Cathode active material precursor, cathode active material, lithium secondary battery and method of manufacturing the same
A cathode active material precursor according to embodiments of the present invention includes a composite hydroxide particle in which primary precursor particles are aggregated. The primary precursor particles include a particle having a triangular shape in which a minimum interior angle is 30° or more and a ratio of a length of a short side relative to a length of a long side is 0.5 or more. A cathode active material and a lithium secondary having improved high temperature stability is provided using the cathode active material precursor.
1. A cathode active material precursor comprising a composite hydroxide particle in which primary precursor particles are aggregated, the composite hydroxide particle containing nickel, and a molar ratio of nickel in metals included in the composite hydroxide particle is in a range from 0.8 to 0.95,
wherein the primary precursor particles include a particle having a triangular shape in which a minimum interior angle is 30° or more and a ratio of a length of a short side relative to a length of a long side is 0.5 or more, and
wherein the composite hydroxide particle has a specific surface area of 0.89 m 2 /g or less.
2. The cathode active material precursor of claim 1 , wherein the composite hydroxide particle further includes cobalt.
3. The cathode active material precursor of claim 2 , wherein the composite hydroxide particle further includes manganese.
4. The cathode active material precursor of claim 1 , wherein the composite hydroxide particle is represented by Chemical Formula 1:
Ni α Co β M γ (OH) z [Chemical Formula 1]
wherein in Chemical Formula 1, M includes at least one selected from the group consisting of Mg, Sr, Ba, B, Al, Si, Mn, Ti, Zr and W, 0.8≤α≤0.95, 0≤γ/(α+β)≤0.13, 0≤γ≤0.11 and 1.9≤z≤2.1.
5. The cathode active material precursor of claim 1 , wherein the ratio of the length of the short side relative to the length of the long side is 0.8 or more.
6. A cathode active material for a secondary battery, comprising a lithium composite oxide particle formed from the cathode active material precursor of claim 1 .
7. The cathode active material for a secondary battery of claim 6 , wherein the lithium composite oxide particle has an amorphous shape.
8. A lithium secondary battery, comprising:
a cathode comprising the cathode active material of claim 6 ; and
an anode facing the cathode.