Exceptional power density and stability at intermediate temperatures in protonic ceramic fuel cells

Authors: Sihyuk Choi, Chris J. Kucharczyk, Yangang Liang, Xiaohang Zhang, Ichiro Takeuchi, Ho-Il Ji & Sossina M. Haile

 
DOI: https://doi.org/10.1038/s41560-017-0085-9
 
Instrument(s) Used: SP-300
 
Abstract

Over the past several years, important strides have been made in demonstrating protonic ceramic fuel cells (PCFCs). Such fuel cells offer the potential of environmentally sustainable and cost-effective electric power generation. However, their power outputs have lagged behind predictions based on their high electrolyte conductivities. Here we overcome PCFC performance and stability challenges by employing a high-activity cathode, PrBa_0.5Sr_0.5Co_1.5Fe_0.5O_5+δ (PBSCF), in combination with a chemically stable electrolyte, BaZr_0.4Ce_0.4Y_0.1Yb_0.1O₃ (BZCYYb4411). We deposit a thin dense interlayer film of the cathode material onto the electrolyte surface to mitigate contact resistance, an approach which is made possible by the proton permeability of PBSCF. The peak power densities of the resulting fuel cells exceed 500 mW cm⁻² at 500 °C, while also offering exceptional, long-term stability under CO₂.