R18650 vs CR123 batts- what's the diff?

infinitium

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OK, so pardon the silly question - I'm new at LED flashlights and the flashlight collector community... as I was browsing this forum, I see lots of references to "R18650" and Li-On "CR123" batts.

Discussions seem to favor flashlights that feature/use R18650 batts... can someone help me understand what's the difference btw these two? Pros and cons?

When buying a new light, what batt should I look out for? Is it important/a deal breaker if the light only uses CR123 or only R18650?

Thanks dudes...
 
OK, so pardon the silly question - I'm new at LED flashlights and the flashlight collector community... as I was browsing this forum, I see lots of references to "R18650" and Li-On "CR123" batts.

Discussions seem to favor flashlights that feature/use R18650 batts... can someone help me understand what's the difference btw these two? Pros and cons?

When buying a new light, what batt should I look out for? Is it important/a deal breaker if the light only uses CR123 or only R18650?

Thanks dudes...

There aren't any R18650 batteries. There are 18650 batteries and there are RCR 123 batteries and CR 123 batteries.

All 18650's are rechargeable lithium-ion batteries (li-ion).
CR123 are primary (non-rechargeable) lithium batteries and RCR 123 are the rechargeable version of that battery size.

18650's typically are nominally 4.2 V and a standard capacity is 2500 mA. A light that uses (2) Cr123's may also use (1) 18650.

CR123's are 3 V and typically 1500 mA (I think).

If a light is not constant current regulated the bottom line is that with (2) Cr123's you will have 6 V and the light may run brighter. With (1) 18650 the capacity will be greater and the light may run longer.

CR123's can be expensive if purchased locally. I've seen them for as much as $9 each. Online you can get them for $2 or less.

As far as I know 18650's aren't sold in the stores but only online. They are chargeable and affordable.

Those are some of the issues.

I should add that some people only want alkaline AA's as they are cheap and commonly available. Other's only want Cr123's or 18650's. Alkalines are a high internal resistance battery. They last a long time but with today's higher current drawing leds they sag (can't continue producing max power for very long at a time). Lithium batteries are a low internal resistance battery and can operate at close to max output for longer periods of time.

Alkalines also don't do as well in really cold conditions (think 20 degrees or something like that). Lithium batteries have a very long shelf life as well.
 
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One small bit to add, 18650s are nominally 18 mm dia, 65 mm long, while CR123s and RCR123s (a.k.a. 16340s) are 16mm dia and 34 mm long, so size may also be a consideration in what you purchase.
 
1*CR123A/RCR123A torches are quite small. 2.3 inches long for the Quark Mini 123. Very pocketable.
If you do not have a light with you at all times (EDC) then you do not have a light at all because Murphy's laws says you will need a light when you are not carrying one.
1*123A lights fit in the pockets of jeans. 2*123A/18650 lights require cargo pants.

2*CR123A lights are dangerous if they are not balanced. See
http://www.flashlightreviews.com/features/123burst.htm

RCR123A are 3.6V and you have to be careful your torch is rated for 3.6V. Many torches work only with 3V CR123A. See
http://www.flashlightreviews.com/features/rechwarn.htm

Do not overchaarge (voltage >4.2V and current >2C) nor overdischarge (voltage <2.7V and current >2C) Li-ions. See
http://www.candlepowerforums.com/vb/showthread.php?t=235164

Take good care of your batteries and you will be happy.
 
1*CR123A/RCR123A torches are quite small. 2.3 inches long for the Quark Mini 123. Very pocketable.
If you do not have a light with you at all times (EDC) then you do not have a light at all because Murphy's laws says you will need a light when you are not carrying one.
1*123A lights fit in the pockets of jeans. 2*123A/18650 lights require cargo pants.

2*CR123A lights are dangerous if they are not balanced. See
http://www.flashlightreviews.com/features/123burst.htm

RCR123A are 3.6V and you have to be careful your torch is rated for 3.6V. Many torches work only with 3V CR123A. See
http://www.flashlightreviews.com/features/rechwarn.htm

Do not overchaarge (voltage >4.2V and current >2C) nor overdischarge (voltage <2.7V and current >2C) Li-ions. See
http://www.candlepowerforums.com/vb/showthread.php?t=235164

Take good care of your batteries and you will be happy.
Maybe I have fat-man pants or something, but a SF G2 fits into the pockets of my jeans fine, but I prefer belt holster.
 
When buying a new light, what batt should I look out for? Is it important/a deal breaker if the light only uses CR123 or only R18650?

Thanks dudes...

As a beginner, you should either buy a single cell light which runs on a CR123A and accepts an RCR123 or a two cell light which runs on 2 x CR123A and accepts one 18650.

As you have no idea about li-ion at this time, you may want to read about them here, check the battery section, there's a sticky with lots of usefull links. First get the knowledge, then decide if you want to go that way or if you'll stick to primaries.

If you buy now a light which runs on primaires (also called lithium cells), which accepts rechargeables (also called li-ion cells), you may switch to them at any time. Once you own a drawer full of different li-ions, lights that only accept primaries will perhaps become a deal breaker, but not those running on an 18650 only, you'll look for those! :naughty:

We'll take about the regulation of lights on different cell configurations later I propose... :poke:
 
Thanks so much guys! This is certainly very helpful.

I'm gonna be looking out for the AW R18650 rechargeable Li-Ons... thinking of getting a Fenix TK12 R5. Am hoping the TK12's take the R18650 2600mA ones! (do they?)
 
Welcome to CPF, infinitium :)

We have a separate sub-forum for battery-related questions, so I'll move your thread there.
 
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