Matthew Lambourne, Main Arm
The idea of interchangeable batteries for electric cars (David Gilet, last week) is an excellent one, but there is one difficulty – those batteries weigh several hundred kilos. Not really feasible to carry a spare or two in the boot. Although there is at least one company in China that is making cars with interchangeable batteries that can be changed over in a few minutes. But machinery, probably hydraulic, is needed to handle the weight. Battery technology is improving all the time, so David’s idea may be realistic before long.