Just wanted to say that I have been using some of the Tenergy brand 3.0 volt batteries and have been quite pleased so far. This type of battery can be purchased at several vendors online as well as through AW. As for whether they are higher voltage than primary,I havent checked. but I have tried them in a Pelican M1,Pelican M3,Inova X5,Streamlight twin-task 1L and 2L. No instaflash on the twintask...does seem to be slighly brighter but not much.I have tried to blow the twintasks by rapid on and off and I can safely say at this point it aint gonna happen. On the LED lights no difference noted at all. I am sure they probably dont make the stated claim of 750 mah but even at 500 they are still a good solution for no hassle lithium use.