WO2019144751A1 - Liquid metal fuel cell - Google Patents

Abstract

Provided is a liquid metal fuel cell, comprising a body formed by assembling a cathode flow field plate (10), a gas cathode (3), an electrolyte membrane (9), and an anode flow field plate (11) in sequence. An oxidant (13) is injected into the cavity between the cathode flow field plate (11) and the gas cathode (3), and a fuel is injected into the cavity between the anode flow field plate (11) and the electrolyte membrane (9); the fuel is liquid metal. The present invention has the characteristics that metal is molten to flow when the working temperature of the cell is higher than the melting point of the fuel and the product metal hydroxide is also in a liquid state and flows after absorbing moisture and deliquescing; in addition, in the discharging mode of the reaction product, the staggered separation of the liquid and the gas in space is implemented due to the difference between the capillary forces of the liquid and gas in the pores of a hydrophobic gas cathode; the gas-liquid contact effective reaction area is increased, and channels are not blocked.

Description

Liquid metal fuel cell Technical field

The invention relates to the technical field of fuel cells, and in particular to a liquid metal fuel cell.

Background technique

With the increasing demand for energy from human activities, since the beginning of the 21st century, energy crisis and environmental issues have become the two major concerns of the world. Energy consumption is mainly in the transportation sector and power generation. Therefore, in order to realize the large-scale promotion and application of electric vehicles, it is necessary to carry out innovative research in the field of power batteries, and develop new power batteries with high power density, high energy density, high safety and low cost, and ensure their use as vehicle power. Has good operability.

Hydrogen-based hydrogen fuel cells have many advantages such as compact structure, flexible installation, fast load response, and no environmental pollution. The composition principle is similar to that of a general battery. As shown in FIG. 1, the single cell is composed of a cathode flow field plate 10, an air cathode 3, an electrolyte membrane layer 9, an anode 4, an anode flow field plate 11, and the like. The difference is that the active material of the general battery is stored inside the battery, thus limiting the battery capacity and posing a certain safety hazard. The hydrogen fuel cell is only a discharge device, and its active material is stored in an external storage tank of the battery. When the battery is in operation, the external supply system continuously supplies the oxidant (oxygen or air) and fuel (hydrogen) to the air cathode and the fuel anode of the battery through the cathode flow field plate and the anode flow field plate, respectively. In principle, as long as the fuel and oxidant are continuously input and the reaction products are continuously eliminated, the fuel cell can continuously generate electricity.

However, the shortcomings of hydrogen fuel cells are also very obvious, mainly:

(1) Source and production of hydrogen: Electrolytic hydrogen production from water and use it as an automobile fuel is technically difficult to use because of the high energy consumption and low energy conversion efficiency of electrolysis from water; from coal, oil and natural gas. The production of hydrogen by cracking requires consumption of limited fossil energy and CO _{2 production} , which is contrary to the original intention of hydrogen energy and does not meet the development direction of new energy in the future.

(2) Hydrogen storage technology: The hydrogen fuel of FCV is mainly compressed hydrogen. It is necessary to install a large-volume high-pressure gas cylinder on the vehicle, the weight of which is >100kg, but the filling amount is only about 3kg per time; The pressure is high and the danger of explosion is everywhere. The weight of the high pressure cylinder loses the practical value of the high specific energy properties of hydrogen.

(3) Hydrogen station infrastructure investment is large and difficult to popularize: At present, there are only about 100 global hydrogen refueling stations, which are still in the stage of demonstration and promotion.

In addition, there is a big misunderstanding that the hydrogen on the earth is inexhaustible and inexhaustible. Hydrogen is a trace natural existence on the earth, and there is no collection value. The low-energy hydrogen in seawater can only consume energy. It can be used as a fuel by reducing it to hydrogen. Therefore, hydrogen is not an ideal material in fuel cells as an energy carrier. Select an energy carrier that is easy to electrolyze, has high energy conversion efficiency, is safe, easy to store and transport, and has a small investment in fueling facilities. The practical use of the battery is of practical significance.

