Safe chemistry batteries, those marked IMR, in a regulated, protected APV, are probably the best way to go no matter what. You have the protection from the device plus the safe chemistry means that the worst thing that may happen is they may leak, but they won't explode or anything. Lots of threads on this, and lots of Vets here with a passion about batteries. Surely, others will chime in about this along the same lines. I use only IMR Batteries, preferring AW, MNKE, Pannies, and Efest. Most consider the AW the safest IMR battery out there. Do some research on this forum. Don't worry, be happy!