Effect of variation in power input on dissimilar materials (Cu-Al) laser welding for battery manufacturing

Abstract

Battery manufacturing inherently requires the joining of dissimilar materials. The performance of a joint is significantly derived from the joining technique as well as the process parameters, which, in turn, determine the life of the product. The current study discusses the efficacy of laser welding to develop dissimilar joints of thin sheets of Al and Cu for battery applications at varying power inputs. Thin sheets of aluminium and copper were welded using laser power inputs of 2.0 kW, 2.1 kW, and 2.2 kW. A power input of 2.1 kW results in 86 % higher weld penetration than the 2.0 kW. High power input results in through-thickness penetration, which drastically affects the mechanical strength of the joint. A weld joint developed at 2.1 kW shows a higher shear load of 800 N among all the power input parameters. An intermetallic layer forms at the weld interface for all three power inputs. However, the width of the intermetallic layer increases with the laser power input.