Eutectic electrolyte for improving low-temperature performance of nickel-zinc battery

Abstract

This application discloses a eutectic electrolyte for improving the low-temperature performance of nickel-zinc batteries, belonging to the field of nickel-zinc battery electrolyte technology. The eutectic electrolyte comprises a 6-8 mol / L KOH aqueous solution and 1-5% by mass of eutectic electrolyte additives. The additives consist of hydrogen bond donors, hydrogen bond acceptors, and functional regulators in a molar ratio of (2-4):(1-2):(0.1-0.5), wherein the hydrogen bond donors are sulfonamide compounds, the hydrogen bond acceptors are amphoteric surfactants, and the functional regulators are metal ion complexing agents and / or corrosion inhibitors. This application constructs a ternary composite eutectic system, forming a multi-level cross-linked hydrogen bond network in the alkaline electrolyte, achieving synergistic optimization of antifreeze properties, ion conductivity, and zinc anode protection. Nickel-zinc batteries using this electrolyte exhibit an ionic conductivity ≥10 mS / cm at -40℃ and a capacity retention rate ≥85% after 500 cycles, making it suitable for low-temperature energy storage and emergency power applications.

Description

Technical Field

[0001] This invention belongs to the field of nickel-zinc battery electrolyte technology, specifically relating to a eutectic electrolyte for improving the low-temperature performance of nickel-zinc batteries and its preparation method, as well as nickel-zinc batteries containing the electrolyte and their application in low-temperature environments. Background Technology

[0002] Nickel-zinc batteries, as a new type of rechargeable battery, have significant advantages such as high energy density, fast charge and discharge rates, environmental friendliness, and low cost. Compared with lead-acid and nickel-cadmium batteries, they have broad application prospects in portable devices, energy storage systems, and other scenarios. However, nickel-zinc batteries suffer from severe performance degradation in low-temperature environments (typically below -10°C), which greatly limits their widespread application in cold regions and low-temperature special scenarios.

[0003] At low temperatures, nickel-zinc battery electrolytes are prone to solidification and increased viscosity, leading to a significant decrease in ion migration rate and increased charge transfer resistance at the electrode / electrolyte interface. Simultaneously, the zinc anode is susceptible to dendrite growth, passivation, and corrosion, exacerbating hydrogen evolution side reactions, further reducing battery charge / discharge efficiency, shortening cycle life, and even causing battery failure. Currently, the main methods to improve the low-temperature performance of nickel-zinc batteries include optimizing electrolyte concentration and adding single antifreeze agents or corrosion inhibitors. However, existing technologies have significant shortcomings: while single antifreeze agents can lower the electrolyte freezing point, they sacrifice ionic conductivity; single corrosion inhibitors can only alleviate zinc anode corrosion and cannot solve the problem of insufficient ion migration efficiency at low temperatures; and most additives have poor stability in the alkaline electrolyte system of nickel-zinc batteries, easily decomposing and making it difficult to achieve a synergistic improvement in low-temperature performance and battery cycle stability.

[0004] Eutectic systems have attracted widespread attention in the field of electrolyte additives due to their unique characteristics such as low freezing point and high stability. However, when applying eutectic systems to optimize the low-temperature performance of nickel-zinc batteries, how to design a eutectic system adapted to alkaline electrolytes to achieve synergistic effects of antifreeze, ion conduction, and electrode protection, while also considering the availability of raw materials and the feasibility of industrial mass production, has become a pressing technical challenge. To address this, this application proposes a eutectic electrolyte for improving the low-temperature performance of nickel-zinc batteries. Summary of the Invention

[0005] To address the aforementioned problems, this invention provides a eutectic electrolyte for improving the low-temperature performance of nickel-zinc batteries. This electrolyte, by constructing a ternary composite eutectic system, achieves synergistic optimization of freeze resistance, ion conductivity, and electrode protection, significantly improving the charge-discharge efficiency and cycle stability of nickel-zinc batteries in low-temperature environments.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: This invention provides a eutectic electrolyte for improving the low-temperature performance of nickel-zinc batteries, comprising a basic alkaline electrolyte and a eutectic electrolyte additive.

[0007] The basic alkaline electrolyte is a potassium hydroxide (KOH) aqueous solution with a concentration of 6~8 mol / L; The mass of the eutectic electrolyte additive is 1% to 5% of the mass of the basic alkaline electrolyte; The eutectic electrolyte additive consists of a hydrogen bond donor, a hydrogen bond acceptor, and a functional modifier, with a molar ratio of (2~4):(1~2):(0.1~0.5).

[0008] The eutectic electrolyte forms a multi-level cross-linked hydrogen bond network in an alkaline system, thereby achieving synergistic optimization of the electrolyte's antifreeze properties, ion conductivity, and zinc anode protection.

[0009] The hydrogen bond donor is a sulfonamide compound, the hydrogen bond acceptor is an amphoteric surfactant, and the functional modifier is a metal ion complexing agent and / or a corrosion inhibitor.

[0010] As a preferred embodiment, the hydrogen bond donor may be selected from one or more of methanesulfonamide (MSA), trifluoromethanesulfonamide (TFMSA), and trimethylsulfonamide (TMSA).

[0011] Sulfonamides exhibit good chemical stability in alkaline environments. The NH bonds in their molecules can form hydrogen bonds with the OH⁻ in KOH aqueous solution, which helps to build a uniform hydrogen bond network and improve the stability of the electrolyte system.

[0012] Among them, methanesulfonamide has a high dielectric constant, which can promote the dissociation of ions in the electrolyte and improve ion migration ability; trifluoromethanesulfonamide contains a -CF3 group with a strong electron-withdrawing effect, which can effectively reduce the freezing point of the composite eutectic system; trimethylsulfonamide has both a high dielectric constant and hydrophobic modification properties, which is beneficial to optimize the hydrogen bond network structure and enhance the antifreeze performance of the system while improving ion conduction efficiency.

[0013] As a further preferred embodiment, the hydrogen bond donor may be a mixture of methanesulfonamide and trifluoromethanesulfonamide, a mixture of trifluoromethanesulfonamide and trimethylsulfonamide, or a mixture of methanesulfonamide and trimethylsulfonamide.

[0014] By combining different sulfonamide compounds, the nucleation and cross-linking effects of hydrogen bond networks can be further optimized, thereby improving the adaptability of the composite eutectic system to low-temperature environments.

