• PROCESS AND PRODUCT TECHNOLOGY • 上一篇 下一篇
张生生a,b; 俞红梅b; 朱红b; 侯俊波b; 衣宝廉b; 明平文b
ZHANG Shengshenga,b; YU Hongmeib; ZHU Honga; HOU Junbob; YI Baolianb; MING Pingwenb
摘要: At subzero temperature, the startup capability and performance of polymer electrolyte membrane fuel cell (PEMFC) deteriorates markedly. The object of this work is to study the degradation mechanism of key components of PEMFC—membrane-electrode assembly (MEA) and seek feasible measures to avoid degradation. The effect of freeze/thaw cycles on the structure of MEA is investigated based on porosity and SEM measurement. The performance of a single cell was also tested before and after repetitious freeze/thaw cycles. The experimental results indicated that the performance of a PEMFC decreased along with the total operating time as well as the pore size distribution shifting and micro configuration changing. However, when the redundant water had been removed by gas purging, the performance of the PEMFC stack was almost resumed when it experienced again the same subzero temperature test. These results show that it is necessary to remove the water in PEMFCs to maintain stable performance under subzero temperature and gas purging is proved to be the effective operation.