The drive to replace polluting petrol and diesel cars with a new breed of electric vehicles has gathered momentum in recent weeks. But there is an unanswered environmental question at the heart of the electric car movement: what on earth to do with their half-tonne lithium-ion batteries when they wear out?

Read more: https://www.theguardian.com/sustainable-business/2017/aug/10/electric-cars-big-battery-waste-problem-lithium-recycling