溶胶-凝胶流动相异型直接甲醇燃料电池性能研究

以掺杂石墨粉的中间相碳微球(MCMB/G)烧结管为阴极支撑体,采用浸涂工艺分别制备了扩散层和催化层并在其外表面包裹Nafion膜,制得管状异型阴极并组装成异型直接甲醇燃料电池;采用溶胶-凝胶法制备了适用于直接甲醇燃料电池的溶胶-凝胶流动相。研究了溶胶-凝胶流动相异型直接甲醇燃料电池的阻抗,考察了阴极支撑体壁厚、阴极扩散层载量、实验温度和溶胶黏度等对电池极化性能的影响。结果表明,异型电池阻抗比传统平板电池大,但活化后电池阻抗明显下降;较低的溶胶黏度和较高的工作温度有利于提高电池性能;支撑体壁厚为1.3 mm、扩散层载量为3.5 mg/cm2时的电极性能最优。

Performance of special-shaped direct methanol fuel cell with sol-gel flux phase

A special-shaped tubular cathode was prepared by using graphite-doped mesocarbon microbeads (MCMB/G) through dip coating the gas diffusion layer and catalyst layer and wrapping the sintering tube with the Nafion membrane subsequently. The sol-gel flux phase was prepared by sol-gel technology. The impedance of the special-shaped direct methanol fuel cell with sol-gel flux phase was investigated; the effects of tube wall thickness, gas diffusion layer loading, working temperature, and sol viscosity on the cell polarization performance were examined. The results showed that the impedance of the special-shaped cell was much higher than that of the traditional flat electrode ; however, an obvious decrease in impedance was observed after activation. The cell performance improved with the decrease in sol viscosity and with the increase in working temperature. The cell performs well when the wall thickness is 1.3mm and the gas diffusion layer loading is 3.5mg/cm².