Power battery cover plate

Abstract

The invention provides a power battery cover plate, comprising a cover plate body and a plastic part fixed together, and an explosion-proof mechanism and two pole assemblies disposed on the two, wherein one pole assembly is configured to have a positive electrode of a current cutting mechanism; the current cutting mechanism comprises a cavity disposed in the pole piece of the positive electrode, aside through hole connecting the cavity and the outside air is formed on the sidewall of the cavity, and the bottom wall of the cavity is configured with a bottom through hole connecting the cavity and the inner portion of a battery casing; a flipping piece is sealed at the bottom through hole, an outer convex portion facing a connecting assembly is formed in the middle portion, the flipping piece is welded to the connecting assembly via the outer convex portion; a weak connecting portion provided around the outer convex portion is constructed on the flipping piece, and the weak connecting portion may be broken due to an increase in pressure inside the battery casing to break the outer convex portion and the edge of the flipping piece. The power battery cover plate provided by the invention can ensure that the flipping piece is turned over in time when the gas production in the battery case is abnormal, thereby effectively improving the overshoot problem of the power battery.

Description

technical field [0001] The invention relates to the technical field of power batteries, in particular to a power battery cover plate. Background technique [0002] At present, the energy crisis has become a global focus. For example, the price increase of petroleum products used in automobiles or other means of transportation will increase consumers' expenses. Therefore, new energy vehicles have shown various advantages and are rising in the whole world. Automobile industry. As the core power source of new energy vehicles, how to ensure high safety performance is a problem that relevant technicians have been working hard to solve. [0003] Overshoot is the first peak or valley exceeding the set voltage, mainly manifested as a sharp pulse, and can cause circuit components to fail. As a circuit component, the power battery can pass through the overcharge smoothly, or cut off the battery circuit in time before the battery overcharge fails, which is very important for the desi...

AI Technical Summary

Problems solved by technology

[0004] At present, the design of the battery cover mainly adopts the design method of SSD. The principle is that the abnormal gas production inside the battery causes the air pressure in the battery case to increase, and the air pressure acts on the flip valve, causing the flip valve to flip. The entire circuit of the battery is cut off

However, this design has the risk that the overturn valve or safety device fails to act in time, that is, the explosion-proof valve is activated but the overturn valve does not operate, or the overturn valve operates and the safety device cannot be fused in time, which eventually leads to the loss of control or explosion of the battery cell.

Especially in the cell overcharge test, the pass rate is relatively low

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