Negative electrode active material for secondary battery and method for manufacturing same

Patent metadata

Field	Value
Publication number	US-2019326594-A1
Application number	US-201916460612-A
Country	US
Kind code	A1
Filing date	Jul 2, 2019
Priority date	Apr 9, 2014
Publication date	Oct 24, 2019
Grant date	—

Abstract

Provided is an anode active material for a secondary battery and a method of fabricating the anode active material. A silicon-based active material composite according to an embodiment of the inventive concept includes silicon and silicon oxide obtained by oxidizing at least a part of the silicon, and an amount of oxygen with respect to a total weight of the silicon and the silicon oxide is restricted to 9 wt % to 20 wt %.

First claim

1 - 16 . (canceled)

17 . A secondary particle comprising agglomerated primary particles and a carbon-based conductive material for electrically connecting the agglomerated primary particles,
wherein an average diameter of the primary particles is 30 to 300 nm, wherein each of the primary particles comprises a silicon core and a shell of silicon oxide surrounding the core, and wherein the amount of oxygen in the primary particles with respect to the total weight of the silicon and the silicon oxide in the primary particles is 9 to 20 wt %.

18 . The secondary particle of claim 17 , wherein the average diameter of the primary particles is 30 to 200 nm.

19 . The secondary particle of claim 17 , wherein the shell of silicon oxide has a thickness of 2 to 30 nm.

20 . The secondary particle of claim 17 , wherein the shell of silicon oxide has a thickness of 3 to 15 nm.

21 . The secondary particle of claim 17 , wherein the amount of oxygen in the primary particles with respect to the total weight of the silicon and the silicon oxide in the primary particles is 10 to 20 wt %.

22 . The secondary particle of claim 17 , wherein the silicon core has a low crystallinity.

23 . The secondary particle of claim 17 , wherein the silicon oxide shell is formed on the silicon core of each of the primary particles by chemically oxidizing silicon particles by grinding a slurry of the silicon particles in a liquid solvent comprising oxygen.

24 . The secondary particle of claim 17 , wherein the carbon-based conductive material is formed by dispersing the primary particles in a solvent comprising a polymeric precursor of the carbon-based conductive material to obtain intermediate particles wet by the polymeric precursor, drying the intermediate particles, and heat treating to obtain the carbon-based conductive material.

25 . The secondary particle of claim 17 , wherein the carbon-based conductive material is formed of crystalline carbon, soft carbon, graphite, graphene, or amorphous carbon.

26 . The secondary particle of claim 17 , wherein the carbon-based conductive material has a greater mole fraction of sp 2 carbon than sp 3 carbon.

27 . The secondary particle of claim 17 , wherein the carbon-based conductive material is a layer at the outermost portion of the primary particles.

28 . The secondary particle of claim 27 , wherein the carbon-based conductive material is formed of crystalline carbon, soft carbon, graphite, graphene, or amorphous carbon.

29 . The secondary particle of claim 28 , wherein the carbon-based conductive material has a greater mole fraction of sp 2 carbon than sp 3 carbon.

Assignees

• Nexeon Ltd

Inventors

• Cho Young Tai
• Park Seung Chul
• Park Seon
• Park Jee Hye
• Lee Yong Eui
• Kim Chul Hwan
• Seo Hee Young

Classifications

• H01M4/134

  Electrodes based on metals, Si or alloys · CPC title

• H01M4/483

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

• H01M4/1395

  of electrodes based on metals, Si or alloys · CPC title

• H01M4/131

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

• H01M4/1391

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