Electrode additives and coatings for minimizing cathode transition metal dissolution

Patent metadata

Field	Value
Publication number	US-11417888-B2
Application number	US-201916573605-A
Country	US
Kind code	B2
Filing date	Sep 17, 2019
Priority date	Sep 17, 2019
Publication date	Aug 16, 2022
Grant date	Aug 16, 2022

Abstract

An electrode including an electrode active material and a ceramic hydrofluoric acid (HF) scavenger is provided. The ceramic hydrofluoric acid (HF) scavenger includes M2SiO3, MAlO2, M2O—Al2O3—SiO2, or combinations thereof, where M is lithium (Li), sodium (Na), or combinations thereof. Methods of making the electrode are also provided.

First claim

What is claimed is:

1. A method of fabricating an electrode that scavenges hydrofluoric acid (HF), the method comprising:
mixing a ceramic hydrofluoric acid (HF) scavenger powder into a solution comprising a binder dissolved in a solvent to form a slurry having a viscosity of greater than or equal to about 5000 cps to less than or equal to about 6000 cps, the ceramic hydrofluoric acid (HF) scavenger powder comprising M 2 SiO 3 , MAlO 2 , M 2 O—Al 2 O 3 —SiO 2 , or combinations thereof, where M is lithium (Li), sodium (Na), or combinations thereof;
casting a continuous layer of the slurry onto a surface of an electrode active material layer;
removing the solvent from the slurry to form a coating on the electrode active material layer, wherein the coating has a first porosity and scavenges hydrofluoric acid (HF).

2. The method according to claim 1 , wherein the solution comprising the binder dissolved in the solvent comprises 6 wt. % polyvinylidene fluoride (PVDF) dissolved in N-Methyl-2-pyrrolidone (NMP).

3. The method according to claim 1 , wherein the continuous layer of the slurry has a thickness of greater than or equal to about 1 μm to less than or equal to about 20 μm.

4. The method according to claim 1 , wherein the slurry comprises the ceramic hydrofluoric acid (HF) scavenger powder at a concentration of greater than or equal to about 70 wt. % to less than or equal to about 95 wt. %.

5. The method according to claim 1 , further comprising:
calendaring the coating to generate a second porosity in the coating, the second porosity being lower than the first porosity.

6. A method of fabricating an electrode that scavenges hydrofluoric acid (HF), the method comprising:
mixing a powder of a ceramic hydrofluoric acid (HF) scavenger into a solution comprising a binder dissolved in a solvent to form a slurry having a viscosity of greater than or equal to about 200 cps and less than or equal to about 1000 cps, the ceramic hydrofluoric acid (HF) scavenger comprising M 2 SiO 3 , MAlO 2 , M 2 O—Al 2 O 3 —SiO 2 , or combinations thereof, where M is lithium (Li), sodium (Na), or combinations thereof;
mixing a cathode active material into the slurry until the slurry has a viscosity of greater than or equal to about 4000 cps to less than or equal to about 6000 cps;
casting a continuous layer of the slurry onto a current collector; and
removing the solvent from the slurry to generate the electrode that scavenges hydrofluoric acid (HF), the electrode having a first porosity,
wherein the electrode that scavenges hydrofluoric acid (HF) comprises the ceramic hydrofluoric acid (HF) scavenger embedded within the cathode active material.

7. The method according to claim 6 , wherein the solution comprising the binder dissolved in the solvent comprises 6 wt. % polyvinylidene fluoride (PVDF) dissolved in N-Methyl-2-pyrrolidone (NMP).

8. The method according to claim 6 , wherein the solution further comprises carbon black.

9. The method according to claim 6 , wherein the slurry comprises the cathode active material at a concentration of greater than or equal to about 70 wt. % to less than or equal to about 95 wt. %.

10. The method according to claim 6 , further comprising:
calendaring the electrode to generate a second porosity in the electrode, the second porosity being lower than the first porosity.

Assignees

• Gm Global Tech Operations Llc

Inventors

• Xiao Xingcheng
• Liu Jin
• Xu Jiagang
• Cai Mei
• Zeng Sherman H

Classifications

• H01M4/13 Primary

  Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof · CPC title

• H01M4/1399

  of electrodes based on electro-active polymers · CPC title

• H01M2004/028

  Positive electrodes · CPC title

• H01M4/623

  fluorinated polymers · CPC title

• H01M4/602

  Polymers · CPC title