[0015] As a preferred embodiment, the hydrogen bond acceptor is dodecyl dimethyl betaine (BS-12).

[0016] Dodecyl dimethyl betaine is an amphoteric surfactant that does not contain halide ions, thus avoiding corrosion of nickel-zinc battery electrodes. Its molecular structure contains carboxylate groups and quaternary ammonium cations, which can form an internal salt structure under alkaline conditions. This helps reduce the surface tension of the electrolyte, improves the wettability between the electrolyte and the electrode, and reduces interfacial contact resistance. Simultaneously, the long alkyl chain of dodecyl dimethyl betaine can form a dynamic adsorption layer on the zinc anode surface, inducing uniform zinc ion deposition and thereby inhibiting the growth of zinc dendrites.

[0017] As a preferred embodiment, the functional regulator may be selected from one or more of ethylenediaminetetraacetic acid tetrasodium (Na4EDTA) and sodium pyrophosphate (Na4P2O7).

[0018] The addition of functional regulators is to achieve multiple protections for the zinc anode and improve the electrolyte interface performance.

[0019] Among them, sodium ethylenediaminetetraacetate can form a stable complex with zinc ions, reduce the deposition rate of zinc ions, inhibit the growth of zinc dendrites and delay the passivation of zinc anode; sodium pyrophosphate can be adsorbed on the surface of zinc anode to form a dense protective film, inhibit the corrosion reaction of zinc anode and reduce the occurrence of hydrogen evolution side reaction.

[0020] As a further preferred embodiment, the functional modifier may be a mixture of sodium ethylenediaminetetraacetate and sodium pyrophosphate.

[0021] The combination of the two functional regulators can achieve the dual effects of complexation inhibition and adsorption protection, further improving the cycle stability of the zinc anode.

[0022] As a preferred embodiment, the molar ratio of the hydrogen bond donor, hydrogen bond acceptor, and functional modifier is (2.5~3.5):(1.2~1.8):(0.2~0.4).

[0023] Within this molar ratio range, the ternary composite eutectic system can form a relatively stable multi-level cross-linked hydrogen bond network structure, resulting in better synergistic effects in antifreeze properties, ion conductivity, and electrode protection.

[0024] As a preferred embodiment, the mass of the eutectic electrolyte additive is 2% to 4% of the mass of the base alkaline electrolyte.

[0025] As a preferred embodiment, the basic alkaline electrolyte is an aqueous solution of potassium hydroxide (KOH) with a concentration of 6.5~7.5 mol / L.

[0026] This invention also provides a method for preparing the above-mentioned eutectic electrolyte for improving the low-temperature performance of nickel-zinc batteries, comprising the following steps: S1. Mix the hydrogen bond donor, hydrogen bond acceptor and functional modifier according to the molar ratio, and stir evenly at a temperature of 15~35℃ to obtain a eutectic electrolyte additive. S2. Add the eutectic electrolyte additive obtained in step S1 to the basic alkaline electrolyte according to the mass ratio, and stir evenly to obtain the eutectic electrolyte.

[0027] The present invention also provides a nickel-zinc battery, comprising a positive electrode, a negative electrode, and the aforementioned eutectic electrolyte for improving the low-temperature performance of the nickel-zinc battery.

[0028] The present invention also provides the application of the above-mentioned eutectic electrolyte or the above-mentioned nickel-zinc battery in low-temperature environments, the applications including nickel-zinc battery energy storage, emergency power supply and / or low-temperature special equipment.

[0029] As a preferred embodiment, the low-temperature environment is -40°C to 0°C. The electrolyte of this application does not have its performance negatively affected at normal temperatures of 0°C to 25°C.

[0030] The core innovation of this invention lies in the construction of a ternary composite eutectic system of hydrogen bond donor-hydrogen bond acceptor-functional regulator. This system forms a multi-level cross-linked hydrogen bond network structure in a 6-8 mol / L KOH alkaline electrolyte, and its mechanism of action is as follows: (1) The NH bond in the hydrogen bond donor (methanesulfonamide, trifluoromethylsulfonamide or trimethylsulfonamide) molecule forms an intramolecular hydrogen bond with the OH⁻ in the system. At the same time, the hydrogen bond donor molecules are connected to each other through NH…O=S hydrogen bonds to form a eutectic core structure. (2) The carboxyl group (-COO⁻) in the hydrogen bond acceptor (dodecyl dimethyl betaine) forms NH…OC hydrogen bonds with the NH bonds of the eutectic core. Its quaternary ammonium cation (-N⁺(CH3)2-) interacts with the OH⁻ and sulfonamide groups in the system through electrostatic interaction, crosslinking the dispersed eutectic core to form a two-dimensional sheet-like hydrogen bond structure. (3) The oxygen-containing anion (EDTA) in the functional regulator (sodium ethylenediaminetetraacetate or sodium pyrophosphate) 4 ⁻ or P2O7 4 (⁻) It forms OH…O hydrogen bonds with hydrogen atoms in the two-dimensional hydrogen bond structure, and at the same time combines with Zn²⁺ in the system through complexation, anchoring Zn²⁺ in the hydrogen bond network, thereby forming a multi-level cross-linked three-dimensional hydrogen bond network structure.

[0031] The three-dimensional hydrogen bond network structure has the following functions: reducing intermolecular forces in the electrolyte, thus significantly lowering the electrolyte freezing point; providing continuous hydrogen bond channels for ion migration, thereby improving ionic conductivity under low temperature conditions; regulating the transport and deposition behavior of Zn²⁺, and inhibiting the formation and growth of zinc dendrites; enhancing the structural stability of the electrolyte system, slowing down the decomposition of components in alkaline environments, and achieving synergistic optimization of antifreeze properties, ion conductivity, and electrode protection.

[0032] Compared with the prior art, the present invention, which adopts the above technical solution, has the following beneficial effects: (1) This application constructs a ternary composite eutectic system of hydrogen bond donor-hydrogen bond acceptor-functional regulator, breaking through the limitations of traditional single or binary additives. Through a multi-level cross-linked hydrogen bond network, it achieves synergistic optimization of antifreeze properties, ion conductivity, and zinc anode protection. This system significantly reduces the freezing point of the electrolyte to below -40℃, while providing continuous ion channels at low temperatures, resulting in an ion conductivity of ≥10mS / cm at -40℃, effectively solving the problems of "contradiction between antifreeze and conductivity" and "insufficient electrode protection".

