High energy-density solid-state batteries represent a promising alternative to traditional lithium-ion batteries due to their potential for increased energy density, improved safety, and longer cycle life. The development of such batteries has been driven by the need for more efficient and sustainable energy storage solutions in various applications, from electric vehicles to portable electronics. However, there are still challenges to overcome before solid-state batteries can be widely adopted, such as Li dendrite growth, huge Si volume expansion, high solid-electrolyte thickness and interfacial resistances, and large stacking pressure. The group aims to explore the current state-of-the-art in high energy-density (>400 Wh/kg) solid-state batteries, including alloy-based high-capacity anode materials (e.g., Li-Si, Li-Mg, and Li-Al), ultrathin electrolyte membrane, and battery failure mechanism.