Tesla unveiled plans Tuesday to develop a “tabless” battery that could improve an electric car’s range and power. The company will produce its new batteries in-house, which Tesla CEO Elon Musk predicts will help dramatically reduce costs and allow the company to eventually sell electric vehicles for the same price as gasoline-powered ones.
The battery is expected to lower Tesla’s cost per kilowatt-hour, the unit of energy most commonly used to measure the capacity of the battery packs in modern electric vehicles. Many experts believe that lowering these costs would allow Tesla to dramatically lower the price of its cars, thereby making them far more accessible. The news of the new battery was announced during the company’s much-hyped “Battery Day” event in Palo Alto, California.
Musk said Tesla achieved this breakthrough by removing the tab, a part of the battery that forms a connection between the cell and what it is powering. These new tabless cells, which Tesla is calling 4680 cells, will give the company’s EV batteries five times more energy capacity, make them six times more powerful, and enable a 16 percent range increase for Tesla’s vehicles. The tabless cells were among the first announcements from Tesla’s Battery Day.
The new cells are bigger than Tesla’s current cells, measuring 46 millimeters by 80 millimeters (thus the name, 4680). In addition to more energy and power, the new cells will result in a 14 percent reduction in cost per kWh at the cell form factor level only, Musk said. Tesla’s new cell manufacturing system is “close to working” at the pilot plant level.
During the event, Drew Baglino, Tesla’s vice president for powertrain and energy, offered more insight into the new cells. He said that Tesla’s engineers “laser patterned” the existing foils in the cell to create a “shingled spiral” that results in a shorter electrical path length of 50 mm, versus the existing 250 mm length in the current cells.
“You actually have a shorter path length [for the electron to travel] in a large tabless cell than you have in the smaller cell with tabs,” Musk added. “So even though the cell is bigger, it actually has more power.”
Like most car companies, Tesla sources its batteries from major producers so it can focus on its core mission: building electric cars. The company’s 2170 cells, which are currently used in Model 3 and Model Y vehicles, are produced by Panasonic at Tesla’s Gigafactory in Nevada.
But those supplies have become strained. In 2018, a shortage of cells at Panasonic added to Tesla’s “production hell” woes just as it began ramping up its big push to make the Model 3. Musk has criticized Panasonic’s pace of battery production as constraining the Model 3 and the Model Y. And Panasonic CEO Kazuhiro Tsuga has predicted that its batteries will “run out” if Tesla continues to expand its business.
Musk’s announcement that Tesla will begin manufacturing its own batteries is aimed at alleviating those bottlenecks. But it wasn’t exactly a state secret. The shift to in-house battery production has been telegraphed by recent acquisitions, leaked photos, patent applications, and research published by Jeff Dahn, one of the pioneering developers of the lithium-ion battery and Tesla’s head of battery research.
But Tesla won’t stop purchasing those batteries anytime soon. In the run-up to Battery Day, Musk tweeted that the company would continue to use batteries supplied by Panasonic, China’s CATL, South Korea’s LG Chem, and others. Not only that, but Tesla would buy more batteries from its suppliers than normal.
This makes sense considering Tesla’s broader ambitions, said Caspar Rawles, an analyst at Benchmark Mineral Intelligence who focuses on the raw materials that go into lithium-ion batteries. “It doesn’t make sense for Tesla to cut these relationships off, it’s future demand will need the capacity — although the company is now at the stage it can tackle vertical integration,” Rawles said.