Batteries are used in countless applications where off-grid electricity is needed. With the growing importance of wind and solar power, batteries will also play an important role for storing surplus power, and in the future energy system electric vehicles are expected to be much more widespread. However, compared to fossil fuels batteries can store much less energy per volume or weight. At the same time the price of batteries is relatively high. To meet the requirements of the transport sector, significant improvements in terms of energy and power density, durability, price, and safety are needed.

The research in the Department of Energy Conversion and Storage targets new battery types with improved energy density, power density, durability and stability. We develop, characterize and test novel materials, cells and battery packs, in close collaboration with national and international research institutions and industry.

Our main activities are centered on atomic-scale computational materials design, using density functional theory (DFT) simulations on supercomputers, followed by synthesis of the most promising new materials. The materials development is closely coupled to the characterization of the structural, chemical, and electrochemical properties. Characterization down to the nano- and microscale is done using international large-scale neutron and synchrotron facilities. An important aspect is the development of in situ scattering methods to study the microstructure of the materials during realistic operation conditions. Finally, the materials are integrated in battery cells and packs for testing of performance and durability using, e.g., impedance spectroscopy.

We are not only working on the development of novel materials for existing battery technologies, e.g. new cathodes and solid electrolytes for lithium-ion (and similar metal-ion) batteries, but also on emerging technologies such as next-generation metal-air and metal-sulphur batteries which have a significantly higher energy density. Potential low-cost concepts for large-scale storage like Zn-air and organic redox flow batteries are also pursued.

Important research topics include:

  • Computational design of novel battery materials and identification of fundamental mechanisms
  • Transport kinetics and degradation mechanisms limiting battery performance and durability
  • Detailed structural characterization, ex situ and in situ, using X-rays, neutron scattering and electron microscopy
  • In situ electrochemical characterization of electrodes and electrode/electrolyte interfaces
  • Performance test and characterization of battery cells, packs and modules.


Johan Hjelm
DTU Energy
+45 46 77 58 87