Self-Activated Liquid-Metal Hosts Stabilize Anode-Free Aluminum Batteries

Anode-free aluminum batteries offer a promising route toward high energy density and low-cost energy storage, but their development is limited by uncontrolled Al nucleation/growth and cumulative irreversible Al loss during cycling. Here, we report a Ga-In-Sn liquid-metal-modified carbon cloth, LM@CC, as a self-activated interfacial host for anode-free graphite aluminum batteries in molten-salt electrolytes at 100°C. Upon exposure to the molten salt after cell assembly, LM@CC spontaneously reconstructs and undergoes in situ pre-aluminization, forming an intrinsically aluminophilic and electrochemically activated interface before cycling. This adaptive liquid-metal interface lowers the Al nucleation overpotential, accelerates interfacial charge transfer, and guides spatially uniform Al deposition/stripping. Consistent with these interfacial advantages, LM@CC-based symmetric cells sustain stable Al plating/stripping for approximately 1000 h at 1 mA cm^-2 and 5 mAh cm^-2. As a result, the graphite||LM@CC anode-free full cell operates for over 20 000 cycles at 2 A g^-1 and 80 000 cycles at 10 A g^-1 with average Coulombic efficiencies of 99.60% and 97.79%, respectively. These findings highlight interfacial reconstruction as a route to stable, high-rate anode-free aluminum batteries.