Question about Parallel batteries

So, today I walked in the vape shop, holding my mech pro mod, with a 0.08 ohm resistance...
Everything was going great and then a tell the guy there about my coils and he freaks the fuck out...
He told me to get that thing away from him, and that if I value my fingers I should putt an atleast 0.3ohm in there... I told him that with two VTC5a's in there in parallel I pull a pretty safe 45 amps...
Then, he told me that in parallel the current stays the same and the only the capacity doubles...
And right after that he just casually says that batteries in series double voltage and amperage...
I was like WTF is he on about...

I was dead ass banned from the shop because in his own worlds "what I'm doing is suicidal and he doesnt want to die with me"

Im still in a state of "what the actual fuck"

Is that guy right about anything?

45 amps on 2 batteries us unsafe. Since most batteries barely test beyond 20 amps NEW... AMP rating reduces with every push of the fire button and charge cycle. So yeah you might theoretically be mathematically safe...

Just remember Reality is a BITCH.

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HondaDavidson said:

45 amps on 2 batteries us unsafe. Since most batteries barely test beyond 20 amps NEW... AMP rating reduces with every push of the fire button and charge cycle. So yeah you might theoretically be mathematically safe...

Just remember Reality is a BITCH.

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Ok, soo just to be super clear, I was right about the current being dubbled in a parallel config?

Yes, you have double the amperage with parallel at the voltage of a single cell,
Series you have the amperage of one battery and double the voltage.

At a rating of 25 each for a VTC5A you are right at or below the CDR, especially after factoring voltage sag. If anyone is going to blow themselves up it’s him, thinking he has double the amps on a series mod.

First off, the amps that are being drawn stay the same, but are divided over two batteries instead of only one, thus halving the amps that are being drawn per battery. (If you look at series from this exact same perspective, you will see he was actually correct on both counts.)

That said, you can't just double the amp rating of your chosen battery. That's because the weakest battery of the two (the one that has the highest internal resistance) will receive the highest amp load as well as because the individual battery contacts (and the wiring, if applicable) of the parallel mech mod have different resistances so you need to account for that, and you also need to add another safety margin to that. If you know what you're doing and if you already know that this imbalance isn't too far off, then (as an experienced mech user) you could decide to pick a 15% margin for the safety. A margin of 50% should generally be recommended only to vapers who are still new to this kind of stuff, just like staying at or below the CDR should generally also be recommended only to vapers who are new to the mech. Exclamations like "Put an at least 0.3 ohms in there" should be considered proof that the shop owner is essentially just clueless and a moron, despite that it can be argued the fact his explanations about parallel and series were correct after you also factor in a different type of semantics. Bottom line, he is a clear example of what I call an ohms nazi. Could just be his way of telling you to piss off for whatever the real reason he might have had that I don't know.

GeorgeTz6 said:

So, today I walked in the vape shop, holding my mech pro mod, with a 0.08 ohm resistance...
Everything was going great and then a tell the guy there about my coils and he freaks the fuck out...
He told me to get that thing away from him, and that if I value my fingers I should putt an atleast 0.3ohm in there... I told him that with two VTC5a's in there in parallel I pull a pretty safe 45 amps...
Then, he told me that in parallel the current stays the same and the only the capacity doubles...
And right after that he just casually says that batteries in series double voltage and amperage...
I was like WTF is he on about...

I was dead ass banned from the shop because in his own worlds "what I'm doing is suicidal and he doesnt want to die with me"

Im still in a state of "what the actual fuck"

Is that guy right about anything?

Click to expand...

Don't think he got anything right.
Parallel doubles the current but keeps the voltage the same.
Series doubles the voltage but keep the current equal to what on battery will handle.

On safety. As long as both batteries keep making good contact you should be ok on the current as the VTC5A is a 25 amp battery as I recall. so if everything works fine then 50 amps max.
However if one of the batteries has a contact issue or something you will be putting 45 amps on one 25 amp battery.

Not the way I would vape but....
I stay above .2.

This post makes me sad.

Go back to the shop and get him fired.

GeorgeTz6 said:

Ok, soo just to be super clear, I was right about the current being dubbled in a parallel config?

Click to expand...

In a theoretically perfect world amp draw limit doubles.... for parallel.

In reality... to be safe one adds in a margin of 15 to 20% to account for wear and tear.... internal resistance of all components..... and charge state.... and for shit happens factor.

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I probably should note, a 50% safety margin to account for the imbalance between the two batteries is calculated as follows:
Take the CDR of one battery (25 amps for the VTC5A) and then add 50% of that, so 25 + 50%×25 = 25 + 12.5 = 37.5 amps max instead of 50 amps max. For a 15% safety margin, this would be 25 + (100% - 15%)×25 = 25 + 85%×25 = 25 + 21.25 = 46.25 amps max.

