Supercapacitors for Extreme Temperatures: A Review

This review considers the literature on electrochemical supercapacitors operating at extreme temperatures from –80 to +220°C, which is very important for practice. The influence of the following methods and factors on the efficiency of the electrochemical supercapacitors at the extreme temperatures is considered: the using of ionic liquids as electrolytes; the using of modified gel electrolyte, a combined electrolyte, aqueous electrolytes with low freezing point; the using of acetonitrile as an electrolyte solvent; the using of clay as a solid electrolyte; application of solid-state electrochemical supercapacitors; application of electrodes with optimized porous structure; the using of graphene and pseudocapacitive electrodes; the using of solar cells; using of combined techniques to create supercapacitors for extreme temperatures. Undoubtedly, this review will be of great interest both for fundamental electrochemistry and for practice.