CN107069083A - A kind of solid polymer electrolyte membrane material that nanochannel is shifted with continuous ionic and preparation method thereof - Google Patents

Abstract

The invention relates to a solid polymer electrolyte membrane material with continuous ion transfer nano-channels, which is a membrane formed by the fusion and crosslinking of spherical micelles formed by the self-assembly of amphiphilic polymers. The preparation method is as follows: selecting a Co-solvent, configure a certain concentration of polycyclooctene grafted polyethylene glycol (PCOE-g-MPEG) comb copolymer solution; select a selective solvent, slowly add dropwise to the above-mentioned comb copolymer solution under stirring; The mixed solution is dialyzed; a certain amount of lithium salt is added to the dialyzed micellar solution, and the volatile solvent is concentrated to obtain flocculent stacked micelles; an oven heat treatment is used to obtain a solid polymer electrolyte membrane. The solid polymer electrolyte membrane obtained by the invention can form a continuous ion transfer channel when the MPEG content is low, and maintain high electrical conductivity and good mechanical properties.

Description

A solid polymer electrolyte membrane material with continuous ion-transfer nanochannels and its preparation method

technical field

The invention relates to a solid polymer electrolyte membrane material with continuous ion transfer nano-channels and a preparation method thereof, belonging to the field of preparation of lithium ion solid polymer electrolyte membrane materials.

Background technique

Lithium-ion batteries are widely used in various consumer electronics products due to their high energy density, fast charge and discharge, etc. The electrolyte used is mainly electrolyte containing lithium salt, which is easy to leak, flammable and explosive, etc. Security risks. Therefore, solid polymer electrolytes with excellent safety and stability have emerged as the times require, and have begun to receive extensive attention and research.

Among many solid polymer electrolytes, polymer electrolytes based on polyethylene glycol (PEO) and polyethylene glycol monomethyl ether (MPEG) are considered because of their relatively high electrochemical stability and ionic conductivity. It is the system with the most practical application potential. Initially, these copolymers were prepared into membranes by simple spin-coating or casting methods, and the results showed that the ion conductivity of the membrane was low due to the poor continuity of the ion-conducting region. For example, Kosonen, H. et al. (Macromolecules, 2002, 35, 27) used PS block P4VP (covalently linked with low molecular weight PEO) polymer solution to prepare the polymer electrolyte membrane with a conductivity of only 10 at room temperature ^{. 7} -10 ^-6 S/cm. Recent studies have shown that thermal annealing, solvent annealing and other treatments on the above-mentioned polymer membranes can induce the formation of an ordered two-phase continuous structure in the membrane, and the formation of this continuous channel can ensure that the electrolyte membrane maintains good mechanical strength while maintaining good ionic conductivity. For example, Schulze, MW et al. (Nano letters, 2014, 14, 1) reported a method based on a one-pot polymerization method to induce phase separation to form a two-phase continuous polymer electrolyte membrane, which obtained an ion conductivity exceeding 10 ^-3 at 80 °C s/cm. Villaluenga, I. et al. (Macromolecules, 2015, 48, 2) showed that the ionic conductivity of the polymer electrolyte membrane was greatly improved after the phase structure transition from layered to two-phase continuous was achieved by adding functionalized nanoparticles. However, from these examples, we can also see that this method of forming continuous channels by annealing is only suitable for polymer systems with high PEO/MPEG molecular weight or content, and the low-temperature crystallinity of PEO/MPEG limits its use conditions. It is a high temperature environment. Therefore, how to make the system with low PEO/MPEG molecular weight or content to form continuous ion conduction channels, and how to realize the low-temperature use value of solid polymer electrolytes will be the hotspots and difficulties in future research.

Contents of the invention

The technical problem to be solved by the present invention is to provide a solid polymer electrolyte membrane material with continuous ion transfer nano-channels and its preparation method in view of the shortcomings of the above-mentioned prior art. It has continuous ion transfer MPEG channels and realizes high conductivity at room temperature. rate and good mechanical properties.

