Cathode additive, preparation method thereof, and cathode and lithium secondary battery comprising the same

Patent metadata

Field	Value
Publication number	US-11404693-B2
Application number	US-201816756950-A
Country	US
Kind code	B2
Filing date	Nov 27, 2018
Priority date	Nov 27, 2017
Publication date	Aug 2, 2022
Grant date	Aug 2, 2022

Abstract

The present disclosure relates to a cathode additive, a method for preparing the same, and a cathode and a lithium secondary battery including the same. More specifically, one embodiment of the present disclosure provides a cathode additive that can offset an irreversible capacity imbalance, and increase the initial charge capacity of a cathode.

First claim

The invention claimed is:

1. A cathode mixture comprising:
a cathode active material including one or more composite oxides of: a metal of cobalt, manganese, nickel, and lithium, wherein the composite oxide includes cobalt, manganese, nickel, and lithium in a composite oxide; and
a cathode additive composition represented by the following Chemical Formula 1:
{ x (Li 2+a Ni b M 1-b O 2+c )}.{ y (NiO)}.{ z (Li 2 O)}  [Chemical Formula 1]

wherein, in Chemical Formula 1,
M is one or more metal atoms forming a divalent cation or a trivalent cation,
−0.2≤a≤0.2, 0.5≤b≤1.0, −0.2≤c≤0.2,
0.7≤x≤0.93, 0<y≤0.15, 0.07≤z≤0.15, and x+y+z=1.

2. The cathode mixture according to claim 1 , wherein y=z.

3. The cathode mixture according to claim 1 , wherein, for the cathode additive, a peak by lithium oxide (Li 2 O) is detected in at least one of a range which 2θ is 30 to 35°, a range in which 2θ is 35 to 40°, or a range in which 2θ is 55 to 60°, by XRD (X-Ray Diffraction) measurement by Fe Kα X-ray (X-rα).

4. The cathode mixture according to claim 1 , wherein the content of lithium oxide (Li 2 O) in the total amount of the cathode additive (100 wt %) is greater than 7 wt % to 15 wt %.

5. The cathode mixture according to claim 1 , wherein for the cathode additive, a peak by nickel oxide (NiO) is detected in at least one of a range in which 2θ is 35 to 40°, a range in which 2θ is 40 to 45°, or a range in which 2θ is 50 to 55°, by XRD (X-Ray Diffraction) measurement by Fe Kα X-ray (X-rα).

6. The cathode mixture according to claim 1 , wherein the content of nickel oxide (NiO) in the total amount of the cathode additive (100 wt %) is greater than 0 wt % and equal to or less than 15 wt %.

7. The cathode mixture according to claim 1 , wherein the cathode additive is included in the content of 1 to 30 wt %, based on the total weight of the mixture (100 wt %).

8. The cathode mixture according to claim 1 , further comprising a conductive material, a binder, or a mixture thereof.

9. The cathode mixture according to claim 1 , wherein 0.7≤x≤0.86, 0.07≤y≤0.15, 0.07≤z≤0.15, and x+y+z=1.

10. A lithium secondary battery comprising:
a cathode comprising the cathode mixture of claim 1 ;
an electrolyte; and
an anode.

11. The lithium secondary battery according to claim 10 , wherein the anode includes one or more anode active materials selected from the group consisting of a carbon-based anode active material, a lithium metal, a lithium alloy, Si, SiO x (0<x<2), a Si—C composite, a Si-Q alloy (wherein Q is an alkali metal, an alkali earth metal, atoms of Groups 13 to 16, a transition metal, a rare earth atom, or a combination thereof, provided that it is not Si), Sn, SnO 2 , a Sn—C composite, and a Sn-R (R is an alkali metal, an alkali earth metal, atoms of Groups 13 to 16, a transition metal, a rare earth metal, or a combination thereof, provided that it is not Sn).

Assignees

• Lg Chemical Ltd
• Lg Energy Solution Ltd

Inventors

• Kim Ji Hye
• Park Byungchun
• Han Jungmin
• Jung Wang Mo

Classifications

• C01G53/42

  containing alkali metals, e.g. LiNiO2 · CPC title

• H01M4/131 Primary

  Electrodes based on mixed oxides or hydroxides, or on mixtures of oxides or hydroxides, e.g. LiCoOx · CPC title

• C01D15/02

  Oxides; Hydroxides · CPC title

• C01P2006/40

  Electric properties · CPC title

• H01M2004/028

  Positive electrodes · CPC title