The SOFC stack is supplied with gas through an external flow cavity and can use gaseous fuels such as hydrogen and methane. The power generation efficiency reaches 54%, and the attenuation rate is no more than 1.8% per thousand hours. It can withstand multiple thermal cycles. The electrolysis efficiency of the SOEC stack is as high as 97%, and the energy consumption per standard cubic meter of hydrogen is 2.86-3.35 kWh. There is no obvious performance attenuation after running for a thousand hours.