A method for hydrogen-assisted rechargeable batteries for hydrogen storage and production

Abstract

This invention discloses a hydrogen-assisted rechargeable battery method for hydrogen storage and production, belonging to the field of hydrogen energy storage and electrochemical energy storage technology. The method includes four core steps: battery assembly, circulating electrolyte supply, charging for hydrogen storage, and discharging for hydrogen production. During charging, hydrogen-containing gas is introduced into the cathode, where a hydroxide reaction occurs, and metal ion reduction and deposition occur at the anode, storing hydrogen energy as a metallic element in a solid state under normal pressure. During discharging, a metal oxidation and dissolution reaction occurs at the anode, and a hydrogen evolution reaction occurs at the cathode, generating hydrogen gas in situ and releasing hydrogen energy on demand. This invention eliminates the oxygen evolution reaction of traditional water electrolysis, using hydroxide coupled with metal oxidation-reduction to achieve hydrogen energy storage and release. It offers high storage safety, low reaction overpotential, high energy efficiency, and good cycle reversibility, solving the problems of poor safety, high energy consumption, and low energy efficiency in existing hydrogen storage technologies. It can be widely applied to renewable energy hydrogen production, large-scale hydrogen energy storage, and distributed hydrogen energy supply scenarios.

Description

Technical Field

[0001] This invention belongs to the field of hydrogen energy storage and electrochemical energy storage technology, specifically relating to a method for hydrogen-assisted rechargeable batteries for hydrogen storage and production. Background Technology

[0002] Hydrogen energy, as a clean, efficient, and renewable secondary energy carrier, is one of the core technologies for achieving sustainable energy development. However, its large-scale commercial application has always been constrained by bottlenecks in storage safety, energy efficiency, and economic viability.

[0003] Currently, mainstream hydrogen storage solutions all have significant drawbacks: high-pressure gaseous hydrogen storage relies on heavy pressure-resistant containers, posing safety hazards such as leakage and explosion, and has low volumetric energy density, resulting in high transportation and storage costs; cryogenic liquid hydrogen storage requires cooling hydrogen to -253°C, with extremely high energy consumption in the liquefaction process and complex and expensive supporting systems, making it only suitable for special scenarios such as aerospace; solid-state metal hydrogen storage and organic liquid hydrogen storage solutions generally suffer from low reversible hydrogen storage capacity, harsh hydrogen absorption and desorption conditions (requiring high temperature / high pressure environments), and poor cycle stability, making them unsuitable for large-scale, routine hydrogen storage needs.

[0004] In the field of electrochemical hydrogen storage and on-demand hydrogen production, water electrolysis technology is currently the mainstream approach, encompassing sub-fields such as proton exchange membrane electrolysis, alkaline water electrolysis, and solid oxide electrolysis. However, this technology suffers from fundamental technical drawbacks: the kinetics of the oxygen evolution reaction (OER) at the anodic end of water electrolysis are slow, requiring extremely high overpotentials to drive the reaction, resulting in high energy consumption and low energy conversion efficiency for the entire hydrogen production system; simultaneously, the OER relies on precious metal catalysts such as iridium and ruthenium, along with core components like proton exchange membranes, significantly increasing the system's equipment and maintenance costs, making large-scale application difficult.

[0005] In addition, existing electrochemical hydrogen storage systems generally suffer from poor reversibility of cycling, numerous side reactions, and the inability to achieve closed-loop circulation of the medium, making it impossible to simultaneously achieve the dual goals of "safe hydrogen storage at atmospheric pressure" and "low-energy on-demand hydrogen production". Summary of the Invention

[0006] The purpose of this invention is to overcome the shortcomings of existing technologies. It addresses the problems of poor safety, high energy consumption, and low volumetric energy density of existing physical hydrogen storage methods, as well as the slow kinetics of the oxygen evolution reaction at the anode, high system energy consumption, low energy efficiency, and high cost of traditional water electrolysis hydrogen production technology. The invention provides a hydrogen-assisted rechargeable battery method for hydrogen storage and production. By coupling the hydrogen oxidation reaction with the metal redox reaction, it achieves safe storage of hydrogen energy at atmospheric pressure and low-energy on-demand production.

