Cover plate assembly, battery containing same and battery pack

Abstract

The invention relates to the field of lithium ion batteries, in particular to a cover plate assembly, a battery containing the cover plate assembly and a battery pack. The cover plate assembly comprises a cover plate body, and electrode terminals and an anti-explosion sheet which are arranged on the cover plate body, wherein a space ring is arranged on the inner side of the cover plate body; a first exhaust passage is reserved between the space ring and the cover plate body; a second exhaust passage is reserved between the space ring and the anti-explosion sheet; and the first exhaust passage and the second exhaust passage are connected with each other and communicate with the inner space of the battery. The battery comprises a shell, a cover plate assembly for sealing the shell and a pole shank positioned inside the shell, wherein the cover plate assembly is the cover plate assembly provided by the invention; the pole shank and the electrode terminals are connected through pole shank leading sheets; and the space ring is positioned between the pole shank and the cover plate body. The invention also provides a battery pack. The cover plate assembly provided by the invention is provided with the good exhaust passages, the performance of the anti-explosion sheet is good, and the safety performance of the battery can be improved.

Description

technical field [0001] The invention relates to the field of lithium ion batteries, in particular to a cover plate assembly, a battery containing the cover plate assembly and a battery pack. Background technique [0002] With the continuous development of science and technology, lithium-ion batteries are used more and more frequently in all walks of life, and the requirements for the safety performance of lithium-ion batteries are becoming higher and higher. [0003] During the use of lithium-ion batteries, it is inevitable that the internal temperature and pressure of the battery will rise due to various reasons; if the heat or gas inside the battery cannot be discharged in time, it will have a great impact on the service life of the lithium-ion battery. big impact. More seriously, it will cause the lithium-ion battery to explode, seriously affecting the safety of its users. [0004] Therefore, in lithium-ion batteries, the pressure relief and explosion-proof design of th...

AI Technical Summary

Problems solved by technology

However, in the prior art, there is no special exhaust channel between the pole core and the cover plate inside the battery; when an abnormality occurs inside the battery, especially when the pole core expands, it is likely to block the upper explosion-proof plate and break the battery. Open the gas conduction between the inside of the battery and the explosion-proof disk, so that the explosion-proof disk cannot play the role of safe pressure relief

[0005] In addition, the explosion-proof disks in the prior art often use the flat sheet to be thinned and notched to meet the requirements for detonation. When such an explosion-proof disk is welded and combined with the cover plate, due to the thermal effect at the weld, it often leads to explosion-proof damage after welding. Shrinkage and cracking at the notch of the disc will affect the safety performance of the disc

The cover plate in the prior art is flat plate, and the thickness is basically the same; so that when the cover plate and the shell are laser welded, the distance between the welding place and the explosion-proof disk is too small, and the explosion-proof disk needs to be detonated under a certain pressure, so the notch The place will be thinned to a very small thickness, so that the heat generated during the welding process of the cover plate will increase the thermal expansion and contraction effect at the notch of the explosion-proof disk, resulting in rupture of the explosion-proof disk

[0006] The cover plate assembly provided in the above-mentioned prior art, on the one hand, the explosion-proof disk is easily blocked, and cannot play the role of explosion-proof pressure relief; on the other hand, during the assembly process of the explosion-proof disk and the cover plate, it is easy to damage the explosion-proof disk The nicks on the explosion-proof disk cause damage, which affects the use of the explosion-proof disk and will increase the failure rate of the explosion-proof disk

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