Low-temperature-resistant aqueous zinc-ion battery and preparation method thereof

Abstract

The application belongs to the technical field of aqueous zinc ion batteries, and discloses a low-temperature-resistant aqueous zinc ion battery and a preparation method thereof. The low-temperature-resistant aqueous zinc ion battery is constructed by using a single or composite positive electrode material with excellent zinc ion storage performance and ion diffusion dynamics, and using a composite aqueous solution system with various cations and anions combined and regulated as an electrolyte, and cooperating with zinc metal as a negative electrode. The low-temperature-resistant aqueous zinc ion battery is a low-temperature button type, soft package or cylindrical zinc ion battery. The application designs and regulates the interaction and hydrogen bond network distribution of various salt solutes and pure water solvents of the low-temperature-resistant electrolyte, matches the zinc storage positive electrode material with good ion dynamics in a low-temperature environment, and constructs the zinc ion battery with stable working capacity and high specific capacity at an extremely low temperature (‑80℃), which is applied as an energy supply device in various extreme environments.

Description

Technical Field

[0001] This invention belongs to the field of aqueous zinc-ion battery technology, and specifically relates to a low-temperature resistant aqueous zinc-ion battery and its preparation method. Background Technology

[0002] Aqueous zinc-ion batteries have emerged as a leading alternative energy storage system due to their environmental friendliness, safety, reliability, and low cost. Renewable energy sources (such as solar and wind power) exhibit significant geographical distribution and environmental variations (e.g., substantial temperature differences), making efficient energy storage a challenging problem. In low-temperature environments, aqueous electrolytes are prone to freezing, leading to decreased ionic conductivity and interfacial wettability, which in turn drastically deteriorates the electrochemical performance of aqueous zinc-ion batteries. Therefore, inhibiting electrolyte freezing is an effective way to improve the low-temperature failure of aqueous zinc-ion batteries. Currently, constructing aqueous zinc-ion batteries for extremely low-temperature environments (such as polar regions and space) still faces significant challenges. Existing reports mostly focus on improving performance through strategies such as preparing high-concentration electrolytes, hydrogels, and adding organic solvents (Nat. Commun. 2020, 11, 4463; Adv. Funct. Mater. 2020, 30, 1907218; Small 2021, 17, 2103195). However, these methods have drawbacks such as high cost, difficult preparation, and significant environmental pollution, making it difficult to meet the needs of practical applications. Summary of the Invention

[0003] In order to overcome the shortcomings and deficiencies of the aforementioned low-temperature aqueous zinc-ion batteries, the primary objective of this invention is to provide a low-cost, easy-to-prepare method for preparing an aqueous zinc-ion battery with ultra-low temperature tolerance and high ionic conductivity at low temperatures, and to effectively apply it to various extreme environmental scenarios.

[0004] The objective of this invention is achieved through the following solution:

[0005] A low-temperature resistant aqueous zinc-ion battery includes a positive electrode, a negative electrode, and a low-temperature resistant electrolyte;

[0006] The electrolyte in the low-temperature resistant electrolyte includes cations and anions, wherein the cation is Zn. 2+ It must contain at least one of rare earth element cations and alkali metal cations, and must contain Zn. 2+ The anion is a halide anion or a halide anion.

[0007] Preferably, the rare earth element cation is La. 3+ Ce 3+ At least one of the following; the alkali metal cation is Li + Na + K + 、Rb+ Cs + Mg 2+ Ca 2+ And Al 3+ At least one of them.

[0008] Preferably, the anion further includes acetate (CH3COO) - ), nitrate (NO3) - ), trifluoromethanesulfonate (CF3SO3) - ), tetrafluoroborate (BF4) - At least one of the following anions: ) and bis(trifluoromethanesulfonyl)imide (TFSI-);

[0009] More preferably, the anion is a combination of halide, halide anion and acetate, or a combination of halide, halide anion and nitrate, or a combination of halide, halide anion and tetrafluoroborate.

[0010] Preferably, the halide anion is at least one selected from ClO4-, BrO3-, and IO3-. The halide anion is F-, Cl-, or Br-. - At least one of the anions such as I-.

