Well, that's the general idea, all right. But with a mech mod, remember the only safety device is between your ears; it has no circuitry to protect you. Because it has none, you must watch out for your own safety by knowing you are not overloading your batteries. There is a mathematical relationship between the coil resistance value and the amp draw on the batteries, but this is less involved for you since you will not be building coils but rather buying them at fixed resistances. The long and the short of it is, with a .7Ω coil at full battery charge, you will be loading your battery to 6A discharge current.
I strongly recommend you buy a couple AW 18490 batteries from rtdvapor.com (
AW IMR 18490 3.7v 1200mAh )-- the website at HoH says the Nabuki takes flat or button top batteries and recommends AW brand, which is a good one. RTD is a reputable vendor, and you'll get what you pay for. The battery I linked is rated at 15C by the manufacturer, which means a discharge rating of 16 amps or so; well above the 6 amps your rig will draw. I am sure that will be quite safe. I am a bit concerned if you use an off-brand battery you could get something not rated for vape usage with unpleasant results.
You know you need a stand alone battery charger as well, yes? There is no way to plug in a mech mod and charge within the mod itself. Xtar and Nitecore are good brands. I'd recommend at least a two-bay charger, and get a 4-bay if the budget will stretch, even if you only buy two batteries. You may have more (batteries and/or mods) in the future. I use both brands, but I personally like the Nitecore D4 best of all. Chargers can be safely bought on eBay from top rated sellers, but buy your batteries only from a good retailer. You can ask here whom they are, or Mooch has a chart naming some good ones.