The Powergorilla is a lithium-polymer battery, as found in most laptops and portable electronic devices, all sealed up in a hard case with rubber protection.

Thanks to advances in processor efficiency, the latest generation of laptops run not only cooler, but importantly longer than ever before. But in nearly every example we test at PC Advisor, actual run time is still not enough for the real world. Until the efficiency trend advances towards a full day's working away from the mains, there will still be a need to carry a spare battery or a power charger with you everywhere - assuming, that is, that you even have access to mains power.

One solution to make up for laptop manufacturers' widespread shortfall in allowing respectable battery lives is an external battery pack, such as the Powertraveller Powergorilla. This is a lithium polymer battery, as found in most laptops and portable electronic devices, all sealed up in a hard case with rubber protection.

It has two power ports on the back, one for connection to the Powergorilla's own charger unit, the other to connect to your notebook computer. And between these lies a USB port, for powering USB devices such as iPods.

Also included in the Powergorilla package is a set of Gorilla Nuts - adaptor pins for a variety of laptop models, and Monkey Nuts, adaptors which help connection to digital cameras and mobile phones. A neoprene zip case is included for the main unit to keep it clean when carried around in a bag.

After finding the correct power tip for your device, you just need to set voltage output level from the single press button next to a blue backlit LCD display. Choices here are 16V, 19V or 24V. The Powergorilla's display also gives a graphical indication of remaining battery life.

We tested the Powergorilla with an Apple MacBook Pro, with the help of a MagSafe adaptor supplied by Powertraveller. This is actually an Apple airline flight adaptor plus a car lighter adaptor, and the resulting string of cables between Mac and Gorilla enabled an additional three hours and five minutes productivity, over the notebook's normal 3.5 hours battery life under active use.

Unfortunately the Powergorilla could not actually charge a flat MacBook battery even when it was itself mains-connected, but it could provide enough power to continue use and keep the notebook up and running.

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Powertraveller Powergorilla [PC]: Specs

  • Lithium polymer rechargeable battery
  • 21000mAh capacity
  • international mains power adaptors
  • 8 x male/7 x female notebook connectors
  • connectors for Nokia, Motorola V66, Samsung E900, LG Chocolate and Sony Ericsson phones
  • DC4.0 connector for Sony PSP
  • output capacity 21000mAh in 5V mode, 6500mAh in 16V, 5500mAh in 19V, 4200mAh in 24V
  • 220x130x15mm
  • 639g
  • Lithium polymer rechargeable battery
  • 21000mAh capacity
  • international mains power adaptors
  • 8 x male/7 x female notebook connectors
  • connectors for Nokia, Motorola V66, Samsung E900, LG Chocolate and Sony Ericsson phones
  • DC4.0 connector for Sony PSP
  • output capacity 21000mAh in 5V mode, 6500mAh in 16V, 5500mAh in 19V, 4200mAh in 24V
  • 220x130x15mm
  • 639g

OUR VERDICT

At just over 600g the Powergorilla is reasonably lightweight, and certainly slim enough to be slipped into a bag. But as a means to keep you and your laptop productive through an eight hour day, its limited power may still leave you wanting. A spare battery will typically be cheaper and give longer runtime. For lower power devices such as PDAs and satnav units, however, expect much longer battery-boosted times and the convenience of keepin them all running from one battery pack.

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