Metal-Air Battery and Method of Producing Air Electrode

Patent metadata

Field	Value
Publication number	US-2021249664-A1
Application number	US-201917049530-A
Country	US
Kind code	A1
Filing date	May 9, 2019
Priority date	May 18, 2018
Publication date	Aug 12, 2021
Grant date	—

Abstract

An object of the present invention is to improve the performance of a metal-air battery. The metal-air battery includes an air electrode, an anode, and an electrolyte sandwiched between the air electrode and the anode. The air electrode includes a co-continuous body having a three dimensional network structure formed by an integrated plurality of nanostructures having branches. A magnesium alloy is used for the anode, and a weak acidic salt containing no chloride ion or a salt considered to have a buffering capacity is used for the electrolyte. Consequently, the present invention can efficiently utilize electrons and suppress passivation and self corrosion of the anode, thereby improving the performance of the metal-air battery.

First claim

1 . A metal-air battery comprising:
an air electrode constituted by a co-continuous body having a three dimensional network structure in which a plurality of nanostructures is integrated through a noncovalent bond; an anode; and an electrolyte disposed between the air electrode and the anode and constituted by a salt containing no chloride ion.

2 . The metal-air battery according to claim 1 , wherein
the electrolyte is constituted by at least one of an acetate, a carbonate, a citrate, a phosphate, HEPES (4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid), a pyrophosphate or a metaphosphate.

3 . The metal-air battery according to claim 1 , wherein
the electrolyte is an electrolytic solution or a solid electrolyte in a range from weak acidity to neutrality.

4 . The metal-air battery according to claim 1 , wherein
the anode is constituted by at least one of magnesium, aluminum, calcium, iron or zinc.

5 . The metal-air battery according to claim 1 , wherein
the nanostructure of the air electrode is a nanosheet constituted by at least one of carbon, iron oxide, manganese oxide, zinc oxide, molybdenum oxide or molybdenum sulfide, or a nanofiber constituted by at least one of carbon, iron oxide, manganese oxide, zinc oxide, molybdenum oxide, molybdenum sulfide or cellulose; and the air electrode supports a catalyst constituted by at least one metal selected from iron, manganese, zinc, copper or molybdenum, or an oxide of at least one metal selected from calcium, iron, manganese, zinc, copper or molybdenum.

6 . A method for producing the air electrode of the metal-air battery according to claim 1 , comprising:
a gel production step of allowing a bacterium to produce a gel in which nanofibers made of iron oxide or manganese oxide are dispersed; a freezing step of freezing the gel; and a drying step of drying the frozen body of the gel.

7 . A method for producing the air electrode of the metal-air battery according to claim 1 , comprising:
a gel production step of allowing a bacterium to produce a gel in which nanofibers made of cellulose are dispersed; a freezing step of freezing the gel; a drying step of drying the frozen body of the gel; and a carbonization step of carbonizing the co-continuous body obtained by the drying, by heating in a gas atmosphere in which the cellulose is not burned.

8 . The metal-air battery according to claim 2 , wherein
the electrolyte is an electrolytic solution or a solid electrolyte in a range from weak acidity to neutrality.

9 . The metal-air battery according to claim 2 , wherein
the anode is constituted by at least one of magnesium, aluminum, calcium, iron or zinc.

10 . The metal-air battery according to claim 3 , wherein
the anode is constituted by at least one of magnesium, aluminum, calcium, iron or zinc.

11 . The metal-air battery according to claim 2 , wherein
the nanostructure of the air electrode is a nanosheet constituted by at least one of carbon, iron oxide, manganese oxide, zinc oxide, molybdenum oxide or molybdenum sulfide, or a nanofiber constituted by at least one of carbon, iron oxide, manganese oxide, zinc oxide, molybdenum oxide, molybdenum sulfide or cellulose; and the air electrode supports a catalyst constituted by at least one metal selected from iron, manganese, zinc, copper or molybdenum, or an oxide of at least one metal selected from calcium, iron, manganese, zinc, copper or molybdenum.

