Aqueous battery and manufacturing method thereof

Abstract

The invention discloses an aqueous battery and a manufacturing method thereof, and relates to the technical field of batteries, the aqueous battery comprises an electrode pair, a mesh diaphragm and a polyanion electrolyte layer; the electrode pair comprises a positive electrode and a negative electrode; the net-shaped diaphragm is arranged between the positive electrode and the negative electrode; the polyanion electrolyte layer is distributed on the reticular diaphragm; the polyanion electrolyte layer comprises a polyanion polymer, monovalent positive ion salt and multivalent positive ion salt, and the polyanion polymer comprises macromolecules of at least one of carboxyl, sulfonic acid group and phosphonic acid group. According to the scheme, through the combined action of the polyanionic polymer, the monovalent positive ion salt and the multivalent positive ion salt, corresponding ions released from the negative electrode can be limited to move towards the positive electrode in the charging and discharging process, and spinel without electrochemical activity is prevented from being generated on the positive electrode side; therefore, the structural change of the positive electrode material in the charging and discharging process can be slowed down on the premise that the process manufacturing difficulty is not increased and the cost is prevented from being too high, and the service life of the battery is prolonged.

Description

Technical Field

[0001] The present invention relates to the technical field of batteries, and in particular to an aqueous battery and a manufacturing method thereof. Background Art

[0002] Aqueous batteries, due to their unique safety and ease of production, hold broad application prospects in flexible wearable electronics, medical devices, and low-power IoT applications. Compared to lithium-ion batteries, aqueous batteries fundamentally reduce safety risks during production, and their simpler and more cost-effective manufacturing process make them a highly promising energy storage technology.

[0003] However, in traditional aqueous battery technology, there is a problem that needs to be solved urgently: the structural stability of the positive electrode material is insufficient during the battery's recycling process; specifically, the positive electrode material is prone to structural changes during the charge and discharge process, resulting in the inability of ions to smoothly insert into the positive electrode material, thereby causing the battery's cycle performance to deteriorate. In existing research, methods such as coating a solid electrolyte interphase (SEI) membrane on the electrode surface or using an ion exchange membrane are usually used to solve the above problem. Although these methods can improve battery performance to a certain extent, they have disadvantages such as complex manufacturing processes and high costs, which limit the large-scale application of aqueous batteries. Summary of the Invention

[0004] The main purpose of the present invention is to propose an aqueous battery that can slow down the structural changes of the positive electrode material during the battery cycle without increasing the difficulty of process manufacturing and avoiding excessively high costs, thereby avoiding the problem of decreased battery cycle performance due to the inability of ions to smoothly insert into the positive electrode material.

[0005] To achieve the above objectives, the aqueous battery proposed by the present invention comprises:

[0006] an electrode pair, the electrode pair comprising a positive electrode and a negative electrode;

[0007] a mesh separator disposed between the positive electrode and the negative electrode;

[0008] The polyanion electrolyte layer is distributed on the mesh diaphragm; the polyanion electrolyte layer includes a polyanion polymer, a monovalent positive ion salt and a multivalent positive ion salt, and the polyanion polymer includes a macromolecule of at least one of a carboxyl group, a sulfonic acid group and a phosphonic acid group.

[0009] In one embodiment, the positive electrode is configured as a manganese dioxide electrode, the negative electrode is configured as a zinc electrode, and the multivalent positive ion salt includes a first positive ion, the size of the first positive ion is larger than the size of the zinc ion, and the first positive ion cannot be inserted into the manganese dioxide lattice of the positive electrode.

[0010] In one embodiment, the positive electrode and the negative electrode are configured as current collector electrodes, the multivalent positive ion salt includes a zinc salt and a manganese salt, and the monovalent positive ion salt includes a second positive ion, the size of the second positive ion is larger than the size of the zinc ion, and the second positive ion cannot be inserted into the manganese dioxide lattice of the positive electrode.

[0011] In one embodiment, the polyanionic electrolyte layer comprises mediator ions, and the polyanionic polymer is used to suppress the shuttling reaction of the mediator ions between the positive electrode and the negative electrode.

[0012] In one embodiment, the mediator ions include iron ions, the negative electrode does not contain the target metal element, and the standard electrode potential of the half-reaction of the target metal element in a neutral solution is greater than the standard electrode potential of the half-reaction of iron in a neutral solution.

[0013] In one embodiment, the current collector electrode comprises activated carbon, and at least part of the capacitance of the aqueous battery is provided by the supercapacitor function of the activated carbon.

[0014] Correspondingly, the present invention also provides a method for manufacturing an aqueous battery, which is used to manufacture the aqueous battery as described above, and the method for manufacturing the aqueous battery comprises the following steps:

[0015] Pre-adding the monovalent positive ion salt and / or the multivalent positive ion salt to the electrode pair;

[0016] In the case where the monovalent positive ion salt is pre-added to the electrode pair, the aqueous solution of the polyanionic polymer and the concentrated solution of the multivalent positive ion salt are sequentially added to the electrode pair;

[0017] In the case where the multivalent positive ion salt is pre-added to the electrode pair, a concentrated solution of the monovalent positive ion salt and an aqueous solution of the polyanion polymer are sequentially added to the electrode pair, or a polyanion solution is added to the electrode pair; the polyanion solution is formed by mixing the polyanion polymer with the monovalent positive ion salt;

[0018] In the case where the monovalent positive ion salt and the multivalent positive ion salt are added to the electrode pair in advance, the aqueous solution of the polyanionic polymer is added to the electrode pair.

[0019] Correspondingly, the present invention also provides a method for manufacturing an aqueous battery, which is used to manufacture the aqueous battery as described above, and the method for manufacturing the aqueous battery comprises the following steps:

[0020] Adding a polyanion solution or an aqueous solution of the polyanion polymer to the electrode pair; the polyanion solution is formed by mixing the polyanion polymer with the monovalent positive ion salt;

[0021] In the case where the polyanion solution is added to the electrode pair, a concentrated solution of the multivalent cation salt is added to the electrode pair;

[0022] In the case where the aqueous solution of the polyanionic polymer is added to the electrode pair, the concentrated solution of the monovalent positive ion salt and the concentrated solution of the multivalent positive ion salt are sequentially added to the electrode pair.

[0023] In one embodiment, the polyanion solution is prepared by any of the following methods:

[0024] adding a polyanionic polymer to the solution of the monovalent positive ion salt to form the polyanionic solution;

[0025] dissolving the monovalent positive ion salt in the aqueous solution of the polyanionic polymer to form the polyanionic solution;

[0026] The concentrated solution of the monovalent cationic salt is mixed with the aqueous solution of the polyanionic polymer to form the polyanionic solution.

