Adhesive sheet for sealing metal terminals of flat electrochemical cell

Patent metadata

Field	Value
Publication number	US-10144202-B2
Application number	US-85832807-A
Country	US
Kind code	B2
Filing date	Sep 20, 2007
Priority date	Sep 21, 2006
Publication date	Dec 4, 2018
Grant date	Dec 4, 2018

Abstract

In a packaging body provided with at least an inner layer composed of a thermal-adhesive polyolefin based resin and a barrier layer composed of a metal foil, in which metal terminals are sealed by the thermal-adhesive resin with unconnected ends of the metal terminals protruding outside, an adhesive sheet for sealing metal terminals of a flat electrochemical cell which is not only able to prevent a short circuit between the barrier layer and the metal terminals but high in a layer-to-layer adhesive strength and a low possibility of a reduction in battery performance to be caused due to invasion of moisture is provided. In the adhesive sheet for sealing a metal terminal part of a flat electrochemical cell according to the invention, a fibrous sheet or a porous sheet is covered by the inner layer and an acid-modified polyolefin based resin layer having adhesive properties.

First claim

What is claimed is:

1. An electrochemical cell comprising:
a packaging material provided with, at least, an inner layer formed of a polypropylene thermal-adhesive resin and a barrier layer formed of a metal foil;
an electrochemical device including a positive electrode, a negative electrode, and metal terminals connected to the positive and negative electrodes respectively; and
an adhesive sheet comprising a fibrous sheet with both surfaces thereof coated with acid-modified polypropylene resin,
wherein
the electrochemical device is enclosed in the packaging material,
the fibrous sheet is non-woven fabric having a basis weight of from 5 to 25 g/m 2 and a density of from 0.15 to 0.45 g/cm 3 ,
one of the surfaces of the adhesive sheet is in contact with the metal terminals, and
the other of the surfaces of the adhesive sheet is in contact with the inner layer.

2. The electrochemical cell according to claim 1 , wherein the fibrous sheet is a natural fiber or a chemical fiber made of a synthetic resin having a melting point of 200° C. or higher.

3. The electrochemical cell according to claim 2 , wherein the fibrous sheet is composed mainly of a wholly aromatic polyester based fiber.

4. The electrochemical cell according to claim 3 , wherein the wholly aromatic polyester based fiber is a melt-anisotropic wholly aromatic polyester fiber.

5. The electrochemical cell according to claim 3 , wherein the fibrous sheet is composed of the wholly aromatic polyester based fiber having a moisture absorption rate of not more than 0.1% under an environment at 25° C. and 65% RH.

6. The electrochemical cell according to claim 4 , wherein the fibrous sheet is composed of the wholly aromatic polyester based fiber having a moisture absorption rate of not more than 0.1% under an environment at 25° C. and 65% RH.

Assignees

• Mochizuki Youichi
• Okushita Masataka
• Akita Hiroshisa
• Nishida Sumito
• Dainippon Printing Co Ltd

Inventors

• Mochizuki Youichi
• Okushita Masataka
• Akita Hiroshisa
• Nishida Sumito

Classifications

• H01M50/178

  for pouch or flexible bag cells · CPC title

• H01M50/553

  Terminals adapted for prismatic, pouch or rectangular cells · CPC title

• H01M50/55

  on the same side of the cell · CPC title

• H01M50/567

  by fixing means, e.g. screws, rivets or bolts · CPC title

• H01M50/562

  characterised by the material · CPC title