Preparation method and application of water-based tin battery electrolyte containing benzothiazole additive
By introducing benzothiazole additives into the electrolyte of aqueous tin batteries, the tin ion deposition behavior was regulated, solving the problems of interfacial stability and cycle performance of tin batteries, and achieving high-efficiency electrochemical performance and long lifespan.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- NANTONG UNIV
- Filing Date
- 2026-03-26
- Publication Date
- 2026-05-29
Smart Images
Figure CN122118128A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of electrochemical energy storage technology, and in particular to a method for preparing and applying an aqueous tin battery electrolyte containing benzothiazole additive. Background Technology
[0002] Tin metal, as a promising anode material for aqueous batteries, boasts advantages such as relatively abundant resources, low cost, and good environmental compatibility. Existing research indicates that tin metal exhibits a performance of approximately 452 mAh / g in aqueous battery systems. -1 With a theoretical specific capacity and a standard electrode potential of approximately -0.14 V (vs. SHE), it balances capacity and electrochemical activity while also exhibiting some hydrogen evolution tolerance, thus being considered a promising candidate material for aqueous metal anodes. However, existing aqueous tin metal batteries still suffer from significant interfacial stability issues during charge and discharge. On one hand, the deposition / stripping process of tin ions on the anode surface is prone to localized uneven reactions, leading to uneven particle size distribution, particle coarsening, particle agglomeration, and loose accumulation in the deposited products, which in turn causes increased polarization and decreased cycle performance. On the other hand, Sn... 2+ Hydrolysis and related side reactions are prone to occur in aqueous electrolytes, generating SnO, SnO2 or tin hydroxide interfacial byproducts, resulting in loss of active material and interfacial passivation, which further reduces coulombic efficiency and cycle stability.
[0003] Existing technologies typically improve the interfacial behavior of tin anodes by adjusting the type of tin salt, optimizing the acidic environment, or introducing functional organic additives. However, a method that is simple in composition, easy to prepare, and can simultaneously improve the performance of Sn is still lacking. 2+ A stable electrolyte system with uniform deposition and interfacial stability is needed. Therefore, developing a highly stable composite electrolyte suitable for aqueous tin metal batteries is of great significance. Summary of the Invention
[0004] The purpose of this invention is to overcome the shortcomings of existing technologies by proposing a method for preparing and applying an aqueous tin battery electrolyte containing benzothiazole additive, which utilizes an acidic environment to react Sn... 2+ The stability-maintaining effect and the adsorption regulation effect of benzothiazole molecules at the electrode interface improve Sn 2+ The interface transport and deposition behavior promotes the formation of a more uniform and denser deposition layer, reduces particle coarsening, agglomeration and loose accumulation, and inhibits the occurrence of side reactions, thereby improving the reversibility and structural stability of the tin anode, and thus improving the coulombic efficiency, capacity retention and cycle life of aqueous tin metal batteries.
[0005] To achieve the above objectives, the present invention adopts the following technical solution:
[0006] A method for preparing an aqueous tin battery electrolyte containing a benzothiazole additive, comprising the following steps:
[0007] Step 1: Prepare hydrochloric acid solution, tin salt solution and benzothiazole solution respectively. Before use, equilibrate the above raw materials at room temperature to reduce the impact of temperature difference on the uniformity of mixing.
[0008] Step 2: Measure 6-12 parts of hydrochloric acid solution and add it to a clean reaction vessel. Then measure 6-15 parts of tin salt solution and slowly add it to the hydrochloric acid solution. Stir the mixture at room temperature to allow the acidic medium to come into full contact with the tin salt and form a homogeneous and stable acidic tin salt precursor system.
[0009] Step 3: Under continuous stirring, slowly add 2-8 parts of benzothiazole solution to the acidic tin salt precursor system obtained in Step 2 to fully disperse the benzothiazole additive in the system and form a stable composite system with the tin salt.
[0010] Step 4: Continue stirring the mixture obtained in Step 3 at room temperature for 10-30 min, and then perform ultrasonic degassing treatment at an ultrasonic frequency of 12 kHz-36 kHz for 20-50 min to effectively remove dissolved gaseous impurities in the system, further improve the overall uniformity of the electrolyte, and promote the full mixing between the components, so as to finally obtain an aqueous tin battery electrolyte with uniform appearance and no obvious precipitation.
