Lithium Secondary Battery

Patent metadata

Field	Value
Publication number	US-2025192220-A1
Application number	US-202519057450-A
Country	US
Kind code	A1
Filing date	Feb 19, 2025
Priority date	Jul 21, 2021
Publication date	Jun 12, 2025
Grant date	—

Abstract

A lithium secondary battery includes a positive electrode, a negative electrode, a separator, and an electrolyte, wherein the positive electrode includes a positive electrode active material layer having a positive electrode active material containing an overlithiated manganese-based oxide represented by Formula 1 below, and the negative electrode includes a negative electrode active material layer having a silicon-based negative electrode active materialLiaNibCocMndMeO2  [Formula 1]wherein, M is at least one selected from the group consisting of Al, B, Co, W, Mg, V, Ti, Zn, Ga, In, Ru, Nb, Sn, Sr, and Zr, and 1≤a, 0≤b≤0.5, 0≤c≤0.1, 0.5≤d<1.0, and 0≤e≤0.2, and. Preferably, in the Formula 1, 1.1≤a≤1.5, 0.1≤b≤0.4, 0≤c≤0.05, 0.5≤d≤0.80, and 0≤e≤0.1.

First claim

1 . A lithium secondary battery, comprising:
a positive electrode; and a negative electrode, wherein the positive electrode comprises a positive electrode active material layer comprising a positive electrode active material comprising an overlithiated manganese-based oxide represented by following Formula 1:
Li a Ni b Co c Mn a MeO 2   (1),

wherein
M is at least one element selected from the group consisting of Al, B, Co, W, Mg, V, Ti, Zn, Ga, In, Ru, Nb, Sn, Sr, and Zr, 1<a, 0≤b≤0.5, 0≤c≤0.08, 0.5≤d<1.0, and 0≤e≤0.2, and the negative electrode comprises a negative electrode active material layer comprising a silicon-based negative electrode active material:

2 . The lithium secondary battery of claim 1 , wherein in the Formula 1, 1.1≤a≤1.5, 0.1≤b≤0.4, 0≤c≤0.05, 0.5≤d≤0.80, and 0≤e≤0.1.

3 . The lithium secondary battery of claim 1 , wherein the overlithiated manganese-based oxide is represented by following Formula 2:
X Li 2 MnO 3 ·(1−X) Li[Ni 1-y-z-w Mn y CO 2 M w ]O 2   (2),

wherein
M is at least one selected from the group consisting of Al, B, Co, W, Mg, V, Ti, Zn, Ga, In, Ru, Nb, Sn, Sr, and Zr, and 0.2≤X≤0.5, 0.4≤y≤1, 0≤z≤0.08, and 0≤w≤0.2.

4 . The lithium secondary battery of claim 1 , wherein the positive electrode active material has an average particle diameter D50 of from 2 mm to 10 mm.

5 . The lithium secondary battery of claim 1 , wherein the positive electrode active material has a BET specific surface area of from 1 m 2 /g to 10 m 2 /g.

6 . The lithium secondary battery of claim 1 , wherein
the positive electrode has an initial irreversible capacity of from 5% to 70%.

7 . The lithium secondary battery of claim 1 , wherein the silicon-based negative electrode active material has an initial efficiency of from 60% to 95%.

8 . The lithium secondary battery of claim 1 , wherein the negative electrode active material layer further comprises a conductive material and a binder,
wherein the conductive material comprises a single-walled carbon nanotube.

9 . The lithium secondary battery of claim 1 , wherein the silicon-based negative electrode active material has an average particle diameter D50 of from 3 mm to 8 mm.

10 . The lithium secondary battery of claim 1 , wherein the negative electrode active material layer has a porosity of from 20% to 70%.

11 . The lithium secondary battery of claim 1 , wherein the negative electrode active material is a mixture of the silicon-based negative electrode active material and a carbon-based negative electrode active material.

12 . The lithium secondary battery of claim 11 , wherein the silicon-based negative electrode active material is included in an amount of from 1 wt. % to 30 wt. % and the carbon-based negative electrode active material is included in an amount of from 70 wt. % to 99 wt. %, with respect to a total weight of the negative electrode active material.

13 . The lithium secondary battery of claim 11 , wherein the silicon-based negative electrode active material comprises silicon oxide, and
wherein the lithium secondary battery has an N/P ratio of from 100% to 150%.

13 . The lithium secondary battery of claim 11 , wherein the negative electrode has a multi-layer structure comprising two or more negative electrode active material layers.

14 . The lithium secondary battery of claim 11 , wherein the negative electrode comprises a negative electrode collector, a first negative electrode active material layer disposed on the negative electrode collector, and a second negative electrode active material layer disposed on the first negative electrode active material layer, and
wherein the second negative electrode active material layer has a higher content of conductive material than the first negative electrode active material layer.

15 . The lithium secondary battery of claim 1 , wherein the negative electrode active material is made of Si, and
wherein the lithium secondary battery has an N/P ratio of from 150% to 300%.

16 . The lithium secondary battery of claim 1 , wherein the lithium secondary battery has an energy density of 500 Wh/L or greater, and requires 20 minutes or less to charge up to 80% state of charge (SOC).

17 . The lithium secondary battery of claim 1 , further comprising a separator.

18 . The lithium secondary battery of claim 1 , further comprising at least one of an organic liquid electrolyte, an inorganic liquid electrolyte, a solid polymer electrolyte, a gel-type polymer electrolyte, a solid inorganic electrolyte, or a molten-type inorganic electrolyte.

Assignees

• Lg Energy Solution Ltd

Inventors

• Park Byung Chun
• Kwon Yo Han
• Kim Je Young
• Kim Seok Koo
• Jung Wang Mo
• Lee Yong Ju
• Lee Chul Haeng

Classifications

• Y02E60/10

  Energy storage using batteries · CPC title

• H01M2004/021

  Physical characteristics, e.g. porosity, surface area · CPC title

• H01M4/587

  for inserting or intercalating light metals · CPC title

• H01M4/386

  Silicon or alloys based on silicon · CPC title

• H01M4/483

  for non-aqueous cells (H01M4/485 takes precedence) · CPC title