The main argument against this is that Elon said the 3k production target in GF3 is only 10% of the end goal. So Tesla would spend money redesigning battery packs for all their vehicles for a subset of Chinese production.I know that @KarenRei disapproves of 18,650 vs. 21,700 discussions, but my take is the following:
So I believe the conclusion is obvious: if Panasonic's Japan 18,650 output could be reconfigured to make 21,700 cells in a relatively low capex fashion, then that could form the basis for the initial Model 3 production in China. There would be no tariffs, and Japan->China transportation costs are lower as well as Japan->U.S. or U.S.->China.
- There's been persistent and credible seeming speculation that Panasonic's 18,650 lines in their Japanese factories could be converted over to the 21,700 cell format: a large percentage of equipment is cell format agnostic, and most of the format specific machines apparently can 'just about' accommodate the 21,700 format.
- It seems unlikely in the extreme to me that Panasonic would build 35 GWh/year 21,700 capacity without having a good forward plan for the 18,650 equipment - especially that 'closing factories and firing employees' is a social taboo in Japan.
- Panasonic's 18,650 manufacturing capacity in Japan is about 8 GWh/year.
- The Shanghai Gigafactory will only make Standard Range Model 3's.
- The Standard Range Model 3 will come with a ~50-55 kWh battery, which means 8 GWh/year supply is enough for 2800-3100 Model 3's at Shanghai.
- The targeted capacity of the Shanghai factory happens to be 3000 cars/week, matching the available cell supply in Japan very well ...
But, obviously, this is probably under negotiation, and Panasonic would have to commit to this plan - and I bet Tesla wants a price reduction as well - they could after all probably buy cells on the Chinese market as well.
All of this is speculation only of course.
I still think the medium term outcome is a full shift to 21700 cells once there is a decent refresh of the S and X. The Japanese factories can retool at this point .