Bulk phase and interface integrated ionic migration control electrochemical system

Abstract

The invention relates to a bulk phase and interface integrated ionic migration control electrochemical system, which is characterized in that a bulk phase ionic migration control agent is added into an electrolyte, so that the correlation and synergism of an electrolyte phase and an electrode bulk phase are guaranteed; the bulk phase ion migration control agent and the water solvent have intermolecular interaction to keep a macroscopic uniform liquid phase, and a dynamic tunnel is formed between the interface ion migration control agents on the two sides, so that electrochemical active ions controllably migrate in a dynamic tunnel structure of an electrolyte liquid phase; when the electrochemical active ions reach the position near the interface of the electrolyte and the electrode, the electrochemical active ions are continuously guided and rectified under the cooperative control of electrolyte components, interface product components and electrode body phase components; meanwhile, the non-ionized auxiliary solute in the dynamic tunnel wall also modifies an electrolyte and electrode interface, so that a reversible adsorption layer is formed, solvation adjustment of the electrode and electrolyte interface is realized, and an interface side reaction caused by active water is inhibited.

Description

Technical Field

[0001] The invention belongs to the technical field of energy materials, and in particular relates to an electrochemical system for controlling ion migration with integrated bulk and interface. Background Art

[0002] Green, environmentally friendly, and low-carbon forms of renewable energy are gradually being introduced into daily production and life. On this basis, in order to make up for the typical characteristics of renewable energy, such as intermittent, volatile, and random nature, the new power operation mode of "source-grid-load-storage" is gradually being deployed and applied; among them, various forms of energy storage systems are an indispensable part. In terms of energy storage installed capacity, traditional pumped storage is the leader, and it has also extended to typical mechanical energy storage forms including compressed air energy storage, flywheel energy storage, and heavy object slide rail energy storage. Compared with these energy storage systems based on large-scale infrastructure, electrochemical energy storage, especially water-based electrochemical energy storage technology, has significant advantages such as flexible investment and construction, no geographical constraints, and high energy conversion efficiency. Therefore, it is considered to be one of the most promising next-generation energy storage systems.

[0003] Although aqueous batteries have extremely high research value and broad application prospects, in order to ultimately achieve the development and mass production of mature aqueous battery products, in-depth research on the main components of the battery is still needed, especially to solve a series of highly related scientific problems that currently exist in aqueous batteries, from the electrolyte liquid phase, through the electrolyte and electrode interface, to the electrode bulk phase. In summary, the main reasons for the failure of aqueous electrochemical energy storage devices are thermodynamic corrosion, surface passivation and kinetic dendrite growth at the interface between the electrolyte and the negative electrode; and structural collapse and irreversible dissolution of active materials at the interface between the electrolyte and the positive electrode. The core of the above problems is that it is difficult to achieve integrated migration control and solvation regulation of active ions at the interface and related bulk phases.

[0004] Specifically, in the bulk environment, conventional control methods mainly include the use of low-concentration functional additives, such as conventional corrosion inhibitors, levelers, molecular complexing agents, etc.; however, the above additives still cannot fundamentally avoid the disordered migration of active ions in the electrolyte liquid phase, but increase the difficulty of rectification and solvation regulation near the interface. At the interface, since the decomposition of aqueous battery solutes / solvents cannot form a highly stable interface deposition layer, the mainstream interface optimization method is an external modified coating; this solution usually gradually fails after defects in the coating, and has a weak correlation with the electrolyte liquid phase and the electrode bulk phase, and is an independent one-time adjustment method. In terms of the electrode bulk phase, conventional optimization schemes, such as negative electrode alloying design, reasonable construction of electron / ion conduction network, and stabilization design of positive active powder, all have certain improvement effects; however, as an important part of the electrochemical system, the positive and negative electrode bulk phases of this optimization scheme lack uniformity in the implementation strategy with other key components, so it is difficult to ensure the consistency and synergy of the optimization scheme.

