- Status
The two most important things to know when choosing a battery and using sub-ohm coils for an UNREGULATED MECHANICAL mod is:
This is where Ohm's Law and using an Ohm's Law calculator comes into play. (NOTE: REGULATED MODS use a different formula than mechanical mods -- Watts Law.)
When you push the button on a mech mod, you complete a DC circuit. The battery in your mod doesn't know or doesn't care what the resistance of the coil wire is. All the battery knows is the circuit is complete and that it has to obey Ohms Law. It will attempt to fire the coil whether it has enough current or not. If it doesn't have enough current, it will over-heat and possibly vent or go into thermal runaway.
The more resistance you have with the coil, the higher the ohms will be and the less amps from the battery are needed. The lower the resistance of the coil, the lower the ohm will be and higher amps will be required to fire the coil. Note below, the lower the ohm, the higher the amp draw.
Bottom line: never exceed the battery's CDR (continuous discharge rate). To do so is abusing the battery and is dangerous.
To find out what current (amps) the coil will pull from the battery in a mechanical mod (known as the "amp draw"), you use an online Ohms Law Calculator. This is a remarkable tool. You insert 2 known values and it comes up with the 2 unknown values. For our purposes here, the Power value in watts is irrelevant for a mech mod.
Explain it to the Dumb Noob: Ohm's Law Calculations
Sony 18659VTC6 3000mAh 15 amp CDR
AW 18650 3000 mah 20 amp CDR
LG 18650HG2 3000mah 20 amp CDR
Sony 18650VTC5, 2600 mah 20 amp CDR
LG 18650HE4 2500 mah 20 amp CDR
Samsung 18650-25R, 2500 mah 20 amp CDR
(there is a blue wrapped 25R with identical specs)
Sony 18650VTC4, 2100 mah 23 amp CDR
Sony 18650VTC5A, 2500 mah 25 amp CDR
LG18650HB6 1500mah 30 amp CDR
LG18650HB2 1500mAh 30 amp CDR
LG18650HB4 1500mAh 30 amp CDR
Sony 18650VTC3 1500mAh 30 amp CDR
Of the batteries you listed vtc 4, vtc 5a, lg hb6, or samsung 25r:
- know the true amp limit of the battery you have
- know the amp draw of your coil.
This is where Ohm's Law and using an Ohm's Law calculator comes into play. (NOTE: REGULATED MODS use a different formula than mechanical mods -- Watts Law.)
When you push the button on a mech mod, you complete a DC circuit. The battery in your mod doesn't know or doesn't care what the resistance of the coil wire is. All the battery knows is the circuit is complete and that it has to obey Ohms Law. It will attempt to fire the coil whether it has enough current or not. If it doesn't have enough current, it will over-heat and possibly vent or go into thermal runaway.
The more resistance you have with the coil, the higher the ohms will be and the less amps from the battery are needed. The lower the resistance of the coil, the lower the ohm will be and higher amps will be required to fire the coil. Note below, the lower the ohm, the higher the amp draw.
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
0.15 ohms = 28 amp draw
0.1 ohms = 42.0 amp draw (no single battery has more than 30A)
0.0 ohms = dead short = battery goes into thermal runaway
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
0.15 ohms = 28 amp draw
0.1 ohms = 42.0 amp draw (no single battery has more than 30A)
0.0 ohms = dead short = battery goes into thermal runaway
Bottom line: never exceed the battery's CDR (continuous discharge rate). To do so is abusing the battery and is dangerous.
To find out what current (amps) the coil will pull from the battery in a mechanical mod (known as the "amp draw"), you use an online Ohms Law Calculator. This is a remarkable tool. You insert 2 known values and it comes up with the 2 unknown values. For our purposes here, the Power value in watts is irrelevant for a mech mod.
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. Recently revised to be even more simple. Warning: Includes graphic photos of mod explosions.
Sony 18659VTC6 3000mAh 15 amp CDR
AW 18650 3000 mah 20 amp CDR
LG 18650HG2 3000mah 20 amp CDR
Sony 18650VTC5, 2600 mah 20 amp CDR
LG 18650HE4 2500 mah 20 amp CDR
Samsung 18650-25R, 2500 mah 20 amp CDR
(there is a blue wrapped 25R with identical specs)
Sony 18650VTC4, 2100 mah 23 amp CDR
Sony 18650VTC5A, 2500 mah 25 amp CDR
LG18650HB6 1500mah 30 amp CDR
LG18650HB2 1500mAh 30 amp CDR
LG18650HB4 1500mAh 30 amp CDR
Sony 18650VTC3 1500mAh 30 amp CDR
Of the batteries you listed vtc 4, vtc 5a, lg hb6, or samsung 25r:
The vtc4 and Samsung25R are 23 and 20 amps CDR respectably.
The VTC5A is a 25 amp CDR.
The HB6 is a 30 amp CDR.
The HB6 has the highest CDR, but only has 1500 mAh. The VTC5A has 25A with 2600 mAh, so it probably is the most versatile battery of the bunch.
The VTC5A is a 25 amp CDR.
The HB6 is a 30 amp CDR.
The HB6 has the highest CDR, but only has 1500 mAh. The VTC5A has 25A with 2600 mAh, so it probably is the most versatile battery of the bunch.
Last edited:
You don't give enough info to give any recommendations.
The cell you need when using a mechanical depends on the resistance range you intend to use.
I'd need to know a lot more before making a recommendation, like what mod and atty, how are you going to coil it, etc. Right now my recommendation is "run away."
Welcome and glad you joined.
Might want to read the second item on the list which will supplement the other posts:
frequently_asked_questions - electronic_cigarette
- Status
Similar threads
