Page 47 - European Energy Innovation - spring 2019 publication

Spring 2019 European Energy Innovation 47

COMMUNICATION

HELIS project

High energy lithium sulphur cells and batteries

By Dr Sara Drvarič Talian and Prof Robert Dominko

Lithium sulphur batteries are a viable candidate
for commercialisation of post Li-ion battery
technologies due to their high theoretical energy
density and cost effectiveness. Despite many
efforts, there are remaining issues that need to be solved,
providing the direction of lithium sulphur batteries'
technological development.

Instability of the lithium metal in most conventional with improvements suggested from research on the
electrolytes and formation of dendrites due to uneven materials development. More specifically, larger quantities
distribution of lithium upon the deposition causes several of novel carbon host matrices were produced, providing
difficulties. Safety problems connected with dendrites materials with characteristics required for production
and low coulombic efficiency with a constant increase of of prototype cells, while different analytical techniques
inner resistance due to electrolyte degradation represent were used for determination of favourable electrolyte
main technological challenges. From this point of view, composition. Several approaches for lithium metal
stabilization of the lithium metal has an impact on safety protection against continuous degradation by modification
issues. A stabilized interface layer is important from of Li metal surface or separator were proposed and
the view of engineering of the cathode composite and evaluated. The materials and components development
separator porosity since this is an important parameter was continuously supported by multiscale modelling of
for electrolyte accommodation and volume expansion cell operation.
adjustment. Finally the mechanism of lithium sulphur
batteries ageing can determine the practical applicability On the battery pack level, a battery management system
of the batteries in different applications. (BMS) was developed and the lithium sulphur cells
assessed through several safety tests. A life-cycle analysis
The HELIS project (funded through European Union's was conducted, while also an efficient recycling process
Horizon 2020 research and innovation programme under of Li-S batteries was developed in order to meet the
Grant Agreement No. 666221) is addressing the remaining European legislative requirements and the economic
issues connected with the stability of lithium anode during expectations of industry and consumers.
cycling, engineering of the complete cell and questions
about lithium-sulphur batteries cell implementation into Together, the project resulted in 9 open access
commercial products. The consortium involves a joint publications and few patent applications. The public
collaboration with multi-disciplinary and complementary deliverables and scientific publications that derive
experts coming from 14 partners and 7 different countries: directly from the outputs of the project are available and
Slovenia, France, Sweden, Germany, Finland, Spain and downloadable at https://www.helis-project.eu/. l
Israel.

The work in the project is divided into 10 work packages
and bundled into three major activities:

• coordination, management and dissemination
• lithium sulphur cell raw and advanced materials

development, testing, scale up and modelling
• cell and battery pack characterisation together with

research of ageing, safety and recycling.

The 4-year long project is finishing in May 2019. Before Acknowledgement: HELIS project has received
the end of the activities, three different series of lithium funding through the European Union's Horizon 2020
sulphur cell prototypes will have been produced, each research and innovation program under (Grant
Agreement No. 666221)
www.europeanenergyinnovation.eu