Abstract:
Development of inexpensive and flexible solid polymer electrolytes (SPEs) is critically important for the
cost-effective electrochromic device (ECD) fabrication. The SPEs are also an integral part of the flexible
ECDs which are projected to boost up the ECD's usability in several unexplored areas. Here we report the
synthesis of polymethyl methacrylate (PMMA) based aprotic salt (LiClO4) containing SPEs, which are
more or less electrochemically benign in the normal ECD operational voltage window. Experiments
verified that the developed SPEs have good luminous clarity (transmittance492%), high ionic conductivity of the order of 10 4 S/cm and excellent dimensional stability, all of which are required for the
ideal ECD operations. Impedance spectroscopy showed an enhancement in the ionic conductivity and
decrease in the solid electrolyte interface (SEI) resistance with increasing salt loading. Two different
device configurations using these SPEs were fabricated and then subjected to detailed electrochemical
studies. Comprehensive analysis established long term cyclic durability of the SPEs. Prototype ECDs
fabricated using these SPEs rendered excellent optical modulation and coloration reversibility.
