Chengdu Liang , Yongsheng Guo, Chengyong Liu

Research Institute,

Ningde Contemporary Amperex Technology Limited，

Fujian Province 352100, China

The energy density of lithium ion batteries is now approaching the theoretical limit. Therefore, the development of next-generation batteries is of great technical interest nowadays. Solid state lithium batteries have attracted considerable attention because the replacement of an organic liquid electrolyte with a safer and more reliable inorganic solid electrolyte simplifies the battery design and improves safety and durability of the battery ^[1].

A crucial material to develop solid state batteries is a solid electrolyte with high Li⁺ ion conductivity at room temperature. Among different kinds of solid electrolytes, inorganic sulfide-based solid electrolytes are one of the most promising candidates for solid state lithium batteries due to the high ionic conductivity, wide electrochemical window and ease of forming framework structures ^[2-3]. However, there are still many challenges for the commercialization of solid state lithium batteries with sulfide-based electrolyte ^[4-5], for instance, the electrolyte/electrodes interface and air stability of sulfide-based electrolytes need to be further improved, and advanced manufacturing technologies are required as well.

In this presentation, several strategies to enhance ionic conductivity of sulfide-based solid electrolytes are deliberated; an ionic conductivity as high as 3.0 mS/cm has been achieved. We will then summarize the research progresses of solid state lithium batteries with sulfide-based electrolytes based on our work. Future research trends and perspectives for facilitating further improvement on the performance of sulfide-based solid state batteries will also be discussed.

Reference

[1] CW Sun, Nano Energy 33 (2017) 363.

[2] ZC Liu, CD Liang, J. Am. Chem. Soc., 135(3) (2013) 975.

[3] D. Liu, Materials Science and Engineering B 213(2016)169.

[4] A. Sakuda, Solid State Ionics 285 (2016) 112.

[5] J. C. Bachman, Chem. Rev. 2016, 116, 140.