Electric vehicles have the potential to become the mobile power bank for our homes and offices. But as more scenarios become possible, are two ports better than one?
That seems to be something GM has considered or saved for the future, with a recent patent submit shows a setup that can take full advantage of GM’s dual-layer package used in GMC Hummer EV and coming Chevy Silverado EV and GMC Sierra EV.
The proposed setup is based on a range of controllers and switches, in addition to the built-in ability of the GM pack to act as two different packages in series or in parallel, thus allowing the top and bottom to be temporarily string concatenated. The latter allows for 800 volt charging to take advantage of faster DC 350 kw fast charging hardware.
Ultium EV Platform – GMC Hummer EV
In the GMC Hummer EV, 12 modules are connected in series to form a “pack” or battery layer — which can add more than 100 kwh — while connected in parallel to another nearly identical layer with the same number module.
GM outlines that one charging port can be configured to charge at 800V or 400V, while the other will be connected to another “pack” and only 400V. It is possible to connect them in series while charging both top and bottom packs at the same time using 800V and the first port. Or it could use both ports to charge the upper and lower packages simultaneously at 400V, with the controller capable of selectively connecting them in parallel.
The profile notes that a third configuration could allow the controller to isolate two packs, while in parallel mode, to charge one pack at a time.
Registered GM patent – dual charging port
Furthermore, GM notes that its controller will allow the use of a second CCS charging port to power the accessory at 400V while charging the entire reconfigurable battery system at 800V.
It’s a situation that can be useful if you have equipment that you want to keep running on power from the second port while the truck charges at the first port. Or, perhaps, if you have a smaller EV that you can essentially charge in series to charge, at a lower rate, from that second port.
Separately, GM noted an upgrade to its dual-port setup, with the addition of another switch located adjacent in the circuit with a second charging port that would make both ports 800V compatible.
The company says that its configuration can be extended to other types of motor vehicles, airplanes, ships or rail vehicles.
GM’s proposed layout is similar to that used by the Porsche Taycan and Audi E-Tron GT. In those models, the port on the right is for fast DC charging, while the ports on the sides can be used for AC charging. However, that’s the way to go in those performance EVs; you really can’t use both ports at the same time. An illustration filed with GM’s patent filing shows the proposed ports side-by-side – an arrangement that might make more sense in a fleet’s work or charging bay situation, although individual vans might be better served with gates on either side.
2007 Chevrolet Volt Concept
The patent filing never guarantees that an automaker will actually implement the technology. Sometimes the main motivation is simply strengthening the possibilities for the future.
However, the idea of dual ports is not entirely new to GM. It came up with the idea on its Volt while in concept form, dropping the idea on its way into production. While that might be overkill, it makes a lot more sense for all sorts of different potential power-sharing.
Ford F-150 Lightning has flexible ability to generate loads for backup power source at home or the EV charges through its J1772/Combo port, but it only has one charging port.
GM wireless battery management system for electric vehicle
As for GM, some of the tech it teases as part of its Ultium propulsion kit could play a role in helping players. Its wireless battery management system allows vehicles to easily mix and match modules in different degradation states — even containing different cell types — all in the same package, making it easy to replace just some of those cells . GM has made modules and packages forward-compatible — beyond the present large format lithium-ion pocket cell co-developed with LG — sometime in the middle of the decade or later when lithium metal cells can allow energy densities 600 miles range.