Tritium-volt water-based zinc ion battery

Abstract

A tritium water-based zinc ion battery relates to the field of isotope batteries, and a positive electrode comprises a current collector, a nano-structure semiconductor film, a tritium water radiation source, an active material and a conductive material; the nano-structure semiconductor film is prepared on the current collector; the active material and the conductive material are mixed and then coated on the surface of the nano-structure semiconductor film; the tritiated water radiation source exists in one or more of the following forms: the tritiated water radiation source exists in the nano-structure semiconductor film and / or the active material in the form of crystalline tritiated water; the tritiated water exists in the electrolyte in the form of liquid tritiated water; the electrolyte is an aqueous solution containing zinc ions. Compared with a traditional metal or semiconductor high-temperature and high-pressure tritiation technology, the tritium loading process does not affect the overall physical property of a semiconductor material. And meanwhile, the chemical structure of the tritiated water is stable, the problems of migration, diffusion and escape of tritium do not exist, and the stability of the battery material is ensured.

Description

Technical Field

[0001] The invention relates to the field of isotope batteries, and in particular to a tritiated water-based zinc ion battery. Background Art

[0002] Radioisotope irradiation cells can directly convert the energy of high-energy radiation particles (such as β or α particles) released by radioisotopes during decay into electrical energy through the radiovoltaic effect. They have the advantages of high specific energy density, maintenance-free, and insensitive to the environment and temperature. They have broad application potential and development prospects in aerospace, life and health, ocean monitoring, polar regions, and border areas. However, the trickle power generation of radioisotope irradiation cells cannot meet the immediate needs of high-power equipment. Although the commercial energy storage batteries (such as metal ion batteries and supercapacitors) currently widely used have high specific power density, they require regular charging and maintenance. What is more serious is that it is very difficult to perform charging and maintenance in harsh environments such as deep sea, space, deserts, and polar regions, which increases the difficulty and operating cost of equipment operation. A feasible solution is to integrate the irradiation unit and the energy storage unit in one device to realize the simultaneous collection, conversion, and storage of radiation energy. The trickle power generation of the irradiation unit is used to trickle charge the energy storage unit to realize the conversion of radiation energy → electrical energy → chemical energy. The battery charging maintenance is realized through self-generation and self-charging to meet the intermittent working requirements of high-power electronic equipment.

[0003] In order to achieve high energy storage capacity, the lithium-ion battery structure based on electrochemical redox reaction is an ideal energy storage structure solution. However, lithium-ion batteries usually use some polymer electrolytes, which may be damaged and fail due to radiation decomposition effects during long-term use.

[0004] From the perspective of the use of isotope radiation sources, factors that need to be considered include the half-life of the isotope source, the energy of the radiation particles, the availability of isotopes, and the manufacturing cost. Generally, the radiation damage threshold of semiconductors is 250 KeV, so some radiation sources that radiate high-energy α and β particles (such as americium-241, strontium-90, and plutonium-238, etc.) will cause radiation damage to the battery. In addition, considering the working life and commercial needs of the battery, the half-life of the isotope radiation source is required to be more than 10 years, and it is easy to obtain and low in cost. The current more suitable isotope radiation source is tritium (average energy = 5.7 KeV, half-life 12.5 years). Since commercial tritium raw materials usually exist in the form of tritium gas, how to achieve efficient loading and utilization of tritium in the energy conversion matrix is ​​an urgent problem that needs to be solved. Chinese patent CN111446019A discloses a three-dimensional nanostructured tritium voltaic battery, which proposes to store tritiated metal in the gaps between the pores of the semiconductor grid frame, or to form a tritiated semiconductor by compounding tritium with a three-dimensional nanostructured semiconductor material. Chinese patent CN116435628A discloses a radiovoltaic-lithium battery, which proposes to load tritiated titanium in the gaps of a semiconductor nanorod array film. The above methods all use high-temperature and high-pressure physical methods to dissolve tritium in metals or semiconductors, which may cause changes in the physical and chemical properties of semiconductor energy conversion and storage matrix materials. In addition, the radius of tritium atoms is smaller than that of other atoms, and it is easy to migrate and diffuse in metals or semiconductors and cause escape problems. Therefore, how to reduce the impact of the loading process of tritium and the diffusion and migration of tritium on battery stability is another problem that needs to be solved. Summary of the invention

[0005] The purpose of the present invention is to solve the above problems in the prior art and provide a tritiated water-based zinc ion battery.

