Active material, method for manufacturing active material, electrode, lithium ion secondary battery, and method for manufacturing lithium ion secondary battery

Patent metadata

Field	Value
Publication number	US-10611639-B2
Application number	US-201214005357-A
Country	US
Kind code	B2
Filing date	Mar 30, 2012
Priority date	Mar 31, 2011
Publication date	Apr 7, 2020
Grant date	Apr 7, 2020

Abstract

A method for manufacturing an active material, capable of improving the discharge capacity of a lithium ion secondary battery is provided. The method for manufacturing an active material according to the present invention includes a first step of heating a mixture solution including a lithium source, a phosphate source, a vanadium source, and water under pressure to generate a precursor in the mixture solution, and adjusting the pH of the mixture solution including the precursor to be 6 to 8; and a second step of heating the precursor at 425 to 650° C. after the first step to generate an active material.

First claim

The invention claimed is:

1. A method for manufacturing an active material, comprising:
heating a mixture solution that comprises a lithium source, a phosphate source, a vanadium source, a reducing agent, Nb 2 O 5 , and water at a temperature of 150° C. to 190° C. under pressure to generate a precursor in the mixture solution; and then
adjusting the pH of the mixture solution including the precursor to be 6 to 8; and then
heating the precursor at 425 to 650° C. to generate an active material;
wherein the reducing agent is hydrazine monohydrate.

2. A method for manufacturing a lithium ion secondary battery, comprising:
forming an electrode comprising a current collector and an active material layer stacked on the current collector, the active material layer being formed by applying a coating material on the current collector, the coating material comprising:
the active material obtained by the method according to claim 1 ,
a binder,
a solvent, and
a conductive auxiliary agent.

3. An active material comprising β-type crystal of LiVOPO 4 , wherein distortion in <100>direction in the β-type crystal is 1.2% or less.

4. An electrode comprising a current collector and an active material layer stacked on the current collector, wherein the active material layer includes the active material according to claim 3 .

5. The electrode according to claim 4 , wherein the active material layer further includes carbon with a tap density of 0.03 to 0.09 g/ml and carbon with a tap density of 0.1 to 0.3 g/ml.

6. A lithium ion secondary battery comprising the electrode according to claim 4 .

7. A lithium ion secondary battery comprising the electrode according to claim 5 .

Assignees

• Sano Atsushi
• Otsuki Keitaro
• Kato Tomohiko
• Nojima Akinobu
• Higuchi Akiji
• Tdk Corp

Inventors

• Sano Atsushi
• Otsuki Keitaro
• Kato Tomohiko
• Nojima Akinobu
• Higuchi Akiji

Classifications

• H01M4/5825

  Oxygenated metallic salts or polyanionic structures, e.g. borates, phosphates, silicates, olivines · CPC title

• H01M10/052

  Li-accumulators · CPC title

• H01M4/1397

  of electrodes based on inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy · 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

• H01M10/0585

  of accumulators having only flat construction elements, i.e. flat positive electrodes, flat negative electrodes and flat separators · CPC title