Conventional cathodes of lithium battery relying on single storage mechanisms-whether intercalation or conversion-face intrinsic limitations in energy density and sluggish electrode kinetics. Hybrid systems combining both mechanisms offer promising pathways to transcend these constraints; yet, their dynamic interfacial synergies remain poorly deciphered at the nanoscale. This study employs multimodal in situ characterization (Electrochemical atomic force microscopy/Raman/Electrochemical impedance spectroscopy) to elucidate the dynamic synergy in TiS2-S hybrid cathodes, revealing the concurrent interfacial evolution during cycling: nanoscale steps formation via Li-ion intercalation in the TiS2-LiTiS2 host and the phase transformation of S-Li2S/Li2S2. Crucially, the TiS2/LiTiS2 serves as a bifunctional interface that not only contributes capacity but also mediates sulfide adsorption and catalyzes preferential edge-directed sulfide deposition. The partially delithiated LixTiS2 enhances electronic conductivity, creating rapid electron transport that facilitates subsequent interfacial sulfide conversion reaction. The hybrid storage mechanism retains features characteristic of both S and TiS2 storage mechanisms, yet manifests synergistic interfacial reconstruction rather than simple superposition, achieving enhanced reversibility, exceptional cycling stability, and superior rate capability.
Tian et al. (2026) studied this question.