Batteries and charge storage devices based on electronically conducting polymers

Strong interest in energy generation and storage has yielded excellent progress on organic based solar cells, and there is also a strong desire for equivalent advancement in polymer-based charge storage devices such as batteries and super-capacitors. Despite extensive research on electronically conducting polymers including polypyrrole, polythiophene, and polyaniline, limitations to the maximum doping density and chemical stability had been considered a significant restriction on the development of polymer batteries. Recent work appears to show a meaningful increase in the upper bound of the maximum density from 0.5 to 1.0 electrons per monomer depending on the structure, processing, and ionic species used in charging and discharging of the polymers. Several recent examples have also implied that more stable, reversible charge-discharge cycling can be achieved in n-doped polymers. These observations suggest that the performance metrics of this class of electronically conducting polymer may ultimately reach the levels required for practical battery applications. Further efforts are essential to perfect practical large-scale electrode fabrication to move toward greater compatibility in the methods used for solar cells and those used in producing batteries. A better understanding must also be developed to elucidate the effects of molecular structure and polymer architecture on these materials.