(Invited) Metal-Carbon Nanocomposite Anode for Solid-State Li Batteries

Li metal has long been considered as one of the most promising anodes for rechargeable batteries as it can store larger energy than other conventional ones. However, the dendritic growth of Li metal during the plating process aggravates the cycling performance and causes the safety issues, restricting the use of it in commercial batteries. We have found that a silver-carbon nanocomposite layer, when employed in combination with solid electrolyte, prohibits the dendrite formation and allows the homogeneous Li metal plating and stripping on the surface of current collector. The high coulombic efficiency thus achieved also eliminates the need of excessive Li metal, further increasing the cell energy density and decreasing the production cost. The silver particles are dissolved in the Li metal during the charging process and appear to assist the homogeneous Li plating. On the other hand, the carbon layer keeps the solid electrolyte physically separated from Li metal, preventing the chemical degradation of solid electrolyte and the Li metal penetration through it. Consequently, the nanocomposite anode formed on a current collector can offer high energy density and long cycle life in the solid-state batteries.