Tesla refers to the Roadster's battery pack as the Energy Storage System or ESS. The ESS contains 6,831 lithium ion cells arranged into 11 "sheets" connected in series; each sheet contains 9 "bricks" connected in series; each "brick" contains 69 cells connected in parallel (11S 9S 69P). The cells are of the 18650 form factor commonly found in laptop batteries. Sources disagree on the exact type of Li-Ion cells—GreenCar says lithium cobalt oxide (LiCo), while researchers at DTU/INESC Porto state lithium manganese oxide (LMO). LiCo has higher reaction energy during thermal runaway than LMO. English translation
