Best LiFePo R123 combo pack for Super Tac?

jabe1

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A friend asked me to find him 4 LiFePO R123 (3v) and a nano charger for cheap, where is the best deal? He'll be using them in a SL Super Tac.
 
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Re: Best LiFePo R123 combo pack?

I'd be tempted to run it on a protected 17670 LiCo instead to get better runtime, LiFePO4s are really going to stink in the runtime department (might give 30 minutes give or take). A 17670 should go well over an hour, but won't have regulated output through the discharge...

I did some searching around and can't dig up anything confirming whether it can handle the voltage from a pair of 3.7V cells... wish I had the answer to that as a pair of protected LiCo RCR123s would give about double the runtime compared to LiFePO4 clels.
 
Re: Best LiFePo R123 combo pack?

I'd be tempted to run it on a protected 17670 LiCo instead to get better runtime, LiFePO4s are really going to stink in the runtime department (might give 30 minutes give or take). A 17670 should go well over an hour, but won't have regulated output through the discharge...

I did some searching around and can't dig up anything confirming whether it can handle the voltage from a pair of 3.7V cells... wish I had the answer to that as a pair of protected LiCo RCR123s would give about double the runtime compared to LiFePO4 clels.

Thanks, that's where my thoughts led me. Can't believe SL has no voltage specs on this thing!
 
Re: Best LiFePo R123 combo pack?

If someone who owns one of these had a bench power supply, or knew someone who had one that they could barrow, then we could find out for sure whether the circuit could do it.... Just slowly ramp the voltage up from ~6V starting, and see if the current continues to fall, if it makes it to ~9V with the current ~500mA then it should be fully supportive of a pair of RCR123s....

I'm quite confident that without said testing above, it would probably be the best compromise to go with the 17670 :)

Eric
 
Re: Best LiFePo R123 combo pack?

It should have a Buck circuit, so the determining factor would be which resistors it has? I have dropped an e-mail to SL, hoping they will get back to me. I was very specific about what I would like to do and questioned them about voltage ranges for this circuit. We'll see.
 
Re: Best LiFePo R123 combo pack?

In a true regulating buck circuit, a sense resistor is often involved to set the output current, but that has very little if anything to do with what input voltage it can handle.

They will tell you only to use CR123 primary cells as any other cell could damage the flashlight and void the warranty.
 
Re: Best LiFePo R123 combo pack?

They will tell you only to use CR123 primary cells as any other cell could damage the flashlight and void the warranty.
jzmtl has or had a Super Tac.

He sent a message to SL about using rechargeables in it and that is pretty much the response he got back.

He mentioned that in his review thread.
 
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