Hyundai Unveils the 2011 Sonata Hybrid (Lithium-Polymer Batteries, 37/39 MPG)

hyundai sonata hybrid photo

Photo: Hyundai
Finally Some New Blood
Hyundai is challenging Toyota and Ford in the mid-size hybrid segment with the new Sonata hybrid which was unveiled today in New York. And at least on paper, it is quite competitive! It gets a slightly different styling from the regular 2011 Sonata (probably because of Toyota's experience with the Prius -- fewer people buy hybrids that look exactly the same as their non-hybrid counterparts), but the really interesting part is what's under the hood. Read on for the technical specifications.
hyundai sonata hybrid photo

Photo: Hyundai
Under the Hood of the Sonata Hybrid
Hyundai calls its hybrid system "Blue Drive". For the Sonata, it means combining the 2.4-liter Theta II gas engine (running on the Atkinson Cycle), which produces 169 hp at 6,000 RPM and 156 lb-ft of torque at 4,500 RPM, with a a 30 kW electric motor (151 lb-ft of torque) via a 6-speed automatic transmission.

At 0.25, the Sonata hybrid's coefficient of drag is the same as on the 2010 Prius.

The transmission choice is interesting; the Toyota Camry hybrid, Nissan Altima hybrid and Ford Fusion hybrid all use a CVT.

hyundai blue drive hybrid tech image

Photo: Hyundai
Battery Pack
The other thing that sets the Sonata hybrid apart from the competition is its battery chemistry. While all the others use nickel-metal hydrides (NiMH), the Sonata goes for a more energy-dense lithium-polymer battery pack made by South-Korea's LG Chem.

Compared with nickel-metal hydride batteries, lithium polymer batteries deliver the same power with 20-30 percent less weight, 40 percent less volume and 10 percent greater efficiency over the nickel-metal hydride batteries found in today's hybrids. Lithium polymer batteries offer 1.7 times more energy density than nickel-metal hydride batteries, allowing Hyundai engineers to devote less space and weight to the battery pack. Lithium polymer batteries hold their charge 1.25 times longer. Lithium polymer batteries also are more resistant to changes in temperature, which improves cycle life. Additionally, lithium polymer's self-discharge rate is less than a third of a nickel-metal hydride battery.

Fuel Economy
At 37 MPG in the city and 39 MPg on the highway, projected fuel economy is close to the Fusion hybrid (41/36 MPG), and which will do best will depend on whether it is used mostly in the city or on the highway.

Pricing and Availability
Hyundai says that the 2011 Sonata hybrid will be in showrooms "later this year", but no word yet on price.

See also: The 2011 MKZ is Lincoln's First Hybrid (41 MPG City Projected)

Via Hyundai
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