Direct carbon fuel cell model using biocharge fuel

Direct carbon fuel cells are the systems operating at high temperatures, using solid carbon as fuel, and converting chemical energy in carbon into the electricity by electrochemical reactions. Fuel usage can be 100% due to the different phases of the fuel and the formed product gas. In this study, the performance of the fuel cell using biomass derived biochar as renewable, clean and alternative carbon was determined by modeling with Matlab programe. The effects of cell temperature, conductivity, density and size of carbon on fuel cell voltage were predicted by this modeling. Three main losses that affect fuel cell performance were evaluated. Activation losses due to electrochemical reaction, ohmic losses due to ionic and electronic conduction and concentration losses due to mass transport. In this study, all polarization losses studied were highly dependent on temperature. Activation and concentration losses in the cathode electrode were smaller than in the anode electrode. The biggest factor that reduces fuel cell performance is resistance losses. The electrical conductivity of the fuel and electrolyte used affects ohmic losses. The similar performance values were determined with graphite system when high electrical conductivity of the biochar used. The fuel cell voltage was found by subtracting polarization losses from the maximum voltage. The power density of 170-190 〖W/m〗^2 was obtained between 0.2-0.3 volts in the fuel cell where high conductivity biochar is used as fuel.