A zinc-nickel battery

Abstract

The application discloses a zinc-nickel battery. The zinc-nickel battery comprises an alkaline electrolyte containing an additive, a positive electrode and a negative electrode; the additive is selected from a substance with the structure of formula I: wherein R is selected from methyl and / or -NH-methyl, and at least one R in formula I is methyl; the mass content of the additive in the alkaline electrolyte containing the additive is 1-10 wt%.

Description

Technical Field

[0001] This application relates to a zinc-nickel battery, belonging to the field of zinc-nickel batteries. Background Technology

[0002] With the world facing an unprecedented environmental and energy crisis, clean and renewable energy has become crucial. This surge in demand for green electricity has driven the development of grid-scale energy storage systems. Currently, non-aqueous lithium-ion batteries dominate the market for grid-scale electrochemical energy storage devices, but they suffer from problems such as low power density, flammability, environmentally unfriendly organic electrolytes, and high cost. In contrast, aqueous rechargeable batteries have attracted widespread attention in the energy storage field due to their high safety and low cost. Among the many aqueous rechargeable batteries, zinc-nickel batteries have advantages such as high output voltage (≈1.8V), high energy density, and good safety, which make it possible to develop high-energy, safe, and inexpensive energy storage devices. However, during charging and discharging, the high solubility of zinc oxide, a discharge product, in alkaline electrolytes leads to changes in the surface shape of the zinc negative electrode. At the same time, zinc is thermodynamically unstable in aqueous media, and the occurrence of hydrogen evolution side reactions consumes electrolytes, thereby reducing battery performance. Therefore, the preparation of highly stable electrolyte additives and negative electrode materials is an essential path to promote the commercialization of zinc-nickel batteries, and is also of great significance for the efficient utilization of clean energy and the construction of a new energy society. Summary of the Invention

[0003] The purpose of this invention is to address the problem of low cycle performance in existing aqueous zinc-nickel battery systems. It provides a method for preparing electrolyte additives and negative electrode materials for zinc-nickel batteries with high cycle stability. By adding additives to the electrolyte and preparing electrode sheets using the method of this application, the occurrence of hydrogen evolution side reactions is reduced and the changes in the shape of the zinc anode are mitigated, thereby achieving a highly stable zinc-nickel battery.

[0004] According to one aspect of this application, a zinc-nickel battery is provided, the zinc-nickel battery comprising an alkaline electrolyte containing additives, a positive electrode, and a negative electrode;

[0005] The additive is selected from substances having the structure of Formula I:

[0006]

[0007] Wherein, R is selected from methyl and / or -NH-methyl, and at least one of R in Formula I is methyl;

[0008] In the alkaline electrolyte containing additives, the mass content of the additives is 1 to 10 wt%.

[0009] The negative electrode is obtained by grinding negative electrode material, adding ethanol during the grinding process, rolling it into a thin sheet, and then cutting it.

[0010] The negative electrode material contains zinc oxide, a conductive agent, and a binder.

[0011] The conductive agent is selected from at least one of acetylene black and Kochin black;

[0012] The adhesive is selected from polytetrafluoroethylene.

[0013] In the negative electrode material, the zinc oxide content is 70-80 wt%;

[0014] In the negative electrode material, the mass content of the conductive agent is 8-10 wt%.

[0015] The negative electrode material contains zinc powder;

[0016] In the negative electrode material, the zinc powder has a mass content of 4-6 wt%.

[0017] The negative electrode material contains auxiliary metal oxides;

[0018] The auxiliary metal oxide is selected from at least one of aluminum oxide, bismuth oxide, yttrium oxide, and indium oxide;

[0019] In the electrode material, the mass content of the other metal oxides is 0.1 to 1 wt%.

[0020] Specifically, the negative electrode is obtained through the following steps:

[0021] Taking the mass ratio of ZnO, Zn, Bi2O3, Al2O3, acetylene black, and PTFE as an example, which is 70:5:6:1:10:8.

[0022] (1) Weigh a total of 200mg. First, mix 140mg of ZnO, 10mg of Zn, 12mg of Bi2O3, 2mg of Al2O3 and 20mg of acetylene black together and grind for 20min.

[0023] (2) Add 16 mg of 60 wt% PTFE emulsion to the mixed powder in (1) and crush it continuously with a spoon until the mixed powder sticks together.

