So I've become interested in Sub-Ohm vaping and Mech Mods but want to be sure that I take as much safety precautions as I can. After searching online and watching many videos, my understanding of Ohm's law and battery safety and watts and voltage and resistance ect. has turned into more of a confusion. The other day I purchased a clone mod and rda that comes with a battery+charger so I have something to kind of learn on. But Im baffled with the amount of complexity in electric that goes into these simple mechanical mods. I guess what im really asking is for a simple simple summary of these concepts. Like how do I figure out what a safe range of resistances are for a certain battery? Thanks so much!
Newbie Sub-Ohm Questions
- Thread starter xfrancis333
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Hello and welcome to the forum xfrancis333. Glad to have you here!
If you are new to mech mods and rebuildables I highly recommend you spend some time with Baditude (one of our resident battery experts) and visit his blogs. You are now 100% in control of your own safety (and others around you). Make sure you purchase an ohm reader and a voltmeter or DMM so you can measure your builds, check for shorts and measure the remaining charge on your batteries.
Baditudes Blogs. The blogs regarding mods and rebuildables are listed below:
BATTERIES
9. Battery Basics for Mods: IMR or Protected ICR?
* Another essential read to understand which batteries are safe to use in mechanical and regulated mods. Includes a frequently updated list of recommended safe-chemistry, high-drain batteries with their specifications.
17. Purple Efest Batteries Not As Advertised
* A cautionary blog that reveals that the purple Efest batteries may not have the specifications advertised. Also includes a commentary on "continuous discharge ratings" vs "pulse discharge ratings" of battery specs.
OHM'S LAW
14. Ohm's Law for Dummies (Vapers)
* My attempt at explaining Ohm's Law in layman terms and how it relates to vaping.
16. Explain it to the Dumb Noob: Ohm's Law Calculations
* As simple as it is to use, some people have a tough time grasping the concept. Warning: Includes graphic photos of mod explosions.
BATTERIES - WHERE TO BUY
Only buy batteries from a reputable supplier (not ebay or Amazon) as there are many counterfeit batteries being sold. Here are several reputable battery suppliers in the US.
* RTD Vapor
* Illumination Supply
* Lighthound
* Orbtronics
If you are new to mech mods and rebuildables I highly recommend you spend some time with Baditude (one of our resident battery experts) and visit his blogs. You are now 100% in control of your own safety (and others around you). Make sure you purchase an ohm reader and a voltmeter or DMM so you can measure your builds, check for shorts and measure the remaining charge on your batteries.
Baditudes Blogs. The blogs regarding mods and rebuildables are listed below:
BATTERIES
9. Battery Basics for Mods: IMR or Protected ICR?
* Another essential read to understand which batteries are safe to use in mechanical and regulated mods. Includes a frequently updated list of recommended safe-chemistry, high-drain batteries with their specifications.
17. Purple Efest Batteries Not As Advertised
* A cautionary blog that reveals that the purple Efest batteries may not have the specifications advertised. Also includes a commentary on "continuous discharge ratings" vs "pulse discharge ratings" of battery specs.
OHM'S LAW
14. Ohm's Law for Dummies (Vapers)
* My attempt at explaining Ohm's Law in layman terms and how it relates to vaping.
16. Explain it to the Dumb Noob: Ohm's Law Calculations
* As simple as it is to use, some people have a tough time grasping the concept. Warning: Includes graphic photos of mod explosions.
BATTERIES - WHERE TO BUY
Only buy batteries from a reputable supplier (not ebay or Amazon) as there are many counterfeit batteries being sold. Here are several reputable battery suppliers in the US.
* RTD Vapor
* Illumination Supply
* Lighthound
* Orbtronics
It's actually a little easier than you may think. First off: What battery are you using? The batteries for sub ohming, and mechanical mods dictate EVERYTHING YOU CAN DO. I use only purple efest 18650 2500mah which are a continuous drain of 20amps (They advertise as 35amp but that's BS and pulse limits not continuous), so I build my coils to be battery limit minus 2 amps for a fudge factor.
