Penetrating type laser welding method of solar cell bus bars

Abstract

The invention relates to a penetrating type laser welding method of solar cell bus bars. The method comprises the following steps: outputting a laser beam through a pulse laser device, carrying out beam expansion control on diameter of the laser beam through a beam expander, focusing the laser beam subjected to beam expansion on a welding sample through a laser welding head, and enabling the laserwelding head to horizontally move up and down to adjust the size of a laser focal point and a laser welding spot; applying pre-pressure to a position near an area to be welded through a pre-pressingmechanism to enable two layers of welding strips to be in full contact with each other; receiving thermal radiation reflection laser in the welding process through a temperature feedback system, collecting a welding thermal radiation laser beam and converting the welding thermal radiation laser beam into temperature information, and calibrating the temperature of the welded area; enabling a visualimage system to move up and down to adjust a visual image focal point and identifying position information of the welding sample; focusing pulse laser on the welding strips, forming extremely high laser energy density in an action area, directly gasifying tin on the surface layers and copper on the inner sides of the welding strips, forming cavities in the materials and enabling the materials tobe tightly occluded with each other, and directly carrying out fusion welding of copper layers of the two layers of welding strips. The welding quality is high.

Description

Technical field [0001] The invention relates to a penetrating laser welding method for solar cell bus bars, and belongs to the technical field of laser processing. Background technique [0002] At present, with the rapid development of global technology and economy, more and more cleaner energy sources are increasingly needed to meet the demand. Solar energy resources do not emit carbon dioxide when generating electricity and have a small environmental burden. Therefore, many countries and regions are vigorously developing solar energy (such as photovoltaic) cells as energy sources. [0003] Monolithic solar cells have limited effects, and solar cell modules have become a better choice. To realize the function of generating electricity, solar cell modules need to connect single solar cells to make them into a whole. At present, bus bars are used for the purpose of connecting and converging in the solar cell module packaging process. [0004] The bus bar soldering strip is a tin-co...

AI Technical Summary

Problems solved by technology

This welding method has disadvantages such as complex welding process, cost of consumables such as flux, material residue and oxidation problems at the soldering end of the electric soldering iron for a long time, which may easily lead to poor welding. It is increasingly unsuitable for intelligent, high-efficiency, and high-quality solar cell modules manufacturing development needs

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