“The driver sits on top of up to 8000+ thermodynamically unstable lithium battery cells (18650’s)”
2 – Cost: The manufacturing time and materials required for the 4680 means productions costs will drop by 56%. We are going to see real competition on the raw sticker price in the window at the local car dealer. Currently, 4,416 (Model 2170 lithium ion) cells are placed inside a Tesla Model 3 or Model Y long-range edition battery packs. In contrast, only 960 cells will be required to fill the same space with the new 4680 Dry-Cell. As an added bonus, Tesla won’t have cobalt in their batteries anymore, that means no more memes about children in the Congo!
https://fcpp.org/2020/12/26/the-tesla-4680-battery-six-things-to-know/
I am happy about all of that. I am NOT anti-Tesla and think as a company they are on the cutting edge of managing or harnessing the potential of the current battery chemistries.
However, I think the Tesla semi is a bad application of the technology based on risk/benefit analysis (2 - 4000# packs is a LOT of potential for something to go wrong compared to a single 1100# pack in a sedan for example). I also think their new truck is an excessive use of resources for the designed purpose but I expect we will see fewer “fires” with them than they had with the Nikolei (sp?) trucks in Phoenix (believe they had 4 burn out of 280 made or something like that).
Another advantage to the larger 4680 cells is that (I hope) they may be able to connect each individual cell to the battery management system instead of entire rows. This is another limiting factor for EV’s because one bad cell causes the BMS to isolate and turn off a row of 50 or 100 batteries (18650 or 2170) leading to a more significant loss of range/capacity and shorter battery life. Monitoring each individual cell might also reduce the chance of that cell going into thermal runaway if it is acting up.