空气自呼吸式直接甲醇燃料电池的环境适应性研究

Performance of Air Breathing Direct Methanol Fuel Cell under Ambient Condition

针对空气自呼吸式(Air breathing)直接甲醇燃料电池(Direct methanol fuel cell,DMFC)阴极直接暴露在空气中的特性,重点研究了不同空气环境条件下例如湿度、温度等因素对电池性能的影响.结果表明,DMFC对环境湿度的变化并不敏感,这是由于阳极侧甲醇溶液中水的渗透使得质子交换膜和阴极一直保持相对稳定的水含量.又从可视化方法发现,反应生成的水在阴极大部分以液态形式存在,靠重力的因素排出电池,这对阴极集流板的结构设计具有重要的指导作用.此外,环境温度对电池性能具有明显的作用.环境温度为40℃时,单电池的最大功率密度接近30 mW.cm-2,是10℃时电池功率密度的3倍.

The performance of the passive DMFC was systematically investigated under an ambient condition by simulating a wide range of temperature and humidity in a high-quality environmentally controlled room. The results indicated that the performance of the passive DMFC was nearly independent of ambient humidity from 30% to 90% RH and water produced in the cathode was expelled mostly from the cell in a liquid state. Compared with the humidity, the ambient temperature has a significant effect on the performance of the passive DMFC. The power density of 30 mW· cm^-2 were obtained at 40℃, while only 10 mW · cm^-2 at 10 ℃.