High modulus quasi-solid electrolyte for aqueous zinc ion batteries and methods of making the same

Abstract

The application discloses a high modulus quasi-solid electrolyte for aqueous zinc ion batteries and a preparation method thereof. The high modulus quasi-solid electrolyte is a mixture of a polymerization reaction product of polyethylene glycol methyl ether methacrylate, a hydrophobic monomer and a crosslinking agent and a zinc salt aqueous solution. The preparation method comprises the following steps: uniformly mixing the polyethylene glycol methyl ether methacrylate, the hydrophobic monomer, the crosslinking agent and a photoinitiator, irradiating under ultraviolet light for 0.5-3 hours to obtain a precursor of the quasi-solid electrolyte, and then soaking the precursor in a zinc salt aqueous solution with a certain concentration for 6-36 hours to obtain the quasi-solid electrolyte. The prepared quasi-solid electrolyte has a higher elastic modulus and good conductivity, can significantly inhibit zinc dendrite growth, does not use organic solvents in the preparation process, is green and environmentally friendly, is beneficial to large-scale production, and has certain practical significance for improving the electrochemical performance of zinc ion batteries and promoting large-scale application of the zinc ion batteries.

Description

Technical Field

[0001] This invention relates to the field of aqueous zinc-ion battery energy storage technology, specifically to a high-modulus quasi-solid-state electrolyte for aqueous zinc-ion batteries and its preparation method. Background Technology

[0002] With the rapid development of new energy technologies, especially the expanding markets for electric vehicles and portable electronic devices, the demand for high-performance and high-safety batteries is increasing. While traditional liquid electrolyte batteries offer high energy density and ion conductivity, they suffer from safety hazards such as gas expansion and leakage, and have poor environmental adaptability. Aqueous zinc-ion batteries, on the other hand, offer advantages such as high safety, abundant raw material reserves, and environmental friendliness, making them promising candidates for large-scale green energy storage and possessing significant market potential.

[0003] However, the development of quasi-solid-state electrolytes for aqueous zinc-ion batteries still faces many unresolved issues. Most zinc-ion quasi-solid-state electrolytes are hydrogel materials, which have insufficient modulus, making them prone to damage. Dendrite formation on the zinc foil surface can lead to internal short circuits, resulting in insufficient safety and hindering the large-scale application of zinc-ion batteries. Summary of the Invention

[0004] The purpose of this invention is to address the technical problems of low modulus, easy damage, and difficulty in suppressing dendrite growth in current aqueous zinc-ion quasi-solid electrolytes, and to provide a high modulus quasi-solid electrolyte for aqueous zinc-ion batteries and its preparation method.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0006] This invention provides a high-modulus quasi-solid-state electrolyte for aqueous zinc-ion batteries. The high-modulus quasi-solid-state electrolyte is a mixture of a precursor prepared from polyethylene glycol methyl ether methacrylate, a hydrophobic monomer, and a crosslinking agent under photoinitiation, and an aqueous zinc salt solution. This invention utilizes the precursor obtained by photoinitiated polymerization of polyethylene glycol methyl ether methacrylate, a hydrophobic monomer, and a crosslinking agent to obtain the quasi-solid-state electrolyte after immersion in a zinc salt solution. This preparation method is simple, uses readily available raw materials, requires no organic solvents, and yields a quasi-solid-state electrolyte with extremely high elastic modulus and good conductivity, showing great application potential in the field of aqueous zinc-ion energy storage.

[0007] Furthermore, the polyethylene glycol methyl ether methacrylate has one or more molecular weights of 300, 450, 500, and 950.

[0008] Furthermore, the hydrophobic monomer is one or more of styrene, benzyl acrylate, benzyl methacrylate, methyl methacrylate, ethyl methacrylate, n-hexyl methacrylate, dodecyl methacrylate, octadecyl methacrylate, and 2-ethylhexyl methacrylate.

[0009] Furthermore, the crosslinking agent is one or more of N,N'-methylenebisacrylamide, diethylene glycol dimethacrylate, and polyethylene glycol dimethacrylate.

[0010] Furthermore, the photoinitiator is one or more of the following: 2-hydroxy-2-methyl-1-phenyl-1-propanone (1173 photoinitiator), phenyl bis(2,4,6-trimethylbenzoyl)phosphine oxide (819 photoinitiator), 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylphenylpropanone (2959 photoinitiator), 1-hydroxy-cyclohexyl-phenyl ketone (184 photoinitiator), 2,4,6-trimethylbenzoyl diphenylphosphine oxide (TPO), ethyl 2,4,6-trimethylbenzoylphosphonate (TPO-L), benzoin dimethyl ether (DMPA), phenyl bis(2,4,6-trimethylbenzoyl)phosphine oxide (819 photoinitiator), and 2-methyl-1-[4-methylthiophenyl]-2-morpholino-1-propanone (907 photoinitiator).

