CEO Elon Musk outlined Tesla's plans to cut electric vehicle battery design and manufacturing costs so radically that a $25,000 car that drives itself will be possible, but the automaker's shares slipped as Musk forecast the change could take three years.
Musk acknowledged that Tesla does not have its ambitious new vehicle and battery designs and manufacturing processes fully complete. The company has frequently missed production targets.
"Nothing Musk discussed about batteries is a done deal," said Roth Capital Partners analyst Craig Irwin. "There was nothing tangible."
Investors had expected two significant announcements at Musk's oft-touted Battery Day on Tuesday: The development of a "million mile" battery good for 10 years or more, and a specific cost reduction target -- expressed in dollars per kilowatt-hour -- that would finally drop the price of an electric vehicle below that of a gasoline car.
Musk offered neither. Instead, he promised over the next several years to slash battery costs in half with new technology and processes and deliver an "affordable" electric car.
"In three years . . . we can do a $25,000 car that will be basically on par (with), maybe slightly better than, a comparable gasoline car," Musk said.
Tesla's market cap dropped $20 billion in just two hours after trading closed Tuesday, as Musk and other Tesla executives presented their new battery and manufacturing strategies. Shares closed down 5.6 percent and dropped another 6.9 percent in after-hours trading.
Musk described a new generation of EV batteries that will be more powerful, longer lasting and half as expensive than the company's current cells.
Tesla's new larger cylindrical cells will provide five times more energy, six times more power and 16 percent greater driving range, Musk said, adding that full production is about three years away.
"We do not have an affordable car. That's something we will have in the future. But we've got to get the cost of batteries down," Musk said.
Tesla expects to eventually be able to build as many as 20 million electric vehicles a year. This year, the entire auto industry expects to deliver 80 million cars globally.
To help reduce costs, Musk said Tesla planned to recycle battery cells at its Nevada "gigafactory," while reducing cobalt -- one of the most expensive battery materials -- to virtually zero. It also plans to manufacture its own battery cells at several highly automated factories around the world.
Tesla will produce the new battery cells initially on a new assembly line near its assembly plant in Fremont, California, with planned output reaching 10 gigawatt hours a year by the end of 2021. Tesla and partner Panasonic now have production capacity of around 35 gigawatt hours at the Nevada battery "gigafactory."
Tesla aims to rapidly ramp up battery production over the next years, to 3 terawatt hours a year, or 3,000 gigawatt-hours -- roughly 85 times greater than the capacity of the Nevada plant.
The automaker plans to produce the new cells via a highly automated, continuous-motion assembly process, according to Drew Baglino, Tesla senior vice president of powertrain and energy engineering.
At the opening of the event, which drew over 270,000 online viewers, Musk walked on stage in a black t-shirt and jeans as about 240 shareholders -- each sitting in a Tesla Model 3 in the company parking lot -- honked their car horns in approval.
Ahead of the event Musk tweeted late Monday that the battery improvements to be unveiled would not reach "serious high-volume production" until 2022.
While average electric vehicle prices have decreased in recent years thanks to changes in battery composition, they are still more expensive than conventional cars, with the battery estimated to make up a quarter to a third of an electric vehicle's cost.
Some researchers estimate that price parity, or the point at which electric vehicles are equal in value to internal combustion cars, is reached when battery packs cost $100 per kilowatt hour.
Tesla's battery packs cost $156 per kilowatt hour in 2019, according to electric vehicle consulting firm Cairn Energy Research Advisors, which would put the cost of a 90-kilowatt-hour pack at around $14,000.
Tesla currently produces batteries in partnership with Japan's Panasonic at its $5 billion Nevada factory, while South Korea's LG Chem and China's CATL supply cells to its Shanghai factory.
Tesla is also building its own cell manufacturing facility at its new factory in Germany and is setting up a battery research and manufacturing facility at its largest vehicle factory in Fremont.
Musk in July also said Tesla was open to license and supply powertrains and batteries to other automakers.
Tesla on Tuesday also introduced a new Model S Plaid, a 520-mile (851-km) range sedan that can reach top speeds of up to 200 mph (322 kph), with deliveries starting in 2021. The Plaid was listed on Tesla’s website on Tuesday at a price of nearly $140,000.