Zinc metal battery stable at low temperature by constructing protonated amino hydrophobic interface layer

Abstract

The invention discloses an application of a zinc metal battery stable at a low temperature by constructing a protonated amino hydrophobic interface layer, an electrolyte comprises a zinc salt and a solvent, the solvent comprises water and L-arginine (L-A), and the molar concentration is 0-0.05 mol / L. The protonated amino hydrophobic interface layer is constructed by adding a proper amount of L-A into the zinc salt solution, so that the cycling stability of the zinc anode interface is effectively protected. And parasitic reactions such as hydrogen evolution and corrosion are effectively inhibited. The zinc symmetric battery assembled by the invention can stably operate for more than 4500 hours under the condition of-20 DEG C.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of electrochemical energy storage, in particular to the preparation of aqueous zinc-ion battery electrolyte and the application of the battery. BACKGROUND

[0002] With the surge in global energy demand, it is urgent to find sustainable and clean energy storage systems. Secondary batteries, as a key energy storage technology, play a core role in the field of renewable energy utilization and electric vehicles, but mainstream lithium-ion batteries face the bottleneck of limited resources, high cost and poor safety. Aqueous zinc-ion batteries have attracted widespread attention due to their abundant zinc resources, low cost, excellent safety and environmental friendly characteristics. However, its commercialization process is still subject to multiple challenges: dendrites formed during the charging process of zinc anode deposition may cause internal short circuit, significantly reducing the cycle life; corrosion and passivation in aqueous environment further exacerbate performance decline; hydrogen evolution reaction and byproduct generation are also major obstacles. In response to these problems, researchers have explored strategies such as zinc anode soaking, artificial coating and electrolyte modification. The present application proposes an innovative technical solution: a protonated amino hydrophobic interface layer is constructed by adding electrolyte additives, effectively inhibiting side reactions such as hydrogen evolution and promoting uniform zinc deposition. This solution exhibits excellent stability at low temperatures of -20°C, enabling stable cycling for over 4500 hours. SUMMARY

[0003] The present application aims to provide a general aqueous zinc-ion battery (AZIBs) electrolyte and its application, solving the problem of the growth of dendrites and the generation of side reactions such as hydrogen evolution in conventional AZIBs, leading to the deterioration of the electrochemical performance of AZIBs at room temperature. By adding an appropriate amount of L-arginine (L-A) to the zinc salt solution, stable zinc cycling performance is achieved under low temperature conditions, thereby improving the service life of zinc metal batteries. To achieve the above purpose, the present application adopts the following technical solutions: The aqueous zinc-ion battery electrolyte is mainly composed of zinc salt, organic solvent additive and water.

[0004] Based on the above scheme, the zinc salt is any one or a combination of at least two of zinc sulfate, zinc chloride, zinc nitrate, zinc acetate, zinc phosphate, zinc trifluoromethylsulfonate, zinc bis-trifluoromethylsulfonimide, zinc tetrafluoroborate, zinc hexafluorophosphate, and zinc perchlorate, further preferably zinc perchlorate.

[0005] Based on the above scheme, the organic solvent additive is an amino acid.

[0006] Based on the above scheme, the amino acid derivative is one or a combination of at least two of glutamic acid, glycine, L-aspartic acid, and L-arginine, further preferably L-arginine.

[0007] The concentration of the electrolyte salt is 0 M-0.05 M, wherein M is the mass concentration, that is, the ratio of the number of moles of the electrolyte salt to the mass of the solvent M: mol kg -1 .

[0008] Based on the above scheme, preferably, the zinc salt concentration is 0.1-3 mol kg -1 (M), and further preferably 3 M.

[0009] Based on the above scheme, preferably, the content in the electrolyte is 0-8.7 g L -1 , The aqueous ion battery electrolyte is specifically 0 L-A, 0.01 L-A, 0.03 L-A, 0.05 L-A.

[0010] Based on the above scheme, preferably, the zinc ion battery is composed of a positive electrode, a film and a zinc negative electrode material. The positive electrode is selected from zinc ion intercalation and deintercalation type materials, and the manganese-based material is one or both of MnO2, Ca 0.28 MnO2; the vanadium-based material is one or more than one of V2O5, V2O3, Zn2V2O7, KV3O8 and NH4V4O 10 ; the film is a glass fiber membrane or a Celgard membrane; and the zinc negative electrode is a zinc foil or a zinc powder.

[0011] The application also provides the application of the aqueous ion battery electrolyte in improving the cycle life of the zinc metal battery under low temperature conditions.

