Mitsubishi Goes PHEV for 4WD models

By Lee Pang Seng
MITSUBISHI has already demonstrated its ability to produce electric vehicles for the urban environment with the i-MiEV (Mitsubishi Innovative Electric Vehicle), and is making the car more attractive by reducing price gradually in key markets. The next step was to develop an electric vehicle for inter-city driving and the result is the PHEV (plug-in hybrid electric vehicle).

The PHEV goes one step further than the hybrid cars we see on our roads today: it runs on electric power for primary mobility rather than as an added boost to engine output. In short, it works the other way round in which engine power is brought into play to assist in overtaking, driving up an incline or when cruising at high speed on the highway.

The engine is also used to charge the drive battery as well as the use of regenerative braking in which kinetic energy generated by the vehicle during braking is used to charge the drive battery. With a constant electrical charge, the PHEV can perform its urban motoring function for a greater distance. The use of the engine on highway drive also ensures that greater mileage can be enjoyed: Mitsubishi says the PHEV it has developed can cover almost 900km.

This is applied to the Outlander, an SUV (sports utility vehicle) model: the system comprises a lithium-ion battery that is centrally located beneath the passenger cell, two electric motors – one each in front and rear, and a 2.0-litre engine. Mitsubishi develops the system for use in mid-size and large vehicles, including 4WD vehicles that it has the expertise in making.

A unique engineering feature is the use of electricity to link both the front and rear axles so that they work together to qualify as a four-wheel drive. Unlike the conventional four-wheel drives, whether part-time or full-time systems, there is no mechanical link between the two transaxles. Each is driven by the respective power source: the front has the 2.0-litre engine and an electric motor, while the rear is driven only by its own electric motor.

This is managed by the S-AWC (Super All Wheel Control) that is said to provide ‘incredible traction, solid stability and intuitive, linear handling’ in challenging terrain by combining Active Stability and Traction Control (ASC) and the electronically controlled Twin Motor 4WD and AYC (active yaw control).

The 4WD Lock button is pressed when the road is slippery to simulate locking of a centre differential and distribute torque equally to all four wheels for better traction and stability. The ASC comes into play by automatically adjusting engine output and applying braking force at the appropriate wheel to prevent skidding on slippery surfaces.

It is all automatically done just like the drive system, which is selected based on vehicle and driving conditions. EV Drive Mode (electric power mobility) is selected for normal drives up to 120km/h. Series Hybrid Mode (electric power and engine assistance) is engaged on hard acceleration (to drive away quickly from the lights or for rapid passing manoeuvres) or going uphill. The engine generates electricity when the battery level is low and to increase power.

The third option is Parallel Hybrid Mode, which is engine power plus electric motor assistance. This is for high speed driving when the engine powers the vehicle at the point when its efficiency is high and gets assistance from the electric motors when extra power is required. Surplus power is used to charge the battery. This is the hybrid mode that is currently applied to the hybrid cars here.

In output, the 2.0-litre engine with double overhead cams, 16 valves, MIVEC (variable valve control) and ECI-MULTI electronic fuel injection delivers a modest 89kW (121PS) at 4500rpm and 190Nm at the same peak rev of 4500rpm. The front electric motor puts out 60kW (82PS) and 137Nm while the rear electric motor, which is bigger, delivers more torque of 195Nm with the power being the same as the front unit.

The transmission is simple being the front and rear transaxles with a single speed ratio each. On electric power alone, the mileage is 60km but the combined mileage is rated at 1.9 litre/100km or 52.6km/l/. There are paddle shifts on the steering wheel but they are not for the manual selection of gears. They are for the rate of regenerative braking strength. There are six levels and the higher the level, the greater the vehicle retardation.

To demonstrate the mobile practicality of the Outlander PHEV, Mitsubishi entered the vehicle in the FIA Asia Cross Country Raid 2013 that started in Thailand and ended in Laos. The event covered challenging terrain of all forms and the Outlander PHEV turned out to be a ‘successful finisher’ in that it completed the gruelling off-road raid.

We had a taste of what the Outlander PHEV could do on tarmac late last year in Japan, during the time of the motor show. Mitsubishi Motors arranged for a drive impression at the Mobara twin circuit in the Chiba Prefecture, an area to the east of Tokyo across the Tokyo Bay. The 2km circuit was laid out with cones to simulate a variety of driving conditions so that we could feel the changes in driving modes and regenerative charging.

Electric cars always take off briskly as a lot of torque is generated right from the beginning and the Outlander PHEV was no different in that respect, despite its kerb weight of 1810kg. It was as good as driving a smaller and lighter car. The multi-info on the central dashboard area gave clear visuals of the power that was being used to drive the car, as well as the rate of battery charging.

The latter was seen each time we hit the brakes for a corner or to enter a coned slalom. When we hit the accelerator pedal hard to pick up speed, we could see the engine light coming on to charge the battery as electricity was being drained to gain speed. This was also clearly the case when we accelerated up an incline that was part of the circuit.

We also found the Outlander PHEV quite quick through the respective corners, tyre squeals and all due to the higher than recommended speeds that we were driving. Body roll was well checked with anti-roll bars for the MacPherson strut front and multi-link rear. The centrally located lithium-ion battery also played its part here in keeping the SUV stable. We could enjoy the Outlander’s dynamic qualities and the quiet and strong way in which it ‘zipped’ along.

The large lithium-ion battery has a 12kWh capacity, which is more than enough to boil water for picnics, via a special 12V plug point at the rear. The rear luggage door can also be electrically opened and closed. Some active safety features include adaptive cruise control, forward collision mitigation system, lane departure warning system, and hill start assist. It is not short on features such as keyless entry, push button start/stop, sunroof, among them.

To charge the lithium-ion battery, you can opt for quick 30-minute 80-per cent charge at dedicated outlets or home charging (six hours). There are two charging points for the respective charge to be made, while the fuel filler is on the other side of the Outlander PHEV.

Will the Outlander PHEV be introduced in Malaysia? Given the recent NAP announcement, it would seem unlikely unless one is willing to pay a premium for the exclusivity of owning an imported Outlander PHEV. It is also not feasible to assemble the Outlander PHEV here to enjoy the tax savings. An idea of its price in Japan shows that it costs 800,000 yen (about RM26,000) more than the conventional model but the government subsidy for clean vehicle purchase has reduced the difference to 400,000 yen.

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