During a call with investors after the company’s earnings report, Elon Musk mentioned that the Model S and X might soon get a battery upgrade.
Specifically, someone asked the CEO if the Model S and Model X would ever get an upgrade to the same type of battery as the Model 3.
In reply, Musk stated that the company has actually improved the battery chemistry in the Model S a few times. He furthered this by saying that Telsa has actually improved it recently and that the maximum range of the car is closer to 380 miles (611km) than the (373 miles) (600km) advertised.
There’s no further mention of when users can expect the full 400 miles (643km) or if this is even something that the company can for sure pull off. Since it was mentioned in an earnings call, it could all just be speculation.