Negative electrode applied to lithium-hydrogen battery and preparation method thereof, lithium-hydrogen battery

Abstract

The application provides a negative electrode applied to a lithium-hydrogen battery and a preparation method of the negative electrode, and the lithium-hydrogen battery, and belongs to the technical field of electrochemical energy storage. The application provides a preparation method of a negative electrode applied to a lithium-hydrogen battery, which comprises the following steps: preparing a silicon nanomaterial slurry; uniformly coating the silicon nanomaterial slurry on one surface of a metal foil current collector, drying and rolling to form a silicon nanomaterial coating on the metal foil current collector, thereby forming a negative electrode precursor; and assembling the negative electrode precursor and an electrolyte containing lithium ions into a lithium-hydrogen battery to perform first charging, so that lithium ions are embedded into the negative electrode precursor to form a lithiumophilic interface, thereby forming the negative electrode. The application further provides a negative electrode and a lithium-hydrogen battery applying the negative electrode.

Description

Technical Field

[0001] At least one embodiment of the present invention relates to a lithium-hydrogen battery, and more particularly to a negative electrode for use in a lithium-hydrogen battery and a method for preparing the same, and the lithium-hydrogen battery itself. Background Technology

[0002] With the continuous growth of global energy demand, the development and storage of clean energy technologies have become a key research focus. Currently, energy storage technologies encompass various methods, primarily including mechanical energy storage, electrochemical energy storage, electromagnetic energy storage, and chemical energy storage. In the field of electrochemical energy storage, hydrogen batteries using catalytic hydrogen electrodes as the negative electrode offer advantages such as low cost and long cycle life.

[0003] Taking nickel-metal hydride (NiMH) batteries as an example, they store and release energy through the hydrogen evolution reaction (HER) / hydrogen oxidation reaction (HOR) of hydrogen during charge and discharge. However, using hydrogen as the negative electrode limits the selection of positive electrode materials and results in a lower battery operating voltage, leading to lower energy density per cell. Therefore, lithium-hydrogen (Li-MH) batteries, which fully utilize the advantages of hydrogen electrodes by further expanding the operating voltage of hydrogen batteries, represent a promising new battery system. Conventional Li-MH batteries require the use of highly reactive lithium metal as the negative electrode during assembly, resulting in high production costs, complex processes, and certain safety risks. Summary of the Invention

[0004] In view of this, in order to at least partially solve the aforementioned technical problems, the present invention provides a negative electrode for use in lithium-hydrogen batteries and a method for preparing the same, as well as a lithium-hydrogen battery, to reduce production costs and process difficulty, and to improve energy density.

[0005] According to one embodiment of the present invention, a method for preparing a negative electrode for a lithium-hydrogen battery is provided, comprising:

[0006] Prepare a silicon nanomaterial slurry; uniformly coat the silicon nanomaterial slurry onto one surface of a metal foil current collector, dry and roll it to form a silicon nanomaterial coating on the metal foil current collector, forming a negative electrode precursor; and assemble the negative electrode precursor and a lithium-ion-containing electrolyte into a lithium-hydrogen battery for the first charge, so that lithium ions are embedded in the negative electrode precursor to form a lithium-affinity interface, forming a negative electrode.

[0007] According to another aspect of the present invention, a negative electrode for use in a lithium-hydrogen battery, obtained by the above-described preparation method, is provided, comprising:

[0008] Metal foil current collector;

[0009] as well as

[0010] Lithophilic interfaces, including lithium-silicon alloys, are located on metal foil current collectors.

[0011] According to one aspect of the present invention, a lithium-hydrogen battery is provided, comprising: an electrolyte; and a positive electrode adapted for proton (H+) exchange at the interface between the positive electrode and the electrolyte. + The redox reaction between lithium metal and gaseous H2; the negative electrode prepared above is suitable for redox reaction between lithium metal and lithium ions at the interface between the negative electrode and the electrolyte.

