Application of sulfonated polyetheretherketone as binder in zinc-nickel battery negative electrode material

Abstract

The invention discloses application of sulfonated polyetheretherketone as a binder in a zinc-nickel battery negative electrode material. The zinc-nickel battery negative electrode material comprises negative electrode raw material powder and the binder, the negative electrode raw material powder comprises zinc oxide, zinc powder, carbon nanotubes and a hydrogen evolution inhibition additive, and the binder is sulfonated polyetheretherketone. According to the application, the negative electrode slurry coated on the current collector is good in stability and not easy to fall off, an electrode coating process commonly used by a lithium battery can be used, and the prepared negative electrode is relatively good in uniformity and controllable in active substance carrying capacity.

Description

Technical Field

[0001] The present application provides an application of sulfonated polyether ether ketone as a binder in the negative electrode material of a zinc-nickel battery, belonging to the technical field of energy storage. Background Art

[0002] Due to its characteristics such as high safety, high working voltage, high energy density, high power density, and wide working temperature, the zinc-nickel secondary battery has good application prospects in the fields of power tools and low-speed electric vehicles. However, the short cycle life of existing zinc-nickel batteries severely restricts their rapid commercialization process. The preparation of the negative electrode of the zinc-nickel battery is one of the key factors affecting the performance of the zinc-nickel battery.

[0003] In the preparation process of the negative electrode of traditional nickel-zinc batteries, PTFE binder is used. After preparing zinc oxide, zinc powder, conductive agent, and additives into a dough-like mass, it is compounded with the negative electrode current collector. This method cannot utilize the slurry continuous doctor blade coating or roll transfer coating process currently used in lithium-ion batteries. Summary of the Invention

[0004] To solve the above technical problems, the present application provides a preparation method of a negative electrode material for a zinc-nickel battery, the negative electrode material for a zinc-nickel battery, and a zinc-nickel battery. The method can make the negative electrode slurry coated on the current collector have good stability and is not easy to fall off. It can use the common electrode coating process in lithium batteries, and the prepared negative electrode has good uniformity and the active material loading can be controlled.

[0005] To achieve the above invention purpose, the present application provides the following technical solutions:

[0006] An application of sulfonated polyether ether ketone as a binder in the negative electrode material of a zinc-nickel battery, the negative electrode material of the zinc-nickel battery including negative electrode raw material powder and a binder;

[0007] The negative electrode raw material powder includes zinc oxide, zinc powder, carbon nanotubes, and a hydrogen evolution inhibition additive, and the binder is sulfonated polyether ether ketone.

[0008] Optionally, the content of the binder in the negative electrode material of the zinc-nickel battery is 1-10 wt%.

[0009] Optionally, the content of the binder in the negative electrode material of the zinc-nickel battery is selected from any value or the range value between any two of 1 wt%, 2 wt%, 3 wt%, 4 wt%, 5 wt%, 6 wt%, 7 wt%, 8 wt%, 9 wt%, 10 wt%.

[0010] Optionally, the weight ratio of the binder to carbon nanotubes, zinc oxide, zinc powder, and hydrogen evolution inhibition additive is 1:(0.5-1.5):(9-11):(6-8):(0.2-0.4).

[0011] Optionally, the hydrogen evolution inhibition additive is selected from at least one of indium hydroxide, indium oxide, and bismuth oxide.

[0012] Optionally, the method for preparing the negative electrode material of the zinc-nickel battery includes the following steps:

[0013] S1. Obtain a negative electrode raw material powder mixture;

[0014] S2. Vacuum stir the mixture containing the negative electrode raw material powder, binder, and solvent to obtain a negative electrode slurry;

[0015] S3. Coat the negative electrode slurry on a current collector, and successively perform drying and rolling to obtain the negative electrode of the zinc-nickel battery.

