Polymer solid electrolyte and preparation method and application thereof
By using three-dimensional crosslinking network gel polymer solid electrolyte, the safety and stability of liquid electrolytes in lithium air batteries are solved, and efficient and stable lithium oxygen battery performance is achieved.
Patent Information
- Application Number
- CN202311781665.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2023-12-21
- Publication Date
- 2025-06-24
AI Technical Summary
Because lithium air batteries use liquid electrolytes, there are problems such as electrolytes that are easy to volatilize, pollute the environment, flammable, growth of lithium dendrites, and diffusion of air components, which affects their safety and circulation stability.
A three-dimensional crosslinking network gel polymer solid electrolyte composed of glycidyl methacrylate, crosslinking agent, initiator and lithium-based electrolyte is prepared by ultraviolet curing reaction to form a self-supported solid electrolyte membrane.
It achieves high ionic conductivity, wide voltage window and high lithium negative electrode stability, improving the round-trip efficiency and cycle stability of lithium oxygen batteries.
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Figure CN120199883A_ABST
Abstract
Description
Technical Field
[0001] The present application relates to a polymer solid electrolyte and its preparation method and application, belonging to the technical field of solid-state lithium-oxygen batteries. Background Art
[0002] Currently, fossil fuels including coal, oil, and natural gas meet more than 70% of the world's energy demand, but this has also led to serious problems such as global warming and air pollution. Therefore, electrochemical power sources and energy storage systems play a crucial role in shifting the future energy network model towards clean and renewable energy. Among them, lithium-air batteries have attracted much attention due to their ultra-high theoretical energy density. However, the use of liquid electrolytes and the characteristics of their semi-open systems make lithium-air batteries face many problems such as easy volatilization and environmental pollution of electrolytes, electrolyte decomposition, flammability, lithium dendrite growth, and diffusion of components in the air (such as O2, CO2, H2O, N2) to the lithium negative electrode for reaction, posing a serious threat to their safety and cycle stability. Therefore, it is urgent to develop a safe solid electrolyte-based lithium-air battery. Summary of the Invention
[0003] The object of the present invention is to provide a three-dimensional cross-linked network gel polymer solid electrolyte, which is obtained by curing a mixture containing glycidyl methacrylate, a cross-linking agent, an initiator, and a lithium-based electrolyte. The solid electrolyte prepared has characteristics such as self-supporting, high ionic conductivity, and a wide voltage window. At the same time, it is stable to the lithium negative electrode, and excellent round-trip efficiency and long cycle stability are obtained as the solid electrolyte of a lithium-oxygen battery.
[0004] According to the first aspect of the present application, a polymer solid electrolyte is provided, which is obtained by curing a mixture containing glycidyl methacrylate, a cross-linking agent, an initiator, and a lithium-based electrolyte.
[0005] Optionally, the polymer solid electrolyte is a self-supporting polymer solid electrolyte membrane;
[0006] The thickness of the polymer solid electrolyte is 100 - 200 μm.
[0007] Optionally, the upper limit of the thickness of the polymer solid electrolyte is selected from 200 μm, 180 μm, 160 μm, 140 μm, 120 μm, and the lower limit is selected from 100 μm, 180 μm, 160 μm, 140 μm, 120 μm.
[0008] Optionally, after the glycidyl methacrylate undergoes a curing reaction, poly(glycidyl methacrylate) (PGMA) with a three-dimensional cross-linked polymer network is obtained.
[0009] Optionally, the lithium-based electrolyte includes a lithium salt and an organic solvent; the lithium salt is selected from at least one of LiTFSI and LiClO4;
[0010] The organic solvent is selected from at least one of triethylene glycol dimethyl ether (TEGDME) and DMSO.
[0011] Optionally, the lithium-based electrolyte is selected from at least one of LiTFSI / TEGDME and LiClO4 / DMSO.
[0012] Optionally, the cross-linking agent is selected from one or more of ethylene glycol diacetate and N,N'-methylenebisacrylamide;
[0013] The initiator is selected from one or more of 2,2-diethoxy-1-phenylhexanone, 1-hydroxy-cyclohexyl-phenylmethanone, and 2-hydroxy-2-methyl-1-phenylmethanone.
