Novel Poly(ethylene oxide)-Based Polymer Gel Electrolytes for Efficient Electrochemical Energy Conversions

Abstract

Polymer gel electrolytes (PGEs) have been extensively studied and used in various electrochemical applications such as lithium secondary batteries and dye-sensitized solar cells (DSC) because of their suitable ionic conductivity and high physical stability. The PGEs should be easily injected into the electrochemical cells to replace the liquid electrolyte and maintain a high ionic conductivity over a wide temperature range. Therefore, in this study, the rheological properties of PGEs have been appropriately controlled by employing various polymer materials derived from poly(ethylene oxide) (PEO). The optimal PGE composition exhibiting both excellent ion conductivity and electrochemical stability has been determined by investigating the combination of various polymer materials including special functional groups and with various glass transition temperatures and molecular weights. In particular, the PEO-based PGEs developed in this study have the advantage of being easy to inject at room temperature and maintaining physical stability and ionic conductivity at a wide temperature with the help of a thermoreponsive behavior of the polymer material selected in this work. The prepared PEO-based PGEs have been evaluated by application to various electrochemical cells such as lithium secondary batteries, dye-sensitized solar cells, and electrochromic devices. The detailed results will be presented and discussed at the conference. This work was financially supported by the Environmental Industry Advancement Technology Development Project of Korea Environmental Industry & Technology (KEITI) funded by Korea Ministry of Environment (MOE) (No. 2017000140002/ RE201702218).