Toward Zero-Excess Alkali Metal Batteries: Bridging Experimental and Computational Insights.

This review introduces alkali metal (Li, Na, and K) anode-less and anode-free batteries and conveys a synopsis of the current challenges regarding anode-electrolyte interfaces. The review focuses on a critical analysis of the fundamental understanding of the (eletro)chemical and (electro)physical processes occurring at the anode, including metal nucleation and dendrite growth, the properties of liquid and solid electrolytes, and their roles in the metal stripping/deposition process and the formation of solid-electrolyte interphase, and the properties of separators and their role in inhibiting dendrite growth. Solutions to tackle the challenges for anode-less and anode-free batteries are discussed extensively in the aspects of the modifications of the anode substrate, novel electrolyte solutions and SEI structures, interface design, and novel separators/solid-state electrolytes to enable stable battery performances. To highlight the importance of bridging experimental and computational insights, experimental progress derived from a range of advanced characterization techniques is analyzed in combination with the advancement in multi-scale theory and computational modeling. Finally, outlooks are provided from both experimental and computational points of view for the exciting field of zero-excess alkali metal batteries.