LOS ANGELES—Fiat Chrysler Automobiles NV is putting on sale a battery-powered version of its popular minivan and is struggling with a problem many car companies confront when wading into the electric-vehicle market with a car that has complicated technology: What do you call it?

The new version of the Chrysler Pacifica is a highlight of this month’s Los Angeles Auto Show and is hitting dealerships. Customers have two ways of fueling the minivan, with a conventional gasoline-filling equipment in the back and a port for plugging...