A composite current collector for zinc-based batteries and a preparation method thereof, a negative electrode sheet, and a zinc-based battery

Abstract

The present application relates to a kind of composite current collector for zinc-based battery and its preparation method, negative plate, zinc-based battery, belong to battery technical field.The composite current collector for zinc-based battery of the present application includes zinc base and the conductive layer attached on zinc base, the zinc base is zinc or zinc alloy or zinc-plated metal;The conductive layer includes metal powder and binder, the metal powder is at least one of copper powder, tin powder, magnesium powder, calcium powder, zinc powder, titanium powder, manganese powder, indium powder, lead powder, cadmium powder, palladium powder, bismuth powder, tungsten powder, vanadium powder.The conductive layer also includes conductive agent, and the conductive agent is at least one of graphite, acetylene black, graphene, carbon fiber, carbon nanotube, carbon fiber ball.The composite current collector for zinc-based battery of the present application sets up conductive layer on the surface of zinc base, and the conductive layer contains metal powder, both ensures the conductivity of current collector, and reduces the cost of current collector to some extent, and then reduces the cost of battery as a whole.

Description

Technical Field

[0001] This invention relates to a composite current collector for zinc-based batteries and its preparation method, a negative electrode sheet, and a zinc-based battery, belonging to the field of battery technology. Background Technology

[0002] Zinc-based batteries are batteries that use zinc as the active material, including zinc-manganese batteries, zinc-nickel batteries, zinc-lithium batteries, zinc-lithium-manganese batteries, zinc-aluminum batteries, zinc-silver batteries, zinc-air batteries, zinc-iron batteries, and zinc-sodium batteries. Zinc-based batteries possess characteristics such as being non-toxic, harmless, safe, high-power, high-capacity, high-energy, long-life, and low-cost, and have been widely used in various fields. The production process of these batteries produces no wastewater, exhaust gas, or harmful substances, making them more in line with current requirements for green energy.

[0003] Low cost is the most prominent feature of zinc-based batteries, as they use zinc as the electrode material, resulting in lower material costs. Furthermore, zinc-based batteries use an aqueous electrolyte, typically a potassium hydroxide solution, which not only improves safety but also significantly reduces battery costs.

[0004] In zinc-based batteries, copper strips or copper foils are generally used as the negative electrode current collector. As the price of copper is becoming increasingly expensive, the negative electrode current collector has become one of the bottlenecks in controlling the cost of zinc-based batteries. Summary of the Invention

[0005] This invention provides a composite current collector for zinc-based batteries to reduce the manufacturing cost of zinc-based batteries.

[0006] The present invention also provides a method for preparing the above-mentioned composite current collector for zinc-based batteries. The method uses readily available raw materials, has a simple process, and is easy to scale up for production.

[0007] The present invention also provides a negative electrode sheet for a zinc-based battery and a zinc-based battery using the negative electrode sheet, the battery having a low cost.

[0008] The technical solution adopted by the present invention to solve the above-mentioned technical problems is as follows:

[0009] A composite current collector for zinc-based batteries includes a zinc substrate and a conductive layer attached to the zinc substrate. The zinc substrate is zinc, a zinc alloy, or zinc-plated metal. The conductive layer includes metal powder and a binder. The metal powder is at least one of copper powder, tin powder, magnesium powder, calcium powder, zinc powder, titanium powder, manganese powder, indium powder, lead powder, cadmium powder, palladium powder, bismuth powder, tungsten powder, and vanadium powder.

[0010] The mass ratio of the metal powder to the binder is 50-95:5-35.

[0011] The conductive layer further includes a conductive agent, which is at least one of graphite, acetylene black, graphene, carbon fiber, carbon nanotubes, and carbon fiber spheres.

[0012] The conductive layer further includes an oxide, which is at least one of tin dioxide, zinc oxide, manganese dioxide, bismuth oxide, and indium oxide.

[0013] The conductive layer further includes nitrides, which are any one of calcium nitride, titanium nitride, magnesium nitride, and strontium nitride.

