VW may beat Tesla to its cheaper 4680 battery promise thanks to a storied German printing company
Tesla's Battery Day 2020 promise that 4680 cells will be 50% cheaper to manufacture than other battery designs hasn't yet materialized. Tesla already walked the easy 4680 battery cost cut path by introducing the structural pack on the Texas-made Model Y.
There, the 4680 cells are integrated as a structural part of the chassis by the virtue of their size, reducing packaging, connectors, and welding spots needed dramatically, for a greatly improved volumetric density. The energy density of Tesla's 4680 cells themselves, however, is virtually the same as that of the 2170 batteries it uses in the Model Y made elsewhere.
By introducing the 4680 structural battery pack design changes, Tesla has reportedly cut its production costs by about 20%. To shave off the other 30% needed to fulfil its Battery Day promise, however, Tesla needs to leverage the dry electrode coating production method it acquired from Maxwell back in 2019. Instead of the expensive wet coating that the 4680 electrodes are produced with now, which involves a lot of toxic solvents and baking of cathodes to dry them up, the dry coating method is cleaner and much less energy-intensive, plus it requires smaller production facilities.
While Tesla currently has a problem to scale the dry electrode coating method for mass production, one surprise announcement by Volkswagen could hold the key to cheaper and more sustainable batteries. VW has partnered with a storied German printing company - Koenig & Bauer - to develop equipment for layering cathode materials in a powder form without the use of the toxic solvents involved in the wet production method.
Koenig & Bauer will leverage the industrial printing knowledge acquired since it was founded back in 1817to apply an ultrathin even layer of dry battery material powder on the electrode foil. Besides being a much cheaper method than wet coating, this would eventually lead to uniform spatial energy density and allow for faster charging of the batteries produced with it.
According to Volkswagen's battery subsidiary PowerCo, the printed dry electrode production method would cut its battery pack costs by millions of euros as it needs 30% less energy and 15% smaller production facilities, not to mention eschewing the toxic chemicals that are now used for the purpose. While it doesn't become clear if VW's dry coating will reduce the battery costs by 30% in total, or exactly the walk that Tesla needs to cover to reach the 50% manufacturing expense reduction that it said 4680 cells would lead to, VW will have exclusive rights to the printing equipment needed for the dry method.
Koenig & Bauer will continue the work throughout next year and, if successful, VW's exclusivity over this dry electrode coating application will run for 7 years, during which other battery makers will be trying to catch up by developing or copying their own take on this promising technology for EV battery cost reduction.