直接碳燃料电池性能研究

Performance research on direct carbon fuel cell

直接碳燃料电池(DCFC)勿需碳和氧气气化、重整,而直接通过电化学反应产生电能,效率可达80%,燃料的理论利用率可达100%,是一种高效、清洁的燃料电池。文章所介绍的组装DCFC单体电池,以石墨作阳极,不锈钢作阴极,加湿氧气作氧化剂,采用熔融氢氧化物作电解质,并掺入一定量的催化剂,该电池工作温度为500～700℃。对不同工作温度、不同电解质和不同氧气流量下DCFC的输出性能进行了试验研究。结果表明:随着工作温度的升高,电池输出性能有很大提高;KOH比NaOH的导电性好,电池运行更稳定,更有利于电池的输出;氧气流量为70 mL/min,温度为650℃时,该电池的输出性能最佳,最大电流密度、功率密度分别为118 mA/cm^2和0.054 W/cm^2,开路电压达到0.76V。

The Direct Carbon Fuel Cell （DCFC） is an efficient, environmental friendly technology, which employs a process by which carbon and oxygen are directly converted to electricity without the need for gasification and reforming, the thermodynamic efficiency of a DCFC is 80%, and the utilization ratio of fuel can reach 100%. Individual DCFC was assembled which operating temperature is 500-700 ℃. The cell used molten hydroxide with some catalysts as electrolyte, graphite rods as anode, stainless steel as cathode, gaseous oxygen with high water content as oxidant respectively. The performance of DCFC with different temperature, electrolyte and oxygen flow was studied. The results showed the performance of DCFC were better when the temperature increases. Comparing with sodium hydroxide, the electroconductivity of potassium hydroxide was better, the operating and performance of DCFC were more stable. The best performance of DCFC was in 70 mL/min oxygen flow and at 650 ℃, In this condition, the open cell voltage can reach 0.76 V, and the maximum current and the power densities are 118 mA/cm^2 and 0.054 W/cm^2 respectively.