The technical scheme that the present invention adopts for solving the above-mentioned problem is:

A solid polymer electrolyte membrane material with continuous ion transfer nanochannels, which is a membrane formed by the fusion and crosslinking of micelles formed by self-assembly of amphiphilic polymers; the micelles are spherical or ellipsoidal in shape, and the size The range is about 50nm-500nm

According to the above scheme, the amphiphilic polymer is polycyclooctene grafted polyethylene glycol monomethyl ether (PCOE-g-MPEG) comb copolymer, its structural formula is shown in formula 1, wherein the value of n The range is about 5-25, wherein the relative molecular weight of polyethylene glycol monomethyl ether is 350-750, and the content is 10-30 wt % (mass percentage).

According to the above scheme, the lithium salt is selected from lithium perchlorate, lithium hexafluorophosphate, lithium tetrafluoroborate, lithium bistrifluoromethanesulfonimide and the like. Wherein, the ratio of lithium ions in the lithium salt to ether oxygen atoms in the amphiphilic polymer ([Li]/[EO]) is between 1:4˜1:12.

The present invention also provides a method for preparing the above-mentioned solid polymer electrolyte membrane material with continuous ion transfer nanochannels, the steps of which are as follows:

(6) Select a co-solvent to prepare polycyclooctene grafted polyethylene glycol monomethyl ether (PCOE-g-MPEG) comb copolymer solution;

(7) Select a selective solvent, slowly drop the selective solvent into the comb copolymer solution obtained in step (1) under stirring, to obtain a mixed solution;

(8) Dialysis: dialyze the mixed solution obtained in step (2) to obtain a spherical micellar solution;

(9) concentration: adding lithium salt to the obtained spherical micelles solution, volatilizing the solvent, and concentrating to obtain flocculent stacking micelles;

(10) Crosslinking: thermal oxygen treatment of the obtained flocculent stacked micelles to obtain a solid polymer electrolyte membrane material with continuous ion transfer nanochannels.

According to the scheme, the co-solvent is polycyclooctene-grafted polyethylene glycol monomethyl ether (PCOE-g-MPEG) comb copolymer with good solubility in main chain (PCOE) and side chain (MPEG). solvent. Preferably, the co-solvent is selected from dichloromethane or chloroform or the like.

According to the above scheme, the concentration of the comb copolymer solution described in the step (1) is 0.1wt%～1wt%

According to the above scheme, the selective solvent is a good solvent for the side chain MPEG of polycyclooctene grafted polyethylene glycol monomethyl ether (PCOE-g-MPEG) comb copolymer, and for the main chain PCOE It is a poor solvent. Preferably, the selective solvent is selected from ethanol or methanol and the like.

According to the above scheme, the volume ratio of the selective solvent to the co-solvent is 3:1～1:3.

According to the above scheme, the conditions of the dialysis are: the molecular weight cut-off is less than or equal to 300KD, the time is 3-5 days, and ethanol or methanol is used as the dialysate.

According to the above scheme, the ratio ([Li]/[EO]) of the lithium ions in the lithium salt to the ether oxygen atoms in the comb copolymer is between 1:4˜1:12.

According to the above scheme, the thermal oxygen treatment temperature is 80°C to 100°C.

Compared with prior art, the beneficial effect of the present invention is:

First, the polymer solid polymer electrolyte membrane material obtained in the present invention has continuous ion transfer MPEG channels, and the ion conductivity at room temperature (25°C) is greater than 10 ^-3 s/cm, and at the same time realizes the continuous ionization of the polymer electrolyte membrane with low MPEG content. Conductive channel formation and high electrical conductivity at room temperature (i.e. low temperature use value), and good mechanical properties.

