The humble USB port is becoming more and more useful. First came the memory card with built-in USB plug, now comes the USB-charged battery.

Moixa Energy have developed the USBCELL as an environmentally-friendly alternative to normal AA batteries. The top of one side flips up to reveal a USB connector, and the battery simply plugs into an open port.

The first batteries available are AA sized, but Moixa plans to unveil a full range standard formats, as well as phone and camera batteries.

The convenience of the USBCELL means that you don’t have to carry around a separate charger or cables, and can charge it in a game station, as well as in keyboards and monitors with USB sockets.

It takes five hours to charge one of the cells if it was fully discharged; each battery has a capacity of 1300mAH.

The USBCELL can be bought online at www.usbcell.com for £12.99 for two AA batteries.