Hello so I just got my first mech but I'm waiting on what will be my mech only batteries to arrive, in the mean time I wanted to build some coils for it. I just wanted advice on how to tell when my battery is getting low and it's time to switch it to a fresh one? I plan on starting with 0.3 ohm builds to be on safe side. I'll have 20Amp batteries so at 3.7v that's pulling around 15 amps from the battery. It's my understanding that trying to use a battery that's basically dead or super low isn't exactly like explosion dangerous but the battery heats up bad? Any info is appreciated thanks, also it'll be the Wismec Reuleaux RX Machina mod with the bravo RTA.
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What batteries did you order? It is of paramount importance to use genuine high quality batteries from a reputable source.
Most people just get used to the change in power and will be able to tell when the voltage is sufficiently low to need a fresh battery from experience. You could also use a voltmeter to test your battery to see what charge is left.
You should calculate your peak amperage at 4.2 volts as this is the value when the battery is fully charged. 3.7 volts represents the nominal voltage, meaning the value on the discharge curve that the battery will spend most of it's life.
Use the equations below to find the relevant values or use steam-engine.
I = amps V = volts R = resistance P = watts
To find the amp draw use I=V/R
Eg. divide 4.2v by 0.3Ω = 14 amps
To find the wattage use P=V²/R
Eg. 4.2v multiplied by 4.2v divided by 0.3Ω = 58.8 watts
An 18650 is fully charged at 4.2 volts and can be considered discharged at 3.0 volts. Discharging below 3.0 volts will stress the battery, and below 2.5 volts damage it.
18650s will may get warm during use depending on how hard you are pushing them. They may also get warm during charging especially if you use more than 0.5 amps.
Please take the time to read and digest the information in the links below. Mechs have no safety features and in the wrong can be dangerous. Be informed, be safe.
Understanding Battery Capability/Capacity | E-Cigarette Forum
Battery Safety | E-Cigarette Forum
(8) A Beginner's Guide to Your First Mechanical Mod | E-Cigarette Forum
(14) Ohm's Law Explained for Vapers | E-Cigarette Forum
Most people just get used to the change in power and will be able to tell when the voltage is sufficiently low to need a fresh battery from experience. You could also use a voltmeter to test your battery to see what charge is left.
You should calculate your peak amperage at 4.2 volts as this is the value when the battery is fully charged. 3.7 volts represents the nominal voltage, meaning the value on the discharge curve that the battery will spend most of it's life.
Use the equations below to find the relevant values or use steam-engine.
I = amps V = volts R = resistance P = watts
To find the amp draw use I=V/R
Eg. divide 4.2v by 0.3Ω = 14 amps
To find the wattage use P=V²/R
Eg. 4.2v multiplied by 4.2v divided by 0.3Ω = 58.8 watts
An 18650 is fully charged at 4.2 volts and can be considered discharged at 3.0 volts. Discharging below 3.0 volts will stress the battery, and below 2.5 volts damage it.
18650s will may get warm during use depending on how hard you are pushing them. They may also get warm during charging especially if you use more than 0.5 amps.
Please take the time to read and digest the information in the links below. Mechs have no safety features and in the wrong can be dangerous. Be informed, be safe.
Understanding Battery Capability/Capacity | E-Cigarette Forum
Battery Safety | E-Cigarette Forum
(8) A Beginner's Guide to Your First Mechanical Mod | E-Cigarette Forum
(14) Ohm's Law Explained for Vapers | E-Cigarette Forum
Howdy and welcome 
On a mech. Battery behaves a bit like a balooon. Starts out big and puffy and gradually fades away. You’ll want to change batteries when you aren’t getting a decent vape out of it any more. At least that’s what I generally do.
On a mech. Battery behaves a bit like a balooon. Starts out big and puffy and gradually fades away. You’ll want to change batteries when you aren’t getting a decent vape out of it any more. At least that’s what I generally do.
Yeah thanks I think I've got a good grasp of everything, I check what Amps will be put out on a build before i even start making the wrap/clapton etc. I'm using
LG HE2 18650 2500mAh 20A Battery from IMRbatteries
That is indeed a good 20 amp cell.
