A Study of AC Impedance Measurement for Direct Methanol Fuel Cells with Different Electrode Structures

• Main Authors: Shu-Rong Guo, 郭書榕
• Other Authors: 蘇春熺
• Format: Others
• Language: zh-TW
• Published: 2009
• Online Access: http://ndltd.ncl.edu.tw/handle/m4nz5h

碩士 === 國立臺北科技大學 === 機電整合研究所 === 97 === With the gasoline’s price and electricity rates go up, every kind of electronic products start to find other source of energy which can be alternative. Because of the Direct Methanol Fuel Cell (DMFC) can match the need of slight, small, and short, it becomes the portable electronic products’ best option. DMFC is the object of this study, by using the bipolar of different size’s mesh designed with different coating Au times and operate temperatures to replace the traditional electrode. In the experiment, it use Fuel Cell Test System and AC Impedance System to test the effects to DMFC characteristic of polarization curve and impedance with different experiment parameters, furthermore give it an analysis and comparison. Custom-made Gas-Diffusion-Electrode (GDE) and the Proton Exchange Membrane (Nafion 117) used hot embossing method in 130 ℃、10 MPa on Membrane-Electrode-Assembly (MEA) process. From the experimental results, we can find the 30 mesh electrode performance are superior to drill-type electrode in room temperature, the 30 mesh of gold-coating four minutes at 80 ℃ have the highest power density 11.23 mW/cm^2 and the largest current density 118.75 mA/cm^2. Any parts of the cell’s structure including flow-channel, electrode , catalyst and membrane would have effects on cell’s output. By using different electrode mesh count and coating Au, expect that can improve the efficiency of output.