When the now popular Tesla Model S electric car was first introduced in 2012, there were no Superchargers available. Today, there are 25,000 Tesla Superchargers around the world, and with the Model S Plaid adopting a new powertrain, Tesla was able to re-design the battery to take advantage of the third-gen 250-kW Supercharger. Despite Tesla still using the 18650 form-factor cylindrical battery cells, these now have improved chemistry to deliver higher performance and durability. (This is the fourth major chemistry improvement since the first Model S.) With it newest 100-kWh battery pack, Tesla claims the Plaid can recover 187 miles of driving range in 15 minutes of charging at a V3 Supercharger. But just how realistic is that claim in practice?
First, a little background on charging an EV in general. Many factors are in play to determine the charging performance, from ambient temperature to battery temperature to state of charge to charging station type. As a result, charging rates do vary in practice. Lithium-ion batteries have a certain working temperature range, typically 40-130 degrees Fahrenheit, and the higher end of the range is typically conducive to rapid charging. For an electric car that has sat unplugged overnight or in cold weather, charging time is prolonged. In a Tesla, when a driver puts a Supercharger into the navigation as its destination, the car preconditions the battery pack for rapid charging before it reaches the plug. This helps to deliver a more consistent rapid-charging experience and eases congestion at charging sites.
The V3 Supercharger
In our testing, with a preconditioned battery pack and an ambient temperature of 71 degrees, the Tesla Model S Plaid needed 51 minutes to charge from 5 to 95 percent, which added 87 kWh. The latter figure indicates the usable battery capacity is about 97 kWh, with 3 kWh as a buffer. As shown in the charging curve, it indeed reached the 250-kW maximum V3 Supercharger rate and sustained that figure for the five minutes it took to charge from 10 to 30 percent.
In order to take advantage of peak charging rate, showing up to a Supercharger with the Model S Plaid depleted to between zero and 5 percent of its full charge is the optimal starting point. After the peak, the charging rate gradually ramped down as the pack’s state of charge increased. (Imagine people rushing into an elevator: It’s easy when the elevator is empty, but as more people get in, it takes longer to let them find space to wiggle through.) If you’re on a road trip, 60 percent is a good point to stop charging the car and continue driving until you reach the next Supercharger. The reason is, after 60 percent, the charging rate begins to dip below 2 kWh per minute, so you may as well go to the next charging site, at least from a pure time standpoint. And hey, 18 minutes of charging time is good for another bathroom break.
As for Tesla’s claim of adding 187 miles of range in 15 minutes of charging time, it is pretty dead-nuts accurate with a Model S Plaid. (At least with the standard 19-inch Tempest wheels.) However, this can only happen when you begin charging the car when it already has a low amount of juice remaining. And on a Model S Plaid with the more energy consumptive optional 21-inch wheels, you are looking at adding 167 miles of range in 15 minutes.
Tesla Model S Plaid with 21-inch Arachnid wheels
MT est range
Range: Dragstrip vs. EPA vs. MotorTrend’s Real-World Estimate
Manufacturers love to talk about their electric cars’ range to sell people on buying an EV, but in reality, range is heavily dependent on the way you drive, traffic, and weather conditions. The Model S Plaid with 21-inch wheels uses 2.5 percent of its battery to finish a quarter-mile run on a racing dragstrip, so in theory—we didn’t actually launch it repeatedly until its battery died—it has roughly 10 miles of range if used for 40 consecutive dragstrip runs. Tesla says the Model S Plaid with the 21s has an EPA-estimated 348 miles of range, and that is according to EPA’s conditions and using a mix of 55 percent highway and 45 percent city driving. See the range difference from different use cases there?
We took the Tesla Model S Plaid on separate road routes for highway (70-75 mph) and city driving, then looked for the efficiency. We drove the car four times on each route, two times with air conditioning on and set to 72 degrees, and two times with it off and only the fan on.
With the ambient temperature below an average of 75 degrees, we saw 3.43 miles/kWh for city driving and 3.14 miles/kWh on the highway. Using the same EPA highway-to-city ratio, our theoretical measured range is 318 miles.
Multiply the number with energy, and you can reveal the estimated range. For example, on a road trip, chances are you would drive mostly on a freeway or highway, so you’re looking at 305 miles of total range. However, in real life, chances are you are not driving from a fully charged pack to empty. Let’s say you recharged 72 kWh (from 5 to 80 percent): Expect about 226 miles of driving on a freeway at 70-75 mph.
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