I just witnessed an interesting battery phenomena so I thought I should share it with all of you guys here. You know how everyone says the battery life sucks, and how you need to do everything from disabling the LED's, 3G to even Internet (yah on an Internet phone) to get the maximum battery life. I followed a bit of that too, and what I discovered along the way was irrespective of what I did (Autodisconnect), disable Wifi the battery would discharge at pretty much the same rate even in Standby, draining about 20% in 8 hours without much activity (like no IM etc).

But then something changed over this whole week, the battery is draining only 1% per hour (sometimes even less) in Standby - connected all the time to the Internet via WiFi, checking mailing via Nokia Messaging which means, I could probably use it this way for about 80-90 hours (or 4 days!!!), which is good enough for me!

My best guess is all this has to do with somethings I have changed, though it will difficult to pin-point which one did the magic. So, here's what I have done, what worked and what didn't, it might just help you.


1. Installed Autodisconnect. Not much change in standby time, but 5-10% improvement.

2. Disabled GPS. Not much change in Standby time.

3. Change Wifi transmission power to 10mw. Not much change, or nothing noticeable. In fact it made it more difficult to connect from several places in the house.

Now on to some of the things which may have changed the battery.

4. Reflash to 1.2 (eMMC as well). Changed battery performance by about 10% straight away

5. Reset my Wifi router. Change from Mixed mode to Wifi G mode only.

6. Disable IMAP mail checking and setup Nokia Messaging. I thought this would reduce battery life, but this is what I am using now while getting 4 days of standby time.

7. Discharge battery fully couple of times, and recharge.

8. Change Wifi Power saving setting to Intermediate

Currently I am getting 4 days of standby with the following settings.

GPS & Network Location On, Wifi Powering Saving set to Intermediate, Autodisconnect disabled, N900 connected to Wifi all the time during Standby, Nokia Messaging Mail configured with one IMAP account, Phone mode set to GSM, Brightness set to 2.

I am sure it's one of the things I have done. But it's amazing. I even timed with light load, a few hours of calling, 1-2 hours of Wifi browsing and I am getting 2 1/2 days.

I'm also pretty satisfied with battery life, it is roughly the same as yours or even few days longer with light usage. I guess that standby time could be as long as 7-8 days.

Reflashing made the biggest change, as cpu won't get any load when idling.

edit. I was really losing my mind with this battery life issue when I got the phone, it was the biggest flaw in the device. How many user are there who still have to charge their phones all the time

Nice you made it to that point! But setting "Captain Obvious" power settings like wifi to 10mW and powersaving, using 2G instead of 3G, reduce brightness or to not pull mails every 10mins is no magic to me.

Running on 3G drains the battery within 10hours.

2 1/2 days is normal to me, I also made +3 days once as I needed it to be available using it as navi for 20 mins doing a few cell calls and keep it in cell-phone only state for those 3 days made me charge it back home again at about 20% which might be another day in this case as my phone remains about 12hours in standby at 0% shown. The percentage shown is a quick tell where you are about but is nothing like precise. Unplugged 10th drained till today 12th July 50%, with a longer phonecall and most of the time online.

For powersaving, all widgets updating from the internet will reduce your battery life so will anything else which is powerhungry. I guess my previous phone did about 1 1/2 weeks stby and I bet I will get that out of the n900 if I use it as cellphone only. You pay a price for always on' and lots of gadgets and blingbling.

If you get somwhere around 6 days let me know please.

Sorry to tell you off like that! I am happy you made it to those 4 days anyway

As told above, getting the 7-8 days as cellphone only shouldn't be that of a problem. But getting more than 4 days with light-medium usage (some calls, some chatter, always on but nothing really active is getting me up to 3 days) is my goal.

wow...i still have to charge each night to make sure i can still use it in the morning, although i put it in offline mode at night.....i could easily get a day and a half but that would mean that i have to be content with knowing that my n900 is at probably 40 to 45% next day at work.....i still haven't got the nerves to flash my n900 yet.....i really should try it to maybe see some solid changes.....

Brightness set to 2 is what helps you the most and 2G instead of 3G.
Set your brightness to 5 and you will see

thanks for the info.

Sorry for repeating myself, but you should check what is your processor up to.

When the phone is locked without any apps on there should be 0 % load. BatteryGraph is a fine help.

Instructions for flashing:

http://discussions.europe.nokia.com/...ata/m-p/591877

(I did only the first part, did not reset mass memory..)

I just hammer it daily and carry a spare battery. I want the most of the device, I want instant mail pickup and why suffer a dull screen and 2G speeds just to avoid plugging it in?

On second thought I am not sure if I can even call my current setting Standby (or maybe it is.. hehe), because it is connected to the Wifi continuously all 4 days I did the test, and was checking mails via Nokia's "Push" Messaging. This in sharp contrast with my earlier set up of Autodisconnect and Offline setting in the night.

You could try overclocking + lower cpu voltage profiles to cut that "active-time" battery usage. I personally use "starving" voltage profile and 250-900 MHz clock limits. There is no way to measure the effect, but there might be a minor improvement and the phone is faster at least

10mw?
lol
check ur download speed.. 25kbps :P