Originally Posted by
Litespeedlouie
The OP missed several crucial details. The Fenix P2D is not rated to run on LiIon rechargeables.
Exactly.
And if the OP doesn't know that then he probably doesn't know that generic LiIon cells shouldn't be left to charge unattended - they have been known to burst into flames, although it's rare.
Anyway, the moral of this tale is
RTFM.