I will focus on organic mixed ionic-electronic conductors (OMIECs), which are often soft polymers or polymer blends with conjugated structure. They are promising candidates for supercapacitor and battery electrodes as they have great ionic-electronic coupling property and decent capability of ion and electron transportation. Also, the fabrication could be easily scaled up using roll-to-roll printing as most OMIECs are solution processable. In specific, I will synthesize PEDOT or Polythiophene with carboxybetaine/sulfobetaine zwitterionic side chains via chemical polymerization. EIS and OECT will be applied to characterize the synthesized materials for capacitance and kinetics studies. Higher specific capacitance and charging rate are expected as the zwitterion side chain facilitates appropriate film swelling and ion transport. Copolymer strategy will be adopted to optimize the zwitterionic side chain ratio and thus balanced specific capacitance and ionic/electronic transportation. The accomplishment of the project will pave the way for OMIECs in energy storage application.