Uh, so the battery is charged and ready when you need it? If you're sitting at your desk, or leaving it on a counter-top somewhere, why wouldn't you plug it in?

I too just discovered this on my own N800. I thought I accidentally swapped the 770's battery into the N800 and it was just getting old, but when I switched batteries it has the same symptoms.

Today I tried an experiment: Full charge overnight, then leave it in my pocket (standby) all day (which included an 8 hour shift at work - not on wifi or bluetooth.) It's 5 PM now and I am getting battery chimes. I'll try a firmware format to see if there's a software culprit.

Because its a portable device with an advertised standby of 10 days or something:

"The rechargeable battery provides up to 10 days of standby time"

So the question is why can't the n800 meet its advertised specs? On 2007 I was lucky if it didn't die overnight which is real fun when you are using the alarm clock mode. On 2008 its much better but I must go to offline mode to really have decent battery life.

you can also try switching your wireless router to "802.11g Only" mode, which will use less power.

It meet it's advertised specs - in fact it exceeds them by a considerable margin - if the device is left completely idle and not used at all!

I just performed a rundown test on a freshly flashed and fully charged N800/OS2008 with no WiFi connection, no RSS applet enabled, no backup restored and no additional apps installed. Total time before first "low battery warning": 12 days and 2 hours. Of course I didn't use it at all during this period and only tapped the screen once a day (which switched off again 10 seconds later) to check it was still switched on!

I'm now performing a second rundown test with 11g WiFi enabled and I'm already down to 1 battery bar after 3 days and 11 hours - I'll be lucky to make 5 days with an idle but always connected WiFi connection (my router supports PSM).

Once that test is complete, I'll be enabling the RSS applet to update feeds every 30-60 minutes and see what effect that has on the battery lifetime - obviously the number of feeds configured on my device will be a major factor, so I'll just start with the standard/default feeds.

So far though (and without having tested the RSS applet) I'd have to say that the stock OS does not have any obvious power management issues. As is often the case, if your devices are not lasting 24 hours it's because of a badly behaved third-party application which is not allowing the CPU to go to sleep and is chewing it's way through your battery in no time. Unfortunately which application is causing the problem is not always easy to identify.

I also encountered this problem after upgrading to the 2008 OS. My N800 had been remarkably stable prior to that (uptime of a couple of months), and then the battery life dropped to hours instead of days. There were no obvious culprits (I was using the same access points, or no access point, and auto-connect was off).

I haven't had much free time, and was just gradually restoring my customisations when I could, and then the problem suddenly went away. I'm pretty sure what did the trick was adding a "-c" argument to the metalayer-crawler startup, but I haven't had the time to verify that this was really what did the trick.

More specifically, I think the problem went away went I edited /etc/init.d/metalayer-crawler0 to pass the following option to the daemon:
Anyone else having this problem might want to try something similar.

Cheers,
Lon

I'm getting this with my N800 and now having an N810, I'm getting it on that too. I've updated the bug report,

https://bugs.maemo.org/show_bug.cgi?id=2602

Rich