Factors influencing the welding process to generate the phenomenon of cut off fingers in photovoltaic modules

Abstract

In the production process of photovoltaic modules, there are defects of bad welding, defects in the raw material, degradation by environmental factors, as well as bad handling of the material or lack of maintenance, affecting the quality of the product. The omission of control of the temperature in the welding process causes the defect called cut fingers, which consists of the rupture presented by the collectors of the cell. The present research focused on studying the factors that influence the welding process for the generation of cut fingers, emphasizing the temperature measurement during the welding process. The methodology used consisted of describing the materials involved in the welding process and monitoring the temperature in the welding machine, as well as the ambient temperature. Some cells without solder were found. The temperature variation in the welding heads ranged from -14.9 to -121 ° C. With this study it is concluded that the temperature of the welding heads should continue to be monitored, since the variation is out of specification, the pH of the fluss must be verified, and the periodicity of its distillation must be determined to purify it and be able to reuse it.