MEMBRANES FOR AQUEOUS REDOX FLOW BATTERIES

1 . A membrane comprising a polyamine polymer.

2 . The membrane of claim 1 , wherein the polyamine polymer is a zwitterionic quaternary polyamine polymer.

3 . The membrane of claim 1 , wherein the membrane allows monoatomic and monovalent ions and/or the acid/base dissociation products of water to permeate the membrane such that the conductivity of the membrane is at least 0.01 mS/cm and the diffusive permeability of polyvalent ions and/or ionic transition metal complexes is limited to less than 1×10 −8 cm 2 /s.

4 . The membrane of claim 3 , wherein the monoatomic and monovalent ions are independently H + , Li + , Na + , K + , F − , Cl − , Br − , or I − .

5 . The membrane of claim 3 , wherein the polyvalent ions are independently S 2 2− , S 4 2− , S 8 2− , MnO 4 − , or MnO 4 2− .

6 . The membrane of claim 1 , wherein the membrane filters aqueous or non-aqueous electrolytes in electrochemical applications.

7 . The membrane of claim 1 , wherein the polyamine polymer comprises a Tröger's base polymer or copolymer thereof.

8 . The membrane of claim 1 , wherein the polyamine polymer comprises a repeat unit of Formula J:

wherein:

Y is absent or —CH 2 —;

R 1a and R 1b are each independently absent, hydrogen, C 1-6 alkyl, -L 1 -S(O) 2 O − , -L 1 -C(O)O − , or -L 1 -P(O) 2 O − , such that at least one of R 1a and R 1b is C 1-6 alkyl, -L 1 -S(O) 2 O − , -L 1 -C(O)O − , or -L 1 -P(O) 2 O − ;

each L 1 is independently C 1-6 alkylene;

alternatively, R 1a and R 1b on different polymers can combine to form a crosslinker;

R 2a and R 2b are each independently C 1-6 alkyl or C(O)O − ;

alternatively, R 2a and R 2b on different polymers can combine to form a crosslinker; and

A is a bond, optionally substituted C 1-6 alkylene, urethane, amide, sulfone, ester, ether, a linker, or combined with the adjacent rings to form an optionally substituted C 6-20 bicyclic cycloalkyl.

9 . The membrane of claim 8 , wherein:

R 1a and R 1b are each independently absent, hydrogen, C 1-3 alkyl, or -L 1 -S(O) 2 O − , and L 1 is a C 2-4 alkylene;

alternatively, R 1a and R 1b on different polymers can combine to form a crosslinker, wherein the crosslinker is C 3-10 alkylene or C 3-10 haloalkylene.

10 . The membrane of claim 8 , wherein:

R 1a and R 1b are each independently absent, hydrogen, methyl, or —CH 2 CH 2 CH 2 S(O) 2 O − ;

alternatively, R 1a and R 1b on different polymers can combine to form a crosslinker, wherein the crosslinker is

11 . The membrane of claim 8 , wherein:

R 1a and R 1b on different polymers can combine to form a crosslinker, wherein the crosslinker is

and

wherein R is C 2-10 alkylene, poly(ethylene glycol), arylene or heteroarylene.

12 . The membrane of claim 8 , wherein

R 1a and R 1b are each independently hydrogen, methyl, or —CH 2 CH 2 CH 2 S(O) 2 O − ;

alternatively, R 1a and R 1b on different polymers can combine to form a crosslinker, wherein the crosslinker is

wherein n=1-12.

13 . The membrane of claim 8 , wherein:

R 2a and R 2b are each independently C 1-3 alkyl;

alternatively, R 2a and R 2b on different polymers can combine to form a crosslinker, wherein the crosslinker is C 3-10 alkylene, C 3-10 haloalkylene,

14 . The membrane of claim 8 , wherein:

R 2a and R 2b are each independently methyl;

alternatively, R 2a and R 2b on different polymers can combine to form a crosslinker, wherein the crosslinker is

15 . The membrane of claim 8 , wherein A is a bond, methylene, ethylene, propylene, butylene, urethane, amide, sulfone, ester, ether,

wherein R is a C 1-12 alkylene, and n is 0 to 20.

16 . The membrane of claim 8 , wherein A is a bond, sulfone, ester, ether,

and

wherein R is a C 1-12 alkylene, and n is 0 to 20.

17 . The membrane of claim 1 , wherein the polyamine polymer is

wherein:

X is

 and

X′ is

18 . The membrane of claim 1 , wherein the polyamine polymer is

19 . The membrane of claim 1 , wherein the polyamine polymer is

20 . The membrane of claim 1 , wherein the polyamine polymer is

wherein

X is

 and

X′ is

21 . The membrane of claim 1 , wherein the polyamine polymer is

22 . The membrane of claim 1 , wherein the polyamine polymer is

23 . The membrane of claim 1 , wherein the polyamine polymer membrane is a composite with a metal oxide.

24 . The membrane of claim 1 , wherein the polyamine polymer membrane is a composite with manganese dioxide.

