Planar Li deposition and dissolution enable practical anode-free pouch cells

Anode-free lithium metal batteries (AFLMBs), which are manufactured without anode active material, offer great potential for high-energy-density, low-cost energy storage. However, AFLMBs face a long-standing challenge of short lifespan due to the harsh conditions of lacking excess Li-resource and an anode host 1-8 . This issue is associated with uneven Li deposition/dissolution, rooted in the micro-heterogeneity and mechanical fragility of solid electrolyte interphase (SEI) 9 . Here we report a practical 500 Wh kg –1 -level AFLMB with enhanced lifespan, achieved using a crossover-coupled electrolyte. The electrolyte triggers crossover-coupled interfacial reactions that generate a B–F-based polymer-rich SEI at the anode while suppressing gas evolution at the cathode. The resulting SEI exhibits sub-nanometer homogeneity, high flexibility, and rapid Li-ion transport, and it spontaneously develops a self-adaptive mesh-film structure that ensures uniform ion flux and large-volume-change accommodation, thereby realizing reversible planar Li deposition/dissolution of 5.6 mAh cm –2 . Consequently, a 2.7 Ah AFLMB (508 Wh kg –1 , 1668 Wh L –1 ) without any host-material coating demonstrates stable cycling for 100 cycles at 100% depth of discharge (DoD) and 250 cycles at 80% DoD, with 80% capacity retention and a high-power output of 2650 W kg –1 at 96 Wh kg –1 . These findings establish crossover-coupled interphase chemistry and address the inherent structural instability of host-free electrodes, advancing the practical implementation of AFLMBs.