High‐Performance Protonic Ceramic Fuel Cells with 1 µm Thick Y:Ba(Ce, Zr)O 3 Electrolytes

This study demonstrates the effectiveness of using thin‐film electrolytes to enhance protonic ceramic fuel cells (PCFCs). The material tested in this study is yttrium‐doped barium cerate‐zirconate (BCZY), which is a representative electrolyte material of PCFCs. The thickness of the electrolyte membrane is as small as 1 µm and designed to minimize ohmic loss in proton transport pathways. Integration of this thin BCZY electrolyte is attempted on a multilayered anode comprised of two‐step supports with bulk nickel‐yttria stabilized zirconia cermet as a base and thin nickel‐BCZY as an anode functional layer atop the base. The compatibility of this support with the deposited thin electrolyte is able to be confirmed from the results of iterated tests. The power of the fabricated cell is greater than 1.1 W cm −2 at 600 °C, which is a record high for PCFCs and is reproducible. In this paper, the origin of this high power is discussed and improvements that could be made to cell performance are further suggested.