This year's updated BMW i3 electric car is only just arriving at U.S. dealerships after a battery-capacity boost that gives it longer range.

But already some details of the 2018 BMW i3 have leaked out, in the form of spy photos and further rumors about more battery capacity yet.

Unlike our usual previews based on manufacturer releases, then, consider this more of an educated guess at what the 2018 i3 will look like.

SEE SPY SHOTS: 2018 BMW i3 spy shots

And bear in mind that some changes, perhaps a higher-capacity battery, may be held over to the 2019 model year for U.S. buyers.

The first changes shoppers will see are mild styling changes, part of what's known in the industry as a "mid-cycle update."

Think of those design tweaks, if you like, as the BMW i3 equivalent to the new front end on the Tesla Model S that launched in April 2016.

2017 BMW i3

2017 BMW i3

In spy shots of prototype 2018 i3 test vehicles, published by Motor Authority, the camouflage only covers the front, rear, and body sides below the window line.

The hood remains the same as on the current version, indicating that changes are most likely restricted to front and rear bumpers and light units.

The internals of the headlights appear to be revised, and the front fog light design is new as well.

DON'T MISS: 2017 BMW i3 electric car: longer-range battery, 81-mile model to stay

The rear bumper's lower section also looks to have been redesigned, with more of a resemblance to that of the BMW i8 gull-wing plug-in hybrid coupe.

But it's the rumored changes to battery capacity that will likely prove more decisive in sparking BMW i3 sales in 2018 and later.

At its 2014 launch, the all-electric i3's original battery range of 81 miles was relatively competitive.

2017 BMW i3

2017 BMW i3

With an available 33-kilowatt-hour battery option, that range rose to 114 miles in the 2017 models now starting deliveries.

The range-extended 2014 REx model, meanwhile, was rated at 72 miles of electric range plus 78 miles on gasoline, totaling 150 miles.

The 2017 update gave the BMW i3 REx an electric range of 97 miles plus 83 miles of engine range, for a total of 180 miles.

CHECK OUT: 2017 BMW i3 REx: 97-mile electric range, lower efficiency

But the electric-car landscape has changed considerably since that 2017 update was planned a couple of years ago.

Not only do the 2017 Volkswagen e-Golf and Hyundai Ioniq Electric come in at 125 and 124 miles of range, the Chevy Bolt EV trumps all of them with 238 miles.

(And at a starting price several thousand dollars lower than the BMW i3's (though marketers may sniff that no one would cross-shop a BMW and a Chevrolet).

2017 BMW i3

2017 BMW i3

The rumor mill suggests that for either the 2018 or 2019 model year, the BMW i3 will see another major battery capacity boost.

The original version had 60-amp-hour cells, while the optional pack in the 2017 model uses cells with a rating of 94 amp-hours.

Samsung is preparing to launch even higher-capacity cells, however, rated at 120 amp-hours.

READ THIS: 2015 Nissan Leaf: one year later, owner offers pros and cons

Those are likely to be the cells used in the rumored BMW i5 electric crossover utility due to launch in 2018 as a 2019 model.

But if they're also used in the 2018 (or 2019) BMW i3, they would give it a further range boost, to roughly 145 miles.

That rating might go slightly higher if there are efficiency improvements to the electrical equipment and slightly reductions in its drag coefficient from the reshaped panels.

2017 BMW i3

2017 BMW i3

Whether it will be sold as a 2018 or a 2019 model in the U.S., the updated BMW i3 electric car is likely to make its debut at the Frankfurt auto show this fall.

It is unlikely to reach U.S. dealers before January of 2018, and it might lag up to several months after that.

It could answer the question, however, whether there's a market for an electric car with a battery range somewhere between 125 and 240 miles.

Green Car Reports thanks our sources, who prefer to remain anonymous—for obvious reasons.


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