Battery Safety and Amperage

[CliffCloff]

Hello guy's, New here to this forum. I've only read a few things off of here before. But I'm curious because things seem really counter intuitive to me. I was told if you're using a mechanical mod that you don't want to draw to many amps from it or bad .... will happen. So for example if you have an LG HG2 20A battery you don't want to build lower than 0.20 ohm's because already then even though I assume its not a big deal you over draw that by 0.50A... Yet my friend was telling me that the LG HG2 can handle doing to about 0.12 ohm's but if you do the math thats 34.17A. That's way higher than what they are marked at and yeah I know that that's it's CDR (continuous discharge rate) but still doesn't that mean that you shouldn't draw more than 20A. Or like I watched a video on youtube and the guys builds a 0.09 ohm dual parallel coil and is using Sony VTC5's and that's WAY WAY more than my example with the HG2's. I'm just confused by it and need someone to explain why its okay to draw that much power when I've been told that's how you blow the .... up

 

[bombastinator]

The internet is full of people doing unsafe things. Both of the users you mention risk destroying their batteries. Super low resistance coils don’t buy you anything anyway.

 

[CliffCloff]

If that's the case how do you safely build that low

 

[Tonee N]

I keep a quick sheet.

1.0 ohm = 4.2 amp draw
0.9 ohm = 4.6 amp draw
0.8 ohm = 5.2 amp draw
0.7 ohms = 6 amp draw
0.6 ohms = 7 amp draw
0.5 ohms = 8.4 amp draw
0.4 ohms = 10.5 amp draw
0.3 ohms = 14.0 amp draw
0.2 ohms = 21.0 amp draw
0.1 ohms = 42.0 amp draw
0.0 ohms = dead short = battery goes into thermal runaway

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[CliffCloff]

That's basically for single 18650 mechs though isn't it because I know that in parallel box mods the Amps stack and you can go to like 0.06 ohms

 

[dom qp]

That's basically for single 18650 mechs though isn't it because I know that in parallel box mods the Amps stack and you can go to like 0.06 ohms

If you want to use mechs you should know the math. Start with 0.06 resistance and work your way backwards to figure out the amp draw. See if it makes sense with what kind of batteries.

Just because you know someone who has a 0.06 build, or have read about someone with one, it doesn't mean it's within the safe zone for any batteries.

You need to be able to calculate it yourself and check.

And his chart isn't specific to single or dual batteries. 0.3 ohms will have a 14 amp draw regardless of how many batteries you have. It's like asking if the speed limit on a highway is for motorcycles only or if it's also for cars.

 

[Eskie]

Hello guy's, New here to this forum. I've only read a few things off of here before. But I'm curious because things seem really counter intuitive to me. I was told if you're using a mechanical mod that you don't want to draw to many amps from it or bad .... will happen. So for example if you have an LG HG2 20A battery you don't want to build lower than 0.20 ohm's because already then even though I assume its not a big deal you over draw that by 0.50A... Yet my friend was telling me that the LG HG2 can handle doing to about 0.12 ohm's but if you do the math thats 34.17A. That's way higher than what they are marked at and yeah I know that that's it's CDR (continuous discharge rate) but still doesn't that mean that you shouldn't draw more than 20A. Or like I watched a video on youtube and the guys builds a 0.09 ohm dual parallel coil and is using Sony VTC5's and that's WAY WAY more than my example with the HG2's. I'm just confused by it and need someone to explain why its okay to draw that much power when I've been told that's how you blow the .... up

If your friends or someone on YT told you to jump off a cliff, would you? You have it right, not them. If it’s YT change channels. If it’s a friend who refuses to listen to your logical response if that’s not safe, change the topic and hope they’ll be around with all their teeth the next time you plan to split a pizza.

 

[dom qp]

hope they’ll be around with all their teeth the next time you plan to split a pizza.

Share a pizza? I don't even do that and I live in a socialist country.

 

[Topwater Elvis]

That's basically for single 18650 mechs though isn't it because I know that in parallel box mods the Amps stack and you can go to like 0.06 ohms

If the cells in a dual battery mech are in parallel configuration the amps do not 'stack', meaning 2 20a CDR cells do not automagically provide 40a safely.
The safe way to use 2 cells in parallel should be considered as 1.5 times the amp rate of one cell, so 2 20a = 30ish amps.

As you can see by the following examples there is no way to use .06Ω safely.
4.2v / .06Ω = 70a
3.7v / .06Ω = 61.6a
3.2v / .06Ω = 53.3a

If you learn how to build efficiently for whatever power you have available you can get an identical vape at 1.2Ω & .12Ω.

It is never a good idea or safe to exceed the CDR of any cell...

 

[Baditude]

my friend was telling me that the LG HG2 can handle doing to about 0.12 ohm's but if you do the math thats 34.17A ...Or like I watched a video on youtube and the guys builds a 0.09 ohm dual parallel coil and is using Sony VTC5's and that's WAY WAY more than my example with the HG2's.

There's a lot of misinformation out there. You've heard the saying, "If its on the Internet...it must be true." Another one that makes more sense, "Just because you can, doesn't mean you should."

A lot of misinformed folks use what is called the "pulse" discharge rating of a battery and think they will be safe. We should only be using the "continuous discharge rating" (CDR).

Battery pulse ratings are useless! | E-Cigarette Forum
There are no 18650 batteries with a genuine rating over 30A!
Battery Amp Ratings: Continuous vs Pulse Ratings
​

Never blindly trust what anyone says is "safe", whether it is someone on YouTube, a vape shop employee, or a buddy. Know how to do the math yourself and be sure.