[0027] In one embodiment, when the concentrated solution of the monovalent positive ion salt is added to the electrode pair, the monovalent positive ion salt comprises a single molecule of an organic acid.

[0028] The aqueous battery proposed by the present invention effectively restricts the movement of the corresponding ions released from the negative electrode to the positive electrode during the charge and discharge process through the combined action of the polyanion polymer, monovalent cationic salt and multivalent cationic salt in the polyanionic electrolyte layer, and to a certain extent inhibits the formation of spinel with no electrochemical activity on the positive electrode side. This can slow down the structural changes of the positive electrode material during the charge and discharge process without increasing the difficulty of process manufacturing and avoiding excessive costs, avoiding the problem of battery cycle performance degradation caused by the inability of other ions to smoothly insert into the positive electrode, and extending the battery life; and generates a quasi-solid gel through in-situ ionic polymerization; wherein, by pre-adding monovalent cationic salt, the overall performance of the battery is improved without changing the in-situ ionic polymerization process. In addition, the present invention also utilizes the charge repulsion of the polyanion to reduce the shuttle reaction of the mediating ion; and utilizes the high specific surface area of ​​activated carbon (Specific Surface Area), not only optimizing the electrode plating site, but also adding the supercapacitor capacity to the battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying any creative work.

[0030] Figure 1 A schematic diagram of experimental results of the first embodiment of the aqueous battery provided by the present invention;

[0031] Figure 2 A schematic diagram of experimental results of the second embodiment of the aqueous battery provided by the present invention;

[0032] Figure 3 A schematic diagram of experimental results of the third embodiment of the aqueous battery provided by the present invention;

[0033] Figure 4 A schematic diagram of the first experimental results of the fourth embodiment of the aqueous battery provided by the present invention;

[0034] Figure 5 A schematic diagram of the second experimental results of the fourth embodiment of the aqueous battery provided by the present invention;

[0035] Figure 6 A schematic diagram of the third experimental results of the fourth embodiment of the aqueous battery provided by the present invention;

[0036] Figure 7 A schematic diagram of experimental results of the fifth embodiment of the aqueous battery provided by the present invention;

[0037] Figure 8 A schematic diagram of the first experimental results of the sixth embodiment of the aqueous battery provided by the present invention;

[0038] Figure 9 A schematic diagram of the second experimental results of the sixth embodiment of the aqueous battery provided by the present invention;

[0039] Figure 10 A schematic diagram of the first experimental results of the seventh embodiment of the aqueous battery provided by the present invention;

[0040] Figure 11 A schematic diagram of the second experimental results of the seventh embodiment of the aqueous battery provided by the present invention;

[0041] Figure 12 A schematic diagram of the first experimental results of the eighth embodiment of the aqueous battery provided by the present invention;

[0042] Figure 13 A schematic diagram of the second experimental results of the eighth embodiment of the aqueous battery provided by the present invention;

[0043] Figure 14 This is a graph showing the experimental results of a comparative experiment on liquid gelation of sodium alginate according to the present invention;

[0044] Figure 15 This is a graph showing the experimental results of a comparative experiment on liquid gelation of iota-carrageenan according to the present invention;

[0045] Figure 16 A schematic flow chart of a first embodiment of a method for manufacturing an aqueous battery provided by the present invention;

[0046] Figure 17 A schematic flow chart of a second embodiment of the method for manufacturing an aqueous battery provided by the present invention;

[0047] Figure 18 This is a schematic diagram of experimental results of the third embodiment of the method for manufacturing an aqueous battery provided by the present invention.

[0048] The purpose, features and advantages of the present invention will be further described with reference to the accompanying drawings and in conjunction with the embodiments. DETAILED DESCRIPTION

[0049] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts shall fall within the scope of protection of the present invention.

[0050] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture. If the specific posture changes, the directional indications will also change accordingly.

[0051] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only for descriptive purposes and cannot be understood as indicating or suggesting their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features limited to "first" and "second" may explicitly or implicitly include at least one of such features. In addition, if "and / or" or "and / or" appears in the full text, its meaning includes three parallel solutions. Taking "A and / or B" as an example, it includes solution A, solution B, or solutions that satisfy both A and B. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in this field to implement. When the combination of technical solutions is mutually contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0052] Aqueous batteries, due to their unique safety and ease of production, hold broad application prospects in flexible wearable electronics, medical devices, and low-power IoT applications. Compared to lithium-ion batteries, aqueous batteries fundamentally reduce safety risks during production, and their simpler and more cost-effective manufacturing process make them a highly promising energy storage technology.

[0053] However, in traditional aqueous battery technology, there is a problem that needs to be solved urgently: the structural stability of the positive electrode material is insufficient during the battery's recycling process; specifically, the positive electrode material is prone to structural changes during the charge and discharge process, resulting in the inability of ions to smoothly insert into the positive electrode material, thereby causing the battery's cycle performance to deteriorate. In existing research, methods such as coating a solid electrolyte interphase (SEI) membrane on the electrode surface or using an ion exchange membrane are usually used to solve the above problem. Although these methods can improve battery performance to a certain extent, they have disadvantages such as complex manufacturing processes and high costs, which limit the large-scale application of aqueous batteries.

[0054] In order to solve the above problems, the present invention provides an aqueous battery that can slow down the structural changes of the positive electrode material during the battery cycle without increasing the difficulty of process manufacturing and avoiding excessively high costs, thereby avoiding the problem of decreased battery cycle performance due to the inability of ions to smoothly insert into the positive electrode material.

[0055] See also Figure 1 and Figure 2 The aqueous battery provided by the present invention comprises:

[0056] an electrode pair, the electrode pair comprising a positive electrode and a negative electrode;

[0057] a mesh separator disposed between the positive electrode and the negative electrode;

[0058] The polyanion electrolyte layer is distributed on the mesh diaphragm; the polyanion electrolyte layer includes polyanion polymer, monovalent positive ion salt and multivalent positive ion salt, and the polyanion polymer includes macromolecules of at least one of carboxyl group, sulfonic acid group and phosphonic acid group.

[0059] The core of this embodiment is to significantly improve the cycle performance and stability of aqueous batteries through special electrolyte design and electrode configuration. Specifically, the positive electrode can use manganese dioxide (MnO2) as the active material. Manganese dioxide has good electrochemical properties and stability, such as the most common crystalline phase EMD (commercial electrolytic manganese dioxide); during the preparation process, manganese dioxide powder can be mixed with an appropriate amount of conductive agent (such as carbon black) and a binder (such as polyvinylidene fluoride, PVDF) to form a slurry, which is then coated on the current collector and dried to form a positive electrode. The negative electrode usually uses zinc (Zn) as the active material. Zinc has a high theoretical specific capacity and good electrochemical properties; during the preparation process, zinc powder can be mixed with an appropriate amount of conductive agent and a binder to form a slurry, which is then coated on the current collector and dried to form a negative electrode.

