KL1 on AAs?

I searched for a thread on this subject, but didn't see anything.

How well does a Surefire KL1 head work with 2 AAs in a Vital Gear FB3 body?

I've read that a E1L (same head) with a single R123 at 750mAH will run for around 45 minutes in regulation. Is it valid to assume that two 2500 mAH NiMH AAs (total of 5000 mAH) would run the KL1 for over six times as long in regulation? Over four hours regulated?

Are there issues with current draw that will undermine the runtime of the AAs? Is there something fundamental here I am missing?

I'm not certain about Gen4 KL1s but the older ones do fine on 3V from AAs or CR123s. Also remember that R123s are usually 3.7-4V which is a good bit more than the 1.2V per cell (2.4V for two) you'll see from NiMHs.

-LT

AA: 5Ah @ 1.2V = 3Wh
LiIon: 0.75Ah @ 3.6V = 2.7Wh

the AA's provide a bit more power, but at the kl1 is less efficient at the lower voltage

Is anyone actually running a KL1 on 2 AAs? As in a Vital Gear FB3 body? If so, can they share what kind of runtime they are getting?

BBH, Ah rating of two 2500mA AA, in series, is 2.5 Ah; that times 2.4 volts = 6 WH's. Sounds good, but like you said, in effect, KL1 needs more volts.

Bill

bonvivantmike said:

Is anyone actually running a KL1 on 2 AAs? As in a Vital Gear FB3 body? If so, can they share what kind of runtime they are getting?

Click to expand...

I have done so. It is less bright, and it pulls 0.67 amps @ ~2.4 volts (my lux is an H bin vf), so runtime should be at least 3.5 hours. It is pulling 1.6 watts to drive at 1 watt, so efficiency is pretty bad, ~62%.