PAPER BASED MINIATURE FUEL CELL WITH PENCIL STROKED GRAPHITE ELECTRODES

摘要

The invention demonstrates a single inlet paper-based flexible fuel cell using pencil stroked graphite electrodes that operates on self- pumping and selfbreathing mode to generate electrical energy. Unlike traditional fuel cell, the fuel and the oxidant streams enter as .a single entity and thus deviate from the fundamental requirement of side-by-side flow of the fluid streams. The mixture of fuel and the· oxidant fluids are kept in a single chamber thus further reduce the overall size of fuel cell device. The fuel and electrolyte mixture flows together in channel and eliminate the need of proton exchange membrane converting it to a membrane-less fuel cell. The pencil stroked porous graphite electrodes take oxygen from quiescent air for the oxidation of fuel to generate power in the range of 30 mW/cm2 over prolonged duration of 1000 minutes, with the consumption of very low volume of formic acid as fuel and sulfuric acid as electrolyte in premixed equal ratio. Moreover, when series or parallel combination of the present single inlet fuel cell devices is accomplished, the pencil strokes at the cathode and anode are not in equal numbers. This helps in avoiding cross-over of ions between electrodes and enhances the overall cell potential and power. Therefore, we develop a paper based miniaturized, flexible and efficient fuel cell that works for prolonged duration of time for use as an on-board power source in micro-electromechanical system (MEMS), GPS, sensors and actuators and disease diagnosis applications.