After crossovers and SUVs, the next big shift for the car manufacturers is towards electrically-powered vehicles, with hybrid or fully electric powertrains. Even the luxury brands are headed in that direction so that they will have at least one or two models to offer by the next decade. At Aston Martin, development of the company’s first all-electric car for sale – the Rapide E – is progressing steadily towards beginning production which will be strictly limited to 155 units. Deliveries will take place during the fourth quarter of 2019.
Working closely with Williams Advanced Engineering (WAE) as its development partner, Aston Martin has utilised the hugely successful leader in electric vehicle (EV) technology to kickstart a new era for Aston Martin’s powertrain technology and overcome the technical challenges associated with packaging the battery system and motors within the space available.
Throughout the development process, the engineering team has focused on achieving effective cooling of the batteries and motor to ensure consistent performance, while strict weight targets have been stringently observed using lightweight alloys and carbon composite materials.
The Rapide E will be powered by an 800V battery electrical architecture with 65 kWh installed capacity using over 5,600 lithium ion 18650 format cylindrical cells. These are mounted in a bespoke battery pack where the original 6-litre V12, its gearbox and fuel tank were located. This battery system will power two rear mounted electric motors producing a combined target output of just over 610 ps and a colossal 950 Nm of torque.
The range target is over 320 kms and recharging of the battery pack can be either with a 400V 50kW charger or, because the car has an 800V high-voltage battery system, faster charging is possible using an 800V outlet delivering 100 kW or higher.
Being an Aston Martin, the Rapide E is being developed with a high-performance objective. Projected top speed for the Rapide E is 250 km/h, with a sub-4 second 0 – 60 mph (0 – 92 km/h) time. Aston Martin stresses that these figures are not restricted to a narrow window only when the batteries are fully-charged. Instead the target is for maximum performance on-demand throughout majority of the battery state of charge window, as would be expected from a conventional internal combustion-engined car. This includes the ability to drive a full lap of the Nurburgring circuit with absolutely no derating of the battery and the ability to cope with the daily demands of repeated hard acceleration and braking.
The car’s exterior and underbody has also been aerodynamically optimised and complemented with newly-designed aerodynamic wheels. Shod with low rolling-resistance tyres featuring noise-cancelling foam, the Rapide E aims to achieve higher levels of aerodynamic, frictional losses and cooling performance over the standard Rapide S.
It has also been an objective of the project team to retain and enhance the feel, character and delivery of the V12-engined Rapide S. To this end, careful attention will be paid to the development and tuning of both the electric powertrain and the chassis, with particular focus applied to software integration. The rear-wheel drive Rapide E’s twin electric motors will drive through a Limited-Slip Differential, which combined with revised spring and damper rates ensures the pure handling characteristics for which the petrol-powered Rapide S is already renowned.
Though the Rapide E will be built in low volumes, it is being subjected to Aston Martin’s stringent and exhaustive testing protocols, with the dedicated WAE team working closely alongside Aston Martin personnel to ensure every aspect of the prototype test programme follows the marque’s established procedures. Uniquely, customers will be an extended part of the ongoing programme, with their comments and driving experiences providing feedback that will help shape and improve future Aston Martin EVs.
Explaining the Rapide E programme, Andy Palmer, CEO Aston Martin, said: “Environmental responsibility and sustainability is a global challenge faced by us all. As a career automotive engineer, I’m proud that the car industry is leading the way in finding long-term solutions and reducing harmful emissions. As Aston Martin’s CEO, I take particular satisfaction working with Williams Advanced Engineering and our other associated technology partners to bring Rapide E to reality.”
“As our first all-electric production model, Rapide E will fast-track our knowledge and help us ensure the character and high-performance capabilities of our future EV models and enhance the unique qualities found in all Aston Martins as we know them today. Rapide E will also serve as a critical step on our path to re-launching Lagonda as the world’s first zero-emission luxury marque,” he said.