Metal complexes of substituted catecholates and redox flow batteries containing the same

Patent metadata

Field	Value
Publication number	US-2016149251-A1
Application number	US-201514952899-A
Country	US
Kind code	A1
Filing date	Nov 25, 2015
Priority date	Nov 26, 2014
Publication date	May 26, 2016
Grant date	—

Abstract

Active materials for flow batteries can include various coordination compounds formed from transition metals. Some compositions containing coordination compounds can include a substituted catecholate ligand having a structure of

in a neutral form or a salt form, in which Z is a heteroatom functional group bound to the substituted catecholate ligand at an open aromatic ring position and n is an integer ranging between 1 and 4. When more than one Z is present, each Z can be the same or different. Electrolyte solutions can include such coordination compounds, and such electrolyte solutions can be incorporated within a flow battery.

First claim

What is claimed is the following:

1 . A composition comprising:
a coordination compound comprising a substituted catecholate ligand, the substituted catecholate ligand having a structure of in a neutral form or a salt form;

wherein n is an integer ranging between 1 and 4, such that one or more Z are bound to the substituted catecholate ligand at an open aromatic ring position, each Z being the same or different when more than one Z is present; and
wherein Z is a heteroatom functional group selected from the group consisting of A 1 R A1 , A 2 R A2 , A 3 R A3 , and CHO;
wherein A 1 is —(CH 2 ) a — or —(CHOR)(CH 2 ) a —, R A1 is —OR 1 or —(OCH 2 CH 2 O) b R 1 , a is an integer ranging between 0 and about 6, with the proviso that R 1 is not H when a is 0 and R A1 is —OR 1 , and b is an integer ranging between 1 and about 10;
wherein R is H, C 1 -C 6 alkyl, heteroatom-substituted C 1 -C 6 alkyl, or C 1 -C 6 carboxyalkyl; and
wherein R 1 is H, methyl, ethyl, a C 2 -C 6 polyol bound through an ether linkage or an ester linkage, or C 1 -C 6 carboxyalkyl;

wherein A 2 is —(CH 2 ) c — or —CH(OR 2 )(CH 2 ) d —R A2 is —NR 3 R 4 , a carbon-linked amino acid, or —C(═O)XR 5 , X is —O— or —NR 6 —, c is an integer ranging between 0 and about 6, and d is an integer ranging between 0 and about 4;
wherein R 2 , R 3 , R 4 and R 6 are independently selected from the group consisting of H, C 1 -C 6 alkyl, or heteroatom-substituted C 1 -C 6 alkyl; and
wherein R 5 is H, C 1 -C 6 alkyl, heteroatom-substituted C 1 -C 6 alkyl, a C 2 -C 6 polyol bound through an ester linkage, a hydroxyacid bound through an ester linkage, a polyglycol acid bound through an ester linkage, an amino alcohol bound through an ester linkage or an amide linkage, an amino acid bound through an ester linkage or an amide linkage, or —(CH 2 CH 2 O) b R 1 ; and

wherein A 3 is —O— or —NR 2 —, R A3 is —(CHR 7 ) e OR 1 , —(CHR 7 ) e NR 3 R 4 , —(CHR 7 ) e C(═O)XR 5 , or —C(═O)(CHR 7 ) f R 8 , e is an integer ranging between 1 and about 6, with the proviso that e is not 1 when A 3 is —O—, and f is an integer ranging between 0 and about 6;
wherein R 7 is H or OH; and
wherein R 8 is H, C 1 -C 6 alkyl, heteroatom-substituted C 1 -C 6 alkyl, a C 2 -C 6 polyol bound through an ether linkage or an ester linkage, a hydroxyacid bound through an ether linkage or an ester linkage, a polyglycol acid bound through an ether linkage or an ester linkage, an amino alcohol bound through an ether linkage, an ester linkage, or an amide linkage, an amino acid bound through an ether linkage, an ester linkage, or an amide linkage, a carbon-linked amino acid, or —(OCH 2 CH 2 O) b R 1 .

