Hyundai unveiled its mainline Sonata midsize sedan in two notable new editions at the recent 2010 New York International Auto Show—a significant hybrid version and a powerful twin-turbo model.
The Korean company claimed that the 2011 Sonata Hybrid delivers more total power—209 hp (156 kW)—than any midsize hybrid as well as class-topping fuel economy thanks to a lightweight structure, a proprietary parallel-hybrid drivetrain, and new lithium-polymer pouch batteries—an auto industry first.
The thrifty new sedan, which weighs in at 3457 lb (1568 kg), a couple hundred pounds less than the Ford Fusion Hybrid, gets an estimated EPA rating of 39 mpg on the highway and a good 37 mpg on city streets, said Hyundai Product Planner Michael Dietz.
Power derives from the combination of a 30-kW, 151-lb·ft (205 N·m) electric motor and a 2.4-L Theta II direct-injection inline four-cylinder engine that develops 169 hp (126 kW) at 6000 rpm and 156 lb·ft (212 N·m) at 4500 rpm. Dietz said that the high-efficiency Atkinson-cycle powerplant benefits from continuously variable valve timing and a low-friction oil pump.
The full parallel-hybrid Blue Drive, including gasoline engine, electric motor, starter-generator, and a new six-speed automatic transmission, eliminates the need for the planetary-gear torque-converters used by competing CVT-equipped hybrids. Regenerative brakes, start/stop technology, and an electric HVAC compressor complete the package. Dietz also pointed out a lower front grille air shutter that closes at higher speeds to smooth aerodynamics and opens at lower speeds to optimize engine-cooling airflow.
The Sonata’s full parallel architecture, in which the wheels get power from the internal-combustion engine, the electric motor, or both as conditions require, provides significant efficiency benefits at higher speeds, Dietz said. The new hybrid can travel at 62 mph (100 km/h) on electric power alone in part because it uses lithium-polymer batteries made by Korea’s LG Chem, which he explained are smaller, lighter, more durable, and more resistant to temperature change than conventional nickel/metal-hydride and the newer lithium-ion batteries.
“The Sonata’s lithium-polymer battery pack weighs 28 pounds less than the nickel/metal-hydride one in the Toyota Camry,” Dietz noted. The Sonata marks the automotive debut for the pouch-type cells, which are distinguished by their use of a polymer gel as the electrolyte.
The Sonata’s “full parallel-hybrid configuration and breakthrough lithium-polymer batteries offer a new take on traditional hybrid design, while its unique technology sets it apart from the midsize hybrid pack,” said John Krafcik, Hyundai Motor America CEO.
Also revealed at the Javitz Center was a new high-performance version of the Sonata in Turbo form. Hyundai’s midsize hot-rod is fitted with a twin-scroll turbocharged 2.0-L Theta II GDI engine that generates a noteworthy 274 hp (204 kW) and 269 ft·lb (365 N·m) but still gets 22 mpg in the city, 34 mpg on the highway.
The estimated EPA highway number is only one tick below that of the standard Sonata’s, and the turbo engine runs on regular 87-octane unleaded gas. “Think about it,” Krafcik said, “more horsepower than any of our V6 competitors, with better gas mileage than any competitive four-cylinder model.”