Elon Musk ended Tesla’s big battery event Tuesday evening, with some big promises about the pricing Tesla’s future cars and the announcement of a new ultra-fast version of today’s Model S.

After reviewing improvements in Tesla’s own battery designs and battery manufacturing capabilities, improvements that could result in huge reductions in battery costs, Musk promised a $25,000 Tesla electric car that would be available in about three years.

That would be much cheaper than any car Tesla has made so far. Musk has a history of sometimes under-delivering on promises, or even not delivering at all. Years ago, Tesla promised a $35,000 electric car, the Tesla Model 3, but even then the Model 3 was only available at that price for a short time.

Musk also promised that the $25,000 car would be capable of driving fully autonomously, a difficult feat because the sensors and other equipment needed for even partly autonomous driving are expensive.

Musk tries to downplay expectations for Tesla’s ‘Battery Day’

Musk also announced that Tesla is taking orders now for the new three-motor Tesla Model S with “Plaid Mode,” a version capable of producing 1,100 horsepower. This car will be able to go from zero to 60 miles an hour in under two seconds and run a a quarter-mile drag strip in under nine seconds. Costing about $140,000, the Model S Plaid will have a top speed of 200 miles an hour and will be able to go 520 miles on a full charge, according to Tesla.

By comparison, the Dodge Challenger SRT Demon, a specialized drag strip car, was capable of going from zero to 60 in 2.3 seconds and running a quarter-mile in 9.65 seconds, according to Fiat Chrysler Automobiles. Customers can order the Model S Plaid now, Musk said, and the first ones will be delivered by the end of next year.

The name “Plaid Mode,” like that of the the slightly slower “Ludicrous Mode” available in today’s Model S, is taken from the movie Spaceballs, a 1987 parody of Star Wars directed by Mel Brooks. In Star Wars, when spaceships entered “hyperspace” and were traveling faster than the speed of light, the movie screen filled with streaks of smeared starlight. In Spaceballs, a spaceship could go so fast that the streaks of lights became plaid.

During the lengthy presentation, Musk and Andrew Baglino, Tesla’s head of powertrain development, detailed improvements the company has made in its battery design and battery manufacturing capabilities. These improvements could lead to massive reductions in battery costs per kilowatt hour, a measure of a battery’s power-holding capabilities, they said.

Musk also outlined a new engineering structure for future Tesla cars in which the front and rear framework of the car would each be made of a single cast piece of aluminum alloy. These would be joined to the battery pack which would, itself, actually form a major part of the car’s structure.