L-cysteine doped ammonium vanadate positive electrode material and preparation method and application thereof in aqueous zinc ion battery
By using a method for preparing L-cysteine-doped ammonium vanadate cathode material, the problems of conductivity and cycle stability of aqueous zinc-ion battery cathode materials have been solved, achieving high-capacity and high-power-density battery performance, suitable for large-scale energy storage systems.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-26
- Publication Date
- 2026-03-31
AI Technical Summary
Existing aqueous zinc-ion battery cathode materials suffer from poor conductivity, structural instability, unavoidable dissolution, and unsatisfactory reversibility, resulting in poor conductivity, limited rate performance, and limited cycle performance, making it difficult to meet the needs of large-scale energy storage systems.
The preparation method of L-cysteine-doped ammonium vanadate cathode material involves adding L-cysteine to ammonium metavanadate solution and carrying out a hydrothermal reaction to form L-cysteine-doped ammonium vanadate (L-NVO). The cathode material is then mixed with conductive materials and binders to prepare a cathode sheet, which is then assembled into an aqueous zinc-ion battery.
It significantly improves the conductivity and ion diffusion rate of the material, expands the interlayer spacing, improves cycle stability, and increases the capacity to 350 mAh/g. It features low cost, environmental friendliness, and high safety, making it suitable for large-scale production.
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Figure CN121769074A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of materials technology, specifically relating to an L-cysteine-doped ammonium vanadate cathode material, its preparation method, and its application in aqueous zinc-ion batteries. Background Technology
[0002] Given the continued depletion of global resources and the urgent need for natural resource and environmental protection, the sustainability of energy systems heavily reliant on non-renewable fossil fuels is increasingly untenable. Therefore, the trajectory of global energy development has shifted towards the development and utilization of alternative clean energy sources, including but not limited to wind, tidal, and biomass energy. However, their availability is intermittent due to inherent volatility. To overcome this challenge and maximize the benefits of these renewable energy sources, innovation and enhancement of specialized energy storage technologies are crucial. Energy storage devices that convert chemical energy into electrical energy are relatively mature, and effective methods for storing intermittent clean energy can enable large-scale energy transfer. Therefore, developing sustainable and renewable energy storage devices is an effective way to address issues such as the energy crisis and climate change. In recent years, while lithium-ion batteries have dominated electrochemical energy storage, they still face many challenges in large-scale stationary energy storage systems, such as safety issues, cost-effectiveness, and the sustainability of lithium metal. As one of the emerging candidate materials, aqueous zinc-ion batteries (AZIBs) stand out due to their abundant resources, low cost, ideal theoretical capacity, low zinc anodic redox potential (-0.76 V compared to standard hydrogen electrodes), and environmental friendliness. Currently, many cathode materials have been applied to AZIBs, such as manganese-based compounds, vanadium-based compounds, transition metal dihalides (TMDs), Prussian blue and its analogues, and organic compounds. However, these materials suffer from low intrinsic electronic conductivity, structural instability, unavoidable dissolution, and unsatisfactory reversibility, resulting in poor conductivity, limited rate performance, specific capacity, and cycle performance, making it difficult to meet the growing demand. Summary of the Invention
[0003] To address the aforementioned technical problems, this invention provides an L-cysteine-doped ammonium vanadate cathode material, its preparation method, and its application in aqueous zinc-ion batteries.
[0004] The technical solution adopted in this invention is: an L-cysteine-doped ammonium vanadate cathode material, the preparation method of which includes the following steps: adding ammonium metavanadate and oxalic acid to deionized water, stirring at room temperature, adding L-cysteine to the resulting mixed solution, and continuing to stir to mix thoroughly; transferring the resulting mixed solution to a stainless steel hydrothermal reactor lined with polytetrafluoroethylene, carrying out a hydrothermal reaction, cooling to room temperature, centrifuging and washing, and vacuum drying to obtain the L-cysteine-doped ammonium vanadate cathode material (L-NVO).
[0005] Furthermore, in the above-mentioned L-cysteine-doped ammonium vanadate cathode material, the molar ratio of ammonium metavanadate to oxalic acid is 1:1.
