The latest versions of Tesla's Model S sedan have raised the bar for battery-powered high-performance cars. Image source: Tesla Motors.
Are battery-electric cars the future of transportation?
They might be. Foolish alt-energy expert Travis Hoium argues that the technology offers lots of advantages over most alternatives, and the arguments for battery-powered vehicles get a little stronger with every advance in battery technology.
But Fool auto expert John Rosevear notes that there are still plenty of disadvantages to battery-electric vehicles, including some that might be difficult for technology to overcome.
Who's right? We've asked them to lay out the pros and cons. Have a look at their arguments and see what you think.
Travis Hoium: One big advantage electric vehicles have over conventional gasoline-powered vehicles is the ability to mold the shape of the powertrain to the vehicle's design, improving performance. Electric vehicles don't have to be designed around a large engine, which is the first thing you see when you open the hood of your car. Instead, batteries can be mounted on the floor of the vehicle, which leads to a few performance advantages inherent to all EVs.
The lower batteries are mounted, the lower the center of gravity of the EV. That's a big reason Tesla Motors' (TSLA 5.93%) Model S has built its batteries into the chassis. The Model S has a center of gravity just 17.5 inches off the ground, similar to the Ford GT, which is built for high performance, not as a sedan.
As this photo of a P85D's frame shows, much of the Tesla's mass is located in the car's floor, which gives it a low center of gravity. Image source: Tesla Motors.
Modifying batteries for performance can also give EVs the ability to distribute weight evenly, which increases performance. A lot of engineering goes into designing a car with 50/50 weight distribution, but typically only high-performance vehicles go to the lengths needed to have that distribution. Traditional sedans are heavily weighted to the front, where the engine is mounted, which is why most cars are front-wheel drive, not the optimal rear-wheel drive needed for high performance.
The third major advantage EVs have when it comes to performance is acceleration. Electric motors naturally have higher torque than traditional vehicles, which gives quick zero-to-60-mph times. Tesla's Model S, for example, can go from zero to 60 in as little as 3.1 seconds, beating BMW's 2015 M3 time of 3.8 seconds. EVs aren't going to beat any top speed records with torque alone, but unless you're on a race track, it's probably not legal to go over 75 mph anyway, so reaching 150 mph faster than the next car probably doesn't matter.
These design advantages are fundamental to EVs and will be built into vehicles in the future, like they are in the Model S. In the world of EVs, everyone is driving a sports car, and that's an exciting advantage over conventional vehicles.
John Rosevear: There's no doubt that the extreme high performance of the P85D version of Tesla's Model S sedan has opened a lot of eyes. But I think the performance advantages of battery-electric cars are a bit oversold. Sure, the P85D accelerates really quickly (getting up to about 70 or 80 miles per hour, at least) thanks to the instant-on torque from its electric motors (and the grip provided by its all-wheel-drive system, and a lot of software wizardry).
But while Travis is right that batteries give designers more flexibility around the positioning of all that weight, it's still a lot of weight: A full-boat Model S P85D weighs almost 5,000 pounds, about 300 pounds more than its closest gas-powered performance rival, Fiat Chrysler's Dodge Charger SRT Hellcat.
The Hellcat is far from a nimble lightweight, but Motor Trend still gave it the nod over the Tesla in the lateral acceleration and "figure 8" handling portions of a recent head-to-head comparison. As well-located as the battery is, the Tesla's weight disadvantage probably had a lot to do with that.
But performance is really a trivial point here: As anyone who has driven either a Model S or a Hemi-powered Dodge knows, both gas-powered and battery-electric cars can be a hoot to drive.
The real cons of battery-electric cars are still the ones that have bedeviled their proponents since the beginning: Batteries are heavy and expensive, and batteries take a long time to recharge.
Costs are coming down, but they're still high, and it still takes a lot of heavy batteries to give good range. (There's a reason that Tesla builds big, high-priced cars.)
But the recharging factor is arguably the biggest disadvantage of batteries, and it's the one that may end up limiting mass adoption of battery-powered cars. It takes hours to fully recharge an electric car, and nobody has yet found an efficient way to overcome that.
Toyota says that its fuel-cell-powered Toyota Mirai is an electric car that can be "recharged" in five minutes. But fuel cells have their own list of disadvantages, at least in the near term. Image source: Toyota
That's why Toyota (TM 1.39%) veered away from battery-electrics and made a huge bet on hydrogen fuel cells. Toyota's fuel-cell Mirai is still an electric car, but it's one that can be "recharged" (refueled with hydrogen) in about five minutes.
Toyota executives think that the recharging issue will prove to be a fatal flaw in battery-electric technology. They say that the Mirai's fuel cell is a "better battery." But fuel cells have their own set of cons: They're still extremely expensive, and the refueling infrastructure lags far behind even that of battery-electric recharging stations.
Electric cars have a lot of promise, and battery-electric technology may yet win out. But the argument for batteries over a modern, efficient internal-combustion engine isn't yet clear-cut. Both have pros and cons. And as long as internal combustion continues to have a massive infrastructure and refueling advantage, as well as a still-significant (but admittedly shrinking) cost advantage, most of us will still be hitting the gas station for a while longer.
