Abstract: Dynamic characteristics are very important for transportable power sources with direct methanol fuel cells. The dynamic voltage responses to variable current of a single direct methanol fuel cell were studied.With the aid of computer-controlled electronic load, cell potential dynamic responses to current loading cycle,magnitude of loading current, constant loading/rest time and slope of increasing current were investigated. Experimental results indicated that the fuel cell responded rapidly to dynamic change of current cycle. Open circuit voltage of the fuel cell under dynamic operating condition was higher than that under steady state operating condition.The slope of increasing current significantly affected the cell dynamic response.The interaction between electrochemical reactions and transient heat/mass transfer inside the fuel cell made key contribution to dynamic response of the fuel cell.

摘要： 直接甲醇燃料电池动态特性的研究对于实际应用来说非常重要.实验研究了直接甲醇单体燃料电池电流动态变化时电压的响应. 基于计算机控制的负载变化，得到了各种电流变化波形及不同的加载电流、放电/开路时间、加载斜率下的电池电压动态响应.结果表明电池电压对电流动态变换变化时的响应很迅速，动态运行时电池的开路电压要比稳态时的高，加载斜率对电池动态响应特性有重要影响. 电池内部电化学反应和传热传质瞬态变化的相互作用是电池动态响应的关键.