Cover plate assembly, battery case, and battery

Abstract

A cover plate assembly (12), a battery case (10a), and a battery (10). The cover plate assembly (12) comprises: a cover plate (121), which is provided with an electrode-column mounting hole (103) and a pressure relief hole (104), wherein the electrode-column mounting hole (103) is configured to accommodate an electrode column (10c) of a battery, and the pressure relief hole (104) is configured to accommodate a pressure relief valve (10d); and an insulating member (122), which is stacked with the cover plate (121), wherein the insulating member (122) is provided with a hole (105), a projection of the pressure relief hole (104) on the insulating member (122) at least partially overlaps with the hole (105), and the insulating member further comprises a thin film part (13), which is configured to block the hole.

Description

Cover plate assembly, battery shell and battery

[0001] This application claims priority to the Chinese patent application filed with the China Patent Office on December 27, 2023, with application number 202323601566.3. The entire contents of the above application are incorporated by reference into this application. Technical Field

[0002] The present application relates to the field of battery technology, and in particular to a cover assembly, a battery shell and a battery. Background Art

[0003] With the rapid development of new energy technologies, batteries have been widely used in various new energy vehicles and energy storage power stations. During the use of batteries, if short circuits, overcharges, etc. occur, a large amount of heat will accumulate inside the battery, resulting in thermal runaway. Thermal runaway will cause the internal pressure of the battery to be too high, causing fire or even explosion.

[0004] In the related art, a pressure relief valve is generally provided on the top cover of the battery shell. When the internal pressure of the battery is too high, the pressure relief valve is opened to release the internal pressure of the battery. In order to avoid short circuit caused by short circuit between the positive and negative poles of the battery, an insulating member is usually provided between the top cover and the battery core pack. Technical issues

[0005] In order to ensure that the internal pressure of the battery can open the pressure relief valve, a through hole needs to be set on the insulating part at the position corresponding to the pressure relief valve. This leads to the formation of an electron channel between the core package and the top cover due to the existence of this through hole, thereby causing corrosion to the top cover. Technical Solutions

[0006] In a first aspect, the present application provides a cover plate assembly, comprising: a cover plate, provided with a pole mounting hole and a pressure relief hole, the pole mounting hole being used to accommodate the pole of the battery, and the pressure relief hole being used to accommodate the pressure relief valve; an insulating member, stacked with the cover plate, the insulating member being provided with an opening, the projection of the pressure relief hole on the insulating member at least partially overlapping with the opening, and further comprising a film portion for sealing the opening.

[0007] In a second aspect, the present application provides a battery case, comprising a shell and a cover plate assembly, wherein the shell is formed with a receiving space and an opening connected to the receiving space, the cover plate is covered in the opening, and an insulating member is arranged on a side of the cover plate close to the receiving space.

[0008] In a third aspect, the present application provides a battery, comprising a core pack and a battery shell, wherein the core pack is disposed in a receiving space. Beneficial effects

[0009] The beneficial effects of the cover plate assembly, battery shell and battery provided in the present application are as follows: different from the related art, the cover plate assembly provided in the present application includes a cover plate, which is provided with a pole mounting hole and a pressure relief hole, the pole mounting hole is used to accommodate the pole of the battery, and the pressure relief hole is used to accommodate the pressure relief valve; an insulating member is stacked with the cover plate, the insulating member is provided with an opening, the projection of the pressure relief hole on the insulating member and the opening at least partially overlap, and also includes a film portion for sealing the opening, so that when the core package has thermal runaway, the internal high pressure or high temperature of the shell can flush or melt the film portion, thereby flushing the pressure relief valve and releasing the internal pressure of the shell. Through this arrangement, without affecting the safe pressure relief of the battery, the electron channel generated between the core package and the cover plate is blocked by the film portion, thereby avoiding the corrosion of the cover plate caused by the electron channel and improving the safety of the battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] FIG1 is a schematic diagram of the three-dimensional structure of a battery embodiment provided by the present application;

[0011] FIG2 is a schematic cross-sectional view of the battery in FIG1 with the FF direction upward;

[0012] FIG3 is a schematic cross-sectional view of the housing in FIG2 ;

[0013] FIG4 is a schematic diagram of the exploded structure of the cover plate assembly in FIG1 ;

[0014] FIG5 is an enlarged schematic diagram of an embodiment of the portion M in FIG2 ;

[0015] FIG6 is an enlarged schematic diagram of another embodiment of the portion M in FIG2 ;

[0016] FIG7 is an enlarged schematic diagram of another embodiment of the M portion in FIG2 ;

[0017] FIG8 is a schematic three-dimensional structural diagram of another embodiment of the film portion in FIG5 . Modes for Carrying Out the Invention

[0018] Please refer to Figures 1 and 2 together. Figure 1 is a three-dimensional structural schematic diagram of an embodiment of a battery 10 provided in this application, and Figure 2 is a cross-sectional schematic diagram of the battery 10 in Figure 1 with the FF upward. The battery 10 in this embodiment includes a battery shell 10a and a core pack 10b.