[0011] Step 5: Let the aqueous tin battery electrolyte obtained in Step 4 stand for 6–18 h to further stabilize the system.
[0012] Preferably, in step 1, the tin salt is one or more of tin methanesulfonate, stannous chloride, stannous sulfate, and stannous tetrachloride.
[0013] Preferably, in step 1, the concentration of the hydrochloric acid solution is 0.5–2.5 mol / L, the concentration of the tin salt solution is 0.5–3.5 mol / L, and the concentration of the benzothiazole solution is 5.0–10.0 mol / L.
[0014] Preferably, in step 1, the volume ratio of the hydrochloric acid solution, the tin salt solution, and the benzothiazole solution is 6-12:6-15:2-8.
[0015] The present invention also provides an application of the aqueous tin battery electrolyte containing benzothiazole additive obtained by the above preparation method in an aqueous tin metal battery, wherein the aqueous tin metal battery includes a positive electrode, a negative electrode, a separator and an aqueous tin battery electrolyte containing benzothiazole additive.
[0016] Preferably, the negative electrode is a Sn metal negative electrode, preferably tin foil or tin sheet, with a thickness of 50~300 μm.
[0017] Preferably, the diaphragm is one or more of glass fiber membrane, non-woven membrane, or porous polymer diaphragm.
[0018] Preferably, the positive electrode is an electrode sheet loaded on the current collector, and the electrode sheet is formed by pressing a mixture of positive electrode active material, conductive agent and binder into a film.
[0019] Preferably, the current collector is one or more of titanium mesh, stainless steel mesh, titanium foil, or stainless steel foil.
[0020] Preferably, the adhesive is one or more of polytetrafluoroethylene, polyvinylidene fluoride, sodium carboxymethyl cellulose, and styrene-butadiene rubber.
[0021] By adopting the above technical solution: the present invention lies in introducing benzothiazole additive into the acidic tin salt electrolyte system to synergistically regulate Sn. 2+ The solution chemical environment and the reaction process at the tin anode interface. Hydrochloric acid is used to maintain the acidic environment of the electrolyte and enhance the Sn... 2+ Its stability in aqueous systems mitigates hydrolysis and related side reactions; tin salts provide a source of soluble tin ions, offering stable active species for tin deposition / stripping; benzothiazoles can be adsorbed at the electrode / electrolyte interface through their aromatic heterocyclic structure and heteroatom sites, thereby affecting Sn. 2+ The interface transport, nucleation and growth behavior promotes the formation of a more uniform and denser deposition layer of tin on the negative electrode surface, reduces the coarsening, agglomeration and loose accumulation of deposition particles, and reduces the generation of interface by-products and the degree of electrode passivation.
[0022] Compared with the prior art, the present invention has the following beneficial effects:
[0023] 1. Multidimensional interface regulation: This invention utilizes the maintenance effect of hydrochloric acid on the acidic environment and the effect of tin methanesulfonate on the active Sn 2+ The stable supply function of benzothiazole and the adsorption regulation function of benzothiazole at the electrode / electrolyte interface have enabled the synergistic optimization of the reaction environment, ion deposition behavior and side reaction processes at the tin anode interface.
[0024] 2. Outstanding electrochemical performance: The Sn∥Sn symmetric cell using the aqueous tin battery electrolyte of this invention exhibits excellent electrochemical performance at 0.5 mA·cm⁻¹. -2 Current density, 0.5 mAh·cm -2Under the condition of areal capacity, the cycle life can reach 4000 hours, showing excellent long-term cycle stability; at the same time, the coulombic efficiency of Sn∥Cu coin half-cell can reach 99.81%, indicating that the electrolyte can effectively improve the reversibility of tin deposition / stripping process and significantly reduce irreversible losses.
[0025] 3. More stable deposition structure: The aqueous tin battery electrolyte of the present invention can regulate the nucleation and growth mode of tin on the negative electrode surface, so that the deposition layer is transformed from a coarse particle structure that is easy to accumulate in a disordered manner into a more uniform and dense deposition morphology, thereby improving the structural integrity and interfacial adhesion stability of the deposition layer.
