Development of a novel proton conducting fuel cell based on a Ni-YSZ support

A new proton conducting fuel cell design based on the BZCYYb electrolyte is studied in this research. In high-performance YSZ-based SOFCs, the Ni-YSZ support plays a key role in providing required electrical properties and robust mechanical behavior. In this study, this well-established Ni-YSZ support is used to maintain the proton conducting fuel cell integrity. The cell is in a Ni-YSZ (375 mu m support)/Ni-BZCYYb (20 mu m anode functional layer)/BZCYYb (10 mu m electrolyte)/LSCF-BZCYYb (25 mu m cathode) configuration. Maximum power density values of 166, 218, and 285 mW/cm(2) have been obtained at 600 degrees C, 650 degrees C, and 700 degrees C, respectively. AC impedance spectroscopy results show values of 2.17, 1.23, and 0.76 Omega.cm(2) at these temperatures where the main resistance contributor above 600 degrees C is ohmic resistance. Very fine NiO and YSZ powders were used to achieve a suitable sintering shrinkage which can enhance the electrolyte sintering. During co-sintering of the support and BZCYYb electrolyte layers, the higher shrinkage of the support layer led to compressive stress in the electrolyte, thereby enhancing its densification. The promising results of the current study show that a new generation of proton conducting fuel cells based on the chemically and mechanically robust Ni-YSZ support can be developed which can improve long-term performance and reduce fabrication costs of proton conducting fuel cells.