| 摘要 |
PROBLEM TO BE SOLVED: To provide a novel vanadium iron composite oxide used as a positive electrode active material for nonaqueous electrolyte secondary battery, for improving the cycle life of amorphous FeVO4 . SOLUTION: This nonaqueous electrolyte secondary battery uses a positive electrode, containing Fe, V, and O with 25<X and 0<Y<35, when setting the contents of Fe and V to X and Y (wt.%), respectively, where a diffraction angle 2 shows main diffraction peaks in the range of 26-29 deg. and 29-32 deg. in the X-ray pattern, using CuKα-line. The diffraction angle of a battery A2 as embodiment is about 28 deg. and about 30 deg. (b). The battery is inexpensive, is low in environmental load, and shows satisfactory cycle performance. |