[0016] Optionally, in step S3, the coating is performed by one of the slurry continuous knife coating or roll transfer coating methods of lithium-ion batteries in the prior art;

[0017] Optionally, in step S2, the solvent is selected from at least one of dimethylformamide, dimethylacetamide, and N-methylpyrrolidone;

[0018] Optionally, in step S3, the total solid content of the negative electrode raw material powder and the binder in the slurry is 50-80%.

[0019] Optionally, step S2 includes:

[0020] S21. Mix and stir the binder and the solvent to obtain a mixed solution;

[0021] S22. Add the negative electrode raw material powder to the mixed solution and vacuum stir to obtain a negative electrode slurry.

[0022] Optionally, in step S21, the rotation speed of the vacuum stirring is 30-150 rpm, and the stirring time is 0.5-5 h.

[0023] Optionally, in step S22, the rotation speed of the vacuum stirring is 60-100 rpm, and the stirring time is 1.5-4 h.

[0024] Optionally, in step S3, the current collector is selected from foil materials of at least one metal among zinc, copper, and tin.

[0025] Optionally, in step S3, the drying temperature is 30-80 °C, and the drying time is 1-8 h.

[0026] Compared with the prior art, the present application has the following beneficial effects:

[0027] (1) The application of sulfonated polyether ether ketone provided by this application as a binder in the negative electrode material of zinc-nickel batteries, and the preparation method of the negative electrode of zinc-nickel batteries adopted, can use the currently existing mature fluid slurry coating process, which has a simple process, strong operability, and good electrode uniformity.

[0028] (2) The negative electrode material of zinc-nickel batteries provided by this application adopts a suitable binder, which can make the negative electrode slurry have a strong bonding force with the current collector, not easy to fall off, and the density of the active material is high; the solid content of the sample is high, which is convenient for preparing a negative electrode with a large load. Brief Description of the Drawings

[0029] In order to more clearly illustrate the technical solutions of the embodiments of this application, the drawings required to be used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application, and therefore should not be regarded as limiting the scope. For those of ordinary skill in the art, without creative efforts, other related drawings can also be obtained based on these drawings.

[0030] Figure 1 It is the performance diagram of the cylindrical battery of the zinc-nickel battery prepared in Example 1 of this application. Detailed Embodiments

[0031] The following will further elaborate on this application in combination with specific embodiments. The following descriptions are only several embodiments of this application and do not impose any form of limitation on this application. Although this application is disclosed in the following preferred embodiments, it is not intended to limit this application. Any person skilled in the art, without departing from the scope of the technical solutions of this application, making some changes or modifications using the technical content disclosed above is equivalent to equivalent implementation cases and all belong to the scope of the technical solutions.

[0032] Unless otherwise specified, the raw materials in the embodiments of this application are all purchased through commercial channels and used directly without any special treatment.

[0033] Unless otherwise specified, the analysis methods in the embodiments all adopt the conventional settings and conventional analysis methods of instruments or equipment.

[0034] Example 1

[0035] The negative electrode uses zinc foil as the current collector, and the slurry coated on the zinc foil has the following composition (by mass ratio): zinc oxide (53%), zinc powder (35%), carbon nanotubes (5%), indium hydroxide (2%) and sulfonated polyether ether ketone (5%). Dimethylacetamide is used as the solvent, and the solid content is 70%. The specific preparation steps of the negative electrode material are as follows:

[0036] 1. Mix the zinc oxide, zinc powder, carbon nanotubes and indium hydroxide powders evenly;

[0037] 2. Add sulfonated polyether ether ketone to dimethylacetamide and stir at a stirring speed of 100 rpm for 120 min;

[0038] 3. Add the mixed powder to the above-mentioned dimethylacetamide containing sulfonated polyether ether ketone and stir under vacuum at a stirring speed of 80 rpm for 3 h to obtain the negative electrode slurry;

[0039] 4. Coat the negative electrode slurry on a 50-μm zinc foil, dry it at 40 °C for 5 h, and then roll it to obtain a zinc-nickel battery negative electrode with a thickness of 0.2 mm. The loading of the negative electrode material is about 37.6 mg / cm 2 .

