Cycling Efficiency Improvement of Solid-State Batteries-Laser Textured Interfaces

Solid-state lithium metal batteries (SS-LMBs) with ceramic electrolytes have attracted significant interest towards their potential to produce safe and powerful storage devices. Among ceramic electrolyte materials utilized in SS-LMBs, non-flammable perovskites (La2/3-xLi3xTiO3, LLTO) are cost-effective and have a wider electrochemical window than conventional liquid electrolytes (> 5V). However, the high interfacial resistance at the LLTO/cathode interface restricts the reversible capacity and the cycling efficiency of SSLMBs. Herein, a novel approach of laser texturing at the interface was investigated as a solution to these two challenges. In this study, the laser-texturing technique was first used to produce micro-patterns on the side of the LLTO against the cathode. This increased surface contact area provided more pathways for Li-ion migration at the interface, leading to decreased interfacial resistance and an improved battery energy density. A few drops of liquid electrolyte were added to fill the void spaces between the laser-textured LLTO and the cathode. Overall, this study conceptually proved the effectiveness of using laser texturing to improve the interfacial contact. Further efforts are needed to optimize the pattern design and establish a more stable interface that could enable long-term cycling of the SS-LMBs.