| 摘要 |
PROBLEM TO BE SOLVED: To provide a nonaqueous electrolyte secondary battery having sufficient stability even at high temperature during charging, and a high energy density with high voltage charging. SOLUTION: This nonaqueous electrolyte secondary battery uses a material represented with composition formula of LiCoO2 as a positive electrode active material. An X-ray diffraction analysis is conducted while LiCoO2 is made to belong to the hexagonal system. Integrated intensities corresponding to a plane 003 around 18.8 deg. and a plane 110 around 66.3 deg. indicated in a diffraction pattern are respectively referred to as I(003) and I(110). A relation represented as I(003)/I(110)<=5.6 is satisfied. LiCoO2 simultaneously satisfies relations represented as I(105)/I(103)<=0.9 and I(110)/I(113)<=1.35 when intensities corresponding to a plane 105 around 49.2 deg. and a plane 113 around 69.7 deg. indicated in the diffraction pattern are respectively referred to as I(105) and I(113). |
