Semiempirical thermodynamic modeling of a direct methanol fuel cell system

Abstract

Summary In this study, a thermodynamic model of an active direct methanol fuel cell (DMFC) system, which couples in‐house experimental data for the DMFC with the mass and energy balances for the system components (condenser, mixing vessel, blower, and pumps), is formed. The modeling equations are solved using the Engineering Equation Solver (EES) program. This model gives the mass fluxes and thermodynamic properties of fluids for each state, heat and work transfer between the components and their surroundings, and electrical efficiency of the system. The effect of the methanol concentration (between 0.5 and 1.25 M) and air flow rate (between 20 and 30 mL cm−2 min−1) on the net power output and electrical efficiency of the system and the condenser outlet temperature is investigated. The results essentially showed that the highest value for the electrical efficiency of the system is 23.6% when the current density, methanol concentration, and air flow rate are taken as 0.2 A cm−2, 0.75 M, and 20 mL cm−2 min−1, respectively. In addition, the air flow rate was found to be the most significant parameter affecting the condenser outlet temperature.

Methanol and proton transport through chitosan‐phosphotungstic acid membranes for direct methanol fuel cell

“…where ΔG is the change in the Gibb's free energy related to the overall cell reaction, z is the number of electrons transferred per mole of fuel, and F is the Faraday constant (96 480 C). For a DMFC, the overall cell reaction is 42 :…”

The potential of novel carbon nanocages as a carbon support for an enhanced methanol electro‐oxidation reaction in a direct methanol fuel cell

“…Various types of fuel cells can be classified according to the type of electrolyte and fuel applied to the system. 1,2 Direct methanol fuel cells (DMFCs) have long been considered an attractive and promising power source for numerous applications, such as electronic and electrical portables. [3][4][5] In DMFCs, methanol is used as a liquid fuel cell that has a high energy density (5.6 kWh/g) and is easy to handle, transfer and store, making it suitable as a portable power supply.…”

Potential of sodium alginate/titanium oxide biomembrane nanocomposite in DMFC application

“…1 In addition, the consumption of methanolas a fuel gives more advantage reduce the cost of fuel management Nomenclature: DI, deionized; DMFC, direct methanol fuel cell; DSC, differential scanning calorimetry; Ea, activation energy; FESEM, field emission scanning electron microscope; FTIR, Fourier transform infrared; GO, graphene oxide; HPA, heteropolyacids; IEC, ion exchange capacity; L, distance between the two electrodes; OCV, open circuit voltage; P, membrane diffusion permeability for methanol; PBI, polybenzimidazole; PEMFC, polymer electrolyte membrane fuel cell; PEMs, proton exchange membrane; PSSA, poly-styrene sulfonic acid; PVA, poly vinyl alcohol; PVP, poly (vinylpyrrolidone); R, resistance of the membrane; RGO, reduced graphene oxide; SA, sodium alginate; SA/TiO 2 , sodium alginate/titanium dioxide membrane; SGO, sulfonated graphene oxide; SPEEK, sulfonated poly (ether ether ketone); SPSF, sulfonated polysulfone; SW%, swelling ratio percentage; T, membrane thickness; TGA, thermal gravimetric analysis; T g , glass transition temperature; TiO 2 , titanium oxide; W, width of the membrane; WU%, water uptake percentage; XRD, X-ray diffraction system which unrequired the external storage likes hydrogen, leads the flexibility of the cells designing, the fuel is exists in liquid phase and the refilling process of fuel is quick to supply the energy continuously. [2][3][4][5][6] The membrane electrolyte assemble is the most important part of the DMFC and consists of electrodes (anodes and cathodes) that function as a centre for reactions and membranes that separate the anode and cathode; the membranes also serve as a barrier to the methanol trajectory as well as a pathway for protons, which are very important conductive agents. [7][8][9][10] Nafion membranes are currently used because of their advantages over other membranes like excellent conductivity of proton, noble chemical, and physical stability.…”