Method for preparing positive electrode active material precursor for lithium secondary battery

Patent metadata

Field	Value
Publication number	US-11183685-B2
Application number	US-201816476983-A
Country	US
Kind code	B2
Filing date	May 24, 2018
Priority date	Jun 29, 2017
Publication date	Nov 23, 2021
Grant date	Nov 23, 2021

Abstract

The present invention provides a method of preparing a positive electrode active material precursor for a lithium secondary battery, a method of preparing a positive electrode active material for a lithium secondary battery in which the positive electrode active material precursor prepared by using the above method is used, and a positive electrode for a lithium secondary battery and a lithium secondary battery which include the positive electrode active material.

First claim

The invention claimed is:

1. A method of preparing a positive electrode active material precursor for a lithium secondary battery comprising:
adding a reaction solution including a first transition metal-containing solution, a second transition metal-containing solution, an ammonium ion-containing solution, and a basic aqueous solution to a batch reactor, wherein the adding of the reaction solution is done while continuously discharging a portion of the reaction solution in the batch reactor to outside of the batch reactor when the batch reactor is full, and
forming positive electrode active material precursor particles,
wherein the first transition metal-containing solution comprises 50 mol % to 98 mol % of nickel, 1 mol % to 40 mol % of manganese, and 1 mol % to 40 mol % of cobalt,
wherein the second transition metal-containing solution comprises 20 mol % to 80 mol % of nickel, 1 mol % to 60 mol % of manganese, and 1 mol % to 60 mol % of cobalt,
wherein an initial input flow rate of the reaction solution added to the batch reactor satisfies following Equation 1,
a pH in the batch reactor satisfies following Equation 2, and
an input flow rate of the basic aqueous solution satisfies following Equation 3:
1.5× V/t≤υ i +υ 2 +υ 3 ≤10× V/t   [Equation 1]

wherein, in Equation 1, V is a volume of the batch reactor, t is total reaction time (minutes), v i is a total initial input flow rate (mL/min) of the first transition metal-containing solution and the second transition metal-containing solution, v 2 is an initial input flow rate (mL/min) of the ammonium ion-containing solution, and v 3 is an initial input flow rate (mL/min) of the basic aqueous solution, and
pH 0 −{([Ni] 0 −[Ni] ti )×0.05}≤pH t1 ≤pH 0 −{([Ni] 0 −[Ni] t1 )×0.005}  [Equation 2]

wherein, in Equation 2,
pH t1 is a pH in the batch reactor at time t1, pH 0 is an initial pH in the batch reactor, [Ni] 0 is a molar concentration of nickel (Ni) in the transition metal-containing solution initially added, and [Ni] t1 is a molar concentration of Ni in the transition metal-containing solution added at time t1,
υ 3,0 ×{1−(0.02×([Ni] 0 −[Ni] t2 ))}≤υ 3,t2 <υ 3,0   [Equation 3]

wherein, in Formula υ 3,t2 is an input flow rate of the basic aqueous solution at time t2, υ 3,0 is an initial input flow rate of the basic aqueous solution, [Ni] 0 is a molar concentration of Ni in the transition metal-containing solution initially added, and [Ni] t2 is a molar concentration of Ni in the transition metal-containing solution added at time t2,
wherein formation of a nucleus of positive electrode active material precursor particles occurs when the pH is in a range of 11.5 to 12, and growth of the positive electrode active material precursor particles occurs when the pH is in a range of 10.5 to 11.5.

2. The method of claim 1 , wherein concentrations of the cation included in the first transition metal-containing solution and the second transition metal-containing solution are different.

3. The method of claim 1 , wherein the first transition metal-containing solution and the second transition metal-containing solution are added to the batch reactor after being mixed using a static mixer.

4. The method of claim 1 , wherein the ammonium ion-containing solution comprises NH 4 OH, (NH 4 ) 2 SO 4 , NH 4 NO 3 , NH 4 Cl, CH 3 COONH 4 , or NH 4 CO 3 .

5. The method of claim 1 , wherein the basic aqueous solution comprises NaOH, KOH, or Ca(OH) 2 .

6. The method of claim 1 , wherein the pH in the batch reactor is controlled by an input flow rate of the basic aqueous solution.

7. The method of claim 1 , wherein the discharge of the reaction solution is performed by using a tube including a filter.

8. A method of preparing a positive electrode active material for a lithium secondary battery, comprising:
mixing a lithium-containing raw material with a positive electrode active material precursor prepared by the method of claim 1 to form a mixed resultant, and
sintering the mixed resultant.

9. A positive electrode for a lithium secondary battery, comprising:
a positive electrode active material prepared by the method of claim 8 .

10. A lithium secondary battery comprising the positive electrode of claim 9 .

11. The method of claim 1 , wherein the positive electrode active material precursor particles have a (D 90 −D 10 )/D 50 of 0.6 to 0.9.

Assignees

• Lg Chemical Ltd

Inventors

• Jung Won Sig
• Choi Sang Soon
• Park Hyun Ah

Classifications

• C01G53/82 Primary

  Compounds containing nickel, with or without oxygen or hydrogen, and containing two or more other elements · CPC title

• C01G53/44 Primary

  containing manganese · CPC title

• Y02E60/10

  Energy storage using batteries · CPC title

• H01M4/505

  of mixed oxides or hydroxides containing manganese for inserting or intercalating light metals, e.g. LiMn2O4 or LiMn2OxFy · CPC title

• C01G53/04

  Oxides · CPC title