CN104064784A - Method for improving stability of proton exchange membrane fuel cell - Google Patents

Method for improving stability of proton exchange membrane fuel cell Download PDF

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Publication number
CN104064784A
CN104064784A CN201310088956.7A CN201310088956A CN104064784A CN 104064784 A CN104064784 A CN 104064784A CN 201310088956 A CN201310088956 A CN 201310088956A CN 104064784 A CN104064784 A CN 104064784A
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China
Prior art keywords
vacuum
hydrophober
hole
carbon paper
base material
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CN201310088956.7A
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Chinese (zh)
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宋微
俞红梅
邵志刚
衣宝廉
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Dalian Institute of Chemical Physics of CAS
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Dalian Institute of Chemical Physics of CAS
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    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00Electrodes
    • H01M4/86Inert electrodes with catalytic activity, e.g. for fuel cells
    • H01M4/88Processes of manufacture
    • H01M4/8817Treatment of supports before application of the catalytic active composition
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00Electrodes
    • H01M4/86Inert electrodes with catalytic activity, e.g. for fuel cells
    • H01M4/96Carbon-based electrodes
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M8/00Fuel cells; Manufacture thereof
    • H01M8/02Details
    • H01M8/0202Collectors; Separators, e.g. bipolar separators; Interconnectors
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M8/00Fuel cells; Manufacture thereof
    • H01M8/02Details
    • H01M8/0202Collectors; Separators, e.g. bipolar separators; Interconnectors
    • H01M8/023Porous and characterised by the material
    • H01M8/0234Carbonaceous material
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02EREDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/30Hydrogen technology
    • Y02E60/50Fuel cells

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  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Sustainable Development (AREA)
  • Sustainable Energy (AREA)
  • Composite Materials (AREA)
  • Inert Electrodes (AREA)
  • Fuel Cell (AREA)

Abstract

The invention provides a method for improving stability of a proton exchange membrane fuel cell. A traditional carbon paper treating method leads to incapable uniform distribution of hydrophobic substances in carbon paper and easy water logging. The method is an improvement to carbon paper hydrophobic treating process on the basis of traditional methods; hydrophobization is carried out in a vacuum apparatus, so a water repellent is allowed to uniformly infiltrate into pores, thereby realizing uniform distribution of the water repellent and improving performance and stability of electrodes.

