TY  - JOUR
AU  - Xiao, Dewei
AU  - Li, Zhemin
AU  - Yan, Lanxin
AU  - Shi, Jiayin
AU  - Xiong, Jianwei
AU  - Xu, Zhenming
AU  - Dong, Xiaoli
AU  - Zhang, Xiaogang
PY  - 2026
TI  - Separated Solvated Ion Pair-Assisted Aqueous Electrolyte for Supercapacitor at Ultralow Temperature
JO  - Energy Material Advances
SN  - 2097-1133
SP  - 0189
VL  - 7
AB  - Aqueous electrolytes have the advantages of low cost, environmental friendliness, and fast ion transport kinetics, which show great low-temperature potential. However, the high freezing point limit practical applications. In electrolytes, the design of ion pairs can effectively improve the charge transport properties, while its effect on low-temperature performance is neglected. Here, we acquired the lithium trifluoromethanesulfonate (LiOTf)-based aqueous electrolytes with different ion pair structures. Using advanced characterization and simulation, it was revealed that the 10 m LiOTf electrolyte-enriched separated solvated ion pairs (SSIPs) show excellent ultralow-temperature stability. The changes in energy storage behavior under different temperature were discussed, which revealed that SSIPs contribute to efficient adsorption at low temperatures. The supercapacitor with 10 m LiOTf reached high energy density of 34.67 Wh/kg at −40 ℃ and maintained long cycle stability at −70 ℃. Our work suggests a strategy for the rational design of electrolytes that could enable next-generation ultralow-temperature electrochemical storage systems.
UR  - https://doi.org/10.34133/energymatadv.0189
DO  - 10.34133/energymatadv.0189