Multipaths Li+ Migration and In Situ Interfacial Alloying of Composite Solid-State Electrolyte Enables High-Performance All-Solid-State Lithium Metal Batteries.

作者：Ying‐Ying Zhang, Xiang Xiao, Hao Yin, Qing-Song Liu, Xiu-Li Wang, Guo-Rui Zhu, Gang Wu, Yu-Zhong Wang · 发表于：Small · 年份：2025 · DOI：10.1002/smll.202509107 · 被引用次数：3 · 研究领域：Medicine

Polyethylene oxide (PEO)-based electrolytes face critical challenges of interfacial instability and lithium dendrites in ASSLMBs. Herein, porous BiF3 nanoparticles with channel structures and reactivity were synthesized via a one-step precipitation method and introduced into PEO to construct a novel composite solid-state electrolyte (CPE) with enhanced interfacial stability and high ionic conductivity. Density functional theory (DFT) calculations verify that BiF3 nanoparticle promotes lithium salt dissociation, thereby increasing the mobility of free Li+, while its channel architecture establishes more paths for Li+ transport. Furthermore, BiF3 undergoes an in situ alloying reaction with the lithium anode to form LixBi and LiF, so as to build a gradient composite solid electrolyte interphase (SEI), which demonstrates exceptional interfacial stability and rapid Li+ transport kinetics, effectively inhibiting lithium dendrite propagation. As a result, Li|Li symmetrical cell with PEO-5%BiF3 CPE achieves stable cycling over 6000 h at 0.1 mA cm-2 without short-circuiting, and its Li|LFP full cell exhibits exceptional electrochemical performance across a wide temperature range (45-90°C). Moreover, it also demonstrates excellent cycling stability and capacity retention in Li|NCM811 system. Notably, the excellent electrochemical performance and safety of Li|PEO-5%BiF3 CPE|LFP pouch cell demonstrate good application potential.