ABSTRACT
The proliferation of portable electronic devices, the appeal of electrical vehicles, and a need for load leveling storage in renewable energy power grids have highlighted the need for high energy density storage with electrochemically rechargeable batteries. Among the more promising storage systems that have emerged involve utilizing Prussian blue (PB) and its analogues as cathodes materials for high capacity, rechargeable batteries and pseudocapacitors. Pseudocapacitors with surface coatings based on PB and its analogues can have either type of electrochemical profile, and can add substantial storage capacity to electrical double layer capacitors without much degradation of capacity over thousands of electrochemical cycles. The open structure of PB lattice allows for efficient discharging/charging of such devices via intercalation/de-intercalation of ions and rapid charge exchange via redox reactions. Substitution of the iron atoms in PB with another transition metal creates structures with new properties called Prussian blue analogues.
