Turning on Lithium-Sulfur Full Batteries at -10 °C.

Kim, Hun; Hwang, Jang-Yeon; Ham, Young-Geun; Choi, Ha-Neul; Alfaruqi, Muhammad Hilmy; Kim, Jaekook; Yoon, Chong Seung; Sun, Yang-Kook · ACS Nano · 2023

basic_science · Level V

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Abstract

Lithium-sulfur (Li-S) batteries using Li<sub>2</sub>S and Li-free anodes have emerged as a potential high-energy and safe battery technology. Although the operation of Li-S full batteries based on Li<sub>2</sub>S has been demonstrated at room temperature, their effective use at a subzero temperature has not been realized due to the low electrochemical utilization of Li<sub>2</sub>S. Here, ammonium nitrate (NH<sub>4</sub>NO<sub>3</sub>) is introduced as a functional additive that allows Li-S full batteries to operate at -10 °C. The polar N-H bonds in the additive alter the activation pathway of Li<sub>2</sub>S by inducing the dissolution of the Li<sub>2</sub>S surface. Then, Li<sub>2</sub>S with an amorphized surface layer undergoes the modified activation process, which consists of the disproportionation and direct conversion reaction, through which Li<sub>2</sub>S is efficiently converted into S<sub>8</sub>. The Li-S full battery using NH<sub>4</sub>NO<sub>3</sub> delivers a reversible capacity and cycling stability over 400 cycles at -10 °C.