As Tesla’s battery day approaches, Musk hints at significant capacity growth.

Tesla’s much-anticipated battery day comes after CEO Elon Musk shared some insights on energy density via Twitter,media reported. Responding to a question about the possibility of electric aircraft, Musk said that in the next three to four years, 400 watt-hours per kilogram of batteries are highly likely to appear, and that they will be disposable batteries, but will have batteries that can be mass produced.

As Tesla's battery day approaches, Musk hints at significant capacity growth.

This type of energy density provides 50 percent more energy density than current batteries, which are known to be about 260 Wh/kg used by Tesla Model 3. The more energy stored in the battery, the longer the car’s mileage.

Musk’s comments were accompanied by a preview of a special pattern with many dots. Reuters reported that the model could herald the emergence of silicon nanowit anodes, which, if implemented, could help Tesla build more energy-dense, longer-life batteries. Tesla did not immediately respond to a request for comment.

As Tesla's battery day approaches, Musk hints at significant capacity growth.

This year’s news about Tesla’s batteries has been rife with speculation. From Panasonic’s promise to increase energy density over the next few years to China’s CATL’s partnership with Tesla on “million-mile” batteries, energy-related news is never lacking. Earlier this year, Tesla also applied to become a utility provider in the UK.

With less than a month to go until Battery Day, which begins on September 22, it is believed that more news will be heard.