Active material, electrode, secondary battery, battery pack, and vehicle

Patent metadata

Field	Value
Publication number	US-2020091513-A1
Application number	US-201916289043-A
Country	US
Kind code	A1
Filing date	Feb 28, 2019
Priority date	Sep 14, 2018
Publication date	Mar 19, 2020
Grant date	—

Abstract

According to one embodiment, an active material is provided. The active material includes a primary particle containing a phosphorus-containing monoclinic niobium-titanium composite oxide. The primary particle has a concentration gradient in which a phosphorus concentration increases from the gravity point of the primary particle toward the surface of the primary particle.

First claim

What is claimed is:

1 . An active material comprising
a primary particle comprising a phosphorus-containing monoclinic niobium-titanium composite oxide, wherein the primary particle has a concentration gradient in which a phosphorus concentration increases from a gravity point of the primary particle toward a surface of the primary particle.

2 . The active material according to claim 1 ,
wherein the phosphorus-containing monoclinic niobium-titanium composite oxide has an average composition represented by a general formula Ti 1-x M1 x Nb 2-y-z M2 y P z O 7 , where 0≤x<1, 0≤y<1, 0<z≤0.5, each of elements M 1 and M 2 is at least one selected from the group consisting of V, Ta, Fe, Bi, Cr, Mo, W, B, K, Na, Mg, Al, and Si, and the element M 1 and the element M 2 may be the same element or different elements from each other.

3 . The active material according to claim 1 , wherein a ratio (C 2 /C 1 ) of a phosphorus concentration (C 2 ) at a position corresponding to 800 of a length defined from the gravity point to the surface of the primary particle, with respect to a phosphorus concentration (C 1 ) at a position of the gravity point of the primary particle is in a range of 1.05 to 100.

4 . The active material according to claim 1 , wherein a phosphate compound is present at least a part of the surface of the primary particle.

5 . The active material according to claim 4 , comprising
a secondary particle formed of a plurality of the primary particle, wherein the phosphate compound is present between the primary particles.

6 . The active material according to claim 4 , wherein the phosphate compound comprises at least one selected from the group consisting of phosphorus oxide, iron phosphate, and potassium phosphate.

7 . The active material according to claim 6 , wherein the phosphate compound comprises at least one selected from the group consisting of iron phosphate and potassium phosphate.

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

9 . The electrode according to claim 8 , wherein the electrode comprises an active material-containing layer comprising the active material.

10 . A secondary battery comprising:
a positive electrode; a negative electrode; and an electrolyte, wherein the negative electrode is the electrode according to claim 8 .

11 . A battery pack comprising the secondary battery according to claim 10 .

12 . The battery pack according to claim 11 , further comprising
an external power distribution terminal; and a protective circuit.

13 . The battery pack according to claim 11 , comprising a plurality of the secondary battery, wherein the secondary batteries are electrically connected in series, in parallel, or in combination of in series and in parallel.

14 . A vehicle comprising the battery pack according to claim 11 .

15 . The vehicle according to claim 14 , comprising 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
• Yamashita Yasunobu
• Yoshima Kazuomi

Classifications

• B60L50/64

  Constructional details of batteries specially adapted for electric vehicles · CPC title

• B60L7/10 Primary

  Dynamic electric regenerative braking (B60L7/22 takes precedence) · CPC title

• H01M10/4257

  Smart batteries, e.g. electronic circuits inside the housing of the cells or batteries · CPC title

• H01M4/366

  as layered products · 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