With the 510 XL batteries, I can get pretty close to 4 hours of fairly constant vaping. I have also found that most times when I think a battery has died that I can play with the knob that makes contact with the atomizer is kind of pushed down a bit and that I can bring it back up with a paper clip. I was ready to toss a few batteries, but after a little work, I was able to bring them back to life. I think it happens when I screw them down too tightly in the charger, and it depresses that knob (annode?)
Can you explain how exactly you did this? I have a battery that might have this problem.
By the way my 510 battery i got from LF lasted Sat, Sun, Mon, and Tues for me. Now using the second battery.