Description

A kind of method of improving Proton Exchange Membrane Fuel Cells stability
Technical field
The present invention relates to a kind of method that improves fuel battery stability, by improving the uniformity of hydrophober in gas diffusion layers, and then improve gas transport and water logging phenomenon.
Background technology
Fuel cell is a kind of energy conversion device, can be Hydrogen Energy is efficient, clean be converted into electric energy.In recent years, hydrogen energy fuel battery worldwide obtains support and development energetically, at present successfully Demonstration Application in a plurality of fields such as electric automobile, distributed power station, stand-by power supply, aviations.Wherein, Proton Exchange Membrane Fuel Cells is high with power density, toggle speed is fast, conversion efficiency is high, advantages of environment protection receives more concern.
The battery pack of Proton Exchange Membrane Fuel Cells is comprised of end plate, collector plate, bipolar plates, flow field and membrane electrode conventionally, the weight issue of its end plates, bipolar plates is the principal element that affects pile specific power, the structural design in flow field is the key factor that affects the inner gas-liquid distribution of pile and long-time running stability, and membrane electrode is the core component that affects pile output performance.Membrane electrode is comprised of the proton exchange membrane in the middle of being positioned at and Catalytic Layer, the diffusion layer of both sides.Proton exchange membrane in membrane electrode is responsible for to negative electrode, conducting hydrogen proton by anode, and the proton conductivity of film directly affects the Ohmic resistance of membrane electrode.Conventional proton exchange membrane is the perfluorinated sulfonic acid root proton exchange membrane that E.I.Du Pont Company produces, and the wetness degree of its proton conductivity and film is closely related.Catalytic Layer in membrane electrode is the place that hydrogen reduction and two kinds of electrochemical reactions of hydroxide occur, its output performance is by decisions such as catalyst activity, material proportion and microcellular structures, also needing has the proton conduction in enough wetting guarantee Catalytic Layer, but when the water yield is excessive, blockage of the micro orifice also can cause performance degradation.Diffusion layer in membrane electrode is be responsible for gas transport distribution and remove product water, the hydrophobicity in its duct and pore-size distribution are the key factors that affects battery performance, the water producing when battery surpass diffusion layer except outlet capacity time, can there is the water logging of diffusion layer, and then the transmission of obstruction gas, cause voltage drop.
Cost, life-span, environmental suitability etc. are several key issues greatly that affect fuel cell development always.The factor that wherein affects the pile life-span comprises again stability of material, electrode stability and flow field water management etc., and electrode stability is mainly closely related with its draining characteristics.The gas transport resistance of the drainability of gas diffusion layers when affecting battery operation, and then affect the limiting current density of electrode.In traditional gas diffusion layers hydrophobisation treatment process, it is that base material is immersed in hydrophober that the hydrophobisation of diffusion layer substrate is processed, hydrophober infiltrates the hole of base material by immersional wetting, this will cause the hydrophober of the surface impregnation higher concentration of base material, the hydrophober dipping that seldom measure base material center, when battery long-play, the center of base material is easy to occur water logging, affects the stability of battery.By adjusting the microcellular structure of gas diffusion layers, hydrophober in diffusion layer substrate hole is distributed uniformly, and then improve the eliminating efficiency of gas transport ability and aqueous water, be one of necessary ways that improve battery operation stability.
Patents: a kind of dewatering process method of fuel battery diffusion layer, application number 200710202617.1, a kind of dewatering process method of fuel battery diffusion layer is disclosed, it comprises gas diffusion layers dipping water-repelling agent, dry, roasting process, and the process of diffusion layer dipping water-repelling agent is carried out under ultrasonic environment.Can improve by this method the load capacity uniformity of water-repelling agent, improve conductivity, the gas permeability of gas diffusion layers.
Be with the obvious difference of documents, in the present invention, the dewatering process method of gas diffusion layers is to carry out in vacuum tank, or show to carry out at vacuum pumping platform, the former can make to form negative pressure in gas diffusion layers hole, hydrophober is impregnated in hole smoothly, and the latter can force hydrophober to be penetrated into opposite side from diffusion layer one side.
Summary of the invention
Object of the present invention, is by improving the homogeneity of hydrophober in electrode diffusion layer, improves performance and the stability of fuel cell.
For achieving the above object,
Improve a method for Proton Exchange Membrane Fuel Cells stability, the hydrophobisation process of diffusion layer substrate is to carry out in having the equipment of vacuum capability.
The hydrophobisation process of diffusion layer substrate is in the hole of diffusion layer substrate, to flood hydrophober to realize the hydrophobicity of hole.
Vacuum platform surface has spacing 1-5mm, the hole of diameter 0.1-0.2mm, and the hole on platform is connected with vacuum pump, utilizes the vacuum degree on vacuum pump implementation platform surface.
Described hydrophober comprises one or two or more kinds in PTFE, PVDF; Described base material comprises a kind of in porous carbon paper, carbon cloth.
