10-15 years ago, 400 Wh/kg would be considered as a Holy Grail. Now it's clearly on the horizon, according to Elon Musk.

Tesla's boss Elon Musk in one of his latest tweets has hinted that high-energy dense battery cells (level of 400 Wh/kg) with "high cycle life" and "produced in volume", are not far away.

He expects those kinds of batteries on the market in 2023-2024: "Probably 3 to 4 years." Previously we heard about such a high level of energy density only on a lab-level or in ultra-low scale production for special application at a prohibitive cost and with serious issues of low cycle life/low power.

His tweet was a direct response to one of the followers, who asked about electric jet and relation to Amprius, a company engaged in silicon nanowire anodes, which moved its HQ right next to Tesla's 'Roadrunner' facility.

 

The 400 Wh/kg level would be 54% higher than roughly 260 Wh/kg that Tesla is using today.

EVs would not weigh that much then, even when having huge battery packs:

  • 75 kWh battery at 400 Wh/kg: 188 kg of cells (compared to 288 kg now)
  • 100 kWh battery at 400 Wh/kg: 250 kg of cells (compared to 384 kg now)
  • 150 kWh battery at 400 Wh/kg: 375 kg of cells (compared to 577 kg now)
  • 200 kWh battery at 400 Wh/kg: 500 kg of cells (compared to 770 kg now)

We should know more about the perspective at the upcoming Battery Day, scheduled on September 22, 2020.

According to Tesla, only a limited number of stockholders will be able to attend the event because of COVID-19 related restrictions.

An interesting thing is the lead image at Tesla's website, which might suggest the electrode material structure under the microscope:

Tesla 2020 Annual Meeting of Stockholders and Battery Day
Tesla 2020 Annual Meeting of Stockholders and Battery Day

Separately, the currently used Tesla batteries - manufactured by Panasonic - are expected to gain 5% energy density later this year, and 20% within 5-years.

Source: Reuters