Two-phase decoupling eutectic gel electrolyte, and preparation method therefor and use thereof

Abstract

A two-phase decoupling eutectic gel electrolyte, and a preparation method therefor and the use thereof. The two-phase decoupling eutectic gel electrolyte comprises an acidic eutectic gel electrolyte and an alkaline eutectic gel electrolyte, which are arranged in a stacked manner, wherein a dispersion medium of the acidic eutectic gel electrolyte at least comprises an acidic eutectic solvent and a first metal salt; and a dispersion medium of the alkaline eutectic gel electrolyte at least comprises an alkaline eutectic solvent and a second metal salt.

Description

Dual-phase decoupled eutectic gel electrolyte and its preparation method and application

[0001] Related applications

[0002] This application claims priority to Chinese patent application No. 202311518552.7, filed on November 14, 2023, entitled “Decoupled eutectic gel electrolyte, preparation method and application thereof”, the entire contents of which are incorporated by reference into this application. Technical Field

[0003] The present application relates to the technical field of decoupled electrolytes, and in particular to a two-phase decoupled eutectic gel electrolyte and a preparation method and application thereof. Background Art

[0004] In recent years, the use of decoupled electrolytes has been shown to overcome the voltage limitations of traditional aqueous zinc-based batteries and achieve high performance close to the theoretical specific capacity, thereby achieving high energy density. However, current decoupled batteries developed based on liquid decoupled electrolytes require expensive ion-selective membranes and have complex battery structures, making the production of soft-pack batteries impossible. Furthermore, the presence of ion-selective membranes significantly increases ion transport resistance, resulting in poor rate performance and the inability to achieve extremely fast charging, severely limiting their large-scale practical application.

[0005] While the use of decoupled hydrogel electrolytes can avoid expensive ion-selective membranes and simplify battery structure, the serious crossover between hydrogen and hydroxide ions at the interface of decoupled hydrogel electrolytes results in a short battery life, far from meeting the requirements of practical application. Furthermore, hydrogels are prone to freezing at low temperatures and losing water at high temperatures, hindering their practical application in extreme environments.

[0006] Summary of the Invention

[0007] According to various embodiments of the present application, a dual-phase decoupling eutectic gel electrolyte is provided, wherein the dual-phase decoupling eutectic gel electrolyte includes an acidic eutectic gel electrolyte and an alkaline eutectic gel electrolyte arranged in a stacked manner;

[0008] The dispersion medium of the acidic eutectic gel electrolyte comprises at least an acidic eutectic solvent and a first metal salt; the dispersion medium of the alkaline eutectic gel electrolyte comprises at least an alkaline eutectic solvent and a second metal salt.

[0009] The present application also provides a method for preparing a two-phase decoupled eutectic gel electrolyte, comprising the following steps:

[0010] respectively preparing a first precursor for preparing an acidic eutectic gel electrolyte and a second precursor for preparing an alkaline eutectic gel electrolyte;

[0011] The first precursor is prepared into an acidic eutectic gel electrolyte and the second precursor is prepared into an alkaline eutectic gel electrolyte, and then the acidic eutectic gel electrolyte and the alkaline eutectic gel electrolyte are laminated to obtain a dual-phase decoupled eutectic gel electrolyte;

[0012] Alternatively, either the first precursor or the second precursor is first prepared into a low-melting eutectic gel electrolyte, and then the other precursor is placed on the low-melting eutectic gel electrolyte to in situ prepare another low-melting eutectic gel electrolyte to obtain a two-phase decoupled low-melting eutectic gel electrolyte.

[0013] The present application also provides an application of the dual-phase decoupling eutectic gel electrolyte in a device.

[0014] The present application also provides a decoupling battery, which includes a positive electrode sheet, the two-phase decoupling eutectic gel electrolyte and a negative electrode sheet stacked in sequence, wherein the acidic low eutectic gel electrolyte in the two-phase decoupling low eutectic gel electrolyte is adhered to the positive electrode sheet, and the alkaline low eutectic gel electrolyte is adhered to the negative electrode sheet.

[0015] The present application also provides a soft-pack battery, the battery core of which includes at least one positive electrode sheet and at least one negative electrode sheet, the positive electrode sheets and the negative electrode sheets are alternately stacked in sequence, and the two-phase decoupling low-melting eutectic gel electrolyte is sandwiched between adjacent positive electrode sheets and negative electrode sheets, the acidic low-melting eutectic gel electrolyte in the two-phase decoupling low-melting eutectic gel electrolyte is adhered to the positive electrode sheet, and the alkaline low-melting eutectic gel electrolyte is adhered to the negative electrode sheet.

[0016] The present application sets the two-phase decoupling eutectic gel electrolyte as a double-layer structure, and uses an acidic low eutectic solvent and an alkaline low eutectic solvent as a dispersion medium respectively, so that the two-phase decoupling low eutectic gel electrolyte has excellent conductivity, high metal ion migration number, wide electrochemical window, wide temperature range tolerance, adhesion and tensile properties, and can effectively avoid the crossover of hydrogen ions and hydroxide ions and the crossover of active metal ions in the positive and negative electrode electrolytes. Therefore, when the two-phase decoupling low eutectic gel electrolyte of the present application is used for decoupling batteries, not only can the use of expensive ion selective membranes be avoided and the battery structure be simplified, but also the rate limit of traditional decoupling electrolytes can be broken through, so that the decoupling battery can achieve extremely fast charging under ultra-low temperature and high temperature conditions, and maintain high capacity, high energy density and long cycle stability, and has good application prospects in the field of large-scale energy storage in a wide temperature range.

[0017] In addition, the use of the dual-phase decoupled eutectic gel electrolyte of the present application can realize the assembly of soft-pack batteries with high capacity and high energy density, which have excellent comprehensive electrochemical performance and a wide operating temperature range, especially ultra-low temperature and extremely fast charging performance. At the same time, soft-pack batteries are inexpensive and have intrinsic safety. They can withstand bending, impact, puncture, shear damage, burning and water immersion, and also have good application prospects in the field of large-scale energy storage with a wide temperature range.

[0018] The details of one or more embodiments of the present application are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the present application will become apparent from the description, drawings, and claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to better describe and illustrate the embodiments and / or examples of the inventions disclosed herein, reference may be made to one or more of the accompanying drawings. The additional details or examples used to describe the accompanying drawings should not be considered to limit the scope of the disclosed inventions, the presently described embodiments and / or examples, and any of the best modes currently understood for these inventions.

[0020] FIG1 is a schematic structural diagram of the dual-phase decoupled eutectic gel electrolyte of the present application.

[0021] FIG2 is a schematic diagram of a partial structure of the decoupling battery of the present application.

[0022] FIG3 is a schematic structural diagram of the battery core of the soft-pack battery of the present application.

[0023] FIG4 is a tensile test diagram of the dual-phase decoupled eutectic gel electrolyte prepared in Example 4 of the present application.

[0024] FIG5 is a graph showing the adhesion performance of the dual-phase decoupled eutectic gel electrolyte prepared in Example 4 of the present application.

[0025] Figure 6 shows the conductivity and activation energy of the acid-base two-phase decoupled eutectic gel electrolyte prepared in Example 4 of the present application and the acid-base decoupled hydrogel electrolyte prepared in Comparative Example 1 of the present application at different temperatures.

[0026] Figure 7 shows the electrochemical windows of the acid-base two-phase decoupling eutectic gel electrolyte prepared in Example 4 of the present application and the acid-base decoupling hydrogel electrolyte prepared in Comparative Example 1 of the present application.

[0027] FIG8 shows the open circuit voltage of a full cell using the dual-phase decoupled eutectic gel electrolyte Zn||MnO2 prepared in Example 1.

