Dazed and Confused....

Please forgive the question as I have searched and still havent found the answer I am looking for. <br><br>I want to jump in to the world of rechargeable batteries for my lights. I use Eneloops and Powerex AA and AAA in all of my smaller lights and I am now ready to move up to the 123's. After reading the posts and stickys, I am more confused than ever. It sounds to me as you can run these in some but not all lights. I have a various assortment of Surefire (all with Malkoff dropins), Malkoff, Elzetta, HDS, Solarforce, Sunwayman, Fenix, and others I have left out. I of course, still want to have primary batteries on hand for emergencies. <br><br>I am looking for a good charger and batteries that will safely power these lights without popping LED's like balloons. Maybe I am just dense and missing the point.<br>Anyone care to help me out with this?<br>Thanks

cr123 are 3v, rcr123\16340\18340 all 3,7-4,2V
watch voltage the light is made for.
ex. g3 uses 3 cr123 or 9v, you can't put 3x rcr123 cuz it will be 11,1-12,6v, you will burn the bulb, with leds it is a bit easyer, led drivers have greater voltage range, but you still have to make sure it is not lower than total voltage of cells you about to use. and you wont damage leds, you'll burn drivers.

I think the real kicker with rechargable li-ion batteries for those that are not familiar with them is that their nominal voltage is 3.7v vs 3.0 for regular cr123, but you also have to realize that a fully recharged li-ion battery is at 4.2v. Because of the higher voltage, they will not work and will probably destroy the light if it's not designed to run at the elevated voltage. This is a bit of information that you'll have to research for the light that you are want to use.

The next, but probably more important thing, is safety. Rechargable li-ions pack a lot of energy and if not careful, they can indeed explode. Obviously, shorts are never good, but especially with li-ions. So with this, you have two different configurations with li-ions. Protected and unprotected. Protected cells have a very small circuit board built inside of the battery casing where if any kind of overload is detected, it will shutoff the cell. Unprotected do not have this capability and thus require even more care when being used. Although they are cheaper, it is probably better to just use protected cells and not even bother with unprotected.

The only other thing that's probably worth mentioning is to keep batteries matched. That is, if you're going to use li-ions in a flashlight that requires more than one cell, then you'll need to keep them matched. So age, capacity, size, charge levels, even manufacturer and model all need to be the same. And to do this, you'll need to have some sort of voltage meter or multimeter to do this. If you're getting this far, then there's probably other threads on CPF that can provide you with better and more detailed information.

I understand about the ranges for the most part. Most of my SF's and Malkoff lights are running Malkoff M61 drop ins which can handle 3.4 to 9 volt. So I should be ok with them. My G3 has a M91 that can handle 6.5 to 12 volt. so thats kind of a grey area. Not sure about my HDS. All I know is it is a 140 lumen with a Golden Dragon LED. They sell recahargables on the HDS site, so I figure I am ok on that. Looks as if I am going to have to check each light on a individual basis.

Suggestions for chargers and batteries? I have read the AW protected cells are good but dont know what a good charger is. And yes, I have a multimeter and basic knowledge on how it works.

Thanks for the help to all.

The CPF forum Flashlight electronics, batteries included is full of information about Li-Ion batteries, and other types of rechargeable batteries. Do not just depend on this thread for all of your answers about rechargeable batteries. You have to be a very informed person about the risks/benefits of using such cells before you start using them. Tons of info on chargers in that forum also.

Bill