Synthesis of crystalline nanometric LiFeMPO4

Patent metadata

Field	Value
Publication number	US-9051184-B2
Application number	US-201113267135-A
Country	US
Kind code	B2
Filing date	Oct 6, 2011
Priority date	Dec 22, 2006
Publication date	Jun 9, 2015
Grant date	Jun 9, 2015

Abstract

The invention relates to crystalline nanometric olivine-type LiFe 1-x M x PO 4 powder with M being Co and/or Mn, and 0≦x≦1, with small particle size and narrow particle size distribution. A direct precipitation process is described, comprising the steps of: providing a water-based mixture having at a pH between 6 and 10, containing a dipolar aprotic additive, and Li (I) , Fe (II) , P (V) , and Co (II) and/or Mn (II) as precursor components; heating said water-based mixture to a temperature less than or equal to its boiling point at atmospheric pressure, thereby precipitating crystalline LiFe 1-x M x PO 4 powder. An extremely fine particle size is obtained of about 80 nm for Mn and 275 nm for Co, both with a narrow distribution.

First claim

The invention claimed is:

1. A process for preparing crystalline LiFe 1-x M x PO 4 powder where M is one or both of Co and Mn, and 0<x<1, comprising the steps of:
providing a water-based mixture having a pH between 6 and 10, and containing a dipolar aprotic additive and Li (I) , Fe (II) , P (V) and one or both of Co (II) and Mn (II) as precursor components; and
heating said water-based mixture to a temperature less than or equal to its boiling point at atmospheric pressure, thereby precipitating crystalline LiFe 1-x M x PO 4 powder.

2. The process of claim 1 , further comprising a step of post-treatment of the LiFe 1-x M x PO 4 powder comprising heating it in non-oxidizing conditions.

3. The process of claim 2 , wherein the step of post-treatment of the LiFe 1-x M x PO 4 is performed at a temperature of up to 675° C.

4. The process of claim 2 , wherein the post treatment by heating in non-oxidizing atmosphere takes place in the presence of at least one further component, wherein said component is a carbon containing or electron conducting substance or a precursor of an electron conducting substance.

5. The process of claim 4 , wherein the electron conducting substance is conductive carbon or carbon fibers.

6. The process of claim 4 , wherein the precursor of an electron conducting substance is a polymer or sugar-type macromolecule.

7. The process of claim 1 , wherein the precipitation of the crystalline LiFe 1-x M x PO 4 powder takes place in the presence of at least one further component, Wherein said component is a carbon containing or election conducting substance or a precursor of an electron conducting substance.

8. The process of claim 7 , wherein the electron conducting substance is conductive carbon or carbon fibers.

9. The process of claim 7 , wherein the precursor of an electron conducting substance is a polymer or sugar-type macromolecule.

10. The process of claim 1 , wherein at least part of the Li (I) is introduced as LiOH.

11. The process of claim 10 , wherein at least part of the P (V) is introduced as H 3 PO 4 .

12. The process of claim 11 , wherein the pH of the water-based mixture is reached by adjusting the ratio of LiOH to H 3 PO 4 .

13. The process of claim 1 , wherein the atmospheric boiling point of the water-based mixture is between 100 and 150° C.

14. The process of claim 1 , wherein the dipolar aprotic additive is dimethylsulfoxide.

Assignees

• Levasseur Stéphane
• Van Thournout Michèle
• Gibot Pierre
• Masquelier Christian
• Umicore Nv
• Centre Nat Rech Scient

Inventors

• Levasseur Stéphane
• Van Thournout Michèle
• Gibot Pierre
• Masquelier Christian

Classifications

• Y02E60/10

  Energy storage using batteries · CPC title

• H01M4/02

  Electrodes composed of, or comprising, active material · CPC title

• H01M4/136

  Electrodes based on inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy · CPC title

• C01B25/45 Primary

  containing plural metal, or metal and ammonium · CPC title

• Y02E60/122

  Cross-Sectional Technologies · mapped topic