Lithium ion battery positive plate, preparation method thereof and lithium ion battery

The invention relates to a lithium ion battery positive plate, a preparation method thereof and a lithium ion battery. The lithium ion battery positive plate comprises at least three stacked electrode layers; a positive active material in the electrode layer comprises at least two of lithium manganese iron phosphate, lithium manganate or nickel cobalt lithium manganate; the chemical formula of the lithium manganese iron phosphate is LiMnxFe1-xPO4, and x is more than or equal to 0.6 and less than or equal to 0.8; and the chemical formula of the nickel cobalt lithium manganate is Li (NiaCobMnc) O2, a is more than or equal to 0.65 and less than or equal to 0.8, b is more than 0 and less than or equal to 0.1, c is more than 0 and less than or equal to 0.5, and a + b + c = 1. According to the lithium ion battery, at least three electrode layers and the gradient-distributed positive electrode active material are laminated, and the particle size range of lithium manganese iron phosphate in the positive electrode act