The present invention has adopted the equipment with vacuum capability, this equipment comprises vacuum tank and vacuum platform, when gas diffusion layers base material being carried out to hydrophobic processing, base material is soaked in hydrophober, then the container of splendid attire hydrophober is placed in vacuum tank, control the absolute pressure of vacuum tank between 0-0.08MPa, in this process, vacuum environment can be extracted the gas in base material hole out, hydrophober is impregnated in the hole of base material uniformly and goes, and then improve the homogeneity that base material hydrophobisation is processed.Another kind of approach, when gas diffusion layers base material being carried out to hydrophobic processing, base material is placed on vacuum pumping platform, opening vacuum pump is adsorbed on platform base material, at substrate material surface, apply hydrophober, under the effect of vacuum pump, hydrophober can and be impregnated in hole uniformly through base material, and then improves the homogeneity that base material hydrophobisation is processed.
Tool of the present invention has the following advantages
1. by vacuumize processing when diffusion layer substrate hydrophobisation is processed, can make base material center also by hydrophober, be flooded, and then improve the distributing homogeneity of hydrophober.
2. by the raising of diffusion layer hydrophober distributing homogeneity, can avoid diffusion layer water logging, improve the stability of fuel cell operation.
Accompanying drawing explanation
Fig. 1 vacuum tank schematic diagram;
Fig. 2 vacuum platform schematic diagram; In figure: 1 is stuffing box, 2 is vacuum pump, and 3 is window;
The improvement of Fig. 3 the present invention to hydrophober distribution uniformity in diffusion layer substrate;
The improvement of Fig. 4 the present invention to battery performance;
The improvement of Fig. 5 the present invention to battery operation stability.
Embodiment
Embodiment 1
Carbon paper hydrophobic is processed:
Getting area is 3*3cm 2torayTGP-H-060 type carbon paper; carbon is immersed in the PTFE emulsion of 5wt.%; after drying, weigh; repeat to make several times PTFE concentration in carbon paper to reach 5wt.%; by soaked carbon paper under nitrogen protection in 320 degrees Celsius (can in 240-340 degree Celsius) lower roasting, form carbon paper a(traditional).
Get the carbon paper of same area, be immersed in the PTFE emulsion of the 5wt.% being positioned in vacuum tank, opening vacuum tank makes absolute pressure reach 0.02MPa, after 10min, take out carbon paper, dry and weigh, repeat to make several times PTFE concentration in carbon paper to reach 5wt.%, after 320 degrees Celsius of (can in 240-340 degree Celsius) roastings, form carbon paper b(of the present invention).
Carbon paper a and b have been carried out to scanning electron microscope analysis, as shown in Figure 3, in figure, can see the fibre structure of carbon paper, white portion is PTFE, can find out traditional carbon paper hydrophobic processing method by contrast, PTFE is more distributed in the both side surface of carbon paper, and the PTFE of center seldom; In the present invention, carbon paper is soaked to emulsion process and be placed in vacuum tank and carry out, can make PTFE enter the center of carbon paper, obviously improve the distribution of PTFE.
Embodiment 2
Carbon paper hydrophobic is processed: getting area is 10*3cm 2torayTGP-H-060 type carbon paper; carbon is immersed in the PTFE emulsion of 5wt.%, after drying, weighs, repeat to make several times PTFE concentration in carbon paper to reach 8wt.%; by soaked carbon paper under nitrogen protection in 320 degrees Celsius (can in 240-340 degree Celsius) lower roasting, form carbon paper c.
Get the carbon paper of same area, be immersed in the PTFE emulsion that is positioned over 5wt.% in vacuum tank, opening vacuum tank makes absolute pressure reach 0.05MPa, after 10min, take out carbon paper, dry and weigh, repeat to make several times PTFE concentration in carbon paper to reach 8wt.%, after 320 degrees Celsius of (can in 240-340 degree Celsius) roastings, form carbon paper d.
At above-mentioned carbon paper c and d surface, brush the slurry being formed by XC-72 and PTFE, under nitrogen protection, in 240-340 ° of lower roasting, form microporous layers.Utilize same CCM electrode, adopt above-mentioned two kinds of gas diffusion layers to suppress respectively effective area 27cm 2mEA, and be assembled into respectively monocell.
Figure 4 shows that the Evaluation results of two kinds of MEA, adopt as seen the method for the vacuum tank processing carbon paper hydrophobicity in the present invention obviously to improve the performance in electrode mass transport limitation district, improved the mass transfer characteristic of gas diffusion layers.
Embodiment 3
Carbon paper hydrophobic is processed: getting area is 10*30cm 2torayTGP-H-060 type carbon paper; carbon is immersed in the PTFE emulsion of 5wt.%, after drying, weighs, repeat to make several times PTFE concentration in carbon paper to reach 10wt.%; by soaked carbon paper under nitrogen protection in 320 degrees Celsius (can in 240-340 degree Celsius) lower roasting, form carbon paper e.
Get the carbon paper of same area, be placed on vacuum platform surface, open vacuum pump and make carbon paper be adsorbed on platform surface, and control vacuum pump pressure and reach 0.06MPa.PTFE emulsion at carbon paper surface-coated 5wt.%, vacuum action due to platform surface, PTFE emulsion can be forced to the hole through carbon paper, make the dipping PTFE of porous nickel, through after drying, weighing repeatedly, make PTFE concentration in carbon paper reach 10wt.%, after 320 degrees Celsius of (can in 240-340 degree Celsius) roastings, form carbon paper f.
At above-mentioned carbon paper e and f surface, brush the slurry being formed by acetylene black and PTFE, under nitrogen protection, in 240-340 ° of lower roasting, form microporous layers.Utilize same CCM electrode, adopt above-mentioned two kinds of gas diffusion layers to suppress respectively effective area 270cm 2mEA, and be assembled in a pile.
Figure 5 shows that the Evaluation results of two kinds of MEA, from figure, data can be found out, the carbon paper that adopts vacuum pumping method to process, and its battery performance is better than the carbon paper of conventional method, and at 1.5Acm -2after lower operation 1.2h, the electrode voltage of conventional method decay 20mV, and electrode voltage in the present invention is more stable, does not decay.

