In order to charge most netbook batteries you have to make sure they’re inserted firmly in your computer and that the laptop is plugged into a wall socket. So if you have a spare battery, there’s no way to charge it up while you’re out and about using your netbook — unless you buy a spare battery charger.
A few months ago Expansys began selling clip-on chargers for the Asus Eee PC 701, 900, and 901 at relatively high prices. Now at least two stores are offering somewhat cheaper, if bulkier chargers for use with Eee PC 701 or 900 batteries.
Like the clip-on chargers, these units need to be used with the main power supplythat comes with your netbook. In other words, you can’t charge two batteries at once unless you already have an extra power adapter.
These chargers are designed to work with standard or high capacity Eee PC batteries, and prices start at about $16 US.
via Eee PC.net