Model-based optimization and life cycle analysis of battery hybrid maritime propulsion systems



Philipp Dechent

Construction planning CARL, Battery System Design and Vehicle Integration


+49 241 80 49361



The aim of the project is the economic and ecological evaluation and optimisation of the hybridisation of large maritime engines powered by e-Fuels. Although the use of e-Fuels can minimise the emission of pollutants over the entire chain from energy production to the provision of traction power, emissions still occur locally when fuel is burned. Therefore, the reduction potential of these local emissions by hybridisation of large engines with battery storage systems will be analysed. The investigations carried out for this purpose concentrate on the application cases "Plug-In Ferry" and "Hybrid Tugboat", which are particularly suitable for hybridisation due to the rapidly changing load requirements and standby phases.

To enable such an analysis, the first step is to determine a battery cell that is suitable for maritime applications. This is then analysed and characterised. For this purpose, procedures from the field of cell characterization for stationary and automotive applications are adopted and adapted to the specific requirements of large engines with synthetic fuels for maritime applications. Here, among other things, the requirements for the dynamics of the model as well as the type of use and the resulting ageing can differ from previous application scenarios.

In addition, an optimal interaction between the marine engine and battery storage must be ensured in the design simulation in order to determine the optimum battery size. Therefore, an operating strategy for the battery storage unit is being developed which can be integrated into the design simulation of. This algorithm evaluates different operating points of the battery ac-cording to ecological and economical aspects. Thus, each use of the battery causes a degradation, which is mapped by the ageing model of the battery. This degradation has to be weighed against the benefits of using the storage to enable an ideal operating strategy.

Finally, the life cycle impacts of the storage facility are determined in a life cycle analysis. Energy expenditure for the production of the storage facility, as well as for operation and disposal, is determined and systematically analysed with regard to various impact categories. In this way, it can be determined whether the use of a storage facility leads to a reduction in emissions over its entire service life. In addition, the influences of various boundary conditions, such as the electricity mix used in the manufacture of the system, can be quantified in order to be able to assess the suitability of a battery storage unit in the applications mentioned above.



01st October 2018 – 30th September 2021




The E2Fuels project is funded by the Federal Ministry of Economics and Energy (BMWi) under the funding code 03EIV011F as part of the research initiative "Energiewende im Verkehr".

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