[0011] Furthermore, the zinc salt in the zinc salt aqueous solution is one or more of zinc chloride, zinc sulfate, zinc trifluoromethanesulfonate, zinc acetate, zinc perchlorate, and zinc bis(trifluoromethanesulfonyl)imide.

[0012] The present invention also provides a method for preparing the high-modulus quasi-solid-state electrolyte for aqueous zinc-ion batteries, the method comprising: mixing polyethylene glycol methyl ether methacrylate, hydrophobic monomer, crosslinking agent and photoinitiator uniformly and injecting the mixture into a mold, initiating polymerization under ultraviolet light to obtain a precursor; immersing the precursor in an aqueous zinc salt solution to obtain the high-modulus quasi-solid-state electrolyte.

[0013] Further, the molar ratio of polyethylene glycol methyl ether methacrylate, hydrophobic monomer, crosslinking agent and photoinitiator is 1:0.5-40:0.001-0.01:0.01-0.02; preferably, the molar ratio of polyethylene glycol methyl ether methacrylate, hydrophobic monomer, crosslinking agent and photoinitiator is 1:10:0.005:0.02; preferably, the mixing time is 10-40 min.

[0014] Furthermore, the ultraviolet light irradiation time is 0.5 to 3 hours.

[0015] Furthermore, the concentration of the zinc salt aqueous solution is 0.5–3 M; preferably, the soaking time is 6–36 hours.

[0016] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0017] This invention provides a high-modulus quasi-solid-state electrolyte for aqueous zinc-ion batteries and its preparation method. A quasi-solid-state electrolyte precursor for aqueous zinc-ion batteries is prepared through simple free radical polymerization, and the high-modulus quasi-solid-state electrolyte is prepared by solution immersion. Due to the aggregation and hardening of hydrophobic units, it can effectively withstand external forces. This material has an ultra-high elastic modulus and inhibits the formation of zinc dendrites. Based on the movement of a large number of polyethylene glycol segments, Zn... 2+ This electrolyte exhibits excellent conductivity and rapid transport capabilities. The preparation method provided by this invention is simple, effective, and low-cost, facilitating large-scale production and offering valuable insights for promoting the application of zinc-ion batteries in the energy storage field. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the quasi-solid electrolyte prepared according to an embodiment of the present invention;

[0019] Figure 2 These are optical images of the quasi-solid electrolyte prepared in Example 3 of this invention before and after hardening, showing the weight being lifted.

[0020] Figure 3 These are optical images showing the changes in volume, softness, and conductivity of the quasi-solid electrolyte prepared in Example 6 of this invention before and after immersion.

[0021] Figure 4 This is the stress-strain curve of the quasi-solid electrolyte prepared in Example 6 of this invention after immersion. Detailed Implementation

[0022] The present invention will be further described in detail below with reference to the embodiments, but the implementation of the present invention is not limited thereto.

[0023] It should be noted that the purpose of the following embodiments is to enable those skilled in the art to understand the content of the present invention and implement it accordingly, and should not be used to limit the scope of protection of the present invention. All equivalent changes or modifications made in accordance with the spirit and essence of the present invention should be covered within the scope of protection of the present invention.

[0024] In the following detailed description, specific embodiments of the present invention will be given with reference to the accompanying drawings. Based on these detailed descriptions, those skilled in the art will be able to clearly understand and implement the present invention. Without departing from the principles of the present invention, features in the various embodiments may be combined to obtain new implementations, or certain features in some embodiments may be substituted to obtain other preferred implementations.

[0025] Example 1

[0026] In this embodiment, the high-modulus quasi-solid electrolyte is polyethylene glycol methyl ether methacrylate (M... n =500), a mixture of hydrophobic monomer, crosslinking agent, photoinitiator, zinc salt and water, specifically using methyl methacrylate as the hydrophobic monomer, diethylene glycol dimethacrylate as the crosslinking agent, 2-hydroxy-2-methyl-1-phenyl-1-propanone as the photoinitiator, and zinc sulfate as the zinc salt.

