Why Time and Date displays in Sleep Mode

Just bought the LG V20. I noticed that when the phone is in sleep mode, the Time and Date appear at the top. It's dim, but you can still see it. Can this be disabled or is this built into the phone where it can not be disabled. I see the battery life in this phone is not the greatest so I am trying to find ways to save on the discharge of the battery by disabling the Time and Date at the top of the screen in Sleep Mode, any help or suggestions would be greatly appreciated. Thank you

rjgacek