[0033] (2) The additives in this application have both high dielectric constant and strong antifreeze properties. They are halogen-free and do not corrode the electrode. They stabilize the zinc anode through a dual mechanism of complexation inhibition and adsorption protection. Each component has excellent chemical stability in the 6~8 mol / L KOH system and synergistically enhances the low-temperature performance.

[0034] (3) The molar ratio of the ternary system optimized in this application is (2~4):(1~2):(0.1~0.5), with the additive mass ratio being 1%~5%, suitable for alkaline electrolytes. Within the specific numerical ratio range of this application, the eutectic structure can be kept stable and the synergistic effect maximized. When deviating from this range, the freezing point of the battery increases, the conductivity decreases, and the zinc anode protection fails.

[0035] (4) None of the components in this application contain halide ions, thus avoiding the risk of electrode corrosion from the source. Each component exhibits excellent chemical stability in the highly alkaline KOH system, does not decompose during long-term use, has a wide electrochemical window, and is well compatible with nickel-zinc battery systems.

[0036] (5) The preparation process of this application is simple and can be completed by stirring at room temperature and pressure. The raw materials are all commercially available conventional products, which are inexpensive and easy to mass-produce. This electrolyte is suitable for various nickel-zinc batteries, and has broad application prospects, especially in the fields of low-temperature energy storage and emergency power supply. Detailed Implementation

[0037] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0038] The present invention will be further described in detail below with reference to specific embodiments, but the scope of protection of the present invention is not limited to the following embodiments.

[0039] In the following examples and comparative examples, all raw materials used were commercially available conventional products: methylsulfonamide (MSA) purity ≥99%, trifluoromethylsulfonamide (TFMSA) purity ≥99%, trimethylsulfonamide (TMSA) purity ≥98%, dodecyl dimethyl betaine (BS-12) purity ≥98%, tetrasodium ethylenediaminetetraacetate (Na4EDTA) purity ≥99%, sodium pyrophosphate (Na4P2O7) purity ≥98%, KOH purity ≥85%, and deionized water was standard laboratory deionized water. The eutectic electrolyte additive of this application is a composite eutectic system, composed of hydrogen bond donors, hydrogen bond acceptors, and functional modifiers in a specific molar ratio.

[0040] In the following examples and comparative examples, the performance testing methods are as follows: Freezing point test: Use a temperature-controlled cold bath to gradually lower the temperature, observe whether the electrolyte solidifies, and record the freezing point.

[0041] Ionic conductivity test: The ionic conductivity of the electrolyte was tested at different temperatures using an electrochemical workstation.

[0042] Battery cycle performance test: Nickel-zinc batteries with added eutectic electrolyte additives were cycled at -40℃ with a charge-discharge rate of 0.5C, and the capacity retention rate after 500 cycles was recorded.

[0043] Zinc negative electrode corrosion test: The weight loss method was used. The zinc electrode was immersed in an electrolyte containing additives and placed at -40℃ for 72 hours. The corrosion rate was then calculated.

[0044] Electrochemical stability test (linear sweep voltammetry, LSV): A three-electrode electrochemical workstation was used: glassy carbon working electrode (Φ3mm), platinum counter electrode (1cm×1cm), and Hg / HgO alkaline reference electrode; the glassy carbon electrode was polished sequentially with 0.3μm and 0.05μm alumina powder, ultrasonically cleaned with deionized water, and dried with nitrogen for later use; the scan rate was 50mV / s, the scan potential was -1.5~1.0V (vs Hg / HgO), and the test was conducted statically at 25℃ without stirring; the judgment criteria were: within the working potential range of the nickel-zinc battery (-1.2~0.6V vs Hg / HgO), the LSV curve showed no obvious oxidation / reduction peaks, only a stable double-layer capacitance current, and the current fluctuation amplitude was ≤5μA, which was considered as passing the electrochemical stability test.

[0045] Example 1: The molar composition of the composite eutectic system is: hydrogen bond donor: hydrogen bond acceptor: functional modifier = 2:1:0.1.

[0046] The hydrogen bond donor is MSA, the hydrogen bond acceptor is BS-12, and the functional modulator is Na4EDTA.

[0047] Preparation method: MSA, BS-12, and Na4EDTA were added sequentially to a beaker according to the above molar ratio. The mixture was stirred at 25°C and a stirring rate of 300 r / min for 30 min until completely dissolved to obtain a eutectic electrolyte additive. The above eutectic electrolyte additive was added at a mass fraction of 1% to a 6 mol / L KOH aqueous solution and stirred until homogeneous to obtain a nickel-zinc battery electrolyte.

[0048] Performance test results: The electrolyte has a freezing point of -42℃ and an ionic conductivity of 10.5 mS / cm at -40℃. The nickel-zinc battery using this electrolyte maintained 85.2% capacity after 500 cycles at -40℃ and 0.5C charge / discharge conditions. The zinc electrode corrosion rate was 0.02 mg / (cm²·h). In the LSV test, no oxidation / reduction peaks were observed in the -1.2~0.6V range, and the current fluctuation was 3.2 μA, indicating satisfactory electrochemical stability.

[0049] Example 2: The molar composition of the composite eutectic system is: hydrogen bond donor: hydrogen bond acceptor: functional modifier = 3:1.5:0.3.

[0050] The hydrogen bond donor is TFMSA, the hydrogen bond acceptor is BS-12, and the functional modulator is Na4EDTA.

[0051] Preparation method: TFMSA, BS-12, and Na4EDTA were added sequentially to a beaker according to the above molar ratio. The mixture was stirred at 25°C and a stirring rate of 300 r / min for 40 min until completely dissolved, yielding a eutectic electrolyte additive. This eutectic electrolyte additive was then added at a mass fraction of 3% to a 7 mol / L KOH aqueous solution and stirred until homogeneous, yielding a nickel-zinc battery electrolyte.

[0052] Performance test results: The electrolyte has a freezing point of -48℃ and an ionic conductivity of 12.3 mS / cm at -40℃. The nickel-zinc battery using this electrolyte retained 88.7% of its capacity after 500 cycles at -40℃ and 0.5C charge / discharge conditions. The zinc electrode corrosion rate was 0.015 mg / (cm²·h). In the LSV test, no oxidation / reduction peaks were observed in the -1.2~0.6V range, and the current fluctuation was 3.0 μA, indicating satisfactory electrochemical stability.

