| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a lithium secondary battery using a nonaqueous electrolyte solution capable of improving discharge characteristics at a large current. <P>SOLUTION: The lithium secondary battery 20 is provided with an electrode group with a positive electrode plate 1 and a negative electrode plate 2 wound around through a separator 3. The electrode group is housed in a battery container 6. The nonaqueous electrolyte solution is injected into the battery container 6. The nonaqueous electrolyte solution has an organic compound having a phosphorus-oxygen double bond and lithium salt both dissolved in organic solvent. The organic compound has: one phosphorus atom; one oxygen atom double-bonded to the phosphorus atom; and three substituents bonded to the phosphorus atom. Each of the three substituents has the carbon number of 1 to 10, has at least one oxygen atom and that has at least one out of atoms of elements of hydrogen, sulfur, oxygen, nitrogen, fluorine, chlorine, bromine and iodine. As the lithium salt, LiBF<SB>4</SB>is used. Thus, ion conductivity of the nonaqueous electrolyte solution is improved. <P>COPYRIGHT: (C)2011,JPO&INPIT |
