Liquid injection explosion-proof pole structure of cylindrical power battery

Abstract

The invention provides a liquid injection explosion-proof pole structure of a cylindrical power battery. The liquid injection explosion-proof pole structure comprises a pole, a pole nut and a safety valve plate, wherein the pole comprises a connection plate and a pole body, the connection plate is provided with the pole body, the pole body is provided with a pole thread, the pole thread on the pole body is matched with the pole nut, a battery cover plate is arranged between the connection plate and the pole nut, the pole nut is cooperated with the pole thread to fix the pole and the battery cover plate under the effect of given pre-tightening force, a liquid injection through hole and a welding step are formed in the pole body, the welding step is arranged on the upper end of the injection liquid through hole, the welding step is connected with the safety valve plate into a whole in a welding manner, the connection plate is connected with a tab inside a battery, and the pole nut is connected with an external conducting wire. The liquid injection hole is integrated with an explosion-proof valve, so that a liquid injection function and an explosion-proof function can be realized by virtue of the form of the pole, the battery structure is simplified, the difficulty that the pole space of the power battery is small can be solved, the over-current capacity of the battery is improved, and the liquid injection efficiency is also improved.

Description

technical field [0001] The invention belongs to the field of lithium ion batteries, and in particular relates to a liquid injection explosion-proof pole structure of a cylindrical power battery. Background technique [0002] In the cylindrical power battery in the prior art, the position of the liquid injection hole and the explosion-proof valve are placed separately on the battery cover, and both occupy a large space on the cover, especially in cylindrical batteries with a diameter of less than 50mm In the cover plate structure, due to the occupation of the liquid injection hole and the explosion-proof valve, the area of ​​the external pole is forced to be reduced, thereby reducing the diversion area of ​​the external connection of the battery and affecting the discharge performance of the battery. In the existing cylindrical power battery, the electrolyte is usually poured into the battery through the circular through hole of about Φ1.5 when the liquid is injected. After t...

AI Technical Summary

Problems solved by technology

Due to the small diameter of the liquid injection hole, slow liquid injection, and sealing by metal extrusion deformation, this technology has technical problems such as long liquid injection time, low efficiency, poor sealing, and riveting dislocation.

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