Solid oxide fuel cells operating in mixed gas atmospheres (fuel and oxidant), the so-called single chamber SOFCs (SC-SOFCs), are based on the same working principle as the conventional "two-chambers" SOFCs, but the absence of sealing between the two compartments provides an easier operation. This configuration has several advantages over conventional SOFCs. Indeed, new cell geometries, stack assembly and miniaturization of cells are more easily conceivable, opening the way to new applications such as energy recovery in the exhaust gas by conversion of unburned hydrocarbons into electricity. This forwardlooking energy recovery system could be applicable to automotive vehicles as well as to plants. Yano et al. and Nagao et al. in 2008 demonstrated the feasibility of such a device by investigating a stack of 12 cells incorporated at the exit of a scooter engine. However, optimization of the system including architecture, gas mixture and materials modification may lead to enhanced performances. In this study, a gas mixture closer to real exhaust conditions has been selected. It is composed of hydrocarbons (HC: propane and propene), oxygen, carbon monoxide, carbon dioxide, hydrogen and water. Concerning the cell components, a cermet composed of nickel and the electrolyte is used as anode support and two cathode material, Ce_0.9Gd_0.1O_1.95 (GDC)materials, Pr₂NiO_4+δ (PNO) and La_0.6Sr_0.4Co_0.2Fe_0.8O_3-δ (LSCF), have been selected. Cells were prepared by tape casting of the anode and screen-printing of the electrolyte and cathode materials. Ni-GDC/GDC/LSCF-GDC cell operation has delivered a maximum OCV of 706 mV and a power density reaching 16mW.cm^-2 at 500°C with a HC content of only 1000 ppm. In the present project, cathode materials will be compared regarding the cell performances and some improvements are in progress concerning the cell microstructure.