阅读说明：本技术 一种全钒液流电池双极板及其制备方法 (Full-vanadium redox flow battery bipolar plate and preparation method thereof ) 是由 张彦芳 于 2018-07-03 设计创作，主要内容包括：本发明涉及一种全钒液流电池双极板及其制备方法,所述制备方法包括以下步骤：在导电碳纤维两侧的表面涂覆导电复合粘合剂,通过所述导电复合粘合剂在导电碳纤维两侧的表面贴合柔性石墨纸,并重复以上步骤,以形成不同的厚度,然后放入平板热压机中进行热压固化,得到全钒液流电池双极板。本发明的有益效果在于,提供一种成本低且工艺简单的全钒液流电池双极板的制备方法；且制备得到的全钒液流电池双极板具有良好的导电性以及耐腐蚀性的特点,同时还具有厚度均匀以及密封性能好的优点。(The invention relates to an all-vanadium redox flow battery bipolar plate and a preparation method thereof, wherein the preparation method comprises the following steps: coating conductive composite adhesive on the surfaces of two sides of the conductive carbon fiber, attaching flexible graphite paper on the surfaces of the two sides of the conductive carbon fiber through the conductive composite adhesive, repeating the steps to form different thicknesses, and then putting the conductive carbon fiber into a flat plate hot press for hot pressing and curing to obtain the all-vanadium redox flow battery bipolar plate. The preparation method has the beneficial effects that the preparation method of the bipolar plate of the all-vanadium redox flow battery is low in cost and simple in process; the prepared all-vanadium redox flow battery bipolar plate has the characteristics of good conductivity and corrosion resistance, and also has the advantages of uniform thickness and good sealing performance.)

1. A preparation method of a bipolar plate of an all-vanadium redox flow battery is characterized by comprising the following steps: the preparation method comprises the following steps: coating conductive composite adhesive on the surfaces of two sides of the conductive carbon fiber, attaching flexible graphite paper on the surfaces of the two sides of the conductive carbon fiber through the conductive composite adhesive, repeating the steps to form different thicknesses, and then putting the conductive carbon fiber into a flat plate hot press for hot pressing and curing to prepare the all-vanadium redox flow battery bipolar plate.

2. The method for preparing the bipolar plate of the all-vanadium flow battery according to claim 1, wherein the conductive carbon fiber is JD-10 type conductive carbon fiber.

3. The preparation method of the all-vanadium flow battery bipolar plate according to claim 1, wherein the preparation method of the conductive composite adhesive comprises the following steps:

adding 55-65% by mass of aqueous polytetrafluoroethylene emulsion into a reaction kettle, adding 15-25% by mass of conductive carbon fiber short and short fibers for heating polymerization, adding 2.5-7% by mass of adhesion promoter (TPU) into the reaction kettle when the temperature is increased to 80 ℃, continuing heating the reaction kettle, stopping heating when the temperature is increased to 360 ℃, and cooling to normal temperature to prepare the aqueous conductive composite adhesive.

4. The preparation method of the bipolar plate of the all-vanadium redox flow battery of claim 3, wherein in the preparation method of the conductive composite adhesive, 2.5-7% by mass of an adhesion promoter is added when the temperature is increased to 80 ℃, the temperature of a reaction kettle is continuously increased, 3% by mass of an adhesion promoter emulsion is added into the reaction kettle once when the temperature is increased by 80 ℃ and the temperature of the reaction kettle is stopped when the temperature is increased to 360 ℃.

5. The preparation method of the all-vanadium flow battery bipolar plate according to claim 2, wherein the preparation method of the flexible graphite paper comprises the following steps: and uniformly spraying the aqueous conductive composite adhesive on two sides of the conductive carbon fibers, uniformly spraying expanded graphite powder in an expanded graphite powder bin, and rolling by using a calendering roller to form the flexible graphite paper.

6. The bipolar plate of the all-vanadium redox flow battery is characterized by comprising a first conductive carbon fiber mesh film, wherein a first flexible graphite paper layer and a second flexible graphite paper layer are respectively arranged on two sides of the first conductive carbon fiber mesh film through a conductive composite adhesive, a second conductive carbon fiber mesh film is arranged on the outer side of the second flexible graphite paper layer through the conductive composite adhesive, and a third flexible graphite paper layer is arranged on the outer side of the second conductive carbon fiber mesh film through the conductive composite adhesive.

