CN217955984U

CN217955984U - Button type lithium ion battery shell

Info

Publication number: CN217955984U
Application number: CN202221597114.5U
Authority: CN
Inventors: 罗国纲; 陈俊涛; 冯启枢; 闵幸福; 郭建伟
Original assignee: Apower Electronics Co ltd
Current assignee: Apower Electronics Co ltd
Priority date: 2022-06-23
Filing date: 2022-06-23
Publication date: 2022-12-02
Anticipated expiration: 2032-06-23

Abstract

The utility model relates to the technical field of batteries, a knot formula lithium ion battery shell is disclosed, which comprises an outer shell, first lid and second lid, the shell body is the hollow columnar structure that both ends set up for the opening, roll up the core and set up in the shell body, first lid sets up in the one end of shell body, the second lid sets up in the other end of shell body, the second lid includes first apron and second apron, first apron is connected with the shell body, be provided with the through-hole on the first apron, the one end that the shell body was kept away from to first apron is equipped with sunken connecting portion towards in the shell body is concave, the second apron sets up in sunken connecting portion. The button type lithium ion battery shell can improve the battery capacity of the lithium ion battery so as to prolong the battery endurance.

Description

Button type lithium ion battery shell

Technical Field

The utility model relates to the technical field of batteries, especially, relate to a knot formula lithium ion battery shell.

Background

At present, a steel shell button type lithium ion battery is generally sealed by plastics, a sealing part is sealed by welding a positive shell and a negative cover body through an ultrasonic welding process, and the material of a positive insulation part and a positive polarity center column are arranged at the center position of a central angle of a negative cover plate and are insulated from the negative polarity, so that the charging and discharging and performance testing of the battery are realized.

Because positive pole insulating part material and anodal polarity center post are through the integrative stamping forming of the mode of riveting rivet structure, the total thickness of final shaping is thicker, and the battery is whole highly need to reserve part for anodal insulating part material and anodal polarity center post, leads to the holistic built-in pole piece width of battery to reduce, and battery capacity reduces, and the inner space size of button lithium ion battery shell can't obtain more effective utilization to directly influence the whole energy density of battery and the duration of battery.

Therefore, it is desirable to design a new button-type lithium ion battery case to improve the above problems.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a knot formula lithium ion battery shell can improve lithium ion battery's battery capacity in order to prolong battery duration.

To achieve the purpose, the utility model adopts the following technical proposal:

a button lithium ion battery can comprising:

the outer shell is of a hollow columnar structure with openings at two ends, and the winding core is arranged in the outer shell;

the first cover body is arranged at one end of the outer shell;

the second cover body is arranged at the other end of the outer shell and comprises a first cover plate and a second cover plate, the first cover plate is connected with the outer shell, a through hole is formed in the first cover plate, one end, far away from the outer shell, of the first cover plate faces the concave connection portion formed in the outer shell, and the second cover plate is arranged in the concave connection portion.

Preferably, the surface of the second cover plate is convexly provided with a convex connecting part embedded in the through hole.

Preferably, the second cover plate and the protruding connecting part are respectively flush with two ends of the first cover plate.

Preferably, an insulating layer is arranged between the first cover plate and the second cover plate, the protruding connecting portion is connected with the positive electrode connecting portion of the winding core, and the first cover body is connected with the negative electrode connecting portion of the winding core.

Preferably, the thickness of the insulating layer is 0.05mm to 0.15mm.

Preferably, the sum of the thicknesses of the first cover plate, the insulating layer and the second cover plate is less than 0.4mm.

Preferably, the end surface of the first cover body facing the outer shell is provided with a pressure relief groove.

Preferably, the depth of the pressure relief groove is 35% to 85% of the thickness of the first cover body.

Preferably, the first lid has an injection port on an end surface thereof.

Preferably, the outer housing and the first cover are integrally formed.