[0026] 4. Simple and practical preparation process: The preparation process of the aqueous tin battery electrolyte of this invention does not require complex pretreatment. It only requires mixing the reagents in proportion, stirring, ultrasonic degassing, and allowing it to stand until stable to obtain the target electrolyte. The overall process is short, easy to operate, and has good repeatability. Moreover, the raw materials are widely available, which facilitates laboratory implementation and subsequent engineering scale-up.
[0027] 5. Strong application adaptability: The aqueous tin battery electrolyte of the present invention can not only be used in Sn metal anode systems, but also be further adapted to tin-based electrode systems, and can form a good compatibility with glass fiber separators and various aqueous battery cathode materials. Attached Figure Description
[0028] Figure 1 To achieve a Sn∥Sn symmetric cell using the electrolyte described in this invention at a current density of 0.5 mA·cm⁻¹ -2 The surface capacity is 0.5 mAh·cm³. -2 Figure showing the cyclic performance characterization results under the given conditions;
[0029] Figure 2 To construct a Sn∥Sn symmetric cell using the electrolyte described in this invention at 0.5 mA·cm⁻¹ -2 Current density and 0.5 mAh·cm -2 A magnified view of the time-voltage curve during the later stage of cycling under the areal capacity condition;
[0030] Figure 3 To test the Sn∥Cu coin cell using the aqueous tin battery electrolyte described in this invention at 1 mA·cm⁻¹ -2 Current density and 1 mAh·cm -2 Figure showing the Coulomb efficiency characterization results under the areal capacity condition. Detailed Implementation
[0031] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings, so that those skilled in the art can better understand the advantages and features of the present invention, thereby making a clearer definition of the scope of protection of the present invention. The embodiments described in this invention are only some embodiments of the present invention, not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.
[0032] Example 1
[0033] Step 1: Measure 6 portions of 1.0 mol / L hydrochloric acid solution and add them to a clean reaction vessel. Then, measure 6 portions of 3.0 mol / L tin methanesulfonate solution and slowly add them to the hydrochloric acid solution. Stir the mixture at room temperature to allow the acidic medium to come into full contact with the tin salt and form a homogeneous and stable acidic tin salt precursor system.
[0034] Step 2: Under continuous stirring, slowly add 3 parts of 7.5 mol / L benzothiazole solution to the acidic tin salt precursor system obtained in Step 1 to fully disperse the benzothiazole additive in the system and form a stable complex with the tin salt system.
[0035] Step 3: Continue stirring the mixture obtained in Step 2 at room temperature for 15 min, and then perform ultrasonic degassing treatment at an ultrasonic frequency of 24 kHz for 50 min to effectively remove dissolved gaseous impurities in the system, further improve the overall uniformity of the electrolyte, and promote the full mixing of each component, finally obtaining an aqueous tin battery electrolyte with uniform appearance and no obvious precipitation.
[0036] Example 2
[0037] Step 1: Measure 6 portions of 1.0 mol / L hydrochloric acid solution and add them to a clean reaction vessel. Then, measure 6 portions of 3.0 mol / L tin methanesulfonate solution and slowly add them to the hydrochloric acid solution. Stir the mixture at room temperature to allow the acidic medium to come into full contact with the tin salt and form a homogeneous and stable acidic tin salt precursor system.
[0038] Step 2: Under continuous stirring, slowly add 5 parts of 7.5 mol / L benzothiazole solution to the acidic tin salt precursor system obtained in Step 1 to fully disperse the benzothiazole additive in the system and form a stable complex with the tin salt system.
[0039] Step 3: Continue stirring the mixture obtained in Step 2 at room temperature for 15 min, and then perform ultrasonic degassing treatment at an ultrasonic frequency of 24 kHz for 50 min to effectively remove dissolved gaseous impurities in the system, further improve the overall uniformity of the electrolyte, and promote the full mixing of each component, finally obtaining an aqueous tin battery electrolyte with uniform appearance and no obvious precipitation.
[0040] Example 3
[0041] Step 1: Measure 6 portions of 1.0 mol / L hydrochloric acid solution and add them to a clean reaction vessel. Then, measure 6 portions of 3.0 mol / L tin methanesulfonate solution and slowly add them to the hydrochloric acid solution. Stir the mixture at room temperature to allow the acidic medium to come into full contact with the tin salt and form a homogeneous and stable acidic tin salt precursor system.
