Can IMR cell be used when a protected cell is required?

[DHart]

I see that some flashlight specifications state that use of a protected cell is required... does that rule out the use of an AW IMR cell?

For example, the Fenix TK11 specifies a requirement of a "protected" 18650 cell. Does this mean that one cannot successfully use an AW IMR18650 in this flashlight?

Thanks, in advance, for the help.

 

[Raoul_Duke]

No, But the length may be a few mm shorter, so contact issues may happen, and if you drain the cell fully it won't work again, but you can pull so much more current from IMR you should use a high current Lamp/ Led(s) with the cells.

 

[DHart]

No, ...

Meaning no, I can't use the IMR cell or no, meaning it won't be a problem except perhaps for possible length and drain issues?

I have some AW IMR 18650s on order, so I guess I'd better change that to AW protected 18650s. I didn't understand the high current difference.... I need to learn what demands high current and what doesn't.

 

[gswitter]

Meaning no, I can't use the IMR cell or no, meaning it won't be a problem except perhaps for possible length and drain issues?

Meaning you can do it, but it's a bad idea.

If you use an unprotected cell (like the IMR18650) in a regulated light without a low voltage cut-off (like the TK11), you will likely over-drain and damage the cell, because there will be no visual indication when the cell is nearly depleted.

 

[DHart]

Ok... thanks very much for that clarification. I was just thinking about buying a TK11 and noticed the advisory to use only protected cells with them.

As I understand it, with a protected cell and especially an unprotected one, like the IMR, recharging WELL before depletion is a very good idea for good battery life and safety. The hazards and dangers of over-depletion and over-charging Li-Ions are something I am now well aware of. I have some IMR cells on order for use in other applications and will be certain to pull them from use for recharging earlier-on, rather than later-on. Thanks again.

 

[Kestrel]

If you haven't noticed this current thread, it might give you some useful info.
http://www.candlepowerforums.com/vb/showthread.php?t=218321
Ah, I see that you've posted in it. FWIW post #14 has _a lot_ of what you need to know for your setups.

Also, mdocod's rechargeable/LED guide is a fantastic resource:
http://www.candlepowerforums.com/vb/showthread.php?t=201375
His other guide also gives some useful background info, although some of the info is incan specific rather than LED:
http://www.candlepowerforums.com/vb/showthread.php?t=161536

 

[mdocod]

The TK11 is not regulated on an 18650 very well, so you would probably see some dimming when the cell really started to get down to it....

But the bigger question would be "why bother?"

Why mess with an unprotected cell that you have to babysit more closely, while at the same time take a 30% hit on runtime compared to a regular protected cell? IMR cells excel in high drain applications. Like custom incandescent scorchers that run for 15 minutes and light things on fire.

 

[DHart]

The TK11 is not regulated on an 18650 very well, so you would probably see some dimming when the cell really started to get down to it....

But the bigger question would be "why bother?"

Why mess with an unprotected cell that you have to babysit more closely, while at the same time take a 30% hit on runtime compared to a regular protected cell? IMR cells excel in high drain applications. Like custom incandescent scorchers that run for 15 minutes and light things on fire.

Now I know better!@ Thanks for the education. I guess I really don't have any need for IMR cells. Thank you. I needed that!