Tesla and GM are each developing batteries that can last a million miles.

Tesla and GM are each developing batteries that can last a million miles. Neither have yet said exactly when they’ll be ready. GM is “almost kind of there on longer life,” Doug Parks, an executive vice president, said at a May 19 Citigroup Inc. event. The car maker is “experiencing nearly that in some of our products today,” Parks said.

Combustion engine vehicles are currently scrapped in the U.S. after about 200,000 miles, Tesla said in a June 8 report, meaning a longer-life battery pack could dramatically extend a car’s lifespan, particularly useful for taxis or delivery trucks. More important, a million-mile pack could be resold by a consumer to be deployed in a second vehicle, offsetting some of the initial purchase price.

Tesla is planning to provide further details on its battery innovations in the coming weeks at what it’s billing as a “battery day” investor seminar. It had tentatively been scheduled for April but was delayed on account of Covid-19 travel concerns and restrictions.

One critical update investors are expecting: the average cost of batteries used in Tesla’s various models. The carmaker’s numbers typically set the standard for others to catch up to, and the car battery still accounts for about 30% of the total cost of an electric vehicle. Better technology and rapid growth in manufacturing capacity has already sent the price of lithium-ion batteries tumbling, down from more than $1,000 a kilowatt hour to an average of $156/kWh at the end of 2019, according to BNEF.

An industry average battery price of $100/kWh, should be achieved in 2024, BNEF analyst James Frith said at a seminar in May, leading to price parity between electric cars and combustion engine vehicles. Additional savings through 2030 will lower costs further, though they’ll prove harder to achieve and will depend on additional advancements and new technology, according to Frith.

Every battery has three key components: two electrodes, cathode and anode, with an electrolyte—usually a liquid—to allow the battery to charge and discharge.

A key, pending breakthrough will be the addition of silicon into battery anodes in place of graphite. California’s Sila Nanotechnology Inc., which counts Daimler AG among its investors, says the silicon will help make a single charge last at least 20% longer.

The technology is being applied to consumer devices that are due to hit the market next year, said Sila CEO Gene Berdichevsky. There’s also potential for the technology to make its way into some supercars or luxury vehicles as early as 2023—and mainstream vehicles after that, Berdichevsky said. “There's now more engineering resources at the battery makers that we work with,'' he said. “There's more capacity on the production line to try new things."

A more significant advance could be achieved before the end of the decade via the commercialization of solid-state lithium-ion batteries for regular cars. Such a development would enable smaller battery packs, reducing safety risks and dramatically improving energy density, allowing cars to travel much further on a single charge.