The fuels used in the existing fuel cell technology to replace hydrogen are mainly methanol, ethanol, methane and some hydrocarbons. Although the hydrogen production, storage and use problems are alleviated, there are CO ₂ emissions during use; and these materials Most of them are derived from fossil energy such as oil and coal. There are still some technical bottlenecks in large-scale applications.

Metals are a class of reducing agents similar to hydrogen. They are paired with oxidants (such as oxygen, sulfur, hydrogen peroxide, etc.) in an electrochemical reaction to convert their chemical energy into electrical energy in the form of electrons. In recent years, the application of metal air battery technology with metal as reducing agent and oxygen as oxidant has attracted widespread attention, such as lithium-oxygen battery, aluminum air battery, zinc-air battery, etc. Its working principle is similar to that of general battery, and anode reactant reduction The agent is a metal and the cathode reactant oxidant is oxygen in the air. The basic structural principle is shown in Fig. 2. The insulated porous membrane 1 and the aqueous electrolyte 8 divide the battery into two parts, a metal anode 2 and a gas cathode 3. The battery is filled with a water-based electrolyte 8, wherein the gas cathode 3 is from inside to outside. The catalytic layer 5, the collector layer 6, and the hydrophobic gas permeable layer 7 are in this order. The metal of the anode 2 undergoes an oxidation reaction to release electron-generating metal cations, and the released electrons are transferred to the gas cathode through the external circuit, and the metal cations are stored in the aqueous electrolyte 8; the oxygen in the air passes through the hydrophobic layer and the collector layer. catalytic action of the catalyst layer was incorporated in the electrolyte and the electrons participating in the formation of water in OH ^- ions, to complete the reduction reaction of oxygen, OH ^- ions into the aqueous electrolyte solution 8. The electrode reaction is:

Anode: M→M ⁿ⁺ +ne ^-

Cathode: O ₂ +2H ₂ O+4e ^- →4OH ^-

Total reaction: 4M+nO ₂ +2nH ₂ O→4M(OH) _n (M represents a metal atom, and n represents a metal ion valence.)

As a power generation device, the metal air battery only needs to maintain the supply of metal and air, that is, sustainable power generation, and the reaction product is a metal hydroxide, which can realize metal regeneration through smelting technology, so that the metal material can be recycled. The metal air battery is used to complete the energy release of the metal material, and the metal regeneration technology completes the storage process of the energy in the metal material, and the metal material is recycled as an energy carrier. The energy storage process and the energy release process are completed in two separate systems, which greatly reduces the technical difficulty in each process, and makes the system more flexible in time and space by separating the two processes independently. In summary, metal air batteries have some advantages as fuel cells.

However, the existing literature confuses the concept of a metal air battery with a metal fuel cell. In fact, a metal air battery can only be called a semi-fuel battery because, on the one hand, the metal is a solid which is difficult to flow at normal temperature, and it is difficult to achieve continuous feeding. On the other hand, the alkaline product after discharge is stored in a large amount in the electrolyte inside the battery, so that the battery stack is bulky, the energy density is low, the safety hazard is large, and the electrode is extremely corrosive.

technical problem

1. Hydrogen fuel cells have the following obvious disadvantages:

(1) Source and production of hydrogen: Electrolytic hydrogen production from water and use it as an automobile fuel is technically difficult to use because of the high energy consumption and low energy conversion efficiency of electrolysis from water; from coal, oil and natural gas. The production of hydrogen by cracking requires consumption of limited fossil energy and CO _{2 production} , which is contrary to the original intention of hydrogen energy and does not meet the development direction of new energy in the future.

(2) Hydrogen storage technology: The hydrogen fuel of FCV is mainly compressed hydrogen. It is necessary to install a large-volume high-pressure gas cylinder on the vehicle, the weight of which is >100kg, but the filling amount is only about 3kg per time; The pressure is high and the danger of explosion is everywhere. The weight of the high pressure cylinder loses the practical value of the high specific energy properties of hydrogen.

(3) Hydrogen station infrastructure investment is large and difficult to popularize: At present, there are only about 100 global hydrogen refueling stations, which are still in the stage of demonstration and promotion.

