The On-line Experimental Study For Proton Exchange Membrane Fuel Cell On Different Conditions

With the continuous and rapid development of science and technology, human civilization has been suffering from the negative influence on ecological environment. Governments around the world are starting to realize the significance of environmental and energy problems on the development and crisis of the earth. Based on the situation of growing crisis of environment and energy source, people focus on cleaner energy applications in order to reduce both the consumption of oil and the emission of exhausts. Fuel cell is considered as one of the alternative new energy conversion devices which are expected to replace traditional power.In system design and structure optimization based on proton exchange membrane fuel cells(PEMFCs), much effort should be spent to understand the effects of different operation parameters on cell performance. Relying on the theoretical analysis and simulation results can not accurately evaluate the practical influence of operating conditions on fuel cell performance. Hence, a combination of theoretical and experimental is needed to study fuel cell performance.In this work, on-line experimental method is adopted to investigate the working parameters, such as back pressure, inlet humidity of anode and cathode, temperature and output voltage, on the performance of the proton exchange membrane fuel cell. Based on the self-assembled PEMFC single cell, a fuel cell test and performance monitoring system is established. The operating parameters under various working conditions are confirmed. The static polarization curves under different back pressure, inlet temperature and humidities are obtained accordingly. The trend of steady state cell performance against variable operating parameters is analyzed to gain the corresponding affecting features.When PEMFC is used as vehicle power source, the output voltage and power of fuel cell tends to change frequently by a large variation, due to the complicated and variable practical working conditions. The transient response characteristic is investigated via online observation of the changes in cell voltage and current density with the working time, the polarization characteristic at different loading time is further investigated. Since PEMFC for vehicles faces the challenges of cold start performance under low temperature environment, the influences of operation model on the cold start performance are studied based on various external loading parameters. The cold start performance of PEMFC is investigated at-3 ?.