A negative electrode, a rechargeable aqueous zinc-ion battery and its preparation method

Abstract

This invention discloses a negative electrode sheet, a rechargeable aqueous zinc-ion battery, and a method for preparing the same. The negative electrode sheet includes a negative electrode current collector, a zinc negative electrode material layer disposed on the negative electrode current collector, and a Prussian blue layer disposed on the zinc negative electrode material layer. This invention introduces a Prussian blue passivation layer on the surface of the zinc negative electrode material layer of the negative electrode sheet. Prussian blue possesses chemical stability and catalytic activity, enabling it to participate in the construction of the solid electrolyte during charge and discharge, thus forming a more stable passivation layer on the zinc negative electrode surface, slowing down the growth of zinc dendrites, maintaining battery capacity, and improving battery life.

Description

Technical Field

[0001] This invention relates to the field of battery technology, and in particular to a negative electrode, a rechargeable aqueous zinc-ion battery, and a method for preparing the same. Background Technology

[0002] Batteries, as a source of energy, play a vital role in fields such as computers, smart cards, portable medical devices, and electric vehicles. Currently, chemical batteries are the most widely used and applied type of battery, closely related to human socio-economic activities.

[0003] Rechargeable aqueous zinc-ion batteries, as a type of chemical battery, have advantages such as low cost, environmental friendliness, heavy load capacity, good low-temperature performance and leak-proof performance, and high performance-price ratio. They are widely used in various civilian and industrial scenarios. For example, they are the preferred portable power source for equipment such as defensive tactical radios, field telephones, and smart terminal devices, or as a backup power source, or as a power source for instruments and equipment such as flash cameras, miniature radios, video cameras, walkie-talkies, pagers, shavers, palm-sized color TVs and game consoles, toys, telemetry devices, alarms, calculators, hearing aids, flashlights, and electric clocks.

[0004] However, the main problem with rechargeable aqueous zinc-ion batteries is attributed to the performance defects of the zinc metal anode. Due to uneven electric field distribution and tip effects on the electrode surface, dendrites can form on the zinc metal anode. The presence of dendrites exacerbates parasitic reactions in electrolyte decomposition, generates more byproducts, and increases electrode interfacial impedance. Continuously growing dendrites can cause internal short circuits, leading to rapid capacity decay. Therefore, rechargeable aqueous zinc batteries are limited by the dendrite problem of the zinc metal anode, and their overall cycle stability cannot meet the requirements for practical applications.

[0005] Therefore, existing technologies still need to be improved and developed. Summary of the Invention

[0006] In view of the shortcomings of the prior art, the purpose of this invention is to provide a negative electrode sheet, a rechargeable aqueous zinc-ion battery and a method for preparing the same, in order to solve the problem that the zinc metal negative electrode of existing rechargeable aqueous zinc-ion batteries is prone to dendrite formation, resulting in poor cycle performance.

[0007] The technical solution of the present invention is as follows:

[0008] In a first aspect, the present invention provides a negative electrode sheet, comprising a negative electrode current collector, a zinc negative electrode material layer disposed on the negative electrode current collector, and a Prussian blue layer disposed on the zinc negative electrode material layer.

[0009] Optionally, the zinc anode material layer comprises zinc metal and a conductive agent.

[0010] A second aspect of the present invention provides a rechargeable aqueous zinc-ion battery, wherein the negative electrode sheet of the present invention as described above is included.

[0011] Optionally, the rechargeable aqueous zinc-ion battery further includes:

[0012] Substrate;

[0013] A positive electrode sheet is disposed opposite to a negative electrode sheet on the same surface of a substrate; the positive electrode sheet includes a positive current collector and a manganese dioxide positive electrode material layer disposed on the positive current collector, the positive current collector being attached to the substrate; the negative electrode sheet has a negative current collector attached to the substrate.

[0014] A gel-like electrolyte layer containing zinc and manganese salts is disposed on the manganese dioxide cathode material layer and the Prussian blue layer.