GeorgeTz6 said:

So, today I walked in the vape shop, holding my mech pro mod, with a 0.08 ohm resistance...
Everything was going great and then a tell the guy there about my coils and he freaks the fuck out...
He told me to get that thing away from him, and that if I value my fingers I should putt an atleast 0.3ohm in there... I told him that with two VTC5a's in there in parallel I pull a pretty safe 45 amps...
Then, he told me that in parallel the current stays the same and the only the capacity doubles...
And right after that he just casually says that batteries in series double voltage and amperage...
I was like WTF is he on about...

I was dead ass banned from the shop because in his own worlds "what I'm doing is suicidal and he doesnt want to die with me"

Im still in a state of "what the actual fuck"

Is that guy right about anything?

Click to expand...

Imo anything less than 0.1ohm is unsafe on any 2x18650 battery pair..... for me.....

I know of people that regularly vape .08 on single batteries.

They haven't blown themselves up yet so I assume that like jumping out of a plane at 10000 feet.... deadly things can be done safely.

SAFE is relative and subjective.

Sent from my SCH-I605 using Tapatalk

There is nothing about vaping that is TOTALLY safe.

HondaDavidson said:

In a theoretically perfect world amp draw limit doubles.... for parallel.

In reality... to be safe one adds in a margin of 15 to 20% to account for wear and tear.... internal resistance of all components..... and charge state.... and for shit happens factor.

Sent from my SCH-I605 using Tapatalk

Click to expand...

Came here to say this, each cell will have minor differences, it's good practice to leave at least a minimum of 10% as room for error.

I use HB6's in parallel which are 30A per cell and will not go below 0.08

Mykreign said:

This post makes me sad.

Go back to the shop and get him fired.

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me too man. the people in these shops are supposed to be able to help noobs and teach people. theres so many idiots behind the counters at vape shops, im surprised there isnt more people getting hurt. one of the guys at one of my local shops has told me on different occasions: 'mech mods should be banned because NO ONE is smart enough to use them', 'i won a cloud comp running a a.08 on a tube', 'building coils is a waste of time when you can just buy premade 26/32 clapton wire' and my favorite 'NO ONE vapes over 3mg any more'...there was a time in my area where there were at least three shops with real experts in them. now we are down to one single guy, who knows what he is talking about, out of four dedicated vape shops. the people at the xxxx shop know more about vaping and they only sell juice and starter kits there.

GeorgeTz6 said:

So, today I walked in the vape shop, holding my mech pro mod, with a 0.08 ohm resistance...
Everything was going great and then a tell the guy there about my coils and he freaks the fuck out...
He told me to get that thing away from him, and that if I value my fingers I should putt an atleast 0.3ohm in there... I told him that with two VTC5a's in there in parallel I pull a pretty safe 45 amps...
Then, he told me that in parallel the current stays the same and the only the capacity doubles...
And right after that he just casually says that batteries in series double voltage and amperage...
I was like WTF is he on about...

I was dead ass banned from the shop because in his own worlds "what I'm doing is suicidal and he doesnt want to die with me"

Im still in a state of "what the actual fuck"

Is that guy right about anything?

Click to expand...

Sorryy to hear that.

TIL there are a buttload of idiots that work in vape shops and 'in general' idiots don't know that they are idiots. Often times they believe that they are fonts of knowledge.

mach1ne said:

heres so many idiots behind the counters at vape shops, im surprised there isnt more people getting hurt. one of the guys at one of my local shops has told me on different occasions

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You'd be surprised how many shops that don't see the point in vaping under 0.3 so they ignore everything under it and chastise anyone who vapes low, one shop that used to be in my area wouldn't sell coil heads under 0.5ohms even if it meant they would lose sales (They've since shut down)....

I don't go to B&M's unless to buy batteries these days, few weeks back went to one, the owner which I know through advocacy (I only go to shops that advocate for vaping) thought my build was a bit sketchy because it's much lower than what he's used to vaping on, Dual TriCore 28/40 Fused Claptons 0.18Ohms in a Mad Dog RDA which I fire at around 70w, told him to give it a go and after he vaped it he literally took a step back, his eyes got all big and was completely blown away by the warm flavorful vape, this guy definitely has tried lower builds as he does run a cloud comp circuit but I guess he had no clue they could be so flavorful since he always focused on vapor production with low builds. Literally sat there with him and he ordered it from Fasttech.. https://www.fasttech.com/p/7310500 https://www.fasttech.com/p/9617270

0.08 is a very low build though and is really pushing the limits of those batteries, personally knowing the risks I'd deem it unsafe for myself with the batteries he's using and likely the batteries are damaged to an extent, I'm not saying they'll explode or anything they will just have less mah and the voltage drop will be big, you have to remember that the lower your build is, the more amps you draw the faster your batteries will age, you'll end up getting less cycles and a lower quality vape which is why I think it's worth it to build a bit higher even if I am sacrificing a bit.

