Energy storage systems play critical roles in modern society due to the increasing demand for electrical power supply for devices such as mobile electronic devices and electric vehicles as well as the need to provide reliable energy supply for the general household. Among them, electrochemical capacitors also called supercapacitors (SCs) is a complimentary energy storage system to batteries. SCs possess distinguished merit including superior energy density than conventional capacitors and higher power density than batteries.
The structure of a SC consists of current collector/ electrode materials/ electrolyte/ membrane/ electrode materials/current collector. To date, carbon based electrode materials have been used in commercial SC devices and has demonstrated high power density, enabling them very useful in certain areas such as high speed train and power for energy gate of air plane. However the limited energy density of carbon has restricted the application of the supercapacitors in a broader area which requires large amount of energy. Our research has been focus on development of strategies for supercapacitors with ultimate goals of achieving SCs with high energy density while maintaining their power density and cycling stability __ work include
- new electrode materials with tailored nanostructures using transition metal compounds and
- new device design by using the redox chemistry of anions of the electrolytes.