An electrolyte for a lithium-ion battery includes a primary lithium salt and an organic compound composition. In some designs, the organic compound composition includes (1) fluoroethylene carbonate (FEC), (2) vinylene carbonate (VC), (3) at least one ester (ES), and (4) a nitrile additive composition (NAC) which includes at least one nitrile compound. In some designs, a mole fraction of the NAC in the electrolyte is in a range of approximately 0.1 mol. % to approximately 2.0 mol. %. In some designs, a mole fraction of the at least one ES in the electrolyte is at least approximately 35 mol. %.