I believe Rivian has not officially announced who will be their battery supplier but there are plenty of articles on the internet deducing it will be (already is?) LG Chem. If that pans out to be true, I wonder what measures Rivian is taking, if any, to ensure their production schedule will not be affected by a battery shortage as is what is currently happening to Audi and delaying their production of the new e-Tron EV SUV. Source: Teslarati - "Audi e-tron customers face more delivery delays, fines for canceled orders: report" Excerpt: "Audi’s delays with the rollout of the e-tron come amidst reports that the German automaker is running into issues with the supply of the SUV’s batteries, which are sourced from LG Chem, the same company that provides cells for other EVs like the Porsche Taycan and the Jaguar I-PACE." Even with RIvian's earliest production over a year away, there will be even more EVs entering the market between now and late 2020 adding to the demand for batteries.