[0006] Furthermore, in the aforementioned L-cysteine-doped ammonium vanadate cathode material, the mass of added L-cysteine is 5~25 mg.
[0007] Furthermore, in the above-mentioned L-cysteine-doped ammonium vanadate cathode material, the hydrothermal reaction conditions are: reaction at 180 °C for 30 min.
[0008] The application of any of the above-mentioned L-cysteine-doped ammonium vanadate cathode materials in aqueous zinc-ion batteries.
[0009] Furthermore, the application method includes the following steps:
[0010] 1) Preparation of positive electrode sheet: After L-cysteine-doped ammonium vanadate positive electrode material L-NVO is mixed evenly with binder and conductive material, a small amount of NMP is added as solvent. After mixing evenly, it is directly coated on the substrate carbon paper, vacuum dried, and taken out to obtain positive electrode sheet coated with L-NVO.
[0011] 2) Preparation of negative electrode sheet: The zinc sheet is sanded with sandpaper to remove the oxide layer on the surface, and the sanded zinc sheet is cut into a circular negative electrode sheet with a diameter of 12 mm.
[0012] 3) Using the positive electrode sheet prepared in step 1) as the positive electrode and the negative electrode sheet prepared in step 2) as the negative electrode, and the electrolyte as 2M zinc trifluoromethanesulfonate, an aqueous zinc-ion battery is obtained.
[0013] Furthermore, in the above application method, step 1), the adhesive is PVDF.
[0014] Furthermore, in the above application method, step 1), the conductive material is Super-p.
[0015] Furthermore, in the above application method, in step 1), the mass ratio of L-NVO to PVDF and Super-p is 8:1:1.
[0016] Furthermore, in the above application method, step 2), the zinc sheet has a thickness of 0.1mm-0.2mm and a purity of 99.99%.
[0017] The beneficial effects of this invention are:
[0018] 1. This invention significantly improves the conductivity and ion diffusion rate of L-cysteine-doped ammonium vanadate cathode material through one-step synthesis, and also reduces the internal resistance.
[0019] 2. In this invention, the introduction of L-cysteine expands the interlayer spacing of ammonium vanadate (NVO), alters the charge distribution, and increases the Zn content. 2+ The migration rate in hybrid materials improves the cycling stability of the material.
[0020] 3. This invention has the characteristics of low cost, environmental friendliness, and high safety.
[0021] 4. This invention has advantages such as high energy density and power density.
[0022] 5. The present invention has a simple synthesis and assembly process, is easy to operate and control, and is suitable for continuous large-scale production.
[0023] 6. In this invention, after modification, the capacity of the electrode material is increased from 162 mAh / g to 350 mAh / g.
[0024] 7. The method of the present invention is applicable to other metal oxide cathode materials. Attached Figure Description
[0025] Figure 1 These are the XRD spectra of NVO and L-NVO prepared in Example 1.
[0026] Figure 2 This is a cyclic voltammetry curve of NVO and L-NVO prepared in Example 1.
[0027] Figure 3 This is the TEM spectrum of L-NVO prepared in Example 1.
[0028] Figure 4 This is a specific capacity diagram of NVO and L-NVO prepared in Example 1. Detailed Implementation
[0029] The technical solution of the present invention will be further described below, but it is not limited thereto. Any modifications or equivalent substitutions to the technical solution of the present invention that do not depart from the spirit and scope of the technical solution of the present invention should be covered within the protection scope of the present invention.
[0030] Example 1: L-cysteine-doped ammonium vanadate cathode material (L-NVO)
[0031] (a) The preparation method of L-NVO is as follows:
[0032] Ammonium metavanadate (234 mg, 2 mmol) and oxalic acid (252 mg, 2 mmol) were weighed and dissolved in 30 mL of deionized water. The mixture was stirred at room temperature. 5 mg of L-cysteine was added to the resulting mixture, and stirring was continued to ensure thorough mixing. The resulting mixture was then transferred to a polytetrafluoroethylene-lined stainless steel hydrothermal reactor and reacted at 180 °C for 30 min. After cooling to room temperature, the residue was removed by centrifugation and the mixture was dried under vacuum to obtain the L-NVO electrode material.
