Identification of target materials for recycling of solid-state batteries from environmental and economic perspective using information theory entropy

Solid-state batteries (SSBs) are a promising emerging battery technology for electromobility application. Along with new technical opportunities (higher energy density, lower safety risks), they introduce new cell chemistry configurations and novel materials in use. This leads to increased complexity of material composition and may reduce the recyclability of SSBs. To ensure circularity of SSB materials, it is important to consider their recyclability at the early stage of SSB development. This paper proposes an approach for identification of target materials for recycling within three types of SSBs with polymer, oxide and sulfide electrolytes. To consider environmental and economic perspectives, interdependencies of material dilution, their cost and environmental material footprint are analyzed using Sherwood and global warming potential (GWP)-plots. Furthermore, a socio-geopolitical aspect of supply risk is considered as a relevant criterion for targeting materials. Li is identified as the main target material for all considered SSBs and Co as a further one for oxide- and sulfide-based cells. Furthermore, an upscaling scenario to a battery pack considered changes in concentration of target materials and revealed direct recycling of composite cathode LLZO and LCO to be very beneficial. Results of this approach can be used by SSB developers and recyclers in order to strive for holistic design enabling recycling of identified target materials.