Canadian Vaper said:

You'd be surprised how many shops that don't see the point in vaping under 0.3 so they ignore everything under it and chastise anyone who vapes low, one shop that used to be in my area wouldn't sell coil heads under 0.5ohms even if it meant they would lose sales (They've since shut down)....

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its not negative or anything here, but theres a similar 'divide'. i get funny looks for using mech mods, no matter what (kayfun at 1.1 ohms on a tube, hammer of god with giant 30mm atty)...if you arent using the newest 'beast' variant from smok you get lots of 'how can you even vape that?' and no one is willing to even take a puff and find out what its like. one guy tried my hammer of god, and he bought a noisy cricket and a freakshow v2 and was converted (sadly hes gone now too).

Canadian Vaper said:

0.08 is a very low build though and is really pushing the limits of those batteries, personally knowing the risks I'd deem it unsafe for myself

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i dont have an issue with taking a few pulls off a 30a pinky at .08, but no more than that. no idea if he was using a pinky, or whether he knew what he was doing, or just copied someone elses setup...the thing that bugs me is that be brags about doing that, then says 'no one is smart enough to use mechs, they should be banned'...not only is he glorifying risky behavior, but also making mech mods sound scary and elite/hardcore. depending on who is listening to his bullshit, there are no good results from any of the things he says...either they think its a bomb and avoid learning anything to prove them wrong, or they think it sounds 'sick' to vape stupidly low builds and try to copy him and be hardcore brah. no one learns anything, some people are pushed to take a risk, and others are pushed away from finding all the great vapes you can get from mech mods. and this guy stands there 8 hours a day saying that shit makes me feel as close to flipping out as a re-wrapped 18650 with '40a 4000mah' written on the side.

Iliketurtles said:

TIL there are a buttload of idiots that work in vape shops and 'in general' idiots don't know that they are idiots. Often times they believe that they are fonts of knowledge.

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I work with a few.... https://rationalwiki.org/wiki/Dunning-Kruger_effect

mach1ne said:

, and others are pushed away from finding all the great vapes you can get from mech mods. and this guy stands there 8 hours a day saying that shit makes me feel as close to flipping out as a re-wrapped 18650 with '40a 4000mah' written on the side.

Click to expand...

Those wrongful elitist groups span across this industry and unfortunately it resides mostly in us consumers but it's not even necessarily our fault, I think it may have a lot to do with the cessation only brainwashing we've all had and the way regulations on vaping are turning out, how many times have I been told that my way of vaping is wrong from people who build ultra low to people who vape 2ohm coils, people think that just because something works for them IT MUST WORK FOR EVERYONE and this is where cessation only comes into play sort of, use the patch, well sorry it didn't work for me, use the pills I'm sorry they made me aggressive or I quit cold turkey if it worked for me it will work for you etc etc etc, the truth is everyone is different and that is why vaping is so successful is because there is so much variation, there's so many options that chances are at least one configuration will work for you it doesn't matter if it's a CE4 with a 2ohm coil, temperature control on a DNA, wattage mode or even a low build on a mech because you like to feel the voltage drop, they're all different variations and if something works for you, if something makes you content then continue what you're doing as long as it's relatively safe.

The relative safety of Mech's has been completely blown out of proportion when the truth is almost all mech failures have been with people using sub ohm tanks with floating positive pins and using atty's with too short of positive pin on a hybrid mech or just using sub-ohm tanks in general on a mech look at how unreliable smok's coils are I wouldn't put them anywhere near a mech but a good quality RTA Not a problem, when used correctly mech's are actually the safest vapes out there there's like pretty much nothing that can go wrong with them other than a dead short/improper battery usage.

When it comes to safety and pushing this technology to it's limits though we have to remember just how powerful the batteries we use are, I remember reading somewhere that there is about as much energy in most 18650's as there is in a 30 caliber bullet and that made me really think about it because at the time I was pushing my setup to its maximum and is the reason I moved from using HE4's to HB6's for my low builds, not only did I sacrifice mah for relative safety but I also improved the quality of my vape by using the right equipment.

You don't dig a ditch with a pitchfork you dig it with a shovel, if you're going to build low make sure you use the right tools and you'll have a better experience.

Canadian Vaper said:

0.08 is a very low build though and is really pushing the limits of those batteries,

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As a matter of true fact, if we can assume a 15% safety margin to account for the battery imbalance, and if we also take into account the voltage sag as well as the resistance of the mod, then 0.08 on a parallel mech with dual VTC5A batteries is still below the CDR.

Carambrda said:

As a matter of true fact, if we can assume a 15% safety margin to account for the battery imbalance, and if we also take into account the voltage sag as well as the resistance of the mod, then 0.08 on a parallel mech with dual VTC5A batteries is still below the CDR.

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Yep no problem as long as both batteries continue to make good contact.