[0015] A third aspect of the present invention provides a method for preparing the rechargeable aqueous zinc-ion battery as described above, comprising the steps of:

[0016] Provide substrate;

[0017] A negative current collector and a positive current collector are formed oppositely on the same surface of the substrate by dispensing printing;

[0018] A zinc anode material layer with the same planar shape as the negative electrode current collector is printed by dispensing onto the negative electrode current collector, and a Prussian blue layer with the same planar shape as the zinc anode material layer is prepared on the zinc anode material layer;

[0019] A manganese dioxide cathode material layer with the same planar shape as the cathode current collector is printed onto the cathode current collector by dispensing adhesive.

[0020] A gel-like electrolyte layer containing zinc salt and manganese salt is disposed on the Prussian blue layer and the manganese dioxide positive electrode material layer to obtain the rechargeable aqueous zinc-ion battery.

[0021] Optionally, the step of dispensing and printing the negative electrode current collector and the positive electrode current collector oppositely disposed on the same surface of the substrate specifically includes:

[0022] Provide carbon paste;

[0023] The carbon paste is dispensing and printing onto the substrate to form interdigitated, oppositely arranged negative and positive current collectors; the dispensing and printing height is 0.2-2 mm, the dispensing and printing temperature is 30-40℃, the dispensing and printing speed is 1-50 mm / min, and the dispensing and printing pressure is 10-50 kPa.

[0024] Optionally, the step of dispensing and printing a zinc negative electrode material layer with the same planar shape as the negative electrode current collector onto the negative electrode current collector specifically includes:

[0025] Zinc powder is mixed with carbon paste to obtain zinc ink;

[0026] The zinc ink is dispensing and printing onto the negative electrode current collector to form a zinc negative electrode material layer with the same planar shape as the negative electrode current collector; the dispensing and printing height is 0.2-2mm, the dispensing and printing temperature is 30-40℃, the dispensing and printing speed is 1-50mm / min, the dispensing and printing pressure is 20-70kPa, and the number of dispensing and printing layers is 1-5.

[0027] Optionally, a Prussian blue layer with the same planar shape as the zinc anode material layer is prepared on the zinc anode material layer by electroplating deposition; the voltage used in the electroplating deposition method is 0.5V, the frequency used in the electroplating deposition method is 1Hz, and the number of cycles used in the electroplating deposition method is 100-500.

[0028] Optionally, the step of dispensing and printing a manganese dioxide cathode material layer with the same planar shape as the cathode current collector onto the cathode current collector specifically includes:

[0029] Manganese dioxide is mixed with carbon paste to obtain manganese dioxide ink;

[0030] The manganese dioxide ink is dispensing and printing onto the positive electrode current collector to form a manganese dioxide positive electrode material layer with the same planar shape as the positive electrode current collector. The dispensing and printing height is 0.2-2 mm, the dispensing and printing temperature is 30-40℃, the dispensing and printing speed is 1-50 mm / min, the dispensing and printing pressure is 10-50 kPa, and the number of dispensing and printing layers is 1-5.

[0031] Optionally, the method for preparing the gel-like electrolyte containing zinc and manganese salts includes the following steps:

[0032] Lithium chloride, zinc chloride, manganese sulfate, polyvinyl alcohol and water are mixed and stirred at 50-90°C for 1-5 hours to obtain the gel-like electrolyte containing zinc and manganese salts.

[0033] Beneficial effects: This invention introduces a Prussian blue passivation layer on the surface of the zinc anode material layer of the negative electrode sheet. Prussian blue has chemical stability and catalytic activity, and can participate in the construction of solid electrolyte during charging and discharging, so that a more stable passivation layer is formed on the surface of the zinc anode, slowing down the growth of zinc dendrites, maintaining battery capacity, and improving battery life. Attached Figure Description

[0034] Figure 1This is a schematic diagram of the cross-sectional structure of the negative electrode sheet in the direction perpendicular to the negative electrode current collector in an embodiment of the present invention.

[0035] Figure 2 This is a schematic diagram of the preparation process of a rechargeable aqueous zinc-ion battery in an embodiment of the present invention.

[0036] Figure 3 This is a graph showing the cycle test results of the rechargeable aqueous zinc-ion battery in Embodiment 1 of the present invention.

