3 ms·

Tesla, who presumably know a fair bit about this, say that battery energy density has been improving at a rate of 7-8% a year. http://www.eetimes.com/electroni

• SeanLuke 14y ago
  That would imply a doubling every nine to ten years. A link from an earlier comment... http://www.akbars.net/images/battery%20energy%20density.png http://www.akbars.net/images/battery%20energy%20density.png ... would imply that this is overoptimistic by at least 2x.