An improved hybrid system thanks largely to an upgraded battery has yielded big benefits for the most fuel-efficient, and the only plug-in, version of Toyota’s latest Prius.

The 2017 Prius Prime, which debuted today at the 2016 New York Auto Show, takes over where last year’s Prius Plug-In left off, combining 22 miles of emissions-free, fully electric driving with the standard Prius’ gasoline engine able to boost range to an estimated 600 miles.

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Those heady figures are highlighted by what Toyota says will likely be a 120 mpge rating, i.e. the distance the car can travel electrically on the same amount of energy that's contained in 1 gallon of gasoline. That figure would represent the highest mpge rating for any plug-in hybrid currently on the road.

After its 22 mile electric range is exhausted, the Prime drives like any standard Prius and Toyota estimates its EPA mpg rating in this mode will be the same as the standard model’s 52 mpg combined.

Making this all possible is the new car’s 8.8-kilowatt-hour battery pack, which Toyota says can be charged in 5.5 hours using a household outlet. A 240-volt Level 2 charger cuts that time in half.

2017 Toyota Prius Prime

2017 Toyota Prius Prime

Uniquely, the Prius Prime represents the brand’s first foray into using a dual motor generator drive system that allows both the electric motor and the generator to supply power to the wheels.

Like the standard Prius, the Prime’s gas engine is a 1.8-liter Atkinson-cycle 4-cylinder mated to a planetary-type continuously-variable transmission.

Also shared with the standard Prius is the basic body, though the Prius Prime gets unique touches, especially at the rear. The vehicle also gains some extras inside.

An 11.6 HD tablet-style screen displays the available navigation and infotainment systems. Prime models also include a suite of exclusive apps that allow users to remotely manage vehicle charging, locate charging stations, and track and compare their friends’ “eco driving score” from a smartphone.

Toyota says that the 2017 Prius Prime will be headed to American showrooms this fall. Pricing will be announced closer to the model's on-sale date.

For more on the Toyota Prius, see the in-depth reviews over at The Car Connection. And for more from the New York Auto Show, head to our dedicated hub.


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