[0060] The mesh diaphragm is arranged between the positive electrode and the negative electrode to isolate the electrodes and prevent short circuits while allowing ions to pass through. The polyanion electrolyte layer is evenly distributed on the mesh diaphragm. The polyanion electrolyte layer contains polyanion polymers, monovalent positive ion salts, and multivalent positive ion salts. The polyanion polymers contain macromolecules containing at least one of carboxyl groups, sulfonic acid groups, and phosphonic acid groups. These functional groups give the polyanion polymers good ion conductivity and chemical stability. Monovalent positive ion salts can be NH2Cl, NH4Ac, KCl, NaCl, etc., to provide monovalent positive ions. Multivalent positive ion salts can be MgCl2, CaCl2, FeCl2, ZnCl2, etc., to provide multivalent positive ions. SO4 2- Can be used to replace Cl - The monovalent positive ion salts and multivalent positive ion salts can dissociate into corresponding ions in the electrolyte to provide ion carriers for the charge and discharge reactions of the battery.

[0061] Specifically, polyanionic polymers can be polyacrylic acid salts, alginates, carboxymethyl polymers, iota-carrageenan, sulfonated polymers, fucoidan, polypropylene sulfonates (such as poly-2-acrylamide-2-methylpropane sulfonic acid), polystyrene sulfonates, and polyvinylphosphonic acid. These polymers have good film-forming properties and ion conductivity, and can form a uniform gel layer in the electrolyte. This property is mainly due to their chemical structure. Taking sodium alginate and iota-carrageenan as examples, sodium alginate and iota-carrageenan are both natural polysaccharide polymers, and their molecular chains contain a large number of negatively charged groups such as carboxyl (-COOH) and sulfonic acid (-SO2H). These negatively charged groups enable the polymer chains to fully extend in aqueous solution, thereby forming a stable hydration layer. When these polymer solutions are under appropriate conditions (such as the addition of multivalent cations), the negatively charged groups react with multivalent cations (such as CaCl2) to form a hydrated layer. 2+ Mg 2+ ) cross-linking reaction to form a three-dimensional network structure, thereby achieving film formation. For example, sodium alginate reacts with Ca 2+ When cross-linked, a tough gel film is formed with good mechanical properties and stability. This film can evenly cover the mesh separator, isolating the electrodes and supporting the electrolyte.

[0062] The ionic conductivity of polyanionic polymers primarily comes from monovalent positive ions and discrete anions, as well as hydrogen ions from the hydrolysis of water molecules. Polyanions hinder the migration of some discrete anions through charge repulsion, while simultaneously inhibiting the migration of multivalent ions by clamping them.

[0063] In the preparation process of the polyanion electrolyte layer, taking a manganese dioxide electrode as the positive electrode and a zinc electrode as the negative electrode as an example, sodium alginate or iota carrageenan can be first dissolved in deionized water and stirred evenly to form a sodium alginate aqueous solution or an iota carrageenan aqueous solution with a concentration of 2 wt%; then, an NH2Cl solution with a concentration of 6.5 mol / L is added to the sodium alginate aqueous solution or the iota carrageenan aqueous solution, and the stirring is continued to form an NH2Cl solution of sodium alginate or an NH2Cl solution of iota carrageenan, and the NH2Cl of sodium alginate is added to the iota carrageenan aqueous solution. A 2Cl solution or an NH2Cl solution of iota-carrageenan is added between the positive electrode and the negative electrode, wherein the ratio of the sodium alginate aqueous solution (or the iota-carrageenan aqueous solution) to the NH2Cl solution can be 1:1; finally, a 6 mol / L MgCl2 solution or a 7.65 mol / L CaCl2 solution is added between the positive electrode and the negative electrode to fuse with the NH2Cl solution of sodium alginate or the NH2Cl solution of iota-carrageenan to form a gel layer that is evenly distributed on the mesh diaphragm, thereby ultimately forming a polyanion electrolyte layer.

[0064] Based on the above scheme, polyanionic polymers (such as sodium alginate or ι-carrageenan), monovalent cationic salts (such as NH2Cl) and multivalent cationic salts (such as MgCl2 or CaCl2) work together to form a complex ion network that can effectively limit the zinc ion (Zn 2+ ) movement. Specifically, the polyanionic polymer contains a large number of negatively charged groups, such as carboxyl groups, sulfonic acid groups, etc. These negatively charged groups will form an electrostatic field in the electrolyte, which will produce an electrostatic repulsion effect on the positively charged zinc ions; when the zinc ions are released from the negative electrode and enter the electrolyte, the negatively charged groups of the polyanionic polymer will interact with the zinc ions, hindering the zinc ions from moving to the positive electrode. At the same time, the multivalent positive ion salt dissociates into multivalent positive ions (such as Mg 2+ or Ca 2+ ), these multivalent positive ions interact with the negatively charged groups of the polyanionic polymer to form a network structure that can block the diffusing zinc ions, and this network structure further enhances the restriction effect on the movement of zinc ions.

[0065] The above synergistic effect effectively inhibits the movement of zinc ions, so that zinc ions are confined to the negative electrode side in the electrolyte and difficult to move to the positive electrode. This not only reduces the insertion of zinc ions on the positive electrode side, thereby inhibiting the formation of spinel (such as ZnMnO2) on the positive electrode side, but also maintains the structural stability of the positive electrode material (such as MnO2), thereby significantly improving the cycle performance and service life of the battery. At the same time, it avoids the problem of rapid battery capacity decay caused by changes in the positive electrode structure, thereby significantly improving the cycle performance and service life of the battery.

[0066] In addition, aqueous batteries generate H under water thermodynamic equilibrium. + , H + It is the main ion inserted into MnO2. The addition of MgCl2 and CaCl2 also reduces the pH value of the electrolyte, which can promote the + Inserted into MnO2, the charge and discharge performance of the battery can be further optimized.

