Preparation method of zinc ion battery gel
By forming an interpenetrating network structure with sodium alginate and acrylamide, and combining it with ZIF8 nanoparticles, the mechanical strength and ionic conductivity issues of the gel electrolyte in zinc-ion batteries were solved, achieving high mechanical strength, good liquid retention capacity, and long cycle life of the battery.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-29
- Publication Date
- 2026-03-24
AI Technical Summary
Existing zinc-ion battery gel electrolytes suffer from insufficient mechanical strength, low ionic conductivity, and poor compatibility with the electrode interface, which affect the battery's cycle life and safety.
Sodium alginate and acrylamide are used to form an interpenetrating double network structure, which is combined with ZIF8 nanoparticles to improve the mechanical strength and liquid retention capacity of the gel. The regular pore structure of ZIF8 also enhances the ionic conductivity and inhibits dendrite growth.
It significantly improves the mechanical strength and liquid retention capacity of zinc-ion batteries, extends battery cycle life, enhances ionic conductivity, suppresses dendrite growth, and improves battery safety and stability.
Smart Images
Figure CN121726567A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of battery gel preparation technology, and in particular to a method for preparing zinc-ion battery gel. Background Technology
[0002] Traditional liquid electrolytes suffer from problems such as leakage and dendrite growth, which limit the cycle life and safety performance of batteries. Gel electrolytes, as a quasi-solid electrolyte, can effectively suppress dendrite growth and improve battery safety. Rechargeable aqueous zinc-ion batteries are attracting increasing attention due to their advantages such as non-toxicity, relative safety, and low cost. Hydrogels combine the transport and diffusion capabilities of liquids with the cohesive properties of solids. Gel polymer electrolytes are also referred to as semi-solid electrolytes in many reports. They can avoid the leakage problem of liquid electrolytes by reducing the free water content, while maintaining high ionic conductivity.
[0003] Currently, common zinc-ion battery gel electrolytes mainly include polyvinyl alcohol (PVA) and polyacrylic acid (PAA) systems. However, these materials suffer from insufficient mechanical strength, low ionic conductivity, and poor compatibility with the electrode interface. Sodium alginate (SA), as a natural polymer material, has good biocompatibility and film-forming properties, but its mechanical properties are poor when used alone. Acrylamide (AM) polymers have high water absorption and flexibility, but insufficient electrochemical stability.
[0004] How to effectively improve the mechanical strength and liquid retention capacity of gels, and extend battery cycle life while improving ionic conductivity, has become a technical problem that needs to be solved.
[0005] In conclusion, the existing technology obviously has inconveniences and defects in practical use, so it is necessary to improve it. Summary of the Invention
[0006] To address the aforementioned deficiencies, the present invention aims to provide a method for preparing zinc-ion battery gel, which can effectively improve the mechanical strength and liquid retention capacity of the gel, and can extend the battery cycle life while improving ionic conductivity.
[0007] To achieve the above objectives, the present invention provides a method for preparing zinc-ion battery gel, comprising the following steps: S1. Add sodium alginate to deionized water and stir to obtain SA solution.
[0008] S2. Add acrylamide to deionized water and stir to obtain AM solution.
[0009] S3. Mix SA solution, AM solution and ZIF8, add initiator and crosslinking agent, stir and pour into mold and dry to obtain zinc ion battery gel.
[0010] According to the preparation method of zinc-ion battery gel of the present invention, the sodium alginate has a mass concentration of 1~6wt%, the stirring time is 2~6 hours, the acrylamide has a mass concentration of 10~40wt%, and the stirring time is 2~5 hours.
[0011] According to the method for preparing zinc-ion battery gel of the present invention, the mold in S3 is 0.5~2mm thick.
[0012] According to the method for preparing zinc-ion battery gel of the present invention, the initiator is potassium persulfate and the crosslinking agent is N,N'-methylenebisacrylamide.
[0013] According to the method for preparing zinc-ion battery gel of the present invention, the initiator is at least one of potassium persulfate, ammonium persulfate or azobisisobutyronitrile, and the amount added is 1% to 3% of the mass of acrylamide.
[0014] According to the preparation method of zinc-ion battery gel of the present invention, the crosslinking agent is at least one of N,N'-methylenebisacrylamide, ethylene glycol dimethacrylate or polyethylene glycol diacrylate, and the amount added is 0.05% to 0.2% of the mass of acrylamide.
