Department News
Durability of Proton Exchange Membrane Fuel Cells
Seminar Date
2004-12-03
Author
임아주
Date
2004-12-03
Views
1923
1. 제 목 : Durability of Proton Exchange Membrane Fuel Cells
2. 연 사 : Prof. Thomas F. Fuller (Georgia Institute of Technology, Atlanta )
3. 일 시 : 2004년 12월 13일 월요일 오전 11:00 ~ 12:00
4. 장 소 : 301동 117호 세미나실
5. 내 용 :
Proton Exchange Membrane (PEM) fuels cells are being developed for transportation and stationary applications. Although the hours of operation are not high (5-8k hours), three factors make durability particularly challenging for transportation applications. First these fuel cells are expected to be used in hybrid vehicles. Consequently, we can expect many thousands of potential cycles. Second there is continuing pressure from oem’s to operate the fuel cell at higher temperatures to improve heat rejection. The higher temperature and lower humidities exacerbate membrane durability. Finally, a fuel cell in an automotive application must operate and start from temperatures well below zero. All of these areas that have lacked detailed fundamental studies into the mechanisms of chemical degradation, transport processes, and ionic conduction.
An important issue related to these membranes is their stability and durability. Polymer degradation occurs in Nafion®, even though it is considered to be highly stable. Thinning of membranes and detection of fluoride ions in product water provide direct evidence of chemical attack.[i] Degradation is believed to result from the formation of hydrogen peroxide, subsequent free-radical formation, and polymer attack, likely at residual H-containing end groups.[ii] This mechanism is strongly influenced by the water content of the membrane, permeability to oxygen and hydrogen, and the electrochemical environment. Although qualitative information is emerging, scant fundamental understanding of the mechanisms has been elucidated. The objectives are 1) to understand the mechanism of attack in perfluosulfonic acid (PFSA) membranes, 2) to develop the experimental tools to investigate the stability and durability of proton conducting membranes, 3) to correlate the structure and morphology of membranes with the chemical attack, and thus guide, by means of macroscopic and molecular level modeling, the development of new membrane materials that operate at low humidities and higher temperatures.
6. 연사약력 : Georgia Institute of Technology, Atlanta, GA (2004-present).
UTC Fuel Cells, South Windsor, CT
Director, Power Section Engineering (2002-2004)
Manager, Power Section Development (1998-2001)
Senior Engineer, Advanced Technology (1994-1997)
7. 문 의 : 기계항공공학부 민경덕 교수 (☏880-1661)
2. 연 사 : Prof. Thomas F. Fuller (Georgia Institute of Technology, Atlanta )
3. 일 시 : 2004년 12월 13일 월요일 오전 11:00 ~ 12:00
4. 장 소 : 301동 117호 세미나실
5. 내 용 :
Proton Exchange Membrane (PEM) fuels cells are being developed for transportation and stationary applications. Although the hours of operation are not high (5-8k hours), three factors make durability particularly challenging for transportation applications. First these fuel cells are expected to be used in hybrid vehicles. Consequently, we can expect many thousands of potential cycles. Second there is continuing pressure from oem’s to operate the fuel cell at higher temperatures to improve heat rejection. The higher temperature and lower humidities exacerbate membrane durability. Finally, a fuel cell in an automotive application must operate and start from temperatures well below zero. All of these areas that have lacked detailed fundamental studies into the mechanisms of chemical degradation, transport processes, and ionic conduction.
An important issue related to these membranes is their stability and durability. Polymer degradation occurs in Nafion®, even though it is considered to be highly stable. Thinning of membranes and detection of fluoride ions in product water provide direct evidence of chemical attack.[i] Degradation is believed to result from the formation of hydrogen peroxide, subsequent free-radical formation, and polymer attack, likely at residual H-containing end groups.[ii] This mechanism is strongly influenced by the water content of the membrane, permeability to oxygen and hydrogen, and the electrochemical environment. Although qualitative information is emerging, scant fundamental understanding of the mechanisms has been elucidated. The objectives are 1) to understand the mechanism of attack in perfluosulfonic acid (PFSA) membranes, 2) to develop the experimental tools to investigate the stability and durability of proton conducting membranes, 3) to correlate the structure and morphology of membranes with the chemical attack, and thus guide, by means of macroscopic and molecular level modeling, the development of new membrane materials that operate at low humidities and higher temperatures.
6. 연사약력 : Georgia Institute of Technology, Atlanta, GA (2004-present).
UTC Fuel Cells, South Windsor, CT
Director, Power Section Engineering (2002-2004)
Manager, Power Section Development (1998-2001)
Senior Engineer, Advanced Technology (1994-1997)
7. 문 의 : 기계항공공학부 민경덕 교수 (☏880-1661)
