Practically it could work out very well.<p>The Big Three might voluntarily standardize on a battery formfactor and swapping bay, because it would put them ahead of Tesla.  &quot;Our patent is free, follow our lead Mr Musk.&quot;<p>There could still be plenty of flexibility in shape, but it would likely be constrained.  Like, the width&#x2F;depth must be a fixed number of centimeters, and there must be a common connector and common mounting points.  But the length is up to the manufacturer, programmed into an RFID tag for the swapping bay.  (And you&#x27;d be able to use shorter batteries inside a larger vehicle.)<p>Battery advances are the most trivial of all to incorporate.  Already li-ion packs require dedicated charging circuitry.  The exact cells used don&#x27;t matter, a tenth-of-a-cent EEPROM is programmed with the charging curves of the cell chemistry.<p>If anything battery tech will advance much faster with swapping.  Without swapping you have to be very conservative.  Advances can only be introduced with new models (so once a year) and are very costly to get wrong across a fleet.  With swapping you could put a couple of prototypes into the pool every month, and swap them out immediately if the prototype underperforms.