Application and Technology of Super Soft Welding Ribbon
release time:
2022-08-22
Solar cells will have various welding defects during the welding process, but the common welding defects should be debris, black spots and other phenomena. Whether it is hand welding or machine welding, debris is always unavoidable in the welding process, so the welding debris rate has become an important indicator for the assessment workshop.
Solar cells will have various welding defects during the welding process, but the common welding defects should be debris, black spots and other phenomena. Whether it is hand welding or machine welding, debris is always unavoidable in the welding process, so the welding debris rate has become an important indicator for the assessment workshop. There are many factors that affect the welding debris. This paper mainly considers the force between the welding strip and the cell, and studies the influence of the soft welding strip on the welding debris.
In order to realize the function of generating electricity, the solar modules must connect the monolithic cells to form a whole. The common connection method for crystalline silicon cells is welding. If the battery is not properly controlled during the welding process, it will cause certain defects. These defects may cause hot spots during use, and sometimes seriously affect the life of the module or even burn the module.
The defects that are easy to appear in the welding process are obvious cracks or invisible cracks that can only be seen with the help of tools. The factors that cause this defect are mainly due to the mismatch of thermal stress of silicon material, silver paste and solder ribbon. Due to the instantaneous cooling during the welding process, the temperature drops rapidly from about 250°C to room temperature. The rapid temperature change will generate a lot of stress between the ribbon and the cell, which will cause the bow of the cell after welding. This bow is likely to develop cracks or chips during layup, lamination, and subsequent use.
There are many ways to eliminate thermal stress, such as adjusting the process, changing the welding method, etc. However, adjusting the process requires a lot of experimental data, and the repeatability of the results is not good. Changing the welding method needs to eliminate some old equipment. However, the use of ultra-soft welding tape does not require major changes in process parameters, and has good adaptability to different equipment, so the use of ultra-soft welding tape has significant advantages over other methods.
