It would take 4 18650 Batteries to hit 300w. Imagine the battery life you'd get.
4 18650 can do 400W under optimal conditions. 3 have no problem with 300W. And some mfr are pushing the envelope with 230W with just two!
Even so, don't expect those upper numbers to be achievable across the board. Not happening for reasons I explain below. (I quoted/replied in an edit to my original text which is below)
As far as battery life, yes if you vape in the normal "sane" range say 80W, for example, the battery life should be fantastic on a four cell device. Should be, you're carrying around a power bank at this point!
you sure you truly understand how Watts is computed on regulated devices?
Yes of course. Most regulated devices are not linear. This is why when you see a real review (ex. Daniel) show charts they only achieve max output at a certain resistance. They will either be current limited where a build is low OR voltage limited where a build is on the higher side. Hence my "power band" reference. A truly, stiffly regulated power supply will show an increase in output current as load increases (resistance decreases) and its voltage on its terminals will stay constant. Since this is in theory and not achievable (in the absolute sense) in the real world due to conductor and contact resistance/loss limits, we don't see it happening. Of course these devices are built with safety first because in the real world there is little control to what happens with the end user. (i.e. the probability of a driver having its output driven into a direct short is very likely whether accidental or intentional!) And such abuse/abnormal operation results could have catastrophic consequences leading up to severe injury or death! This is why mechanicals have the potential to be so dangerous as experienced users know. And this is why Evolv, even with their utmost focus on control and safety, has implemented a line fuse in series with the positive lead on the board. You do NOT want a direct short across a 3S lipo that's rated at 60C pulse (or higher) in a box that's practically hermetically sealed (ex. Tuglyfe DNA 200). Might as well tightly clench a pack of jumping jacks in your hand while a friend lights the fuse!
The issue with these boxes having the lower limit of .1OHM hurts us that want to use RDAs with large staple fused clapton builds. Many will typically be below .1OHM. Sometimes as low as .05OHM. My DNAs will fire however I can hit the current limit at around 175W. Granted it's not where I want to be with chaining. And these builds are simply too low to run on single cell unregulated devices with any expectation of safe operation!
Take the Koopor Primus 300W. All of my sub 100 milliohm builds will throw the dreaded OHMS TOO LOW message. Switch to temp control and adjust the preheat to a desired level (ex. 200W) and it will fire just fine. But its the extra step and a mode of operation that it just wasn't designed for so I wouldn't recommend it to just anyone.
Another thing is inconsistency. When grabbed my first Alien 220W kit last October, I was thrilled that it fired my .07 build on my Kennedy 25. Used it for several weeks. Then, after switching to a TFV8 and Limitless XL (both with coils and/or builds never lower than .15) it simply refuses to drive the build on the Kennedy. And its electrical characteristic have not changed. I use a bench milliohm meter that's far more accurate than the typical coil master to verify and it's still rocking at 0.07 cold resistance. I can't really complain because the spec actually does claim min resistance of .1.
My COV Megavolt OTOH, has no problem firing it. It's a bit light with a max of 80W but workable. Just feels like an 8 firing on 6 cylinders. Works wonders on my Petri with 35W though.
I really need to pick up a Hohm Wrecker. I wish they had more power however the idea of doing TC on Kanthal is interesting!
And as far as race to higher power, if that's something you want it's been around for a while. Kilowatts, no multiple kW is no problem for a decent sized lipo and PWM board. I have one that can put out hundreds of amps. In theory it's over 3,000W. It's a conversation piece for sure but can drive some complex builds and produce vapor instantly where mere 200W DNAs sit for seconds before vapor production commences.
Comparing it to most commercially available boxes would be like comparing a 2500hp drag racer to a run of the mill Camaro or Charger.
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