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The two new phosphates, DMMEMP and DEMEMP containing ethylene oxide (EO) have been synthesized and used as co-solvents respectively mixed with ethylene carbonate (EC) and dimethyl carbonate (DMC). The flammability of the new ternary electrolytes was examined by measuring the self-extinguishing time of electrolytes. As the content of DMMEMP or DEMEMP in the mixture reaches 30 wt%, no flammability is observed. The electrochemical test results indicate that the ternary electrolytes dissolving 1.0 M lithium bis(trifluoromethanesulfonyl)imide(LiTFSI) have good thermal stabilities, wide electrochemical windows and high conductivities. The Li/LiFePO 4 half-cells using the electrolyte show good charge-discharge performances and cycle stabilities.With the increasing demands for rechargeable lithium ion batteries applications, especially in electric vehicle (EV) and hybrid electric vehicle (HEV), 1 there are growing concerns about the safety limitations of conventional electrolytes. Since the safety is usually considered to be associated with the combination of the highly reactive electrode materials and the highly flammable components in the electrolyte, 2,3 many attempts have been made in recent years to obtain nonflammable or at least retarded flammable electrolytes by using safer and more stable solvents as flame-retarding additives or co-solvents. [4][5][6][7][8][9] Up to the present, varieties of fire-retardant compounds have been investigated, mainly involving organic phosphates, 10-13 organic halogens 14-17 and ionic liquids. [18][19][20][21] With the application of flame retardants, the safety of lithium ion batteries could be improved but the batteries suffer from severe capacity fading and hence most of the organic phosphates have to be used in low concentrations, usually no more than 20% either by weight or by volume. For example, the performance of electrolyte containing 20% trimethyl phosphate (TMP) shows steep capacity fading. As triethyl phosphate (TEP) > 20%, the capacity utilization will be reduced with the viscosity increasing, and the rate of capacity fading is proportional to TEP contents. 22,23 In previous study, we reported that the ethylene oxide (EO)-containing phosphate could be used as a single nonflammable electrolyte solvent for lithium ion batteries. 24 Whereas, lithium-ion battery electrolytes are mostly composed of two or more solvents owning to the diverse requirements of battery applications which cannot be met by any individual solvent. 25 Under such circumstances, it is important to develop either the electrolyte solvents with higher flame-retardant efficiency, or the new solvents which could be used in high content with little negative effects.In this paper, a new class of ethylene oxide (EO)-containing phosphates (DMMEMP and DEMEMP) as the co-solvent mixed with the commercial carbonate electrolytes have been investigated because of their advantages of moderate viscosity (4.85 and 3.60 mPa s), high boiling point (280 and 310 • C) and good nonflammability. In addition, the feasibility of...

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We report the successful manufacture of several >50 kg batches of a key intermediate via a Birch reduction that utilized liquified ammonia as well as lithium metal. With an eye toward continued scalability, we explored two alternative procedures to obtain the same intermediate: (1) an electrochemical reduction performed using continuous flow technology and (2) a ketalization approach that proceeds with olefin migration to give the target molecule. Both options were explored in detail and then demonstrated on a ≥100 g scale to assess the overall robustness. Ultimately, the olefin migration route appeared to be more promising and was demonstrated on a >1 kg scale to show the potential to avoid several unattractive aspects of the Birch reduction for future scale-up needs.