Method for Preparing Positive Electrode Additive for Lithium Secondary Battery, and Positive Electrode Additive for Lithium Secondary Battery Prepared Thereby

Patent metadata

Field	Value
Publication number	US-2021265614-A1
Application number	US-201917252610-A
Country	US
Kind code	A1
Filing date	Oct 15, 2019
Priority date	Oct 18, 2018
Publication date	Aug 26, 2021
Grant date	—

Abstract

The present disclosure relates to a method for preparing a positive electrode additive for a lithium secondary battery having a high irreversible capacity and being capable of preventing gelation and reducing gas generation, and a positive electrode additive prepared thereby. The method for preparing the positive electrode additive includes the steps of: mixing a lithium raw material, a nickel raw material and, optionally, a raw material containing an element M, and then heat-treating the mixture, thereby preparing a predetermined lithium nickel oxide, wherein the lithium raw material includes Li2O and LiOH, and the LiOH is used in an amount of 5 to 10% by weight with respect to the total weight of the lithium raw material.

First claim

1 . A method for preparing a positive electrode additive for a lithium secondary battery, the method comprising the steps of:
mixing a lithium raw material, a nickel raw material and, optionally, a raw material containing an element M, and heat-treating the mixed raw materials to produce the lithium nickel oxide additive of Chemical Formula 1 below, wherein the lithium raw material includes Li 2 O and LiOH, the LiOH is present in an amount of 3 to 25% by weight with respect to the total weight of the lithium raw material
Li 2 Ni 1-x M x O 2   [Chemical Formula 1]

in Chemical Formula 1, M is selected from the group consisting of a transition metal, an amphoteric element, P, F, and B, provided that M is not nickel, and
0≤x<1.

2 . The method for preparing a positive electrode additive for a lithium secondary battery according to claim 1 , wherein the lithium raw material is composed of 70 to 95 mol % of Li 2 O, and 5 to 30 mol % of LiOH.

3 . The method for preparing a positive electrode additive for a lithium secondary battery according to claim 1 , wherein the nickel raw material includes NiO.

4 . The method for preparing a positive electrode additive for a lithium secondary battery according to claim 1 , wherein the M is selected from the group consisting of W, Ti, Zr, Al, P, F, and B.

5 . The method for preparing a positive electrode additive for a lithium secondary battery according to claim 1 , wherein the element M-containing raw material includes one or more selected from the group consisting of element M-containing: oxides, hydroxides, oxyhydroxides, sulfates, nitrates, acetates, carbonates, oxalates, citrates, halides, phosphates and their hydrates.

6 . The method for preparing a positive electrode additive for a lithium secondary battery according to claim 1 , wherein the heat treating step is carried out at a temperature of 500 to 900° C. for 5 to 25 hours.

7 . A positive electrode additive for a lithium secondary battery, comprising:
95 to 99.5% by weight of a lithium nickel oxide of Chemical Formula 1 below 0.5 to 5% by weight of NiO, and less than 5 parts by weight of LiOH and less than 0.6 parts by weight of Li 2 CO 3 based on 100 parts by weight of the total amount of the lithium nickel oxide and NiO.
Li 2 Ni 1-x M x O 2   [Chemical Formula 1]

in Chemical Formula 1, M is selected from the group consisting of a transition metal, an amphoteric element, P, F, and B, provided that M is not nickel, and
0≤x<1.

8 . A positive electrode mixture comprising the positive electrode additive of claim 7 ; and a positive electrode active material.

9 . The positive electrode mixture according to claim 8 , wherein a weight ratio of the positive electrode additive to the positive electrode active material is 1:99 to 35:65.

10 . The positive electrode mixture according to claim 8 , wherein the positive electrode activematerial is a composite oxides including lithium and one or more metals selected from the group consisting of cobalt, manganese, and nickel.

Assignees

• Lg Chemical Ltd

Inventors

• Lee Boram
• Park Sin Young
• Lee Daejin
• Kim Hakyoon
• Kim Taegon
• Jung Wang Mo

Classifications

• H01M4/364

  as mixtures · CPC title

• H01M4/131

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

• H01M4/525

  of mixed oxides or hydroxides containing iron, cobalt or nickel for inserting or intercalating light metals, e.g. LiNiO2, LiCoO2 or LiCoOxFy · CPC title

• H01M10/0525

  Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries · CPC title

• H01M4/1391

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