[0024] (3) Add ethanol to the mixture in (2), roll it continuously with a large glass rod, and cut out a piece with a diameter of 10 mm.

[0025] (4) Immerse the copper mesh in the tin plating solution for 2 minutes to obtain a copper mesh with uniform tin plating on the surface, and cut out tin-plated copper sheets with a diameter of 12 mm.

[0026] (5) Press the electrode sheet from (3) onto the tin-plated copper mesh obtained in (4) using a tablet press to obtain the finished negative electrode sheet.

[0027] The alkaline electrolyte containing additives contains alkaline substances.

[0028] The alkaline substance is selected from at least one of sodium hydroxide and potassium hydroxide.

[0029] The concentration of the alkaline substance in the alkaline electrolyte containing additives is 1–6 M.

[0030] The beneficial effects that this application can produce include:

[0031] 1) The additive provided in this application has the function of regulating the solvation structure of zinc.

[0032] 2) The additives provided in this application have the effect of reducing negative electrode corrosion and HER.

[0033] 3) The negative electrode preparation method provided in this application has the function of adjustable loading and preparation of high loading electrodes.

[0034] 4) The additive provided in this application has the function of inhibiting zinc oxide dissolution and HER. Attached Figure Description

[0035] Figure 1 This is a discharge specific capacity-cycle diagram of Example 1 and Comparative Example 1 of this application.

[0036] Figure 2 The diagram shows the discharge specific capacity and charge / discharge efficiency of Example 2 and Comparative Example 2 of this application. Detailed Implementation

[0037] The present application is described in detail below with reference to the embodiments, but the present application is not limited to these embodiments.

[0038] Unless otherwise specified, all raw materials used in the embodiments of this application were purchased through commercial channels.

[0039] Example 1

[0040] 5 wt% SO2(CH3)2 was added to a 6 M potassium hydroxide solution and stirred for 30 min to obtain the electrolyte.

[0041] For the negative electrode material, nano-zinc oxide powder was soaked in a 1 mol / L InCl3 solution and stirred for 5 h. After centrifugation, the precipitate was washed three times with deionized water and dried at 60 °C for 24 h. The obtained nano-zinc oxide, zinc powder, bismuth trioxide, aluminum oxide, acetylene black, and polytetrafluoroethylene were ground in a ratio of 70:5:6:1:10:8 for 30 min, and ethanol was continuously added to the powder to form a paste. The paste was rolled into thin sheets and cut into electrode sheets with a diameter of 10 mm.

[0042] Aqueous zinc-nickel battery assembly:

[0043] The synthesized negative electrode was used as the negative electrode sheet of the battery, GF-D was used as the separator, 6M potassium hydroxide containing 5wt% SO2(CH3)2 was used as the electrolyte, and Chaowei positive electrode material was used as the positive electrode sheet. The battery was assembled into a coin cell under a pressure of 1.2T and constant current charge and discharge test was performed using the Land battery test system.

[0044] Example 2

[0045] 5 wt% SO2NH(CH3)2 was added to a 6 M potassium hydroxide solution and stirred for 30 min to obtain the electrolyte.

[0046] For the negative electrode material, nano-zinc oxide powder was soaked in a 1 mol / L InCl3 solution and stirred for 5 h. After centrifugation, the precipitate was washed three times with deionized water and dried at 60 °C for 24 h. The obtained nano-zinc oxide, zinc powder, bismuth trioxide, aluminum trioxide, acetylene black, and polytetrafluoroethylene were ground in a ratio of 70:5:6:1:10:8 for 30 min, and ethanol was continuously added to the powder to form a paste.

[0047] Assembling aqueous zinc-nickel cylindrical solar cells:

[0048] The synthesized negative electrode was used as the negative electrode sheet of the battery, PP was used as the separator, 6M potassium hydroxide containing 5wt% SO2NH(CH3)2 was used as the electrolyte, and commercially available Chaowei positive electrode material was used as the positive electrode. The battery was assembled into an alkaline cylindrical battery and constant current charge-discharge test was performed using the Land battery testing system.

[0049] Comparative Example 1

[0050] Compared to Example 1, a solution containing only 6M potassium hydroxide was also prepared and stirred for 30 min as an electrolyte.

