Posted on November 15, 2016 by Matt Pressman
With Tesla Motors [NASDAQ; TSLA] transitioning from Panasonic's 18650 lithium-ion battery to the Gigafactory's newer 2170 battery designed for the Tesla Model 3, observers have wondered whether significant battery improvements might be in the works. Electrek* reports: "at the National Entrepreneur Week in Mexico, Tesla [Co-Founder and] CTO JB Straubel elaborated on the improvements made in battery technology and quantified it – saying that Tesla has seen a 30% improvement in energy density between the Model S and Model 3."
Above: Tesla Model 3 (Instagram: @pjmccartney)
What did Tesla's CTO say during the presentation? Straubel explained, "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."
Above: Tesla Model 3 on display at a recent Tesla staff event at Avaya stadium (Instagram: @formulaphotography)
How did Tesla achieve this? Straubel explains that the path to lowering battery costs can also yield improved energy density: "One of the not very intuitive, maybe not common sense pieces of this is that as you increase the energy density of the battery, you are also reducing the cost. Because in really high volume, things tend to cost about the same as they weigh. You can essentially look at the raw materials that go into the battery and how much those weigh – and that tends to be what define the cost. So if you want to reduce the cost, the best way to do that is to use fewer materials. And if you do that, you just increased energy density. That’s a key feedback that is very helpful and it is actually happening."
Above: Tesla CTO JB Straubel speaks - starting at 6 min 3 sec - during National Entrepreneur Week in Mexico (Youtube: Ef3 Kay)
Electrek reports that the first consumer vehicle application with "this 30% [energy density] improvement will be seen in the Model 3," per Straubel. That said, it will be interesting to see what battery pack options will ultimately be available for the Model 3. It turns out that, "Tesla’s Vice-President of Investor Relations, Jeff Evanson, previously said that the base version with 'more than 215 miles of range' will be equipped with a battery pack 'smaller than 60 kWh', but we do know that better options will also be available." We're looking forward to learning more soon.