With the GenH2 Truck, Daimler Trucks is demonstrating for the first time which specific technologies the manufacturer is driving forward at full speed so that heavy-duty fuel-cell trucks can perform flexible and demanding long-distance haul operations with ranges of up to 1,000 kilometers and more on a single tank of hydrogen.
Martin Daum, Chairman of the Board of Management of Daimler Truck AG and Member of the Board of Management of Daimler AG, and Andreas Scheuer, Federal Minister of Transport and Digital Infrastructure, in front of the Mercedes-Benz GenH2 Truck.
Daimler Trucks plans to begin customer trials of the GenH2 Truck in 2023; series production is to start in the second half of the decade. Due to the use of liquid instead of gaseous hydrogen with its higher energy density, the vehicle’s performance is planned to equal that of a comparable conventional diesel truck.
Daimler Trucks also presented for the first time a preview of a purely battery-powered long-haul truck, the Mercedes-Benz eActros LongHaul, which is designed to cover regular journeys on routes that can be planned in an energy-efficient manner. Daimler Trucks plans to have the eActros LongHaul ready for series production in 2024. Its range on one battery charge will be approximately 500 kilometers.
Additionally, with the Mercedes-Benz eActros for distribution transport, which was already presented in 2018 and has been tested intensively since then by customers in everyday transport operations, Daimler Trucks will start series production of a purely battery-powered heavy-duty truck next year. The range of the series-produced eActros on one battery charge will significantly exceed that of the prototype’s approximately 200 kilometers.
Daimler Trucks is pursuing similar vehicle schedules for the North American and Japanese markets as it is for Europe. By the year 2022, Daimler Trucks’ portfolio in its main sales regions—Europe, the US and Japan—is to include series-produced vehicles with battery-electric drive. The company also has the ambition to offer only new vehicles that are CO2-neutral in driving operation (“from tank to wheel”) in Europe, North America and Japan by 2039.
ePowertrain. As a new worldwide modular platform architecture, the ePowertrain will be the technological basis of all medium- and heavy-duty CO2-neutral, all-electric series-produced trucks from Daimler Trucks whether powered purely by batteries or by hydrogen-based fuel cells. It will feature high levels of performance, efficiency and durability. With the ePowertrain, Daimler Trucks plans to achieve synergies and economies of scale for all relevant vehicles and markets.
The technological heart of the ePowertrain is, as a first step, the integrated electric drive, the eDrive. This is used in the form of an e-carrier concept, i.e., an e-axle with one or two integrated e-motors including transmission. The eDrive is an in-house development by Daimler experts and offers numerous advantages over concepts with one central motor. For example, the more compact design allows a larger space to install a larger battery with a higher capacity, which has a positive effect on range.
The high battery capacity also ensures high power transmission to the e-axle, thus allowing continuous power delivery. The recuperation potential also increases due to the combination of a large battery with very powerful e-motors.
The eDrive is to be applied in various vehicles at Daimler Trucks in the medium- and heavy-duty segment worldwide—whether with purely battery-electric or hydrogen-based fuel-cell drive. The eDrive is designed as a drive family consisting of different variants, the first of which will have its premiere in the series-produced version of the Mercedes-Benz eActros. Within a modular system, the eDrive can be tailored to suit the market, segment and vehicle type.
The global concept of the modular ePowertrain thus creates synergies with regard to technology developments for different markets and segments, as well as economies of scale through larger numbers of uniform components. This in turn results in competitive costs that can be passed on to customers. In addition, a high proportion of components taken over from conventional powertrains is planned to contribute to competitive development and production costs.
We are consistently pursuing our vision of CO2-neutral transport with a focus on the genuinely locally CO2-neutral technologies battery power and hydrogen-based fuel cells, which have the potential to succeed in the market in the long term. This combination enables us to offer our customers the best vehicle options, depending on the application. Battery power will be rather used for lower cargo weights and for shorter distances. Fuel-cell power will tend to be the preferred option for heavier loads and longer distances.
Our customers make rational purchasing decisions and are unwilling to compromise on their trucks’ suitability for everyday use, tonnage and range. With our alternative drive concepts from Mercedes-Benz – the GenH2 Truck, the eActros LongHaul and the eActros – and our electric trucks of the Freightliner and FUSO brands, we have a clear focus on customer requirements and are creating genuine locally CO2-neutral alternatives for them. We have now set out the key technological specifications of our electric trucks so that the requirements are known to everyone involved at an early stage. It is now up to policymakers, other players and society as a whole to provide the right framework conditions. To make CO2-neutral all-electric vehicles competitive, regulatory and government action is needed, including the necessary infrastructure for charging with green electricity and for the production, storage and transport of green liquid hydrogen.
—Martin Daum, Chairman of the Board of Management of Daimler Truck AG and Member of the Board of Management of Daimler AG
The GenH2 Truck is based on the capabilities of the conventional Mercedes-Benz Actros long-haul truck with regard to tractive power, range, and performance. For example, the series-production version of the GenH2 Truck is to have a gross vehicle weight of 40 tons and a payload of 25 tons. Two special liquid-hydrogen tanks and a particularly powerful fuel-cell system will make this high payload and long range possible, and therefore form the core of the GenH2 Truck concept.
