Battery swapping has a number of disadvantages: forcing all the cars to use a specific size and shape battery, which may not be great for packaging efficiency.

Battery swapping has a number of disadvantages: forcing all the cars to use a specific size and shape battery, which may not be great for packaging efficiency. Battery has to be physically more robust to be able to withstand regular handling. It has to be designed to be quickly detachable, because if the battery takes 20 minutes to take out, it's definitely not faster than just charging the thing.