Hybrid Blue Drive is made up of nine major components:

1. Optimized Theta II 2.4-liter engine;
2. Integrated starter generator for stop-start;
3. 30 kW electric motor delivering 205 Nm of torque;
4. Regenerative braking system;
5. 6-speed automatic transmission with an improved efficiency electric oil pump;
6. 1.4 kWh lithium polymer battery pack (5.3 Ah, 270 V);
7. Hybrid power control unit;
8. Electric air conditioning compressor; and
9. Weight-efficient architecture coupled with a low drag coefficient.

To maximize fuel economy, all of the Theta II major driveline and cooling system components have been optimized to reduce friction, while the crankcase has been filled with low-friction oil. Engine management software automatically shuts off the engine when the vehicle comes to a halt, cutting emissions to zero. When pressure is reapplied to the accelerator pedal, the Integrated Starter Generator (ISG) automatically restarts the engine.

The Theta II’s engine management software governing injection pressure, engine cycle timing and exhaust treatment rates has been revised to further reduce fuel consumption. This control strategy assures that maximum efficiency is achieved during gentle acceleration and greater power is immediately available during full acceleration. During deceleration, braking regeneration comes into play.

In addition, the top three gear ratios in the transmission have been extended to ensure the engine runs at lower RPMs, the latest electric motor-assisted steering system reduces power drain and low resistance tires further optimize fuel economy.

Benefits of the lithium polymer technology. Click to enlarge.

Hyundai is emphasizing the benefits of LG Chem’s lithium polymer technology. LG Chem is currently using a manganese-spinel based cathode with amorphous carbon anode; its proprietary Safety Reinforcing Separator (SRS); and a polymer gel electrolyte of LiPF₆ in organic salts all in a laminated package.

The SRS uses nanoscale ceramic particles to prevent internal short circuits. The separator offers excellent abuse tolerance due to its thermal and mechanical strength.

With the Mn-based cathode, LG Chem has achieved more than 15 years of calendar life and 150,000 miles of cycle life with excellent abuse tolerance. Hybrid Blue Drive is targeting maintenance-free battery operation over the vehicle’s life—at least 10 years, and 150,000 miles—in all weather conditions.

Compared with today’s NiMH batteries deployed in hybrids, the LG Chem lithium polymer batteries deliver the same power with 30% less weight, 50% less volume and 10% greater efficiency.

The lithium polymer batteries offer more than twice the energy density of NiMH cells, and 175% greater volumetric energy density, meaning Hyundai engineers can devote less space and weight to the battery pack.

Other aspects of Blue Drive

The Blue Drive initiative also incorporates non-hybrid technologies for fuel efficiency, including turbocharged gasoline direct injection engines, improved aerodynamics and weight reduction, and fuel cells.

The 2.0-liter Theta turbocharged GDI engine. Click to enlarge.

Turbocharged GDI. At the earlier Geneva International Motor Show, Hyundai introduced the HED-5 i-Mode concept car. At the Los Angeles show, Hyundai Motor America announced that a production version of this compact, four-cylinder crossover has been green-lighted for the US, with timing to be announced at a later date.

The HED-5 concept shown in Los Angeles used an advanced 2.0-liter Theta turbocharged gasoline direct injection (GDI) four-cylinder engine capable of developing as much as 286 hp (213 kW) while and delivering more than 30 highway mpg. This engine will appear in various Hyundai models in the future.

Four-cylinder turbocharged gasoline direction injection engines can be 15-20% more fuel efficient than V6 engines without compromising performance, Hyundai said.

Blue editions. Next year, Hyundai will introduce high mileage Blue editions of its Accent and Elantra models. Fuel-efficient modifications include low-rolling-resistance tires, enhanced aerodynamics, revised engine calibrations and reduced final drive ratios to deliver higher mileage and lower emissions than today’s models. These new high mileage editions will be identified with Blue badging.

Fuel cell vehicles. Hyundai said that the ultimate expression of Blue Drive is the hydrogen-powered Fuel Cell Electric Vehicle. Hyundai is participating in fuel cell verification programs around the world.

In the US, Hyundai has been a member of the California Fuel Cell Partnership (CaFCP) since 2000. In 2004, Hyundai began a partnership with Chevron Corp. and UTC Power to initiate a 32-vehicle fleet testing program. This five-year cost-sharing program is sponsored by the United States Department of Energy.

Hyundai recently completed a 13-day, cross-country road trip that served as the first significant US test for its proprietary fuel cell technology. The Tucson Fuel Cell Electric Vehicle (FCEV) on display in the Hyundai booth completed a 4,300 mile journey as part of the Hydrogen Road Tour 2008.

Hyundai said that it is targeting putting a Hyundai Blue Drive Hydrogen Fuel Cell Electric Vehicle in series production as early as 2012.