Iphone 6 ios 11.2.6 battery problem

Hi i have some problems with the battery after upgrading to ios 11 , i can’t see any battery usage data and another problem is that the battery percentage is bugged , for example: when i charge my phone the battery charging slow after 60% then when i use it the battery percentage remains stuck at 100% for a while then starts to drain fast and then when it’s at low battery level it’s draining slow. I have that problem after upgrading to ios 11 from ios 10 since a month ago. The battery is new , i changed it before updating to ios 11.

Hope that problem will be resolved in ios 11.3.