[0012] Innovation The L-arginine (L-A) additive is introduced into the electrolyte, and the generation of side reactions at the zinc anode interface is further inhibited by constructing a protonated amino hydrophobic interface layer. The amino group (-NH2) of L-A is preferentially adsorbed on the surface of the zinc anode, and is protonated at the zinc interface to form a positively charged -NH3 + group. The group is combined with the zinc surface through electrostatic interaction to form a hydrophobic interface layer, effectively inhibiting the corrosion of water molecules and realizing the stable cycle of the zinc metal battery under low temperature conditions. Advantages of the application: A new type of electrolyte additive is used, a protonated amino hydrophobic interface layer is constructed at the zinc anode interface, the corrosion of water molecules is effectively inhibited, and the cycle performance of the zinc metal battery under low temperature is greatly improved. The assembled Zn || Zn symmetric battery can achieve more than 4500 hours of normal temperature cycle at-20℃ and at 1 mA cm −2 and 1 mA h cm −2 . Even at-20℃ and at 1 mA cm−2 and 1 mA h cm −2 Below, still can stable cycle 3200 hours, show excellent cycle performance. In particular, using 0.03 L-A electrolyte battery at -40℃ and 0.5 mA cm −2 and 0.5 mA h cm −2 Below, with more than 2000 hours of stable cycle life, indicating that zinc battery has good cycle stability. Zn || NH4V4O 10 Full cell, even after 150 cycles, the capacity almost no significant attenuation. BRIEF DESCRIPTION OF DRAWINGS

[0013] Figure 1 is a CA curve comparison of 0 L-A and 0.03 L-A electrolyte in Example 1.

[0014] Figure 2 is a CV curve comparison of 0 L-A and 0.03 L-A electrolyte assembled Zn || Cu asymmetric battery in Example 2.

[0015] Figure 3 is a Lsv curve comparison of 0 L-A and 0.03 L-A electrolyte assembled Zn || Ti asymmetric battery in Example 3.

[0016] Figure 4 is an XRD diagram of zinc foil after cycling in 0 L-A and 0.03 L-A electrolyte in Example 4.

[0017] Figure 5 is a Tafel curve comparison of 0 L-A and 0.03 L-A electrolyte assembled Zn || Zn symmetric battery in Example 5.

[0018] Figure 6 is a cycle diagram of Zn || Zn symmetric battery in various electrolytes at -20℃ low temperature at 1 mA cm −2 and 1 mA h cm −2 in Example 6.

[0019] Figure 7 is a cycle diagram of Zn || Zn symmetric battery in various electrolytes at -20℃ low temperature at 5 mA cm −2 and 1 mA h cm −2 in Example 7.

[0020] Figure 8 is a cycle diagram of Zn || Zn symmetric battery in various electrolytes at -40℃ low temperature at 0.5 mA cm −2 and 0.5 mA h cm −2cycling stability.

[0021] Figure 9 is a cyclic voltammogram of Zn || NH4V4O 10 Cycling diagram of button cell at -20℃ low temperature.

[0022] Figure 10 is a comparison chart of in-situ optical microscopy testing of 0 L-A and 0.03 L-A electrolyte in Example 10.

[0023] Figure 11 is a cyclic voltammogram of Zn || NH4V4O 10 Application diagram of soft package battery. DETAILED DESCRIPTION

[0024] The following examples are further illustrations of the application and are not intended to limit the scope of the application.

[0025] Example 1: Prepare 3 M zinc perchlorate mixed electrolyte with water as solvent, and the added amount of L-A is 0.00 M (0 L-A).

[0026] Prepare 3 M zinc perchlorate mixed electrolyte with water as solvent, and the added amount of L-A is 0.01 M (0.01 L-A).

[0027] Prepare 3 M zinc perchlorate mixed electrolyte with water as solvent, and the added amount of L-A is 0.03 M (0.03 L-A).

[0028] Prepare 3 M zinc perchlorate mixed electrolyte with water as solvent, and the added amount of L-A is 0.05 M (0.5 L-A).

[0029] Example 1: 0 L-A, 0.03 L-A electrolyte in Example 1.

[0030] Button cell test was used, and Zn || Zn symmetric battery was assembled with 0 L-A and 0.03 L-A electrolyte respectively and CA test was carried out respectively. The results are shown in Figure 1 Zinc battery in 0.03 L-A electrolyte showed obvious 3D diffusion trend, while in 0 L-A electrolyte, it was obvious 2D diffusion process, which indicated that 0.03 L-A promoted uniform zinc deposition.

[0031] Example 2: 0 L-A, 0.03 L-A electrolyte in Example 1.

