AI-screened small-molecule templating effect enabling 2D architectures for dendrite-free lithium metal batteries

Filler-reinforced composite polymer electrolytes (CPEs) possess enhanced ionic conductivity but remain inadequate for dendrite suppression. Herein, anisotropic Li_6.25Al_0.25La₃Zr₂O₁₂ (LALZO) nanosheets (LNSs) are introduced to address this problem. They are synthesized via an AI-screened small-molecule-templated sol-gel strategy. Descriptor-guided molecular screening identified sucrose and citric acid as a synergistic molecular couple, driving cooperative chelation-hydrogen-bond assembly and steering the two-dimensional crystallization of LALZO. Notably, this methodology exhibits broad versatility, extending to the synthesis of other 2D oxides such as LATP and Al₂O₃. Incorporated into CPEs, the LNSs establish continuous Li⁺ transport pathways, enhancing ionic conductivity. More importantly, the high-aspect-ratio LNSs enhance mechanical performance, and the 2D architectures form a brick-and-mortar-like skeleton that dissipates local stress and constructs physical barriers, collectively deflecting dendrite growth. This coupled electrochemical-mechanical enhancement enables stable cycling over 3,000 h with Li metal. Full cells with LiFePO₄ cathodes retain 96.7% capacity after 300 cycles.