18650 battery size specs.

[CAMVDCS]

I purchased a Nitecore P12 last week along with a Nitecore 18650 2300mah battery. I figured I should buy a battery from the same manufacturer as the flashlight. When it arrived, I put the battery in the P12 but it didn't work. I took the battery out and put it in my Olight M20S and it worked fine. I noticed that the P12 has a recessed area on the + side that the button top of the battery fits in. I also noticed that I the Nitecore button was slightly not level. I had an AW 18650 in the Olight so I tried it on my P12 and it works perfectly.

This week, I also bought an Eagletac G25C2 MKII XM-L2 and 2 Eagletac 18650 3100mah batteries. When it arrived, I put the Eagletac 18650 battery in the G25C2 and I couldn't twist the head. It was like there was locktite on it. I ended up twisting the head off and realized that the piece i twisted off exposed the LED emitter. Hmmm... that didn't look like the same head that was twisted off in a youtube video so I put it back on. I'm ready to send it back then I decided to try to wrap the knurl with a t-shirt and use a pair of large pliers to see if I can get the head loosen up. I was finally able to loosen up the head so that I can twist it to change modes. But it was still pretty tight in the turbo & high mode. I tried twisting it back and forth to see if it would loosen up but it was still relatively tight. I thought maybe I should order some Nyogel to apply on the threads. Then I thought let me swap the Eagletac battery with the AW. Once I put the AW 18650 in the Eagletac, twisting the head was smooth as silk. I think the Eagletac battery was a bit too long and it put excessive pressure on the head and that is why it was so tight to twist. I now have the Eagletac 18650 in the Nitecore P12, the AW 18650 in the Eagletac G25C2, and the Nitecore 18650 in the Olight M20S.

It looks like the there are some variations with the size and quality of various 18650s. Am I correct to assume that there are varying tolerances among different manufactures of the 18650s? It does look like the AW 18650 seems to work in all of my flashlights. Is the AW a good brand? I think I bought this AW 18650 about 3 or 4 years ago.

After this experience, it makes me leary to buy a flashlight with a twisty head and I'm thinking that the 18650 battery has to fit perfectly on these Nitecores.

 

[18650]

It's trial and error.

There is no standard for a lot of these characteristics and I'm not talking about cell length. Things like the diameter and height of the button (if any), thickness of the wrapper, or what current/voltage trips the protection circuit are left up to the manufacturer to decide and this is on top of the normal manufacturing variations (tolerances as you called it).

edit: Wanted to add the recessed area on the positive side is a physical mechanism to protect against the bad things that can happen in case of reversed installation of cells. A lot of lights use this as a form of reverse polarity protection and you have to use cells with buttons on them and even then not all will work due to varying sizes.

 

[MR.355]

Have a look at: http://lygte-info.dk/review/batteries2012/Common18650Summary%20UK.html

Lots on info on various batt's

 

[ven]

I use unprotected cells in some single cell lights as well as protected.Unprotected keep the length down from 2-4mm dependent on brand so are actually 65mm long.

As long as care is taken(which should be regardless if has pcb or not) then maybe an option to try.

I use samsung/sanyo/pany(green) unprotected cells ,just top them off after X amount of use,if light has built in V reading or has protection then no need imo for protected cells.More use as an extra safety buffer for people new to the cells imo,or if used in multi cell lights.

Peeps have different opinions,common sense,good unprotected cells and charger.Job done,may suit the light better regarding issues.......only a thought

I have various sizes of protected cells,sure my pany 3400 protected are up there as the longest i have along with the sanyo protected.

 

[CAMVDCS]

Thanks for the link MR.355! Thanks very interesting info on the 18650.

 

[CAMVDCS]

It's trial and error.

There is no standard for a lot of these characteristics and I'm not talking about cell length. Things like the diameter and height of the button (if any), thickness of the wrapper, or what current/voltage trips the protection circuit are left up to the manufacturer to decide and this is on top of the normal manufacturing variations (tolerances as you called it).

Yeah, I'm learning. Luckily I've been buying different brands of 18650 and not sticking to one brand although I thought I read something on the forum that the AW was a good quality battery. I have AW, Nitecore, Eagletac, & Tenergy so far.


edit: Wanted to add the recessed area on the positive side is a physical mechanism to protect against the bad things that can happen in case of reversed installation of cells. A lot of lights use this as a form of reverse polarity protection and you have to use cells with buttons on them and even then not all will work due to varying sizes.

 

[RI Chevy]

I use unprotected cells in some single cell lights as well as protected.Unprotected keep the length down from 2-4mm dependent on brand so are actually 65mm long.

As long as care is taken(which should be regardless if has pcb or not) then maybe an option to try.

I use samsung/sanyo/pany(green) unprotected cells ,just top them off after X amount of use,if light has built in V reading or has protection then no need imo for protected cells.More use as an extra safety buffer for people new to the cells imo,or if used in multi cell lights.

Peeps have different opinions,common sense,good unprotected cells and charger.Job done,may suit the light better regarding issues.......only a thought

I have various sizes of protected cells,sure my pany 3400 protected are up there as the longest i have along with the sanyo protected.

X2

 

[Qooo]

Have a look at: http://lygte-info.dk/review/batteries2012/Common18650Summary%20UK.html

Lots on info on various batt's

:goodjob: Thanks for the linky.

 

[kingwellenergy]

Manufacturers produce the lithium ion 18650 at a size of 18 mm by 65 mm. Consumers may find a "D" at the end of every 18650, which denotes the shape of the battery. Newer 18650s possess a protection circuit that adds additional length to the battery. Labels and packaging also alter the size of 18650s, adding further confusion to the way consumers can use the battery.