基于硫化物固体电解质全固态锂电池界面特性研究进展

doi:10.19799/j.cnki.2095-4239.2020.0065

摘要/Abstract

摘要：

采用不可燃的无机固体电解质代替液体有机电解质的全固态锂电池，被认为是解决锂电池燃烧和泄漏等安全问题的终极解决方案之一。同时，锂金属负极的应用可以进一步提高电池的能量密度。近年来，得益于无机固体电解质锂离子电导率方面的突破，硫化物固体电解质被认为是最有前途的锂离子导体之一。然而，在该领域仍有许多挑战亟待解决，主要包括硫化物固体电解质的稳定性、硫化物固体电解质与电极之间的不稳定界面以及锂枝晶的形成与生长。因此，构建稳定的电极/固体电解质界面是实现高性能全固态锂电池的关键。本文针对当前基于硫化物固体电解质全固态锂电池面临的挑战和机遇，总结了目前存在的各种界面问题以及界面调控策略，最后探讨了全固态锂电池可能的研究方向和发展趋势。

关键词: 全固态锂电池, 硫化物固体电解质, 界面

Abstract:

All-solid-state lithium batteries, in which the liquid organic electrolytes are replaced by nonflammable inorganic solid electrolytes, are expected to ultimately resolve the combustion and leakage safety issues of lithium batteries. Meanwhile, a lithium anode is anticipated to improve the energy density. In recent years, breakthroughs in ionic conductivity have identified sulfide electrolyte as a promising ion conductor. However, many challenges in this field remain unsolved, including the stability of sulfide electrolytes, the instability of electrolyte/electrode interfaces, and lithium dendrite formations within the electrolyte. Therefore, a stable solid electrolyte/electrode interface is the keystone of all-solid-state lithium batteries with high performance. Considering the challenges and opportunities for all-solid-state lithium batteries based on sulfide electrolytes, we summarize various interface problems and interface modification strategies. Possible research directions and development trends of sulfide-based all-solid-state lithium batteries are also discussed.

Key words: all-solid-state lithium batteries, sulfide electrolyte, interface

中图分类号:

TM 911

吴敬华, 姚霞银. 基于硫化物固体电解质全固态锂电池界面特性研究进展[J]. 储能科学与技术, 2020, 9(2): 501-514.

WU Jinghua, YAO Xiayin. Recent progress in interfaces of all-solid-state lithium batteries based on sulfide electrolytes[J]. Energy Storage Science and Technology, 2020, 9(2): 501-514.

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