Functionalized Graphene Based Supercapacitors

The power requirements of many devices and applications, ranging from transportation to portable telecommunications, exceed the capabilities of conventional batteries. Supercapacitors can provide such high powers due to their high charge-discharge rates and have the advantage of being stable for much longer times compared to batteries; but, they usually have low energy densities. There are two direct ways to increase the energy density of supercapacitors: increasing the specific capacitance of the active material, and increasing the operating voltage. Graphene based ultracapacitors can provide energy densities approaching to those of batteries due to the high specific capacitance and high surface area of graphene. In the proposed Phase I SBIR program, Vorbeck Materials, presently the only company that has EPA approval to commercially sell graphene-based products, will focus on production of high surface area graphene electrodes for ultracapacitor applications. The proof of concept for high energy density supercapacitors will be demonstrated by understanding the parameters that control the surface area and capacitance of graphene electrodes. In parallel, practical approaches for producing graphene electrodes will be developed as a preparation for the scale up.