Battery behaving badly

[dodder92]

Since upgrading to iOS 9 the battery in my iPhone 6 has starting playing up. Between 100% and 20% it drains completely normally, but below 20% it will drain down to 1% in approximately 10 minutes. Does anyone have an idea what might be causing this?

 

[Leonard1818]

No but I would suggest doing a calibration of sorts.... first, hard-reset your iPhone by using both home and sleep/wake buttons, holding both at the same time. Then, plug into charger and let it charge fully, UNINTERRUPTED (Don't use it while it's charging) to 100%. Take it off and use it until it nearly dies (1 or 2%), then charge it fully again, uninterrupted. I've had some weird battery meter issues in the past and doing a couple of full drain/charge cycles usually puts things back in order. Be sure to power off your device every so often (not hard reset, just turn off/on).