RCR123 vs 18650

Nimravus

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How substantial is the performance difference between these two battery types?

Lets use for exemple the TK11 or the Olight M20 both can be operated on eigther 2 x RCR123 or on one 18650. Will the 18650 out last, out shine or both the 2 xRCR123's.

Also how do these batteries keep their charge in shelf time? In the light but the light not being used?

Also how do they resist to cold and do they keep a decent charge in the cold? Note cold not cool weather (-20C or -4F and below)

I am from Canada a winter campers dream and as many of you know flashlights become very important in winter camping and in cars as days are short. What is my best alernative or should I stick to primary cells for winter aps?

I am considering trading up my TK10 for the TK11 R2 or the M20 Pre R2 and also mayber getting a TK40 or M30 so I need to know what batteries to be getting and how these batteries perform as this may be a serious investment.
 

Yucca Patrol

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As a rough estimate, one 18650 battery is equivalent to three RCR123's.

I don't bother to use the RCR123's but love 18650's.
 

yellow

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yup.
same sized ligh (2*CR123 <-> 1*18550)
less loose parts
roughly 1/3 more power with 18650
 

NoFair

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As a rough estimate, one 18650 battery is equivalent to three RCR123's.

I don't bother to use the RCR123's but love 18650's.

Same thing for me. If the light is regulated with a single cell 18650s are way better than 2 RCR123s.

They are also cheaper than 2 RCR123s ;)
 

tab665

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for an M20 go with cr123's (primaries not rechargables). i think selfbuilt did a review of the M20 with runtimes of the different battery configs. basically the 2x123 set up outlasted the 18650 on low and med modes. the 18650 did run longer on high mode. HOWEVER, it was only because the M20 is only semi regulated with the 18650, and it basically was only giving out about 80% of the lights total output with a rather steady decline down to 50% from start to finish... while the 2 x cr123 set up kept the light running at 100-90% all the way to the end of the battery life. so while you might be getting 3 hrs of runtime on high with a 18650, your certainly not getting 250 lumens.
so i guess my answer is niether RCR123 or 18650. go with the primaries.
 

Oddjob

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One 18650 is also safer to use than multiple cells. Li-Ion do have a low self discharge. IIRC I read a test where a Li-Ion cell kept it charge for a year or so. Can't recall about cold weather use though. Pretty good I think. Li-Ions do require a little knowledge to operate safely. Search around for info.
 

PhantomPhoton

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18650s are a far better way to do rechargeables for that size of light. Even when considering the slight efficiency hit from using a buck/boost circuit to fully regulate an 18650 one still gets noticeably more runtime at any power level. The only drawback that bothers me with 18650 (besides the size if you're looking for a short light) is the fact that plenty of light manufacturers don't properly regulate 18650 lights.
 

sygyzy

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How do you guys figure that 18650 is more powerful than 2 RCR123.

A 18650 may have more capacity (I don't know off hand) but it's also 3.7v vs 7.4 volts. I guess it depends on whether the light was regulated or not, right?
 

Marlinaholic

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The 18650 will run longer in most lights, but will be dimmer in most lights compared with two RCR123's as the voltage is so much lower with one 18650. Basically, some lights that are regulated at 6V become unregulated with the 18650 due to its low voltage, so you start out dimmer, and kinda gradually get dimmer as you go along, compared to 2 RCR123's. For instance, the DX R2 P60 drop in is dimmer with the 18650, as it requires about 6-7 volts for max brightness. However, the DX MC-E P60 drop in REQUIRES the 18650 (or just one RCR123) as it can't handle any higher voltage than about 4.2 volts. It all depends on what kind of light you are using when it comes the various rechargeables. If you have a narrow body light, 17650 is required, which has the same voltage as the 18650, but are rated at lower mAh so have reduced runtime, but if that is all you can fit in your light, that's what you are stuck with :shrug:
 
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kramer5150

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18650s are a far better way to do rechargeables for that size of light. Even when considering the slight efficiency hit from using a buck/boost circuit to fully regulate an 18650 one still gets noticeably more runtime at any power level. The only drawback that bothers me with 18650 (besides the size if you're looking for a short light) is the fact that plenty of light manufacturers don't properly regulate 18650 lights.

x2....

OP...
I have found both sizes to do a very good job at holding voltage. I have 10 16340 cells that were last charged ~2.5 months ago. Eight of them are holding strong at 4.10V, and two are at 4.09. FWIW my charger tops them off at 4.15.

Since migrating to 18650 I haven't even thought about reverting back to 2x16340. Its important however for the 18650 light to be properly regulated. A well regulated 18650 design can be just as bright as a 2x16340.
 