[0028] FIG9 shows the discharge polarization curves of the full battery using the dual-phase decoupled eutectic gel electrolyte Zn||MnO2 prepared in Example 1 at different rates.

[0029] Figure 10 shows the rate performance of the membraneless two-phase decoupled low eutectic gel electrolyte Zn||MnO2 full battery prepared by Example 1, the membraneless decoupled hydrogel electrolyte Zn||MnO2 full battery prepared by Comparative Example 1, and the membrane liquid low eutectic solvent electrolyte Zn||MnO2 full battery prepared by Comparative Example 2.

[0030] Figure 11 shows the pH changes of the positive and negative electrolytes in the full battery of membraneless two-phase decoupling eutectic gel electrolyte Zn||MnO2 prepared in Example 1 and the full battery of membraneless decoupling hydrogel electrolyte Zn||MnO2 prepared in Comparative Example 1 during the charge and discharge cycle.

[0031] FIG12 is a charge-discharge polarization curve diagram of the Zn||MnO2 soft-pack battery prepared in Example 5-7 at different temperatures.

[0032] FIG13 shows the cycling stability of the Zn||MnO2 soft pack battery prepared in Example 6 at different temperatures.

[0033] FIG14 shows the cycle stability of the Zn||MnO2 soft pack battery prepared in Example 7 at -40°C.

[0034] FIG15 is a graph showing the experimental data of the Zn||MnO2 soft-pack battery prepared in Example 5 under different safety test conditions.

[0035] In the figure: 10, dual-phase decoupled eutectic gel electrolyte; 20, positive electrode sheet; 30, negative electrode sheet; 101, acidic eutectic gel electrolyte; 102, alkaline eutectic gel electrolyte. DETAILED DESCRIPTION

[0036] To facilitate understanding of the present application, the present application will be described in more detail below. However, it should be understood that the present application can be implemented in many different forms and is not limited to the embodiments or examples described herein. On the contrary, the purpose of providing these embodiments or examples is to make the understanding of the disclosure of the present application more thorough and comprehensive.

[0037] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those generally understood by those skilled in the art of the technical field of the present application. The terms used herein in the specification of the present application are only for the purpose of describing specific embodiments or embodiments and are not intended to limit the present application. The optional scope of the term "and / or" used herein includes any one of two or more related listed items, and also includes any and all combinations of related listed items, including any two related listed items, any more related listed items, or a combination of all related listed items.

[0038] As shown in Figure 1, the dual-phase decoupled eutectic gel electrolyte 10 provided in the present application has a double-layer structure, including an acidic eutectic gel electrolyte 101 and an alkaline eutectic gel electrolyte 102 stacked in layers; wherein the dispersion medium of the acidic eutectic gel electrolyte 101 includes at least an acidic eutectic solvent and a first metal salt; the dispersion medium of the alkaline eutectic gel electrolyte 102 includes at least an alkaline eutectic solvent and a second metal salt.

[0039] The present invention sets the structure of the dual-phase decoupled eutectic gel electrolyte 10 and uses an acidic deep eutectic solvent and an alkaline deep eutectic solvent as dispersion media respectively, so that the conductivity of the dual-phase decoupled eutectic gel electrolyte 10 is 3mS·cm -1 -10mS·cm -1 , activation energy is 0.01eV-1eV, metal ion migration number is 0.49--0.80, temperature resistance range is -60℃-80℃, electrochemical window is 2V-5V, elongation is 50%-1000%, it has excellent conductivity, high metal ion migration number, wide electrochemical window, wide temperature range tolerance and tensile properties, and can effectively avoid the crossover of hydrogen ions and hydroxide ions and the crossover of active metal ions in the positive and negative electrode electrolytes.

[0040] Optionally, the hydrogen bond acceptor in the acidic deep eutectic solvent is selected from at least one of choline chloride and betaine, the hydrogen bond donor is selected from at least one of formic acid, acetic acid, oxalic acid, and citric acid, and the molar ratio of the hydrogen bond acceptor to the hydrogen bond donor is 1:1-1:4.

[0041] Optionally, the hydrogen bond acceptor in the alkaline deep eutectic solvent is selected from at least one of choline chloride and betaine, the hydrogen bond donor is selected from at least one of ethylene glycol, glycerol, urea, ethanolamine, diethanolamine, triethanolamine, and isopropanolamine, and the molar ratio of the hydrogen bond acceptor to the hydrogen bond donor is 1:1-1:8.

[0042] It should be noted that the present application does not limit the pH of the acidic deep eutectic solvent and the alkaline deep eutectic solvent, nor does it limit the pH of the acidic deep eutectic gel electrolyte 101 and the alkaline deep eutectic gel electrolyte 102. However, the greater the difference in pH between the acidic deep eutectic gel electrolyte 101 and the alkaline deep eutectic gel electrolyte 102, the better the effect.

[0043] Therefore, when selecting an acidic deep eutectic solvent and an alkaline deep eutectic solvent for use in combination, a combination with a larger pH difference and a higher conductivity is preferably selected, and / or the dispersion medium of the acidic deep eutectic gel electrolyte 101 may optionally further include an acidic solution, and / or the dispersion medium of the alkaline deep eutectic gel electrolyte 102 may optionally further include an alkaline solution. The use of acidic and alkaline solutions can expand the pH difference and improve the conductivity.

[0044] Considering that inorganic acids and inorganic bases have better solubility, optionally, the acidic solution is selected from an aqueous solution of an inorganic acid, including at least one of a hydrochloric acid solution, a sulfuric acid solution or a nitric acid solution, and the molar concentration of the acidic solution is 0.5 mol·L -1 12 mol·L -1 The alkaline solution is selected from an aqueous solution of an inorganic base, including at least one of a sodium hydroxide solution, a potassium hydroxide solution or a lithium hydroxide solution; the molar concentration of the alkaline solution is 0.5 mol·L -1 -9mol·L -1 .

[0045] It should be noted that although the aqueous solution of inorganic acid and the aqueous solution of inorganic base contain water, within a certain range, water does not destroy the structure of the low eutectic solvent, and also forms hydrogen bonds with the low eutectic solvent, thereby being bound in the low eutectic solvent. In addition, the acidic low eutectic solvent and the alkaline low eutectic solvent prepared in the present application are mutually incompatible two-phase media, and the phase interface spontaneously forms an ion-selective migration channel, so that the two-phase decoupled low eutectic gel electrolyte 10 of the present application does not produce the crossover of hydrogen ions and hydroxide ions and the crossover of active metal ions in the positive and negative electrolytes.

[0046] In order to improve the effect of the dual-phase decoupling eutectic gel electrolyte 10 of the present application, optionally, the mass fraction of the dispersion medium in the acidic eutectic gel electrolyte 101 is 70%-90%, and the mass fraction of the dispersion medium in the alkaline eutectic gel electrolyte 102 is 70%-90%. At the same time, in order to further control the water content, optionally, the molar concentration of the aqueous solution of the inorganic acid is 0.5 mol·L -1 -12mol·L -1 , and the concentration of acid in the dispersion medium of the acidic eutectic gel electrolyte 101 is 0.05 mol·L -1 -3.6 mol·L -1 The molar concentration of the aqueous solution of the inorganic base is 0.5 mol·L -1 -9mol·L -1 , and the concentration of alkali in the dispersion medium of the alkaline eutectic gel electrolyte 102 is 0.05 mol·L -1 -2.7 mol·L -1 .

[0047] The present application does not limit the selection of the first metal salt and the second metal salt. Optionally, the first metal salt and the second metal salt are independently selected from at least one of lithium salt, sodium salt, potassium salt, zinc salt, magnesium salt, aluminum salt, manganese salt, lead salt, and alum salt. At the same time, the first metal salt and the second metal salt can be the same or different, and can be selected according to the actual application scenario.