[0012] According to the above-described embodiment of the present invention, a method for preparing a negative electrode for lithium-hydrogen batteries is used to form a silicon nanomaterial coating on a metal foil current collector. During the first charging process, a lithiophilic interface is formed in situ on the silicon nanomaterial coating. This lithiophilic interface facilitates efficient, dense, and stable subsequent lithium deposition, resulting in a negative electrode. Applying this negative electrode to a lithium-hydrogen battery can yield a high-energy-density lithium-hydrogen battery. Furthermore, the negative electrode provided by this invention is based on existing material systems, has low preparation costs, and offers higher safety compared to simple lithium negative electrode materials. Attached Figure Description

[0013] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings of the embodiments will be briefly described below. Obviously, the drawings described below only relate to some embodiments of the present invention and are not intended to limit the present invention.

[0014] Figure 1 This is a schematic flowchart of a method for preparing a negative electrode for a lithium-hydrogen battery according to an embodiment of the present invention.

[0015] Figure 2 This is a schematic diagram of the negative electrode of a lithium-hydrogen battery provided in an embodiment of the present invention;

[0016] Figure 3 This is a schematic diagram of a lithium-hydrogen battery provided in an embodiment of the present invention;

[0017] Figure 4 A scanning electron microscope image of the silicon nanoparticles used in the preparation of the negative electrode provided in Example 1 of the present invention;

[0018] Figure 5 This is a schematic diagram of a metal foil current collector loaded with a silicon nanomaterial coating provided in Embodiment 1 of the present invention;

[0019] Figure 6 The charge-discharge curves of the lithium-hydrogen battery provided in Example 1 of the present invention under a specified capacity test at a current density of 1000 mA / g and a capacity of 1000 mAh / g, where mA / g represents the current passing through a unit mass of positive electrode catalyst (Pt / C) and mAh / g represents the electrical energy catalyzed by a unit mass of positive electrode catalyst (Pt / C) for hydrogen / proton conversion.

[0020] Figure 7 This is a comparison chart of the cycle performance of the lithium-hydrogen battery provided in Example 1 of the present invention and the cycle performance of the lithium-hydrogen battery in Comparative Example 1.

[0021] Figure 8 The charge-discharge curves of the lithium-hydrogen battery provided in Example 2 of this invention under a specified capacity test at a current density of 1000 mA / g and a capacity of 1000 mAh / g; and

[0022] Figure 9 The charge-discharge curves of the lithium-hydrogen battery provided in Example 3 of the present invention under a specified capacity test at a current density of 1000 mA / g and a capacity of 1000 mAh / g.

[0023] Explanation of reference numerals in the attached figures:

[0024] 1- Negative electrode;

[0025] 11-Metal foil current collector;

[0026] 12-Silicon nanomaterial coating;

[0027] 13-Lithophile interface;

[0028] 2-Organic electrolytes;

[0029] 3-Solid electrolyte membrane;

[0030] 4- Positive electrode electrolyte;

[0031] 5-Positive electrode. Detailed Implementation

[0032] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to specific embodiments and the accompanying drawings. However, this invention can be implemented in different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided to make the invention thorough and complete, and to fully convey the scope of the invention to those skilled in the art. In the accompanying drawings, for clarity, the dimensions and relative dimensions of layers and regions may be exaggerated, and the same reference numerals denote the same elements throughout.

[0033] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the invention. The terms “comprising,” “including,” etc., as used herein indicate the presence of the stated features, steps, operations, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, or components.

[0034] Figure 1 This is a schematic flowchart illustrating a method for preparing a negative electrode for a lithium-hydrogen battery, as provided in an embodiment of the present invention.

[0035] According to an exemplary embodiment of the present invention, the present invention provides a method for preparing a negative electrode for a lithium-hydrogen battery, referring to... Figure 1 As shown, it includes: operations S01 to S03.

[0036] Operate S01 to prepare silicon nanomaterial slurry.