[0005] In view of this, there is an urgent need for an ion migration control scheme that integrates the bulk and interface based on the coordinated design of electrolyte and electrode, so that it has a comprehensive control method that starts from the phase migration of active ions in the electrolyte liquid phase, through dynamic ion rectification and solvation regulation at the interface between electrolyte and electrode, and extends to the mass transfer and charge transfer control inside the electrode bulk phase. With a unified ion migration control approach, the compatibility and synergy of key electrochemical components can be achieved. Summary of the invention

[0006] The purpose of the present invention is to overcome the deficiencies in the prior art and provide an electrochemical system for ion migration control that integrates bulk and interface.

[0007] The electrochemical system for controlling ion migration with integrated bulk and interface includes: electrodes, water-based electrolyte E and solid-phase ion guide R; the water-based electrolyte E includes water solvent ES, bulk ion migration control agent E1, interface ion migration control agent E2 and ionizable electrochemical active component E3;

[0008] The solid-phase ion guide R is dispersed in the positive electrode and the negative electrode, and the interface products for ion rectification and solvation regulation generated by the interface ion migration controller E2 are attached to the surfaces of the positive electrode and the negative electrode;

[0009] The water-based electrolyte E is distributed between the interface products generated by the interface ion migration controller E2 on both sides, the bulk ion migration controller E1 forms a dynamic tunnel between the interface ion migration controller E2 on both sides, the water solvent ES and the ionizable electrochemically active component E3 are transported in the dynamic tunnel, and the ionizable electrochemically active component E3 is dispersed in the water solvent ES.

[0010] Preferably, the bulk ion migration controller E1 includes electrochemically active ions, auxiliary ions and non-ionized auxiliary solutes, the electrochemically active ions and auxiliary ions are ionophilic phases, the non-ionized auxiliary solutes are ionophobic phases, the ionophobic phases are distributed on the dynamic tunnel walls, and the ionophilic phases are distributed in the dynamic tunnels.

[0011] Preferably, the solid-phase ion conductor R accounts for 0.5 to 5 wt.% of the electrode mass, the metal cations in the solid-phase ion conductor R include at least one of magnesium, calcium, manganese, iron, cobalt, nickel, copper, zinc, aluminum, indium, titanium and zirconium, and the anions include at least one of oxalate ions, polyalkyl sulfonate ions, polyalkyl carboxylate ions, phosphate ions, phosphonate ions and phosphonate derivative ions.

[0012] Preferably, the bulk ion migration controller E1 includes at least two of polyols, polyol hydrocarbon ethers, thiols, alcohol amines, carbonamides, hydrocarbon ureas, thioureas, hydrocarbon amides, cyanamides, glucose, fructose, sucrose, galactose and hydrocarbon phosphates, and the molar ratio of the bulk ion migration controller E1 to the aqueous solvent ES is 1:10 to 5:1.

[0013] Preferably, the interfacial ion migration controller E2 includes at least one of silicate, alkoxysilane, unsaturated hydrocarbon amide, polyol acrylate, imidazole, alkyl imidazole and aromatic carboxylic acid, and the molar ratio of the interfacial ion migration controller E2 to the water solvent ES is 1:10 to 1:2.

[0014] Preferably, the ionizable electrochemically active component E3 includes at least one of soluble salts of lithium, sodium, potassium, zinc and ammonium cations, the anions of the ionizable electrochemically active component E3 include at least one of sulfate ion, formate ion, acetate ion, perchlorate ion, sulfonate ion, sulfonic acid derivative ion, sulfonimide ion and sulfonimide derivative ion, and the molar ratio of the ionizable electrochemically active component E3 to the aqueous solvent ES is 1:10 to 1:1.

[0015] The preparation method of the electrochemical system with integrated bulk and interface ion migration control comprises the following steps:

[0016] Step 1, adding bulk ion migration controller E1 to water solvent ES, stirring to obtain mixed solution A;

[0017] Step 2: Add the interfacial ion migration controller E2 to the mixed solution A and stir to obtain a mixed solution B;

[0018] Step 3, adding the ionizable electrochemically active component E3 to the mixed solution B, stirring to obtain a water-based electrolyte E, and adjusting the pH of the water-based electrolyte E to 6.0-9.0;

[0019] Step 4: adding a solid phase ion conductor R to the positive electrode slurry and the negative electrode slurry to prepare an electrode material;

[0020] Step 5: Assemble the water-based electrolyte E and the electrode materials to form an aqueous electrochemical energy storage device, thereby obtaining an electrochemical system with integrated bulk and interface ion migration control.

