Mitsubishi Unveils One Electric and Two Diesel Concept Cars at Tokyo Motor Show

26 October 2007

The i MiEV Sport.

Mitsubishi Motors Corporation introduced three concept cars at the 40th Tokyo Motor Show: the electric i MiEV Sport; the Concept ZT sedan; and the Concept-cX compact SUV.

Based on the i MiEV (earlier post), the i MiEV Sport features Mitsubishi Motors’ in-wheel motors in the front plus S-AWC (Super All Wheel Control)—the company’s vehicle dynamics control system—to achieve high maneuverability as well as high levels of both environmental and running performance.

The drive system uses three permanent magnetic synchronous motors. One in-wheel motor is placed at each front wheel; a single motor drives the rear wheels, as is used in the i MiEV system. An E-4WD system electronically optimizes the output of all motors. In addition, a new E-AYC (Electric Active Yaw Control) system is employed to directly regulate torque at the left and right rear wheels via an electric motor. In addition to the E-4WD and E-AYC, the S-AWC system integrates ABS and ASC (Active Stability Control) systems, thus independently controlling driving force, traction and braking at all four wheels, for total maneuverability and maximum stability.

Performance profile for the Li-ion battery pack in the i MiEV. Click to enlarge.

The two in-wheel motors produce 20 kW of output and 250 Nm (184 lb-ft) of torque each; the rear motor, 47 kW of power and 180 Nm (133 lb-ft) of torque. Maximum speed is 180 km/h (112 mph), and the vehicle has a range of 200km (124 miles) in the 10-15 cycle.

Like the i MiEV, i MiEV Sport uses a rear-midship design in its layout. Making use of the relatively long wheelbase of this platform, a high-capacity lithium-ion battery is installed in the lowest area under the floor, and components including a motor and inverter are arranged beneath the luggage compartment. This layout provides optimal distribution of weight, front and rear, and a lower center of gravity for stability, sporty performance, and a spacious interior.

An aluminum space frame—a combination of aluminum extrusions and aluminum die casting—is light, rigid and strong; helping to improving performance by minimizing weight. The optimum layout of structural members, including front-side and cross members, efficiently absorbs crash energy in the event of front-end or side collision.

In a collision from the rear, EV components under the back seat and rear floor serve as a barrier to ensure the integrity of the passenger compartment. By making use of the rear-midship layout and utilizing Mitsubishi’s latest RISE (Reinforced Impact Safety Evolution) body, the concept realizes excellent occupant protection in collisions from any direction, even when colliding with a vehicle of different height or weight.

Effective use of energy is achieved by installing an auxiliary photovoltaic generator on the roof, a power-generating fan inside the front grill, and regenerative braking functions to recover energy when the car is slowing down. Much of the lighting is by bright, power-saving LEDs, including in the rear combination lamps and vehicle interior, and the efficiency of the air conditioning is enhanced by the use of heat-absorbing window glass. In addition, Green Plastic—Mitsubishi Motors’plant-based resin technology—is used wherever possible for interior components in another nod to the environment.

Earlier this year, Mitsubishi Corporation (MC), Mitsubishi Motors Corporation (MMC) and GS Yuasa Corporation established a joint venture (JV) company to manufacture large-capacity, high-performance Lithium-ion batteries that can be used in electric vehicles (EV). (Earlier post.)

The Concept-ZT uses a newly developed 2.2-liter diesel engine mated to the new Twin Clutch SST (Sport Shift Transmission).

The engine is a 2.2-liter 4-cylinder DOHC, 16-valve with VD (Variable Diffuser)/VG (Variable Geometry) turbodiesel engine with common-rail direct fuel injection (piezoelectric injector) that delivers a maximum output of 140 kW (188 hp) and maximum torque of 400 Nm (295 lb-ft).

The S-AWC system combines front E-LSD (Electric control - Limited Slip Differential), ABS and ASC with the 4WD electronic control system also used in Outlander and Delica D:5. This optimally controls driving force, traction and braking at all four wheels, and provides stable driving on various road surfaces under various conditions, realizing a pleasurable and safe driving experience.

As in the i MiEV SPORT, the aluminum space frame structure combines aluminum extrusion and aluminum die casting, not only realizing a body of great strength and rigidity, but contributing to weight reduction and crashworthiness. In addition, for the outer panels of hoods, fenders, doors and trunk lids, shock-resistant, recyclable resin is used, as seen on the front fender of the Delica D:5.

The Concept-cX uses a newly developed 1.8-liter clean diesel engine and Twin Clutch SST. The engine delivers 100 kW (134 hp) of power and 280 Nm (207 lb-ft) of torque. The 4WD-based integrated vehicle dynamics control system offers excellent running stability and versatility, and is also used in SUVs including the Outlander and Delica D:5.

Resources

• Development of Next-Generation Electric Vehicle “i-MiEV”