Silicon Supercapacitor Powers Phones for Weeks on Single Charge. Material scientists at Vanderbilt University have developed a supercapacitor made out of silicon. Previously thought to be kind of a crazy idea, the silicon capacitor can be built into a chip — which could give cellphones weeks of life from one charge, or solar cells that produce energy with or without the sun. Pretty sweet deal.
Published in Scientific Reports, the first-ever silicon supercap stores energy by gathering ions on the surface of the porous material. Different from batteries, which work on chemical reactions, the silicon supercaps can be charged in minutes and last way longer. Silicon had been considered unsuitable for supercaps because of the way it reacts with the electrolytes that make the energy-storing ions.
“If you ask experts about making a supercapacitor out of silicon, they will tell you it is a crazy idea,” said assistant professor Cary Pint, who headed the development team at Vanderbilt. “But we’ve found an easy way to do it.”
Pint’s team coated the silicon in carbon — well, technically a few nanometers of graphene — and it stabilized the surface of the silicon, making it perfect for storing energy.
“All the things that define us in a modern environment require electricity,” said Pint. “The more that we can integrate power storage into existing materials and devices, the more compact and efficient they will become.”