Automated high current cycling test system for supercapacitor characterisation

Most supercapacitor characterisation studies have been conducted at low current levels (typically <;5A) using Electrochemical Impedance Spectroscopy instruments while the commercial test systems deployed in the few high current studies require huge investment cost. This paper presents the development of an automated high current (up to 200A) cycling test system for supercapacitor characterisation under high current operating conditions. The system consists of a DC-DC converter, an H-bridge and a system microcontroller. It provides great flexibility in setting up various test conditions by supporting a userdefined operating voltage range (e.g. half voltage and full voltage tests), current level and number of test cycles, in both pulsed AC and constant DC modes. The functionality of this system is demonstrated through the various high current cycling tests conducted on a Maxwell 650F 2.7V supercapacitor cell reported in this paper. The electrical characteristics are analysed and discussed based on the standard Resistor-Capacitor electrical model.