First, let’s clarify one important thing. Whether we are talking about fuel cells (FCEVs, Fuel Cell Electric Vehicle), or about batteries (BEV, Battery Electric Vehicle), we always talk about the electric drive. So bikes always spin electric motors, but the way they get the energy is different. Battery cars obtain it via a socket (wallbox, charger) from a nearby power plant, while cars with fuel cells take the power plant with them.
Own power plant – sounds interesting, doesn’t it? We can go deeper into this and deal with protons and electrons, but you just need to know that hydrogen (from the tank) and oxygen (from the air) enter the fuel cell and the result of their electrochemical reaction is electrical energy and pure water escaping through the “exhaust” of the car in the form pairs.
This fuel cell in the car usually occupies the same space in the nose as the internal combustion engine, the high-pressure hydrogen tanks (usually two or three) are then hidden in the space around the rear axle, so it wouldn’t actually be a problem to use the platform for a regular internal combustion engine car. The whole solution is relatively compact and, above all, light – the hydrogen Nexo does not lose interior space and does not weigh any more than other similarly sized SUVs (approx. 1.8 tons).
The Ioniq 6 is in a different weight category, due to the five meters of the battery pack, it hovers around the two-ton level (and rather over it). Batteries (whether standard lithium-polymer technology or lithium-iron-phosphate) are the largest, heaviest and most expensive component of battery electric cars.
But the integration of the battery also benefits the car in many ways – its size (combined with the compactness of the electric motors) makes it possible to stretch the wheelbase and with it maximize the space for the crew. The larger floor plan also improves stability on the road, the higher weight completely near the floor lowers the center of gravity, which improves driving characteristics. But at what cost, you ask…?
The price of batteries is an often discussed topic, and indeed this technology is not yet at the price level of combustion engines – the Hyundai Ioniq 6 thus starts with a price at the level of 1,159,900 crowns. However, with higher production volumes and continued technical development, this technology has the potential to drop significantly, so in a few years, a battery electric car could cost the same as a car with an internal combustion engine.
The price of fuel cells will not simply drop, because it is by its very nature a very complex device (and thus mass adoption as with BEVs is probably not imminent). High pressure tanks are also not cheap and neither are all the control electronics. So to say that with a Nexa with a price tag of 1.9 million you pay for a hydrogen drive and you get a car with it for free would be an exaggeration… but not by much.
And since this delicate and sensitive drive technology is located in the crash-endangered front of the car, you really don’t want to crash. The batteries hidden in the middle of the car and protected by a highly resistant cage have a higher chance of survival after all.
But if the impact was really big enough to damage the battery pack, it could start a fire that is very difficult to put out (but let’s face it, it would have to be such a blow that you probably wouldn’t care anyway) . Car companies and firefighters are still looking for a way to minimize these risks and speed up the fire extinguishing process, but it will still require some development.
With tanks of highly explosive hydrogen right under your butt, the situation doesn’t seem any more reassuring, but the risk of explosion is actually very low. The composite tanks are ballistic resistant and in the event of a car fire the hydrogen will be released as such, so it is not much of a threat.
From battery electric cars, their users expect simpler operation and easier maintenance. And practice confirms this, with the Ioniq you only have to go to the service once every two years and practically just to be sure – the technician will inspect it, check that it lights up and brakes, replace the cabin filter and you can drive happily again. With the Nex, you have to have it serviced every year, just like with a car with an internal combustion engine.
There is still some uncertainty surrounding battery life. As part of the warranty, the manufacturers guarantee 70% of the capacity after 8 years or 160,000 kilometers. However, early real-world data shows significantly lower battery capacity degradation values, and with decent handling, the battery (at most with some individual cell replacements) could last you the life of the car.
That will probably be more of a concern with the hydrogen Nex. The small power plant under the hood requires regular maintenance and its performance decreases over time (but no one can tell you exactly how long it will last due to the lack of data from real operation), the tanks are also not immortal – their service life is planned for 15 years and the replacement price is in the low hundreds of thousands.
And the most important thing in the end – which solution is actually greener? Let’s skip the production phase for now, because there are many rumors about the mining of raw materials for batteries (and a lot of confusion about recycling) and too little is publicly known about the production of complex fuel cells.
As far as the operation itself is concerned, battery electric cars clearly have the upper hand, because the production of electricity and its transport is a highly efficient process. In the case of hydrogen, at the beginning of the process, you have highly energy-intensive production and storage, followed by transport, further storage at a filling station and its conversion in a fuel cell into electrical energy. With each additional step, your efficiency drops by tens of percent (the fuel cell itself works with an efficiency of some 50-60%), while at the beginning of everything, electrical energy enters the process, which could be used directly to charge the battery. Anyone who has picked up a calculator can clearly see that it can never work out…
The only really essential advantage of hydrogen cars with fuel cells remains the speed of refueling – but we will talk more about that in the next part of this mini-series.