The Analysis on the Activation Procedure of Polymer Electrolyte Fuel Cells

Jang, Jong-Mun; Park, Gu-Gon; Sohn, Young-Jun; Yim, Sung-Dae; Kim, Chang-Soo; Yang, Tae-Hyun

doi:2011.2.3.131

J. Electrochem. Sci. Technol > Volume 2(3); 2011 > Article

Article

Journal of Electrochemical Science and Technology 2011;2(3):131-135.
DOI: https://doi.org/10.5229/JECST.2011.2.3.131

The Analysis on the Activation Procedure of Polymer Electrolyte Fuel Cells

Jong-Mun Jang, Gu-Gon Park, Young-Jun Sohn, Sung-Dae Yim, Chang-Soo Kim, Tae-Hyun Yang

Fuel Cell Research Center, Korea Institute of Energy Research;Fuel Cell Research Center, Korea Institute of Energy Research;Fuel Cell Research Center, Korea Institute of Energy Research;Fuel Cell Research Center, Korea Institute of Energy Research;Fuel Cell Research Center, Korea Institute of Energy Research;Fuel Cell Research Center, Korea Institute of Energy Research;

Abstract

It is, in general, believed that during the activation process, the proton conductivity increases due to wetting effect and the electrochemical resistance reduction, resulting in an increase in the fuel cell performance with time. However, until now, very scant information is available on the understanding of activation processes. In this study, dominant variables that effect on the performance increase of membrane electrode assemblies (MEAs) during the activation process were investigated. Wetting, pore restructuring and active metal utilization were analyzed systematically. Unexpectedly, the changes for both ohmic and reaction resistance characterized by the electrochemical impedance spectroscopy (EIS) after initial wetting process were much smaller when considering the degree of cell performance increases. However, the EIS spectra represents that the pore opening of electrode turns into gas transportable structure more easily. The increase in the performance with activation cycles was also investigated in a view of active metals. Though the particle size was grown, the number of effective active sites might be exposed more. The impurity removal and catalytic activity enhancement measured by cyclic voltammetry (CV) could be a strong evident. The results and analysis revealed that, not merely wetting of membrane but also restructuring of electrodeand catalytic activity increase are important factors for the fast and efficient activation of the polymer electrolyte fuel cells.

Key Words: Polymer electrolyte fuel cells, Activation, Electrode, Impurities, Structure