Enhancing all-solid-state battery performance through multi-walled carbon nanotube additives in the infiltration process

The growing global demand for e-mobility has heightened the focus on developing safer and more efficient battery technologies. Conventional batteries with liquid electrolytes present considerable fire hazards due to their organic liquid components. In response, all-solid-state batteries (ASSBs) have garnered significant attention due to their potential to enhance both safety and energy density. Nevertheless, critical challenges persist, particularly at the solid-solid interfaces, where poor interfacial contact induces elevated internal resistance and hampers overall cell performance. Furthermore, the role of electronically conductive additives within composite cathodes-and their impact on the electrochemical stability and capacity contribution of solid electrolytes-remains insufficiently understood. In this study, we investigate the impact of replacing Super P Carbon Black (SPB) with Multi-Walled Carbon Nanotubes (MWCNTs) in the infiltration process. Our findings indicate that MWCNTs enhance battery performance by providing sites for SE recrystallization. While SPB is prone to side reactions, resulting in lower initial Coulombic efficiency (ICE), MWCNTs, despite also undergoing side reactions, exhibit better performance. This is evidenced by the increased ICE observed in carbon-free configurations. The enhanced performance with MWCNTs underscores the importance of optimizing conductive additives to achieve high-efficiency ASSBs.