Why Battery Electric Vehicles Have Overtaken Hydrogen Fuel Cells
While electric cars are still minuscule in number compared to fossil-fuel driven cars, they are steadily gaining ground. Since 2013, the number of electric cars has doubled, but yet the overall share is less than 4 percent. And companies like Tesla have been at the forefront in changing public perception towards electric vehicles.
According to Bloomberg, EV’s accounted for 50 percent of lithium-ion demand in 2016 to manufacture vehicle batteries. However, electrification has left out a potential alternative fuel – hydrogen, which was considered as a potential replacement to petrol and diesel until 2009.
How Do Hydrogen Fuel Cells Work?
Hydrogen fuel cells generate energy through a straightforward chemical reaction: Stored hydrogen is combined with oxygen from the air with the aid of a catalyst, producing electricity.
The devices are about twice as efficient as internal combustion engines when it comes to converting chemical energy into power, and the only emissions they produce are air and water vapour. Hydrogen is mostly sourced from natural gas.
Some cars that are hydrogen fuel-cell powered are the Toyota Mirai, Hyundai Nexo and Honda’s FCX Clarity. These are niche products, sold in limited numbers only in certain markets.
Pros & Cons of Hydrogen Fuel Cells
Hydrogen is actually quite a practical option. A battery-powered electric car takes hours to charge and can achieve a range of about 200 Kms to 300 Kms at best. A hydrogen-powered car can travel the same distance within a few minutes of refueling, like a conventional petrol or diesel car.
Charging times and the capacity of electric batteries are affected by environment conditions like temperature and moisture, while hydrogen-powered cars are immune to this.
However, storing and distributing hydrogen is an issue.
Infrastructure wise, setting up hydrogen fueling stations is a big task. First comes the storage, it is very difficult to store hydrogen for a long period of time and to compress it to a high pressure and drying it is a very complicated task. However, a breakthrough with this issue has been made by making hydrogen within the fueling station.
Hydrogen-powered cars produce more heat, requiring larger radiators to keep them cool whereas battery packs heat up less as they turn chemical energy into electric energy more efficiently.
When it comes to safety, hydrogen is highly flammable, but Toyota claims to have created a strong enough fuel cell for its Mirai that didn’t explode even when shot with a 0.50 calibre bullet.
And then there’s cost. The platinum used in making hydrogen fuel cell stacks is expensive. A kilo of platinum costs around $30,000 while a kilo of lithium carbonate (used to make lithium-ion batteries) costs $20 only.
Electric vehicles also have the convenience of charging wherever there’s electricity available, but hydrogen needs specific fuel stations.
Battery-electric vehicles and hydrogen-powered cars still have a lot of catching up to do. There are about millions of cars sold every week around the world while the highest number of electric cars sold was just over a million worldwide in 2017.