Halide Perovskite as Anode for Lithium-Ion Batteries With High Rate Performance

Hybrid halide perovskites (HPs) exhibit soft lattice frameworks and intrinsic ion-migration characteristics, suggesting potential tolerance toward foreign-ion insertion beyond their established optoelectronic applications. However, their structural evolution and electrochemical reaction pathways under lithium insertion remain largely unexplored. In this work, CH 3 NH 3 PbI 3 films were fabricated on Cu foil via a facile drop-casting method and systematically investigated as model electrodes for lithium-ion storage. The initial discharge capacity reaches 310.4 mA h g −1 and stabilizes at approximately 120 mA h g −1 after 160 cycles at moderate current density. Detailed electrochemical and structural analyses reveal a multistep lithiation process involving Li + insertion, partial reduction of Pb(II) species, and interfacial alloying reactions accompanied by progressive lattice degradation. The results provide insights into ion-induced structural transformation and interfacial chemistry in HPs under electrochemical environments. Considering their compositional tunability and structural flexibility, HPs may serve as a versatile platform for exploring functional electrochemical layers. Graphical Electrochemical characterization shows that MAPbI 3 halide perovskite is not merely electrochemically active for lithium storage, but undergoes coupled bulk and interfacial evolution during cycling. Materials characterization and schematic analysis reveal that lithium-ion insertion drives lattice distortion in the soft perovskite framework, while near the Cu current collector, the perovskite gains electrons and is reduced to metallic Pb.