Additive for iron-air batteries

Patent metadata

Field	Value
Publication number	US-2025140990-A1
Application number	US-202418926383-A
Country	US
Kind code	A1
Filing date	Oct 25, 2024
Priority date	Oct 27, 2023
Publication date	May 1, 2025
Grant date	—

Abstract

An alkaline electrolyte including: an alkaline solution having a total hydroxide concentration of greater than 1 molar, based on a total volume of the alkaline electrolyte; and an additive including a trivalent element, wherein a concentration of the trivalent element is 1 millimolar to 5 molar, based on a total volume of the alkaline electrolyte, sulfur, and tin.

First claim

What is claimed is:

1 . An alkaline electrolyte comprising:
an alkaline solution having a total hydroxide concentration of greater than 1 molar, based on a total volume of the alkaline electrolyte; and an additive comprising
a trivalent element, wherein a concentration of the trivalent element is 1 millimolar to 5 molar, based on a total volume of the alkaline electrolyte,
sulfur, and tin.

2 . The alkaline electrolyte of claim 1 , wherein the trivalent element is aluminum, scandium, yttrium, boron, or a combination thereof, optionally aluminum.

3 . The alkaline electrolyte of claim 2 , wherein the trivalent element is aluminum, optionally wherein the additive comprises an aluminate.

4 . The alkaline electrolyte of claim 3 , wherein the concentration of the trivalent element is 10 to 250 millimolar, based on the total volume of the alkaline electrolyte.

5 . The alkaline electrolyte of claim 3 , wherein the concentration of the trivalent element is 1 to 5 molar, based on the total volume of the alkaline electrolyte.

6 . The alkaline electrolyte of claim 5 ,
wherein the trivalent element is aluminum, and wherein a concentration of the aluminum is 1 to 5 molar, based on a total volume of the alkaline electrolyte.

7 . The alkaline electrolyte of claim 3 , wherein the additive comprises a sulfide, optionally zinc sulfide.

8 . The alkaline electrolyte of claim 7 , wherein the sulfur is a reduction product or a dissociation product of the additive comprising the sulfide.

9 . The alkaline electrolyte of claim 1 , wherein a concentration of the sulfur is 0.01 to 500 millimolar, based on the total volume of the alkaline electrolyte.

10 . The alkaline electrolyte of claim 1 , wherein the tin is stannate.

11 . The alkaline electrolyte of claim 1 , wherein a concentration of the tin is greater than 30 millimolar, based on the total volume of the alkaline electrolyte.

12 . The alkaline electrolyte of claim 1 , wherein the additive comprises a single additive that comprises the trivalent element and the sulfur.

13 . The alkaline electrolyte of claim 1 , wherein the additive comprises a single additive that comprises the trivalent element and the tin.

14 . The alkaline electrolyte of claim 1 , wherein the additive comprises a single additive that comprises the trivalent element, the sulfur, and the tin.

15 . The alkaline electrolyte of claim 1 , wherein the additive comprises a first additive comprising the trivalent element and a second additive comprising the sulfur.

16 . The alkaline electrolyte of claim 15 , further comprising a third additive comprising the tin.

17 . The alkaline electrolyte of claim 1 , wherein the additive comprises a first additive comprising the trivalent element and a second additive comprising the tin.

18 . The alkaline electrolyte of claim 17 , further comprising a third additive comprising the sulfur.

19 . The alkaline electrolyte of claim 1 , wherein the alkaline electrolyte has a total hydroxide concentration of 4 to 8 molar, based on the total volume of the alkaline electrolyte.

20 . The alkaline electrolyte of claim 1 , wherein the alkaline electrolyte comprises an alkali metal hydroxide, and the alkaline electrolyte is in a form of a liquid, a gel, or combination thereof.

21 . The alkaline electrolyte of claim 1 , wherein the additive further comprises iron having an oxidation state of 0, 2, 3, or a combination thereof.

