Publikationsrepositorium - Helmholtz-Zentrum Dresden-Rossendorf

Liquid metal batteries (LMBs), built as stable density stratification of two liquid metals separated by a molten salt, are a promising electrical energy storage technology. While their operation has been proved for small prototypes, large industrial cells are not yet available. Up-scaling requires the full knowledge of the different phenomena occurring in LMBs. In this work we focus our attention on thermal phenomena, these are one of the main cause of flow inside the cell.

The system is first studied with a 0D electrochemical approach, focusing the attention on reversible and irreversible phenomena. A simple voltage model for the Li||Bi cell and the formulation of heat generation terms are proposed. From multi-physics considerations the geometrical and operating parameters are fully estimated.

Then thermal phenomena proper of LMBs are analyzed in the framework of continuum mechanics. 1D pure heat conduction models are built in order to assess the effect of different heat generation terms. Radiative heat transfer in the molten salt layer is also estimated.
Finally the VOF multiphase solver multiphaseInterFOAM is improved in order to study thermal convection in multi-layer systems. The comparison of results of our solver to the ones of a pseudo-spectral code and the first results of thermal convection in LMBs are also presented.