With no mechanical connections between the front and the rear power units, the system is controlled entirely and automatically by electronics using “by wire” technology as used for the first time on the Hoggar, the concept car which appeared in 2003 and was equipped at the time with two HDi FAP diesel engines.

HYmotion4 technology is based on a parallel full-hybrid design using existing powertrain sub-assemblies.

Peugeot Prologue HYmotion4. The Prologue is a diesel-electric hybrid crossover. In the engine bay, it combines a 2-liter HDi diesel with particulate filter, a high-power Stop &Start system, and a six-speed automated gearbox. The high-torque, high-power electric motor is mounted in the rear.

The 2.0-liter HDi FAP engine in this car develops maximum power of 120 kW (163 bhp) at 3,750 rpm and a maximum torque of 300 Nm (221 lb-ft) at 1,580 rpm. It has a variable geometry turbocharger, an electronically controlled high-pressure pump and piezoelectric injectors. It is coupled with a particulate emission filter (FAP), which collects particles and then incinerates them in a special process exclusive to Peugeot’s HDi common rail technology combined with the use of an Eolys additive.

The synchronous permanent magnet motor develops continuous power of 20 kW (27 bhp) and has a transitory peak capacity of 27 kW (37 bhp). It generates a continuous torque of 100 Nm (74 lb-ft), with a peak of 200 Nm (148 lb-ft). It is coupled to an inverter, which controls the torque by regulating the current from the high-voltage battery pack. The latter operates in a voltage range of between 150 and 270 volts.

The Prologue HYmotion4 uses a NiMH battery pack located under the rear floor, near the electric motor.

The HYmotion4 concept car be driven in electric only mode (to start up, in town at speeds of less than 50 kph (31 mph) and when decelerating); in diesel engine only mode, at stable speeds on the open road or on motorways, when the diesel engine attains its optimal efficiency; and with both mechanical and electric power combined for extra boost or in four-wheel drive mode.

The concept has a fuel consumption rating of 4.1 L/100km (57 mpg US) and emits 109 g/km of CO₂—about 35% better than a comparable conventional vehicle with a 2.2-liter diesel engine, according to Peugeot.

RC HYmotion4. Peugeot uses “RC” to designate sports models in its range. The new RC concept, the full name of which will be introduced at Paris, “fills the gap” between the RC ♠ and ♦ concept cars revealed in 2002 and the 908 RC introduced in 2006, according to Peugeot.

The RC HYmotion4 combines a 1.6-liter 160 kW (218 bhp) THP gasoline engine fitted transversally in a central position at the rear of the vehicle with a 70 kW electric motor under the hood. Maximum torque is 178 Nm (131 lb-ft) from the front motor, and 280 Nm (207 lb-ft) from the rear engine.

The RC HYmotion4 features a lithium-ion battery pack, positioned in the central tunnel running through the passenger compartment. The RC HYmotion4 can be driven in electric only mode; in gasoline engine only mode; and in combined mode for extra power and all-wheel drive.

Acceleration from 0 to 100 kph takes 4.4 seconds, and from 80 to 120 kph in 3 seconds. Fuel consumption is 4.5 L/100km (52 mpg US), with CO₂ emissions of 109 g/km in the combined cycle (or zero in electric mode).

The Hypnos. Click to enlarge.

Hypnos. Citroën’s Hypnos represents another diesel application of the HYmotion 4 system. In this vehicle, the HYmotion system combines a front-mounted 147 kW (200 bhp) 2.0-liter HDI DPFS diesel engine with 420 Nm of torque; Stop& Start system; a six-speed electronic gearbox system; and a 37 kW (50 hp), 200 Nm (148 lb-ft) electric motor on the rear axle.

Hypnos offers an all-electric range of around 3 km (1.9 miles) at 50 kph (31 mph). Combined cycle fuel consumption is 4.5 L/100 km (52 mpg US) for CO₂ emissions of 120 g/km.

C4 WRC HYmotion4. The C4 WRC hybrid concept is the first World Rally Car to be equipped with a hybrid energy recovery system. The WRC hybrid uses a front, transversely-mounted 2.0-liter engine that develops 320 hp at 5,500 rpm and 569 Nm (420 lb-ft, 58 kg-m) of torque at 2,750 rpm. A rear-mounted 125 kW electric motor is supported by a 400V, 22 Ah lithium-ion battery pack comprising 990 cells.

Two additional cooling systems support the motor-generator and battery pack, with a specific radiator positioned under the right-hand side of the floor.