Posted on 27 Dec 2023
Tesla is reportedly still having trouble producing 4680 battery cells at its gigafactory in Austin, Texas, after problems were identified in the dry-coating process.
According to several sources who spoke with Reuters, Tesla is not yet dry-coating the 4680 cells at the scale needed to hit production targets. The unnamed sources noted that while dry-coating the cell’s anode did not create any problems, the manufacturer is struggling to apply the same technique to the cathode.
The 4680 batteries – which are now planned for the Cybertruck model – each reportedly include an estimated 1,360 individual cells. According to Reuters’ calculations using unpublished data, the company’s Giga Texas factory takes about 16 weeks to produce 10 million of the cells.
However, this capacity equates to Tesla producing 32.5 million cells a year – just enough to power about 24,000 Cybertrucks. Kallanish notes this could create problems for Tesla as it looks to ramp-up Cybertruck production to 250,000 vehicles/year by 2025.
As of October, Tesla was producing 4680 cells on two production lines at Giga Texas. It plans to install eight total lines at the gigafactory, with the final four lines expected to become operational late next year. However, those lines come with a learning curve.
According to the report, roughly 5% of cells made on profitable production lines are scrapped. When each new line becomes operational, those scrap rates could allegedly increase to 30-50% and remain elevated for several months.
Additionally, sources claim that Tesla is finding it difficult to mix cathode materials with a binder and attach them to the metallic foil used to produce cathodes without a liquid. While the process reportedly worked at a smaller scale, it generated a great deal of heat when scaled up.
The report also outlined problems around the machines Tesla uses to coat that metallic foil. The company is said to be trying to coat several strips of foil with active battery materials at the same time, and at a very high speed.
However, that process uses roller equipment to firmly press the materials onto the foil. The process uses a lot of force and if that pressure is not evenly applied, the product may warp and become unusable.
Tesla has not replied to Kallanish’s request for comment.
In early 2023, the EV manufacturer announced it would build a 100-gigawatt-hour new factory to produce 4680 cells at Giga Nevada. Panasonic, a Tesla supplier, said in 2021 it could produce 4680 cells more efficiently than its peers.
Source:Kallanish
