I’ve said it before and I’ll say it again: EV charging infrastructure in this country isn’t where it needs to be. But it is getting better.
A recent video from our friends at the Out of Spec YouTube channel highlights an unexpected solution for filling in some of those charging gaps. Mobile DC fast chargers are here, folks. And they can come in handy if you, like these content creators, just bought your own EV test track and make it a habit to drive electric cars until they conk out.
In a video out this week, Out of Spec’s Kyle Conner takes viewers along as he fast charges his mobile fast charger for the first time. It’s a fascinating look at a very specific type of charging solution that you don’t see every day. Here’s how it works.
This Charge Rigs Flexx, loaned to Out of Spec by the company, consists of a large boxy enclosure with batteries and a DC fast charger. So it’s basically like the battery bank you use for your phone or camp site, but with a whole lot more storage capacity and much more power for both charging and discharging.
The company sells a few models, but this one houses 120 kilowatt-hours worth of batteries and can both charge and discharge at 120 kilowatts. The batteries are lithium-iron-phosphate (LFP) cells. And the battery capacity is enough to fully charge one EV with a fairly large battery—or do several top-ups. It’s mounted to a custom trailer.
The Charge Rigs Flexx can be both DC and AC charged—in other words, it accepts both a fast and a slow charge—and Kyle takes it to an EVgo fast-charging station in the video.
The process ends up being a bit more involved than charging a car, with some switches that need to be flipped behind a locked panel. And Kyle noticed one bug: The charger shows a 99% state of charge for a long while even as the batteries are still filling up.
But by the end of the session, the EVgo charger dispensed 120 kilowatts of juice and topped the Flexx up to a full charge. The charging power output stays pretty consistent throughout the session at 110-120 kW, which is one of the benefits of LFP batteries. Afterward, Kyle calls it a “successful” first charge.
Who Are Portable Fast Chargers For?
So, this is an interesting product. But who are mobile DC chargers for? (Apart from YouTubers specializing in races and range tests.)
Charge Rigs says it’s for businesses that need to charge vehicles quickly without relying on permanent infrastructure, like “fleet operations, construction sites, emergency response, [and] event venues.” Makes sense, especially if you can slow-charge the batteries overnight off of a cheaper plug.
We’ve also seen Tesla deploy it’s own version of this system to alleviate crowding at Supercharger stations during busy holiday travel weekends. Around Christmas, it brought flatbeds fitted with battery-powered Superchargers to several charging stations around the country.
And Charge Rigs isn’t the only game in town here. SparkCharge, a competitor, offers a bunch of different off-grid charging solutions too. That includes trailer-mounted systems and smaller ones that can be wheeled around by an individual. Roadside assistance companies like AAA partner with SparkCharge to help stranded EV drivers get moving again.
If you want to learn more about mobile chargers and the Charge Rigs unit in particular, check out another recent Out of Spec video, in which they take delivery of the Flexx.
These things aren’t going to solve all of America’s charging woes, but they’re definitely an interesting solution for specific use cases.
Contact the author: Tim.Levin@InsideEVs.com
