[quote author=Benm link=1194775080/30#36 date=1196074033]Protected or unprotected batteries make no difference to the laser, as both provide around 3.6 volts. This is more than primary lithiums that provide 3.0 volts, and could be a problem if the driver regulation isn't good.
The main problem with unprotected cells is that you can easily over-discharge them, which can render batteries unusable. Explosive malfunction due to deep discharge isn't common, that normally only happens when over-charging the cells (i.e. unprotected cells in a bad charger).