[0032] Zn || Cu asymmetric cells were assembled using 0 L-A and 0.03 L-A electrolytes respectively and were subjected to Zn-Cu CV tests. The results are shown in Figure 2. In comparison with 0 L-A, the Zn battery in 0.03 L-A electrolyte showed a higher nucleation overpotential, indicating that L-A electrolyte promotes the nucleation process and enhances the driving force for compact zinc deposition nucleation. Figure 2 In comparison with 0 L-A, the Zn battery in 0.03 L-A electrolyte showed a higher nucleation overpotential, indicating that L-A electrolyte promotes the nucleation process and enhances the driving force for compact zinc deposition nucleation.

[0033] Example 3: 0 L-A and 0.03 L-A electrolytes in Example 1.

[0034] Zn || Ti asymmetric cells were assembled using 0 L-A and 0.03 L-A electrolytes respectively and were subjected to Lsv tests. The results are shown in Figure 3. In comparison with 0 L-A, the hydrogen evolution potential of the Zn battery in 0.03 L-A electrolyte was significantly shifted negatively, indicating that L-A electrolyte can effectively inhibit the hydrogen evolution reaction. Figure 3 In comparison with 0 L-A, the hydrogen evolution potential of the Zn battery in 0.03 L-A electrolyte was significantly shifted negatively, indicating that L-A electrolyte can effectively inhibit the hydrogen evolution reaction.

[0035] Example 4: 0 L-A and 0.03 L-A electrolytes in Example 1.

[0036] Zn || Zn symmetric cells were assembled using 0 L-A and 0.03 L-A electrolytes respectively and were subjected to constant current charge-discharge tests at 2 mA cm -2 , 2 mAh cm -2 . The zinc foils after 30 cycles of deposition were cleaned with deionized water and dried, and the surface of the zinc foils was analyzed by XRD. The test results are shown in Figure 4. After cycling in 0 L-A electrolyte, obvious byproduct peaks appeared on the surface of the zinc foils. However, no obvious byproduct peaks appeared on the surface of the zinc foils after cycling in 0.03 L-A electrolyte. The above results indicate that the hydrogen evolution corrosion reaction of zinc is effectively inhibited in 0.03 L-A electrolyte.

[0037] Example 5: 0 L-A and 0.03 L-A electrolytes in Example 1.

[0038] Zn || Zn symmetric cells were assembled using 0 L-A and 0.03 L-A electrolytes respectively and were subjected to Tafel tests. The results are shown in Figure 5. In comparison with 0 L-A, the Zn battery in 0.03 L-A electrolyte showed a lower corrosion current and a more positive corrosion potential, indicating that L-A electrolyte can significantly improve the corrosion phenomenon of the zinc anode interface.

[0039] Example 6: Example 1 0 L-A, 0.01 L-A, 0.03 L-A, 0.05 L-A electrolyte.

[0040] Zn || Zn symmetric cells were assembled using four electrolytes at 1 mA cm -2 , 1 mAh cm -2 Charging and discharging tests were carried out at -20℃.

[0041] The test results are shown in Figure 6. At -20℃, the Zn || Zn symmetric cell using 0.03 L-A mixed electrolyte can be stably cycled for more than 4500 h compared with 0 L-A electrolyte. It shows that 0.03 L-A electrolyte can inhibit the growth of zinc dendrites and hydrogen evolution reaction, and significantly improve the cycle stability of the battery.

[0042] Example 7: Example 1 0 L-A, 0.01 L-A, 0.03 L-A, 0.05 L-A electrolyte.

[0043] Zn || Zn symmetric cells were assembled using four electrolytes at 5 mA cm -2 , 1 mAh cm -2 Charging and discharging tests were carried out at -20℃.

[0044] The test results are shown in Figure 7. At -20℃, the Zn || Zn symmetric cell using 0.03 L-A electrolyte has a longer stable cycle time compared with 0 S-Gly electrolyte. It shows that the introduction of L-A additive effectively inhibits the occurrence of zinc anode interface side reaction, and greatly improves the stability of zinc anode.

[0045] Example 8: Zn || Zn symmetric cells were assembled using 0 L-A, 0.01 L-A, 0.03 L-A, 0.05 L-A electrolyte in Example 1 at 0.5 mA cm -2 , 0.5 mAh cm -2 Charging and discharging tests were carried out at -40℃.

[0046] The test results are shown in Figure 8. The zinc symmetric cell using 0 L-A electrolyte can only be stably cycled for 150 h, while the zinc symmetric cell using 0.03 L-A electrolyte can be stably cycled for 2000 h. It shows that 0.03 L-A electrolyte can realize reversible deposition and dissolution of zinc at low temperature.

