Rivian announced Monday that it will use Samsung SDI battery cells for its R1T electric pickup truck and R1S electric SUV, as well as upcoming commercial vehicles.

Announcement of a battery supplier is a key piece of the information puzzle for the R1T and R1S, which are scheduled to start production this summer. Rivian previously said the R1T would start production at its Normal, Illinois, factory in June, followed by the R1S in August.

Rivian has already discussed a few details of its battery packs, showing some innovative cooling solutions that allow it to pack cells more closely together than Tesla or other EV makers.

This will give the R1T more than 300 miles of range with the 135-kilowatt-hour "Large pack" available at launch. A 180-kwh "Max pack" for the R1T will enable more than 400 miles of range, but won't be available until early 2022. A 105-kwh pack option affording 250 miles of range is also in the works.

Rivian R1T

Rivian R1T

The company claims to have tested the pack in some very extreme environments, and says its battery management system can learn for performance and battery life. That's very important given the designs or the R1T and R1S, which emphasize towing and off-roading.

Rivian appears confident that its battery packs will handle the abuse of owners with active lifestyles. The company revealed last month that it will offer a warranty that beats coverage given on other EVs—out to 175,000 miles.

Samsung SDI is an established battery supplier, providing cells for the BMW i3, among many other vehicles.

Tesla and Samsung were very close to a deal for batteries in 2014, but it reportedly dissolved over issues requiring other components to be bought from Samsung's SDI's sibling divisions.