Toyota Prius+

The Toyota Prius+ is a new vehicle, designed from the ground up. Its advanced, cutting-edge exterior design hallmarks it as an evolution of the original Prius.

Though still compactly sized to optimise its aerodynamic performance, the Prius+ provides, as its name suggests, a significant increase in space and passenger accommodation. It is 135 mm longer than a standard Prius, 30 mm wider, and 85 mm higher, with a wheelbase extended by 80 mm, making it possible to accommodate 7 people in three rows.

Instantly recognisable as the latest member of the Prius family through its characteristic, triangle silhouette, the new Prius+ combines Toyota’s Under Priority frontal design language with painstaking airflow management to give the new 7-seat full hybrid uniquely clean, advanced and cutting-edge styling.

To gain the full benefit of its lightweight, high tensile steel and aluminium construction and its uniquely quiet Hybrid Synergy Drive® powertrain, the Prius+ exterior design focuses on maximising aerodynamic efficiency to improve fuel economy, handling stability and quietness.

The front of the new Prius+ features the latest representation of Toyota’s trapezoidal, Under Priority design. Featuring chrome-plated horizontal trim, the upper grille opening has been kept as small as possible to maintain a smooth airflow over the upper body. In contrast, the lower grille has been enlarged to increase engine cooling efficiency.

The tops of the sharp-edged, halogen headlamp clusters feature an adaptation of the curved line detail first seen on the current generation Prius, reinforcing the new full hybrid’s position within the Prius family line-up.

Housing LED Daytime Running Lights (DRLs), the flat, vertical surfaces of the bumper extremities not only reinforce the car’s broad stance and driving stability, but also create ‘aero-corners’ which correct the airflow as it passes over the front wheels to minimise turbulence within the wheelarches.

In profile, the iconic, Prius family triangle silhouette is instantly recognisable. The Prius+ evolves this design DNA with a strong spindle shape created by the long, seamless flow of the bonnet, A-pillar and roofline, the clean sweep of full-length side glazing emphasised by blacked-out B- and C-pillars, and a rising crease in the lower bodywork which flows smoothly into the rear bumper.

Distinctive rear styling is highlighted by a practical, top hinged tailgate flanked by large combination lamp clusters with Synergy Blue ornamentation, which flow round the corners of the bodywork to enhance visibility. The rear combination lamps are spaced as widely as possible, not only maximising tailgate opening width but also reinforcing the vehicle’s broad, stable rear stance.

The smooth convergence of airflow from the roof and sides of the bodywork is important to the aerodynamic efficiency of the new Prius+. The body itself tapers in plan form, and the flow of air away from the vehicle is smoothed by a roof spoiler optimised for length and angle, an ‘air kick’ shape built into the rear combination lamp clusters, and aero corners to the rear bumper.

In addition, front and rear spats fitted at the front of each wheel arch suppress airflow changes around the tires, improving straight-line stability and steering performance.

In combination, these comprehensive aerodynamic measures award the new Prius+ a class leading drag coefficient of just Cd 0.28.

The presence of Hybrid Synergy Drive® is denoted by hybrid blue lamp ornamentation and Toyota badging, and the front wing ‘Hybrid’ badge. The new Prius+ is available in a range of seven exterior colors, including Toyota’s unique White Pearl finish.

The 16” alloy wheels with aerodynamic wheel caps and the 17” aluminium alloys both feature tires with a 5% lower rolling–resistance than those fitted to the standard Prius.

The dynamic architecture of an all new interior design features a horizontal dashboard which encompasses the centre console, centre cluster and instrumentation in one flowing form. Combined with concave door trim and a well-defined centre space between console and cluster for connecting driver and front passenger, this creates an unprecedented sense of spaciousness.

The console flows into a dashboard-top mounted centrally position instrument binnacle, allowing for excellent visibility. Within the binnacle, the Hybrid System Indicator, speedometer and gear shift indicator are positioned close to the steering wheel, minimising driver eye movement from the road.

Instrumentation and switchgear within the centre console and centre cluster is clearly divided between driving operation controls and all other functions. All driving related switchgear is positioned adjacent to the steering wheel, and mounted within a metal-like surface finish.

The Toyota Touch multi information screen -incorporating audio, navigation and vehicle information systems- and the air conditioning controls are mounted within a high quality black background finish. The air conditioning system features a new, single dial controller, which allows for the adjustment of temperature, mode and fan speed through the simple, intuitive action of a single knob.

The new Prius+ interior is hallmarked throughout by contrasting finishes and soft touch materials, combining an advanced look and feel with operational practicality. A choice of two interior color schemes –Aqua and Grey- may be combined with two grades of fabric upholstery, or ‘Toyota E-Tex’ – a highly durable synthetic material which has the texture of leather yet is 30% lighter and may be readily wiped clean.

At 2,780 mm, the new Prius+’s wheelbase is 80 mm longer than that of a standard Prius. The vehicle rear overhang is also 50 mm longer, ensuring that both passenger accommodation and loadspace are significantly more spacious that those of the standard Prius.

The new Toyota full hybrid’s seven-seat format features three, independent, sliding/split/folding second row seats and a 50:50 split/folding third tier. The adoption of third row seating has been made possible by the installation of a highly compact, space-saving lithium-ion battery pack within the vehicle centre console between the front seats.

The couple distance between front and second row seats is 965 mm, 35 mm longer than Prius. And the couple distance between first and third row seats is a class-leading 1,635 mm. Both second and third tier knee room has been further improved by 25 mm through the use of a thin, curved front and second row seatback design.

