Modern electric vehicles present complex challenges for efficient thermal management throughout the year; and because they should place as light a load on the drivetrain battery as possible — particularly in winter — Mahle has developed a compact and economical system based on its ITS (Integrated Thermal System) heat pump, which can increase the winter range of the vehicle by up to 20%.
Due to the lack of steadily available waste heat from the engine, most electric vehicles today rely on direct resistive heating (from electric heaters) to heat the interior of the vehicle and the traction battery in winter.
This extra load on the drivetrain battery in low temperatures can reduce the range of a fully charged electric vehicle by up to half.
In summer as well, the range is shortened by the additional energy required to cool the drivetrain battery and the interior of the vehicle.
The ITS from Mahle (
www.mahle.com) combines various thermal components into one system that functions in several modes.
Central to its architecture is a semi-hermetic refrigerant circuit, comprising a chiller, a coolant-cooled condenser (i-condenser), a thermal expansion valve, and an electric drive compressor.
The i-condenser and the chiller have the same function as the condenser and evaporator in a conventional refrigerant circuit.
In this case, however, instead of exchanging heat with air, the refrigerant exchanges heat with the coolant, thus generating hot and cold coolant flows.
The ITS uses ‘R1234yf’ ASA refrigerant and the conventional vehicle coolant as the medium for heat transport between the cooling circuit and the various heat sources and heat sinks in the vehicle.