Soon I'll get this http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=270748980459&ssPageName=STRK:MEWNX:IT light
It can use 2XAA or 1XCR123A batteries.
Well, I have at least three solutions
2Xaa alkalines (I wont use that)
2Xaa 2200mAh NiMh batteries
2 X14500 Liions (800mAh)
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And now totally unknown teritory for me:
1X CR123A LIthium (Li-ion??), CR123A is also 16340??
Should I bother with these CR123A at all? Can Liion charger charge Lhitium batteries?
On what batteries light would be brightest, and on which it will last longer?
Im "little" lost in all these numbers and possibilities. Can someone try to explain at least some of these issues? :) Not the mention thatI want to understand their votages in relation to battery and alll that in relationwith their capacity, but Im "somewhat" far from that understanding :) (total ignorant for electricity :o )
It means the driver can handle up to 4.2V so everything you have written above is correct. Well, actually (2) AA alkaline is 3.V and nimh is generally close to that right out of the charger.
You can't really say which will be brighter because it depends on the driver. If the light is designed to accept for instance both (1)18650 or (2) CR123 then neither will be brighter than the other.
Regarding what will last longer or run longer that's just a matter of knowing the capacity of the battery and converting the numbers to watt hours.
1 AA alkaline is 1.5V and 2Ah so 3 Wh Two AA's would be 6Wh.
1 CR123 is 3V and capacity is 900mA (I think) so 2.7Wh
Runtime is longer with the 2 AA's. I don't know if it would be brighter on one or the other. Probably not.