[0051] For the negative electrode material, nano-zinc oxide powder was soaked in a 1 mol / L InCl3 solution and stirred for 5 h. After centrifugation, the precipitate was washed three times with deionized water and dried at 60 °C for 24 h. The obtained nano-zinc oxide, zinc powder, bismuth trioxide, aluminum oxide, acetylene black, and polytetrafluoroethylene were ground in a ratio of 70:5:6:1:10:8 for 30 min, and ethanol was continuously added to the powder to form a paste. The paste was rolled into thin sheets and cut into electrode sheets with a diameter of 10 mm.

[0052] Figure 1 This is a discharge specific capacity-cycle diagram of Example 1 and Comparative Example 1 of this application.

[0053] from Figure 1As can be seen, the specific capacity of the battery increases significantly and its lifespan is extended considerably after the addition of SO2(CH3)2. This is attributed to the high polarity of the oxygen in SO2(CH3)2, which allows it to be incorporated into the solvation structure of zinc oxide ions, thereby reducing the dissolution of the negative electrode and the occurrence of the HER side reaction.

[0054] Comparative Example 2

[0055] Compared to Example 2, an electrolyte containing the Chaowei commercial zinc-nickel alkaline battery was used.

[0056] For the negative electrode material, nano-zinc oxide powder was soaked in a 1 mol / L InCl3 solution and stirred for 5 h. After centrifugation, the precipitate was washed three times with deionized water and dried at 60 °C for 24 h. The obtained nano-zinc oxide, zinc powder, bismuth trioxide, aluminum trioxide, acetylene black, and polytetrafluoroethylene were ground in a ratio of 70:5:6:1:10:8 for 30 min, and ethanol was continuously added to the powder to form a paste.

[0057] Figure 2 The diagram shows the discharge specific capacity and charge / discharge efficiency of Example 2 and Comparative Example 2 of this application.

[0058] from Figure 2 As can be seen, the battery life is significantly extended and the coulombic efficiency is significantly increased after adding SO2NH(CH3)2. This is attributed to the high polarity of the oxygen in SO2NH(CH3)2, which allows it to be incorporated into the solvation structure of zinc oxide ions, thereby reducing the dissolution of the negative electrode and the occurrence of the HER side reaction.

[0059] The above description is merely a few embodiments of this application and is not intended to limit this application in any way. Although this application discloses preferred embodiments as described above, it is not intended to limit this application. Any changes or modifications made by those skilled in the art without departing from the scope of the technical solution of this application using the disclosed technical content are equivalent to equivalent implementation cases and fall within the scope of the technical solution.

Claims

1. A zinc-nickel battery, characterized in that, The zinc-nickel battery includes an alkaline electrolyte containing additives, a positive electrode, and a negative electrode; The additive is selected from substances having the structure of Formula I: Equation I; Wherein, R is selected from methyl and / or -NH-methyl, and at least one of R in Formula I is methyl; In the alkaline electrolyte containing additives, the mass content of the additives is 1~10wt%; The negative electrode is obtained by grinding negative electrode material, adding ethanol during the grinding process, rolling it into a thin sheet, and cutting it. The negative electrode material contains zinc oxide, a conductive agent, and a binder.

2. The zinc-nickel battery according to claim 1, characterized in that, The conductive agent is selected from at least one of acetylene black and Kochin black; The adhesive is selected from polytetrafluoroethylene.

3. The zinc-nickel battery according to claim 2, characterized in that, In the negative electrode material, the zinc oxide content is 70-80 wt%; In the negative electrode material, the mass content of the conductive agent is 8~10 wt%.

4. The zinc-nickel battery according to claim 2, characterized in that, The negative electrode material contains zinc powder; In the negative electrode material, the zinc powder has a mass content of 4-6 wt%.

5. The zinc-nickel battery according to claim 2, characterized in that, The negative electrode material contains auxiliary metal oxides; The auxiliary metal oxide is selected from at least one of aluminum oxide, bismuth oxide, yttrium oxide, and indium oxide; In the negative electrode material, the mass content of the auxiliary metal oxide is 0.1~1 wt%.

6. The zinc-nickel battery according to claim 1, characterized in that, The alkaline electrolyte containing additives contains alkaline substances.

7. The zinc-nickel battery according to claim 6, characterized in that, The alkaline substance is selected from at least one of sodium hydroxide and potassium hydroxide.

8. The zinc-nickel battery according to claim 6, characterized in that, The concentration of the alkaline substance in the alkaline electrolyte containing additives is 1~6 M.

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