Understanding
How a Polymer Exchange Membrane Fuel Cell Works
The fuel cell has garnered enormous amounts of attention in recent
years.
This device is touted as the future of the automotive industry, promising to
reduce the amount of pollution put out by commuters, as well as reduce the dependence on petroleum and
petroleum-derived fuels.
How does a fuel cell work? What does "polymer exchange membrane" mean? Unlike other
forms of fuel cell (yes, there are several types currently in use), the polymer exchange membrane fuel cell is
ideal for automotive applications.
Other types are used for stationary power generation needs, or large-scale power
generation. Still other types can be used in mobile situations, but are not very efficient.
The polymer exchange membrane fuel cell is a simple device. It consists of an anode,
a cathode, a catalyst and a proton exchange membrane. While this may sound complex, it's actually not very
complicated.
The cathode is the positive terminal of the apparatus and conducts electrons to the
catalyst. Here, these electrons combine with hydrogen ions and oxygen, forming water, which can be used to generate
additional hydrogen electrons and also forms the waste product of the fuel cell. The cathode also has channels that
help bring oxygen to the surface of the catalyst.
The anode is the negative terminal and conducts electrons from hydrogen molecules
to an electric circuit. The anode also helps distribute hydrogen over the surface of the catalyst evenly, helping
ensure proper function in the fuel cell.
The proton exchange membrane is actually an electrolyte and conducts ions with a
positive charge. These ions are used to combine with unused electrons to form water.
The proton exchange membrane must be hydrated in order to operate and is one of
the most important elements of the fuel cell.
The catalyst is used to create the reaction between hydrogen and oxygen, in
essence creating the electric charge that is supplied to the electric motor.
The catalyst is usually made of a porous material covered with platinum, though
other materials have been developed that can reduce the cost of creating a fuel cell.
All five of these elements are required for successful operation of the fuel cell.
When hydrogen gas is forced through the anode and then through the catalyst, electrons and ions are
produced.
The electrons are then channeled to the electric motor, while the ions are
combined with unused electrons to form water. This water can then be reused to obtain even more
hydrogen.
The hydrogen fuel cell may sound complex and complicated, but the principle
underlying its operation is simple.
This device has the potential to revolutionize the way in which consumers drive,
what they drive and even how they interact with their vehicles.
For instance, hydrogen fuel cell vehicles will not have an internal combustion
engine, meaning that the vehicle can be configured in any number of ways, not necessarily in the standard form that
consumers picture when they think of an automobile.
Automakers are hard at work developing hydrogen fuel cells for consumer use and it
will be only a matter of time until the benefits are felt around the globe.
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