Second, the polycyclooctene grafted polyethylene glycol monomethyl ether (PCOE-g-MPEG) comb copolymer used in the present invention self-assembles into micelles to prepare polymer electrolyte membranes with continuous ion transfer channels, PCOE- During the dialysis process, the g-MPEG comb copolymer solution will form spherical micelles with MPEG hydrophilic branch chain as the shell and PCOE hydrophobic main chain as the core. After the micelles are concentrated and thermal oxygen treatment, a continuous ion conductor phase containing the MPEG shell is obtained. The two-phase continuous polymer electrolyte membrane with the PCOE core cross-linked phase is fundamentally different from the existing method of using solvent annealing or thermal annealing to induce the formation of a continuous phase region of the membrane, and provides a new idea for this field.

The 3rd, in the polycyclooctene graft polyethylene glycol monomethyl ether (PCOE-g-MPEG) comb copolymer used in the present invention, MPEG content is low, and contained MPEG relative molecular weight is low (350-750) , does not crystallize, realizes high conductivity at room temperature, and has good potential application value in the field of electronic equipment used at low temperature; moreover, the PCOE main chain of the comb polymer contains unsaturated carbon-carbon double bonds, and the obtained polymerization is obtained after thermal oxygen crosslinking The physical electrolyte membrane provides good mechanical strength and can be processed into various shapes according to needs.

Description of drawings

Fig. 1 is a schematic illustration of various implementation steps of the solid polymer electrolyte membrane material with continuous ion transfer nanochannels of the present invention.

Fig. 2 is the TEM photo of the micellar solution obtained after dialysis in Example 1.

FIG. 3 is an SEM photo of the solid polymer electrolyte membrane obtained after thermal oxygen crosslinking treatment in Example 1. FIG.

detailed description

In order to better understand the present invention, the content of the present invention is further illustrated below in conjunction with the examples, but the present invention is not limited to the following examples.

In the following examples, the polycyclooctene grafted polyethylene glycol monomethyl ether (PCOE-g-MPEG) comb copolymer has a structural formula shown in Formula 1, and its preparation method is not limited. The invention provides a preparation method as follows:

(1) Under ice-bath conditions, disperse 0.32mol of m-chloroperoxybenzoic acid (mCPBA) in 800mL of chloroform to obtain solution A; disperse 0.32mol of cyclooctadiene in 80mL of chloroform to obtain Solution B; slowly add solution A dropwise to solution B, and react at room temperature for 12 hours to obtain epoxycyclooctene;

(2) Under an argon atmosphere, disperse 0.889mol of epoxy cyclooctene in 80mL of tetrahydrofuran to obtain solution C; disperse 0.0889mol of lithium aluminum tetrahydride in 60mL of tetrahydrofuran to obtain solution D; slowly drop solution C Add it to solution D, add it dropwise for 0.5h under ice bath, then let it rise naturally to room temperature and react for 12h _; solution until no bubbles are generated in the system to obtain 5-hydroxyl-1-cyclooctene;

(3) Under the protection of argon, disperse 0.004mol of polyethylene glycol monomethyl ether (MPEG, the relative molecular mass is selected from the range of 350 to 750 as required) in 10mL of toluene to obtain solution E; 0.0042mol of 2,4-Toluene diisocyanate (TDI) was dispersed in 10mL of toluene to obtain solution F; solution E was added dropwise to solution F, reacted at 40°C for 24h, then heated to 90°C, and then slowly added dropwise 0.004mol 5-hydroxy-1-cyclooctene in 8mL of toluene solution was reacted for 24h under the protection of argon to obtain a macromonomer;

(4) Under argon atmosphere, dissolve in dichloromethane and add to A dry Schlenk bottle; in a small test tube, Grubbs' second-generation catalyst was dissolved in dichloromethane; after the above two solutions were frozen/vacuumized/thawed three times, the catalyst solution was quickly added dropwise to the monomer solution, React at room temperature to obtain the target product—polycyclooctene grafted with polyethylene glycol monomethyl ether (PCOE-g-MPEG) comb copolymer.

