While Toyota remains coy about the launch date of its fourth-generation Prius hybrid, a company executive has confirmed that the car is coming "soon."

Jim Lentz, CEO of Toyota North America, didn't release any specifications on the car when he mentioned it during the groundbreaking for an expansion of the Toyota Technical Center near Ann Arbor, Michigan.

Industry sources expect the car to be unveiled either at the Tokyo Motor Show in September or the Los Angeles Auto Show in November.

DON'T MISS: Is This The Next Toyota Prius Hybrid Captured On Video?

But Lentz did tell the Detroit Free Press that he'd driven the new model, and that it was "fantastic."

The all-new 2016 Toyota Prius will be notable in at least three ways, the company has suggested.

2015 Toyota Prius Liftback

2015 Toyota Prius Liftback

First, it is likely to offer at least a 10-percent improvement on the current model's combined EPA rating of 50 miles per gallon, according to August 2013 statements by Satoshi Ogiso, Toyota's chief engineer--and the man in charge of developing the next range of Prius models.

That would take its combined rating to 55 mpg. Lentz said, however, that reports of a 15-percent improvement in gas mileage were "too high."

ALSO SEE: 2016 Toyota Prius Was Delayed Due To Redesign For Sportier Style (Dec 2014)

Second, the new Prius will have a sportier character--both in its design and its handling.

Current Toyota CEO Akio Toyoda has charged his company with adding more flair and passion to every product it releases, and he has raced in the past.

2015 Toyota Prius Liftback

2015 Toyota Prius Liftback

To the usual Toyota virtues of reliability and predictability, then, the new Prius may actually be fun to drive.

Finally, the new 2016 Prius is the first of many coming models to be built on a new "architecture," or set of structural underpinnings, that will be used across millions of future Toyota vehicles to achieve economies of scale.

MORE: Toyota Prius Plug-In Production To End In June; New One Coming Next Year

The next Prius may also offer all-wheel drive in one or more models--a feature that's increasingly viewed as necessary by drivers in wintry areas.

And there will be another plug-in Prius as well, most likely with a higher electric range than the present model's 11 miles.

2012 Toyota Prius Plug-In Hybrid - production model

2012 Toyota Prius Plug-In Hybrid - production model

The present Prius Plug-In Hybrid model goes out of production this month, and the new one appears likely to lag the introduction of the conventional model by some months.

The new 2016 Toyota Prius will be the well-known five-door Liftback model, incidentally.

The two additional vehicles in what has become a four-car Prius family were launched two years after the 2010 Liftback, so the Prius C subcompact hatchback and the Prius V five-door wagon are likely to be replaced in 2018 or so.

_________________________________________________

Follow GreenCarReports on Facebook, Twitter, and Google+.