Rechargeable thin film batteries of polypyrrole and polyaniline

Thin films of polypyrrole (PPy) and polyaniline (PANi) were electrochemically deposited on stainless steel substrate under potentiostatic control. Secondary batteries were assembled using these polymers as active electrode materials and propylene carbonate (PC) solutions of tetraethyl ammonium perchlorate (TEAP) as the electrolyte. In repeated charge and discharge tests, all the PANi cells performed better than the PPy-PANi cells in voltage characteristics, recyclability, charge retention and coulombic efficiency. There appears to be an optimum charging current for the polymer cells and charging the cells at rates notably different from the optimum value reduced the cell performance substantially.