The utility model has the advantages that: the utility model provides a pair of knot formula lithium ion battery shell, be two parts with the second lid split, first apron is connected with the shell body, the concave sunken connecting portion of establishing the formation of first apron can supply the second apron to locate wherein just, sunken connecting portion can carry on spacingly to the position of placing of second apron on the one hand, ensure that the second apron can shield the through-hole, can utilize the sunk space to make the whole thickness of second lid keep thinner on the other hand, with this save knot formula lithium ion battery shell's inner space, thereby improve lithium ion battery's battery capacity and in order to prolong the duration of battery. The first cover plate and the recessed connection portion can be attached to the end face and the inner wall of the outer shell, the contact surface of the first cover plate and the outer shell is increased, and the connection sealing performance is higher.

Additional aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.

Drawings

Fig. 1 is a schematic cross-sectional structure diagram of a button-type lithium ion battery case according to an embodiment of the present invention;

fig. 2 is a schematic top view of a button-type lithium ion battery case according to an embodiment of the present invention;

fig. 3 is a schematic structural diagram of a first cover plate according to an embodiment of the present invention;

fig. 4 is a schematic cross-sectional structure diagram of a button-type lithium ion battery case provided in the second embodiment of the present invention;

fig. 5 is a schematic cross-sectional structure diagram of a button lithium ion battery case provided by the third embodiment of the present invention.

In the figure:

10. an outer housing;

20. a first cover body; 21. a pressure relief groove; 22. a liquid injection port;

30. a second cover body; 31. a first cover plate; 311. a through hole; 312. a recessed connection portion; 32. a second cover plate; 321. a bump connecting portion;

40. an insulating layer.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings and examples. It is to be understood that the specific embodiments described herein are merely illustrative of the invention and are not limiting of the invention. It should be further noted that, for the convenience of description, only some of the structures related to the present invention are shown in the drawings, not all of the structures.

In the description of the present invention, unless expressly stated or limited otherwise, the terms "connected," "connected," and "fixed" are to be construed broadly, e.g., as meaning permanently connected, detachably connected, or integral to one another; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or may be connected through the use of two elements or the interaction of two elements. The specific meaning of the above terms in the present invention can be understood in specific cases to those skilled in the art.

In the present disclosure, unless expressly stated or limited otherwise, the first feature "on" or "under" the second feature may comprise direct contact between the first and second features, or may comprise contact between the first and second features not directly. Also, the first feature being "on," "above" and "over" the second feature includes the first feature being directly on and obliquely above the second feature, or merely indicating that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature includes the first feature being directly under and obliquely below the second feature, or simply meaning that the first feature is at a lesser elevation than the second feature.

In the description of the present embodiment, the terms "upper", "lower", "right", etc. are used in an orientation or positional relationship based on that shown in the drawings only for convenience of description and simplicity of operation, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first" and "second" are used only for descriptive purposes and are not intended to have a special meaning.

Example one

Referring to fig. 1 to 3, the present embodiment provides a button-type lithium ion battery case including an outer case 10, a first cover 20, and a second cover 30. The two ends of the outer shell 10 are open and are integrally of a hollow cylindrical structure, the winding core formed by winding is placed in the outer shell 10 from one end of the outer shell 10, the first cover body 20 is arranged at one end of the outer shell 10, and the second cover body 30 is arranged at the other end of the outer shell 10, so that the outer shell 10 is closed.

Specifically, in this embodiment, the existing button-type lithium ion battery case composed of the positive electrode shell and the negative electrode cover is divided into three parts, namely, the outer case 10, the first cover 20 and the second cover 30, when the button-type lithium ion battery case is packaged, after the winding core is placed in the outer case 10, the first cover 20 is welded and fixed to the negative electrode connecting portion of the winding core, the second cover 30 is welded and fixed to the positive electrode connecting portion of the winding core, and then the first cover 20 and the second cover 30 are welded to the two ends of the outer case 10, so that the electrode connecting portion of the winding core can be visually welded to the first cover 20 and the second cover 30, the welding firmness is higher, and the manufacturability of the button-type lithium ion battery case package is improved.

The first cover body 20 and the second cover body 30 are welded and fixed at two ends of the outer shell 10 in sequence in a welding connection mode, all welding processes of the embodiment adopt laser welding, focused laser beams have high power density, the heating speed is high, and the possibility of welding stress and deformation is low, so that the method is suitable for welding of all parts of the shell of the button lithium ion battery.