[0006] In order to achieve the above object, the present invention adopts the following technical scheme:

[0007] A tritium-water-based zinc ion battery comprises a positive electrode, a negative electrode, a diaphragm and an electrolyte; the electrolyte and the diaphragm are placed between the positive electrode and the negative electrode of the battery;

[0008] The positive electrode includes a current collector, a nanostructured semiconductor film, tritium water ( ) a radiation source, an active material and a conductive material; the nanostructured semiconductor film is prepared on a current collector; the active material and the conductive material are mixed and coated on the surface of the nanostructured semiconductor film to form a semiconductor heterojunction;

[0009] The tritium water radiation source exists in one or more of the following forms:

[0010] It exists in nanostructured semiconductor films in the form of crystalline tritiated water;

[0011] It exists in the active material in the form of crystallized tritiated water;

[0012] It exists in the electrolyte in the form of liquid tritium water; the electrolyte is an aqueous solution containing zinc ions.

[0013] The tritium water radiation source utilizes chemical hydrothermal synthesis technology to combine with atoms in nanostructured semiconductor thin films and / or active materials in the form of crystalline tritium water through coordination bonds or covalent bonds.

[0014] The tritiated water radiation source exists in the form of crystalline tritiated water in the crystal lattice of the nanostructured semiconductor film and / or the semiconductor active material to form lattice tritiated water.

[0015] The electrolyte is a mixed solution of one or more of zinc sulfate aqueous solution, zinc nitrate aqueous solution, zinc chloride aqueous solution, zinc acetate aqueous solution and zinc trifluoromethanesulfonate aqueous solution. The electrolyte may contain a tritium water radiation source, which can be used as a radiation source while meeting the performance of ion transport.

[0016] The nanostructured semiconductor film is a crystalline semiconductor film with a bandgap width greater than 2.3 eV, and the semiconductor material includes one or more of titanium dioxide, zinc oxide, zirconium dioxide, cadmium oxide, niobium pentoxide, cerium oxide, gallium trioxide, tin dioxide, tungsten trioxide, silicon carbide, gallium nitride, indium gallium nitrogen, gallium phosphide, indium nitride, aluminum nitride, aluminum phosphide, aluminum arsenide, molybdenum disulfide, cadmium sulfide, zinc sulfide, magnesium sulfide, zinc selenide, and magnesium selenide.

[0017] The three-dimensional nanostructure of the nanostructured semiconductor film is an ordered or disordered single crystal or polycrystalline thin film material composed of at least one basic structural unit of zero dimension, one dimension, or two dimension, and the thickness of the thin film material may be 1 to 500 μm; the basic structural units may include nanoparticles, nanowires, nanorods, nanocolumns, nanotubes, nanospheres, nanoflowers, nanosheets, etc.

[0018] The active material includes at least one of a layered compound or a porous compound, and has a bandgap of 1 eV to 5 eV.

[0019] The layered compound is one or more of vanadium pentoxide, vanadium dioxide, molybdenum disulfide, molybdenum sulfide, cadmium sulfide, molybdenum oxide, and tungsten oxide. Energy is stored and discharged through zinc ion deintercalation, and at the same time, it is used as a hole transport layer material to form a heterojunction with the semiconductor nanofilm, thereby enhancing the transport and separation of carriers, reducing the probability of carrier recombination, and improving the energy conversion efficiency of the betavoltaic battery.

[0020] The current collector is conductive glass, titanium foil, stainless steel foil, composite titanium foil, composite stainless steel foil and carbon cloth, etc.; the negative electrode is zinc foil or zinc alloy foil; and the diaphragm is a glass fiber diaphragm and a zeolite composite diaphragm.

[0021] The conductive material includes one or more carbon-based materials with large specific surface area selected from carbon nanotubes, graphene, carbon fibers, and conductive graphite particles. The use of the conductive material can improve the interfacial charge transport performance of the semiconductor nanoarray film layer and increase the electrochemical reaction sites. The carbon-based material can be a carbon-based material prepared from carbon-14, which can be used as a radiation source while meeting the conductive properties.

