Resin solid electrolyte having a directional pore structure and method for preparing the same

Abstract

The application discloses a resin solid electrolyte with a directional pore structure and a preparation method thereof. The resin solid electrolyte is used as a main raw material, a certain amount of a magnetic response material is added, and the resin solid electrolyte is introduced into a closed mold together with resin monomers and a curing agent to be cured. The curing process is controlled through a magnetic field. After curing, the resin solid electrolyte with the directional pore structure is obtained through etching. After the resin solid electrolyte is soaked in an electrolyte containing lithium salt and a carbonate solvent, a high ionic conductivity can be obtained. The resin solid electrolyte with the directional pore structure prepared by the method has good mechanical properties and can be industrially produced.

Description

Technical Field

[0001] This invention belongs to the field of solid electrolytes, specifically relating to a resin solid electrolyte with a directional pore structure and its preparation method. Background Technology

[0002] Structural energy storage composite materials, as a new type of structural and functional integrated composite material, not only meet the mechanical load-bearing performance requirements, but also have the function of storing and releasing electrical energy, realizing the integration of structural load-bearing and storage / discharge functions. They have the characteristics of low density, high strength and high energy storage efficiency, and have now become a promising new energy storage technology with the potential to be applied to the structures of equipment in aviation, aerospace, transportation and other fields.

[0003] The energy storage performance and mechanical properties of structural energy storage composite materials are important evaluation indicators. Since structural energy storage composite materials are typically composed of carbon fibers as electrode materials, glass fibers as membrane materials, and a polymer matrix with structural support and ion conductivity as a solid electrolyte, the solid electrolyte plays a crucial role. It not only serves to bond the carbon and glass fibers together to achieve mechanical support, but also needs to have a porous structure to allow conductive ions to pass through the composite material, thus achieving energy storage. Therefore, the preparation of solid electrolytes with porous structures and strong mechanical support properties is of great significance for the practical application of structural energy storage materials.

[0004] The traditional method for preparing porous solid electrolytes is phase separation. However, the mechanical properties of structural energy storage materials formed by resin solid electrolytes with conventional microporous structures prepared by this method will be significantly reduced, and the ion transport path will be limited, resulting in low energy storage capacity. Therefore, there is a need for preparation technology of resin solid electrolyte materials with novel pore structures to improve the mechanical properties and energy storage capacity of structural energy storage composite materials.

[0005] This invention provides a novel preparation technique for resin solid electrolytes with directional pore structures. By using a magnetic field to control the directional pore structure of the resin solid electrolyte, it is possible to maintain certain mechanical properties of the resin while constructing an ion channel structure. Summary of the Invention

[0006] The purpose of this invention is to provide a resin solid electrolyte with a directional pore structure and its preparation method.

[0007] To achieve the above objectives, the present invention provides the following technical solution: A method for preparing a resin solid electrolyte with a directional pore structure, the process of which is as follows: (1) Add magnetic response material to epoxy resin monomer, soak for more than 10 hours, and stir to obtain nano magnetic response material / epoxy resin nano composite material suspension. (2) Add curing agent to the suspension in step (1), stir at room temperature first, then stir at 60~90℃ for 2 h~3 h, pour the completely mixed suspension into the mold, and cure at 100~115℃ under a magnetic field strength of 10 mT~400 mT for 2~8 h, and cool naturally to room temperature. (3) Demold, then cure at 120~150℃ for 2~8 h, and cool naturally to room temperature; (4) Place the sample from step (3) in the etching solution for 20-40 hours, remove it, and freeze-dry it; (5) Immerse the freeze-dried sample in an ion electrolyte solution and then remove it to obtain the final product.

[0008] Further, in step (1), the epoxy resin monomer is one or a mixture of two or more of bisphenol A type epoxy resin, bisphenol F type epoxy resin and bisphenol S type epoxy resin in any proportion.

