Whether for on-board computers, control systems, sensors and cameras or scientific experiments, satellites need a lot of energy. If the sun shines on the satellite, solar cells generate this energy. If it is in the shadow of the earth, batteries provide the necessary electrical power.
Like all components for space travel, these batteries must function extremely safely and reliably. Accordingly, they are often extensively and cost-intensively tested for several years prior to their use. Scientists from the German Aerospace Center (DLR) are working on the new research project DLRbat to reduce the test effort and thus the costs and thus to bring satellites faster and cheaper into space.
View the entire value chain
The special feature of the project: it covers the entire value chain – from the electrochemical basics to the actual application in satellites. To this end, five DLR institutes from the research areas of space and energy are contributing their competencies. The Institute for Technical Thermodynamics develops battery systems and the required control electronics. Since the weight factor is a decisive criterion in space travel, the Institute for fiber composite light construction and adaptronics works on a very light and at the same time very stable battery structure, which holds the individual battery cells together.
The Institute for System Dynamics and Control Engineering has introduced its expertise in the simulation of energy systems, While the Institute for Optical Sensor Systems is researching how supercomponents can be used to provide very high performance in the satellite at short notice. The Institute of Space Systems has facilities to perform space-specific tests. These simulate, for example, the strong vibrations at the start of a rocket or the conditions in the vacuum.
Cost advantages through virtual battery development
While many structures for aircraft, such as wings, are already designed and tested virtually on a computer, battery systems for space travel still have to be tested in the laboratory or on test stands by means of very complex procedures.
If we are able to develop a similar process for batteries, that is to say, reliably replicate the entire value chain from material development to application using computer simulation, we create a high scientific value and save time and money,
says Prof. André Thess, Director Of the DLR Institute for Technical Thermodynamics.
Battery technology of the next generation
Another key topic in the “DLRbat” project are future-oriented lithium-sulfur and lithium-air batteries. These technologies have the potential to store twice as much energy as the previously used lithium-ion batteries. They will therefore be of great importance for applications in aerospace and ground-based transport. In addition to the general requirements for these batteries of the next generation, the challenges arising from the extreme conditions in space travel, such as vacuum and radiation, are also to be examined in the project.
Within the scope of the DLR satellite mission “S2TEP” (Small Satellite Technology Platform) planned for the year 2019, the performance of a corresponding battery is to be tested extensively.