[0022] The present invention proposes a tritium-water-based zinc-ion battery that integrates a radiation unit and an energy storage unit in a battery structure, eliminating the ohmic loss caused by the connection of discrete devices from an external line, and does not require an additional energy management circuit (such as a boost circuit and an impedance matching circuit) to realize the trickle power generation of the radiation unit and the trickle charging of the energy storage unit at the same time. When the tritium-water radiation source integrated in the battery itself radiates high-energy β particles, the isotope radiation energy can be continuously converted into electrical energy through the semiconductor heterojunction in the radiation unit, and then the zinc ions are released from the semiconductor active material through the reduction reaction of the zinc ions in the energy storage unit, realizing the conversion and storage of electrical energy into chemical energy. When driving an external load, the zinc ions are embedded in the active material through the oxidation reaction of the zinc ions in the energy storage unit, realizing the conversion of chemical energy into electrical energy, and the released electrical energy is used by external electronic devices. In this process, the battery realizes the trickle power generation of radiation energy and chemical energy storage, as well as high-power long-term discharge according to external needs. This integrated power generation and energy storage battery greatly compensates for the shortcomings of low trickle power generation and high output impedance of the radial battery, and can meet the application needs of electronic devices for high-power, maintenance-free and long-life power supplies in extreme environments.

[0023] Compared with the prior art, the technical solution of the present invention has the following beneficial effects:

[0024] The present invention utilizes chemical hydrothermal synthesis technology to combine tritium water in the form of crystallized tritium water with semiconductor atoms through coordination bonds or covalent bonds, or embeds it into the semiconductor lattice and combines it with the semiconductor in the form of lattice tritium water. Compared with the traditional high-temperature and high-pressure tritium treatment technology of metals or semiconductors, the tritium loading process does not affect the overall physical properties of the semiconductor material. At the same time, the chemical structure of tritium water is stable, and there is no problem of migration, diffusion and escape of tritium, which ensures the stability of the battery material.

[0025] The present invention uses a water-based electrolyte, which is not a crystalline structure, so there is no radiation damage problem, and has the advantages of being non-flammable and low in preparation cost, so the tritium water-based zinc ion battery of the present invention can achieve high capacity and long-term reliable operation. In addition, adding tritium water to the water-based electrolyte can be used as a radiation source.

[0026] The present invention can infiltrate the battery positive electrode material through the tritium water electrolyte, which not only significantly increases the interaction area between the tritium water and the nanostructured semiconductor material, but also significantly increases the effective area of ​​the solid-liquid interface and the corresponding in-situ ion exchange capacity. The direct benefit is to effectively improve the utilization efficiency of the tritium water radiation source and the efficiency of converting radiation energy into electrical energy by using the tritium voltage effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 This is a schematic diagram of the working principle of the radiation-voltaic water-based zinc ion battery in Example 1.

[0028] Figure 2 This is an electron microscope image of the nanostructured semiconductor film in Example 1.

[0029] Figure 3 For Example 1 Electron micrograph of the nanocomposite.

[0030] Figure 4 for Structural diagram.

[0031] Figure 5 For charging and discharging 1000 The charge and discharge cycle curves of the tritiated water-based zinc ion battery prepared in Example 1 and the battery without tritiated water under current density.

[0032] Figure 6 The relationship between the battery voltage and time when the tritiated water-based zinc ion battery prepared in Example 1 was subjected to a discharge-trickle charge-discharge experiment. DETAILED DESCRIPTION

[0033] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention clearer and more understandable, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments.

[0034] Example 1

[0035] The tritiated water-based zinc ion battery described in this embodiment includes a battery positive electrode, an electrolyte, a separator and a battery negative electrode, wherein the battery positive electrode includes a current collector, a nanostructured semiconductor film, a tritiated water radiation source, an active material and a conductive material.

