A closer look at Audi’s new R8 e-tron EV and battery

Author: Green Car Congress

Visually, the 4.40 meter (14.4 ft) long Audi R8 e-tron is recognizable by its unique lighting solutions on the air inlets, front apron and sideblades. Its exterior skin, painted in Magnetic Blue, combines body parts made of aluminum and carbon fiber reinforced polymer (CFRP), such as the front and rear lids.

The model line-up of the second generation of Audi’s high-performance R8 sports car, unveiled at the Geneva Motor Show earlier this year, includes the new R8 e-tron battery-electric vehicle. The new R8 e-tron delivers 340 kW (456 hp) of power; acceleration from 0 to 100 km/h (62.1 mph) in 3.9 seconds; and a driving range of up to 450 km (279.6 mi). Range for the first generation R8 e-tron was was 215 km (133.6 mi).

Available for order this year upon customer request, the new R8 e-tron uses a newly developed high energy density Li-ion technology optimized for a purely electric vehicle drive. Li-ion cell energy density was increased from 84 to 152 Wh/kg; in comparison to the first technology platform, the battery capacity has grown from 48.6 kWh to 90.2 kWh—without changing the package.

The R8 e-tron Audi Space Frame (ASF) is based on the multimaterial design of the V10 version, which is extended by a rear body module made of CFRP. Despite its low weight, the corrugated bulkheads that conceal the luggage compartment can absorb a lot of energy in a rear-end collision.

With aerodynamic modifications to its cooling air inlet, rear spoiler, diffuser, underbody and sideblades, the drag coefficient (Cd) of the R8 e-tron is just 0.28.

The T-shaped Li-ion battery is structurally integrated in the middle tunnel and is mounted behind the occupant cell—this location offers a low center of gravity and an axle load distribution of 40:60 (front/rear). The liquid-cooled lithium-ion battery pack consists of 52 modules. Compared to the first e-tron technology platform, the energy capacity of the new 595 kg (1,311.8 lb) battery system was boosted from around 48.6 kWh to 90.3 kWh without requiring any package modifications.

Full article: greencarcongress.com/2015/06/20150612-r8etron.html