I've had my iPhone 4S for 3 years and it now runs iOS 7.1

Battery was performing badly so I decided to replace it.

  • I bought a spare battery online by duracell direct (average quality good!)
  • Replaced battery by myself (easy!)
  • First 2 running cycles are OK

Now, the iPhone shuts off at 30 % (sometimes at 20%). I can even reboot it and use sometines below 10 %, but experience is awful. Tried to do 2-3 calibrations but no luck.

I checked real battery status with iBackupbot, seems ok.

Here follows a log frm iBackupBot:

Info da iBackupBot il 30/12/2014

 CycleCount: 5
 DesignCapacity: 1430
 FullChargeCapacity: 1393
 Status: Success
 BatteryCurrentCapacity: 67
 BatteryIsCharging: true
 ExternalChargeCapable: true
 ExternalConnected: true
 FullyCharged: false
 GasGaugeCapability: true

Any ideas?

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    Jan 2, 2015 at 17:22

4 Answers 4


Few ideas:

  1. Have you tried a full blown factory restore?

  2. Are you SURE everything internally on your phone is secured and exactly as it was when you first opened it? Might be worth it to open it up again and double check.

  3. Have you contacted the battery seller? I've personally never heard of 'em, but then again I've never been in the market for a new iPhone battery. I would contact them and let them know about the issue. It very well could be that you were sent a dud.

  4. Last resort: Get it replaced. Not sure what would've gone wrong with the battery replacement, but there ya go. Contact your cell phone service provider or an Apple Store and see if you can either get it fixed by them or get a replacement.


You are either shorted something while replacing the battery or battery is a dud. That happens sometime. And since Duracell direct has nothing to do with Duracell brand of batteries it probably a dud.

Since it is not possible to get original one except from Apple service buy either few of cheapest or one of brand name compatible batteries that don't pose itself like genuine but usually have better quality then knockoffs.


When a phone shuts down at voltage levels that show 30 to 80% charge, it's almost always a faulty portion of the battery that causes the voltage to drop precipitously. The other reason would be a loose connection, so if you want to re-check your work, that would be good to focus on. I would expect the device to be much more flakey or you can rule out a bad connection by testing the device with it clamped to a workbench.

The charge remaining calculations assume the voltage decay is smooth since that's how Apple's batteries are designed.

This chart shows the charge stage and if your phone operated with a constant current drain, it would mirror this in reverse. Your device shutting off means that there is a chemical problem with the battery.

enter image description here

I would seek warranty replacement of the battery or buy another - perhaps with a better return policy if the one you bought has no warranty and/or no return policy.


It could be the phone hardware is not recognizing the battery capacity correctly.

Back up your phone to a computer. Do not only a factory reset but after that plug your phone back in to iTunes and act like you're going to reboot your phone while hooked up to iTunes. Once you see the Apple appear let go of the lock button but continue to hold the home button. This puts the phone in a "factory settings" mode.

It resets your hardware which a part of that recognizes battery capacity. It worked for me. Swapping those integrated battery throws off those apples.

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