[0021] Preferably, in steps 1 to 3, the water-based electrolyte E is prepared at 40-80°C.

[0022] The beneficial effects of the present invention are:

[0023] 1) The present invention ensures the correlation and synergy between the electrolyte liquid phase and the electrode bulk phase by adding a bulk ion migration controller to the electrolyte. The bulk ion migration controller not only has intermolecular interactions with the water solvent to maintain a macroscopically uniform liquid phase, but also forms a dynamic tunnel between the interface ion migration controllers on both sides, so that the electrochemically active ions can controllably migrate in the dynamic tunnel structure of the electrolyte liquid phase; when the electrochemically active ions reach the vicinity of the interface between the electrolyte and the electrode, they are continuously guided and rectified under the coordinated control of the electrolyte components, the interface product components, and the electrode bulk phase components; at the same time, the non-ionized auxiliary solutes in the dynamic tunnel wall also modify the interface between the electrolyte and the electrode, thereby forming a reversible adsorption layer, realizing the solvation regulation of the interface between the electrode and the electrolyte, and inhibiting the interface side reactions caused by active water.

[0024] 2) The present invention adds a non-ionized interfacial ion migration controller to the electrolyte components, allowing it to infiltrate the solid surface of the electrode, causing spontaneous or electrochemically induced reactions to occur, generating interfacial products that can be used for ion rectification and solvation regulation, thereby enhancing interfacial ion migration and avoiding spontaneous reactions in the bulk phase, effectively inhibiting the irreversible effect of active water on the electrode reaction, and thereby effectively ensuring the uniformity of the interfacial reaction activity and the rectification of ions in the electrolyte liquid phase near the interface.

[0025] 3) The bulk ion migration controller interacts with the electrode solid phase based on hydrogen bonds to regulate the solvation of the interface; and the interface ion migration controller undergoes spontaneous or electrochemically induced reactions on the surface of the electrode solid phase to generate interface products that can be used for ion rectification and solvation regulation. Both use the main components of the electrolyte and do not require the introduction of additional additive components, thereby significantly reducing the conflict caused by multiple components and simplifying the difficulty and cost of electrolyte material selection; at the same time, a reversible adsorption layer is formed by the bulk ion migration controller and the interface products derived from the interface ion migration controller and the solid ion guide, so that the interface layer in the electrochemical system has the function of self-repairing during the charge and discharge process, thereby overcoming the problem of poor interface stability in aqueous electrochemical systems in the prior art. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 Schematic diagram of the electrochemical system with integrated bulk and interface ion migration control. DETAILED DESCRIPTION

[0027] The present invention is further described below in conjunction with embodiments. The description of the following embodiments is only used to help understand the present invention. It should be noted that for ordinary persons in the art, without departing from the principle of the present invention, the present invention can also be modified in some ways, and these improvements and modifications also fall within the scope of protection of the claims of the present invention.

[0028] Embodiment 1

[0029] As an example, Figure 1 As shown, this electrochemical system with integrated bulk and interface ion migration control is an aqueous electrochemical energy storage system, including lithium, sodium, potassium, zinc systems, and a mixed system containing 2 to 3 of these systems.

[0030] Specifically, it includes: electrodes, a water-based electrolyte E that can realize active ion phase migration control and has the ability to dynamically rectify ions and adjust solvation at the interface between the electrolyte and the electrode; and a solid-phase ion guide R that can assist the electrolyte in mass transfer and charge transfer control at the solid-liquid interface and in the solid phase.

[0031] The water-based electrolyte E comprises: a water solvent ES, a bulk ion migration controller E1, an interface ion migration controller E2, and an ionizable electrochemically active component E3.

[0032] The solid phase ion guide R is dispersed in the positive electrode and the negative electrode, and the interface products for ion rectification and solvation regulation generated by the interface ion migration controller E2 are attached to the surface of the positive electrode and the negative electrode. The water-based electrolyte E is distributed between the interface products generated by the interface ion migration controller E2 on both sides.