[0014] The conductive layer further includes a reinforcing agent, which is at least one of calcium titanate and lithium manganate.

[0015] The particle size of the metal powder is 200-2000 mesh.

[0016] The ratio of the thickness of the zinc substrate to the thickness of the conductive layer is 300-500:30-80.

[0017] A method for preparing the above-mentioned composite current collector for zinc-based batteries includes the following steps:

[0018] 1) Mix the metal powder, binder, and solvent evenly to obtain a conductive paste;

[0019] 2) Coat the conductive paste onto the zinc substrate surface and dry it to obtain the final product.

[0020] The drying temperature is 80-120℃. The drying time is 30-120 minutes, preferably 30-120 minutes.

[0021] A negative electrode sheet for zinc-based batteries includes a negative electrode current collector and a negative electrode material layer coated on the negative electrode current collector, wherein the negative electrode current collector is the aforementioned composite current collector for zinc-based batteries.

[0022] A zinc-based battery includes a positive electrode and a negative electrode, wherein the negative electrode is the aforementioned negative electrode for zinc-based batteries.

[0023] The beneficial effects of this invention are:

[0024] The composite current collector for zinc-based batteries of the present invention has a conductive layer disposed on the surface of a zinc substrate. The conductive layer contains metal powder, which not only ensures the conductivity of the current collector but also reduces the cost of the current collector to a certain extent, thereby reducing the overall battery cost. In addition, the conductive layer containing metal powder disposed on the surface of the zinc substrate forms a protective layer for the zinc substrate, increasing the difficulty of corrosion of the zinc substrate, extending the duration of the current collector's structural stability, and improving the battery's cycle performance. Attached Figure Description

[0025] Figure 1 The discharge curve of the zinc-based battery obtained by the composite current collector in Example 1 of the present invention is shown.

[0026] Figure 2The graph shows a comparison of the cycle curves of the zinc-based batteries obtained using the composite current collector in Examples 1-4. Detailed Implementation

[0027] To make the technical problems, technical solutions, and beneficial effects of this invention easier to understand, the invention will be described in detail below with reference to specific embodiments.

[0028] The composite current collector for zinc-based batteries of the present invention comprises a zinc substrate and a conductive layer attached to the zinc substrate. The zinc substrate is zinc or a zinc alloy. The conductive layer comprises metal powder and a binder. The metal powder is at least one of copper powder, tin powder, magnesium powder, calcium powder, zinc powder, titanium powder, manganese powder, indium powder, lead powder, cadmium powder, palladium powder, bismuth powder, tungsten powder, and vanadium powder. The zinc-based battery of the present invention is any one of zinc-manganese battery, zinc-nickel battery, zinc-lithium battery, zinc-lithium-manganese battery, zinc-aluminum battery, zinc-silver battery, zinc-air battery, zinc-iron battery, and zinc-sodium battery. The zinc substrate is any one of zinc foam, zinc mesh, zinc foil, and zinc plate. The zinc mesh is any one of inclined wire mesh, three-dimensional mesh, and perforated mesh. Preferably, it is a zinc mesh with a mesh size of 0.2-2 mm. The copper powder is preferably electrolytic copper.

[0029] The ratio of metal powder to binder can be set as needed. Generally, the amount of binder should not be too high, as excessive binder can negatively impact the cycle performance of zinc-based batteries, according to experimental results. Preferably, the mass ratio of metal powder to binder is 50-70:5-35.

[0030] Although metal powder has excellent conductivity, experimental results show that adding some carbon-based conductive agents can improve battery performance. Preferably, the conductive layer further includes a conductive agent, which is at least one of graphite, acetylene black, graphene, carbon fiber, carbon nanotubes, and carbon fiber spheres. The amount of conductive agent should not be excessive to avoid affecting the electrode potential; generally, the mass ratio of metal powder to conductive agent is 50-70:10-20.

