The Mitsubishi Outlander PHEV has been a huge success in Europe, selling more than 100,000 copies there over several years.

As the first and least expensive plug-in hybrid SUV, it received many incentives in different European countries and provided the first taste of plug-in electric driving for numerous families.

Now, the plug-in hybrid Outlander is getting some updates for the 2019 model year, arriving in those markets toward the end of this year.

DON'T MISS: 2018 Mitsubishi Outlander PHEV: first drive of plug-in hybrid SUV

The updated Outlander PHEV will debut at the Geneva auto show early next month, accompanied by the first European showing of the Mitsubishi e-Evolution concept for an all-electric SUV that premiered last fall at the Tokyo auto show.

According to a press release earlier this week, the European 2019 Outlander PHEV will feature a new and updated generation of the vehicle's plug-in hybrid powertrain.

The previous 2.0-liter inline-4 engine, operating on the conventional Otto Cycle, has been replaced by a larger one of 2.4-liter capacity specially tuned to run on the ultra-efficient Atkinson Cycle instead.

2018 Mitsubishi Outlander PHEV, Catalina Island, CA, Sep 2017

2018 Mitsubishi Outlander PHEV, Catalina Island, CA, Sep 2017

Mitsubishi said the new engine provides " higher torque, smoother operation, and overall higher efficiency," though it gave no new projections for fuel economy or energy efficiency.

The 2018 Outlander PHEV is EPA-rated at 22 miles of electric range, 25 mpg combined when running as a hybrid, and 74 MPGe in electric mode.

Miles Per Gallon Efficiency, or MPGe, is a measure of how far a vehicle can travel electrically on the amount of energy contained in 1 gallon of gasoline.

READ THIS: Mitsubishi e-Evolution Concept electric SUV for Tokyo Motor Show

In addition, Mitsubishi said, the rated outputs of both the generator and the rear drive motor are 10 percent higher.

And, it said, the energy capacity of its battery pack will grow by 15 percent—which would boost it from 12 kilowatt-hours to 13.2 kwh—and its power output will increase by 10 percent as well.

The company has also added Sport and Snow modes to the 4WD system's current pair of modes: Normal and 4WD Lock.

2018 Mitsubishi Outlander PHEV, Catalina Island, CA, Sep 2017

2018 Mitsubishi Outlander PHEV, Catalina Island, CA, Sep 2017

2018 Mitsubishi Outlander PHEV, Catalina Island, CA, Sep 2017

2018 Mitsubishi Outlander PHEV, Catalina Island, CA, Sep 2017

2018 Mitsubishi Outlander PHEV, Catalina Island, CA, Sep 2017

2018 Mitsubishi Outlander PHEV, Catalina Island, CA, Sep 2017

Exterior changes to the plug-in Outlander include updates to the grille, a front skid plate, a larger rear spoiler, and new LED headlights, as well as a "more elaborate" two-tone design for the 18-inch alloy wheels.

Inside the cabin, updates include new and more heavily bolstered front seats, a new instrument panel and changes to switches and knobs, available quilted leather upholstery, and rear-compartment ventilation outlets.

The result, Mitsubishi said, is a 2019 Outlander PHEV with "sharper dynamics, a more refined interior, and a subtle design evolution."

CHECK OUT: 2018 Mitsubishi Outlander PHEV starts at aggressive price of $35,500

Whether these updates will appear on the U.S. versions of the plug-in crossover utility vehicle remains to be seen, but we've reached out to the company's U.S. arm for comments.

We'll update this story if we get any response.

For all the latest about green-car concepts and production models on display in Switzerland, see our Geneva auto-show news page.

EDITOR'S NOTE: An earlier version of this article transposed the two engine sizes. The existing Otto Cycle engine is 2.0 liters, and the upcoming Atkinson Cycle engine is 2.4 liters, not the other way around. We apologize for the error.