[0014] Optionally, in the mixture, the mass ratio of the cross-linking agent to glycidyl methacrylate is (2-10):100;
[0015] The mass ratio of the initiator to glycidyl methacrylate is (1-2):100;
[0016] The mass ratio of the lithium-based electrolyte to glycidyl methacrylate is (2-5):1.
[0017] Optionally, the mass ratio of the cross-linking agent to glycidyl methacrylate independently selects any value from 2:100, 3:100, 4:100, 5:100, 6:100, 7:100, 8:100, 9:100, 10:100 or any range value between any two of the above.
[0018] Optionally, the initiator is a photoinitiator, and the mass ratio of the photoinitiator to glycidyl methacrylate independently selects any value from 1:100 and 2:100 or any range value between any two of the above.
[0019] Optionally, the mass ratio of the lithium-based electrolyte to glycidyl methacrylate is any value from 2:1, 3:1, 4:1, 5:1 or any range value between any two of the above;
[0020] According to the second aspect of the present application, a preparation method of the above polymer solid electrolyte is provided, and the preparation method includes:
[0021] Ultraviolet light irradiates the mixture containing glycidyl methacrylate, cross-linking agent, initiator, and lithium-based electrolyte, and a curing reaction is carried out to obtain the polymer solid electrolyte.
[0022] Optionally, the wavelength of the ultraviolet light is 315 - 400 nm; the irradiation time is 10 - 40 min.
[0023] Optionally, the irradiation time is independently selected from any value of 10 min, 20 min, 30 min, 40 min or any range value between any two of the above.
[0024] Optionally, the concentration of the lithium-based electrolyte is 1 M.
[0025] Optionally, the mixture containing glycidyl methacrylate, crosslinking agent, initiator, and lithium-based electrolyte is stirred at 200 - 1000 rpm for 5 h to 24 h.
[0026] As a specific embodiment, the preparation method includes:
[0027] (1) Stir and mix evenly the mixture containing glycidyl methacrylate, crosslinking agent, initiator, and lithium-based electrolyte;
[0028] (2) Pour the mixture obtained in step (1) into a polytetrafluoroethylene / glass mold and irradiate with ultraviolet light to obtain a three-dimensional cross-linked network polymer film.
[0029] As a specific embodiment, the preparation method of the polymer solid electrolyte includes: using glycidyl methacrylate as a monomer, N,N'-methylenebisacrylamide as a crosslinking agent, 2,2-diethoxy-1-phenylhexanone as a photoinitiator, and 1 M LiTFSI / TEGDME as an organic electrolyte, and obtaining the three-dimensional cross-linked network gel polymer electrolyte film through ultraviolet curing.
[0030] The polymer solid electrolyte of the present application, due to its excellent ionic conductivity, wide voltage window, and high stability of the lithium negative electrode, the lithium-oxygen battery assembled with this solid electrolyte has a high round-trip efficiency and long-term stability.
[0031] According to the third aspect of the present application, a lithium-oxygen battery is provided, and the lithium-oxygen battery includes the above polymer solid electrolyte.
[0032] The beneficial effects that the present application can produce include:
[0033] 1) The preparation method of the three-dimensional cross-linked gel polymer solid electrolyte provided by the present application has a simple synthesis method, common required instruments, is simple and easy to implement, and is easy to scale up production.
[0034] 2) The solid electrolyte provided by the present application has excellent ionic conductivity, a wide voltage window, lithium negative electrode protection ability, and excellent charge and discharge performance and stability of the lithium-oxygen battery. Description of the Drawings
[0035] Figure 1 Morphology diagram of Example 1 of this application; Figure 1 The scale in it is 10 μm.
[0036] Figure 2 Electrochemical impedance spectroscopy diagram of Example 4 of this application.
[0037] Figure 3 Linear sweep voltammetry curve of Example 5 of this application.
[0038] Figure 4 Cut-off voltage-time diagram of the lithium symmetric battery assembled in Example 6 of this application at a current density of 0.1 mA cm -2 , where the capacity limit is 0.1 mAh cm -2 .
