Research on high-precision survey of supercapacitor ESR

High-precisely measuring equivalent series resistance (ESR) is necessary to improve the performance and quality of supercapacitors and enhance efficiency of energy transformation. Based on the equivalent model of supercapacitor, using the measuring method of direct and constant current discharge voltage jump, precision of measurement was raised by larger direct and constant current; synchronous sampling reduced the requirement of constant current; affectation of contact resistance was eliminated; and error resulted from ambient temperature was reduced. After comparison experiments, the results show that ESR error is less than 0.05m Ω by measuring 350F supercapacitors. The requirement of high-precision measurement can be met.