12 . The metal-air battery according to claim 3 , wherein
the nanostructure of the air electrode is a nanosheet constituted by at least one of carbon, iron oxide, manganese oxide, zinc oxide, molybdenum oxide or molybdenum sulfide, or a nanofiber constituted by at least one of carbon, iron oxide, manganese oxide, zinc oxide, molybdenum oxide, molybdenum sulfide or cellulose; and the air electrode supports a catalyst constituted by at least one metal selected from iron, manganese, zinc, copper or molybdenum, or an oxide of at least one metal selected from calcium, iron, manganese, zinc, copper or molybdenum.

13 . The metal-air battery according to claim 4 , wherein
the nanostructure of the air electrode is a nanosheet constituted by at least one of carbon, iron oxide, manganese oxide, zinc oxide, molybdenum oxide or molybdenum sulfide, or a nanofiber constituted by at least one of carbon, iron oxide, manganese oxide, zinc oxide, molybdenum oxide, molybdenum sulfide or cellulose; and the air electrode supports a catalyst constituted by at least one metal selected from iron, manganese, zinc, copper or molybdenum, or an oxide of at least one metal selected from calcium, iron, manganese, zinc, copper or molybdenum.

14 . A method for producing the air electrode of the metal-air battery according to claim 2 , comprising:
a gel production step of allowing a bacterium to produce a gel in which nanofibers made of iron oxide or manganese oxide are dispersed; a freezing step of freezing the gel; and a drying step of drying the frozen body of the gel.

15 . A method for producing the air electrode of the metal-air battery according to claim 3 , comprising:
a gel production step of allowing a bacterium to produce a gel in which nanofibers made of iron oxide or manganese oxide are dispersed; a freezing step of freezing the gel; and a drying step of drying the frozen body of the gel.

16 . A method for producing the air electrode of the metal-air battery according to claim 4 , comprising:
a gel production step of allowing a bacterium to produce a gel in which nanofibers made of iron oxide or manganese oxide are dispersed; a freezing step of freezing the gel; and a drying step of drying the frozen body of the gel.

17 . A method for producing the air electrode of the metal-air battery according to claim 5 , comprising:
a gel production step of allowing a bacterium to produce a gel in which nanofibers made of iron oxide or manganese oxide are dispersed; a freezing step of freezing the gel; and a drying step of drying the frozen body of the gel.

18 . A method for producing the air electrode of the metal-air battery according to claim 2 , comprising:
a gel production step of allowing a bacterium to produce a gel in which nanofibers made of cellulose are dispersed; a freezing step of freezing the gel; a drying step of drying the frozen body of the gel; and a carbonization step of carbonizing the co-continuous body obtained by the drying, by heating in a gas atmosphere in which the cellulose is not burned.

19 . A method for producing the air electrode of the metal-air battery according to claim 3 , comprising:
a gel production step of allowing a bacterium to produce a gel in which nanofibers made of cellulose are dispersed; a freezing step of freezing the gel; a drying step of drying the frozen body of the gel; and a carbonization step of carbonizing the co-continuous body obtained by the drying, by heating in a gas atmosphere in which the cellulose is not burned.

20 . A method for producing the air electrode of the metal-air battery according to claim 4 , comprising:
a gel production step of allowing a bacterium to produce a gel in which nanofibers made of cellulose are dispersed; a freezing step of freezing the gel; a drying step of drying the frozen body of the gel; and a carbonization step of carbonizing the co-continuous body obtained by the drying, by heating in a gas atmosphere in which the cellulose is not burned.

Assignees

• Nippon Telegraph & Telephone

Inventors

• Iwata Mikayo
• Nohara Masaya
• Sakamoto Shuhei
• Hayashi Masahiko
• Komatsu Takeshi

Classifications

• H01M2004/8689

  Positive electrodes · CPC title

• H01M4/9083

  on carbon or graphite · CPC title

• H01M4/9016

  Oxides, hydroxides or oxygenated metallic salts · CPC title

• H01M12/06

  with one metallic and one gaseous electrode · CPC title

• H01M2300/0014

  Alkaline electrolytes · CPC title