Stacked battery

Patent metadata

Field	Value
Publication number	US-10559845-B2
Application number	US-201815952301-A
Country	US
Kind code	B2
Filing date	Apr 13, 2018
Priority date	Apr 28, 2017
Publication date	Feb 11, 2020
Grant date	Feb 11, 2020

Abstract

A main object of the present disclosure is to provide a stacked battery in which an unevenness of short circuit resistance among a plurality of cells is suppressed. The present disclosure achieves the object by providing a stacked battery comprising: a plurality of cells in a thickness direction, wherein the plurality of cells are electrically connected in parallel; each of the plurality of cells includes a cathode current collector, a cathode active material layer, a solid electrolyte layer, an anode active material layer, and an anode current collector, in this order; the stacked battery includes a surface-side cell that is located on a surface side of the stacked battery, and a center-side cell that is located on a center side rather than the surface-side cell; and the surface-side cell and the center-side cell satisfy at least one of: condition i) an electron conductivity of the cathode active material layer in the surface-side cell is less than an electron conductivity of the cathode active material layer in the center-side cell; and condition ii) an electron conductivity of the anode active material layer in the surface-side cell is less than an electron conductivity of the anode active material layer in the center-side cell.

First claim

What is claimed is:

1. A stacked battery comprising:
a plurality of cells in a thickness direction, wherein
the plurality of cells are electrically connected in parallel;
each of the plurality of cells includes a cathode current collector, a cathode active material layer, a solid electrolyte layer, an anode active material layer, and an anode current collector, in this order;
the stacked battery includes a surface-side cell that is located on a surface side of the stacked battery, and a center-side cell that is located on a center side rather than the surface-side cell; and
the surface-side cell and the center-side cell are configured to satisfy at least one of:
condition i) an electron conductivity of the cathode active material layer in the surface-side cell is C 1 and an electron conductivity of the cathode active material layer in the center-side cell is C 2 , a ratio of C 2 /C 1 is greater than or equal to 1.2 and less than or equal to 1000; and
condition ii) an electron conductivity of the anode active material layer in the surface-side cell is C 3 and an electron conductivity of the anode active material layer in the center-side cell is C 4 , a ratio of C 4 /C 3 is greater than or equal to 1.2 and less than or equal to 1000.

2. The stacked battery according to claim 1 , wherein a content of a conductive material in the cathode active material layer in the surface-side cell is less than a content of a conductive material in the cathode active material layer in the center-side cell.

3. The stacked battery according to claim 1 , wherein a content of a conductive material in the anode active material layer in the surface-side cell is less than a content of a conductive material in the anode active material layer in the center-side cell.

4. The stacked battery according to claim 1 , wherein: the anode active material layer includes a metal active material; and
a Li amount in the metal active material in the surface-side cell is less than a Li amount in the metal active material in the center-side cell.

5. The stacked battery according to claim 1 , wherein, when each of the plurality of cells is numbered as 1 st cell to N th cell, in which N≥3, in order along the thickness direction of the stacked battery,
the surface-side cell is a cell that belongs to a cell region A including 1 st cell to (N/3) th cell.

6. The stacked battery according to claim 5 , wherein the center-side cell is a cell that belongs to a cell region B including ((N/3)+1) th cell to (2N/3) th cell.

7. The stacked battery according to claim 6 , wherein an average electron conductivity of the cathode active material layer in the cell region A is less than an average electron conductivity of the cathode active material layer in the cell region B.

8. The stacked battery according to claim 6 , wherein an average electron conductivity of the anode active material layer in the cell region A is less than an average electron conductivity of the anode active material layer in the cell region B.

9. The stacked battery according to claim 1 , wherein, when each of the plurality of cells is numbered as 1 st cell to N th cell, in which N≥60, in order along the thickness direction of the stacked battery,
the surface-side cell is a cell that belongs to a cell region C including 1 st cell to 20 th cell.

10. The stacked battery according to claim 9 , wherein the center-side cell is a cell that belongs to a cell region D including 21 st cell to 40 th cell.

11. The stacked battery according to claim 10 , wherein an average electron conductivity of the cathode active material layer in the cell region C is less than an average electron conductivity of the cathode active material layer in the cell region D.

12. The stacked battery according to claim 10 , wherein an average electron conductivity of the anode active material layer in the cell region C is less than an average electron conductivity of the anode active material layer in the cell region D.

13. The stacked battery according to claim 1 , wherein the anode active material layer includes Si or a Si alloy as an anode active material.

Assignees

• Toyota Motor Co Ltd

Inventors

• Hasegawa Hajime
• Matsushita Yuki
• Nishimura Hideaki
• Okuhata Yusuke
• Ose Norihiro
• Tateishi Mitsuru
• Nagamatsu Shigetaka
• Uchiyama Takayuki
• Hama Shigenori
• Kato Dai
• Mashimo Naohiro
• Ebisuzaki Hideyo
• Kobayashi Ayano
• Fujimaki Hisataka

Classifications

• H01M2004/021

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

• H01M10/058 Primary

  Construction or manufacture · CPC title

• H01M4/386

  Silicon or alloys based on silicon · CPC title

• H01M4/624

  Electric conductive fillers · CPC title

• H01M10/0525 Primary

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