Why is my Samsung Galaxy S4 charging som slow?

[AC Question]

Help, my S4 is charging really slow all out of sudden. About three weeks ago, it took aproximatly 2 hours to charge the battery from 0%. Now it takes 6 hours or more to fully charge IT without wi-fi activated or me using it once. I got a new battery about a month and a halv ago because the old one was almost twice as thick as it is suposed to be, so I don't think it's the battery that is the problem. I've tried different cables and chargers, but it's still taking ages to charge. It also uses a lot og battery when I'm not using it, which is a BIG problem considering how long it takes to charge it. In the settings I check what uses all the battery almost every day, it says that "Android-system" has used between 20-60% of the battery everytime I check it. Please help me!