Lithium battery failure = boom (I'm okay)

[chad]

Originally Posted by Dave Rickey

I'd apologize for the caps, but I think too many people are disregarding safety in how they build their devices. These are not toys, the only electronic DIY I can think of with a higher danger factor is a hand-portable medical or industrial-grade laser. If they were running off of a thermite fuel cell, would you be so casual with them?

Wow! Thanks for the wealth of info in this post. So since you know quite a bit about this, tell me:

If I were to use an unprotected AA size Li-ion 3.7v 750mAh battery like the 14500 in a mod. Could I use a PCB such as this one for device level protection? Do you know anything about the nuances, like how long the leads can be or what their minimum resistance must be to ensure the PCB cut-off functions correctly?

I've got a mod in mind that needs a standard AA size but would have room for a PCB separate from the battery. Though the PCB probably wouldn't be switched out whenever the battery finally gives up so it needs longevity.

[nubee]

FYI -

VaprLife.com now sells 10440 (AAA) protected trustfire batts

[warp1900]

Originally Posted by nubee

FYI -

VaprLife.com now sells 10440 (AAA) protected trustfire batts

Yeah, they also sell what they call adapters that look like my dog chewed on them before putting them up for sale.

They claim a lot of things that are not true, so why think that one is?

Anyway, people still buy from them, so that should say something about consumers.

Sorry if you are the owner or a friend of the owner, just sayin...




-

[Dave Rickey]

Originally Posted by chad

Wow! Thanks for the wealth of info in this post. So since you know quite a bit about this, tell me:

If I were to use an unprotected AA size Li-ion 3.7v 750mAh battery like the 14500 in a mod. Could I use a PCB such as this one for device level protection? Do you know anything about the nuances, like how long the leads can be or what their minimum resistance must be to ensure the PCB cut-off functions correctly?

I've got a mod in mind that needs a standard AA size but would have room for a PCB separate from the battery. Though the PCB probably wouldn't be switched out whenever the battery finally gives up so it needs longevity.

The one you point to wouldn't be a good option, if you zoom in, notice that it was hand-soldered (and a +/- 1A/33% error margin?), although I was thinking more of the ones that people tear out of protected cells. The stick PCB's from the same store would be a better choice (won't let me link it because I'm a newbie here).

--Dave

[Dave Rickey]

After a little research, I am pretty certain that lead length over any reasonable distance for an eCig (inches) isn't going to matter unless you are using something too fine for the amperage (so under 30AWG for a single-cell design). Lead resistance could be a factor for runs of more than a few inches, or if you're pushing too much current, or if you're using a very small cell (a 14500 shouldn't be affected significantly, but if you drop down to something ridiculous like a 10180, it's going to be a big issue, and probably is for standard eCigs).

But frankly: Why use an unprotected 14500, when the length difference is trivial (or non-existent if you get a cell that has a shortened can to compensate)? I'm looking at unprotected cells because my space limits prohibit any protected cell other than the 16340, and the 18350 has more than 50% higher real capacity, which crosses a critical threshold in terms of vaping capacity (a day plus comfortable margin, vs. *having* to carry spares). Hell, can you even *find* an unprotected 14500 for sale?

--Dave

[SolidSnake]

Originally Posted by LuckySevens4U

Thanks Wiz, many want to minimize my thoughts and even mock me on this forum, which is extremely immature and obvious, but my vote goes towards safety first for everyone!

Better safe than screwed, I always say....

...or, "better safe than scorched", in this case

[PaulZ]

cell phones have exploded a bunch of times. its a % allowed failure rate that companies are allowed on batteries/etc.

i don't see it being a "bannable" problem

[Sprocket]

Does anyone know if the janty stick has a protection circuit? After reading this im a little nervous about using it :-S

[chad]

Originally Posted by Sprocket

Does anyone know if the janty stick has a protection circuit? After reading this im a little nervous about using it :-S

Don't sweat it. The JSv2 has a device-level protection circuit. That is, protection is built into the Janty Stick.

[Sprocket]

Originally Posted by chad

Don't sweat it. The JSv2 has a device-level protection circuit. That is, protection is built into the Janty Stick.

Thats good to know Since reading this thread ive been vaping sideways with the battery lid facing away from my face LOL