[0053] Example 3: The molar composition of the composite eutectic system is: hydrogen bond donor: hydrogen bond acceptor: functional modifier = 4:2:0.5.

[0054] The hydrogen bond donor is MSA, the hydrogen bond acceptor is BS-12, and the functional modulator is Na4P2O7.

[0055] Preparation method: MSA, BS-12, and Na4P2O7 were added sequentially to a beaker according to the above molar ratio. The mixture was stirred at 25°C and a stirring rate of 300 r / min for 50 min until completely dissolved to obtain a eutectic electrolyte additive. The above eutectic electrolyte additive was added at a mass fraction of 5% to an 8 mol / L KOH aqueous solution and stirred until homogeneous to obtain a nickel-zinc battery electrolyte.

[0056] Performance test results: The electrolyte has a freezing point of -52℃ and an ionic conductivity of 11.8 mS / cm at -40℃. The nickel-zinc battery using this electrolyte retained 87.3% of its capacity after 500 cycles at -40℃ and 0.5C charge / discharge conditions. The zinc electrode corrosion rate was 0.012 mg / (cm²·h). In the LSV test, no oxidation / reduction peaks were observed in the -1.2~0.6V range, and the current fluctuation was 3.8 μA, indicating satisfactory electrochemical stability.

[0057] Example 4: The molar composition of the composite eutectic system is: hydrogen bond donor: hydrogen bond acceptor: functional modifier = 3.5:1.8:0.4.

[0058] The hydrogen bond donor is TMSA, the hydrogen bond acceptor is BS-12, and the functional modulator is Na4P2O7.

[0059] Preparation method: TMSA, BS-12, and Na4P2O7 were added sequentially to a beaker according to the above molar ratio. The mixture was stirred at 25°C and a stirring rate of 300 r / min for 45 min until completely dissolved, yielding a eutectic electrolyte additive. This eutectic electrolyte additive was then added at a mass fraction of 4% to a 7.5 mol / L KOH aqueous solution and stirred until homogeneous, yielding a nickel-zinc battery electrolyte.

[0060] Performance test results: The electrolyte has a freezing point of -53℃ and an ionic conductivity of 12.1 mS / cm at -40℃. The nickel-zinc battery using this electrolyte retained 89.5% of its capacity after 500 cycles at -40℃ and 0.5C charge-discharge conditions. The zinc electrode corrosion rate was 0.011 mg / (cm²·h). In the LSV test, no oxidation / reduction peaks were observed in the -1.2~0.6V range, and the current fluctuation was 3.2 μA, indicating satisfactory electrochemical stability.

[0061] Example 5: The molar composition of the composite eutectic system is: hydrogen bond donor: hydrogen bond acceptor: functional modifier = 2.5:1.2:0.2.

[0062] The hydrogen bond donor is TMSA, the hydrogen bond acceptor is BS-12, and the functional modulator is Na4EDTA.

[0063] Preparation method: TMSA, BS-12, and Na4EDTA were added sequentially to a beaker according to the above molar ratio. The mixture was stirred at 25°C and a stirring rate of 300 r / min for 35 min until completely dissolved, yielding a eutectic electrolyte additive. The above eutectic electrolyte additive was added at a mass fraction of 2% to a 6.5 mol / L KOH aqueous solution and stirred until homogeneous, yielding a nickel-zinc battery electrolyte.

[0064] Performance test results: The electrolyte has a freezing point of -46℃ and an ionic conductivity of 11.2 mS / cm at -40℃. The nickel-zinc battery using this electrolyte retained 86.8% of its capacity after 500 cycles at -40℃ and 0.5C charge / discharge conditions. The zinc electrode corrosion rate was 0.018 mg / (cm²·h). In the LSV test, no oxidation / reduction peaks were observed in the -1.2~0.6V range, and the current fluctuation was 3.5 μA, indicating satisfactory electrochemical stability.

[0065] Example 6: The molar composition of the composite eutectic system is: hydrogen bond donor: hydrogen bond acceptor: functional modifier = 3:1.6:0.35.

[0066] The hydrogen bond donor is TFMSA, the hydrogen bond acceptor is BS-12, and the functional modulator is Na4P2O7.

[0067] Preparation method: TFMSA, BS-12, and Na4P2O7 were added sequentially to a beaker according to the above molar ratio. The mixture was stirred at 25°C and a stirring rate of 300 r / min for 42 min until completely dissolved, yielding a eutectic electrolyte additive. This eutectic electrolyte additive was then added at a mass fraction of 3.5% to a 7.2 mol / L KOH aqueous solution and stirred until homogeneous, yielding a nickel-zinc battery electrolyte.

[0068] Performance test results: The electrolyte has a freezing point of -50℃ and an ionic conductivity of 12.5 mS / cm at -40℃. The nickel-zinc battery using this electrolyte maintained 89.1% capacity after 500 cycles at -40℃ and 0.5C charge / discharge conditions. The zinc electrode corrosion rate was 0.010 mg / (cm²·h). In the LSV test, no oxidation / reduction peaks were observed in the -1.2~0.6V range, and the current fluctuation was 2.8 μA, indicating satisfactory electrochemical stability.

[0069] Example 7: The molar composition of the composite eutectic system is: hydrogen bond donor: hydrogen bond acceptor: functional modifier = 2.8:1.4:0.25.

[0070] The hydrogen bond donor is a mixture of MSA and TFMSA (molar ratio 1:1), the hydrogen bond acceptor is BS-12, and the functional modifier is Na4EDTA.

[0071] Preparation method: MSA and TFMSA were added to a beaker at a 1:1 molar ratio and stirred at 25°C and 300 r / min for 10 min to obtain a homogeneous hydrogen bond donor composite solution. BS-12 and Na4EDTA were added sequentially to the hydrogen bond donor composite solution at a molar ratio, and stirred at 25°C and 300 r / min for 28 min until all components were completely dissolved to obtain a composite eutectic additive. The composite eutectic additive was added to a 6.8 mol / L KOH aqueous solution at a mass fraction of 2.5% and stirred until homogeneous to obtain the eutectic electrolyte of the present invention.

