Now this is very concerning. Those are in fact the batteries that came with the kit, and if they are dangerous, then why would Sigelei put them in their kit and risk a law suit? Not that I haven't heard that this is possible before with other mods, but damn...now I am a little worried. Are there any precursors I should watch for before they fail? I've heard that you can stack batteries as you've done, and have it be ok, but it is still relatively unsafe (or rather less safe than using one 18650). I've already spent my vape budget for this month, but damn....now I'm more confused than ever which batteries to get and whether or not I can wait until February to do so. Right now, the zmax is what I am using exclusively...
I'm also very interested in your battery comparison, fairmana.
That website I linked in my post could have incorrect information. I'm not sure how reliable it is, but either way, I've since stopped using the Sigelei batteries and moved on to the Panasonics with discharge limits beyond what the Zmax is capable of allowing through its circuitry.
I should have mentioned in my previous post that while I stack 18350s to achieve 15w on a dual coil Igo-s, doing so can be dangerous. IMR batteries should be used and voltages should always be tested using a voltmeter before stacking the batteries in the Zmax.
If you are on the lookout, I would recommend the Panasonics. I picked up two of them for $19.99, but I am sure there are better prices online. I also have some Efest 18650 IMR 2000 mah batteries on the way that I'll use with my Nemesis clone, when that arrives as well.