Batteries and Charging Times
The most common criticisms of electric vehicles are related to range anxiety and recharge times. When your gasoline car is running low on fuel, you stop at a gas station, fill up the tank, pay, and drive away. The whole process usually takes no more than five minutes.
Electric cars, on the other hand, have a shorter range and, more importantly, take a lot longer to 'refuel': it takes a Nissan Leaf about two whole days to recharge the battery from 0 per cent when plugged into a standard home socket. Thankfully, talented engineers from all around the world are working on this problem.
Fast-charging technology has been progressing rapidly over the past few years—both the overall performance and number of charging stations are steadily increasing. After all, Tesla recently unveiled their new V3 Superchargers that are able to deliver up to 250 kW; they claim that a 5-minute charge can add up to 120 km to the range of their Model 3.
Image courtesy of Unsplash.
And other companies aren’t far behind, either: Porsche and BMW are already testing even more powerful, 450 kW charger prototypes for their future EVs. Their 'FastCharger' is supposedly able to provide enough power for 100 km in just three minutes (although cars that are able to take full advantage of the system aren’t yet available).
Piëch, an electric car startup, has even more ambition. They have designed a charger and battery pack that can recharge 80 per cent of their Mark Zero car’s battery (approximately 400 km's worth) in only five minutes.
But fast charging brings with it a slew of other issues.
The first one is the effect that fast charging will have on the lifespan of the batteries themselves. The other, admittedly more problematic, one is how the electric grid will handle the massive power requirements of such chargers. Quickly filling up one Piëch Mark Zero (charging a 75 kWh pack in under 10 minutes), for instance, requires around one megawatt of power. And that number needs to be multiplied for every other car that’s also using fast charging at that particular station. So far, we don’t have any practical solutions to this problem.
There are also plenty of improvements being made in the field of battery technology itself. While we can read about 'breakthrough discoveries' in battery performance virtually every month, some of the more conservative ones seem to be slowly coming to fruition.
Take 24M for example—the company is set to deliver its first products in 2020. By removing unnecessary components and simplifying the design of their Lithium-ion batteries, they supposedly managed to increase the capacity by 15 per cent while at the same time potentially lowering manufacturing costs by reducing the volume of inactive materials needed in the construction of the battery packs. They are also working on an approach that could improve the capacity by nearly 100 per cent, but they will first need to scale down their design.
Some other concerns relating to batteries are the loss of maximum battery capacity over a car’s lifetime, a range-reduction in cold weather, and the danger of an EV catching fire.
Image courtesy of Pixabay.
While it is true that batteries degrade with age, the effect isn’t as large as one may believe. Reports from Tesla owners show that an average Tesla battery degraded less than 10 per cent after 270,000 km (although regularly using fast charging can increase that value).
Cold weather is another story. A new study found that when the interior heaters are being used, the range of an electric car can be reduced by more than 40% in a −7°C environment. It is worth noting that this number applies to short trips: once the car heats up, the effect is somewhat reduced. There is one upside to using an electric car in a cold climate though: the batteries don’t go flat during the night because of their large capacity.
As for the concerns surrounding spontaneously combusting batteries, based on Tesla’s own data they claim that their cars are 11 times less likely to catch on fire than their gas-guzzling competitors. Which, if true, makes this a non-issue.
Electric vehicles are just now starting to carve out their place in the market and engineers around the world are slowly overcoming the biggest problems that are standing in the way of mass-market EV adoption.
Even though current EVs still have plenty of drawbacks, they promise to improve on gas-powered cars in almost every way imaginable.
Will they help us save the world? Not by a long shot. But, for a person who can afford one, who doesn’t regularly take long trips, who lives in a warm climate, and who maybe even has a place to charge one overnight, switching to an electric car can represent an important and gratifying step towards a brighter future.
For more information on EVs, why not check out another article on Electronics Point: Critical Components for EV and Self-Driving Vehicles.