(4) The hydrogen energy on the earth is not inexhaustible and inexhaustible. Hydrogen is naturally present in the earth and has no collection value. The low-energy hydrogen in seawater can only be reduced by consuming energy. Hydrogen can be used as a fuel.

Second, the metal air battery has the following technical disadvantages: on the one hand, the metal is a solid which is difficult to flow at normal temperature, it is difficult to achieve continuous feeding, and the continuous working performance is poor; on the other hand, the alkaline product after discharge is stored in a large amount in the interior of the battery. In the liquid, the battery stack is bulky, the energy density is low, the safety hazard is large, and the electrode is extremely corrosive.

Technical solution

Based on the deficiencies of the existing hydrogen fuel cell and metal air battery technologies, the present invention provides a liquid metal fuel cell to solve the problem of the presence of fuel hydrogen in a hydrogen fuel cell, and the difficulty in solid feeding of the metal air battery, the battery The problem of internal product and electrolyte retention.

In order to solve the above technical problems, the present invention is achieved by the following technical solutions:

A liquid metal fuel cell comprising a body assembled in sequence from a cathode flow field plate, a gas cathode, an electrolyte membrane and an anode flow field plate, wherein an oxidant is injected into a cavity between the cathode flow field plate and the gas cathode. The cavity between the anode flow field plate and the electrolyte membrane is filled with liquid metal; the operating temperature of the battery is higher than the freezing point of the liquid metal.

In a further aspect, the liquid metal comprises a metal element, a metal alloy, a metal mixture, and a metal compound.

Preferably, the metal element is a substance of lithium, sodium or potassium.

In a further aspect, the oxidant is a mixed gas containing oxygen and water, including humidified air and humidified oxygen.

In a further aspect, the electrolyte membrane is composed of one or more composites of a metal ion conductor glass ceramic electrolyte, a metal ion conductor polymer electrolyte, and a metal ion conductor gel electrolyte.

In a further aspect, the gas cathode is composed of a composite of a hydrophobic gas permeable layer and a catalytic layer, and the hydrophobic gas permeable layer, the catalytic layer and the electrolyte membrane are bonded to each other to form an integral body.

In a further aspect, the hydrophobic gas permeable layer is a porous structural layer composed of nickel, stainless steel or monel, and is obtained by hydrophobizing a polytetrafluoroethylene solution.

In a further aspect, the catalytic layer is a porous structure made by mixing and sintering at least one of porous carbon, porous nickel, MnO ₂ , Co ₃ O ₄ , and LaNiO with polytetrafluoroethylene.

In the preferred embodiment of the present invention, humidified oxygen or humidified air is selected as the oxidant, which can increase the output voltage of the battery and is environmentally friendly. In particular, the humidified air is inexhaustible and does not need to be stored, making the battery more environmentally friendly and safe. cheap.

Further, in the present invention, the oxidizing agent may also be selected from a liquid oxidizing agent.