[0033] The bulk ion migration controller E1 has intermolecular interactions with the water solvent ES to maintain a macroscopically uniform liquid phase; and due to its weak molecular polarity, it forms a thermodynamically stable and ion-repellent dynamic connection cluster at the microscopic level. A dynamic tunnel is then formed between the ion migration controllers E2 on both sides of the interface, and the water solvent ES and the ionizable electrochemically active component E3 are transported in the dynamic tunnel, and the ionizable electrochemically active component E3 is dispersed in the water solvent ES.

[0034] The interfacial ion migration controller E2 is a non-ionized component, which is mainly dispersed in the molecular clusters of the bulk ion migration controller E1 and has strong wettability to the electrode solid phase. Therefore, spontaneous or electrochemically induced reactions can occur on the surface of the electrode solid phase, and interfacial products that can be used for ion rectification and solvation regulation are generated at the contact interface between the electrode solid phase and the water-based electrolyte E.

[0035] The water solvent ES accounts for 5 to 30 wt.% of the water-based electrolyte E; the pH range of the water-based electrolyte E is 6.0 to 9.0. Adding a certain concentration of water solvent ES can not only act as a diluent and a conductive agent, but also provide additional hydrogen bond donor / acceptor sites, which is beneficial to the interaction of various components in the electrolyte, thereby forming a macroscopically uniform state. The molar ratio of the bulk ion migration controller E1, the interface ion migration controller E2 and the ionizable electrochemically active component E3 to the water solvent ES is not less than 1:10.

[0036] The solid phase ion guide R is one or more solid phase ion guides having metal cations M n+ (n=2,3,4) electrochemically reversible solid phase component with exchange capacity.

[0037] The above strategies mainly involve two aspects: aqueous electrolyte and solid ion guides in the electrode phase. The core is to achieve controllable migration of electrochemically active ions in the dynamic tunnel structure of the electrolyte liquid phase. When the electrochemically active ions reach the vicinity of the electrolyte-electrode interface, they are continuously guided and rectified under the coordinated control of the electrolyte components, interface product components, and electrode phase components, and solvation is regulated at the same time to inhibit the interfacial side reactions caused by active water and allow the active ions to react uniformly and reversibly with the electrode interface.

[0038] Embodiment 2

[0039] As another embodiment, this embodiment 2 proposes, based on the embodiment 1, that in this electrochemical system of ion migration control with integrated bulk and interface, the material selection and function of the water-based electrolyte E are specifically as follows:

[0040] The bulk ion migration control agent E1 can be selected from at least two of polyols, polyol alkyl ethers, thiols, alcohol amines, carbonamides, alkyl ureas, thioureas, alkyl amides, cyanamides, glucose, fructose, sucrose, galactose, and alkyl phosphates. Preferably, the molar ratio of the bulk ion migration control agent E1 to the aqueous solvent ES is 1:10 to 5:1.

[0041] The bulk ion migration controller E1 has a weaker molecular polarity than the water solvent ES, and has a strong wettability to the electrode solid phase. It also contains at least one of the nitrogen, oxygen, sulfur, and phosphorus polar sites, which can interact with the interface products derived from the interface ion migration controller E2 and the solid phase ion guide R based on hydrogen bonds.

[0042] Specifically, in the water-based electrolyte E, the bulk ion migration controller E1 not only has intermolecular interactions with the water solvent ES to maintain a macroscopically uniform liquid phase, but also forms thermodynamically stable and ion-repelling dynamic connected clusters at the microscopic level due to weak molecular polarity. From a microscopic perspective, these thermodynamically stable and ion-repelling molecular clusters construct the structure of a dynamic tunnel, which is significantly different from the short-range disorder phenomenon in the "high entropy" electrolyte, and fully utilizes the dynamic long-range self-assembly of short-range ordered clusters at high concentrations: inside the dynamic tunnel is an ionophilic phase, which provides the main channel for ion transmission and contains a large number of concentrated electrochemically active ions and auxiliary ions; while the molecules that constitute the dynamic tunnel wall are ionophobic phases, which contain a large number of non-ionized auxiliary solutes, and are mainly used to modify the interface between the electrolyte and the electrode.

