Fuel cells are electrochemical devices that convert chemical energy to electrical energy without combustion. Unlike a battery, a fuel cell can continuously produce electricity for as long as fuel is supplied to it. Proton-exchange membrane fuel cells ("PEMFCs"), analogous to polymer electrolyte membrane fuel cells, are low temperature, compact fuel cells that have been developed for transport applications as well as for portable applications such as mobile phones. A PEMFC comprises an ion exchange membrane sandwiched between but in contact with an anode and a cathode. Fuel such as hydrogen gas is introduced at the anode, forming protons that pass through the membrane. An oxidant, oxygen, is introduced simultaneously at the cathode, where the spontaneous reaction takes place to produce electricity. When using pure hydrogen the cell's only by-product is water.
When considering the introduction of fuel cells into an industrial application they are conventionally viewed as a stand-alone unit that is incorporated into the structure in much the same way as a battery. To provide the power output required a prescribed number of fuel cells are stacked, housed into a unit and then incorporated into the assembled structure. Issues are reducing the cost of fuel cells and increasing their robustness. For example, the polymer membrane needs to be not only more robust but also easily replaced if it becomes damaged.
The storage of fuel, especially hydrogen, is problematic as hydrogen is inflammable and can easily escape from pressure vessels. Depending on the material the pressure vessel is made from, some materials can experience hydrogen cracking and add to fatigue / long term durability issues.
TWI's wide experience of metallic and non-metallic materials and their fabrication and performance issues makes it well placed to assist companies with the development of rugged fuel cell systems.
In addition to this TWI can carry out hydrogen testing evaluating materials in an hydrogen rich environment at elevated temperature and pressure of up to 1000bar.
For more information, please email contactus@twi.co.uk.