IE:
20Amp Continuous Draw on Battery
Ohms Law: 0.23ohms @ 4.2v (Fresh Charge Battery) = 18.26 amp draw
Slightly less than 2 amp play but still in my safe zone.
10 Amp continuous draw battery:
Ohms Law: 0.50ohms @ 4.2v (Fresh Charge Battery) = 8.4amp draw
That's how I figure out my safe zones. ALWAYS better to put enough space for a fudge factor.
IE:
20Amp Continuous Draw on Battery
Ohms Law: 0.23ohms @ 4.2v (Fresh Charge Battery) = 18.26 amp draw
Slightly less than 2 amp play but still in my safe zone.
10 Amp continuous draw battery:
Ohms Law: 0.50ohms @ 4.2v (Fresh Charge Battery) = 8.4amp draw
That's how I figure out my safe zones. ALWAYS better to put enough space for a fudge factor.
Both above posts are great. Read study and understand them thoroughly. There are ohms law apps for your smartphone/tablet. Use them. I don't want to oversimplify anything, hence me telling you to understand the above posts. Know a few things for sure though. 1. The amp rating of your battery. Sony VTC's are great, Samsung 25r, etc. But know what that amp limit is and buy reputable batteries. 2. Know how to check your ohms of your coils. Always check for shorts and build coils safe. If your battery has a 20A limit, don't go building a .2 ohm coil or whatever would exceed that limit. Truthfully, you shouldn't have to. Seems to me a lot of people lately like to push the limits, but you'd be surprised what a good .4 or .5 or so coil can do and how it can preform. 3. Always assume a full charge on your battery for inputing your ohms law equation. I always input 4.2 volts.
Learn learn learn.... then when you feel comfortable with the knowledge you have build. Don't dive in and assume. And there's tons of people on here always glad to help. I'd like to see people ask and learn versus just throwing things together without knowing what they're doing, so kudos to you there and good luck!
Learn learn learn.... then when you feel comfortable with the knowledge you have build. Don't dive in and assume. And there's tons of people on here always glad to help. I'd like to see people ask and learn versus just throwing things together without knowing what they're doing, so kudos to you there and good luck!
Battery drain | Steam Engine | free vaping calculators
All you need to know about what your battery can handle
Coil wrapping | Steam Engine | free vaping calculators
What you need to know about hitting the resistance target your battery can handle. It isn't that hard. Lots of nuances but the basics are very very simple.
All you need to know about what your battery can handle
Coil wrapping | Steam Engine | free vaping calculators
What you need to know about hitting the resistance target your battery can handle. It isn't that hard. Lots of nuances but the basics are very very simple.
I suggest getting an ohms law calculator app for your cell-phone or tablet it gives you all the parameters of your build enter 2 values like the resistance and then the 4.2 volt that a freshly charged battery maxes out at and boom it will tell you the watt and amperage load of your build and it is best not to build right at the continuous drain amperage limit as it doesn't leave room for fluctuation in ohm rates because as you vape on your builds they can go up or down with use. Metal's molecular structure changes when it is continuously heated and cooled and this can change the resistance rates. I use Sony VTC5 18650 batteries they are pretty much king of the heap when it comes to sub-ohm batteries they are 30 amp continuous drain and 150amp pulse so virtually the lowest build you would want to build is a .15 using the Sony VTC5 battery which is a 28amp drain and works out to 117.6 watts this is going to be a very hot vape and to most people an intolerable temperature. I run my builds around .25 to .45 ohms depending on the atty and what I'm looking for from the build be it clouds or flavor. A .25 ohm build on a freshly charged 4.2 volt battery is a 70.55 watt build a .45 ohm build is 39.2 watts and 9.3 amps so the battery isn't having to work as hard and the temperature is considerably cooler.
You -definitely- need a meter to make sure you don't go below your target resistance. Any good quality ohm reader will do as a general rule, but get 2 to be sure. Check after wrapping, after crimping, and after wicking and juicing as all of these factors can alter your readings. Remember though, what you're trying to read is largely discarded in the electrical world as no resistance, because ohms that low aren't usually used in most other practical applications, so variance is hit or miss. Be safe, first and foremost.