[0027] The preparation method of the high-modulus quasi-solid electrolyte in this embodiment includes the following specific steps:

[0028] Add 0.5g of polyethylene glycol methyl ether methacrylate, 1.5g of methyl methacrylate, 0.02g of diethylene glycol dimethacrylate, and 0.01g of 2-hydroxy-2-methyl-1-phenyl-1-propanone to a flask equipped with a stirrer. Mix thoroughly and pour into a rectangular mold. Irradiate under ultraviolet light for 2 hours. After the reaction is complete, soak the obtained sample in a 1M zinc sulfate aqueous solution for 6 hours to obtain a high-modulus quasi-solid electrolyte.

[0029] Example 2

[0030] In this embodiment, the high-modulus quasi-solid electrolyte is polyethylene glycol methyl ether methacrylate (M... n =500), a mixture of hydrophobic monomer, crosslinking agent, photoinitiator, zinc salt and water, specifically using ethyl methacrylate as the hydrophobic monomer, diethylene glycol dimethacrylate as the crosslinking agent, phenyl bis(2,4,6-trimethylbenzoyl)phosphine oxide as the photoinitiator, and zinc perchlorate as the zinc salt.

[0031] The preparation method of the high-modulus quasi-solid electrolyte in this embodiment includes the following specific steps:

[0032] Add 0.95 g of polyethylene glycol methyl ether methacrylate, 1.14 g of ethyl methacrylate, 0.021 g of diethylene glycol dimethacrylate, and 0.021 g of phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide to a flask equipped with a stirrer. After mixing thoroughly, pour the mixture into a rectangular mold and irradiate under ultraviolet light for 1 hour. After the reaction is complete, soak the resulting sample in a 1M zinc perchlorate aqueous solution for 12 hours to obtain a high-modulus quasi-solid electrolyte.

[0033] Example 3

[0034] In this embodiment, the high-modulus quasi-solid electrolyte is polyethylene glycol methyl ether methacrylate (M... n=300), a mixture of hydrophobic monomer, crosslinking agent, photoinitiator, zinc salt and water, specifically using styrene as the hydrophobic monomer, N,N'-methylenebisacrylamide as the crosslinking agent, 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylphenylacetone as the photoinitiator, and zinc acetate as the zinc salt.

[0035] The preparation method of the high-modulus quasi-solid electrolyte in this embodiment includes the following specific steps:

[0036] Add 3g of polyethylene glycol methyl ether methacrylate, 2.08g of styrene, 0.005g of N,N'-methylenebisacrylamide, and 0.05g of 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylphenylacetone to a flask equipped with a stirrer. After mixing thoroughly, pour the mixture into a rectangular mold and irradiate under ultraviolet light for 3 hours. After the reaction is complete, soak the resulting sample in a 1M zinc acetate aqueous solution for 24 hours to obtain a high-modulus quasi-solid electrolyte. Optical images of the prepared quasi-solid electrolyte before and after hardening with a weight are shown below. Figure 2 As shown, from Figure 2 It can be seen that the polymer before hardening is relatively soft and cannot lift heavy objects even after undergoing significant deformation; while the electrolyte after hardening can easily lift a 2kg weight, which directly demonstrates the effect of water-induced hardening.

[0037] Example 4

[0038] In this embodiment, the high-modulus quasi-solid electrolyte is polyethylene glycol methyl ether methacrylate (M... n =450), a mixture of hydrophobic monomer, crosslinking agent, photoinitiator, zinc salt and water, specifically using benzyl acrylate as the hydrophobic monomer, N,N'-methylenebisacrylamide as the crosslinking agent, 2,4,6-trimethylbenzoyl diphenylphosphine oxide as the photoinitiator, and zinc bis(trifluoromethanesulfonyl)imide as the zinc salt.

[0039] The preparation method of the high-modulus quasi-solid electrolyte in this embodiment includes the following specific steps:

[0040] Add 0.9 g of polyethylene glycol methyl ether methacrylate, 1.62 g of benzyl acrylate, 0.013 g of N,N'-methylenebisacrylamide, and 0.013 g of 2,4,6-trimethylbenzoyl diphenylphosphine oxide to a flask equipped with a stirrer. After mixing thoroughly, pour the mixture into a rectangular mold and irradiate under ultraviolet light for 0.5 hours. After the reaction is complete, immerse the resulting sample in a 1 M aqueous solution of zinc bis(trifluoromethanesulfonyl)imide for 24 hours to obtain a high-modulus quasi-solid electrolyte.

[0041] Example 5

[0042] In this embodiment, the high-modulus quasi-solid electrolyte is polyethylene glycol methyl ether methacrylate (M... n=950), a mixture of hydrophobic monomer, crosslinking agent, photoinitiator, zinc salt and water, specifically using benzyl methacrylate as the hydrophobic monomer, polyethylene glycol dimethacrylate as the crosslinking agent, 1-hydroxy-cyclohexyl-phenyl ketone as the photoinitiator, and zinc trifluoromethanesulfonate as the zinc salt.

