Positive electrode and lithium-ion battery

A lithium-ion battery, comprising a positive electrode, wherein the positive electrode comprising:

• a current collector;
• a first active material layer with a first active material;
• and
• a second active material layer;
• wherein the first active material layer is coated on at least one surface of the current collector and the second active material layer is coated on the first active material layer so that the first active material layer is arranged between the current collector and the second active material layer, and the first active material consists of compounds represented by Chemical Formula 2:
• LiyM2eFe1-ePO4-f Chemical Formula 2,
• wherein M2 represents bismuth, and the values of y, e and f are respectively in the following ranges:
• 0.9≤y≤1.1, 0<e≤0.01, −0.1≤f≤0.1,
• wherein a differential scanning calorimetry (DSC) of a two-layered structure of the first active material layer and the second active material layer has a temperature corresponding to an exothermic peak beyond 301° C.;
• wherein the second active material layer comprises a second active material, and the second active material is selected from the group consisting of lithium cobalt oxide, transition metal element doped lithium cobalt oxide, metal oxide coated lithium cobalt oxide, and combinations thereof;
• and
• wherein the content of M2 is in a range of 10 ppm to 3000 ppm, based on a total weight of the compound represented by the chemical formula 2.