Lee, Sang-Yeop Kim, Hyoung-Juhn Cho, EunAe Lee, Kug-Seung Lim, Tae-Hoon Hwang, In Chul Jang, Jong Hyun 2024-01-20T18:03:08Z 2024-01-20T18:03:08Z 2021-09-05 2010-12 0360-3199 https://pubs.kist.re.kr/handle/201004/130857 When the temperature of a fuel cell vehicle is repeatedly reduced to subzero temperatures volume changes by water/ice transformations and frost heave mechanism can cause microstructural changes in membrane electrode assemblies (MEA), and a resultant permanent decrease in the performance of fuel cell stacks In this study five MEAs manufactured by different methods were tested under repeated freeze-thaw (F-T) cycles between -20 degrees C and 10 degrees C, and the variations in their electrochemical and microstructural characteristics were analyzed according to the initial microstructures When the MEAs were prepared by spraying catalyst inks on polymer membranes no significant micro structural changes were observed In the case of two supplied MEAs void formations at the electrolyte/electrode interface or vertical cracks within the catalyst layers were observed after 120 F-T cycles Void formation seems to be responsible for performance degradation as a result of ohmic loss, but the effect of cracks in the catalyst layers was not confirmed In 120 F-T cycles activation overpotentials and concentration overpotentials did not increase significantly for any of the MEAs even although gradual decreases in the electrochemically active surface area of the platinum catalysts and changes in the porous structure were observed (C) 2010 Professor T Nejat Veziroglu Published by Elsevier Ltd All rights reserved English PERGAMON-ELSEVIER SCIENCE LTD MEMBRANE-ELECTRODE ASSEMBLIES FUEL-CELLS PHYSICAL DEGRADATION REPETITIVELY BROUGHT WATER REMOVAL TEMPERATURES OPERATION STARTUP MODEL Performance degradation and microstructure changes in freeze-thaw cycling for PEMFC MEAs with various initial microstructures Article 10.1016/j.ijhydene.2010.08.070 1 INTERNATIONAL JOURNAL OF HYDROGEN ENERGY, v.35, no.23, pp.12888 - 12896 INTERNATIONAL JOURNAL OF HYDROGEN ENERGY 35 23 12888 12896 scie scopus 000284743900022 2-s2.0-78049454111 Chemistry, Physical Electrochemistry Energy & Fuels Chemistry Electrochemistry Energy & Fuels Article MEMBRANE-ELECTRODE ASSEMBLIES FUEL-CELLS PHYSICAL DEGRADATION REPETITIVELY BROUGHT WATER REMOVAL TEMPERATURES OPERATION STARTUP MODEL Freeze-thaw cycle Ohmic loss Microstructure Polymer electrolyte membrane fuel cell (PEMFC) Membrane-electrode assembly (MEA)