An investigation of alternative lithium salts, lithium tetrafluoroborate (LiBF₄), lithium difluoro(oxalato)borate (LiDFOB) and lithium hexafluorophosphate (LiPF₆), in novel ester-based (methyl acetate/fluoroethylene carbonate- MA/FEC or methyl propionate/fluoroethylene carbonate- MP/FEC) electrolyte formulations has been conducted in LiNi_0.6Co_0.2Mn_0.2O₂ (NCM622)/graphite cells to improve low temperature cycling performance of lithium ion batteries at −20 °C. Improved low temperature performance was observed with all the lithium salts in MA/FEC electrolyte while comparable room temperature (25 °C) capacities were observed with LiPF₆ salt only. Detailed ex-situ analysis of surface films generated with LiBF₄, LiDFOB and LiPF₆ in ester-based electrolytes reveals that the solid electrolyte interphase (SEI) is predominately composed of lithium salt decompaction products and addition of 10% FEC (by volume%) may not be sufficient at forming a protective SEI.