Editing Direct methanol fuel cell (section)

{{Short description|Type of fuel cell}}
[[Image:Fuel cell NASA p48600ac.jpg|thumb|250px|right|Direct methanol fuel cell]]
'''Direct methanol fuel cells''' or '''DMFCs''' are a subcategory of [[proton-exchange membrane fuel cell]]s in which [[methanol]] is used as the fuel and a special proton-conducting polymer as the [[proton-exchange membrane|membrane]] (PEM).
Their main advantage is low temperature operation and the ease of transport of methanol, an energy-dense yet reasonably stable liquid at all environmental conditions.

Whilst the thermodynamic theoretical [[energy conversion efficiency]] of a DMFC is 97%;<ref name="thermodynamics">{{cite journal|author=Umit B. Demirci|doi=10.1016/j.jpowsour.2007.03.050|title=Review: Direct liquid-feed fuel cells: Thermodynamic and environmental concerns|year=2007|journal=Journal of Power Sources|volume=169}}</ref> as of 2014 the achievable energy conversion efficiency for operational cells attains 30%<ref>{{cite book|doi=10.1016/B978-0-12-383860-5.00004-3|chapter=4.4.7 Direct Methanol Fuel Cells|author=Ibrahim Dincer, Calin Zamfirescu|date=2014|title=Advanced Power Generation Systems}}</ref> – 40%.<ref>{{cite book|author=Keith Scott, Lei Xing|doi=10.1016/B978-0-12-386874-9.00005-1|title=Fuel Cell Engineering|chapter=3.1 Introduction|page=147|year=2012}}</ref> There is intensive research on promising approaches to increase the operational efficiency.<ref name="effincrease">{{cite journal|title=Determination of the efficiency of methanol oxidation in a direct methanol fuel cell|author=Pasha Majidi |display-authors=etal |journal=Electrochimica Acta|volume=199|date=1 May 2016}}</ref>

A more efficient version of a direct fuel cell would play a key role in the theoretical use of methanol as a general energy transport medium, in the hypothesized [[methanol economy]].