[0033] (II) The preparation method of NVO is as follows:
[0034] Ammonium metavanadate (234 mg, 2 mmol) and oxalic acid (252 mg, 2 mmol) were weighed and dissolved in 30 mL of deionized water. The mixture was stirred at room temperature to ensure thorough mixing. The resulting solution was then transferred to a polytetrafluoroethylene-lined stainless steel hydrothermal reactor and reacted at 180 °C for 30 min. After cooling to room temperature, the reactor was centrifuged to remove residual reactants and then vacuum dried to obtain the NVO electrode material.
[0035] (III) Testing
[0036] Figure 1 These are the XRD patterns of NVO and L-NVO prepared in this embodiment. Figure 1 As can be seen, the diffraction peaks of all samples matched well with NH4V3O8. After L-cysteine doping, the XRD patterns of the samples showed significant changes, with the intensity of most peaks weakening. This indicates that L-cysteine was successfully doped into ammonium vanadate.
[0037] Figure 2 This is a cyclic voltammetry graph of NVO and L-NVO. (From...) Figure 2 It is evident that the area enclosed by L-NVO is significantly larger than that of pure NVO, indicating that the capacity of L-NVO is greater than that of pure NVO.
[0038] Figure 3 This is the TEM image of L-NVO. (By...) Figure 3 It can be seen that the prepared L-NVO has a typical rod-like structure.
[0039] Figure 4 This is a specific capacity diagram of NVO and L-NVO. (From...) Figure 4 It is evident that the specific capacity of L-NVO is much higher than that of pure NVO.
[0040] Example 2: L-cysteine-doped ammonium vanadate cathode material (L-NVO)
[0041] The preparation method is as follows:
[0042] Ammonium metavanadate (234 mg, 2 mmol) and oxalic acid (252 mg, 2 mmol) were weighed and dissolved in 30 mL of deionized water. The mixture was stirred at room temperature. 10 mg of L-cysteine was added to the resulting mixture and stirred until fully mixed. The resulting mixture was then transferred to a polytetrafluoroethylene-lined stainless steel hydrothermal reactor and reacted at 180 °C for 30 min. After cooling to room temperature, the reactants were removed by centrifugation and vacuum drying to obtain the L-NVO electrode material.
[0043] Example 3: L-cysteine-doped ammonium vanadate cathode material (L-NVO)
[0044] The preparation method is as follows:
[0045] Ammonium metavanadate (234 mg, 2 mmol) and oxalic acid (252 mg, 2 mmol) were weighed and dissolved in 30 mL of deionized water. The mixture was stirred at room temperature. 25 mg of L-cysteine was added to the resulting mixture, and stirring was continued to ensure thorough mixing. The resulting mixture was then transferred to a polytetrafluoroethylene-lined stainless steel hydrothermal reactor and reacted at 180 °C for 30 min. After cooling to room temperature, the residues were removed by centrifugation and the mixture was dried under vacuum to obtain the L-NVO electrode material.
[0046] Example 4: Application of L-cysteine-doped ammonium vanadate cathode material in aqueous zinc-ion batteries
[0047] (I) Preparation of aqueous zinc-ion battery-1
[0048] 1) Preparation of the positive electrode:
[0049] The L-NVO electrode material prepared in Example 1 was mixed with PVDF and Super-p in a mass ratio of 8:1:1. A small amount of NMP was added as a solvent and mixed evenly. The mixture was then directly coated onto a carbon paper substrate, dried in a vacuum drying oven, and removed to obtain a positive electrode sheet coated with L-NVO material.
[0050] 2) Preparation of the negative electrode:
[0051] The zinc sheet with a thickness of 0.1 mm and a purity of 99.99% was repeatedly sanded with sandpaper to remove the oxide layer on the surface. The sanded zinc sheet was then cut into a circular negative electrode sheet with a diameter of 12 mm for later use.
[0052] 3) Using the positive electrode sheet prepared in step 1) as the positive electrode and the negative electrode sheet prepared in step 2) as the negative electrode, and the electrolyte as 2M zinc trifluoromethanesulfonate, an aqueous zinc-ion battery is obtained.
