I can't give much info on battery lights as I am all dynamo. However, the Philips Saferide range does have a battery version which is meant to be very good.
Here is a good review for it -
http://reviews.mtbr.com/philips-safe...ights-shootout
And some beam shots...
Originally Posted by
Bluish Green
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Should you decide to go AA NiMH, there are no better chargers on the planet than those made by Maha. I own a
Maha MH-C800S. Electrically, it functions as eight separate chargers. Thus, you can spot and replace weak individual cells, rather than having to guess, or replace all four, and one bad cell won't spoil the charging cycle for all of them. It has three modes: Fast, "soft", and conditioning.
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Agree with both of these comments - if you go down the battery route.
I have less experience with li-ion/li-poly batteries and lights. The only thing I will say with these is that charging of the cells needs a little more care than NiMH and
definitely requires a smart charger if you are to avoid "venting".
Dynamo set-ups can be more costly, but have the benefit of not (unless of serious malfunction) dying mid-ride.