The EV battery makers were probably not too happy to see what Tesla is going to do.

After yesterday's Tesla Battery Day, third-party lithium-ion battery manufacturer might be quite surprised and uncertain about the future.

Tesla clearly continues on its path of vertical integration, hinting at significant improvements on the technological level and advancing also on the in-house battery production front.

The pilot plant for 4680 cells is expected to reach a production output of 10 GWh annually at some point in 2021, which alone is a huge level. The target of 100 GWh in 2022 is also very ambitious.

Tesla's Elon Musk said that the automaker will continue to purchase cells from existing (and maybe new) suppliers, because it will not be able to produce enough of its own batteries anyway, but still the share price of the biggest EV battery manufacturers declined.

According to Automotive News, LG Chem went down by 5.5%, CATL by 4.7%, while Panasonic by 4.3%.

2020 Tesla Shareholder Meeting and Battery Day
2020 Tesla Shareholders Meeting and Battery Day

Investors are clearly aware that Tesla is pushing hard to reduce costs and increase energy density. It's a challenging race, which requires tons of R&D investments to keep up with the leaders.

Will the ordinary battery makers from electronics and chemical industries be able to offer a competitive solution for a company like Tesla, which has an advantage of vertical integration? They would have to closely partner with other carmakers to jointly develop battery systems deeply integrated with the vehicles.