Thermal insulation material for battery pack and battery pack

Patent metadata

Field	Value
Publication number	US-12388133-B2
Application number	US-202117599799-A
Country	US
Kind code	B2
Filing date	Feb 3, 2021
Priority date	Mar 12, 2020
Publication date	Aug 12, 2025
Grant date	Aug 12, 2025

Abstract

A thermal insulation material for a battery pack includes: a thermal insulation layer; and a first base material and a second base material that are arranged with the thermal insulation layer interposed therebetween. The thermal insulation layer contains a porous structure in which a plurality of particles is connected to form a skeleton, reinforcing fibers, and metal oxide nanoparticles serving as a binder, the porous structure having pores inside and having hydrophobic sites at least on a surface of the porous structure out of the surface and inside of the porous structure, and a percentage mass loss of the thermal insulation layer in thermogravimetric analysis in which the thermal insulation layer is held at 500° C. for 30 minutes is 10% or less.

First claim

The invention claimed is:

1. A thermal insulation material for a battery pack, the thermal insulation material comprising:
a thermal insulation layer; and
a first base material and a second base material that are arranged with the thermal insulation layer interposed between the first and second base materials, wherein
the thermal insulation layer contains a porous structure in which a plurality of particles is connected to form a skeleton, reinforcing fibers, metal oxide nanoparticles serving as a binder, and polyethylene oxide as a thickener, the porous structure having pores inside and having hydrophobic sites at least on a surface of the porous structure out of the surface and inside of the porous structure, and a percentage mass loss of the thermal insulation layer in thermogravimetric analysis in which the thermal insulation layer is held at 500° C. for 30 minutes is 10% or less,
in a state in which a compression test is performed in which the thermal insulation material is compressed under a load of 15 MPa in a thickness direction that is a stacking direction of the thermal insulation layer, the first base material, and the second base material, a rate of change of a thickness of the thermal insulation material after the compression test relative to the thickness before the compression test is less than 70%,
an average particle size of the porous structure is 1 μm or more and 200 μm or less, and
the reinforcing fibers are intertwined around the porous structure.

2. The thermal insulation material for a battery pack according to claim 1 , wherein the nanoparticles are silica particles.

3. The thermal insulation material for a battery pack according to claim 1 , wherein the porous structure is silica aerogel in which a plurality of silica particles is connected to form a skeleton.

4. The thermal insulation material for a battery pack according to claim 1 , wherein a content of the porous structure in the thermal insulation layer is 150 parts by mass or more and 280 parts by mass or less per 100 parts by mass of components other than the porous structure and the reinforcing fibers.

5. The thermal insulation material for a battery pack according to claim 1 , wherein the reinforcing fibers are one or more types of fibers selected from glass fibers and alumina fibers.

6. The thermal insulation material for a battery pack according to claim 1 , wherein a content of the reinforcing fibers in the thermal insulation layer is 5 parts by mass or more and 200 parts by mass or less per 100 parts by mass of the components other than the porous structure and the reinforcing fibers.

7. The thermal insulation material for a battery pack according to claim 1 , wherein the reinforcing fibers have a diameter of 6.5 μm or more and 18 μm or less and a length of 3 mm or more and 25 mm or less.

8. The thermal insulation material for a battery pack according to claim 1 , wherein either or both of the first base material and the second base material is a glass cloth.

9. The thermal insulation material for a battery pack according to claim 1 , wherein the thermal insulation material has a body portion in which the first base material and the second base material are stacked with the thermal insulation layer interposed between the first and second base materials, and a peripheral edge portion in which the first base material and the second base material overlap each other, the peripheral edge portion being located around the thermal insulation layer.

10. The thermal insulation material for a battery pack according to claim 9 , wherein the first base material and the second base material are fused in the peripheral edge portion.

11. The thermal insulation material for a battery pack according to claim 9 , wherein a fixing member that fixes the first base material and the second base material is placed in the peripheral edge portion.

12. The thermal insulation material for a battery pack according to claim 11 , wherein the fixing member has elasticity.

13. A battery pack, comprising:
a plurality of battery cells that is lithium ion batteries; and
the thermal insulation material for a battery pack according to claim 1 that is placed between adjacent ones of the battery cells.

14. The thermal insulation material for a battery pack according to claim 9 , wherein
both of the first base material and the second base material are made of non-woven fabric, and
by fixing the first base material and the second base material in the peripheral edge portion, the thermal insulation layer can be housed in the bag-shaped space formed by the first base material and the second base material.

Assignees

• Sumitomo Riko Co Ltd
• Toyota Motor Co Ltd

Inventors

• Katayama Naoki
• Kumagai Shinji
• Hayashi Shota
• Taguchi Yutaro
• Shintaku Yuji

Classifications

• B32B2307/51

  Elastic · CPC title

• H01M50/204

  Racks, modules or packs for multiple batteries or multiple cells · CPC title

• H01M10/647

  Prismatic or flat cells, e.g. pouch cells · CPC title

• H01M10/0525

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

• Y02E60/10

  Energy storage using batteries · CPC title