[0043] Bulk ion migration controller E1 can also be derived to modify the electrode interface. Specifically, since the molecular polarity of bulk ion migration controller E1 is weaker than that of water solvent ES, it has strong hydrophobicity and correspondingly has a strong wetting effect with the less hydrophilic solid electrode material. Bulk ion migration controller E1 contains polar adsorption sites of nitrogen, oxygen, sulfur, and phosphorus, which can interact with various types of solid materials in the electrode, including the interface products derived from the interface ion migration controller E2 and the solid ion guide R, based on hydrogen bonds, thereby forming a reversible adsorption layer, which is mainly used for solvation regulation of the interface between the electrode and the electrolyte.

[0044] Preferably, the interface ion migration controller E2 can be selected from at least one of silicate, alkoxysilane, unsaturated hydrocarbon amide, polyol acrylate, imidazole, alkyl imidazole, and aromatic carboxylic acid. Preferably, the molar ratio of the interface ion migration controller E2 to the aqueous solvent ES is 1:10 to 1:2.

[0045] It should be pointed out that the bulk ion migration controller E1 interacts with the electrode solid phase based on hydrogen bonds, which is used for interface solvation regulation; and the interface ion migration controller E2 reacts spontaneously or electrochemically on the surface of the electrode solid phase to generate interface products that can be used for ion rectification and solvation regulation. Both use the main components of the electrolyte and do not require the introduction of additional additive components, thereby significantly reducing the conflict caused by multiple components and simplifying the difficulty of selecting electrolyte materials. At the same time, the adsorption-type interface layer and the reaction-type interface layer obtained by the above method are significantly different from the conventional artificial interface layer. They have the function of self-repairing during the charging and discharging process, overcoming the difficulty of poor interface stability in the aqueous electrochemical system in the prior art.

[0046] The ionizable electrochemically active component E3 comprises at least one of soluble salts of lithium, sodium, potassium, zinc, and ammonium cations. Preferably, the anions are selected from at least one of sulfate ions, formate ions, acetate ions, perchlorate ions, sulfonic acid and its derivative ions, sulfonimide and its derivative ions. Preferably, the molar ratio of the ionizable electrochemically active component E3 to the aqueous solvent ES is 1:10 to 1:1. Since the electrochemically active component E3 proposed in the present invention does not contain high-concentration halide salts, it has extremely low corrosiveness compared to the active components widely used in the prior art.

[0047] It should be noted that the parts in this embodiment that are the same or similar to those in the first embodiment can be referenced to each other and will not be described in detail in this application.

[0048] Embodiment 3

[0049] As another embodiment, this embodiment 3 proposes, based on the embodiments 1 and 2, that in this electrochemical system of bulk and interface integrated ion migration control, the material selection and function of the solid phase ion guide R are specifically as follows:

[0050] The solid phase ion director R is one or more species having metal cations M n+ (n = 2, 3, 4) electrochemically reversible solid phase component with exchange capacity. Preferably, the metal cation M in the solid phase component n+ At least one of magnesium, calcium, manganese, iron, cobalt, nickel, copper, zinc, aluminum, indium, titanium and zirconium can be selected; the anion can be selected from at least one of oxalate ions, polyalkylsulfonate ions, polyalkylcarboxylate ions, phosphate ions, phosphonic acid and their derivative ions. This type of guiding agent R is a pre-prepared nano or micro powder, and is evenly dispersed in the bulk phase of the electrode. Under the action of insoluble and polar active sites, the rectification and homogenization of active ions can be achieved from the interface between the electrolyte and the electrode to the inside of the electrode bulk phase. The solid phase ion guiding agent R can also include metal cations M n+ The solid phase product formed with the interface ion migration control agent E2. This type of solid phase product is mainly prepared by adding preferred imidazole, alkyl imidazole, aromatic carboxylic acid, etc. to the electrode solid phase. When it contacts the electrolyte, it reacts with the metal cation M n+ The in-situ reaction forms a composite product of metal and organic matter. Adding a solid-phase ion guide R to the electrode can not only effectively rectify and homogenize the ions, but also help the in-situ storage of ions and reduce the long-range diffusion of reactive ions.

