Two-electron redox catholyte for redox flow batteries
A redox flow battery comprising a two-electron, redox active, bridged, multi-cyclic compound (“TRBMC”) comprises a non-aromatic, bridged cyclic portion fused to an aromatic cyclic portion.
1. A redox flow battery comprising a two-electron, redox active, bridged, multi-cyclic compound (TRBMC) represented by Formula I:
wherein:
R 2 is a bond or alkylene;
R 3 and R 4 are individually H, alkyl, haloalkyl, phosphate, —[(CH 2 ) n —O] n′ —R 11 ;
R 5 , R 6 , R 7 , and R 8 are individually H, alkyl, haloalkyl, alkenyl, F, Cl, Br, I, NO 2 , CN, —[(CH 2 ) n —O] n′ —R 11 , aryl, aralkyl, or where any two may join together to form an aromatic or non-aromatic fused ring;
R 9 and R 18 are individually H, alkyl, F, Cl, Br, I, NO 2 , CN, aryl, or aralkyl;
each R 11 is individually H, alkyl, aryl, or aralkyl;
n is an integer from 0 to 25; and
n′ is an integer from 0 to 25.
2. The redox flow battery of claim 1 , wherein the TRBMC comprises an annulated anthracene ether compound.
3. The redox flow battery of claim 1 , wherein R 2 is C 1 -C 4 -alkylene.
4. The redox flow battery of claim 3 , wherein R 2 is methylene, ethylene, n-propylene, or iso-propylene.
5. The redox flow battery of claim 1 , wherein R 2 is ethylene.
6. The redox flow battery of claim 1 , wherein R 3 and R 4 are individually H, alkyl, or —[(CH 2 ) n —O] n′ —R 11 .
7. The redox flow battery of claim 1 , wherein R 5 , R 6 , R 7 , and R 8 are individually H or alkyl, or where any two may join together to form a ring.
8. The redox flow battery of claim 1 , wherein R 9 and R 10 are individually H or alkyl.
9. The redox flow battery of claim 1 , wherein each R H is individually H or alkyl.
10. The redox flow battery of claim 1 , wherein n is an integer from 1 to 10; and n′ is an integer from 1 to 10.
11. The redox flow battery of claim 1 , wherein:
R 2 is methylene or ethylene;
R 3 and R 4 are individually H, alkyl, or —[(CH 2 ) n —O] n′ —R 11 ;
R 5 , R 6 , R 7 , and R 8 are individually H;
R 9 and R 10 are individually H, methyl, ethyl, n-propyl, iso-propyl, n-butyl, sec-butyl, iso-butyl, or tert-butyl;
each R 11 is individually H or alkyl;
n is an integer from 1 to 10; and
n′ is an integer from 1 to 10.
12. The redox flow battery of claim 1 , wherein the TRBMC comprises 9,10-bis(2-methoxyethoxy)-1,2,3,4-tetrahydro-1,4-methanoanthracene.
13. The redox flow battery of claim 1 that is non-aqueous.
14. A method of operating a redox flow battery, the method comprising providing the redox flow battery of claim 1 .
15. The method of claim 14 , wherein the TRBMC comprises 9,10-bis(2-methoxyethoxy)-1,2,3,4-tetrahydro-1,4-methanoanthracene.
16. A redox flow battery comprising 9,10-bis(2-methoxyethoxy)-1,2,3,4-tetra hydro-1,4-ethanoanthracene.
17. A method of operating a redox flow battery, the method comprising providing the redox flow battery of claim 16 .