Application of cyanide-bridged coordination polymers for electrode materials of rechargeable batteries

Development of novel host materials with enhanced ion storage ability is of particular importance in a wide range of applications, especially the electrode materials for batteries. A cyanide-bridged coordination polymer is one of the most attractive host materials, because both the ionic-diffusion channel and electron conduction path frequently coexist within the framework. For example, a cyanide-bridged perovskite-type framework, so-called Prussian blue analog (PBA), has been studied intensively for decades from the viewpoint of electrochromism. However, the electrochemical properties, i.e., electrochemical ion intercalation/extraction of PBAs can also be applied to the electrode materials of the batteries. In this chapter, the solid state electrochemistry of PBA is briefly explained. Then, the cyanide-bridged coordination polymer electrodes for the battery application are reviewed.