22 . An alkaline electrolyte comprising:
an alkaline solution having a total hydroxide concentration of greater than 1 molar, based on a total volume of the alkaline electrolyte; a trivalent element, wherein a concentration of the trivalent element is 10 to 250 millimolar, or 1 to 5 molar, based on a total volume of the alkaline electrolyte; tin; and sulfur, wherein a concentration of the sulfur is 0.01 to 500 millimolar, based on the total volume of the alkaline electrolyte.

23 . The alkaline electrolyte of claim 22 , wherein the trivalent element is aluminum, optionally wherein the alkaline electrolyte comprises an aluminate.

24 . The alkaline electrolyte of claim 22 , wherein the alkaline electrolyte comprises a sulfide.

25 . The alkaline electrolyte of claim 22 , wherein the concentration of the sulfur is 0.01 to 500 millimolar, based on the total volume of the alkaline electrolyte.

26 . The alkaline electrolyte of claim 22 , wherein the tin is a stannate.

27 . The alkaline electrolyte of claim 22 , wherein a concentration of the tin is greater than 30 millimolar, based on the total volume of the alkaline electrolyte.

28 . The alkaline electrolyte of claim 22 , wherein the alkaline electrolyte comprises a single additive that comprises
the trivalent element and the sulfur,
the trivalent element and the tin, or
the trivalent element, the sulfur, and the tin.

29 . The alkaline electrolyte of claim 22 , wherein the alkaline electrolyte comprises a mixture of a first additive comprising the trivalent element and a second additive comprising the sulfur, optionally wherein the mixture further comprises a third additive comprising the tin.

30 . The alkaline electrolyte of claim 22 , wherein the additive comprises a mixture of a first additive comprising the trivalent element and a second additive comprising the tin, optionally wherein the mixture further comprises a third additive comprising the sulfur.

31 . The alkaline electrolyte of claim 22 , wherein the alkaline electrolyte has a total hydroxide concentration of 4 to 8 molar, based on the total volume of the alkaline electrolyte, optionally wherein the alkaline electrolyte comprises an alkali metal hydroxide, and the alkaline electrolyte is in a form of a liquid, a gel, or a combination thereof.

32 . The alkaline electrolyte of claim 22 , wherein the additive further comprises iron having an oxidation state of 0, 2, 3, or a combination thereof.

33 . An alkaline electrolyte for an iron-air battery, the electrolyte comprising:
an alkaline solution having a total hydroxide concentration of greater than 1 molar, based on a total volume of the alkaline electrolyte; aluminum, wherein a concentration of the aluminum is 10 millimolar to 250 millimolar, or 1 to 5 molar, based on the total volume of the alkaline electrolyte; sulfur, wherein a concentration of the sulfur is 0.01 millimolar to 500 millimolar, based on the total volume of the alkaline electrolyte; and tin, wherein a concentration of the tin is 30 millimolar to 500 millimolar, based on the total volume of the alkaline electrolyte.

34 . The alkaline electrolyte of claim 33 , wherein the alkaline electrolyte comprises a single additive comprising the aluminum, the sulfur, and the tin, wherein the additive has a concentration of 10 to 250 millimolar or 1 to 5 molar, based on the total volume of the alkaline electrolyte.

35 . An electrode for an electrochemical cell, the electrode comprising:
iron; and an additive comprising a trivalent element, wherein a content of the additive is greater than 0.01 wt %, based on a total weight of the iron in the electrode.

36 . The electrode of claim 35 , wherein the trivalent element is aluminum, scandium, yttrium, boron, or a c

Assignees

• Form Energy Inc

Inventors

• Bentley Caitlin
• Taylor Olivia
• Thompson Annelise
• Norman Zachariah
• Kyriakides Cleo
• Gray Sydney
• Schroder Kjell William
• Gibson Michael
• Taussig Abigail

Classifications

• H01M12/06

  with one metallic and one gaseous electrode · CPC title

• H01M10/26

  Selection of materials as electrolytes · CPC title

• H01M4/62

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

• H01M12/08 Primary

  composed of a half-cell of a fuel-cell type and a half-cell of the secondary-cell type · CPC title

• H01M2300/0014

  Alkaline electrolytes · CPC title