okiedo:

I don't want get to nerdy on this topic but I have to outline one things:

Who ever works together with Tesla/ SolarCity has to apply its technology on a small cell standard (on purpose I am not calling it 18650 due to the fact that Tesla and Panasonic are moving away from this shape to a more "cyclindrical" form factor. The volume required by Tesla alone now allows to justify production changes that do not kill the economics of production.

Panasonic is upgrading old factories from lead acid and different form factor production to LI production to provide sufficient capacities (might this be something we recently heard about?) -> I will digg for further connections between Panasonic and EFL in production technology...

Pouch cell is often seen as the superior form factor - I strongly disagree - as this is often reduced on size and energy desity, but overlook production economics, thechnoloy modularity and technology implementation. When we think about the battery pack that Tesla uses as the foundation for EV enegry storage as well as stationary appliance for SolarCity, it makes sense to build an outer shell that includes management, cooling and security features and combine it with modular cells that can be changed and upgraded (or combined with other storage units, such as ultra caps (e.g. Maxwell K2). BTW: I think it is not an accident, that those two technologies get closer in their formafactors.

The large storage units which are already in use at super charger locations and in Freemont combine multiple of those 85KW packs (may be even 100KW in the same pack size - my idea, as this allows even better economics and Musk confirmed the ability to insert more cells into the pack).

Having build such a foundation allows Tesla to iterate in battery technology without questioning the EV platform (the skateboard), the essential part of their vehicle platfrom strategy.