Anode active material comprising metal phosphide coating on surface of carbon material, preparation method therefor, nonaqueous lithium secondary battery comprising anode active material, and manufacturing method therefor

Patent metadata

Field	Value
Publication number	US-12107264-B2
Application number	US-202017595157-A
Country	US
Kind code	B2
Filing date	May 13, 2020
Priority date	May 13, 2019
Publication date	Oct 1, 2024
Grant date	Oct 1, 2024

Abstract

The present invention provides a method for preparing an anode active material for a nonaqueous lithium secondary battery, comprising the steps of: preparing a carbon-based material; forming a precursor coating layer comprising Me and A (wherein A is O or S) on the surface of the carbon-based material; supplying a P precursor to the precursor coating layer of the carbon-based material; and converting at least a part of the precursor coating layer into a compound represented by Me x1 P y1 (wherein x1>0 and y1>0) by the reaction of the precursor coating layer and the P precursor, thereby forming a phosphide coating layer, wherein Me is at least one type of the same metal element selected from among Mo, Ni, Fe, Co, Ti, V, Cr, Nb and Mn.

First claim

What is claimed is:

1. A method for preparing an anode active material for a nonaqueous lithium secondary battery, the method comprising:
preparing a carbon-based material;
forming a precursor coating layer containing Me and A (A is O or S) on the surface of the carbon-based material;
supplying a P precursor to the precursor coating layer on the carbon-based material; and
reacting the precursor coating layer and the P precursor to convert at least a portion of the precursor coating layer into a compound represented by chemical formula Me x1 P y1 (x1>0 and y1>0), thereby forming a phosphide coating layer,
wherein Me is at least one same metal element selected from Mo, Ni, Fe, Co, Ti, V, Cr, Nb, and Mn.

2. The method of claim 1 , wherein the phosphide coating layer contains a composite of a compound represented by chemical formula Me x1 P y1 (x1>0 and y1>0) and a compound represented by chemical formula Me x2 A y2 (A is O or S; and x2>0 and y2>0).

3. The method of claim 1 , wherein in the supplying of the P precursor, the P precursor is supplied as a gas source.

4. The method of claim 1 , wherein in the supplying of the P precursor, the P precursor is mixed, as a solid or liquid source, with the carbon-based material.

5. The method of claim 1 , wherein the P precursor is at least one type selected from the group consisting of sodium hypophosphite (NaH 2 PO 2 ), phosphoric acid (H 3 PO 4 ), phosphorous trichloride (PCl 3 ), phosphorous, red (P), Phosphorous, black (P), and triphenyl phosphine (C 18 H 15 P).

6. The method of claim 1 , wherein in the forming of the coating layer, heat treatment is conducted for reaction of the precursor coating layer and the P precursor.

7. The method of claim 1 , wherein in the converting, P of the P precursor is substituted for A in the precursor coating layer.

8. The method of claim 1 , wherein the P precursor contains no metal element Me.

9. The method of claim 1 , wherein the forming of the phosphide coating layer is performed in an inert gas atmosphere at 500-1000° C. for 1-10 hours.

Assignees

• Keri Korea Electrotechnology Res Inst
• Univ Industry Cooperation Group Kyung Hee Univ

Inventors

• Lee Sang Min
• Park Min-Sik
• Lee Chul Ho
• Choi Jeong Hee

Classifications

• H01M2004/027

  Negative electrodes · CPC title

• H01M2004/021

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

• H01M4/587

  for inserting or intercalating light metals · CPC title

• H01M4/5805

  Phosphides · CPC title

• C01P2006/40

  Electric properties · CPC title