Inline Fuses

[Sci]

Wow look a $0.55 part that can add protection !! Nobody bothered to do it yet but ?

I've got some ordered, can't do anything until they get here. Hopefully something like this & the use of protected batteries will keep anyone else from getting hurt. Who knows, maybe the current PCBs in protected batteries can be modified to include a protection circuit triggered by excessive current, not just shutting down due to high/low voltages as they are now. We'll see.

 

[BuzzKill]

That circuit is already in the battery , overvoltage needs to be looked at also , I am not sure ? but there may be a big spike in voltage before a blowup ?? there for sure is a spike in current at least before they go ballistic. Current limiting is Definitely needed !!! Before it gets to the battery.

 

[Sci]

That circuit is already in the battery

How does the protection circuit in a protected battery actually work? I know it shuts it 'off' if voltage drops below a certain level. Does it also keep the battery from overcharging or is the charger responsible for that? Does anyone have a link to a thread where the battery that malfunctioned was a protected one? The only threads I have been able to find were using unprotected CR2s or CR123s.

 

[MrPuff]

This thread seems to have died. I really think there are good ideas here. Just got some my polyfuses in today and figure I would post a pic to show two different styles. Yes the tiny little green spec is a polyfuse lol. TINY!

 

[Guineahill]

It is tiny! Looks like a cupcake sprinkle!

 

[gratefulme]

I can't solder the regular connections on a nicostick. Can you imagine trying to solder those connections. 8-o My emotions as I try to solder it lol.

 

[MrPuff]

I can't solder the regular connections on a nicostick. Can you imagine trying to solder those connections. 8-o My emotions as I try to solder it lol.

LOL yes they are a challange, I think to do it would require pushing around a small bead of solder although reflow soldering would probebly be the best bet for the little guys. I figured I would play with a few because if not to difficult to manage they take up NO space in a design. The bigger ones are more user friendly by far.

 

[Kirothak]

wow thats stupid small, if something that small could add a good layer of safety then hell yahh! other then trying to work with something that small, thats beyond my skills i am sure. but i hope to see marketed PVs with such devices.

 

[petercro]

Mr P.
I'm away at the moment but got mine the day I left,
Do you intend to run any tests on them, and if so how.
The trip current on mine is 2.2 Amps.
My attys draw 0.96 Amps. So I was thinking of trying to run 3 attys of one battery to get the current high enough to trip the polyfuse.

For peace of mind. I would like to SEE it work.

 

[Rocketman]

I'm not sure which polyfuse I would use.
I guess it would depend on the atty/carto I was going to stick with, or have a mod set up just for each type, which is not really a problem, as long as it doesn't go over 20 to 25 or so.

A polyfuse seems to be a ice little device, and can save the day with power buses in expensive computers using Li-ion batteries. So using them in e-cigs seems a no brainer.
Just not sure which one I would use.
The hold current seems to vary with temperature (internal temperature next to the fuse)
and trip times and current indicate this isn't a fast blow device.

An example I found that would probably work with a high resistance atty like a 901, running on 3.7 volts is one with a rated holding current of 2 amps @ 20 degrees C. Since the internal temperature of my MOD is probably a little warmer than the outside, and the outside feels a little warmer than me, then the inside might be about 60 degrees C. THis polyfuse has a rated holding current of 1.3 amps at 60 C so that would still probably work with the 901 @ 3.7 volts. But the 0.1 second short circuit trip current is rated at 16 amps. I'm not sure that would be good enough. Just not sure.

The 3.5 amp @ 20C one would probably work with my 510 mod and I would have to go any bigger because I don't do high voltage vaping.

Any suggestions on which one would be the best for the 901 and which one for the 510, and could I use the one for the 901 with and 808? These things seem to have a really large temperature coefficient.

Rocket

 

[MrPuff]

Mr P.
I'm away at the moment but got mine the day I left,
Do you intend to run any tests on them, and if so how.
The trip current on mine is 2.2 Amps.
My attys draw 0.96 Amps. So I was thinking of trying to run 3 attys of one battery to get the current high enough to trip the polyfuse.

For peace of mind. I would like to SEE it work.

Well haven't figured out how I was going to test them honestly lol, I am so busy mod building its not even funny lol. First thing I am going to do is mod a tester and put a large polyfuse on the ground wire between the rest of the circuit and the battery and make sure it vapes fine. As far as testing their function, only thing I thought of so far is using multiple batteries in series to pass its limits and see how it reacts. Was just going to use a led to show if current is broken or not.

The tiny ones I have trip at 2a, the larger ones I believe trip at 4a.