Scientists in China have developed a temperature-responsive polymer for use in supercapacitors to prevent them from overheating.
Supercapacitors have high power densities that mean they are prone to self-propagating, uncontrolled temperature increases – an effect known as thermal runaway. The researchers have come up with a potential solution by using a temperature-responsive electrode made from a thermosensitive polymer loaded onto a surface of soluble-layered hydroxides.
Below 32oC, the polymer exists in a hydrophilic configuration and takes on water, which allows charge transport through the hydroxide layer. However, above 32oC, the polymer shrinks, becoming hydrophobic and inhibiting charge transfer.
Tests also showed the device was able to maintain 98 per cent of its initial capacitance after 50 days of use, demonstrating its long-term stability.