What is the problem with my battery?

[iMore Question]

The battery usage will show a surprisingly low percentage but as soon as I plug it in, it will jump to a super high one. Ex. It was showing 5% and jumped to 75% as soon as it connected to a plug in. Do I need a new battery?

 

[Rob Phillips]

Welcome to iMore! You might just need to calibrate your battery. Here's how:
1. Charge your phone to 100%.
2. Unplug it and Let your phone drain its battery down until it shuts itself off.
2. Plug it back in and charge all the way back up to 100% without interruption.
3. Reset your device by holding the power button and home button down simultaneously until you see the Apple boot logo.
This isn't 100% guaranteed to work but it's worth a try. If you're still having a problem let us know!

 

[robertk328]

The advice @DevilishBanker provided is your best bet.
What phone is it? If it's old it may just be a battery that is at end of life.

 

[Ledsteplin]

Sounds like it's seen better days and is at the beginning of the end. My iPhone 5 started doing that.

 

[Rob Phillips]

Sounds like it's seen better days and is at the beginning of the end. My iPhone 5 started doing that.

My iPhone 5 had the same problem too after about a year and a half. Calibrating helped but I think the battery had just met its maker.