4s Battery Stops Charging at 100%

It's not supposed to do that. The device will stop charging when it reaches 100% but it should not go down if still plugged in. Your battery meter may be off... try this... fully discharge (till it shuts off) and then fully recharge (100%) the battery to recalibrate the battery meter.

I have the same issue, I did a full cycle last night and this morning when I took it off the charger it was at 91% after a few minutes. I will try to do another full cycle and I hope that will help.

I'm also noticed that the iPhone 4S battery meter is very inaccurate, the battery meter falls faster when it's more full and when it's below 40% it takes longer to drop a percent.

That's what initial battery calibration is for as paulcb pointed out...especially for a brand new phone. And after several normal charging cycles the battery meter should behave more consistently.

Full calibration isn't really needed often after that. Some say every month but that's way overkill, and actually bad for the battery in the long run. I just do it after a new software upgrade.

I had the same problem, while charging the phone the meter would drop below 100% and thats after its reached 100 %. In addition I noticed the phone wouldnt hold its charge. 😟 I was loosing about 10 % every hour and that

was with light usge, even if I wasnt using I was loosing significant power. I went to the Apple store and it got replaced. The one they gave me has that yellow tinge on the screen, not hapy. 😟

Are you guys recharging the 4S from a usb port or the small power adapter?

I've charged my 4S from just usb and once it gets to 100% (power plug displayed) it actually stays there... even if i use the phone.

I have the same problem too. I was using iphone 4, but iPhone 4 doesn't have this problem. Is it a new thing in IOS 5.0.1?

paulcb wrote:

It's not supposed to do that. The device will stop charging when it reaches 100% but it should not go down if still plugged in. Your battery meter may be off... try this... fully discharge (till it shuts off) and then fully recharge (100%) the battery to recalibrate the battery meter.

My observation is that the iPad charger output is reduced at 95 and stopped at 100%, the battery is allowed to discharge from 100 to approx 95% and then power is applied, this is identical to the behavior of a modern Mac portable with a magsafe charger. It's just like any other feedback system, actions taken by the supply (charger) are predicated on the behavior of the load (battery)

I would not be surprised to see the same behaviour on the iPod and iPhone.

the battery is allowed to discharge from 100 to approx 95% and then power is applied

I've never seen that with my 3G, 4S or iPad2. Once it hits 100%, it never goes down until I unplug it and use it.

paulcb wrote:

the battery is allowed to discharge from 100 to approx 95% and then power is applied

I've never seen that with my 3G, 4S or iPad2. Once it hits 100%, it never goes down until I unplug it and use it.

My iPad and my Macs exhibit this behavior, and it is consistent with LiPoly manufacturers charging recommendations, but is unimportant in use, as I said I have no iPhone so can not verify the same behaviour there.

Get a current clamp and wrap the sensor around the dc part of the magsafe, monitor it for yourself, the meters on the Mac are (at best) plus or minus 15%, never checked the iPad that way.

paulcb wrote:

the battery is allowed to discharge from 100 to approx 95% and then power is applied

I've never seen that with my 3G, 4S or iPad2. Once it hits 100%, it never goes down until I unplug it and use it.

You're not trying to tell me that once your iThing is fully charged it stays that way until used, no charge decline whatsoever when idle? or off?

Agreed upon the actual current/voltage drop, just never see it on the device.

Moot point either way.

If left plugged in, I've never seen it drop below 100%.

After unplugging, if not in use, it drops almost imperceptibly, i.e. I use zero or almost 0% overnight with the device sleeping.

If in use, it drops pretty good, although not as bad as some reports I've seen.

paulcb wrote:

If left plugged in, I've never seen it drop below 100%.

After unplugging, if not in use, it drops almost imperceptibly, i.e. I use zero or almost 0% overnight with the device sleeping.

If in use, it drops pretty good, although not as bad as some reports I've seen.

Well that part is normal, when unplugged it will slowly discharge until empty, or plugged in again, it may just be metering insensitivity but my iPad clearly shows a 'cycle' once it reaches 100%, and my Macs show a more distinct cycle which is in sync with the Magsafe led color changes, but like I said, ths is just a storm in teacup.