Lithium secondary battery
View Patent ↗A lithium secondary battery is provided with a positive electrode, a negative electrode, and a non-aqueous electrolyte prepared by dissolving a solute in a non-aqueous solvent wherein a positive electrode active material of said positive electrode is composed of lithium-manganese composite oxide having a spinel structure and lithium-transition metal composite oxide having a layer structure containing at least nickel and lithium salt having oxalato complex as anion is admixed to said non-aqueous electrolyte.
1. A lithium secondary battery provided with a positive electrode, a negative electrode, and a non-aqueous electrolyte prepared by dissolving a solute in a non-aqueous solvent, wherein
a positive electrode active material of said positive electrode is composed of lithium-manganese composite oxide having a spinel structure and lithium-transition metal composite oxide having a layer structure containing at least nickel, and
lithium salt having an oxalato complex as anion and vinylene carbonate are admixed to said non-aqueous electrolyte, wherein
said vinylene carbonate is admixed to the non-aqueous electrolyte in a range of 0.5 to 3.0 wt % based on the non-aqueous electrolyte before admixing the lithium salt having the oxalato complex as the anion thereto.
2. The lithium secondary battery according to claim 1 , wherein
said lithium salt having the oxalato complex as the anion to be admixed to the non-aqueous electrolyte is lithium bis(oxalato) borate Li[B(C 2 O 4 ) 2 ].
3. The lithium secondary battery according to claim 1 , wherein
the lithium salt having the oxalato complex as the anion is admixed to the non-aqueous electrolyte in a range of 0.01 to 0.1 mol/l based on said non-aqueous solvent in the non-aqueous electrolyte.
4. The lithium secondary battery according to claim 1 , wherein
said lithium-transition metal composite oxide having the layer structure containing at least nickel used as the positive electrode active material contains manganese.
5. The lithium secondary battery according to claim 1 , wherein
said solute in the non-aqueous electrolyte is LiPF 6 .
6. A lithium secondary battery provided with a positive electrode, a negative electrode, and a non-aqueous electrolyte prepared by dissolving a solute in a non-aqueous solvent, wherein
lithium salt having an oxalato complex as anion and vinylene carbonate is admixed to said non-aqueous electrolyte.
7. The lithium secondary battery according to claim 6 , wherein
said lithium salt having the oxalato complex as the anion to be admixed to non-aqueous electrolyte is lithium bis(oxalato) borate Li[B(C 2 O 4 ) 2 ].
8. The lithium secondary battery according to claim 6 , wherein the lithium salt having the oxalato complex as the anion is admixed to the non-aqueous electrolyte in a range of 0.01 to 0.1 mol/l based on said non-aqueous solvent in the non-aqueous electrolyte.
9. The lithium secondary battery according to claim 6 , wherein
at least one of lithium-manganese composite oxide having a spinel structure and lithium-transition metal composite oxide having a layer structure containing at least nickel is used as said positive electrode active material of the positive electrode.
10. The lithium secondary battery according to claim 6 , wherein said solute in the non-aqueous electrolyte is LiPF 6 .