The new battery cells are primarily responsible for the new performance and driving range of the Audi R8 e-tron. Audi has systematically adapted its high-voltage battery system to the specific needs of electric cars – the primary focus was on achieving an optimal ratio between power and energy. The results: The R8 e-tron has a significantly longer driving range and even more power than the previous model. In developing the high-voltage battery, the brand with the four rings followed the principle of maximum flexibility without losing sight of synergies in electrification. Its flexible cell module concept makes the Audi brand well-equipped for all future market developments, while the modular concept also guarantees Group-wide use across different car models.
The battery operates with 385 volts of nominal voltage, and its new cell module concept achieves excellent performance. The battery’s energy density grew from 84 watt-hours per kilogram (Wh/kg) to
152 Wh/kg, and its nominal capacity from 48.6 kWh to 90.3 kWh. Its driving range on a full charge has more than doubled – from 215 km (133.6 mi) to as much as 450 km (279.6 mi). These values make Audi the leader among the competition.
The battery system of the Audi R8 e-tron takes on the shape of a “T”. It measures 235 cm (92.5 in) long, 136 cm (53.5 in) wide and 70 cm (27.6 in) high, including the junction box on the cross-bar of the “T”. This junction box is responsible for monitoring, switching and transmitting an electrical current of over 1,200 amperes. The highly complex battery system consists of over 10,000 individual parts.
The 7,488 cells are packed in 52 modules of 144 cells each. Each module weighs 7.8 kg (17.2 lb). They are arranged on two and five levels (“floors”) in the tunnel battery and in the rear battery. Aluminum plates separate the “floors” from one another while creating the supporting structure for the battery.
Coolant circulates in a cooling system of aluminum shells. In a crash, high-strength floor plates and impact plates redirect the crash forces into the multimaterial ASF (Audi Space Frame) of the R8 e-tron in a defined way.
40:60: ideal axle load distribution
The 595 kg (1311.8 lb) battery system is joined to the ASF with bolts in the middle tunnel and behind the occupant cell, making it an integral part of the vehicle structure. Its mounting position results in a low center of gravity and an axle load distribution of 40:60 (front/rear), which is ideal for a mid-engine sports car.
The Combo 2 charging interface of the Combined Charging System in the Audi R8 e-tron enables charging with AC or DC electricity. When charging with AC from an industrial electrical outlet with 7.2 kW of charging power, a full charge is reached in just around 12 hours. Charging with DC electricity shortens the time – to just 95 minutes at a charging power of 50 kW. Audi is demonstrating charging equipment that can charge this battery system with up to 150 kW of charging power. For the driver of the R8 e-tron, this means that a driving range of around 150 km (93.2 mi) can be attained after just 15 minutes of charging time. The customer can manage charging remotely as well – using a smartphone on which the customer has installed the relevant Audi connect app.
The equipment and data specified in this document refer to the model range offered in Germany. Subject to change without notice; errors and omissions excepted.