Working in their spare time, a group of Nissan engineers wanted a prototype Leaf electric car for a local motorsport event.

The engineers, from Nissan’s Innovation team at the Nissan Technical Center (NTCE) in Barcelona, Spain, worked on the car for six-months and created a Leaf with a 48-kilowatt hour battery pack good for driving 150 miles.

That’s a battery twice the size, both physically and by capacity, of the current 24-kilowatt hour battery in the Nissan Leaf S.

Codenamed “Cocoon” after the 1980s sci-fi movie, the team took the prototype car to a local racing event called ECOseries.

As you might guess from its name, this is a race that favors fuel economy and efficiency, not outright speed.

The extracurricular project paid off, the Cocoon took first place at the ECOseries race.

“It has been a great privilege to work on this project and to see our finished prototype race in the ECOseries, said Dario Fernandez, Senior Engineer at NTCE. “We all have a real passion for what we do and being able to work on prototype projects gives us the creative freedom to be as innovative and forward-thinking as we possibly can.”

SEE ALSO: 2018 Nissan Leaf Could Get Battery Options Up to 60 kWh

The volunteer Innovation team takes on a range of projects to push the boundaries of what is possible with electric vehicle technology.

Gareth Dunsmore, director of electric vehicles for Nissan Europe, pointed out that the Cocoon prototype wouldn’t reach production anytime soon. But he did mention that it’s, “a useful exercise in thinking outside the box, something our engineers and designers do on a daily basis.”

The 48-kilowatt hour Leaf may not see production, but it could pave the way for the next generation model. This is expected as soon as next year with a 60-kilowatt hour battery pack.

That would put it the league with the 200-mile range Chevrolet Bolt arriving later this year and Tesla’s Model 3, which is expected at the end of 2017.