[0072] Performance test results: Electrolyte freezing point -51℃, ionic conductivity 12.6 mS / cm at -40℃; capacity retention 90.2% after 500 cycles at -40℃ and 0.5C; zinc electrode corrosion rate 0.009 mg / (cm²·h). In LSV testing, no oxidation / reduction peaks were observed in the -1.2~0.6V range, current fluctuation was 3.1 μA, and electrochemical stability was satisfactory.

[0073] Example 8: The molar composition of the composite eutectic system is: hydrogen bond donor: hydrogen bond acceptor: functional modifier = 3.2:1.7:0.38.

[0074] The hydrogen bond donor is a mixture of TFMSA and TMSA (molar ratio 1:1), the hydrogen bond acceptor is BS-12, and the functional modifier is Na4P2O7.

[0075] Preparation method: TFMSA and TMSA were added to a beaker at a 1:1 molar ratio and stirred at 25°C and 300 r / min for 12 min until homogeneous to obtain a homogeneous hydrogen bond donor composite solution. BS-12 and Na4P2O7 were added sequentially to the above hydrogen bond donor composite solution at a molar ratio, and stirred at 25°C and 300 r / min for 31 min until all components were completely dissolved to obtain a composite eutectic additive. The composite eutectic additive was added to a 7.3 mol / L KOH aqueous solution at a mass fraction of 3.8% and stirred until homogeneous to obtain the eutectic electrolyte of the present invention.

[0076] Performance test results: Electrolyte freezing point -55℃, ionic conductivity 12.8 mS / cm at -40℃; capacity retention 91.5% after 500 cycles at -40℃ and 0.5C; zinc electrode corrosion rate 0.008 mg / (cm²·h). In LSV testing, no oxidation / reduction peaks were observed in the -1.2~0.6V range, current fluctuation was 2.9 μA, and electrochemical stability was satisfactory.

[0077] Example 9: The molar composition of the composite eutectic system is: hydrogen bond donor: hydrogen bond acceptor: functional modifier = 3.6:1.9:0.42.

[0078] The hydrogen bond donor is a mixture of MSA and TMSA (molar ratio 1:2), the hydrogen bond acceptor is BS-12, and the functional modifier is Na4P2O7.

[0079] Preparation method: MSA and TMSA were added to a beaker at a molar ratio of 1:2 and stirred at 25°C and 300 r / min for 15 min until homogeneous to obtain a homogeneous hydrogen bond donor composite solution; BS-12 and Na4P2O7 were added sequentially to the above hydrogen bond donor composite solution at a molar ratio, and stirred at 25°C and 300 r / min for 31 min until all components were completely dissolved to obtain a composite eutectic additive; the composite eutectic additive was added to a 7.6 mol / L KOH aqueous solution at a mass fraction of 4.2% and stirred until homogeneous to obtain the eutectic electrolyte of the present invention.

[0080] Performance test results: Electrolyte freezing point -54℃, ionic conductivity 12.7 mS / cm at -40℃; capacity retention 90.8% after 500 cycles at -40℃ and 0.5C; zinc electrode corrosion rate 0.0085 mg / (cm²·h). In LSV testing, no oxidation / reduction peaks were observed in the -1.2~0.6V range, current fluctuation was 3.3 μA, and electrochemical stability was satisfactory.

[0081] Example 10: The molar composition of the composite eutectic system is: hydrogen bond donor: hydrogen bond acceptor: functional modifier = 2.2:1.1:0.15.

[0082] The hydrogen bond donor is MSA, the hydrogen bond acceptor is BS-12, and the functional modifier is a mixture of Na4EDTA and Na4P2O7 (molar ratio 2:1).

[0083] Preparation method: MSA is used as a hydrogen bond donor, without the need for compounding, and is directly used as a homogeneous hydrogen bond donor composite solution for later use; BS-12 and Na4EDTA+Na4P2O7 functional regulator premixed at a molar ratio are added sequentially to the above hydrogen bond donor composite solution, and stirred at 25℃ and 300r / min for 32min until all components are completely dissolved to obtain a composite eutectic additive; the composite eutectic additive is added to a 6.2mol / L KOH aqueous solution at a mass fraction of 1.5% and stirred evenly to obtain the eutectic electrolyte of the present invention.

[0084] Performance test results: Electrolyte freezing point -45℃, ionic conductivity 11.5 mS / cm at -40℃; capacity retention 87.9% after 500 cycles at -40℃ and 0.5C; zinc electrode corrosion rate 0.013 mg / (cm²·h). LSV testing showed no oxidation / reduction peaks in the -1.2~0.6V range, current fluctuation range 4.0 μA, indicating satisfactory electrochemical stability.

[0085] Example 11: The molar composition of the composite eutectic system is: hydrogen bond donor: hydrogen bond acceptor: functional modifier = 2.9:1.5:0.3.

[0086] The hydrogen bond donor is TFMSA, the hydrogen bond acceptor is BS-12, and the functional modifier is a mixture of Na4EDTA and Na4P2O7 (molar ratio 1:1).

[0087] Preparation method: TFMSA is used as a hydrogen bond donor, without the need for compounding, and is directly used as a homogeneous hydrogen bond donor composite solution for later use; BS-12 and Na4EDTA+Na4P2O7 functional regulator premixed at a 1:1 molar ratio are added sequentially to the above hydrogen bond donor composite solution, and the mixture is stirred at 25℃ and 300r / min for 40min until all components are completely dissolved to obtain a composite eutectic additive; 3% by mass of the composite eutectic additive is added to a 7.0mol / L KOH aqueous solution and stirred evenly to obtain the eutectic electrolyte of the present invention.

[0088] Performance test results: Electrolyte freezing point -52℃, ionic conductivity 12.9 mS / cm at -40℃; capacity retention 91.2% after 500 cycles at -40℃ and 0.5C; zinc electrode corrosion rate 0.0075 mg / (cm²·h). LSV testing showed no oxidation / reduction peaks in the -1.2~0.6V range, current fluctuation range 2.7 μA, indicating satisfactory electrochemical stability.

[0089] Comparative Example 1: Without adding the compound eutectic electrolyte additive of this application, only a 7mol / L KOH aqueous solution was used as the nickel-zinc battery electrolyte, and the other conditions were the same as in Example 2.

