Gut microbiota-driven, acid-free recovery and upcycling of spent lithium-ion battery cathodes

Gut microbiota-driven, acid-free recovery and upcycling of spent lithium-ion battery cathodes | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Article Gut microbiota-driven, acid-free recovery and upcycling of spent lithium-ion battery cathodes Chong S. Yoon, Min Li, Danni Zhang, Di Na, Pan Liu, Qiuli Xia, and 7 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8784799/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract The sustainability of lithium-ion battery recycling faces challenges due to the heavy reliance on corrosive acids in hydrometallurgy and traditional bioleaching. Here, a neutral-pH bio-metallurgical process using gut microbiota is reported for leaching spent Li(Ni0.5Co0.2Mn0.3)O2 cathodes. Under facultative anaerobic conditions, the microbial community adapts to enrich metal-tolerant and electroactive groups (e.g., Actinobacteriota, Desulfobacterota_I), allowing metal release through direct contact and extracellular electron transfer. Riboflavin, a known electron shuttle, improves yields to 99.3% for Li and 93.3% for Ni when supplemented. Significantly, the process leads to different fates for metal ions: Li and Ni remain soluble, while Co and Mn are reduced to form NH4(Co,Mn)PO4·H2O precipitates. This in situ phase separation simplifies downstream purification. The phosphate residues show excellent electrochemical performance, with a capacitance of 168 mF·cm−2 as supercapacitor electrodes. This method presents a green, robust, and adaptable approach for critical metal recycling. Earth and environmental sciences/Environmental sciences/Environmental impact Physical sciences/Materials science/Materials for energy and catalysis/Batteries Physical sciences/Materials science/Biomaterials/Biomineralization Biological sciences/Biotechnology/Environmental biotechnology Bioleaching Gut microbiota Spent lithium-ion battery Neutral pH Riboflavin Secondary minerals Metal recovery Full Text Additional Declarations There is NO Competing Interest. Supplementary Files SupplementaryInformation.pdf Gut microbiota-driven, acid-free recovery and upcycling of spent lithium-ion battery cathodes Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-8784799","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":588879816,"identity":"8c532ae1-7ae3-4e1f-acd3-e10511a651c7","order_by":0,"name":"Chong S. 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