That's according to Tesla, who made the claim in connection to cells in electric cars yesterday in its Q1 2018 shareholder letter.

Unfortunately, Tesla's statement includes no hard numbers, so it's not like we can compare the energy density of the Model 3 cells to other electric cars out there. This methodology of making a claim with no backing is quite typical in the battery cell biz and is actually a path often taken by Tesla is other areas too, including car safety claims.

Tesla Q1 2018 Earnings Call Overload

So, we wouldn't put too much faith in this statement, but here it is, regardless:

"The Model 3 battery has sophisticated power electronics, cooling systems and structure that enables high level of safety, sports-car like acceleration, Supercharging, a 120,000 mile warranty and low cost. Cells used in Model 3 are the highest energy density cells used in any electric vehicle. We have achieved this by significantly reducing cobalt content per battery pack while increasing nickel content and still maintaining superior thermal stability. The cobalt content of our Nickel-Cobalt-Aluminum cathode chemistry is already lower than next-generation cathodes that will be made by other cell producers with a Nickel-Manganese-Cobalt ratio of 8:1:1. As a result, even with its battery, the gross weight of Model 3 is on par with its gasoline-powered counterparts."

The most recent Tesla Model 3 battery cell energy density statement from Tesla came when CTO J.B Straubel spoke at a conference in 2016. he stated:

“These batteries are steadily improving every single year – maybe around 5% improvement in their energy density their ability to store energy in a given amount of mass. That’s probably one of the key metrics we worry about. And when we went from the Roadster to the Model S, they have improved by about 40% and when we were designing the Model 3, they were about another 30% better. That improvement just continues on every single year in the background.”

Again, no hard numbers there. Just percent improvements. But teardowns provide us with additional details, if they're accurate, that is. From a 2107 Model S teardown:

Modules presented are:

  • 444 cells (74 parallel and 6 series)
  • 5.3 kWh, 24 V
  • 56.45 lbs (25.6 kg) -> 207 Wh/kg
It's a starting point.