BMW releases the sixth-generation eDrive technology, adopting the same cylindrical battery solution as Tesla

【PCauto】Recently, BMW Group held its “Technology Day” event in Landshut, Germany, where it officially unveiled its sixth-generation eDrive electric drive technology. The event’s most striking reveal was the introduction of a large cylindrical battery cell.

Since Tesla first showcased its 4680 large cylindrical battery in 2020, these cells have captured considerable attention in the battery technology sphere. Tesla’s early adoption of the technology secured it an initial lead in the electric vehicle market, drawing significant interest from battery manufacturers and automakers alike. However, following the initial enthusiasm, the number of firms dedicating deep research and development efforts to large cylindrical batteries dwindled, as the path to mass production proved challenging. Now, BMW has entered the field, with reports claiming that its large cylindrical battery cell has already outperformed Tesla’s 4680 in several key performance metrics and development potential.

In terms of cell size, BMW’s cylindrical battery maintains a diameter of 46mm but innovatively offers two height options—95mm and 120mm—tailored respectively for sedans and SUVs.

Regarding chemical composition, the BMW cell features an increased nickel content and a reduced cobalt level in its positive electrode, while the negative electrode is enhanced with additional silicon. This formulation boosts volumetric energy density by over 20%. On the charging front, the battery supports both 400V and 800V voltage platforms and, with a current capacity of up to 500 amperes, delivers significantly higher charging power, cutting charging time by more than 30%. Furthermore, its driving range has been extended by up to 30% compared to contemporary alternatives.

Despite BMW’s major breakthrough in large cylindrical battery technology, several challenges persist in achieving mass production. Critical obstacles include manufacturing bottlenecks—such as the welding techniques of battery tab, production line configuration, and the pace control of manufacturing processes—that must be overcome.

The inherent design of cylindrical lithium batteries necessitates a particularly delicate assembly of the positive and negative electrodes within the cell, and the challenge of managing internal heat dissipation can adversely affect battery longevity, resulting in a comparatively lower yield rate for large cylindrical cells. While Tesla’s 4680 battery has achieved a yield rate exceeding 95%, it still falls short of the 99% yield rate found in the 2170 small cylindrical battery.

To surmount these production challenges, BMW secured production demand contracts worth over 10 billion euros with two prominent Chinese battery suppliers, CATL and Eve Energy, when it unveiled its adoption of cylindrical cells in 2022. Moreover, BMW’s electrification R&D team has been diligently working to address manufacturing setbacks through continuous technological innovation.

By the end of 2024, BMW’s production base in Shenyang, China, had successfully initiated pilot production of its sixth-generation power battery project, with test batteries already delivered to the R&D team for rigorous evaluation. Pilot production of the first new-generation vehicle is also nearing completion, with expectations that BMW’s sixth-generation power battery will reach mass production in China by 2026.

In addition to the large cylindrical battery, the new sixth-generation eDrive system introduces a comprehensive upgrade to EESM (electrically excited synchronous motor) technology, while also incorporating ASMs (asynchronous motor) to further boost both performance and efficiency through an innovative motor combination.

Complementing these developments, BMW has unveiled the Energy Master—an intelligent central control unit located on the high-voltage battery. This unit offers interfaces for both high and low voltage power supplies and integrates data from the high-voltage battery, simultaneously managing the power supply for the electric motor and the vehicle’s electrical system to ensure safe and intelligent battery operation.

From an industry perspective, competition within the electric vehicle market is intensifying. Should large cylindrical batteries successfully overcome the hurdles to mass production, BMW stands to gain a distinct competitive edge in this rapidly evolving sector.