21700 is the future

I ave been a 18650 fan for a really long time… I have recently started carrying lights that use AA or 14500’s for size alone. The Lumintop Tool AA 2.0 have found the way in to the pocket. I have had to adjust my pockets since getting moved in to a manager position requiring professional office attire. Smaller knive, light, pocket tool, ect. The only thing that I have not swapped out for a smaller version is my phone.

While I like the idea of the 21700 not sure if I will ever be a convert.

I like the 21700 in my Wuben TO50R, but that is not an ADC light to me. My prefered EDC size is about the size of the discontinued Olight S15 and S15R, using AA or 14500 cells or up to the size and weight of the FW3A. The MH20 Nitecore is doable. A 21700 will never be my EDC. It is good to have choices to match our personal preferences, though.

40 Quatloos that the 18650 is revisited with improved chemistry, due to widespread use and compatibility with existing device & component designs.

I’m definitely interested in 21700 lights for certain things. But I’m 95% certain I’ll never EDC one due to size. I won’t EDC 26650 either. The 30T sure looks fun for hot-rodding.

Own a Zebralight, great light but the tint is like as Howard Stern would say……………….
Butterface

Still puts out really great though…………:slight_smile:

21700 cells are just a form factor.

Cylindrical cells can supports all kinds of builds and chemistries, so 21700s could be using a solid state electrolyte.

What I am kind of waiting/hoping for is a Zebralight "SC70d", basically an as-small-as-can-be 21700 flashlight (scaled up SC64 model for 21700 cell use). With a 90+ CRI LED, of course :)

General Motors just announced partnering with LG for new plant. Wonder what size they will use.

Pouches

An interesting 2018 technical article in the Journal of the Electrochemical Society, comparing 21700 to 18650:

http://jes.ecsdl.org/content/165/14/A3284.full

Some excerpts:

I have two 21700 lights. A C8F and a FF E07. The C8F isn’t pocketable at all to me, heads too big. The E07 I can pull off occasionally depending on what britches I am wearing. Colder weather and it’s Levi’s 501’s. The E07 isn’t fitting in that pocket without it being quite unpleasant to carry. I am most often working or running around after dark. I appreciate the run time of a 18650. Even then it has to be a fairly small 18650. Zebralight or DQG mostly. Most tube lights are too long for my liking.

I carry 18350 lights a lot as well. Armytek, Jetbeam, Reylight or a shorty S2+. Don’t carry AA\14500 much. SC52w or Reylight if I do.

Weight isn’t really a issue for me. I am a decent sized fella. 6’1” and 230lbs. I always carry a full sized, steel framed pistol concealed inside the waist band in a quality holster. If I can make that disappear and not notice the weight of it much, I highly doubt I will complain about flashlight weight. What I don’t like is things hanging around in holsters, on belt loops, or otherwise outside of my pockets or waistband. Too many things to snag me up on my day to day activities.

Is 21700 the future? For some things I’m sure they are. For flashlights? Not so much. I mean it’s not really the future, they are already here. It’s just an option available if you need it. Some do, some don’t. When 18650’s came out I’m sure someone tried to make the same observation. Yet we still have 10180, 14500, 16340, 18350 etc…… Sorry if I missed your favorite in between or oddball size. Point is they all still exist and are still made today even though at one time, 18650 was the future. They are even making better quality, higher capacity and higher current versions of those cells than they have ever made in the past.

So even the old cells still have a future. We are just at the end of a very long line of users for these cells. If battery manufactures had to depend on the flashlight folks to make their livings, they would die of hunger before the end of the first quarter.

I don't give a suck.

Save me from the wee turtles!

if 18650 battery suddenly will stop production then i can see the 21700 taking over, otherwise maybe not idk ??

To recharge the 21700 I use my old chargers, Trustfire TR-005 and TR-006, they take 73mm long batteries. I’m waiting for other more modern chargers but for now I use these

I don’t feel much difference between my SC700D vs D4 size wise, but with the zebralight it just seems like the battery lasts much longer.

This discussion has no point. 21700 cells are a new format which someone came up with just because it was of benefit to his industry, period. 21700 cells are already here, they're not “the future”. Indiscriminately favouring some stuff over another is stupid. There are many applications for which 18650 cells are still better suited than 21700s, so long live 'em and any other different format.

Let me say, for example, that some of you probably think or even believe the 26650 format trails behind in technology. I sort of agree and it has its reasons, but let me say they're not going to dissapear anytime soon, not by a long shot. Power Long Battery is probably the main standard bearer of the category, I see they're very focused in LiFePO4 (best LiFePO4 26650 cells in the market right now). And regarding their li-ion NMC cells, they're widely used in buses, logistics trucks and etc. within the Chinese market. And when you think how BIG is their bus fleet, you can understand.

Both 55A and 50A cells are listed here but not there. I think someone said they were discontinuing the 55A, hope not. Or at least hope they develop 60x, 65x or better models.

18650 is going nowhere within the next decade because of power tools. 21700 is not viable in cordless tools.
Also wouldn’t surprise me if some EVs continue to use 18650 even if tesla does not.

Has any EV manufacturer besides Tesla ever used 18650? None of the major brands available in the US have, AFAIK.

Not true. 21700 cells are currently being used in power tool battery packs, and outdoor power equipment battery packs.