Cellulose-based self-standing films for use in li-ion batteries

Patent metadata

Field	Value
Publication number	US-2024063400-A1
Application number	US-202318491279-A
Country	US
Kind code	A1
Filing date	Oct 20, 2023
Priority date	May 15, 2018
Publication date	Feb 22, 2024
Grant date	—

Abstract

The present technology relates to self-standing electrodes, their use in electrochemical cells, and their production processes using a water-based filtration process. For example, the self-standing electrodes may be used in lithium-ion batteries (LIBs). Particularly, the self-standing electrodes comprise a first electronically conductive material serving as a current collector, the surface of the first electronically conductive material being grafted with a hydrophilic group, a binder comprising cellulose fibres, an electrochemically active material, and optionally a second electronically conductive material. A process for the preparation of the self-standing electrodes is also described.

First claim

What is claimed is:

1 . An electrode material comprising an electrochemically active material in the form of particles coated with a carbon layer in a core-shell configuration, wherein the surface of the carbon layer is grafted with at least one aryl group of Formula I:

wherein:
FG is a hydrophilic functional group selected from a carboxylic acid and a sulfonic acid functional group; and
n is an integer in the range of 1 to 5.

2 . The electrode material of claim 1 , wherein n is in the range of 1 to 3.

3 . The electrode material of claim 2 , wherein n is 1 or 2.

4 . The electrode material of claim 3 , wherein n is 1.

5 . The electrode material of claim 1 , wherein the particles are selected from metal oxide particles, lithiated metal oxide particles, metal phosphate particles, lithiated metal phosphate particles, carbon-based particles, and a combination of at least two thereof.

6 . The electrode material of claim 5 , wherein the metal is a transition metal selected from titanium (Ti), iron (Fe), manganese (Mn), vanadium (V), nickel (Ni), cobalt (Co), and a combination of at least two thereof.

7 . The electrode material of claim 5 , wherein the particles comprise lithiated iron phosphate (LiFePO 4 ) particles.

8 . The electrode material of claim 5 , wherein the particles comprise lithium titanate (Li 4 Ti 5 O 12 ) particles.

9 . The electrode material of claim 1 , further comprising an electronically conductive material selected from carbon black, acetylene black, graphite, graphene, carbon fibers, carbon nanofibers, carbon nanotubes, and a combination of at least two thereof.

10 . The electrode material of claim 9 , wherein the electronically conductive material comprises carbon fibers.

11 . The electrode material of claim 10 , wherein the carbon fibers are vapor grown carbon fibers (VGCFs).

12 . The electrode material of claim 1 , further comprising a binder comprising cellulose fibers.

13 . A process for the manufacturing of an electrode material as defined in claim 1 , the process comprising the following steps:
providing an electrochemically active material in the form of particles coated with a carbon layer in a core-shell configuration; and grafting at least one aryl group of Formula I on the surface of the carbon layer.

14 . The process of claim 13 , wherein the grafting step of the process comprises:
(i) generating an aryl diazonium ion by contacting an aniline of Formula II:

 wherein:
FG and n are as defined in claim 1 , with a diazotizing agent; and

(ii) reacting the aryl diazonium ion generated in step (i) with the carbon of the carbon layer of the electrochemically active material.

15 . The process of claim 14 , wherein the diazotizing agent is present in a range of from 0.01 to 0.04 equivalent with respect to the carbon, or of about 0.03 equivalent with respect to the carbon.

16 . The process of claim 14 , wherein the diazotizing agent is present in a range of from 1 to 4 equivalents with respect to the aniline of Formula II, or of about 3 equivalents with respect to the aniline of Formula II.

17 . The process of claim 14 , wherein the diazotizing agent is a nitrite salt or an alkyl nitrite.

18 . The process of claim 14 , wherein the grafting step is carried out in an acidic aqueous medium or in a polar aprotic solvent.

19 . The process of claim 14 , wherein the aryl diazonium ion is generated in situ such that steps (i) and (ii) are performed simultaneously.

20 . An electrode comprising an electrode material as defined in claim 1 .

21 . An electrochemical cell comprising a negative electrode, a positive electrode, and an electrolyte, wherein at least one of the negative and positive electrodes comprises an electrode material as defined in claim 1 .

22 . The electrochemical cell of claim 21 , wherein the electrolyte is a liquid electrolyte comprising a lithium salt in a solvent, a gel electrolyte comprising a lithium salt in a solvent and/or a solvating polymer, or a solid polymer electrolyte comprising a lithium salt in a solvating polymer.

23 . A battery comprising at least one electrochemical cell as defined in claim 21 .

Assignees

• Hydro Quebec

Inventors

• Delaporte Nicolas
• Guerfi Abdelbast
• Zaghib Karim

Classifications

• H01M4/806 Primary

  Nonwoven fibrous fabric containing only fibres · CPC title

• H01M4/131 Primary

  Electrodes based on mixed oxides or hydroxides, or on mixtures of oxides or hydroxides, e.g. LiCoOx · CPC title

• H01M4/136

  Electrodes based on inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy · CPC title

• H01M4/1391

  of electrodes based on mixed oxides or hydroxides, or on mixtures of oxides or hydroxides, e.g. LiCoOx · CPC title

• H01M4/1397

  of electrodes based on inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy · CPC title