[0037] In some embodiments, the preparation of silicon nanomaterial slurry includes: mixing silicon nanoparticles, binder and conductive agent to obtain a mixed solid material, adding solvent dropwise into the mixed solid material, stirring at room temperature for 2h~8h and then degassing under vacuum to obtain silicon nanomaterial slurry.

[0038] In some embodiments, the general formula of silicon nanoparticles is SiO. x Where 0 < x < 2; the particle size D50 of silicon nanoparticles is any value between 50 nm and 500 nm, such as 50 nm, 100 nm, 200 nm, 300 nm, and 500 nm, but not limited to these values. Nanoscale silicon materials have the smallest expansion effect and are the most stable silicon materials. A particle size D50 of 50 nm to 500 nm for silicon nanoparticles ensures high stability of the in-situ formed Li-SiOx alloy and avoids structural damage due to the expansion effect of Si.

[0039] In some embodiments, the adhesive comprises one or more of carboxymethyl cellulose (CMC), polyvinylidene fluoride (PVDF), polyacrylonitrile (PAN), sodium alginate (Alg), polyacrylic acid (PAA), styrene-butadiene rubber (SBR), polyamide (PAI), polyvinyl alcohol (PEI), and polyimide (PI).

[0040] In some embodiments, the conductive agent includes one or more of acetylene black, Ketjen black, carbon nanotubes, and graphene.

[0041] In some embodiments, the solvent used is one or more of deionized water, ethylene glycol dimethyl ether (DMF), N-methylpyrrolidone (NMP), and N,N-dimethylformamide (DME).

[0042] In some embodiments, the solid-liquid ratio of the mixed solid material to the solvent is any value from 0.05 kg / L to 0.2 kg / L, such as 0.05 kg / L, 0.1 kg / L, 0.15 kg / L, 0.18 kg / L, and 0.2 kg / L, but is not limited to these values. The viscosity of the coating slurry formed when the solid-liquid ratio of the mixed solid material to the solvent is 0.05 kg / L to 0.2 kg / L ensures uniform coating.

[0043] In some embodiments, the mass ratio of silicon nanoparticles to binder is (1~8):1, for example, 1:1, 2:1, 4:1, 6:1, 8:1, but not limited to these values. Different Si material particle sizes require different binder contents because smaller silicon materials have a larger specific surface area, requiring more binder to ensure coating effect. Experiments have shown that for silicon nanoparticles with a particle size D50 of 50nm~500nm, a mass ratio of silicon nanoparticles to binder of (1~8):1 can achieve good coating effect. In some embodiments, the mass ratio of conductive agent to binder is 0~50%, and not 0.

[0044] In some embodiments, silicon nanoparticles include one or more of silicon, silicon dioxide, and silicon oxides.

[0045] In step S02, the silicon nanomaterial slurry is uniformly coated onto one surface of the metal foil current collector. After drying and rolling, a silicon nanomaterial coating is formed on the metal foil current collector, thus forming the negative electrode precursor.

[0046] In some embodiments, the metal foil current collector is a metal or its alloy, and the metal foil current collector includes one or more of Cu, Ag, Au, Ti, Al, Ni, In, Sr and Ba.

[0047] It should be noted that there is no limit to the thickness of the metal foil current collector; it can be set according to actual needs.

[0048] In operation S03, the negative electrode precursor and the lithium-ion-containing electrolyte are assembled into a lithium-hydrogen battery for the first charge, so that lithium ions are inserted into the negative electrode precursor to form a lithium-friendly interface and form a negative electrode.

[0049] According to an embodiment of the present invention, during the first charging process of the assembled lithium-hydrogen battery, lithium ions in the electrolyte of the lithium-hydrogen battery are embedded in the silicon nanomaterial coating to form a lithium-silicon alloy (lithophile interface), and the lithiophile interface will exist permanently after its formation.

[0050] Figure 2 This is a schematic diagram of the negative electrode of a lithium-hydrogen battery provided in an embodiment of the present invention.

