I’ve talked about the merits of using ammonia borane several times in the past as a hydrogen-rich chemical compound that may one day be used to refuel H2 cars.
Now, a company called Cella Energy is using ammonia borane (NH3BH3) plus a process called coaxial electrospinning or electrospraying to either supply pure hydrogen to fuel cell vehicles or ICE cars that can run on H2 or to reduce emissions on fossil fuel based vehicles.
According to Cella, “The coaxial electrospinning process that Cella uses is simple and industrially scalable, it can be used to create micron scale micro-fibres or micro-beads nano-porous polymers filled with the chemical hydride. Cella believes that this technology can produce an inexpensive, compound material that be handled safely in air, operates at low pressures and temperatures and has sufficiently high hydrogen concentration and rapid desorption kinetics to be useful for transport applications.”
They go on to say, “Our current composite material uses ammonia borane NH3BH3 as the hydride and polystyrene as the polymer nano-scaffold. Ammonia borane in its normal state releases 12wt% of hydrogen at temperatures between 110°C and 150°C, but with very slow kinetics. In our materials the accessible hydrogen content is reduced to 6wt% but the temperature of operation is reduced so that it starts releasing hydrogen below 80°C and the kinetics are an order of magnitude faster.”
The hydrogen can also be used as a supplement to reduce current emissions in gasoline, diesel, JP-8, jet-fuel or kerosene. This can be done now using the current petroleum based refueling infrastructure with very little modifications.
The nano-scale beads that Cella refers to will move through the vehicle like a liquid, so it can be refueled as such as well. Once the hydrogen in the liquid is spent it can be pumped out of the vehicle and rehydrided somewhere else, recycled and used for fuel once again.
The elegance of this method is that thousands of high pressure hydrogen fueling stations will not need to be built to accommodate hydrogen cars. Slight modifications of current fueling stations will be needed only, so this solution could accelerate the introduction and acceptance of hydrogen cars on a wide scale very quickly. Cella, however is working on further improving its fuel so that widespread commercialization is possible.