Check the ~DS drain issue (enable the screensaver for BETTER battery life, not worse) posted about here:
https://www.mobileread.com/forums/sh...d.php?t=294177
I don't get the lousy battery life most of you get out of my Oasis, although I find the battery life still too short for me.
I think there's some truth to the fact that every time you sync the device, it's best to just plug it in the AC. That way the indexing goes faster.
When I preloaded my first 600 books on my device, the battery dropped 10% per hour, so I left it plugged in for about 30 minutes.
The indexing mostly only get done, when new books are added, or maybe when booting the device.
After that, unplugging is ok.
I would also agree, that carrying 600+ books, isn't really the best; and would agree with CVKemp, to just load no more than 100 books on it.
You can always sync the other books to the device.
It takes quite some time to process 10 books, even for a fast reader, let alone 1000 books!
I turn off the wifi (airplane mode) as soon as the syncing was done, and I never read with screen light on.
It gets me about 2% per hour of battery consumption on Kindle books, but double to quadruple when reading PDF documents.
The Oasis' screen has sufficient resolution to display A4/Lettertype PDF documents, but the size is still too small (the characters are too small on screen), to comfortably read a PDF file.
It's like setting your font size to 0.25 (well below the lowest setting for kindle books).