- Sep 23, 2018
I have this pretty cheap 1W laser for about 2 months now.
The ultrafires will get you by till you get better cells just don't keep them on the cheap charger long over never overnight I assume it came with.
True they aren't anywhere near 1300mah and the best 16340's will get you about 600mah.
Besides the 18650 being to wide it's also to long. just about double the length and you will need 2 3.7V to 4.2V batterys for that 1W.
Efest's are cheapest of the best and AW are great. I would go with "button top" unprotected as the protected cells can have fitting issues being that they are a tiny bit longer.
Being that you are in Slovakia what are your battery company sources?
Honestly there's not a really good way other than pulling the batteries out and testing them with a voltmeter. You can get an inexpensive multimeter (if you don't already have one) for probably <20 euros for basic stuff. A fantastic tool for all sorts of thigns though - so it's often worth getting a slightly better one.And how do I find out when the batteries get below 3V? Will the laser beam be less bright?