Demand for portable energy storage is growing with rising demand for products such as electric cars. Supercapacitors supply a higher power density and longer cycle life than a conventional battery but require porous carbon in their manufacture. A new study presents a method to create large amounts of carbon — suitable for supercapacitor manufacture — from an abundant, low-cost source: used coffee grounds.
High-value, porous carbon materials can form the basis of ‘supercapacitors’, energy storage devices with high power density, rapid energy discharge and long lifetimes. Creating porous carbon materials from biowaste is an area of current research focus; however, finding a material that is abundant, low-cost and naturally porous has remained elusive, and many biowastes yield a low amount of carbon product.