直接碳燃料电池(DCFC)实验研究  

An Experimental Study of Direct Carbon Fuel Cells (DCFC)

作　　者：陈鸿伟[1] 王晋权[1] 高建强[1] 庞永梅[1] 

机构地区：[1]华北电力大学能源与动力工程学院,河北保定071003

出　　处：《热能动力工程》2007年第4期446-449,共4页Journal of Engineering for Thermal Energy and Power

摘　　要：直接碳燃料电池是一种高效、清洁的燃料电池技术,其原理是碳和氧气勿需气化和重整而直接通过电化学反应产生电能,效率可达80%,燃料利用率约达100%。自行组装了DCFC单体电池,工作温度为500～700℃;该电池采用熔融氢氧化物作电解质,并掺入一定量的催化剂;石墨作阳极,不锈钢作阴极,加湿氧气作氧化剂。对不同的电解质、不同的氧气流量下DCFC的输出性能进行了试验研究。结果表明,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70mL/min时,该电池的输出性能最佳,最大电流密度、功率密度分别为105mA/cm2和0.041W/cm2,开路电压达到0.74V。电流密度为45mA/cm2时,输出电压0.65V,可连续稳定运行20h。提出了热解-直接碳燃料电池联合系统,并以C10H22为例,分析了联合系统发电效率高达76.5%,表明该系统在未来集中式电厂中有很好的应用前景。Direct carbon fuel cells (DCFC) represent an effective and clean fuel-cell technology,which is based on the theory of producing electric energy directly through an electrochemical reaction of carbon and oxygen with no need for gasification and reforming.Its efficiency can be as high as 80% and fuel utilization rate can reach about 100%.A single-body cell of DCFC was assembled with its working temperature ranging from 500 to 700 ℃.The cell uses fusible hydroxide to serve as an electrolyte with a certain amount of catalyst being added.Graphite is used to serve as a positive pole and stainless steel as a negative one with moistened oxygen being added to serve as an oxidation agent.An experimental study has been performed of the output performance of DCFC by using different electrolytes and at different oxygen flow rates.The results of the study show that KOH has a better conductivity than NaOH and the cell made from KOH can operate more stably and is more favorable for cell output.When the oxygen flow rate is 70 ml/min,the cell has an optimum output performance with its maximal current and power density being 105 mA/cm2 and 0.041 W/cm2 respectively.The open-circuit voltage can reach 0.74 V.When the current density is 45 mA/cm2,the output voltage can reach 0.65 V and the cell can maintain a continuous and stable operation for 20 hours.A pyrolysis and direct carbon fuel-cell combined system is proposed and with C10H22 serving as an example,an analysis was performed of the combined system having a maximal power generation efficiency of 76.5%.This indicates that the system in question will have a brilliant application prospect in future centralized power plants.

关 键 词：直接碳燃料电池 石墨 熔融氢氧化物 开路电压 

分 类 号：TM911.4[电气工程—电力电子与电力传动]