[0051] According to an exemplary embodiment of the present invention, the present invention provides a negative electrode for use in a lithium-hydrogen battery, with reference to... Figure 2 As shown, it includes:

[0052] Metal foil current collector 11;

[0053] The lithium-silicon interface 13 includes a lithium-silicon alloy. The lithium-silicon interface is formed during the first charge of the lithium-hydrogen battery. The lithium-silicon interface 13 is located on the metal foil current collector 11.

[0054] In some embodiments, the thickness of the silicon nanomaterial coating formed on the metal foil current collector 11 is any value from 1μm to 5μm, such as 1μm, 2μm, 3μm, 4μm, 5μm, but not limited to the values ​​mentioned.

[0055] In some embodiments, the sum of the thicknesses of the in-situ formed lithiophilic interface 13 of the 1μm~5μm silicon nanomaterial coating is 5μm~10μm, for example, 5μm, 6μm, 7μm, 8μm, 10μm, but not limited to these values. If the thickness of the silicon nanomaterial coating is too small, the Li-SiOx lithiophilic layer that can be formed is too thin, and the effect of stabilizing the negative electrode (keeping the negative electrode stable during cycle) is not obvious. If the thickness is too large, the stress is too high, and peeling and detachment are likely to occur during charge and discharge cycles.

[0056] Figure 3 This is a schematic diagram of a lithium-hydrogen battery provided in an embodiment of the present invention.

[0057] According to an exemplary embodiment of the present invention, the present invention provides a lithium-hydrogen battery, referring to... Figure 3 As shown, it includes, in sequence, a negative electrode 1, an organic electrolyte 2, a solid electrolyte membrane 3, a positive electrolyte 4, and a positive electrode 5.

[0058] According to an embodiment of the present invention, the positive electrode of a lithium-hydrogen battery generates gaseous H2 and protons (H2O). + The redox reaction occurs between lithium metal and lithium ions at the positive electrode, while the redox reaction between lithium metal and lithium ions occurs at the negative electrode. Specifically, during charging, hydrogen gas is oxidized into protons (H+) at the positive electrode. + Lithium ions in the electrolyte (Li) + The protons at the positive electrode are reduced to lithium metal and deposited onto the negative electrode. During discharge, protons at the positive electrode are reduced to H2, while lithium metal at the negative electrode is oxidized to lithium ions. This process is reversible, allowing the battery to undergo multiple charge-discharge cycles without failure.

[0059] According to embodiments of the present invention, the active material (lithium metal) of the negative electrode provided by the present invention is formed during charging and disappears during discharging, thus eliminating inactive mass in the negative electrode. In other words, the lithium active material provided by the present invention can achieve 100% conversion into lithium metal and deposition onto the negative electrode precursor to form the negative electrode. Compared to directly using lithium metal as the negative electrode, this achieves extremely high active material utilization and extremely high energy density in lithium-hydrogen batteries.

[0060] According to embodiments of the present invention, a negative electrode for lithium-hydrogen batteries and its preparation method are provided. Instead of directly using highly reactive lithium as the negative electrode, a copper foil current collector coated with silicon nanomaterials is used as the negative electrode precursor. This design simplifies, safes, and reduces the cost of manufacturing lithium-hydrogen batteries. During the first charge cycle, lithium in the lithium-hydrogen battery is deposited on the silicon nanomaterial coating, forming a lithium-silicon alloy lithiophilic interface. Subsequent lithium ions are deposited on this lithiophilic interface. This design significantly improves the energy density of lithium-hydrogen batteries by eliminating the need for a pre-existing lithium negative electrode.

[0061] According to embodiments of the present invention, the lithium-hydrogen battery with negative electrode assembly of the present invention can achieve ultra-high reversible areal capacity, specifically, the coulombic efficiency (discharge capacity / charge capacity) of the lithium-hydrogen battery with negative electrode assembly of the present invention can be maintained at above 98.5%.

