Samsung Galaxy S3 — Charging Issues

This sounds like a nightmare Mike, and I'm afraid I don't have a solution myself. I am suffering with my only battery troubles at the moment on an even older phone!

But you can have a look at this forum post: https://www.nextpit.com/forum/608623/how-to-calibrate-your-battery

or this article: https://www.nextpit.com/how-to-calibrate-the-battery-on-your-android-device

They might be good places to start

Hmm... it looks way to weird to me ! Like @Scott said you can try calibrating battery of your device... and if that still doesn't works. Try walking down the nearest support seeking help that battery is not charging over your device?? Why I am saying, as you have mentioned over your post that you have tried changing the charger as well as you have purchased two new batteries and this gives me a feel that problem is somewhere with the hardware i.e. the charging IC insider your device may be damaged. Try walking down the nearest customer support for fixing it ! I am pretty much sure the problem is defiantly with the charging IC.

Mike Buckalew

My SG3 takes up to 12 hours or more to charge. It says 100%, a few minutes after the phone is unplugged it's down to 20% or less. I have purchased 2 new batteries, same problem. I have tried my wife's charger, same phone, same problem. The only way it will charge is using my car charger.

IT SEEMS TO BE NOTHING BUT IC PROBLEM .WHICH LEADS TO CHARGING PROBLEM .BETTER YOU SHOULD GO NEAR BY TECHNICAL SUPPORT OFFICE THEY WILL HELP YOU IN SOLVING YOUR BATTERY PROBLEM.