Negative electrode material for non-aqueous electrolyte secondary battery and non-aqueous electrolyte secondary battery

Patent metadata

Field	Value
Publication number	US-10950852-B2
Application number	US-201816497629-A
Country	US
Kind code	B2
Filing date	Feb 16, 2018
Priority date	Mar 29, 2017
Publication date	Mar 16, 2021
Grant date	Mar 16, 2021

Abstract

A negative electrode material for a non-aqueous electrolyte secondary battery includes: a lithium silicate phase including lithium silicate particles; silicon particles dispersed in the lithium silicate phase; and a low-melting point inorganic oxide that has a lower melting point than lithium silicate forming the lithium silicate particles, and that is solid at room temperature. The lithium silicate particles and the silicon particles form a particle agglomerate, and the low-melting point inorganic oxide is filled in at least a portion of voids included in the particle agglomerate.

First claim

The invention claimed is:

1. A negative electrode material for a non-aqueous electrolyte secondary battery, comprising:
a lithium silicate phase including lithium silicate particles;
silicon particles dispersed in the lithium silicate phase; and
a low-melting point inorganic oxide that has a lower melting point than lithium silicate forming the lithium silicate particles, and that is solid at room temperature,
wherein the lithium silicate particles and the silicon particles form a particle agglomerate, and
the low-melting point inorganic oxide is filled in at least a portion of voids included in the particle agglomerate.

2. The negative electrode material for a non-aqueous electrolyte secondary battery according to claim 1 ,
wherein the low-melting point inorganic oxide is a glassy oxide.

3. The negative electrode material for a non-aqueous electrolyte secondary battery according to claim 1 ,
wherein the low-melting point inorganic oxide includes at least one element selected from the group consisting of B and P.

4. The negative electrode material for a non-aqueous electrolyte secondary battery according to claim 3 ,
wherein the low-melting point inorganic oxide includes at least B.

5. The negative electrode material for a non-aqueous electrolyte secondary battery according to claim 4 ,
wherein 50 mol % or more of the B included in the low-melting point inorganic oxide is B having a tetracoordinated structure.

6. The negative electrode material for a non-aqueous electrolyte secondary battery according to claim 1 ,
wherein the particle agglomerate is a secondary particle in which a plurality of primary particles including the lithium silicate phase and the silicon particles dispersed in the lithium silicate phase are agglomerated, and the low-melting point inorganic oxide is present in at least a portion of an interface between the adjacent primary particles.

7. A non-aqueous electrolyte secondary battery comprising:
a negative electrode including the negative electrode material for a non-aqueous electrolyte secondary battery according to claim 1 ; a positive electrode capable of electrochemically absorbing and desorbing lithium; and a non-aqueous electrolyte.

Assignees

• Panasonic Ip Man Co Ltd

Inventors

• HAYASHIDA Kazuro
• Katou Daisuke

Classifications

• H01M4/5825

  Oxygenated metallic salts or polyanionic structures, e.g. borates, phosphates, silicates, olivines · CPC title

• Y02E60/10

  Energy storage using batteries · CPC title

• H01M4/364 Primary

  as mixtures · CPC title

• H01M10/0525

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

• H01M2004/027

  Negative electrodes · CPC title