US-12626998-B2 - End cover assembly, battery, and electric device

US12626998B2US 12626998 B2US12626998 B2US 12626998B2US-12626998-B2

Abstract

An end cover assembly, a battery, and an electric device are provided. The end cover assembly is applied to a battery and includes an end cover, a breather valve, and a protective patch. The end cover has a first side facing inside of the battery and a second side opposite the first side and includes a first channel in communication with the first side and the second side. The breather valve includes a gas-permeable membrane in gas communication with the first channel. The gas-permeable membrane includes a gas-permeable portion opened towards the second side of the end cover. The protective patch is provided on the second side of the end cover and covers the gas-permeable portion. The battery includes the end cover assembly. The electric device includes the battery.

Inventors

Liqin Wang
Quankun Li

Assignees

CONTEMPORARY AMPEREX TECHNOLOGY CO., LIMITED

Dates

Publication Date: 20260512
Application Date: 20240819

Claims (13)

1 . An end cover assembly, applied to a battery and comprising: an end cover, having a first side facing inside of the battery and a second side opposite the first side and comprising a first channel in communication with the first side and the second side; a breather valve, comprising a gas-permeable membrane in gas communication with the first channel, wherein the gas-permeable membrane comprises a gas-permeable portion opened towards the second side of the end cover; and a protective patch, provided on the second side of the end cover and covering the gas-permeable portion, wherein a second channel in gas communication with the gas-permeable membrane is provided between the protective patch and the end cover; wherein the end cover comprises a breather valve mounting groove; the breather valve is located in the breather valve mounting groove; the first channel is provided in a bottom wall of the breather valve mounting groove; and the second channel is in communication with the breather valve mounting groove; wherein an opening of the breather valve mounting groove is provided in the first side of the end cover, or the opening of the breather valve mounting groove is provided in the second side of the end cover.
2 . The end cover assembly according to claim 1 , wherein the breather valve further comprises a valve plate; the valve plate is mounted on the end cover and comprises a third channel running through two side surfaces of the valve plate; and the gas-permeable membrane is fixed to the valve plate and covers the third channel; wherein the breather valve mounting groove is a stepped groove, the stepped groove comprising: a first groove section close to the bottom wall of the breather valve mounting groove, wherein the gas-permeable membrane is located in the first groove section and has a gap with the bottom wall; and a second groove section connected to the first groove section, with a step surface formed at a joint, wherein the valve plate is located in the second groove section and abuts against the step surface.
3 . The end cover assembly according to claim 2 , wherein a height of the first groove section is 0.1 mm to 0.5 mm greater than a thickness of the gas-permeable membrane; and/or a height of the second groove section is equal to a thickness of the valve plate or is no more than 0.5 mm greater than the thickness of the valve plate.
4 . The end cover assembly according to claim 1 , wherein the end cover comprises an end cover body, the breather valve mounting groove being disposed on the end cover body; wherein the end cover further comprises: a lug boss provided on the end cover body and protruding towards the second side of the end cover, wherein the second channel comprises a communication groove or communication hole provided in the lug boss; and/or a ventilation groove, wherein the ventilation groove is provided in the end cover body, located on the second side of the end cover and in communication with the breather valve mounting groove; and the second channel comprises the ventilation groove.
5 . The end cover assembly according to claim 4 , wherein the lug boss has a height of 0.1 mm to 0.5 mm; and/or the lug boss is located on an outer side of the breather valve mounting groove, and a distance from an edge of the lug boss close to the breather valve mounting groove to an edge of the breather valve mounting groove is 0.5 mm to 3 mm.
6 . The end cover assembly according to claim 4 , wherein the ventilation groove has a depth of 0.05 mm to 0.3 mm; and/or a distance from an edge of the ventilation groove located on an outer side of the protective patch to an edge of the protective patch is 0.1 mm to 0.5 mm.
7 . The end cover assembly according to claim 1 , wherein the protective patch comprises a patch body covering the gas-permeable portion and a fixing adhesive layer, wherein the fixing adhesive layer is provided on a side of the patch body facing the end cover, and the patch body is adhered to the second side of the end cover by virtue of the fixing adhesive layer.
8 . The end cover assembly according to claim 7 , wherein the fixing adhesive layer is attached to a partial region of the patch body, wherein a region, with no fixing adhesive layer attached, of the patch body is transparent; and/or the region, with the fixing adhesive layer attached, of the patch body and/or the fixing adhesive layer is colored.
9 . The end cover assembly according to claim 7 , wherein the fixing adhesive layer is located at an edge of the patch body; and/or the fixing adhesive layer is kept away from the second channel.
