被动式直接甲醇燃料电池运行温度特性

将电池阴极侧集流板和夹具合二为一,采用自制的七合一膜电极组件对被动式直接甲醇燃料电池进行测试,研究了开路电压稳定阶段、放电阶段和放电后电压稳定阶段过程中电池温度与室温之间温差的变化,以及电池恒电流放电时电流密度和甲醇溶液浓度对电池电压及温差的影响.研究表明:在开路电压稳定阶段加入燃料后,温差开始升高,低电流密度放电时,温差先升高后降低,放电结束后,温差急剧下降;相同浓度下,放电电流密度越高,温差越大;相同的放电电流密度下,温差随甲醇浓度的增大而升高.

Operating temperature characteristics of passive direct methanol fuel cells

A passive, air-breathing, liquid feed direct methanol fuel cell (DMFC) with self-made membrane electrode assembly (MEA) was investigated experimentally. A perforated current collector was also used as the cathode fixture. The transient voltage and temperature of the passive DMFC were tested at different discharging current densities and methanol concentrations. The results showed that the open circuit voltage decreased after the fuel injection, while the cell temperature increased because of methanol crossover. The temperature difference between the fuel cell and ambient at low discharging current density increased at first and then decreased continuously, and it dropped evidently after constant current discharge. While the temperature difference increased along with the discharging time at high discharging current density. The temperature difference increased with an increase in discharging current density. A higher methanol concentration led to a higher temperature difference due to much more permeated methanol.