Physics Van 3-site Navigational Menu

Physics Van Navigational Menu

Q & A: lithium batteries for head lamp?

Learn more physics!

Most recent answer: 02/20/2015
Q:
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
A:

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)

Follow-up on this answer.