Musk has said before they monitor battery developments, but that he hasn't seen anything to catch his eye so far. Even Musk would be insane to switch the Gigafa

Musk has said before they monitor battery developments, but that he hasn't seen anything to catch his eye so far. Even Musk would be insane to switch the Gigafactory to a new, unproven battery chemistry. Plus, sodium-ion batteries are heavier than lithium-ion, so they're (probably) unsuitable for cars. Possible for Powerwalls though perhaps or a hypothetical Tesla truck where weight is less of a consideration.