[0051] The bulk and interface integrated ion migration control strategy can be effectively applied to a wide range of electrochemical systems, including lithium, sodium, potassium, zinc systems, and mixed systems containing 2 to 3 of these systems. Accordingly, in the electrochemical system involved, the negative electrode active material may include metallic zinc and its alloys, as well as materials that can reversibly embed / extract any one or more of lithium, sodium, and potassium ions. Matchingly, the positive electrode active material may include materials that can reversibly embed / extract any one or more of lithium, sodium, potassium, zinc ions, and protons, as well as materials that undergo reversible phase change reactions due to the embedding / extraction of the above ions.

[0052] It should be noted that the parts in this embodiment that are the same or similar to those in Embodiments 1 and 2 can be referenced to each other and will not be described in detail in this application.

[0053] Embodiment 4

[0054] As another embodiment, this embodiment 4 proposes, on the basis of embodiments 1 to 3, a method for preparing an electrochemical system for ion migration control with integrated bulk and interface, including the preparation of a water-based electrolyte E and the preparation of an electrode:

[0055] In terms of electrolyte, in order to prepare a water-based electrolyte ES that controls the phase migration of active ions and can dynamically rectify ions and adjust solvation at the interface between the electrolyte and the electrode, the following steps are included:

[0056] Step 1: add bulk ion migration controller E1, namely, 7.2 kg of glucose and 7.44 kg of ethylene glycol, into 1.8 kg of pure water solvent at one time, stir for 30 minutes, and obtain mixed solution A.

[0057] Step 2: Add the interfacial ion migration controller E2, i.e., 2.1 kg of tetraethyl silicate, into the mixed solution A at one time, and stir for 30 minutes to obtain a mixed solution B.

[0058] Step 3: Add the ionizable electrochemically active component E3, namely, 2.4 kg of zinc acetate and 1.98 kg of lithium perchlorate, to the mixed solution B at one time, and stir for 4 hours to obtain a clear and transparent electrolyte, namely, a water-based electrolyte E.

[0059] In the above steps 1 to 3, stirring can be performed at room temperature, or preferably, the water-based electrolyte E is prepared at 40-80° C. to accelerate the homogenization of the components, and a condensation reflux device is used to prevent water evaporation.

[0060] Step 4: Optionally, add an appropriate amount of lithium hydroxide or acetic acid to the water-based electrolyte E to fine-tune the pH to 7.0.

[0061] In terms of electrodes, the negative electrode uses zinc alloy as the electrochemically active material, and the positive electrode uses lithium manganese oxide as the electrochemically active material. The specific preparation method is as follows:

[0062] Solid phase ion conductor R, namely, nano powder of polyallyl nickel sulfonate, is added to positive electrode slurry and negative electrode slurry respectively, wherein the polyallyl nickel sulfonate in the positive electrode slurry accounts for 0.5 wt.% of the electrode solid phase mass, and the polyallyl nickel sulfonate in the negative electrode slurry accounts for 1.5 wt.% of the electrode solid phase mass.

[0063] After the preparation of the water-based electrolyte E and the electrodes is completed, they are assembled into an aqueous electrochemical energy storage device.

[0064] Embodiment 5

[0065] As another embodiment, this embodiment 5 proposes, based on the embodiment 4, a method for preparing an electrochemical system for ion migration control with integrated bulk and interface:

[0066] When preparing the water-based electrolyte ES, the bulk ion migration controller E1 in step one of Example 4 is replaced by 3.7 kg of methyl urea and 6.66 kg of tetraethylene glycol dimethyl ether, the interface ion migration controller E2 in step two is replaced by 2.84 kg of acrylamide, and the ionizable electrochemically active component E3 in step three is replaced by 3.67 kg of zinc methanesulfonate and 3.42 kg of sodium acetate.

[0067] When preparing the electrode, zinc alloy is used as the electrochemically active material for the negative electrode, and Prussian blue derivative is used as the electrochemically active material for the positive electrode. Solid phase ion guide R, namely, nano powder of cobalt-coordinated dimethylimidazole (ZIF-67 type metal and organic framework material) is added to the positive electrode slurry and the negative electrode slurry respectively. Among them, ZIF-67 in the positive electrode slurry accounts for 1.5wt.% of the electrode solid phase mass, and ZIF-67 in the negative electrode slurry accounts for 1.0wt.% of the electrode solid phase mass.

