Clean Technology 2010
S. Risser, B. Tan, H. Castaneda, K. Spahr, M. Stasik
Battelle Memorial Institute, US
hybrid supercapacitor, cathode, power density
Cost-effective electrical storage is a critical need for enhancing current devices and enabling new devices and technologies. One of the storage types Battelle has been actively investigating is hybrid supercapacitors. Achieving high energy density in combination with high power density requires both high capacity for charge and low equivalent series resistance. Our approach combines mechanistic studies and electrochemical modeling to determine the appropriate electrode materials and architecture. The nano-sized electrode materials are obtained through the controlled synthesis and formulation of super high surface area and high conductivity metal oxides with conductive supports. The electrode architecture optimizes surface storage with the double layer capacitance process and optimizes the subsurface storage using pseudo-capacitance and intercalation. The control of both the electrode composition and architecture allows the performance of the hybrid supercapacitor to be tuned to meet specific performance and cost targets including high energy density with a high cycling lifetime or increased energy density for discharge time of one second. We will present our most recent experimental results including demonstration of energy density of more than 10 Wh/kg at power density greater than 10 kW/kg.