BMW Gen6 Battery System

At the moment the details are sketchy for the BMW Gen6 Battery System, but we will gradually piece together what we can. The plan is that this battery design will launch in 2025 in the Neue Klasse EVs.

Round cells are being used for the first time in the sixth generation of electric mobility batteries from the BMW Group. With a diameter of 46 millimetres and two different heights of 95 and 120 millimetres, the new cells are a perfect match for the completely redesigned and exclusively all-electric Neue Klasse architecture. The storage system takes on a supporting role in the body structure and, depending on the model, can be integrated flexibly and in a space-saving manner in the installation space.

ROUND BATTERY CELLS FOR THE NEUE KLASSE, BMW Group

Tesla have adopted the 4680 cell format. Based on a range of key improvements that this brings:

• lower cost
• higher energy density
• lower manufacturing costs

The BMW Gen6 battery is also a push to lower costs and improved energy density. Initially the cells will have NMC chemistry and will be manufactured by BMW’s existing partners CATL and EVE.

The BMW goals are [1]:

• lower cost
• improve energy density
• reduce charging time
• reduced manufacturing emissions

Cell Specifications

• Chemistry
  • NMC
    • high Nickel content
    • low Cobalt content
  • Anode
    • increasing silicon content

the first outing for the Tesla 4680 is without Silicon in the anode, this might be a move to reduce costs, reduce the cell expansion or to present a strong energy uplift roadmap for the vehicle

• 4695:
  • Nominal energy: 120 to 140Wh
  • Mass: ~0.42kg
  • Diameter: 46mm
  • Height: 95mm

This lower height cell will have been selected for use in saloon / crossover type vehicles. However, this is not as easy to fit under the traditional saloon design as the 70mm high 21700. So expect this to be more of the “jacked up” design like the Model Y.

The EVE cylindrical cell INR46950 is close to the 4695 specification, however, it is 96.5mm tall rather than 95mm.

• 46120
  • Nominal energy: 148 to 180Wh
  • Mass: ~0.53kg
  • Diameter: 46mm
  • Height: 120mm

The 120mm high cell is definitely for the larger SUV’s as this will result in a battery pack height of around 155 to 170mm at best.

Pack Design

• Pack to Open Body Design
  • new battery pack does not contain battery modules

BMW’s “pack to open body” design hints at a body and battery structure designed to fully work together. To do this it is necessary to also look at the manufacturing process and flow.

The battery system plays a key role in the body structure of the NEUE KLASSE. Depending on the model, it can be flexibly integrated into the installation space to save space (“pack to open body”). The cell module level is thus eliminated.

BMW Group to use innovative round BMW battery cells in NEUE KLASSE from 2025, BMW Group Press Club

95mm tall cells will still be a significant packaging challenge for a saloon car, it will be interesting to see the design for the cell to cell busbars, cooling and cell venting.

• 800V system
  • enables 350kW fast charge
  • up to 500A fast charge
  • reduces inverter and motor losses

• 20% increase in energy density

this should put the new BMW EV’s above 200Wh/kg at pack level

• 30% improvement in fast charge time

This should put BMW in amongst the ~20 minutes for the 10 to 80%, however, this really depends on the chemistry, cell design and pack thermal design. It would be good to understand what cooling system they are going to use with this 46xx cell.

• 50% cost reduction at pack level [2]

Manufacturing

• six new factories to be built around world with its partners CATL and EVE
  • in addition the five existing factories
  • 20GWh of batteries per factory per year
• CO2 production reduction goal of 60%
  • increased percentage recycled materials for the lithium, cobalt and nickel
  • green power during production
• BMW aims to make its battery manufacture completely circular
  • this is a challenge for the recycling and quality of the recycled materials
  • logistics and inventory of recovering

References:

1. BMW Plans EV Battery Dominance With New Gen6 Cylindrical Cell, Forbes, James Morris
2. BMW To Use Round Battery Cells, 6 Gigafactories Confirmed, InsideEVs
3. BMW Group to use innovative round BMW battery cells in NEUE KLASSE from 2025, BMW Group Press Club
4. ROUND BATTERY CELLS FOR THE NEUE KLASSE, BMW Group