In context: Tesla set the stage for this milestone back in 2019 when it pulled the trigger on a major battery tech acquisition. The EV maker scooped up Maxwell Technologies and its promising "dry electrode" coating process, originally developed for supercapacitors. At the time, Tesla was still relying on partnerships with suppliers like Panasonic for cell production. But the Maxwell deal signaled Elon Musk's ambitions to bring that technology fully in-house.

Tesla has rolled out its first Cybertruck equipped with dry battery electrode cells. The matte black electric pickup was unveiled this month, marking a major milestone for the company's in-house battery technology.

The unveiling was shared by Tesla engineer Cole Otto on LinkedIn, who announced the company had kicked off vehicle testing with the "groundbreaking in-house dry cathode 4680 cells" in the Cybertruck. Pictures show the 4680 team proudly posing with the matte black prototype EV.

"This is a significant milestone in advancing both technology and cost efficiency," Otto wrote.

If you've been following the Cybertruck saga, you may have already caught a glimpse of this mysterious matte black prototype. Images of it circulated last month after being spotted during a flyover of Tesla's Giga Texas factory by Joe Tegtmeyer, who's been keeping a close watch on the plant's progress. Bonne Eggleston, senior director of Tesla's 4680 program, confirmed it was indeed the dry electrode Cybertruck.

Dry battery electrodes (DBE) on the Cybertruck are a big deal. They were hyped as a key part of Tesla's plan to slash battery costs by 50% when first announced at the company's Battery Day event back in 2020. By skipping the expensive furnace "baking" process, the dry coating method uses far less energy and factory space.

Scaling up that dry battery tech from Maxwell proved incredibly difficult though. Tesla ended up initially making 4680 cells without the dry electrode process, missing out on a lot of the projected cost savings as a result.

The first generation 4680s made some advances by using a larger cell format with less packaging and assembly. But they suffered from lower energy density and slower charging, leading Tesla to revert to suppliers like Panasonic and LG for a while.

The Cybertruck is now slated to use Tesla's second-generation "Cybercell" 4680 batteries. And if this dry electrode prototype is any indication, the company has finally cracked the code on scaling up that cheaper dry coating method.

Scaling up the dry coating method could slash Tesla's battery costs, which could impact vehicle pricing, should the company decide to pass on any savings to consumers. But the road has been rocky, with suppliers like Panasonic and LG reportedly undercutting Tesla's 4680 costs amid scaling challenges. Musk reportedly set a year-end deadline to cut costs before potentially scrapping the 4680 project altogether.

However, with the dry electrode Cybertruck now seemingly road-ready, it looks like Tesla may have turned a crucial corner just in time.