Surefire LFP 123A lithium-phosphate rechargeable batteries

[snakyjake]

I purchased K2/Surefire because of Surefire's backing and K2's extensive testing. Most of all, K2's customer service has been extremely responsive of my concerns and providing me data.

 

[sidecross]

Tenergy LiFePO4 123A's claim "750mAh" and have minimum capacity 450mAh, but K2 Energy LFP123A's are 600mAh with minimum capacity 550mAh. Even if they do come from the same manufacturer, the cells aren't made to the same specifications.

I've never heard of K2 Energy before SureFire came out with the rechargeable kit, so I had looked into Tenergy LiFePO4 123A's. Based on the number of complaints about dead cells and reliability issues, I decided not to take the chance.

It is my understanding that the standard Surefire 123C is about 1300mAh while the Tenergy LiFePO4 is 750mAh.

I have just tried the Tenergy batteries and they have worked, but I would rather use the higher capacity Surefire's.

 

[Robin24k]

It is my understanding that the standard Surefire 123C is about 1300mAh while the Tenergy LiFePO4 is 750mAh.

With current technology, it's simply not possible for the 750mAh to be an accurate claim. Printing 750mAh on the batteries is pretty shady because according to the datasheet, they are only 450mAh...

 

[sidecross]

With current technology, it's simply not possible for the 750mAh to be an accurate claim. Printing 750mAh on the batteries is pretty shady because according to the datasheet, they are only 450mAh...

Thank you for the update on the claimed 750mAh information.

 

[write2dgray]

I've tested both companies cells for 5+ years. K2 is a reputable manufacturer. Tenergy rebrands different factories' cells for different product lines.

 

[Viking]

I saw a graph in another thread between K2 , Tenergy and AW's LFP batteries. Unfortunately I can't remember which thread :-(


But according to the graph, there were indeed more mah in the K2 cells , than the other two brands.
I think it was about 30 pct or so.


AW and tenergy was almost identical , with a very slight advantage for AW.


But remember also the K2 batteries costs twice as much as the tenergy's ( $ 6,- vs. $ 3,- each ).


I would recommend tenergy over K2. Because I don't think their performance justify the big price difference. unless little more mah is very important for some specific reasons.


The batteries cycle life was not part of the comparison however.

 

[N8N]

I looked up the datasheet for the K2 123A cell, and it says the max charging voltage cutoff of the cells is 4.2V not 3.6-3.7 as I would expect.

Has anyone tested the K2/Surefire charger and can you tell me at what voltage it terminates?

I'm seriously considering picking up a few of these cells in an attempt to get better UV performance out of my Streamlight Night Com UV relative to a single 17670, but I have this nasty habit of OCD style researching every purchase in an effort to get the highest quality/best value products.

 

[Robin24k]

From memory, I recall that the K2 charger cutoff at 3.65V. Lithium-phosphate can be charged to 4.2V, but it will reduce cell life.

 

[snakyjake]

I looked up the datasheet for the K2 123A cell, and it says the max charging voltage cutoff of the cells is 4.2V not 3.6-3.7 as I would expect.

4.2v is the max. 3.65v is the recommended cutoff.

 

[N8N]

Well, I just gave up and ordered... no local SF dealers have them to look at and I couldn't find a less expensive web source of the K2 cells, so I just ordered the kit off SF's web site. Will give my thoughts when I get them, although I don't really have a good method of checking capacity (no hobby charger at this time)

 

[jkingrph]

Why are CR123a rechargeable batteries not recommended for Surefire flashlights, on the LFP 232a types.?

 

[Robin24k]

Most rechargeable 123A's are lithium-ion, which are 3.7V and may be too high for some lights.

 

[snakyjake]

My guess:
Lithium cobalt is dangerous. There's a protection circuit that can be damaged. The protection circuit cuts off the light when voltage is low.

I've been using K2/Surefire LFP for a year now, and I get plenty of runtime. I also like that the light doesn't cutoff on me. And the chemistry is completely safe from overcharging/discharging.

In my real use, LFP's advantages are way more than what LCO gives. I won't compromise safety.

 

[GoVegan]

Did anyone else notice that SureFire stopped selling the K2 LFP 123A rechargeable batteries recently, they no longer appear in the "Parts and Accessories" links below each LED flashlight, in fact even the following URL no longer works:

http://www.surefire.com/2-pack-lfp123-rechargeable-batteries.html

My understanding was that they were popular, so does anyone have a definitive reason why, i.e. has anyone emailed Surefire?

 

[Phlogiston]

I don't use them, so didn't pay much attention at the time, but it's been discussed on CPF here and here.

 

[thospress]

Did anyone else notice that SureFire stopped selling the K2 LFP 123A rechargeable batteries recently, they no longer appear in the "Parts and Accessories" links below each LED flashlight, in fact even the following URL no longer works:

http://www.surefire.com/2-pack-lfp123-rechargeable-batteries.html

My understanding was that they were popular, so does anyone have a definitive reason why, i.e. has anyone emailed Surefire?

Surefire Customer Service advises that Surefire is looking for a different manufacturer, and that the replacement rechargeable batteries would be available on the website although unsure when. My guess is that inventory supplies were erratic.