[0009] Further, in step (1), the magnetic response material is one or more of nano-iron oxide, nano-iron and nano-cobalt in any proportion.

[0010] Furthermore, in step (1), the mass of the added magnetic response material accounts for 0.5% to 10% of the total mass of the resin monomer and curing agent.

[0011] Further, in step (2), the curing agent is one or more of PACM, AIBN, and EK3402 in any proportion, and the mass ratio of epoxy resin monomer to curing agent is 1:(0.2~0.3). Furthermore, in step (2), the mold material is one or more of polytetrafluoroethylene, aluminum alloy and copper alloy in any proportion.

[0012] Further, in step (4), the etching solution is a mixture of one or more of sulfuric acid, hydrochloric acid and sulfonic acid in any proportion, with an acid concentration range of 1 mol / L to 7 mol / L.

[0013] Furthermore, in step (5), the ionic electrolyte used includes, but is not limited to, LB-266, LB-632 and LX-031, and the soaking time is not less than 10 hours.

[0014] The resin solid electrolyte with a directional pore structure prepared in this way has an ionic conductivity ranging from 0.1 mS / cm. -1 ~3.0 mS cm -1The mechanical tensile strength ranges from 40 MPa to 85 MPa under the ASTM D638 standard test.

[0015] This invention provides a novel technique for preparing resin solid electrolytes, which uses a magnetic field to control the fabrication of directional porous structures suitable for ion transport. Compared to resin solid electrolytes prepared by phase separation methods, the resin solid electrolyte with directional porous structures obtained by this invention possesses both certain mechanical properties and high ionic conductivity. Attached Figure Description

[0016] Figure 1 This is a scanning electron microscope image of the pore structure prepared in Example 1; Figure 2 The image shows the AC impedance spectrum of the resin solid electrolyte prepared in Example 1. Figure 3 The displacement-stretch curves of (a) bisphenol F type epoxy resin and (b) the prepared resin solid electrolyte in Example 1 are shown. Detailed Implementation

[0017] The present invention will be further described below with reference to the accompanying drawings, but the scope of protection of the present invention is not limited thereto.

[0018] Example 1 A method for preparing a resin solid electrolyte with a directional pore structure, comprising the following steps: (1) Weigh 2% of nano-ferric oxide with an average particle size of about 20 nm into a beaker and impregnate it with bisphenol F epoxy resin (Epon-862, Hexion) for 12 h under conditions without external interference. Then, mechanically stir at 30 °C to obtain a nano-ferric oxide / epoxy resin nanocomposite suspension.

[0019] (2) Add epoxy resin curing agent EK3402 to the above suspension at a resin / curing agent mass ratio of 100 / 26.5, and then continue mechanical stirring at 30 ℃ for 1 h. Then, heat the water bath to 70 ℃ and stir for 3 h. Pour the completely mixed suspension into a mold and cure it at 110 ℃ under a magnetic field strength of 80 mT for 6 h. Then, let it cool naturally to room temperature.

[0020] (3) After that, the cured sample was taken out of the mold and placed in a 120 ℃ oven for 5 h to cure, and then cooled naturally to room temperature.

[0021] (4) After etching the cured sample in a 5 mol / L sulfuric acid solution for 30 h, it was freeze-dried at -52℃ and 10 Pa for 12 h to prepare a resin solid electrolyte with a directional pore structure and a thickness of 1 mm.

[0022] Depend on Figure 1 The scanning electron microscope images of the resin solid electrolyte prepared in the examples show that the pore structure prepared under these conditions is oriented, and the width of the formed pores is about 1 μm to 2 μm.