[0048] Optionally, in the dispersion medium of the acidic eutectic gel electrolyte 101, the concentration of the first metal salt is 0.5 mol·L -1 -3mol·L -1 In the dispersion medium of the alkaline eutectic gel electrolyte 101, the concentration of the second metal salt is 0.5 mol·L -1 -3mol·L -1 .

[0049] In addition, in the dual-phase decoupled eutectic gel electrolyte 10 of the present application, both the acidic eutectic gel electrolyte 101 and the alkaline eutectic gel electrolyte 102 have excellent interfacial adhesion, with adhesion strengths ranging from 10 kPa to 10,000 kPa. This ensures good interfacial compatibility between the two gel interfaces of the dual-phase decoupled eutectic gel electrolyte 10 and between the dual-phase decoupled eutectic gel electrolyte 10 and different electrodes, thereby ensuring efficient electrochemical performance.

[0050] In the dual-phase decoupled eutectic gel electrolyte 10 of the present application, the polymer network structure of the acidic eutectic gel electrolyte 101 is prepared using a first polymer monomer, and the polymer network structure of the alkaline eutectic gel electrolyte 102 is prepared using a second polymer monomer. The specific selection of the first polymer monomer and the second polymer monomer does not have a substantial impact on the performance of the dual-phase decoupled eutectic gel electrolyte 10. Therefore, the present application does not limit the selection of the first polymer monomer and the second polymer monomer. The first polymer monomer and the second polymer monomer are independently selected from at least one of a zwitterionic polymer monomer, a cationic polymer monomer, an anionic polymer monomer, or a non-ionic polymer monomer. At the same time, the first polymer monomer and the second polymer monomer can be the same or different.

[0051] Optionally, the zwitterionic polymer monomer is selected from at least one of 3-[N,N-dimethyl-[2-(2-methylprop-2-enoyloxy)ethyl]ammonium]propane-1-sulfonic acid inner salt, N-carboxymethyl-N,N-bis(2-hydroxyethyl)-1-dodecylammonium inner salt, 3-[[2-(methacryloyloxy)ethyl]dimethylammonium]propionate, and 2-methacryloyloxyethyl phosphoric acid bile; the cationic polymer monomer is selected from at least one of N,N,N-trimethyl-3-(2-methylallylamino)-1-propylammonium chloride and acryloyloxyethyltrimethylammonium chloride; the anionic polymer monomer is selected from at least one of sodium p-styrene sulfonate, 2-acrylamido-2-methylpropanesulfonic acid sodium salt solution, and 2-acrylamido-2-methylpropanesulfonic acid; and the nonionic polymer monomer is selected from at least one of acrylamide, N-(2-hydroxyethyl)acrylamide, N,N-dimethylacrylamide, and N-(3-dimethylaminopropyl)methacrylamide.

[0052] When zwitterionic polymer monomers are used, the electrical conductivity and interface adhesion of the dual-phase decoupled eutectic gel electrolyte 10 are relatively good, so both the first polymer monomer and the second polymer monomer can be zwitterionic polymer monomers.

[0053] The present application also provides a method for preparing the dual-phase decoupled eutectic gel electrolyte, comprising the following steps:

[0054] S1, respectively preparing a first precursor for preparing an acidic eutectic gel electrolyte and a second precursor for preparing an alkaline eutectic gel electrolyte;

[0055] S2, preparing the first precursor into an acidic low-melting eutectic gel electrolyte 101 and preparing the second precursor into an alkaline low-melting eutectic gel electrolyte 102, and then laminating the acidic low-melting eutectic gel electrolyte 101 and the alkaline low-melting eutectic gel electrolyte 102 to obtain a two-phase decoupled low-melting eutectic gel electrolyte 10; or, first preparing either the first precursor or the second precursor into a low-melting eutectic gel electrolyte, and then placing the other precursor on the low-melting eutectic gel electrolyte to prepare another low-melting eutectic gel electrolyte in situ to obtain a two-phase decoupled low-melting eutectic gel electrolyte 10.

[0056] In step S1, the first precursor is prepared using a first polymer monomer, a first cross-linking agent, a first photoinitiator, a first metal salt, and an acidic deep eutectic solvent, wherein the mass ratio of the first polymer monomer to the acidic deep eutectic solvent can be selected from 10:100 to 50:100, the mass ratio of the first cross-linking agent to the acidic deep eutectic solvent can be selected from 0.01:100 to 1:100, the mass ratio of the first photoinitiator to the acidic deep eutectic solvent can be selected from 1:100 to 10:100, and the concentration of the first metal salt in the first precursor can be selected from 0.3 mol·L -1 -2.3 mol·L -1 During preparation, heating is used to dissolve all the components in the first precursor. Optionally, the heating temperature is 50°C-100°C.

[0057] Optionally, when preparing the first precursor, an acidic solution is also used, the acidic solution is selected from an aqueous solution of an inorganic acid, and the mass ratio of the acidic solution to the acidic deep eutectic solvent is 1:9-3:7.

[0058] In step S1, the second precursor is prepared using a second polymer monomer, a second cross-linking agent, a second photoinitiator, a second metal salt, and an alkaline deep eutectic solvent, wherein the mass ratio of the second polymer monomer to the alkaline deep eutectic solvent can be selected from 10:100 to 50:100, the mass ratio of the second cross-linking agent to the alkaline deep eutectic solvent can be selected from 0.01:100 to 1:100, the mass ratio of the second photoinitiator to the alkaline deep eutectic solvent can be selected from 1:100 to 10:100, and the concentration of the second metal salt in the second precursor can be selected from 0.3 mol·L -1 -2.3 mol·L -1 During preparation, heating is used to dissolve all the components in the second precursor. Optionally, the heating temperature is 50°C-100°C.

[0059] Optionally, when preparing the second precursor, an alkaline solution is also used, the alkaline solution is selected from an aqueous solution of an inorganic base, and the mass ratio of the alkaline solution to the alkaline deep eutectic solvent is 1:9 to 3:7.

[0060] In step S1, the first cross-linking agent and the second cross-linking agent are independently selected from at least one of N,N'-methylenebisacrylamide or 1,6-hexanediol diacrylate; the first photoinitiator and the second photoinitiator are independently selected from at least one of 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone or phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide.

[0061] In step S2, the two-phase decoupled eutectic gel electrolyte 10 can be prepared in different ways. During in-situ preparation, the first precursor can be first prepared into an acidic eutectic gel electrolyte 101, and then the second precursor can be placed on the acidic eutectic gel electrolyte 101 to prepare the alkaline eutectic gel electrolyte 102 in situ. Alternatively, the second precursor can be first prepared into an alkaline eutectic gel electrolyte 102, and then the first precursor can be placed on the alkaline eutectic gel electrolyte 102 to prepare the acidic eutectic gel electrolyte 101 in situ.

[0062] In step S2, the wavelength of light used in the photo-initiated polymerization reaction can be selected to be 365 nm, and the illumination time can be selected to be 5 min-60 min.

[0063] The third aspect of the present application also provides an application of the dual-phase decoupled eutectic gel electrolyte in devices, wherein the devices include energy storage devices such as decoupled batteries, soft-pack batteries, flexible supercapacitors, or electronic devices such as flexible sensors.

[0064] As shown in Figure 2, the present application also provides a decoupling battery, which includes a positive electrode sheet 20, the two-phase decoupling low-melting eutectic gel electrolyte 10 and a negative electrode sheet 30 stacked in sequence, wherein the acidic low-melting eutectic gel electrolyte 101 in the two-phase decoupling low-melting eutectic gel electrolyte 10 is adhered to the positive electrode sheet 20, and the alkaline low-melting eutectic gel electrolyte 102 is adhered to the negative electrode sheet 30.