[0037] Figure 4 The graph shows the cycle test results of the rechargeable aqueous zinc-ion battery in Comparative Example 1 of this invention. Detailed Implementation

[0038] This invention provides a negative electrode sheet, a rechargeable aqueous zinc-ion battery, and a method for preparing the same. To make the objectives, technical solutions, and effects of this invention clearer and more explicit, the invention is further described in detail below. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0039] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of this invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

[0040] This invention provides a negative electrode sheet, such as... Figure 1 As shown, it includes a negative electrode current collector 3, a zinc negative electrode material layer 4 disposed on the negative electrode current collector, and a Prussian blue layer 5 disposed on the zinc negative electrode material layer 4.

[0041] In this embodiment of the invention, a Prussian blue passivation layer is introduced on the surface of the zinc anode material layer of the negative electrode sheet. Prussian blue has chemical stability and catalytic activity, and can participate in the construction of solid electrolyte during charging and discharging, so that a more stable passivation layer is formed on the surface of the zinc anode, slowing down the growth of zinc dendrites, maintaining battery capacity, and improving battery life.

[0042] In one embodiment, the zinc anode material layer comprises zinc metal and a conductive agent. The conductive agent includes, but is not limited to, carbon materials. The carbon materials include, but are not limited to, graphite, carbon black, graphene, and carbon nanotubes.

[0043] In one embodiment, the negative electrode current collector includes, but is not limited to, a carbon-based current collector.

[0044] This invention also provides a rechargeable aqueous zinc-ion battery, comprising the negative electrode sheet described above. The rechargeable aqueous zinc-ion battery provided in this embodiment exhibits stable capacity and a long cycle life during cycling. Specifically, because a Prussian blue passivation layer is introduced onto the surface of the zinc negative electrode material layer in the negative electrode sheet, Prussian blue, with its chemical stability and catalytic activity, participates in the construction of the solid electrolyte during charging and discharging, resulting in a more stable passivation layer on the zinc negative electrode surface. This slows down the growth of zinc dendrites, thereby maintaining battery capacity and improving battery life.

[0045] In one embodiment, the rechargeable aqueous zinc-ion battery further includes:

[0046] Substrate;

[0047] A positive electrode sheet is disposed opposite to a negative electrode sheet on the same surface of a substrate; the positive electrode sheet includes a positive current collector and a manganese dioxide positive electrode material layer disposed on the positive current collector, the positive current collector being attached to the substrate; the negative electrode sheet has a negative current collector attached to the substrate.

[0048] A gel-like electrolyte layer containing zinc and manganese salts is disposed on the manganese dioxide cathode material layer and the Prussian blue layer.

[0049] In this embodiment, the rechargeable aqueous zinc-ion battery includes a substrate, a positive electrode and a negative electrode disposed opposite to each other on the same surface of the substrate without contact, and a gel-like electrolyte layer containing zinc salts and manganese salts disposed on the positive electrode and the negative electrode. The positive electrode includes a positive current collector and a manganese dioxide positive electrode material layer disposed on the positive current collector. The positive current collector is attached to the substrate, and the manganese dioxide positive electrode material layer is attached to the gel-like electrolyte layer containing zinc salts and manganese salts. The negative electrode includes a negative current collector, a zinc negative electrode material layer disposed on the negative current collector, and a Prussian blue layer disposed on the zinc negative electrode material layer. The negative current collector is attached to the substrate, and the Prussian blue layer is attached to the gel-like electrolyte layer containing zinc salts and manganese salts.

[0050] In one embodiment, the positive electrode and the negative electrode are interdigitated and disposed opposite each other on the same surface of the substrate.

[0051] In one embodiment, the manganese dioxide material layer comprises manganese dioxide and a conductive agent, wherein the conductive agent includes, but is not limited to, carbon materials. The carbon materials include, but are not limited to, graphite, carbon black, graphene, and carbon nanotubes.

[0052] In one embodiment, the positive current collector includes, but is not limited to, a carbon-based current collector.

