Lithium ion secondary battery including porous insulating layer formed on positive electrode and electrolyte solution having halogenated cyclic acid anhydride

Patent metadata

Field	Value
Publication number	US-11563237-B2
Application number	US-201816608008-A
Country	US
Kind code	B2
Filing date	Apr 24, 2018
Priority date	Apr 25, 2017
Publication date	Jan 24, 2023
Grant date	Jan 24, 2023

Abstract

A purpose of the present invention is to provide a lithium ion secondary battery in which an increase in internal resistance is suppressed and a halogenated cyclic anhydride is used as an electrolyte additive. The lithium ion secondary battery according to the present invention comprises a positive electrode and an electrolyte solution, wherein a porous layer comprising an insulating filler is formed on the positive electrode, and the electrolyte solution comprises 0.005 to 10 weight % of a halogenated cyclic acid anhydride.

First claim

The invention claimed is:

1. A lithium ion secondary battery, comprising:
a positive electrode comprising:
a positive electrode current collector,
a positive electrode active material layer formed on the positive electrode current collector, and
a porous layer comprising aluminum oxide and polyvinylidene fluoride (PVdF) formed on the positive electrode active material layer,

a negative electrode comprising graphite, and
an electrolyte solution,
wherein the porous layer comprising the aluminum oxide and the PVdF is formed by applying a coating material for forming the porous layer directly on the positive electrode,
the positive electrode active material layer comprises a positive electrode active material represented by the following formula (3):
LiNi 62 Co γ Mn δ O 2   (3),

wherein, in formula (3), 0.75≤β≤0.85, 0.05γ≤0.15, 0.10≤δ≤0.20, and β+γ+δ=1; and
the electrolyte solution comprises:
0.05 to 5 weight % of hexafluoroglutaric anhydride, and,
a non-aqueous solvent comprising ethylene carbonate (EC), diethyl carbonate (DEC), and ethyl methyl carbonate (EMC).

2. A vehicle equipped with the lithium ion secondary battery according to claim 1 .

3. A method for manufacturing a lithium ion secondary battery comprising a positive electrode, a separator, a negative electrode, and an electrolyte solution, the negative electrode comprising graphite, the positive electrode comprising a positive electrode current collector, a positive electrode active material layer, and a porous layer comprising aluminum oxide and polyvinylidene fluoride (PVdF) formed on the positive electrode active material layer, the method comprising the steps of:
fabricating an electrode element by stacking the positive electrode and the negative electrode via the separator, and
enclosing the electrode element and the electrolyte solution into an outer package,
wherein the electrolyte solution comprises 0.05 to 5 weight % of a hexafluoroglutaric anhydride, and a non-aqueous solvent comprising ethylene carbonate (EC), diethyl carbonate (DEC), and ethyl methyl carbonate (EMC),
the positive electrode active material layer comprises a positive electrode active material represented by the following formula (3):
LiNi 62 Co γ Mn δ O 2   (3),

wherein, in formula (3), 0.75≤β≤0.85, 0.05γ≤0.15, 0.10≤δ≤0.20, and β+γ+δ=1; and
the porous layer comprising the aluminum oxide and PVdF is formed by applying a coating material for forming the porous layer directly on the positive electrode.

Assignees

• Nec Corp

Inventors

• Otohata Makihiro
• Yoshida Noboru

Classifications

• H01M10/0525

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

• C07D305/10 Primary

  having one or more double bonds between ring members or between ring members and non-ring members · CPC title

• H01M10/0567 Primary

  characterised by the additives · CPC title

• H01M2300/0025

  Organic electrolyte · CPC title

• H01M10/058

  Construction or manufacture · CPC title