The use of thermal storages can reduce the load on the battery of electric buses in winter and thus increase their range. As part of the LatHe.GO research project, we are investigating the use of metallic latent heat storages as heating system for electric buses.
Due to their high efficiency, electric motors hardly generate any waste heat during operation. Unlike buses with combustion engines, electric buses can therefore not be heated via the engine's cooling circuit. If additional fossil-fuel heating is to be dispensed with, the energy needed to heat the electric bus must be provided by the battery. This can reduce the range by up to 50 % in winter.
One solution to the problem of range reduction is the use an additional thermal storage. This is where the LatHe.GO research project comes in: the aim of the research project is to develop and apply metallic latent heat storages for the utilization as heating system in electrified vehicles. Due to the high temperature level, these thermal storages can achieve up to 2.5 times higher storage densities than batteries.
The research project aims to extensively develop the technology of metallic latent heat storages. This includes, among other things, the development of basic principles on the materials level, the development and design of a storage system as well as the thermal and control-related integration into the vehicle. The work will culminate in an extensive experimental investigation of a functional model in a laboratory environment.
The results obtained can be used to demonstrate the potential of metallic latent heat storages as heating system in electric buses. Furthermore, the basis for further work bringing the technology closer to the market can be established. In addition to automotive applications, the basic findings on storage materials and enclosures can potentially be transferred to other industries, such as the foundry industry.
The research project LatHe.GO is a joint project of four research partners.
The DLR’s Institute of Materials Physics in Space undertakes the experimental characterization and evaluation of metallic phase change materials and potential containment materials. The DLR’s Institute of Vehicle Concepts is responsible for the development of the storage system as well as the construction and laboratory testing of a functional model. Our project partner ACCESS e.V. investigates simulatively the thermophysical influences on the storage system. We at TLK Energy are responsible for determining the vehicle-specific requirements for the storage system (e.g. heating load calculation of the vehicle cabin) as well as for its thermal and control-related vehicle integration.
The research project is supported using funds from the Europäischen Fonds für regionale Entwicklung (EFRE) 2014 -2020 „Investitionen in Wachstum und Beschäftigung“.