Study on the Electrochemical Characteristics of a EGaIn Liquid Metal Electrode for Supercapacitor Applications

수퍼커패시터 응용을 위한 EGaIn 액체 금속 전극의 전기화학 특성 연구

  • Received : 2016.03.16
  • Accepted : 2016.04.30
  • Published : 2016.04.30


Recent years, supercapacitors have been attracting a growing attention as an efficient energy storage, due to their long-lifetime, device reliability, simple device structure and operation mechanism and, most importantly, high power density. Along with the increasing interest in flexible/stretchable electronics, the supercapacitors with compatible mechanical properties have been also required. A eutectic gallium-indium (EGaIn) liquid metal could be a strong candidate as a soft electrode material of the supercapacitors because of its insulating surface oxide layer for electric double layer formation. Here, we report the electrochemical study on the charging/reaction process at the interface of EGaIn liquid metal and electrolyte. Numerical fitting of the charging current curves provides the capacitance of EGaIn/insulating layer/electrolyte (${\sim}38F/m^2$). This value is two orders of magnitude higher than a capacitance of a general metal electrode/electrolyte interface.


Eutectic Gallium-indium liquid metal;Supercapacitor;Oxide layer;Electrochemistry;Electric double-layer


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Supported by : 서울과학기술대학교