[0007] To solve the above-mentioned technical problems, the present invention provides the following technical solution:

[0008] A method for a hydrogen-assisted rechargeable battery for hydrogen storage and production includes the following steps:

[0009] S1: Battery Assembly: Set up a cathode chamber and an anode chamber that are isolated from each other in the reactor. Install a gas diffusion electrode or membrane electrode as the cathode in the cathode chamber and a metal electrode or carbon electrode as the anode in the anode chamber. Connect the electrolyte circulation unit to the electrolyte inlet and electrolyte outlet of the reactor. Connect the cathode and anode to the charge and discharge control module through external wires to complete the battery system construction.

[0010] S2: Circulating electrolyte supply: Electrolyte containing metal ions is continuously circulated into the anode chamber through the electrolyte circulation unit;

[0011] S3: Hydrogen storage by charging: Hydrogen-containing gas is continuously introduced into the cathode chamber, and the charging voltage or charging current is applied to the battery system through the charging and discharging control module to carry out electrochemical charging; During the charging process, the cathode undergoes a hydrogen oxidation reaction, and the anode undergoes a metal ion reduction and deposition reaction, storing hydrogen energy in the anode in solid form as a metallic element.

[0012] S4: Hydrogen generation during discharge: The charge and discharge control module applies a discharge load to the battery system to perform electrochemical discharge; during the discharge process, the anode undergoes an oxidation and dissolution reaction of the metal element, and the cathode undergoes a hydrogen evolution reaction, generating hydrogen gas in situ at the cathode, thus realizing the on-demand release of hydrogen energy.

[0013] As a further technical solution of the present invention: in step S1, the thickness of the cathode and the anode are both controlled to be 10μm-2000μm, and the geometric area of ​​the cathode and the anode is both controlled to be 0.1cm²-1000cm².

[0014] The anode is a thin sheet electrode or a porous electrode made of any one or more of magnesium, aluminum, zinc, iron, tin, lead, copper, silver, gold, and carbon.

[0015] The cathode is made of one or more composites of carbon fiber, nickel foam, functional ion exchange membrane, and stainless steel mesh; the cathode has a pre-fabricated gas diffusion channel with a diameter controlled between 0.01 μm and 5000 μm, and the porosity of the cathode is controlled between 0.1% and 80%.

[0016] As a further technical solution of the present invention: In step S1, the surface of the cathode is preloaded with a catalyst, the catalyst being selected from one or more combinations of platinum, platinum black, nickel, iron, copper, silver, gold, cobalt, manganese, palladium, rhodium, rubidium, ruthenium and their alloys; or the catalyst is one or more combinations of transition metal sulfides, selenides, phosphides, carbides and nitrides.

[0017] As a further technical solution of the present invention: the loading of the catalyst on the cathode surface is controlled to be 0.01 mg / cm²-10 mg / cm².

[0018] As a further technical solution of the present invention: In step S2, the solute of the electrolyte is one or more of the following: sulfate, sulfite, nitrate, acetate, phosphate, chloride, oxide, or potassium hydroxide and sodium hydroxide, containing magnesium, aluminum, zinc, iron, tin, lead, and copper ions; the solvent of the electrolyte is water or an organic solvent; in step S2, the circulation flow rate of the electrolyte is controlled to be 0.01 mL / min-1000 mL / min.

[0019] As a further technical solution of the present invention: in step S3, the hydrogen-containing gas is any one of hydrogen, hydrogen-argon mixture, or hydrogen-nitrogen mixture.

[0020] As a further technical solution of the present invention: in steps S3 and S4, the current density of the battery system charging and discharging is controlled to be 0.1mA / cm²-10000mA / cm².

[0021] As a further technical solution of the present invention: during the reaction process of steps S3 and S4, the working temperature of the reactor is controlled between -60℃ and 100℃ by the temperature control unit, and the operating pressure of the battery system is controlled between 0.1MPa and 10MPa by the pressure regulation unit.

[0022] As a further technical solution of the present invention: In step S1, the shell of the reactor, the pipeline and chamber of the electrolyte circulation unit are all made of one or more of acrylic, polypropylene, fluoroplastic, stainless steel and titanium.

[0023] As a further technical solution of the present invention: In step S1, the battery system constructed includes at least one single cell, and multiple single cells are combined and arranged in the reactor in series or parallel.

[0024] As a further technical solution of the present invention: the round-trip electrical energy efficiency of the battery system is controlled at 70%-100%, and the areal capacity is controlled at 0.1mAh / cm²-10Ah / cm².

