Highlights A novel amide-based nonflammable electrolyte is proposed. The formation mechanism and solvation chemistry are investigated by molecular dynamics simulations and density functional theory. An inorganic/organic-rich solid electrolyte interphase with an abundance of LiF, Li3N and Li–N–C is in situ formed, leading to spherical lithium deposition. The amide-based electrolyte can enable stable cycling performance at room temperature and 60 ℃. Abstract The formation of lithium dendrites and the safety hazards arising from flammable liquid electrolytes have seriously hindered the development of high-energy-density lithium metal batteries. Herein, an emerging amide-based electrolyte is proposed, containing LiTFSI and butyrolactam in different molar ratios. 1,1,2,2-Tetrafluoroethyl-2,2,3,3-tetrafluoropropylether and fluoroethylene carbonate are introduced into the amide-based electrolyte as counter solvent and additives. The well-designed amide-based electrolyte possesses nonflammability, high ionic conductivity, high thermal stability and electrochemical stability (> 4.7 V). Besides, an inorganic/organic-rich solid electrolyte interphase with an abundance of LiF, Li3N and Li–N–C is in situ formed, leading to spherical lithium deposition. The formation mechanism and solvation chemistry of amide-based electrolyte are further investigated by molecular dynamics simulations and density functional theory. When applied in Li metal batteries with LiFePO4 and LiMn2O4 cathode, the amide-based electrolyte can enable stable cycling performance at room temperature and 60 ℃. This study provides a new insight into the development of amide-based electrolytes for lithium metal batteries.

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Itaconic acid, available in abundance from corn starch, is utilized as a high-capacity anode material for rechargeable lithium-ion batteries.

In this paper, 1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluoropropyl ether (TTE) is adopted as a bifunctional electrolyte additive, which is identified to effectively stabilize the surface for both graphite anode and LiNi 0.5 Co 0.2 Mn 0.3 O 2 (NCM523) cathode within the graphite/NCM523 full cell. The overall electrochemical performances of the full cell are significantly enhanced with 3 wt % TTE additive in a conventional organic electrolyte. A combination of studies of scanning electronic microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and Fourier transform infrared (FTIR) spectroscopy show that a uniform, compact, and stable solid electrolyte interphase (SEI) with improved mechanics on the graphite anode and an effective cathode electrolyte interphase (CEI) on the NCM523 cathode is developed. The electron-withdrawing C−F group contributes to the stable and compact surface film, which explains the electrochemical enhancement of the NCM523/ graphite full cell.

Small molecule organic acids as electrode materials possess the advantages of high theoretical capacity, low cost, and good processability. However, these electrode materials suffer from poor cycling stability due to the inevitable dissolution of organic molecules in the electrolytes. Here, a eutectic mixture of lithium bis(trifluoromethanesulfonyl)imide and N‐methylamine is employed as a eutectic electrolyte in Li‐ion batteries with small molecule organic acids as electrodes. To enhance the cycling stability of the electrolyte, fluoroethylene carbonate is used as an additive. The electrolyte exhibits nonflammability, high ionic conductivity, and good electrochemical stability. Molecular dynamics simulations and density functional theory are performed to further investigate the solvation chemistry of the eutectic electrolyte. The well‐designed eutectic electrolyte inhibits the dissolution of terephthalic acid effectively and displays superior performance with a capacity retention of ≈84% after 2000 cycles at a high current density of 1 A g−1. It also enables stable cycling of more than 900 cycles at a high current density of 2 A g−1 at 60 °C. This study provides a strategy to enhance the cycling stability and safety of Li‐ion batteries with organic electrode materials.

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