Development of laser structured three-dimensional patterns for improved wettability and performance of electrodes for lithium-ion batteries

The demand for improved performance and higher energy density of LIBs is growing due to their wide range of applications and advancement in the energy storage market for electric vehicles. Three-dimensional (3D) structured electrodes have recently been considered the best and most promising approach to improve battery performance as they exhibit high areal and specific capacity. In the work described here, a nanosecond pulsed fiber laser was used to generate four types of surface patterns named: line, grid, triangular end, and rectangular end patterns with an equal amount of ablated active material volume. A study on wettability was performed using the spread area, wetting time, wetting balance, and capillary rise measurements. Moreover, the Lucas Washburn and extended wettability models were used to quantitatively express the wetting behavior using the term wetting rate. In all approaches, line-patterned electrodes show better wettability along with a higher wetting rate, while poor behavior is seen with an unstructured electrode. Galvanostatic tests were used to examine how these electrode surface patterns influence the electrochemical performance of the battery. The capacity retentions, discharge capacity efficiencies, and cyclic stabilities were improved on cells with line, triangular end, and rectangular end patterned electrodes.