华南理工大学丘勇才团队报道了用于耐用锂金属电池的Li₂ZrF₆基电解质。相关研究成果发表在2025年1月8日出版的《自然》。

锂（Li）金属电池（LMBs）有望用于高能量密度可充电电池。然而，高活性锂与非水电解质反应形成的锂枝晶，会导致安全问题和快速容量衰减。开发可靠的固体电解质界面对于实现高速率和长寿命的LMBs至关重要，但在技术上仍然具有挑战性。

该文中，研究证明，向LMBs的含LiPF₆的商用碳酸盐电解质中添加过量的m-Li₂ZrF₆（单斜晶系）纳米颗粒，有助于在施加电压的驱动下将丰富的ZrF₆^2-离子释放到电解质中，转化为t-Li₂ZrF₆，并在原位形成具有高锂离子电导率的稳定固体-电解质界面。

计算和冷冻透射电子显微镜研究表明，富t-Li₂ZrF₆固体电解质界面的原位形成显著增强了Li离子的转移，抑制了Li枝晶的生长。因此，用LiFePO₄阴极（面积负载，1.8/2.2mAhcm^-2）、三维锂碳阳极（50-μm厚的锂）和Li₂ZrF₆基电解质组装的LMBs，在3000次循环（1C/2C率）后显示出极大的循环稳定性和高容量保持率（>80.0%）。

研究结果代表了领先的性能，因此，在实际的高速率条件下，为耐用的LMBs提供了可靠的Li₂ZrF₆基电解质。

附：英文原文

Title: Li2ZrF6-based electrolytes for durable lithium metal batteries

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

Issue&Volume: 2025-01-08

Abstract: Lithium (Li) metal batteries (LMBs) are promising for high-energy-density rechargeable batteries1,2,3. However, Li dendrites formed by the reaction between highly active Li and non-aqueous electrolytes lead to safety concerns and rapid capacity decay4,5,6,7. Developing a reliable solid–electrolyte interphase is critical for realizing high-rate and long-life LMBs, but remains technically challenging4,8. Here we demonstrate that adding excess m-Li2ZrF6 (monoclinic) nanoparticles to a commercial LiPF6-containing carbonate electrolyte of LMBs facilitates the release of abundant ZrF62– 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, 1.8/2.2mAhcm2), 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.

DOI: 10.1038/s41586-024-08294-z

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