Fuel cell systems. Daimler experts can draw on existing expertise for the development of liquid-hydrogen tanks, and they are also cooperating closely with a partner. With regard to fuel cells, the manufacturer benefits from its experts’ decades of experience, in terms of technology as well as production methods and processes. This represents an enormous advantage.
In April this year, Daimler Truck AG concluded a preliminary, non-binding agreement with the Volvo Group to establish a new joint venture for the development to series maturity, production and commercialization of fuel-cell systems for use in heavy-duty commercial vehicles and other applications.
Joining forces will decrease development costs for both companies and accelerate the market introduction of fuel cell systems. The joint venture is to benefit from the expertise of Daimler Truck AG and the Volvo Group. To facilitate the joint venture with the Volvo Group, Daimler Truck AG has brought together all Group-wide fuel-cell activities in the newly founded subsidiary Daimler Truck Fuel Cell GmbH & Co. KG.
Liquid hydrogen. Daimler Trucks prefers to use liquid hydrogen (LH2), because in this state, the energy carrier has a far higher energy density in relation to volume than gaseous hydrogen. As a result, the tanks of a fuel-cell truck using liquid hydrogen are much smaller and, due to the lower pressure, significantly lighter. This gives the trucks a larger cargo space and higher payload weight. At the same time, more hydrogen can be carried, which significantly increases the trucks’ range. This makes the series GenH2 Truck, like conventional diesel trucks, suitable for multi-day, difficult to plan long-haul transport and where the daily energy throughput is high.
Daimler Trucks is currently pressing ahead with the development of the necessary tank-system technologies to make liquid hydrogen usable also in mobile applications as an energy source for series-produced fuel-cell trucks. The storage of cryogenic liquid hydrogen at -253 ˚C is already common practice in stationary applications, for example in industry or at hydrogen filling stations. This also applies to the transport of liquid hydrogen as cargo.
Interaction between battery and fuel-cell systems. The two stainless-steel liquid-hydrogen tanks intended for the series version of the GenH2 Truck will have a particularly high storage capacity of 80 kilograms (40 kg each) for covering long distances. The stainless-steel tank system consists of two tubes, one within the other, that are connected to each other and vacuum-insulated.
In the series version of the GenH2 Truck, the fuel-cell system is to supply 2 x 150 kW and the battery is to provide an additional 400 kW temporarily. At 70 kWh, the storage capacity of the battery is relatively low, as it is not intended to meet energy needs, but mainly to be switched on to provide situational power support for the fuel cell, for example during peak loads while accelerating or while driving uphill fully loaded.
At the same time, the relatively light battery allows a higher payload. It is to be recharged in series-production vehicles with braking energy and excess fuel-cell energy. A core element of the sophisticated operating strategy of the fuel-cell and battery system is a cooling and heating system that keeps all components at the ideal operating temperature, thus ensuring maximum durability. In a pre-series version, the two electric motors are designed for a total of 2 x 230 kW continuous power and 2 x 330 kW maximum power. Torque is 2 x 1577 N·m and 2 x 2071 N·m respectively.
Mercedes-Benz eActros LongHaul offers advantages depending on use case. The Mercedes-Benz eActros LongHaul battery-powered long-haul truck will be in the same vehicle class as the GenH2 truck. Its features will be largely identical to those of the series-produced GenH2 Truck or a conventional diesel truck. The comparatively short range of the eActros LongHaul on one battery charge is offset by its high energy efficiency, as battery electric drive has the highest efficiency among alternative drive systems. This offers transport companies significant advantages in the application scenarios envisaged for the eActros LongHaul due to its low energy costs.
Many of the long-haul applications in the practical operations of transport companies do not require a range greater than the approximately 500 kilometers that the eActros LongHaul will be able to cover on one charge. In addition, legal requirements regarding truck drivers’ driving times limit the need for longer ranges, depending on the case. In the EU, for example, truck drivers have to take a break of at least 45 minutes at the latest after 4.5 hours of driving.
During this time, thanks to the latest charging technology, the battery can be charged with a large proportion of the energy needed for the ongoing journey. The eActros LongHaul will therefore be the right choice for transport companies for regular use on routes that can be planned and with the appropriate distances and charging possibilities.
Importance of depot charging. With its market launch in the middle of the decade, the eActros LongHaul will be available some time before the GenH2 Truck. The required infrastructure can also be set up sooner—and at comparatively low cost—by the transport companies themselves for charging at their depots. This depot charging is the most important step for the use of the eActros LongHaul, and means that the first areas of application can already be covered.
Another key component is opportunity charging for range extension, for example, while unloading or loading when the electric truck is anyway stationary. In the future, public charging at publicly accessible stations along main transport routes will also become increasingly important—a nationwide charging infrastructure will maximize the operating range of battery-electric trucks. New, more durable batteries will also contribute to the competitiveness of battery-electric trucks, reducing total cost of ownership over a vehicle’s lifecycle.