Thursday, November 9, 2017

Extreme fast chargers for electric vehicles – New report on how to get there

Following on the heels of the Department of Energy report on how to implement a network of Fast Chargers for electric vehicles in this country (see my posting here), the agency has published a new study detailing the research and development needed to get to the next generation of chargers: Extreme Fast Chargers (Enabling Fast Charging: A Technology Gap Assessment, available here).
The authors define Extreme Fast Charging as technology that would charge an EV in less than 10 minutes with enough “juice” to go 200 miles.  This rate of charging (roughly 20 miles of range for every minute of charging) is far better than the current best technology (Tesla Superchargers can give you up to 5.6 miles per minute).  At this rate, long-distance EV travel would no longer impose a time penalty, compared to internal combustion vehicles.  And we Americans do obsess about our time!
As you might expect, there are lots of engineering problems involved in designing and deploying an Extreme Fast Charging system.  The report lays out all the problems in detail (be prepared to go deep into the scratchy weeds) with a focus on batteries, vehicles, and infrastructure. 
With regard to infrastructure – my usual space – the report says that “there is a distinct need to understand how fast charging up to 400 kW will impact the electrical grid, the design of EVSE [chargers], impacts brought by demand charges, and XFC-related infrastructure costs.”  In other words, plenty of R&D work to be done.
Is it worth it?  The authors note that the deployment of DC Fast Chargers (no one has convincingly explained to me why we can’t call these Level 3 chargers) has already had effects on EV travel: “With the emergence of DCFC (up to 50-kW) capability for Nissan Leafs, it has been observed that longer range trips using BEVs have occurred in the northwestern portion of the United States. The ability to use DCFC for longer trips, combined with automotive manufacturers producing a greater number of BEVs with range above 100 miles, closes the ‘range anxiety’ gap that exists between ICEVs and BEVs.”

Lots of room for TRB papers!

No comments:

Post a Comment