[0031] The conductive layer also includes an oxide, which is at least one selected from tin dioxide, zinc oxide, manganese dioxide, bismuth oxide, and indium oxide. The mass ratio of metal powder to oxide is 50-70:8-50.

[0032] Furthermore, the conductive layer also includes a nitride, which is any one of calcium nitride, titanium nitride, magnesium nitride, and strontium nitride. The mass ratio of metal powder to nitride is 50-70:3-8.

[0033] Furthermore, the conductive layer also includes a reinforcing agent, which is at least one of calcium titanate and lithium manganese oxide. The mass ratio of metal powder to reinforcing agent is 50-70:0.5-1.5.

[0034] The adhesive is at least one of PVA, HEC, PAAS, HPMC, PEO, CMC, SBR, PVDF, and PTFE.

[0035] When preparing the composite current collector for zinc-based batteries according to the present invention, the slurry coating method can be either scraping or spraying.

[0036] Example 1

[0037] The zinc-based battery composite current collector of this embodiment includes a zinc substrate and conductive layers coated on both sides of the zinc substrate. The zinc substrate is a zinc mesh, and the conductive layers are composed of the following parts by weight: 50 parts copper powder and 55 parts binder. The binder consists of 50 parts SBR and 5 parts CMC. The copper powder has a particle size of 400 mesh. The zinc mesh is a skewing mesh with a thickness of 500 μm and a mesh aperture (the mesh is rhomboid, and the aperture is the side length of the rhombus) of 800 μm. The thickness of the conductive layer on each side of the zinc mesh is 50 μm.

[0038] The preparation method of the composite current collector for zinc-based batteries in this embodiment includes the following steps:

[0039] 1) Add 50 parts by weight of SBR and 5 parts by weight of CMC to 400 parts by weight of deionized water, stir for 30 minutes to mix evenly to obtain a glue solution, then add 50 parts by weight of copper powder to the glue solution and stir for 60 minutes to obtain a conductive paste.

[0040] 2) Coat the conductive paste onto both surfaces of the zinc mesh and dry at 60°C for 60 minutes to obtain the final product.

[0041] Example 2

[0042] The zinc-based battery composite current collector of this embodiment includes a zinc substrate and conductive layers coated on both sides of the zinc substrate. The zinc substrate is a zinc mesh, and the conductive layers are composed of the following parts by weight: 50 parts copper powder, 50 parts tin dioxide powder, and 35 parts binder. The binder consists of 30 parts SBR and 5 parts CMC. The copper powder has a particle size of 400 mesh, and the tin dioxide has a particle size of 20 μm. The zinc mesh is a skein mesh with a thickness of 350 μm and a mesh aperture (the mesh is rhomboid, and the aperture is the side length of the rhombus) of 1000 μm. The thickness of the conductive layer on each side is 30 μm.

[0043] The preparation method of the composite current collector for zinc-based batteries in this embodiment includes the following steps:

[0044] 1) Add 30 parts by weight of SBR and 5 parts by weight of CMC to 300 parts by weight of deionized water, stir for 30 minutes to mix evenly to obtain a glue solution, then add 50 parts by weight of copper powder and 50 parts by weight of tin dioxide powder to the glue solution in sequence, and stir for 80 minutes to obtain a conductive paste.

[0045] 2) Coat the conductive paste on both surfaces of the zinc mesh and dry at 80°C for 30 minutes to obtain the final product.

[0046] Example 3

[0047] The zinc-based battery composite current collector of this embodiment includes a zinc substrate and conductive layers coated on both sides of the zinc substrate. The zinc substrate is a zinc mesh, and the conductive layers are composed of the following parts by weight: 50 parts copper powder, 15 parts tin dioxide powder, and 22.5 parts binder. The binder consists of 20 parts SBR and 2.5 parts CMC. The copper powder has a particle size of 400 mesh, and the tin dioxide has a particle size of 20 μm. The zinc mesh is a skewing mesh with a thickness of 350 μm and a mesh aperture (the mesh is rhomboid, and the aperture is the side length of the rhombus) of 1000 μm. The thickness of the conductive layer on each side is 30 μm.