LG HE2 20A 2500mAh 18650 Bench Retest Results...a very good 20A battery
https://www.e-cigarette-forum.com/t...etest-results-a-very-good-20a-battery.716469/
Yes you can model a build in steam-engine before you even touch your spool of wire. Once you have installed the coil you should also check the build on an ohm meter to check you hit the desired resistance, the coil is well secured and stable, and most importantly there is not a short.
Feel free to ask any more questions that might come to mind.
LG HE2 20A 2500mAh 18650 Bench Retest Results...a very good 20A battery
https://www.e-cigarette-forum.com/t...etest-results-a-very-good-20a-battery.716469/
Yes you can model a build in steam-engine before you even touch your spool of wire. Once you have installed the coil you should also check the build on an ohm meter to check you hit the desired resistance, the coil is well secured and stable, and most importantly there is not a short.
Feel free to ask any more questions that might come to mind.
Thanks, like I said i've been building coils for a while now, and since I was on a regulated device so I didn't really need to worry about battery safety. I understand ohms law and what not I just wanted to be super sure since it's my first mech.
<sigh> Choosing the right battery is also important on a regulated device, but the way you work out the amp draw is different.
Ohms/Watts Law - Calculating safe amp usage | E-Cigarette Forum
https://www.e-cigarette-forum.com/blog-entry/ohms-watts-law-calculating-safe-amp-usage.7562/
Ohms/Watts Law - Calculating safe amp usage | E-Cigarette Forum
https://www.e-cigarette-forum.com/blog-entry/ohms-watts-law-calculating-safe-amp-usage.7562/
So I've had two of the four new batteries I bought on a charger for probably about 3 hours now and they've only gone from 3.2 v to 3.9, is it just me or is that unusually slow? I've had the same previous batteries for over a year so I don't remember if they took this long for their initial charge when they were new
You can with a VTC5 which I run in my mech with dual parallel 24 g kanthal coils at .13 ohms super safely build .3 ohms, not only will you not pulse the battery you will not exceed the amp limit of 30. You can safely use that battery until .2 ohms, anything under that is personal preference and wether you are educated enough with what your vaping to know how to use it. Just read lots about ohms and battery’s before getting below .3 ohms
The vtc5 is not a 30-amp battery. It's 20 amps. 0.13 is definitely lower than recommended on it.
Sent from my Thor E using Tapatalk
Maybe you should follow your own advice. I have a pet peeve for misinformed folks giving bad advice to novices.
Sony VTC5 2500mAh 18650 Retest Results...a great 20A 2600mAh battery
Battery Voltage Meter attaches to the mod's 510 connector to measure realtime battery voltage. Batteries should never be routinely drained lower than 3.4 volts. Drained below 2.5 volts will likely destroy the battery.
A Beginner's Guide to Your First Mechanical Mod
Explain it to the Dumb Noob: Ohm's Law Calculations
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Hey so I've been using the mech for almost a week now and I've got to say the hits coming off of it are very nice! I'm unsure if this applies to mechs or what but it seems my coils have gunked up faster than they did when I was vaping the same juice on my squonker, is this a trend for you as well or are my coils just being funky? Normally I could go through almost 7 ml of juice before the coils gunked up bad and I've gone through about 6 maybe? I've noticed the hits aren't that great when the battery drops to around 3.6 V so that's about when I swap out. Maybe it's because of ramp time I'm unsure.
Pulse ratings are meaningless. Any “max” or “pulse” rating is useless unless we know the length of the pulse, the time between the pulses, and the criteria used to set the rating (Voltage sag? Temperature? Run time? A combination of those?). Without knowing these factors, and all companies using the same pulse lengths, rest times, and criteria, we can’t use the max/pulse ratings for comparing any batteries. They are useless.
Battery Amp Ratings: Continuous vs Pulse Ratings
Battery pulse ratings are useless! | E-Cigarette Forum
There are no 18650 batteries with a genuine rating over 30A!
If you are basing your builds on the so-called pulse ratings of your battery, then your setup is instantly over-specced. Only use the continuous discharge rate (CDR). This is the industry standard.
Building to a pulse rating is akin to always driving your car in redline, or flooring it at every stop sign or stop light. How long will your car's engine last doing that? How long will your battery last using a pulse rating?
You are abusing (misusing) your batteries. Ain't no way around that.
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