Method For Preparing Positive Electrode Additives Of Lithium Secondary Battery

Patent metadata

Field	Value
Publication number	US-2020176754-A1
Application number	US-201816615519-A
Country	US
Kind code	A1
Filing date	Nov 21, 2018
Priority date	Nov 22, 2017
Publication date	Jun 4, 2020
Grant date	—

Abstract

The present disclosure provides a preparing method of a positive electrode additive for a lithium secondary battery capable of reducing the amount of Li-based byproduct and unreacted lithium oxide generated in a preparing process, thereby significantly reducing the amount of gas generated when the electrode is operated.

First claim

1 . A method for preparing a positive electrode additive of a lithium secondary battery, comprising
mixing a lithium raw material, a nickel raw material, and a raw material of an element M, and heat treating them under an atmosphere of an inert gas to produce a lithium nickel oxide of Chemical Formula 1 below, wherein the heat treating comprises first heat treating at 300° C. to 500° C., and second heat treating at 550° C. to 800° C. after the first heat treating, and the first heat treating is performed for 30% to 50% of a total duration of the heat treating, wherein the positive electrode additive comprises the lithium nickel oxide of Chemical Formula 1:
Li 2 Ni 1-x M x O 2   [Chemical Formula 1]

wherein, in Chemical Formula 1, M is a transition metal, an amphoteric element, P, F, or B, wherein M is not nickel, and 0<x<1.

2 . The method of claim 1 , wherein the first heat treating is performed for 35% to 45% of the total duration of the heat treating at 330° C. to 450° C.

3 . The method of claim 1 , wherein the first heat treating comprises a temperature rising step of heating to a temperature of 300° C. to 500° C. at a rate of 2° C./min to 7° C./min, and a maintaining step of maintaining the heated temperature for 40% to 80% of the total duration of the first heat treating.

4 . The method of claim 1 , wherein the second heat treating is performed at 600° C. to 800° C.

5 . The method of claim 1 , wherein the second heat treating comprises a temperature rising step of heating to a temperature of 550° C. to 800° C. at a rate of 2° C./min to 7° C./min and a maintaining step of maintaining the heated temperature for 60% to 90% of the total duration of the second heat treating.

6 . The method of claim 1 , wherein the lithium raw material is used in an amount such that a mole ratio of lithium:(nickel+element M) is 2:1 when mixing the lithium raw material, the nickel raw material, and the raw material of the element M.

7 . The method of claim 1 , wherein the lithium raw material comprises any one or a mixture of two or more selected from the group consisting of a lithium-containing oxide, a hydroxide, an oxyhydroxide, a sulfate, a nitrate, an acetate, a carbonate, an oxalate, a citrate, a halide, and hydrates thereof.

8 . The method of claim 1 , wherein the raw material of the element M comprises any one or a mixture of two or more selected from the group consisting of an oxide, a hydroxide, an oxyhydroxide, a sulfate, a nitrate, an acetate, a carbonate, an oxalate, a citrate, a halide, a phosphate, and hydrates thereof that contain the element M.

9 . The method of claim 1 , wherein the Ni raw material comprises NiO.

10 . The method of claim 1 , wherein the element M is selected from the group consisting of W, Ti, Zr, Al, P, F, and B.

11 . The method of claim 1 , wherein the positive electrode additive further comprises less than 11 wt % NiO and 1 wt % or less Li 2 O based on a total weight of the positive electrode additive, wherein a total amount of the NiO and the Li 2 O is less than or equal to 11 wt % based on a total weight of the positive electrode additive.

12 . A positive electrode additive for a lithium secondary battery, comprising a lithium nickel oxide of Chemical Formula 1, wherein the positive electrode additive further comprises less than 11 wt % NiO and 1 wt % or less Li 2 O based on the total weight of the positive electrode additive, wherein a total amount of the NiO and the Li 2 O is less than or equal to 11 wt % based on a total weight of the positive electrode additive:
Li 2 Ni 1-x M x O 2   [Chemical Formula 1]
wherein, in Chemical Formula 1, M is a transition metal, an amphoteric element, P, F, or B, wherein M is not nickel, and 0<x<1.

13 . The positive electrode additive of claim 12 , wherein after being charged at 0.1 C to 3.8 V at 25° C. and then being analyzed using X-ray diffraction, the positive electrode additive has a peak intensity ratio of d1/d2=0, when a peak intensity appearing at 2θ=30° to 35° is d1 and a peak intensity appearing at 2θ=15° to 20° is d2.

14 . A positive electrode for a lithium secondary battery comprising the positive electrode additive of claim 12 .

15 . A lithium secondary battery comprising: a positive electrode comprising the positive electrode additive of claim 12 ; an electrolyte; and a negative electrode.

Assignees

• Lg Chemical Ltd

Inventors

• Lho Eunsol
• Jeon Hyelim
• Lee Donghun
• Lee Sang Wook
• Jung Wang Mo
• Kang Minsuk
• Baek Sora

Classifications

• H01M2004/028

  Positive electrodes · CPC title

• H01M4/0471

  involving thermal treatment, e.g. firing, sintering, backing particulate active material, thermal decomposition, pyrolysis · 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 Primary

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

• H01M4/485

  of mixed oxides or hydroxides for inserting or intercalating light metals, e.g. LiTi2O4 or LiTi2OxFy (H01M4/505, H01M4/525 take precedence) · CPC title