[0036] Specifically, the material of the current collector is aluminum-doped zinc oxide (AZO) conductive glass; the negative electrode of the battery is a zinc (Zn) sheet; and the separator is glass fiber;

[0037] The nanostructured semiconductor film is a wide-bandgap semiconductor zinc oxide nanorod array (ZRNAs) film, which is formed by vertically growing a plurality of zinc oxide (ZnO) nanorods on AZO conductive glass;

[0038] The tritium water radiation source is present in the form of crystalline tritium water in vanadium dioxide ( ) molecular layers, forming tritium hydrated vanadium dioxide compounds ( );

[0039] The active material is carbon-coated vanadium dioxide ( ) nanocomposite; the conductive material is carbon black or SWCNTs, the The slurry prepared by mixing the nanocomposite with the conductive material carbon black is coated on the surface of the ZNRAs film to form a The positive electrode of the battery structure.

[0040] The specific working principle of the radiation water-based zinc ion battery is as follows Figure 1 shown.

[0041] Tritium water radiation source Emitted beta particles and ZNRAs and VO 2 The collision excites a large number of electron-hole pairs. These excited electron-hole pairs are The built-in electric field of the heterojunction separates the excited electrons from the VO 2 The conduction band of ZnO migrates to the conduction band of ZnO, then migrates to the AZO current collector, and finally migrates to the Zn negative electrode through the external circuit. At the same time, the excited holes migrate from the valence band of ZnO to VO 2 valence band, these migrated holes and VO 2 The holes excited in the Zinc ions in the layered structure ( ) to break away. The electrolyte passes through the glass fiber diaphragm and obtains electrons on the Zn negative electrode, which is reduced to Zn and deposited on the Zn negative electrode. In this process, the transformation from radiation energy → electrical energy → chemical energy is completed, realizing the process of radiation energy trickle power generation and chemical energy storage.

[0042] The preparation method of the radiovoltaic water-based zinc ion battery described in this embodiment comprises the following steps:

[0043] 1) Preparation of ZRNAs film: AZO conductive glass was ultrasonically cleaned in a mixed solution of isopropanol, ethanol and acetone (1:1:1) for 1 h, and a growth solution was prepared with 0.05 M zinc nitrate hexahydrate, 0.05 M hexamethyltetramine, 0.02 M polyetherimide and deionized water. Then, AZO conductive glass was placed in the growth solution, and ZRNAs film was prepared by a hydrothermal synthesis process in a reactor. The morphology was as follows: Figure 2As shown. According to the reaction time, the diameter of the prepared ZnO nanorods can be controlled to be 100 nm to 5 μm, and the rod length can be 100 nm to 20 μm. The prepared ZRNAs film samples are placed in an inert atmosphere or a hydrogen atmosphere for high temperature annealing.

[0044] 2) Preparation of nanocomposites: 3 mmol The powder was added to 30 ml of deionized water and stirred for 10 min. 1 mmol of glucose was added to the solution and stirred for 10 min. Finally, a small amount of tritium water was added and stirred for 10 min until the solution was uniformly dispersed. Subsequently, the uniformly dispersed solution was placed in a stainless steel reactor and heated at 180 °C for 24 h to obtain Nanocomposites, morphology such as Figure 3 As shown, Molecular structure diagram Figure 4 shown.

[0045] 3) The nanocomposite, conductive material carbon black and binder polyvinylidene fluoride (PVDF) were mixed in a mass ratio of 8:1:1, and N-methylpyrrolidone (NMP) was added to form a slurry with uniform color and good fluidity. Then, it was evenly coated on the ZRNAs film by a coater. It was then moved to a vacuum drying oven at 120°C and dried for more than 12 hours. Finally, the sample was transferred to a vacuum drying oven at 80°C and dried for use.

[0046] 4) Preparation of water-based electrolyte: Dissolve 0.3 mol zinc trifluoromethanesulfonate powder in 100 mL of deionized water, stir magnetically for 30 min until the solution is clear, and bottle the electrolyte for later use.

[0047] In other embodiments, tritium water can be added to a water-based electrolyte to prepare a tritium water electrolyte. Heterojunction excited electron-hole pairs, and the transport mechanism of charge carriers and ions Figure 1 The working mechanism is the same.

[0048] 5) Battery packaging: The radiation water-based zinc ion battery is packaged in a CR2032 button cell structure; The positive electrode of the battery with the structure is assembled in the positive electrode shell of the button battery, and then the Zn negative electrode is equipped in the negative electrode shell, and the shell and the electrode structure are electrically connected through the conductive silver paste. The water-based electrolyte is dripped into the positive electrode shell of the battery, and then the glass fiber diaphragm, spring gasket and negative electrode shell are assembled in sequence to complete the battery packaging and test.