Above-mentioned gained polycyclooctene graft polyethylene glycol monomethyl ether (PCOE-g-MPEG) comb copolymer, its structural formula is as shown in formula 1, relative molecular mass is 5000-20000, the value of repeating unit number n The range is about 5-25, the relative molecular mass of polyethylene glycol monomethyl ether (MPEG) is 350-750, and the content is 10-30 wt%.

Example 1

A solid polymer electrolyte membrane material with continuous ion-transfer nanochannels, which is a comb copolymer (molecular weight of 5,000 to 20,000, wherein The MPEG content is 30wt%, and the relative molecular weight of MPEG is 350). The micelles formed by self-assembly are fused with lithium salt, and the film formed by cross-linking; wherein the micelles are spherical or ellipsoidal in shape, and the size range is about 50nm-500nm.

The above-mentioned preparation method of the solid polymer electrolyte membrane material with continuous ion transfer nanochannels, the steps are as follows:

(1) Accurately weigh 0.05g of PCOE-g-MPEG (the relative molecular mass of MPEG is 350, and the mass fraction is 30%) comb polymer is dissolved in 10g of dry co-solvent CH ₂ Cl ₂ to obtain a mass fraction of 5‰ The comb copolymer solution;

(2) Measure 7.5ml of selective solvent ethanol, add the above-mentioned comb copolymer solution dropwise under stirring at room temperature, the volume ratio of selective solvent to co-solvent is 1:1;

(3) transfer the solution obtained in step (2) into a dialysis bag with a molecular weight cut-off of 3500, dialyze in a large amount of ethanol for 3 to 5 days, change the dialysate once during the period, and obtain micellar emulsion after the dialysis;

(4) fully shake the obtained micellar emulsion, add 0.005g anhydrous lithium perchlorate therein, make [Li]/[EO] be 1:8, room temperature volatilize solvent, obtain white flocculent accumulation;

(5) Transfer the obtained flocculent accumulation into an oven and heat-treat at 80° C. for 12 hours to obtain a solid polymer electrolyte membrane with continuous ion transfer nanochannels.

As can be seen from Figure 2: the polycyclooctene grafted polyethylene glycol monomethyl ether (PCOE-g-MPEG) comb copolymer self-assembles into spherical micelles as an amphiphilic polymer; According to the hydrophilic and hydrophobic properties of the main and side chains of the polymer, it can be seen that the shell part of the spherical micelles is an MPEG chain, and the core part is a PCOE chain. Bonded cross-links provide mechanical strength

It can be seen from Figure 3 that the solid polymer electrolyte membrane obtained after thermal oxygen cross-linking of the micelles is the fusion between the comb-like copolymer spherical micelles, and the spherical micelles are cross-linked together to form a solid polymer electrolyte membrane.

The solid polymer electrolyte membrane with continuous ion transfer nanochannels obtained in this example is tested by an electrochemical workstation for its AC impedance, and is substituted into the conductivity calculation formula σ=L/R*S (wherein L is the film thickness, R is the resistance, and S is the film area), the electrical conductivity is 3.42*10- ⁴ s/cm, the tensile strength is 2.5MP, and the first discharge capacity at room temperature is 87mAh/g.

Example 2

A method for preparing a solid polymer electrolyte membrane material with continuous ion transfer nanochannels, the steps are as follows:

(1) Accurately weigh 0.05g of PCOE-g-MPEG (the relative molecular mass of MPEG is 350, and the mass fraction is 30%) comb polymer is dissolved in 10g of dry co-solvent CH ₂ Cl ₂ to obtain a mass fraction of 5‰ The solution;

(2) Measure 7.5ml of selective solvent ethanol, and add the above solution dropwise under stirring at room temperature, so that the final volume ratio of selective solvent to co-solvent is 1:1;

(3) Transfer the solution obtained in (2) into a dialysis bag with a molecular weight cut-off of 3500, and dialyze in a large amount of ethanol solution for 3 to 5 days, during which time the dialysate is replaced;

