Anaerobic Aluminum-Water Electrochemical Cell

Patent metadata

Field	Value
Publication number	US-2019020084-A1
Application number	US-201816057086-A
Country	US
Kind code	A1
Filing date	Aug 7, 2018
Priority date	Dec 4, 2012
Publication date	Jan 17, 2019
Grant date	—

Abstract

An anaerobic aluminum-water electrochemical cell is provided. The electrochemical cell includes: a plurality of electrode stacks, each electrode stack featuring an aluminum or aluminum alloy anode, and at least one cathode configured to be electrically coupled to the anode; one or more physical separators between each electrode stack adjacent to the cathode; a housing configured to hold the electrode stacks, an electrolyte, and the physical separators; a water injection port, in the housing, configured to introduce water into the housing; and an amount of hydroxide base sufficient to form an electrolyte having a hydroxide base concentration of at least 0.5% to at most 13% of the saturation concentration when water is introduced between the anode and the least one cathode.

First claim

1 . An anaerobic aluminum-water electrochemical cell comprising:
a plurality of electrode stacks, each electrode stack comprising an aluminum or aluminum alloy anode, and at least one cathode configured to be electrically coupled to the anode; one or more physical separators between each electrode stack adjacent to the cathode; a housing configured to hold the electrode stacks, an electrolyte, and the physical separators; a water injection port, in the housing, configured to introduce water into the housing; and an amount of hydroxide base sufficient to form an electrolyte having a hydroxide base concentration of at least 0.5% to at most 13% of the saturation concentration when water is formed or introduced between the anode and the least one cathode.

2 . The electrochemical cell according to claim 1 , wherein the amount of hydroxide base is sufficient to form an electrolyte having a hydroxide base concentration of at least 1% to at most 12% of the saturation concentration.

3 . The electrochemical cell according to claim 1 , wherein the amount of hydroxide base is sufficient to form an electrolyte having a hydroxide base concentration of at least 1.5% to at most 10% of the saturation concentration.

4 . The electrochemical cell according to claim 1 , wherein the amount of hydroxide base is sufficient to form an electrolyte having a hydroxide base concentration of at least 7% to at most 13% of the saturation concentration.

5 . The electrochemical cell according to claim 1 , the cathode having a surface characterized by an electrochemical roughness factor of at least 5.

6 . The electrochemical cell according to claim 1 , wherein the aluminum of the anode has a purity of at least 99.95 wt %.

7 . The electrochemical cell according to claim 1 , wherein the aluminum or aluminum alloy of the anode has a purity of at 99.99 wt %.

8 . The electrochemical cell according to claim 1 , wherein the water injection port is configured to introduce the water into the housing so that the water flows through the physical separators.

9 . An aluminum-water electrochemical system comprising:
an aluminum-water electrochemical cell according to claim 1 ; a waste separation system in fluid communication with the housing and configured to receive electrolyte and aluminum hydroxide waste from the aluminum-water electrochemical cell and to separate the aluminum hydroxide waste from the electrolyte; and a fuel injector, in fluid communication with the waste separation system and the water injection port, configured to receive the electrolyte from the waste separation system and to provide the electrolyte to the water injection port.

10 . The electrochemical system according to claim 9 , wherein the fuel injector is further configured to receive water from a water supply.

11 . The electrochemical system according to claim 9 , wherein each electrode stack includes two cathodes on either side of the anode.

12 . The electrochemical system according to claim 9 , further comprising an aqueous electrolyte.

13 . The electrochemical system according to claim 12 , wherein the electrolyte includes water and sodium chloride.

14 . A method for generating an electrical current using an electrochemical cell comprising: a plurality of electrode stacks, each electrode stack comprising an aluminum or aluminum alloy anode, and at least one cathode configured to be electrically coupled to the anode; one or more physical separators between each electrode stack adjacent to the cathode;
a housing configured to hold the electrode stacks, an electrolyte, and the physical separators; and a water injection port, in the housing, configured to introduce water into the housing, wherein the electrolyte includes a hydroxide base in an amount of at least 0.5% to at most 13% of the saturation concentration, the method comprising: introducing water between an anode and at least one cathode of the electrochemical cell, to form the electrolyte; anaerobically oxidizing aluminum or an aluminum alloy; and electrochemically reducing water at the at least one cathode.

15 . The method according to claim 14 , wherein the electrolyte includes the hydroxide base in an amount of at least 1% to at most 12% of the saturation concentration.

17 . The method according to claim 14 , wherein the electrolyte includes the hydroxide base in an amount of at least 1.5% to at most 10% of the saturation concentration.

18 . The method according to claim 14 , wherein the electrolyte includes the hydroxide base in an amount of at least 7% to at most 13% of the saturation concentration.

19 . The method according to claim 14 , the cathode having a surface characterized by an electrochemical roughness factor of at least 5.

20 . The method according to claim 15 , wherein the water includes sodium chloride.

Assignees

• Massachusetts Inst Technology

Inventors

• Mckay Ian Salmon
• Macdonald Ruaridh R
• Milnes Thomas B

Classifications

• H01M2300/0014

  Alkaline electrolytes · CPC title

• H01M4/463

  Aluminium based · CPC title

• H01M12/065

  with plate-like electrodes or stacks of plate-like electrodes · CPC title

• H01M8/04828

  Humidity; Water content · CPC title

• H01M12/04

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