Since last decade, hydrogen-fueled Micro-Tubular Solid Oxide Fuel Cells (MT-SOFCs)-based energy conversion technologies have attracted much attention due to their excellent ability to fast start-up, high tolerance to thermal cycling, high power density and superior mechanical strength. MT-SOFCs stacks have recently emerged as promising candidates for the development of environment-friendly power sources from fixed power generation to portable power. In this work, we present the early development of an original and efficient MT-SOFCs stack configuration for operation at the intermediate temperature regime (600 °C) based on four anode-supported NiO-GDC(Gadolinium-Doped Ceria)/GDC/LSCF(Lanthanum Strontium Cobalt Ferrite)-GDC cells in serial assembly. Cells were fabricated by extrusion method using different nanocomposite powders for anode, electrolyte and cathode synthesized by solution-combustion method. The best performance was achieved using a mixed fuel injection based on Air(500 [mL/min])/N2(400 [mL/min])/H2(100 [mL/min]) reaching a maximum power density of 0.38 [W/cm2] and open circuit voltage of 3 [V], which represents competitive performance concerning current SOFC technologies. Our four MT-SOFCs stack was successfully applied for power feeding of low-consumption electronic devices like cellphones, demonstrating its gross potential for applications in powering portable technologies.