LAUSR

Abstract Supercapacitors (SCs), a type of energy storage devices, have dragged an attention worldwide due to its high electrochemical performance for various applications. However, the use of liquid electrolyte in SCs spresents several drawbacks on packaging and security. Therefore, the preparation of SCs using solid electrolytes is a feasible method. Here, we report an ionogel electrolyte (PAAm/IL-X) which composed of polyacrylamide (PAAm) network and ionic liquid 1-vinyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([VMIM][TFSI]). The introduction of ionic liquid ([VMIM][TFSI]) improves the thermal stability and conductivity of the electrolyte. The conductivity of the prepared ionogel is up to 23 mS cm−1 at 90 °C, which still retained 71% even after 20 days at room temperature. It is noted that the thermal decomposition temperature of PAAm/IL-X was above 220 °C. In addition, the poly(3,4-ethylenedioxythiophene/carbon cloth (PEDOT/CC) electrode prepared by electroplating method exhibits excellent electrochemical performance. The specific capacitance can reach 157.8 F g−1, and the capacitance retention rate is 93% after 3000 GCD. All-solid-state supercapacitor (ASSC-X) is assembled using PAAm/IL-X electrolyte and PEDOT/CC electrodes. The energy density of ASSC-X can reach 14.22 Wh kg−1 satisfying the require of energy density for commercial devices. Interestingly, its capacitance performance of the device ASSC-X was increased by 5% at 90 °C. These high electrochemical properties indicate the potential of PAAm/IL-X as an electrolyte/separator for safe SCs.