Sub ohm and batteries

[Nick_808]

Hey guys I'm still kinda new to sub ohming & the lowest i have gone is .5 ohms on a dual coil w/ normal 28g kanthal in my cartel stillare atty with panzer mod and my battery is an Efest 3.7V 2500 mah imr 18650 35Amp battery and everything vapes fine. BUT MY QUESTION TODAY is I just got some Gplat 24G wires and i wanted to try go to a lower ohm maybe around .1 to like .2 or somewhere in between and i was just curious if my batteries are hardcore enough to handle that low of sub ohm i just wanted to make sure cause i read somewhere if i don't have enough power and try to build really low ohms it could be a bad combo. please let me know or if you have any tips about sub ohming and what not post it here thanks again vape on

 

[Papa_Lazarou]

Not for nothing, my friend, but you really should know Ohm's Law like the back of your hand for times like this.

You can calculate the current (amps) you need to fire the atty as I = V/R (amp = voltage / resistance). Assuming a full battery (4.2V) and a .1 ohm coil build, you are looking at 42 amps. You read that right. At .2 ohms, you're looking at 21 amps. You should also leave about 20% headroom in terms of your battery's limit, so that would mean about 50 amps with the .1 and 25 amps with the .2.

Now, your bat will probably not stay at >4V for very long and what we do is more like pulsing (as opposed to continuous use), so the battery is not stressed at that maximum level, really (theoretically).

BUT... and this is a big, hairy but... why take the risk? No one has been able to convince me that a .1 ohm coil is justified. Duals (or quads) netting out at .4 will give you all you can handle. I say this because I care about vapers (not to scold). It can get dangerous, man.

 

[Susan~S]

No, your batteries are not safe for low sub-ohm. The Sony VTC5 batteries are recommended. I wouldn't go below 0.3 ohm for safety reasons (but that's me) -- I actually prefer 0.5 ohm and higher.

EFEST
If your batteries are the purple Efest 18650 2500mAh 35A batteries -- they are not 35A continuous. They are really rebranded LG18650HE2 2500mAh 20 amp continuous batteries. Source: Baditudes Blog Battery Basics for Mods: IMR or Protected ICR?

Here is another warning that was posted on ECF regarding another purple Efest battery: Efest 3100mAh battery caution

WHERE TO GET BATTERIES
Only buy from a reputable dealer (not ebay or Amazon) as there are many counterfeit batteries being sold.
How to Spot Fake Sony Batteries

Here are a few reputable suppliers in the US.
* Illumination Supply
* Lighthound
* Orbtronics
* RTD Vapor

 

[antony73]

Papa_Lazarou: "Like the back of your hand." Well said.

In my opinion, a person must know the formula so well that all they need is a calculator. In time, memorizing certain equations becomes second nature.

Do the math, enjoy it or move to regulated.

Sent from my GT-S7562 using Tapatalk

 

[Nick_808]

@papa_lazarou so your saying to be safe .4 ohms is the lowest that i should go with the current batteries that i have now ?!?!? And to everyone else thank you i appreciate the info i guess ill look into some higher amp batteries if i want to build below .4 ish i might be naughty and build .3 but ill respect what you said and study up on that ohms law THANK YOU !!

 

[Nick_808]

And are the efest purple batteries i have generic or something what does it mean re branded do they just take the sony batteries and put their logo over it or what lol

 

[Susan~S]

And are the efest purple batteries i have generic or something what does it mean re branded do they just take the sony batteries and put their logo over it or what lol

Check your "period" key. It may be stuck. It's hard to read when you have a bunch of "run on sentences".

Efest took a LG18650HE2 2500mAh 20A battery and put their own wrapper on it. They labeled it as 35A (which was the pulse amp of the LG battery). The Sony counterfeit batteries use a wrapper that looks like a Sony wrapper and is labeled Sony but is not a Sony battery. If you pull up the link I posted you will see the differences.

As far as how low you can reasonably go with your Efest batteries (20A limitation) - use your ohms law calculator to figure it out (allowing 20% safety margin).

