Three dimensional simulation of high speed remote laser cutting of cathode for lithium-ion batteries

Cut surface quality of electrodes' affect lithium-ion battery performance. Current uses of mechanical cutting require expensive tooling. Furthermore, tool wears out over time so that it results in process instability and poor cut quality. This may cause an internal short circuit and significant heat generation. These problems can be solved by using a laser cutting technique since it has many advantages, such as no tool wear, high energy concentration, fast processing speed, very narrow heat affected zone, applicability to nearly all materials, and flexibility of laser power. Understanding physical phenomena provides significant advantages to fully utilize the remote laser cutting of electrodes for lithium-ion batteries. In this paper, a 3D mathematical model of three-dimensional self-consistent remote laser cutting is developed for cathode (LiCoO2-coated aluminum) of lithium-ion batteries. Characteristics of the remote laser cutting of cathodes, liquid/vapor (L/V) interface geometry, and melt pool flow are investigated by computational analysis at the laser power of 150W and scanning speed of 5000mm s(-1). Experimental results validate the proposed computational model and show in good agreement with computationally observed results in terms of the kerf width and aluminum composition changes along the vertical line of the cut surface. (C) 2016 Laser Institute of America.