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Abstract Achieving durable lithium (Li) metal anodes in liquid electrolytes remains challenging, primarily due to the instability of the formed solid‐electrolyte interphases (SEIs). Modulating the Li‐ion solvation structures is pivotal in forming a stable SEI for stabilizing Li metal anodes. Here a strategy is developed to fine‐tune the Li‐ion solvation structures through enhanced dipole–dipole interactions between the Li‐ion‐coordinated solvent and the non‐Li‐ion‐coordinating diluent, for creating a stable SEI in the developed binary salt electrolyte. The enhanced dipole–dipole interactions weaken the coordination between Li‐ions and the solvents while strengthening the interaction between Li‐ions and dual anions, thereby facilitating the Li‐ion transport and a robust anion‐derived SEI with a distinct bilayer structure. Consequently, the developed electrolyte exhibited exceptional electrochemical performance in high energy‐density Li||LiNi0.8Mn0.1Co0.1O2 (NMC811) cells, with long calendar life, stable cyclability at 1 C, and reliable operation between 25 and −20 °C, and it also demonstrat remarkable cycling stability for a Li||NMC811 pouch cell with projected energy density of 402 Wh kg−1, maintaining 80% capacity retention over 606 cycles under practical conditions.
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Methodological Studies of the Mechanism of Anion Insertion in Nanometer‐Sized Carbon Micropores
Abstract Dual‐ion hybrid capacitors (DIHCs) are a promising class of electrochemical energy storage devices intermediate between batteries and supercapacitors, exhibiting both high energy and power density, and generalizable across wide chemistries beyond lithium. In this study, a model carbon framework material with a periodic structure containing exclusively 1.2 nm width pores, zeolite‐templated carbon (ZTC), was investigated as the positive electrode for the storage of a range of anions relevant to DIHC chemistries. Screening experiments were carried out across 21 electrolyte compositions within a common stable potential window of 3.0–4.0 V vs. Li/Li+to determine trends in capacity as a function of anion and solvent properties. To achieve fast rate capability, a binary solvent balancing a high dielectric constant with a low viscosity and small molecular size was used; optimized full‐cells based on LiPF6in binary electrolyte exhibited 146 Wh kg−1and >4000 W kg−1energy and power densities, respectively.
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- Award ID(s):
- 2034110
- PAR ID:
- 10398174
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- ChemSusChem
- Volume:
- 16
- Issue:
- 4
- ISSN:
- 1864-5631
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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