Fluoroether Design Enables High-Voltage All-Solid-State Lithium Metal Batteries.

Chen, Yong; Yang, Xu; Wang, Tianyi; Tang, Xiao; Li, Dongfang; Wang, Shijian; Lei, Yaojie; Han, Yu et al. · Adv Mater · 2025

basic_science · Level V

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Abstract

Developing high-voltage all-solid-state lithium metal batteries (ASSLMBs) holds transformative potential for next-generation energy storage technologies but remains a formidable challenge. Herein, a new prototype design is presented that integrates fluorinated ether segments into the traditional oxide nanocomposite phase, enabling poly(ethylene oxide)-based composite electrolytes with exceptional anti-oxidation durability and enhance overall electrochemical performance. Through a combination of experimental and computational analyses, it is demonstrated that the superior performance is attributed to the formation of reconstructed Li⁺ solvation with weakly coordinating environments. The proposed formulation exhibits excellent Li-metal compatibility, enabling stable cycling in symmetric Li||Li cells for over 9500 h. The solid-state electrolyte also exhibits outstanding high-voltage stability with LiNi<sub>0.8</sub>Co<sub>0.1</sub>Mn<sub>0.1</sub>O<sub>2</sub> cathodes, extending the operational voltage from 4.0 to 4.5 V. Moreover, the LiMn<sub>1-x</sub>Fe<sub>x</sub>PO<sub>4</sub>||Li cells have delivered remarkable cycling performance, achieving over 1200 cycles with 99% capacity retention after 500 cycles. This work establishes an innovative platform for designing electrolytes with superior antioxidation properties and enhance structural durability, paving the way for the advancement of high-voltage all-solid-state lithium metal batteries.