| 摘要 |
A secondary battery is provided. The secondary battery includes a cathode; an anode; and a non-aqueous electrolytic solution, wherein the cathode includes any one of a first lithium-containing compound and a second lithium-containing compound, the first lithium-containing compound having a bedded salt-type crystal structure, wherein the first lithium-containing compound includes one or more metal elements (M) other than lithium (Li), wherein the second lithium-containing compound having an olivine-type crystal structure, and wherein the nonaqueous electrolytic solution includes an unsaturated cyclic compound. |
| 主权项 |
1. A secondary battery comprising:
a cathode; an anode; and a non-aqueous electrolytic solution, wherein the cathode includes any one of a first lithium-containing compound and a second lithium-containing compound, the first lithium-containing compound having a bedded salt-type crystal structure,
the first lithium-containing compound includes one or more metal elements (M) other than lithium (Li),a photoelectron spectrum of oxygen 1s associated with the first-lithium containing compound and having a horizontal axis representative of binding energy in electron volt and a vertical axis representative of spectrum intensity, the photoelectron spectrum of oxygen 1s obtained by surface analysis of the cathode with the use of X-ray photoelectron spectroscopy includes a first peak and a second peak, the first peak having an apex in a range in which binding energy is from 531 electron volts to 535 electron volts both inclusive, and the second peak having an apex in a range in which binding energy is equal to or larger than 529 electron volts and less than 531 electron volts and having spectrum intensity smaller than spectrum intensity of the first peak,when an atomic ratio (Co/M) of cobalt in the metal element is equal to or larger than 0.5, a ratio IB/IA between a spectrum intensity IA of the second peak and a spectrum intensity IB in the case where binding energy is 535 electron volts is larger than 1, andwhen the atomic ratio (Co/M) of cobalt in the metal element is less than 0.5, a ratio IC/IA between the spectrum intensity IA of the second peak and a spectrum intensity IC in the case where binding energy is 536 electron volts is larger than 1, wherein the second lithium-containing compound having an olivine-type crystal structure,
a photoelectron spectrum of oxygen 1s associated with the second lithium-containing compound and having a horizontal axis representative of a binding energy in electron volt and a vertical axis representative of a spectrum intensity, the photoelectron spectrum of oxygen 1s obtained by surface analysis of the cathode with the use of X-ray photoelectron spectroscopy includes a third peak and a fourth peak, the third peak having an apex in a range in which binding energy is equal to or larger than 530 electron volts and less than 533 electron volts, and the fourth peak having an apex in a range in which binding energy is from 533 electron volts to 536 electron volts both inclusive and having spectrum intensity smaller than spectrum intensity of the third peak, anda ratio IE/ID between a spectrum intensity ID of the third peak and a spectrum intensity IE of the fourth peak is larger than ¼; wherein the polymer compound includes a repeating unit that includes oxygen; and wherein the nonaqueous electrolytic solution includes an unsaturated cyclic compound represented by a following Formula (8), where Y is a divalent group in which p-number of >C═CR8R9 and q-number of >CR10R11 are bound in any order; each of R8 to R11 is one of a hydrogen group, a halogen group, a monovalent hydrocarbon group, a monovalent oxygen-containing hydrocarbon group, a monovalent halogenated hydrocarbon group, a monovalent halogenated oxygen-containing hydrocarbon group, and a group obtained by binding two or more of the hydrogen group, the halogen group, the monovalent hydrocarbon group, the monovalent oxygen-containing hydrocarbon group, the monovalent halogenated hydrocarbon group, and the monovalent halogenated oxygen-containing hydrocarbon group; any two or more of R8 to R11 may be bound to one another; and p and q satisfy p≧1 and q≧0. |
