Ultra-wettable liquid metal interface for highly durable solid-state lithium batteries

The advent of solid-state batteries (SSBs) featuring Li metal anodes heralds a momentous opportunity for electrified transport with enhanced safety and remarkable energy density. Nevertheless, the intrinsic lithiophobic nature of solid electrolytes will give rise to inevitable vacancies and voids at the interface between solid electrolytes and Li metal, resulting in pronounced local current accumulation and dendrite formation. Here, an ultra-wettable interface between the solid electrolyte and the metal anode is established, ensuring a seamless connection at the atomic level, accomplished through the incorporation of a liquid metal. It is demonstrated that the interface facilitates the formation of a homogeneous and unbroken Li+ transportation pathway, promoting rapid and stable Li+ transport across the interface. In this regard, the SSBs exhibit exceptional durability for extended periods of over 7,200 h and exhibit favorable performance at various rates. This strategy paves an avenue for designing highly steady SSBs.