[0053] This invention also provides a method for preparing the rechargeable aqueous zinc-ion battery described above, such as... Figure 2 As shown, the steps include:

[0054] S1, Provide substrate 1;

[0055] S2. A negative current collector 3 and a positive current collector 2 are formed opposite to each other on the same surface of the substrate 1 by dispensing and printing.

[0056] S3. Apply adhesive to the negative electrode current collector 3 and print a zinc negative electrode material layer 4 with the same planar shape as the negative electrode current collector 3. Prepare a Prussian blue layer 5 with the same planar shape as the zinc negative electrode material layer 4 on the zinc negative electrode material layer 4.

[0057] S4. Apply adhesive to the positive current collector 2 and print a manganese dioxide positive electrode material layer 6 with the same planar shape as the positive current collector 2;

[0058] S5. A gel-like electrolyte layer 7 containing zinc salt and manganese salt is disposed on the Prussian blue layer 5 and the manganese dioxide positive electrode material layer 6 to obtain the rechargeable aqueous zinc-ion battery.

[0059] Compared with traditional battery manufacturing technology, the preparation method provided in this invention has the following advantages: 1) It can manufacture batteries with the required complex structure; 2) The electrode shape and thickness can be precisely controlled; 3) The prepared battery structure has high stability and is safe to operate; 4) It is low-cost, environmentally friendly and easy to operate; 5) The battery can be directly integrated with other electrical appliances, eliminating the steps of equipment assembly and packaging.

[0060] This invention employs dispensing printing technology, eliminating the need for masks, to fabricate novel electrode structures with larger surface areas, higher areal density, shorter diffusion paths, and lower resistance to ion transport, thereby improving the energy and power density of the battery. Furthermore, dispensing printing significantly reduces material waste and saves time. In summary, dispensing printing opens new avenues for the rapid fabrication of batteries with complex structures and high performance. This technology facilitates battery manufacturing, improves electrochemical performance, and precisely controls battery geometry (such as porosity, size, and morphology) as well as the structure of electrodes and electrolytes, enabling the fabrication of multifunctional micro-batteries from microscopic to macroscopic scales. The rechargeable aqueous zinc-ion battery prepared using this invention is not only low-cost but also possesses advantages such as flexibility, foldability, and portability, showing broad application prospects.

[0061] In step S1, in one embodiment, the substrate is a flexible substrate, which can be used to fabricate a flexible sheet-like battery with properties such as bendability and foldability. In a specific embodiment, the substrate is a polyethylene terephthalate (PET) substrate or a polyimide (PI) substrate.

[0062] In step S2, in one embodiment, the step of dispensing and printing the negative current collector and the positive current collector disposed opposite to each other on the same surface of the substrate specifically includes:

[0063] S21, Provide carbon paste;

[0064] S22. The carbon paste is dispensing and printing onto the substrate to form interdigitated negative and positive current collectors arranged opposite each other; the dispensing and printing height is 0.2-2 mm, the dispensing and printing temperature is 30-40℃, the dispensing and printing speed is 1-50 mm / min, and the dispensing and printing pressure is 10-50 kPa.

[0065] In step S21, in one embodiment, the method for preparing the carbon paste includes, but is not limited to, the following steps:

[0066] Carbon materials, water-based resin, and ethylene glycol are mixed evenly in a certain mass ratio to form a carbon slurry.

[0067] In a further embodiment, carbon materials, aqueous resin and ethylene glycol are mixed evenly in a mass ratio of 4:1:0.5 to form a carbon slurry.

[0068] In a further embodiment, the carbon material is selected from at least one of graphite, carbon black, graphene, and carbon nanotubes, but is not limited thereto.

[0069] In step S22, the positive current collector includes a root and a finger connected to the root, the finger including a plurality of interdigitated fingers with the same spacing; the negative current collector includes a root and a finger connected to the root, the finger including a plurality of interdigitated fingers with the same spacing, the negative current collector and the positive current collector arranged opposite to each other in the shape of interdigitated fingers, that is, the interdigitated fingers of the positive current collector and the interdigitated fingers of the negative current collector are alternately arranged.

