Exploring Stability of Nonaqueous Electrolytes for Potassium-Ion Batteries
journal contributionposted on 11.05.2018, 00:00 by Yu Lei, Lei Qin, Ruliang Liu, Kah Chun Lau, Yiying Wu, Dengyun Zhai, Baohua Li, Feiyu Kang
Recently nonaqueous potassium-ion batteries (KIBs) have attracted tremendous attention, but a systematic study about the electrolytes remains lacking. Here, the stability of a commonly used electrolyte (KPF6 in ethylene carbonate (EC) and diethyl carbonate (DEC)) at the anodes (e.g., graphite, solid K, and liquid Na–K alloy) was studied. Interesting results show that the linear DEC is unstable. Possibly attributed to stronger reducibility against the anodes for KIBs, the decomposition of DEC is initiated by the C(H2)–O bond breaking of the solvent molecule. This study shows that a systematic study to look for a more stable electrolyte is critically important for KIBs.