The REEV project network. Click to enlarge.

The 402bhp (300kW) mid-engined, twin-motor sports car is capable of accelerating from 0-60 mph in 4 seconds and 0-130 mph in 30 seconds burst. On the NEDC cycle, CO₂ emissions are 55g/km over a 300-mile combined range. Within its compact 4.464m length, the two-seater EMERG-E contains a pair of electric motors, a lithium-ion battery pack, four inverters, a three-cylinder range-extending internal combustion engine and a gasoline tank. All this is wrapped within highly aerodynamic, light bodywork.

Infiniti has a deep knowledge of what an internal combustion engine is because this is what we are providing, and we also have a deep knowledge of what hybrid is which we are also providing in the market right now.

This is about changing the rule of the game. You have more and more cities in Europe that are banning internal combustion engine emissions, but with this car you can run downtown in London, for example, with no guilt—you are not guilty, because you are zero emission. At the same time, you’re going to have fun on a racetrack with the maximum performance you can enjoy.

—Francois Bancon, Division General Manager of Exploratory and Advanced Product

EMERG-E was designed under the direction of Shiro Nakamura, Senior Vice President and Chief Creative Officer. While some of Nissan Global design bases were involved in this project, the overall design development were mainly led by Nissan Design Europe (NDE), Paddington, London and built by Nissan’s European Technical Centre (NTCE), Cranfield.

TSB. The TSB provided the chance to access new technologies and work with a variety of organizations, including universities, suppliers and OEMs. The opportunity to work in the REEVolution consortium (earlier post)—co-funded by the TSB as part of its Integrated Delivery Programme (IDP) Competition for Low Carbon Vehicles, and by the consortium members—revealed that fellow member Lotus Engineering was also developing a range-extender electric sports car; the two companies decided to collaborate.

That decision, explains Bancon, was eased by the fact that Nissan (and Infiniti) have had a relationship with Lotus for 10 years, mostly about methodology. Further benefits included co-funding of the EMERG-E project from the TSB, and access to a range of highly innovative suppliers.

A key feature of the INFINITI EMERG-E Concept is that it contains a blend of technologies and solutions that have not previously been tried, as required by the TSB funding rules. The sharing of several components by other members of the consortium is also an element of the TSB initiative, the aim being to promote developmental economies of scale, although the approach to their deployment differs.

A key aim of the TSB approach is to develop projects that are closer to commercial reality. So there’s more of a chance of the technology making it to market.

—Jerry Hardcastle, Vice-President Vehicle Design and development, the Nissan Group Technology Centre Europe and senior member of the UK’s Automotive Council

Infiniti will produce two fully functioning EMERG-E prototypes in the next step of this concept development program.

Technology. EMERG-E is a range-extender electric vehicle, and it is propelled at all times by a pair of 201 bhp (150kW) EVO Electric axial flux motors driving the rear wheels. (The motors are also used in the range-extended Lotus Evora 414E Hybrid.)

The EVO motor design offers a range of weight, volume, efficiency, control, and manufacturing advantages, and is characterised by extremely high power and torque densities. The low-weight and small footprint of the Axial Flux machines enable electric-drive vehicle manufacturers such as Lotus and Infiniti to develop lighter, smaller and more efficient hybrid and electric propulsion systems.

The motors direct their power via a single speed Xtrac transmission (4.588:1 reduction box) to create what is effectively an open differential, this arrangement significantly reducing driveline friction losses. A quartet of inverters controls the motors and their energy regeneration role under braking, the recovered power being directed to a lithium-ion battery mounted behind the seats.

The 300 kW lithium-ion phosphate battery pack can be recharged from the grid (domestic and fast-charge) and stores sufficient energy (14.8 kWh) to propel the EMERG-E for 30 urban miles, at which point the on-board gasoline engine starts up to act as a generator. Recharge time from 13 amps takes 10 hours, or 6 hours at 16 amps.

This light, ultra-compact, Lotus Engineered three-cylinder 1.2 liter 35kW engine has been purpose-designed for its range-extending role. (Earlier post.) It operates between crank speeds of 1500-4000 rpm, producing peak power at only 3500 rpm.

The EMERG-E high performance, low-emission propulsion system is installed within a lightweight, extruded aluminium chassis unit to which ultra-light carbon fibre panels are attached. Infiniti is keen to explore the potential for this material in future low production volume models, given that it provides a 20% strength-gain in tandem with a 50% reduction in weight.

EMERG-E has been developed for aerodynamic performance, both to reduce energy-draining drag—which stands at 0.34—and to generate positive downforce, and downforce balance, to enhance its high-speed handling.

EMERG-E features the double wishbone suspension of race-car practice, its arms of aluminium to save weight. Its carbon fibre panels have been developed in the UK in conjunction with a number of leading motorsport specialists (Lola Composites, supported by Cranfield University), with the aim of using the material in higher volumes than has previously been possible.

Mid-ship design. While Infiniti has always had rear-wheel drive styling, says Nakamuyra, a mid-ship layout usually has a different attitude. Furthermore, a mid-engined car was never a part of the original plan for Infiniti or its design philosophy.

Designing a mid-ship car sounds very exciting, but at the same time there’s even less freedom because of the package constraints and the distribution of weight. Because of the FX and Essence, we have already established an Infiniti look and proportion. Also, we now have front-wheel drive cars with ETHEREA. We’ve got to go beyond our existing proportions, so this is a good experience.

—Shiro Nakamura

Infiniti created three-quarter scale model proposals from Infiniti studios in Japan, the UK and California. The winning design, the work of California-based Infiniti designer Randy Rodriguez, was recreated as a full-size clay model constructed at Nissan Design Europe’s Paddington studio.

The aim has been to combine the brand’s characteristic long nose with the heavier volume at the rear, while maintaining what Nakamura calls “the emotional flow of an Infiniti.” Unlike most mid-engined cars, EMERG-E is not a wedged design.