E-PAPER-a E-PAPER-b Logo_Geschaeftsbericht_DE Logo_Geschaeftsbericht_EN Logo_MAHLE Menu_close menu PDF-neu PDF Pfeil_links Pfeil_oben Pfeil_rechts plain plus Zitat_Grafik

The best of three worlds

Just as nothing stays the same, mobility is currently in a state of transformation throughout the world. And only one thing is certain: the powertrain of the future will be versatile. Even if trends can be predicted, it remains to be seen which technologies will emerge as leading contenders over the medium and long term. That’s why MAHLE has chosen to feature conventional combustion engines, hybrid drives, and fuel cell drives—all on an equal footing—at this year’s IAA.

Optimized total cost of ownership: fuel savings of 5 percent and extended service intervals to boot

By becoming a highly efficient and clean drive, the combustion engine is securing pole position for itself in the drive mix of the future. As a result of this development, the complete system, comprising the powertrain and its peripherals, is now substantially more complex. To improve efficiency and reduce emissions in this area, it is essential to effectively manage an ever increasing number of interactions and overcome challenges that are often contradictory in nature. Thanks to its comprehensive systems expertise, MAHLE is ideally positioned to deliver solutions aimed at reducing consumption and emissions.

For operators of commercial vehicle fleets, a sober analysis of cost accounting is high on the list of priorities. Rising oil prices have resulted in an increasing awareness of hybrid drives—and with good reason. From an economic perspective, this type of drive is extremely appealing for commercial vehicles because it can be retrofitted as a simple box from MAHLE and provides fuel savings of approximately 5 percent.

Immediate friction reduction in the engine, an optimized thermal cycle, and consistent, on-demand control of the auxiliary components: at the IAA, MAHLE will showcase winning solutions that are sure to wow customers. Longer service intervals and increased load capacity for critical components are also key factors. In short, with an eye on the big picture, MAHLE is systematically reducing the total cost of vehicles over the entire service life.

New generation of thermally insulating piston coatings

A new generation of MAHLE piston coatings is being developed with the goals of increasing efficiency and minimizing emissions. These coatings are intended to guide and reduce the heat entering the pistons. This initially reduces the demand for piston cooling, and the increased exhaust gas temperature allows a higher quantity of energy to be extracted by waste heat recovery (WHR) systems. At the same time, the higher exhaust gas temperature permits faster heating of the exhaust gas aftertreatment system following the cold start. The resulting decrease in NOx emissions makes it easier to comply with current and future legislation.´

MAHLE achieves additional positive effects by optimizing the piston galleries—for instance, the MonoLite® piston with its kidney-shaped cross section. This allows a temperature reduction of up to 20 kelvin without any negative impact on the aging process of the oil used. The combination of reduced oil flow and a small compression height helps to minimize friction and fuel consumption.

eWHR and Mild Hybrid—combined for maximum efficiency

With its e-Waste Heat Recovery (eWHR) system, MAHLE offers a true enabler for economically efficient hybrid technology in long-distance hauling and distribution transport. And it comes packed into the compact MAHLE Boost Box. The eWHR system in a box extracts heat from the exhaust flow. It is then converted into electrical energy that can be used in a 48-volt electrical system to supply electrified auxiliary consumers or be fed directly into the powertrain via an electric motor. Fuel savings of up to 5 percent can thus be achieved. But at MAHLE, we’re always thinking one step ahead.

To reach maximum efficiency, it’s possible to add a Mild Hybrid component to the eWHR system. Using a Mild Hybrid, the electrical energy obtained in the eWHR system can be transferred to the powertrain in the form of mechanical energy and the energy released during braking can be recovered.

Alternative fuels: MAHLE solutions for CNG/LNG engines with HPDI injection

CNG/LNG drives for commercial vehicles offer substantial CO2 savings potential. Even if fossil sources are used, these drives already save up to 15 percent. When using renewable methane gas, it is possible to make the solution completely CO2 neutral. Gasoline engines can be operated at a higher efficiency thanks to the greater knock resistance of CNG/LNG. Existing powertrain concepts can be adapted without major development effort.