[0067] After the aqueous battery is prepared, it can be placed in a constant current charge and discharge instrument for charge and discharge testing. The charge and discharge current can be set to 2mA, the charge capacity to 3-4mAh, and the discharge to 0V to test the battery's cycle performance and capacity retention rate. Through multiple charge and discharge cycle tests, the cycle stability of the aqueous battery can be evaluated. Figure 1 and Figure 2 The experimental results are as follows:

[0068] Figure 1:The positive electrode uses a preset manganese dioxide electrode, and the negative electrode uses a preset zinc electrode; under this premise, three cases are analyzed, namely, adding only CaCl2 between the positive and negative electrodes without adding other polyanionic polymers, adding CaCl2 and sodium alginate between the positive and negative electrodes, and adding CaCl2 and ι-carrageenan between the positive and negative electrodes. The experimental results are characterized by a table showing the relationship between the number of battery cycles and the discharge capacity; the charge and discharge current set in the experiment is 2mA, the charge capacity is 3-4mAh, and the discharge is to 0V;

[0069] Figure 2 : The positive electrode uses a preset manganese dioxide electrode, and the negative electrode uses a preset zinc electrode; under this premise, three situations are analyzed respectively, namely, adding only MgCl2 between the positive electrode and the negative electrode without adding other polyanion polymers, adding MgCl2 and sodium alginate between the positive electrode and the negative electrode, and adding MgCl2 and ι-carrageenan between the positive electrode and the negative electrode, and the experimental results are characterized by a table of changes in the relationship between the number of battery cycles and the discharge capacity; the charge and discharge current set in the experiment is 2mA, the charge capacity is 3~4mAh, and the discharge is to 0V.

[0070] The above experimental results show that through the combined action of polyanionic polymers, monovalent cationic salts and multivalent cationic salts, the cycle performance of aqueous batteries can be significantly improved and the capacity retention rate can be significantly improved.

[0071] In the verification experiment of this invention, to test the battery's discharge performance and capacity stability, the battery is first fully discharged to 0V using an electrolyte containing NH2Cl to completely deplete the battery capacity. The purpose is to verify the battery's performance under extreme discharge conditions and the stability of the electrode materials and electrolyte in a fully discharged state. This verification experiment ensures that the battery has reliable depth of discharge and cycling performance in practical applications.

[0072] It can be seen that the aqueous battery provided in this embodiment effectively limits the movement of corresponding ions released from the negative electrode to the positive electrode during the charge and discharge process through the combined action of the polyanion polymer, monovalent cationic salt and multivalent cationic salt in the polyanionic electrolyte layer, and inhibits the generation of electrochemically inactive spinel on the positive electrode side to a certain extent, thereby slowing down the structural changes of the positive electrode material during the charge and discharge process without increasing the difficulty of process manufacturing and avoiding excessive costs, avoiding the problem of decreased battery cycle performance due to the inability of other ions to smoothly insert into the positive electrode, and extending the service life of the battery; and generating a quasi-solid gel through in situ ionic polymerization; wherein, by pre-adding monovalent cationic salt, the comprehensive performance of the battery is improved without changing the in situ ionic polymerization process.

[0073] In one embodiment, reference Figure 1 and Figure 2 The positive electrode is set as a manganese dioxide electrode, the negative electrode is set as a zinc electrode, the multivalent positive ion salt includes a first positive ion, the size of the first positive ion is larger than the size of the zinc ion, and the first positive ion cannot be inserted into the manganese dioxide lattice of the positive electrode.

[0074] In this embodiment, the positive electrode is a pre-set manganese dioxide, and the negative electrode is a pre-set zinc. The multivalent positive ion salt can be made by mixing a variety of salts. Here, the multivalent positive ion salt is MgCl2 or CaCl2 as an example for explanation. The first positive ions separated are Mg 2+ and Ca 2+ , Mg 2+ and Ca 2+ The size of the zinc ions is larger than that of the zinc ions and cannot be inserted into the manganese dioxide lattice of the positive electrode.

[0075] During the charge and discharge process of aqueous batteries, zinc ions (Zn 2+ ) will be released from the negative electrode and move to the positive electrode and may be inserted into the lattice of the positive electrode material. However, when there are Mg 2+ , Ca 2+ When the first positive ions are of equal and large ion sizes, these first positive ions cannot be inserted into the lattice structure of manganese dioxide due to their large ion size; on the contrary, these first positive ions will compete with zinc ions in the electrolyte to compete for adsorption sites or ion transport channels on the surface of the positive electrode. This competition makes it more difficult for zinc ions to reach and insert into the manganese dioxide lattice of the positive electrode, thereby reducing the amount of zinc ions inserted on the positive electrode side, and further inhibiting the formation of electrochemically inactive substances such as spinel (such as ZnMnO2). Based on this scheme, the presence of the first positive ions helps to maintain the structural stability of the positive electrode material and improve the cycle performance and service life of the battery.

[0076] In one embodiment, reference Figure 3 The positive electrode and the negative electrode are set as current collector electrodes, the multivalent positive ion salt includes a zinc salt and a manganese salt, and the monovalent positive ion salt includes a second positive ion, the size of the second positive ion is larger than the size of the zinc ion, and the second positive ion cannot be inserted into the manganese dioxide lattice of the positive electrode.

[0077] In this embodiment, a current collector electrode is selected as the basic structure during the preparation of the positive and negative electrodes. The current collector electrode is typically made of a material with good electrical conductivity, such as a carbon electrode. The advantage of this design is that it allows zinc and manganese oxide to be deposited on the corresponding electrodes by electroplating during the initial charge and discharge process, thereby forming the active electrode material by electroplating; preferably, the zinc salt is added to the negative electrode and the manganese salt is added to the positive electrode. This electroplating method not only simplifies the electrode preparation process but also improves the overall performance of the battery.

[0078] The zinc salt in the multivalent positive ion salt can be specifically ZnAc2, and the manganese salt in the multivalent positive ion salt can be specifically MnAc2. These salts can deposit manganese dioxide and zinc on the positive electrode and the negative electrode respectively during the first charge and discharge process. The monovalent positive ion salt can be KCl, etc., which can release potassium ions (K + ) and other large ion sizes. The size of the second positive ion is larger than that of the zinc ion, so it cannot be inserted into the manganese dioxide lattice of the positive electrode, and mainly plays the role of ion conduction. In this way, this part of the second positive ion will also compete with the zinc ions in the electrolyte to compete for the adsorption sites or ion transport channels on the surface of the positive electrode. This competition makes it more difficult for zinc ions to reach and insert into the manganese dioxide lattice of the positive electrode, thereby reducing the amount of zinc ions inserted on the positive electrode side, and further suppressing the formation of non-electrochemically active substances such as spinel (such as ZnMnO2). That is, the presence of the second positive ion helps to maintain the structural stability of the positive electrode material, improve the cycle performance of the battery and extend its service life.

