( 1. 东莞新能源电子科技有限公司, 东莞 523080;
2. 清华大学 深圳研究生院, 深圳 518055;
3. 中国科学院 物理所, 北京 100080)
摘 要: 利用自制的膜电极组件和自行设计开发的模具， 组装成被动式直接甲醇燃料电池， 测量其在不同甲醇供给浓度下的放电性能。 结果表明： 随着甲醇浓度的逐渐增加， 被动式电池的放电性能先上升后下降， 在浓度为2mol/L时性能达到最佳。 对其放电行为的分析表明， 这一现象是阳极浓差极化和甲醇渗透共同作用的结果。 采用GC热导的方法， 对甲醇溶液的浓度进行标定， 结果表明只需微量样品就可以快速、 准确地测量出甲醇浓度。 采用该方法对被动式单电池在长时间放电过程中燃料腔内的甲醇浓度的变化进行了检测， 通过实验对此系统的法拉第效率进行了估算， 结果表明该被动式直接甲醇燃料电池的法拉第效率可以达到44%。
关键字: 被动式直接甲醇燃料电池； 甲醇浓度； 甲醇渗透； 气相色谱热导检测； 法拉第效率
（ 1. Dongguan Amperex Electronics Technology Co., Ltd.,
Dongguan 523080, China;
2. Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, China;
3. Institute of Physics, Chinese Academy of Sciences, Beijing 100080, China）
Abstract: A passive liquid feed direct methanol fuel cell (DMFC) was assembled with MEA and self-fabricated. The discharge performance were tested with different feed methanol concentration at room temperature. The results show that the cell discharge performance increases at the beginning then drops with the increasing methanol concentration, and reaches the optimum at 2mol/L methanol, which is caused by anode concentration polarization and methanol crossover. Attempts to character the methanol concentration were made. The results show the GC thermal conductivity method can be used to character the methanol concentration practically. Then this method was applied to detect the methanol concentration change in the fuel container during the cell's long term discharge. Rough calculation shows that Faradic efficiency of our passive cell system is about 44%.
Key words: passive DMFC; methanol concentration; methanol crossover; GC thermal conductivity; Faradic efficiency
