US Patent 6924061 Nonflammable non-aqueous electrolyte and non-aqueous electrolyte cells comprising the same

A non-aqueous electrolyte to be used in a Li-ion battery includes a lithium salt, a cyclic carbonate, a linear carbonate and an alkyl fluorinated phosphate, of the following general formulawherein R1, R2 and R3, independently, are selected from the group consisting of straight and branched alkyl groups having 1-5 carbon atoms, and at least one of said alkyl groups is fluorinated, with the locations of said fluorination being at least β-positioned away from the phosphorous of said phosphate, such that said alkyl phosphate has a F/H ratio of at least 0.25, and said electrolyte solution is non-flammable.