What is the purpose of IMR unprotected cells?

[midget]

Hey all, I have a newb question that I was curious about...


What exactly is the purpose/benefit of using an IMR cell? I have tried to do a little reading about what IMR means and here's what I am gathering..


- it is "safer" because it cannot be overcharged

- it may "drain" better.. does this mean it can provide more current safely comparatively to other rcr123a?

- it can be over-discharged and ruined forever


The batteries I'm thinking about are the AW IMR 16340's. Is there any practical reason why this battery might be preferred over any other protected RCR123a sized battery? I am currently using a sunwayman m10R (210 lumen version).

I am guessing that a conventional light like the SWM m10R wouldn't really benefit from an IMR16340 b/c it may not draw very high amperage, comparatively to say, some of the custom lights on this forum like those quads or triples or ones with fancy drivers. Am I correct?


Overall I'm just a little confused over the benefits of unprotected cells and whether or not I should care about them... I figured I'd ask the experts ;-)

 

[calipsoii]

They're a different chemistry inside. The chemicals don't explode aka "vent with flame" when mixed together liked LiCo's (RCR123) do.

Also, they can be discharged much faster making them good in high drain lights.

 

[midget]

They're a different chemistry inside. The chemicals don't explode aka "vent with flame" when mixed together liked LiCo's (RCR123) do.

Also, they can be discharged much faster making them good in high drain lights.

but most conventional lights that we know, such as the single 123a lights from fenix or sunwayman or quark or whatever aren't high drain lights, are they? these batteries are really best set for custom built lights that are driven for high output, no?



in other words. I have a sunwayman m10r and an IMR 16340. should i just take that IMR out and put in a normal protected cell because... all in all i'm not really gaining any benefit from it, am i?

 

[ChrisGarrett]

but most conventional lights that we know, such as the single 123a lights from fenix or sunwayman or quark or whatever aren't high drain lights, are they? these batteries are really best set for custom built lights that are driven for high output, no?

in other words. I have a sunwayman m10r and an IMR 16340. should i just take that IMR out and put in a normal protected cell because... all in all i'm not really gaining any benefit from it, am i?

You still have the 'safety' factor with IMR cells. In your case (and I have a V10R I just got,) you'll lose a little bit in capacity with the IMRs vs. Li-COs, but in the 16340 form factor, it's maybe 600mAh vs. 750mAh, as read on the labels.

I picked up a couple of protected 700mAh Soshine/Orbtronic 16340s to fiddle with in my SWM light, but ehhh...I'll probably get some AWs down the road. The Soshines w/case were $10 for the pair shipped and the AWs are closer to $7 ea, before shipping.

Smaller EDC lights won't generally peg the amps, where high drain cells like the IMRs will shine, but again, they're a bit safer.

Chris

 

[HighlanderNorth]

You still have the 'safety' factor with IMR cells. In your case (and I have a V10R I just got,) you'll lose a little bit in capacity with the IMRs vs. Li-COs, but in the 16340 form factor, it's maybe 600mAh vs. 750mAh, as read on the labels.

I picked up a couple of protected 700mAh Soshine/Orbtronic 16340s to fiddle with in my SWM light, but ehhh...I'll probably get some AWs down the road. The Soshines w/case were $10 for the pair shipped and the AWs are closer to $7 ea, before shipping.

Smaller EDC lights won't generally peg the amps, where high drain cells like the IMRs will shine, but again, they're a bit safer.

Chris

I just ordered 2 of those same Soshine 16340's about 5 days ago from Orbtronics. Haven't gotten them in yet. I'm not sure how good they are, or if they are really of any benefit to me versus RCR123's, as at least 1 of my lights CANNOT use 16340's or 123's, just 18650's. So the only light I currently have that CAN use 16340's is my 9v XM-L driven, 3 mode Thrunite/Solarforce L2P. I just found out that my Jetbeam BC-10 cannot use 16340's either.

Maybe I shouldnt have bought the 16340's in the first place!

 

[45/70]

- it is "safer" because it cannot be overcharged

Just a quick note here about IMR (lithium-Ion Manganese Round cells. Actually IMR cells are more easily damaged due to overcharge than traditional ICR (lithium-Ion Cobalt Round) cells. It's just that they are, as has already been explained, less likely to "vent with flame" or explode, when overcharged. One should be certain that the charger used to charge IMR cells has a maximum CV voltage within the allowable limits (4.20 Volts +/- 1%, or ~4.15-4.25 Volts), in order to prevent premature cell degradation.

Otherwise we seem to be on track here.

Dave

 

[midget]

so to conclude, are there any main performance benefits (other than safety) from running an IMR16340 vs a protected AW16340 in a commercial light like the SunwayMan V11R?


no, right? you get less runtime but a little more safety. they are only really good if you use a custom-type built light with really high drain.

what about the V10R's XM-L ones, the ones that are proposed output of 460+ lumens? is that considered "high drain?"

 

[MattSPL]

Here's the results of a test carried out by an ebay vendor who sells lithium cells. The AW IMR actually beat the AW 16340 protected cell. Has anybody compared the two?

 

[midget]

Has anybody compared the two?

this graph is about capacity (runtime) yes? it would be interesting to see actual comparisons in a single 123 light.



and for my *extremely* scientific comparison, here are two pictures i just took. At f/1.8 at 1/30s ISO400. range is like, 15ft.

light is a sunwayman V10R, XML on high. both batteries fully charged.

ICR cell:

IMR cell:

lololol pics look the same. this comparison doesn't help at all. i regret everything i have ever done.

 

[MattSPL]

Yes, more capacity(mAh) will mean more run time, but what is printed on the cell is often wrong.

I think you need to re-size your pics.

Cheers
Matt