Swedish researchers say they have developed a new type of supercapacitor that can be charged by heat and stores 2500 times more energy than the best of currently available devices.
The supercapacitor, essentially a type of battery, was developed by Linköping University after years of experimenting with various electrolytes. It is based on cheap and perfectly safe polymers that convert heat to electricity with 100 times better efficiency than currently commercially available electrolytes.
“We still don’t know exactly why we’re getting this effect,“ said Professor Xavier Crispin, who led the research at the Laboratory for Organic Electronics at Linköping University in Sweden. “But the fact is that we can convert and store 2,500 times more energy than the best of today’s supercondensers linked to thermoelectric generators,”
The patent-pending device has the potential to revolutionise solar energy storage as it is not only extremely efficient, but also suitable for manufacturing on an industrial scale, the researchers say.
The ability of the supercapacitor to harness the thermoelectric effect and turn heat to electrical energy lies within the electrolyte, which consists of ions and conductive polymers.
When one end of the supercapacitor is subjected to heat, the small positively charged ions rush towards the cooler side while the heavy polymer chains stay at the warmer side. The ions stick to the metal electrodes on the cooler end, giving rise to an electrical charge, which can be stored in carbon nanotubes next to the metal electrodes.
The system would function well with solar power installations, storing power generated when the sun shines and there is a lot of heat available and discharging at night when it gets colder. Similarly, the supercapacitor could also store heat generated by various industrial processes or waste processing.
The research, published in the journal 'Energy Environmental Science', was funded through the Knut and Alice Wallenberg Foundation as part of the 'Tail of the Sun' research project.