Recent progress in all-solid-state Li-ion battery anodes

Recently, there has been significant research activity in the field of energy storage systems with a focus on improving the energy density and safety of Li-ion batteries (LIBs). The liquid-state electrolytes used in LIBs have several safety issues, including flammability and decomposition due to exothermic reactions during repeated cycles. Addressing the flammability issue is particularly important for the widespread adoption of eco-friendly electric vehicles. As a result, all-solid-state batteries (ASSBs) that use stable and non-flammable solid-state electrolytes are being considered as an alternative solution. The use of solid-state electrolytes can also address concerns about thermal runaway, and research into adopting Li metal anodes is being conducted to achieve high-energy-density ASSBs. However, the problems of Li dendrite formation and solid electrolyte dissociation due to the reaction between Li and solid electrolyte still exist in ASSBs. To address these issues, many researchers are actively studying various types of anodes for ASSBs, including Li-metal, Li-interlayer, anode-free, carbon-based, oxide-based, and Li-alloy-based ASSB anodes. This study reviews recent progress and issues related to various types of ASSB anodes.