[0079] A specific preparation process of the polyanion electrolyte layer in this embodiment is as follows: 1M (mol / L) ZnAc2, 1M MnAc2, and 2M KCl salt powder are added to the positive electrode and negative electrode as the current collector electrode; at the same time, sodium alginate or iota carrageenan is dissolved in deionized water, stirred evenly to form a sodium alginate aqueous solution or iota carrageenan aqueous solution with a concentration of 2wt%, and added between the positive electrode and the negative electrode; in this way, a gel layer is formed and evenly distributed on the mesh separator, thereby finally forming a polyanion electrolyte layer. Among them, chloride ions (Cl - ) can be used to increase the solubility of acetate (Ac), while acetate helps to improve the electroplating efficiency of manganese dioxide at the positive electrode.

[0080] By adding the above-mentioned polyanionic polymers such as sodium alginate and ι-carrageenan, the zinc ions released by the negative electrode can be restricted from being inserted into the manganese dioxide lattice generated by electroplating in the positive electrode during the charge and discharge process, and the potassium ions (K +) competes with zinc ions, which can limit zinc ions to the negative electrode side and, to a certain extent, inhibit the formation of spinel (such as ZnMnO2) on the positive electrode side that has no electrochemical activity, thereby slowing down the structural changes of the positive electrode material during the charge and discharge process, improving the cycle performance of the battery and extending its service life. It is understandable that potassium ions can be replaced by NH4 + 、Na + Other second positive ions of equal size larger than zinc ions; among them, NH4 + Can be provided by NH4Cl, NH4 + As a weak base ion, it can not only provide an acidic electrolyte environment, but also form zinc ammonium salt precipitation, such as Zn(NH3)2Cl2, which can further lock Zn 2+ ion.

[0081] After the aqueous battery is prepared according to the above process, it can be placed in a constant current charge and discharge instrument for charge and discharge testing. The charge and discharge current can be set to 2mA, the charge capacity to 1mAh, and the discharge to 0V to test the battery's cycle performance and capacity retention rate. Through multiple charge and discharge cycle tests, the cycle stability of the aqueous battery can be evaluated. Figure 3 The experimental results are as follows:

[0082] Both the positive electrode and the negative electrode use carbon electrodes as current collectors, and 1M (mol / L) ZnAc2 and 1M MnAc2 are added between the positive electrode and the negative electrode; under this premise, four cases are analyzed, namely, adding 2M KCl without adding other polyanion polymers, adding 2M KCl and adding sodium alginate, adding 2M KCl and adding ι-carrageenan, and adding 2M NH4Cl without adding other polyanion polymers, and the experimental results are characterized by a table of changes in the relationship between the number of battery cycles and the discharge capacity; the charge and discharge current set in the experiment is 2mA, the charge capacity is 1mAh, and the discharge is to 0V.

[0083] The experimental results show that through the interaction between polyanionic polymer, monovalent cationic salt and multivalent cationic salt, as well as K + NH4 + Due to the competitive effect of the second positive ions on zinc ions, the cycle performance of the aqueous battery can be significantly improved and the capacity retention rate is significantly improved.

[0084] In one embodiment, reference Figures 4 to 7 The polyanionic electrolyte layer contains mediator ions, and the polyanionic polymer is used to inhibit the shuttle reaction of the mediator ions between the positive electrode and the negative electrode.

[0085] Specifically, the mediator ions may include iodide ions, iron ions, chromium ions, etc. The beneficial effect of adding mediator ions is that the mediator ions can provide additional charge transfer paths during the charge and discharge process of the battery, thereby improving the electrochemical performance of the battery. However, taking the mediator ions including iodide ions as an example, iodide ions can be oxidized to I3 by MnO2 on the positive electrode side. - (i.e. I2+I - ), then I3 - The zinc that diffuses to the negative electrode side is reduced. This reaction is called the shuttle reaction. If this shuttle reaction is not controlled, it may lead to battery self-discharge and capacity attenuation problems.

[0086] Based on the above problems, this embodiment uses polyanionic polymers such as sodium alginate and iodine-carrageenan to effectively control the shuttle reaction of iodide ions, thereby increasing the storage capacity of the battery after storage and improving the coulombic efficiency.

[0087] Taking the positive electrode as a current collector electrode (such as a carbon electrode) and the negative electrode as a preset zinc electrode as an example, a specific preparation process of the polyanion electrolyte layer in this embodiment is as follows: 1M (mol / L) ZnAc2, 1M MnAc2, and 2M KCl salt powders are added to the positive electrode serving as the current collector electrode; at the same time, sodium alginate or iota-carrageenan is dissolved in deionized water and stirred evenly to form a sodium alginate aqueous solution or iota-carrageenan aqueous solution with a concentration of 2wt%, which is then added between the positive electrode and the negative electrode; and a concentrated solution of 0.1M KI corresponding to a volume is added between the positive electrode and the negative electrode to merge with the sodium alginate aqueous solution or the iota-carrageenan aqueous solution; in this way, a gel layer is formed and evenly distributed on the mesh diaphragm, thereby ultimately forming a polyanion electrolyte layer.

[0088] Among them, the positive electrode and the negative electrode are not limited to the above-mentioned forms. The positive electrode can adopt a pre-set manganese dioxide electrode or a current collector electrode formed by electroplating an active electrode material as needed. The negative electrode can adopt a pre-set zinc electrode or a current collector electrode formed by electroplating an active electrode material as needed. The current collector electrode can adopt a carbon electrode, an activated carbon electrode, etc., which is not limited here.

[0089] After the aqueous battery is prepared according to the above process, it can be placed in a constant current charge and discharge instrument for charge and discharge testing. Through multiple charge and discharge cycle tests, the cycle stability of the aqueous battery can be evaluated. Figures 4 to 7 The experimental results characterized are as follows:

[0090] Figure 4:The positive electrode uses a carbon electrode as a current collector, the negative electrode uses a preset zinc electrode, and 1M (mol / L) ZnAc2, 1M MnAc2, 2M KCl and 0.1M KI are added between the positive and negative electrodes; under this premise, three cases are analyzed respectively, including no addition of other polyanionic polymers, addition of sodium alginate, and addition of ι-carrageenan, and the capacity after standing still is characterized by the relationship between the discharge time and voltage after standing still for 3 hours; the charge and discharge current set in this experiment is 2mA, the charge capacity is 1mAh, and the discharge is to 0V;

[0091] Figure 5 :The positive electrode uses a carbon electrode as a current collector, the negative electrode uses a preset zinc electrode, and 1M (mol / L) ZnAc2, 1M MnAc2, 2M KCl and 0.1M KI are added between the positive and negative electrodes; under this premise, three cases are analyzed respectively: no other polyanionic polymers are added, sodium alginate is added, and ι-carrageenan is added, and the experimental results are characterized by the efficiency loss of the battery after standing for 3 hours (that is, the capacity loss ratio compared with no standing); the charge and discharge current set in this experiment is 2mA, the charge capacity is 1mAh, and the discharge is to 0V;

