Pressure sensitive adhesive sheet for batteries and lithium-ion battery

Patent metadata

Field	Value
Publication number	US-12119440-B2
Application number	US-202017130694-A
Country	US
Kind code	B2
Filing date	Dec 22, 2020
Priority date	Dec 26, 2019
Publication date	Oct 15, 2024
Grant date	Oct 15, 2024

Abstract

A pressure sensitive adhesive sheet for batteries, which includes a base material and a pressure sensitive adhesive layer provided on one surface side of the base material. The pressure sensitive adhesive layer contains inorganic fine particles having a water content of 0.4% or less in a single body.

First claim

The invention claimed is:

1. A lithium-ion battery, comprising:
two or more conductors fixed in a state of being in contact with each other inside the battery using a pressure sensitive adhesive sheet that comprises:
a base material; and
a pressure sensitive adhesive layer provided on one surface side of the base material,
the pressure sensitive adhesive layer containing inorganic fine particles having a water content of 0.4% or less in a single body, the inorganic fine particles being sulfate fine particles,
the pressure sensitive adhesive layer being formed of a pressure sensitive adhesive composition that consists of:
a (meth)acrylic ester polymer (A) that is a polymer obtained by solution polymerization, the (meth)acrylic ester polymer (A) having a weight-average molecular weight of 500,000 or more and 2,500,000 or less,
a crosslinker (B),
the inorganic fine particles, and
at least one additive selected from a tackifier, an antioxidant, a softening agent, and a filler.

2. The lithium-ion battery according to claim 1 , wherein the sulfate fine particles are barium sulfate fine particles.

3. The lithium-ion battery according to claim 1 , wherein a content of the inorganic fine particles in the pressure sensitive adhesive layer is 5 mass parts or more and 500 mass parts or less with respect to 100 mass parts of a pressure sensitive adhesive component contained in the pressure sensitive adhesive layer.

4. The lithium-ion battery according to claim 1 , wherein an average particle diameter of the inorganic fine particles is 0.01 μm or more and 10 μm or less.

5. The lithium-ion battery according to claim 1 , wherein the (meth)acrylic ester polymer (A) has a weight-average molecular weight of 750,000 or more and 2,500,000 or less.

6. The lithium-ion battery according to claim 1 , wherein an amount of gas generated by heating 1 g of the inorganic fine particles is 0.1 ml/g or more and 30 ml/g or less, the gas being generated from the pressure sensitive adhesive layer of the pressure sensitive adhesive layer, the amount of gas being obtained by heating an aluminum laminated bag containing the pressure sensitive adhesive layer and a prepared liquid, and then dividing the increase in volume of the aluminum laminated bag resulting from such heating by the mass of the inorganic fine particles contained in the pressure sensitive adhesive layer, the prepared liquid being obtained by dissolving lithium hexafluorophosphate (LiPF 6 ) at a concentration of 1 mol/L in a mixed liquid in which ethylene carbonate and diethyl carbonate are mixed at a volume ratio of 1:1.

Assignees

• Lintec Corp
• Panasonic Corp
• Panasonic Holdings Corp

Inventors

• Ansai Takeshi
• Kurata Yuichi
• Nishino Hajime
• Shiozaki Tomoki
• Yoshii Kazuhiro

Classifications

• C08K5/005

  Stabilisers against oxidation, heat, light, ozone · CPC title

• C08K5/0025

  Crosslinking or vulcanising agents; including accelerators · CPC title

• C09J2301/302

  the adhesive being pressure-sensitive, i.e. tacky at temperatures inferior to 30°C · CPC title

• C08K2201/003

  Additives being defined by their diameter · CPC title

• C09J2203/33

  for batteries or fuel cells · CPC title