When the liquid metal fuel cell of the present invention is in operation, the battery is first placed in a temperature environment where the temperature is higher than the freezing point of the liquid metal, so that the metal enters the cavity between the anode flow field plate and the electrolyte membrane from the outside in a molten state. In the body, and uniformly distributed to one side interface of the electrolyte membrane through the anode flow field plate; an oxidant (such as humidified air mixed by water and air) is injected into the cavity between the cathode flow field plate and the gas cathode, and then distributed to In the pores of the hydrophobic gas permeable layer in the gas cathode. The anode is formed by the metal having good electrical conductivity, and the electron ion is used to generate metal ions and free electrons. The free electrons pass through the anode current collector through the anode flow field plate to work on the external circuit load, and then pass through the cathode flow field plate and are hydrophobic. After the gas permeable layer enters the catalytic layer; at the same time, the metal ions directly pass through the electrolyte membrane to reach the interface between the electrolyte membrane and the catalytic layer. At the same time, the oxygen in the oxidant combines with the free electrons entering the anode and the water in the oxidant under the catalytic action of the catalytic layer to form OH ^- (total reaction: O ₂ + 2H ₂ O + 4e ^- = 4OH ^- ), anion OH ^- and cationic metal The ions combine to form a metal hydroxide on the "three-phase interface" composed of the catalytic layer, the electrolyte membrane, and the oxidant. Since the metal hydroxide has water-absorbing and deliquescent characteristics, once formed, it rapidly absorbs water in the oxidant to form droplets. As the reaction continues, the droplets gradually increase and increase, and ooze out from the large pores of the gas cathode hydrophobic gas permeable layer under the action of the pressing force and enter the cavity between the cathode flow field plate and the gas cathode. The residual air of the humidified air after the reaction in the chamber is purged to the outside of the battery. Among them, because the hydrophobic gas permeable layer in the gas cathode is hydrophobic, in the pores due to the capillary force, the metal hydroxide droplets can only flow out through the pores with less resistance and larger pore diameter; The resistance is small, so it is occupied by the oxidant, thus automatically forming a double channel of gas and liquid, so that the gas and liquid circulation are not blocked by each other and the effective reaction area is increased. This is a key innovation point of this technical solution. The existing hydrogen fuel cell structure is only suitable for fluid oxidants, reducing agents and mixed products which are both liquid or gaseous, and realizes integration of the existing hydrogen fuel cell structure into a metal fuel cell using metal as a reducing agent (fuel). The metal and its reaction products must be in a flowing liquid state.

Beneficial effect

The hydrophobic gas permeable layer of the present invention uses a porous structural layer composed of nickel, stainless steel or monel, and is obtained by hydrophobization treatment of a polytetrafluoroethylene solution, except that it can effectively permeate the gas and remove the electrolyte, because it has a larger The mechanical strength can effectively support the catalytic layer and the electrolyte layer, so that the electrolyte membrane can reduce the book, reduce the conduction resistance of the conductive ions, improve the output power of the battery, and further improve the safety of the battery.

The catalytic layer in the preferred embodiment of the present invention is a porous structure prepared by mixing and sintering at least one of porous carbon, porous nickel, MnO ₂ , Co ₃ O ₄ , and LaNiO with polytetrafluoroethylene, and the material cost thereof is low. In addition, due to the high operating temperature of the battery, the catalytic efficiency is high, and it is not necessary to use a precious metal (such as platinum or gold) as a catalyst, which can greatly reduce the cost of the battery.

The present invention uses liquid metal as a fuel for a battery, thereby circumventing the problems of fuel hydrogen gas of a hydrogen fuel cell, and the difficulty of solid feeding in the metal air battery, the product in the battery, and the retention of the electrolyte.

Like hydrogen, metal is a kind of energetic body with high energy density, but metal is easier to regenerate, easier to transport and store, and does not require high pressure tank packaging. Therefore, the battery of the invention operates at a temperature higher than the freezing point of the liquid metal, so that the liquid metal has fluidity above its freezing point temperature, and continuous feeding can be realized; at the same time, the basic structure of the hydrogen fuel cell is adopted by adding water and the like in the oxidant. The basic principle of metal air battery is effectively integrated to avoid some technical bottlenecks of existing metal air batteries, so that the structural advantages of hydrogen fuel cells and the electrochemical advantages of metal air batteries are fully exerted. For fuel cells, especially new energy electric vehicles. Development has a greater technological impetus.

The present invention is a technology that fully utilizes the meltability of a liquid metal fuel, the water-deliquessability of a product thereof, and its solubility in water, by designing a battery operating temperature to be higher than a freezing point of the liquid metal fuel and mixing water vapor in the oxidant. The method is such that the metal fuel is in a molten flowing liquid state, and the formed solid hydroxide absorbs water in the oxidant to form a flowable solution.

The invention utilizes the difference of capillary force between the liquid and the gas in the pores of the hydrophobic gas cathode in the way of discharging the reaction product, realizes the spatially interlaced separation of gas and liquid, and increases the effective reaction of gas-liquid contact. The area does not block the passages.

DRAWINGS

1 is a schematic structural view of a conventional hydrogen fuel cell,

2 is a schematic structural view of a conventional metal fuel cell,

Figure 3 is a schematic view of the structure of the present invention,

4 is a schematic structural diagram of a second embodiment (best embodiment) of the present invention,

FIG. 5 is a schematic structural diagram of Embodiment 3 of the present invention.

