Has anyone used these batteries in surefire's that are normally supposed to take two cr123's? If so, how did they do?
I have a current production 6px that I would like to use these in and plan on getting a 1000 lumen e2d defender that would also be nice with rechargeable cells. I don't know anything technical about lights or batteries and just want to make sure using these would be safe for the lights, batteries and myself. Would the runtime be better, worse or pretty much the same as using two 123a primary cells? What would be a good charger to use for the 16650's?
First off, I just want to say that you
should be fine with using your E2D with a 16650 (although you should do your research on the potential dangers of Li rechargeable batteries in flashlights and come to your own conclusion). That being said, my experience with the 16650 is on the SF Tactician (E2T-MV; 800 lumen with 2xCR123's).
I've used an Eagletac 16650 in my SF E2T-MV. Noticeably less lumen, but longer runtimes... albeit with even lower lumens as the cell discharges. @Jose Marin on this forum linked a written graph of his findings, and I find that my unofficial "eyeball" observations seem to mimic his findings (
link to Jose Marin's graph). I would assume that the SF E2DC might similarly have significantly lowerd output compared to fresh CR123's. I've since took the 16650 out of my E2T-MV and made it a dedicated "defensive emergency" light with primaries (2xCR123's) for longer term storage.
I would assume that you will have noticeably less lumen with a 16650 on your 1000 lumen E2D Defender, although it would still probably be considered very bright. I found that if I had my light stored for a few months and brought it out, the voltage drop from storage made it seem like it was running at around 60% output compared to a fresh set of CR123's, and around 80% output compared to the 16650 fresh off of the charger. For the record, I have the older E2D Defender LED (200-300 lumens maybe?), and with the same 16650 it seems to be only putting out like 50 lumens on high (eyeball guesstimate). For rechargeable, user replaceable battery lights, I've swayed away from SF, and dedicated my E2D (older version), E2T-MV, and EDCL2-T for situation specific emergency flashlights, and use other brands for general purpose lights for working, everyday, or sporting activites. I have considered taking the 2xCR123 heads, getting and using 1xCR123 bodies with a 16340, but it seems like a lot of bother and expense for lights that have compromised general purpose specs, while further compromising the tatical lumen parameters.
You have to remember that 2xCR123's is 6 volts (nominal), and 1x 16650 is 3.7 volts (nominal). So you're starting off with a lower voltage with the rechargeable 16650. I don't know how these lights will fair with 2x16340's (though 7.4v nominal) or 2xLiPo equivalents (6.4 volts nominal). I'm afraid it might damage the LED over time so I haven't tried it... I also don't own any LiPo batteries.
I'll add, that although I have not ordered CR123's from online dealers, a pack of 12 SF CR123's bought directly from Surefire is less than a similar 12 pack of Energizer of Duracell from the local HD (although I don't emeber shipping costs). Even Cabela's Streamlight batteries are sold at $7 for a 2 pack (more expensive $/cell than a 12 pack of Energizer, Duracell, or SF) if you are looking to pick something up locally.