Hu Kangjia, Sang Xiaoyu, Chen Jiaxin, Liu Zetong, Zhang Jiahui, Hu Xianluo
State Key Laboratory of Materials Processing and Die & Mould Technology, School of Materials Science and Engineering, Huazhong University of Science and Technology, Wuhan, 430074, China.
Chem Asian J. 2023 Dec 14;18(24):e202300820. doi: 10.1002/asia.202300820. Epub 2023 Dec 5.
High-energy-density lithium-ion batteries (LIBs) with high safety have long been pursued for extending the cruise range of electric vehicles. Owing to the high gravimetric capacity, silicon is a promising alternative to the convention graphite anode for high-energy LIBs. However, it suffers from intrinsic poor interfacial stability with liquid electrolytes, inevitably increasing the risk of thermal runaway and posing serious safety challenges. In this review, we will focus on mitigating thermal runaway of silicon anodes-based LIBs from the perspective of electrolyte design. First, the thermal runaway mechanism of LIBs is briefly introduced, while the specific thermal failure reactions associated with silicon anodes and electrolytes are discussed in detail. We then summarize the safety countermeasures (e. g., thermally stable solid electrolyte interphase, nonflammable electrolytes, highly stable lithium salts, mitigating electrode crosstalk, and solid-state electrolytes) enabled by customized electrolyte design to address these triggers of thermal runaway. Finally, the remaining unanswered questions regarding the thermal runaway mechanism are presented, and future directions to achieve intrinsically safe electrolytes for silicon-based anodes are prospected. This review is expected to provide insightful knowledge for improving the safety of LIBs with silicon-based anodes.
长期以来，人们一直在追求具有高安全性的高能量密度锂离子电池（LIB），以延长电动汽车的续航里程。由于高比容量，硅是用于高能量LIB的传统石墨阳极的一种有前途的替代品。然而，它与液体电解质的固有界面稳定性较差，不可避免地增加了热失控的风险，并带来了严重的安全挑战。在这篇综述中，我们将从电解质设计的角度重点关注减轻基于硅阳极的LIB的热失控。首先，简要介绍LIB的热失控机制，同时详细讨论与硅阳极和电解质相关的具体热失效反应。然后，我们总结了通过定制电解质设计实现的安全对策（例如，热稳定的固体电解质界面、不可燃电解质、高度稳定的锂盐、减轻电极串扰和固态电解质），以应对这些热失控触发因素。最后，提出了关于热失控机制的剩余未解决问题，并展望了实现用于硅基阳极的本质安全电解质的未来方向。这篇综述有望为提高基于硅阳极的LIB的安全性提供有见地的知识。
