Ok. I already have a couple efest imr 18350 batteries that I'll be using as well as an ohm meter to test coils and a luc efest charger.
I've been doing a lot of reading between my posts in THIS thread, and I'm starting to get a better picture. I still have 3 questions though.
1) how do I determine the continuous, spike, and resting voltage of my battery?
2) one of the blog posts on battery safety says that the safest battery is the biggest one your mod can accommodate. If I build coils with the limitations of a 18350 in mind (not sub ohming) why is that more dangerous than using a 18650 with an appropriately designed coil?
3) what is considered a "safe" distance from the maximum wattage of a setup? For example, if my battery is putting out 4.2v at the highest with a rating of 10c, and my coil is at 1.8 ohms; that gives me a current of 9.8 watts((4.2*4.2)/1.8 right? ). Is that considered safe if it's only 2 tenths away from the max of what the battery can handle?
a couple people beat me to the answers and they are good answers. But for point 1) yes that is important but what I meant get an ohm checker to check the ohms (resistance) on your atty. Thats a very important number to not guesstimate especially the lower you get. For example if you guess and your coil comes out to about .4 ohms, that draws 10.5 amps which you should be fine with lets say a 2000mAh Efest which can push 10amps continuous (lets forget about the burst rating for now) but if you guess and hit .2 ohms instead of .4 then you would be pulling 21 amps, which is well over the 10A continuous rating (and most likely even over the burst amp rating too!) So you need a multimeter or ohm checker to tell the resistance of your atty for sure if your going sub ohms.
2) Its just that the higher rating you have would naturally be more safe. More margin for error. You will be fine running a .8 on a 350 battery, but if you run it on a 650 then you are putting less stress on the battery as it is farther away from the limitations of the battery.
3) For safety you want to look at AMPS not watts. The C rating of the battery is explained here
The C measurement unit can be a bit hard to understand. The C measurement indicates a current value relative to the batteries overall capacity. For instance, a 2,600 mAh battery with a maximum discharge rating of 1C can handle a maximum current draw of 2.6 amperes or 2,600 mAh; pretty simple. Change the rating to 2C and the maximum discharge rate is 5.2 amperes, 3C is 7.8 amperes, so on and so forth.
and that is what the battery can handle.
for your example. A = 4.2v/1.8Ω So with a 1.8 ohm atty on a fully charged battery putting out 4.2 volts, will draw 2.3 Amps, so as long as your battery can handle 2.3 Amps, then you would not be surpassing the limitations of the battery. the "safe" distance is really a personal decision. Batteries are rated for continuous and burst, the burst is usually close to double the rating of the continuous. Alot of people try to go a certain % under the continuous rating and they feel safe, Ive personally gone sligtly over the continuous rating on one of my 18350 batteries because I am still under the burst rating and am careful with how long I hold the button for (but of course I would never encourage anybody to surpass the limitation of their batteries, I am just sharing my personal experience). So if you do not feel comfortable getting too close to the battery's continuous amp rating, then dont. You can certainly achieve a more than satisfying vape experience without dropping to really low ohms. hell you might not even enjoy a .2 ohm build anyways.
So anyways, what is considered a "safe" distance of the max
AMPERAGE of a setup is subjective as long as you are not surpassing the limit. Naturally, the farther away from the limit you are, the "safer" it is.
