Cap assembly for cylindrical battery and cylindrical secondary battery

Abstract

The invention provides a cap combination for a cylindrical battery, comprising an upper cap, a lower cover, an explosion-proof ball and a positive connection part, the explosion-proof ball is placed in the accommodation space formed between the upper cap and the lower cover, and the positive connection part is welded on the lower cover The upper and upper caps pass through the hole of the upper cap of the positive connecting part in the center, and an insulating sleeve is provided in the gap formed between the skirt of the positive connecting part and the lower cover, and the insulating sleeve is pressed and compressed by the positive connecting part and the lower cover. The middle part of the insulating sleeve after compression is provided with a negative connection ring, and the edge part of the negative connection ring is welded together with the top of the corresponding steel shell. Also provided is a cylindrical secondary battery manufactured using the cap combination for a cylindrical battery of the present invention. The cap assembly for the cylindrical battery of the present invention has a simple structure, and the cylindrical secondary battery manufactured by using it can increase the use space of the internal battery core, and improve the capacity and safety of the battery.

Description

technical field [0001] The invention relates to a cap assembly for a cylindrical battery and a cylindrical secondary battery. Background technique [0002] As a key component of new energy vehicles, the technical level of power batteries is one of the most critical factors affecting the development of the new energy vehicle industry. However, due to the limited space for battery modules, how to increase the battery capacity per unit volume has become the most important one of the subjects. Existing cylindrical secondary batteries generally include a steel shell, positive and negative electrodes, and a battery core and cap combination formed by winding a diaphragm. The cap combination is formed by a combination of a cap and a sealing ring. The existing cylindrical secondary batteries are generally provided with rolling grooves on the steel shell, and the cap assembly is supported by the rolling grooves, and when the steel shell forms the rolling grooves, the internal space o...

AI Technical Summary

Problems solved by technology

The existing cylindrical secondary batteries are generally provided with rolling grooves on the steel shell, and the cap assembly is supported by the rolling grooves, and when the steel shell forms the rolling grooves, the internal space of the steel shell will be reduced, and The space that the battery can use is only the space between the bottom of the rolling groove and the bottom of the steel case, which reduces the battery capacity per unit volume to a certain extent

Moreover, when the existing cylindrical secondary batteries are connected in series, it is necessary to use the positive connection part in many cases. Extreme phase welding requires multiple welding, and the combination efficiency is low, and this method is easy to increase the internal resistance of the battery, which also increases the space occupied by the battery to a certain extent

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