Hyundai Sonata Hybrid

Hyundai Sonata Hybrid

 

The Hyundai Sonata Hybrid, expected to hit dealerships later this year, is the South Korean company’s first hybrid in the US market. Apparently, Hyundai took its time, scrutinized the hybrid competition, and attempted to outdo it in every respect. At a price below $26,000, Hyundai has produced a mainstream mid-size hybrid sedan that provides real competition for class-leading fuel economy. Hyundai expects the Sonata Hybrid to achieve 37 miles per gallon in the city and 39 mpg on the highway.

The company is taking direct aim at the Toyota Camry Hybrid (33/34) and Ford Fusion Hybrid (41/36), the two most popular regular-looking mid-size hybrid sedans. While the Hyundai Sonata Hybrid does not look exactly like its conventional sibling—more about that in a moment—Hyundai decided not to copy the unique aero-look of the Toyota Prius and Honda Insight. Moreover, Hyundai went its own direction on technology—by developing an original proprietary hybrid architecture to reduce weight and to improve highway fuel economy.

"The Hyundai Sonata Hybrid is the new kid on the block, but it's not a follower," said John Krafcik, president and CEO, Hyundai Motor America. "Its full parallel hybrid configuration and breakthrough lithium polymer batteries offer a new take on traditional hybrid design, while its unique design sets it apart from the mid-size hybrid pack."

Balancing Highway and City MPG

Unlike hybrid systems from Ford and Toyota, the Hyundai system does not use a continuously variable transmission with integrated electric motors and generators. Instead Hyundai is using its new six-speed automatic transmission with an electric motor that takes the place of the torque converter. The Sonata Hybrid's six-speed automatic transmission could be its powerful secret weapon. What’s the difference? It means that Hyundai is trying to address the common complaint that hybrids are boring to drive—and provide great mileage for city driving conditions, but not so much for highway driving. 

“Unlike traditional [power-split] hybrids that trade off highway fuel economy for higher city ratings, the Sonata Hybrid delivers best-in-class highway fuel economy, while still delivering about a 40 percent improvement in city fuel economy compared to a Sonata equipped with the Theta II GDI engine,” said Krafcik. “We think this is a better balanced approach for the majority of car buyers.”

The full hybrid architecture allows the vehicle to operate on an electric motor only, a gasoline internal combustion engine only, or a combination of the two depending on driving conditions and driver demands. The approach also results in a total combined output of the engine and motor of 209 horsepower—beating out the Camry Hybrid (187 hp) and the Ford Fusion Hybrid (191 hp).

The hatchback Toyota Prius, with its combined 50-mpg rating, is still way ahead of the pack on both highway and city efficiency numbers—but shoppers are more likely to put the Sonata Hybrid in the larger mid-size sedan (with trunk) category along with the Camry and Fusion.

Lithium Polymer Batteries and Lighter Weight

Hybrid critics have complained that the need to tote heavy batteries means one step forward and two steps back. Hyundai deals with that issue by using lightweight lithium polymer batteries. The lighter batteries, and other weight reductions make the Sonata Hybrid the lightest vehicle in the segment, at just 3,457 pounds—263 pounds lighter than the Fusion Hybrid. Combined with Sonata’s best-in-class horsepower rating, Sonata Hybrid has a significant advantage in power-to-weight ratio.

The Sonata Hybrid’s 1.4 kilowatt-hour pack battery pack weighs just 95.9 pounds versus the Camry Hybrid’s 123.9 pounds. The compact battery pack resides in the forward portion of the trunk to maximize cargo space. Compared with nickel metal hydride batteries, lithium polymer batteries deliver the same power with 20 to 30 percent less weight, 40 percent less volume and 10 percent greater efficiency over the nickel metal hydride batteries found in today’s hybrids. The battery cells, supplied by LG Chem, are similar to the cells that General Motors are using in the Chevrolet Volt.

Slick and Slippery

If Hyundai can undercut the price of the Fusion and Camry hybrids, it will deliver a more powerful and efficient vehicle at a better value. But what does it look like? On that front, Hyundai puts form in service of function—better aerodynamics. The most dramatic design flair is an all-new front fascia, with anthropomorphic lizard-eye headlights. New wheels and extended rocker panels improve airflow across the flanks. In the back, the bumper cover has been reshaped with sharp creases at the corners to minimize drag. These changes drops the hybrid's projected drag coefficient from the standard Sonata's already slippery 0.28 to just 0.25—matching the 2010 Toyota Prius’s drag coefficient.

Keep your eye on the new kid on the hybrid block.