[0011] The concentration of the cation is 5–12 M, wherein Zn 2+ The concentration is 4-8M;

[0012] Preferably, when the anion is a combination of halide, halide anion and acetate, the concentration of halide is 2-12 M, the concentration of halide anion is 2-8 M, and the concentration of acetate is 0.5-2 M; when the anion is a combination of halide, halide anion and nitrate, the concentration of halide anion is 2-8 M, the concentration of halide anion is 4-8 M, and the concentration of nitrate is 1-4 M; when the anion is a combination of halide, halide anion and tetrafluoroborate, the concentration of halide is 2-12 M, the concentration of halide anion is 2-8 M, and the concentration of tetrafluoroborate is 0.5-1 M. When the anions are a combination of halide, halide anion, acetate, and tetrafluoroborate, the concentration of halide is 5–10 M, the concentration of halide anion is 4–8 M, the concentration of acetate is 0.2–0.8 M, and the concentration of tetrafluoroborate is 0.2–0.8 M. When the anions are a combination of halide, halide anion, nitrate, and tetrafluoroborate, the concentration of halide is 5–10 M, the concentration of halide anion is 4–8 M, the concentration of nitrate is 0.8–1.2 M, and the concentration of tetrafluoroborate is 0.8–1.2 M.

[0013] The positive electrode is prepared by loading at least one of a conductive polymer, a coordination compound, a manganese-based compound, and a vanadium-based compound onto a substrate.

[0014] Preferably, the positive electrode has a porous, defective, or ion-pre-embedded structure;

[0015] Preferably, the conductive polymer is at least one of polyaniline (PANI), polypyrrole (PPy), and polythiophene (PEDOT); the coordination compound is at least one of Prussian blue (PB) and its analogues (PBA) and a conductive MOF; more preferably, the Prussian blue analogue is at least one of cobalt PBA, manganese PBA, iron-cobalt PBA, iron-zinc PBA, iron-copper PBA, and iron-nickel PBA; the conductive MOF is at least one of Ni-CAT and Co-CAT; the manganese-based compound is at least one of manganese dioxide, manganese trioxide, manganese tetroxide, zinc manganate, magnesium manganate, lithium manganate, and sodium manganate; the vanadium-based compound is at least one of vanadium dioxide, vanadium pentoxide, vanadium dodecoxide, vanadium tridecoxide, zinc vanadate, lithium vanadate, sodium vanadate, magnesium vanadate, calcium vanadate, ammonium vanadate, potassium vanadate, basic zinc vanadate, sodium vanadium phosphate, lithium vanadium phosphate, and sodium vanadium fluoride.

[0016] Preferably, the substrate is titanium foil, stainless steel foil, carbon paper, or carbon cloth.

[0017] Preferably, the loading of at least one of the conductive polymer, coordination compound, manganese-based compound, and vanadium-based compound on the matrix is ​​2-20 mg / cm³. -2 The electrode thickness is between 0.1-2.0 mm, and the tap density is 0.5-3 g / cm³. 3

[0018] Preferably, the loading method includes in-situ polymerization, electrochemical deposition, or hydrothermal synthesis.

[0019] More preferably, the positive electrode is prepared by oxidative polymerization of a conductive polymer on carbon paper; or by using PVDF or PTFE as a binder and carbon black or Super P as a conductive agent, with the mass ratio of the positive electrode active material to the binder and conductive agent being (7-8):(1-2):1. The material is uniformly ground into a slurry using NMP as a solvent and coated at a speed of 1-10 m / min. The positive electrode can be cut into circular, rectangular, and various other desired shapes as needed. The positive electrode active material is at least one of a conductive polymer, a coordination compound, a manganese-based compound, and a vanadium-based compound.

[0020] The negative electrode is high-purity zinc foil, or it can be obtained by anodic deposition or brushing zinc paste onto commonly used substrates, including titanium foil, stainless steel foil, carbon paper, carbon cloth, etc.

[0021] A method for preparing a low-temperature resistant aqueous zinc-ion battery includes the following steps: assembling the prepared positive electrode, low-temperature resistant electrolyte and cathode into an aqueous zinc-ion battery.

