Electrolyte for metal-air batteries, and metal-air battery

Patent metadata

Field	Value
Publication number	US-2017018828-A1
Application number	US-201615195423-A
Country	US
Kind code	A1
Filing date	Jun 28, 2016
Priority date	Jul 13, 2015
Publication date	Jan 19, 2017
Grant date	—

Abstract

An electrolyte for metal-air batteries, which is able to inhibit the coarsening of a discharge product that is produced upon the discharge of metal-air batteries, and a metal-air battery using the electrolyte. The electrolyte may comprise an aqueous solution that contains an inhibitor of the coarsening of a discharge product, the inhibitor containing a salt that contains at least one kind of anions selected from the group consisting of S 2− anions, SCN − anions and S 2 O 3 2− anions.

First claim

1 . An electrolyte for metal-air batteries having an anode containing at least one of aluminum and magnesium, the electrolyte comprising an aqueous solution comprising a coarsening inhibitor configured to inhibit coarsening of a discharge product, the coarsening inhibitor including a salt having at least one kind of anions selected from the group consisting of S 2− anions, SCN − anions and S 2 O 3 2− anions.

2 . The electrolyte according to claim 1 , wherein the coarsening inhibitor is at least one selected from the group consisting of Na 2 S, NaSCN and Na 2 S 2 O 3 .

3 . The electrolyte according to claim 1 , wherein a concentration of the coarsening inhibitor in the aqueous solution is in a range of 0.001 mol/L or more to 0.1 mol/L or less.

4 . The electrolyte according to claim 1 , wherein the aqueous solution is basic.

5 . The electrolyte according to claim 1 , wherein the aqueous solution includes an electrolyte salt.

6 . The electrolyte according to claim 5 , wherein the electrolyte salt is NaOH.

7 . The electrolyte according to claim 5 , wherein a concentration of the electrolyte salt in the aqueous solution is in a range of 0.01 mol/L or more to 20 mol/L or less.

8 . A metal-air battery comprising:
an air electrode configured to receive an oxygen supply; an anode containing at least one of aluminum and magnesium; and an electrolyte according to claim 1 , the electrolyte being in contact with the air electrode and the anode.

9 . The metal-air battery according to claim 8 , further comprising a separator disposed between the air electrode and the anode, the separator configured to retain the electrolyte.

10 . The metal-air battery according to claim 9 , wherein the separator is porous.

11 . The metal-air battery according to claim 10 , wherein the porosity of the separator is in a range of 30% to 90%.

12 . The metal-air battery according to claim 9 , wherein a thickness of the separator is in a range of 0.1 to 100 μm.

13 . The metal-air battery according to claim 8 , wherein a thickness of the air electrode is in a range of 2 μm to 500 μm.

14 . The metal-air battery according to claim 8 , wherein the aluminum is an aluminum metal containing impurities, and an element ratio of the aluminum in the aluminum metal is in a range of 50% or more to 99.99% or less.

15 . The metal-air battery according to claim 8 , wherein the aluminum is an aluminum alloy, and a content of the aluminum in the aluminum alloy is 50% by mass or more.

16 . The metal-air battery according to claim 8 , wherein the coarsening inhibitor is at least one selected from the group consisting of Na 2 S, NaSCN and Na 2 S 2 O 3 .

17 . The metal-air battery according to claim 8 , wherein a concentration of the coarsening inhibitor in the aqueous solution is in a range of 0.001 mol/L or more to 0.1 mol/L or less.

18 . The metal-air battery according to claim 8 , wherein the aqueous solution is basic.

19 . The metal-air battery according to claim 8 , wherein the aqueous solution includes an electrolyte salt.

Assignees

• Toyota Motor Co Ltd

Inventors

• Suyama Hiroshi

Classifications

• H01M50/491

  Porosity · CPC title

• H01M50/489

  Separators, membranes, diaphragms or spacing elements inside the cells, characterised by their physical properties, e.g. swelling degree, hydrophilicity or shut down properties · CPC title

• H01M4/38

  of elements or alloys · 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

• H01M2300/0002

  Aqueous electrolytes · CPC title