[0090] Performance test results: The electrolyte has a freezing point of -12℃ and completely solidifies at -40℃, making it impossible to test the ionic conductivity; the nickel-zinc battery using this electrolyte cannot be charged and discharged normally at -40℃, and the cycle performance cannot be tested; the zinc electrode corrosion rate is 0.15 mg / (cm²·h).

[0091] Comparative Example 2: Instead of using a compound formulation, only MSA was added as an electrolyte additive at a concentration of 3% (same as in Example 2), with all other conditions remaining the same as in Example 2.

[0092] Performance test results: The electrolyte has a freezing point of -30℃ and an ionic conductivity of 7.8 mS / cm at -40℃; the nickel-zinc battery using this electrolyte retains 70.9% of its capacity after 500 cycles at -40℃ and 0.5C charge-discharge conditions; the zinc electrode corrosion rate is 0.072 mg / (cm²·h), indicating poor corrosion inhibition and significant zinc dendrite growth.

[0093] Comparative Example 3: Instead of using a compound formulation, only Na4P2O7 was added as an electrolyte additive at a concentration of 5% (consistent with Example 3), with all other conditions remaining the same as in Example 3.

[0094] Performance test results: The electrolyte has a freezing point of -18℃ and partially solidifies at -40℃, with an ionic conductivity of only 5.5 mS / cm. The nickel-zinc battery using this electrolyte retains 70.3% of its capacity after 500 cycles at -40℃ and 0.5C charge-discharge conditions. The zinc electrode corrosion rate is 0.063 mg / (cm²·h). Although it can suppress zinc dendrites to some extent, it cannot solve the problem of low-temperature solidification, resulting in extremely poor low-temperature performance of the battery.

[0095] Comparative Example 4: The compound of TFMSA, BS-12 and Na4EDTA was used, but the compound ratio deviated from the range specified in this application. The molar ratio was 1:3:1, which exceeded the range of (2~4):(1~2):(0.1~0.5). The amount added was 3% (consistent with Example 2), and the other conditions were the same as in Example 2.

[0096] Performance test results: The freezing point of this electrolyte is -36℃, and the ionic conductivity at -40℃ is 8.6mS / cm; the nickel-zinc battery using this electrolyte retains 75.4% of its capacity after 500 cycles under -40℃ and 0.5C charge-discharge conditions; the zinc electrode corrosion rate is 0.051mg / (cm²·h), indicating that the synergistic effect of the compounding has failed, and the low-temperature performance and cycle stability have decreased significantly.

[0097] Comparative Example 5: The mixture of MSA, BS-12, and Na4EDTA was used, with the same ratio as in Example 1 (2:1:0.1), but the amount added was 0.8% (lower than the 1%~5% range specified in this invention), and the other conditions were the same as in Example 1.

[0098] Performance test results: The electrolyte has a freezing point of -33℃ and an ionic conductivity of 8.2 mS / cm at -40℃; the nickel-zinc battery using this electrolyte retains 77.0% of its capacity after 500 cycles under -40℃ and 0.5C charge-discharge conditions; the zinc electrode corrosion rate is 0.059 mg / (cm²·h), indicating insufficient content of compound additives and inability to fully exert their synergistic effect.

[0099] Comparative Example 6: The mixture of MSA, BS-12, and NaCl was used, wherein the functional modifier NaCl is not Na4EDTA or Na4P2O7 as defined in this application. The mixing ratio was 3:1.5:0.3 (consistent with Example 2), the addition amount was 3%, and the other conditions were consistent with Example 2.

[0100] Performance test results: The electrolyte has a freezing point of -38℃ and an ionic conductivity of 8.9 mS / cm at -40℃. The nickel-zinc battery using this electrolyte maintained a capacity retention of 74.5% after 500 cycles at -40℃ and 0.5C charge / discharge conditions. The zinc electrode corrosion rate was 0.065 mg / (cm²·h). NaCl could not effectively protect the zinc anode, and the introduction of Cl⁻ corroded the electrode, resulting in extremely poor battery stability. A significant reduction peak appeared in the -0.8~0.0V range during LSV testing, with a current fluctuation of 12.3 μA.

[0101] The above Examples 1-11 and Comparative Examples 1-6 were used to systematically test the freezing point, -40℃ ionic conductivity, low-temperature cycling performance of nickel-zinc batteries equipped with the electrolyte, and zinc anode corrosion rate of each system. The test results are summarized in Table 1 below.

[0102] Table 1: Comparison of performance test results between each embodiment and the comparative example Example 1 -42 10.5 85.2 0.020 Example 2 -48 12.3 88.7 0.015 Example 3 -52 11.8 87.3 0.012 Example 4 -53 12.1 89.5 0.011 Example 5 -46 11.2 86.8 0.018 Example 6 -50 12.5 89.1 0.010 Example 7 -51 12.6 90.2 0.009 Example 8 -55 12.8 91.5 0.008 Example 9 -54 12.7 90.8 0.0085 Example 10 -45 11.5 87.9 0.013 Example 11 -52 12.9 91.2 0.0075 Comparative Example 1 -12 Unable to test Unable to test 0.150 Comparative Example 2 -30 7.8 70.9 0.072 Comparative Example 3 -18 5.5 70.3 0.063 Comparative Example 4 -36 8.6 75.4 0.051 Comparative Example 5 -33 8.2 77.0 0.059 Comparative Example 6 -38 8.9 74.5 0.065 Performance test results analysis The technical effects of this application will be further explained below with reference to the performance test data of Examples 1 to 11 and Comparative Examples 1 to 6 listed in Table 1.

[0103] 1. The influence of composite eutectic system on the basic low-temperature properties of electrolyte As shown in Table 1, Comparative Example 1, using a 7 mol / L KOH aqueous solution as the electrolyte without any additives, had a freezing point of -12°C and completely solidified at -40°C, lacking ion conductivity and thus the battery could not be charged and discharged at low temperatures. In contrast, the electrolytes prepared in Examples 1-11 all had freezing points below -40°C, with the lowest reaching -55°C (Example 8), and their ionic conductivity at -40°C was not lower than 10 mS / cm. These data indicate that the ternary composite eutectic system of this application, by constructing a multi-level cross-linked hydrogen bond network, reduces the intermolecular forces between electrolyte components, providing continuous channels for ion migration while suppressing low-temperature solidification, thereby solving the problem of ion conductivity failure of alkaline electrolytes at low temperatures.