[0022] Preferably, the method specifically involves using glass fiber as a separator, encapsulating a button cell with a standard button shell under a pressure of 60-80 MPa, and adding 50-100 μL of low-temperature resistant electrolyte; encapsulating a cylindrical cell with alternating wound electrodes, and adding 2-3 mL of low-temperature resistant electrolyte; and encapsulating 50-200 layers of active electrodes with an aluminum-plastic film to form a soft-pack cell, with adding 1-2 mL of low-temperature resistant electrolyte.

[0023] The low-temperature resistant aqueous zinc-ion battery can operate normally at temperatures ranging from -80℃ to 35℃.

[0024] This invention designs an electrolyte that is resistant to low temperatures and weak chemical corrosion. It selects suitable combinations of salts containing multiple cations and anions, dissolved together in water, with Zn... 2+ As the main cation, various alkali metal element cations, Mg, are introduced. 2+ Ca 2+ Al 3+ One or more of rare earth element cations, with halogenated ions (such as ClO4) - BrO3 - IO3 - A mixture of halogen anions and halogen anions is used as the main anion, while acetate (CH3COO) is introduced. - ), nitrate (NO3) - ), trifluoromethanesulfonate (CF3SO3) - ), tetrafluoroborate (BF4) - ), bis(trifluoromethanesulfonyl)imide (TFSI) - Anions were added, and the combination and ratio of various cations and anions were adjusted. The prepared electrolyte had a stable pH of 4-6 and an ionic conductivity of 152.1 mS / cm at room temperature. -1 The ionic conductivity at -40℃ is 16.1 mS / cm. -1 The ionic conductivity at a low temperature of -70℃ is 3.53 mS / cm. -1 The ionic conductivity remains at 2.35 mS / cm even at a low temperature of -80℃. -1 .

[0025] The prepared positive electrode, negative electrode, optimized electrolyte, and glass fiber separator are assembled to form a button or pouch zinc-ion battery device, achieving a specific capacity of 86 mAh g at -70℃. -1 , using 1A g -1The current density exhibits no capacity decay after 5000 charge-discharge cycles; the specific capacity reaches 74 mAh g at -80℃. -1 , using 1A g -1 The current density maintains more than 85% of the capacity after 1200 charge-discharge cycles.

[0026] The mechanism of this invention is as follows: For the electrolyte, various cations with small ionic radii act as hydrogen bond donors, bonding with O atoms in water molecules through strong electrostatic attraction to form stable hydrated ions. Anions, with a stronger ability to disrupt the water molecule structure, act as hydrogen bond acceptors, forming hydrogen bonds with H atoms in water molecules. By screening the most suitable combination of cations and anions, the hydrogen bond network of water molecules can be effectively broken synergistically, lowering the freezing point and achieving excellent antifreeze performance. For the cathode material, by constructing porous, defective, and pre-embedded structures, the diffusion kinetics of ions under low-temperature conditions can be effectively improved, the activation energy of the reaction can be reduced, and the desolvation process can be ensured smoothly and efficiently, thereby guaranteeing the energy storage capacity and cycle stability. The above-mentioned methods for designing electrolytes and electrode materials are of great significance for designing low-temperature resistant aqueous zinc-ion batteries. Attached Figure Description

[0027] Figure 1 A schematic diagram of the structure of an ultra-low temperature zinc-ion battery.

[0028] Figure 2 Temperature rate performance of ultra-low temperature zinc-ion batteries (Example 1).

[0029] Figure 3 Charge-discharge cycle performance of ultra-low temperature zinc-ion batteries at -70°C (Example 1).

[0030] Figure 4 Charge-discharge cycle performance of ultra-low temperature zinc-ion batteries at -80°C (Example 1).

[0031] Figure 5 Charge-discharge curves of an ultra-low temperature zinc-ion battery charged at 27°C and discharged at -60°C (Example 1).

[0032] Figure 6 Charge-discharge curves of an ultra-low temperature zinc-ion battery charged at 27°C and discharged at -80°C (Example 1).