 

[Papa_Lazarou]

@papa_lazarou so your saying to be safe .4 ohms is the lowest that i should go with the current batteries that i have now ?!?!?

As far as how low you can reasonably go with your Efest batteries (20A limitation) - use your ohms law calculator to figure it out (allowing 20% safety margin).

^^ this, brother.

 

[Ryedan]

Lots of good advice here Nick_808 .

Here's a Ohm's law online calculator. Your batteries will be pretty close to 4.2 volts when fully charged so that's what you enter for amp draw calculations. You will have voltage drop at the coil, but the battery will see the whole 4.2V. 16 amps is 80% of 20A so enter 16A and click on 'calculate'. You'll see that you with a 0.2625 ohm coil you'll be drawing 16A and making 67 watts.

Consider how accurate your ohm meter is and add that uncertainty to the minimum resistance you make. If you build 0.3-0.4 ohms you'll be in the 35-45 watt range with fresh batteries taking voltage drop into account. I prefer to stay between 0.4-.05 ohms myself with dual coils and Sony VTC batteries, but if it turns out you like it that aggressive, vape on. If you ever find your battery heating up, you've either made a mistake and gone too low in resistance or you have a short somewhere in your setup, in the atty or the mod. Stop immediately and fix it. If you ever find your mod heating up, you have too much resistance between mod contact surfaces. Again, stop and fix it.

If you would like more information, there is a lot here: One Stop Reference Shop For New and Experienced Vapers. Definitely read the group of links starting with 'Battery Info 1 Thanks to Baditude'.

Vape safe

 

[JKnight5]

If it hasn't been mentioned yet, download the ohms law calculator app for iphone or android. It's a lifesaver. It does all the work for you.

 

[Baditude]

Ohm's Law for Dummies

Cloud Chasing is Dangerous

 

[TomGeorge]

No, your batteries are not safe for low sub-ohm. The Sony VTC5 batteries are recommended. I wouldn't go below 0.3 ohm for safety reasons (but that's me) -- I actually prefer 0.5 ohm and higher.

EFEST
If your batteries are the purple Efest 18650 2500mAh 35A batteries -- they are not 35A continuous. They are really rebranded LG18650HE2 2500mAh 20 amp continuous batteries. Source: Baditudes Blog Battery Basics for Mods: IMR or Protected ICR?

Here is another warning that was posted on ECF regarding another purple Efest battery: Efest 3100mAh battery caution

WHERE TO GET BATTERIES
Only buy from a reputable dealer (not ebay or Amazon) as there are many counterfeit batteries being sold.
How to Spot Fake Sony Batteries

Here are a few reputable suppliers in the US.
* Illumination Supply
* Lighthound
* Orbtronics
* RTD Vapor

Sony VTC 5's dont exist. Sony never made VTC 5's. the company's they subcontracted their batteries out to made them and put a sony wrapper on them with no input from sony at all. (you can go to the sony website US and global and look for yourself)

That being said, I use vtc5's and purple efest and regularly go as low as .2 but find .3 or .35 ohms to be a better vape.

Whatever you decide OP, be careful, read up, watch some videos, and if your mod starts getting really hot, take it apart and scrap your build

 

[Nick_808]

@ryedan thank you for that info and that ohm calc that helped alot vape on brother ! i just rolled a single coil .34 ohms i did 10 wraps with my gplat 24g wire i thought 10 wraps would be higher resistance then .34 but these wires kick ... and so far my mod is doing fine no heating up and what not but ill definitely be careful thanks again guys really appreciate the info

 

[Ryedan]

@ryedan thank you for that info and that ohm calc that helped alot vape on brother ! i just rolled a single coil .34 ohms i did 10 wraps with my gplat 24g wire i thought 10 wraps would be higher resistance then .34 but these wires kick ... and so far my mod is doing fine no heating up and what not but ill definitely be careful thanks again guys really appreciate the info

You're welcome Nick. Glad it helped and that you're where you want to be with it .

Vape on my friend