The present application discloses a high voltage electrolyte including an electrolyte solvent which includes a mixture of a dinitrile solvent and a nitrile solvent and is stable at voltage of about 5 V or above. The dinitrile solvent may include at least one selected from the group consisting of malononitrile, succinonitrile, glutaronitrile, adiponitrile, pimelonitrile, suberonitrile, azelanitrile and sebaconitrile. The nitrile solvent may include at least one selected from the group consisting of acetonitrile, propionitrile, butyronitrile, pivalonitrile and capronitrile. The present application also discloses a lithium ion battery including the above high voltage electrolyte. The lithium ion battery exhibits a cyclic performance of greater than about 300 cycles and with a capacity retention of greater than about 80%.