[0033] Figure 7 Charge-discharge cycle performance of ultra-low temperature zinc-ion batteries at -70°C (Example 2).

[0034] Figure 8 Charge-discharge cycle performance of ultra-low temperature zinc-ion batteries at -70°C (Example 3).

[0035] Figure 9 Charge-discharge cycle performance of ultra-low temperature zinc-ion batteries at -80°C (Example 3).

[0036] Figure 10 Charge-discharge cycle performance of ultra-low temperature zinc-ion batteries at -70°C (Example 4).

[0037] Figure 11 Charge-discharge cycle performance of ultra-low temperature zinc-ion batteries at -70°C (Example 5).

[0038] Figure 12 Charge-discharge cycle performance of ultra-low temperature zinc-ion batteries at -80°C (Example 5).

[0039] Figure 13 Charge-discharge cycle performance of ultra-low temperature zinc-ion batteries at -70°C (Example 6).

[0040] Figure 14 Charge-discharge cycle performance of ultra-low temperature zinc-ion batteries at -70°C (Example 7). Detailed Implementation

[0041] The present invention will be further described in detail below with reference to the embodiments and accompanying drawings, but the implementation of the present invention is not limited thereto.

[0042] Example 1

[0043] A schematic diagram of the structure of an ultra-low temperature aqueous zinc-ion battery is shown below. Figure 1 As shown, it includes a zinc-storing positive electrode material, a zinc metal negative electrode, and a low-temperature resistant electrolyte.

[0044] Preparation process of zinc storage cathode material:

[0045] The conductive carbon paper substrate was washed and immersed in a precursor solution containing conductive polymer monomers in an ice bath environment at 0°C for polymerization growth. The aniline monomer concentration was 0.27M, dispersed in a 1M HCl solution. Ammonium persulfate was slowly added as an oxidant to initiate the polymerization reaction until the system concentration reached 67.7mM. After stirring continuously for 2 hours, the grown electrode material was removed, washed, and dried for later use. The polyaniline loading on the substrate was 3-5 mg / cm³. -2 .

[0046] The process of preparing and regulating low-temperature resistant electrolyte:

[0047] Using distilled water as a solvent, a mixed solution of 4M Zn(ClO4)2 and 2M ZnCl2 was first prepared. Then, Ce(CH3COO)3 and RbBr2 were added to prepare a concentration of 0.5M, respectively, to obtain a low-temperature resistant aqueous electrolyte.

[0048] The cathode material, low-temperature resistant electrolyte, and commercial zinc foil prepared above were assembled into a coin-type aqueous zinc-ion battery, exhibiting excellent low-temperature energy storage performance and superior variable-rate performance. The capacity remained above 60% even when the temperature dropped from room temperature to -55°C. Figure 2 As shown. The specific capacity can reach 86 mAh g at -70℃. -1 , using 1A g -1 The current density shows no capacity decay after 5000 charge-discharge cycles, such as... Figure 3 As shown; the specific capacity can reach 74 mAh g at -80℃. -1 , using 1A g -1 The current density maintains 85% capacity after 1200 charge-discharge cycles, such as Figure 4 As shown. At room temperature (27°C), 1A g... -1 When charged at a current density and discharged at -60°C, approximately 53% of the capacity can be retained. Figure 5 As shown. At room temperature (27°C), 1A g... -1 When charged at a current density and discharged at -80°C, approximately 27% of the capacity can be retained. Figure 6 As shown.

[0049] Example 2

[0050] Preparation process of zinc storage cathode material:

[0051] The conductive carbon paper substrate was washed and immersed in a precursor solution containing conductive polymer monomers in an ice bath environment at 0°C for polymerization growth. The aniline monomer concentration was 0.27M, dispersed in a 1M HCl solution. Potassium permanganate was slowly added as an oxidant to simultaneously initiate the polymerization of the conductive polymer and the growth of manganese dioxide, with a total amount used reaching 50mM. After stirring continuously for 2.5 hours, the grown electrode material was removed, washed, and dried for later use. The polyaniline loading on the substrate was 3-5 mg / cm³. -2 .

