BMW is breathing some fresh air into its three-year-old alternative flagship to improve performance, increase range, and add some style.

Revealed at the 2017 Los Angeles Auto Show, the i8's update (known in the industry as a "mid-cycle refresh") increases its battery capacity from 7.1 to 11.7 kilowatt-hours, improving the car's all-electric range from 15 to 18 miles.

But if you're buying the i8 for its electric-mode range, you may be missing the point.

DON'T MISS: Long-delayed BMW i8 Spyder plug-in hybrid due in 2018

Instead, the more robust battery exists to power an electric motor now rated at 141 horsepower, a jump of 12 hp over the previous motor.

The more powerful motor is still paired with a 1.5-liter turbocharged inline-3 combustion engine, which has been tweaked to reduce noise.

The combined system now produces a net 369 horsepower, up from 362 hp in the earlier generation.

2019 BMW i8 Roadster

2019 BMW i8 Roadster

However, the i8's drivetrain upgrades aren't the biggest news for BMW's alt-powertain i brand; the new 2009 BMW i8 Roadster is stealing the show in Tinseltown.

The production convertible arrives five years after the debut of the i8 Concept Spyder. It loses its rear seats and gains 132 pounds of heft over the coupe in the process.

Aside from its powered soft-top and lack of rear thrones, the i8 Roadster sports frameless doors, a vertical rear window, a new engine cover, and new aerodynamic cowls to better channel air to the Roadster's rear spoiler winglets.

WATCH THIS: 2015 BMW i8 Video Road Test

BMW quotes a 16-second transformation time for the Roadster's soft-top, which can be raised and lowered at speeds of up to 31 mph.

Additionally, the i8 Roadster receives a raft of changes beneath its skin to ensure performance is on par with the coupe.

Engineers gifted the convertible with a bespoke suspension and damping tune, modified its steering characteristics, firmed up its roll stabilization, and made steering more precise.

2019 BMW i8 Roadster, 2017 Los Angeles Auto Show

2019 BMW i8 Roadster, 2017 Los Angeles Auto Show

Combined with the i8's upgraded drivetrain, the Roadster sprints to 60 mph in 4.4 seconds. Coupe models achieve the feat just 0.2 seconds quicker.

The 2019 BMW i8 reaches showrooms in spring 2018. Pricing for the new Roadster is a stiff $164,295 including destination, making the soft-top plug-in hybrid the most expensive model in BMW's lineup.

The 2019 i8 Coupe starts at $148,495. All i8 models come standard with leather upholstery, heated front seats, 20-inch alloy wheels, and a head-up display for the driver.

Options are limited to a Tera World trim package ($3,700 on Coupes, $2,500 on Roadsters)—which includes, mystifyingly, a "leather engine cover"—and $6,300 laser headlights.

EDITOR'S NOTE: This article was originally published on November 30, 2017, when specifications for the new 2019 BMW i8 were announced. We have updated it with pricing and trim information released in February 2018.

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