[0023] (5) The resin solid electrolyte from step (4) was immersed in lithium hexafluorophosphate ion liquid electrolyte (LB-266, 1M LiPF6 in DEC:DMC:EC=1:1:1 Vol% with 1% VC) for 12 hours. After immersion, the solid electrolyte immersed in the ion liquid electrolyte was placed in a button cell. Two stainless steel sheets were used as the positive and negative electrodes, respectively, and a spring was placed in the cell. The cells were then pressed into a button cell. The AC impedance spectrum of the resin solid electrolyte was tested. The results are detailed in [link to relevant documentation]. Figure 2 ,pass Figure 2 The AC impedance spectroscopy results of the resin solid electrolyte prepared in the examples can be used to calculate that the ionic conductivity of the resin solid electrolyte prepared under these conditions is 0.35 mS / cm, and the calculation formula is as follows: ,in σ Indicates ionic conductivity. R e The impedance was measured to be 240Ω. S The sample area is 1.12 cm². 2 , d The sample thickness is 0.094 cm.

[0024] Depend on Figure 3 The displacement-stretch curve of the resin solid electrolyte prepared in step (4) of Example 1 is obtained by... Figure 3 The tensile strength of the resin solid electrolyte prepared in this way is 68.2 MPa, which is only slightly lower than the tensile strength of the raw material bisphenol F epoxy resin (83.9 MPa).

[0025] Example 2 A method for preparing a resin solid electrolyte with a directional pore structure, comprising the following steps: (1) Weigh 2% of nano-ferric oxide with an average particle size of about 20 nm into a beaker and impregnate it with bisphenol F epoxy resin (Epon-862, Hexion) for 12 h under conditions without external interference. Then, mechanically stir at 30 °C to obtain a nano-ferric oxide / epoxy resin nanocomposite suspension.

[0026] (2) Add epoxy curing agent EK3402 to the above suspension at a resin / curing agent mass ratio of 100 / 26.5, and then continue mechanical stirring at 30°C for 1 h. Then, heat the water bath to 70°C and stir for 2 h. Pour the completely mixed suspension into a special mold and cure it at 110°C under a magnetic field strength of 50 mT for 6 h. Then, let it cool naturally to room temperature.

[0027] (3) After that, the cured sample was taken out of the mold and placed in a 120 ℃ oven for 5 h to cure, and then cooled naturally to room temperature.

[0028] (4) After etching the cured sample in a 5 mol / L sulfuric acid solution for 30 h, it was freeze-dried at -52℃ and 10 Pa for 12 h to prepare a resin solid electrolyte with a directional pore structure and a thickness of 1 mm.

[0029] (5) Soak the resin solid electrolyte from step (4) in lithium hexafluorophosphate liquid electrolyte (LB-266, 1MLiPF6in DEC:DMC:EC=1:1:1 Vol% with 1%VC) for 12 hours, then remove it to obtain the product.

[0030] The tensile strength of the resin solid electrolyte obtained in step (4) of this embodiment is 67.5 MPa, and the ionic conductivity of the sample in step (5) is 0.23 mS / cm.

[0031] Example 3 A method for preparing a resin solid electrolyte with a directional pore structure, comprising the following steps: (1) Weigh 3% of nano-ferric oxide with an average particle size of about 20 nm into a beaker and impregnate it with bisphenol F epoxy resin (Epon-862, Hexion) for 12 h under no external interference. Then, mechanically stir at 30 °C to obtain a nano-ferric oxide / epoxy resin nanocomposite suspension.

[0032] (2) Add epoxy curing agent EK3402 to the above suspension at a resin / curing agent mass ratio of 100 / 26.5, and then continue mechanical stirring at 30 ℃ for 1 h. Then, heat the water bath to 70 ℃ and stir for 3 h. Pour the completely mixed suspension into a special mold and cure it at 110 ℃ under a magnetic field strength of 80 mT for 6 h. Then, let it cool naturally to room temperature.

[0033] (3) After that, the cured sample was taken out of the mold and placed in a 120 ℃ oven for 5 h to cure, and then cooled naturally to room temperature.

