Direct ethanol fuel cells for transport and stationary applications - A comprehensive review

Fuel cells are one of the most efficient means of converting chemical energy into electrical energy. The major deterrents to the commercialisation of fuel cell technologies, especially for the transport sector, are the hydrogen storage and almost non-existence of hydrogen transportation and distribution infrastructure. The utilisation of bio-fuels such as methanol and ethanol instead of hydrogen as a fuel in fuel cells, not only reduces issues with fuel transportation and storage, but can also provide a CO2 neutral power generation technology and lead to a reduction in CO2 and other pollutants. In particular bioethanol is attractive as it is non-toxic, inexpensive, renewable and readily available. Currently around 90 billion litres per annum of ethanol is produced globally. It can be produced from a range of feedstock which includes sugar-cane, wheat, corn and low grade biomass such as woodchips, bagasse, waste from agroindustries, organic fractions from municipal waste or forestry residue. These factors make ethanol, especially when used with a low emission technology such as fuel cells, attractive from both an economic and environmental perspective. This has lead to a considerable interest in developing fuel cell systems operating directly on bioethanol. In this paper various types of direct ethanol fuel cells currently under development have been reviewed with emphasis on ethanol sources and production methods, cell construction materials, operating regime, cell and stack fabrication, performance and life time issues, technology status and market applications. (C) 2015 Elsevier Ltd. All rights reserved.