BMW is a step closer to introducing a Tesla Model 3 rival. While that car won't start production until 2021, the BMW Concept i4 provides a preview of what it will be like.

The Concept i4 follows the BMW i Vision Dynamics concept of 2018, but with exterior styling and specifications likely closer to the upcoming i4 production model.

That means a car close in size to the current BMW 3 Series, but with a low roofline reminiscent of the 4 Series Gran Coupe BMW expects greater interior space than internal-combustion models with the same footprint, thanks to the packaging efficiencies of the electric powertrain.

On the inside, the Concept i4 takes a page from Tesla with a minimalist interior based around a large curved display screen. BMW said this setup will carry over to the production model.

BMW also tapped Hans Zimmer—composer of scores for movies such as Gladiator and Pirates of the Caribbean—to help create unique sounds for the Concept i4. These include sounds keyed to different driving modes, as well as the door chimes and startup sound.

The upcoming i4 production model will use BMW's fifth-generation electric powertrain technology. BMW has said the most powerful version of the i4 will develop 523 horsepower.

An 80-kilowatt-hour battery pack will provide a range of 270 miles on the EPA testing cycle, according to BMW. The pack weighs 550 kilograms (1,212 pounds), the automaker said.

BMW Concept i4

BMW Concept i4

The i4 represents a significant expansion of the BMW "i" sub-brand beyond the current i3 electric car and i8 plug-in hybrid. While those vehicles appeal to relatively small niches, the i4's four-door sedan body and longer range aim for a broader range of buyers.

The i4 name itself has been around for awhile, first appearing in 2012 on a concept car that was essentially a stretched version of the i3.

This model will start production in 2021 at BMW's Munich factory. That means internal-combustion, plug-in hybrid, and battery-electric cars, will eventually roll down the same assembly line, BMW said.

The factory will get some changes for i4 production, including new machinery in the body shop, BMW said. That will accommodate the somewhat different body structure of the i4, which incorporates the battery pack as part of the floor, according to BMW.

Meanwhile, an electric version of the BMW X3 crossover is slated to start production at the end of 2020. Dubbed iX3, that model is not slated for the United States.