Tbh I haven't done any full on testing, have a.look online.I'm sure someone will of broke it down more, as I said disabling wifi will probably help as the 3ds farts about with streetpass stuff in sleep modeI tought that i was like SmartPhones. For example, my Htc One m8 loses 1% of battery every hour in sleep time. It's very good. I expected the same thing in the 3DS... I was wrong