Nissan announces a new fuel cell, the SOFC, but its real revolution is not running on ethanol…

Nissan has announced today a major breakthrough in the developement of fuel cells. If you follow them with a little interest, most of the headlines about it will not surprise you. All of them, including Nissan’s press release, highlight that it can run on ethanol. Whatever: many fuel cells, from the start, do the same. They even prefer to use methanol, which produces more hydrogen with the help of a reformer, something that is also not new at all. The real ace in the hole is denounced by the name of the technology: SOFC, or Solid Oxide Fuel Cell.

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Just as a basic explanation, in case you have never heard of fuel cells, they are systems that do a sort of reverse electrolysis. Instead of putting electricity to separate oxygen and hydrogen from water molecules, it makes oxygen and hydrogen react to produce electricity, forming only water as a byproduct. This is considered the most viable option so far to power cars in a non-pollutant way. Batteries are too heavy, have a low energy density and need special elements, such as lithium, or pollutant ones, such as lead.

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This fuel cell requires heat to work, while the others work at ambient temperature, even if the oxygen and hydrogen reaction inside the cells produce heat. But the more common fuel cells, called PEFC (Polymer Electrolyte Fuel Cell), including the ones the Honda Clarity and the Toyota Mirai use, need rare metals, such as platinum, to catalyse the reaction. And this is what makes them extremely expensive in the first place. In Nissan’s SOFC, there is no need of such materials.

Nissan is not specific about how the SOFC starts to work in its researches, but it must have a pre-heating mechanism that probably deactivates a little later. The heat SOFC produces by itself is them seized not only by them, but also by the reformer. That, according to Nissan, makes the process very energy-efficient.

Another technical difference between the SOFC and the PEFC is that the former works with oxygen ions, while the latter functions by allowing only protons, from hydrogen, pass through its membrane. But there are more features that make the Nissan creation, called e-Bio Fuel Cell, a very unique proposition in the automotive industry.

 

Get the fuel tank back to business

The use of a reformer allows the Nissan SOFC to use ethanol as fuel. All others need to have an extremely high pressure tank to store hydrogen.

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Ethanol is not toxic, as methanol, and you can use it to refuel regular cars in Brazil, for example. If this fuel cell becomes commercially viable, Brazil is a candidate to test it from the start because of this characteristic.

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But it gets even better. The current ethanol used in Brazil to fuel cars has water in it, in a proportion of 5%. The ethanol used by the SOFC can have up to 45% of water, what makes it much cheaper. And using biofuels to power the SOFC does not increase the CO2 levels in the atmosphere. The plants they are made of capture the CO2 that is already present in the air.

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Lowering running costs

According to Nissan, a car with the e-Bio Fuel Cell would have similar running costs when compared to a BEV. And they are already the lowest ones when it relates to vehicles. The explanation for that is the energy efficiency of electric cars. While a petrol powered car costs ¥ 9 to run per kilometer, or US$ 0.08, an EV would charge ¥ 2.9, or US$ 0.027. The e-Bio Fuel Cell’s would be ¥ 3.1, or US$ 0.029. If that is ever confirmed, it will be pretty impressive. Especially because you will not have to read a magazine or grab a coffee waiting for your car to recharge.

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e-Bio Fuel Cell vehicles will have no size limitation, as Nissan claims current EVs have. The reasoning is that the bigger the car, the bigger, and more expensive, the battery pack has to be. And range limitations are not so severe, or much easier to overcome. While an electric car would have to have bigger batteries, or to carry them along, the e-Bio Fuel Cell would just need a bigger fuel tank.

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If Nissan is disclosing data on the e-Bio Fuel Cell now, it must already have a car running with it. And it will surely present a concept car with the system. If not a production car with the technology to compete with the Toyota Mirai. Considering the shape of the car above, it may be a Leaf or a similar vehicle. And we hope to see it very soon. It promises to be pleasant to drive and cheap to run. This is any car owner’s dream.

Gustavo Henrique Ruffo

I have been an automotive journalist since 1998 and have worked for many important Brazilian newspapers and magazines, such as the local edition of Car and Driver and Quatro Rodas, Brazilian's biggest car magazine. I have also worked for foreign websites, such as World Car Fans and won a few journalism prizes, among them three SAE Journalism Awards and the 2017 IAM RoadSmart Safety Award. I am the author of "The Traffic Cholesterol", a book about bad drivers that you can buy at Hotmart, Google Play, Amazon and Kobo.