Comparison and Selection of Membrane Material for Supercapacitors Based on Aqueous Electrolytes

Abstract

The membrane/separator is an important part of electrochemical energy storage devices such as supercapacitors and batteries. However, the transport processes that limit the rate capability of the charge/discharge are more pronounced for supercapacitors, which can be charged in seconds, unlike batteries; therefore, a more detailed selection of the material and porosity of the membranes is required for them. The paper shows a method for estimation of the contribution of additional membrane resistance by the cyclic voltammetry. As a result of a comparative analysis of 4 membranes: cellulose based separator TF4050 and VL100 (Nippon Kodoshi Corporation, Japan); filter paper - blue ribbon "OOO Melior XXI" (filter); filter based on polyvinylidene fluoride (PVdF) (Durapore® Membrane Filter) it was determined that the membrane based on PVdF has the least additional resistance in a concentrated solution of LiCl, while in concentrated solution of NaClO4 the least additional resistance has TF4050. In general, for preliminary electrochemical studies, the possibility of using not specialized membranes under certain conditions has been shown.