[0048] The preparation method of the composite current collector for zinc-based batteries in this embodiment includes the following steps:

[0049] 1) Add 20 parts by weight of SBR and 2.5 parts by weight of CMC to 250 parts by weight of deionized water, stir for 50 minutes to mix evenly to obtain a glue solution, then add 50 parts by weight of copper powder and 15 parts by weight of tin dioxide powder to the glue solution in sequence, and stir for 90 minutes to obtain a conductive paste.

[0050] 2) Coat the conductive paste onto both surfaces of the zinc mesh and dry at 100°C for 20 minutes to obtain the final product.

[0051] Example 4

[0052] The zinc-based battery composite current collector of this embodiment includes a zinc substrate and conductive layers coated on both sides of the zinc substrate. The zinc substrate is a zinc mesh. The conductive layers are composed of the following parts by weight: 50 parts copper powder, 15 parts tin dioxide powder, 1 part indium oxide, and 11.5 parts binder. The binder is composed of 10 parts SBR and 1.5 parts CMC. The copper powder has a particle size of 800 mesh, the tin dioxide has a particle size of 20 μm, and the indium oxide has a particle size of 70 nm. The zinc mesh is a skein mesh with a thickness of 350 μm and a mesh aperture (the mesh is rhomboid, and the aperture is the side length of the rhombus) of 1000 μm. The thickness of the conductive layer on each side is 35 μm.

[0053] The preparation method of the composite current collector for zinc-based batteries in this embodiment includes the following steps:

[0054] 1) Add 10 parts by weight of SBR and 1.5 parts by weight of CMC to 200 parts by weight of deionized water, stir for 30 minutes to mix evenly to obtain a glue solution. Then add 50 parts by weight of copper powder, 15 parts by weight of tin dioxide powder and 1 part by weight of indium oxide to the glue solution in sequence, and stir for 80 minutes to obtain a conductive paste.

[0055] 2) Coat the conductive paste onto both surfaces of the zinc mesh and dry at 120°C for 10 minutes to obtain the final product.

[0056] Example 5

[0057] The zinc-based battery composite current collector of this embodiment includes a zinc substrate and conductive layers coated on both sides of the zinc substrate. The zinc substrate is a zinc mesh. The conductive layers are composed of the following parts by weight: 50 parts copper powder, 12 parts tin dioxide powder, 1.5 parts bismuth oxide, 0.5 parts indium oxide, and 8 parts binder. The binder is composed of 7 parts SBR and 1 part CMC. The copper powder has a particle size of 400 mesh, the tin dioxide has a particle size of 20 μm, the bismuth oxide has a particle size of 5 μm, and the indium oxide has a particle size of 70 nm. The zinc mesh is a skein mesh with a thickness of 350 μm and a mesh aperture (the mesh is rhomboid, and the aperture is the side length of the rhombus) of 1000 μm. The thickness of the conductive layer on each side is 35 μm.

[0058] The preparation method of the composite current collector for zinc-based batteries in this embodiment includes the following steps:

[0059] 1) Add 7 parts by weight of SBR and 1 part by weight of CMC to 400 parts by weight of deionized water, stir for 30 minutes to mix evenly to obtain a glue solution. Then add 50 parts by weight of copper powder, 12 parts by weight of tin dioxide powder, 1.5 parts by weight of bismuth oxide and 0.5 parts by weight of indium oxide to the glue solution in sequence, and stir for 90 minutes to obtain a conductive paste.

[0060] 2) Coat the conductive paste onto both surfaces of the zinc mesh and dry at 100°C for 10 hours to obtain the final product.