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Black Rose

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The 18650 will run longer in most lights, but will be dimmer in most lights compared with two RCR123's as the voltage is so much lower with one 18650.
It really depends on the design of the circuit in the light.

I have several Solarforce R2 5-mode drop-ins in my lights.

They have the same brightness whether powered by a 17670, 18650, or 2x16340 cells.
 

seaside

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RCR123A (16340) and 18450 both is the same Li-ion rechargable cell with diffference size and capacity. They should be the same in terms of reliability. CR123A, which is primary cell, will be bit more reliable and has better shelf life though, I don't think that will make life and death difference. And you mentioned RCR123A rather than CR123A... so..

As a minimalist I am, I like the small size of RCR123 as in EDC power source. But asides the size, 18640 is better in every aspects.
 

Wiggle

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How do you guys figure that 18650 is more powerful than 2 RCR123.

A 18650 may have more capacity (I don't know off hand) but it's also 3.7v vs 7.4 volts. I guess it depends on whether the light was regulated or not, right?

Say you have 2 RCRs at 700mAh each, and a 18650 at 2500mAh. The RCRs can be setup as 7.4V at 700mAh, but 7.4V * 700mAh is still a good bit lower than 3.7V * 2500 mAh. Basically the total energy in an RCR is less than half of that in an 18650.
 

fishx65

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How do you guys figure that 18650 is more powerful than 2 RCR123.

A 18650 may have more capacity (I don't know off hand) but it's also 3.7v vs 7.4 volts. I guess it depends on whether the light was regulated or not, right?

This is a good point which I didn't think about. I'm getting ready to make the jump to Li-Ion. I just ordered a Solarforce L2 and was gonna bore my 6P which is running a DX R2. Maybe I should change my plan to RCR123 instead of 18650. I want MAX brightness with these two lights. Will two RCR123's give me at least 1 hour of Max brightness with these?
 

PhantomPhoton

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A 18650 may have more capacity (I don't know off hand) but it's also 3.7v vs 7.4 volts. I guess it depends on whether the light was regulated or not, right?


Not true at all, really. Voltage doesn't matter with LEDs. White LEDs have VFs ranging from approx 3.2 to 4.0V. Easily driven by a quality buck boost circuit. The example you're thinking of is like I mentioned in my earlier post. A manufacturer not using a quality circuit designed for an 18650. 18650s can deliver more current than an RCR123 or 2x RCR123 too.
A properly regulated 18650 circuit can be brighter than a 2x CR123 on a pure buck. Look at Dereelights. The exception would be if you're wiring an MC-E in 2S2P. But if you intend to use an 18650 you just wire the MC-E in 4P and there's no problem.
 

Nimravus

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Looks like it's back to square one.

Guess I will use primaries for winter and maybe get a set of 18650 or RCR123 depending on manufacturers recomendations.
 

mdocod

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Here you go...

I remember participating in the answering of this question at least a dozen times, I don't even need to look at the results of the above link, I know the answers are there....

:)

-Eric

[PS] in most cases, if an 18650 is possible, it is preferable in many ways. While the output on many lights suffers in this configuration, the total stored energy and runtime on tap is much better than 2xRCR123s. A flashlight needs to be considered a tool, and sometimes, a tool becomes a survival tool. Runtime is very important here.
 
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johnny3073

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Looks like it's back to square one.

Guess I will use primaries for winter and maybe get a set of 18650 or RCR123 depending on manufacturers recomendations.

It's just me, but here's what I'd do. I would get a pair of really good 18650s and use them for everyday, keeping both topped off. Then I would keep a box of primaries for back ups.

So yes, in CPF fashion...get both :D.
 

kramer5150

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This is a good point which I didn't think about. I'm getting ready to make the jump to Li-Ion. I just ordered a Solarforce L2 and was gonna bore my 6P which is running a DX R2. Maybe I should change my plan to RCR123 instead of 18650. I want MAX brightness with these two lights. Will two RCR123's give me at least 1 hour of Max brightness with these?

No... none of the DX 2-cell modules will get you close to 60 minutes of run at peak brightness, when using 2x16340. Now... if you use 2x17500 cells in a 9P body, that should get you over the 60 minute hump.

If you are after 60 minute+ run times (from a pocket-able size host) you are going to have to go with an 18650 or 17670 setup. If you want that setup to maximize brightness off that one cell it will need a driver circuit optimized for single cell voltages. AFIAK none of the dual-cell DX modules run at peak brightness off a single cell.

Boring your 6P is a great idea. It addresses my biggest complaint about surefires in general. I got mine bored and couldn't be happier.
 
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