NOVELTY - A positive electrode and a negative electrode are prepared (S10), in which an sodium component is contained in the positive electrode or negative electrode as an unavoidable impurity, and an electrode component (S20) is formed using the prepared positive and negative electrodes. An assembly is formed (S30) in which the electrode component is contained in a battery case, a nonaqueous electrolyte solution is injected (S40) into the battery case, and assembly is charged and discharged (S50), to obtain nonaqueous-electrolyte secondary battery.    USE - Manufacture of nonaqueous-electrolyte secondary battery (claimed) used as power supply for hybrid vehicle, fuel motor vehicle, electric vehicle, portable terminal and personal computer.    ADVANTAGE - The nonaqueous-electrolyte secondary battery is efficiently manufactured with suppressed precipitation of sodium diboron carbon oxide and increase in battery resistance, and excellent battery performance.    DETAILED DESCRIPTION - A positive electrode and a negative electrode are prepared, in which an sodium component is contained in the positive electrode or negative electrode as an unavoidable impurity, and an electrode component is formed using the prepared positive and negative electrodes. An assembly is formed in which the electrode component is contained in a battery case, a nonaqueous electrolyte solution is injected into the battery case, and assembly is charged and discharged, to obtain nonaqueous-electrolyte secondary battery. The nonaqueous electrolyte solution contains lithium bis(oxalato)borate, a fluorine-containing phosphoric acid compound, a carbonate solvent and an ether solvent. The negative electrode contains negative electrode active material. The positive electrode contains a positive electrode active material. The content of ether solvent is contained in the nonaqueous electrolyte solution is less than 10 volume% when the amount of the nonaqueous solvents contained in the nonaqueous electrolyte solution is 100 volume%. An INDEPENDENT CLAIM is included for non-aqueous-electrolyte secondary battery.    DESCRIPTION OF DRAWING(S) - The drawing shows the flowchart explaining the manufacture of nonaqueous-electrolyte secondary battery. (Drawing includes non-English language text)    Positive negative electrode preparatory process (S10)    Electrode component preparation process (S20)    Assembly preparation process (S30)    Injecting process (S40)    Charge-and-discharge process (S50)