[0092] Figure 6 :The positive electrode uses a carbon electrode as a current collector, the negative electrode uses a preset zinc electrode, and 1M (mol / L) ZnAc2, 1M MnAc2, 2M KCl and 0.1M KI are added between the positive and negative electrodes; under this premise, three cases are analyzed respectively for no addition of other polyanion polymers, addition of sodium alginate, and addition of ι-carrageenan, and the experimental results are characterized by the relationship table between the number of battery cycles and discharge capacity. It can be seen that after the addition of polyanions, the coulombic efficiency and cycle performance are improved; the charge and discharge current set in this experiment is 2mA, the charge capacity is 1mAh, and the discharge is to 0V;

[0093] Figure 7 : The positive electrode uses an activated carbon (AC) electrode as a current collector, and the negative electrode uses a preset zinc electrode. 1M (mol / L) ZnAc2, 1M MnAc2, 2M KCl and 0.1M KI are added between the positive electrode and the negative electrode; under this premise, two cases are analyzed respectively for no addition of other polyanion polymers and addition of sodium alginate, and the experimental results are characterized by the relationship table between the number of battery cycles and the discharge capacity. It can be seen that after the addition of polyanions, the cycle performance is improved; the charge and discharge current set in the experiment is 2mA, the charging capacity is 3mAh, and the discharge is to 0V.

[0094] The above experimental results show that polyanionic polymers such as sodium alginate and ι-carrageenan can effectively control the shuttle reaction of iodide ions, thereby increasing the storage capacity of the battery after storage and improving the coulombic efficiency.

[0095] In one embodiment, reference Figures 8 to 13 , the mediator ions include iron ions, the negative electrode does not contain the target metal element, and the standard electrode potential of the half reaction of the target metal element in a neutral solution is greater than the standard electrode potential of the half reaction of iron in a neutral solution.

[0096] The mediator ions in this embodiment specifically include Fe 2+ 、Fe 3+ Iron ions can provide additional charge transfer pathways during the battery's charge and discharge processes, and iron's good acid resistance can improve the battery's Coulombic efficiency, thereby enhancing the battery's overall electrochemical performance. Adding polyanionic polymers such as sodium alginate and iota-carrageenan can effectively control the shuttling reaction of iron ions, increase the concentration of iron ions allowed in the solution, and thus improve the battery's storage capacity after storage and further enhance its Coulombic efficiency.

[0097] However, when the negative electrode is set as a zinc electrode, when the above-mentioned multivalent iron ions shuttle between the positive electrode and the negative electrode, the iron ions will react with the metallic zinc to generate metallic iron. The metallic iron reacts with the ferric ions to generate divalent iron ions, which are then oxidized to ferric ions by the positive electrode. In this way, the concentration of iron ions in the electrolyte will gradually increase and gradually exceed the diffusion limit of the polyanion gel. Therefore, the present invention aims to fix the iron ions in the form of metallic iron at the negative electrode, so that a low iron ion concentration is maintained in the solution, thereby obtaining a stable iron battery.

[0098] Based on the above ideas, in this embodiment, when iron ions are selected as the mediator ions, the activity of the metal element in the negative electrode is limited to be less than the activity of iron (that is, the standard electrode potential of the half-reaction of the metal element in the negative electrode in a neutral solution is greater than the standard electrode potential of the half-reaction of iron in a neutral solution). In this way, the iron ions can be fixed at the negative electrode in the form of metallic iron, so that the iron ion concentration in the solution is maintained at a low level, thereby obtaining a stable iron battery.

[0099] In the case where the mediating ions include iron ions, after the aqueous battery is prepared according to the process in the above embodiment, the aqueous battery can be placed in a constant current charge and discharge instrument for charge and discharge testing. Through multiple charge and discharge cycle tests, the cycle stability of the aqueous battery can be evaluated. Figures 8 to 13 The experimental results characterized are as follows:

[0100] Figure 8:Both the positive electrode and the negative electrode use carbon electrodes as current collectors, and 2M (mol / L) ZnCl2, 2M MnCl2, and 0.1M FeCl3 are added between the positive electrode and the negative electrode; under this premise, three cases are analyzed respectively, including no addition of other polyanionic polymers, addition of sodium alginate, and addition of ι-carrageenan, and the experimental results are characterized by the relationship between the discharge time and voltage of the battery; the charge and discharge current set in this experiment is 2mA, the charge capacity is 0.2mAh, and the discharge is to 0V;

[0101] Figure 9 :Both the positive and negative electrodes used carbon electrodes as current collectors, and 2M (mol / L) ZnCl2, 2M MnCl2, and 0.1M FeCl3 were added between the positive and negative electrodes. Under this premise, three cases were analyzed, including no addition of other polyanionic polymers, addition of sodium alginate, and addition of ι-carrageenan, and the experimental results were characterized by the discharge capacity of the battery. The charge and discharge current set in this experiment was 2mA, the charge capacity was 0.2mAh, and the discharge was to 0V.

[0102] Figure 10 :Both the positive electrode and the negative electrode use carbon electrodes as current collectors, and 2M (mol / L) ZnCl2, 2M MnCl2, and 0.3M FeCl3 are added between the positive electrode and the negative electrode; under this premise, three cases are analyzed respectively, including no addition of other polyanionic polymers, addition of sodium alginate, and addition of ι-carrageenan, and the experimental results are characterized by the relationship between the discharge time and voltage of the battery; the charge and discharge current set in this experiment is 2mA, the charge capacity is 0.2mAh, and the discharge is to 0V;

[0103] Figure 11 :Both the positive and negative electrodes used carbon electrodes as current collectors, and 2M (mol / L) ZnCl2, 2M MnCl2, and 0.3M FeCl3 were added between the positive and negative electrodes. Under this premise, three cases were analyzed, including no addition of other polyanionic polymers, addition of sodium alginate, and addition of ι-carrageenan, and the experimental results were characterized by the discharge capacity of the battery. The charge and discharge current set in this experiment was 2mA, the charge capacity was 0.2mAh, and the discharge was to 0V.

