Tesla\u2019s V3 Supercharger, Tested
A 50 percent reduction in average charging times. Adding 75 miles of range in 5 minutes, 180 miles in 15 minutes. Twice as many Teslas through a Supercharger station per day. All big, bold promises made in Tesla’s March announcement of V3 Supercharging. Does it deliver? We took a Tesla Model 3 Performance to the first V3 Supercharger to find out.
With EVs going faster and farther than ever, the last hurdle, the final counterargument to their widespread adoption, has come down to charging time. It simply takes longer to put electricity in a battery than it does gas in a tank. Never mind that EVs can be charged at home, overnight, greatly reducing the need to stop at a public charger—time spent at the public charger continues to be a major hang-up for many potential EV buyers. Faster charging has therefore become the holy grail of the EV industry.
Tesla already has the fastest chargers available, but with major competitors announcing their own high-powered charging networks on the horizon, the California automaker rolled out its third-generation Supercharger with 250-kW peak charging power to stay ahead of the pack. Big numbers were thrown around, including charging speeds of 1,000 miles of range added per hour of charging.
Of course, all of the numbers came with conditions like “up to” and “average,” so we asked Tesla for a Model 3 Long Range Dual Motor, drained its battery down to 10 percent, downloaded the latest V3-enabling firmware, and headed over to Tesla’s first public V3 Supercharger at its Hawthorne, California, design studio.
There we discovered why Tesla says its V3 Supercharging technology is still in beta. It was not quite up to its full production spec. Our Model 3 Long Range, provided by Tesla, was unable to install the firmware update, precluding us from performing our test. Thinking ahead, Tesla had a Model 3 Long Range Dual Motor Performance (which has the same battery as a Model 3 Long Range) on standby with its firmware update preinstalled. Cars swapped, we plugged in. (Counterintuitively, the V3’s cable is actually slimmer and more flexible than V1 and V2 cables thanks to its liquid cooling, which doesn’t require as much insulation.)
At first, things looked great. Indicated charging power zoomed up to 254 kW before it stabilized at 250 kW. Estimated charging time was 55 minutes. Less than 30 seconds later, though, with the battery juiced up to 16 percent, the charging rate started falling. Within minutes, it was down to 150 kW, then 130 kW, which it held until the battery reached 55 percent. From there, the charging rate slowly declined as the battery charge increased. 90 percent state of charge was reached in 41 minutes, and we eventually gave up on trying to get to 100 percent as charging time crested an hour and 15 minutes.
Is this good? Yes and no. According to other tests performed by our staff using a privately owned Model 3 Performance and a privately owned Model 3 Long Range, it was faster than V2 Supercharging, but not twice as quick, as Tesla had promoted in its blog.
In other tests, charging from 10 percent to 90 percent on a 120-kW V2 Supercharger took 51 minutes, which dropped to 50 minutes on a 150-kW-enabled V2 Supercharger with On-Route Battery Warmup enabled (a new feature that warms the battery to the optimal temperature for charging to improve charging speed by up to 25 percent, per Tesla). So 41 minutes represents a 19.6 percent improvement in charging time over V2 120 kW, which is big, but not 50 percent big. More important, it meant a real-world difference of 10 minutes (which is a lot if you’re next in line at the Supercharger).
What happened? A bit of discussion revealed the replacement car hadn’t had its On-Route Battery Warmup program running, as it had been sitting at the facility for hours. (The program activates automatically when you select a Supercharger as your destination in the car’s navigation system.) A second test was in order.
This time, we met another Tesla-supplied Model 3 Long Range at Tesla’s second V3 Supercharger at the Fremont, California, factory with Firmware 2019.20.1 installed and On-Route Battery Warmup enabled. With the range depleted to 5 percent, we plugged in and held our breath. Charging speed shot up to 250 kW but, again, only stayed there until the battery had reached 14 percent. This time, though, charging speed fell to 175 kW and stayed there until the battery reached 40 percent, at which point it went into a steady, gradual decline, dropping below 100 kW around the time the battery reached 60 percent. The recharging speed held there, briefly, before continuing its linear decline. Ninety percent state of charge was reached in 46 minutes, effectively equaling the first test, which started at a 10 percent state of charge rather than 5 percent.
Although it’s not the improvement we were hoping to see, the results were still encouraging. Higher charging speeds were maintained for longer stretches, indicating that Model 3 owners who just need to add some range to a low battery but don’t need a full charge will see faster charging times. That’s still a long way from a 50 percent drop in charging time, though.
As Tesla had granted us early access to the charger and firmware, it was aware of our charging speeds and times. After a bit of consultation, Tesla suggested there were still teething issues at play with this beta charger. A third test was arranged to see, once and for all, if V3 Supercharging could deliver on its promises.
Twenty-eight days after our initial test, we arrived back at the Hawthorne V3 Supercharger in a Tesla-supplied Model 3 Long Range on firmware 2019.20.4, its battery depleted to 5 percent and On-Route Battery Warmup enabled. This time, we were told, everything should be working at full capacity. We plugged in.
The difference was obvious immediately. The charging speed jumped up to 250 kW and stayed there until the battery had reached 28 percent. It then dipped to 170 kW and stayed there until the battery reached 45 percent, then began the same long, linear decline as the battery’s state of charge increased. 90 percent state of charge was reached in 37 minutes.