[0052] The process of preparing and regulating low-temperature resistant electrolyte:

[0053] Using distilled water as a solvent, a mixed solution of 3M Zn(BrO3)2 and 3M ZnI2 was first prepared. Then, La(NO3)3 and CsCl were added to prepare a concentration of 1M to obtain a low-temperature resistant aqueous electrolyte.

[0054] The above-prepared cathode material, low-temperature resistant electrolyte, and commercial zinc foil were assembled into a coin-type aqueous zinc-ion battery, achieving a specific capacity of 90 mAh g at -70℃. -1 , using 0.5A g -1 The current density maintains 94% capacity after 2000 charge-discharge cycles, such as Figure 7 As shown.

[0055] Example 3

[0056] Preparation process of zinc storage cathode material:

[0057] The conductive carbon paper substrate was washed and immersed in a precursor solution containing conductive polymer monomers in an ice bath at 0°C for polymerization growth. The pyrrole monomer concentration was 0.27M, dispersed in a 1M HCl solution. Ammonium persulfate was slowly added as an oxidant to initiate the polymerization reaction until the system concentration reached 67.7mM. After stirring continuously for 2 hours, the grown electrode material was removed, washed, and dried for later use. The polypyrrole loading on the substrate was 3-5 mg / cm³. -2 .

[0058] The process of preparing and regulating low-temperature resistant electrolyte:

[0059] Using distilled water as a solvent, a mixed solution of 5M Zn(ClO4)2 and 1M ZnI2 was first prepared. Then, CH3COOK and MgBr2 were added to prepare a concentration of 0.8M to obtain a low-temperature resistant aqueous electrolyte.

[0060] The cathode material, low-temperature resistant electrolyte, and commercial zinc foil prepared above were assembled into a coin-type aqueous zinc-ion battery, which exhibits excellent low-temperature energy storage performance, with a specific capacity of up to 76 mAh g⁻¹ at -70°C. -1 , using 1A g -1 The current density shows no capacity decay after 3000 charge-discharge cycles, such as... Figure 8 As shown; the specific capacity can reach 62 mAh g at -80℃. -1 , using 1A g -1 The current density maintains 80% capacity after 1000 charge-discharge cycles, such as Figure 9 As shown.

[0061] Example 4

[0062] Preparation process of zinc storage cathode material:

[0063] The conductive carbon cloth substrate was washed and immersed in a precursor solution containing conductive polymer monomers, potassium ferricyanide, and ferric chloride in an ice bath environment at 0°C for polymerization growth. The aniline monomer concentration was 0.27M, and both potassium ferricyanide and ferric chloride were 50mM, dispersed in a 1M HCl solution. Ammonium persulfate was slowly added as an oxidant to initiate the polymerization reaction until the system concentration reached 67.7mM. After stirring continuously for 3 hours, the grown electrode material was removed, washed, and dried for later use. The polyaniline loading on the substrate was 3-5 mg / cm³. -2 .

[0064] The process of preparing and regulating low-temperature resistant electrolyte:

[0065] Using distilled water as a solvent, a mixed solution of 3M Zn(IO3)2 and 3M ZnCl2 was first prepared. Then, CH3COONa and CsI were added to prepare a concentration of 1.5M to obtain a low-temperature resistant aqueous electrolyte.

[0066] The cathode material, low-temperature resistant electrolyte, and commercial zinc foil prepared above were assembled into a coin-type aqueous zinc-ion battery, which exhibits excellent low-temperature energy storage performance, with a specific capacity of up to 96 mAh g⁻¹ at -70°C. -1 , using 1A g -1 The current density maintains 96% capacity after 2500 charge-discharge cycles, such as Figure 10 As shown.

