The BMW i8 might already be three years old but the German manufacturer still hasn't offered buyers a convertible option for the hybrid sports car.

Thankfully that's set to change at the upcoming Los Angeles motor show, where BMW will reportedly be showing off the long-awaited BMW i8 Roadster.

According to the latest reports, the i8 Roadster will take centre stage on the BMW stand in LA, will be introduced with a new colour – Electric Copper – and will feature a new 'square' lightweight wheel option. The electric hood will reportedly be able to be opened in 14 seconds at speeds of up to 37mph.

The latest version of the i8 will be more powerful, too – reports have suggested that the same 1.5-litre three-cylinder petrol engine found on the coupe version of the car will carry over, but the Roadster could produce upwards of 400bhp. The current i8 produces just 357bhp and 221lb ft of torque.

Gallery: 2018 BMW i8 Roadster new spy photos

Read also:

Along with more horsepower, the BMW i8 Roadster will also reportedly get double the battery power. The current 7.1kWh battery pack is rated at 23 miles of range under the New European Driving Cycle, but BMW could double that number, bringing the battery pack size to around 14kWh. The i3 is expected to get a similar update in the near future, improving from 22kWh to 43.2kWh.

A revised chassis will also be part of the new model launch, as will a number of larger updates to the infotainment system. A new generation of iDrive and an updated gear indicator will make their debut on the i8 convertible. The new BMW i8 Roadster is expected to go on sale early in 2018.