EFFECTS OF TEMPERATURE ON DIRECT CARBON FUEL CELL ANODE REACTION CHARACTERISTICS

The reaction characteristics of direct carbon fuel cell (DCFC) were investigated experimentally by controlling button cell temperature at 750 similar to 900 degrees C and carbon fuel temperature at 800-950 degrees C. The polarization curves, electrochemical impedance spectra and anode gas compositions were measured during testing. The results showed that raising the temperatures of both button cell and carbon fuel can improve the performance of DCFC significantly. By increasing the carbon fuel temperature, the gasification reaction rate of carbon fuel can be accelerated and the polarization of DCFC can be reduced. The gasification of carbon fuel was the limitation factor of DCFC performance. The ohmic resistance and the activation polarization decrease with increasing of button cell temperature. The carbon deposition has been observed after testing, which can be reduced at higher temperature according to thermal dynamic analysis. In addition, it was deduced that the disordered carbon in carbon fuel is more active from Raman spectra.