Hyundai Sonata Hybrid - new high mileage Hybrid system

Achieving some of the best highway fuel economy yet for a hybrid, the all-new Hyundai Sonata Hybrid pioneers several technologies with its Direct Hybrid Blue Drive system. "It's all about the fuel economy, stupid," is driving Hyundai engineers to keep the brand at the top of the U.S. Corporate Average Fuel Economy (CAFE) rankings. The 2011 Sonata Hybrid is simply another step forward in a strategy aimed at a corporate 50 mpg CAFE by 2025.

In planning the Sonata Hybrid, a conscious decision was made to trade off the highest EPA-estimated city mpg possible for a uber-high highway number, according to Hyundai's director of product planning Scott Margason. He said that because Hyundai determined that the majority of miles driven are highway miles -- 58 percent by their findings -- they concentrated on maximizing Sonata Hybrid's highway fuel efficiency as the avenue for the highest overall fuel economy.

That's not to say the Sonata Hybrid's city mpg isn't among the best in the midsize hybrid segment, at 36 mpg it clearly is; but the 40 mpg EPA-estimated highway rating leads the bulk of the midsize pack. Only the Toyota Prius, engineered from the ground up as a hybrid, racks up better EPA ratings in the midsize segment: 51 mpg city/48 mpg highway.

Also separating the Sonata Hybrid from its direct competitors is the versatility of its hybrid system. A fully parallel system, Direct Hybrid Blue Drive allows Sonata to be driven at speeds up to 62 miles per hour in electric-only mode. As with other hybrid technology, recharging the batteries is achieved through such schemes as capturing energy from braking and generating energy from the gasoline engine.

While other hybrid systems have traditionally relied on nickel metal hydride batteries to run the electric motor, Hyundai's proprietary Blue Drive is the first to employ a lithium polymer battery array developed in conjunction with LG. Basically lithium polymer batteries provide better energy density and thermal stability than either nickel metal hydride or lithium ion batteries, making them more efficient and durable. Hyundai claims lithium polymer batteries hold a charge 25 percent longer, so there is more electric power available for propelling the car. Another benefit is a smaller, lighter battery pack.

Delivering 166 horsepower, the gasoline-engine is a 2.4-liter four-cylinder. Combining it with the 30kW electric motor delivers a total of 206 horsepower and 193 pound feet of torque. The bulk of that torque -- 151 pound feet -- is generated by the electric motor and is instantly available. Acceleration is enthusiastic and satisfying.

Typically some interpretation of a continuously variable transmission (CVT) transfers engine and motor output to a hybrid's wheels. Hyundai once again breaks with tradition by using a conventional six-speed automatic transmission used in other Sonatas to usher power to the pavement. Because a conventional transmission is less expensive than a CVT, its use in the Sonata Hybrid will help Hyundai keep the suggested retail price affordable when it is finally announced later this fall.

In terms of handling and steering, the Hybrid behaves very much like the entry-level GLS. The four-wheel independent suspension with its MacPherson struts up front and multi-link arrangement in the rear is tuned much like the GLS underpinnings. That is to say, the emphasis is on a pliant ride and passenger comfort. Yet it enters and exits curves at speed without drama. The steering is light, but responsive. Also like the GLS, the Hybrid rides on 16-inch alloy wheels and rubber. Seventeen-inch ones are an option.
All Sonatas get equal treatment in the safety department. All four wheels cover disc brakes controlled by an antilock system. Electronic stability control, traction control, electronic brake-force distribution and emergency brake assist are all standard. Inside six airbags and active front head restraints contribute to keep occupants safe in a crash.

Hyundai completely redesigned Sonata for 2011. The Hybrid features the same chiseled, buffed exterior and comfortable, stylized cabin as the gasoline-only versions. Arguably it is the most handsome exterior among midsize competitors that include the Toyota Camry, Honda Accord, Nissan Altima, Chevrolet Malibu and Ford Fusion among others. Its head-turning good looks have nothing to do with the fuel economy of the Hybrid's Blue Drive. Only some badging differences set it apart from other Sonatas.


Likewise the interior pretty much mirrors the innards of other Sonatas. There are some hybrid-only graphics that can be displayed on the center-stack-mounted monitor or the in the main-gauge pod, but the basic interior architecture is the same within the Sonata lineup. Again the cabin feels a lot like the GLS in terms of materials and surfaces.

Comfortable seats and gobs of front- and rear-seat legroom make for a homey environment. Controls for the six-speaker audio system with CD player, iPod/USB input jacks and satellite radio capability, as well as the dual-zone automatic climate control are easy to find and use. Other standard features include full power accessories, eight-way power driver's seat, keyless entry and start, tilt and telescoping steering wheel with redundant audio controls, Bluetooth cell phone connectivity, folding/heated outboard mirrors with turn-signal indicators, and trip computer.

Hyundai won't announce pricing for the Sonata Hybrid until just before it arrives in dealer showrooms in November, but expect a base price below $25,000. Additionally, it won't commit to its warranty terms for the battery array until it announces pricing. Stay tuned.