Powertrain
Rear wheel drive (RWD) models make use of a water-cooled brushless permanently excited synchronous motor positioned along the rear axle, producing up to 150 kW of power and 310 Nm of torque and rotates at a speed of up to 16,000 rpm. The motor is coupled to a 1-speed transmission with a fixed gear ratio of 13:1 and typically operates with "substantially greater than 90 percent" efficiency.
The motor, transmission, and power electronics (DC/AC converter) together form a compact drive unit that weighs around 90 kg.
For the all-wheel drive quattro model, a further asynchronous motor is positioned at the front axle, providing an additional up to 75 kW of power at a speed of 14,000 rpm when required. In most situations, the front motor is not activated in order to increase overall efficiency. Its 1-speed gear is fixed at a ratio of 10:1 while the rear motor in AWD models operates at a ratio of 11.5:1.
During braking, the rear-wheel drive models can recuperate energy up to forces of 0.15 g and up to 0.3 g in the all-wheel drive models, which equates to up to 145 kW of power. When driving, the vehicle by default is set to coast, with recuperation up to 0.15 g being optional.[15]
The motors rotor and stator are produced at the Volkswagen Group Components plant in Salzgitter and are assembled in Kassel, where the 1-speed transmission is built as well. For the Chinese market, the electric drive components are produced in Tianjin.
Battery
The battery consists of a liquid-cooled Lithium-Ion battery pack which houses either 10 or 12 modules containing the individual battery cells in an aluminium casing. The smaller battery holds an energy content of 55/52 kWh, while the larger pack comes in at 82/77 kWh and weights of 350 kg and 500 kg, respectively.
Whereas the battery system is assembled at Volkswagen Group plants, the Nickel-Manganese-Cobalt (NMC) battery cells are obtained from suppliers such as LG Energy Solution and CATL. For the Zwickau plant, battery cells pre-assembled into modules at LGs Wrocław plant are delivered by train to be assembled into batteries in Braunschweig.[16]
If charged at a public DC fast charger at a rate of 125 kW under ideal conditions, Audi claims that the 82/77 kWh battery pack can charge from 5 to 80 percent in 38 minutes.[15]
Audi Q4 e-tron
