Energy storage device, energy storage apparatus, vehicle, and method for using energy storage device

Patent metadata

Field	Value
Publication number	US-9705119-B2
Application number	US-201514719886-A
Country	US
Kind code	B2
Filing date	May 22, 2015
Priority date	May 26, 2014
Publication date	Jul 11, 2017
Grant date	Jul 11, 2017

Abstract

An energy storage device comprises a positive electrode, a negative electrode, a separator arranged between the positive electrode and the negative electrode, and a nonaqueous electrolyte. The negative electrode has a negative substrate layer, and a negative composite layer arranged on the surface of the negative substrate layer. The separator has a separator substrate layer. The negative composite layer contains a non-graphitizable carbon having a particle diameter D50 of 2.0 μm or more and 6.0 μm or less. A corrected negative electrode density, which is defined as a value obtained by dividing, by a thickness of the separator substrate layer, a value obtained by multiplying a density of the negative composite layer by a thickness of the negative composite layer, is 1.2 (g/cm 3 ) or more and 5.1 (g/cm 3 ) or less.

First claim

What is claimed is:

1. An energy storage device comprising:
a positive electrode;
a negative electrode;
a separator arranged between the positive electrode and the negative electrode; and
a nonaqueous electrolyte,
wherein the negative electrode has a negative substrate layer, and a negative composite layer arranged on the surface of the negative substrate layer,
the separator has a separator substrate layer,
the negative composite layer contains a non-graphitizable carbon having a particle diameter D50 of 2.0 μm or more and 6.0 μm or less, and
a corrected negative electrode density, which is defined as a value obtained by dividing, by a thickness of the separator substrate layer, a value obtained by multiplying a density of the negative composite layer by a thickness of the negative composite layer, is 1.2 (g/cm 3 ) or more and 5.1 (g/cm 3 ) or less.

2. The energy storage device according to claim 1 ,
wherein a ratio of PC impregnation of the separator, which represents a mass ratio between propylene carbonate contained in the separator by impregnation and the separator, is 40% or more and 70% or less.

3. The energy storage device according to claim 1 ,
wherein the corrected negative electrode density is 2.2 (g/cm 3 ) or more and 4.4 (g/cm 3 ) or less.

4. The energy storage device according to claim 1 ,
wherein the separator has a thickness of 26 μm or less.

5. The energy storage device according to claim 1 ,
wherein the separator further has an inorganic layer containing inorganic particles on the surface of the separator substrate layer.

6. An energy storage apparatus comprising:
an energy storage device; and
a bus bar member electrically connected to the energy storage device, wherein
the energy storage device comprises:
a positive electrode;
a negative electrode;
a separator arranged between the positive electrode and the negative electrode; and
a nonaqueous electrolyte,

the negative electrode has a negative substrate laver, and a negative composite layer arranged on the surface of the negative substrate layer,
the separator has a separator substrate layer,
the negative composite layer contains a non-graphitizable carbon having a particle diameter D50 of 2.0 μm or more and 6.0 μm or less, and
a corrected negative electrode density, which is defined as a value obtained by dividing, by a thickness of the separator substrate layer, a value obtained by multiplying a density of the negative composite layer by a thickness of the negative composite layer, is 1.2 (g/cm 3 ) or more and 5.1 (g/cm 3 ) or less.

7. A method for charging or discharging an energy storage device, the method comprising:
providing the energy storage device comprising a positive electrode, a negative electrode, a separator arranged between the positive electrode and the negative electrode, and a nonaqueous electrolyte; and
at least one selected from the group consisting of charging and discharging the energy storage device, the charging comprising introducing electricity in an internal space of the energy storage device to store the electricity within the positive electrode, the negative electrode and the separator at 8 CA or more when an available discharge capacity is defined as 1CAh, the discharging comprising leading the electricity stored in the positive electrode, the negative electrode and the separator to an external space of the energy storage device at 8 CA or more when the available discharge capacity is defined as 1CAh, wherein
the negative electrode has a negative substrate layer, and a negative composite layer arranged on the surface of the negative substrate layer,
the separator has a separator substrate layer,
the negative composite layer contains a non-graphitizable carbon having a particle diameter D50 of 2.0 μm or more and 6.0 μm or less, and
a corrected negative electrode density, which is defined as a value obtained by dividing, by a thickness of the separator substrate layer, a value obtained by multiplying a density of the negative composite layer by a thickness of the negative composite layer, is 1.2 (g/cm 3 ) or more and 5.1 (g/cm 3 ) or less.

Assignees

• Gs Yuasa Int Ltd

Inventors

• Miyazaki Akihiko
• Mori Sumio
• Kako Tomonori
• Nakai Kenta

Classifications

• H01M50/454

  comprising a non-fibrous layer and a fibrous layer superimposed on one another · CPC title

• H01M50/46 Primary

  Separators, membranes or diaphragms characterised by their combination with electrodes · CPC title

• H01M50/505

  comprising a single busbar · CPC title

• H01M2010/4292

  Aspects relating to capacity ratio of electrodes/electrolyte or anode/cathode · CPC title

• H01M50/54

  Connection of several leads or tabs of plate-like electrode stacks, e.g. electrode pole straps or bridges · CPC title