Fuji Heavy Industries, the maker of Subaru automobiles, has released details of two innovative experimental engine technologies.
 

The Turbo Parallel Hybrid (TPH) is a revolutionary powertrain system to be used on a Hybrid Electric Vehicle (HEV) the company plans to launch experimentally in 2007.

The Lithium-ion capacitor (Li-ion), is expected to broaden the possibilities for batteries in future vehicles.

The TPH is a strategically important technology as the power source of clean-energy vehicles.

It will be incorporated with Subaru’s core technologies, the horizontally opposed Boxer engine and symmetrical All-Wheel Drive.

FHI has been developing the TPH with a view to future mass production.

The TPH system places a thin, 10-Kilowatt motor generator between a vehicle’s engine and its automatic transmission.

The combination of the motor generator and the boxer turbo engine adopts the “Miller cycle.”

As with conventional turbo models it provides superb drivability in the mid-speed ranges when the turbocharger is active, while also delivering excellent acceleration and fuel economy.

This all-range performance is enabled by Motor Assist, a feature designed to boost engine torque at low revolutions.

Compared to the SSHEV (Sequential Series Hybrid) system previously developed by FHI, the TPH excels in cost performance, as it uses a relatively more compact motor and a smaller battery.

In order to produce even better driving performance from the TPH, FHI plans to equip the system with high-performance manganese lithium-ion batteries, currently under development at NEC Lamillion Energy Co., Ltd.

The company was jointly established by NEC and FHI in 2002 for development of secondary batteries.

Energy density has been drastically enhanced in the Li-ion capacitor. It also retains the capability of instantaneous charge/discharge and the high durability of regular capacitors.

The capacitor’s negative electrode uses newly developed Li-ion occlusive carbon material, while its electrolyte is also made of Li-ion.

The technique enables occlusion of a large amount of Li-ion on the negative electrode in the new capacitor.

This helps boost the capacity of the negative electrode and increases the electrical potential difference, making high voltage possible without deterioration in positive electrode performance.

The principle of the Li-ion capacitor has potential for greater versatility and increased performance of capacitor occlusion.

Many new materials to be used for high-energy accumulation in capacitors have been tested and some progress has been made in this area of research.

The application of these new technologies will theoretically double the estimated accumulation capacity of capacitors available in today’s market.

FHI is currently conducting performance tests on prototype cells of the new Li-ion capacitor.

The eventual successful commercialisation of Li-ion capacitors for compact cars would open up many other business opportunities, including helping to meet the increased demand for new hybrid buses, trucks, and passenger vehicles.

The new capacitor also has the potential to be an alternative to conventional lead batteries in the future.

FHI is committed to the development of power storage technologies as the key to further promote the use of hybrid vehicles, fuel cell vehicles, and electric vehicles.

FHI has been working on development of power storage systems and the application of NEC Lamillion Energy-made high-capacity manganese Li-ion batteries to prototype hybrid vehicles, including the Subaru R1e, for further testing and evaluation.

This approach has allowed the company to acquire added technical value with minimum investment and to solve issues concerning the practical application and mass production of high-capacity manganese Li-ion batteries.

The TPH and Li-ion capacitor development projects are the latest in FHI’s power storage technologies, and the practical advances they represent illustrate FHI’s dedication to environmental technology development.