[0067] Example 5

[0068] Preparation process of zinc storage cathode material:

[0069] The conductive carbon cloth substrate was cleaned, and at room temperature, a substrate of appropriate size was immersed in a precursor solution containing conductive polymer monomers and manganese-based compounds for stepwise electrodeposition. First, polypyrrole material was loaded onto the substrate using a constant current method. The precursor solution contained 0.1 M pyrrole monomers dispersed in a 1 M HCl solution. A 1 mA cm⁻¹ current was used for the electrodeposition. -2 Deposition at current density for 30 minutes yielded a loading of 2-3 mg / cm³. -2 Subsequently, the polypyrrole-loaded electrode was placed in a precursor solution of 0.1 M manganese acetate and 0.1 M sodium sulfate, and subjected to an amplitude of 5 mA cm⁻¹. -2 Deposition at current density for 20 minutes yielded a manganese dioxide loading of 4-5 mg / cm³. -2 Remove the deposited electrode material, wash and dry it for later use.

[0070] The process of preparing and regulating low-temperature resistant electrolyte:

[0071] Using distilled water as a solvent, a mixed solution of 4M Zn(ClO4)2 and 3M ZnBr2 was first prepared. Then, CH3COOK and CsBF4 were added to prepare a concentration of 0.5M to obtain a low-temperature resistant aqueous electrolyte.

[0072] The cathode material, low-temperature resistant electrolyte, and commercial zinc foil prepared above were assembled into a coin-type aqueous zinc-ion battery, which exhibits excellent low-temperature energy storage performance, with a specific capacity of up to 105 mAh g⁻¹ at -70°C. -1 , using 1A g -1 The current density maintains 94% capacity after 2000 charge-discharge cycles, such as Figure 11 As shown. The specific capacity can reach 75 mAh g at -80℃. -1, using 1A g -1 The current density maintains 80% capacity after 1400 charge-discharge cycles, such as Figure 12 As shown.

[0073] Example 6

[0074] Preparation process of zinc storage cathode material:

[0075] The conductive titanium substrate was cleaned. Commercial vanadium trioxide, conductive carbon black, and PVDF binder were uniformly ground in an 8:1:1 ratio to form a homogeneous slurry with suitable viscosity. This slurry was then brushed onto the cleaned substrates and vacuum dried. The active material was oxidized using a constant current method. The dried electrode material was placed in a 1M ZnSO4 electrolyte, with zinc foil as the negative electrode, and an electrode was applied at 1 mA cm⁻¹ in a two-electrode mode. -2 The electrode material was subjected to oxidation treatment at a current density until the voltage between the electrodes reached 1.4V. The treated electrode material was then removed, washed, and dried for later use. The polymer loading on the matrix was 3-5 mg / cm³. -2 .

[0076] The process of preparing and regulating low-temperature resistant electrolyte:

[0077] Using distilled water as a solvent, a mixed solution of 2M Zn(ClO4)2 and 3M ZnCl2 was first prepared. Then, Mg(NO3)2 and NaBF4 were added to prepare a concentration of 1M to obtain a low-temperature resistant aqueous electrolyte.

[0078] The cathode material, low-temperature resistant electrolyte, and commercial zinc foil prepared above were assembled into a coin-type aqueous zinc-ion battery, which exhibits excellent low-temperature energy storage performance, with a specific capacity of up to 75 mAh g⁻¹ at -70°C. -1 , using 1A g -1 The current density maintains 92% capacity after 3000 charge-discharge cycles, such as Figure 13 As shown.

[0079] Example 7

[0080] Preparation process of zinc storage cathode material:

[0081] The conductive carbon cloth substrate was washed and a substrate of appropriate size was immersed in a precursor solution containing conductive MOF for chemical bath polymerization growth. The precursor solution contained 10 mg of Ni(OAc)₂·4H₂O, 7 mg of HHTP, and 4 mL of deionized water. The reaction was carried out at 85 °C for 4 h. After the reaction was completed, the resulting dark blue electrode was removed, washed with deionized water, and dried for later use. The polymer loading on the substrate was 3-5 mg cm⁻¹. -2 .

[0082] The process of preparing and regulating low-temperature resistant electrolyte:

[0083] Using distilled water as a solvent, a mixed solution of 3M Zn(ClO4)2 and 2M ZnI2 was first prepared. Then, LiClO4 and NaI were added to prepare a concentration of 1.5M to obtain a low-temperature resistant aqueous electrolyte.