[0068] It should be noted that the parts in this embodiment that are the same or similar to those in the fourth embodiment can be referenced to each other and will not be described in detail in this application.

[0069] Embodiment 6

[0070] As another embodiment, this embodiment 6 proposes, on the basis of the embodiment 4, a method for preparing an electrochemical system for ion migration control with integrated bulk and interface:

[0071] When preparing the water-based electrolyte ES, in Example 4, the bulk ion migration controller E1 in step one is replaced by 18 kg of formamide and 5.4 kg of fructose, the interface ion migration controller E2 in step two is replaced by 3.5 kg of acrylamide, and the ionizable electrochemically active component E3 in step three is replaced by 2.4 kg of zinc acetate and 1.98 kg of lithium perchlorate.

[0072] The preparation materials and methods of the electrodes are the same as those in Example 4.

[0073] It should be noted that the parts in this embodiment that are the same or similar to those in the fourth embodiment can be referenced to each other and will not be described in detail in this application.

[0074] Embodiment 7

[0075] As another embodiment, this embodiment 7 proposes, on the basis of the embodiment 4, a method for preparing an electrochemical system for ion migration control with integrated bulk and interface:

[0076] When preparing the water-based electrolyte ES, the bulk ion migration controller E1 in step 1 of Example 4 was replaced with 1.49 kg of triethanolamine and 0.38 kg of thiourea, and the interface ion migration controller E2 in step 2 was replaced with 1.13 kg of N-isopropylacrylamide.

[0077] Other materials and methods remained unchanged.

[0078] It should be noted that the parts in this embodiment that are the same or similar to those in the fourth embodiment can be referenced to each other and will not be described in detail in this application.

[0079] Comparative Example 1

[0080] As a comparative example, this comparative example 1 illustrates an electrolyte for a mixed electrochemical system of aqueous zinc and lithium containing a bulk ion migration controller E1, an interface ion migration controller E2, and an ionizable electrochemically active component E3. The difference from the embodiment is that the electrolyte in this comparative example is relatively dilute:

[0081] Step 1: add bulk ion migration controller E1, namely, 1.5 kg of glucose and 0.62 kg of ethylene glycol, into 3.6 kg of pure water solvent at one time, stir at room temperature for 30 minutes, and obtain mixed solution A.

[0082] Step 2: Add the interfacial ion migration controller E2, i.e., 0.42 kg of tetraethyl silicate, into the mixed solution A at one time, and stir at room temperature for 30 minutes to obtain a mixed solution B.

[0083] Step 3: Add the ionizable electrochemically active component E3, namely, 0.8 kg of zinc acetate and 0.33 kg of lithium perchlorate, to the mixed solution B at once, and stir at room temperature for 30 minutes to obtain a clear and transparent electrolyte. Add an appropriate amount of lithium hydroxide or acetic acid to the clear and transparent electrolyte, and fine-tune the pH to 7.0.

[0084] The electrode of Comparative Example 1 can optionally use the electrode of Example 4, or use the electrode of Example 4 without the polyallyl nickel sulfonate nanopowder.

[0085] Comparative Example 2

[0086] As another comparative example, this comparative example 2 illustrates a dilute electrolyte for a mixed electrochemical system of aqueous zinc and lithium, which has no bulk ion migration controller E1 and interface ion migration controller E2 and contains only an ionizable electrochemically active component E3:

[0087] Step 1: Add ionizable electrochemically active component E3, namely, 0.8 kg of zinc acetate and 0.33 kg of lithium perchlorate, into 3.6 kg of pure water solvent at one time, and stir at room temperature for 30 minutes to obtain a clear and transparent electrolyte.

[0088] Step 2: Add an appropriate amount of lithium hydroxide or acetic acid to the above clear and transparent electrolyte and fine-tune the pH to 7.0.

[0089] The electrode of Comparative Example 2 can optionally use the electrode of Example 4, or use the electrode of Example 4 without the polyallyl nickel sulfonate nanopowder.

