Experimental study of DMFC based on operating parameters

The effects of the methanol flow rate,air flow rate,temperature,cathode back pressure and methanol concentration on the performance of a direct methanol fuel cell(DMFC) were studied.The results show that the fuel cell performance increases first and then decreases when the methanol flow rate is increased,i.e.,there exists an optimal methanol flow rate.The increasing air flow rate helps to exhaust the cathode water,so that the fuel cell performance is improved.Also,the fuel cell performance increases when the fuel cell temperature rises.The excessive air preheating temperature makes the cathode dehydration,thus reduces the fuel cell performance.The effect of methanol concentration on the performance of fuel cell is mainly due to the methanol permeability.There exists an optimal methanol concentration to make the fuel cell performance best.The experiments show that the cathode back pressure can effectively suppress the methanol permeation.