[0015] According to the preparation method of zinc-ion battery gel of the present invention, the stirring time in S1 is 4 hours, the stirring time in S2 is 3 hours, the mixing time in S3 is 1 hour, and the stirring time is 30 minutes.
[0016] The method for preparing zinc-ion battery gel according to claim 4 is characterized in that, in step S3, the temperature of the drying oven is 50°C and the drying time is 20 min.
[0017] The present invention also provides a composite gel electrolyte comprising a sodium alginate network, a polyacrylamide network, and ZIF8 nanoparticles dispersed in the dual network.
[0018] The present invention also provides a zinc-ion battery comprising the composite gel electrolyte as an electrolyte or a separator.
[0019] The purpose of this invention is to provide a method for preparing a zinc-ion battery gel. This method utilizes an interpenetrating double network structure formed by sodium alginate and polyacrylamide, combining the excellent film-forming properties of sodium alginate with the high water absorption of polyacrylamide, thereby improving the gel's mechanical strength and liquid retention capacity. The introduction of ZIF8 nanoparticles not only enhances the gel's mechanical properties, but their regular pore structure also provides a rapid channel for zinc ion transport, improving ionic conductivity. Furthermore, the zinc metal centers in ZIF8 exhibit a common ion effect with zinc ions in the electrolyte, which can homogenize the zinc ion flow, inhibit dendrite growth, and extend the battery's cycle life.
[0020] In summary, the beneficial effects of the present invention are: it can effectively improve the mechanical strength and liquid retention capacity of the gel, and can extend the battery cycle life while improving the ionic conductivity. Attached Figure Description
[0021] Figure 1 This is a test diagram of AM5 of the present invention; Detailed Implementation
[0022] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.
[0023] This invention provides a method for preparing zinc-ion battery gel, comprising the following steps: S1. Add sodium alginate to deionized water and stir to obtain SA solution.
[0024] S2. Add acrylamide to deionized water and stir to obtain AM solution.
[0025] S3. Mix SA solution, AM solution and ZIF8 (zeolite imidazole ester skeleton-8, which enhances the mechanical properties and water absorption of hydrogel), add initiator and crosslinking agent, stir, pour into mold and dry to obtain zinc ion battery gel.
[0026] Specifically, the mass concentration of sodium alginate is 1~6wt%, the stirring time is 2~6 hours, and the mass concentration of acrylamide is 10~40wt%, the stirring time is 2~5 hours.
[0027] Specifically, the volume ratio of sodium alginate solution to acrylamide solution is 1:1~3, and the amount of ZIF8 added is 0.5~5wt% of the total gel mass.
[0028] Specifically, the mold in S3 is 0.5~2mm thick, preferably 1mm, and the oven temperature is 50℃ and the drying time is 20min.
[0029] Furthermore, the stirring time in S1 is 4 hours, the stirring time in S2 is 3 hours, the mixing time in S3 is 1 hour, and the stirring time is 30 minutes.
[0030] Preferably, the initiator is one or more of potassium persulfate, ammonium persulfate, or azobisisobutyronitrile, and the amount added is 1% to 3% of the mass of acrylamide.
[0031] Preferably, the crosslinking agent is one or more of N,N'-methylenebisacrylamide, ethylene glycol dimethacrylate, or polyethylene glycol diacrylate, and the amount added is 0.05% to 0.2% of the mass of acrylamide.
[0032] To verify the above method, the present invention provides the following embodiments: Example 1
[0033] Add 1g of sodium alginate to 50mL of deionized water and stir for 4h to obtain SA solution. Then add 40g of acrylamide to 100mL of deionized water and stir for 3h to obtain AM solution. Stir SA solution, AM solution and 0.5g of ZIF8 for 1h, add 0.75g of APS (potassium persulfate) and 0.04g of MBA (N,N'-methylenebisacrylamide) and stir for another 30min. Pour the obtained solution into a 1mm thick mold and place it in a 50℃ oven for 20min to obtain the corresponding hydrogel, denoted as AM1.
[0034] Example 2
[0035] Add 2g of sodium alginate to 50mL of deionized water and stir for 4h to obtain SA solution; then add 40g of acrylamide to 100mL of deionized water and stir for 3h to obtain AM solution. Stir SA solution, AM solution and 0.5g of ZIF8 for 1h, add 0.75g of APS and 0.04g of MBA and stir for another 30min. Pour the resulting solution into a 1mm thick mold and place it in a 50℃ oven for 20min to obtain the corresponding hydrogel, denoted as AM2.
