Development is underway for replacing battery energy storage with a super capacitor which can be charged and discharged very quickly.
Here is the latest iteration - a new way to make super capacitors out of graphene layers.
Nanotube sheets are used as electrolyte-filled electrodes of a super capacitor.
The Strathclyde engineers are also using marabu carbon to take a step beyond batteries to super capacitors.
In general, energy can be stored in a capacitor, super capacitor, or battery.
The FlashPack had an internal battery or super capacitor that could be charged in under a minute.
Some experimenters have even used super capacitors to store energy.
Eco-Drive watches use a super capacitor recharged by a solar panel hidden under the watch face.
Solar panels and lithium polymer batteries together with super capacitors provide the required power.
The energy is then stored between charging stations by onboard super capacitors.