[0065] When the dual-phase decoupling eutectic gel electrolyte 10 of the present application is used in a decoupling battery, it can not only avoid the use of expensive ion-selective membranes and simplify the battery structure, but also break through the rate limitation of traditional decoupling electrolytes, so that the decoupling battery can achieve extremely fast charging under ultra-low temperature and high temperature conditions, and maintain high capacity and long cycle stability, and has good application prospects in the field of large-scale energy storage in a wide temperature range.

[0066] For example, when used in a zinc-manganese decoupling battery, the acid-base dual-phase decoupling eutectic gel electrolyte 10 of the present application can form an ion selective migration channel in situ to transfer Zn 2+ and OH - Confined in alkaline eutectic gel electrolyte 102, Mn 2+ and H + confined in an acidic eutectic gel electrolyte 101, while allowing K + and Cl - The contact interface between the acidic eutectic gel electrolyte 101 and the alkaline eutectic gel electrolyte 102 allows for a decoupled battery design and avoids ion crossover. Thus, deposition and dissolution reactions occur at both the positive and negative electrodes, enabling a 2e manganese ion transfer reaction, achieving a capacity of 607 mAh g -1High specific capacity, close to 616 mAh g -1 At the same time, the active metal ions in both the positive and negative electrodes have only half the ion migration path, which accelerates the ion transport kinetics, thus facilitating extremely fast charging, enabling it to have excellent extremely fast charging capability (10-min / 6C) and excellent cycle stability (>1000 cycles) under both high and low temperature conditions.

[0067] As shown in Figure 3, the present application also provides a decoupled soft-pack battery, comprising a battery core and a battery shell, wherein the battery core of the decoupled soft-pack battery comprises at least one positive electrode sheet 20 and at least one negative electrode sheet 30, the positive electrode sheets 20 and the negative electrode sheets 30 are alternately stacked in sequence, and the two-phase decoupling low-melting gel electrolyte 20 is sandwiched between the adjacent positive electrode sheets 20 and the negative electrode sheets 30, the acidic low-melting gel electrolyte 101 in the two-phase decoupling low-melting gel electrolyte 20 is adhered to the positive electrode sheet 20, and the alkaline low-melting gel electrolyte 102 is adhered to the negative electrode sheet 30.

[0068] In the battery cell, the sum of the number of positive electrode sheets 20 and negative electrode sheets 30 is greater than two. There is no specific limitation and the number can be selected as needed. As shown in the embodiment of FIG3a , the battery cell includes two positive electrode sheets 20 and two negative electrode sheets 30 . As shown in the embodiment of FIG3b , the battery cell includes two positive electrode sheets 20 and three negative electrode sheets 30 .

[0069] Optionally, the battery shell is selected from aluminum-plastic film.

[0070] For example, when the decoupled soft-pack battery is a zinc-based decoupled soft-pack battery, the positive electrode sheet 20 includes a current collector and an active material deposited on the current collector, the current collector is selected from carbon cloth, carbon felt or carbon paper, etc., the active material is selected from MnO2, polyaniline, PbO2 or V2O5, etc., and the negative electrode sheet 30 can be selected as a zinc sheet with a thickness of 0.01mm-1mm.

[0071] The active material in the positive electrode sheet 20 can be prepared by an electrochemical deposition method. For example, the electrochemical deposition method of MnO2 is as follows: prepare a metal salt solution such as manganese sulfate, manganese chloride, manganese nitrate, manganese acetate, or manganese formate as a deposition liquid, place the current collector in the deposition liquid, deposit it under constant pressure for 5 h to 12 h, and then place it in a vacuum drying oven at 60 ° C to 100 ° C for 4 h to 12 h to obtain a positive electrode sheet. The applied voltage range is 2.5 V to 3.0 V, and the double-sided density of the positive electrode sheet is 10 mg cm -2 -90mg cm -2 .

[0072] Specifically, when assembling a zinc-based decoupled soft-pack battery with a high capacity of 1Ah-100Ah, a positive electrode sheet with a size of 10cm×10cm-15cm×15cm is selected, and the double-sided density of the positive electrode sheet is 10mg cm –2 -90mg cm –2 , select zinc foil with a size of 10cm×10cm-15cm×15cm as the negative electrode material, alternately stack 2-51 negative electrode sheets 30 and 1-50 positive electrode sheets 20 in sequence, and sandwich the two-phase decoupled low eutectic gel electrolyte 20 between adjacent positive electrode sheets 20 and negative electrode sheets 30 to form a battery core.

[0073] The zinc-based decoupled soft-pack battery of the present application has a charge and discharge rate of 0.1C 60C, an extremely fast charging time as low as 1min, a cycle number of 500-5000 cycles, an operating temperature range of -60℃-80℃, a high capacity of 1Ah-100Ah, and a capacity of up to 180Wh kg –1 -300Wh kg –1 high energy density.

[0074] Therefore, the use of the dual-phase decoupled eutectic gel electrolyte of the present application can realize the assembly of soft-pack batteries with high capacity and high energy density, which have excellent comprehensive electrochemical performance and a wide operating temperature range, especially ultra-low temperature and extremely fast charging performance, such as the extremely fast charging time at minus 40°C is 10min-15min. At the same time, the soft-pack battery is inexpensive and has intrinsic safety. It can withstand bending, impact, puncture, shear damage, burning and water immersion, and has good application prospects in the fields of large-scale energy storage with a wide temperature range, electric vehicles, portable energy storage, etc.

[0075] Hereinafter, the dual-phase decoupled eutectic gel electrolyte, its preparation method and application will be further described through the following specific examples.

[0076] Example 1

[0077] Choline chloride and formic acid were weighed in a molar ratio of 1:2 in a glass vial, heated at 60° C. and stirred for 2 h to form a homogeneous transparent solution, and then naturally cooled to room temperature to obtain an acidic deep eutectic solvent.

[0078] Choline chloride, ethanolamine, and ethylene glycol were weighed in a molar ratio of 1:1:4 in a glass vial, heated at 60° C. and stirred for 2 h to form a homogeneous transparent solution, and then naturally cooled to room temperature to obtain an alkaline deep eutectic solvent.

[0079] Accurately weigh 295.9 mg of Mn(Ac)2, 350 mg of 3-[N,N-dimethyl-[2-(2-methylprop-2-enoyloxy)ethyl]ammonium]propane-1-sulfonic acid inner salt, 22.4 mg of 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone, 2.5 mg of N,N'-methylenebisacrylamide, 300 mg of H2SO4 (9M) solution, and 700 mg of an acidic deep eutectic solvent into a glass vial. After heating until completely dissolved, the solution was irradiated under a UV lamp with a wavelength of 365 nm for 11 min to obtain an acidic deep eutectic gel electrolyte.

[0080] Accurately weigh 384 mg of Zn(Ac)2, 300 mg of 3-[N,N-dimethyl-[2-(2-methylprop-2-enoyloxy)ethyl]ammonium]propane-1-sulfonic acid inner salt, 22.4 mg of 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone, 1.2 mg of N,N'-methylenebisacrylamide, 100 mg of KOH (2M) solution, and 900 mg of alkaline deep eutectic solvent in a glass vial. After heating until completely dissolved, the solution was poured onto the acidic deep eutectic gel electrolyte and irradiated under a UV lamp with a wavelength of 365 nm for 6 min to obtain a dual-phase decoupled deep eutectic gel electrolyte.

[0081] Example 2

[0082] Accurately weigh 188.8 mg of MnCl2, 350 mg of 3-[N,N-dimethyl-[2-(2-methylprop-2-enoyloxy)ethyl]ammonium]propane-1-sulfonic acid inner salt, 22.4 mg of 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone, 2.5 mg of N,N'-methylenebisacrylamide, 300 mg of HCl (9M) solution, and 700 mg of the acidic deep eutectic solvent prepared in Example 1 into a glass vial. After heating until completely dissolved, the mixture was irradiated under a UV lamp with a wavelength of 365 nm for 11 min to obtain an acidic deep eutectic gel electrolyte.