[0070] In one embodiment, in the step of forming the oppositely arranged negative and positive current collectors in an interdigitated shape, the number of interdigitated fingers is 1-10 pairs, the spacing between the interdigitated fingers is 0.1-5 mm, and the width of the interdigitated fingers is 0.5-5 mm. Taking 5 pairs of interdigitated fingers, a spacing of 1 mm, and a width of 2 mm as an example, the positive current collector has 5 interdigitated fingers, each with a width of 2 mm, and the negative current collector has 5 interdigitated fingers, each with a width of 2 mm. The interdigitated fingers of the positive and negative current collectors are alternately arranged, and the spacing between adjacent positive and negative current collector interdigitated fingers is 1 mm.

[0071] In one embodiment, after dispensing and printing the interdigitated negative and positive current collectors in an opposite arrangement on the substrate, the process further includes drying at a temperature of 30-80°C for 1-5 hours.

[0072] In step S3, in one embodiment, the step of dispensing and printing a zinc negative electrode material layer with the same planar shape as the negative electrode current collector onto the negative electrode current collector specifically includes:

[0073] S31. Mix zinc powder with carbon paste to obtain zinc ink;

[0074] S32. The zinc ink is dispensing and printing onto the negative electrode current collector to form a zinc negative electrode material layer with the same planar shape as the negative electrode current collector; the dispensing and printing height is 0.2-2mm, the dispensing and printing temperature is 30-40℃, the dispensing and printing speed is 1-50mm / min, the dispensing and printing pressure is 20-70kPa, and the number of dispensing and printing layers is 1-5.

[0075] In step S31, the carbon paste may be the same type of carbon paste as that used in step S21.

[0076] In one embodiment, the zinc powder in the zinc ink has a mass content of 10-98%.

[0077] In a further embodiment, the zinc powder in the zinc ink has a mass content of 50-98%.

[0078] In one embodiment, the step of mixing zinc powder with carbon paste to obtain zinc ink specifically includes:

[0079] Mix zinc powder with carbon slurry and magnetically stir at 500-3000 r / min for 0.5-5 h at 20-50℃. Then sonicate in a cell pulverizing ultrasonic disperser for 5-30 min at 100-300 W. During sonication, work for 10-30 s and rest for 10-30 s, repeating this cycle (i.e., work for 10-30 s, rest for 10-30 s, work for 10-30 s, rest for 10-30 s).

[0080] In one embodiment, after the zinc negative electrode material layer with the same planar shape as the negative electrode current collector is printed on the negative electrode current collector by dispensing adhesive, the step further includes drying at a temperature of 30-60°C for 1-5 hours.

[0081] In step S3, in one embodiment, a Prussian blue layer with the same planar shape as the zinc anode material layer is prepared on the zinc anode material layer by electroplating deposition; the voltage used in the electroplating deposition method is 0.5V, the frequency used in the electroplating deposition method is 1Hz, and the number of cycles used in the electroplating deposition method is 100-500 times.

[0082] In one embodiment, the electroplating deposition method uses an electroplating solution comprising ferric chloride, potassium ferricyanide, potassium chloride, and hydrochloric acid. Based on a volume of 1 L of hydrochloric acid, the concentration of ferric chloride is 2-5 mM (i.e., 1 L of hydrochloric acid contains 2-5 mmol of ferric chloride), the concentration of potassium ferricyanide is 2-6 mM (i.e., 1 L of hydrochloric acid contains 2-6 mmol of potassium ferricyanide), the concentration of potassium chloride is 0.1-1 mM (i.e., 1 L of hydrochloric acid contains 0.1-1 mmol of potassium chloride), and the concentration of hydrogen chloride in the hydrochloric acid is 0.1-1 mM.

[0083] In one embodiment, after preparing a Prussian blue layer with the same planar shape as the zinc anode material layer on the zinc anode material layer by electroplating deposition, the process further includes drying at a temperature of 30-50°C for 5-30 minutes.

