POSITIVE ELECTRODE SHEET, MANUFACTURING METHOD THEREFOR, LITHIUM ION SECONDARY BATTERY, BATTERY MODULE, BATTERY PACK, AND DEVICE

This application provides a positive-electrode plate, including a current collector, and a first active substance layer and a second active substance layer that are sequentially disposed on a surface of the current collector. The first active substance layer includes a first positive-electrode active material, and the first positive-electrode active material includes at least one of a compound represented by Formula (I) Li1+x1Mna1M1-a1O2-y1Ay1 or a compound represented by Formula (II) Li1+x2Mna2N2-a2O4-y2By2. The second active substance layer includes a second positive-electrode active material having a pH value of from 10~12. In this application, the active substance layer that includes high-pH positive-electrode active material is disposed outside the active substance layer that includes a lithium manganese-based positive-electrode active material, so as to make a layered electrode plate. In this way, the release of manganese metal from the lithium manganese-based active material of the positive-electrode plate is drastically reduced without affecting power performance of battery cell, thereby improving high-temperature performance of battery cell. This application also discloses a manufacturing method of the positive-electrode plate, a lithium-ion secondary battery that includes the positive-electrode plate, a battery module, a battery pack, and an apparatus.