Explain it to the Dumb Noob: Ohm's Law Calculations for a Mechanical Mod

• As simple as it is to use, some people have a tough time grasping the concept. Recently revised to make it even simpler to understand.

Another thing that complicates this issue is how aftermarket batteries (Efest, AWT, MXJO, Imren, et al) exaggerate their amp ratings.

Are You Using a Rewrap (Rebranded) Battery?

• Learn what a rewrap cell is. If you are using a rebranded or after market cell, does that mean it is inferior, poor quality, or even dangerous? Which batteries are suspected to be rebranded batteries.

​

 

[zoiDman]

... Or like I watched a video on youtube and the guys builds a 0.09 ohm dual parallel coil and is using Sony VTC5's and that's WAY WAY more than my example with the HG2's. I'm just confused by it and need someone to explain why its okay to draw that much power when I've been told that's how you blow the .... up

Hi CliffCloff. Welcome to the ECF.

Here is a very Straight Forward explanation of what is going on in an Unregulated Parallel vs Series Mod.

Unregulated Parallel Box Mod vs. Unregulated Series Box Mod | Vaping Battery Safety

As to explaining Why it is OK to Exceed a Battery(s) CDR? I Don't have good explanation for you. Because in Simple Terms, there Isn't One.

If the Only Way someone can get thru their day is to use a Mech where the Build Draws More Amps than what a Battery(s) can handle, then they should be Using a Multi-Battery Regulated Mod.

Or maybe take a Serious look at Why they have to Build So Low?

 

[CliffCloff]

If you want to use mechs you should know the math. Start with 0.06 resistance and work your way backwards to figure out the amp draw. See if it makes sense with what kind of batteries.

Just because you know someone who has a 0.06 build, or have read about someone with one, it doesn't mean it's within the safe zone for any batteries.

You need to be able to calculate it yourself and check.

And his chart isn't specific to single or dual batteries. 0.3 ohms will have a 14 amp draw regardless of how many batteries you have. It's like asking if the speed limit on a highway is for motorcycles only or if it's also for cars.

I can do the math just fine its not about that it's just I'm making 100% sure what I believe to know is true

 

[CliffCloff]

Alright a lot of people are saying I need to know the math, in which I do... That wasnt what I was asking for. My main concern here was why people are saying it was safe to exceed a batteries CDR and say that I was okay to do so. Because I thought you weren't suppose to do that. I was really just looking for the simple answer of either "you can exceed it for this reason..." or "No these people are putting themselves at risk and that you are correct and aren't suppose to exceed the batteries limits or else that's when bad things happen"

 

[Beamslider]

Unless you have expensive lab equipment, what reads as .06 on some of the cheap ohm readers could just as well be a short.

 

[CliffCloff]

I also kind of want to get this straight to because someone said that you don't want to go by the batteries pulse discharge you only want to go by the CDR. So in that case would the only safe way of building low in a tube mech mod would be to get LG HB6's because they have a CDR of 30A. So you would be able to build as low as 0.14 ohms cause it will Draw 29A with a fully charged battery. But with like a parallel box you could go as low as 0.07 ohms with the same HB6 batteries since the amps stack on a parallel box

 

[vBDKv]

If you wanna use a mech mod, you really have to understand ohms law to the letter. If you don't, then read up on it or go with a regulated mod.

 

[CliffCloff]

If you wanna use a mech mod, you really have to understand ohms law to the letter. If you don't, then read up on it or go with a regulated mod.

I have 3 regulated ones and just bought my first unregulated the other day. It just a simple tube, nothing special. But from my knowledge I would say I have a fair understanding. Just quite literally I wanted to know why people say its safe to draw more power than what I believe to be as safe. But also to know if that it actually is safe and why or to be told that I was right and you aren't suppose to draw more power than what its CDR is

 

[Topwater Elvis]

I have 3 regulated ones and just bought my first unregulated the other day. It just a simple tube, nothing special. But from my knowledge I would say I have a fair understanding. Just quite literally I wanted to know why people say its safe to draw more power than what I believe to be as safe. But also to know if that it actually is safe and why or to be told that I was right and you aren't suppose to draw more power than what its CDR is

The first response to your thread answered that.

The internet is full of people doing unsafe things. Both of the users you mention risk destroying their batteries. Super low resistance coils don’t buy you anything anyway.

Risk destroying their batteries, risk having a battery vent, risk having one go into thermal runaway, risk having a catastrophic failure.

--- --- --- ---

It is never 'safe' to exceed the CDR of any cell, people that say it is are people you shouldn't take advice from / listen to.

 

[Walee]

Just like Mooch said in his video when he was asked if a setup is safe, "no". There is no safe. Understanding what the battery is doing is your best option. There is always risk. Having said that, if you decide to draw beyond the CDR of your battery(s) then your risk factor is going up, rapidly. Study what Mooch has published and it will all fall into place for you. Listen to some of these guys that have been building for mechs for a long time here and you will be able to get amazing vapes without having to stretch the safety zone. Listen to the cool dude in a loose mood with the bad-... build and you could end up with half a face.

 

[KenD]

I also kind of want to get this straight to because someone said that you don't want to go by the batteries pulse discharge you only want to go by the CDR. So in that case would the only safe way of building low in a tube mech mod would be to get LG HB6's because they have a CDR of 30A. So you would be able to build as low as 0.14 ohms cause it will Draw 29A with a fully charged battery. But with like a parallel box you could go as low as 0.07 ohms with the same HB6 batteries since the amps stack on a parallel box

There's no reasonably affordable way to read resistances that low accurately. No ohm reader or regulated mod will be accurate that low, and a 0.07 ohm reading is practically a dead short. Bad idea.

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