The return of the battery train

This year there have been two new battery train trials operating in the UK. Great Western Railway has been running a commuter train on a fast-charging battery on a branch line in Ealing, and Hitachi have just tested a hybrid inter-city diesel with an onboard battery. It’s part of global wave of interest in batteries on the railways, with new or retrofitted trains running in France, Japan, Germany and several other places.

There’s a good chance that it’s going to be an important technology. T...