Guemiza H., Nosov D.R., Alaa Eddine M., Schmidt D.F., Drockenmuller E., Shaplov A.S., Plesse C., Pham-Truong T.N., Aubert P.H.
Journal of Power Sources, vol. 682, art. no. 240381, 2026
We demonstrate the first application of dynamic ion gels (DIGs) from the coacervation of two oppositely charged poly(ionic-liquid)s in the fabrication of quasi-solid-state supercapacitor devices, able to operate at high temperature without liquid leakage. The formation of the DIG enables the spontaneous in situ release of free ionic liquid (IL) avoiding the need to boost the ionic conductivity by the addition of exogeneous IL. Remarkably, the DIG maintains its solid-like behavior at elevated temperatures, enabling safe operation across a wide temperature range (25–80 °C) without leakage. Used as quasi-solid-state electrolyte, binder, separator and ionic-conducting filler for the rGO-based electrodes, various parameters are optimized, including the use of single cationic/anionic poly(ionic-liquid), their association modes and DIG content. Combined with rGO-MWCNTs, DIG made from poly(1-butyl-3-[oxiran-2-ylmethyl]-1-imidazole-3-ium-s-ethylene oxide) bis (trifluoromethyl sulfonyl) imide and poly[(1-butyl-3-methylimidazolium 1-[3-(methacryl oyloxy)propylsulfonyl]-1-(trifluoromethane sulfonyl)imide)-r-(poly(ethyleneglycol) methyl ether methacrylate) yields optimal electrochemical performance of 27.2 F g−1 at 1 mV s−1 (at 25 °C) with device's excellent stability, maintaining 80% of capacitance after 4700 cycles and 60.1 F g−1 (at 80 °C) in open air conditions. Accordingly, the maximum energy/power densities of 17 Wh kg−1/137 W kg−1 at 25 °C and 31.4 Wh kg−1/366 W kg−1 at 80 °C are obtained.
