First off, yes I smoke cigarettes. Second, I don’t care how you feel about it because I don’t litter the streets with my butts, and I smoke outside. I’m just wondering if the PriusV 12v plug can handle the heat from a cigarette lighter. Or will it melt?
Some are 15 amp and others are 10 amp rating. To be safe, you could check the fuse panel under the hood and see what the fuse is rated for. You didn't state the current draw of your cigarette lighter. My friend has a new Nissan Altima and he said that they changed the design of the socket. He bought a cigarette lighter and tried it but it wouldn't work in his car.
An actual cigarette lighter socket always has a metal barrel and a bimetal clip at the bottom that holds the lighter in when you press it in, but releases it when it gets hot. You could buy one from autozone, amazon, etc., and install it in your car. https://www.amazon.com/EKYLIN-Cigarette-Lighter-Replacement-Assembly/dp/B06ZZ69B6C