You may have heard about proton exchange membrane fuel cells (PEMFCs) before. They can provide power for a number of different uses, including military devices, portable electronics, and automotive transportation. Making PEMFCs a more widespread option is difficult, due to length of life, fueling, and cost problems. In addition, if these membranes were to become widespread, there’s a concern there may not be enough precious metal catalyst electrodes to keep future availability high. There simply may not be enough platinum to sustain our needs.
An Alternative to PEMFC
One of the most viable alternatives to PEMFCs is anion exchange membrane fuel cells (AEMFCs), which are gaining a lot of attention as of late. With these fuel cells, an anion exchange membrane (AEM) conducts carbonate (hydroxide) anions as the current flows, giving several advantages not seen in PEMFCs. We’ll look at those below.
* The ORR (oxygen reduction reaction) is more comprehensive in an alkaline environment than in an acidic one. This may allow the use of less expensive catalysts with a higher stability in those alkaline environments.
* Many liquid fuels (such as sodium borohydride) electro-kinetics are intensified by the same alkaline environment.
* The electro-osmotic drag that is seen in ion transport acts as opposition for the liquid fuels used in AEMFCs, which means more highly concentrated fuels can be used. This is especially a bonus for portable applications.
* Flexibility in terms of fuel type and ORR choice makes it possible to discover new catalysts that may be tolerant in regard to crossover fuel. This is another way in which AEMFCs are attractive for future user.
Challenges of AEMFC
The biggest challenge to bringing AEMFC into the mainstream as a commercially viable product lies in the anion exchange membrane. The materials and the methods to make this exchange are linked to each other, the final membrane properties, and the commercial process for membrane manufacturing as it gains an even bigger following. Membranes have to meet cost, durability, and performance targets, which is a tall order.
The Future of AEM Membrane
AEM membranes have had a lot of attention on them in the last few years. Research activities have exploded and progress continues to grow. Those who were formerly looking only at PEMs are now including AEMs into that equation. The modern progress on durability and performance are making way for a world where new technology may emerge at any moment.
