3 V rechargeable CR123A batteries that are 34mm long? Leatherman Serac S3, 16340

fuyume

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I was typing a long post about this yesterday on my phone when the browser locked up and I lost the whole post, so let me try again.

I have a Leatherman Serac S3 (1xCR123A) that was my primary EDC light for several years, until in 2014, I moved to Northern New England, where it is apparently impossible to find CR123A batteries at a reasonable price, and I don't really have the money to order them in bulk online. Once I ran out of the stock of CR123As I had, I ended up buying an Inova X1 (1xAA) to be my primary EDC light. I hated that light because of the very poor UI, and earlier this year, I finally got around to replacing it with a Fenix E12 v2.0.

The thing is, even 13 years after it was released, the Leatherman Serac S3 still has a lot to recommend it, so I was hoping that I could either use 16340 batteries or a 3 V regulated rechargeable CR123A. According to a commenter here, although they tested a 16340 briefly without failure in a Serac S3, Leatherman customer service does not recommend using 16340 batteries in this device, and it being a long-discontinued model, I don't want to risk burning it out.

But the only 3 V regulated RCR123As I can find are those from KeepPower, and they are 36 mm long, compared to the 34 mm size of a CR123A. Although the Serac S3 might actually have enough room to accommodate them, I don't want to put undue stress on the circuit board or the spring, and either break something or render the spring useless for CR123A primary cells.

So, does anyone know of any 3 V regulated RCR123As that are actually 34 mm long? And why on Earth did KeepPower decide to make their RCR123A 2 mm longer than standard? I would have gladly dealt with slightly reduced capacity in order to keep the battery the "correct" size.

Alternatively, has anyone used a 16340 in a Serac S3 long term without failure? If I can't find a battery to use in my Serac S3, I will attempt to find a new home for it with someone who has an easier time finding reasonably priced CR123As.

The Serac S3 was originally rated for 7 lumens/36 hours, 43 lumens/4 hours, and 100 lumens/1 hour. Not terrible performance for a 2008 design, and I never felt limited by the runtime (I always carried a spare cell).
The E12 v2.0 is rated for 5 lumens/70 hours, 30 lumens/13 hours, and 160 lumens/1 hour, but of course that 160 peak lumens only lasts for about 30 min before falling off a cliff.

By contrast, the Fenix E18R (1x16340 or 1xCR123A, 2019 release), is rated for 5 lumens/70 hours, 30 lumens/13h50m, and 150 lumens/2h35m, plus has a Turbo mode of 750 lumens (which dims almost immediately to about 350 lumens and holds steady for probably 30 m before falling off the cliff, but these ratings are all with Fenix' "special" 3.7 V ARB-L16-700P Li-ion battery, which they apparently do not even sell separately. I don't generally tend to like forward clicky lights, but the fact that the E18R has a lockout mechanism make me feel a little better about it.

I don't really need another light or another battery type, but I am kind of torn between getting myself an E20 v2.0 or an E18R for Christmas. The only reason I'm even considering the E18R is because I could use rechargeables in it. If I do get the E18R, it would probably be my new EDC light, with the E12 being relegated to use cases where battery availability and lack of self-discharge in storage might be more desireable.
 

aznsx

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... but these ratings are all with Fenix' "special" 3.7 V ARB-L16-700P Li-ion battery, which they apparently do not even sell separately. I don't generally tend to like forward clicky lights, but the fact that the E18R has a lockout mechanism make me feel a little better about it.

I believe the 700P was fairly recently replaced by the 700UP, which is same as the 'P' but adds USB charging port, with I'm sure a slight increase in length. I think 700UP is considered the Fenix replacement cell for the 18R. I would expect no difference in performance / run time of the two cells. EDIT: BTW - I have and use several of the 700UP cells, and while I don't recall the tested capacity I got when new, I remember I was happy with the number and consistency. I haven't re-tested them after a period of use yet.

I know nothing about the (relatively) new 3-V regulated lithium ion cells you mention, but for several of my 1xCR123A lights I use the K2 Energy LFP123A cells (nominal 3.2V and 33.5mm length). You'd need an appropriate charger for those (CV=3.6V). I've seen a charger and 2 cells for $40 USD lately.

 
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Timothybil

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Lithium iron phosphate cells (LiFePO4) are a nominal 3.2v off the charger, which should be close enough to the CR123 3v to be useable. Can't speak to the length issues, but the 16340 is supposed to be a nominal size replacement.
 

hsa

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I would try Titanium Innovations cr123a. They are a buck apiece at Battery Junction. I've been running them in a Streamlight Polytac for 5 years and they work great.
 

Stefano

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I was typing a long post about this yesterday on my phone when the browser locked up and I lost the whole post, so let me try again.

I have a Leatherman Serac S3 (1xCR123A) that was my primary EDC light for several years, until in 2014, I moved to Northern New England, where it is apparently impossible to find CR123A batteries at a reasonable price, and I don't really have the money to order them in bulk online. Once I ran out of the stock of CR123As I had, I ended up buying an Inova X1 (1xAA) to be my primary EDC light. I hated that light because of the very poor UI, and earlier this year, I finally got around to replacing it with a Fenix E12 v2.0.

