AW 18650 better for TK11 than AW 123's?

hatman

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Is there an advantage in using one of AW's R18650 2600mah batteries in the TK11 instead of two AW 123's?

Can the 18650 be charged in the Pila and Ultrafire chargers?

Thanks,
 
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hatman

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Well, here's part of the answer to my questions, from the specs for the TK11R2 found on the 4Sevens website:

Turbo Mode: Constant 240 Lumens
2.7 hours (one 18650 Li-ion battery)
1.5 hours (two CR123A batteries)
General Mode: Constant 64 Lumens
12 hours (one 18650 Li-ion battery)
10 hours (two CR123A batteries)


Yikes -- that's a pretty decent bump in runtime from using the 18650!

So now my questions are:

-- I have no experience with the 18650. Is there any DISadvantage to using it over the 123s?

-- And can the 18650 be charged in the Pila and Ultrafire 139 chargers?

Thanks,
 

Often Confused

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Hatman:

I'm pretty new to the forum, but happened to stumble across your question here.

The point I bring up (we might both appreciate a solid answer) is that Fenix does not specifically list the TK-11 for use with RECHARGEABLE 123A's (see their specs page at http://www.fenixlight.com/viewproduct.asp?id=92)

Conventional lithium (lithium cobalt, I believe?) rechargeables supply 4.2 volts fully charged. This means that one 18650 is fine (and specificied as OK by fenix). Two disposable 123A's equals about 6 volts and Fenix specifically approves that battery option too, but two rechargeable 123A's would supply 2 x 4.2=8.4 volts - perhaps more than the light is intended to handle?

On the other hand, I have seen reviews that have tested runtime with the rechargeable 123As. Probably something to look into before using the TK-11 a whole bunch with RCR123A's (I personally use an 18650 - I believe the TK-11 is "unregulated" with an 18650 so output is a little lower to start with and fades with discharge, but for me the much longer runtime is well worth it and the fading brightness provides some warning with respect to a weak battery).

I'm interested to see what others think about the TK-11 + RCR123A issue.

Tim
 

LEDite

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Hatman;

The #18650 lithium-ion batteries are the most developed rechargeable we have.

Millions of them have been produced to power notebooks.

This has accelerated the improvements in power density and reliability ...

at least among Japanese manufacturers.

LEDite
 

hatman

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Hatman:

I'm pretty new to the forum, but happened to stumble across your question here.

The point I bring up (we might both appreciate a solid answer) is that Fenix does not specifically list the TK-11 for use with RECHARGEABLE 123A's (see their specs page at http://www.fenixlight.com/viewproduct.asp?id=92)

Conventional lithium (lithium cobalt, I believe?) rechargeables supply 4.2 volts fully charged. This means that one 18650 is fine (and specificied as OK by fenix). Two disposable 123A's equals about 6 volts and Fenix specifically approves that battery option too, but two rechargeable 123A's would supply 2 x 4.2=8.4 volts - perhaps more than the light is intended to handle?

On the other hand, I have seen reviews that have tested runtime with the rechargeable 123As. Probably something to look into before using the TK-11 a whole bunch with RCR123A's (I personally use an 18650 - I believe the TK-11 is "unregulated" with an 18650 so output is a little lower to start with and fades with discharge, but for me the much longer runtime is well worth it and the fading brightness provides some warning with respect to a weak battery).

I'm interested to see what others think about the TK-11 + RCR123A issue.

Tim

Often Confused,

You don't seem at all confused; I'm the one who missed that.

Yes -- may we please hear from others about using the TK11 with RCR123As?

Meanwhile, I think I shall be ordering a couple of 18650s!
 

Black Rose

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Yikes -- that's a pretty decent bump in runtime from using the 18650!
RCR123/16340 cells only have about 650 mAh capacity (don't believe the elevated capacity numbers you see on eBay) whereas 18650 cells usually have 2200 mAh or more capacity.

As Oftern Confused mentioned, you'll get more voltage from a pair of RCR123/16340 cells, but the capacity is low.
On the flip-side, you'll get less voltage (3.7 - 4.2) with an 18650 but you gain a lot of capacity.

-- And can the 18650 be charged in the Pila and Ultrafire 139 chargers?
Yes they can be charged in both.
 

Often Confused

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Hatman,

I think you'll like the 18650's. I have a couple RCR123A's and I sorta regard them as a "necessary evil". Now THAT may be a bit strong - but what I mean is that they are very useful for routine use in smaller diameter lights that simply won't take the 18650. Many such lights could also be powered by a single "17670" but the difference in capacity between a 17670 vs. 2xRCR123A isn't that huge and the higher voltage of 2xRCR123As will keep most of these lights in regulation for most of the battery life. Of course, one must use care to employ them only in lights that can take the higher voltage relative to a pair of disposables - precisely the question we have about the TK-11.

I never really "investigated" the TK-11/RCR123A question in any detail because - since the light will take an 18650 - that is what I use. One of the review sites shows a runtime plot with RCR123As in the TK-11, but my worry is possible long-term degredation of the light if it really isn't designed to take the higher voltage.
 
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