[0042] Step 2: Under continuous stirring, slowly add 7 parts of 7.5 mol / L benzothiazole solution to the acidic tin salt precursor system obtained in Step 1 to fully disperse the benzothiazole additive in the system and form a stable complex with the tin salt system.
[0043] Step 3: Continue stirring the mixture obtained in Step 2 at room temperature for 15 min, and then perform ultrasonic degassing treatment at an ultrasonic frequency of 24 kHz for 50 min to effectively remove dissolved gaseous impurities in the system, further improve the overall uniformity of the electrolyte, and promote the full mixing of each component, finally obtaining an aqueous tin battery electrolyte with uniform appearance and no obvious precipitation.
[0044] Comparative Example 1
[0045] Step 1: Measure 6 portions of 1.0 mol / L hydrochloric acid solution and add them to a clean reaction vessel. Then, measure 6 portions of 3.0 mol / L tin methanesulfonate solution and slowly add them to the hydrochloric acid solution. Stir the mixture at room temperature to allow the acidic medium to come into full contact with the tin salt and form a homogeneous and stable acidic tin salt precursor system.
[0046] Step 2: Continue stirring the mixture obtained in Step 1 at room temperature for 15 min, and then perform ultrasonic degassing treatment at an ultrasonic frequency of 24 kHz for 50 min to effectively remove dissolved gaseous impurities in the system, further improve the overall homogeneity of the electrolyte, and promote the full mixing of the components, finally obtaining a composite electrolyte with a uniform appearance and no obvious precipitation.
[0047] Example 4
[0048] The aqueous tin-metal battery in this embodiment is a Sn∥Sn button-type symmetrical battery. Its assembly process is as follows: The aqueous tin battery electrolytes prepared in Examples 1-3 are used as the battery electrolytes. The components are assembled sequentially in the order of negative electrode shell, gasket, tin foil electrode, glass fiber separator, composite electrolyte, tin foil electrode, and positive electrode shell. During assembly, tweezers are used to gently press each layer of components to ensure full contact and tight adhesion. The assembled battery is then placed in a manual sealing device, and pressure is slowly applied until the sealing structure is pressed and fixed, completing the assembly of the CR2016 type button-type symmetrical battery. The current density is 0.5 mA·cm⁻¹. -2 The surface capacity is 0.5 mAh·cm³. -2 Under certain conditions, constant current charge-discharge tests were conducted to observe its stability.
[0049] Comparative Example 2
[0050] The aqueous tin metal battery in this embodiment is the same as that in Example 4, except that the electrolyte used is the electrolyte prepared in Comparative Example 1 without benzothiazole additive.
[0051] Example 5
[0052] In this embodiment, the aqueous tin-metal battery is a Sn∥Cu button cell. The assembly process is as follows: The composite electrolytes prepared in Examples 1-3 are used as the battery electrolytes. The components are assembled sequentially in the following order: negative electrode shell, gasket, tin foil electrode, glass fiber separator, composite electrolyte, copper electrode, and positive electrode shell. During assembly, tweezers are used to gently press each layer of components to ensure full contact and tight adhesion. The assembled battery is then placed in a manual sealing device, and pressure is slowly applied until the sealing structure is pressed and fixed, completing the assembly of the CR2016 button cell. (The last sentence appears to be incomplete and possibly refers to a measurement or measurement at 1 mA·cm⁻¹.) -2 Current density and 1 mAh·cm -2 Constant current charge-discharge tests were conducted under the condition of areal capacity to observe its coulombic efficiency.
[0053] Comparative Example 3
[0054] The aqueous tin metal battery in this embodiment is the same as that in Example 5, except that the electrolyte used is the electrolyte prepared in Comparative Example 1 without benzothiazole additive.
[0055] Cyclic performance test:
[0056] like Figure 1 As shown, the Sn∥Sn symmetric cell operates at a current density of 0.5 mA·cm⁻¹. -2 The surface capacity is 0.5 mAh·cm³. -2 Under certain conditions, the lifespan exceeds 4000 hours, representing a significant improvement in lifespan.
[0057] like Figure 2 As shown, the Sn∥Sn symmetric cell operates at a current density of 0.5 mA·cm⁻¹. -2 The surface capacity is 0.5 mAh·cm³. -2 Under these conditions, it still exhibits excellent stability even in the later stages of its lifespan, around 4000 hours.
