The evidence is mounting that Hyundai plans to be a major player in the hybrid market. The 2011 Hyundai Sonata Hybrid, which is expected to get better than 40 MPG on the highway, will hit dealerships later this year. And as we reported in April, the Korean carmaker has a dedicated hybrid in the works. The new hybrid-specific lithium-battery-powered model will have a unique name and design—and will attempt to beat the Toyota Prius in terms of fuel efficiency. The company firmly believes that a hybrid needs a specific “green” look in order to compete for customers.

Now, The Detroit Bureau is reporting that Hyundai is “planning a big assault on the growing global market for gasoline-electric vehicles,” including plug-in hybrids. Within a decade, Hyundai expects that hybrids will make up 20 percent of its total global sales volume. Hyundai expects the biggest markets for hybrids to be Europe and Japan. “We are spending a fortune on hybrid development,” said Hyun-Soon Lee, the automaker’s vice chairman.

However, don’t expect full electric cars from Hyundai, according to The Detroit Bureau. Woong-chul Yang, president of Hyundai’s R&D operation, contends that lithium batteries still are still too costly and do not offer adequate range. “We’d need seven times the level of performance at 20 times less price,” he said. Hyundai officials said that a plug-in hybrid that’s able to go all-electric for the typical commute is a likely direction for the company.

Hyundai is trying to reach new higher U.S. fuel efficiency standards—35.5 mpg average by 2016—one year ahead of the mandate deadline. Within about three years, Hyundai could go from having no hybrids in U.S. showrooms to a 40-mpg mid-size hybrid, a dedicated 50-mpg hybrid, and a plug-in hybrid that will run mostly from electricity.