[0084] In step S4, in one embodiment, the step of dispensing and printing a manganese dioxide cathode material layer with the same planar shape as the cathode current collector onto the cathode current collector specifically includes:

[0085] S41. Mix manganese dioxide with carbon paste to obtain manganese dioxide ink;

[0086] S42. The manganese dioxide ink is dispensing and printing onto the positive electrode current collector to form a manganese dioxide positive electrode material layer with the same planar shape as the positive electrode current collector. The height of the dispensing and printing is 0.2-2mm (i.e., the distance between the print head of the dispensing printer and the substrate is 0.2-2mm), the temperature of the dispensing and printing is 30-40℃, the speed of the dispensing and printing is 1-50mm / min, the pressure of the dispensing and printing is 10-50kPa, and the number of layers is 1-5.

[0087] In step S41, the carbon paste may be the same type of carbon paste as that used in step S21.

[0088] In one embodiment, the manganese dioxide ink contains 10-80% manganese dioxide by mass.

[0089] In a further embodiment, the manganese dioxide ink contains 30-80% manganese dioxide by mass.

[0090] In one embodiment, the step of mixing manganese dioxide with carbon paste to obtain manganese dioxide ink specifically includes:

[0091] Manganese dioxide is mixed with carbon slurry and magnetically stirred at 500-3000 r / min for 0.5-5 h at 20-50℃. Then, it is ultrasonicated in a cell pulverizer for 5-30 min at 100-300 W. The ultrasonic process is repeated for 20-30 seconds, followed by a 10-30 second rest period.

[0092] In one embodiment, after the manganese dioxide positive electrode material layer with the same planar shape as the positive electrode current collector is printed on the positive electrode current collector by dispensing, the step further includes drying it at a temperature of 30-60°C for 1-5 hours.

[0093] In step S5, in one embodiment, the method for preparing the gel-like electrolyte containing zinc salt and manganese salt includes the following steps:

[0094] Lithium chloride, zinc chloride, manganese sulfate, polyvinyl alcohol and water are mixed and stirred at 50-90°C for 1-5 hours to obtain the gel-like electrolyte containing zinc and manganese salts.

[0095] In one embodiment, the ratio of lithium chloride to water is (3-10) mol: 1L, the ratio of zinc chloride to water is (1-5) mol: 1L, the ratio of manganese sulfate to water is 0.1 mol: 1L, and the ratio of polyvinyl alcohol to water is 0.1 g: 1 mL.

[0096] In one embodiment, the water is ultrapure water.

[0097] The following detailed description uses specific examples.

[0098] Example 1

[0099] Preparation of rechargeable aqueous zinc-ion batteries:

[0100] Graphite powder, water-based resin, and ethylene glycol are mixed evenly in a mass ratio of 4:1:0.5 to form a carbon paste;

[0101] The carbon paste and zinc powder were mixed and magnetically stirred at 3000 r / min for 2 hours at 35°C. Then, the mixture was dispersed in a cell-pulverizing ultrasonic disperser for 20 minutes at 300 W. The ultrasonic process was repeated for 10 seconds followed by 30 seconds of rest to obtain zinc ink, in which the zinc powder content was 50% by mass.

[0102] The carbon paste and manganese dioxide were mixed and magnetically stirred at 2000 r / min at 30°C for 1 hour. Then, the mixture was dispersed in a cell-disinfecting ultrasonic disperser for 10 minutes at 200W. The ultrasonic process was repeated for 30 seconds followed by a 30-second rest period to obtain manganese dioxide ink, which contained 30% manganese dioxide by mass.

[0103] Carbon paste was dispensing and printing onto a PET substrate to form interdigitated positive and negative current collectors arranged opposite each other (wherein, the dispensing and printing height was 0.2 mm, the dispensing and printing temperature was 40 °C, the dispensing and printing speed was 9 mm / min, the dispensing and printing pressure was 10 kPa, the width of the interdigitated fingers was 2 mm, the number of interdigitated fingers was 4 pairs, and the spacing between the interdigitated fingers was 1 mm), and then dried at 60 °C for 4 h.

