N900 Can't Charge to 100%
 

Anyone know the reason why the N900 can't charge up to 100% the furthest I've got it to charge is 96%. I read in a thread Lithium batteries shouldn't be charged to 100% or something like that

Re: N900 Can't Charge to 100%
 

Its the BME on ur fone which charges your phone upto 97% but if u want to charge it to 100% then i think u will have to stop BME from the xterm while on charging.

Re: N900 Can't Charge to 100%
 

Is your battery old?

You may well find that it quite simply can't be charged to "100%" any more (and 100% is a fairly arbitrary voltage level, and the percentage to voltage curve may well be non-linear depending on what the Nokia engineers decided people would want to see.)

I've no clue where the idea to stop BME has come from; without that running you won't get any battery charging at all (and you'll probably also get an automatic reboot in an attempt to restart it.)

Re: N900 Can't Charge to 100%
 

Lithium batteries don't ever want to be totally charged or discharged. The effort involved in either is futile.

On the charging side, picture a wall of small boxes about 20 inches cubed. Now randomly throw a bunch of balls (just under 10" diameter) at the wall and try to fill all the cubes up perfectly. That's how a lithium battery charges... Getting it up to 75% is easy, beyond that takes a lot of extra throwing, which builds up heat and wastes energy.

On the other side, discharging it is like pumping water out of a well with a submersible pump. You can get all but that last couple percent out pretty easy. But below that, your pump has to work extra hard, the flow is irregular, and it quickly builds up heat and eventually the pump will fail.

Most devices never tell you a percent. They show you "4 bars" or some such. In that case the break down is usually about 17% per bar, with bars representing >75%, 74%-57%, 56%-39%, 40-23%, and 22-5% being NO bars. If the battery only charges to 92%, the first bar lasts just as long as the others. And as long as its over 75% the user thinks it's "at max".

Re: N900 Can't Charge to 100%
 

maybe be turning of the phone than charging it while its of will charge it to 100 % but it will loose like 4% (or something like htat, i don't know really ) while its booting up .

Re: N900 Can't Charge to 100%
 

It's not a problem with the charger, it's a problem with the battery meter used in maemo5.

Re: N900 Can't Charge to 100%
 

The number reported isn't all that accurate. Just because 100 has three numbers and 96 has two, don't worry about it, its supposed to give you a general idea of charge, not a highly precise measurement.

On the N900, the BME is not required for charging, but without BME it will charge very very very slowly.

EDIT: woody14619 has a very good explanation if you were interested in the actual charging behavior of lithium batteries.

Re: N900 Can't Charge to 100%
 

well guys my battery isn't old my phone is 2weeks old so not it aint the bat. i believe d ans with the balls n the wall

Re: N900 Can't Charge to 100%
 

I've charged to 98% one time, very briefly but normally 97%. If you charge via USB whether it be laptop or A/C your values will differ depending on how long you leave it charging. As you know after awhile it will begin to lose the charge, hence the message given when you unplug after a full charge, "disconnect to save power".

I have an extra battery that I will just leave in for days at a time in the charger and usually on the weekend or whenever I replace the battery, it's always @97%.

Re: N900 Can't Charge to 100%
 

scribbles I like ur signature with the blackberry blacked out thing lol epic

Re: N900 Can't Charge to 100%
 

Not to res a dead post, but i've had my N900 plugged in overnight like I always do and this morning the charge says 81.6%.

Seems kind low for an overnight charge.

Re: N900 Can't Charge to 100%
 

how old is your battery? sometimes, bad maintenance of a li-ion battery can reduce the maximum charge it can hold.

Re: N900 Can't Charge to 100%
 

The battery meter is broken. The charger isn't.

Re: N900 Can't Charge to 100%
 

actually battery meter could be working fine also.

after li ion has been charged full, charging stops and everything works just like device isn't plugged to charger until battery level hits certain point, probably 80% with n900. when the limit is reached, charging starts again.

constantly charging would wear the battery quickly. really quickly. nimh was the best for overnight charging.

Re: N900 Can't Charge to 100%
 

Well, it's the battery that came with the N900, so its about 7 months or so old. It's not something that was happening before. I'll check again tomorrow and see how it goes.

I need to get an extra battery anyways. I don't really want to get one from Nokia, as I'm sure they cost an arm and a leg. Any suggestions on a second battery?

Re: N900 Can't Charge to 100%
 

Exactly, and if techngro installs BatteryGraph he can see where charging reaches peak and then stops, and battery slowly gets lower overnight. (If this is indeed the case for him)

In my case I can see that after putting it in the charger at Midnight, the battery reaches full charge around 3:00 AM and then slowly drains after that, never reaching the level needed to trigger the charging again by the time I wake up around 8:00 AM.

Since I don't want to start the day with 15% of my charge missing already, I unplug and re-plug the charger to the wall, which triggers charging again. By the time I leave for work 40 minutes later, it's full.

Another workaround is to turn off your phone at night. :)

Re: N900 Can't Charge to 100%
 

Btw, I think when plugged to a pc-usb, the device won't charge beyond 60% charge... Not 100% sure though.

Re: N900 Can't Charge to 100%
 

No it will charge as full as with wallcharger as long as the device isn't using more power than the computer can provide. that kind of drain would be equivalent to a 3-4 hour battery life

Re: N900 Can't Charge to 100%
 

N900 won't charge your battery to 100% even you're trying until the N900 explodes.

The highest I ever got it to charged up is 98% a few times.
Once it's full it will not charge again until the percentage is dropped below 85%, to make the N900 recharge again you have to replug the MicroUSB.

If your battery won't charge beyond 60% then either you didn't calibrate (deep cycle) it properly since new. You have to give it a full charged for a few hours before using it other wise your battery mights end up like this.

Recommendation is to get a genuine Nokia battery, the cheap chinese made one won't last very long after charged up. And I would preferred original Nokia just to be on the safe side. N900 is now discontinued therefore you should take good care of it.

Re: N900 Can't Charge to 100%
 

my n900 showed full battery at 96% when i replaced its battery with a X1-01's battery which is a 1500 mAH battery but now whenever my phone shows fully battery while charger is connected its always at 86 percent i dont know why.