High temperature all-solid flexible supercapacitor based on novel cross-linked polybenzimidazole electrolyte

Abstract

A series of cross-linked polymer electrolyte materials is prepared by grafting polybenzimidazole (PBI) containing different hydroxyl (-OH) ratios with 3-(triethoxysilyl) propyl isocyanate (IPTS). Afterwards all-solid supercapacitors are packaged using the cross-linked PBI electrolyte and activated carbon electrodes. The fabricated supercapacitor displays an area capacitance of 314 mF cm−2 at 150°C. After 1000 cycles at 150°C, the device has a capacity retention rate of 85.6%. The capacitance retention rate is 96.1% after 5000 charge/discharge cycles at room temperature, which indicates the assembled supercapacitor has excellent cycle performance.