Active material, nonaqueous electrolyte battery, battery pack, and vehicle

Patent metadata

Field	Value
Publication number	US-2017077509-A1
Application number	US-201615261540-A
Country	US
Kind code	A1
Filing date	Sep 9, 2016
Priority date	Sep 16, 2015
Publication date	Mar 16, 2017
Grant date	—

Abstract

According to one embodiment, an active material is provided. This active material includes active material particles each allowing lithium to be inserted thereinto and extracted therefrom in the range of 0.5 V to 2V (vs. Li + /Li), and carbon material layers at least partially coating the active material particles. The active material has a BET specific surface area S of 2 m 2 /g to 20 m 2 /g in accordance with a nitrogen adsorption method. Between the BET specific surface area S and the proportion M (mass %) of the mass of the carbon material layers to the total mass of the active material particles and carbon material layers, the ratio of S/M (m 2 /g) meets 0.5≦S/M≦5.

First claim

What is claimed is:

1 . An active material comprising:
active material particles each allowing lithium to be inserted thereinto and extracted therefrom in a range of 0.5 V to 2 V (vs. Li + /Li); and carbon material layers at least partially coating the active material particles, wherein a BET specific surface area S in a nitrogen adsorption method is 2 m 2 /g to 20 m 2 /g, and a ratio of S/M (m 2 /g) is 0.5≦S/M≦5 between the BET specific surface area S and a proportion M (mass %) of a mass of the carbon material layers to a total mass of the active material particles and the carbon material layers.

2 . The active material according to claim 1 , wherein the BET specific surface area S is 2 m 2 /g to 10 m 2 /g.

3 . The active material according to claim 1 , wherein the carbon material layers comprise 2 mass % or more of amorphous carbon.

4 . The active material according to claim 1 , wherein the active material particles comprise a titanium-containing metal composite oxide.

5 . The active material according to claim 1 , wherein the carbon material layers fall within a range of 0.5 nm to 15 nm in film thickness.

6 . A nonaqueous electrolyte battery comprising a positive electrode, a negative electrode comprising the active material according to claim 1 , and a nonaqueous electrolyte.

7 . A battery pack comprising the nonaqueous electrolyte battery according to claim 6 .

8 . The battery pack according to claim 7 , further comprising:
an external power distribution terminal; and a protective circuit.

9 . A battery pack comprising nonaqueous electrolyte batteries, each of the nonaqueous electrolyte batteries comprising:
a negative electrode comprising the active material according to claim 1 ; a positive electrode; and a nonaqueous electrolyte; wherein the nonaqueous electrolyte batteries are connected in series, in parallel or with a combination of series connection and parallel connection.

10 . A vehicle comprising the battery pack according to claim 7 .

11 . The vehicle according to claim 10 , wherein the battery pack is configured to recover a regenerative energy caused by a power of the vehicle.

Assignees

• Toshiba Kk

Inventors

• Ise Kazuki
• Harada Yasuhiro
• Takami Norio

Classifications

• H01M4/625

  Carbon or graphite · CPC title

• H01M10/0525

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

• H01M2004/027

  Negative electrodes · CPC title

• H01M10/056

  characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes · CPC title