Battery Life Expectancy
 

After about 6 months with my N800,I'm finding that the battery life is no longer what it use to be. I use to be able to go 4-5 days between charges (intermittent use) and now the unit dies after 12-18hr while idle in "off-line" mode (no bluetooth or WiFi).

I realize that batteries dont' last forevery, but 7 months seems very short, expecially for a Li-Ion/Polymer battery. Occasionally, I've let the battery go dead, which isn't great for a Li-*, but I under the inpression there is circuitry to protect the battery in these cases.

Has anyone else had this experience? Am I doing something wrong (software or hardware)

Is this a warranty issue or should budget accordingly?

Lastly, is it worth getting a "non-Nokia" Li-Ion battery or are the Nokia Li-Polymer that much better.

Thanks,

Re: Battery Life Expectancy
 

There is a circuit in the battery to protect it from being totally destroyed, and there's also something in the N800 to switch it off before you get that deep down. Still, depleting the battery isn't good. Even a single deep discharge can damage it. I once let my phone run for three weeks without charging (switched off at night though) because the connector was broken. After that it needs recharging every second day.

My N800 battery seems to be doing well after 9 months. I normally charge it whenever I see it drop down one or two bars, although it's happened two or three times that it discharged during the night (until I disabled a certain crawler program..).

Re: Battery Life Expectancy
 

when my battery started to die overnight, I found it was caused by a faulty SD card. There was some process trying to read the card all the time and the CPU was high. Thus, the battery was dead every morning. I tested by removing the SD card and then my battery usage went back to normal.

Re: Battery Life Expectancy
 

I actually bought one of these:
http://www.dealextreme.com/details.dx/sku.4284
More than doubles the battery life and it comes with adaptors for other phones too...not that I use any.

Disclaimer: I am not affiliated with dealextreme.com...just wanted to share a nice gadget.

Re: Battery Life Expectancy
 

Before you shell out for a new battery I would check to make sure you don't have something running in the background on your tablet that's sucking up the battery. I've had mine since March and I'm still getting 8-12 hours of standby with occasional usage with wireless on. If you were getting that kind of battery life with wireless on I would suspect a connection being held open or the use of ad-hoc wireless (powersaving modes can't work well in ad-hoc mode), but if wireless is off I don't know...

Re: Battery Life Expectancy
 

I found after implementing this:

1. Start an xterm
2. insert following command in xterm
ln -s / /home/user/MyDocs/root
3. exit xterm

metalayer crawler used up all available CPU chewing up my batteries. If you've done this, either implement this or delete the link to root.

Re: Battery Life Expectancy
 

I noticed the same thing recently. My N800 is 6 months old and my battery lasts now approx half as long as it used to be.

There are no CPU consuming processes running, actually I haven't changed anything in the last weeks at all.

Re: Battery Life Expectancy
 

I took Alivin's advice and removed the SD cards and battery life is significantly better. Not sure what was happening, but I'll play around with the SD card to see if a slot or card issue. Thanks for all of the help. :)

Re: Battery Life Expectancy
 

I bought the exact same gadget when I was in HK last week. Works very well for my n800, Dopod 838 Pro, and bluetooth headset. Wouldn't charge my Ipod 5.5G 80Gb and my wife's 3G Nano 8Gb for some reason i can't fathom.

Re: Battery Life Expectancy
 

Thinking I need one of these for gadgets sake. will be a nice backup for my backpack

Re: Battery Life Expectancy
 

I flashed my n800 several times. I always install a lot of stuff, so I couldn't track what was killing my battery even when in offline mode and locked. By reading this thread I came to realize that the problem could be that I was using virtual memory (swap on my mmc card).
Once I stopped the swap, the battery keeps the n800 for days.

Re: Battery Life Expectancy
 

Thanks for the hint! I'm seeing quite disappointing battery life on my n800 that's just a few weeks old, and I guess this might have been it. I do have a swap partition (which is hardly ever used), and I'll try without it.

Anybody knows if booting from SD card might also affect battery life?

Re: Battery Life Expectancy
 

Since the first days of my N800 I had a swap file on the internal SD card (original card from Nokia). No problem with the battery for months. Just recently it started aging. Already ordered a cheap chinese replacement from ebay.

Re: Battery Life Expectancy
 

Could it be related to the new kernel and not the aging of the battery? did u try lately without swap?
In my case it was the only thing I did to regain the life of the battery.

Re: Battery Life Expectancy
 

I'm starting to believe this problem is coming from the new firmware.. probably the one that was supposed to fix some corruption problems in SD cards.. maybe at the cost of draining the battery. My N800 was fine till a some 3 weeks ago and the battery used to last for several days. Now it can't even last for 24 hours! Aging doesn't really make sense.. batteries don't age in a week!

Re: Battery Life Expectancy
 

if the battery dies in less than 24hours then find out what app is hogging all the CPU.

Re: Battery Life Expectancy
 

I don't have the new firmware yet, and I don't have any CPU hogging programs running. Since about 4 weeks ago my battery has only about half of its capacity. 2-3 hours browsing, compared to 4-5 hours before.

Soon I will get a cheap chinese replacement and will check and report its capacity here.

Re: Battery Life Expectancy
 

I tried now leaving the n800 without charging connected to wifi and running pidgin overnight and there was still battery for another 5 days.
So for me the fix was removing the swap option.
Also I am very happy to know that I can now be online 24x7