Lithium Secondary Battery Having Improved Lifespan Characteristics, Driving Method Therefor, Battery Module Comprising Same, and Battery Pack Comprising Battery Module

Patent metadata

Field	Value
Publication number	US-2023378454-A1
Application number	US-202218027713-A
Country	US
Kind code	A1
Filing date	Mar 31, 2022
Priority date	Jun 30, 2021
Publication date	Nov 23, 2023
Grant date	—

Abstract

A lithium secondary battery with improved lifetime characteristics, a driving method thereof, a battery module including the same, and a battery pack including the battery module, provides the lithium secondary battery having an operating voltage that is less than a plateau voltage of the lithium/nickel composite oxide, and thus has an advantage of being enable to prevent the lithium/nickel composite oxide from being transferred to a spinel-like structure, suppress the capacity degradation according to an increase in cycle, and improve a lifetime characteristic.

First claim

1 . A lithium secondary battery comprising:
a positive electrode; a negative electrode; and a separator disposed between the positive electrode and the negative electrode, wherein the positive electrode includes a lithium/nickel composite oxide represented by Chemical Formula 1 as a positive electrode active material, and the lithium/nickel composite oxide has a plateau voltage ranging from 4.1 V to 4.5 V of a charge/discharge profile, wherein the lithium secondary battery is configured to have an operating voltage that is less than the plateau voltage:
Li x [Ni y Co z Mn w M 1 v ]O u   Chemical Formula 1

wherein M 1 is at least one doping element selected from the group consisting of W, Cu, Fe, V, Cr, Zr, Zn, Al, In, Ta, Y, La, Sr, Ga, Sc, Gd, Sm, Ca, Ce, Nb, Mg, B, and Mo, and wherein x, y, z, w, v, and u are 1.0≤x≤1.30, 0.6≤y≤0.95, 0.01≤z≤0.5, 0.01≤w≤0.5, 0≤v≤0.2, and 1.5≤u≤4.5.

2 . The lithium secondary battery of claim 1 , wherein:
the lithium/nickel composite oxide has the plateau voltage at an average of 4.2V of the charge/discharge profile; and the lithium secondary battery has the operating voltage that is greater than or equal to 3.0 V and less than 4.2 V.

3 . The lithium secondary battery of claim 1 , wherein the positive electrode active material includes one or more of Li(Ni 0.6 Co 0.2 Mn 0.2 )O 2 , Li(Ni 0.7 Co 0.15 Mn 0.15 )O 2 , Li(Ni 0.8 Co 0.1 Mn 0.1 )O 2 , Li(Ni 0.9 Co 0.05 Mn 0.05 )O 2 , Li(Ni 0.6 Co 0.2 Mn 0.1 Zr 0.1 )O 2 , Li(Ni 0.6 Co 0.2 Mn 0.15 Zr 0.05 )O 2 , or Li(Ni 0.7 Co 0.1 Mn 0.1 Zr 0.1 )O 2 .

4 . The lithium secondary battery of claim 1 , wherein the M 1 includes Zr.

5 . The lithium secondary battery of claim 4 , wherein the lithium/nickel composite oxide includes the M 1 in an amount of 300 ppm to 7,000 ppm.

6 . The lithium secondary battery of claim 1 , wherein the positive electrode active material has a layered structure.

7 . The lithium secondary battery of claim 1 , wherein, when the lithium secondary battery is charged and discharged with 3800 cycles at a temperature of 25° C., a capacity retention is 90% or more.

8 . The lithium secondary battery of claim 1 , wherein, when the lithium secondary battery is charged and discharged with 3400 cycles at a temperature of 45° C., a capacity retention is 85% or more.

9 . The lithium secondary battery of claim 1 , wherein, when the lithium secondary battery is charged and discharged with 3800 cycles at a temperature of 25° C., a direct current internal resistance (DCIR) increment is 10% or less.

10 . A driving method of a lithium secondary battery including a positive electrode, a negative electrode, and a separator disposed between the positive electrode and the negative electrode, the driving method comprising:
controlling an operating voltage of the lithium secondary battery to be less than a plateau voltage of a lithium/nickel composite oxide, wherein the positive electrode includes the lithium/nickel composite oxide represented by Chemical Formula 1 as a positive electrode active material, and the lithium/nickel composite oxide has the plateau voltage ranging from 4.1 V to 4.5 V of a charge/discharge profile:
Li x [Ni y Co z Mn w M 1 v ]O u   Chemical Formula 1

wherein M 1 is at least one doping element selected from the group consisting of W, Cu, Fe, V, Cr, Zr, Zn, Al, In, Ta, Y, La, Sr, Ga, Sc, Gd, Sm, Ca, Ce, Nb, Mg, B, and Mo, and wherein x, y, z, w, v, and u are 1.0≤x≤1.30, 0.6≤y≤0.95, 0.01≤z≤0.5, 0.01≤w≤0.5, 0≤v≤0.2, and 1.5≤u≤4.5.

11 . The driving method of claim 10 , wherein:
the lithium/nickel composite oxide has the plateau voltage at an average of 4.2V of the charge/discharge profile; and the operating voltage is greater than or equal to 3.0 V and less than 4.2 V.

12 . A battery module comprising the lithium secondary battery according to claim 1 , and an electrolyte.

13 . A battery pack comprising the battery module according to claim 12 , the battery pack including a plurality of the battery modules.

14 . An electric vehicle comprising the battery pack of claim 13 and at least two wheels.

Assignees

• Lg Energy Solution Ltd

Inventors

• Bae Sung Hoon
• Lee Young Hwan
• Chung Mi Kyung
• Park Su Han

Classifications

• C01P2002/20

  Two-dimensional structures · CPC title

• C01P2002/52

  containing elements as dopants · CPC title

• C01P2002/54

  one element only · CPC title

• C01P2006/40

  Electric properties · CPC title

• C01G53/506

  with the molar ratio of nickel with respect to all the metals other than alkali metals higher than or equal to 0.8, e.g. Li(MzNixCoyMn1-x-y-z)O2 with x ≥ 0.8 · CPC title