Fabrication and electrochemical characterization of lithium metal battery using IL-based polymer electrolyte and Ni-rich NCA cathode

Electrolytes with high Li+ transference number and good electrochemical stability are urgently needed for high-energy-density Li battery. In this paper, we present newly synthesized ionic liquid (IL)-based polymer electrolyte using polymer poly(ethylene oxide) (PEO), salt lithium bis(fluorosulfonly)imide (LiFSI), and IL 1-butyl-3-methylpyridinium bis(trifluoromethylsulfonyl)imide (BMPyTFSI) by solution cast technique. They show high Li+ transference number and good electrochemical and thermal stability. Also, nickel-rich layered cathode material LiNi0.90Co0.05Al0.05O2 (NCA) with good electrochemical performance for lithium secondary battery is successfully synthesized by Co-precipitation method. Using the optimized polymer electrolyte and NCA cathode, Li cell is prepared which shows initial discharge capacity of ~ 137 mAh g−1 at 0.1 C-rate and good Coulombic efficiency ~96.0% upto 125 cycles.