[0040] Cut the negative electrode into a rectangle with a length of 32 cm and a width of 5.5 cm, and use it for a cylindrical 18650 zinc-nickel battery. The battery also includes a nickel positive electrode with double-sided coated nickel hydroxide, a separator, an alkaline electrolyte (4M potassium hydroxide + 2M potassium fluoride + 1M potassium carbonate), a cylindrical battery case, and a battery case cover.

[0041] The cylindrical battery is charged and discharged in a constant current of 1 A. The discharge cut-off voltage is 1.0 V, the Coulomb efficiency is greater than 97%, the energy efficiency is greater than 87%, the discharge capacity is greater than 1 Ah, and it can be cycled more than 80 times.

[0042] Comparative Example 1

[0043] The preparation method of the negative electrode material is similar to that of Example 1, except that the binder used is replaced by a PTFE binder. After mixing the powder with the solvent and adding PTFE, the raw material will become dough-like and cannot be used to prepare the electrode by the existing common electrode coating process for lithium batteries.

[0044] The above are only several embodiments of the present application and do not impose any form of limitation on the present application. Although the present application is disclosed as above with preferred embodiments, it is not intended to limit the present application. Any person skilled in the art, without departing from the technical solution of the present application, makes some changes or modifications using the disclosed technical content, which are equivalent to equivalent implementation cases and all fall within the scope of the technical solution.

Claims

1. Application of sulfonated polyether ether ketone as a binder in the negative electrode material of zinc-nickel batteries, characterized in that, The negative electrode material of the zinc-nickel battery includes a negative electrode raw material powder and a binder; The negative electrode raw material powder includes zinc oxide, zinc powder, carbon nanotubes and a hydrogen evolution inhibition additive; The binder is sulfonated polyether ether ketone.

2. The application according to claim 1, characterized in that, The content of the binder in the negative electrode material of the zinc-nickel battery is 1-10 wt%.

3. The application according to claim 1, characterized in that, The weight ratio of the binder to carbon nanotubes, zinc oxide, zinc powder, and hydrogen evolution inhibition additive is 1:(0.5-1.5):(9-11):(6-8):(0.2-0.4).

4. The application according to claim 1, characterized in that, The hydrogen evolution inhibition additive is selected from at least one of indium hydroxide, indium oxide, and bismuth oxide.

5. The application according to claim 1, characterized in that, The preparation method of the negative electrode material of the zinc-nickel battery includes the following steps: S1. Obtain a mixture of negative electrode raw material powders; S2. Mix the mixture containing the negative electrode raw material powder, binder, and solvent, and stir under vacuum to obtain a negative electrode slurry; S3. Coating the negative electrode slurry on a current collector, and drying and rolling it in sequence to obtain the negative electrode of the zinc-nickel battery.

6. The application according to claim 5, characterized in that, In step S3, the coating is carried out by one of the slurry continuous doctor blade coating or roll transfer coating methods of lithium-ion batteries in the prior art.

7. The application according to claim 5, characterized in that, In step S2, the solvent is selected from at least one of dimethylformamide, dimethylacetamide, and N-methylpyrrolidone; Preferably, in step S3, the total solid content of the negative electrode raw material powder and the binder in the slurry is 50-80%.

8. The application according to claim 5, characterized in that, Step S2 includes: S21. Mix and stir the binder and the solvent to obtain a mixed solution; S22. Add the negative electrode raw material powder to the mixed solution and stir under vacuum to obtain a negative electrode slurry.

9. The application according to claim 8, characterized in that, In step S21, the rotation speed of the vacuum stirring is 30-150 rpm, and the stirring time is 0.5-5 h; Preferably, in step S22, the rotation speed of the vacuum stirring is 60-100 rpm, and the stirring time is 1.5-4 h.

10. The application according to claim 5, characterized in that, In step S3, the current collector is selected from foil materials of at least one metal among zinc, copper, and tin.

Images