I’m looking for a light to leave in the car with a baggie of CR123A cells. I’m looking for a 2*CR123A light minimum. More cells would be fine but 1 is too little capacity. This is to function as an emergency light. I’m not looking to spend over $40 and less is better. I do want to have a reliable light though.
Is it safe to substitute CR123A batteries in most 18650 lights, or does the driver need to support it?
I notice that on http://flashlights.parametrek.com some lights like the Thrunite TN12V4 are listed as being compatible with CR123A lights but I see no mention of it on the official product page.
Thanks!
EDIT: I’d prefer it if the light can take CR123A OR 18650 batteries. That way I could potentially swap my 18650 out of a hotrod EDC light and get a ton of runtime from the emergency light in an emergency where runtime mattered more than quantity or quality.
What’s driving you to go with CR123A versus 18650? Is the idea to have CR123A vs. RCR123, so they’re one-time-use disposable cells? Or do you have a boatload of CR123A cells that you just want to use up?
Since this is considered a spare light, you could check the used market for an older flashlight and save a good bit. Olight, Nitecore, and Fenix have had a lot of 2xCR123 lights in the past. But then again, you could go with a new “Convoy S2“:https://www.banggood.com/Gray-Convoy-S2-SST40-1800lm-5000K-6500K-Temperature-Protection-Management-18650-Flashlight-p-1546416.html with SST-40, for $23… and it handles both 2xCR123A and 18650.
There’s an inherent danger in using series-connected cells, even a pair of ’123s. I had a pair go China Syndrome in my MH20, enough to melt the wraps. Both ended up sub-volt by the time I got ’em out, so nfi what happened. And the light was off, sitting on a table, minding its own business.
No matter what, they won’t drain perfectly in sync, and the runt of the litter will go dead first, probably start reverse-charging, and then all sorts of Bad Things will happen. Maybe even just sitting around.
If you insist on going the bag o’ batteries route, keep the light empty, and only load it when you need to.
That said, most Nitecores do 18650 or 2×’123, a bunch of newer Sofirn and Wurkkos, etc.
I live in an area where subzero temperatures during the winter are normal. I’ve read that primary lithium cells offer the best performance in those conditions. I’ve also read that 18650s do not perform the best in cold. If I really want to leave the light in the car all year then CR123A cells seem like the best solution to me. This truly would be a backup light too. I already EDC an 18650 light.
Thanks for the heads up on the Convoy model. I’ve been meaning to buy a Convoy one of these days. Might just go with that.
It’s funny, I recently ordered a Sofirn SF47 which has two 21700 cells in series. I didn’t even really think about that. I plan to charge the batteries in good charger though so I should be able to detect a cell dying (hopefully)
What type driver does this S2+ have? I ask because there is no mention of 2xCR123A compatibility in the link. Wouldn’t it need a buck driver like a Sofirn SP32A to handle both?
You live in Florida so the coldest it gets like like 30 degrees F. Where I live it dips down as low as –20 degrees F basically every year and can easily go lower. Lithium primaries should outperform an 18650 in our winters.
I’ve kept a Surefire G2X PRO in a GHB in my work vehicle for the last 5 or 6 years, all 4 seasons, loaded with SF branded CR123’s with no issues. Even though it’s a mechanical clicky, I do the tail cap lockout to prevent accidental activation in the bag. I swap new in batteries once a year or so, and use the rotation set individually in my Malkoff MDC HA. I always use new batteries from the same batch, and meter the voltages prior to installing. Gifted one to my son years back for the same purpose. He’s still alive.
If it’s subzero all day long, but really even just for 10-12 hours overnight, I’d be inclined to get in the habit of having a little go-bag that comes indoors with me, keep it by the keys and carry it to the car each time. Slight hassle but I do the same (without bag) with gloves and a hat. This way your batteries and the light body are at least starting out with a little warmth even if that gets sucked away before too long. Would be smart for the primaries but also for li-ion.
I was thinking a buck driver would be necessary, too, but I’m not certain…probably depends on each particular driver and the chips used. For that matter, is there a low temp limit for any of these processors and such?
Streamlight Poly Tac - they have several configurations to choose from:
BTW to avoid problems with 2 CR123A cells in series don’t mix cells - always use 2 new cells from the same package and check their Voltage, don’t use Chinese made CR123’s and watch out for counterfeit cells.
I’m not totally sure about the driver. While the light specification doesn’t call out 2*CR123A, a reviewer had mentioned using them with no problems. And if it’s just for infrequent use, shouldn’t be a problem. I just wouldn’t run the light on turbo for many minutes.
There are some special ($$:money_mouth_face: 18650s made for cold weather. Also if you don’t require super high output, you could get an AA powered light and use lithium 1.7 volt L91 cells in it. That would also give you the option of alkaleaks if you have to.
I’m planning to make a go-bag too at some point, but in my opinion a car emergency kit should stay in the car. It wouldn’t do me much good if I forgot it at home!