[0104] Zinc ink was dispensing and printing onto a dry negative electrode current collector to form a zinc negative electrode material layer, and its planar shape was the same as that of the negative electrode current collector (wherein, the dispensing and printing height was 0.2 mm, the dispensing and printing temperature was 40 °C, the dispensing and printing speed was 5 mm / min, the dispensing and printing pressure was 20 kPa, and the number of dispensing and printing layers was 3). Then it was dried at 50 °C for 2 h.

[0105] A Prussian blue layer was electroplated onto a dry zinc anode material layer, with the same planar shape as the zinc metal anode (the electroplating voltage was 0.5V, the electroplating frequency was 1Hz, the number of cycles was 120, and the electroplating solution was a mixed solution composed of 3mM ferric chloride, 4mM potassium ferricyanide, and 0.8mM potassium chloride dispersed in 0.8mM hydrochloric acid). Then, it was dried at 40℃ for 20min.

[0106] Manganese dioxide ink was dispensing and printing onto the positive current collector to form a manganese dioxide positive electrode material layer, and its planar shape was the same as that of the positive current collector (wherein, the dispensing and printing height was 0.2 mm, the dispensing and printing temperature was 40℃, the dispensing and printing speed was 5 mm / min, the dispensing and printing pressure was 10 kPa, and the number of dispensing and printing layers was 3). Then it was dried at 40℃ for 1 hour.

[0107] 4M lithium chloride, 5M zinc chloride, 0.1M manganese sulfate and 0.1 g / mL polyvinyl alcohol were mixed in ultrapure water and stirred at 80°C for 2 h to obtain a gel-like electrolyte containing zinc salt and manganese salt.

[0108] A rechargeable aqueous zinc-ion battery is obtained by placing a gel-like electrolyte containing zinc and manganese salts on a dry Prussian blue layer and a manganese dioxide cathode material layer.

[0109] Comparative Example 1

[0110] The preparation steps are basically the same as in Example 1, except that the electroplating deposition of Prussian blue is not performed.

[0111] The rechargeable aqueous zinc-ion batteries in Example 1 and Comparative Example 1 were subjected to cycle performance tests, and the results are as follows: Figure 3 As shown in Examples 1 and 4 (Comparative Example 1), the results indicate that, compared to the untreated pure zinc anode (Comparative Example 1), the battery capacity decays rapidly during cycling. Figure 4 A rechargeable aqueous zinc-ion battery (Example 1) with a Prussian blue layer deposited on the zinc anode surface can effectively suppress zinc dendrite growth during charging and discharging. The irreversible zinc loss caused by the formation of zinc dendrites is less, resulting in high battery capacity retention and long battery life.

[0112] In summary, this invention provides a negative electrode sheet, a rechargeable aqueous zinc-ion battery, and a method for preparing the same. This invention introduces a Prussian blue passivation layer onto the surface of the zinc negative electrode material layer of the negative electrode sheet. Prussian blue possesses chemical stability and catalytic activity, enabling it to participate in the construction of the solid electrolyte during charging and discharging, thus forming a more stable passivation layer on the zinc negative electrode surface, slowing the growth of zinc dendrites, maintaining battery capacity, and improving battery life.

[0113] It should be understood that the application of the present invention is not limited to the examples above. Those skilled in the art can make improvements or modifications based on the above description, and all such improvements and modifications should fall within the protection scope of the appended claims.

Claims

1. A rechargeable aqueous zinc-ion battery, characterized in that, The rechargeable aqueous zinc ion battery comprises a substrate; A negative electrode sheet comprising a negative electrode current collector, a zinc negative electrode material layer disposed on the negative electrode current collector, and a Prussian blue layer disposed on the zinc negative electrode material layer; a positive electrode sheet disposed on the same surface of the substrate opposite to the negative electrode sheet; the positive electrode sheet comprises a positive electrode current collector, a manganese dioxide positive electrode material layer disposed on the positive electrode current collector, and the positive electrode current collector is attached to the substrate; the negative electrode current collector in the negative electrode sheet is attached to the substrate; A gel electrolyte layer containing zinc salt and manganese salt is disposed on the manganese dioxide positive electrode material layer and the Prussian blue layer; The preparation method of the gel electrolyte containing zinc salt and manganese salt comprises the following steps: Mixing lithium chloride, zinc chloride, manganese sulfate, polyvinyl alcohol and water, stirring at a temperature of 50-90℃ for 1-5h to obtain the gel electrolyte containing zinc salt and manganese salt; A Prussian blue layer with the same planar shape as the zinc negative electrode material layer is prepared on the zinc negative electrode material layer by electroplating deposition.