In the figure: 1-porous membrane, 2-metal anode, 3-gas cathode, 4-anode, 5-catalytic layer, 6-collector layer, 7-hydrophobic gas permeable layer, 8-electrolyte, 9-electrolyte membrane, 10 - Cathode flow field plate, 11-anode flow field plate, 12-liquid metal, 13-oxidant, 14-lithium, 15-sodium.

BEST MODE FOR CARRYING OUT THE INVENTION

As shown in FIG. 5, a liquid metal fuel cell is sequentially assembled from a cathode flow field plate 10, a gas cathode 3, an electrolyte membrane 9 and an anode flow field plate 11, wherein the gas cathode 3 comprises a hydrophobic gas permeable layer 7 The catalytic layer 5, the hydrophobic gas permeable layer 7, the catalytic layer 5 and the electrolyte membrane 9 are sequentially bonded to each other to form an integral body; the chamber between the cathode flow field plate 10 and the gas cathode 3 is filled with humidified air containing water vapor. The chamber between the anode flow field plate 11 and the electrolyte membrane 9 is filled with molten elemental sodium 15; the operating temperature of the battery is higher than 97.8 °C.

Further, the electrolyte membrane 9 is composed of one or a combination of a metal ion conductor glass ceramic electrolyte, a metal ion conductor polymer electrolyte, and a metal ion conductor gel electrolyte.

In a further embodiment, the hydrophobic gas permeable layer 7 is a porous structural layer composed of nickel, stainless steel or monel, and is obtained by hydrophobizing a polytetrafluoroethylene solution.

Further, the catalytic layer 5 is a porous structure made by mixing and sintering at least one of porous carbon, porous nickel, MnO ₂ , Co ₃ O ₄ , and LaNiO with polytetrafluoroethylene.

The melting point of elemental sodium is 97.8 ° C, so the working environment temperature of the battery is set higher than 97.8 ° C, and elemental sodium enters and is distributed to the interface of the electrolyte membrane 9 through the anode flow field plate 11 in a molten state; the water vapor is mixed with air. The humidified air enters through the cathode flow field plate 10 from the outside and is distributed into the pores of the hydrophobic gas permeable layer 7 in the gas cathode 3. Using elemental sodium metal having good conductive property constituting the anode collector, and since sodium has a negative power, the first loss of one e ^- generating Na ^+, wherein, e ^- an outer flow constituted by the sodium anode collector of the anode flow field plate 11 The circuit load is work, and then enters the catalytic layer 5 through the cathode flow field plate 10 and the hydrophobic gas permeable layer 7; at the same time, Na ⁺ directly passes through the electrolyte membrane 9 to reach the interface of the catalytic layer 5. At the same time, O ₂ in the humidified air obtains the emitted e ^- under the catalytic action of the catalytic layer 5, and combines with the water in the humidified air to form OH ^- (total reaction: O ₂ + 2H ₂ O + 4e ^- = 4OH ^- ), anion OH ^- and cation Na ⁺ combine to form NaOH on the "three-phase interface" composed of the catalytic layer 5, the electrolyte membrane 9, and the humidified air. Since NaOH has a water-absorbing deliquescent property, once formed, it rapidly absorbs water in the humidified air to form droplets. As the reaction continues, the droplets gradually increase and increase, and ooze out from the large pores of the hydrophobic gas permeable layer 7 under the action of the pressing force and enter the cavity between the cathode flow field plate and the gas cathode. The residual humidified air in the body is purged to the outside of the battery. Among them, because the pores of the hydrophobic gas permeable layer 7 are hydrophobic, in the pores due to the capillary force, the NaOH droplets can only flow out through the pores with less resistance and slightly larger pore diameter, and the small pores are increased due to the small gas resistance. The humid air occupies, thus automatically forming a gas and a liquid double channel, so that the gas and liquid circulation are not blocked by each other and the effective reaction area is increased.

