Negative electrode mixture, negative electrode and secondary battery

Patent metadata

Field	Value
Publication number	US-2024372094-A1
Application number	US-202418774090-A
Country	US
Kind code	A1
Filing date	Jul 16, 2024
Priority date	Jan 17, 2022
Publication date	Nov 7, 2024
Grant date	—

Abstract

Provided is a negative electrode mixture containing a single-walled carbon nanotube, a negative electrode active material, and a binder, in which the negative electrode mixture contains, as the negative electrode active material, a negative electrode active material that exhibits a potential of 2.5 V or less vs. Li when alloyed with Li or bonded with Li, and the binder contains a fluorine-containing copolymer containing vinylidene fluoride unit and a unit of an other monomer other than vinylidene fluoride.

First claim

1 . A negative electrode mixture, comprising a single-walled carbon nanotube, a negative electrode active material, and a binder, wherein
the negative electrode mixture comprises, as the negative electrode active material, a negative electrode active material that exhibits a potential of 2.5 V or less vs. Li when alloyed with Li or bonded with Li, and the binder contains a fluorine-containing copolymer containing vinylidene fluoride unit and a unit of an other monomer other than vinylidene fluoride.

2 . The negative electrode mixture according to claim 1 , wherein the negative electrode active material is a compound containing at least one element selected from the group consisting of Si, Sn, V, Nb, and Ti.

3 . The negative electrode mixture according to claim 1 , wherein the negative electrode active material is at least one selected from the group consisting of Si and SiO x , wherein 0<x<2.

4 . The negative electrode mixture according to claim 1 , wherein the negative electrode active material is a carbonaceous material.

5 . The negative electrode mixture according to claim 1 , wherein the negative electrode active material comprises a compound containing at least one element selected from the group consisting of Si, Sn, V, Nb, and Ti, and a carbonaceous material.

6 . The negative electrode mixture according to claim 1 , wherein an average outer diameter of the single-walled carbon nanotube is 2.5 nm or less.

7 . The negative electrode mixture according to claim 1 , wherein an average G/D ratio of the single-walled carbon nanotube is 2 or more.

8 . The negative electrode mixture according to claim 1 , wherein a content of the single-walled carbon nanotube is 0.001 to 10% by mass, based on a solid content mass of the negative electrode mixture.

9 . The negative electrode mixture according to claim 1 , wherein the other monomer is a fluorinated monomer, excluding vinylidene fluoride unit.

10 . The negative electrode mixture according to claim 1 , wherein the other monomer is at least one selected from the group consisting of tetrafluoroethylene, chlorotrifluoroethylene, (meth)acrylic acid, 2,3,3,3-tetrafluoropropene, hexafluoropropylene, and a fluoroalkyl vinyl ether.

11 . The negative electrode mixture according to claim 1 , wherein the binder further contains a polyvinylidene fluoride.

12 . The negative electrode mixture according to claim 11 , wherein a mass ratio of the polyvinylidene fluoride to the fluorine-containing copolymer, polyvinylidene fluoride/fluorine-containing copolymer, is 99/1 to 1/99.

13 . The negative electrode mixture according to claim 1 , further comprising a solvent.

14 . A negative electrode comprising a current collector and a negative electrode material layer provided on one side or each of both sides of the current collector and formed from the negative electrode mixture according to claim 1 .

15 . A secondary battery comprising the negative electrode according to claim 14 .

Assignees

• Daikin Ind Ltd
• Mcd Tech S A R L

Inventors

• Shimooka Toshiharu
• Hosoda Chihiro
• Ichinose Yuma
• Yamazaki Shigeaki
• Terada Junpei
• Sugitani Maho
• Predtechenskiy Mikhail Rudolfovich
• Bobrenok Oleg Filippovich

Classifications

• H01M4/485

  of mixed oxides or hydroxides for inserting or intercalating light metals, e.g. LiTi2O4 or LiTi2OxFy (H01M4/505, H01M4/525 take precedence) · CPC title

• H01M10/052

  Li-accumulators · CPC title

• H01M4/36

  Selection of substances as active materials, active masses, active liquids · CPC title

• H01M4/362

  Composites · CPC title

• H01M4/483

  for non-aqueous cells (H01M4/485 takes precedence) · CPC title