[0062] It should be noted that in the related technologies, the silicon anode (using silicon as the anode) will expand three times in volume during charging and discharging, which will accelerate the damage of the anode. Compared with the silicon anode, the anode provided in the embodiments of the present invention remains stable after forming a lithium-friendly interface, and its volume is not easily expanded, which is beneficial to maintaining the performance stability of the anode.

[0063] The following schematic illustration illustrates the design of a negative electrode for use in lithium-hydrogen batteries, its preparation method, and the lithium-hydrogen battery itself. It should be noted that this illustration is merely a specific embodiment of the present invention and does not limit the scope of protection of the present invention.

[0064] Example 1

[0065] Prepare copper foil current collectors with silicon nanomaterial coatings.

[0066] Specifically, under normal temperature and pressure, Si nanoparticles and CMC powder were mixed at a ratio of 300 mg and 100 mg, respectively, and 50 mg of conductive carbon black was added. The mixture was then stirred for 2 hours to ensure uniform mixing of the solid powders. Next, 5 mL of deionized water was slowly added to the mixed powder. After the addition was complete, the slurry was stirred for another 6 hours. The homogenized slurry was then placed in a vacuum chamber for 10 seconds to remove bubbles. A suitable amount of slurry was then drop-coated onto a cleaned copper foil surface using a doctor blade, with the blade thickness set to 2 μm. The coated copper foil current collector was then placed in an oxygen-free oven and dried at 75°C for 6 hours to obtain the negative electrode precursor.

[0067] Figure 4 This is a scanning electron microscope image of the silicon nanoparticles used in the preparation of the negative electrode provided in Example 1 of the present invention.

[0068] refer to Figure 4 As shown, the particle size of silicon nanoparticles is approximately 1000 nm.

[0069] Figure 5 This is a schematic diagram of a metal foil current collector loaded with a silicon nanomaterial coating, provided in Embodiment 1 of the present invention.

[0070] refer to Figure 5 As shown, a silicon nanomaterial coating 12 is formed on the copper foil current collector 11.

[0071] Prepare a lithium-hydrogen battery. Specifically, dissolve lithium salt in a mixed organic solvent (DME to DOL volume ratio of 1:1) to form an organic electrolyte 2. Use lithium aluminum titanium phosphate (LATP) as a solid electrolyte membrane 3. Use sulfuric acid as the positive electrode electrolyte 4. Select a 5% mass fraction Pt / C catalyst as the positive electrode catalyst, use PVDF as a binder and NMP as a solvent, homogenize and coat it onto a gas diffusion layer (GDL) to prepare the positive electrode 5.

[0072] The negative electrode precursor, organic electrolyte 2, solid electrolyte membrane 3, positive electrode electrolyte 4, and positive electrode 5 prepared in Example 1 were assembled into a lithium-hydrogen battery.

[0073] refer to Figure 1 As shown, after the first charge of the assembled lithium-hydrogen battery, a lithium-friendly interface 13 is formed in situ on the silicon nanomaterial coating 12 of the negative electrode precursor.

[0074] Figure 6 The charge-discharge curves of the lithium-hydrogen battery provided in Example 1 of this invention under a specified capacity test at a current density of 1000 mA / g and a capacity of 1000 mAh / g.

[0075] refer to Figure 6 As shown, the lithium-hydrogen battery prepared in Example 1 was tested using a charge / discharge current of 1000 mA / g and a specified capacity of 1000 mAh / g. The bending curve during the initial phase of the first charge cycle represents the formation of a lithiophilic interface. After the lithiophilic interface is formed during the first charge cycle, the bending curve disappears during the second charge cycle.

[0076] In Example 1, the total weight of the electrode nano-coating is 0.12 mg. Based on the mass ratio, the Si material content can be calculated to be 0.09 mg. The theoretical capacity of the Si material is 4200 mAh / g. Therefore, the required charging capacity of the lithium-silicon alloy can be calculated as: 0.09 / 1000*4200=0.378 mAh.