[0083] Accurately weigh 238.6 mg of ZnCl2, 300 mg of 3-[N,N-dimethyl-[2-(2-methylprop-2-enoyloxy)ethyl]ammonium]propane-1-sulfonic acid inner salt, 22.4 mg of 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone, 1.2 mg of N,N'-methylenebisacrylamide, 100 mg of NaOH (2M) solution, and 900 mg of the alkaline deep eutectic solvent prepared in Example 1 into a glass vial. After heating until completely dissolved, the mixture was irradiated under a UV lamp with a wavelength of 365 nm for 6 min to obtain an alkaline deep eutectic gel electrolyte.

[0084] The acidic eutectic gel electrolyte and the alkaline eutectic gel electrolyte are pasted together to obtain a dual-phase decoupling eutectic gel electrolyte.

[0085] Example 3

[0086] Accurately weigh 384 mg of Zn(Ac)2, 300 mg of acrylamide, 22.4 mg of 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone, 1.2 mg of N,N'-methylenebisacrylamide, 100 mg of KOH (2M) solution, and 900 mg of the alkaline deep eutectic solvent prepared in Example 1 into a glass vial. After heating until completely dissolved, the mixture was irradiated under a UV lamp with a wavelength of 365 nm for 5 minutes to obtain an alkaline deep eutectic gel electrolyte.

[0087] Accurately weigh 295.9 mg of Mn(Ac)2, 350 mg of acrylamide, 22.4 mg of 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone, 2.5 mg of N,N'-methylenebisacrylamide, 300 mg of H2SO4 (9M) solution, and 700 mg of the acidic deep eutectic solvent prepared in Example 1 into a glass vial. After heating until completely dissolved, the solution was poured onto the alkaline deep eutectic gel electrolyte and irradiated under a UV lamp with a wavelength of 365 nm for 8 min to obtain a dual-phase decoupled deep eutectic gel electrolyte.

[0088] Example 4

[0089] Accurately weigh 384 mg of Zn(Ac)2, 300 mg of 3-[N,N-dimethyl-[2-(2-methylprop-2-enoyloxy)ethyl]ammonium]propane-1-sulfonic acid inner salt, 22.4 mg of 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone, 1.2 mg of N,N'-methylenebisacrylamide, 100 mg of KOH (2M) solution, and 900 mg of the alkaline deep eutectic solvent prepared in Example 1 into a glass vial. After heating until completely dissolved, the mixture was irradiated under a UV lamp with a wavelength of 365 nm for 10 min to obtain an alkaline deep eutectic gel electrolyte.

[0090] Accurately weigh 295.9 mg of Mn(Ac)2, 350 mg of 3-[N,N-dimethyl-[2-(2-methylprop-2-enoyloxy)ethyl]ammonium]propane-1-sulfonic acid inner salt, 22.4 mg of 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone, 2.5 mg of N,N'-methylenebisacrylamide, 300 mg of H2SO4 (9M) solution, and 700 mg of the acidic deep eutectic solvent prepared in Example 1 into a glass vial. After heating until completely dissolved, the solution was poured onto the alkaline deep eutectic gel electrolyte and irradiated under a UV lamp with a wavelength of 365 nm for 10 min to obtain a dual-phase decoupled deep eutectic gel electrolyte.

[0091] Example 5

[0092] Choline chloride and acetic acid were weighed in a molar ratio of 1:2 in a glass vial, heated at 60° C. and stirred for 2 h to form a homogeneous transparent solution, and then naturally cooled to room temperature to obtain an acidic deep eutectic solvent.

[0093] Choline chloride, triethanolamine, and ethylene glycol were weighed in a molar ratio of 1:1:4 in a glass vial, heated at 60° C. and stirred for 2 h to form a homogeneous transparent solution, and then naturally cooled to room temperature to obtain an alkaline deep eutectic solvent.

[0094] Accurately weigh 384 mg of Zn(Ac)2, 300 mg of 3-[N,N-dimethyl-[2-(2-methylprop-2-enoyloxy)ethyl]ammonium]propane-1-sulfonic acid inner salt, 22.4 mg of 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone, 1.2 mg of N,N'-methylenebisacrylamide, 100 mg of KOH (2M) solution, and 900 mg of an alkaline deep eutectic solvent in a glass vial. After heating until completely dissolved, the mixture is irradiated under a UV lamp with a wavelength of 365 nm for 6 min to obtain an alkaline deep eutectic gel electrolyte.

[0095] Accurately weigh 295.9 mg of Mn(Ac)2, 350 mg of 3-[N,N-dimethyl-[2-(2-methylprop-2-enoyloxy)ethyl]ammonium]propane-1-sulfonic acid inner salt, 22.4 mg of 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone, 2.5 mg of N,N'-methylenebisacrylamide, 300 mg of H2SO4 (9M) solution, and 700 mg of acidic deep eutectic solvent in a glass vial. After heating until completely dissolved, the solution was poured on the above-mentioned alkaline deep eutectic gel electrolyte and irradiated under ultraviolet light with a wavelength of 365 nm for 11 minutes to obtain a dual-phase decoupled deep eutectic gel electrolyte.

[0096] Example 6

[0097] Different from Example 4, in Example 6, no KOH solution is added in the preparation of the alkaline eutectic gel electrolyte, and no H2SO4 solution is added in the preparation of the acidic eutectic gel electrolyte, thereby obtaining a two-phase decoupled eutectic gel electrolyte.

[0098] Comparative Example 1

[0099] Accurately weigh 384 mg of Zn(Ac)2, 300 mg of 3-[N,N-dimethyl-[2-(2-methylprop-2-enoyloxy)ethyl]ammonium]propane-1-sulfonic acid inner salt, 22.4 mg of 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone, 1.2 mg of N,N'-methylenebisacrylamide, 100 mg of KOH (2M) solution, and 900 mg of H2O in a glass vial. After heating until completely dissolved, the mixture was irradiated under a UV lamp with a wavelength of 365 nm for 20 min to obtain an alkaline hydrogel electrolyte.

[0100] Accurately weigh 295.9 mg of Mn(Ac)2, 350 mg of 3-[N,N-dimethyl-[2-(2-methylprop-2-enoyloxy)ethyl]ammonium]propane-1-sulfonic acid inner salt, 22.4 mg of 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone, 2.5 mg of N,N'-methylenebisacrylamide, 300 mg of H2SO4 (9M) solution, and 700 mg of H2O in a glass vial. After heating until completely dissolved, the solution was poured on the above-mentioned alkaline hydrogel electrolyte and irradiated under a UV lamp with a wavelength of 365 nm for 10 min to obtain a decoupled hydrogel electrolyte.

[0101] Performance tests were performed on the dual-phase decoupling eutectic gel electrolytes of Examples 1 to 6 and the decoupling hydrogel electrolyte of Comparative Example 1. The results are shown in Figures 4 to 7 and Table 1.

[0102] In Figure 4, a represents the tensile curve of the acidic low-melting eutectic gel electrolyte, b represents the tensile curve of the alkaline low-melting eutectic gel electrolyte, and c represents the tensile curve of the dual-phase decoupled low-melting eutectic gel electrolyte. It can be seen from the figure that the uniaxial tensile rates of the acidic low-melting eutectic gel electrolyte, the alkaline low-melting eutectic gel electrolyte and the dual-phase decoupled low-melting eutectic gel electrolyte at room temperature are 579%, 355% and 512%, respectively, and the tensile properties are excellent.