[0036] Example 3
[0037] Add 3g of sodium alginate to 50mL of deionized water and stir for 4 hours to obtain the SA solution. Then add 40g of acrylamide to 100mL of deionized water and stir for 3 hours to obtain the AM solution. Stir the SA solution, AM solution, and 0.5g of ZIF8 for 1 hour, add 0.75g of potassium persulfate (APS) and 0.04g of MBA, and stir for another 30 minutes. Pour the resulting solution into a 1mm thick mold and place it in a 50℃ oven for 20 minutes to obtain the corresponding hydrogel, denoted as AM3.
[0038] Example 4
[0039] Add 2g of sodium alginate to 50mL of deionized water and stir for 4h to obtain SA solution; then add 30g of acrylamide to 100mL of deionized water and stir for 3h to obtain AM solution. Stir SA solution, AM solution and 0.5g of ZIF8 for 1h, add 0.75g of potassium persulfate (APS) and 0.04g of MBA and stir for another 30min. Pour the resulting solution into a 1mm thick mold and place it in a 50℃ oven for 20min to obtain the corresponding hydrogel, denoted as AM4.
[0040] Example 5
[0041] Add 2g of sodium alginate to 50mL of deionized water and stir for 4 hours to obtain the SA solution; then add 20g of acrylamide to 100mL of deionized water and stir for 3 hours to obtain the AM solution. Stir the SA solution, AM solution, and 0.5g of ZIF8 for 1 hour, then add 0.75g of potassium persulfate (APS) and 0.04g of MBA and stir for another 30 minutes. Pour the resulting solution into a 1mm thick mold and place it in a 50℃ oven for 20 minutes to obtain the corresponding hydrogel, denoted as AM5 (see [link to product description]). Figure 1 (Provides a side view of AM5).
[0042] Comparative Example 1
[0043] Compared to Example 2, no ZIF8 nanoparticles were added, and all other conditions were the same.
[0044] Comparative Example 2
[0045] Compared to Example 2, sodium alginate was not added; only acrylamide and ZIF8 were used, and all other conditions were the same.
[0046] Comparative Example 3
[0047] Compared to Example 2, no acrylamide was added; only sodium alginate and ZIF8 were used, and all other conditions were the same.
[0048] To verify the zinc-ion battery gel of the present invention, the battery gels of the above embodiments and comparative examples were subjected to the following tests: A. Mechanical property testing: The tensile strength and elongation at break of the gel film were tested using a universal testing machine. The results are shown in Table 1.
[0049] sample Tensile strength (MPa) Elongation at break (%) Elastic modulus (MPa) AM1 0.85 320 0.45 AM2 1.23 380 0.62 AM3 1.45 350 0.78 AM4 1.05 410 0.51 AM5 0.92 450 0.42 Comparative Example 1 0.68 280 0.38 Comparative Example 2 0.52 520 0.21 Comparative Example 3 0.95 120 1.12
[0050] As shown in the table above, the battery gel electrolyte prepared by this invention has excellent mechanical properties, which is mainly attributed to the interpenetrating double network structure formed by sodium alginate and polyacrylamide, as well as the reinforcing effect of ZIF8 nanoparticles.
[0051] B. Ionic conductivity test: The ionic conductivity of the gel electrolyte in 2M ZnSO4 (zinc sulfate aqueous solution with a concentration of 2 mol / L) electrolyte was tested by electrochemical impedance spectroscopy. The results are shown in Table 2.
[0052] sample Ionic conductivity (mS / cm) Activation energy (eV) AM1 18.5 0.21 AM2 22.3 0.18 AM3 20.8 0.19 AM4 19.2 0.20 AM5 16.7 0.23 Comparative Example 1 12.4 0.28 Comparative Example 2 15.8 0.25 Comparative Example 3 8.6 0.32
[0053] As shown in the table above, the introduction of ZIF8 significantly improves the ionic conductivity of the gel, thanks to the regular pore structure of ZIF8 providing a fast channel for zinc ion transport.
[0054] C. Electrochemical performance testing: Zn / / Zn symmetric cells and Zn / / MnO2 full cells were assembled using gel membranes as electrolytes, and their cycle performance was tested. Zn / / Zn symmetric cells at 1mA / cm 2 At the current density, the battery assembled in Example 2 can cycle stably for more than 800 hours without short circuit, while the battery in Comparative Example 1 only cycles for 350 hours before short circuit occurs.
