Positive electrode active material for lithium secondary batteries and lithium secondary batteries containing the same

Abstract

This embodiment relates to a positive electrode active material for a lithium secondary battery and a lithium secondary battery containing the same. A positive electrode active material for a lithium secondary battery according to one embodiment comprises a nickel-containing metal oxide in single-particle form; and a doping element doped into the nickel-containing metal oxide; wherein the doping element may include Al, Y, and Zr.

Claims

1. Nickel-containing metal oxides in single-particle form; and The nickel-containing metal oxide is doped with a doping element; The doping element is a positive electrode active material for lithium secondary batteries, comprising Al, Y, and Zr.

2. The positive electrode active material for a lithium secondary battery according to claim 1, wherein the cation mixing ratio of nickel cations in the lithium layer within the crystal structure of the doped nickel-containing metal oxide is 1.5% or less.

3. The positive electrode active material for a lithium secondary battery according to claim 1, wherein the Al content is in the range of 200 ppm to 1,800 ppm based on the nickel-containing metal oxide.

4. The positive electrode active material for a lithium secondary battery according to claim 1, wherein the content of Y is in the range of 400 ppm to 2,000 ppm based on the nickel-containing metal oxide.

5. The positive electrode active material for a lithium secondary battery according to claim 1, wherein the Zr content is in the range of 1,200 ppm to 2,800 ppm based on the nickel-containing metal oxide.

6. The nickel content is 0.8 moles or more, based on the total amount of transition metals contained in the nickel-containing metal oxide, as described in claim 1.

7. The nickel-containing metal oxide further contains cobalt, The positive electrode active material for a lithium secondary battery according to claim 1, wherein the cobalt content is 0.06 moles or less, based on 1 mole of the total transition metals contained in the doped nickel-containing metal oxide.

8. The nickel-containing metal oxide further contains manganese, The manganese content is 0.15 moles or less, based on the total amount of transition metals contained in the nickel-containing metal oxide, as described in claim 7.

9. The nickel-containing metal oxide is represented by the following chemical formula 1, and is the positive electrode active material for a lithium secondary battery according to claim 1: [Chemical formula 1] Li ａ [Ni ｘ Co ｙ Mn ｚ M1 ｗ１ M2 ｗ２ ]O ２ In the above chemical formula 1, 0.8 ≤ a ≤ 1.2, 0.8 ≤ x ≤ 0.99, 0 < y ≤ 0.06, 0 < z ≤ 0.14, 0 < w1 ≤ 0.05, 0 ≤ w2 ≤ 0.05, x + y + z + w1 + w2 = 1, M1 is Al, Y and Zr, and M2 contains one or more of B, Al, Mg, Ti, Nb, W, Sc, Si, V, Fe, Y, Mo, Ce, Hf, Ta, La and Sr.

10. The positive electrode active material for a lithium secondary battery according to claim 1, wherein the average particle size (D50) of the positive electrode active material is 3 μm or more.

11. The positive electrode active material for a lithium secondary battery according to claim 1, wherein when the positive electrode active material is subjected to five pressurizations using a roll press with a press gauge of 0.01 mm, the total value of fine particles less than 1 μm is 2 vol% or less.

12. The positive electrode active material for a lithium secondary battery according to claim 1, wherein the peak temperature obtained by differential scanning calorimetry (DSC) analysis is 230°C or higher.

13. A positive electrode for a lithium secondary battery comprising the positive electrode active material described in any one of claims 1 to 12.

14. A lithium secondary battery comprising a positive electrode for a lithium secondary battery as described in claim 13.

Images