[0077] The lithium-hydrogen battery cathode catalyst content is 1 mg, therefore the calculated capacity is 378 mAh / g. Figure 6 The slope of the first charging cycle flattens out at the same point.

[0078] Comparative Example 1

[0079] The process for preparing the lithium-hydrogen battery is the same as in Example 1, except that a copper current collector is used for the negative electrode.

[0080] Figure 7 This is a comparison chart of the cycle performance of the lithium-hydrogen battery provided in Example 1 of the present invention and the cycle performance of the lithium-hydrogen battery in Comparative Example 1.

[0081] refer to Figure 7 As shown, the electrochemical performance of the lithium-hydrogen battery of Example 1 of the present invention is significantly better than that of the lithium-hydrogen battery of Comparative Example 1. Furthermore, the battery of Example 1 also exhibits good cycle stability. Compared to the lithium-hydrogen battery of Comparative Example 1, the lithium-hydrogen battery of Example 1 has a higher lithium metal utilization rate during cycling, and its coulombic efficiency during cycling is higher (the coulombic efficiency of the lithium-hydrogen battery of Example 1 reaches 98.5%, while the coulombic efficiency of the lithium-hydrogen battery of Comparative Example 1 is less than 98%). Simultaneously, Example 1 exhibits more stable cycling than Comparative Example 1, as demonstrated by… Figure 7 Embodiment 1 of the present invention has a smoother coulombic efficiency curve and steadily increases during the cycle.

[0082] This is because, in Comparative Example 1, directly depositing a lithium metal layer on a copper current collector results in a loose lithium metal structure with numerous defects, making it prone to lithium dendrite formation. Consequently, the lithium-hydrogen battery formed as the negative electrode is prone to performance degradation during cyclic charging and discharging. In Example 1 of this invention, the negative electrode involves first depositing a silicon nanomaterial coating on a metal foil current collector, and then forming a lithiophilic interface in situ on the silicon nanomaterial coating. This lithiophilic interface induces the formation of a dense, uniform, and thicker metal alloy as the negative electrode, resulting in a negative electrode with greater capacity and stability during cyclic charging and discharging.

[0083] Example 2

[0084] The process for preparing lithium-hydrogen batteries is the same as in Example 1, except that the silicon nanoparticles used to prepare the negative electrode precursor include SiO2.

[0085] A copper foil current collector coated with silicon nanomaterials was prepared. Specifically, under ambient temperature and pressure, SiO2 nanoparticles and PVDF powder were mixed at a ratio of 400 mg and 100 mg, respectively, and 50 mg of conductive carbon black was added. The mixture was then stirred for 2 hours to ensure uniform mixing of the solid powders. Next, 10 mL of NMP was slowly added to the stirred powder mixture. After the addition was complete, the slurry was stirred for another 8 hours. The homogenized slurry was placed in a vacuum chamber for 10 seconds to remove bubbles. Then, an appropriate amount of slurry was drop-coated onto a cleaned copper foil surface using a doctor blade, with the blade thickness set to 4 μm. The coated copper foil current collector was then dried in an oxygen-free oven at 80 °C for 6 hours to obtain the negative electrode precursor.

[0086] Figure 8 The charge-discharge curves of the lithium-hydrogen battery provided in Example 2 of the present invention under a specified capacity test at a current density of 1000 mA / g and a capacity of 1000 mAh / g.

[0087] refer to Figure 8 As shown, in the initial stage of charging, the voltage curve gradually rises with a certain curvature, representing the alloying process of SiOx and Li, which is the formation process of the lithium-loving interface. After the silicon nanomaterial coating is fully lithium-intercalated, the voltage curve begins to flatten, which indicates that lithium metal begins to be deposited stably. In the subsequent discharge process, a voltage cutoff of 2.5V is set to avoid the discharge of lithium-intercalated SiOx.

