I vaped rca123s for 6v in my Red Diamond mod for a while but it wasn't very smart. Some mods are made have stacked batteries like the Akston Hughes models. Just don't be the guy who blows his teeth out so that I don't have to hear, "Did you hear about that guy who blew his teeth out with those things". Then I have to go into a long winded explanation about stacked batteries and protected vs. unprotected, etc.
Oh, and I'm concerned for your safety. Happy vaping!
Yeah, but the mods made with stacked batteries are all VV and regulating the voltage down instead of boosting it up. Those stacked battery mods are nothing really to worry about. The Ovale V8, Vmax, Vari-Volt and a few others use stacked batteries as well. It's actually a more efficient and powerful way to get to the higher voltage. The internal circuits prevent the kind of disaster that blows the connector through your neck.