The challenges here include the increased exhaust gas temperature under stoichiometric operation. To solve this problem, MAHLE has developed technologies for cooled exhaust gas recirculation, which reduce the combustion temperatures to protect the engine components from damage and prevent knocking.

MAHLE already produces engine components in series for CNG/LNG engines with indirect injection. In the medium term, internal carburetion using HPDI technology will provide a further increase in efficiency. To achieve optimal results in terms of durability and efficiency with this high-pressure, direct-injection approach, MAHLE is currently developing a special series of pistons, making use of existing expertise in the design of complex piston bowls and cooling channel geometries.

Pioneer in hybrid technologies

Particularly in the commercial vehicle sector, new regulations concerning the reduction of CO2 and emissions will be the technological driver in the ongoing development of the powertrain. Even more than in the passenger car segment, the broad spectrum of drive architectures and application areas will produce a rather heterogeneous environment.

Solutions from MAHLE are making cooling architectures for hybrid commercial vehicles more simple, durable, and efficient. Reduced package constraints mean it’s possible to give the front end an aerodynamic design. Lithium-ion batteries in particular must be constantly kept within a well-defined temperature window. MAHLE was a pioneer in this field, with its first refrigerant-based battery cooling systems already in series production in 2009. But cooling and temperature control of drive components aren’t the only crucial factors for hybrid vehicles: interior air conditioning must also be maintained while the combustion engine isn’t running.

With the Visco® hybrid fan drive, MAHLE offers a solution tailored specifically to hybrid drives. The MAHLE technology combines the advantages of the Visco® drive with those of electric actuation, including demand-based fan performance control, increased efficiency, and energy recuperation.

Strong alternative—new opportunities

Throughout the world, the number of vehicles equipped with fuel cell drives is increasing slowly but steadily. This opens up new opportunities for heavy-duty commercial vehicles. Promising avenues in this segment include weight savings and extension of the cruising range in comparison with battery-powered solutions. With our holistic system portfolio for fuel cells, we at MAHLE are your dynamic development partner in air and thermal management as well as in power electronics.

The air management of fuel cells places extremely high demands on the components used. To prevent damage to the cell, harmful gases such as SO2, O3, NOx an NH3 as well as particles need to be separated reliably. MAHLE has developed a highly effective filter medium for this purpose.

Fuel cells are also sensitive to oil admixtures. The electric compressor used to compress the supply air flow must therefore be oil-free. The water balance of a polymer electrolyte fuel cell significantly affects efficiency and service life. Therefore, it’s not sufficient to filter the external air supplied to the fuel cell—its humidity must also be precisely controlled. For this purpose, MAHLE—together with affiliated partners and with funding from the German Federal Ministry of Economics and Technology—develops a flat membrane humidifier which ensures as an integrated solution that the supplied air is humidified reliably.

Deionized coolant is used to cool the fuel cell. As a result, the charge air coolers used must be resistant to ionized water. MAHLE presents a new generation of charge air coolers that meet these requirements thanks to a special soldering process.

The result of this holistic systems approach is the plastic exhaust air pathway optimized by MAHLE for fuel cell vehicles. It offers weight savings of around 70 percent in comparison with steel designs and dramatically reduces audible resonance while retaining as much design freedom as possible.

The use of fuel cells leads to more complex cooling systems and larger radiators. This is due to the need for three separate circuits for the fuel cell stack, for the battery and electronics as well as for the electric motor. These are necessary due to the overall increase in waste heat and the reduced temperature in comparison with the combustion engine. A higher cooling air flow has to be managed in order to compensate for the lower temperature differential between the internal and external temperatures. MAHLE develops series production solutions for the temperature control of batteries, power electronics, and electric motors as a complete system including solutions for monitoring the fuel cell stack.

The MAHLE Fuel Cell Monitor is used to control the fuel cell stack. It enables the constant monitoring of voltage, temperature, and performance of the fuel cell and thus assists in operating commercial vehicles with fuel cell drives with maximum efficiency and reliability.