Active material containing an Nb2TiO7 phase, electrode, secondary battery, battery pack, and vehicle

Patent metadata

Field	Value
Publication number	US-10862118-B2
Application number	US-201816117978-A
Country	US
Kind code	B2
Filing date	Aug 30, 2018
Priority date	Mar 23, 2018
Publication date	Dec 8, 2020
Grant date	Dec 8, 2020

Abstract

An active material includes an Nb 2 TiO 7 phase and at least one Nb-rich phase selected from an Nb 10 Ti 2 O 29 phase, an Nb 14 TiO 37 phase, and an Nb 24 TiO 64 phase. The active material satisfies a peak intensity ratio represented by the following Formula (1): 0<I B /I A ≤0.25 (1). In Formula (1), I A is a peak intensity of the maximum peak attributed to the Nb 2 TiO 7 phase and appealing at 2θ of 26.0±0.1° in a wide angle X-ray diffraction pattern under CuKα rays as an X-ray source, and I B is a peak intensity of the maximum peak attributed to the at least one Nb-rich phase and appearing at 2θ of 24.9±0.2° in the diffraction pattern.

First claim

What is claimed is:

1. An active material comprising:
an Nb 2 TiO 7 phase; and
at least one Nb-rich phase selected from a would consisting of an Nb 10 Ti 2 O 29 phase, an Nb 14 TiO 37 phase, and an Nb 24 TiO 64 phase,
wherein the active material comprises mixed-phase active material particles comprising: a shell part formed of the Nb 2 TiO 7 phase; and a core part surrounded by the shell part and formed of the at least one Nb-rich phase,
the mixed-phase active material particles further comprises an intermediate part interposed between the core part and the shell part,
the intermediate part comprises the Nb 2 TiO 7 phase and the at least one Nb-rich phase and has a concentration gradient of the Nb 2 TiO 7 phase rising from a side of the core part to a side of the shell part, and
the active material satisfies a peak intensity ratio represented by Formula (I):
0< I B /I A ≤0.25  (1)

wherein in the Formula (1), I A is a peak intensity of a maximum peak attributed to the Nb 2 TiO 7 phase and appearing at 2θ of 26.0±0.1° in a wide angle X-ray diffraction pattern under a CuKα ray as an X-ray source, and I B is a peak intensity of a maximum peak attributed to the at least one Nb-rich phase and appearing at 2θ of 24.9±0.2° in the diffraction pattern.

2. The active material according to claim 1 , satisfying Formula (2):
0.01≤ I B /I A ≤0.25  (2)

3. The active material according to claim 1 , wherein the Nb 2 TiO 7 phase and the at least one Nb-rich phase interpenetrate each other in at least a part of the intermediate part.

4. An electrode comprising the active material according to claim 1 .

5. The electrode according to claim 4 , wherein the electrode comprises an active material-containing layer comprising the active material.

6. A secondary battery comprising:
a positive electrode;
a negative electrode; and
an electrolyte,
wherein the negative electrode is the electrode according to claim 4 .

7. A battery pack comprising the secondary 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. The battery pack according to claim 7 , comprising
plural of the secondary battery, wherein the secondary batteries are electrically connected in series, in, parallel, or in a combination of in series and in parallel.

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

11. The vehicle according to claim 10 , which comprises a mechanism configured to convert kinetic energy of the vehicle into regenerative energy.

Assignees

• Toshiba Kk
• Toshiba Infrastructure Systems & Solutions Corp

Inventors

• Harada Yasuhiro
• Takami Norio
• Sasakawa Tetsuya
• Namiki Yusuke
• Yamashita Yasunobu

Classifications

• H01M50/289

  characterised by spacing elements or positioning means within frames, racks or packs (spacing elements inside cells other than separators, membranes or diaphragms H01M50/471) · CPC title

• H01M50/284

  with incorporated circuit boards, e.g. printed circuit boards [PCB] · CPC title

• H01M50/553

  Terminals adapted for prismatic, pouch or rectangular cells · CPC title

• H01M50/55

  on the same side of the cell · CPC title

• H01M50/271

  Lids or covers for the racks or secondary casings · CPC title