Abstract: This invention relates to a nonaqueous electrolytic solution including a lithium salt and an organic solvent containing: a carbonate and/or an ester in a total proportion exceeding 90% by volume; and a fluorine-substituted aromatic ester represented by formula (I) in an amount of 0.01%-10% by weight based on the weight of the electrolytic solution: Xn-Ph-OCOR??(1). The invention also relates to a nonaqueous electrolytic solution including an electrolyte, a nonaqueous solvent, and a compound represented by formula (3): The invention also relates to a nonaqueous-electrolyte battery including a nonaqueous electrolytic solution as described above.

Abstract: A non-aqueous liquid electrolyte suitable for use in a non-aqueous liquid electrolyte secondary battery comprising a negative electrode and a positive electrode, capable of intercalating and deintercalating lithium ions, and the non-aqueous liquid electrolyte, the negative electrode containing a negative-electrode active material having at least one kind of atom selected from the group consisting of Si atom, Sn atom and Pb atom, wherein the non-aqueous liquid electrolyte comprises a carbonate having at least either an unsaturated bond or a halogen atom.

Abstract: A non-aqueous liquid electrolyte suitable for use in a non-aqueous liquid electrolyte secondary battery comprising a negative electrode and a positive electrode, capable of intercalating and deintercalating lithium ions, and the non-aqueous liquid electrolyte, the negative electrode containing a negative-electrode active material having at least one kind of atom selected from the group consisting of Si atom, Sn atom and Pb atom, wherein the non-aqueous liquid electrolyte comprises a carbonate having at least either an unsaturated bond or a halogen atom.

Abstract: A nonaqueous electrolyte secondary battery includes a positive electrode having a positive-electrode active material, a negative electrode having a negative-electrode active material, and a nonaqueous electrolytic solution having a nonaqueous solvent dissolving a solute. The negative-electrode active material includes powdered silicon and/or a silicon alloy, the nonaqueous electrolytic solution includes additives composed of at least one fluorinated lithium phosphate selected from the group consisting of lithium monofluorophosphate, lithium difluorophosphate, and lithium trifluorophosphate and a diisocyanate compound, and the nonaqueous solvent includes a chain carbonate compound.

Abstract: A nonaqueous electrolytic solution effective in improving cycle characteristics and used for a nonaqueous electrolyte secondary battery including a positive electrode having a positive-electrode active material capable of storing and releasing metal ions and a negative electrode having a negative-electrode active material containing at least one atom selected from the group consisting of Si, Sn, and Pb includes an electrolyte, a nonaqueous solvent, and an isocyanate compound having at least one aromatic ring in its molecule.

Abstract: An object is to provide a nonaqueous electrolyte and a nonaqueous-electrolyte secondary battery which have excellent discharge load characteristics and are excellent in high-temperature storability, cycle characteristics, high capacity, continuous-charge characteristics, storability, gas evolution inhibition during continuous charge, high-current-density charge/discharge characteristics, discharge load characteristics, etc. The object has been accomplished with a nonaqueous electrolyte which comprises: a monofluorophosphate and/or a difluorophosphate; and further a compound having a specific chemical structure or specific properties.

Abstract: A subject is to provide a nonaqueous electrolyte excellent in cycle performances such as capacity retention after cycling, output after cycling, discharge capacity after cycling, and cycle discharge capacity ratio, output characteristics, high-temperature storability, low-temperature discharge characteristics, heavy-current discharge characteristics, high-temperature storability, safety, high capacity, high output, high-current-density cycle performances, compatibility of these performances, etc. Another subject is to provide a nonaqueous-electrolyte secondary battery employing the nonaqueous electrolyte. The subjects have been accomplished with a nonaqueous electrolyte which contains a monofluorophosphate and/or a difluorophosphate and further contains a compound having a specific chemical structure or specific properties.

Abstract: A nonaqueous electrolytic solution that can provide a high energy density nonaqueous electrolyte secondary battery having a high capacity, excellent storage characteristics, and excellent cycle characteristics and suppressing the decomposition of an electrolytic solution and the deterioration thereof when used in a high-temperature environment includes an electrolyte, a nonaqueous solvent, and a compound represented by general formula (1): wherein R1, R2, and R3 each independently represent a hydrogen atom, a cyano group, or an optionally halogen atom-substituted hydrocarbon group having 1 to 10 carbon atoms, with the proviso that R1 and R2 do not simultaneously represent hydrogen atoms.

Abstract: A non-aqueous liquid electrolyte secondary battery using negative-electrode active material having Si, Sn and/or Pb, with high charge-capacity, superior characteristics including discharge-capacity retention rate over long is provided. Its non-aqueous liquid electrolyte contains carbonate having unsaturated bond and/or halogen and compounds like LiPF6 and/or LiBF4 (first lithium salt) and lithium salt different from said first one, represented by formula below (second lithium salt).