Practical considerations in designing solid state Li-S cells for electric aviation

The development of high-energy, high-safety, and high-power batteries beyond electric automotive stan-dards is critical for future electric aviation applications. Non-volatile solid-state electrolytes (SSE) offer many promising advantages over traditional flammable liquid electrolytes. SSE may become an enabling technology for certain battery chemistries by preventing detrimental interactions that occur with liquid electrolytes, for example preventing dissolution of lithium-sulfur intermediates common in traditional liq-uid organic solvents. However, significant manufacturing challenges must be overcome before the adop-tion of such technology. One of the main challenges is the fabrication of sufficiently thin electrolyte layer to maximize specific energy of the solid-state cell. In this work we first show the feasibility in the as-sembly of an all solid-state battery via the development of composite SSE with ionic conductivity above 0.2mS/cm and thicknesses on the order of 40 micron through a tape-casting technique. With Li/Al al-loy as the anode and TiS2 as the active cathode material, the resultant solid-state battery with a thin electrolyte layer and excellent cathode-electrolyte interface represents a prototype vision on a potential solid-state cell required for electric aviation. A detailed parameter analysis is further presented on the influence of the various cell metrics, such as electrolyte thickness, carbon content, active material uti-lization, and excess lithium, on the cell specific energy. The implications in the optimization of these required parameters to enable practical solid-state Li-S batteries for electric aviation are discussed. Published by Elsevier Ltd.