AA Lithium vs CR123 Lithiums ?

[5Sport]

Is there a big advantage of one type of battery over the other, now that AA Lithiums are out?

I have a bunch of surefires (CR123's) and have always depended on them for work. Now that I have found this forum and recently purchased a Fenix TK20 (What a great light), I can obviously use lithium AA's in them without the fear of leaky alkalines.

So which type of battery is better for light ouput and run time? Are CR123's still better that AA's, or do the new AA Lithium/flashlight combos make CR123's old technology.

Sorry, I'm new and trying to learn. Please use small words and speak slowly, some of the technical stuff on this forum makes my head hurt.:o

 

[Oddjob]

Some prefer the form factor of one over the other. AA's will give you more runtime but CR123's can provide more power so the driver does not have to boost the voltage necessary to provide high output. I think with the evolving technologies the only differences will be the size and runtime. My knowledge is limited so I'll defer to those who know more.

 

[45/70]

Just a couple of quick points. While both AA and CR123 lithium cells are lithium chemistries, the composition is different. AA's are Lithium Iron Disulfide and CR123's are Lithium Manganese Dioxide. This gives the CR123's a slight advantage.

CR123's are capable of delivering a little more actual power under load than the AA lithium's, while having a similar effective capacity. And as Oddjob pointed out, the 123's overall form factor is more compact, being considerably shorter in length, and only slightly larger in diameter.

I don't believe CR123's will be taking a backseat to the AA variety very soon. Each type serves it's purpose well.

Dave

 

[dudemar]

Another advantage is Energizer L91s (Ultimate Lithium) have a 15 year shelf life, vs CR123's 10 year shelf life.

 

[5Sport]

So what I'm gathering is that CR123's are more powerful and have a longer run time, but does that justify the higher cost and availability?

Or, is their overall performance that much better?

I ask as I am trying to decide which light to carry. If the AA's can get pretty close to the performance of the CR123's, I might focus on AA lights. The TK20 is my first high performance AA LED, and if other lights are equal to or better than that one, I may have to rethink my Surefires.

Thanks and sorry for the questions.

 

[Marduke]

Remember that many (not all) 1xAA lights also accept 14500 cells, which gives you the same output and longer runtime than equivalent RCR123's (16340's).

 

[Henk_Lu]

Remember that many (not all) 1xAA lights also accept 14500 cells, which gives you the same output and longer runtime than equivalent RCR123's (16340's).

I'm new to li-ion, still haven't got the cells I ordered... :candle:

Most RCR123 I saw have 750mAh, the 14500 also. If I understand right, the 14500 has the same output with longer runtime?

There are CR123A lights you get with an extender (Dereelight C2H, Jetbeam Raptor RRT-0...) which accept both the RCR123 and the 14500. I don't have any extenders and thought I would get exactly the same with the RCR123, but at a smaller size? What if I take RCR123 with 900mAh (like the ones from batterystation)?

 

[Marduke]

Even though 16340's and 14500's have the same printed capacity, 14500's almost always give a longer runtime.

Don't blindly believe the capacity on the label. They can print whatever number they want on there.

 

[45/70]

Marduke is correct. In my experience, good 14500's have about 700mAh at typical flashlight loads, and RCR123's about 600mAh, regardless of what's printed on the label. Again, this is with "Good cells". Most of the lesser quality cells don't do as well in either format.

Dave

 

[5Sport]

Ok guys. Thanks for the responses, but you are making my head hurt. I had to look up what 14500 cells were and I'm still not sure.

Let me ask you this. If I use my TK-20 with lithiums, and I compare it to a Surefire C3 or a P6 with a LED drop in, which would be the better light. Good throw, long run time, and reliability. Either using the surefire drop in, or the 6076 from Dealextreme. I ordered the drop in from dealextreme, but haven't received it yet.

Sorry if I'm slow

 

[Henk_Lu]

I hope you mean L91 by lithiums for the TK20?

I don't know its specifications, but I doubt it can handle 8,4 Volt of two 14500, if that's what you have in mind...

EDIT : OK, I re-read the thread and you obviouly mean L91! The TK20 is neutral white, I like it. You can't compare it to other lighs which are cool white.

 

[vali]

Keep in mind the voltage difference between 14500 li-ion and lithium primaries. If you use 2x14500 li-ion in a TK20 you will fry it.

 

[Billy Berue]

I had to look up what 14500 cells were and I'm still not sure.

It's a rechargeable Li-Ion cell with the same [approximate] dimensions of a traditional AA alkaline cell. They have nominal voltage of 3.7v, but they typically come off the charger around 4.2v. Packs considerably more punch than its alkaline or NiMH counterparts.

 

[Pekka]

Keep in mind the voltage difference between 14500 li-ion and lithium primaries. If you use 2x14500 li-ion in a TK20 you will fry it.

It might survive single 14500 with a spacer althought I'm not trying that on mine... :rolleyes: