stacking batteries question? Dangerous? Or minimal risk?

[siouxsie]

Another vendor has told me a story where he says he can't recommend stacking batts anymore as someone's mod exploded injuring them in the face rather badly. Using 2 LiFePO4s. Which I use. Every day lately...lol.

Now aren't these protected or "safe" chemistry batts often designed to be used in series, and what exactly is the risk, if any? Thanks and I'm asking anybody with expertise or from MV to chime in.

Cheers everybody and have a great week! ~Scott

 

[5vz]

Here is roly's posts on it, I'll be back with the battery info.

http://www.e-cigarette-forum.com/fo...s/76078-exploding-mods-current-situation.html

 

[5vz]

Battery info, be sure to read all of his posts:

http://www.e-cigarette-forum.com/fo...9007-warning-rechargeable-batteries-mods.html

 

[Sjkader]

I guess the next question would be, What are the rating of these RCR123a LiFePO4 Rechargeable Battery

 

[siouxsie]

Thanks, that helps...lots of info...looks like my Tenergy LiFePO4s are going in the recycling and some more AW LiFePO4s are in order. Also sounds like some vendors could do a better job with the batts they sell and the mods they make.

 

[siouxsie]

I guess the next question would be, What are the rating of these RCR123a LiFePO4 Rechargeable Battery

Likely not 4C or higher at the price...

 

[Sjkader]

Likely not 4C or higher at the price...

Thats not what i want to hear. I have 7 sets of these. lol

 

[siouxsie]

Thats not what i want to hear. I have 7 sets of these. lol

Tell me about it, they're cheaper or near same price as Tenergy, which I have several sets of, and are going into retirement. Still, I think much of the issue is mod build and user error, as well as condition of the batts which should be inspected. I just wish AW made more batts and they were more readily available. You can get AW LiFePO4s. Maybe just fire them a couple times at a distance first just in case.

 

[Sjkader]

I have been using the same sets for a long time. They are never dropped. I check them over constantly. I hate to get rid of all these as they have been little work horses for me.

 

[siouxsie]

I have been using the same sets for a long time. They are never dropped. I check them over constantly. I hate to get rid of all these as they have been little work horses for me.

Me too, but neither do I want burns on my face and an atomizer embedded in my face because I'm using 1C batteries stacked to get 6 volts. Ever notice that they can get pretty warm during a heavy session? If not, maybe your batts are ok. And you are right on the money with your precautions. When higher quality batteries (Lifepos) are available, with higher output rating, I think that's the directions I'll be going in the future (AW). Especially when a maker of very high end non regulated mods with all required safety features tells me he can no longer recommend stacking any batteries period.

I think that's an over reaction, but this issue is a hot button one right now, obviously. And if you read through all that info, even with all precautions, ECF straight up says not to use any batteries less than 4C rated (cheap Lifepos). I believe the maker of the batts you have is Haobra...maybe there is info on the web. Haoba rcr123a 3 volt Battery Kit And maybe Madvapes will provide the output max amperage rating.

 

[Sjkader]

I did submit a ticket asking for the info. Just for peace of mind. I guess I really have not noticed them heat up. I think I would notice since i never put my pv down. Pretty much sleep with it at night. (right between me and my better half) maybe MV will get me the info i requested. Im not worried to much about me as i am the good looking one of us. She would kill me if one went off in her hand, let alone one of her coach purses. LOL

 

[Kevin littell]

look at it this way....


1 3.7 volt battery running thru a 1.5 ohm cart = 2.46 amps of current drawn from the battery.

Now, stack 2 3.7's batteries and its 7.4 volts.....running thru that same cart and its 7.4/1.5 and its 4.93 amps.


Now, if you've checked your batteries and they will handle the addition draw, and your switch os rated and 5 amps and the connecter to your cart is clean and resistance free you shouldnt have a problem!

If not its the equivilant of Russian Roullette. Spin the chamber, aim it at your mouth and hit the fire button.



For referance: Ohms law states E (voltage in volts) = I (Current in Amps) x R (resistance in ohms)

__E__

I x R (I hope this prints correctly.)


Know the ratings of the equipment and batteries before you stack or change anything and if your gonna double the volts think about going standard resistance on the carts....
Oh, one more point....If all of these numbers seem confusing or pointless......Go with the batteries your PV came with and never stray from the beaten path.The face you save may be your own.




IMHO YMMV HANL TTFN

 

[dale1962]

Sjkader let me know what u find out I use the haoba batts stacked all the time at 6v too........I go to MV shop all the time well I used to haven't been there in over a month due to job change,but anyway I know Mark from dealing with them for awhile now and he is pretty damn smart and knowledgeable about electronics and don't think he would sale anything unsafe.Also Op mentioned about the price of them being so cheap and assuming they are less than 4c rating well wiil see but I don't think so.Sure Mark(Hoog) will chime in here and let us know for sure.But if u think about it almost everything MV sells is a lower price than anywhere else so probably just giving us a good deal on the haoba's.

