Carbon coating of alkaline cathode materials

Patent metadata

Field	Value
Publication number	US-11532809-B2
Application number	US-201916718544-A
Country	US
Kind code	B2
Filing date	Dec 18, 2019
Priority date	Dec 19, 2018
Publication date	Dec 20, 2022
Grant date	Dec 20, 2022

Abstract

Cathodes are provided, wherein at least one of the cathode's active material, binder, or graphite are in the form of carbon-coated particles. Alternatively, rings of the cathode, or the cathode itself, may be coated with carbon. The coating may be as thin as a single layer of carbon. Electrochemical cells comprising such cathodes are also provided. Methods of preparing such cathodes and electrochemical cells are also provided.

First claim

What is claimed is:

1. An electrode for an electrochemical cell, said electrode comprising electrode components, said electrode components comprising i) an active material, wherein the active material is an oxide, ii) a binder, and iii) graphite, wherein at least one of the electrode components is in the form of particles comprising a carbon coating, wherein the carbon coating has a thickness of about 0.3 nm-0.8 nm.

2. The electrode of claim 1 , wherein the active material is in the form of the particles comprising a carbon coating.

3. The electrode of claim 1 , wherein the binder is in the form of the particles comprising a carbon coating.

4. The electrode of claim 1 , wherein the graphite is in the form of the particles comprising a carbon coating.

5. The electrode of claim 1 , wherein the active material comprises at least one of manganese dioxide, a nickelate, nickel oxyhydroxide, or copper oxide.

6. The electrode of claim 5 , wherein the active material comprises at least one of electrolytic manganese dioxide (EMD), chemical manganese dioxide (CMD), or natural manganese dioxide (NMD).

7. The electrode of claim 1 , wherein the graphite is expanded graphite.

8. The electrode of claim 1 , wherein the binder comprises a material selected from the group consisting of polyvinylidene fluoride (PVDF), polyethylene, copolymers based on polystyrene and ethylene/propylene, polytetrafluoroethene (PTFE), poly(3,4-ethylenedioxythiophene) (PEDOT) copolymers, polystyrene sulfonate (PSS), and PEDOT:PSS polymer mixtures.

9. The electrode of claim 1 , wherein the carbon coating is one layer of carbon thick.

10. The electrode of claim 1 , wherein the electrode's conductivity is greater than that of an otherwise substantially identical electrode which does not comprise the carbon coating.

11. The electrode of claim 1 , wherein the electrode is a cathode.

12. An alkaline electrochemical cell, comprising the electrode of claim 1 .

13. The alkaline electrochemical cell of claim 12 , comprising an anode having an active material selected from the group consisting of zinc, magnesium, aluminum and silicon.

14. An electrode for an electrochemical cell, wherein the electrode is a ring-molded electrode comprising a plurality of rings, and wherein at least one of the rings has a carbon coating.

15. A method of producing the electrode of claim 1 , comprising
i) mixing active material, binder, and graphite, wherein at least one of these is in the form of particles having a carbon coating, with electrolyte and, optionally, additives, so as to make an electrode mix; and
ii) forming a plurality of rings from the electrode mix; and
iii) inserting the rings into a container.

16. A method of producing the electrode of claim 1 , comprising
i) mixing active material, binder, and graphite, wherein at least one of these is in the form of particles having a carbon coating, with electrolyte and, optionally, additives, so as to make an electrode mix; and
ii) using a ram to mold the electrode mix into a solid tubular configuration.

17. The method of claim 15 , wherein the electrode is a cathode.

18. The method of claim 15 , wherein the particles having a carbon coating are prepared by a method selected from the group consisting of chemical vapor deposition, carbon evaporation, laser ablation, and arc discharge.

Assignees

• Energizer Brands Llc

Inventors

• Slezak Philip J

Classifications

• H01M4/525

  of mixed oxides or hydroxides containing iron, cobalt or nickel for inserting or intercalating light metals, e.g. LiNiO2, LiCoO2 or LiCoOxFy · CPC title

• H01M4/1393 Primary

  of electrodes based on carbonaceous material, e.g. graphite-intercalation compounds or CFx · CPC title

• Y02E60/10

  Energy storage using batteries · CPC title

• H01M4/505

  of mixed oxides or hydroxides containing manganese for inserting or intercalating light metals, e.g. LiMn2O4 or LiMn2OxFy · CPC title

• H01M2004/021

  Physical characteristics, e.g. porosity, surface area · CPC title