[0019] Please refer to Figures 2 and 3 together. Figure 3 is a cross-sectional schematic diagram of the shell 11 in Figure 2. The battery shell 10a includes a shell 11 and a cover assembly 12. The shell 11 is formed with a receiving space 101 and an opening 102. The opening 102 is connected to the receiving space 101. The core pack 10b is arranged in the receiving space 101. In actual applications, the shell 11 is generally made of aluminum.

[0020] Please refer to Figures 1 and 4 together. Figure 4 is a schematic diagram of the three-dimensional decomposition structure of the cover assembly 12 in Figure 1. The cover assembly 12 includes a cover 121 and an insulating member 122. The cover 121 covers the opening 102. The cover 121 is provided with a pole mounting hole 103 and a pressure relief hole 104. The pole mounting hole 103 is used to accommodate the pole 10c of the battery 10. It can be understood that in actual applications, the number of pole mounting holes 103 is two, which respectively accommodate the positive pole and the negative pole of the battery 10. The pressure relief hole 104 is used to accommodate the pressure relief valve 10d, so that when the core package 10b has a thermal runaway phenomenon, the pressure relief valve 10d is opened, thereby releasing the internal pressure of the shell 11 to avoid fire or even explosion.

[0021] In one embodiment, the insulating member 122 is disposed on a side of the cover plate 121 close to the receiving space 101 and is stacked with the cover plate 121 .

[0022] The insulating member 122 is provided with an opening 105 , and the projection of the pressure relief hole 104 on the insulating member 122 at least partially overlaps with the opening 105 .

[0023] Please refer to Figures 5, 6 and 7 together. Figure 5 is an enlarged schematic diagram of one embodiment of the M part in Figure 2, Figure 6 is an enlarged schematic diagram of another embodiment of the M part in Figure 2, and Figure 7 is an enlarged schematic diagram of yet another embodiment of the M part in Figure 2. The cover plate assembly 10 in this embodiment also includes a film portion 13 for sealing the opening 105, so that when the core package 10b has a thermal runaway phenomenon, the internal high pressure or high temperature of the shell 11 can flush or melt the film portion 13, thereby flushing the pressure relief valve 10d and releasing the internal pressure of the shell 11. Through this arrangement, without affecting the safe pressure relief of the battery 10, the electron channel generated between the core package 10b and the cover plate 121 is blocked by the film portion 13, thereby avoiding corrosion of the cover plate 121 caused by the electron channel, thereby improving the safety of the battery 10.

[0024] In this embodiment, the thickness of the thin film portion 13 is 0.02 mm to 0.3 mm.

[0025] In one embodiment as shown in FIG5 , the opening 105 passes through the insulating member 122 , and the film portion 13 is connected to the insulating member 122 and covers the opening 105 . In specific applications, the film portion 13 and the insulating member 122 may be connected by gluing, welding or other methods, which are not limited thereto.

[0026] In one embodiment, the opening 105 includes a first hole segment 1051 and a second hole segment 1052, the aperture of the first hole segment 1051 is larger than the aperture of the second hole segment 1052, and the film portion 13 is arranged in the first hole segment 1051 and covers the second hole segment 1052. In this way, the film portion 13 does not occupy the space between the cover plate 121 and the insulating member 122, thereby improving the volume energy density of the core package 10b.

[0027] In one embodiment, in the thickness direction of the insulating member 122, that is, in the direction A as shown in Figure 5, the surface formed by the center point of the side wall of the opening 105 is defined as the center plane I, and the distance between the film portion 13 and the cover plate 121 is greater than the distance between the center plane I and the cover plate 121. It can be understood that the center plane I is a virtual surface artificially defined for the convenience of explanation.

