I believe the problem can be in the switch. The switches are not designed to handle the higher drain. I'm not 100% on this. I used LR atties on my eGo and the buzz was that the mosfet switch could fail when using the LR's. My eGo batt never had a problem for the 6 weeks or so I used it (I have since upgraded to a Provari). Unfortunately the nature of most of our e-cig stuff has poor quality control. For instance, you can get lucky with an atty that lasts months, and then the next one in the box dies the first day. (happend to me yesterday! arg!)