[0025] One or more technical solutions provided in the embodiments of this application have at least the following technical effects or advantages:

[0026] Significantly improved hydrogen storage safety: This invention stores hydrogen energy in the form of a solid metal element under normal pressure through an electrochemical coupling reaction, completely avoiding the safety hazards of high-pressure gaseous hydrogen storage, and eliminating the need for a complex thermal insulation system for low-temperature liquid hydrogen storage. The storage conditions are mild, and the transportation and maintenance costs are low, making it suitable for large-scale hydrogen energy storage scenarios.

[0027] Significantly improved energy efficiency: This invention eliminates the slow anodic oxygen evolution reaction in traditional water electrolysis technology, and uses the hydrogen hydroxide reaction coupled with the two-electron reaction of metal deposition / dissolution. The charge and discharge potential difference is extremely small, which greatly reduces the reaction overpotential and system energy consumption. The round-trip electrical energy efficiency can reach up to 100%, which is far higher than the energy conversion efficiency of traditional water electrolysis hydrogen production-fuel cell power generation.

[0028] Good reversibility of cycles and no by-product generation: During the entire charge-discharge cycle of this invention, only the hydroxide / hydrogen evolution reaction at the cathode and the metal deposition / dissolution reaction at the anode occur. The electrolyte medium can be used in a closed loop without any pollution by-product generation. The electrode reaction has excellent reversibility, the number of cycles can reach more than 100 times, the capacity retention rate is higher than 90%, and it has the ability to operate stably for a long time.

[0029] Highly adaptable and widely applicable: The method of this invention can operate stably in a wide temperature range of -60℃ to 100℃ and a wide pressure range of 0.1MPa to 10MPa. It can be directly integrated with intermittent renewable energy systems such as wind power and photovoltaics to achieve efficient conversion and storage of renewable energy electricity into hydrogen energy. At the same time, it can be scaled up by combining batteries in series and parallel, making it suitable for distributed hydrogen energy sites as well as large-scale hydrogen energy storage power stations.

[0030] The process is simple and the cost is controllable: The method of this invention is modular and can achieve stable operation without relying on precious metal catalysts. The core supporting equipment and materials are all conventional industrial products. The equipment cost and operation and maintenance cost are far lower than those of traditional water electrolysis systems and high-pressure hydrogen storage supporting processes, which has extremely strong commercial promotion value. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of the single-cell battery structure upon which the method of this invention is based;

[0032] Figure 2 The images show X-ray diffraction (XRD) phase analysis of the anode before and after charging in Example 1 of this invention.

[0033] Figure 3 This is a charge-discharge voltage curve of the battery system in Embodiment 1 of the present invention at a current density of 50 mA / cm².

[0034] Figure 4 This is a comparison image of the scanning electron microscope (SEM) morphology of the anode before and after charging in Embodiment 1 of the present invention;

[0035] Figure 5 This is a graph showing the cycle stability test results of the battery system in Embodiment 1 of the present invention.

[0036] Figure 6 This is a comparison chart of the average charging and discharging voltages of the battery under different current densities in Embodiment 1 of the present invention;

[0037] Figure 7 This is a battery charge / discharge voltage curve at a current density of 10 mA / cm² in Embodiment 1 of the present invention.

[0038] Explanation of reference numerals in the attached diagram: 1-Metal electrode (anode), 2-Electrolyte chamber, 3-Gas diffusion electrode (cathode). Detailed Implementation

[0039] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0040] like Figures 1-7 As shown, this invention proposes a technical solution from two aspects: hardware device design and method implementation. The system serves as the hardware carrier of the method, and the method achieves full-process management of hardware breakpoints through the collaborative work of various modules of the system.

[0041] A method for a hydrogen-assisted rechargeable battery for hydrogen storage and production includes the following steps:

[0042] Step S1: Provide a reactor, which is equipped with a cathode chamber and an anode chamber. Cut gas diffusion electrodes (or membrane electrodes) are used as cathodes and metal electrodes (or carbon electrodes) are used as anodes. The reactor is assembled with electrolyte to form a battery.

[0043] Step S2: Continuously introduce an electrolyte containing metal ions into the battery using an external circulation pump, while connecting the positive and negative terminals of the battery to an external circuit via wires.

