Nanometric anatase lattice stabilised by cation vacancies, methods for the production thereof, and uses of same

Patent metadata

Field	Value
Publication number	US-10680241-B2
Application number	US-201515528140-A
Country	US
Kind code	B2
Filing date	Nov 20, 2015
Priority date	Nov 20, 2014
Publication date	Jun 9, 2020
Grant date	Jun 9, 2020

Abstract

The present application describes a process for the preparation of titanium-based compounds having an anatase type structure with cationic vacancies arising from a partial substitution of oxygen atoms by fluorine atoms and hydroxyl groups. Electrochemically active materials comprising the titanium-based compounds for use in lithium-ion battery electrodes are also described.

First claim

The invention claimed is:

1. A titanium-based compound of the general chemical formula:
Ti 1-x-y □ x+y F 4x (OH) 4y O 2-4(x+y)

wherein,
□ represents a cationic vacancy; and
x and y are numbers such that 0.01≤(x+y)<0.5, wherein x and y are not zero, and wherein the titanium-based compound has an anatase type structure.

2. The titanium-based compound according to claim 1 , wherein x and y are numbers such that 0.04≤(x+y)<0.5.

3. The titanium-based compound according to claim 1 , which is Ti 0.78 □ 0.22 F 0.4 (OH) 0.48 O 1.12 .

4. An electrochemically active material comprising the titanium-based compound of claim 1 .

5. An electrode comprising the electrochemically active material of claim 4 on a current collector.

6. A lithium-ion battery comprising the electrode of claim 5 , a counter-electrode and an electrolyte between the electrode and the counter-electrode.

7. A method for preparing a titanium-based compound having an anatase type structure with cationic vacancies arising from a partial substitution of oxygen atoms by fluorine atoms and hydroxyl groups, comprising the steps of:
a) preparing a solution containing a titanium precursor, a fluorinating agent and a solvent; and
b) precipitating a titanium-based compound having the general chemical formula Ti 1-x-y □ x+y F 4x (OH) 4y O 2-4(x+y) , wherein represents a cationic vacancy, wherein x and y are numbers such that 0.01≤(x+y)<0.5, and wherein x and y are not zero.

8. The method according to claim 7 , wherein the titanium precursor is selected from titanium C 2 -C 10 alkoxides and titanium chloride.

9. The method according to claim 7 , wherein the fluorinating agent is an agent which provides fluoride anions.

10. The method according to claim 7 , wherein the solvent of the solution of step (a) comprises an organic solvent or a mixture of an organic solvent and water.

11. The method according to claim 10 , wherein the organic solvent is selected from C 1 -C 10 alcohols, dialkylketones, ethers, esters or a combination thereof.

12. The method according to claim 10 , wherein the organic solvent is methanol, ethanol, isopropanol, butanol, octanol or a combination thereof.

13. The method according to claim 7 , wherein step (a) or (b) further comprises a thermal treatment.

14. The method according to claim 13 , wherein the thermal treatment comprises heating the solution of step (a) at a temperature within the range of from about 50° C. to about 220° C.

15. The method of claim 13 , wherein a degree of cationic vacancies is controlled by adjusting the temperature of the thermal treatment.

16. The method according to claim 11 , wherein the dialkylketones are acetone.

17. The method of claim 7 , wherein x and y are numbers such that 0.04≤(x+y)<0.5.

18. A titanium-based compound prepared by the process method according to claim 7 , wherein said compound is of the general chemical formula:
Ti 1-x-y □ x+y F 4x (OH) 4y O 2-4(x+y)

wherein,
□ represents a cationic vacancy; and
x and y are numbers such that 0.01≤(x+y)<0.5, and wherein x and y are not zero.

Assignees

• Hydro Quebec
• Univ Pierre Et Marie Curie Paris 6
• Centre Nat Rech Scient

Inventors

• Dambournet Damien
• Li Wei
• Groult Henri
• Leclerc Sandrine
• Julien Christian
• Zaghib Karim

Classifications

• C01G23/002

  Compounds containing titanium, with or without oxygen or hydrogen, and containing two or more other elements (C01G23/001, C01G23/003 take precedence) · CPC title

• C30B29/16

  Oxides · CPC title

• H01M4/485 Primary

  of mixed oxides or hydroxides for inserting or intercalating light metals, e.g. LiTi2O4 or LiTi2OxFy (H01M4/505, H01M4/525 take precedence) · CPC title

• C01P2006/40

  Electric properties · CPC title

• C01G23/00 Primary

  Compounds of titanium {(preparation of Ti-compounds from ores or scraps C22B34/12)} · CPC title