CN1549371A - Mounting structure for electric generator of boron compound fuel cell - Google Patents

Abstract

The present invention belongs to a mounting structure for generator of boron compound fuel cell. In said generator the electrochemical reaction of aqueous solution of B4H- and air can be used for making power generation. It is characterized by that single generator or combination of several generators can be mounted obliquely toward the direction of negative electrode according to a certain angle of theta (10-30 deg.). When it is used for making power generation, in the electrochemical reaction of fuel and air the generator can not be influenced by hydrogen gas produced by negative reaction, and the power generation efficiency of the generator can be raised.

Description

Mounting structure of generator of boron compound fuel cell

Technical Field

The present invention pertains to an externally supplied aqueous solution state BH^- ₄Fuel cell for generating electricity by electrochemical reaction with airIn particular to a mounting structure of a generator of a boron compound fuel cell.

Background

Fuel cells have been disclosed which convert energy in fuel directly into electric energy, and these fuel cells generally have an anode and a cathode disposed on both sides of a polymer electrolyte, and perform an electrochemical oxidation reaction of hydrogen in the fuel on the anode (an oxidation electrode or a fuel electrode) and an electrochemical reduction reaction of oxygen on the cathode (a reduction electrode or an air electrode) to generate electricity by electrons. The hydrogen gas supplied to these fuel cells is liquefied natural gas, liquefied petroleum gas, methanol (CH)₃Hydrocarbon series (CH series) fuels such as OH), gasoline and the like are subjected to a desulfonation process, a reforming reaction and hydrogen refining in a reformer, and only hydrogen (H) is subjected to₂) Refining the slurry to use it in a gaseous state or using BH in a solid state^- ₄And the fuel is converted into an aqueous solution state and directly used as a fuel in a BFC mode. The BFC fuel cell does not use a reformer because BH in an aqueous solution state is directly supplied to the anode of the power generation device^- ₄In this way, the reforming reaction is generated on the electrode, so that a reformer is not required, which has an advantage that the entire system can be simplified.

As shown in fig. 1 and 2, a known BFC fuel cell will be briefly described:

the fuel cell 1 includes a power generator 10 and a fueltank 2, a supply pipe 3 and a fuel recovery pipe 4 are connected to anodes of the fuel tank 2 and the power generator 10, and a fuel pump 4 is mounted on the supply pipe 3. An air supply pipe 6, an air exhaust pipe 7 and a power transmission line 9 are arranged on the cathode of the generator 10, and an air pump 8 is arranged on the air supply pipe 6. In general, the power generator 10 is a single cell or a combination of a plurality of single cells, and in the case of a single cell, the anode 22 and the cathode 23, which diffuse gas on both sides of the electrolyte membrane 21, are combined together to form a membrane-electrode assembly 24, a separator 25, with passages 31 for fuel gas and air containing oxygen left between the anode 22 and the cathode 23, and current collecting plates 26 are respectively mounted on both sides of the separator to constitute collectors of the anode 22 and the cathode 23. When the switch of the generator 10 is turned on, the fuel stored in the fuel tank 2 is pumped out from the fuel pump 5 to be supplied to the anode of the generator 10 through the supply pipe 3, and at the same time, the air pump 8 is activated to supply air to the cathode of the generator 10 through the air supply pipe 6. Fuel flows between the polymer electrolyte membranes 21 in the power generator 10, hydrogen undergoes an electrochemical oxidation reaction at the anode, oxygen undergoes an electrochemical reduction reaction at the cathode, electrons generated at this time move to generate electricity, and the generated electricity is collected by the current collecting plate to be used as energy.

The reaction equation is:

anode: E₀＝1.24V

cathode: E₀＝0.4V

the general formula is as follows: E₀＝1.64V

in the above reaction, BH is^- ₄Converting into a stable solution, adding a certain amount of sodium (Na) to mix, so that a negative reaction occurs at the anode, and the product is 2H₂O+NaBH₄+4H₂The hydrogen gas produced at this time is circulated inside the generator 10 together with the fuel. However, hydrogen gas generated by the negative reaction at the anode of the power generator 10 is attached to the surfaces of the electrolyte membrane 21 and the anode 22 in a large amount in the form of bubbles. In this way, the active reaction of the fuel and air is prevented by the electrolyte membrane 21, resulting in a decrease in the power generation efficiency.

Disclosure of Invention

In order to solve the above problems, it is an object of the present invention to provide a structure for mounting a power generator of a boron compound fuel cell capable of preventing hydrogen bubbles generated in a negative reaction from adhering to an electrolyte membrane and an anode, and actively electrochemically reacting fuel and air to improve power generation efficiency.

The technical scheme of the invention is as follows: the installation structure of power generator of boron compound fuel cell includes anode set on one side of electrolyte membrane and cathode set on the other side, and the anode, cathode and electrolyte membrane are formed into membrane-electrode assembly. Current collecting plates capable of collecting electricity generated in the electrochemical reaction are provided on both sides of the membrane-electrode assembly. The generator is arranged towards the cathode direction according to a certain inclination angle theta (10 degrees to 30 degrees),and the channel formed by the separator is inclined towards the cathode direction according to the same angle, so that the hydrogen is circulated in a state of falling from the inner side surface of the anode.

