"400 Wh/kg *with* high cycle life, produced in volume (not just a lab) is not far. Probably 3 to 4 years," Musk tweeted on Monday ahead of its anticipated "Battery Day" event where Tesla is expected to reveal how it has improved its battery performance.
400 Wh/kg *with* high cycle life, produced in volume (not just a lab) is not far. Probably 3 to 4 years.— Elon Musk (@elonmusk) August 24, 2020
Researchers have said the energy density of Panasonic's "2170" batteries used in Tesla's Model 3 is around 260Wh/kg, meaning a 50% jump from the current energy density which is key to achieving a longer driving range.
Tesla said its Battery Day will take place on the same day as its 2020 annual meeting of shareholders on Sept. 22.
South Korean battery expert Park Chul-wan said the image may hint at "silicon nanowire anode," a breakthrough technology which can potentially increase both battery energy density and battery life sharply.
Panasonic Corp earlier told Reuters that it plans to boost the energy density of the original "2170" battery cells it supplies to Tesla by 20% in five years.
Tesla is also working with China's Contemporary Amperex Technology Ltd (CATL) to introduce a new low-cost, long-life battery in its Model 3 sedan in China later this year or early next year, with the batteries designed to last for a million miles of use, Reuters reported in May.
A very "limited number of stockholders" will be able to attend the Sept. 22 events due to pandemic-related restrictions, Tesla said, and a lottery will be held to select attendees.