Is it brand new? I've noticed that it sometimes take few cycles for it to calibrate (NST for me and NT for my wife).
I have it about 2 weeks, charged it about 2 or 3 times.
My battery life is horrible. I too only use it for reading, wifi is always off & I have power save on & screen dimmed. It has only gotten progressively worse and now have to charge mine about every 24hrs. It drains significantly even when its asleep. The longer I have my NT, the more I wish I'd kept my NC.
To the OP and others suffering excessive battery drain. There are a few other threads on the topic and with wifi off and screen brightness low there are just a few things left that could cause this:
1) Background applications that are still running like QuickOffice Pro or a sideloading PDF file. A SD card installed is not part of the excessive drain thoughts as some have suggested. I have a 32gb card and it caused no difference.
2) Defective battery - nothing more really to say about this except for what I mention below.
For #1, it has been suggested (successfully) to either do a soft reset at first and then a hard reset. Either one should/will stop your background apps. No telling if they will start right back up again especially if they were configured to do something when restarted. Out of the box, all should be good and you should get anywhere from 8-11 hrs of quality time using your NT with wifi off and screen brightness low just doing some reading activity.
#2 is cause for replacement. I've seen a few posts where this happened and you really can't tell if your battery is defective if your battery drain is close to the low point of the average. These lithium batteries are not recommended to fully drain to zero so you might be able to gauge the battery capabilities if you turn your NT completely OFF for the night and check percentage the next day. Mine does not drain more than 1-2% and this is for about 8 hrs or so.
I am sure there could be some other influential functions causing the excessive drain however you have to start somewhere and while #1 is fairly easy to troubleshoot, #2 should be figured out right away while under the 30 day replacement policy. Just some suggestions.
With some† exceptions, applications do not run in the background on Nooks (that's why you don't have multiple windows viewable at the same time).
†— Exceptions (this list is not all-inclusive):
- WiFi runs in the background.
- If you have set up your eMail app to check messages, that runs in the background.
- If you have the browser open to a web page, some web pages are dynamic, meaning they run while displaying. They're not supposed to run when the web page is not being displayed, but ...
- A few system apps run in the background, like to check for updates & new downloads on the B&N site.
Generally, a document-displaying app does not run in the background (there is no reason to).
I would check items #1 – #3 as a first step, and then reboot your fully charged Nook and then don't run anything after rebooting. Let it sit overnight, and see how much it drops. If that only drops a little, then by the process of elimination, try to figure out what is draining the battery.
I turned it off and 7-8 hours later it had the same percent.
@mitch520: You have pretty much ruled out that the battery is defective and you can focus on things causing the drain. There are a lot of things to look at from the posts above. When I had my Palm T|X I had an app that listed all the running functions and their battery drain. It was created exactly for this sort of purpose.
Any Developer out there who can create one for the NT?