... Chem. Phys. Energy Storage in the Emerging Era of Smart Grids 280 1.2 Nafion inorganic composite membrane During the above solutions for high-temperature operation of PEMFC, the first solution ... alt="" Energy Storage in the Emerging Era of Smart Grids 286 4.3 Diffusion coefficient of water Water transport in the Nafion membrane influences the proton transport in the membrane(Sumner, ... 1998; Inzelt, Pineri et al. 2000), so it is important to understand the transport process in the fuel cell. Water balance in the membrane depends on the interaction among the three kind of water...