7. The all-vanadium flow battery bipolar plate according to claim 6, further comprising a third conductive carbon fiber mesh film, a fourth flexible graphite paper layer and a fourth conductive carbon fiber mesh film, wherein the third conductive carbon fiber mesh film is arranged on the outer side of the third flexible graphite paper layer through a conductive composite adhesive, the fourth flexible graphite paper layer is arranged on the outer side of the third conductive carbon fiber mesh film through a conductive composite adhesive, and the fourth conductive carbon fiber mesh film is arranged on the outer side of the fourth flexible graphite paper layer through a conductive composite adhesive.

8. The all-vanadium flow battery bipolar plate of claim 7, further comprising a fifth flexible graphite paper layer, wherein the fourth conductive carbon fiber mesh membrane is externally provided with the fifth flexible graphite paper layer by a conductive composite adhesive.

9. The all-vanadium flow battery bipolar plate of claim 8, further comprising a fifth conductive carbon fiber mesh film disposed outside the fifth flexible graphite paper layer by a conductive composite adhesive.

10. The all-vanadium flow battery bipolar plate of claim 9, further comprising a sixth conductive carbon fiber mesh membrane and a sixth flexible graphene layer, wherein a sixth flexible graphite paper layer is disposed outside the fifth conductive carbon fiber mesh membrane through a conductive composite adhesive, and wherein the sixth conductive carbon fiber mesh membrane is disposed outside the sixth flexible graphite paper layer through a conductive composite adhesive.

Technical Field

The invention relates to an all-vanadium redox flow battery bipolar plate and a preparation method thereof.

Background

Generally, an all-vanadium redox flow battery (which may be referred to as a vanadium battery for short) is a novel pollution-free chemical energy storage battery, belongs to a redox flow battery, does not generate solid-state reaction, and has the advantages of good current conversion capability, flexible structural design, reasonable cost, simple operation and the like.

The main function of the double electrodes of the vanadium battery in the battery is to isolate positive and negative electrolytes and to conduct out reaction current. Therefore, the bipolar plate for the vanadium redox battery is required to have good conductivity and barrier property, and the electrolyte of the vanadium redox battery is in an acidic environment, so that the bipolar plate is required to have good corrosion resistance. In the past research, metal bipolar plates, graphite bipolar plates, conductive composite bipolar plates and the like are tried, and different advantages and disadvantages of various current collectors are found in the process of long-term use.

The metal bipolar plate has good conductivity but poor corrosion resistance, and the utilization rate of the metal bipolar plate is not high due to the high price after the surface coating modification is carried out. The graphite bipolar plate has good conductivity, the corrosion resistance is improved after the corrosion-resistant material and the modification index process are added, but the continuous performance is poor, the thickness of the graphite bipolar plate is generally increased when the graphite bipolar plate is used for improving the mechanical performance, however, the cost of the graphite bipolar plate is expensive, but at present, a part of research institutions still use the graphite bipolar plate in the vanadium battery. The composite bipolar plate has the advantages of good mechanical property, thin thickness and the like, and is the most commonly used bipolar plate at present.

However, the composite bipolar plate has the greatest defect that the conductivity is not as good as that of a metal bipolar plate and a graphite plate, so that the improvement of the conductivity becomes a hotspot and difficulty of research.

Disclosure of Invention

In view of the above problems in the prior art, the main object of the present invention is to provide an all-vanadium redox flow battery bipolar plate which is low in cost and simple in process, and the prepared all-vanadium redox flow battery bipolar plate has the characteristics of good electrical conductivity and corrosion resistance, and also has the advantages of uniform thickness and good sealing performance.

The technical scheme of the invention is as follows:

a preparation method of an all-vanadium flow battery bipolar plate comprises the following steps: coating conductive composite adhesive on the surfaces of two sides of the conductive carbon fiber, attaching flexible graphite paper on the surfaces of the two sides of the conductive carbon fiber through the conductive composite adhesive, repeating the steps to form different thicknesses, and then putting the conductive carbon fiber into a flat plate hot press for hot pressing and curing to prepare the all-vanadium redox flow battery bipolar plate.

The conductive carbon fiber is JD-10 type conductive carbon fiber.