The math reveals that charging time from 5 percent to 90 percent decreased from 54 minutes on the old V2 120-kW standard to 37 minutes on the newest V3 250-kW standard, an improvement of 17 minutes. Still, that’s 31.5 percent better, closer to the “up to 50 percent” Tesla claimed. Compared to the new V2 150-kW standard, which needed 53 minutes to charge from 5 percent to 90 percent, it’s a difference of 16 minutes, or 30.2 percent faster.
Reached for comment, Tesla suggested a better metric is charging from 10 percent to 70 percent state of charge, as this better reflects how Tesla owners typically use Superchargers. This took 18 minutes, compared with 30 minutes for V2 120-kW charging and 26 minutes for V2 150-kW charging. By that metric, charging time improved by 40 percent compared with V2 120-kW charging and 30.8 percent for V2 150-kW charging. That’s even closer to Tesla’s predicted “up to 50 percent” improvement but not quite to the level of semantic differences.
Was Tesla exaggerating? Not exactly: 250 kW is, of course, more than double 120 kW, so the V3 charger is more than twice as fast as the baseline V2 charger Tesla owners have been using for the past few years. According to our results, the V3 Supercharger and Model 3 Long Range/Performance maintained that twice-as-fast rate of charging for nearly a quarter of the charging time, so if you’re low on power, it really is twice as fast.
Charging from 5 percent to 30 percent on V3 took just 5 minutes and 36 seconds compared with 12 minutes on V2 120-kW, 53.3 percent faster. Rather than bore you with a lecture on electrical engineering theory, take our word for it that the 250-kW rate of charging can’t be maintained for the entire charging period. (That’s the next holy grail.) As a result, 53.3 percent faster rate drops to 30.8 percent faster by the time you reach 70 percent state of charge and stays even at 31.5 percent faster by the time you reach 90 percent state of charge.
This isn’t unique to Tesla. All EV batteries charge more slowly as they get closer to a full charge. With fewer places for the incoming electrons to go, internal resistance increases along with potentially harmful heat, so charging must slow down to protect the battery. This is why many automakers advertise how quickly their cars charge to 80 percent; after that, charging speeds slow considerably. We should also note that all charging was done in typical California late spring/early summer weather with an ambient temperature of about 80 degrees. As always, anyone charging in cold climates will experience slower charging and lower battery capacity due to changes in battery chemistry; that’s why Tesla’s On-Route Battery Warmup is an important development.
There’s more to it, though. Tesla also claimed V3 could add 75 miles of range in 5 minutes, and that’s true—if you start with a nearly dead battery.
Using the EPA-estimated range of 310 miles for the Model 3 Long Range Dual Motor and Long Range Dual Motor Performance, the Model 3 Long Range in our third test added 78 miles of range in 5:36, charging from 5 percent to 30 percent. Adding another 62 miles, taking the indicated state of charge from 30 percent to 50 percent, took an additional 5:24, nearly as quick. Above 50 percent state of charge, though, things slow down. Adding the next 93 miles of range and reaching 80 percent state of charge took 15 minutes. Adding another 31 miles of range and reaching 90 percent state of charge took another 11 minutes on top of that.
Tesla also claimed a V3 Supercharger could add 180 miles of range in 15 minutes, and in our test, it did. Here again, gaining range that quickly requires starting with a nearly dead battery. If your battery is closer to 50 percent than it is to zero, it’s going to charge a bit slower.
Does this mean Tesla won’t be able to double the number of cars passing through Supercharger stations? Not necessarily. As noted in its blog, Tesla predicts average charging times at V3 Superchargers to drop to 15 minutes.
This is possible because Tesla owners don’t typically charge their cars to 100 percent at a Supercharger. Rather, Tesla owners (and most other EV drivers) tend to add as much charge as they need to get to their next charging destination, be it home or another Supercharger (which, in some cases, can be just 100 miles away). Faster charging, especially when you’re only charging up to 80 percent or less, will move cars through Superchargers considerably more quickly as long as owners aren’t dawdling.
There’s one more real-world factor that will affect Supercharging times: power sharing, or the lack thereof, with the V3. Tesla’s V2 Superchargers split their power between two chargers, so if someone plugs into the charger next to you, your charging speed can drop by half. V3 Superchargers get 250 kW each, all the time, so how busy a Supercharger station is will have no effect on your charging speed. If the local Supercharger you frequent is especially busy, this could seriously improve your personal charging time.
Of course, everything here is accurate as of the time it was written. As we’ve seen both in the past and during this test, Tesla iterates very quickly. New firmware updates roll out regularly, and changes to mechanical components can happen on the fly. Although our results didn’t quite match Tesla’s promises, we have little doubt the company will continue to work on these beta V3 Superchargers to increase charging speed.
The first V3 Superchargers are being rolled out across North America now and will be built separately from V2 Superchargers. (Asia and Europe will start getting theirs by the end of the year). A brand new V3 Supercharger station recently opened in Las Vegas with 24 V3 chargers. Although any Tesla can plug into a V3 Supercharger, only Long Range and Performance Model 3s running the latest firmware will be able to charge at 250 kW. Standard Model 3s, as well as the Model S and Model X, will continue to charge at 150 kW, though Tesla tells us the Model S and Model X can handle up to 200-kW charging, which might be available in the future.
According to Tesla, the cost of charging will not change for V3 Superchargers compared with V2 Superchargers, and if you have lifetime free charging on your vehicle, it will be honored. V3 Superchargers will not get special signage (but the skinnier cable will be a tip-off). The difference should also be indicated in the car’s navigation system when you select a Supercharger as your destination
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