[0103] In Figure 5, a is the adhesion test diagram between the two-phase decoupled low-melting eutectic gel electrolyte and the positive electrode current collector, b is the adhesion test diagram between the two-phase decoupled low-melting eutectic gel electrolyte and the negative electrode current collector, and c is the adhesion test diagram between the double-layer gel interface of the two-phase decoupled low-melting eutectic gel electrolyte. It can be seen from the figure that the two-phase decoupled low-melting eutectic gel electrolyte has excellent adhesion.

[0104] In Figure 6, a is the activation energy curve of the two-phase decoupled low-melting eutectic gel electrolyte, and b is the activation energy curve of the decoupled hydrogel electrolyte. It can be seen from the figure that the activation energy of the two-phase decoupled low-melting eutectic gel electrolyte is 0.06eV, which is much lower than the activation energy of the decoupled hydrogel electrolyte of 0.16eV.

[0105] In Figure 7, a is the acid-base two-phase decoupled low-melting eutectic gel electrolyte, and b is the electrochemical window of the decoupled hydrogel electrolyte. It can be seen from the figure that the electrochemical stability window (3.40 V) of the two-phase decoupled low-melting eutectic gel electrolyte is wider than that of the decoupled hydrogel electrolyte (3.02 V).

[0106] Table 1

[0107] Application Example 1

[0108] Preparation of a decoupled eutectic gel full battery: A mixed solution of manganese acetate, ammonium acetate, and distilled water was used as the electrodeposition solution, and nanostructured manganese dioxide was electrochemically deposited on the carbon cloth as the positive electrode sheet, and a zinc sheet was used as the negative electrode sheet. The dual-phase decoupled eutectic gel electrolyte of Example 1 was sandwiched between the positive and negative electrode sheets to obtain a Zn||MnO2 full battery.

[0109] Comparative Application Example 1

[0110] Preparation of a decoupled hydrogel full battery: A mixed solution of manganese acetate, ammonium acetate, and distilled water was used as the electrodeposition solution, and nanostructured manganese dioxide was electrochemically deposited on the carbon cloth as the positive electrode sheet, and a zinc sheet was used as the negative electrode sheet. The decoupled hydrogel electrolyte of Comparative Example 1 was sandwiched between the positive and negative electrode sheets to obtain a Zn||MnO2 full battery.

[0111] Application Comparative Example 2

[0112] Preparation of a membrane liquid decoupling low eutectic solvent full battery: using the acidic low eutectic solvent and alkaline low eutectic solvent in Example 1, Mn(Ac)2 and Zn(Ac)2 were added respectively. After dissolution, the solutions were added to the positive electrode pool and the negative electrode pool respectively, separated by a bipolar ion selective membrane in the middle, and nanostructured manganese dioxide was electrochemically deposited on the carbon cloth as the positive electrode plate, and the zinc plate was used as the negative electrode plate to assemble a membrane decoupling low eutectic solvent Zn||MnO2 full battery.

[0113] Performance tests were conducted on the batteries of Application Example 1 and Comparative Examples 1-2, and the results are shown in FIG8-FIG11 and Table 2.

[0114] Figure 8 shows the open circuit voltage of the prepared membraneless two-phase decoupling low eutectic gel electrolyte Zn||MnO2 full battery at room temperature. It can be seen from the figure that the prepared membraneless two-phase decoupling low eutectic gel electrolyte Zn||MnO2 full battery has a voltage of up to 2.1V.

[0115] In Figure 9, a is the discharge polarization curve of the dual-phase decoupled low-melting gel electrolyte Zn||MnO2 full battery at a rate of 0.5C, b is the discharge polarization curve of the dual-phase decoupled low-melting gel electrolyte Zn||MnO2 full battery at a rate of 1C, c is the discharge polarization curve of the dual-phase decoupled low-melting gel electrolyte Zn||MnO2 full battery at a rate of 6C, and d is the discharge polarization curve of the dual-phase decoupled low-melting gel electrolyte Zn||MnO2 full battery at a rate of 10C. Polarization curves, e is the discharge polarization curve of the dual-phase decoupling eutectic gel electrolyte Zn||MnO2 full battery at a rate of 15C, f is the discharge polarization curve of the dual-phase decoupling eutectic gel electrolyte Zn||MnO2 full battery at a rate of 30C, and g is the discharge polarization curve of the dual-phase decoupling eutectic gel electrolyte Zn||MnO2 full battery at a rate of 60C. It can be seen from the figure that at a rate not exceeding 1C, the discharge specific capacity is close to the theoretical value (616mAh g –1 ), and can maintain 407mAh g at rates up to 60C –1 High capacity.

[0116] In Figure 10, i is the rate cycle diagram of the membrane liquid low eutectic solvent electrolyte Zn||MnO2 full battery, ii is the rate cycle diagram of the two-phase decoupled low eutectic gel electrolyte Zn||MnO2 full battery, and iii is the rate cycle diagram of the decoupled hydrogel electrolyte Zn||MnO2 full battery. a is 0.5C, b is 1C, c is 6C, d is 10C, e is 15C, f is 30C, g is 60C, and h is back to 1C again. It can be seen from the figure that the two-phase decoupled low eutectic gel electrolyte Zn||MnO2 full battery exhibits good rate cyclability and can achieve extremely fast charging of the battery, while the rate cycles of the decoupled hydrogel electrolyte and the membrane liquid low eutectic solvent electrolyte Zn||MnO2 full battery both decay rapidly at 6C.

[0117] In Figure 11, a is the pH change of the acidic electrolyte of the dual-phase decoupled low-melting gel electrolyte Zn||MnO2 full battery during the charge and discharge cycle, b is the pH change of the acidic electrolyte of the decoupled hydrogel electrolyte Zn||MnO2 full battery during the charge and discharge cycle, c is the pH change of the alkaline electrolyte of the decoupled hydrogel electrolyte Zn||MnO2 full battery during the charge and discharge cycle, and d is the pH change of the alkaline electrolyte of the dual-phase decoupled low-melting gel electrolyte Zn||MnO2 full battery during the charge and discharge cycle. It can be seen from the figure that the pH value of the dual-phase decoupled low-melting gel electrolyte has no obvious change during the cycle of 1000 times, which proves that it has good stability and can avoid H + / OH – The pH value of the decoupled hydrogel electrolyte has changed significantly within only 300 cycles, proving that H + / OH –The ion crosstalk is serious, which greatly reduces its lifespan.

[0118] Table 2

[0119] Application Example 2

[0120] Prepare a 5cm x 5cm carbon cloth and a deposition solution consisting of ammonium acetate, Mn(Ac)2, and H2O in a mass ratio of 1:20:500. Place the carbon cloth in the deposition solution and deposit at 3V for 7 hours. Then, dry it in a vacuum oven at 60°C for 12 hours to obtain the positive electrode sheet.

[0121] Prepare a 5cm x 5cm zinc foil with a thickness of 0.05mm. Finely sand it with sandpaper to obtain the negative electrode sheet.

[0122] Two negative electrode sheets, two dual-phase decoupled eutectic gel electrolytes prepared in Example 1, and one positive electrode sheet were stacked, secured with specialized tape, and wrapped with an 8 cm × 12 cm aluminum-plastic film. The film was sealed with a sealing machine to produce a 1 Ah wide-temperature range, extremely fast-charging, long-cycle, intrinsically safe Zn||MnO2 soft-pack battery.

[0123] Application Example 3

[0124] Different from Application Example 2, Application Example 3 selects carbon paper loaded with polyaniline as the positive electrode sheet and zinc foil with a thickness of 0.1 mm as the negative electrode sheet to obtain a 1Ah wide temperature range, extremely fast charging, long cycle, intrinsically safe Zn||polyaniline soft-pack battery.

[0125] Application Example 4

[0126] Different from Application Example 2, Application Example 4 selects carbon felt loaded with PbO2 as the positive electrode sheet and zinc foil with a thickness of 0.08 mm as the negative electrode sheet to obtain a 1Ah wide temperature range, extremely fast charging, long cycle, intrinsically safe Zn||PbO2 soft-pack battery.

