The Research About The Fast Start-up Of HT-PEMFC

The operating temperature of the HT-PEMFC(High Temperature Proton Exchange Membrane Fuel Cell)is 120-180?,which was developed on the traditional LT-PEMFC(Low Temperature Proton Exchange Membrane Fuel Cell).Some common problems of LT-PEMFC can be avoided in high operating temperature,such as complex water management system,low waste heat recycle efficiency and high requirement for hydrogen purity etc,so HT-PEMFC has become research focus in recent years.However,high operating temperature of HT-PEMFC leads to longer start-up time and increases the difficulty of its application in the field of new energy vehicles,so it is meaningful to explore a reasonable combined heating start-up strategies for accelerating its application in the field of new energy vehicles.Some studies have been done below:Firstly,a three-dimensional multiphase flow model of HT-PEMFC was established.According to the internal reaction mechanism of HT-PEMFC,a three-dimensional model was built in COMSOL based on multi-physical field coupling,and the meshing,model assumptions and internal control equations were described.Secondly,a test platform for fuel cell was constructed,and relevant experiments on a self-assembled HT-PEMFC were carried out,including the activation and polarization curves of fuel cell,and the correctness of the HT-PEMFC model was validatedThirdly,in order to study the start-up of HT-PEMFC,the material distribution,temperature distribution and start-up time of HT-PEMFC were simulated from two aspects of fuel cell structural and operating parameters.The effects of two parameters on the electrochemical reaction and heat and mass transfer in fuel cell were investigated.The final structural parameters are 0.1mm film thickness and 1mm channel height,and the operating parameters are 160? inlet temperature and 0.6V start-up voltage.Finally,several heating strategies were put forward and compared.It is found that heating other parts of fuel cell on the basis of air intake heating can shorten the start-up time.In addition,the strategy of accelerating the transfer and diffusion of reactants is better than increasing the catalytic activity of fuel cell in shortening the start-up time under the same heating power,which may be the research focus for the fast start-up of HT-PEMFC in the future.To sum up,it is an ideal heating strategy to start up a fuel cell with variable voltage by combining end-plate heating and inlet temperature.