Drawings

FIG. 1 is a schematic view of a known fuel cell

FIG. 2 is a longitudinal sectional view of a power generator structure of a known fuel cell

FIG. 3 is a longitudinal view of a mounting structure of a power generator using a boron compound fuel cell of the present invention

A cross-sectional view.

FIG. 4 is a front view of another embodiment of the present invention

FIG. 5 is a front view of the 3 rd embodiment of the present invention

Wherein:

1 fuel cell 2 fuel tank 3 feed pipe

4 fuel recovery pipe 5 fuel pump 6 air supply pipe

7 exhaust pipe 8 air pump 9 power transmission line

10 generator 21 electrolyte membrane 22 anode

23 cathode 24 membrane-electrode assembly 25 separator

26 collector plate 31 channel 100 generator

101 electrolyte membrane 102 anode 103 cathode plate

104 Membrane-electrode Assembly 105 separator 105a channel hole

106 channel 201 bolt of collector plate 107

Detailed Description

The invention is described in detail below with reference to the attached drawing figures: as shown in fig. 3, the power generator 100 includes an electrolyte membrane 101 having a certain thickness (5-10mm), an anode 102 and a cathode 103, which are combined to form a membrane-electrode assembly 104, wherein separators 105 capable of forming fuel and air flow passages are respectively installed at both sides of the membrane-electrode assembly 104, and collector plates 106 are respectively closely installed at both sides of the separators 105. The power generator 100 constituted by the above-mentioned components is installed in a state of being inclined at a certain angle θ (10 to 30 °) toward the cathode 103 so that the hydrogen gas flows along the inside of the inclined passage 107 and circulates in a state of falling from the inside of the anode 102. The electrolyte membrane 101 is an ion exchange membrane (commercially available) made of a polymer material, and has an effect of preventing contact between oxygen and hydrogen while performing ion conduction. The anode 102 and the cathode 103 are supports that support platinum (Pt) catalyst layers, and porous carbonized paper or carbonized cloth is bonded on both sides of the electrolyte membrane 101. The separator 105 is a dense carbon plate, the inner side faces are closely adhered to the anode 102 and the cathode 103, and channel holes 105a that enable the fuel and hydrogen to flow are formed. The collector plate 106 should be conductive and corrosive and not weaken the hydrogen gas, particularly using aluminum, copper, or the like, as desired.

Fig. 4 shows another embodiment of the present invention, in which a single generator 100 of a fuel cell (C) has the same structure as the generator 10 shown in fig. 3, and a plurality of generators 100 are stacked and fixed by bolts 201 to form a stack (S) of cells (S) arranged at a certain inclination angle θ (10-30 °)

Fig. 5 shows a 3 rd embodiment of the present invention, in which the single generator 100 of the fuelcell has the same structure as the generator 10 shown in fig. 3, and in this embodiment, each generator 100 is installed at a certain inclination angle θ (10-30 °), and then a plurality of generators are fixed by bolts 201 to form a cell stack (S is pointed).

The working process and the effect of the invention are as follows: when the machine is in operation, BH in the state of an aqueous solution is supplied to a channel 107 formed between the anode 102 and the separator 105 of the generator 100^- ₄While supplying air to a passage 107 formed between the cathode 103 and the separator 105, BH being supplied^- ₄And air are separated by the electrolyte membrane 101, flow along the passage 107, diffuse in front of the anode 102 of the membrane-electrode assembly 104 to perform electrochemical oxidation of hydrogen, while air diffuse in front of the cathode 103 of the membrane-electrode assembly 104 to perform electrochemical reduction of oxygen, at which time electricity is generated due to the movement of generated electrons, and the generated electricity is collected on the collector plate 106 to be used as an energy source. BH in aqueous solution^- ₄Electrochemical reaction is performed on the anode 102Hydrogen gas is generated due to the negative reaction of the additive Na. Since the power generator 100 of the present invention is installed in a state of being inclined toward the cathode 103 at a certain angle θ (10 to 30 °), the generated hydrogen gas falls from the anode and flows along the inner side surfaces of the passage holes 105a of the separator 105, so that the reaction of the fuel and the air is hardly affected by the hydrogen gas, and the reaction can be actively performed, thereby improving the power generation efficiency.

Claims (3)

1. A structure for mounting a generator of a boron compound fuel cell, comprising an electrolyte membrane, an anode provided on one side of the electrolyte membrane, and a cathode provided on the other side thereof, wherein BH in an aqueous solution is supplied to the anode^- ₄Supplying air to the cathode, BH^- ₄Generating electric energy by electrochemical reaction with air, and forming a membrane-electrode assembly by the electrolyte membrane, the anode and the cathodeTo both sides of the membrane-electrode assembly, BH forming fuel (aqueous solution state) is attached^- ₄) And a separator of air flow channel, and current collector plates arranged on both sides of the separator, wherein the generator composed of membrane-electrode assembly, separator and current collector plates is installed in a manner of inclining to the cathode direction at a certain angle theta (10-30 deg.).

2. The structure of claim 1, wherein the plurality of generators are assembled and fixed by bolts and then installed in the cathode direction at an angle θ (10-30 °).

3. The structure of claim 1, wherein the plurality of generators are installed in such a manner that each generator is inclined in the direction of the cathode at a predetermined angle θ (10 to 30 °), and then the plurality of generators are fixed by bolts.

Images