[0061] Example 6

[0062] The zinc-based battery composite current collector of this embodiment includes a zinc substrate and conductive layers coated on both sides of the zinc substrate. The zinc substrate is a zinc mesh. The conductive layers are composed of the following parts by weight: 50 parts copper powder, 10 parts tin powder, 10 parts tin dioxide powder, 1 part bismuth oxide, 0.5 parts indium oxide, and 11.5 parts binder. The binder is composed of 10 parts SBR and 1.5 parts CMC. The copper powder has a particle size of 400 mesh, the tin powder has a particle size of 45 μm, the tin dioxide has a particle size of 20 μm, the bismuth oxide has a particle size of 5 μm, and the indium oxide has a particle size of 70 nm. The zinc mesh is a skein mesh with a thickness of 350 μm and a mesh aperture (the mesh is rhomboid, and the aperture is the side length of the rhombus) of 1000 μm. The thickness of the conductive layer on each side is 50 μm.

[0063] The preparation method of the composite current collector for zinc-based batteries in this embodiment includes the following steps:

[0064] 1) Add 10 parts by weight of SBR and 1.5 parts by weight of CMC to 400 parts by weight of deionized water and stir for 30 minutes to mix evenly to obtain a glue solution. Then add 50 parts by weight of copper powder, 10 parts by weight of tin powder, 10 parts by weight of tin dioxide powder and 1 part by weight of bismuth oxide to the glue solution in sequence and stir for 90 minutes. Then add 0.5 parts by weight of indium oxide and stir for 10 minutes to obtain a conductive paste.

[0065] 2) Coat the conductive paste onto both surfaces of the zinc mesh and dry at 100°C for 10 hours to obtain the final product.

[0066] Example 7

[0067] The zinc-based battery composite current collector of this embodiment includes a zinc substrate and conductive layers coated on both sides of the zinc substrate. The zinc substrate is a zinc mesh. The conductive layers are composed of the following parts by weight: 50 parts copper powder, 10 parts zinc powder, 3 parts lead powder, 12 parts tin dioxide powder, 1 part bismuth oxide, 0.5 parts indium oxide, 3 parts graphite, and 17 parts binder. The binder consists of 15 parts SBR and 2 parts CMC. The copper powder has a particle size of 400 mesh, the zinc powder has a particle size of 200 mesh, the lead powder has a particle size of 3 μm, the tin dioxide has a particle size of 20 μm, the bismuth oxide has a particle size of 5 μm, and the indium oxide has a particle size of 70 nm. The zinc mesh is a skein mesh with a thickness of 350 μm and a mesh aperture (the mesh is rhomboid, and the aperture is the side length of the rhombus) of 1000 μm. The thickness of the conductive layer on each side is 50 μm.

[0068] The preparation method of the composite current collector for zinc-based batteries in this embodiment includes the following steps:

[0069] 1) Add 15 parts by weight of SBR and 2 parts by weight of CMC to 500 parts by weight of deionized water and stir for 30 minutes to mix evenly to obtain a colloid. Then add 50 parts by weight of copper powder, 10 parts by weight of zinc powder, 3 parts by weight of lead powder, 12 parts by weight of tin dioxide powder and 1 part by weight of bismuth oxide to the colloid in sequence and stir for 90 minutes. Then add 0.5 parts by weight of indium oxide and 3 parts by weight of graphite and stir for 10 minutes to obtain a conductive paste.

[0070] 2) Coat the conductive paste onto both surfaces of the zinc mesh and dry at 100°C for 10 hours to obtain the final product.

[0071] Example 8

[0072] The zinc-based battery composite current collector of this embodiment includes a zinc substrate and conductive layers coated on both sides of the zinc substrate. The zinc substrate is a zinc mesh. The conductive layers are composed of the following parts by weight: 50 parts copper powder, 3 parts lead powder, 1.5 parts bismuth powder, 0.5 parts indium powder, 12 parts tin dioxide powder, 3 parts titanium nitride, 5 parts graphene, and 17 parts binder. The binder consists of 15 parts SBR and 2 parts CMC. The copper powder has a particle size of 400 mesh, the lead powder has a particle size of 3 μm, the bismuth powder has a particle size of 50 nm, the indium powder has a particle size of 60 nm, the tin dioxide has a particle size of 20 μm, and the titanium nitride has a particle size of 1 μm. The zinc mesh is a skein mesh with a thickness of 350 μm and a mesh aperture (the mesh is rhomboid, and the aperture is the side length of the rhombus) of 1000 μm. The thickness of the conductive layer on each side is 50 μm.

