Tesla has published an 11,000-page document in which it outlines Giga Berlin's 4680 battery cell production process.

While certain parts of Tesla's document are blacked-out, it's still very interesting on how Tesla explains the 4680 battery cell production process at Giga Berlin. What is particularly interesting is that the finished 4680 cells would be subjected to 10 days’ worth of curing after their formation.

In its planned battery factory, Tesla wants to produce lithium-ion cells for 500,000 vehicles with a capacity of 50 gigawatt-hours per year in the first expansion phase. This emerges from the new, extensive application documents that have been available to the public for inspection since June 18, 2021. Several media reported on this, including the Lausitzer Rundschau and the Potsdamer Neuesten Nachrichten.

Tesla CEO Elon Musk announced in November 2020 that he wanted to turn the future plant of the electric car manufacturer near Berlin into the world's largest battery factory. The changes in the ongoing approval process were necessary due to this planned expansion, among other things.

Most importantly, Tesla also submitted a simplified diagram of its 4680 battery cell production process, Here is the Tesla Giga Berlin battery plant's brief overview.

“The battery the Gigafactory Berlin requires special systems and process steps. The anodes and cathodes consist of coated current collector foils. Copper is used as the material for the anode foil and aluminum is used for the cathode foil. The anode and cathode components are manufactured in mixed processes (A020-01 and A020-02), which only use materials in powder form. The new materials used are tested and approved in our own laboratory (A020-11).

“In order for the powder coating to adhere to the two films, they must first be pre-coated with a thin layer of adhesive (substrate) (A020-03 and A020-04). This substrate is delivered in containers. The pre-coating is necessary because a dry coating with powder takes place. After the anode and cathode components have been mixed, they are applied as a coating to the respective substrate-coated film in order to establish electrical contact (A020-05 and A020-06). The current collector foils, coated with the anode or cathode components, result in the finished anode or cathode.

Giga Berlin's revised filings also provided a general idea of how Tesla’s tabless cell production works. Among these is the fact that the finished 4680 cells would be subjected to 10 days’ worth of curing after their formation.

“The anode or cathode is then cut to the required lengths with a laser in the “tabless process” (A020-08). The anode, the cathode and the separator are alternately placed one on top of the other and rolled up into a roll. This roller is then inserted into a metal housing, which is manufactured from steel rollers in a die-cutting and deep-drawing process (A020-07). In the assembly area, the final assembly and filling of the cell takes place with small amounts of electrolyte (approx. 10% of the cell weight) (A020-09).

“The electrolyte is absorbed by the electrode coatings and enables the lithium ions to move back and forth between the anode and cathode. The housing is then closed with a lid in a welding process. The last step is the formation (A020-10) of the cell. In the formation process, the cell is electrically started up by charging and discharging it under different temperature conditions. The finished cell remains in this area for approx. 10 days and is then put to further use. The cells produced are subjected to random quality control in our own laboratory (A020-11).”

#Tesla
#Tesla4680BatteryProduction
#GigaBerlin

This is Armen Hareyan from Torque News. Please follow us at https://twitter.com/torquenewsauto on Twitter and https://www.torquenews.com/ for daily automotive news.

Reference
https://www.uvp-verbund.de/trefferanzeige?docuuid=94AFADF0-92F1-44EA-AA54-E1CD7C0FF6AD
https://www.teslarati.com/tesla-4680-battery-factory-details-giga-berlin-revealed/