Can someone put this blunty for me, and please give me links:

I would like a battery pack (which I'll only ever use for my N800) that can push the limits of usage 12 hours and beyond, without risk of damaging the internal pack. If possible, then 20 hours (or more, if existant, without possibility of damaging my N800!)

I want the longest usage out of my N800. Rediculous ammounts of hours. Im a writer, and a musician and this little gadget is a miracle I tell you!

Can you give me links to what I'd need to achieve this, please?

So far it seems the tekkeon 1550 is the best choice. but it doesnt look to me that it uses AA's; its lithium.

Any help would be great