[0073] The preparation method of the composite current collector for zinc-based batteries in this embodiment includes the following steps:

[0074] 1) Add 15 parts by weight of SBR and 2 parts by weight of CMC to 500 parts by weight of deionized water and stir for 30 minutes to mix evenly to obtain a glue solution. Then add 50 parts by weight of copper powder, 3 parts by weight of lead powder, 12 parts by weight of tin dioxide powder and 1 part by weight of bismuth oxide to the glue solution in sequence and stir for 90 minutes. Then add 1.5 parts by weight of bismuth powder, 0.5 parts by weight of indium powder, 5 parts by weight of graphene and 3 parts by weight of titanium nitride and stir for 10 minutes to obtain a conductive paste.

[0075] 2) Coat the conductive paste onto both surfaces of the zinc mesh and dry at 100°C for 10 hours to obtain the final product.

[0076] Example 9

[0077] The zinc-based battery composite current collector of this embodiment includes a zinc substrate and a conductive layer coated on both sides of the zinc substrate. The zinc substrate is a zinc mesh. The conductive layer is composed of the following parts by weight: 50 parts copper powder, 10 parts magnesium powder, 3 parts lead powder, 1 part manganese powder, 1 part cadmium powder, 12 parts manganese dioxide powder, 1 part bismuth oxide, 0.5 parts indium oxide, 3 parts graphite, and 17 parts binder. The binder is composed of 15 parts SBR and 2 parts CMC. The copper powder has a particle size of 400 mesh, the magnesium powder has a particle size of 20 nm, the lead powder has a particle size of 3 μm, the manganese powder has a particle size of 1 μm, the cadmium powder has a particle size of 200 mesh, the manganese dioxide has a particle size of 300 mesh, the bismuth oxide has a particle size of 5 μm, and the indium oxide has a particle size of 70 nm. The zinc mesh is a diagonal wire mesh with a thickness of 350 μm. The mesh aperture (the mesh is rhomboid, and the aperture is the side length of the rhombus) is 1000 μm, and the conductive layer on each side is 50 μm thick.

[0078] The preparation method of the composite current collector for zinc-based batteries in this embodiment includes the following steps:

[0079] 1) Add 15 parts by weight of SBR and 2 parts by weight of CMC to 500 parts by weight of deionized water and stir for 30 minutes to mix evenly to obtain a colloid. Then add 50 parts by weight of copper powder, 10 parts by weight of magnesium powder, 3 parts by weight of lead powder, 1 part by weight of cadmium powder, 12 parts by weight of tin dioxide powder and 1 part by weight of bismuth oxide to the colloid in sequence and stir for 90 minutes. Then add 0.5 parts by weight of indium oxide, 1 part by weight of manganese powder and 3 parts by weight of graphite and stir for 10 minutes to obtain a conductive paste.

[0080] 2) Coat the conductive paste onto both surfaces of the zinc mesh and dry at 100°C for 10 hours to obtain the final product.

[0081] Example 10

[0082] The zinc-based battery composite current collector of this embodiment includes a zinc substrate and a conductive layer coated on both sides of the zinc substrate. The zinc substrate is a zinc mesh, and the conductive layer is composed of the following parts by weight: 50 parts copper powder, 3 parts lead powder, 1.5 parts bismuth powder, 0.5 parts indium powder, 12 parts tin dioxide powder, 3 parts titanium nitride, 2 parts calcium titanate, 5 parts graphene, and 17 parts binder. The binder is composed of 15 parts SBR and 2 parts CMC. The copper powder has a particle size of 400 mesh, the lead powder has a particle size of 3 μm, the bismuth powder has a particle size of 50 nm, the indium powder has a particle size of 60 nm, the tin dioxide has a particle size of 20 μm, the titanium nitride has a particle size of 1 μm, and the calcium titanate has a particle size of 100 nm. The zinc mesh is a diagonal wire mesh with a thickness of 350 μm. The mesh aperture (the mesh is rhomboid, and the aperture is the side length of the rhombus) is 1000 μm, and the thickness of the conductive layer on each side is 50 μm.

