A precision welding method and device for a power battery

Abstract

The invention discloses a precision welding device for a power battery, which includes a frame and two shifting mechanisms, which are movably installed on the frame and can be alternately positioned at a welding station and a discharging station; Two welding fixtures are respectively installed on the two shifting mechanisms for clamping and positioning of the power battery; two distance measuring modules are respectively installed on the two welding fixtures for measuring the distance between the distance measuring module and the welding fixture. The distance between the end face of the power battery to be held; two welding modules are respectively installed on both sides of the shifting mechanism, and the power battery in the welding fixture is welded simultaneously according to the measured value of the distance measuring module. The invention also discloses a precise welding method for a power battery. The welding device and welding method of the present invention can not only accurately position the casing with low manufacturing precision and large deformation, but also realize effective inspection and elimination of defective products after welding.

Description

technical field [0001] The invention relates to battery welding technology, in particular to a precise welding method and device for power batteries, which are suitable for pre-spot welding of both side cover plates of square batteries. Background technique [0002] With the maturity and improvement of electric vehicle technology, electric vehicles and hybrid vehicles have gradually entered daily life, and their widespread popularization has given birth to huge business opportunities. However, due to the complex use environment, the safety performance requirements of the battery are extremely strict, and the performance of the power battery itself directly affects the overall performance of the electric vehicle. Among them, battery welding is an extremely critical link in the production and manufacture of power batteries. [0003] At present, for prismatic batteries that need to be welded on both sides of the cover plate, the industry usually divides the welding of the cove...

AI Technical Summary

Problems solved by technology

[0004] However, in the laser spot welding process, the assembly accuracy is high, and the pressing gap between the cover plate and the shell needs to be small (within 0.1mm), so the control is difficult; at the same time, the battery shell is getting thinner and thinner, and its own deformation is large. Manufacturing dimensional errors are large, so high-precision welding fixtures are required to ensure the yield rate and welding efficiency during batch welding

[0005] In addition, the existing detection methods cannot meet the actual production needs and cannot effectively inspect defective products

For example, CCD visual recognition is greatly affected by factors such as environmental light source, battery case surface finish, scratches, etc., which can easily lead to false recognition, and the pixel requirements are high and the cost is high.

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