Anode active material for lithium secondary battery and lithium secondary battery including the same

Patent metadata

Field	Value
Publication number	US-12542273-B2
Application number	US-202318462432-A
Country	US
Kind code	B2
Filing date	Sep 7, 2023
Priority date	Oct 4, 2022
Publication date	Feb 3, 2026
Grant date	Feb 3, 2026

Abstract

An anode active material for a secondary battery includes a carbon-based active material, and silicon-based active material particles doped with magnesium. At least some of the silicon-based active material particles include pores, and a volume ratio of pores having a diameter of 50 nm or less among the pores is 2% or less based on a total volume of the silicon-based active material particles.

First claim

What is claimed is:

1 . An anode active material for a lithium secondary battery, comprising:
a carbon-based active material including artificial graphite and natural graphite; and silicon-based active material particles doped with magnesium, wherein at least some of the silicon-based active material particles include pores, and a volume ratio of pores having a diameter of 50 nm or less among the pores is in a range from 0.2% to 2% based on a total volume of the silicon-based active material particles, wherein a specific surface area of the silicon-based active material particles is 10.5 m2/g or less, wherein a minimum particle diameter (Dmin) of the silicon-based active material particles is greater than 0.3 μm, wherein a ratio of the content of natural graphite relative to the content of artificial graphite is 0.5 or less, and wherein a volume fraction of particles having a particle diameter of 2 μm or less among the silicon-based active material particles is 5% or less.

2 . The anode active material for a lithium secondary battery according to claim 1 , wherein a content of magnesium doped in the silicon-based active material particles is greater than 0 wt % and less than 25 wt % based on a total weight of the silicon-based active material particles.

3 . The anode active material for a lithium secondary battery according to claim 1 , wherein the silicon-based active material particles further include a carbon coating.

4 . The anode active material for a lithium secondary battery according to claim 1 , wherein the silicon-based active material particles are further doped with at least one element selected from the group consisting of Li, Al, Ca, Fe, Ti, Zn, La, Ce, Sn, Zr and Ru.

5 . The anode active material for a lithium secondary battery according to claim 1 , wherein a Mg1s spectrum of the silicon-based active material particles measured by an X-ray photoelectron spectroscopy (XPS), a ratio of a peak area of 1303 eV relative to a sum of a peak area of 1304.5 eV and the peak area of 1303 eV is 0.6 or less.

6 . The anode active material for a lithium secondary battery according to claim 1 , wherein a content of magnesium hydroxide present on surfaces of the silicon-based active material particles is 0.05 wt % or less based on a total weight of the silicon-based active material particles.

7 . The anode active material for a lithium secondary battery according to claim 1 , wherein a content of the silicon-based active material particles is in a range from 0.1 wt % to 30 wt % based on a total weight of the anode active material.

8 . The anode active material for a lithium secondary battery according to claim 1 , wherein a content of the carbon-based active material is in a range from 60 wt % to 99 wt % based on a total weight of the anode active material.

9 . An anode for a lithium secondary battery, comprising:
an anode current collector; and an anode active material layer formed on the anode current collector, the anode active material layer comprising the anode active material according to claim 1 .

10 . The anode for a lithium secondary battery according to claim 9 , further comprising a coating layer disposed between the anode current collector and the anode active material layer,
wherein the anode material layer and the coating layer each comprises a binder, and a content of the binder included in the coating layer is greater than a content of the binder included in the anode active material layer.

11 . The anode for a lithium secondary battery according to claim 10 , wherein the coating layer further comprises the anode active material.

12 . A lithium secondary battery, comprising:
the anode for a lithium secondary battery according to claim 9 ; and a cathode facing the anode for the lithium secondary battery.

13 . The anode active material for a lithium secondary battery according to claim 1 , wherein the carbon-based active material and the silicon-based active material particles are uniformly dispersed.

Assignees

• Sk On Co Ltd

Inventors

• Jang Hwan Ho
• Kim Moon Sung
• Kim Hyo Mi
• Ryu Sang Baek
• Park Da Hye
• Park Eun Jun
• Yook Seung Hyun
• Chung Da Bin
• Han Jun Hee

Classifications

• H01M10/0525

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

• H01M2004/027

  Negative electrodes · CPC title

• H01M2004/021

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

• H01M4/583

  Carbonaceous material, e.g. graphite-intercalation compounds or CFx · CPC title

• H01M4/58

  of inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy; of polyanionic structures, e.g. phosphates, silicates or borates · CPC title