[0090] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

Claims

1. An electrochemical system for bulk and interface integrated ion migration control, characterized in that: include: Electrode, water-based electrolyte E and solid-phase ion guide R; water-based electrolyte E includes water solvent ES, bulk ion migration controller E1, interface ion migration controller E2 and ionizable electrochemical active component E3; The solid-phase ion guide R is dispersed in the positive electrode and the negative electrode, and the interface products for ion rectification and solvation regulation generated by the interface ion migration controller E2 are attached to the surfaces of the positive electrode and the negative electrode; The water-based electrolyte E is distributed between the interface products generated by the interface ion migration controller E2 on both sides, the bulk ion migration controller E1 forms a dynamic tunnel between the interface ion migration controller E2 on both sides, the water solvent ES and the ionizable electrochemically active component E3 are transported in the dynamic tunnel, and the ionizable electrochemically active component E3 is dispersed in the water solvent ES.

2. The electrochemical system for bulk and interface integrated ion migration control according to claim 1, characterized in that: The bulk ion migration controller E1 includes electrochemically active ions, auxiliary ions and non-ionized auxiliary solutes. The electrochemically active ions and auxiliary ions are ionophilic phases, and the non-ionized auxiliary solutes are ionophobic phases. The ionophobic phases are distributed on the dynamic tunnel walls, and the ionophilic phases are distributed in the dynamic tunnels.

3. The electrochemical system for bulk and interface integrated ion migration control according to claim 1, characterized in that: The solid phase ion conductor R accounts for 0.5 to 5 wt.% of the electrode mass. The metal cations in the solid phase ion conductor R include at least one of magnesium, calcium, manganese, iron, cobalt, nickel, copper, zinc, aluminum, indium, titanium and zirconium, and the anions include at least one of oxalate ions, polyalkyl sulfonate ions, polyalkyl carboxylate ions, phosphate ions, phosphonate ions and phosphonate derivative ions.

4. The electrochemical system for bulk and interface integrated ion migration control according to claim 1, characterized in that: The bulk ion migration controller E1 includes at least two of polyols, polyol hydrocarbon ethers, thiols, alcohol amines, carbonamides, hydrocarbon ureas, thioureas, hydrocarbon amides, cyanamides, glucose, fructose, sucrose, galactose and hydrocarbon phosphates, and the molar ratio of the bulk ion migration controller E1 to the water solvent ES is 1:10 to 5:

1.

5. The electrochemical system for bulk and interface integrated ion migration control according to claim 1, characterized in that: The interface ion migration controller E2 includes at least one of silicate, alkoxysilane, unsaturated hydrocarbon amide, polyol acrylate, imidazole, alkyl imidazole and aromatic carboxylic acid, and the molar ratio of the interface ion migration controller E2 to the water solvent ES is 1:10 to 1:

2.

6. The electrochemical system for bulk and interface integrated ion migration control according to claim 1, characterized in that: The ionizable electrochemically active component E3 includes at least one of soluble salts of lithium, sodium, potassium, zinc and ammonium cations, the anions of the ionizable electrochemically active component E3 include at least one of sulfate ion, formate ion, acetate ion, perchlorate ion, sulfonate ion, sulfonic acid derivative ion, sulfonyl imide ion and sulfonyl imide derivative ion, and the molar ratio of the ionizable electrochemically active component E3 to the aqueous solvent ES is 1:10 to 1:

1.

7. The method for preparing the electrochemical system for controlling ion migration with integrated bulk and interface as claimed in any one of claims 1 to 6, characterized in that: The following steps are involved: Step 1, adding bulk ion migration controller E1 to water solvent ES, stirring to obtain mixed solution A; Step 2: Add the interfacial ion migration controller E2 to the mixed solution A and stir to obtain a mixed solution B; Step 3, adding the ionizable electrochemically active component E3 to the mixed solution B, stirring to obtain a water-based electrolyte E, and adjusting the pH of the water-based electrolyte E to 6.0-9.0; Step 4: adding a solid phase ion conductor R to the positive electrode slurry and the negative electrode slurry to prepare an electrode material; Step 5: Assemble the water-based electrolyte E and the electrode materials to form an aqueous electrochemical energy storage device, thereby obtaining an electrochemical system with integrated bulk and interface ion migration control.

8. The method for preparing the electrochemical system for bulk and interface integrated ion migration control according to claim 7, characterized in that: In step 1 to step 3, the water-based electrolyte E is prepared at 40-80°C.

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