[0055] The Zn / / MnO2 full cell assembled in Example 2 at a 0.5C rate had an initial discharge specific capacity of 285 mAh / g and a capacity retention of 82.3% after 500 cycles.
[0056] The battery assembled in Comparative Example 1 had an initial discharge specific capacity of 265 mAh / g, and its capacity retention rate was only 68.5% after 500 cycles.
[0057] Clearly, the zinc-ion battery using the gel electrolyte of this invention exhibits good cycle stability, indicating that the gel can effectively inhibit zinc dendrite growth.
[0058] D. Morphological characterization: Scanning electron microscopy showed that the gel membrane prepared in Example 2 had a uniform porous structure, with ZIF8 nanoparticles uniformly dispersed in the polymer network, while the gel membrane of Comparative Example 1 had uneven pore distribution and large pores.
[0059] The test results above show that the ratio of sodium alginate to acrylamide has a significant impact on gel performance, and the AM2 gel in Example 2 has the best overall performance.
[0060] This invention provides a method for preparing a zinc-ion battery gel. An interpenetrating double network structure is formed by sodium alginate and polyacrylamide, combining the excellent film-forming properties of sodium alginate with the high water absorption of polyacrylamide, thus improving the gel's mechanical strength and liquid retention capacity. The introduction of ZIF8 nanoparticles not only enhances the gel's mechanical properties, but their regular pore structure also provides a rapid channel for zinc ion transport, improving ionic conductivity. The zinc metal centers in ZIF8 exhibit a common ion effect with zinc ions in the electrolyte, which can homogenize the zinc ion flow, inhibit dendrite growth, and extend battery cycle life. In summary, the beneficial effects of this invention are: it can effectively improve the mechanical strength and liquid retention capacity of the gel, and can extend battery cycle life while improving ionic conductivity.
[0061] Of course, the present invention may have other various embodiments. Without departing from the spirit and essence of the present invention, those skilled in the art can make various corresponding changes and modifications according to the present invention, but these corresponding changes and modifications should all fall within the protection scope of the appended claims.
Claims
1. A method for preparing a zinc-ion battery gel, characterized in that, Includes the following steps: S1. Add sodium alginate to deionized water and stir to obtain SA solution; S2. Add acrylamide to deionized water and stir to obtain AM solution; S3. Mix SA solution, AM solution and ZIF8, add initiator and crosslinking agent, stir and pour into mold and dry to obtain zinc ion battery gel.
2. The method for preparing zinc-ion battery gel according to claim 1, characterized in that, The sodium alginate has a mass concentration of 1-6 wt% and a stirring time of 2-6 hours, while the acrylamide has a mass concentration of 10-40 wt% and a stirring time of 2-5 hours.
3. The method for preparing zinc-ion battery gel according to claim 1, characterized in that, The mold in S3 is 0.5~2mm thick.
4. The method for preparing zinc-ion battery gel according to claim 1, characterized in that, The initiator is potassium persulfate, and the crosslinking agent is N,N'-methylenebisacrylamide.
5. The method for preparing zinc-ion battery gel according to claim 1, characterized in that, The initiator is at least one of potassium persulfate, ammonium persulfate, or azobisisobutyronitrile, and the amount added is 1% to 3% of the mass of acrylamide.
6. The method for preparing zinc-ion battery gel according to claim 1, characterized in that, The crosslinking agent is at least one of N,N'-methylenebisacrylamide, ethylene glycol dimethacrylate, or polyethylene glycol diacrylate, and the amount added is 0.05% to 0.2% of the mass of acrylamide.
7. The method for preparing zinc-ion battery gel according to claim 1, characterized in that, The stirring time in S1 is 4 hours, the stirring time in S2 is 3 hours, the mixing time in S3 is 1 hour, and the stirring time is 30 minutes.
8. The method for preparing zinc-ion battery gel according to claim 4, characterized in that, In step S3, the temperature of the drying oven is 50°C and the drying time is 20 minutes.
9. A composite gel electrolyte prepared according to any one of claims 1 to 8, characterized in that, It includes a sodium alginate network, a polyacrylamide network, and ZIF8 nanoparticles dispersed in the dual network.
10. A zinc-ion battery, based on the composite gel electrolyte of claim 9, characterized in that, The composite gel electrolyte is included as an electrolyte or a membrane.