Batteries: 18650 vs...

[Vaultman]

I've read a few threads on here about going to 18650 for headlamps. I am kind of a wannabe flashlight nerd. Since getting an EDC flashlight (starting with 18650's) I have had a few different ones the last 5 years or so. I have kind of become a nitecore fan. (Currently have E4K, MH25, MH10S, and another one, I cannot remember because it lives in SWMBO's car).

I am considering getting rid of my 18650's (and lights that use them) and sticking with the larger 21700 size batteries. Only negative I see to this is losing the option of the 18650 headlamp (which I do not currently use anyway). Is there anything else I am giving up by not using 18650's and using only 21700?

Shipping a used 18650 battery... Does this cost extra, or do you just have to declare it?

 

[NRA4LIFE]

Not sure if you get charged anything, but I have been asked every time in the last many years checking in if I had any lI batteries in any of my bags.

 

[Novashooter]

If going to a single size is the goal, I wouldn't be going bigger. An 18650 is already pretty big. I'd rather go to a 14500, although I'm not sure what devices are out there that run these.

 

[Vaultman]

I just pulled my 18650 out and compared it to the 21700. There is a bigger size difference than I recall. Seems like I may want to get another EDC that uses 18650 just to reduce the overall carry size... Gotta get another light!

 

[Vaultman]

Just got a nitecore NU 25 UL Headlamp. First impressions are really good. I am pretty sure it will be my go-to this season and EDC this winter.

 

[BRTreedogs]

I think if you ship a battery. Declare it and it has to go ground.
Batteries in the un pressured part of the aircraft is the real life of what the movie cast away was based on.
They started on fire.

 

[Marbles]

Li batteries must be shipped ground, unless installed in equipment (why cell phones and such can be overnighted).

Power to weigh ratio goes up as you move to bigger batteries. I have no reason to go bigger than 18650 though.

I like Zebralight and Malkoff Devices.