Embodiments of the invention

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

Embodiment 1:

As shown in FIG. 3, a liquid metal fuel cell includes a body assembled in order from a cathode flow field plate 10, a gas cathode 3, an electrolyte membrane 9, and an anode flow field plate 11, the cathode flow field plate 10 and a gas. An oxidant 13 is injected into the cavity between the cathodes 3, and a liquid metal 12 is injected into the cavity between the anode flow field plate 11 and the electrolyte membrane 9; the operating temperature of the battery is higher than the freezing point of the liquid metal 12.

In a further aspect, the liquid metal comprises a metal element, a metal alloy, a metal mixture, and a metal compound.

Preferably, the metal element is a substance of lithium, sodium or potassium.

In a further aspect, the oxidant 13 is a mixed gas containing oxygen and water, including humidified air and humidified oxygen.

Further, the electrolyte membrane 9 is composed of one or a combination of a metal ion conductor glass ceramic electrolyte, a metal ion conductor polymer electrolyte, and a metal ion conductor gel electrolyte.

Further, the gas cathode 3 is composed of a composite of a hydrophobic gas permeable layer 7 and a catalytic layer 5, and the hydrophobic gas permeable layer 7, the catalytic layer 5 and the electrolyte membrane 9 are bonded to each other to form an integral body.

In a further embodiment, the hydrophobic gas permeable layer 7 is a porous structural layer composed of nickel, stainless steel or monel, and is obtained by hydrophobizing a polytetrafluoroethylene solution.

Further, the catalytic layer 5 is a porous structure made by mixing and sintering at least one of porous carbon, porous nickel, MnO ₂ , Co ₃ O ₄ , and LaNiO with polytetrafluoroethylene.

In a further aspect, the operating temperature of the liquid metal fuel cell is not lower than the melting point of the fuel.

Embodiment 2:

As shown in FIG. 4, a liquid metal fuel cell comprising a gas flow cathode 3, an electrolyte membrane 9 and an anode flow field plate 11 which are sequentially composed of a cathode flow field plate 10, a hydrophobic gas permeable layer 7 and a catalytic layer 5, are assembled. The body of the hydrophobic gas permeable layer 7, the catalytic layer 5 and the electrolyte membrane 9 are integrally bonded to each other; the chamber between the cathode flow field plate 10 and the gas cathode 3 is filled with humidified oxygen containing water vapor and oxygen. The chamber between the anode flow field plate 11 and the electrolyte membrane 9 is filled with lithium 14 in a molten fluid state; the operating temperature of the battery is higher than 181 °C.

The electrolyte membrane 9 is composed of one or a combination of a metal ion conductor glass ceramic electrolyte, a metal ion conductor polymer electrolyte, and a metal ion conductor gel electrolyte.

The hydrophobic gas permeable layer 7 is a porous structural layer composed of nickel, stainless steel or monel and is obtained by hydrophobizing a polytetrafluoroethylene solution.

The catalytic layer 5 is a porous structure made by mixing and sintering at least one of porous carbon, porous nickel, MnO ₂ , Co ₃ O ₄ , and LaNiO with polytetrafluoroethylene.