(4) After the dialysis is completed, fully shake the obtained micellar emulsion, add 0.010g of anhydrous lithium perchlorate to make [Li]/[EO] 1:4, and evaporate the solvent at room temperature to obtain a white flocculent accumulation;

(5) Transfer the obtained flocculent accumulation into an oven and heat-treat at 80° C. for 12 hours to obtain a solid polymer electrolyte membrane with continuous ion transfer nanochannels. The AC impedance was tested by EIS, and the conductivity calculation formula σ=L/R*S was substituted to obtain a conductivity of 8.75*10- ⁵ s/cm, a tensile strength of 2.2MP, and a room temperature initial discharge capacity of 65mAh/g.

Example 3

A method for preparing a solid polymer electrolyte membrane material with continuous ion transfer nanochannels, the steps are as follows:

(1) Accurately weigh 0.05g of PCOE-g-MPEG (the relative molecular mass of MPEG is 350, and the mass fraction is 30%) comb polymer is dissolved in 10g of dry co-solvent CH ₂ Cl ₂ to obtain a mass fraction of 5‰ The solution;

(2) Measure 7.5ml of selective solvent ethanol, and add the above solution dropwise under stirring at room temperature, so that the final volume ratio of selective solvent to co-solvent is 1:1;

(3) Transfer the solution obtained in (2) into a dialysis bag with a molecular weight cut-off of 3500, and dialyze in a large amount of ethanol solution for 3 to 5 days, during which time the dialysate is replaced;

(4) After the end of dialysis, fully shake the obtained micellar emulsion, add 0.003g of anhydrous lithium perchlorate to make [Li]/[EO] 1:12, and evaporate the solvent at room temperature to obtain white flocculent accumulations;

(5) Transfer the obtained flocculent accumulation into an oven and heat-treat at 80° C. for 12 hours to obtain a solid polymer electrolyte membrane with continuous ion transfer nanochannels. Using EIS to test its AC impedance, and substituting the conductivity calculation formula σ=L/R*S, the conductivity is 2.19*10- ⁵ s/cm, the tensile strength is 2.9MP, and the first discharge capacity at room temperature is 96mAh/g.

In embodiment 1,2,3, the MPEG chain length and content of polycyclooctene graft polyethylene glycol monomethyl ether (PCOE-g-MPEG) comb copolymer are all identical, change lithium salt content, the result shows that [ When Li]/[EO] is 1:8, the ionic conductivity of the obtained solid polymer electrolyte membrane is higher, which may be due to the highest utilization efficiency of lithium ions and ether oxygen atoms at this lithium salt content.

Example 4

A method for preparing a solid polymer electrolyte membrane material with continuous ion transfer nanochannels, the steps are as follows:

(1) Accurately weigh 0.05g of PCOE-g-MPEG (the relative molecular mass of MPEG is 350, and the mass fraction is 25%) comb polymer is dissolved in 10g of dry co-solvent CH ₂ Cl ₂ to obtain a mass fraction of 5‰ The solution;

(2) Measure 7.5ml of selective solvent ethanol, and add the above solution dropwise under stirring at room temperature, so that the final volume ratio of selective solvent to co-solvent is 1:1;

(3) Transfer the solution obtained in (2) into a dialysis bag with a molecular weight cut-off of 3500, and dialyze in a large amount of ethanol solution for 3 to 5 days, during which time the dialysate is replaced;

(4) After the dialysis is completed, fully shake the obtained micellar emulsion, add 0.004g of anhydrous lithium perchlorate, so that [Li]/[EO] is 1:8, evaporate the solvent at room temperature, and obtain a white flocculent accumulation;

(5) Transfer the obtained flocculent accumulation into an oven and heat-treat at 80° C. for 12 hours to obtain a solid polymer electrolyte membrane with continuous ion transfer nanochannels. The AC impedance was tested by EIS, and the conductivity calculation formula σ=L/R*S was substituted to obtain a conductivity of 2.69*10- ⁴ s/cm, a tensile strength of 3.2MP, and a room temperature initial discharge capacity of 58mAh/g.

