NATURE

By

Qingshuai Xu, Tan Li, Zhijin Ju, Guangxu Chen, Daiqi Ye, Geoffrey I. N. Waterhouse, Yingying Lu, Xuejun Lai, Guangmin Zhou, Lin Guo, Keyou Yan, Xinyong Tao, Hong Li & Yongcai Qiu

Published

9 January 2025

Abstract

Lithium (Li) metal batteries (LMBs) are promising for high-energy-density rechargeable batteries. However, Li dendrites formed by the reaction between highly active Li and non-aqueous electrolytes lead to safety concerns and rapid capacity decay. Developing a reliable solid–electrolyte interphase is critical for realizing high-rate and long-life LMBs, but remains technically challenging. Here we demonstrate that adding excess m-Li₂ZrF₆ (monoclinic) nanoparticles to a commercial LiPF6-containing carbonate electrolyte of LMBs facilitates the release of abundant ZrF₆^2– ions into the electrolyte driven by the applied voltage, converting to t-Li₂ZrF₆ (trigonal) and creating a stable solid–electrolyte interphase in situ with high Li-ion conductivity. Computational and cryogenic transmission electron microscopy studies revealed that the in situ formation of the t-Li₂ZrF₆-rich solid–electrolyte interphase markedly enhanced Li-ion transfer and suppressed the growth of Li dendrites. As a result, LMBs assembled with LiFePO4 cathodes (areal loading, 1.8/2.2 mAh cm⁻²), three-dimensional Li–carbon anodes (50-µm-thick Li) and Li₂ZrF₆-based electrolyte displayed greatly improved cycling stability with high capacity retention (>80.0%) after 3,000 cycles (1C/2C rate). This achievement represents leading performance and, thus, delivers a reliable Li₂ZrF₆-based electrolyte for durable LMBs under practical high-rate conditions.

Full Text Link

https://www.nature.com/articles/s41586-024-08294-z