[0053] (II) Preparation of Aqueous Zinc-ion Battery-2
[0054] 1) Preparation of the positive electrode:
[0055] The L-NVO electrode material prepared in Example 2 was mixed with PVDF and Super-p in a mass ratio of 8:1:1. A small amount of NMP was added as a solvent and mixed evenly. The mixture was then directly coated onto a substrate carbon paper, dried in a vacuum drying oven, and removed to obtain a positive electrode sheet coated with L-NVO material.
[0056] 2) Preparation of the negative electrode:
[0057] Zinc sheets with a thickness of 0.1 mm and a purity of 99.99% are repeatedly sanded to remove the oxide layer on the surface. The sanded zinc sheets are then cut into circular negative electrode sheets with a diameter of 12 mm for later use.
[0058] 3) Using the positive electrode sheet prepared in step 1) as the positive electrode and the negative electrode sheet prepared in step 2) as the negative electrode, and the electrolyte as 2M zinc trifluoromethanesulfonate, an aqueous zinc-ion battery is obtained.
[0059] (III) Preparation of Aqueous Zinc-ion Battery-3
[0060] 1) Preparation of the positive electrode:
[0061] The L-NVO electrode material prepared in Example 3 was mixed with PVDF and Super-p in a mass ratio of 8:1:1. A small amount of NMP was added as a solvent and mixed evenly. The mixture was then directly coated onto a substrate carbon paper, dried in a vacuum drying oven, and removed to obtain a positive electrode sheet coated with L-NVO material.
[0062] 2) Preparation of the negative electrode:
[0063] Zinc sheets with a thickness of 0.1 mm and a purity of 99.99% are repeatedly sanded to remove the oxide layer on the surface. The sanded zinc sheets are then cut into circular negative electrode sheets with a diameter of 12 mm for later use.
[0064] 3) Using the positive electrode sheet prepared in step 1) as the positive electrode and the negative electrode sheet prepared in step 2) as the negative electrode, and the electrolyte as 2M zinc trifluoromethanesulfonate, an aqueous zinc-ion battery is obtained.
[0065] (iv) Preparation of aqueous zinc-ion battery-4
[0066] 1) Preparation of the positive electrode:
[0067] The L-NVO electrode material prepared in Example 1 was mixed with PVDF and Super-p in a mass ratio of 8:1:1. A small amount of NMP was added as a solvent and mixed evenly. The mixture was then directly coated onto a substrate carbon paper, dried in a vacuum drying oven, and removed to obtain a positive electrode sheet coated with L-NVO material.
[0068] 2) Preparation of the negative electrode:
[0069] The zinc sheet with a thickness of 0.2 mm and a purity of 99.99% was repeatedly sanded to remove the oxide layer on the surface. The sanded zinc sheet was then cut into a circular negative electrode sheet with a diameter of 12 mm for later use.
[0070] 3) Using the positive electrode sheet prepared in step 1) as the positive electrode and the negative electrode sheet prepared in step 2) as the negative electrode, and the electrolyte as 2M zinc trifluoromethanesulfonate, an aqueous zinc-ion battery is obtained.
[0071] (V) Preparation of Aqueous Zinc-ion Battery-5
[0072] 1) Preparation of the positive electrode:
[0073] The L-NVO electrode material prepared in Example 2 was mixed with PVDF and Super-p in a mass ratio of 8:1:1. A small amount of NMP was added as a solvent and mixed evenly. The mixture was then directly coated onto a substrate carbon paper, dried in a vacuum drying oven, and removed to obtain a positive electrode sheet coated with L-NVO material.
[0074] 2) Preparation of the negative electrode:
[0075] The zinc sheet with a thickness of 0.2 mm and a purity of 99.99% was repeatedly sanded to remove the oxide layer on the surface. The sanded zinc sheet was then cut into a circular negative electrode sheet with a diameter of 12 mm for later use.
[0076] 3) Using the positive electrode sheet prepared in step 1) as the positive electrode and the negative electrode sheet prepared in step 2) as the negative electrode, and the electrolyte as 2M zinc trifluoromethanesulfonate, an aqueous zinc-ion battery is obtained.
