Streamlight TL2-X battery options

rwolfenstein

Enlightened
Joined
Mar 29, 2017
Messages
566
I was trying to research to no avail. Can an LED TL2 or TL2-X run a 14500 battery? I know an 18650 battery wont fit in the body as its about the same diameter is a surefire E series. I was just wondering if anyone knows.
 

aznsx

Flashlight Enthusiast
Joined
Apr 24, 2015
Messages
1,747
Location
Phoenix, AZ USA
I was trying to research to no avail. Can an LED TL2 or TL2-X run a 14500 battery? I know an 18650 battery wont fit in the body as its about the same diameter is a surefire E series. I was just wondering if anyone knows.
I wasn't familiar with those lights, but did look up the info on them. This is my guess / speculation / opinion.

These are 2XCR123A lights. I believe you will find that the only practical option for usng secondary / rechargeable cells in those lights would be (physical size) 16x34 mm (16340) / CR123A size cells of LFP / lithium iron-phosphate / LIFePO4 chemistry. They are available from Surefire (which are probably good), K2 Energy (which is the brand I personally use), and a few other manufacturers (some of which I won't recommend but could be OK). Their output is ~3.2V, and they are charged to a CV / terminating voltage of 3.6V. You will need a charger which can accommodate them. The cells will cost ~$7-8 each in either case.

Here are the Surefire cells:


You'll find a charger from Surefire at the bottom of that page.

To find the K2 cells, search for 'k2 energy LFP 123A. I have bought these from a couple of different places, most often 'batteriesinaflash'. K2 also sells a 2-bay charger specifically for them (which I believe is also available from 'batteriesinaflash'.

Here's the spec sheet for the K2 cells: I can't figure out how to attach a .pdf file, so here's a small screen capture:

Screen Shot 2023-07-15 at 1.54.41 PM.png

Here's a capture of one of the chargers K2 sells:
Screen Shot 2023-07-15 at 1.57.11 PM.png


The charger(s) I use for such cells (of any brand) are these, and they work well, and can also do other Li-Ion cells besides. This is a good source I have used, but the info they list for it is somewhat incomplete; these support several more cell sizes than those listed here:


These are my recommendations, and are what I use in all my EDIT: LED lights designed for CR123A. Relative to 'throw away', primary CR123A, such cells will provide very good outright performance, but with more limited run-time (due to their lower capacity)
 
Last edited:

fivemega

Flashlight Enthusiast
Joined
Jan 28, 2003
Messages
5,550
Location
California
I was trying to research to no avail. Can an LED TL2 or TL2-X run a 14500 battery? I know an 18650 battery wont fit in the body as its about the same diameter is a surefire E series. I was just wondering if anyone knows.
These may work for your flashlight.

Edited: too long to fit.
 
Last edited:

aznsx

Flashlight Enthusiast
Joined
Apr 24, 2015
Messages
1,747
Location
Phoenix, AZ USA
These will work perfectly for your flashlight.
Are these of the typical design which result in 'sudden death' when discharged (as in a perfectly straight vertical line on the output graph when they hit discharge limit)? If not, I may try them, although they're a bit longer that the K2 cells I use. The K2s discharge very gracefully and don't leave me suddenly in the dark. I have an issue with sudden, unexpected total darkness when using a flashlight. YMMV, and all that rot.
 

fivemega

Flashlight Enthusiast
Joined
Jan 28, 2003
Messages
5,550
Location
California
Are these of the typical design which result in 'sudden death' when discharged (as in a perfectly straight vertical line on the output graph when they hit discharge limit)?
All protected batteries are like that or will be destroyed in case of over discharge.
If you don't want to be in dark, simply get extra set of batteries or get a
26650 flashlight which has much longer run time per charge.
Capacity of each 26650 is 5500mAh compare to capacity of 550mAh rechargeable 123 which will run almost 10 times longer per single charge.
 

aznsx

Flashlight Enthusiast
Joined
Apr 24, 2015
Messages
1,747
Location
Phoenix, AZ USA
All protected batteries are like that or will be destroyed in case of over discharge.
If you don't want to be in dark, simply get extra set of batteries or get a 26650 flashlight which has much longer run time per charge.
Capacity of each 26650 is 5500mAh compare to capacity of 550mAh rechargeable 123
I'm not in need of a new solution; the OP is.

I have no issues with the LFPs I'm using, but wanted the OP to be aware of this 'feature'.

My K2s are not protected, but because they're LFP, I can make an exception; tradeoffs, as always. They can also be safely, routinely discharged to a lower voltage than some other chemistries (2.5V being no big deal at all), and that, along with a final discharge curve which does not terminate in a vertical line, makes them quite usable for me in practice.

Other protected cells do indeed shut off suddenly when their overdischarge protection kicks in (and are generally all I use when appropriate / possible); however the primary point here is that their voltage decreases as they discharge, and depending on the light, that often provides me with some advance warning of the impending event. Those lights may also provide their own advance warning as well (which does not mean shutting off abruptly). In my case, some warning is far, far better than zero.

Sudden, total darkness can put my safety at risk in my line of work ('heavy' industrial environment, with safety risks being routine). Backup cells / lights are of no value after I'm already been put in a bad situation (like injured or killed). I don't know how you use your lights, but I believe the OP is a LEO, and their needs may be more in line with my own, so my perspective may be applicable to them.

I don't just recommend based solely on my own needs, but when possible, try to consider the needs of the OP.

The lower capacity is indeed a tradeoff, but works fine in my application. No issue. I can plan around that known.

These things shouldn't be over-simplified, and there are several factors in play, and they must be considered in their totality. Engineering is always about prioritized tradeoffs, not just isolated facts. My post was for the benefit of the OP. I realize you've already determined the optimal solutions for your personal apps. The OP likely has not.

Hope that clarifies my points for you, and more importantly, the OP.
 
Last edited:

Winter Medic

Newly Enlightened
Joined
Sep 12, 2021
Messages
8
Location
PA
This might already be covered else where but my questions seems in line. Can the LPS from sure fire (the 3.2 volts) be used in the Streamlight ProTac 2L for a voltage perspective ? I cant seem to find a documented safe voltage range on the streamlight website for the input. The ProTac 2L is right size I like to carry, but I really would like a rechargeable options vs the C123 (3volts per). Would an extra 0.4 total volts put the light at risk? I have some of the SureFire which ill try for sizing later but the voltage thing could be the deal breaker lol.

Thanks for the input in advance!

Adam
 

fivemega

Flashlight Enthusiast
Joined
Jan 28, 2003
Messages
5,550
Location
California
I have tested single 16650 in Streamlight LED TaskLight 2-L and works perfectly.
As I mentioned somewhere else, for incandescent TL-2, Nightfighter and Scorpion, single 16650 will work fine with Strion bulb.
 
Last edited:

Winter Medic

Newly Enlightened
Joined
Sep 12, 2021
Messages
8
Location
PA
I have tested single 16650 in Streamlight LED TaskLight 2-L and works perfectly.
As I mentioned somewhere else, for incandescent TL-2, Nightfighter and Scorpion, single 16650 will work fine with Strion bulb.
Great. I'll give it a shot. Thanks for the response!
 
Top