Slurry composition for non-aqueous secondary battery functional layer, separator for non-aqueous secondary battery, and non-aqueous secondary battery

Patent metadata

Field	Value
Publication number	US-12119514-B2
Application number	US-201917268479-A
Country	US
Kind code	B2
Filing date	Aug 21, 2019
Priority date	Aug 24, 2018
Publication date	Oct 15, 2024
Grant date	Oct 15, 2024

Abstract

Provided is a slurry composition for a functional layer that can form a functional layer capable of closely adhering strongly to a separator substrate and that can enhance rate characteristics of a secondary battery including a separator that includes the functional layer. The slurry composition for a functional layer contains a binder and a melamine compound. The binder is a polymer including at least one functional group selected from the group consisting of a carboxy group, a hydroxyl group, an amino group, an epoxy group, an oxazoline group, a sulfo group, a nitrile group, and an amide group. The melamine compound has a volume-average particle diameter of not less than 20 nm and not more than 300 nm and constitutes a proportion of not less than 0.5 mass % and not more than 85 mass % among the total of the binder and the melamine compound.

First claim

The invention claimed is:

1. A slurry composition for a non-aqueous secondary battery functional layer comprising a binder and a melamine compound, wherein
the binder is a polymer including at least one functional group selected from the group consisting of a carboxy group, a hydroxyl group, an amino group, an epoxy group, an oxazoline group, a sulfo group, a nitrile group, and an amide group,
the binder has a volume-average particle diameter of not less than 20 nm and not more than 300 nm,
the melamine compound has a volume-average particle diameter of not less than 20 nm and not more than 300 nm, where the volume-average particle diameter is measured by laser diffraction and determined as a particle diameter at which a cumulative undersize calculated from a small diameter end of a particle diameter distribution by volume measured by the later diffraction reaches 50%,
the melamine compound constitutes a proportion of not less than 0.5 mass % and not more than 85 mass % among a total of the binder and the melamine compound.

2. The slurry composition for a non-aqueous secondary battery functional layer according to claim 1 , further comprising non-conductive particles.

3. A separator for a non-aqueous secondary battery comprising: a separator substrate; and a functional layer on the separator substrate, wherein
the functional layer is a dried product of the slurry composition for a non-aqueous secondary battery functional layer according to claim 1 .

4. The separator for a non-aqueous secondary battery according to claim 3 , wherein a portion of the dried product encroaches into the separator substrate.

5. The separator for a non-aqueous secondary battery according to claim 3 , wherein the separator substrate is a microporous membrane containing either or both of a polyolefin resin and an aromatic polyamide resin or a non-woven fabric containing either or both of a polyolefin resin and an aromatic polyamide resin.

6. A non-aqueous secondary battery comprising a positive electrode, a negative electrode, a separator, and an electrolyte solution, wherein
the separator is the separator for a non-aqueous secondary battery according to claim 4 .

7. The slurry composition for a non-aqueous secondary battery functional layer according to claim 1 , wherein the polymer is at least one selected from the group consisting of
a polymer including a carboxy group and a hydroxyl group;
a polymer including a carboxy group and an amide group;
a polymer including a carboxy group, a nitrile group, and an amino group; and
a polymer including a carboxy group, an epoxy group, a hydroxyl group, and a nitrile group.

8. The slurry composition for a non-aqueous secondary battery functional layer according to claim 1 , wherein the polymer is at least one selected from the group consisting of
a polymer including a carboxy group-containing monomer unit and a hydroxyl group-containing monomer unit;
a polymer including a carboxy group-containing monomer unit and an amide group-containing monomer unit;
a polymer including a carboxy group-containing monomer unit, a nitrile group-containing monomer unit, and an amino group-containing monomer unit; and
a polymer including a carboxy group-containing monomer unit, an epoxy group-containing monomer unit, a hydroxyl group-containing monomer unit, and a nitrile group-containing monomer unit.

9. The slurry composition for a non-aqueous secondary battery functional layer according to claim 1 , further comprising a solvent, wherein the solvent is water.

Assignees

• Zeon Corp

Inventors

• Asai Kazuki
• Akita Yasuhiro
• Sonobe Kenya

Classifications

• H01M50/409

  Separators, membranes or diaphragms characterised by the material · CPC title

• H01M50/443

  Particulate material · CPC title

• H01M2300/0025

  Organic electrolyte · CPC title

• H01M10/0566

  Liquid materials · CPC title

• H01M10/0525

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