25 . A composition comprising a polyamine polymer of Formula J:

wherein:

Y is absent or —CH 2 —;

R 1a and R 1b are each independently absent, hydrogen, C 1-6 alkyl, -L 1 -S(O) 2 O − , -L 1 -C(O)O − , or -L 1 -P(O) 2 O − , such that at least one of R 1a and R 1b is C 1-6 alkyl, -L 1 -S(O) 2 O − , -L 1 -C(O)O − , or -L 1 -P(O) 2 O − ;

each L 1 is independently C 1-6 alkylene;

alternatively, R 1a and R 1b on different polymers can combine to form a crosslinker;

R 2a and R 2b are each independently C 1-6 alkyl or C(O)O − ;

alternatively, R 2a and R 2b on different polymers can combine to form a crosslinker; and

A is a bond, optionally substituted C 1-6 alkylene, urethane, amide, sulfone, ester, ether, a linker, or combined with the adjacent rings to form an optionally substituted C 6-20 bicyclic cycloalkyl.

26 . The composition of claim 25 , wherein:

R 1a and R 1b are each independently absent, hydrogen, C 1-3 alkyl, or -L 1 -S(O) 2 O − , and L 1 is a C 2-4 alkylene;

alternatively, R 1a and R 1b on different polymers can combine to form a crosslinker, wherein the crosslinker is C 3-10 alkylene or C 3-10 haloalkylene.

27 . The composition of claim 25 , wherein:

R 1a and R 1b are each independently absent, hydrogen, methyl, or —CH 2 CH 2 CH 2 S(O) 2 O − ;

alternatively, R 1a and R 1b on different polymers can combine to form a crosslinker, wherein the crosslinker is

28 . The composition of claim 25 , wherein:

R 1a and R 1b on different polymers combine to form a crosslinker, wherein the crosslinker is

wherein R is C 2-10 alkyl, poly(ethylene glycol), aryl or heteroaryl.

29 . The composition of claim 25 , wherein:

R 1a and R 1b are each independently a hydrogen atom, methyl, or —CH 2 CH 2 CH 2 S(O) 2 O − ;

alternatively, R 1a and R 1b on different polymers can combine to form a crosslinker, wherein the crosslinker is

wherein n=1-12.

30 . The composition of claim 25 , wherein:

R 2a and R 2b are each independently C 1-3 alkyl;

alternatively, R 2a and R 2b on different polymers can combine to form a crosslinker, wherein the crosslinker is C 3-10 alkylene, C 3-10 haloalkylene,

31 . The composition of claim 25 , wherein:

R 2a and R 2b are each independently methyl;

alternatively, R 2a and R 2b on different polymers can combine to form a crosslinker, wherein the crosslinker is

32 . The composition of claim 25 , wherein A is a bond, methylene, ethylene, propylene, butylene, urethane, amide, sulfone, ester, ether,

and

wherein R is a C 1-12 alkylene, and n is 0 to 20.

33 . The composition of claim 25 , wherein A is a bond, sulfone, ester, ether,

and

wherein R is a C 1-12 alkylene, and n is 0 to 20.

34 . The composition of claim 25 , wherein the polyamine polymer is

and

wherein

X is

 and

X′ is

35 . The composition of claim 25 , wherein the polyamine polymer is

36 . The composition of claim 25 , wherein the polyamine polymer is

37 . The composition of claim 25 , wherein the polyamine polymer is

wherein:

X is

 and

X′ is

38 . The composition of claim 25 , wherein the polyamine polymer is

39 . The composition of claim 25 , wherein the polyamine polymer is

40 . (canceled)

41 . An electrochemical cell comprising:

a) a posolyte comprising a positive electrode active material dissolved in an electrolyte;

b) a negolyte comprising a polysulfide compound dissolved in an electrolyte;

c) an ion-permeable membrane configured to electrically insulate the negolyte from the posolyte; and

d) wherein the membrane comprises:

(i) a polymer;

(ii) a protective layer disposed on a posolyte side of the polymer and configured to reduce oxidation of the polymer by the positive electrode active material; and

(iii) wherein the protective layer comprises manganese oxide.

42 . An electrochemical cell comprising:

a) a posolyte comprising a positive electrode active material dissolved in an electrolyte;

b) an negolyte comprising a polysulfide compound dissolved in an electrolyte;

c) an ion-permeable membrane configured to electrically insulate the negolyte from the posolyte; and

d) wherein the membrane comprises an anion exchange membrane (AEM), a cation exchange membrane (CEM), a zwitterionic membrane, a porous membrane with average pore diameter smaller than 10 nanometers, a polybenzimidazole-based membrane, a polysulfone-based membrane, a polyetherketone-based membrane, a membrane including polymers of intrinsic microporosity (PIM), or a combination thereof.

43 . An electrochemical cell comprising:

a) a posolyte comprising a positive electrode active material dissolved in an electrolyte; wherein the positive electrode active material comprises a manganese-based compound;

b) a negolyte comprising a polysulfide compound dissolved in an electrolyte;

c) an ion-permeable membrane configured to electrically insulate the negolyte from the posolyte; and

d) wherein the membrane comprises:

(i) a composite membrane comprising an inorganic material and an organic material; and

(ii) wherein the organic material comprises a polyether ether ketone (PEEK), a polysulfone, a polystyrene, a polypropylene, a polyethylene, or any combination thereof.