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Direct recycling methods offer a non‐destructive way to regenerate degraded cathode material. The materials to be recycled in the industry typically constitute a mixture of various cathode materials extracted from a wide variety of retired lithium‐ion batteries. Bridging the gap, a direct recycling method using a low‐temperature sintering process is reported. The degraded cathode mixture of LMO (LiMn2O4) and NMC (LiNiCoMnO2) extracted from retired LIBs was successfully regenerated by the proposed method with a low sintering temperature of 300°C for 4 h. Advanced characterization tools were utilized to validate the full recovery of the crystal structure in the degraded cathode mixture. After regeneration, LMO/NMC cathode mixture shows an initial capacity of 144.0 mAh g−1and a capacity retention of 95.1% at 0.5 C for 250 cycles. The regenerated cathode mixture also shows a capacity of 83 mAh g−1at 2 C, which is slightly higher compared to the pristine material. As a result of the direct recycling process, the electrochemical performance of degraded cathode mixture is recovered to the same level as the pristine material. Life‐cycle assessment results emphasized a 90.4% reduction in energy consumption and a 51% reduction in PM2.5 emissions for lithium‐ion battery packs using a direct recycled cathode mixture compared to the pristine material.
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Cold Sintering Enables the Reprocessing of LLZO‐Based Composites
Abstract All‐solid‐state batteries have the potential for enhanced safety and capacity over conventional lithium ion batteries, and are anticipated to dominate the energy storage industry. As such, strategies to enable recycling of the individual components are crucial to minimize waste and prevent health and environmental harm. Here, we use cold sintering to reprocess solid‐state composite electrolytes, specifically Mg and Sr doped Li7La3Zr2O12with polypropylene carbonate (PPC) and lithium perchlorate (LLZO−PPC−LiClO4). The low sintering temperature allows co‐sintering of ceramics, polymers and lithium salts, leading to re‐densification of the composite structures with reprocessing. Reprocessed LLZO−PPC−LiClO4exhibits densified microstructures with ionic conductivities exceeding 10−4 S/cm at room temperature after 5 recycling cycles. All‐solid‐state lithium batteries fabricated with reprocessed electrolytes exhibit a high discharge capacity of 168 mA h g−1at 0.1 C, and retention of performance at 0.2 C for over 100 cycles. Life cycle assessment (LCA) suggests that recycled electrolytes outperforms the pristine electrolyte process in all environmental impact categories, highlighting cold sintering as a promising technology for recycling electrolytes.
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- Award ID(s):
- 2134643
- PAR ID:
- 10521847
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- ChemSusChem
- Volume:
- 17
- Issue:
- 13
- ISSN:
- 1864-5631
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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