A Single Air-Breathing Direct Ethanol Fuel Cell

Abstract

Development of fuel cell system for convenient applications such as portable electrical
supplies is necessary. An air-breathing direct ethanol fuel cell, DEFC, is proposed over a closed
air DEFC because this fuel cell does not require high pressure air feeding. Moreover, ethanol
which can be obtained from agricultural product is also used as fuel in this system. In this work,
comparisons of performances of air-breathing and closed air DEFC’s were carried out. Fuel cells
of 50 cm2 active area with Nafion 112 membrane and 0.4 mg/cm2 of Pt/C catalyst loading on

both anode and cathode sides were fabricated and experimentally tested. The results showed
that the air-breathing fuel cell, which eliminatepower consumptionby auxiliary devices,provides
slightly lower power density than the closed air one. The effects of key operating parameters
on air-breathing DEFC performance were ethanol solution concentration, anode ethanol solution
flow rate and temperatures. The testing show that the best fuel cell performance was resulted
using an ethanol solution concentration of 0.1 M, an anode ethanol flow rate of 80 ml/min, and
a temperature of 85 ⁰C. A maximum power density of 1.38 mW/cm2 and current density of
4.62 mA/cm2 at 0.3 volt are obtained.