[0127] Application Example 5

[0128] Prepare a 10 cm x 10 cm carbon cloth and a deposition solution consisting of ammonium acetate, Mn(Ac)2, and H2O in a mass ratio of 30:1:500. Place the carbon cloth in the deposition solution and deposit at 3 V for 7 hours. Then, dry it in a vacuum oven at 60°C for 12 hours to obtain the positive electrode sheet.

[0129] Prepare a 10cm x 10cm zinc foil with a thickness of 0.05mm. Finely sand it with sandpaper to obtain the negative electrode sheet.

[0130] Two negative electrode sheets, two dual-phase decoupled eutectic gel electrolytes prepared in Example 1, and one positive electrode sheet were stacked, secured with specialized tape, and wrapped with a 12 cm × 25 cm aluminum-plastic film. The film was sealed with a sealing machine to produce a 5Ah wide-temperature range, extremely fast-charging, long-cycle, intrinsically safe Zn||MnO2 soft-pack battery.

[0131] Application Example 6

[0132] Different from Application Example 5, the constant pressure deposition time of the positive electrode sheet in Application Example 6 is reduced to 8h, and the number of positive electrode sheets, two-phase decoupled low-melting gel electrolyte, and negative electrode sheets is increased to 6, 12, and 7 sheets, which are stacked in sequence and soft-pack packaged to obtain a 20Ah wide temperature range, extremely fast charging, high capacity, long cycle, intrinsically safe Zn||MnO2 soft-pack battery.

[0133] Application Example 7

[0134] Different from Application Example 5, the constant pressure deposition time of the positive electrode sheet in Application Example 7 is reduced to 6h, and the number of positive electrode sheets, two-phase decoupled low-melting gel electrolyte, and negative electrode sheets is increased to 16, 32, and 17 sheets, which are stacked in sequence and soft-pack packaged to obtain a 50Ah wide temperature range, extremely fast charging, high capacity, long cycle, intrinsically safe Zn||MnO2 soft-pack battery.

[0135] The performance tests were performed on the decoupled soft-pack batteries of Application Example 4 to Application Example 7, and the results are shown in Figures 12 to 15 and Table 3.

[0136] In Figure 12, a is the discharge polarization curve of the 5Ah Zn||MnO2 soft-pack battery at -40°C, b is the discharge polarization curve of the 5Ah Zn||MnO2 soft-pack battery at 25°C, c is the discharge polarization curve of the 5Ah Zn||MnO2 soft-pack battery at 60°C, d is the discharge polarization curve of the 20Ah Zn||MnO2 soft-pack battery at -40°C, e is the discharge polarization curve of the 20Ah Zn||MnO2 soft-pack battery at 25°C, f is the discharge polarization curve of the 20Ah Zn||MnO2 soft-pack battery at 60°C, g is the discharge polarization curve of the 50Ah Zn||MnO2 soft-pack battery at -40°C, h is the discharge polarization curve of the 50Ah Zn||MnO2 soft-pack battery at 25°C, and i is the discharge polarization curve of the 50Ah The discharge polarization curve of the Zn||MnO2 soft-pack battery at 60°C. As can be seen from the figure, the Zn||MnO2 soft-pack battery can achieve high battery capacity in a wide temperature range.

[0137] In Figure 13, a is a cyclic stability data diagram of a 20Ah Zn||MnO2 soft-pack battery under 10-mim / 6C charge and discharge conditions at 60°C, b is a cyclic stability data diagram of a 20Ah Zn||MnO2 soft-pack battery under 10-mim / 6C charge and discharge conditions at 25°C, c is a cyclic stability data diagram of a 20Ah Zn||MnO2 soft-pack battery under 10-mim / 6C charge and discharge conditions at -40°C, and d is a target parameter data diagram of the U.S. Department of Energy for ultra-fast charging batteries. It can be seen from the figure that the energy density of the 20Ah Zn||MnO2 soft-pack battery at 60°C, 25°C, and -40°C can reach 280Wh kg –1 、267Wh kg –1 、223Wh kg –1 , the cycle stability exceeds 1000 cycles and maintains 80% of the energy density, exceeding the US Department of Energy's requirement for ultra-fast charging batteries greater than 180Wh kg –1 , with a target of 500 cycles at 80% energy retention.

[0138] Figure 14 shows the cycle stability data of a 50Ah Zn||MnO2 soft pack battery under 15-min / 4C charge and discharge conditions at -40°C. It can be seen from the figure that the 50Ah Zn||MnO2 soft pack battery can reach 211Wh kg at extremely low temperatures. –1 It has high energy density and maintains 80% of the energy density for more than 600 cycles, demonstrating the ability to charge extremely fast at extremely low temperatures.

[0139] In Figure 15, a is the voltage data diagram of the 5Ah Zn||MnO2 soft-pack battery during continuous bending for 3 minutes, b is the voltage data diagram of the 5Ah Zn||MnO2 soft-pack battery during continuous hammering for 3 minutes, c is the voltage data diagram of the 5Ah Zn||MnO2 soft-pack battery during two punctures within 3 minutes, d is the voltage data diagram of the 5Ah Zn||MnO2 soft-pack battery during two shearing processes within 3 minutes, e is the voltage data diagram of the 5Ah Zn||MnO2 soft-pack battery during continuous 1300°C flame burning for 2 minutes, and f is the voltage data diagram of the 5Ah Zn||MnO2 soft-pack battery after continuous immersion in water for 3 hours. It can be seen from the figure that the Zn||MnO2 soft-pack battery can maintain a stable voltage under various safety test conditions, showing extremely high safety.

[0140] Table 3

[0141] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0142] The above-described embodiments merely represent several implementation methods of the present application. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that a person skilled in the art could make various modifications and improvements without departing from the spirit of the present application, all of which fall within the scope of protection of the present application. Therefore, the scope of protection of the present patent application shall be determined by the appended claims.

Claims

1. A dual-phase decoupled eutectic gel electrolyte, It is characterized in that The dual-phase decoupled eutectic gel electrolyte comprises an acidic eutectic gel electrolyte and an alkaline eutectic gel electrolyte which are stacked; The dispersion medium of the acidic eutectic gel electrolyte comprises at least an acidic eutectic solvent and a first metal salt; the dispersion medium of the alkaline eutectic gel electrolyte comprises at least an alkaline eutectic solvent and a second metal salt.

2. The dual-phase decoupled eutectic gel electrolyte according to claim 1, in, The dispersion medium of the acidic eutectic gel electrolyte also includes an acidic solution; And / or, the dispersion medium of the alkaline eutectic gel electrolyte also includes an alkaline solution.

