Hybrid gel polymer electrolyte with good stability and its application in electrochromic device

Using propylene carbonate (PC) as solvent, a hybrid gel polymer electrolyte (GPE) based on poly(propyleneglycol) bis(2-aminopropyl ether) (2-APPG) and 3-isocyanatepropyltriethoxysilane (ICS) was successfully synthesized by sol–gel method. The result shows the hybrid gel polymer electrolyte with [O]/[Li] ratio of 22 has a high ionic conductivity, good thermal stability, as well as good electrochemical stability. The ionic conductivities reach as high as 1.43 × 10 − 3 S cm − 1 at 30 °C and 3.36 × 10 − 3 S cm − 1 at 100 °C, respectively. Nearly 0 weight loss was observed up to 100 °C. The electrochromic device is fabricated by using the hybrid gel polymer as electrolyte. The results demonstrate its high coloration efficiency (267.4 cm 2 C − 1 ) and long cycle life (150 cycles with the linear potential sweep between − 3.5 and + 2.5 V), When the applying voltage is increased to as high as 5 V on the electrochromic device, a fast response is obtained (colored/bleached time are 13/19 s), which indicates its potential application under high voltage conditions.