Hydrogen/Bromine Flow Battery in which Hydrogen is Freely Exchanged between Two Cell Compartments

Patent metadata

Field	Value
Publication number	US-2016308237-A1
Application number	US-201415104161-A
Country	US
Kind code	A1
Filing date	Dec 18, 2014
Priority date	Dec 19, 2013
Publication date	Oct 20, 2016
Grant date	—

Abstract

A flow battery system includes a first tank including a hydrogen reactant, a second tank including a bromine electrolyte, and at least one cell including a first electrolyte side operably connected to the first tank and a second electrolyte side operably connected to the second tank. The battery system further includes a direct connection line directly connecting the first tank and the second tank and configured such that the hydrogen reactant passes between the first tank and the second tank.

First claim

What is claimed is:

1 . A flow battery system, comprising:
a first tank including an hydrogen reactant; a second tank including a bromine electrolyte; at least one cell including a hydrogen reactant side operably connected to the first tank and a bromine electrolyte side operably connected to the second tank; and a direct connection line directly connecting the first tank and the second tank and configured such that the hydrogen reactant passes between the first tank and the second tank.

2 . The flow battery system of claim 1 , wherein the hydrogen reactant is in gas phase and the bromine electrolyte in the second tank is in a liquid phase.

3 . The flow battery system of claim 2 , further comprising:
a valve operably positioned between the second tank and the bromine electrode side of the battery cell; and a controller configured to operate the valve such that an electrode in the bromine electrolyte side of the battery cell is always immersed in the liquid phase bromine electrolyte.

4 . The flow battery system of claim 2 , wherein the second tank is configured such that the liquid phase bromine electrolyte fills a first portion of a volume of the second tank, and the first portion is equal to or greater than 90% of the volume of the second tank in a charged state of the battery system and in a discharged state of the battery system.

5 . The flow battery system of claim 4 , wherein the second tank includes a liquid-gas separator configured to float on an upper surface of the bromine electrolyte to separate the first portion from a remaining portion of the tank.

6 . The flow battery system of claim 5 , wherein the liquid-gas separator is selected from the group consisting of a cover, an oil, a bed of floating objects, a flexible head, a flexible internal enclosure, a piston, and a diaphragm.

7 . The flow battery system of claim 1 , wherein:
the bromine electrolyte side of the at least one cell includes a porous separator membrane; and the porous separator membrane is catalytically inactive with respect to the hydrogen reactant.

8 . The flow battery system of claim 1 , wherein the bromine electrolyte side of the at least one cell and the second tank are formed of materials that are catalytically inactive with respect to the hydrogen reactant.

9 . The flow battery system of claim 8 , wherein the bromine electrolyte side of the at least one cell and the second tank are formed of materials having an exchange current density of less than 10 −9 amps per square centimeter with respect to the hydrogen reactant.

10 . The flow battery system of claim 1 , wherein
the direct connection line includes a filter or polymer having an enhanced permeation rate for the hydrogen reactant compared to gas phase bromine; and the filter or polymer is configured such that the gas phase bromine entrained in the hydrogen reactant is separated from the hydrogen reactant.

11 . A flow battery system, comprising:
a first tank including an hydrogen reactant; a second tank including a bromine electrolyte; and at least one cell including an hydrogen reactant side operably connected to the first tank, a bromine electrolyte side operably connected to the second tank, and a separator between the first and second electrolyte sides configured to enable passage of the hydrogen reactant from the hydrogen reactant side to the bromine electrolyte side.

12 . The flow battery system of claim 11 , wherein:
the bromine electrolyte side of the at least one cell includes a porous separator membrane; and the porous separator membrane is catalytically inactive with respect to the first electrolyte.

13 . The flow battery system of claim 12 , further comprising:
a valve operably positioned between the second tank and the bromine electrode side of the battery cell; and a controller configured to operate the valve such that an electrode in the bromine electrolyte side of the battery cell is always immersed in liquid phase bromine electrolyte.

14 . The flow battery system of claim 12 , wherein the second tank is configured such that liquid phase bromine electrolyte fills a first portion of a volume of the second tank, and the first portion is equal to or greater than 90% of the volume of the second tank in a charged state of the battery system and in a discharged state of the battery system.

15 . The flow battery system of claim 14 , wherein the second tank includes a liquid-gas separator configured to float on an upper surface of the bromine electrolyte to separate the first portion from a remaining portion of the tank.

16 . The flow battery system of claim 15 , wherein the liquid-gas separator is selected from the group consisting of a cover, an oil, a bed of floating objects, a flexible head, a flexible internal enclosure, a piston, and a diaphragm.

17 . The flow battery system of claim 12 , wherein the bromine electrolyte side of the at least one cell and the second tank are formed of materials that are catalytically inactive with respect to the hydrogen reactant.

18 . The flow battery system of claim 17 , wherein the bromine electrolyte side of the at least one cell and the second tank are formed of materials having an exchange current density of less than 10 −9 amps per square centimeter with respect to the hydrogen reactant.

19 . The flow battery system of claim 12 , further comprising:
a connecting line operably connecting the first tank and the second tank such that a first pressure of H 2 in the first tank is substantially equal to a second pressure of H 2 gas in the second tank.

20 . The flow battery system of claim 19 , wherein:
the connecting line includes a filter or polymer having an enhanced permeation rate for the hydrogen reactant compared to gas phase bromine; and the filter or polymer is configured such that the gas phase bromine entrained in the hydrogen reactant is separated from the hydrogen reactant.

Assignees

• Bosch Gmbh Robert
• Univ California

Inventors

• Albertus Paul
• Knudsen Edward
• Tucker Michael C
• Cho Taek Kyu
• Weber Adam Z

Classifications

• H01M8/20

  Indirect fuel cells, e.g. fuel cells with redox couple being irreversible (H01M8/18 takes precedence) · CPC title

• H01M8/22

  Fuel cells in which the fuel is based on materials comprising carbon or oxygen or hydrogen and other elements; Fuel cells in which the fuel is based on materials comprising only elements other than carbon, oxygen or hydrogen · CPC title

• H01M8/188 Primary

  by recharging of redox couples containing fluids; Redox flow type batteries · CPC title

• H01M2250/10

  Fuel cells in stationary systems, e.g. emergency power source in plant · CPC title

• H01M8/184

  Regeneration by electrochemical means · CPC title