Because in the prior art, the positive insulation position material and the positive polarity center post are formed by integral punch forming in a riveting rivet structure mode, the forming thickness is thick, the partial space of the button type lithium ion battery shell is occupied, the width of a roll core is reduced, the battery capacity is reduced, and the internal space size of the button type lithium ion battery shell cannot be effectively utilized.

In view of the above problem, as shown in fig. 1 and fig. 2, the second cover 30 includes a first cover plate 31 and a second cover plate 32, the first cover plate 31 is connected to one end of the outer housing 10, a through hole 311 is formed in a center of the first cover plate 31, a concave connecting portion 312 is concavely formed on one end of the first cover plate 31, which is far away from the outer housing 10, facing the outer housing 10, and the second cover plate 32 is disposed in the concave connecting portion 312.

It can be understood that, the second cover body 30 is split into two parts, the first cover plate 31 is connected with the outer shell 10, the recessed connection portion 312 formed by the recessed arrangement of the first cover plate 31 is just provided for the second cover plate 32 to be arranged therein, the recessed connection portion 312 can limit the placement position of the second cover plate 32 on one hand, and ensure that the second cover plate 32 can shield the through hole 311, and on the other hand, the recessed space can be utilized to keep the overall thickness of the second cover body 30 thinner, so as to save the internal space of the button lithium ion battery shell, thereby improving the battery capacity of the lithium ion battery and prolonging the cruising ability of the battery.

In other embodiments, the step surface formed by the recessed connection portion 312 on the end surface of the first cover plate 31 facing the outer casing 10 is attached to the end surface and the inner wall of the outer casing 10, so that the contact surface between the first cover plate 31 and the outer casing 10 is increased, the connection tightness between the two is higher, the occurrence of electrolyte leakage is reduced, and the use safety of the battery is improved.

As shown in fig. 1 and 2, an insulating layer 40 is disposed between the first cover plate 31 and the second cover plate 32, the insulating layer 40 is made of latex colloid, and the insulating layer 40 is formed by dipping, baking, drying or spraying, so that on one hand, the insulating layer 40 can bond and fix the first cover plate 31 and the second cover plate 32, on the other hand, the insulating layer can insulate the positive second cover plate 32 and the negative first cover plate 31, compared with a method of connecting a positive insulating material with a positive polarity center post by riveting rivets, the overall thickness of the insulating layer 40 is thin, and the insulating layer 40 is integrated in the thickness of the second cover 30 by the concave connecting portion 312, and does not occupy the inner space of the outer housing 10. Illustratively, the thickness of the insulating layer 40 is 0.05mm to 0.15mm.

Furthermore, the surface of the second cover plate 32 is convexly provided with a convex connecting part 321 embedded into the through hole 311, the second cover plate 32 and the convex connecting part 321 are respectively flush with two ends of the first cover plate 31, the second cover plate 32 is connected with the positive connecting part of the winding core, and end faces of two ends of the winding core are attached to the surfaces of the first cover plate 31 and the first cover body 20, so that the thickness of the outer shell 10 is ensured to be the width of the winding core, and the internal space of the shell of the button-type lithium ion battery is utilized to the maximum extent. Illustratively, the sum of the thicknesses of the first cover plate 31, the insulating layer 40 and the second cover plate 32 is less than 0.4mm.

As shown in fig. 3, in the present embodiment, a pressure relief groove 21 is opened on an end surface of the first cover 20 facing the outer housing 10, the pressure relief groove 21 is disposed in an "S" shape, a radius of the pressure relief groove 21 is 0.15 to 0.5mm, and a depth of the pressure relief groove 21 is 35% to 85%, preferably 50%, of a thickness of the first cover 20. The pressure relief groove 21 is arranged to release air pressure from the inside of the battery before the battery explodes when the battery expands after a short circuit occurs in the battery, so that the battery explosion is avoided. Of course, in other embodiments, the pressure relief groove 21 may also be in other shapes such as a circle, an ellipse, and a rectangle, and the shape of the pressure relief groove 21 is not limited in this embodiment.

As shown in fig. 3, a filling opening 22 is formed through the end surface of the first lid 20 in this embodiment, the filling opening 22 is used for filling the electrolyte into the outer case 10, a sealing nail is provided at the pole filling opening 22, and the filling opening 22 is blocked by the sealing nail to ensure the sealing performance at the filling opening 22 after the battery pack is completed.