[0043] The preparation method of the high-modulus quasi-solid electrolyte in this embodiment includes the following specific steps:

[0044] Add 0.95g of polyethylene glycol methyl ether methacrylate, 1.76g of benzyl methacrylate, 0.027g of polyethylene glycol dimethacrylate, and 0.014g of 1-hydroxy-cyclohexyl-phenyl ketone to a flask equipped with a stirrer. Mix thoroughly and pour into a rectangular mold. Irradiate under ultraviolet light for 3 hours. After the reaction is complete, soak the obtained sample in a 1M aqueous solution of zinc trifluoromethanesulfonate for 24 hours to obtain a high-modulus quasi-solid electrolyte.

[0045] Example 6

[0046] In this embodiment, the high-modulus quasi-solid electrolyte is polyethylene glycol methyl ether methacrylate (M... n =500), a mixture of hydrophobic monomer, crosslinking agent, photoinitiator, zinc salt and water, specifically using dodecyl methacrylate as the hydrophobic monomer, polyethylene glycol dimethacrylate as the crosslinking agent, ethyl 2,4,6-trimethylbenzoylphosphonate as the photoinitiator, and zinc sulfate as the zinc salt.

[0047] The preparation method of the high-modulus quasi-solid electrolyte in this embodiment includes the following specific steps:

[0048] Add 0.5 g of polyethylene glycol methyl ether methacrylate, 2.54 g of dodecyl methacrylate, 0.03 g of polyethylene glycol dimethacrylate, and 0.06 g of ethyl 2,4,6-trimethylbenzoylphosphonate to a flask equipped with a stirrer. After thorough mixing, pour the mixture into a rectangular mold and irradiate under ultraviolet light for 0.5 hours. After the reaction is complete, immerse the resulting sample in an aqueous zinc sulfate solution for 12 hours to obtain a high-modulus quasi-solid electrolyte. Optical images showing the changes in volume, softness, and conductivity of the prepared quasi-solid electrolyte before and after immersion are shown below. Figure 3 As shown, from Figure 3 It can be seen that the polymer increases in volume due to swelling after being soaked in the solution, and the hardening effect of the soaked sample is obvious; the dry sample is not conductive and cannot be connected to the circuit, while the soaked sample contains ions and can be connected to the circuit, and the red LED is lit. Figure 4 The stress-strain curve of this sample is shown. The tensile strength of the quasi-solid electrolyte is as high as 5 MPa and the Young's modulus is 120 MPa, which is much higher than that of common quasi-solid electrolytes.

[0049] Example 7

[0050] In this embodiment, the high-modulus quasi-solid electrolyte is polyethylene glycol methyl ether methacrylate (M... n =450), a mixture of hydrophobic monomer, crosslinking agent, photoinitiator, zinc salt and water, specifically using octadecyl methacrylate as the hydrophobic monomer, N,N'-methylenebisacrylamide as the crosslinking agent, 2-hydroxy-2-methyl-1-phenyl-1-propanone as the photoinitiator, and zinc sulfate as the zinc salt.

[0051] The preparation method of the high-modulus quasi-solid electrolyte in this embodiment includes the following specific steps:

[0052] Add 0.45 g of polyethylene glycol methyl ether methacrylate, 3.39 g of octadecyl methacrylate, 0.0384 g of N,N'-methylenebisacrylamide, and 0.0182 g of 2-hydroxy-2-methyl-1-phenyl-1-propanone to a flask equipped with a stirrer. After mixing thoroughly, pour the mixture into a rectangular mold and irradiate under ultraviolet light for 1 hour. After the reaction is complete, soak the resulting sample in an aqueous solution of zinc sulfate for 36 hours to obtain a high-modulus quasi-solid electrolyte.

[0053] Example 8

[0054] In this embodiment, the high-modulus quasi-solid electrolyte is polyethylene glycol methyl ether methacrylate (M... n =450), a mixture of hydrophobic monomer, crosslinking agent, photoinitiator, zinc salt and water, specifically using 2-ethylhexyl methacrylate as the hydrophobic monomer, N,N'-methylenebisacrylamide as the crosslinking agent, 2-hydroxy-2-methyl-1-phenyl-1-propanone as the photoinitiator, and zinc sulfate as the zinc salt.