Doesn't matter what device you use. You should ALWAYS use an ohm reader or multimeter so you have a double check. Ohm readers can malfunction, considering most of them are $15 or less devices. You willing to trust a battery vent or explosion to $15? I'm not. I literally (Call me paranoid all you like) check mine on my ohm reader and my multimeter on anything below 0.5, that way I know there are no flaws or janky readings.
Thanks for all the great replies! So generally speaking the higher the resistance, the safer? I plan on only using 18650s for now, so should I use 4.2v as the max voltage in all my calculations? Also how do I determine the continuous drain (in amps) of a battery?
The specs of the battery that comes with the "kit" I bought:
Battery Specifications:
Capacity:2200mah
Voltage :3.7V
Charge cut-off voltage:4.2V
Discharge cut-off voltage:2.75V
Standard charging:0.2C(with max. voltage of 4.2V and cut-off current at 0.01C)
Standard discharging:0.2C(Constant current at 0.2C with min. voltage of 2.75V)
Max Discharge current:3C 5C 10C 15C
Impedance:≤20mΩ(Internal resistance measured at AC 1KHZ after 50% SOC)
I do know that most likely the battery/charger is not the best and I plan on purchasing some sony batteries because Ive heard so much good stuff about them. But at this point I would just like to try this whole sub-ohm vaping thing out and didnt want to drain the old wallet. Again these replies are fantastic so thanks!!
The specs of the battery that comes with the "kit" I bought:
Battery Specifications:
Capacity:2200mah
Voltage :3.7V
Charge cut-off voltage:4.2V
Discharge cut-off voltage:2.75V
Standard charging:0.2C(with max. voltage of 4.2V and cut-off current at 0.01C)
Standard discharging:0.2C(Constant current at 0.2C with min. voltage of 2.75V)
Max Discharge current:3C 5C 10C 15C
Impedance:≤20mΩ(Internal resistance measured at AC 1KHZ after 50% SOC)
I do know that most likely the battery/charger is not the best and I plan on purchasing some sony batteries because Ive heard so much good stuff about them. But at this point I would just like to try this whole sub-ohm vaping thing out and didnt want to drain the old wallet. Again these replies are fantastic so thanks!!
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I got a Assembled Volt Indicator - Rev 2 - Gulf Coast Vapor from madvapes. Is that what I need?
Personally I would not use an unknown battery from a kit for sub ohm. $10 or so for a legit known battery is far cheaper than the deductable on my health insurance if I were to melt my face. Legit Sony's are extremely hard to find and the few places that have them are overpriced. There are other good batteries out there for a fair price from reputable trustworthy vendors. Batteries are the one thing you do NOT want to cheap out on.
Is there any hope in finding some nice batteries with a charger on eBay of Amazon? Can these be purchased in hardware stores? Or is my only option in finding a decent battery to get it online from a reputable ecig website?
Stay away from eBay when it comes to batteries, there are a lot of fakes out there. Best to be safe and purchase from one of the vendors referenced in Susan's post (top of the thread).
I got my Samsung 25r's for like $7.00 from Orbtronic, and they rock. Ordered 3, they even came with 2 carrying cases.
I'd just get 'em online from a specialized supplier, like most ecig stuff I'll ever buy.
I'd just get 'em online from a specialized supplier, like most ecig stuff I'll ever buy.
I would not buy batteries from a Ebay or Amazon supplier unless I knew their reputation and there are none that I know are good. Susan gave examples of known good battery suppliers in her post.
Illumination Supply
RTD Vapor
Lighthound
Orbtronic
Battery Junction
Illumination Supply is selling Samsung 25R 18650's 20 amp continuous for $6.00, so there's really no need to look for a better deal.
I'm out of the loop with chargers, but pretty much anything Xtar makes is good. A lot of people have Nitecore Intelichargers and do well with them. I think you can get one for under $20.
I have had problems with my nicore over charging batteries. I replaced it with a luc v4 from Lightning Vapes — Lightning Vapes - Great Products, Lightning Fast Shipping! Silica Wick, Kanthal Wire, Stainless Steel Mesh, Ekowool and More! for about $22 with free shipping using the LV20 coupn code. The also have samsung 25r batteries for $8.
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