The working environment temperature of the battery is set to be higher than 181 ° C, and elemental lithium enters and is distributed to the interface of the electrolyte membrane 9 through the anode flow field plate 11 from the outside in a molten fluid state; humidified oxygen formed by mixing water vapor and oxygen is passed through the outside. The cathode flow field plate 10 enters and is distributed into the pores of the hydrophobic gas permeable layer 7 in the gas cathode 3. Use of elemental lithium metal having good conductive property constituting the anode collector, since the lithium and having a negative power, a first loss e ^- generated Li ^+, wherein, e ^- the lithium anode by the collector to the configuration of the outer plate 11 through the anode flow field The circuit load is work, and then enters the catalytic layer 5 through the cathode flow field plate 10 and the hydrophobic gas permeable layer 7; at the same time, Li ⁺ directly passes through the electrolyte membrane 9 to reach the interface of the catalytic layer 5. At the same time, O ₂ in the humidified oxygen gas obtains the emitted e ^- under the catalytic action of the catalytic layer 5, and combines with the water in the humidified oxygen to form OH ^- (total reaction: O ₂ + 2H ₂ O + 4 e ^- =4OH ^- ), the anion OH ^- combines with the cation Li ⁺ to form a LiOH on the "three-phase interface" composed of the catalytic layer 5, the electrolyte membrane 9, and the humidified oxygen. Since LiOH has water absorbing and deliquescent properties, once formed, it rapidly absorbs water in the humidified oxygen to form droplets. As the reaction continues, the droplets gradually increase and increase, and ooze out from the large pores of the hydrophobic gas permeable layer 7 under the action of the pressing force and enter the cavity between the cathode flow field plate and the gas cathode. The reacted humidified oxygen residual gas in the body is purged to the outside of the battery. Among them, because the pores of the hydrophobic gas permeable layer 7 are hydrophobic, the LiOH droplets can only flow out through the pores with less resistance and slightly larger pore size due to the capillary force in the pores, and the small pores are increased due to the small gas resistance. Wet oxygen occupies, so that the gas and liquid channels are automatically formed, so that the gas and liquid flows are not blocked by each other and the effective reaction area is increased.

The above described embodiments are merely illustrative of the preferred embodiments of the present invention, and are not intended to limit the scope of the present invention, and various modifications of the technical solutions of the present invention will be made by those skilled in the art without departing from the spirit of the invention. And improvements are intended to fall within the scope of the protection as defined by the appended claims.

Industrial applicability

The invention utilizes the melt fluidity of the liquid metal in the working temperature environment of the battery above the freezing point and the water deliquescent property of the product metal hydroxide in the humidifying environment, and the electrode structure of the traditional hydrogen fuel cell and the electrochemical principle of the metal air battery. The creative integration, complementing each other, constitutes a new liquid metal fuel cell system, which can be combined with traditional technologies and processes in industrial manufacturing implementation, greatly reducing the difficulty of industrial implementation. The invention is mainly used in the field of power battery and large-scale energy storage, and the advantages of high safety, high power density, low cost and long life are likely to bring greater technological progress to the field and promote the development of new energy in the world. It has important practical significance and industrial applicability.

Claims (8)

A liquid metal fuel cell comprising a body assembled in turn from a cathode flow field plate (10), a gas cathode (3), an electrolyte membrane (9) and an anode flow field plate (11), characterized in that: the cathode An oxidant (13) is injected into the cavity between the flow field plate (10) and the gas cathode (3); a liquid metal is injected into the cavity between the anode flow field plate (11) and the electrolyte membrane (9) (12) The operating temperature of the battery is higher than the freezing point of the liquid metal (12). A liquid metal fuel cell according to claim 1, wherein said liquid metal (12) comprises a metal element, a metal alloy, a metal mixture and a metal compound. A liquid metal fuel cell according to claim 2, wherein said metal element is a simple substance of lithium, sodium or potassium. A liquid metal fuel cell according to claim 1, wherein said oxidizing agent (13) is a mixed gas containing oxygen and water, and includes humidified air and humidified oxygen. A liquid metal fuel cell according to claim 1, wherein said electrolyte membrane (9) is one of a metal ion conductor glass ceramic electrolyte, a metal ion conductor polymer electrolyte, and a metal ion conductor gel electrolyte. Or two or more composite compositions. A liquid metal fuel cell according to claim 1, wherein said gas cathode (3) is composed of a hydrophobic gas permeable layer (7) and a catalytic layer (5), said hydrophobic gas permeable layer (7) The catalytic layer (5) and the electrolyte membrane (9) are bonded to each other to form an integral body. A liquid metal fuel cell according to claim 6, wherein said hydrophobic gas permeable layer (7) is a porous structural layer composed of nickel, stainless steel or monel, and is hydrophobized by a polytetrafluoroethylene solution. Process the income. A liquid metal fuel cell according to claim 6, wherein said catalytic layer (5) is composed of at least one of porous carbon, porous nickel, MnO ₂ , Co ₃ O ₄ , and LaNiO A porous structure made by mixing and sintering fluoroethylene.