[0083] The preparation method of the composite current collector for zinc-based batteries in this embodiment includes the following steps:

[0084] 1) Add 15 parts by weight of SBR and 2 parts by weight of CMC to 500 parts by weight of deionized water and stir for 30 minutes to mix evenly to obtain a colloid. Then add 50 parts by weight of copper powder, 3 parts by weight of lead powder, 12 parts by weight of tin dioxide powder and 1 part by weight of bismuth oxide to the colloid in sequence and stir for 90 minutes. Then add 1.5 parts by weight of bismuth powder, 0.5 parts by weight of indium powder, 5 parts by weight of graphene, 3 parts by weight of titanium nitride and 2 parts by weight of calcium titanate and stir for 10 minutes to obtain a conductive paste.

[0085] 2) Coat the conductive paste onto both surfaces of the zinc mesh, dry at 100℃ for 10 hours, remove and roll to obtain the final product.

[0086] Example 11

[0087] The zinc-based battery composite current collector of this embodiment includes a zinc substrate and conductive layers coated on both sides of the zinc substrate. The zinc substrate is a zinc mesh, and the conductive layers are composed of the following parts by weight: 70 parts copper powder, 3 parts lead powder, 1.5 parts bismuth powder, 0.5 parts indium powder, 12 parts tin dioxide powder, 3 parts titanium nitride, 2 parts lithium manganese oxide, 5 parts graphene, and 17 parts binder. The binder is composed of 15 parts SBR and 2 parts CMC. The copper powder has a particle size of 400 mesh, the lead powder has a particle size of 3 μm, the bismuth powder has a particle size of 50 nm, the indium powder has a particle size of 60 nm, the tin dioxide has a particle size of 20 μm, the titanium nitride has a particle size of 1 μm, and the lithium manganese oxide has a particle size of 10 μm. The zinc mesh is a diagonal mesh with a thickness of 350 μm and a mesh aperture (the mesh is rhomboid, and the aperture is the side length of the rhombus) of 1000 μm. The conductive layer on each side has a thickness of 50 μm.

[0088] The preparation method of the composite current collector for zinc-based batteries in this embodiment includes the following steps:

[0089] 1) Add 15 parts by weight of SBR and 2 parts by weight of CMC to 500 parts by weight of deionized water and stir for 30 minutes to mix evenly to obtain a colloid. Then add 70 parts by weight of copper powder, 3 parts by weight of lead powder, 12 parts by weight of tin dioxide powder and 1 part by weight of bismuth oxide to the colloid in sequence and stir for 90 minutes. Then add 1.5 parts by weight of bismuth powder, 0.5 parts by weight of indium powder, 5 parts by weight of graphene, 3 parts by weight of titanium nitride and 2 parts by weight of lithium manganese oxide and stir for 10 minutes to obtain a conductive paste.

[0090] 2) Coat the conductive paste onto both surfaces of the zinc mesh, dry at 100℃ for 10 hours, remove and roll to obtain the final product.

[0091] Example 12

[0092] Zinc-nickel batteries were prepared using the composite current collector from Examples 1-11 as the negative electrode current collector. The zinc-nickel battery includes a positive electrode, a negative electrode, a separator, and an electrolyte. The negative electrode includes a negative electrode current collector and a negative electrode active material layer coated on the surface of the negative electrode current collector; the negative electrode current collector is the aforementioned composite current collector. The positive electrode includes a positive electrode current collector and a positive electrode active material layer, which comprises nickel hydroxide, conductive carbon black, polytetrafluoroethylene, and cobalt oxide in a mass ratio of 88:6:0.5:5.5. The negative electrode active material layer comprises zinc oxide (ZnO), zinc (Zn), indium oxide (In₂O₃), bismuth oxide (Bi₂O₃), PTFE binder, thickener, conductive carbon fiber, potassium fluoride (KF), polypropylene (PP) fiber, sodium polyacrylate dispersant (Haichuan 5040), glycerol, and phosphate in a mass ratio of 48.63:35.58:0.36:2.37:5.93:0.38:0.59:0.24:0.59:0.59:2.037:2.37.

