Asked by: Dileep Bagnall and Anna Daca, via email
In the UK, the most widely recycled battery is the lead-acid type that we use in our cars. These are broken apart in a hammer mill, the sulphuric acid drained off, and the lead and plastic separated in a water bath. Once collected, these are melted and used to form new batteries, while the acid is converted into industrial chemicals or water.
A similar mechanical separation process is used to extract and reuse the zinc, manganese, steel and other components from alkaline batteries (such as AA and AAA).
On the other hand, current methods for recycling lithium batteries are inefficient – it’s cheaper to make new batteries than recover the lithium and cobalt from old ones. This is expected to change with the growing popularity of electric vehicles, which will help to fuel new research into lithium battery recycling methods.
Subscribe to BBC Science Focus Magazine for fascinating new Q&As every month and follow @sciencefocusQA on Twitter for your daily dose of fun facts.