[0104] Comparative Example 2 used MSA as a single additive, and Comparative Example 3 used Na4P2O7 as a single additive. Their electrolyte freezing points were -30℃ and -18℃, respectively, both significantly higher than those of the embodiments in this application. At -40℃, their ionic conductivity was 7.8 mS / cm and 5.5 mS / cm, respectively, showing a significant decrease in ion migration efficiency. This indicates that a single additive can only achieve a single function and is insufficient to construct a stable multi-level cross-linked hydrogen bond network, failing to simultaneously lower the freezing point and maintain low-temperature ion conduction capability. The above comparison verifies the necessity of the ternary complex synergistic design of hydrogen bond donor-hydrogen bond acceptor-functional modifier in this application.

[0105] Examples 7-9 used a combination of two sulfonamide compounds as hydrogen bond donors, while Examples 10-11 used a combination of Na4EDTA and Na4P2O7 as functional modifiers. The solidification point of the electrolyte was further reduced compared to the examples using a single component, and the low-temperature ionic conductivity was simultaneously improved. These results indicate that the combination of different hydrogen bond donors is beneficial for optimizing the nucleation and cross-linking of the hydrogen bond network, and the combination of different functional modifiers can enhance the hydrogen bond network modification effect while achieving zinc anode protection, thereby improving the adaptability of the composite eutectic system in low-temperature environments.

[0106] 2. The impact of core process parameters on electrolyte and battery performance This application specifies the molar ratio of components in the ternary composite eutectic system, the mass addition amount of additives in the alkaline electrolyte, and the concentration of KOH electrolyte. The rationality of each parameter range is analyzed below with reference to data from examples and comparative examples.

[0107] (1) Component molar ratio In Examples 1-11, the molar ratio of hydrogen bond donor, hydrogen bond acceptor, and functional regulator was within the range of (2-4):(1-2):(0.1-0.5), and both the electrolyte and battery performance were good. Comparative Example 4 adjusted the molar ratio to 1:3:1, exceeding the range specified in this application. Its electrolyte freezing point increased to -36℃, and the ionic conductivity decreased to 8.6 mS / cm at -40℃. The nickel-zinc battery equipped with this electrolyte retained 75.4% of its capacity after 500 cycles at -40℃ and 0.5C. Analysis showed that when the amount of hydrogen bond acceptor was too high, the electrolyte viscosity increased, disrupting the three-dimensional cross-linked structure of the hydrogen bond network; when the amount of functional regulator was too high, it may excessively complex with zinc ions, inhibiting the normal deposition and deintercalation of zinc ions, thus weakening the synergistic effect of the ternary system. The above data shows that the molar ratio range defined in this application is the preferred range for achieving the synergistic effect of antifreeze, ion conduction and electrode protection. Deviating from this range will lead to significant performance degradation.

[0108] (2) Amount of additives added In Examples 1-11, the mass of the eutectic electrolyte additive was 1%-5% of the mass of the alkaline electrolyte, and the performance indicators of each example met expectations. Comparative Example 5 reduced the addition amount to 0.8%, below the lower limit specified in this application. Its electrolyte freezing point rose to -33°C, and the ionic conductivity at -40°C dropped to 8.2 mS / cm. After 500 cycles at -40°C, the battery retained 77.0% of its capacity. When the addition amount is insufficient, it is difficult to form a complete multi-level cross-linked hydrogen bond network in the electrolyte, and the eutectic system cannot fully play its role in antifreeze, conductivity, and electrode protection. Excessive addition may lead to excessive electrolyte viscosity, which is detrimental to ion migration. Therefore, an addition amount range of 1%-5% is the preferred range for achieving a balance between low-temperature performance and ion conduction performance.

[0109] (3) KOH electrolyte concentration Examples 1-11 all use a KOH aqueous solution with a concentration of 6-8 mol / L as the basic alkaline electrolyte. This concentration range has good compatibility with the composite eutectic additive of this application, which is beneficial to improving the structural stability of the hydrogen bond network and the ionic conductivity of the electrolyte. If the concentration deviates from this range, when the KOH concentration is too low, the ionic strength of the electrolyte will be insufficient; when the KOH concentration is too high, the viscosity of the electrolyte will increase more sharply at low temperatures, both of which may weaken the synergistic effect of the composite eutectic system. In addition, this concentration range is consistent with the conventional alkaline electrolyte system of nickel-zinc batteries, and no adjustment is required to the existing battery production process, which has good industrial adaptability.

[0110] 3. The influence of composite eutectic system on the stability of zinc anode and low-temperature cycle performance of battery Dendrite growth, passivation, corrosion, and hydrogen evolution side reactions of the zinc anode at low temperatures are significant factors limiting the cycle life of nickel-zinc batteries. This application achieves multiple protections for the zinc anode through the synergistic effect of hydrogen bond acceptors and functional regulators, thereby improving the cycle stability of the battery and the corrosion resistance of the zinc anode in low-temperature environments.

[0111] (1) Corrosion resistance of zinc anode In Comparative Example 1, the zinc electrode corrosion rate of the pure KOH electrolyte was 0.15 mg / (cm²·h), with severe oxide layer and corrosion pits appearing on the electrode surface, and significant hydrogen evolution side reaction. In the single-additive systems of Comparative Examples 2 and 3, the zinc electrode corrosion rates were 0.072 mg / (cm²·h) and 0.063 mg / (cm²·h), respectively, which, although lower than Comparative Example 1, were still at a relatively high level. In contrast, the zinc electrode corrosion rates in Examples 1-11 were all no higher than 0.02 mg / (cm²·h), with the lowest being 0.0075 mg / (cm²·h) (Example 11). The reason for this is that: the hydrogen bond acceptor BS-12 forms a dynamic adsorption layer on the zinc anode surface, guiding the uniform deposition of zinc ions; the functional regulator Na4EDTA forms a stable complex with zinc ions, inhibiting dendrite growth and passivation; and the functional regulator Na4P2O7 forms a dense protective film on the zinc anode surface, blocking contact with corrosive media. The synergistic effect of the three components effectively inhibited zinc anode corrosion and hydrogen evolution side reactions.

