Figure 6. (A, B) Raman spectra of carbonate electrolytes with different concentration of LiPF6 and diluent and Li 1s spectra of surface of current collectors with E1 and E2 electrolytes. Reproduced with permission.[108] Copyright 2019, American Chemical Society (C,D,E) Annular bright filed scanning electron microscopy image of NCM811 cathodes before and after cycling with HCEs and LHCEs, SEM images of deposited Li metal with conventional carbonate electrolytes (1 M LiPF6 in EC-EMC (3:7 by wt.), HCE (LiFSI-1.2DME), and LHCE (LiFSI-1.2DME-3TTE) and cycling performance of Cu||NCM811 anode-free full cells with lean electrolyte and high loading cathode, 4.2 mA h cm-2 . Reproduced with permission.[42] Copyright 2019, Elsevier.
Figure 7. (A,B,C) Cu||NMC532 full-cell cycle performance of various electrolytes with modified solvents by fluorination and chain length, Rate performance of 1 M LiFSI/6FDMH-DME electrolytes and high cycle stability of anode-free Cu||NMC532 pouch cells achieving 75 % of initial capacity retention at 120 cycles. Reproduced with permission.[113] Copyright 2021, Wiley-VCH. (D) Change of C 1s spectra of SEI composition by using VC. Reproduced with permission.[128] Copyright 2017, The Electrochemical Society. (E) NO3- derived SEI layer in N 1s spectra. Reproduced with permission.[102]Copyright 2019, The Electrochemical Society. (F) Dual functional effects of KNO3 additive in stabilization of Li metal. Reproduced with permission.[132] Copyright 2019, Elsevier.