A spiral shaped regenerative microfluidic fuel cell with Ni-C based porous electrodes

Microchannel geometry, electrode surface area, and better fuel utilization are important aspects of the performance of a microfluidic fuel cell (MFC). In this communication, a membraneless spiral-shaped MFC fabricated with Ni as anode and C as a cathode supported over a porous filter paper substrate is presented. Vanadium oxychloride and dilute sulfuric acid solutions are used as fuel and electrolyte, respectively, in this fuel cell system. The device generates a maximum open-circuit voltage of similar to 1.2 V, while the maximum energy density and current density generated from the fuel cell are similar to 10 mW cm(-2) and similar to 51 mA cm(-2), respectively. The cumulative energy density generated from the device after five cycles are measured as similar to 200 mW after regeneration of the fuel by applying external voltage. The spiral design of the fuel cell enables improved fuel utilization, rapid diffusive transport of ions, and in-situ regeneration of the fuel. The present self-standing spiral-shaped MFC will eliminate the challenges associated with two inlet membrane-less fuel cells and has the potential to scale up for commercial application in portable energy generation.