[0044] Step S3: Introduce hydrogen-containing gas into the cathode chamber and apply voltage or current to the external circuit to electrochemically charge the battery, depositing hydrogen as a metallic element on the anode; apply a load to the external circuit to electrochemically discharge, causing the deposited metal to oxidize and dissolve while simultaneously generating hydrogen gas at the cathode;

[0045] Step S4): During scale-up, multiple single cells are connected in series and parallel, placed in a reactor, and electrochemical tests are performed.

[0046] Throughout the electrochemical testing process, the reactor's operating temperature was controlled by an external temperature control system, and the system's operating pressure was controlled by a pressure regulating device.

[0047] In step S1, the thickness of the metal electrode (or carbon electrode) and the gas diffusion electrode (or membrane electrode) is 10-2000 micrometers; the metal electrode (or carbon electrode) is a thin sheet or porous electrode formed by any one or more combinations of magnesium, aluminum, zinc, iron, tin, lead, copper, silver, gold, and carbon; the gas diffusion electrode (or membrane electrode) is composed of one or more composites of carbon fiber, nickel foam, functional ion exchange membrane, and stainless steel mesh; the gas diffusion of the gas diffusion electrode, membrane electrode, porous metal foil, or porous carbon electrode is... The electrode diameter is 0.01 to 5000 micrometers, the porosity is 0.1% to 80%, and the geometric area of ​​the electrode is 0.1 to 1000 square centimeters. The supported catalyst is selected from one or more combinations of platinum, platinum black, nickel, iron, copper, silver, gold, cobalt, manganese, palladium, rhodium, rubidium, ruthenium, and their alloys. The catalyst can also be a non-noble metal-based catalyst, such as one or more combinations of transition metal sulfides, selenides, phosphides, carbides, or nitrides. The catalyst loading is 0.01 to 10 milligrams per square centimeter.

[0048] In step S2, the electrolyte solute is one or more of the following: sulfates, sulfites, nitrates, acetates, phosphates, chlorides, oxides, potassium hydroxide, and sodium hydroxide, containing magnesium, aluminum, zinc, iron, tin, lead, and copper ions. The electrolyte solvent is water or other organic solvents. The electrolyte flow rate is 0.01-1000 ml per minute.

[0049] In step S3, the atmosphere provided during the charging and discharging of the full battery is any one of hydrogen, hydrogen-argon mixture, or hydrogen-nitrogen mixture that can provide hydrogen molecules; the current density during the charging and discharging of the full battery is 0.1-10000 mA per square centimeter; by optimizing the electrode structure, electrolyte composition, and operating conditions, the round-trip energy efficiency (based on electrical energy) of the battery system can reach 70-100%, achieving a capacity of 0.1 mA per square centimeter to 10 Ah per square centimeter.

[0050] In step S4, the reactor includes a shell, and a cathode chamber and an anode chamber disposed within the shell; a gas diffusion electrode (or membrane electrode) is disposed in the cathode chamber as a cathode, and a metal electrode (or carbon electrode) is disposed in the anode chamber as an anode; the reactor shell is provided with a hydrogen inlet and an outlet communicating with the cathode chamber, and an electrolyte inlet and an outlet communicating with the anode chamber; the reactor shell, fluid pipelines and chambers are made of one or more of acrylic, polypropylene, fluoroplastics, stainless steel or titanium, and have good acid and alkali resistance and airtightness; the reactor operating temperature is controlled between -60 degrees Celsius and 100 degrees Celsius; the system operating pressure is 0.1 MPa to 10 MPa.

[0051] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within the present invention.

[0052] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style of the specification is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment have been appropriately combined to form other embodiments that are easily understood by those skilled in the art.

