Cathode active material for lithium rechargeable battery, method of manufacturing the same, and lithium rechargeable battery including the same

1. A cathode active material for a lithium rechargeable battery, comprising:

a core including a compound represented by the following Chemical Formula 1; and

a coating layer positioned on the core and including a compound represented by the following Chemical Formula 2:

x Li 2 MnO 3 — (1-x) LiM 1 O 2   [Chemical Formula 1]

wherein, in Chemical Formula 1, 0<x<1 and M 1 is a transition metal;

y MnO z — (1-y) LiM 2 O 2   [Chemical Formula 2]

wherein, in Chemical Formula 2, 0<y<1, 1≤z≤4, and M 2 is a transition metal,

wherein a thickness of the coating layer is 1 to 13 nm.

2. The cathode active material for a lithium rechargeable battery of claim 1 , further comprising

a reduced graphene oxide layer positioned on the coating layer.

3. The cathode active material for a lithium rechargeable battery of claim 2 , wherein

a thickness of the reduced graphene oxide layer is 1 to 5 nm.

4. The cathode active material for a lithium rechargeable battery of claim 1 , wherein

a Li/M molar ratio of the entire cathode active material including the core and the coating layer is 1.05 to 1.6.

5. The cathode active material for a lithium rechargeable battery of claim 1 , wherein

M 1 of Chemical Formula 1 and M 2 of Chemical Formula 2 include Ni, Co, or Mn.

6. A lithium rechargeable battery comprising:

a cathode including the cathode active material for the lithium rechargeable battery according to claim 1 ;

an anode including an anode active material; and

an electrolyte.