Lithium-cobalt based complex oxide having superior lifespan characteristics and cathode active material for secondary batteries including the same
View Patent ↗Disclosed is a lithium-cobalt based complex oxide represented by Formula 1 below including lithium, cobalt and manganese wherein the lithium-cobalt based complex oxide maintains a crystal structure of a single O3 phase at a state of charge (SOC) of 50% or more based on a theoretical amount: Li x Co 1-y-z Mn y A z O 2 (1) wherein 0.95≤x≤1.15, 0≤y≤0.3 and 0≤z≤0.2; and A is at least one element selected the group consisting of Al, Mg, Ti, Zr, Sr, W, Nb, Mo, Ga, and Ni.
1. A lithium-cobalt based complex oxide represented by Formula 1 below comprising lithium, cobalt and manganese, wherein the lithium-cobalt based complex oxide maintains a crystal structure of a single O3 phase at a state of charge (SOC) of 50% or more based on theoretical capacity:
Li x Co 1-y-z Mn y A z O 2 (1)
wherein 0.95≤x≤1.15, 0<y<0.045 and 0<z≤0.0003; and
A is at least one element selected the group consisting of Al, Mg, Ti, and Ni, wherein at least one element of A is Mg.
2. The lithium-cobalt based complex oxide according to claim 1 , wherein the lithium-cobalt based complex oxide maintains the crystal structure of the single O3 phase when delithiation progresses in 50% or more of the lithium-cobalt based complex oxide.
3. The lithium-cobalt based complex oxide according to claim 1 , wherein the lithium-cobalt based complex oxide maintains the crystal structure of the single O3 phase under operating voltage of 4.35 V or more.
4. The lithium-cobalt based complex oxide according to claim 3 , wherein the lithium-cobalt based complex oxide maintains the crystal structure of the single O3 phase under operating voltage of 4.35 V or more to 4.5 V or less.
5. The lithium-cobalt based complex oxide according to claim 1 , wherein an average particle size of the lithium-cobalt based complex oxide is 0.5 micrometers to 30 micrometers.
6. A cathode active material comprising the lithium-cobalt based complex oxide according to claim 1 .
7. A cathode mixture for secondary batteries comprising the cathode active material according to claim 6 .
8. A cathode for secondary batteries comprising the cathode mixture for secondary batteries according to claim 7 coated on a collector.
9. A lithium secondary battery comprising the cathode for secondary batteries according to claim 8 .
10. A battery module comprising the lithium secondary battery according to claim 9 as a unit battery.
11. A device comprising the lithium secondary battery according to claim 9 .
12. A device comprising the battery module according to claim 10 .
13. The device according to claim 11 , wherein the device is a mobile phone, a tablet PC, a laptop computer, an electric vehicle, a hybrid electric vehicle, a plug-in hybrid electric vehicle, or a system for storing power.
14. The device according to claim 12 , wherein the device is a mobile phone, a tablet PC, a laptop computer, an electric vehicle, a hybrid electric vehicle, a plug-in hybrid electric vehicle, or a system for storing power.