[0077] (vi) Preparation of aqueous zinc-ion battery-6
[0078] 1) Preparation of the positive electrode:
[0079] The L-NVO electrode material prepared in Example 3 was mixed with PVDF and Super-p in a mass ratio of 8:1:1. A small amount of NMP was added as a solvent and mixed evenly. The mixture was then directly coated onto a substrate carbon paper, dried in a vacuum drying oven, and removed to obtain a positive electrode sheet coated with L-NVO material.
[0080] 2) Preparation of the negative electrode:
[0081] The zinc sheet with a thickness of 0.2 mm and a purity of 99.99% was repeatedly sanded to remove the oxide layer on the surface. The sanded zinc sheet was then cut into a circular negative electrode sheet with a diameter of 12 mm for later use.
[0082] 3) Using the positive electrode sheet prepared in step 1) as the positive electrode and the negative electrode sheet prepared in step 2) as the negative electrode, and the electrolyte as 2M zinc trifluoromethanesulfonate, an aqueous zinc-ion battery is obtained.
[0083] (vii) Performance Testing
[0084] Electrochemical tests were conducted on the assembled aqueous zinc-ion batteries 1-6. We found that aqueous zinc-ion battery 1 exhibited the best electrochemical performance, showing improved specific capacity at all current densities (e.g., ...). Figure 4 As shown in the figure, since the mass ratio of ammonium metavanadate to L-cysteine in aqueous zinc-ion battery 1 is about 50:1, the L-NVO formed has a larger interlayer spacing and provides more active sites compared with pure NVO. Therefore, it is easier to store more zinc ions, and at the same time, it has a promoting effect on the insertion and extraction of zinc ions, thereby improving its electrochemical performance.
Claims
1. An L-cysteine-doped ammonium vanadate cathode material, characterized in that, The preparation method includes the following steps: adding ammonium metavanadate and oxalic acid to deionized water, stirring at room temperature, adding L-cysteine to the resulting mixed solution, and continuing to stir to mix thoroughly; The resulting mixed solution was transferred to a stainless steel hydrothermal reactor lined with polytetrafluoroethylene for hydrothermal reaction. After cooling to room temperature, the solution was centrifuged, washed, and vacuum dried to obtain L-cysteine-doped ammonium vanadate cathode material L-NVO.
2. The L-cysteine-doped ammonium vanadate cathode material according to claim 1, characterized in that, The molar ratio of ammonium metavanadate to oxalic acid is 1:
1.
3. The L-cysteine-doped ammonium vanadate cathode material according to claim 1, characterized in that, The mass of L-cysteine added is 5~25 mg.
4. The L-cysteine-doped ammonium vanadate cathode material according to claim 1, characterized in that, The hydrothermal reaction was carried out at 180 °C for 30 min.
5. The application of an L-cysteine-doped ammonium vanadate cathode material according to any one of claims 1-4 in an aqueous zinc-ion battery.
6. The application according to claim 5, characterized in that, The method includes the following steps: 1) Preparation of positive electrode: L-cysteine-doped ammonium vanadate positive electrode material L-NVO is mixed evenly with binder and conductive material, NMP is added dropwise as solvent, and after mixing evenly, it is directly coated on the substrate carbon paper, vacuum dried, and taken out to obtain positive electrode coated with L-NVO. 2) Preparation of negative electrode sheet: The zinc sheet is sanded with sandpaper to remove the oxide layer on the surface, and the sanded zinc sheet is cut into a circular negative electrode sheet with a diameter of 12 mm. 3) Using the positive electrode sheet prepared in step 1) as the positive electrode and the negative electrode sheet prepared in step 2) as the negative electrode, and the electrolyte as 2M zinc trifluoromethanesulfonate, an aqueous zinc-ion battery is obtained.
7. The application according to claim 6, characterized in that, In step 1), the adhesive is PVDF.
8. The application according to claim 7, characterized in that, In step 1), the conductive material is Super-p.
9. The application according to claim 8, characterized in that, In step 1), the mass ratio of L-NVO to PVDF and Super-p is 8:1:
1.
10. The application according to claim 6, characterized in that, In step 2), the zinc sheet has a thickness of 0.1 mm to 0.2 mm and a purity of 99.99%.