For a build that low, you'll need a battery with at least 30 amps continuous discharge. Most of the 26650 IMR
batteries available are only 20 amps continuous.
The single battery that I'm aware of with more than 30 amps is the
Panasonic 26650 CGR26650A with an advertised 50 amps continuous, but it has the least capacity (2650 mah) compared to the other 26650
batteries. Hard to find.
There is also the hard to find
Sony 26650 2800mah 30 amp battery.
Panasonic 26650 CGR2650A 2650mAh 50A
Sony 26650 2800mah 30A
Orbtronic 26650 5200mah 20A
Menke 26650 3800mah 20A
purple Efest 26650 4200mAh 20A
Battery Basics for Mods
I am of the mindset that you should leave a margin of safety when deciding what resistance coil to use. We probably place too much faith into cheap ohm readers in being precise and accurate. My own box ohm reader and my Provari make ohm readings that differ by 0.2 ohm; which one is more accurate? Also, a RDA's post screw unknowingly coming loose can greatly change the coil's resistance.
Everyone is free to set their own parameters, and I can only say what mine are. I try to never exceed 50% of the CDR (continuous discharge rating) of a fully charged battery (4.2v). So with 20A
batteries, that would be 10A. An
Ohm's Law calculator tells me that a .4 ohm build is as low as I would want to use with a 20 amp battery. The reason that I place a 50% limit is because as a battery ages the mAh of the battery degrades, as the mAh degrades so does the batteries c rating (amp limit). So down the road, your 20A battery may only be a 10A battery.
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