| 摘要 |
The present invention relates to a positive electrode for a lithium ion secondary battery, a lithium ion secondary battery including the positive electrode, and a battery system including the lithium ion secondary battery and a charging and discharging controller for controlling charging and discharging of the battery by voltage. The positive electrode includes a positive electrode active material (A) of LiFePO4 with an olivine structure and a positive electrode active material (B) represented by general formula yLi2MnO3·(1-y)LiMO2 (y is 0.3<=y<=0.7, and M is two or more elements selected from Co, Mn, Ni, Fe, and Ti, and the sum of valances of selected elements is 3). The weight ratio of the positive electrode active material (A) to the positive electrode active material (B) is 80-90 wt%. [Reference numerals] (AA) Voltage(V) |
