Lithium sulfur battery (LSB) has great potential as a promising next-generation energy storage system owing to ultra-high theoretical specific capacity and energy density. However, the polysulfide shuttle effect and slow redox kinetics are recognized the most stumbling blocks on the way of commercializing LSB. On this account, for the first time, we use Ti^x+ in-situ intercalation strategy via titanium foil/vanadium ion (V⁵⁺) solution interface to modify the layer of vanadium oxide for long cycle LSB. The inserted Ti^x+ strengthens interlayer interaction and enhances lithium-ion mobility rate. Meanwhile, based on density functional theory (DFT) calculation, the mixed valence of V⁵⁺/V⁴⁺ in the vanadium oxide structure reduces the stress and strain of lithium-ion intercalation through the interlayer support of titanium ions (Ti^x+). Also, Ti^x+ refines the structural stability of the sulfur wrapped composite matrix so as to facilitate the LiPSs transformation, and improve the electrochemical performances. Consequently, the Ti-VO_2.375/S cathode delivers a lower capacity decay of 0.037 % per cycle over 1500 cycles with a stable coulombic efficiency around 100 %.

锂硫电池（LSB）由于具有超高的理论比容量和能量密度，作为一种有前途的下一代储能系统具有巨大的潜力。然而，多硫化物穿梭效应和缓慢的氧化还原动力学被认为是LSB商业化的最大障碍。为此，我们首次采用Ti ^x+通过钛箔/钒离子(V ⁵⁺ )溶液界面的原位插层策略来修饰氧化钒层以获得长周期LSB。插入的Ti ^x+增强了层间相互作用并提高了锂离子迁移率。同时，基于密度泛函理论（DFT）计算，钒氧化物结构中V ⁵⁺ /V ⁴⁺的混合价态通过钛离子（Ti ^x+ ）的层间支撑降低了锂离子嵌入的应力和应变。此外，Ti ^x+还改善了硫包裹复合基体的结构稳定性，从而促进 LiPSs 转化，提高电化学性能。因此，Ti-VO _2.375 /S 阴极在 1500 个循环中每个循环的容量衰减较低，为 0.037%，库仑效率稳定在 100% 左右。