DealExtreme offers a 10400 mAh 10-cell battery pack for the Eee PC for just $50.
This battery pack is suitable for these Eee PC models:
Eee PC 700 701 701C 801 900 Series
Eee PC 2G Surf/Linux
Eee PC 2G Surf/XP (700X/RU)
Eee PC 2G Linux
Eee PC 2G Surf
Eee PC 2G Surf (256 RAM)
Eee PC 4G
Eee PC 4G Surf
Eee PC 4G Surf/Linux
Eee PC 4G Linux
Eee PC 4G XP
Eee PC 4G - X
Eee PC 4G (512 RAM)
Eee PC 4G Surf (512 RAM)
Eee PC 4G Surf (1G RAM)
Eee PC 8G
Eee PC 8G (1G RAM)
Eee PC 12G
Eee PC 12G (2G RAM)
Eee PC 20G
Eee PC 20G (1G RAM)
DealExtreme didn’t exactly stated how many hours the battery would last. So Eee PC 700 user Spode tried the battery pack & posted his findings on his site.
"Ubuntu suggested a discharge time of 6 hours and 48 minutes. Not bad at all. It’s been stuck on 100% for quite some time now without going down. In theory it should go down a percent every 4 minutes - I’ve been at least 10 and it’s still on 100%. However, Ubuntu is also showing some of the other stats incorrectly too - so maybe it is having trouble reporting full stop. I’ll have some more of a fiddle and see how long I get out of it!" "So, it seems that the battery can be a good back-up battery for your Eee PC if you don’t mind carrying an extra weight on your bag."
It is definitely not a replacement since, according to Spode it doesn’t fit exactly as the original Eee PC battery.
Spode came to the conclusion; "I'm not sure I consider this to be a replacement battery, as it is too impractical" Actually the battery is to big/heavy for real portable use.