Wi-Fi is on when I turn on the phone

[AC Question]

When the phone is on, the wi-fi remains disconnected. But when I turn it off for the night, then turn it back on in the morning, I see that the Wi-Fi has turned back on AND my battery has lost power. As long as I keep the phone on, my wi-fi remains off and my battery power is actually conserved. I have a Samsung GT-6310T.