[0039] Figure 5 Cut-off voltage-time diagram of the lithium-oxygen battery assembled in Example 7 of this application at a current density of 200 mA g -1 , where the capacity limit is 1000 mAh g -1 . Detailed implementation manners
[0040] The present application will be described in detail below with reference to the embodiments, but the present application is not limited to these embodiments.
[0041] Unless otherwise specified, the raw materials in the embodiments of the present application are all purchased through commercial channels.
[0042] For those not specified in the embodiments, they are carried out according to conventional conditions or conditions recommended by the manufacturer. For reagents or instruments whose manufacturers are not specified, they are all conventional products that can be obtained through commercial purchase.
[0043] The morphological characteristics of the samples were analyzed by scanning electron microscopy (SEM), and the analysis instrument was JSM-7900F.
[0044] The electrochemical impedance spectroscopy diagram and linear sweep voltammetry curve were tested using a CHI760E electrochemical workstation (Shanghai Chenhua Instrument Co., Ltd.).
[0045] The constant current charge / discharge test (current density is 200 mA g -1 , the limited capacity is 1000 mAh g -1 ) was carried out using a LAND CT3001A battery system (Wuhan Blue Electronic Co., Ltd.).
[0046] The features and performance of the present invention will be further described in detail below with reference to the embodiments.
[0047] Example 1
[0048] Mix 1 g of glycidyl methacrylate monomer, 0.04 g of N,N'-methylenebisacrylamide crosslinker (MBAM), 0.01 g of 2,2-diethoxy-1-phenylhexanone photoinitiator, and 2 g of 1M LiTFSI / TEGDME organic electrolyte, and stir for 5 h; pour the above mixture into a PTFE mold and irradiate with ultraviolet light (365 nm) for 30 min to obtain a three-dimensional crosslinked network polymer film 1 # , with a thickness of 100 - 200 μm.
[0049] Use a scanning electron microscope to test and analyze the obtained three-dimensional crosslinked network polymer film 1 # The test results are shown in Figure 1 , and it can be seen from Figure 1 that the polymer film shows a dense morphology under the scanning picture.
[0050] Example 2
[0051] Mix 1 g of glycidyl methacrylate monomer, 0.02 g of N,N'-methylenebisacrylamide crosslinker (MBAM), 0.01 g of 1-hydroxy-cyclohexyl-phenylmethanone photoinitiator, and 3 g of 1M LiClO4 / DMSO organic electrolyte, and stir for 10 h; pour the above mixture into a PTFE mold and irradiate with ultraviolet light (365 nm) for 20 min to obtain a three-dimensional crosslinked network polymer film.
[0052] Example 3
[0053] Mix 1 g of glycidyl methacrylate monomer, 0.02 g of ethylene glycol diacetate (EGDA), 0.01 g of 1-hydroxy-cyclohexyl-phenylmethanone photoinitiator, and 3 g of 1M LiTFSI / TEGDME organic electrolyte, and stir for 10 h; pour the above mixture into a PTFE mold and irradiate with ultraviolet light (365 nm) for 15 min to obtain a three-dimensional crosslinked network polymer film.
[0054] Example 4
[0055] Taking sample 1 # as an example, test the ionic conductivity of the polymer solid electrolyte of sample 1 # . The assembly and test method is as follows: use stainless steel sheets as the positive and negative electrodes respectively to assemble a button cell, and conduct an electrochemical impedance spectroscopy test on sample 1 # . It can be seen from Figure 2 that after the test, the ionic conductivity is calculated to be 3.5x10 -4 S cm -1 .
[0056] Example 5
[0057] Taking Sample 1 # as an example, the electrochemical window of the polymer solid electrolyte of Sample 1 # was tested. The assembly and test methods were as follows: A stainless-steel sheet was used as the positive electrode, and a lithium sheet was used as the negative electrode to assemble a button cell. For Sample 1 # , a linear sweep voltammetry curve test was conducted. The test conditions were: voltage range: open-circuit voltage to 6 V, sweep rate: 1 mV s -1 . As can be seen from Figure 3 , Sample 1 # had a wider voltage window than the liquid electrolyte.
