Audi Q8 e-tron battery

The battery on the Audi Q8 e-tron is available in two different sizes. 95kWh and 114kWh gross.

Cell technology

Audi/Volkswagen has a multi-vendor strategy on cells. That means that Audi uses different vendors of Lithium-ion cells for various batteries.

Battery packs

114kWh battery pack

The battery for the Audi SQ8 e-tron and Audi Q8 e-tron has a gross capacity of 114kWh (106kWh net) and a nominal voltage of 396 volts. It consists of 36 modules with 12 cells each, which gives a total of 432. The cells in each module are connected in a 4p3s configuration. Meaning 4 and 4 cells are grouped in parallel and then connected in serial.

Since each cell is on 72ah, each parallel group gives a capacity of 288Ah. (4 x 72ah)

When 36 modules like this are connected in serial the nominal voltage is 396 volt.

396volt * 288ah = 114 048 Watt-hour (Wh) or 114kWh (kilo Watt Hours)

Each module is on 11 Volt and has a capacity of 288 x 11 = 3168 Wh or 3.168 kWh.

Each module weighs approx 13kg.

Total battery weight is 1605lb (728 kg)

95kWh battery

The battery for the Audi Q8 50 e-tron has a gross capacity of 95kWh (89kWh net) and a nominal voltage of 396 volts. It consists of 36 modules with 12 cells each, which gives a total of 432. The cells in each module are connected in a 4p3s configuration. Meaning 4 and 4 cells are grouped in parallel and then connected in serial.

Since each cell is on 60ah, each parallel group gives a capacity of 240Ah. (4 x 60ah)

When 36 modules like this are connected in serial the nominal voltage is 396 volt.

396volt * 240ah = 95 040 Watt-hour (Wh) or 95kWh (kilo Watt Hours)

Each module is on 11 Volt and has a capacity of 240 x 11 = 2640 Wh or 2.64 kWh.

Each module weighs approx 13kg.

Total battery weight is 1532.2lb (699,99 kg)

Battery housing

Most of the battery housing parts are reused with the larger 95kWh battery. The 95kWh uses a second floor under the rear seats to get the room needed for the 36 modules.

Sophisticated measures have been taken to protect the high-voltage battery of the Audi etron. A strong enclosing frame of cast aluminum nodes and extruded sections, plus an aluminum plate 3.5 millimeters (0.1 in) thick protect against damage from accidents or curbs. Inside, a framework-like aluminum structure reinforces the battery system. Also comprised of extruded sections, it holds the cell modules like a typecase.

Including the housing with its sophisticated crash structures comprising 47 percent extruded aluminum sections, 36 percent aluminum sheet, and 17 percent diecast aluminum parts, the battery system weighs around 700 kilograms (1,543.2 lb). It is bolted to the body structure of the Audi e-tron at 35 points. This increases its torsional rigidity by 27 percent and contributes to the high level of the safety of the Audi e-tron, as does the cooling system bonded to the outside of the battery housing. Compared to a conventional SUV, the Audi e-tron offers 45 percent higher torsional rigidity, a key parameter for precise handling and acoustic comfort.

Thermal management

The battery packs are created to give high performance over a large range of temperature and charge levels.

A cooling system of flat aluminum extruded sections divided uniformly into small chambers has the task of maintaining the battery’s high-performance operation over the long term.

Heat is exchanged between the cells and the cooling system beneath them via a thermally conductive gel pressed beneath each cell module. In what is a particularly efficient solution, the gel evenly transfers the waste heat to the coolant via the battery housing.

The battery and all of its parameters, such as charge status, power output, and thermal management, are managed by the external battery management controller (BMC). This is located in the occupant cell on the right A-pillar of the Audi e-tron. The BMC communicates both with the control units of the electric motors and the cell module controllers (CMC), each of which monitors the current, voltage, and temperature of the modules.

The battery junction box (BJB), into which the high-voltage relays and fuses are integrated, is the electrical interface to the vehicle. Enclosed in a die-cast aluminum housing, it is located in the front section of the battery system. Data exchange between the BMC, the CMCs, and the BJB is via a separate bus system.

Charging performance

Audi e-tron has been market-leading in average charging speed since its introduction. So how does this compare to the facelift? Together with EVKX.net, electrichasgoneaudi.net gives you the details. Below is the charging curve for Audi Q8 50 e-tron (same as the Audi e-tron 55) and the Audi Q8 e-tron 55 with the new battery.

As the table shows, the 95kWh battery is still comparable to the new battery and even beats the larger battery because of a flatter curve for this distance.