I am going to a trip several days later, 7 hours plane, so a large volume battery is needed.
is ther anyone who ordered such battery before? or any recommendations?

the largest battery i found is this one. 8000mAh ipega Life Battery

What do you think of this one? large enough?

any response will be the most appreciated..

I used one of these batteries for my Mac Book Pro last year when I traveled to China, an 11 hour flight. It wasn't cheap, but it does work very well.

HyperJuice External Battery for Apple MacBook, iPad, iPhone, iPod, USB Devices

Holy crap.....the HyperJuice has a 11,000mAh small dual position stand that is sweet but expensive.

Yep, expensive. but thank you all the same.

Do you have a bestbuy close by? If so they may have this myCharge - Portable Power Bank 6000 Battery for Most Apple® Devices - RFAM-0007 I have found bigger ones, but you have to order them online, so depends on when you would need it.

Hs anyone had experience with iTrent external batteries.

I erred the previous post. It's New Trent, not iTrent.

I have not heard anything bad about them, the prices are resonable also.

Sent from my iPad using iPF

I have the New Trent 5000 mah battery. It does work well, looks nice, not toooo expensive. It performs, on the iPad, in the same manner that the iPad does when it is plugged into a USB port on the computer. That is, that the iPad claims "Not Charging" - but does charge at a very slow rate. I'm sure there are other external battery units that would be more compatible with the iPad, but I'm also confident that it would be a reasonable backup.

[[ EDIT ]] After having written the above, I plugged the iPad into the battery I listed. I have to report that after a while, the battery just turned off, and it doesn't look like it did any charging on the iPad. Now, let me state that I bought the battery for the iPhone, and on that device it works great. So, best to buy a battery that is specific about its being compatible with the iPad.

Don't forget that if you travel abroad (from where ever your home is) that you might run into wall plug incompatibilities with whatever you have, and might have to have the appropriate adaptors on hand.

Brian - Sent from my iPad using iPF

hi,Hope this can help you.
This Mobile Power Source can charge your device anywhere.
provides 30days standby time for your phone. Features excellent durability, the charging cycle-index can be over 500 times. Suitable for iPod, iPhone, iPad, mobile phones, MP3 players, MP4 players, PDAs, digital cameras, handheld game consoles, Bluetooth devices and so on. Add 50 hours iPhone movie playing time, or 17 hours iPad 2 movie playing time, or 50 hours iPhone internet time or 100 hours iPhone audio time.TPOS Multifunction 11000mAh External Battery Pack Power Bank for iPhone4 4S/iPad/Cellphone/Camera - DinoDirect.com