Originally, the cells were announced at the Tesla Battery Day in September 2020 with a promise to significantly reduce costs and increase energy density (by 30% even without new chemistry) in combination with structural battery packs.
Tesla currently uses much smaller, 2170 cylindrical cells in Model 3/Model Y and 1865 cylindrical cells in Model S/Model Y.
According to the company, substantial progress has been made, including:
- successfully validated performance and lifetime of 4680 cells
- the company is nearing the end of manufacturing validation:
- field quality and yield are at viable levels
- focus is now on improving the 10% of manufacturing processes that currently bottleneck production output
In other words, the cells work fine and the overall manufacturing approach is viable, but there are bottlenecks that prevent volume production required to produce EVs in volume.
"We have successfully validated performance and lifetime of our 4680 cells produced at our Kato facility in California. We are nearing the end of manufacturing validation at Kato: field quality and yield are at viable levels and our focus is now on improving the 10% of manufacturing processes that currently bottleneck production output. While substantial progress has been made, we still have work ahead of us before we can achieve volume production."
Let's recall that in late April, Tesla's CEO Elon Musk said that volume production is about 12 months away (not more than 18 months). That would be May 2022 at best.
This is crucial for the launch of the new Tesla Model Y with 4680 battery cells and structural battery packs in 2021 both in Austin and in Berlin. Tesla races with time to at least start with a few GWh of annual output.
20,000 EVs with a 75 kWh battery each, means 1,500 MWh (1.5 GWh) of battery cells.
The Tesla Semi program was already delayed until 2022, probably mainly due to the constraints of 4680 battery cells. The fate of the Tesla Cybertruck might be similar (the plan is to introduce it after the Model Y, in Austin).
Separate, positive news is that the new structural pack architecture (with the new 4680 cells, we assume), and a single-piece front casting passed internal tests:
"Internal crash testing of our structural pack architecture with a single-piece front casting has been successful."