[0049] Test results: First, the performance of the tritium water-based zinc ion battery was tested using a battery capacity tester. In order to compare the effect of the tritium water radiation source on the battery performance, the same battery was prepared using non-radioactive water instead of tritium water in preparation step 2). The battery was charged and discharged using a specific current of 1000 mA / g. The test results are as follows: Figure 5 As shown in the figure, it can be seen that before and after the addition of tritium water, the charge and discharge capacity of the battery increased from 242 mAh / g to 259 mAh / g, and the capacity increased by about 7%. Then, a trickle charge test was carried out on the battery loaded with tritium water in Example 1. Figure 6 As shown. Before the test, the battery voltage was discharged to 0.5 V at 3 mA / g, and then the battery voltage rose from 0.5 V to 0.8 V after 82 hours without external charging current. The battery was then discharged at 3 mA / g for 40 hours, and the battery voltage dropped from 0.8 V to 0.5 V. The battery discharge energy was calculated to reach 28 μW. This discharge energy can be roughly regarded as the energy of the tritium-volt water-based zinc-ion battery using the tritium-volt effect to convert radiation energy into electrical energy. The test results directly prove the effectiveness of the tritium-volt water-based zinc-ion battery.

Claims

1. A tritiated water-based zinc ion battery, comprising a positive electrode, a negative electrode and an electrolyte, characterized in that: The positive electrode comprises a current collector, a nanostructured semiconductor film, a tritium water radiation source, an active material and a conductive material; the nanostructured semiconductor film is prepared on the current collector; the active material is mixed with the conductive material and coated on the surface of the nanostructured semiconductor film to form a semiconductor heterojunction; the tritium water radiation source exists in one or more of the following forms: in the form of crystallized tritium water in the nanostructured semiconductor film; in the form of crystallized tritium water in the active material; It exists in the electrolyte in the form of liquid tritium water; the electrolyte is an aqueous solution containing zinc ions.

2. A tritiated water-based zinc ion battery as claimed in claim 1, characterized in that: The tritium water radiation source utilizes chemical hydrothermal synthesis technology to combine with atoms in nanostructured semiconductor thin films and / or active materials in the form of crystalline tritium water through coordination bonds or covalent bonds.

3. A tritiated water-based zinc ion battery as claimed in claim 1, characterized in that: The tritiated water radiation source exists in the form of crystalline tritiated water in the crystal lattice of the nanostructured semiconductor film and / or the semiconductor active material to form lattice tritiated water.

4. A tritiated water-based zinc ion battery as claimed in claim 1, characterized in that: The electrolyte is a mixed solution of one or more of a zinc sulfate aqueous solution, a zinc nitrate aqueous solution, a zinc chloride aqueous solution, a zinc acetate aqueous solution and a zinc trifluoromethanesulfonate aqueous solution.

5. A tritiated water-based zinc ion battery as claimed in claim 1, characterized in that: The nanostructured semiconductor film is a crystalline semiconductor film with a bandgap width greater than 2.3 eV, and the semiconductor material includes one or more of titanium dioxide, zinc oxide, zirconium dioxide, cadmium oxide, niobium pentoxide, cerium oxide, gallium trioxide, tin dioxide, tungsten trioxide, silicon carbide, gallium nitride, indium gallium nitrogen, gallium phosphide, indium nitride, aluminum nitride, aluminum phosphide, aluminum arsenide, molybdenum disulfide, cadmium sulfide, zinc sulfide, magnesium sulfide, zinc selenide, and magnesium selenide.

6. A tritiated water-based zinc ion battery as claimed in claim 1, characterized in that: The active material includes at least one of a layered compound or a porous compound, and has a bandgap of 1 eV to 5 eV.

7. A tritiated water-based zinc ion battery as claimed in claim 6, characterized in that: The layered compound is one or more of vanadium pentoxide, vanadium dioxide, molybdenum disulfide, molybdenum sulfide, cadmium sulfide, molybdenum oxide, and tungsten oxide.

8. A tritiated water-based zinc ion battery as claimed in claim 1, characterized in that: The negative electrode is zinc foil or zinc alloy foil.

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