Key to successful e-mobility:

the e-compressor from MAHLE

E-mobility left the starting blocks a long time ago. To help it keep gaining momentum and become a mainstream solution, MAHLE has now added an e-compressor to its portfolio. This is part of the company’s development into an overall systems provider of air conditioning for electric vehicles. Find out here what the fuss about this crucial component is all about, where the e-compressor was developed, and who was involved.

Without a battery, nothing works at all

The battery is definitely one of the most important components in an electric vehicle—in terms of cost as well as performance. Its significance is comparable to the internal combustion engine—and it needs to be looked after just as carefully. Maintaining the right temperature is crucial: for the battery’s service life and charging speed as well as the cruising range of the vehicle. Getting the battery temperature right is advantageous in a number of ways.
The electric compressor from MAHLE is therefore a key component in an electric vehicle’s refrigerant circuit. It ensures the interior is neither too hot nor too cold, and controls the battery temperature—and when it works optimally, so does e-mobility.

“We once revolutionized mobility with the aluminum piston. The e-compressor has the same potential. We want to shape and develop this change too.”
Dr. Armin Frommer, Head of Product Development E-Compressors

Full-charge competence

The electric compressor is made up of many precisely coordinated components. John O’Brien, systems engineer, explains: “The e-compressor is crucial for a comfortable interior and battery cooling—during both operation and charging.” His team partner Jonathan Hammond adds: “The cooling performance provided by the e-compressor is vital when it comes to increasing charging capacity.” Good charging capacity is necessary in order to make e-mobility just as much a part of everyday life as combustion technology is today.

A cross-border development

As exciting as the young field of e-mobility is, it also represents a major challenge. Not just for MAHLE or its customers, but for the whole world. Developing the right solutions requires close cooperation between various competences in interdisciplinary teams and the courage to be pioneers. This applies particularly to the e-compressor developed by MAHLE in the USA, which comprises a number of components made by MAHLE in various countries. For example, MAHLE Electric Drives in Slovenia supplies the electric motor—the “heart”—with which the e-compressor can drive itself and hence be independent of the combustion engine. In contrast, MAHLE Electronics in Spain provides the “brain” of the e-compressor: the power electronics. The production of the e-compressor itself commenced this year at MAHLE Compressors in Hungary.

“Electronics is the new power of mobility. With it, we have created the most powerful e-compressor on the market.”
Jose Antonio Castillo, Head of Development HV Electronics at MAHLE Electronics, Valencia/Spain

Operation of the e-compressor

1) Compressor: the e-compressor compresses gaseous refrigerant to high pressure and high temperature. The hot gas is then pumped to the condenser.
2) Condenser: in the condenser, the gaseous refrigerant is cooled and liquefied by the ambient air.
3) Expansion valve: the liquid refrigerant passes through an expansion valve where its pressure and temperature are reduced.
4) The largely liquid refrigerant flows through both the evaporator and chiller, where the evaporation process takes place.
4 a) Evaporator: heat is removed from the air passing through the evaporator and into the cabin, which is cooled.
4 b) Chiller: the refrigerant circuit and battery cooling circuit are connected via the chiller. This enables the transfer of heat from the battery coolant circuit to the refrigerant circuit.
5) The vaporized refrigerant returns to the e-compressor, and the cycle begins again.

*Simplified representation of the refrigerant circuit without heat pump function

The air conditioning compressor produces cool air from heat energy. It’s based on the principle of an air conditioning circuit in which every single component counts.

Design of the e-compressor

6) Refrigerant inlet
7) Inverter (power electronics)
8) Refrigerant outlet
9) Electric motor
10) Scroll compression mechanism

You can discover more about how an air conditioning compressor works in these two articles:

>> Become an air conditioning expert with MAHLE

>> Climate control: everything workshop professionals need to know


We regularly provide technical tips relating to the powertrain, thermal management, and mechatronics in automobiles.


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