Do you know much about batteries? I have to admit that until yesterday I didn’t know a great deal apart from the supposed benefits of lithium ion batteries over nickel metal hydride ones.

Lithium ion batteries are the ones you’ll find in your lap top or mobile phones and are generally regarded as superior to nickel hydride, being cheaper and more powerful for their size. But it’s the nickel ones you’ll still find in most hybrid cars, notably the new Toyota Prius. 

Cars like the Tesla roadster though do have lithium ion technology although this is essentially powered by masses of lap top batteries lashed together: 6831 of them to be precise. No-one doubts though that lithium ion is the way to go and if, as everyone predicts, the electrification of the car does happen, batteries will be getting a lot more crucial in the coming years.

Charles Gassenheimer is under no illusion about this. He is the CEO of a company called Ener1 - an outfit that specialises in automotive lithium ion batteries, supplying companies like Volvo in the new electric C30. It’s big business, currently worth $7 billion (£4.4 billion) to the five big players in the market, mainly for those lap tops and mobile phones.