[0034] (4) The cured sample was etched in a 5 mol / L sulfuric acid solution for 30 h and then freeze-dried to prepare a resin solid electrolyte with a directional pore structure and a thickness of 1 mm. (5) Soak the resin solid electrolyte from step (4) in lithium hexafluorophosphate liquid electrolyte (LB-266, 1MLiPF6in DEC:DMC:EC=1:1:1 Vol% with 1%VC) for 12 hours, then remove it to obtain the product.

[0035] The tensile strength of the resin solid electrolyte obtained in step (4) of this embodiment is 77.1 MPa, and the ionic conductivity of the sample in step (5) is 0.56 mS / cm.

[0036] The above description of the embodiments is provided to enable those skilled in the art to understand and apply the present invention. It will be apparent to those skilled in the art that various modifications can be easily made to these embodiments, and the general principles described herein can be applied to other embodiments without inventive effort. Therefore, the present invention is not limited to the embodiments described herein, and any improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the invention should be within the protection scope of the present invention.

Claims

1. A method for preparing a resin solid electrolyte with a directional pore structure, characterized in that, The process is as follows: (1) Add magnetic response material to epoxy resin monomer, soak for more than 10 hours, and stir to obtain nano magnetic response material / epoxy resin nano composite material suspension. (2) Add curing agent to the suspension in step (1), stir at room temperature first, then stir at 60~90℃ for 2 h~3 h, pour the completely mixed suspension into the mold, and cure at 100~115℃ under a magnetic field strength of 10 mT~400 mT for 2~8 h, and cool naturally to room temperature. (3) Demold, then cure at 120~150℃ for 2~8 h, and cool naturally to room temperature; (4) Place the sample from step (3) in the etching solution for 20-40 hours, remove it, and freeze-dry it; (5) Immerse the freeze-dried sample in an ion electrolyte solution and then remove it to obtain the final product.

2. The method for preparing the resin solid electrolyte with oriented channel structure as described in claim 1, characterized in that, In step (1), the epoxy resin monomer is one or a mixture of two or more of bisphenol A type epoxy resin, bisphenol F type epoxy resin and bisphenol S type epoxy resin in any proportion.

3. The method for preparing a resin solid electrolyte with a directional pore structure as described in claim 1, characterized in that, In step (1), the magnetic response material is one or more of nano-iron oxide, nano-iron and nano-cobalt in any proportion.

4. The method for preparing the resin solid electrolyte with oriented channel structure as described in claim 1, characterized in that, In step (1), the mass of the added magnetic response material accounts for 0.5% to 10% of the total mass of the resin monomer and curing agent.

5. The method for preparing a resin solid electrolyte with a directional pore structure as described in claim 1, characterized in that, In step (2), the curing agent is one or a mixture of two of PACM and EK3402 in any proportion, and the mass ratio of epoxy resin monomer to curing agent is 1: (0.2~0.3).

6. The method for preparing a resin solid electrolyte with a directional pore structure as described in claim 1, characterized in that, In step (2), the mold material is one of polytetrafluoroethylene, aluminum alloy and copper alloy.

7. The method for preparing the resin solid electrolyte with oriented pore structure as described in claim 1, characterized in that, In step (4), the etching solution is one or a mixture of two of sulfuric acid and hydrochloric acid in any proportion, with an acid concentration range of 1 mol / L to 7 mol / L.

8. The method for preparing a resin solid electrolyte with a directional pore structure as described in claim 1, characterized in that, In step (5), the ion electrolyte is LB-266, LB-632 or LX-031, and the soaking time is not less than 10 hours.

9. A resin solid electrolyte with a directional pore structure prepared by the preparation method according to any one of claims 1 to 8.

10. The resin solid electrolyte with oriented channel structure as described in claim 9, characterized in that, The ionic conductivity of the resin solid electrolyte ranges from 0.1 mS / cm to 3.0 mS / cm, and the mechanical tensile strength under ASTM D638 standard testing ranges from 40 MPa to 85 MPa.

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