[0058] Example 6
[0059] Taking Sample 1 # as an example, a lithium symmetric battery was assembled with the polymer solid electrolyte of Sample 1 # to test its lithium stability. The assembly and test methods were as follows: Lithium sheets were used as the positive and negative electrodes respectively to assemble a button cell. The test conditions were: current density was 0.1 mA cm -2 , and the capacity limit was 0.1 mAh cm -2 . As can be seen from Figure 4 , Sample 1 # had higher lithium stability than the liquid electrolyte, and its lithium symmetric battery could be cycled for more than 1000 h.
[0060] Example 7
[0061] Taking Sample 1 # as an example, a lithium-oxygen battery was assembled with the polymer solid electrolyte of Sample 1 # and its charge-discharge curve was tested. The assembly and test methods were as follows: Carbon paper loaded with about 0.2 mg of commercial ruthenium dioxide was used as the positive electrode, Sample 1 # was used as the solid electrolyte, and a lithium metal sheet was used as the negative electrode to assemble a button cell. A LAND CT3001A battery system was used for constant current charge / discharge testing (current density was 200 mA g -1 , and the limited capacity was 1000 mAh g -1 ). Figure 5 was the charge-discharge curve and cycle stability of the lithium-oxygen battery assembled with this solid electrolyte. It can be seen that it had a very narrow voltage range and extremely long stability.
[0062] As described above, only several embodiments of the present application are provided, and no any form of limitation is imposed on the present application. Although the present application is disclosed with preferred embodiments as above, it is not intended to limit the present application. Any person skilled in the art, without departing from the technical solution of the present application, makes some changes or modifications using the disclosed technical content, which are equivalent to equivalent implementation cases and all fall within the scope of the technical solution.
Claims
1. A polymer solid electrolyte, characterized in that, The polymer solid electrolyte is obtained by curing a mixture containing glycidyl methacrylate, a crosslinking agent, an initiator, and a lithium-based electrolyte solution.
2. The polymer solid electrolyte according to claim 1, wherein The polymer solid electrolyte is a self-supporting polymer solid electrolyte membrane; The thickness of the polymer solid electrolyte is 100 - 200 μm.
3. The polymer solid electrolyte according to claim 1, wherein After the glycidyl methacrylate undergoes a curing reaction, polyglycidyl methacrylate with a three-dimensional crosslinked polymer network is obtained.
4. The polymer solid electrolyte according to claim 1, characterized in that, The lithium-based electrolyte solution includes a lithium salt and an organic solvent; the lithium salt is selected from at least one of LiTFSI and LiClO4; The organic solvent is selected from at least one of triethylene glycol dimethyl ether and dimethyl sulfoxide.
5. The polymer solid electrolyte according to claim 1, wherein The crosslinking agent is selected from one or more of ethylene glycol diacetate and N,N'-methylenebisacrylamide; The initiator is selected from one or more of 2,2 - diethoxy - 1 - phenylhexanone, 1 - hydroxy - cyclohexyl - phenylmethanone, and 2 - hydroxy - 2 - methyl - 1 - phenylpropanone.
6. The polymer solid electrolyte according to claim 1, characterized in that, In the mixture, the mass ratio of the crosslinking agent to glycidyl methacrylate is (2 - 10):100; The mass ratio of the initiator to glycidyl methacrylate is (1 - 2):100; The mass ratio of the lithium-based electrolyte solution to glycidyl methacrylate is (2 - 5):
1.
7. A method for preparing the polymer solid electrolyte according to any one of claims 1 to 6, characterized in that, The preparation method includes: Subjecting the mixture containing glycidyl methacrylate, a crosslinking agent, an initiator, and a lithium-based electrolyte solution to ultraviolet light irradiation to obtain the polymer solid electrolyte through a curing reaction.
8. The preparation method according to claim 7, characterized in that, The wavelength of the ultraviolet light is 315 - 400 nm; the irradiation time is 10 - 40 min.
9. The preparation method according to claim 7, characterized in that, The mixture containing glycidyl methacrylate, a crosslinking agent, an initiator, and a lithium-based electrolyte solution is stirred at a rotation speed of 200 - 1000 rpm for 5 h to 24 h.
10. A lithium-oxygen battery, characterized in that, The lithium-oxygen battery includes the polymer solid electrolyte according to any one of claims 1 to 6.