Infiniti Looking To Bridge Gap To Mass EV Adoption

by Infiniti | November 4, 2019

NASHVILLE, Tenn. – Central to INFINITI's electrification strategy is the brand's new gas-generated EV powertrain, which establishes a new propulsion blueprint for many of the brand's future models. Offering the thrilling, instantaneous, silent acceleration of a high-performance electric car, this new powertrain eliminates two of the perceived obstacles to EV uptake among consumers – range confidence and the practicalities of recharging.

Propulsion is delivered to all four wheels through a pair of high-output electric motors. Power comes directly from a high-discharge, low-capacity battery pack, which is recharged constantly by a three-cylinder 1.5-liter gasoline generator based on INFINITI's revolutionary VC-Turbo variable compression ratio technology. The result is a powertrain which delivers the serene, immediate performance of an electric car, and the convenience of a gasoline-powered vehicle – with significantly reduced emissions.

'For three decades INFINITI has built a reputation for introducing powertrains that excite and empower drivers,' comments Eric Rigaux, General Manager, Product Strategy & Planning for INFINITI Motor Company. 'Our new gas-generated EV powertrain represents the next step into our electrified future, acting as a bridge to full electrification and setting the tone for our upcoming zero and ultra-low emission cars. However they are powered, our cars will offer thrilling yet serene electric performance, and e-AWD systems which inspire driver confidence.'

INFINITI will electrify its portfolio in the next two years, almost every future model from INFINITI will offer drivers a choice of gas-generated and pure EV powertrains.

A bridge to full electrification: one platform, two powertrains

In the future, INFINITI's new 'two powertrains, one platform' development direction will see the creation of vehicles which accommodate both gas-generated and fully-electric powertrains.

INFINITI's new gas-generated EV powertrain will fit many of the same platform touchpoints as an electric powertrain, with each system delivering battery power to a high-performance e-AWD (electric all-wheel drive) system. The platform of INFINITI's future electrified cars will be engineered to accommodate a pair of high-output electric motors – one on the front axle, one on the rear.

For electric vehicles, the space between the two axles will be given over to a high-capacity battery pack. Vehicles equipped with INFINITI's gas-generated EV powertrain will see the same space occupied by a significantly smaller battery pack, fuel tank and exhaust system, with the 1.5-liter VC-Turbo generator located at the front to feed power to the battery pack. In both instances, drive is provided solely by electric motors.

While INFINITI's new platform will accommodate both gas-generated and full EV propulsion systems, its inherent flexibility will allow the brand to develop a range of models that share many of the same components. The shared use of sub-assemblies, such as suspension and electric motor mounting units, will see the brand benefit from both development and production efficiencies. The new platform will also make it easier for INFINITI to develop cars that are ideally suited to specific market requirements.

'This approach to powertrain and platform development will result in vehicles which offer greater cabin space and refinement, and addictive accelerative performance from a powerful e-AWD system,' comments Rigaux. 'The high level of commonality between the two powertrains also creates efficiencies during the development process for each new car, giving us the flexibility to offer drivers the powertrains they want.'

Electric cars powered by gasoline: how it works

INFINITI's new gas-generated EV powertrain will see the introduction of a series of electric cars powered by gasoline. Power is provided directly to two high-output electric motors – one on each axle – by a battery pack located beneath the floor of the cabin, varying in capacity from 3.5 to 5.1 kWh depending on model.

As an electric car powered by gasoline, the character of the power delivery is as addictive, smooth and serene as in a high-performance battery electric vehicle. With instantaneous, electrifying responses to accelerator inputs, the electric motors provide their maximum torque from 0 rpm. The powerful motors deliver a total power output of between 185 and 320 kW (248 hp to 429 hp), depending on the vehicle. Acceleration, as in any electric vehicle, is totally linear, with higher-powered versions of the powertrain able to accelerate from 0-to-62mph in around 4.5 seconds. Furthermore, the driver and passengers won't experience the same 'shift shock' often associated with changing gear in a conventional hybrid or ICE (internal combustion engine) vehicle.

The battery pack is recharged constantly by the beating heart of the powertrain: INFINITI's new 'MR15DDT' engine. This three-cylinder 1.5-liter gasoline generator – the first-ever application of this engine – uses INFINITI's VC-Turbo innovative variable compression ratio technology, delivering a continuously variable rate of charge to the battery.

Crucially, the use of a gasoline generator means these vehicles will never need to be plugged in for hours to recharge. Indeed, they won't have a charging port at all. The powertrain requires only a short stop at a gas station to refill the fuel tank, removing concerns about range.

Despite the high level of performance on offer, emissions for vehicles featuring the new gas-generated EV powertrain will be significantly reduced compared to existing vehicles from the brand, and other ICE vehicles offering similar power and performance. Importantly, the system breaks the historic link between city driving and higher emissions, with the MR15DDT generator having to work less at low speeds to power the battery pack. The result is lower emissions and improved driving range in urban environments, where emissions for ICE vehicles are generally higher.

Serene Performance: Isolating the MR15DDT Generator

INFINITI vehicles equipped with the gas-generated EV powertrain will feature a series of advanced and world-first technologies and features to create the quiet, refined ride associated with conventional electric vehicles.

One of the most striking innovations is a world-first independent mounting system for the MR15DDT generator system beneath the hood, ensuring that engine noise and vibrations are virtually unnoticeable at any driving speed. To maintain calm and serenity in the cabin, the engine and electric motors are fully encapsulated to reduce audible engine noise and motor whine. The engine's independent mount system features fluid-filled mounts, designed to absorb any further vibrations that it may otherwise send through the body.

The MR15DDT VC-Turbo engine itself is uncommonly smooth, with significantly reduced noise and vibration levels compared to conventional in-line engines. This is a result of its multi-link design, where the piston connecting rods are almost vertical during the combustion cycle, rather than moving wider laterally as they would in a traditional crankshaft rotation. This represents the ideal reciprocating motion, and entirely negates the need for balance shafts found in other in-line engines.

Inside the cabin itself, INFINITI's gas-generated EVs are expected to offer Active Noise Cancellation, which will further counter any low frequency noises from the engine and road by producing opposing sound waves. This neutralizes unwanted noises in the cabin, and ensures a quieter, more peaceful ride.

These engine isolation and active sound control measures mean the system will never be more audible than any residual wind and road noise generated through driving. Combined with quiet tires, carefully tuned suspension systems, acoustic glass, and other passive soundproofing measures, vehicles equipped with the new gas-generated EV powertrain will offer a supremely serene ride, whatever the conditions.

Photo credit: Infiniti
posted on conceptcarz.com