Comprehensive Analysis of Anode‐Less Batteries with Lithiophilic Seeds in Liquid and Solid‐State Electrolytes

Abstract Anode‐less batteries, by eliminating the need for conventional active materials on the anode to thereby maximize the energy density and manufacturing efficiency, are at the frontier of next‐generation electrochemical energy storage. Attempts to mitigate lithium (Li) dendrite formation, a persistent problem, have prompted extensive investigations into the use of lithiophilic seed layers on the anode current collector. This paper presents a systematic evaluation of diverse lithiophilic metal thin films as protective interlayers by analyzing their electrochemical and structural behaviors in both liquid and solid electrolyte environments. Liquid electrolyte systems universally undergo rapid capacity decay regardless of the chosen metal, whereas solid‐state systems demonstrate material‐dependent cyclability, with the cycle life predominantly limited by their susceptibility to internal short circuits. This limitation is overcome by developing a dual‐solid electrolyte architecture combined with Li interfacial energy control to significantly enhance the critical current density. This approach enables stable room‐temperature operation of anode‐less all‐solid‐state batteries with 82.8% capacity retention over 150 cycles. This comprehensive investigation elucidates the critical dual role of metal interlayers and the physical state of the electrolyte in governing the performance of anode‐less batteries, and establishes fundamental design principles for advanced anode‐less systems.