why is my phone charging so fast?

My phone usually charges too fast. When I put it to charge 10-15 min after he is fully charged, but if I restart it he goes under 30% and then take another 10-15 min to charge.
Can anyone help me?

from Android Forums at AndroidCentral.com - Ask a Question http://ift.tt/2bqkpLz
via IFTTT