Polymer Electrolyte Application in Electrochemical Devices

Since liquid electrolytes produce high conductivity at room temperature, it has been frequently used in many energy devices. However, liquid electrolyte may vaporize at elevated temperatures. Therefore, polymer electrolytes, which exist in a solid or gel form, become one of the best alternatives to replace the liquid electrolyte. Polymer electrolyte is one of the main components that influence the magnitude of the current density, number of cycles, and capacity of electrochemical devices. Although a solid polymer electrolyte possesses good mechanical strength, it exhibits poor conductivity at room temperature. By combining the advantage of both liquid and solid electrolytes, gel polymer electrolyte was then introduced. In order to improve the ionic conductivity of the electrolyte, ionic liquid and nanomaterials such as SiO2 TiO2 Al2O3 were added to the system. This chapter concentrates on the applications of polymer electrolytes in various devices, namely, lithium-based batteries, electrochromic window, electrochemical double-layer capacitors, fuel cells, and dye-sensitized solar cells.