2. A method of preparing a rechargeable aqueous zinc-ion battery as claimed in claim 1, characterized in that, Comprising the steps of: Providing a substrate; Forming the negative electrode current collector and the positive electrode current collector opposite to each other on the same surface of the substrate by dispensing printing; Dispensing printing a zinc negative electrode material layer with the same planar shape as the negative electrode current collector on the negative electrode current collector, and preparing a Prussian blue layer with the same planar shape as the zinc negative electrode material layer on the zinc negative electrode material layer; Dispensing printing a manganese dioxide positive electrode material layer with the same planar shape as the positive electrode current collector on the positive electrode current collector; A gel electrolyte layer containing zinc salt and manganese salt is disposed on the Prussian blue layer and the manganese dioxide positive electrode material layer to obtain the rechargeable aqueous zinc ion battery; The preparation method of the gel electrolyte containing zinc salt and manganese salt comprises the following steps: Mixing lithium chloride, zinc chloride, manganese sulfate, polyvinyl alcohol and water, stirring at a temperature of 50-90℃ for 1-5h to obtain the gel electrolyte containing zinc salt and manganese salt.

3. The production method according to claim 2, characterized by, The step of dispensing printing the negative electrode current collector and the positive electrode current collector opposite to each other on the same surface of the substrate specifically comprises: Providing carbon paste; Dispensing printing the carbon paste on the substrate to form the negative electrode current collector and the positive electrode current collector opposite to each other in an interdigital shape; the dispensing printing has a height of 0.2-2mm, a temperature of 30-40℃, a speed of 1-50mm / min, and a pressure of 10-50kPa.

4. The production method according to claim 3, characterized by, The step of dispensing printing the zinc negative electrode material layer with the same planar shape as the negative electrode current collector on the negative electrode current collector specifically comprises: Mixing zinc powder and carbon paste to obtain zinc ink; The zinc ink is dispensing printed on the negative current collector to form a zinc negative material layer with the same planar shape as the negative current collector; the dispensing printing has a height of 0.2-2mm, a temperature of 30-40℃, a speed of 1-50mm / min, a pressure of 20-70kPa, and 1-5 layers.

5. The production method according to claim 4, characterized by, A Prussian blue layer with the same planar shape as the zinc negative material layer is prepared on the zinc negative material layer by an electroplating deposition method; the electroplating deposition method uses a voltage of 0.5V, a frequency of 1Hz, and 100-500 cycles.

6. The production method according to claim 5, characterized by, The step of dispensing printing a manganese dioxide positive material layer with the same planar shape as the positive current collector on the positive current collector specifically comprises: Manganese dioxide is mixed with carbon paste to obtain manganese dioxide ink; The manganese dioxide ink is dispensing printed on the positive current collector to form a manganese dioxide positive material layer with the same planar shape as the positive current collector, the dispensing printing has a height of 0.2-2mm, a temperature of 30-40℃, a speed of 1-50mm / min, a pressure of 10-50kPa, and 1-5 layers.

7. The preparation method according to claim 3, characterized in that, The preparation method of the carbon paste comprises the following steps: Carbon material, water-based resin and ethylene glycol are mixed uniformly according to a certain mass ratio to form carbon paste. The carbon material is selected from at least one of graphite, carbon black, graphene and carbon nanotube.

8. The preparation method according to claim 4, characterized in that, The mass content of the zinc powder in the zinc ink is 10 98%.

9. The preparation method according to claim 5, characterized in that, The electroplating solution used in the electroplating deposition method comprises ferric chloride, potassium ferricyanide, potassium chloride and hydrochloric acid.

10. The method of claim 2, wherein, The substrate is a flexible substrate.

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