I'm a total newbie.  I just got my 510s from Innovapor.  I got 5 manual batteries and two of the single-piece USB chargers, among other things.  When I plug the charger into the USB port without a battery connected, I get a solid blue light on the charger.  When I connect a battery to the charger I still get a solid blue light on the charger.  It's the same thing with all 5 batteries and both chargers, so they must be working correctly, but does that mean the batteries are already charged or not?  If I vape with any of the batteries, the LED on the battery turns on solid, but then starts blinking after 2 or 3 seconds.  Does that blinking mean the battery is low or what?  I do get good vapor, but I'm afraid of ruining my batteries or atomizers by running my batteries too low.  Help!