I never tire of listening to Elon. He is a fountain of insight into the near future. In response to a question about battery density and cost he mentioned a likely 30% increase in volumetric energy in about two years, $100 a kWh at the cell level by the end of the year and perhaps $100 a kWh at the pack level in two years. Regarding charging, he suggested that a ratio of charging:travel times of 1:6 will be the "figure of merit," about double the present. He thinks that current tech can be improved up to 3x. While he was clear that Gen1 cars (like the Model S 2012) could not support the faster standard, he did not exclude any more recent cars and (my interpretation) implied that 2170 packs would support faster charging with SuperCharger v.3, due out towards end of the year. Wow. Even if the rather common Elon time expansion occurs, these are near term, on the horizon improvements.