Example two

The button lithium ion battery case provided in this embodiment is basically the same as the button lithium ion battery case of the first embodiment in structure, and the main difference between the two cases is as follows: as shown in fig. 4, in the present embodiment, the outer casing 10 and the first cover 20 are integrally formed to form the outer casing 10 with an opening at one end, and the first cover 20 is welded at the opening end of the outer casing 10. Roll up the core and put into shell body 10 from the open end of shell body 10 in, the negative pole connecting portion of rolling up the core pastes with first lid 20 mutually, and the anodal connecting portion of rolling up the core welds fixedly the back with second apron 32, compresses tightly first apron 31 and rolls up the core and weld in shell body 10 again to can save welding work portion, improve battery production efficiency.

EXAMPLE III

The button lithium ion battery case provided in this embodiment is basically the same as the button lithium ion battery case of the second embodiment in structure, and the main difference between the two cases is as follows: as shown in fig. 5, the peripheral side of the outer casing 10 of the present embodiment is provided with a mounting hole, and the first cover plate 31, the second cover plate 32 and the insulating layer 40 are disposed in the mounting hole of the outer casing 10 and configured into an arc shape adapted to the outer casing 10, so as to be adapted to various types of winding cores, thereby making batteries of different types and types to meet application requirements of various products.

It can be understood that, the roll core is put into the outer shell 10 from the open end of the outer shell 10, the negative electrode connecting part of the roll core is welded with the end face of the first cover body 20, and the positive electrode connecting part of the roll core is bent to the peripheral side of the roll core and is welded with the second cover plate 32 positioned on the peripheral side of the outer shell 10, that is, the welding can also keep the visualization of the detection welding spot, thereby ensuring the reliability of the welding.

It is obvious that the above embodiments of the present invention are only examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. Numerous obvious variations, rearrangements and substitutions will now occur to those skilled in the art without departing from the scope of the invention. And are neither required nor exhaustive of all embodiments. Any modification, equivalent replacement, and improvement made within the spirit and principle of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A button type lithium ion battery shell is characterized by comprising:

the winding core is arranged in the outer shell (10);

a first cover (20) disposed at one end of the outer case (10);

the second cover body (30) is arranged at the other end of the outer shell (10), the second cover body (30) comprises a first cover plate (31) and a second cover plate (32), the first cover plate (31) is connected with the outer shell (10), a through hole (311) is formed in the first cover plate (31), one end, far away from the outer shell (10), of the first cover plate (31) faces towards the outer shell (10) and is concavely provided with a sunken connecting portion (312), and the second cover plate (32) is arranged in the sunken connecting portion (312).

2. The button lithium ion battery shell according to claim 1, wherein the surface of the second cover plate (32) is convexly provided with a convex connection part (321) embedded in the through hole (311).

3. The button lithium ion battery case according to claim 2, wherein the second cover plate (32) and the protruding connection part (321) are flush with both ends of the first cover plate (31), respectively.

4. The button type lithium ion battery shell according to claim 3, characterized in that an insulating layer (40) is arranged between the first cover plate (31) and the second cover plate (32), the protruding connecting part (321) is connected with the positive connecting part of the winding core, and the first cover body (20) is connected with the negative connecting part of the winding core.

5. The button lithium ion battery case according to claim 4, wherein the thickness of the insulating layer (40) is 0.05mm to 0.15mm.

6. Button lithium ion battery cell casing according to claim 4, characterized in that the sum of the thickness of the first cover plate (31), the insulating layer (40) and the second cover plate (32) is less than 0.4mm.

7. The button type lithium ion battery shell according to claim 1, wherein a pressure relief groove (21) is formed on the end surface of the first cover body (20) facing the outer shell body (10).

8. The button lithium ion battery shell according to claim 7, wherein the depth of the pressure relief groove (21) is 35-85% of the thickness of the first cover body (20).

9. The button lithium ion battery shell according to claim 1, characterized in that the end face of the first cover body (20) is provided with a liquid injection port (22).

10. The button lithium ion battery shell according to claim 1, wherein the outer shell (10) and the first cover (20) are of an integral structure.