Positive Electrode Active Material Precursor for Secondary Battery, Preparation Method Thereof, and Method of Preparing Positive Electrode Active Material

Patent metadata

Field	Value
Publication number	US-2022238871-A1
Application number	US-202017606648-A
Country	US
Kind code	A1
Filing date	Sep 25, 2020
Priority date	Sep 26, 2019
Publication date	Jul 28, 2022
Grant date	—

Abstract

A method of preparing a positive electrode active material precursor for a secondary battery includes preparing a positive electrode active material precursor by a co-precipitation reaction while adding a transition metal-containing solution containing transition metal cations, a basic solution, and an ammonium solution to a batch-type reactor, wherein a molar ratio of ammonium ions contained in the ammonium solution to the transition metal cations contained in the transition metal-containing solution added to the batch-type reactor is 0.5 or less, and a pH in the batch-type reactor is maintained at 11.2 or less.

First claim

1 . A method of preparing a positive electrode active material precursor for a secondary battery, the method comprising: preparing a positive electrode active material precursor by a co-precipitation reaction while adding a transition metal-containing solution containing transition metal cations, a basic solution, and an ammonium solution to a batch-type reactor,
wherein a molar ratio of ammonium ions contained in the ammonium solution to the transition metal cations contained in the transition metal-containing solution added to the batch-type reactor is 0.5 or less, and a pH in the batch-type reactor is maintained at 11.2 or less.

2 . The method of claim 1 , wherein the molar ratio of the ammonium ions contained in the ammonium solution to the transition metal cations contained in the transition metal-containing solution added to the batch-type reactor is in a range of 0.1 to 0.5.

3 . The method of claim 1 , wherein the pH in the batch-type reactor is maintained at 10.8 to 11.2.

4 . The method of claim 1 , wherein particle nucleation and particle growth are performed without changing the pH in the batch-type reactor during the co-precipitation reaction.

5 . The method of claim 1 , wherein, during the co-precipitation reaction, a stirring speed in a particle nucleation step is in a range of 600 rpm to 800 rpm, and a stirring speed in a particle growth step is in a range of 200 rpm to 400 rpm.

6 . The method of claim 1 , wherein the positive electrode active material precursor has an aspect ratio of a primary particle of less than 0.5.

7 . The method of claim 1 , wherein the positive electrode active material precursor has an average particle diameter (D 50 ) of a secondary particle of 4 μm to 20 μm and has a specific surface area of 9 m 2 /g or more.

8 . The method of claim 7 , wherein the specific surface area is from 9 m 2 /g to 13 m 2 /g.

9 . The method of claim 1 , wherein the positive electrode active material precursor is represented by Formula 1:
[Ni x Co y Mn z M 1 w ](OH) 2   [Formula 1]
wherein, in Formula 1, M 1 comprises at least one element selected from the group consisting of zirconium (Zr), boron (B), tungsten (W), molybdenum (Mo), chromium (Cr), niobium (Nb), aluminum (Al), magnesium (Mg), hafnium (Hf), tantalum (Ta), lanthanum (La), titanium (Ti), strontium (Sr), barium (Ba), cerium (Ce), fluorine (F), phosphorus (P), sulfur (S), and yttrium (Y), 0.8≤x<1, 0<y≤0.1, 0<z≤0.1, 0≤w≤0.1, and x+y+z+w=1.

10 . A method of preparing a positive electrode active material for a secondary battery, comprising:
mixing the positive electrode active material precursor for a secondary battery, which is prepared according to claim 1 , with a lithium source and sintering the mixture to form a lithium transition metal oxide.

11 . A positive electrode active material precursor for a secondary battery which is prepared according to claim 1 , wherein an aspect ratio of a primary particle is less than 0.5,
an average particle diameter (D 50 ) of a secondary particle is in a range of 4 μm to 20 μm, and a specific surface area is 9 m 2 /g or more.

12 . A positive electrode active material for a secondary battery which is prepared according to claim 10 , wherein a pellet density is 2.80 g/cc or more.

Assignees

• Lg Chemical Ltd

Inventors

• Lee Min Joon
• Cho Seung Beom
• Ye Seong Ji
• Park Yoon Bin

Classifications

• Y02E60/10

  Energy storage using batteries · CPC title

• C01P2006/40

  Electric properties · CPC title

• C01P2006/12

  Surface area · CPC title

• C01P2006/11

  Powder tap density · CPC title

• C01P2006/10

  Solid density · CPC title