My iPhone 4S keeps shutting down before battery is low

Question

Why does my iPhone 4S keep shutting down when it shows I still have 30% battery or more still available?   For example...my last phone started shutting down at 30% and by the time I took it to the store a couple weeks later, it was shutting down at 88% (they saw it for themselves, ran diagnostics, and came up with no issues).  Getting a new phone every 3 weeks is not ideal.  I'm on my 2nd replacement phone in 2 months and it started back up yet again-shut down at 31% a couple days ago.  I charge the phone to 100% and it never fails, it shuts down at a higher percentage each day (it shut down at 35% today).  I have done everything Apple Support has suggested with no luck (including full restore).  Is anyone else having this problem?  Any suggestions?

Answer 1

Hi,
I simply use the phone until I have only a little charge left. Once that's reached I'll simply let phone idle completely or drain the rest with lightweight use. We have big difference here as I can actually reach 1% rather than phone dying at 20++ percentages. Previous said, e.g yesterday phone just died after some use with 12% battery left and started again when bringing indoors. I was then able to drain the battery from 12% -> 1% before it eventually died completely. After this I couldn't start the phone anymore instead getting the charge icon constantly, so I just plugged it in at that point. After charging over night I would then consider the battery charge meter calibrated.
In your case you could test if you can still start the phone at 47%. Even if it's displaying only charge icon you could try to hold the sleep/power button longer and/or do reset with holding home+sleep/power button a few seconds. If it indeed doesn't start it would indicate battery truly is empty. It it does.. then you could try to continue using the phone hopefully hitting lower battery levels and eventually try to fully recharge it in case you'll see the battery charge percentage working any different.
Below picture shows I can still reach the  "0%" battery level and also pretty good usage times.. so the problem with me really is just that the stupid phone doesn't like cool temperatures (possibly after iOS6 upgrade)
-p