The article abstract says:
The nanosheets are ideally suited for low (down to 0 C) through high (100 C) temperature ionic-liquid-based supercapacitor applications: At 0 C and a current density of 10 A g–1, the electrode maintains a remarkable capacitance of 106 F g–1. At 20, 60, and 100 C and an extreme current density of 100 A g–1, there is excellent capacitance retention (72–92%) with the specific capacitances being 113, 144, and 142 F g–1, respectively. These characteristics favorably place the materials on a Ragone chart providing among the best power–energy characteristics (on an active mass normalized basis) ever reported for an electrochemical capacitor: At a very high power density of 20 kW kg–1 and 20, 60, and 100 C, the energy densities are 19, 34, and 40 Wh kg–1, respectively. "
Which possibly suggests that the materials are suitable for indoor use (but not in cars unless you happen to operate in a non-freezing climate) which could have some very practical applications. Solar panels are becoming attractive and I'd like a storage bank but would like to avoid batteries because of the slow charge, expense, and maintenance. A super capacitor, of course, is attractive. Off the top of my head, I don't know what the power density of this type of capacitor is relative to lead acid deep cycle batteries. Still, I smile though