[0047] Example 9: 0 S-Gly and 0.5 S-Gly electrolyte in Example 1 were used.

[0048] NH4V4O 10 Positive material: In the first step, 1.17 grams of ammonium metavanadate was weighed and dissolved in 70 milliliters of deionized water. In the second step, 1.891 g of oxalic acid powder was weighed and dissolved in the above solution, and stirred uniformly. The stirring was continued for 20 minutes. In the third step, the obtained mixture was transferred to a 100 mL polytetrafluoroethylene autoclave, the temperature was adjusted to 140°C for 12 hours, and a high-temperature water bath was performed. In the fourth step, after cooling, the obtained solid precipitate was centrifuged several times with ethanol and deionized water, and dried at 70°C overnight. In the fifth step, during the electrode preparation process, the synthesized NH4V4O 10 The solid precipitate was ground, and the obtained NH4V4O 10 The powder was uniformly mixed with the conductive additive Super P carbon black and the PVDF binder in a mass ratio of 7:2:1 to finally prepare the electrode. The mixing process needs to ensure that each component is fully dispersed to obtain a uniform electrode slurry. In the sixth step, the prepared electrode was dried in a vacuum oven at 70°C for 8 hours.

[0049] Battery assembly: Zn || NH4V4O 10 The full cell was charged and discharged at 5A g -1 The test conditions were carried out at room temperature.

[0050] The test results are shown in Figure 9. The Zn || NH4V4O 10 full cell using 0 L-A electrolyte has a significant capacity decay. The Zn || NH4V4O 10 full cell using 0.03 L-A electrolyte has no obvious capacity decay after 150 cycles. It shows that 0.03 L-A electrolyte can realize the stable operation of the full cell.

[0051] Example 10: In-situ optical microscopic test was carried out using 0 L-A, 0.03 L-A electrolyte in Example 1. The test results are shown in Figure 10 The zinc foil using 0 L-A electrolyte observed obvious zinc dendrite growth phenomenon with the extension of observation time, while the zinc anode in 0.03 L-A electrolyte formed a uniform and dense zinc deposition layer without obvious zinc dendrite growth phenomenon, which shows that 0.03 L-A can effectively inhibit the growth of zinc dendrites.

[0052] Example 11: 0.03 L-A electrolyte in Example 1 was used.

[0053] Assembled Zn || NH4V4O 10 The soft package full battery was assembled and application test was carried out. The test results are shown in Figure 11. The soft package battery using 0.03L-A electrolyte can light the lamp at room temperature, which shows that the L-A electrolyte additive has practical application value.

Claims

1. An aqueous zinc-ion battery electrolyte, characterized in that, The electrolyte comprises a zinc salt and a solvent, and the solvent comprises water and an L-A (L-arginine) additive.

2. The electrolyte according to claim 1, characterized in that, The molar concentration of the L-A is 0-0.05 mol / L.

3. The electrolyte according to claim 2, characterized in that, The content of the L-A in the solvent is 0-8.7 g / L.

4. The electrolyte of claim 1, wherein, The zinc salt is any one or a combination of at least two of zinc sulfate, zinc chloride, zinc nitrate, zinc acetate, zinc phosphate, zinc trifluoromethylsulfonate, zinc bistrifluoromethylsulfonimide, zinc tetrafluoroborate, zinc hexafluorophosphate, and zinc perchlorate.

5. The electrolyte according to claim 4, characterized in that, The zinc salt is zinc perchlorate.

6. The electrolyte of claim 1, wherein, The concentration of the zinc salt in the electrolyte is 3 mol / L.

7. An aqueous zinc-ion battery, characterized in that, The aqueous zinc ion battery comprises the electrolyte according to any one of claims 1-6.

8. The zinc-ion battery of claim 7, wherein, The zinc ion battery comprises a positive electrode, a film and a zinc negative electrode; the positive electrode is selected from zinc ion intercalation / deintercalation materials, the zinc ion intercalation / deintercalation materials are one or a combination of manganese-based materials and vanadium-based materials; the manganese-based materials are one or two of MnO2, Ca 0.28 MnO2; the vanadium-based materials are one or more than one of V2O5, V2O3, Zn2V2O7 and NH4V4O 10 7; the film is a glass fiber film or a Celgard film; and the zinc negative electrode is a zinc foil or a zinc powder.

9. The zinc-ion battery of claim 8, wherein, The positive electrode is NH4V4O 10 ; the membrane is a glass fiber membrane; and the zinc negative electrode is a zinc foil.

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