If you want to buy a hybrid automobile from luxury manufacturer Infiniti today, your only option is the performance-oriented M35h.

The big sedan can reel off a 0-60 mph time of 5.2 seconds (on par with the range-topping M56), yet it's still rated at 27 mpg around town and 32 mpg on the highway. While those are impressive numbers, the M35h isn’t the right choice for every buyer.

To expand its hybrid product range, Infiniti is looking beyond the M35h’s normally-aspirated 3.5-liter V-6 and electric motor combination toward a new powertrain for an upcoming JX Hybrid crossover.

Its goal is a setup that will provide a bit less thrust and a bit more fuel economy, which it demonstrated at a Nissan Advanced Technical Briefing held today at the company's GranDrive facility in Oppama, Japan.

The company let journalists drive a prototype Infiniti JX crossover fitted with a supercharged 2.5-liter four-cylinder engine, paired with the same 50-kilowatt (67-hp) electric motor as in the M35h, but driving through the company's new continuously variable transmission (CVT) for larger vehicles.

While executives wouldn't confirm that an Infiniti JX Hybrid is imminent, it's a foregone conclusion given that journalists were asked for their input on the car.

The drivetrain can easily be adapted to mechanical all-wheel drive via a takeoff designed into the new CVT, Nissan engineers pointed out--unlike the optional all-wheel drive system in the competing Lexus RX 450h, which uses an electric motor to power the rear axle.

The new Infiniti hybrid system could also be built as a plug-in hybrid, to give Infiniti another plug-in car along with its upcoming LE all-electric sedan.

As the system is still under development, Nissan didn’t provide numbers on combined output or fuel economy.

But the JX Hybrid prototype produced plenty of thrust, and development engineers said the fuel economy was expected to run about 20 percent higher than the 3.5-liter V-6 and CVT combination fitted to the current 2013 Infiniti JX that went on sale earlier this year.

One potential drawback may be the JX Hybrid prototype's almost complete lack of all-electric running. It proved impossible to accelerate at any speed without the engine switching on, whereas the RX 450h hybrid can move itself around town, under light loads, electrically.

Questioned about this, Infiniti engineers said that M35h owners valued its "electric gliding" at freeway speeds, when the engine switches off under light loads and the electric motor propels the car until load increases.

Assuming the Infiniti JX Hybrid reaches the market, the question will become: What do suburban moms--whose friends may already drive an RX hybrid--expect from a hybrid crossover? Is it simply higher fuel economy, or does it also include some degree of electric running?

Since it’s been designed for front- and all-wheel drive applications, it’s unlikely the JX Hybrid drivetrain will appear in the upcoming G35h (rumored to be among the next-generation G sedans).

Until we hear otherwise, our best guess still has that car getting a detuned version of the M35h’s hybrid drivetrain.

Nissan provided airfare, lodging, and meals to enable High Gear Media to bring you this first-hand report.