8 a negative slurry was prepared by dispersing the mixture into nmp the slurry was coated on a copper foil in a thickness of 15 u03bcm dried and compressed thereby manufacturing a negative electrode together with a 25 u03bcm thick polyethylene separator the manufactured electrodes were wound and pressed then placed into prismatic cans having the dimensions of 30 mm u00d7 48 mm u00d7 6 mm each electrolyte of examples 1 to 18 and comparative example 1 was injected into individual cans thereby completing the fabrication of the li ion cells the lithium ion cells which were manufactured by injecting the electrolytes of examples 1 to 18 and comparative example 1 were charged with a current of 160 ma to a charge voltage of 4 2 v under constant current and constant voltage cc cv then the cells were allowed to sit for 1 hour and the cells were discharged at 2 5 v with a current of 160 ma and left to sit for 1 additional hour after repeating this procedure 3 times the cells were charged with a current of 800 ma to a voltage of 4 2 v for 2 hours and 30 minutes after charging the cells were placed in a condenser at u2212 20 u00b0 c and they were allowed to stand for 16 hours then the cells were discharged with a current of 160 ma to a charge voltage of 2 75v in order to measure the discharge capacity of the cells the discharge.