| 摘要 |
PURPOSE: A positive active material is provided to provide a lithium secondary battery with excellent thermal stability, excellent cycle lifetime at high temperature, and a quick charging and discharging rate. CONSTITUTION: A positive active material comprises a lithium metal oxide and a phosphoric acid silicon compound which is located on the surface of a lithium metal oxide, and indicated in chemical formula 1: Si_xP_yO_z. In chemical formula 1, 1<=x<=5, 1<=y<=6, and 7<=z<=25. The lithium metal oxide comprises a nickel-based oxide. The comprised amount of the phosphoric acid silicon compound is 0.3-1 weight% based on a positive electrode active material. The positive electrode active material includes a silicon oxide, phosphoric lithium compound, or solid solution thereof. |
