BMW is expanding its i8 sports car lineup.

BMW has unveiled an updated i8 Coupe and an all-new Roadster version of the plug-in hybrid sports car at the 2017 Los Angeles auto show.

The i8 Coupe returns with similar styling to last year's model but gains new-look 20-inch wheels, a front air shutter and Coupe badging on the car's C-pillar. Inside the i8 Coupe gains an available Accaro E-Copper interior treatment, a new touchscreen display, an optional head-up display and carbon and ceramic trim options.

The i8 Roadster shares most of its exterior styling with its Coupe sibling, with the exception of its retractable soft top and double-hump rear-end treatment. The Roadster is also available with 20-inch wheels and sports Roadster badging on its C-pillars as well as on the rear of the vehicle.

The i8 Roadster is available with an option travel package that increases interior storage by 92 liters. The Roadster also features a power rear window just behind the passengers that can be operated independently of the power roof. BMW says the i8's soft top can be retracted in just 15 seconds at speeds up to 50kph.

The i8 Coupe and Roadster share a single plug-in hybrid drivetrain that has been updated for the new model year. Output for the car's three-cylinder gas engine remains unchanged at 231 horsepower, but the electric motor's output has been bumped to 143 horsepower from 131 horsepower. Total system output now stands at 374 horsepower.

Battery capacity has increased from 7.1kWh to 11.6 kWh for the new model year. As a result, the i8 Coupe can now travel up to 34 miles on battery power alone, up from 22 miles. The i8 Roadster, which weighs 132 pounds more than the i8 Coupe, can travel up to 33 miles on electric power.

Despite the extra power, the new i8 Coupe's 0-60 time remains unchanged at 4.4 seconds. The heavier i8 Roadster requires 4.6 seconds to hit 60. Both models are good for a top end of 155mph.

Both i8 models will hit the market in May 2018. Pricing for the new i8 Coupe and Roadster will be announced at a later date.

Live photos by Brian Williams.