BMW has provided some initial insights into the development of high-voltage batteries and electric drive systems using its sixth-generation eDrive technology (Gen6 for short). These systems will go into every full electric Neue Klasse model, with the first one set to enter production later this year at the company’s Debrecen plant in Hungary.
According to the German carmaker, Gen6 batteries will see significant improvements such as a 30% faster charging speed and 30% increase in range. These will debut in the Neue Klasse and subsequently be used to drive models across the BMW Group’s fully electric product range, which should include MINI, as previously reported.
The Gen6 batteries are paired with an 800V electrical architecture and are said to have an even slimmer design, which enables integration into a wide range of models, regardless of vehicle height. Additionally, the battery packs will serve as a structural component in the bodies of Neue Klasse models (pack-to-open-body) and the new cylindrical cells will be integrated directly (cell-to-pack) in the housing of the high-voltage battery.
BMW didn’t provide the specifics of its cylindrical cells but it claims a 20% greater energy density when compared to the older Gen5 prismatic battery cell. The company also pointed out the Gen6 system will support bi-directional charging as standard.
The high-voltage batteries will be assembled in five new production facilities located in Irlbach-Straßkirchen (Lower Bavaria), Debrecen (Hungary), Shenyang (China), San Luis Potosí (Mexico) and Woodruff, near Spartanburg (USA).
To manage energy flow, there’s the BMW Energy Master, which is a central control unit positioned on the high-voltage battery to provide the interface for high- and low-voltage power supply, while also managing the power supply for the electric motor and vehicle electrical system. The Energy Master was developed fully in-house and will benefit from technological developments and updates that can be implemented independently and in real time via remote software upgrades.
As for the electric motors, BMW is keeping to electrically excited synchronous motor (EESM) for its Gen6 power unit. On this type of motor, the magnetic field in the rotor is generated by windings fed with direct current rather than permanent magnets. Much like Gen5 drive systems, the EESM will be positioned above the rear axle and features a compact housing incorporating the electric drive unit, power electronics and transmission.
Improvements for the Gen6 EESM include a fully redesigned rotor, stator and inverter to suit the 800V architecture. Additionally, the oil and water cooling systems have also been reworked, while the motor and central housing are improved in terms of their weight and rigidity.
The transmission keeps to a two-stage helical design but with further optimisations to enhance its geometry and cooling, lower friction levels and more pleasant acoustics. The inverter too gets reworked for 800V technology and gets silicon carbide (SiC) semiconductors to boost efficiency.
For models with xDrive, the Gen6 powertrain adds an asynchronous motor (ASM) on the front axle that is said to be more compact and cost efficient. Instead of being generated by permanent magnets (PSM) or electrical excitation (EESM), the ASM’s rotor’s magnetic field is induced by the stator instead, with the rotor taking the form of a metal cage.
Looking to sell your car? Sell it with Carro.
