One of the main details that we still don’t know about the upcoming Tesla Model 3 is its charging capacity.

At least, now we know for a fact that it can Supercharge – though not at what rate – since a release candidate was spotted supercharging in California this week.

The black Model 3 release candidate spotted in Cincinnati last week was at a Supercharger station, but it wasn’t seen charging.

Now a white Model 3 was spotted at the Supercharger station in Gilroy, California, and this one was in fact charging.

Witnesses say that as soon as it pulled into the Supercharger stall, Tesla engineers pulled a cover on top of the vehicle in order for people not to see inside or see it charging.

Eugene Su posted a few pictures of the sightings on Facebook:

After charging, the Model 3 pulled away with a BMW chaser car.

There was never any doubt that the Model 3 would be able to Supercharge, but the actual charge rate is what we are most interested in. Especially since the Model 3 will be the first of Tesla’s vehicles to be equipped with the new 2170 battery cell developed by both Tesla and Panasonic.

The battery cells are believed to be one of the limiting factors of high charge rates due to risks of degradation associated with charging and discharging batteries.

But that’s not the only thing that sparked speculation about the Model 3 potentially supporting higher charge rates. Tesla’s Supercharger standard currently has a capacity of up to 145 kW, but the vehicles are capped at ~120 kW.

Tesla CEO Elon Musk suggested that the upcoming “version 3” of Tesla’s fast-charging station could have an output greater than 350 kW. If higher charge rates are coming for the charging stations, Tesla will need vehicles capable of supporting those charge rates.

Now it’s only a question of what vehicles? The Model 3 will be the first Tesla vehicle to get the new cells, but the Model S and the Model X are expected to also get the upgrade later this year when Tesla’s contract with Panasonic for the 18650 cells is concluded.

The higher charge rate could also be reserved for Tesla Semi or the company’s other bigger vehicles coming to its lineup.

We will likely know when Tesla unveils the Model 3 in July and even then, the company could hide the feature like it did for Supercharging with the Model S, which it only revealed a few months after the production launch.

We could never know until we get to actually see a charging screen at a charging station – like pictured above.

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