Professor Wonyoung Lee’s research team (First author, Mingi Choi, Post-doctoral researcher) at the Department of Mechanical Engineering of Sungkyunkwan University (President Dong-Ryeol Shin) announced that preservation of intrinsic properties of proton conducting electrolytes enables the fuel cell performance to remarkably be improved, resulting in world’s best-performing proton conducting fuel cell.

Proton conducting fuel cell has been considered as next-generation ceramic based fuel cell type based on its high ionic conductivity and low activation energy for ion conduction. Although proton conducting fuel cell has been expected to demonstrate the high efficiency and high performance at the low temperature, difficulties in manufacturing still has remained challenge, hindering its wide-spread uses.

The research team systematically discovered the underlying mechanism of low performance of proton conducting fuel cell than predicted, and revealed that the volatilization of components in crystal structure of electrolyte during the manufacturing process significantly affect to the grain growth and low chemical stability.

The research team proposed the breakthrough for suppressing the undesired volatilization of components, resulting in about 5-fold larger grain size than the previously reported values with prefect chemical composition inside the electrolyte.

Based on this perfectly stoichiometric electrolyte, a proton conducting fuel cell system demonstrates the world’s best performance at an operating temperature range of 500-650 °C, which greatly exceeds previously reported values.

Professor Wonyoung Lee said, “We overcame the technical challenge for manufacturing the proton conducting fuel cell. Especially, since it demonstrated the world’s best performance using non-complicated method, we believe that this technology can be readily commercialized and can open the possibilities of wide-spread utilization of fuel cell for hydrogen powered stationary power plant, contributing the renewable energy society.”

This research is supported by the mid-level research support project of the National Research Foundation (No. 2019R1A2C4070158) and the Sejong Science Fellowship support project (No. 2021R1C1C2006657).

It was published online on October 16th in Energy & Environmental Science (IF: 38.53, JCR<1%), an international academic journal in the field of energy.

[Figure 1] Correlation between chemical composition and grain growth and chemical stability of the proton conducting electrolyte manufactured by control of volatilization of composition.

[Figure 2] Effects of the chemical potential of Ba on the phase separation, grain growth, and proton conductivity as a function of the sintering temperature.