[0112] (2) Low-temperature cycle performance of the battery The nickel-zinc battery in Comparative Example 1 could not be charged and discharged normally at -40°C. After 500 cycles at -40°C and 0.5C, the capacity retention of batteries in Comparative Examples 2-6 did not exceed 77.0%. However, the batteries in Examples 1-11, under the same test conditions, maintained a capacity retention of no less than 85% after 500 cycles, with the highest being 91.5% (Example 8). These data indicate that the composite eutectic system of this application not only improves the low-temperature solidification and ion migration problems of the electrolyte but also effectively inhibits dendrite growth, passivation, and corrosion reactions of the zinc anode, reducing the loss of active material and thus ensuring the long-term cycle stability of the nickel-zinc battery in low-temperature environments. Furthermore, the low-temperature cycle performance of the multi-component composite system in Examples 7-11 is superior to that of the single-component examples, further demonstrating that multi-component composites can enhance the protection effect on the zinc anode.

[0113] (3) Compatibility of halogen-free additives Comparative Example 6 used NaCl as a functional modifier, introducing halide ions (Cl⁻), which led to additional corrosion of the zinc electrode. After 500 cycles at -40°C, the battery retained 74.5% of its capacity, with a corrosion rate of 0.065 mg / (cm²·h). In contrast, the hydrogen bond donor, hydrogen bond acceptor, and functional modifier selected in this application are all halide-free, avoiding the risk of halide ion corrosion to the electrode through component design. This also improves the compatibility of the composite eutectic system with the nickel cathode and zinc anode, thus extending the battery's lifespan.

[0114] This application presents a ternary composite eutectic electrolyte additive that utilizes a hydrogen bond donor, hydrogen bond acceptor, and functional regulator. Through precise component screening, molar ratio optimization, and multi-level cross-linked hydrogen bond network design, it successfully overcomes the core pain points of existing nickel-zinc battery electrolytes: the contradiction between antifreeze properties and ionic conductivity, and insufficient zinc anode protection. It achieves synergistic optimization of electrolyte antifreeze properties, ionic conductivity, and zinc anode protection, yielding significant technical benefits. In summary, this ternary composite eutectic electrolyte additive effectively solves the industry problem of low-temperature performance degradation in nickel-zinc batteries, significantly improving their performance in low-temperature environments. This promotes the widespread application of nickel-zinc batteries in cold regions and low-temperature special equipment, demonstrating significant industrial application value.

[0115] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

[0116] This article uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only for the purpose of helping to understand the method and core ideas of the present invention. The above descriptions are only preferred embodiments of the present invention. It should be noted that due to the limitations of textual expression, while there are objectively infinite specific structures, those skilled in the art can make several improvements, modifications, or changes without departing from the principles of the present invention, and can also combine the above technical features in an appropriate manner. These improvements, modifications, changes, or combinations, or the direct application of the inventive concept and technical solution to other situations without modification, should all be considered within the scope of protection of the present invention.

Claims

1. A eutectic electrolyte for improving low-temperature performance of a nickel-zinc battery, characterized in that, Includes basic alkaline electrolyte and eutectic electrolyte additives; The basic alkaline electrolyte is a potassium hydroxide aqueous solution with a concentration of 6-8 mol / L; The mass of the eutectic electrolyte additive is 1% to 5% of the mass of the basic alkaline electrolyte; The eutectic electrolyte additive consists of a hydrogen bond donor, a hydrogen bond acceptor, and a functional modifier, with a molar ratio of (2~4):(1~2):(0.1~0.5). The hydrogen bond donor is a sulfonamide compound, the hydrogen bond acceptor is an amphoteric surfactant, and the functional modifier is a metal ion complexing agent and / or a corrosion inhibitor.

2. The eutectic electrolyte according to claim 1, characterized in that, The hydrogen bond donor is selected from one or more of methanesulfonamide, trifluoromethanesulfonamide, and trimethylsulfonamide.

3. The eutectic electrolyte according to claim 2, characterized in that, The hydrogen bond donor is a mixture of methanesulfonamide and trifluoromethanesulfonamide, or a mixture of trifluoromethanesulfonamide and trimethylsulfonamide, or a mixture of methanesulfonamide and trimethylsulfonamide.

4. The eutectic electrolyte according to claim 1, characterized in that, The hydrogen bond acceptor is dodecyl dimethyl betaine.

5. The eutectic electrolyte according to claim 1, characterized in that, The functional regulator is selected from one or more of ethylenediaminetetraacetic acid tetrasodium and sodium pyrophosphate.

6. The eutectic electrolyte according to claim 5, characterized in that, The functional modifier is a mixture of ethylenediaminetetraacetic acid tetrasodium and sodium pyrophosphate.

7. The eutectic electrolyte according to claim 1, characterized in that, The molar ratio of the hydrogen bond donor, hydrogen bond acceptor, and functional modulator is (2.5~3.5):(1.2~1.8):(0.2~0.4).

8. The eutectic electrolyte according to claim 1, characterized in that, The mass of the eutectic electrolyte additive is 2% to 4% of the mass of the basic alkaline electrolyte.

9. The eutectic electrolyte according to claim 1, characterized in that, The basic alkaline electrolyte is a 6.5~7.5 mol / L potassium hydroxide aqueous solution.

10. A method for preparing a eutectic electrolyte for improving the low-temperature performance of nickel-zinc batteries as described in any one of claims 1-9, characterized in that, Includes the following steps: S1. Mix the hydrogen bond donor, hydrogen bond acceptor and functional modifier according to the molar ratio, and stir evenly at 15-35°C to obtain a eutectic electrolyte additive. S2. Add the eutectic electrolyte additive obtained in step S1 to the basic alkaline electrolyte according to the mass ratio, and stir evenly to obtain the final product.

11. A nickel-zinc battery, comprising a positive electrode, a negative electrode, and an electrolyte, characterized in that, The electrolyte is the eutectic electrolyte for improving the low-temperature performance of nickel-zinc batteries as described in any one of claims 1-9.

12. The eutectic electrolyte as described in any one of claims 1-9, or the application of the nickel-zinc battery as described in claim 11 in a low-temperature environment, wherein the application includes nickel-zinc battery energy storage, emergency power supply and / or low-temperature special equipment.

13. The application according to claim 12, characterized in that, The low-temperature environment is from -40°C to 0°C.