[0088] Example 3

[0089] The process for preparing the lithium-hydrogen battery is the same as in Example 1, except that the silicon nanoparticles used to prepare the negative electrode precursor include SiO.

[0090] A copper foil current collector coated with silicon nanomaterials was prepared. Specifically, under ambient temperature and pressure, SiO nanoparticles and PAN powder were mixed at a ratio of 400 mg and 50 mg, respectively, and 20 mg of conductive carbon black was added. The mixture was then stirred for 2 hours to ensure uniform mixing of the solid powders. Next, 6 mL of DMF was slowly added to the mixed powder. After the addition was complete, the slurry was stirred for another 6 hours. The homogenized slurry was placed in a vacuum chamber for 10 seconds to remove bubbles. Then, an appropriate amount of slurry was drop-coated onto a cleaned copper foil surface using a doctor blade, with the blade thickness set to 3 μm. The coated copper foil current collector was then dried in an oxygen-free oven at 80°C for 6 hours to obtain the negative electrode precursor.

[0091] Figure 9 The charge-discharge curves of the lithium-hydrogen battery provided in Example 3 of the present invention under a specified capacity test at a current density of 1000 mA / g and a capacity of 1000 mAh / g.

[0092] refer to Figure 9 As shown, in the initial stage of charging, the voltage curve gradually rises with a certain curvature, representing the alloying process of SiOx and Li, which is the formation process of the lithium-loving interface. After the silicon nanomaterial coating is fully lithium-intercalated, the voltage curve begins to flatten, which indicates that lithium metal begins to be deposited stably. In the subsequent discharge process, a voltage cutoff of 2.5V is set to avoid the discharge of lithium-intercalated SiOx.

[0093] Example 4

[0094] The process for preparing the lithium-hydrogen battery is the same as in Example 3, except that the binder used to prepare the negative electrode precursor is CMC, and the mass ratio of SiO nanoparticles to CMC powder is 3:1.

[0095] A copper current collector anode with a silicon nanomaterial coating was prepared. Specifically, under ambient temperature and pressure, SiO nanoparticles and CMC powder were mixed at a ratio of 300 mg and 100 mg, respectively, and 10 mg of conductive carbon black was added. The mixture was then stirred for 2 hours to ensure uniform mixing of the solid powders. Next, 5 mL of deionized water was slowly added to the mixed powder. After the addition was complete, the slurry was stirred for another 6 hours. The homogenized slurry was placed in a vacuum chamber for 10 seconds to remove bubbles. Then, an appropriate amount of slurry was drop-coated onto a cleaned copper foil surface using a doctor blade, with the blade thickness set to 1 μm. The coated copper foil current collector was then dried in an oxygen-free oven at 80°C for 6 hours to obtain the anode precursor.

[0096] Example 5

[0097] The process for preparing the lithium-hydrogen battery is the same as in Example 4, except that the silicon nanoparticles used to prepare the negative electrode precursor include SiO₂. 1.2 .

[0098] A copper current collector with a silicon nanomaterial coating was prepared. Specifically, SiO₂ was coated with silicon nanomaterials in air at room temperature and pressure. 1.2 Nanoparticles and CMC powder were mixed at a ratio of 300 mg and 100 mg, respectively. 10 mg of conductive carbon black was added, and the mixture was stirred for 2 hours to ensure homogeneity. Then, 4.8 mL of deionized water was slowly added to the mixed powder. After the addition was complete, the slurry was stirred for another 6 hours. The homogenized slurry was placed in a vacuum chamber for 10 seconds to remove bubbles. A suitable amount of slurry was then drop-coated onto a cleaned copper foil surface using a doctor blade, with the blade thickness set to 2 μm. The coated copper foil current collector was then placed in an oxygen-free oven and dried at 80 °C for 6 hours to obtain the negative electrode precursor.

[0099] Example 6

[0100] The process for preparing the lithium-hydrogen battery is the same as in Example 5, except that the silicon nanoparticles used to prepare the negative electrode precursor include SiO₂. 0.8 .

