Attaining substantial areal capacity (>3 mAh/cm2) and extended cycle longevity in all–solid-state lithium metal batteries necessitates the implementation of solid-state electrolytes (SSEs) capable of withstanding elevated critical current densities and capacities. In this study, we report a high-performing vacancy-rich Li9N2Cl3SSE demonstrating excellent lithium compatibility and atmospheric stability and enabling high–areal capacity, long-lasting all–solid-state lithium metal batteries. The Li9N2Cl3facilitates efficient lithium-ion transport due to its disordered lattice structure and presence of vacancies. Notably, it resists dendrite formation at 10 mA/cm2and 10 mAh/cm2due to its intrinsic lithium metal stability. Furthermore, it exhibits robust dry-air stability. Incorporating this SSE in Ni-rich LiNi0.83Co0.11Mn0.06O2cathode-based all–solid-state batteries, we achieve substantial cycling stability (90.35% capacity retention over 1500 cycles at 0.5 C) and high areal capacity (4.8 mAh/cm2in pouch cells). These findings pave the way for lithium metal batteries to meet electric vehicle performance demands.
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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:
- 10502867
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- ChemSusChem
- ISSN:
- 1864-5631
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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