Metal-Carbon Dual Buffer Layer Development to Suppress Lithium Dendrite Growth in All-Solid-State Batteries

Mitigating the dendritic lithium-metal growth stemming from heterogeneous lithium-metal deposition remains an important challenge to suppressing short-circuit in all-solid-state batteries. This work employs direct current magnetron sputter coating to deposit various metal nanoparticles (Ag, Au, Mg, and Sn) on a current collector to achieve uniform lithium-metal plating and improve cycling performance. The Sn nanoparticles deliver improved cycling performance compared to the other metal nanoparticles at a current density of 1 mA cm⁻² at 50 °C. Next, a dual buffer layer of Sn and C, where a thin C layer is deposited on top of the Sn-metal layer, is proposed to prevent lithium dendrite growth and extend cycling stability further. The Sn–C dual buffer layer shows stable Li-plating/stripping cycling over 400 cycles without noticeable short-circuit. This presentation will discuss the role of the dual buffer layer in suppressing lithium dendrite growth.