Negative electrode material, negative electrode for lithium ion secondary battery, lithium ion secondary battery, and method of manufacturing the same

Patent metadata

Field	Value
Publication number	US-9899673-B2
Application number	US-201415311220-A
Country	US
Kind code	B2
Filing date	May 19, 2014
Priority date	May 19, 2014
Publication date	Feb 20, 2018
Grant date	Feb 20, 2018

Abstract

The invention addresses the problem of providing a lithium ion secondary battery excellent in initial charge-discharge characteristics and life characteristics. To solve the above problem, the invention provides a lithium ion secondary battery in which an electrode group having a positive electrode and a negative electrode is housed in a battery can, wherein the negative electrode includes a negative electrode active material supported on a negative electrode foil, and the negative electrode active material includes cores having SiO as a main component, a composite oxide coating layer of Fe and SiO 2 disposed on the periphery of each of the cores, and a carbon coating layer disposed on the periphery of the composite oxide coating layer of Fe and SiO 2 .

First claim

The invention claimed is:

1. A lithium ion secondary battery in which an electrode group having a positive electrode and a negative electrode is housed in a battery can, wherein
the negative electrode includes a negative electrode active material supported on a negative electrode foil, and
the negative electrode active material includes a core having SiO as a main component, a composite oxide coating layer of Fe and SiO2 disposed on a periphery of the core, and a carbon coating layer disposed on a periphery of the composite oxide coating layer of Fe and SiO2; and
a thickness of the oxide coating layer of Fe and SiO2 is not less than 5 nm and not more than 1 μm.

2. The lithium ion secondary battery according to claim 1 , wherein
the mass of SiO is larger than the mass of Fe in the negative electrode active material.

Assignees

• Hitachi Ltd

Inventors

• Tanaka Naokage
• Hoshi Kento
• Suzuki Shuichi
• Haruna Hiroshi

Classifications

• H01M2004/027

  Negative electrodes · CPC title

• H01M4/587

  for inserting or intercalating light metals · CPC title

• H01M10/0525

  Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries · CPC title

• H01M4/523

  for non-aqueous cells (H01M4/525 takes precedence) · CPC title

• H01M2004/021

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