Automotive supplier ZF recently unveiled a Porsche Taycan prototype with a number of new components that the company claims can boost cold-weather range by up to a third.
The key to this is what ZF calls a central thermal management system that handles temperature control for both the powertrain and cabin. This is based around a central refrigerant circuit that uses propane inside. It uses half the amount of refrigerant of conventional designs, but still increases cooling capacity by a factor of two, ZF claims. The sealed circuit is maintenance-free.
ZF EVSys800 drive unit
If needed, the central circuit can connect with two separately-controllable water cooling circuits. One serves the electric motor, the other serves power and charging electronics. An 800-volt heat pump is also included to help regulate cabin temperature.
The concept vehicle also has a new drive unit that reworks Porsche’s 2-speed gearbox. It features a coaxial design that uses two planetary gearsets to transfer power from the motor to the wheels in place of conventional input and output shafts. This reduces the weight and size of the gearbox, without compromising efficiency or refinement, ZF claims, adding that the motor is more compact as well.
ZF coaxial reduction gear for EV drive units
The supplier appears to be directly answering some of the concerns of Porsche, which this past year told Green Car Reports that it underestimated the importance of efficiency when the Taycan was first released. In the meantime, Porsche has introduced a number of changes that help boost efficiency and range—including revised motor behavior.
In general, cold-weather EV range varies widely by model, a 2022 report from battery analysis firm Recurrent found. The same company in a separate report found that, for most EV drivers, this just means more time spent charging.