The preparation method of the conductive composite adhesive comprises the following steps: adding 55-65% by mass of aqueous polytetrafluoroethylene emulsion into a reaction kettle, adding 15-25% by mass of conductive carbon fiber short and short fibers for heating polymerization, adding 2.5-7% by mass of adhesion promoter (TPU) into the reaction kettle when the temperature is increased to 80 ℃, continuing heating the reaction kettle, stopping heating when the temperature is increased to 360 ℃, and cooling to normal temperature to prepare the aqueous conductive composite adhesive.

In the preparation method of the conductive composite adhesive, 2.5-7% by mass of an adhesion promoter is added when the temperature rises to 80 ℃ to continuously heat a reaction kettle piece, 3% by mass of adhesion promoter emulsion is added into the reaction kettle once when the temperature rises to 80 ℃ along with the rise of the temperature, and the heating of the reaction kettle is stopped when the temperature rises to 360 ℃.

The preparation method of the flexible graphite paper comprises the following steps: and uniformly spraying the aqueous conductive composite adhesive on two sides of the conductive carbon fibers, uniformly spraying expanded graphite powder in an expanded graphite powder bin, and rolling by using a calendering roller to form the flexible graphite paper.

The utility model provides an all-vanadium redox flow battery bipolar plate, includes first conductive carbon fiber mesh membrane, the both sides of first conductive carbon fiber mesh membrane set up first flexible graphite paper layer and second flexible graphite paper layer through electrically conductive compound adhesive respectively, the second flexible graphite paper layer outside sets up second conductive carbon fiber mesh membrane through electrically conductive compound adhesive, the second conductive carbon fiber mesh membrane outside sets up the third flexible graphite paper layer through electrically conductive compound adhesive.

The flexible carbon fiber net-shaped film is characterized by further comprising a third conductive carbon fiber net-shaped film, a fourth flexible graphite paper layer and a fourth conductive carbon fiber net-shaped film, wherein the third conductive carbon fiber net-shaped film is arranged on the outer side of the third flexible graphite paper layer through a conductive composite adhesive, the fourth flexible graphite paper layer is arranged on the outer side of the third conductive carbon fiber net-shaped film through a conductive composite adhesive, and the fourth conductive carbon fiber net-shaped film is arranged on the outer side of the fourth flexible graphite paper layer through a conductive composite adhesive.

The fourth conductive carbon fiber mesh film is arranged on the outer side of the fourth conductive carbon fiber mesh film through a conductive composite adhesive.

The flexible graphite paper is characterized by further comprising a fifth conductive carbon fiber mesh film, wherein the fifth conductive carbon fiber mesh film is arranged on the outer side of the fifth flexible graphite paper layer through a conductive composite adhesive.

The multifunctional conductive carbon fiber net-shaped film is characterized by further comprising a sixth conductive carbon fiber net-shaped film and a sixth flexible graphene layer, wherein a sixth flexible graphite paper layer is arranged on the outer side of the fifth conductive carbon fiber net-shaped film through a conductive composite adhesive, and the sixth conductive carbon fiber net-shaped film is arranged on the outer side of the sixth flexible graphite paper layer through the conductive composite adhesive.

The invention has the following advantages and beneficial effects: the preparation method of the bipolar plate of the all-vanadium redox flow battery has the characteristics of simple process, low cost and suitability for large-scale industrial production; in addition, the all-vanadium redox flow battery bipolar plate prepared by the preparation method has the characteristics of good conductivity and corrosion resistance, and also has the advantages of uniform thickness and good sealing performance.

Drawings

Fig. 1 is a schematic cross-sectional structural diagram of an all-vanadium redox flow battery bipolar plate provided in embodiment 1 of the present invention.

Fig. 2 is a schematic cross-sectional structural diagram of an all-vanadium redox flow battery bipolar plate provided in embodiment 2 of the present invention.

Fig. 3 is a schematic cross-sectional structural diagram of an all-vanadium redox flow battery bipolar plate provided in embodiment 3 of the present invention.

Fig. 4 is a schematic cross-sectional structural diagram of an all-vanadium redox flow battery bipolar plate provided in embodiment 4 of the present invention.

Fig. 5 is a schematic cross-sectional structural diagram of an all-vanadium redox flow battery bipolar plate provided in embodiment 5 of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. The components of embodiments of the present invention generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations. Thus, the following detailed description of the embodiments of the present invention, presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplicity of description, but do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the present invention, it should also be noted that, unless otherwise explicitly specified or limited, the terms "disposed," "mounted," "connected," and "connected" are to be construed broadly and may, for example, be fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

The invention will be further described with reference to the drawings and specific examples.