The thing is, even 13 years after it was released, the Leatherman Serac S3 still has a lot to recommend it, so I was hoping that I could either use 16340 batteries or a 3 V regulated rechargeable CR123A. According to a commenter here, although they tested a 16340 briefly without failure in a Serac S3, Leatherman customer service does not recommend using 16340 batteries in this device, and it being a long-discontinued model, I don't want to risk burning it out.

But the only 3 V regulated RCR123As I can find are those from KeepPower, and they are 36 mm long, compared to the 34 mm size of a CR123A. Although the Serac S3 might actually have enough room to accommodate them, I don't want to put undue stress on the circuit board or the spring, and either break something or render the spring useless for CR123A primary cells.

So, does anyone know of any 3 V regulated RCR123As that are actually 34 mm long? And why on Earth did KeepPower decide to make their RCR123A 2 mm longer than standard? I would have gladly dealt with slightly reduced capacity in order to keep the battery the "correct" size.

Alternatively, has anyone used a 16340 in a Serac S3 long term without failure? If I can't find a battery to use in my Serac S3, I will attempt to find a new home for it with someone who has an easier time finding reasonably priced CR123As.

The Serac S3 was originally rated for 7 lumens/36 hours, 43 lumens/4 hours, and 100 lumens/1 hour. Not terrible performance for a 2008 design, and I never felt limited by the runtime (I always carried a spare cell).
The E12 v2.0 is rated for 5 lumens/70 hours, 30 lumens/13 hours, and 160 lumens/1 hour, but of course that 160 peak lumens only lasts for about 30 min before falling off a cliff.

By contrast, the Fenix E18R (1x16340 or 1xCR123A, 2019 release), is rated for 5 lumens/70 hours, 30 lumens/13h50m, and 150 lumens/2h35m, plus has a Turbo mode of 750 lumens (which dims almost immediately to about 350 lumens and holds steady for probably 30 m before falling off the cliff, but these ratings are all with Fenix' "special" 3.7 V ARB-L16-700P Li-ion battery, which they apparently do not even sell separately. I don't generally tend to like forward clicky lights, but the fact that the E18R has a lockout mechanism make me feel a little better about it.

I don't really need another light or another battery type, but I am kind of torn between getting myself an E20 v2.0 or an E18R for Christmas. The only reason I'm even considering the E18R is because I could use rechargeables in it. If I do get the E18R, it would probably be my new EDC light, with the E12 being relegated to use cases where battery availability and lack of self-discharge in storage might be more desireable.
I did not like the beam of the new E12, I returned the light (I preferred the wide beam of the old E11) but you can use the E12 as an emergency flashlight
I would go with the new E18R, original or commercial rechargeable batteries are widely available
 

John_Swisher

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You might also look at the Nitecore MT10C. It uses 18350 or R(CR123a) batteries. I have been really pleased with mine.
 

aznsx

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I believe the 700P was fairly recently replaced by the 700UP, which is same as the 'P' but adds USB charging port, with I'm sure a slight increase in length. I think 700UP is considered the Fenix replacement cell for the 18R. I would expect no difference in performance / run time of the two cells. EDIT: BTW - I have and use several of the 700UP cells, and while I don't recall the tested capacity I got when new, I remember I was happy with the number and consistency. I haven't re-tested them after a period of use yet.

I know nothing about the (relatively) new 3-V regulated lithium ion cells you mention, but for several of my 1xCR123A lights I use the K2 Energy LFP123A cells (nominal 3.2V and 33.5mm length). You'd need an appropriate charger for those (CV=3.6V). I've seen a charger and 2 cells for $40 USD lately.


After some thought: If you decide to go with the K2 cells, I'd recommend buying the cells (~$8 ea), but instead of buying the K2 charger, I'd recommend buying a XTAR VP2 instead. It's a very good charger (relatively speaking), and although discontinued is still available. It is far more versatile than the dedicated K2 charger, and can be bought at about the same cost (if not less). I use the VP2s for most all my lithium ion charging, and can recommend them.

I would also add that while I know little about the referenced 3V regulated lithium ions, I do understand that they have RFI issues. I think I recall your mentioning working around audio systems, and you wouldn't want to introduce a bunch of RFI into that environment.
 

fuyume

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I would also add that while I know little about the referenced 3V regulated lithium ions, I do understand that they have RFI issues. I think I recall your mentioning working around audio systems, and you wouldn't want to introduce a bunch of RFI into that environment.
Hmm, I had not heard that they have RFI issues, but that's a good thing to look out for. Thanks for that tip.
 

fuyume

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You might also look at the Nitecore MT10C. It uses 18350 or R(CR123a) batteries. I have been really pleased with mine.
I've been looking into Nitecore this week, and some of their products are pretty impressive. I just might pick up one or two.
 

fuyume

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I was looking at my Serac S3 again last night, and comparing it to my E12 v2.0, as well as the size specs compared to the E18R, and I realised the E12 v2.0 is almost as large as the S3, while the E18R is 20 mm shorter than the S3. However, the S3 has a notably deep reflector, which is probably why I have always been impressed with the Serac S3 on the occasions when I have used it at max power to search at night. That 20 mm difference in length is entirely the reflector assembly.
 

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