Clear forward visibility for all occupants has been realized by raising the seating height of each row by 45 mm over that in front, while maintaining ample head clearance in every row.

The Prius+’s full hybrid system features a 1.8 litre VVT-i petrol engine, a powerful electric motor, a generator, a high performance lithium-ion battery, a power control unit, and a power split device.
The HSD system uses power from both the petrol engine and electric motor in tandem, as well as alone, maximising the efficiencies of both units to achieve the optimum balance of driving performance and fuel efficiency.

During deceleration and under braking, the electric motor acts as a high-output generator to effect regenerative braking. Normally wasted as heat, kinetic energy is recovered as electrical energy for storage in the high performance battery.

The system’s seamless, E-CVT electric continuously variable transmission is controlled by Shift-by-Wire technology, using an electronic shift lever system.

As in the standard Prius, the Prius+ features three ‘on-demand’ drive modes to increase the capabilities of the full hybrid powertrain, including a full hybrid-unique, EV mode which allows for ultra-quiet running on electric motor power alone, resulting in zero fuel consumption and CO2, NOx and PM emissions.

The Prius+’s lithium-ion battery replaces nickel-metal hydride technology within a non-plug-in Toyota full hybrid for the first time. Located within the vehicle centre console between the front seats, the new battery is significantly lighter and more compact than that of the Prius.

A new cell structure design equips the lithium-ion battery with just 56 cells arranged in a vertically double stacked structure. This occupies significantly less volume than a Prius battery and, at 34 kg, is 8 kg lighter.

Despite these reductions in both size and weight, the Prius+ battery has the same rated voltage of 202 V, and has an identical maximum output.

The lightweight, highly compact, 4-cylinder 1,798 cc Atkinson cycle petrol engine develops 98 DIN hp/73 kW at 5,200 rpm and 142 Nm of torque at 4,000 rpm. Combined with a cooled Exhaust Gas Recirculation system, the adoption of the Atkinson cycle offers significant gains in fuel efficiency and the reduction of emissions.

Because the intake valves close late in an Atkinson Cycle engine, compression is delayed. This creates a high expansion ratio for less compression, reducing intake and exhaust energy losses and converting combustion energy to engine power more effectively. As a result, the exhaust temperature is lower than
that of conventional engines. Cooled Exhaust Gas Recirculation reintroduces cooled exhaust gas into the intake system, further reducing engine operating temperatures.

Together, these technologies minimise situations when the cooling effect of ‘fuel enrichment’ is necessary to protect the catalytic converter from overheating damage, thereby improving fuel economy and lowering emissions.

Improving cold weather fuel economy and cabin comfort, an engine heat management system combines an improved Exhaust Heat Recirculation system with an electric water pump. To reduce mechanical losses, an electric system replaces the conventional water pump drive belt. As a result the coolant flow rate can be controlled with greater precision, contributing to greater fuel efficiency.

Housing the electric motor, generator, power split device and double-motor reduction mechanism in one lightweight, highly compact transmission casing directly comparable in size to that of a conventional gearbox, the transaxle lies at the heart of the Hybrid Synergy Drive® system.

The high performance, permanent magnet, synchronous 60 kW electric motor/ generator works in tandem with the petrol engine to boost acceleration and power the driven wheels alone when the Prius+ is operating in EV mode.

Similar in size to a 12 volt battery, the Hybrid Synergy Drive® power control unit consists of a voltage boost converter, an inverter and a DC/DC converter.

Controlled by the motor control ECU from the Power Management ECU, the Power Control Unit boosts the DC voltage level from the hybrid battery and converts it to AC electricity to drive the electric motor.
A conventional, non-hybrid vehicle is equipped with an alternator to charge the auxiliary battery. However, because an alternator cannot operate during engine cut-off driving mode, a full hybrid vehicle requires an alternative system. Hybrid Synergy Drive® incorporates a DC/DC converter to reduce the high voltage of the 202V system battery pack to 14V, supplying power to the accessory systems and charging the auxiliary battery.

The Prius+’s Hybrid Synergy Drive® powertrain combines the 99 DIN hp/73 kW output of the 1.8 litre petrol engine with the 60 kW output of the electric motor for a maximum system power output of 136 DIN hp. The Prius+ will accelerate seamlessly from 0-100 km/h in 11.3 seconds and has a top speed of 165 km/h.

Its environmental performance enhanced by the Prius+’s class-leading aerodynamic performance and low weight, the full hybrid drive system returns both class-leading fuel economy and CO2 emissions of 4.1 l/100 km1 and 96 g/km1 respectively.

As with every vehicle in the new Prius family, the Prius+ is a front-runner in the field of cutting-edge technological innovation.

Its comprehensive standard equipment specification includes highly fuel-efficient air conditioning, a Head-up Display system linked to steering-wheel mounted Touch Tracer control switches, a smart entry system, Hill Start Assist and Toyota Touch -the world’s most affordable touch screen multimedia interface.

Just as in the Prius, customers are offered a range of advanced convenience and safety features to choose from. Options include a panoramic resin sunroof, LED headlamps, a Pre-Crash Safety system incorporating Adaptive Cruise Control, Intelligent Park Assist, Toyota Touch & Go Plus and Toyota Touch Pro navigation systems, and a JBL Matrix Premium Sound System featuring GreenEdge technology.

Source: Toyota press

Gallery: Toyota Prius+