Motorola has reinvented the add-on extension battery as a USB device. At the Singapore-hosted CommunicAsia 2006 event this week, it unveiled the Portable Power P970 gadget, a power pack that plugs into any device with a mini USB port either to recharge the host or provide current immediately.

The P970 is essentially a 1700mAh rechargeable battery in a curvy PEBL-like casing with a USB port on top. It weighs just 79g and measures 7.4 x 5.1 x 2.4cm. Motorola is pitching the product as an accessory for its own phones and accessories, but we'd bet it will prove handy for other gadgets that can recharge through their mini USB ports, such as phones, PDA and MP3 players.

The idea's simple: you charge up the P970 at home or work. It's then ready to be hooked up to your phone when the handset's battery runs down. Motorola said the P970 is an ideal alternative to switching batteries or carrying an AC adaptor with you - not that phone chargers weigh too much these days.

The Portable Power P970 is due to ship in Q3 in a variety of phone-friendly colours. ®