USE OF POROUS MEMBRANE AND COMPOSITE MEMBRANE THEREOF IN REDOX FLOW ENERGY STORAGE BATTERY

• US 20130252137A1
• Filed: 07/08/2011
• Published: 09/26/2013
• Est. Priority Date: 12/10/2010
• Status: Active Grant

• Current Assignee: Dalian Institute of Chemical Physics Chinese Academy of Sciences, Dalian Rongke Power Co., Ltd.
• Original Assignee: Dalian Rongke Power Co., Ltd.
• Inventors: Zhang, Huamin, Li, Xianfeng, Zhang, Hongzhang, Shi, Dingqin
• Granted Patent: US 9,123,923 B2
• Time in Patent Office: Days
• US Class Current: 429/516
• CPC Class Codes: C08J 2327/16 Homopolymers or copolymers of vinylidene fluoride
• CPC Class Codes: C08J 5/22 Films, membranes or diaphragms
• CPC Class Codes: C08J 5/2293 After-treatment of fluorine-containing membranes
• CPC Class Codes: H01M 8/0293 Matrices for immobilising electrolyte solutions
• CPC Class Codes: H01M 8/1018 Polymeric electrolyte materials
• CPC Class Codes: H01M 8/1067 characterised by their physical properties, e.g. porosity, ionic conductivity or thickness
• CPC Class Codes: H01M 8/1088 Chemical modification, e.g. sulfonation
• CPC Class Codes: H01M 8/188 by recharging of redox couples containing fluids; Redox flow type batteries
• CPC Class Codes: H01M 8/20 Indirect fuel cells, e.g. fuel cells with redox couple being irreversible H01M8/18 takes precedence
• CPC Class Codes: Y02E 60/50 Fuel cells
• CPC Class Codes: Y02P 70/50 Manufacturing or production processes characterised by the final manufactured product

Abstract

Disclosed is use of a porous membrane and a composite membrane thereof in a redox flow batteries, and in particular the use thereof in a vanadium redox flow battery. The membrane can effectively realize the separation of ions with different valence states, and an ion transfer without any ion exchange group. The pore size and structure of the porous membrane can be controlled by filling an inorganic substance or grafting an ion exchange group in the pore, in order to improve the barrier properties of the porous membrane for vanadium ions and to increase proton conductivity.

Claims

1. A redox flox battery comprising a porous membrane or a composite membrane, wherein said porous membrane is made of at least one type of organic high molecular weight resin, said composite membrane is prepared via grafting ion exchange groups on the surface or pores of the porous membrane or doping inorganic particles in the pores of the porous membrane, the pore size, porosity, and thickness of said porous membrane and composite membrane are 0.05˜

100 nm, 5˜

90% and 20˜

500 μ

m, respectively.

2. The battery of claim 1, wherein said organic high molecular weight resin is polysulfone (PSF), polyketone, polyimide (PI), polybenzimidazole, polyvinylidene fluoride (PVDF), polyvinyl pyridine, polyacrylonitrile (PAN), polypropylene, polyethylene, polybutadiene, or cellulose acetate.

4. The battery of claim 1, wherein said composite membrane is prepared via doping inorganic particles in the pores based on the porous membranes;

the weight ratio of the inorganic substances is in the range of 1˜

30%.

5. The battery of claim 4, wherein the inorganic particles are SiO₂, ZrO₂, TiO₂, PbO₂, WO₃, ZrPO₃, or their combinations.

6. The battery of claim 1, wherein said composite membrane is prepared via grafting ion exchange groups on the surface or pores of the porous membranes;

the weight ratio of ion exchange groups is in the range of 0.1˜

30%.

7. The battery of claim 6, wherein said ion exchange groups are sulfonated polystyrene groups or aminated polystyrene groups;

said composite membrane is prepared via sulfonating or aminating of PS grafted on a porous membrane;

or, in the alternative, said composite membrane is prepared via grafting sulfonated PS or aminated PS on a porous membrane.

8. The battery of claim 1, wherein said redox flow battery is selected from the group consisting of vanadium flow battery, V/Br flow battery, Zn/Ce flow battery, and Fe/Cr flow battery.

3. (canceled)

9. A porous composite membrane, wherein said porous composite membrane is prepared via grafting an ion exchange group on the surface or pores of a PVDF porous membrane;

the ion exchange group is a sulfonated polystyrene group or an aminated polystyrene group;

the amount of the ion exchange group is 0.1˜

30% based on the total weight of the porous composite membrane;

the membrane is prepared as follows;

polystyrene is grafted onto a porous membrane;

the porous composite membrane is then prepared via sulfonating or aminating of the polystyrene grafted onto the porous membrane;

or, in the alternative, said porous composite membrane is prepared via grafting sulfonated polystyrene or aminated polystyrene onto a porous membrane;

the thickness, pore size and porosity of said porous composite membrane are 20˜

500 μ

m, 0.05˜

100 nm, and 5˜

90%, respectively.

10. The porous composite membrane of claim 9, wherein said porous composite membrane is prepared by the following method:

(1) PVDF is dissolved in an organic solvent and kept stifling at 20˜

100°

C. for 0.5˜

10 h to form a polymer solution;

the amount of the PVDF is in the range of 5˜

70% based on the total weight of the polymer solution;

a volatile solvent is optionally added into said organic solvent to form a mixture, the amount of the volatile solvent is in the range of 0˜

50% based on the total weight of the mixture;

(2) the polymer solution prepared by step (1) is cast on a non-woven fabric or a glass substrate;

after evaporation for 0˜

60 s, the substrate is immersed into a poor solvent for resin at −

20˜

100°

C. for 5˜

600 s to form the porous membrane with a thickness of 20˜

500 μ

m;

(3) the membrane prepared by step (2) are immersed into a KOH alcoholic solution at −

10˜

80°

C. for 1˜

10 h;

(4) the membrane prepared by step (3) is immersed into a PS THF'"'"'s solution at −

15˜

60°

C. for 0.5˜

60 h;

(5) the membrane prepared by step (4) is immersed into a sulfonating reagent at 0˜

100°

C. for 0.5˜

10 h to form the porous membrane;

or, in the alternative, the membrane prepared by step (4) is immersed into a chloromethylation reagent at −

20˜

100°

C. for 0.5˜

20 h, and the resulted membrane is immersed into a 5˜

60 wt % TMA aqueous solution for 2˜

48 h to form to PVDF porous membrane;

said sulfonating reagent is selected from the group consisting of 95˜

98% H₂SO₄, chlorosulfonic acid, fuming sulphuric acid, sulphite, and combinations thereof;

said chloromethylation reagent is selected from the group consisting of chloromethyl ether, dibemethine, chlorine methyl alkyl ether, (HCHO)n-HCl, and combinations thereof;

said aminomethylating reagent is selected from the group consisting of trimethylamine, triethylamine, dimethylamine, diethylamine, and combinations thereof;

said organic solvent is selected from the group consisting of DMSO, DMAC, NMP, DMF, and combinations thereof;

said volatile non-solvent is selected from the group consisting of methanol, tetrahydrofuran, n-hexane, and combinations thereof;

said poor solvent for polymer is selected from the group consisting of water, methanol, alcohol, propanol, isopropanol, and combinations thereof;

the concentration of said KOH alcoholic solution is in the range of 1˜

10 wt %; and

the concentration of said styrene solution is in the range 1˜

90 wt %.