The Porsche Taycan, when it arrives toward the end of 2019, will likely have the quickest, highest-power DC fast charging of any production vehicle.
But Porsche apparently is already setting its sights higher. Yesterday, as part of a research consortium that includes BMW, it presented a prototype for using CCS-standard charging hardware at up to 450 kw at 800 volts, which can also operate at 400 volts for cars that don't have 800-volt systems. Porsche says that the new hardware promises charging rates three to nine times faster than what’s currently available.
Although charging-station operators would have to make big plans for siting such stations, the hardware doesn’t need to make as much of a leap. Most makers of fast-charging hardware have already targeted charging up to 460 kw, or as high as 500 kw, depending on the maker, at a maximum of 920 to 1,000 volts. The system uses the liquid-cooled cables intended for 150 kw and beyond, and the same connector used by other CCS hardware.
FastCharge 450-kilowatt charging station prototype
In the research prototype, a Cayenne SUV, Porsche points to the “innovative cooling system” that provides “even, gentle temperature control in the battery cells” as one of the keys to the vehicle’s high charging capacity. It does not clarify whether it’s the same system as what’s to be used in the Taycan (and subsequent Audi e-tron GT).
The vehicle, with a 90-kwh battery pack, was put to the test at over 400 kw, which Porsche says allowed it to regain the first 62 miles of range in less than three minutes. Given that one piece of information, and the way that higher-power DC charging often works with current cell technology, it’s likely that the system tapers its power down significantly after that.
A BMW i3 prototype with a 57-kwh battery pack, however, did charge with the system from 10 percent up to 80 percent state of charge—about 165 miles of added range, based on EPA ratings, in just 15 minutes.
The prototype is on a real stretch of German autobahn, and the project is funded by the German government, as part of an $8.9 million Fast Charge research project that started in July 2016. The related consortium includes the BMW Group, Allego, Phoenix Contact, and Siemens, as well as Porsche.