i'm using a regulated mod so I should be good with all the protection built in. i'm using the kanger subtank and the subox mod.
Just so you know, the mod will will protect itself but It has no idea if the battery is being stressed too hard or not. And a battery being stressed too hard will have a shortened life and, if stressed hard enough, can vent or worse.
You must still select a battery that can handle the current the mod draws without overheating. From a safety standpoint whats important is your batteries continuous amp rating.
For a regulated mod, in VW mode, you calculate the max current draw as Max Amps = Max Wattage / Min Battery Voltage.
Min battery voltage is usually calculated using 3.2 volts (this is the point your mod will no longer fire).
With the Kanger Subox Max Amps = 50 watts/3.2 volts = 15.625 Amps. A 20A CDR battery will allow you to operate safely through the whole range of wattage/voltage of your devise.