2 . The composition of claim 1 , wherein the coordination compound has a formula of
D g M(L 1 )(L 2 )(L 3 ); wherein M is a transition metal, D is NH 4 + , Li + , Na + , or K + , g is an integer ranging between 0 and 6, and L 1 , L 2 and L 3 are ligands, at least one of L 1 , L 2 and L 3 being the substituted catecholate ligand.

3 . The composition of claim 2 , wherein at least two of L 1 , L 2 and L 3 are substituted catecholate ligands.

4 . The composition of claim 3 , wherein L 1 and L 2 are substituted catecholate ligands and L 3 is an unsubstituted catecholate ligand.

5 . The composition of claim 2 , wherein L 1 is the substituted catecholate ligand and L 2 and L 3 are unsubstituted catecholate ligands.

6 . The composition of claim 2 , wherein each of L 1 , L 2 and L 3 are substituted catecholate ligands.

7 . The composition of claim 2 , wherein the transition metal is Ti.

8 . The composition of claim 2 , wherein any of L 1 , L 2 and L 3 that are not substituted catecholate ligands comprise one or more ligands that are independently selected from the group consisting of an unsubstituted catecholate, ascorbate, citrate, glycolate, a polyol, gluconate, a hydroxyalkanoate, acetate, formate, benzoate, malate, maleate, phthalate, sarcosinate, salicylate, oxalate, a urea, a polyamine, aminophenolate, acetylacetonate, and lactate.

9 . The composition of claim 1 , wherein the substituted catecholate ligand has a structure selected from the group consisting of

10 . The composition of claim 1 , wherein the substituted catecholate ligand has a structure selected from the group consisting of

and any stereoisomer thereof.

11 . The composition of claim 1 , wherein the substituted catecholate ligand has a structure selected from the group consisting of

12 . An electrolyte solution comprising the composition of claim 1 .

13 . The electrolyte solution of claim 12 , wherein the electrolyte solution is an aqueous solution.

14 . The electrolyte solution of claim 13 , further comprising:
a buffer, a supporting electrolyte, a viscosity modifier, a wetting agent, or any combination thereof.

15 . The electrolyte solution of claim 13 , wherein the aqueous solution has a pH ranging between about 1 and about 13.

16 . The electrolyte solution of claim 13 , wherein the coordination compound has a formula of
D g M(L 1 )(L 2 )(L 3 ); wherein M is a transition metal, D is NH 4 + , Li + , Na + , or K + , g is an integer ranging between 0 and 6, and L 1 , L 2 and L 3 are ligands, at least one of L 1 , L 2 and L 3 being the substituted catecholate ligand.

17 . The electrolyte solution of claim 16 , wherein the transition metal is Ti.

18 . The electrolyte solution of claim 13 , wherein a concentration of the coordination compound in the aqueous solution ranges between about 0.5 M and about 3 M.

19 . A flow battery comprising an electrolyte solution comprising the composition of claim 1 .

20 . The flow battery of claim 19 , wherein the coordination compound has a formula of
D g M(L 1 )(L 2 )(L 3 ); wherein M is a transition metal, D is NH 4 + , Li + , Na + , or K + , g is an integer ranging between 0 and 6, and L 1 , L 2 and L 3 are ligands, at least one of L 1 , L 2 and L 3 being the substituted catecholate ligand.

21 . The flow battery of claim 20 , wherein the transition metal is Ti.

Assignees

• Lockheed Martin Advanced Energy Storage Llc

Inventors

• Reece Steven Y

Classifications

• Y02E60/50

  Fuel cells · CPC title

• C07F7/28 Primary

  Titanium compounds · CPC title

• H01M8/20

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

• H01M8/188 Primary

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

• H01M2300/0002

  Aqueous electrolytes · CPC title