[0104] Figure 12:Both the positive electrode and the negative electrode use carbon electrodes as current collectors, and 2M (mol / L) ZnCl2, 2M MnCl2, and 0.5M FeCl3 are added between the positive electrode and the negative electrode; under this premise, three cases are analyzed respectively for no addition of other polyanionic polymers, addition of sodium alginate, and addition of ι-carrageenan, and the experimental results are characterized by the relationship between the discharge time and voltage of the battery; the charge and discharge current set in this experiment is 2mA, the charge capacity is 0.2mAh, and the discharge is to 0V;

[0105] Figure 13 :Both the positive electrode and the negative electrode use carbon electrodes as current collectors, and 2M (mol / L) ZnCl2, 2M MnCl2, and 0.5M FeCl3 are added between the positive and negative electrodes. Under this premise, three cases are analyzed respectively: no addition of other polyanionic polymers, addition of sodium alginate, and addition of ι-carrageenan. The experimental results are characterized by the discharge capacity of the battery. The charge and discharge current set in this experiment is 2mA, the charge capacity is 0.2mAh, and the discharge is to 0V. Figure 13 It can be seen from the figure that without adding other polyanionic polymers, when Fe 3+ When the concentration of Fe exceeds a certain value, the battery can hardly discharge due to the shuttle effect; in the case of adding polyanionic polymers such as sodium alginate and ι-carrageenan, the restriction of polyanionic polymers can effectively reduce the discharge of Fe. 3+ When the concentration reaches the above value, the battery still retains some capacity.

[0106] The above experimental results show that when there are differences in the amount of iron ions added as the mediating ions, polyanionic polymers such as sodium alginate and ι-carrageenan can effectively control the shuttle reaction of iron ions, thereby increasing the storage capacity of the battery after placement and improving the coulombic efficiency.

[0107] In one embodiment, reference Figure 7 , the current collector electrode comprises activated carbon, and at least part of the capacitance of the aqueous battery is provided by the supercapacitor function of the activated carbon.

[0108] In this embodiment, when the positive electrode and the negative electrode are configured as current collector electrodes that form active electrode materials by electroplating, both the positive electrode and the negative electrode can be configured as activated carbon electrodes. When activated carbon is included in the electrode, the supercapacitor function of the activated carbon can provide a portion of the capacitance for the aqueous battery. Specifically, a supercapacitor is an energy storage device based on the double layer effect or the Faraday pseudocapacitance effect. The supercapacitor function of the activated carbon in this embodiment is based on its high specific surface area and porous structure. These characteristics enable the activated carbon to form a large number of charge storage sites on the electrode surface, which can increase the specific capacity and charge and discharge rate of the battery through the double layer effect. In addition, the higher specific surface area (Specific Surface Area) of the activated carbon provides sufficient sites for depositing the electrode, which can reduce the probability of peeling problems caused by excessively thick electrode plating.

[0109] When the current collector electrode comprises activated carbon, this embodiment can effectively suppress the formation of spinel that is not electrochemically active by adding polyanionic polymers such as sodium alginate and iota-carrageenan, while effectively controlling the shuttle reaction of the mediator ion.

[0110] Regarding the aqueous battery provided in the above embodiment, the researchers of this application found during the preparation process that when multivalent positive ions are added to the polyanionic polymer, cross points are formed, thereby causing the liquid to gel; while when monovalent positive ions are added to the polyanionic polymer, the fluidity of the resulting solution is not affected. For specific experimental results, please refer to Figure 14 and Figure 15 It can be seen that after adding ZnCl2 into the sodium alginate solution with a concentration of 1wt%, sodium alginate will react with divalent positive ions (Zn 2+ ) to form a gel; similarly, after adding ZnCl2 to a 1 wt% iota carrageenan solution, iota carrageenan will also react with divalent cations (Zn 2+ ) polymerizes to form a gel; on the contrary, when KCl, KAc, KOH, NH4Cl, NH4Ac, and NaCl are added to a 1 wt% sodium alginate solution (i.e., K + NH4 + 、Na + When monovalent positive ions are present), the obtained polyanion solution still maintains fluidity.

[0111] Based on the above findings, in order to avoid the inconvenience caused by solution gelation in the preparation process, the following specific preparation process is proposed:

[0112] See also Figure 16 The present invention provides a method for manufacturing an aqueous battery, which is used to manufacture the aqueous battery in any of the above embodiments. The method for manufacturing the aqueous battery includes the following steps:

[0113] Pre-adding monovalent positive ion salt and / or multivalent positive ion salt to the electrode pair;

[0114] In the case where a monovalent positive ion salt is pre-added to the electrode pair, an aqueous solution of a polyanionic polymer and a concentrated solution of a multivalent positive ion salt are sequentially added to the electrode pair;

[0115] In the case where a multivalent positive ion salt is pre-added to the electrode pair, a concentrated solution of a monovalent positive ion salt and an aqueous solution of a polyanion polymer are sequentially added to the electrode pair, or a polyanion solution is added to the electrode pair; the polyanion solution is formed by mixing the polyanion polymer with the monovalent positive ion salt;

[0116] In the case where a monovalent positive ion salt and a polyvalent positive ion salt are added to the electrode pair in advance, an aqueous solution of a polyanionic polymer is added to the electrode pair.

[0117] See also Figure 17 The present invention also provides a method for manufacturing an aqueous battery, which is used to manufacture the aqueous battery in any of the above embodiments. The method for manufacturing the aqueous battery includes the following steps:

[0118] Adding a polyanion solution or an aqueous solution of a polyanion polymer to the electrode pair; the polyanion solution is formed by mixing a polyanion polymer with a monovalent positive ion salt;

[0119] In the case where a polyanion solution is added to the electrode pair, a concentrated solution of a multivalent cation salt is added to the electrode pair;

[0120] In the case where an aqueous solution of a polyanionic polymer is added to the electrode pair, a concentrated solution of a monovalent positive ion salt and a concentrated solution of a multivalent positive ion salt are sequentially added to the electrode pair.

[0121] In one embodiment, reference Figure 17 , the polyanion solution is prepared by any of the following methods:

[0122] Adding a polyanionic polymer to a solution of a monovalent cationic salt to form a polyanionic solution;

[0123] dissolving a monovalent positive ion salt in an aqueous solution of a polyanionic polymer to form a polyanionic solution;

[0124] A concentrated solution of a monovalent cationic salt is mixed with an aqueous solution of a polyanionic polymer to form a polyanionic solution.

[0125] The above embodiments cover a variety of specific preparation processes, all of which share the commonality of first mixing monovalent positive ions with polyvalent positive ions, or first mixing monovalent positive ions with polyanionic polymers, and ensuring that the polyvalent positive ions and polyanionic polymers are mixed between the positive and negative electrodes in the final stage. This ensures that gelation, which occurs after the polyvalent positive ions and polyanionic polymers are mixed, occurs at the very end of the preparation process. This avoids the inconvenience caused by gelation before the preparation process is complete, maintaining solution fluidity and facilitating operations such as solution transfer and mixing. This is more in line with actual production practices, thereby ensuring production efficiency.

