Redirecting Bond Cleavage in Sacrificial Prelithiation via Dual‐Side Separator Engineering for Anode‐Free Lithium Batteries

ABSTRACT

Anode‐free lithium metal batteries (AFLMBs) promise extreme gravimetric and volumetric energy densities but suffer from irreversible active lithium loss, sluggish desolvation kinetics, and dendritic proliferation. Herein, we report a catalyst‐induced bond‐cleavage redirection concept to unlock efficient sacrificial prelithiation, implemented via a dual‐side functionalized separator. On the cathode side, a 5 µm MoC _1‐x /NC‐0.3Co coating redirects Li ₂ C ₂ O ₄ decomposition from high‐barrier Li–O cleavage to preferential C─C bond scission. Theoretical calculations and operando characterizations confirm this mechanistic shift, lowering the delithiation potential to 3.79 V at 60°C with a 99.5% Li ⁺ utilization rate. To safeguard the liberated lithium inventory against depletion, the anode side integrates a PSSLi‐PFPE bilayer. This coating accelerates Li ⁺ desolvation and drives the in‐situ construction of a LiF‐rich solid electrolyte interphase, enabling Li symmetric cells cycling for over 1700 h (1.0 mAh cm ⁻² , DOD = 80.7%). Bridging fundamental bond kinetics with practical engineering, the assembled 1.0 Ah anode‐free pouch cell (NCM811||MoC _1‐x /NC‐0.3Co‐LCO/PE/PSSLi‐PFPE||Cu) achieves gravimetric and volumetric energy densities of 458.6 Wh kg ⁻¹ and 1005.2 Wh L ⁻¹ , a power output of 989.1 W kg ⁻¹ , retaining 80.1% capacity after 100 cycles. This non‐invasive separator strategy provides a unified framework connecting bond kinetics to practical cell manufacturing, charting a feasible avenue for high‐energy AFLMBs.