Claims (9)

1. a method of improving Proton Exchange Membrane Fuel Cells stability, is characterized in that: the hydrophobisation process of diffusion layer substrate is to carry out in having the equipment of vacuum capability.
2. in accordance with the method for claim 1, it is characterized in that: the hydrophobisation process of diffusion layer substrate is in the hole of diffusion layer substrate, to flood hydrophober to realize the hydrophobicity of hole.
3. it is characterized in that in accordance with the method for claim 1: the equipment with vacuum capability comprises vacuum tank or vacuum platform.
4. in accordance with the method for claim 3, it is characterized in that: vacuum platform surface has spacing 1-5mm, the hole of diameter 0.1-0.2mm, the hole on platform is connected with vacuum pump, utilizes the vacuum degree on vacuum pump implementation platform surface.
5. according to the method described in claim 3 or 4, it is characterized in that: the hydrophobisation process of diffusion layer substrate is that base material is placed on vacuum platform, at substrate material surface, brush hydrophober, the vacuum degree on vacuum platform surface makes hydrophober pass base material, is impregnated into uniformly in substrate hole.
6. it is characterized in that in accordance with the method for claim 5: its vacuum pump gauge pressure is between 0.05-0.08MPa.
7. in accordance with the method for claim 3, it is characterized in that: the hydrophobisation process of diffusion layer substrate is that hydrophober is placed in vacuum tank, base material is immersed in hydrophober, the vacuum degree absolute pressure of vacuum tank is 0-0.08MPa, vacuum environment is extracted the gas in base material hole out, and hydrophober is impregnated in hole uniformly.
8. according to the method described in claim 1,2,3,4,5 or 7, it is characterized in that: described hydrophober comprises one or two or more kinds in PTFE, PVDF; Described base material comprises a kind of in porous carbon paper, carbon cloth.
9. in accordance with the method for claim 1, it is characterized in that: the method for improving Proton Exchange Membrane Fuel Cells stability is by improving the uniformity of hydrophober in gas diffusion layers, and then improve gas transport and water logging phenomenon.
CN201310088956.7A 2013-03-20 2013-03-20 Method for improving stability of proton exchange membrane fuel cell Pending CN104064784A (en)

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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110983693A (en) * 2019-12-23 2020-04-10 武汉船用电力推进装置研究所(中国船舶重工集团公司第七一二研究所) Pretreatment method and device of carbon paper for gas diffusion layer of fuel cell
CN113991129A (en) * 2021-10-28 2022-01-28 无锡威孚高科技集团股份有限公司 Microporous layer of gas diffusion layer of proton exchange membrane fuel cell and preparation method thereof
CN114824307A (en) * 2022-03-15 2022-07-29 昀际科技(上海)有限责任公司 Batch hydrophobic treatment method for gas diffusion layers of fuel cells and production line thereof
CN116995251A (en) * 2023-09-26 2023-11-03 河南豫氢动力有限公司 High-performance gas diffusion layer for fuel cell and preparation method thereof

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20020134501A1 (en) * 2001-01-24 2002-09-26 Qinbai Fan Gas diffusion electrode manufacture and MEA fabrication
CN1770519A (en) * 2004-11-03 2006-05-10 比亚迪股份有限公司 Method for preparing fuel cell membrane electrode with integrative structure
CN101114713A (en) * 2006-07-25 2008-01-30 比亚迪股份有限公司 Fuel cell gaseous diffusion layer and process for producing fuel cell electrode and membrane electrode
CN101188302A (en) * 2007-12-07 2008-05-28 哈尔滨工业大学 Method for making film electrode component of proton exchange film fuel battery based on vibration method

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20020134501A1 (en) * 2001-01-24 2002-09-26 Qinbai Fan Gas diffusion electrode manufacture and MEA fabrication
CN1770519A (en) * 2004-11-03 2006-05-10 比亚迪股份有限公司 Method for preparing fuel cell membrane electrode with integrative structure
CN101114713A (en) * 2006-07-25 2008-01-30 比亚迪股份有限公司 Fuel cell gaseous diffusion layer and process for producing fuel cell electrode and membrane electrode
CN101188302A (en) * 2007-12-07 2008-05-28 哈尔滨工业大学 Method for making film electrode component of proton exchange film fuel battery based on vibration method

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110983693A (en) * 2019-12-23 2020-04-10 武汉船用电力推进装置研究所(中国船舶重工集团公司第七一二研究所) Pretreatment method and device of carbon paper for gas diffusion layer of fuel cell
CN113991129A (en) * 2021-10-28 2022-01-28 无锡威孚高科技集团股份有限公司 Microporous layer of gas diffusion layer of proton exchange membrane fuel cell and preparation method thereof
CN114824307A (en) * 2022-03-15 2022-07-29 昀际科技(上海)有限责任公司 Batch hydrophobic treatment method for gas diffusion layers of fuel cells and production line thereof
CN114824307B (en) * 2022-03-15 2023-10-10 上海碳际实业集团有限公司 Batch hydrophobic treatment method for gas diffusion layers of fuel cells and production line thereof
CN116995251A (en) * 2023-09-26 2023-11-03 河南豫氢动力有限公司 High-performance gas diffusion layer for fuel cell and preparation method thereof

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