1. Research Institute of Electrochemical EnergyDepartment of Energy and EnvironmentNational Institute of Advanced Industrial Science and Technology (AIST) 1-8-31 Midorigaoka Ikeda Osaka 563-8577 Japan
2. Department of Applied ChemistryGraduate School of EngineeringOsaka University 2-1 Yamada-oka Suita Osaka 565-0871 Japan