Batteries for lasers

What would be probably the best batteries to use in the PPL laser, PGL laser, and pen-like lasers? rechargeable or not? Does the rechargeable's 1.2V matter too much to not use them?

ps: I plan on getting a ppl laser within the next month to month and a half and was curious on what batteries to get for it because I know this thing will suck up power very quickly.

It all depends on how long you plan on running that laser for.

What exactly are you using it for?

it will be put on for good periods of time because I plan on doing many experiments with light and lasers in my school. We can't forget some fun with burning lots of things in a row... like balloons and matches and other stuff. /ubbthreads/images/graemlins/wink.gif

I think I read somewhere else that batteries that were a little more than 1.2v were good...someone also once said that energizer E2 batteries were good.

My PPL has had just one set of Duracell's in it ever since I bought it...the laser still works great, although I'm sure the output has diminished some since I first put them in...I'm the type of person that won't replace the batteries until it stops working. I don't have power meters and stuff to tell when the output is really degraded, so I don't pay attention to it...lol.