[0028] In another embodiment as shown in Figure 6, the opening 105 passes through the insulating member 122, and the film portion 13 is connected to the cover plate 121 and covers the opening 105. In specific applications, the film portion 13 and the cover plate 121 can be connected by gluing, welding or other methods, which are not limited to this. It can be understood that the film portion 13 can also be connected to the cover plate 121 and the insulating member 122 at the same time, which will not be repeated here.

[0029] In another embodiment as shown in Figure 7, the insulating member 122 includes an insulating body 122a and a thin film portion 13, the thin film portion 13 is connected to the insulating body 122a and the thickness of the thin film portion 13 is less than the thickness of the insulating body 122a, and the insulating body 122a and the thin film portion 13 are integrally formed. In actual applications, the insulating member 122 can be formed into the insulating body 122a and the thin film portion 13 by integral injection molding.

[0030] Please refer to Figure 8, which is a three-dimensional structural schematic diagram of another embodiment of the film portion 13 in Figure 5. In this other embodiment, the film portion 13 is provided with a film gap 13a, so that the film portion 13 forms a plurality of spliced ​​film petals 131. Through this arrangement, the structural strength of the film portion 13 is reduced, thereby reducing the resistance of the internal pressure of the shell 11 to the film portion 13 being opened.

[0031] In one embodiment, the membrane petal 131 is an elastic membrane petal. The elastic membrane petal 131 can make multiple membrane petals 131 squeeze each other, avoiding the formation of an electron channel between the core package 10b and the cover plate 121 due to the existence of the film gap 13a when there is no thermal runaway phenomenon in the core package 10b.

[0032] Different from the related art, the cover plate assembly provided in the embodiment of the present application includes: a cover plate, which is provided with a pole mounting hole and a pressure relief hole, the pole mounting hole is used to accommodate the pole of the battery, and the pressure relief hole is used to accommodate the pressure relief valve; an insulating member, which is stacked with the cover plate, and the insulating member is provided with an opening, and the projection of the pressure relief hole on the insulating member at least partially overlaps with the opening, and also includes a film portion for sealing the opening, so that when the core package has thermal runaway, the internal high pressure or high temperature of the shell can flush or melt the film portion, thereby flushing the pressure relief valve and releasing the internal pressure of the shell. Through this arrangement, the electron channel generated between the core package and the cover plate is blocked by the film portion without affecting the safe pressure relief of the battery, thereby avoiding corrosion of the cover plate caused by the electron channel and improving the safety of the battery.

Claims

1. A cover plate assembly, comprising: The cover plate is provided with a pole mounting hole and a pressure relief hole, wherein the pole mounting hole is used to accommodate the pole of the battery, and the pressure relief hole is used to accommodate the pressure relief valve; An insulating member is stacked with the cover plate, the insulating member is provided with an opening, the projection of the pressure relief hole on the insulating member at least partially overlaps with the opening, and also includes a film portion for blocking the opening.

2. The cover plate assembly according to claim 1, wherein: The opening passes through the insulating member, and the film portion is connected to the cover plate and / or the insulating member and covers the opening.

3. The cover plate assembly according to claim 2, wherein: The opening includes a first hole segment and a second hole segment. The hole diameter of the first hole segment is larger than the hole diameter of the second hole segment. The film portion is disposed in the first hole segment and covers the second hole segment.

4. The cover plate assembly according to claim 1, wherein: The insulating member includes an insulating body and the thin film portion, the thin film portion is connected to the insulating body and the thickness of the thin film portion is smaller than the thickness of the insulating body, and the insulating body and the thin film portion are integrally formed.

5. The cover plate assembly according to claim 2, wherein: The film portion is connected to the insulating member, and in the thickness direction of the insulating member, a plane formed by the center point of the side wall of the opening is defined as a center plane, and a distance between the film portion and the cover plate is greater than a distance between the center plane and the cover plate.

6. The cover plate assembly according to any one of claims 1 to 5, wherein: The film portion is provided with a film gap so that the film portion forms a plurality of film petals which are spliced ​​and arranged.

7. The cover plate assembly according to claim 6, wherein: The membrane flap is an elastic membrane flap.

8. The cover plate assembly according to any one of claims 1 to 5, wherein: The thickness of the film portion is 0.02 mm to 0.3 mm.

9. A battery shell, comprising a shell and a cover plate assembly according to any one of claims 1 to 8, wherein the shell is formed with a receiving space and an opening connected to the receiving space, the cover plate is covered on the opening, and the insulating member is arranged on a side of the cover plate close to the receiving space.

10. A battery, comprising a core pack and the battery shell according to claim 9, wherein the core pack is arranged in the accommodating space.

Images