[0101] A copper foil current collector with a silicon nanomaterial coating was prepared. Specifically, SiO2 was coated with silicon nanomaterials in air at room temperature and pressure. 0.8 Nanoparticles and CMC powder were mixed at a ratio of 300 mg and 100 mg, respectively. 10 mg of conductive carbon black was added, and the mixture was stirred for 2 hours to ensure homogeneity. Then, 4.8 mL of deionized water was slowly added to the mixed powder. After addition, the slurry was stirred for another 6 hours. The homogenized slurry was placed in a vacuum chamber for 10 seconds to remove bubbles. A suitable amount of slurry was then drop-coated onto a cleaned copper foil surface using a doctor blade, with the blade thickness set to 2 μm. The coated copper foil current collector was then dried in an oxygen-free oven at 80°C for 6 hours to obtain the negative electrode precursor.

[0102] The use of ordinal numbers such as "first," "second," "third," etc., in the specification and claims to modify the corresponding elements does not imply that the element has any ordinal number, nor does it represent the order of one element with another element, or the order of manufacturing methods. The use of these ordinal numbers is only to enable a named element to be clearly distinguished from another element with the same name.

[0103] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for preparing a negative electrode for lithium-hydrogen batteries, characterized in that, include: Preparation of silicon nanomaterial slurry; A silicon nanomaterial slurry is uniformly coated onto one surface of a metal foil current collector, and then dried and rolled to form a silicon nanomaterial coating on the metal foil current collector, thus forming a negative electrode precursor. as well as The negative electrode precursor and the lithium-ion-containing electrolyte are assembled into a lithium-hydrogen battery and charged for the first time to allow lithium ions to embed into the negative electrode precursor to form a lithium-loving interface. Then, lithium ions are deposited on the lithium-loving interface to form the negative electrode.

2. The preparation method according to claim 1, characterized in that, The preparation of the silicon nanomaterial slurry includes: Silicon nanoparticles, binders, and conductive agents are mixed to obtain a mixed solid material. Solvent is added dropwise to the mixed solid material, and the mixture is stirred at room temperature and then defoamed under vacuum to obtain the silicon nanomaterial slurry.

3. The preparation method according to claim 2, characterized in that, The solid-liquid ratio of the mixed solid material to the solvent is 0.05 kg / L to 0.2 kg / L; The mass ratio of silicon nanoparticles to binder is 1~8; The mass ratio of the conductive agent to the adhesive is 0% to 50%, and is not 0.

4. The preparation method according to claim 2, characterized in that, The silicon nanoparticles include one or more of silicon, silicon dioxide, and silicon oxides.

5. The preparation method according to claim 1, characterized in that, The metal foil current collector is a metal or its alloy. The metal foil current collector includes one or more of Cu, Ag, Au, Ti, Al, Ni, In, Sr and Ba.

6. The preparation method according to claim 1, characterized in that, The thickness of the silicon nanomaterial coating (12) is 1 μm to 5 μm.

7. A negative electrode for use in lithium-hydrogen batteries, obtained by the preparation method according to any one of claims 1 to 6, characterized in that, include: Metal foil current collector (11); as well as A lithium-friendly interface (13), comprising a lithium-silicon alloy, is located on the metal foil current collector (11).

8. The negative electrode according to claim 7, characterized in that, The lithium-friendly interface is formed during the first charging of the lithium-hydrogen battery.

9. The negative electrode according to claim 7, characterized in that, The thickness of the lithiophilic interface (13) is 5 μm to 10 μm.

10. A lithium-hydrogen battery, characterized in that, include: Electrolyte; A positive electrode, suitable for carrying out redox reactions between protons and gaseous H2 at the interface between the positive electrode and the electrolyte; The negative electrode according to any one of claims 7 to 9 is suitable for carrying out a redox reaction between lithium metal and lithium ions at the interface between the negative electrode and the electrolyte.

Images