Why is the charge on my iphone 5s fluctuating from 85% to 2% and back to 85%?

[iMore Question]

For the last few months, my phone has indicated wildly varying charge on the battery. I will leave the house with 100%. An hour later, when I pull it out to use it, the charge will be 95%. Within 15 minutes, it will drop to 55% or so. Another five minutes will bring the low battery warning and the charge will be only 1 or 2%. Yet, when I plug it in to recharge when I get home, the charge level immediately reads 85%. What's going on?

MLEH

 

[Just_Me_D]

I don't know. It's possible that the battery or something in iOS has become faulty. You can try any of the following.

1. Reset All Settings
2. Restore your device and set it up as new.
3. Make a Genius Bar appointment with the nearest Apple Store.

 

[Larry Cook1]

When that happened on my daughter's phone they had to replace the battery. Apple store did it for around $84.00.