Samsung Galaxy S5 mini not charging properly

[GleekyTobi]

Hello everyone,
I've been having some problems with my Samsung Galaxy S5 mini phone. Out of the blue it started not charging past 85% maximum and on further charges it wouldn't charge past 68-70%. Once it got to about 70%, the battery percentage would then decrease while the phone is still plugged into the charger then once I unplugged the charger, the battery percentage would increase again.
I went to a samsung support and repair center and they told me I had to buy a new battery because the current one was faulty. I replaced the battery with the new one I just bought but the problem hasn't been fixed. Now my phone will charge to 68% then the battery percentage will decrease to 30% then go up again to 68% and so on. I factory data reset my phone also but this made no difference.
I'm writing to ask if anyone has had this problem before and if they managed to fix, then how they were able to do this?
Thanks
Tobi

 

[baldpaul]

Have you tried to completely deplete the battery to the point the phone turns off? If not, I would do that and then charge overnight to whatever's its maximum is then let the battery drain down until the phone turns off again. Then do another overnight charge and see if that finally gets to 100%. The phone maintains stats on what it believes 0% and 100% charge is but the stats can get out of date and doing a complete discharge and full recharge a couple of times should reset the stats. If that doesn't work then I'm a bit stumped.

 

[GleekyTobi]

Ok thanks very much I'll try this then update if it works or not