“A lot of people underestimated just how big a commitment the Leaf was from Nissan,” says Tom McCabe, a senior engineer who’s been working on the world’s best-selling electric car for the past six years.

He’s right: here is a major car manufacturer that didn’t just flirt with electric car technology with an out-there concept car at a far-flung motor show, but went out and made a full global model built on three different continents.

“It was a huge commitment to move the game on and change the conventions of the industry,” McCabe adds. “Competitors are now realising this is something that needs to be done properly. More people are following now.”

Nissan is approaching the fifth anniversary of Leaf production, and it is the sixth anniversary of the model’s appearance at the 2009 Tokyo motor show after its debut earlier that summer. At this year’s show, the next-generation Leaf is being previewed with a new concept car that also introduces autonomous technology to the model.