Anode-Free Batteries: The Energy Density Prize and the Stability Paradox

The anode-free architecture represents the theoretical end point for battery energy density, a prize now being realized in practical pouch cells exceeding 500 Wh kg–1. This design, however, causes a profound stability paradox: the very act of hostless metal plating induces complex electro-chemo-mechanical failure modes that severely degrade cycle life. This review critically analyzes this central conflict from the perspective of industrially relevant pouch cells. We elucidate a decisive paradigm shift in mitigation strategies, moving away from passive, monolithic materials toward the design of dynamic, multifunctional systems. The most successful approaches engineer a synergistic interplay between advanced electrolytes, architected current collectors, and precise operational protocols. These solutions function not as static barriers but as programmable, process-controlling systems that actively manage the anode interface. Securing the anode-free prize depends on mastering this new methodology of synergistic design.