When audience takes stage: Pseudo-localized-high-concentration electrolyte with lithium nitrate as the only salt enables lithium metal batteries with excellent temperature and cathode adaptability

Bidirectional Interphase Modulation of Phosphate Electrolyte Enables Intrinsic Safety and Superior Stability for High-Voltage Lithium–Metal Batteries

“…Accompanied by the generation of 3.4% AGGs, the ratio of SSIP decreased to 55.8%, and the ratio of CIP decreased to 40.8% in the TNE electrolyte, demonstrating that introduced NO 3 − entered into the inner solvation sheath of the electrolyte. Similarly, with the addition of few DME into the TE-based electrolyte, the proportion of SSIPs decreased to 52.7% and the AGGs increased to 5.7% in the TDE electrolyte, indicating the obviously modulated coordination structure because of the In order to deeply understand the solvation structure, NMR spectra of 7 Li and 19 F were performed as well. As shown in Figure 1g, in the basic TE electrolyte, a typical 7 Li signal of the LiTFSI salt is located at δ = −1.12 ppm.…”

“…− enters the solvation structure of Li + . 32 Compared with the basic TE electrolyte, introducing DME induced an upfield shift (more negative) of the 7 Li signal in the TDE electrolyte, which manifests the increased shielding effect of DME on Li + and entered deeper solvation sheath. 33 The chemical shift of the 7 Li NMR spectrum in the TDNE electrolyte is between TNE and TDE, signifying that NO 3 − weakens the shielding effect of DME on Li + .…”

“…32 Compared with the basic TE electrolyte, introducing DME induced an upfield shift (more negative) of the 7 Li signal in the TDE electrolyte, which manifests the increased shielding effect of DME on Li + and entered deeper solvation sheath. 33 The chemical shift of the 7 Li NMR spectrum in the TDNE electrolyte is between TNE and TDE, signifying that NO 3 − weakens the shielding effect of DME on Li + . Furthermore, the 7 Li signal is still presents a downfield shift in the TDNE electrolyte compared with TE, revealing that the shielding of Li + is still decreasing, which suggests that the solvation structure formed in TDNE is looser and easier to desolvate.…”

“…33 The chemical shift of the 7 Li NMR spectrum in the TDNE electrolyte is between TNE and TDE, signifying that NO 3 − weakens the shielding effect of DME on Li + . Furthermore, the 7 Li signal is still presents a downfield shift in the TDNE electrolyte compared with TE, revealing that the shielding of Li + is still decreasing, which suggests that the solvation structure formed in TDNE is looser and easier to desolvate. 34 Then we observed the solvation structure from the perspective of F in the TFSI − (Figure 1h).…”

“…(g) Long-term cycling of Li∥NCM 622 cells using TE, TNE, TDE, and TDNE electrolytes at 1 C. (h) Rate performances in different electrolytes. (i) Comparison of Coulombic efficiency (CE), voltage, full cell lifespan, safety, flame retardant concentration, and cost of the TDNE with the state-of-the-art phosphate nonflammable electrolytes 7,9,10,[12][13][14][15]17,19,21,[23][24][25][30][31][32]34.…”