the opening of the case 22 than the sealing groove 222, the cover plate structure 1 is mounted in the mounting groove 221, specifically, the outer peripheral edge of the body member 11 is inserted in the mounting groove 221, an insulating member 23 is disposed between the body member 11 and the mounting groove 221, the insulating member 23 is in an annular structure, the insulating member 23 is embedded in the mounting groove 221, and the insulating member 23 is used for realizing insulation between the body member 11 and the case 22, and only the body member 11 is used as the negative electrode of the battery at this time.

In the case of example 2,

referring to fig. 5 and 6, in the lithium battery disclosed in this embodiment, the outer peripheral edge of the main body member 11 is provided with a lap joint portion 113, the lap joint portion 113 is stepped, the lap joint portion 113 abuts against the edge of the opening of the case 22 and is in sealing connection with the case 22 by means of welding, at this time, the main body member 11 and the case 22 together serve as the negative electrode of the battery, and the battery can output the positive electrode and the negative electrode at the same end or output the positive electrode and the negative electrode at both ends respectively.

The implementation principle and the beneficial effects of the utility model are that by arranging the structure that the sealing protrusion 111 and the sealing groove 122 are mutually matched in the cylindrical battery and arranging the sealing piece 13 serving as an insulating material between the main body piece 11 and the pole post 12, the positive pole tab 211 and the negative pole tab 212 of the battery core 21 positioned at the same end can be respectively welded on the pole post 12 and the main body piece 11, the probability of short circuit between the main body piece 11 and the pole post 12 can be greatly reduced, and the risks of leakage and leakage of the battery core 21 are reduced; therefore, the battery cover plate structure 1 improves the insulation reliability between the electrodes of the cylindrical lithium battery 2 led out from the same end of the anode and the cathode, and reduces the probability of short circuit failure of the battery, thereby improving the safety of the battery.

The above is merely an embodiment of the present utility model, and is not intended to limit the present utility model. Various modifications and variations of the present utility model will be apparent to those skilled in the art. Any modification, equivalent replacement, improvement, or the like, which is within the spirit and principles of the present utility model, should be included in the scope of the claims of the present utility model.

Claims

1. The battery cover plate structure is characterized in that the cover plate structure (1) comprises a main body part (11), a pole column (12) and a sealing part (13), wherein a connecting through hole (110) is formed in the main body part (11), a connecting groove (121) is formed in the pole column (12), and the edge of the main body part (11) at the connecting through hole (110) is penetrated in the connecting groove (121);

the novel high-voltage power supply is characterized in that a sealing protrusion (111) is arranged on the main body piece (11), a sealing groove (122) is arranged in the connecting groove (121), the sealing protrusion (111) is arranged in the sealing groove (122), and the sealing piece (13) is arranged between the edge of the connecting through hole (110) and the connecting groove (121) and embedded between the sealing protrusion (111) and the sealing groove (122) and used for insulating and separating the main body piece (11) from the pole (12).

2. The battery cover plate structure according to claim 1, wherein the cross section of the sealing protrusion (111) is a trapezoid structure, and the cross section of the sealing groove (122) is a trapezoid structure.

3. The battery cover plate structure according to claim 1, wherein the main body member (11) is of a sheet-like structure, the sealing protrusions (111) are provided on both side surfaces of the main body member (11), and the sealing protrusions (111) are of a ring-like structure and are provided around the connection through holes (110).

4. The battery cover structure according to claim 1, characterized in that the sealing groove (122) is of annular structure and is arranged around the pole (12).

5. Battery cover structure according to any of claims 1-4, characterized in that the body part (11) is provided with a safety valve (112).

6. A cylindrical lithium battery, characterized in that the lithium battery (2) comprises the cover plate structure (1) according to any one of claims 1-5, and further comprises an electric core (21) and a shell (22), wherein the shell (22) is provided with an opening, the electric core (21) is installed in the shell (22), and the cover plate structure (1) is installed at the opening of the shell (22).

7. The cylindrical lithium battery according to claim 6, wherein the battery cell (21) has a columnar structure, the battery cell (21) has a positive electrode tab (211) and a negative electrode tab (212), the positive electrode tab (211) and the negative electrode tab (212) are located at the same end of the battery cell (21), the positive electrode tab (211) is connected to the electrode post (12), and the negative electrode tab (212) is connected to the main body member (11).

8. The cylindrical lithium battery according to claim 6, wherein a mounting groove (221) is formed in the housing (22), the main body member (11) of the cover plate structure (1) is inserted into the mounting groove (221), an insulating member (23) is disposed between the main body member (11) and the mounting groove (221), and the insulating member (23) is used for insulating and separating the main body member (11) and the housing (22).

9. The cylindrical lithium battery according to claim 8, wherein the case (22) is provided with a seal groove (222).

10. Cylindrical lithium battery according to claim 6, characterized in that the main body part (11) of the cover structure (1) is provided with a lap joint (113), which lap joint (113) is connected to the edge of the opening of the housing (22).