[0058] like Figure 3 As shown, the Sn∥Cu coin cell at 1 mA·cm -2 Current density and 1 mAh·cm -2 Under the condition of surface capacity, it can work stably for nearly 1000 hours with a coulomb efficiency of up to 99.81%.
[0059] In summary, this invention utilizes an acidic environment to treat Sn. 2+ The stability-maintaining effect and the adsorption regulation effect of benzothiazole molecules at the electrode interface improve Sn 2+ The interface transport and deposition behavior promotes the formation of a more uniform and denser deposition layer, reduces particle coarsening, agglomeration and loose accumulation, and inhibits the occurrence of side reactions, thereby improving the reversibility and structural stability of the tin anode, and thus improving the coulombic efficiency, capacity retention and cycle life of aqueous tin metal batteries.
[0060] The descriptions and practices disclosed in this invention are readily apparent and understandable to those skilled in the art, and various modifications and refinements can be made without departing from the principles of this invention. Therefore, any modifications or improvements made without departing from the spirit of this invention should also be considered within the scope of protection of this invention.
Claims
1. A method for preparing an aqueous tin battery electrolyte containing a benzothiazole additive, characterized in that, Includes the following steps: Step 1: Prepare hydrochloric acid solution, tin salt solution and benzothiazole solution respectively. Before use, equilibrate the above raw materials at room temperature to reduce the impact of temperature difference on the uniformity of mixing. Step 2: Measure 6-12 parts of hydrochloric acid solution and add it to a clean reaction vessel. Then measure 6-15 parts of tin salt solution and slowly add it to the hydrochloric acid solution. Stir the mixture at room temperature to allow the acidic medium to come into full contact with the tin salt and form a homogeneous and stable acidic tin salt precursor system. Step 3: Under continuous stirring, slowly add 2-8 parts of benzothiazole solution to the acidic tin salt precursor system obtained in Step 2 to fully disperse the benzothiazole additive in the system and form a stable composite system with the tin salt. Step 4: Continue stirring the mixture obtained in Step 3 at room temperature for 10-30 min, and then perform ultrasonic degassing treatment at an ultrasonic frequency of 12 kHz-36 kHz for 20-50 min to finally obtain a uniform aqueous tin battery electrolyte without precipitation. Step 5: Let the aqueous tin battery electrolyte obtained in Step 4 stand for 6–18 h to further stabilize the system.
2. The method for preparing an aqueous tin battery electrolyte containing benzothiazole additive according to claim 1, characterized in that, In step 1, the tin salt is one or more of tin methanesulfonate, stannous chloride, stannous sulfate, and stannous tetrachloride.
3. The method for preparing an aqueous tin battery electrolyte containing benzothiazole additive according to claim 1, characterized in that, In step 1, the concentration of the hydrochloric acid solution is 0.5–2.5 mol / L, the concentration of the tin salt solution is 0.5–3.5 mol / L, and the concentration of the benzothiazole solution is 5.0–10.0 mol / L.
4. The method for preparing an aqueous tin battery electrolyte containing benzothiazole additive according to claim 1, characterized in that, In step 1, the volume ratio of the hydrochloric acid solution, tin salt solution, and benzothiazole solution is 6-12:6-15:2-8.
5. The application of an aqueous tin battery electrolyte containing benzothiazole additive obtained by the preparation method according to any one of claims 1-4 in an aqueous tin metal battery, characterized in that, The aqueous tin metal battery includes a positive electrode, a negative electrode, a separator, and an aqueous tin battery electrolyte containing benzothiazole additive.
6. The application according to claim 5, characterized in that, The negative electrode is a Sn metal negative electrode with a thickness of 50~300μm.
7. The application according to claim 5, characterized in that, The diaphragm is one or more of glass fiber membrane, non-woven membrane, or porous polymer diaphragm.
8. The application according to claim 5, characterized in that, The positive electrode is an electrode sheet loaded on the current collector. The electrode sheet is formed by pressing a mixture of positive electrode active material, conductive agent and binder into a film.
9. The application according to claim 8, characterized in that, The current collector is one or more of titanium mesh, stainless steel mesh, titanium foil, or stainless steel foil.
10. The application according to claim 8, characterized in that, The adhesive is one or more of polytetrafluoroethylene, polyvinylidene fluoride, sodium carboxymethyl cellulose, and styrene-butadiene rubber.