Ethylene carbonate is used in virtually every lithium-ion cell.  In efforts to produce high voltage NMC/graphite cells, electrolytes without ethylene carbonate are being explored.  The use of electrolytes based on fluoroethylene carbonate (FEC), difluoroethylene carbonate (di-FEC), bis(2,2,2-trifluoroethyl) carbonate (TFEC) and other solvents are explored in this presentation.  Studies using ultra high precision coulometry, impedance spectroscopy, isothermal battery microcalorimetry, in-situ gas evolution, storage testing, XPS and long-term charge-discharge testing show the benefits and drawbacks of such electrolytes.  Although progress is being made, there remains substantial work to do to produce high energy denisty NMC/graphite cells which can operate for years to 4.5 V.   This work was done by Jian Xia, Remi Petibon, Steven Glazier, Kathlyne Nelson, Dan Abarbanel, Deijun Xiong, Leah Ellis and Alex Louli. The authors thank Xiaodong Cao of HSC Corporation for kindly providing many of the solvents used in the work.