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Q & A: lithium batteries for head lamp?

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Most recent answer: 02/20/2015
I have a variable led head lamp that is powered by three AAA batteries. I would like to use longer lasting 18650 3.7v ion batteries. Could I use two in series?
- Rex (age 50)
Honolulu, HI

LED's are pretty sensitive to high voltages, so I wouldn't replace a 4.5V set with a 7.4V set. You can get lithium AAA batteries that can be used as straight replacements, and will last significantly longer than alkaline batteries.

Mike W.

(published on 02/20/2015)

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