Claims

1. A method for hydrogen-assisted rechargeable batteries for hydrogen storage and production, characterized in that, Includes the following steps: S1: Battery Assembly: Set up a cathode chamber and an anode chamber that are isolated from each other in the reactor. Install a gas diffusion electrode or membrane electrode as the cathode in the cathode chamber and a metal electrode or carbon electrode as the anode in the anode chamber. Connect the electrolyte circulation unit to the electrolyte inlet and electrolyte outlet of the reactor. Connect the cathode and anode to the charge and discharge control module through external wires to complete the battery system construction. S2: Circulating electrolyte supply: Electrolyte containing metal ions is continuously circulated into the anode chamber through the electrolyte circulation unit; S3: Hydrogen storage by charging: Hydrogen-containing gas is continuously introduced into the cathode chamber, and the charging voltage or charging current is applied to the battery system through the charging and discharging control module to carry out electrochemical charging; During the charging process, the cathode undergoes a hydrogen oxidation reaction, and the anode undergoes a metal ion reduction and deposition reaction, storing hydrogen energy in the anode in solid form as a metallic element. S4: Hydrogen generation during discharge: The charge and discharge control module applies a discharge load to the battery system to perform electrochemical discharge; during the discharge process, the anode undergoes an oxidation and dissolution reaction of the metal element, and the cathode undergoes a hydrogen evolution reaction, generating hydrogen gas in situ at the cathode, thus realizing the on-demand release of hydrogen energy.

2. The method for hydrogen-assisted rechargeable battery for hydrogen storage and production according to claim 1, characterized in that, In step S1, the thickness of both the cathode and the anode is controlled to be 10μm-2000μm, and the geometric area of ​​both the cathode and the anode is controlled to be 0.1cm²-1000cm². The anode is a thin sheet electrode or a porous electrode made of any one or more of magnesium, aluminum, zinc, iron, tin, lead, copper, silver, gold, and carbon. The cathode is made of one or more composites of carbon fiber, nickel foam, functional ion exchange membrane, and stainless steel mesh; the cathode has a pre-fabricated gas diffusion channel with a diameter controlled between 0.01 μm and 5000 μm, and the porosity of the cathode is controlled between 0.1% and 80%. The surface of the cathode is preloaded with a catalyst, which is selected from one or more combinations of platinum, platinum black, nickel, iron, copper, silver, gold, cobalt, manganese, palladium, rhodium, rubidium, ruthenium and their alloys; or the catalyst is one or more combinations of transition metal sulfides, selenides, phosphides, carbides and nitrides.

3. The method for hydrogen-assisted rechargeable battery for hydrogen storage and production according to claim 2, characterized in that, The catalyst loading on the cathode surface is controlled to be 0.01 mg / cm²-10 mg / cm².

4. The method for hydrogen-assisted rechargeable battery for hydrogen storage and production according to claim 1, characterized in that, In step S2, the solute of the electrolyte is one or more of the following: sulfates, sulfites, nitrates, acetates, phosphates, chlorides, oxides, or potassium hydroxide and sodium hydroxide, containing magnesium, aluminum, zinc, iron, tin, lead, and copper ions; the solvent of the electrolyte is water or an organic solvent; and the circulation flow rate of the electrolyte in step S2 is controlled to be 0.01 mL / min-1000 mL / min.

5. The method for hydrogen-assisted rechargeable battery for hydrogen storage and production according to claim 1, characterized in that, In step S3, the hydrogen-containing gas is any one of hydrogen, a hydrogen-argon mixture, or a hydrogen-nitrogen mixture.

6. The method for hydrogen-assisted rechargeable battery for hydrogen storage and production according to claim 1, characterized in that, In steps S3 and S4, the current density of the battery system during charging and discharging is controlled to be 0.1 mA / cm²-10000 mA / cm².

7. The method for hydrogen-assisted rechargeable battery for hydrogen storage and production according to claim 1, characterized in that, During the reaction processes in steps S3 and S4, the operating temperature of the reactor is controlled between -60℃ and 100℃ by the temperature control unit, and the operating pressure of the battery system is controlled between 0.1MPa and 10MPa by the pressure regulation unit.

8. The method for hydrogen-assisted rechargeable battery for hydrogen storage and production according to claim 1, characterized in that, In step S1, the reactor shell, the pipelines and chambers of the electrolyte circulation unit are all made of one or more of acrylic, polypropylene, fluoroplastics, stainless steel and titanium.

9. The method for hydrogen-assisted rechargeable battery for hydrogen storage and production according to claim 1, characterized in that, In step S1, the constructed battery system includes at least one individual cell, and multiple individual cells are combined and arranged in the reactor in series or parallel.

10. The method for hydrogen-assisted rechargeable battery for hydrogen storage and production according to claim 1, characterized in that, The round-trip energy efficiency of the battery system is controlled at 70%-100%, and the areal capacity is controlled at 0.1mAh / cm²-10Ah / cm².

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