 

[siouxsie]

Yes, do let us know if they are rated at least 4C. It was premature of me to assume they're not and I would be more than happy to know that they are rated high enough. More sources for safe batteries is a GOOD thing. And certainly let us know if they are less, such as the tenergy @ 1C. I could not find any discharge info on the web for the Haoba batteries and they are sold by other ecig sources as well.

When I run my voltmeter on these stacked I usually get 6.7V when new and 5.6V when drained, so I can do the math using Ohms law on a single coil carto rating but how does it work if I'm using a DC or TC at 1.5 ohms? Does that double or triple the max discharge rate that I need out of the battery? Question for Kevin, I think.

 

[Sjkader]

I will sure let everyone know when i get a response. Maybe Hoogie will pop in and answer before then. All I use are two stacked for 6v vaping. Always have. Always will.

 

[Kevin littell]

whats the switch in your PV rated for? Will it take 5 amps? What is the connector rated for??? Will it take 5 amps?


I'm gonna leave this very open intentionally. Anywhere between the battries and the coils that is not rated for the required curret will either burn open (you hope )or vaporize in a flash of molten metal and plastic.


You really gotta know alot more about your PV.


Single coil or dual coil, they should be labled for average resistance. Use that rating in the formula.

 

[siouxsie]

okay that answers my question then, whether dual or single coil, the rated and detected resistance of the carto/atty is the number used in the equation. Can't wrap my head around it really, since for a dual coil, let's say 2 ohms, has 2 4 ohm coils in parallel. At least as I understand it.

My Darwin confirms it though...a 3ohm DC, run at 11.3 watts, registers 6V and 1.9amps...

So if I had LiFePO4s rated at least 4C, I could use them stacked in an 18650 mod. So my AWs should work, but at <550mah, my Tenergys will stay on the shelf.

Nobody is using 1.5ohm single coils or Dual coils at 7.4V, I would think. I don't even think I'll need that for my 3ohm DCs. Thanks a bunch for the info, Kevin.

 

[mnementh666]

Now, stack 2 3.7's batteries and its 7.4 volts.....running thru that same cart and its 7.4/1.5 and its 4.93 amps.

...its the equivilant of Russian Roullette. Spin the chamber, aim it at your mouth and hit the fire button.
...
Anywhere between the battries and the coils that is not rated for the required curret will either burn open (you hope )or vaporize in a flash of molten metal and plastic.

While I agree with what you are saying, I think you are taking things perhaps a bit far. Note that a 1.5ohm cart/carto on 7.4v would be 36 watts. I don't know about you but that seems a tad outside the range of usability. Not to mention the longetivity of *any* carto or cart at that range. And that's only touching on _nominal_ voltage. Note that 3.7v batts routinely run in excess of 4.1v charged, thus increasing said ratings further still.
And realistically, as far as the wiring/connector/switch, or even the PCB on some PV's... We're talking less then 10 volts, direct current. Please correct me if I'm wrong, but the likelihood of a switch or wiring "vaporizing in a flash of molten metal" is probably only slightly better than having a truck drive through my bedroom at night.
Batteries exploding... Yes. Absolutely. Lithium is a reactive, potentially flammable metal.
I will not purchase a non-vented PV if it's made of metal (which you'll note is part of the posting linked earlier). And even prior to reading about this very unfortunate case, I won't stack batteries. Just too many variables and consequences.
We should all be very very aware of what goes on within the equipment we use. But blowing all this out of proportion is perhaps counterproductive.
Thanks for listening.

Edit: gah. Forum won't recognize spacing for paragraphs. Sorry. I blame tapatalk ;-)

Sent from my HTC Vision

 

[Kevin littell]

Take a look at the wiring of a Visions Clearomiser....


The coil on the top is wired thru some hair thin wire running the lenght of the tube.



I personally dont want to run much more then an amp thru it....5 is gonna melt it.


But alot of box mods are point to point wired, alot of tube mods use thin wire instead of direct connections to the battery or have PCB's between the battery and the switch and MANY of these devices are built by the lowest bidder overseas. I've made a DAMNable good living off of electronic "thingys" melting and burning up thru the years and I dont see anything different about these E-cigs except that noone really gives a daymm about how they work, they just want more vapor. "Stack batteries, GO LOW RES......More POWER!!!Variable VOLTS!!!"


I'm waiting for a 12VDC device to come out....It'll sell Thousands!!!

I use an Ego-T 18650....regulated at 3.x volt by a pcb between the battery and the switch. Ok for low res or standard but doesnt vape well at 3 ohms or better. I use standard res atties cause they vape ok for me and dont exceed what I think is the current rating for the cheap wiring I see in these cheap atties.(theres a PCB between the battery and the switch, what current is it rated at???I dont know.) The batteries are charged inside a metal box and rotated regualrly....I meter them weekly.....Ok, maybe I'm strange.......


Now, if I have a purely mechanical hand made device with direct connects and a mechanical switch I'll stack and buy good protected batteries, use reliable rebuildable atties and vape away!



But if its massed production?


Anyways, its all a personal decision. I've been in electronics repair for the last 31 years.....What would I know worth sharing???


(Us old foggies tend to blow thing way out of porportion anyway so just ignore me.)

 

[siouxsie]

never mind...just realized they gave me the Tenergy specs and not what I asked for.