Systems and reactors for storage of electrical energy

Patent metadata

Field	Value
Publication number	US-2022149415-A1
Application number	US-202017433355-A
Country	US
Kind code	A1
Filing date	Feb 25, 2020
Priority date	Feb 25, 2019
Publication date	May 12, 2022
Grant date	—

Abstract

The present invention relates to energy storage systems and reactors useful in such systems. Inventive reactors comprise a reaction vessel defining an inner volume and a compensation element, whereby said inner volume is filled with a fixed bed that is free of cavities and that comprises particles of formula (I), FeOx (I), where 0≤x≤1.5; said compensation element is adapted to adjust said inner volume. The reactors are inherently explosion proof and thus suited for domestic use. The systems are useful for compensating long-term fluctuations observed in production of renewable energy.

First claim

1 . A reactor comprising
a reaction vessel defining an inner volume, a compensation element, an inlet and an outlet, a heating element, an insulation,
wherein
said inner volume is filled with a fixed bed;
said fixed bed contains or consists of particles of formula (I), FeO x (I), where 0≤x≤1.5; and
said fixed bed is free of cavities having a volume larger than 10000 mm 3 and having principal radii that are at least 3 mm long, said principal radii being the three principal radii of the biggest ellipsoid that fits into the cavity;
said compensation element is adapted to adjust said inner volume.

2 . The reactor according to claim 1 , wherein the reaction vessel
defines an inner volume of 1-10 m 3 ; and/or is in the form of a cylinder or a sphere or a tube bundle; and/or does not contain means for agitation or transportation.

3 . The reactor according to claim 1 , wherein said compensation element
is adapted to compensate volume dilatation/compression during operation of the reactor; and/or is configured in the form of a membrane or in the form of a piston or in the form of a sponge or in the form of a fibrous material.

4 . The reactor according to claim 1 , wherein the inlet- and outlet
are adapted to fill and remove gases from said inner volume; are adapted to retain particulate material within the reactor; and/or are at the top (inlet) and bottom (outlet) of the reactor.

5 . The reactor according to claim 1 , further comprising one or more of the following elements:
a gas tank in fluid communication with said reaction vessel (containing an inert gas) to adjust gas pressure and volume during operation.

6 . An energy storage system comprising
a reactor according to claim 1 , said reactor being in fluid communication with a unit operating as a reversible fuel cell, a unit separating water from hydrogen.

7 . The system according to claim 6 , wherein said reversible fuel cell is replaced by an electrolyzer and a fuel cell, said electrolyzer being in fluid communication with said reactor, said fuel cell being in fluid communication with said separating unit.

8 . The system according to claim 6 , where said separating unit is replaced by two separating units, for charging and discharging mode.

9 . The system according to claim 6 , further comprising a microporous and hygroscopic material containing chamber within the reactor.

10 . A method for storing hydrogen, comprising the step of reducing a compound of formula (I) in a reactor as defined in claim 1 by feeding said reactor with a hydrogen-containing gas, thereby obtaining a reduced compound of formula (I) and water.

11 . A method for generating hydrogen, comprising the step of oxidizing a compound of formula (I) in a reactor as defined in claim 1 by feeding said reactor with water, thereby obtaining an oxidized compound of formula (I) and hydrogen.

12 . A method for storing electrical energy, said method comprising:
(a) electrolytically reducing water to obtain hydrogen; (b) reducing a compound of formula (I) in a reactor as defined in claim 1 by feeding said reactor with a hydrogen-containing gas, thereby obtaining a H 2 O/H 2 gaseous mixture; (c) separating H 2 from said gaseous mixture and recycle said H 2 into said reactor.

13 . A method for releasing electrical energy, said method comprising:
(d) oxidizing a compound of formula (I) in a reactor as defined in claim 1 by feeding said reactor with water, thereby obtaining an oxidized compound (I) and a H 2 O/H 2 gaseous mixture, (e) separating H 2 from said gaseous mixture, and (f) electrochemically reduce H 2 to obtain water and electrical energy.

14 . Use of a reactor according to claim 1 ,
for converting hydrogen to water and storing the thus obtained energy by reducing a compound of formula (I); and/or for converting water to hydrogen by oxidizing a compound of formula (I) thereby releasing the previously stored energy.

15 . Use of a system according to claim 6 for storing electrical energy, thereby charging said system; and/or for releasing electrical energy, thereby discharging said system.

Assignees

• Eth Zuerich

Inventors

• Stark Wendelin Jan
• Lustenberger Urs Benjamin

Classifications

• C01B3/10

  by reaction of water vapour with metals · CPC title

• H01M8/0656

  by electrochemical means (H01M8/065 takes precedence) · CPC title

• H01M8/065 Primary

  by dissolution of metals or alloys; by dehydriding metallic substances · CPC title

• H01M8/186 Primary

  by electrolytic decomposition of the electrolytic solution or the formed water product · 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