[0093] AA cylindrical zinc-nickel batteries were prepared according to existing technologies and numbered 1-11#.

[0094] Test case

[0095] (1) Physical property testing

[0096] Take the zinc-based battery composite current collectors from Examples 1-11 and observe their surface quality. The surface of the current collector without rolling is flat and uniform, while the surface of the current collector after rolling is flat and smooth with faint traces of zinc mesh holes.

[0097] (2) Open circuit voltage test

[0098] The open-circuit voltages of batteries #1-#11 were tested, as shown in the table below:

[0099] Table 1 Open circuit voltage of batteries #1-#11

[0100]

[0101]

[0102] As can be seen from the table above, the zinc-nickel battery prepared by this invention has a high open-circuit voltage, and the composite current collector for the zinc-based battery of this invention will not reduce the negative electrode potential.

[0103] (3) Cyclic performance

[0104] The above-mentioned zinc-nickel batteries #1-#4 were tested for their cycle performance at a charge-discharge rate of 0.5C. The first discharge curve of zinc-nickel battery #1 is shown below. Figure 1 As shown, the cycle performance test results of zinc-nickel batteries #1-#4 are as follows: Figure 2 As shown.

[0105] Depend on Figure 2 It is known that the zinc-nickel battery using the composite current collector of the zinc-based battery of the present invention exhibits slower capacity decay in the first 100 cycles during charge-discharge cycles, slightly faster capacity decay in the 100-200 cycles, and then tends to stabilize.

Claims

1. A composite current collector for zinc-based batteries, characterized in that, The device includes a zinc substrate and a conductive layer attached to the zinc substrate, wherein the zinc substrate is zinc, a zinc alloy, or galvanized metal; the conductive layer includes metal powder and a binder, wherein the metal powder is at least one selected from copper powder, tin powder, magnesium powder, calcium powder, zinc powder, titanium powder, manganese powder, indium powder, lead powder, cadmium powder, palladium powder, bismuth powder, tungsten powder, and vanadium powder. The mass ratio of the metal powder to the binder is 50-95:5-35; The conductive layer further includes a conductive agent, which is at least one selected from graphite, acetylene black, graphene, carbon fiber, and carbon nanotubes; The conductive layer further includes an oxide, wherein the oxide is at least one selected from tin dioxide, zinc oxide, manganese dioxide, bismuth oxide, and indium oxide; The conductive layer further includes a nitride, which is any one of calcium nitride, titanium nitride, magnesium nitride, and strontium nitride; the conductive layer further includes a reinforcing agent, which is at least one of calcium titanate and lithium manganate. The mass ratio of metal powder to conductive agent is 50-70:10-20; The mass ratio of metal powder to oxide is 50-70:8-50; The mass ratio of metal powder to nitride is 50-70:3-8; The mass ratio of metal powder to reinforcing agent is 50-70:0.5-1.

5.

2. The composite current collector for zinc-based batteries according to claim 1, characterized in that, The particle size of the metal powder is 200-2000 mesh.

3. The composite current collector for zinc-based batteries according to claim 1, characterized in that, The ratio of the thickness of the zinc substrate to the thickness of the conductive layer is 300-500:30-80.

4. A negative electrode sheet for a zinc-based battery, comprising a negative electrode current collector and a negative electrode material layer coated on the negative electrode current collector, characterized in that, The negative electrode current collector is the composite current collector for zinc-based batteries as described in claim 1.

5. A zinc-based battery, comprising a positive electrode and a negative electrode, characterized in that, The negative electrode is the negative electrode for zinc-based batteries as described in claim 4.

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