Solid state additives for iron negative electrodes

Patent metadata

Field	Value
Publication number	US-2024243246-A1
Application number	US-202318479668-A
Country	US
Kind code	A1
Filing date	Oct 2, 2023
Priority date	Aug 17, 2022
Publication date	Jul 18, 2024
Grant date	—

Abstract

According to one aspect, an additive for an iron negative electrode of an alkaline electrochemical cell may include a powder of discrete granules including agglomerated particles, the agglomerated particles including at least one metal sulfide.

First claim

What is claimed is:

1 . A method for making an electrode for a battery, comprising:
forming an electrode structure comprising an iron active material and a source of zinc; and converting the source of zinc to zinc-sulfide on or in the electrode structure through a sulfidation reaction.

2 . The method of claim 1 , wherein the source of zinc comprises a zinc oxide powder.

3 . A method of making an electrode for a battery, comprising:
contacting an electrode structure comprising an iron active material with a solution comprising dissolved zinc; and exposing the solution contacted structure to a sulfide source to convert at least a portion of the dissolved zinc to zinc sulfide.

4 . The method of claim 3 , wherein the sulfide source is a solution comprising Na 2 S.

5 . The method of claim 3 , wherein the sulfide source is a gas comprising H 2 S.

6 . The method of claim 3 , wherein the solution comprising dissolved zinc comprises a solvent and a gelling agent.

7 . The method of claim 3 , further comprising drying the exposed solution contacted structure, wherein the drying occurs at one or more temperatures at or below 800 degrees Celsius.

8 . The method of claim 7 , wherein the drying occurs in a furnace.

9 . A method of making an electrode for a battery, comprising:
forming a sulfidation solution comprised of a solvent and a sulfide source; forming an electrode structure comprising an iron active material and a solid zinc source; contacting the electrode structure with the sulfidation solution; and maintaining the sulfidation solution in contact with the electrode structure for a period of time such that zinc sulfide is incorporated on or in the electrode structure.

10 . The method of claim 9 , wherein:
the sulfidation solution is a component of an electrolyte solution; and contacting the electrode structure with the sulfidation solution comprises adding the sulfidation solution to a battery cell including the electrode structure such that the sulfidation solution contacts the electrode structure.

11 . The method of claim 9 , wherein the solvent comprises KOH and the sulfide source comprises Na 2 S.

12 . The method of claim 9 , wherein the solid zinc source is formed from solid zinc oxide particles or agglomerated particles of zinc oxide.

13 . The method of claim 12 , wherein a molar ratio of Na 2 S in the sulfidation solution to zinc oxide in the electrode structure is between 1 and 2.

14 . The method of claim 13 , wherein the period of time is less than 168 hours.

15 . A method of making an electrode for a battery, comprising:
forming a structure comprising an iron active material and a solid source of zinc by one or more processes performed at or above a first processing temperature; and exposing the formed structure to a sulfide source gas while maintaining a selected concentration of the sulfide source gas.

16 . The method of claim 15 , wherein the one or more processes performed at or above the first processing temperature comprise one or more of sintering and hot pressing.

17 . The method of claim 15 , wherein exposing the formed structure to the sulfide source gas while maintaining the selected concentration of the sulfide source gas comprises exposing the formed structure to the sulfide source gas while maintaining the selected concentration of the sulfide source gas and a second processing temperature that is below the first processing temperature such that a sulfidation reaction of the zinc oxide occurs to form zinc sulfide.

18 . The method of claim 17 , wherein the first processing temperature is at or above 800 degrees Celsius and the second processing temperature is at or below 600 degrees Celsius.

19 . The method of claim 17 , wherein the second processing temperature is at or below 400 degrees Celsius.

20 . The method of claim 15 , wherein the sulfide source gas is H 2 S and the selected concentration of the sulfide source gas is between 0.25% and 1%.

21 . The method of claim 15 , wherein the exposing the formed structure to the sulfide source gas occurs as part of a cooling phase of a last of the one or more processes used to form the formed structure.

22 . The method of claim 15 , wherein the zinc oxide is formed from solid zinc oxide particles or agglomerated particles of zinc oxide.

Assignees

• Form Energy Inc

Inventors

• Hooke David
• Gibson Michael Andrew
• Thompson Annelise Christine
• Pantano Joseph Anthony
• Syvertsen Marc Louis

Classifications

• H01M4/0471 Primary

  involving thermal treatment, e.g. firing, sintering, backing particulate active material, thermal decomposition, pyrolysis · CPC title

• H01M4/38

  of elements or alloys · CPC title

• H01M2004/027

  Negative electrodes · CPC title

• H01M4/62 Primary

  Selection of inactive substances as ingredients for active masses, e.g. binders, fillers · CPC title

• Y02E60/10

  Energy storage using batteries · CPC title