Tesla Supplier Shows Off More Powerful Battery

Mr. Musk, Tesla’s chief executive, has been touting the 4680 since a battery event he held in September 2020. In July of this year, he said: “From a physics standpoint, this is the best architecture, and from an economic standpoint, it is the lowest-cost way to go.”

During its earnings call in October, Tesla said that it expected vehicles with battery packs composed of 4680 cells to be delivered next year.

Mr. Musk has said putting more energy capacity into each battery cell, along with other improvements, should help EVs boost their power and drive longer on a single charge. A related technology incorporated in the 4680 battery cells allows them to charge faster.

However, Mr. Musk has also said that manufacturing the new battery on a large scale is a challenge Tesla and its partners haven’t fully overcome. “Prototype production is easy, but high-volume production is hard,” he said in July.

The head of Panasonic’s battery unit,

Kazuo Tadanobu,

said his company sees the light at the end of the tunnel and is moving beyond prototypes.

“We’ve got the technology under our belts now, and we’re moving ahead with preparations for commercialization soon,” he said.

Panasonic plans to start test production of the 4680 battery cells in Japan by March 2022, Mr. Tadanobu said. He described the product as tailor-made to Tesla’s requirements and said Panasonic planned to supply it to the U.S. company, but he declined to give details.

Panasonic has supplied batteries for Tesla cars for more than a decade, and the two companies jointly operate what Tesla calls the Gigafactory in Nevada. After years of losses, Panasonic has said the unit that supplies Tesla is now profitable.

Once the exclusive supplier of batteries for Tesla, Panasonic lost that status when Mr. Musk added other suppliers including China’s Contemporary Amperex Technology Co. or CATL.

Mr. Tadanobu said he wasn’t worried about losing business, saying Tesla was ready to buy everything Panasonic could make and then some because of higher demand for EVs.

“Tesla’s expectations for shipments from our North American factory are extremely strong,” he said.

After a recent expansion, Panasonic’s annual North American battery capacity has risen to 38-39 gigawatt hours, up from 35 gigawatt hours in the year ended March 2021, the company said. That would be enough to provide batteries for more than 400,000 Tesla Model S vehicles.

Write to Peter Landers at peter.landers@wsj.com and Yang Jie at jie.yang@wsj.com