[0084] The cathode material, low-temperature resistant electrolyte, and commercial zinc foil prepared above were assembled into a coin-type aqueous zinc-ion battery, which exhibits excellent low-temperature energy storage performance, with a specific capacity of up to 84 mAh g⁻¹ at -70°C. -1 , using 1A g -1 The current density maintains 90% capacity after 2800 charge-discharge cycles, such as Figure 14 As shown.

[0085] Comparative Example 1

[0086] Preparation process of zinc storage cathode material:

[0087] The conductive carbon paper substrate was washed and immersed in a precursor solution containing conductive polymer monomers in an ice bath at 0°C for polymerization growth. The aniline monomer concentration was 0.27M, dispersed in a 1M HCl solution. Ammonium persulfate was slowly added as an oxidant to initiate the polymerization reaction until the system concentration reached 67.7mM. After stirring continuously for 2 hours, the grown electrode material was removed, washed, and dried for later use. The polymer loading on the substrate was 3-5 mg / cm³. -2 .

[0088] The process of preparing and regulating low-temperature resistant electrolyte:

[0089] Using distilled water as a solvent, 4M Zn(ClO4)2 was first prepared, and then Zn(CH3COO)2 was added to prepare a concentration of 0.5M to obtain a low-temperature resistant aqueous electrolyte.

[0090] The cathode material, low-temperature resistant electrolyte, and commercial zinc foil prepared above were assembled into a coin-type aqueous zinc-ion battery, exhibiting excellent low-temperature energy storage performance. However, its capacity remained at only 35% of its pre-load capacity as the temperature decreased from room temperature to -50°C. At -70°C, the specific capacity dropped to a mere 5 mAh g⁻¹. -1 The specific capacity is 0 at -80℃.

[0091] Comparative Example 2

[0092] Preparation process of zinc storage cathode material:

[0093] Conductive substrates such as carbon paper, carbon cloth, and titanium sheets are cleaned and immersed in a precursor solution containing conductive polymer monomers in an ice bath environment at 0°C for polymerization growth. The aniline monomer concentration is 0.27M, dispersed in a 1M HCl solution. Ammonium persulfate is slowly added as an oxidant to initiate the polymerization reaction until the system concentration reaches 67.7mM. After stirring continuously for 2 hours, the grown electrode material is removed, cleaned, and dried for later use. The polymer loading on the substrate is 3-5 mg / cm³. -2 .

[0094] The process of preparing and regulating low-temperature resistant electrolyte:

[0095] Using distilled water as a solvent, a mixed solution of 4M Zn(ClO4)2 and 1M ZnCl2 was first prepared. Then, KClO4 and LiCl were added to prepare solutions with a concentration of 0.5M, thus obtaining a low-temperature resistant aqueous electrolyte.

[0096] The cathode material, low-temperature resistant electrolyte, and commercial zinc foil prepared above were assembled into a coin-type aqueous zinc-ion battery, exhibiting excellent low-temperature energy storage performance and superior variable-rate performance, retaining approximately 40% of its capacity even when cooled from room temperature to -55°C. The specific capacity at -70°C was 23 mAh g⁻¹. -1 , using 1A g -1 The current density is such that after 500 charge-discharge cycles, the capacity decays to 60% of the initial value; the specific capacity is 0 at -80℃.

