5. http://esmuc.info/dispara2/TeslaRoadsterBatterySystem.pdf
“The Tesla Roadster battery pack is comprised of about 6800 of these 18650 cells, and the entire
pack has a mass of about 450kg.” This is a report written, The Tesla Roadster Battery System
Tesla Motors, in August 16, 2006, by Gene Berdichevsky, Kurt Kelty, JB Straubel and Erik Toomre. This is important because it talks about the battery technology used. I will elaborate on this information and the report more so in the paper.

9. http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6V2W-4VYW6FD-3...
“The energy density of batteries is two orders of magnitude below that of liquid fuels. However, this information alone cannot be used to compare batteries to liquid fuels for automobile energy storage media. Because electric motors have a higher energy conversion efficiency and lower mass than combustion engines, they can provide a higher deliverable mechanical energy density than internal combustion for most transportation applications.” Source: Corrigendum to “Batteries: Higher energy density than gasoline?” [Energy policy 37 (2009) 2639–2641] Energy Policy, Volume 37, Issue 9, September 2009, Page 3709. This source points out the efficiency advantages of electric motors versus combustion engines.