Last year, the electric vehicle community’s attention was caught when Tesla battery researcher Jeff Dahn and his team published a paper revealing that quality lithium-ion batteries have the capability to last 1 million miles if used in EVs. A recent presentation from the respected battery pioneer has now revealed that these findings may actually be conservative, as the batteries that Dahn and his team have been testing are still going strong, and are now on track to pass the 2-million-mile mark.
Dahn’s updated findings were discussed in a recent video conference for energy storage and sustainable engineering. According to Dahn, the “million-mile” batteries that were referred to in the past year’s paper are now going towards 10,000 to 15,000 cycles. Considering that the million-mile cells were cycled 5,000 times, it is starting to become evident that the lithium-ion batteries that Dahn’s team have been testing have the potential capability to last 3.5 million km or over 2 million miles if used in an electric vehicle.
Remarkably, the lithium-ion cells that are being cycled by Dahn and his team have shown minimal degradation even at this point. With this in mind, there seems to be a good chance that even the study’s “2-million-mile” cells are capable of lasting even longer. Dahn notes that lithium-ion batteries have reached a point where it is becoming imperative to look into the further applications of advanced battery technology, such as vehicle-to-grid, or massive vehicles like airplanes and ferries.
As noted by the team in its 2019 paper, the lithium-ion batteries that it will be using are NMC532 pouch cells obtained from Li-FUN Technology in China. The NMC532 pouch cells are dry batteries as well, using no electrolytes. Interestingly enough, Tesla’s next-generation 4680 cells that the company revealed at Battery Day also utilize dry battery technology developed from the innovations of Maxwell Technologies, a company that the EV maker acquired.
Considering that the batteries which Dahn and his team are testing are just cells acquired from Li-FUN Technology in China, there seems to be a pretty good chance that Tesla’s next-generation 4680 cells could exhibit comparable or even superior performance when they are deployed to the company’s fleet of vehicles and energy storage units in the coming years. If these assumptions prove accurate, then Tesla’s next-generation cells may truly be a class above anything that is being used in the market today. Dahn, for his part, noted that Tesla’s battery strategy is sound.
“Tesla is just moving forward at the speed of light. They are upscaling their factories, they know they need Tera Watt Hours for both energy storage and vehicles, and it’s incredibly exciting times,” he said.
Watch Jeff Dahn’s recent talk about his team’s battery findings in the video below.