Hydrogen fuel cells, which could find applications from vehicles to backup power supplies, suffer from one important drawback – expense.
Current mass-produced hydrogen fuel cell catalysts employ a small amount of platinum to sustain the reaction necessary to generate electricity from hydrogen. Most importantly, platinum is non-corroding, which helps the fuel cell last a long time. The problem is that platinum is rarer and more expensive than gold. The current General Motors fuel cell uses 30g of platinum, which is better than $40,000 for the platinum alone. Still, automakers are planning on rolling out hydrogen fuel cell vehicles that will probably start at over $50,000 for a basic sedan.
Recent discoveries by researchers at the University of Copenhagen could lead to significant cost reductions by optimizing the platinum catalysts used in hydrogen fuel cells. They determined that the average fuel cell stack available on the market today generates about 1A/mg Pt [Platinum]. Platinum is used is varying ways to form a hydrogen fuel cell catalyst, particles and nanoparticles being more efficient than sheets.
At first, the researchers concluded that power output was directly related to platinum particle size and weight. They started experimenting on their own, and found that it wasn’t the amount of platinum that determined output, but the density of the platinum particles. Through various iterations in determining the optimum particle size, they had overlooked particle density. As it turns out, the key to optimum catalyst efficiency, and therefore output, was linked to the most densely-packed platinum particles.
While currently-available hydrogen fuel cell platinum catalysts average 1A/mg Pt, the research at University of Copenhagen found that, with the proper platinum density, the catalyst could generate up to 8A/mg Pt. In the real world, they estimate that it would generate 5A/mg Pt. A hydrogen fuel cell catalyst such as the General Motors one, could be reduced in cost to less than $10,000. Such a fuel cell development could significantly improve the costs associated with bringing a hydrogen fuel cell vehicle to market.
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