Hyundai Sonata

Hyundai officially announced plans yesterday to produce a hybrid version of the Sonata sedan in 2010. It will be the automaker’s first production version gas-electric hybrid in the United States. The company previously made noises about entering the hybrid market with subcompact hybrids, but Hyundai’s hybrid plans were indefinitely delayed before getting very far along. The company seems to be back on track: The Sonata Hybrid will make its world debut at the 2008 Los Angeles International Auto Show in November.

Though most details about the Sonata Hybrid are being kept under wraps, a Hyundai executive revealed yesterday that the vehicle will utilize lithium ion batteries, as reported by Associated Press. Lithium technology holds great promise for boosting the efficiency of hybrids. But for most consumers, the choice of battery chemistry is a purely technical matter. The more important and most critical question is, “What’s the mpg?”

Car shoppers will have to wait some time before getting a definitive answer. spoke with a Hyundai spokesperson, who asked not to be named. “Fuel economy should be improved by 20 to 25 percent, but those are not hard numbers,” he said. “We’ll talk more about that when the car is introduced in LA.”

The current Sonata midsize sedan grants 22 mpg in the city and 32 on the highway. Do the math, and it means that the Hybrid Sonata could achieve combined fuel economy better than 30 miles a gallon. By comparison, the Camry Hybrid beats out the four-cylinder conventional Camry by the same 20 to 25 percent, while the Chevrolet Malibu Hybrid manages about a 9 percent gain over its gas-powered counterpart.

Hyundai’s decision to enter the hybrid market comes after a record-high spike in gas prices. Noboby knows where fuel prices will be in two years, when the Hyundai Sonata Hybrid goes on sale, but the Sonata Hybrid could match the fuel economy ratings of the most efficient family sedans on the market—for thousands of dollars below the competition. Pricing and many other specs are not yet available. While the standard Sonata is built in Alabama, the production site for the upcoming hybrid is also unknown.