3. [Corrected 20.12.2023 in accordance with Rule 91] A dual-phase decoupled eutectic gel electrolyte according to claim 2, in, The dual-phase decoupling eutectic gel electrolyte also satisfies at least one of the following conditions: (1) The hydrogen bond acceptor in the acidic deep eutectic solvent is selected from at least one of choline chloride and betaine, the hydrogen bond donor is selected from at least one of formic acid, acetic acid, oxalic acid, and citric acid, and the molar ratio of the hydrogen bond acceptor to the hydrogen bond donor is 1:1 to 1:4; (2) the first metal salt is selected from at least one of lithium salt, sodium salt, potassium salt, zinc salt, magnesium salt, aluminum salt, manganese salt, lead salt and vanadium salt; (3) The acidic solution is selected from an aqueous solution of an inorganic acid, including at least one of a hydrochloric acid solution, a sulfuric acid solution or a nitric acid solution, with a molar concentration of 0.5 mol·mol·L -1 ~12mol·L -1 ; (4) The mass fraction of the dispersion medium in the acidic eutectic gel electrolyte is 70% to 90%, wherein the concentration of the acid in the dispersion medium is 0.05 mol·L -1 ~3.6mol·L -1 , the concentration of the first metal salt is 0.5 mol·L -1 ~3mol·L -1 ; (5) The hydrogen bond acceptor in the alkaline deep eutectic solvent is selected from at least one of choline chloride and betaine, the hydrogen bond donor is selected from at least one of ethylene glycol, glycerol, urea, ethanolamine, diethanolamine, triethanolamine, and isopropanolamine, and the molar ratio of the hydrogen bond acceptor to the hydrogen bond donor is 1:1 to 1:8; (6) the second metal salt is at least one selected from lithium salt, sodium salt, potassium salt, zinc salt, magnesium salt, aluminum salt, manganese salt, lead salt, and vanadium salt; (7) The alkaline solution is selected from an aqueous solution of an inorganic base, including at least one of a sodium hydroxide solution, a potassium hydroxide solution or a lithium hydroxide solution, with a molar concentration of 0.5 mol·mol·L -1 ~9mol·mol·L -1 ; (8) The mass fraction of the dispersion medium in the alkaline eutectic gel electrolyte is 70% to 90%, wherein the concentration of the alkali in the dispersion medium is 0.05 mol·L -1 ~2.7mol·mol·L -1 , the concentration of the second metal salt is 0.5 mol·L -1 ~3mol·L -1 .

4. The dual-phase decoupled eutectic gel electrolyte according to any one of claims 1 to 3, in, The polymer network structure of the acidic eutectic gel electrolyte is prepared using a first polymer monomer, and the polymer network structure of the alkaline eutectic gel electrolyte is prepared using a second polymer monomer, wherein the first polymer monomer and the second polymer monomer are independently selected from at least one of a zwitterionic polymer monomer, a cationic polymer monomer, an anionic polymer monomer or a non-ionic polymer monomer; The zwitterionic polymer monomer is selected from at least one of 3-[N,N-dimethyl-[2-(2-methylprop-2-enoyloxy)ethyl]ammonium]propane-1-sulfonic acid inner salt, N-carboxymethyl-N,N-bis(2-hydroxyethyl)-1-dodecylammonium inner salt, 3-[[2-(methacryloyloxy)ethyl]dimethylammonium]propionate, and 2-methacryloyloxyethyl phosphoric acid bile; the cationic polymer monomer is selected from at least one of N,N,N-trimethyl-3-(2-methylallylamino)-1-propylammonium chloride and acryloyloxyethyl trimethylammonium chloride; the anionic polymer monomer is selected from at least one of sodium p-styrene sulfonate, 2-acrylamido-2-methylpropanesulfonic acid sodium salt solution, and 2-acrylamido-2-methylpropanesulfonic acid; and the nonionic polymer monomer is selected from at least one of acrylamide, N-(2-hydroxyethyl)acrylamide, N,N-dimethylacrylamide, and N-(3-dimethylaminopropyl)methacrylamide.

5. A method for preparing the dual-phase decoupled eutectic gel electrolyte according to any one of claims 1 to 4, in, The following steps are involved: respectively preparing a first precursor for preparing an acidic eutectic gel electrolyte and a second precursor for preparing an alkaline eutectic gel electrolyte; The first precursor is prepared into an acidic eutectic gel electrolyte and the second precursor is prepared into an alkaline eutectic gel electrolyte, and then the acidic eutectic gel electrolyte and the alkaline eutectic gel electrolyte are laminated to obtain a dual-phase decoupled eutectic gel electrolyte; Alternatively, either the first precursor or the second precursor is first prepared into a low-melting eutectic gel electrolyte, and then the other precursor is placed on the low-melting gel electrolyte to in-situ prepare another low-melting gel electrolyte to obtain a two-phase decoupled low-melting gel electrolyte.

6. [Corrected 20.12.2023 in accordance with Rule 91] A method for preparing a dual-phase decoupled eutectic gel electrolyte according to claim 5, in, The first precursor is prepared by using a first polymer monomer, a first cross-linking agent, a first photoinitiator, a first metal salt and an acidic low eutectic solvent, wherein the mass ratio of the first polymer monomer to the acidic low eutectic solvent is 10:100 to 50:100, the mass ratio of the first cross-linking agent to the acidic low eutectic solvent is 0.01:100 to 1:100, the mass ratio of the first photoinitiator to the acidic low eutectic solvent is 1:100 to 10:100, and the concentration of the first metal salt in the first precursor is 0.3 mol·L -1 ~2.3mol·L -1 .

7. The method for preparing the dual-phase decoupled eutectic gel electrolyte according to claim 6, in, An acidic solution is also used when preparing the first precursor, and the mass ratio of the acidic solution to the acidic low eutectic solvent is 1:9 to 3:

7.

8. The method for preparing the dual-phase decoupled eutectic gel electrolyte according to claim 6, in, The first cross-linking agent is independently selected from at least one of N,N'-methylenebisacrylamide and 1,6-hexanediol diacrylate.

9. The method for preparing the dual-phase decoupled eutectic gel electrolyte according to claim 6, in, The first photoinitiator is selected from at least one of 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone and phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide.

10. [Corrected 20.12.2023 in accordance with Rule 91] A method for preparing a dual-phase decoupled eutectic gel electrolyte according to claim 5, in, The second precursor is prepared by using a second polymer monomer, a second cross-linking agent, a second photoinitiator, a second metal salt and an alkaline low eutectic solvent, wherein the mass ratio of the second polymer monomer to the alkaline low eutectic solvent is 10:100 to 50:100, the mass ratio of the second cross-linking agent to the alkaline low eutectic solvent is 0.01:100 to 1:100, the mass ratio of the second photoinitiator to the alkaline low eutectic solvent is 1:100 to 10:100, and the concentration of the second metal salt in the second precursor is 0.3 mol·L -1 ~2.3mol·L -1 .

11. The method for preparing the dual-phase decoupled eutectic gel electrolyte according to claim 10, in, When preparing the second precursor, an alkaline solution is also used, and the mass ratio of the alkaline solution to the alkaline low eutectic solvent is 1:9 to 3:

7.

12. The method for preparing the dual-phase decoupled eutectic gel electrolyte according to claim 10, in, The second crosslinking agent is selected from at least one of N,N'-methylenebisacrylamide and 1,6-hexanediol diacrylate.

13. The method for preparing the dual-phase decoupled eutectic gel electrolyte according to claim 10, in, The second photoinitiator is selected from at least one of 2-hydroxy-4′-(2-hydroxyethoxy)-2-methylpropiophenone and phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide.

14. Use of the dual-phase decoupled eutectic gel electrolyte according to any one of claims 1 to 4 in a device.

15. A decoupling battery, It is characterized in that The decoupling battery comprises a positive electrode sheet, a two-phase decoupling eutectic gel electrolyte as claimed in any one of claims 1 to 4, and a negative electrode sheet which are stacked in sequence, wherein the acidic low eutectic gel electrolyte in the two-phase decoupling low eutectic gel electrolyte is adhered to the positive electrode sheet, and the alkaline low eutectic gel electrolyte is adhered to the negative electrode sheet.

16. A decoupled soft pack battery, It is characterized in that The battery core of the decoupled soft-pack battery includes at least one positive electrode sheet and at least one negative electrode sheet, the positive electrode sheets and the negative electrode sheets are alternately stacked in sequence, and the two-phase decoupling low-melting gel electrolyte according to any one of claims 1 to 4 is sandwiched between adjacent positive electrode sheets and negative electrode sheets, and the acidic low-melting gel electrolyte in the two-phase decoupling low-melting gel electrolyte is adhered to the positive electrode sheet, and the alkaline low-melting gel electrolyte is adhered to the negative electrode sheet.

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