Résumé
This poster will present the European ERA-MIN3 funded 2BoSS project [1]. In 2BoSS, we aim at validating a silicon-sulfur lithium-ion battery compatible with the circular economy, designed to minimize the use of CRMs while keeping reliable performances and enabling a circular use of material resources. We work out effective recycling strategies for the separation and reuse of raw materials from the 2BoSS battery, and implement eco-design in the choice of metal additives in the active materials in this aim. Finally, the consortium assesses cost, life cycle and environmental, health and safety impact in the perspective of a scaled-up manufacturing.It is important to assess all impacts to help guiding sustainable and circular design of technologies in the early stages of development. The tool used to analyse environmental and social impacts here is Life Cycle Assessment (LCA). Life Cycle Inventories representative of future possible industrial production are being built starting from data collected at the laboratory scale in the consortium. These datasets are to be shared with the scientific community through the Life Cycle Data Network of the EU Platform on Life Cycle Assessment.To host the sulfur within a carbon framework in the cathode of the 2BoSS battery, we use a porous carbon matrix derived from the calcination of agricultural biomass waste. Sulfur is loaded in the porous carbon by ball milling, a scalable and solvent-free process. The matrix is optimized for high electrical conductivity, high porosity and surface area. It is also loaded with a polysulfide-reduction catalyst to avoid sulfide shuttling in the battery. The anode active material is a silicon-carbon composite obtained by growing silicon nanowires either onto porous carbon from biomass or onto recycled graphite from used batteries. A high loading of silicon (>15%) ensures a high energy density [2]. The poster will discuss how to optimize lithium availability in the battery by prelithiation, and how to assemble the cell with an electrolyte compatible with both sulfur- and silicon-based electrodes, as these active materials are highly demanding towards electrolyte composition.In 2BoSS, circularity is a key aspect of the project. Recycling lithium-sulfur batteries represents a significant step forward in the field of energy sustainability. While the recycling of lithium-ion batteries is commonplace, that of lithium-sulfur batteries remains a challenge. Unlike other battery types, they do not contain precious materials such as cobalt, which can limit the perceived benefits of recycling. However, the importance of considering recycling from the battery design and production phase is undeniable to ensure a complete and sustainable life cycle. The high content in silicon is also a challenge for lixiviation methods. Aiming at circularity, we also focus on responsible sourcing of key inputs to fabricate the battery. We maximize the use of recycled materials such as recycled graphite, organic waste from winery, sulfur from oil refining processes, silicon as a byproduct of alloys production, copper, steel, and aluminum foil from suppliers employing a high percentage of secondary raw materials in a commitment to decarbonize their smelting processes. The value chain of 2BoSS diversifies raw materials sourcing and improves resource efficiency (including recycling), while reducing dependency, thereby promoting the production and export of a post lithium battery cell with a value chain made in Europe.