For space missions, a reduction of spacecraft mass is usually directly correlated with a decrease in total mission cost and may additionally be the key enabling factor for ambitious mission concepts. As spacecraft batteries can constitute a significant part of total spacecraft mass, improving their energy density is critical.
The solutions most widely in use today are based on Lithium-Ion technology. In the future, Lithium-Sulphur technology could enable the production of batteries with an energy density twice as large as Li-Ion, providing a genuine disruption in the field of in-space energy storage.
Acknowledging this fact, the European Commission decided to fund ECLIPSE, a H2020 research project (global budget: 1 M€ over a duration of 24 months) which aims at focussing research activities in Europe to ensure that the harsh environmental constraints in space are taken into account for the further improvements of Lithium-Sulphur technology.
This action is laid out on three levels:
- Cell level studies, including research on optimising the four main cells components: anode, cathode, separator and electrolyte. The ultimate goal is to achieve an energy density of 400Wh/kg compatible with common cycling profiles for spacecraft.
- Battery and encapsulation level, including prototyping and theoretical studies. The challenge here is to account for all harsh environmental constraints of space in terms of vacuum, temperature, etc.
- System level studies for further integration into satellite and launcher architectures, taking into account the economic constraints and the future technical challenges.
- Spacecraft battery mass reduction by a factor two. Cost reduction at all spacecraft levels: subsystem, system as well as launch costs.
- Consolidation of an independent European industrial supply chain for Lithium-Sulphur batteries
- An increased maturity of the technology with the goal of achieving TRL 5 at the end of the project.
The impact of the project is ensured by the composition of the consortium, led by Airbus Defence & Space and involving the main European actors of the Lithium-Sulphur electrochemistry and space batteries sectors.