Just when it seemed like everybody was betting the farm on battery-electric cars, along comes Mercedes-Benzwith a fuel-cell SUV. The GLC F-Cell, which debuted Tuesday at the Frankfurt Motor Show, illustrates that Mercedes' parent Daimler is already planning for the day when straight BEVs aren't enough and potentially fuel-cell cars become vital. It's the follow-up to the 2010 B-Class F-Cell.

The GLC F-Cell should be ahead of the curve, falling under Daimler's EQ electric-car brand with about 10 pounds of hydrogen stored in two tanks, delivering 272 miles of zero-emission range. It should still move around to act like a normal GLC pretty well, because its electric motor delivers 197 horsepower and 258 pound-feet of torque — the instant kind. The use of fuel-cell technology means the GLC F-Cell's batteries don't need to be as large, expensive or heavy as in a pure BEV, so it uses only a 13.8-kWh lithium-ion battery pack.

While that delivers 30 miles of pure BEV driving on the NEDC test, the rest of the GLC F-Cell's range comes directly from its hydrogen fuel cell acting as an on-board power station. It generates electricity on its own to directly drive the electric motor or to recharge the lithium-ion battery packs, emitting nothing but water vapor.

It's also technically a plug-in hybrid fuel cell/BEV, because the lithium-ion battery can be recharged from either a wall socket or a charging station to deliver more battery range. Its official fuel consumption figure is about a 40 percent step forward from the B-Class F-Cell, while the fuel-cell system is about 30 percent smaller. It's so much smaller that instead of forcing a complete re-engineering job on the underbody to house the tanks, the entire system is now housed inside the standard GLC engine bay. It even uses the standard engine-mount brackets.

Even with an asynchronous electric motor directly driving the front wheels, the GLC F-Cell can fit one of its hydrogen tanks in the engine bay, while the second sits beneath the rear seat. Another big step forward has been a 90 percent reduction in the amount of platinum Mercedes-Benz needs in its fuel cell, which lowers its production costs enormously.

"Our many years of experience with fuel-cell technology pay dividends in the new GLC F-CELL: Its long electric range, short refuelling times and everyday practicality of an SUV will make it the perfect vehicle," Daimler's board member for research and development, Ola Kallenius, said.

It falls within the EQ brand's remit, largely because it's been the product of tapping into the pooled resources of its electrification group inside Kallenius's own development branch, though Daimler now has more than 11 million miles worth of fuel-cell data.

With another 10 pure BEVs planned to launch before 2022, Daimler hopes that defining the GLC F-Cell as a plug-in hybrid will convince people it's a family-friendly practical car. Acknowledging that finding hydrogen isn't always easy for city dwellers, it will recharge its lithium-ion battery in about 1.5 hours from a 7.2-kW on-board charger. Its hydrogen tanks use the standard 700-bar pressure and are encased in carbon-fiber. Built into the GLC's floor, they can be fully refueled in only three minutes — about the same time as a conventional gasoline or diesel-powered car.

The fuel-cell stacks were developed in Vancouver, Canada, as part of Daimler's joint venture with Ford, while the fuel-cell unit and its hydrogen storage setup were developed by NuCellSys, Daimler's subsidiary company in Baden-Wurttemberg and its Accumotive battery subsidiary developed and assembled the lithium-ion battery. It has a range of driving modes, too, with its hybrid mode combining both the lithium-ion battery's stored energy and the fuel cell's real-time delivery to power the car.

A dedicated F-Cell mode keeps the battery's charge high and runs the car on its fuel cell almost entirely, while the Battery mode does the opposite and runs as a pure BEV. There's a Sport mode for faster driving and a Charge mode that uses all of its regenerative braking capacity and its fuel cell to recharge the lithium-ion battery.

The SUV's cabin is largely untouched, though it has a step-up in the luggage area that isn't there on the internal-combustion models and the rear seat is slightly higher so it can swallow the second hydrogen tank.

The car will ride on a standard package of a coil-spring front suspension setup and a single-chamber air suspension at the rear, and 20-inch wheels and tires. Inside, the GLC F-Cell will debut Benz's new multifunction touchpad, which recognizes most of the world's handwriting styles.

Built in Bremen alongside the conventional GLC, the F-Cell is already filling Benz's test fleets and the company plans to put it into rental fleets to acclimate people to the technology. Germany is slated to have 100 H2refuelling stations by the end of the year and 300 more by the end of 2023.