21700 is the future

Do vaping and flashlights make a significant impact on these battery innovations? I’m just wondering out loud.

I do not vape but I bought my batteries online from vape items vendors. All my 18650 Enooks were advertised first for vaping, except for the XTAR with PCB which was advertised for flashlights. I’ve considered “recommended-21700 battery” flashlights. But 21700s are much more expensive than 26650s. So I ended up with five 26650s and zero 21700 for my Sofirn SP33V3. Local market prices played a big role in my choice.

As long as there is a profitable market for these different battery sizes they will remain.

All (decent) “vaping” or “flashlight” batteries are rewrapped LG or Samsung or Panasonic cells which are exclusively made for electric cars and other electronic appliances.
I can assure you that nobody working at the R&D facilities even thinks about their applications in vaping or flashlights.

Molicel marketing department actually looks to care . On the other hand in most other companies the legal department is the only one that cares about vaping. Flashlights just don’t register (probably for the better).

From page 3, of this thread…

This is what LG thinks about vaping and flashlights.

That actually is a battery wrapper condition use safety video.

I EDC the Olight Seeker 2 Pro, (with a clip) and I do not even feel it in my pocket. I wear 5.11 and other pants like them, so it is easy to carry stuff. Glock, knife, light, phone, wallet, keys, etc.

18650 vs 21700
Ultimate question, I’m trying to find answer for, last couple days.
I’m buying my first true flashlight, cannot decide between S2+ and S21A with SST-40.
I don’t care about max brightness - 5A/6A, flashlight is going to become hot in couple minutes anyway.
I’ve compared expected battery life with different settings and drivers, with currently top of the line batteries - 18650 (3500mAh), 21700 (5000mAh).
Which one would you go for, for allround flashlight?
Do you think, the additional weight (body + battery) and dimensions are worth the extra 19% runtime (on 10% and 35% modes it is 7hrs vs 8,3hrs and 2 vs 2,38hrs).
I want to use it as allround light - around the chalet, camping, throw in backpack when hiking, around the house, fishing etc…
My table comparing expected runtimes:

Which one would you pick? So is the 21700 new standard, and am I going with standard which is going to disappear?

No way I can carry a 21700 size light. I was carrying a 18650, but now I can’t do that - I have to lighten my load to AA (with jacket) or AAA (without jacket).

What you can carry while backpacking depends upon your style. If you are always in a hurry to cover as many miles as humanly possible and spend the big bucks on titanium everything, go light. If you slow down to enjoy the blossoms and keep the mileage down, you can carry both a 21700 and an 18650 plus spare batteries. I carry a 26650 thrower because it is really fun to spot animals at night. I might as well just do day hikes if I cannot enjoy it out there at night.
As far as the future, maybe neither will be around when my supply of batteries diminishes. Still, they cost much less than my boots and backpack so no big deal there. But most hikers go light weight nowadays and would not wear the heavy leather boots of 40 years ago (including me), but it worked back then. So try something like a headlamp and change it if it does not suite you. Have fun out there!

Good question. I’m getting a couple of 21700 hosts and will find out soon. I’m liking the 5000 mAh vs 3500 capacity for not that much more volume, but maybe that’s going to be too big for an EDC.

I find my Convoy M2 to be too big for an EDC, but it’s still 18650. My S2+, S2, S3 are so much more easier to put in my pocket. The hosts I’m getting are 126mm x 27mm vs 124mm x 24mm for an S2. That doesn’t seem that much bigger to me.

does anybody know the continuous discharge rate of sofirn 21700 4000mah batteries?

I have so many 18650 cells. It’s nice and small. 18650 is for EDC, anything thicker is for packing in a car, backpack, etc

Absolutely not. Its much bigger and heavier for a difference barely noticeable if you EDC it.

Your math is off slightly. You gave the 21700 20% extra current over the 18650, 5amps vs 6 amps. Then you still get 19% more runtime.

I use a 21700 duty light because I know I can use it all night if need be. Right next to it is a 18650 tactical light. I’m also exploring a 26800 light build for more rural areas. The real issue is 4.2 volts is the standard. For this allows the variety of battery size too be so easily used. Variety is the spice of life. You guys would love the gun forums with; 9mm vs .357 Sig vs .40 cal vs 10mm vs .45

depends what battery they are using… maybe 30A if highdrain ?

well ya thats my question, i dont know which batteries they re-wrapped

I have some very small / pocketable 21700 lights. The Imalent MS03 for example or the Lumintop FW21. And of course the Acebeam W10 Gen 2

Totally worth the small increase in size for 14,000 lumens for the Imalent and 1,200 meter beam for the Acebeam compared with an 18650 light

I would consider EDCing a 21700 but not if it’s over 100mm long.
Last week I’ve been searching for such a light and the Lumintop FW21 would be good size wise.
It did look great until I found reviews. The runtime is simply (very) bad.
I always pick a light that runs a long time on about 300-500lm.
But 2h39 at 333lm isn’t good at all. Many 18650 lights do much better.
I’m not going to buy a bigger light with less runtime….

I’m waiting for a budget 4x21700 flashlight, 4000k, USB, with Anduril!