Conical surface sealing cylindrical battery and preparation method thereof

Abstract

The invention provides a cylindrical battery with a conical surface seal. The pole group is placed in a steel shell, the steel shell is filled with electrolyte, the sealing ring is set in the steel shell, and the sealing structure is set in the sealing ring. The steel shell The upper end, the corresponding sealing ring, and the side wall of the sealing structure are extruded inward together to form an extruded part whose lower end is an inwardly inclined slope and the upper end is a vertical straight line. ° Bending tightly wraps the top of the steel shell to form a sealing part, the bottom of the sealing structural part is welded together with the upward end of the pole group, the periphery of the base plate of the sealing upper cover plate is welded on the bottom of the sealing structural part, and the safety valve is placed on In the space formed between the sealing upper cover plate and the sealing structure, the downward end of the pole group is welded together with the bottom of the steel shell. A method for preparing the battery of the invention is also provided. The battery of the invention has novel structure, low internal resistance, low cost, good sealing strength and simplified preparation process.

Description

technical field [0001] The invention relates to a cone-surface sealed cylindrical battery and a preparation method thereof. Background technique [0002] Cylindrical secondary batteries mainly include a combination of steel case, negative electrode collector, pole group, positive electrode collector, insulating ring, insulating tape, sealing ring and cap. The existing manufacturing process is generally: positive electrode sheet, separator, negative electrode sheet Wound into an electrode group and fixed with glue, weld the positive electrode collector on the positive end of the electrode group, that is, the part where the positive electrode sheet exceeds the diaphragm, weld the negative electrode collector on the negative end of the electrode group, that is, the part where the negative electrode sheet exceeds the diaphragm, and weld the negative electrode collector on the positive end of the electrode group or Put the insulating ring on the negative end and wrap it with insu...

AI Technical Summary

Problems solved by technology

This preparation process uses more parts and more parts connected by spot welding, and the steel shell needs to be rolled. The rolling groove process will reduce the available space inside the steel shell to a certain extent, and limit the available space of the electrode group of the high-capacity battery. , and in order to prevent the short-circuit between the rolling groove part of the steel shell and the pole group, it is necessary to install insulating tape and insulating ring at the rolling groove position, which also increases the material cost and operation cost to a certain extent, and the sealing of the existing preparation process is made of steel shell Horizontal edging sealing process. In this sealing process, the direction of the sealing edging is perpendicular to the direction of the internal pressure of the battery, and the force structure is not good. When the battery is charged, as the internal pressure of the battery increases, it may break through the edging of the steel shell. The sealing force of the seal will destroy the edge seal of the steel shell, eventually causing the battery to leak, or even the battery to explode

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