Development of a passive direct methanol fuel cell stack for high methanol concentration

Two‐way Operations of a DMFC with a Vapor Feed and With a Liquid Feed

“…DMFCs are classified as the active and passive types based on their system structure , , i.e., the active type use pumps and/or fans for the supply of fuel and/or air to the electrodes, while the passive type supplies them without using such equipment by diffusion, natural convection and capillary action. They are also divided into the vapor feed type and liquid feed one by the state of the methanol fuel going to the anode.…”

“…A vapor feed DMFC with a vaporizer using a type of polymer membrane or a porous plate , , is advantageous due to the very simple architecture of the methanol feeding system. It can use neat methanol , , by adjusting the structural parameters of the vaporizer and related parts , , , , i.e., thickness, porosity and/or open ratio of the plate or membrane, etc., to control the MCO. The VF‐DMFC using neat methanol ideally has almost a 20 times higher volumetric energy density of the DMFC system compared to that of the liquid feed DMFC using a 2M methanol solution based on the difference of the liquid fuel amount in the reservoir.…”

Performance of an active direct methanol fuel cell fed with neat methanol

“…Under such conditions, the humidification of air at the cathode is important to hydrate the membrane and increase the power density [7,8]. The electrode structure with PCP was applied to the anode of a 2 W passive stack and the power generation using neat methanol was successfully demonstrated [4]. Similar to the DMFC with PCP, some other types of vapor feed DMFCs, that can use high methanol concentration solutions have been reported as a passive or a semi-passive system [7,9,10].…”

Development of a direct methanol fuel cell stack fed with pure methanol

“…Tsujiguchi et al [23] designed and developed a verticalorientation passive DMFC stack consisting of eight single cells, with 1.5 Â 5.5 cm 2 active area per cell. Methanol concentrations varying from 70 wt% to 100 wt% were tested and the power densities increased with the increasing methanol concentration (20 mW cm À2 for 70 wt%, 25 mW cm À2 for 80 wt%, and 30 mW cm À2 for 90 and 100 wt%).…”