Claims

1. A low-temperature resistant aqueous zinc-ion battery, characterized in that... Includes positive electrode, negative electrode, and low-temperature resistant electrolyte; The electrolyte in the low-temperature resistant electrolyte includes cations and anions, wherein the cation is Zn. 2+ And rare earth element cations and / or alkali metal element cations; the rare earth element cation is La. 3+ Ce 3+ At least one of the following; the alkali metal cation is Li + Na + K + 、Rb + Cs + Mg 2+ Ca 2+ At least one of the following; the concentration of the alkali metal cation is 5-12 M, wherein Zn 2+ The concentration is 4-8 M; The anion is a halide anion and a halide anion; the halide anion is ClO4. - BrO3 - and IO3 - At least one of the following; the halide anion is F - Cl - ,Br - and I - At least one of them; The anion also includes at least one of acetate, nitrate, trifluoromethanesulfonate, tetrafluoroborate, and bis(trifluoromethanesulfonyl)imide anions; When the anions are a combination of halide, halide anion and acetate, the concentration of halide is 2-12 M, the concentration of halide anion is 2-8 M, and the concentration of acetate is 0.5-2 M. When the anions are a combination of halide, halide and nitrate, the concentration of halide anions is 2-8 M, the concentration of halogen anions is 4-8 M, and the concentration of nitrate is 1-4 M. When the anions are a combination of halide, halide anion and tetrafluoroborate, the concentration of halide is 2-12 M, the concentration of halide anion is 2-8 M, and the concentration of tetrafluoroborate is 0.5-1 M. When the anions are a combination of halide, halide anion, acetate and tetrafluoroborate, the concentration of halide is 5-10 M, the concentration of halide anion is 4-8 M, the concentration of acetate is 0.2-0.8 M, and the concentration of tetrafluoroborate is 0.2-0.8 M. When the anions are a combination of halide, halide anion, nitrate and tetrafluoroborate, the concentration of halide is 5-10 M, the concentration of halide anion is 4-8 M, the concentration of nitrate is 0.8-1.2 M, and the concentration of tetrafluoroborate is 0.8-1.2 M.

2. The low-temperature resistant aqueous zinc-ion battery according to claim 1, characterized in that: The positive electrode is prepared by loading an active material onto a substrate, wherein the active material is at least one of a conductive polymer, a coordination compound, a manganese-based compound, and a vanadium-based compound; the negative electrode is a high-purity zinc foil, or a negative electrode is obtained by anodic deposition or brushing zinc paste onto a substrate, wherein the substrate is at least one of a titanium foil, a stainless steel foil, a carbon paper, and a carbon cloth substrate.

3. The low-temperature resistant aqueous zinc-ion battery according to claim 2, characterized in that: The loading of the active material on the matrix is ​​2-20 mg / cm³. -2 The electrode thickness is 0.1-2.0 mm, and the tap density is 0.5-3 g / cm³. 3 PVDF or PTFE is used as a binder, and carbon black or Super P is used as a conductive agent. The mass ratio of active material, binder and conductive agent is (7~8):(1~2):

1. NMP is used as a solvent to grind the active material, binder and conductive agent into a slurry. The slurry is then coated at a speed of 1-10 m / min to obtain a positive electrode with well-adhered active material. The electrode is then cut into the required shape as needed.

4. The low-temperature resistant aqueous zinc-ion battery according to claim 2, characterized in that: The conductive polymer is at least one of polyaniline, polypyrrole, and polythiophene; the coordination compound is at least one of Prussian blue and conductive MOF; the manganese-based compound is at least one of manganese dioxide, manganese trioxide, manganese tetroxide, zinc manganate, magnesium manganate, lithium manganate, and sodium manganate; the vanadium-based compound is at least one of vanadium dioxide, vanadium pentoxide, vanadium dodecyl oxide, vanadium hexadecyl oxide, zinc vanadate, lithium vanadate, sodium vanadate, magnesium vanadate, calcium vanadate, ammonium vanadate, potassium vanadate, basic zinc vanadate, sodium vanadium phosphate, lithium vanadium phosphate, and sodium vanadium fluorophosphate.

5. A method for preparing a low-temperature resistant aqueous zinc-ion battery according to any one of claims 1 to 4, characterized in that: A water-based zinc-ion battery is assembled from a positive electrode, a low-temperature resistant electrolyte, and a negative electrode.

6. The method according to claim 5, characterized in that... The method is specifically as follows: Using glass fiber as the separator, the standard button shell is used to encapsulate the button cell under a pressure of 60-80 MPa, and the amount of low-temperature resistant electrolyte added is 50-100 μL; Alternatively, cylindrical batteries can be encapsulated by alternately winding electrodes, with a low-temperature electrolyte addition of 2-3 mL. Alternatively, an aluminum-plastic film can be used to encapsulate 50-200 layers of active electrodes to form a soft-pack battery, with a low-temperature electrolyte addition of 1-2 mL.

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