I've had my Provari 2 for about a six months now. When I bought it, I also purchased 2 AW 18650 batteries to go with it. I've been running an Aspire Nautilus tank on top. In the last few weeks, I've noticed that I'm just not getting the hit that I used to from my setup. My wife is running a Nautilus on a MVP 20W and at the same settings, hers hits much harder. Could this be my batteries just no longer holding a full charge?