Electrochemical Stability of PEDOT:PSS as Cathodic Binder for Li-Ion Batteries

摘要

The electrodes in Li-ion batteries consist of multiple components such as active materials, conductive additives and polymeric binder. The polymeric binder influences significantly the properties and stability of the composite electrode and the overall battery performance. We proposed the application of poly-3,4-ethylendioxythiophen: polystyrene sulfonic acid (PEDOT:PSS) poly-ion complex as a conductive binder material for cathodes in lithium ion battery. In this paper we report the electrochemical behavior and stability of PEDOT:PSS in battery electrolyte in terms of cyclic voltammetry and electrochemical impedance spectroscopy. The impedance behavior of PEDOT:PSS has been studied at different ambient temperatures and the ionic and electronic conductivities of PEDOT:PSS has been evaluated using a modified transmission line model. PEDOT:PSS shows stable behavior during multiple cycling in the operated potential range up to 4.2 V and no change in the impedance was visible after 200 cycles.