Dong Liwei, Zhong Shijie, Yuan Botao, Ji Yuanpeng, Liu Jipeng, Liu Yuanpeng, Yang Chunhui, Han Jiecai, He Weidong
MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage, School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin 150080, China.
National Key Laboratory of Science and Technology on Advanced Composites in Special Environments and Center for Composite Materials and Structures, Harbin Institute of Technology, Harbin 150080, China.
Research (Wash D C). 2022 Aug 21;2022:9837586. doi: 10.34133/2022/9837586. eCollection 2022.
High-voltage lithium metal batteries (HVLMBs) have been arguably regarded as the most prospective solution to ultrahigh-density energy storage devices beyond the reach of current technologies. Electrolyte, the only component inside the HVLMBs in contact with both aggressive cathode and Li anode, is expected to maintain stable electrode/electrolyte interfaces (EEIs) and facilitate reversible Li transference. Unfortunately, traditional electrolytes with narrow electrochemical windows fail to compromise the catalysis of high-voltage cathodes and infamous reactivity of the Li metal anode, which serves as a major contributor to detrimental electrochemical performance fading and thus impedes their practical applications. Developing stable electrolytes is vital for the further development of HVLMBs. However, optimization principles, design strategies, and future perspectives for the electrolytes of the HVLMBs have not been summarized in detail. This review first gives a systematical overview of recent progress in the improvement of traditional electrolytes and the design of novel electrolytes for the HVLMBs. Different strategies of conventional electrolyte modification, including high concentration electrolytes and CEI and SEI formation with additives, are covered. Novel electrolytes including fluorinated, ionic-liquid, sulfone, nitrile, and solid-state electrolytes are also outlined. In addition, theoretical studies and advanced characterization methods based on the electrolytes of the HVLMBs are probed to study the internal mechanism for ultrahigh stability at an extreme potential. It also foresees future research directions and perspectives for further development of electrolytes in the HVLMBs.
高压锂金属电池（HVLMBs）可以说是当前技术无法企及的超高密度储能设备最具前景的解决方案。电解质是HVLMBs内部唯一与活性正极和锂负极都接触的组件，有望维持稳定的电极/电解质界面（EEIs）并促进锂的可逆转移。不幸的是，具有狭窄电化学窗口的传统电解质无法兼顾高压正极的催化作用和锂金属负极臭名昭著的反应活性，这是导致电化学性能恶化的主要原因，从而阻碍了它们的实际应用。开发稳定的电解质对于HVLMBs的进一步发展至关重要。然而，HVLMBs电解质的优化原则、设计策略和未来展望尚未得到详细总结。本文综述首先系统概述了HVLMBs传统电解质改进和新型电解质设计的最新进展。涵盖了传统电解质改性的不同策略，包括高浓度电解质以及通过添加剂形成CEI和SEI。还概述了新型电解质，包括氟化电解质、离子液体电解质、砜类电解质、腈类电解质和固态电解质。此外，还探讨了基于HVLMBs电解质的理论研究和先进表征方法，以研究在极端电位下实现超高稳定性的内在机制。本文还展望了HVLMBs电解质进一步发展的未来研究方向和前景。
