Research on Capacity Behavior of Supercapacitors

Based on the charging design of time series with two stages and testing study, the quantitative fitting relationship, which charging current related respectively with actual capacitance of carbon-based supercapacitor, available storage energy and charging efficiency, was analyzed. At room temperature, the quantitative relationship between actual capacitance and charging current was described by exponential function, and its related coefficient is not less than 0.99 A carbon-based supercapacitor with nominal capacitance 0.5 MF can hold better energy storage level when the charging current was less than 220 A. When beyond 220 A, the total available storage energy is decreased remarkably. These show that optimal energy storage level of supercapacitors is limited by the range of optimization charging parameters.