A few months back, electric pickup truck startup Rivian Automotive filed a patent application entitled 'Configurable Battery Pack For Fast Charge.' Essentially, its voltage switching mechanism allows 800V charging on a 400V battery pack (or 900V on a 450V, etc). The tech can also handle a battery module fault without disconnecting the load.
If Rivian is able to bring this tech to market, it will speed up the electric vehicle charging process and make EVs less expensive. Rivian doesn't officially talk about patents. We do know its vehicles – the R1T pickup truck and R1S three-row SUV – will have a maximum range of 400 miles using a 180 kWh battery pack. Rivian previously said its vehicles could add about 200 miles in 30 minutes via fast-charging stations at up to 160 kW.
Currently, the Porsche Taycan tops at 270 kW charging. The Tesla Model 3 Long Range is at 250 kW. Rivian is now saying it will top at 300 kW, likely due to the system described in the patent. There's more information in this video from a few months back. Tesla Raj checks out Rivian's vehicles and chats with Rivian's founder, RJ Scaringe.
There's a lot we still don't know here. Until we have more specifics and are aware of taper and mi/kWh (or Wh/mi), we won't really be able to compare it to something like the Tesla Model 3 charging at a V3 Supercharger. Efficiency is a critical factor as well. At this point, there aren't future plans to exceed 350 kW fast-charging infrastructure anyhow, but it's still interesting to dive into this information.
*Hat tip to Gary Exner for discovering and dissecting these details.