“It’s not going to happen in a year from now. It’s going to be hard. But I think we can get down to five to 10 minutes,” Straubel said in an interview with MIT Technology Review. He noted that the current superchargers, which deliver 120 kilowatts of electricity, “seemed pretty crazy even 10 years ago.” Conventional public charging stations deliver well under 10 kilowatts.
Straubel says Tesla has been able to rapidly improve charging because it designs and builds all of the key components itself, including the chargers, the electronics for monitoring the battery pack, and a cooling system for the battery. They’re all optimized to work together in a way that’s not easy for systems built to accommodate many different models of electric vehicles...
Achieving five-minute charges will require not only further improving the charging system, but also improving the interface with the electrical grid. As it is, only some places on the grid can handle 120-kilowatt charging. Drawing large amounts of power from the grid also incurs demand charges from the utility, increasing the cost of the system.
Storing solar power in batteries in the charging station could also be helpful to operators of the power grid (see “Wind Turbines, Battery Included, Can Keep Power Supplies Stable”). They could provide utilities a way to moderate fluctuations on the grid, something that’s becoming more important as more intermittent sources of power, such as solar and wind, are added. Tesla plans to test such a system soon in California. It could charge utilities for this service, which, Straubel says, could help offset the cost of the stations.