[0055] The preparation method of the high-modulus quasi-solid electrolyte in this embodiment includes the following specific steps:

[0056] Add 0.3 g of polyethylene glycol methyl ether methacrylate, 5.95 g of 2-ethylhexyl methacrylate, 0.0063 g of N,N'-methylenebisacrylamide, and 0.0625 g of 2-hydroxy-2-methyl-1-phenyl-1-propanone to a flask equipped with a stir bar. After mixing thoroughly, pour the mixture into a rectangular mold and irradiate under ultraviolet light for 0.5 hours. After the reaction is complete, soak the resulting sample in an aqueous zinc sulfate solution for 24 hours to obtain a high-modulus quasi-solid electrolyte.

[0057] The above embodiments are only for illustrating the technical concept and features of the present invention, and are intended to enable those skilled in the art to understand the content of the present invention and implement it accordingly. They should not be used to limit the scope of protection of the present invention. All equivalent changes or modifications made in accordance with the spirit and essence of the present invention should be covered within the scope of protection of the present invention.

[0058] The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the embodiments described above. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention shall be considered equivalent substitutions and shall be included within the protection scope of the present invention.

Claims

1. A high modulus quasi-solid-state electrolyte for aqueous zinc-ion batteries, characterized in that, The high modulus quasi-solid electrolyte is a mixture of a precursor prepared from polyethylene glycol methyl ether methacrylate, a hydrophobic monomer and a crosslinking agent under the initiation of a photoinitiator and an aqueous zinc salt solution. The hydrophobic monomer is one or more of styrene, benzyl acrylate, benzyl methacrylate, methyl methacrylate, ethyl methacrylate, n-hexyl methacrylate, dodecyl methacrylate, octadecyl methacrylate and 2-ethylhexyl methacrylate.

2. The high modulus quasi-solid electrolyte for aqueous zinc ion batteries of claim 1, wherein, The polyethylene glycol methyl ether methacrylate has one or more of a molecular weight of 300, 450, 500 and 950.

3. The high modulus quasi-solid electrolyte for aqueous zinc ion batteries of claim 1, wherein, The crosslinking agent is one or more of N,N'-methylenebisacrylamide, diethylene glycol dimethacrylate and polyethylene glycol dimethacrylate.

4. The high modulus quasi-solid electrolyte for aqueous zinc ion batteries of claim 1, wherein, The photoinitiator is one or more of 2-hydroxy-2-methyl-1-phenyl-1-propanone, phenyl bis(2,4,6-trimethylbenzoyl)phosphine oxide, 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone, 1-hydroxy-cyclohexyl-phenyl ketone, 2,4,6-trimethylbenzoyl diphenyl phosphine oxide, ethyl 2,4,6-trimethylbenzoyl phosphinate, benzoin dimethyl ether, phenyl bis(2,4,6-trimethylbenzoyl)phosphine oxide and 2-methyl-1-[4-methylthiophenyl]-2-morpholinopropanone.

5. The high modulus quasi-solid electrolyte for aqueous zinc ion batteries of claim 1, wherein, The zinc salt in the aqueous zinc salt solution is one or more of zinc chloride, zinc sulfate, zinc trifluoromethanesulfonate, zinc acetate, zinc perchlorate and bis(trifluoromethylsulfonyl)imide zinc.

6. The method for the preparation of high modulus quasi-solid electrolyte for aqueous zinc ion batteries according to any one of claims 1 to 5, characterized in that, The preparation method comprises: The polyethylene glycol methyl ether methacrylate, the hydrophobic monomer, the crosslinking agent and the photoinitiator are mixed uniformly, and then the mixture is injected into a mold to initiate polymerization under the irradiation of ultraviolet light to obtain the precursor; and the precursor is soaked in an aqueous zinc salt solution to obtain the high modulus quasi-solid electrolyte.

7. The method of claim 6, wherein the method is characterized by, The molar ratio of the polyethylene glycol methyl ether methacrylate, the hydrophobic monomer, the crosslinking agent and the photoinitiator is 1:0.5-40:0.001-0.01:0.01-0.

02.

8. The method of claim 7, wherein the method is characterized by, The molar ratio of the polyethylene glycol methyl ether methacrylate, the hydrophobic monomer, the crosslinking agent and the photoinitiator is 1:10:0.005:0.

02. The mixing time is 10-40 min.

9. The method of claim 6, wherein the high modulus quasi-solid electrolyte for aqueous zinc ion batteries is prepared by, The irradiation time of the ultraviolet light is 0.5-3 hours.

10. The method of claim 6, wherein the high modulus quasi-solid electrolyte for aqueous zinc ion batteries is prepared by, The concentration of the aqueous zinc salt solution is 0.5-3 M. The soaking time is 6-36 hours.

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