[0126] In one embodiment, reference Figures 16 to 18 , in the case where a concentrated solution of a monovalent positive ion salt is added to the electrode pair, the monovalent positive ion salt contains a single molecule of an organic acid.

[0127] In actual operation, taking the case where both the positive electrode and the negative electrode are current collector electrodes, ZnAc2, MnAc2 and KCl are usually added between the positive electrode and the negative electrode. However, the solubility of these three salts is relatively low, which may lead to insufficient electrode reaction, poor electrolyte conductivity, decreased cycle stability and other problems. To solve this problem, this embodiment stipulates that when a concentrated solution of a monovalent positive ion salt is added to the electrode pair, the monovalent positive ion salt should contain a single molecule of an organic acid; specifically, potassium acetate (KAc), ammonium acetate (NH4Ac) and the like can be used as the monovalent positive ion salt, which can improve the solubility; in addition, the above-mentioned ZnAc2 and MnAc2 can also be replaced by ZnCl2 and MnCl2 with higher solubility, which can avoid the tedious weighing steps and instead be prepared by the volume of the concentrated solution.

[0128] To verify the above conclusion, two groups of comparative experiments are conducted. Figure 18 As shown, when both the positive electrode and the negative electrode are carbon electrodes, the first group added 0.75M ZnAc2, 0.75M MnAc2, and 3M KCl between the positive electrode and the negative electrode, and the second group added 0.75M ZnCl2, 0.75M MnCl2, and 3M KAc between the positive electrode and the negative electrode; the charge and discharge current set in this comparative experiment is 2mA, the charging capacity is 1mAh, and the discharge is to 0V; the experimental results are characterized by a table showing the relationship between the number of battery cycles and the discharge capacity.

[0129] Figure 18The experimental results presented show that when ZnCl2, MnCl2, and KAc are added between the positive and negative electrodes, the discharge capacity remains stable with increasing cycles, eliminating the need for tedious weighing steps and allowing the volume of the concentrated solution to be prepared. This suggests that, provided the overall positive and negative ion content of the solution remains constant, a concentrated solution of ZnCl2, MnCl2, and KAc combined with an aqueous solution of the glue is an improvement; alternatively, KAc can be incorporated into the aqueous solution of the glue.

[0130] The above description is merely an exemplary embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural transformation made by utilizing the contents of the present invention's description and drawings under the technical concept of the present invention, or directly / indirectly applied in other related technical fields, is included in the patent protection scope of the present invention.

Claims

1. An aqueous battery, characterized in that: The aqueous battery comprises: an electrode pair, the electrode pair comprising a positive electrode and a negative electrode; a mesh separator disposed between the positive electrode and the negative electrode; The polyanion electrolyte layer is distributed on the mesh diaphragm; the polyanion electrolyte layer includes a polyanion polymer, a monovalent positive ion salt and a multivalent positive ion salt, and the polyanion polymer includes a macromolecule of at least one of a carboxyl group, a sulfonic acid group and a phosphonic acid group.

2. The aqueous battery according to claim 1, wherein The positive electrode is configured as a manganese dioxide electrode, the negative electrode is configured as a zinc electrode, the multivalent positive ion salt includes a first positive ion, the size of the first positive ion is larger than that of the zinc ion, and the first positive ion cannot be inserted into the manganese dioxide lattice of the positive electrode.

3. The aqueous battery according to claim 1, wherein The positive electrode and the negative electrode are configured as current collector electrodes, the multivalent positive ion salt comprises a zinc salt and a manganese salt, the monovalent positive ion salt comprises a second positive ion, the size of the second positive ion is larger than that of the zinc ion, and the second positive ion cannot be inserted into the manganese dioxide lattice of the positive electrode.

4. The aqueous battery according to claim 1, wherein The polyanion electrolyte layer contains mediator ions, and the polyanion polymer is used to inhibit the shuttling reaction of the mediator ions between the positive electrode and the negative electrode.

5. The aqueous battery according to claim 4, wherein The mediator ions include iron ions, the negative electrode does not contain a target metal element, and a standard electrode potential of a half-reaction of the target metal element in a neutral solution is greater than a standard electrode potential of a half-reaction of iron in a neutral solution.

6. The aqueous battery according to claim 3, wherein: The current collector electrode comprises activated carbon, and at least part of the capacitance of the aqueous battery is provided by the supercapacitor function of the activated carbon.

7. A method for manufacturing an aqueous battery, for manufacturing the aqueous battery according to any one of claims 1 to 6, characterized in that: The method for manufacturing the aqueous battery comprises the following steps: Pre-adding the monovalent positive ion salt and / or the multivalent positive ion salt to the electrode pair; In the case where the monovalent positive ion salt is pre-added to the electrode pair, the aqueous solution of the polyanionic polymer and the concentrated solution of the multivalent positive ion salt are sequentially added to the electrode pair; In the case where the multivalent positive ion salt is pre-added to the electrode pair, a concentrated solution of the monovalent positive ion salt and an aqueous solution of the polyanion polymer are sequentially added to the electrode pair, or a polyanion solution is added to the electrode pair; the polyanion solution is formed by mixing the polyanion polymer with the monovalent positive ion salt; In the case where the monovalent positive ion salt and the multivalent positive ion salt are added to the electrode pair in advance, the aqueous solution of the polyanionic polymer is added to the electrode pair.

8. A method for manufacturing an aqueous battery, for manufacturing the aqueous battery according to any one of claims 1 to 6, characterized in that: The method for manufacturing the aqueous battery comprises the following steps: Adding a polyanion solution or an aqueous solution of the polyanion polymer to the electrode pair; the polyanion solution is formed by mixing the polyanion polymer with the monovalent positive ion salt; In the case where the polyanion solution is added to the electrode pair, a concentrated solution of the multivalent cation salt is added to the electrode pair; In the case where the aqueous solution of the polyanionic polymer is added to the electrode pair, the concentrated solution of the monovalent positive ion salt and the concentrated solution of the multivalent positive ion salt are sequentially added to the electrode pair.

9. The production method according to claim 7 or 8, characterized in that: The polyanion solution is prepared by any of the following methods: adding a polyanionic polymer to the solution of the monovalent positive ion salt to form the polyanionic solution; dissolving the monovalent positive ion salt in the aqueous solution of the polyanionic polymer to form the polyanionic solution; The concentrated solution of the monovalent cationic salt is mixed with the aqueous solution of the polyanionic polymer to form the polyanionic solution.

10. The production method according to claim 7 or 8, characterized in that: In the case where the concentrated solution of the monovalent positive ion salt is added to the electrode pair, the monovalent positive ion salt comprises a single molecule of an organic acid.

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