Re: N900 battery life questions, issues, scenarios
 

Hehe actually it is a reminder for you to unplug your charger from your AC outlet as you are no longer charging the N900. I found that message to be a nice touch for both the environment and to save a lil on the electricity bill :)

Re: N900 battery life questions, issues, scenarios
 

There are two problems with that:
1: The message never pops up until _after_ you've unplugged the charger, thus it's useless.
2: The charger doesn't actually suck any power from the outlet when it's finished charging. There's no drip-charging of the battery, and the switch-mode charger is so efficient that what it uses when not charging is neglible. A user here on this board used some sophisticated equipment to measure the standby current on the N8x0 chargers, and came up with a wattage so low that the energy spent on the pop-up message (turning on the display and all) is much more than what you "save" by disconnecting it. (Obviously on the older devices the message actually popped up when the charging was finished, not when you unplugged..)

Re: N900 battery life questions, issues, scenarios
 

Ah ok always thought unplugging chargers when not in use was a good thing after seeing energy saving tips such as these.....

http://www.terrapass.com/blog/posts/...tricity-vampir

"Unplug chargers (think cell phones and iPods) when not in use. Only 5% of the power drawn by a cell phone charger is used to charge the phone. The other 95% is wasted when it is left plugged into the wall."

Re: N900 battery life questions, issues, scenarios
 

Me too. A nice touch that was a pleasant surprise, even if potentially confusing for people.

I'll plug the charger into my Kill-a-Watt when i get home and see what kind of power it draws when not under load.

Re: N900 battery life questions, issues, scenarios
 

Old chargers (non-switchmode), the heavy ones, did suck a little power even when just plugged with nothing charging. But those 5%/95% numbers are just picked out of the air. It would be about how long it takes for the battery in the device to discharge enough to engage the charging circuit again.

In any case, just forget about that - it's totally irrelevant for modern switch-mode chargers. It'll use something if you leave them in for years, but that's about it. As said earlier, any warning message popping up on the device will use (much) more power than saved by disconnecting the charger.

(There are still non-switchmode chargers out there though, for other types of devices. E.g. my laptop charger. It's of the big-transformer type and it's lukewarm even when not in use. Not that it would mean anything to unplug it, because the room is heated by thermostat-controlled electricity in any case.)

Re: N900 battery life questions, issues, scenarios
 

Hi,

Just to check the full charge behaviour of the battery.

After a full charge mine reaches only 94-95% (whether charged off or on). I have it for about 3 weeks now (initially once I saw a 97% charge). Typically I leave it to discharge completely before charging it.

Is anyone getting more than 95% after a full charge?

To check the percentage type in a terminal:

lshal | grep percen

Yesterday I left it overnight switched off charging. In the morning I switched it on (plugged it in charger) and the charging light went from green to orange for a few minutes and the battery level from 94% to 95% when it became green again and stopped charging. Is this behaviour what you are getting too?

Cheers

Re: N900 battery life questions, issues, scenarios
 

I just experimented and charged the battery to full using my E71. Put the battery back into the n900 and ran lshal.

Showed 96%

So perhaps lshal is not that accurate, under reports by 3-4% to help avoid dead battery? Some users have reported strange issues when the N900 drains

Re: N900 battery life questions, issues, scenarios
 

Never got lshal to show more than 97% after a full charge...

Re: N900 battery life questions, issues, scenarios
 

Reports anywhere from 94 to 98% here.

BTW it's better for your battery to not fully discharge. Smaller discharge cycles/more frequent charging is best use scenario.

Re: N900 battery life questions, issues, scenarios
 

The SmartReflex power saving feature of the OMAP processor is disabled by
default on the n900. To enable it:
You can also enable it by editing /etc/pmconfig and changing the appropriate
values to 1, and rebooting.

I've been logged in to my wifi accounts for 10+ hours now, with GPS on, and the
battery is only down by about 1/3.

Some power saving can also be achieved by setting your status to be offline and
disabling networking.

For further information follow the bug https://bugs.maemo.org/show_bug.cgi?id=6615 which has a somewhat higher signal/noise than this thread...