10 . The end cover assembly according to claim 1 , wherein the protective patch comprises a patch body covering the gas-permeable portion, wherein the patch body is made of polyethylene glycol terephthalate; and/or the patch body has a thickness of 0.1 mm to 0.2 mm.
11 . The end cover assembly according to claim 1 , wherein the end cover comprises a patch mounting groove, and the protective patch is located in the patch mounting groove.
12 . A battery, wherein the battery comprises the end cover assembly according to claim 1 .
13 . An electric device, wherein the electric device comprises the battery according to claim 12 , and the battery is configured to provide electric power for the electric device.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This application is a continuation application of PCT Patent Application No. PCT/CN2022/088766, entitled “END COVER ASSEMBLY, BATTERY, AND ELECTRIC DEVICE” filed on Apr. 24, 2022, the content of which is incorporated herein by reference in its entirety. TECHNICAL FIELD This disclosure relates to the field of battery technologies, and in particular, to an end cover assembly, a battery, and an electric device. BACKGROUND In the related art, a breather valve can be provided on an end cover assembly of a battery cell to balance internal and external pressure of the battery cell so as to protect internal components. Under the action of a pressure difference, gas inside and outside the battery cell passes through a gas-permeable membrane via a gas channel of the breather valve for gas compensation to maintain internal and external gas pressure balance for the battery cell. In the process of implementing this disclosure, the inventor has found that: in an assembly process of the battery cell, foreign substances such as welding slag produced in a welding process and spray liquid produced in an electrolyte injection process contaminate the breather valve, thus affecting the gas permeation effect. SUMMARY This disclosure provides an end cover assembly, a battery, and an electric device to protect a breather valve and improve the gas permeation effect of the breather valve. According to a first aspect, this disclosure provides an end cover assembly. The end cover assembly is applied to a battery and includes an end cover, a breather valve, and a protective patch. The end cover has a first side facing inside of the battery and a second side opposite the first side and includes a first channel in communication with the first side and the second side. The breather valve includes a gas-permeable membrane in gas communication with the first channel. The gas-permeable membrane includes a gas-permeable portion opened towards the second side of the end cover. The protective patch is provided on the second side of the end cover and covers the gas-permeable portion. According to the end cover assembly of this disclosure, due to the provision of the protective patch, the protective patch covers the gas-permeable portion of the gas-permeable membrane facing the second side of the end cover, helping to prevent welding slag or an electrolyte from polluting the gas-permeable membrane. Therefore, the gas-permeable membrane of the breather valve in the end cover assembly can be protected by the protective patch, the gas permeation effect of the breather valve is improved, and thus the breather valve can better balance internal and external pressure of a battery cell to achieve the function of protecting internal components. In an end cover assembly according to some embodiments, a second channel in gas communication with the gas-permeable membrane is provided between the protective patch and the end cover. Since the second channel in gas communication with the gas-permeable membrane is provided between the protective patch and the end cover, the second channel enables gas passing through the gas-permeable membrane of the breather valve to smoothly enter or get out of the battery cell. In an end cover assembly according to some embodiments, the end cover includes a breather valve mounting groove; the breather valve is located in the breather valve mounting groove; the first channel is provided in a bottom wall of the breather valve mounting groove, and the second channel is in communication with the breather valve mounting groove; where an opening of the breather valve mounting groove is provided in the first side of the end cover or the opening of the breather valve mounting groove is provided in the second side of the end cover. The gas-permeable membrane is mounted on the valve plate, facilitating protection and support for the gas-permeable membrane and reducing adverse impact caused by provision of the first channel on the end cover. The valve plate and gas-permeable membrane of the breather valve are provided in the breather valve mounting groove, so that on the premise of not affecting gas permeation of the breather valve, the breather valve is mounted without occupying the thickness of the end cover to the greatest extent, helping to reduce an overall height of the end cover assembly and the battery. In an end cover assembly according to some embodiments, the breather valve further includes a valve plate. The valve plate is mounted on the end cover and includes a third channel running through two side surfaces of the valve plate. The gas-permeable membrane is fixed to the valve plate and covers the third channel. The breather valve mounting groove is a stepped groove, and the stepped groove includes a first groove section and a second groove section. The first groove section is close to the bottom wall of the breather valve mounting groove, the gas-permeable membrane is located in the fir