平板型固体氧化物燃料电池内温度分布规律

Temperature Distribution in Planer Solid Oxide Fuel Cell

固体氧化物燃料电池(solid oxide fuel cell,SOFC)内温度梯度引起的热应力是制约其寿命的关键问题之一。针对传统SOFC温度分布测量实验中电炉对实验结果的影响,提出了采用对测试电池保温的方法,给电池提供近似绝热的工作环境,以便将实验结果拓展到实际电堆中。采用该方法,通过实验研究了平板型SOFC单电池内温度分布规律,实验结果表明:电池保温可有效降低电池与电炉间的换热,24 A放电时,电池内最大温度为782℃,比炉膛温度高32℃,证明电池保温可有效降低电炉的影响;当电流为18 A、24 A和30 A时,电池内最大温度分别为777℃、782℃和796℃,但最大温差均为5℃左右;电池内温度梯度受进气的冷却作用影响较大,但其影响范围较小,因此在电池气体入口局部会产生较大的温差,影响电池的运行安全性。

Thermal stress induced by temperature gradient in solid oxide fuel cell(SOFC)is one of the key problems restricting its life.In view of the influence of the electric furnace on the experimental results in the traditional SOFC temperature distribution measurement experiment,this paper proposes a method of insulating the test cell to provide an approximately adiabatic working environment for the cell,so as to expand the experimental results to the actual stack.Using this method,the temperature distribution law in the flat SOFC single cell was experimentally studied.The experimental results show that the cell insulation can effectively reduce the heat exchange between the cell and the electric furnace.At 24 A discharge,the maximum temperature in the cell is 782℃,32℃higher than that of the furnace,which proves that cell insulation can effectively reduce the influence of the electric furnace;when the discharge current is set at 18 A,24 A and 30 A,the maximum temperature in the cell is 777℃,782℃and 796℃respectively,but all the maximum temperature differences are about 5℃;the temperature gradient in the cell is greatly affected by the cooling effect of the intake air,but its influence range is small.Therefore,a large temperature difference will be generated locally at the gas inlet of the cell,which will affect the operational safety of the cell.