Example 5

A method for preparing a solid polymer electrolyte membrane material with continuous ion transfer nanochannels, the steps are as follows:

(1) Accurately weigh 0.05g of PCOE-g-MPEG (MPEG relative molecular mass is 350, mass fraction is 20%) comb polymer is dissolved in 10g of dry co _- solvent _CH2Cl2 to obtain a mass fraction of 5‰ The solution;

(2) Measure 7.5ml of selective solvent ethanol, and add the above solution dropwise under stirring at room temperature, so that the final volume ratio of selective solvent to co-solvent is 1:1;

(3) Transfer the solution obtained in (2) into a dialysis bag with a molecular weight cut-off of 3500, and dialyze in a large amount of ethanol solution for 3 to 5 days, during which time the dialysate is replaced;

(4) After the dialysis is completed, fully shake the obtained micellar emulsion, add 0.003g of anhydrous lithium perchlorate, so that [Li]/[EO] is 1:8, evaporate the solvent at room temperature, and obtain a white flocculent accumulation;

(5) Transfer the obtained flocculent accumulation into an oven and heat-treat at 80° C. for 12 hours to obtain a solid polymer electrolyte membrane with continuous ion transfer nanochannels. Using EIS to test its AC impedance, and substituting the conductivity calculation formula σ=L/R*S, the conductivity is 2.38*10- ⁴ s/cm, the tensile strength is 2.8MP, and the first discharge capacity at room temperature is 75mAh/g.

In Examples 1, 4, and 5, the length of the MPEG side chain of the polycyclooctene-grafted polyethylene glycol monomethyl ether (PCOE-g-MPEG) comb copolymer and the lithium salt content in the solid polymer film are the same, and the side chain length is the same. The content of the chain MPEG (side chain branch density) gradually decreases, but the conductivity value does not change significantly. The reason may be that the MPEG chains in each embodiment have formed continuous MPEG ion transfer channels, and different mass fractions have no significant impact. .

Example 6

A method for preparing a solid polymer electrolyte membrane material with continuous ion transfer nanochannels, the steps are as follows:

(1) Accurately weigh 0.05g of PCOE-g-MPEG (MPEG relative molecular mass is 550, mass fraction is 50%) comb polymer is dissolved in 10g of dry co _- solvent _CH2Cl2 to obtain a mass fraction of 5‰ The solution;

(2) Measure 7.5ml of selective solvent ethanol, and add the above solution dropwise under stirring at room temperature, so that the final volume ratio of selective solvent to co-solvent is 1:1;

(3) Transfer the solution obtained in (2) into a dialysis bag with a molecular weight cut-off of 3500, and dialyze in a large amount of ethanol solution for 3 to 5 days, during which time the dialysate is replaced;

(4) After the dialysis is completed, fully shake the obtained micellar emulsion, add 0.008g of anhydrous lithium perchlorate, so that [Li]/[EO] is 1:8, evaporate the solvent at room temperature, and obtain a white flocculent accumulation;

(5) Transfer the obtained flocculent accumulation into an oven and heat-treat at 80° C. for 12 hours to obtain a solid polymer electrolyte membrane with continuous ion transfer nanochannels. The AC impedance was tested by EIS, and the conductivity calculation formula σ=L/R*S was substituted to obtain a conductivity of 8.32*10- ⁴ s/cm, a tensile strength of 1.6MP, and a room temperature initial discharge capacity of 92mAh/g.

Example 7

A method for preparing a solid polymer electrolyte membrane material with continuous ion transfer nanochannels, the steps are as follows:

(1) Accurately weigh 0.05g of PCOE-g-MPEG (the relative molecular mass of MPEG is 550, and the mass fraction is 40%) comb polymer is dissolved in 10g of dry co-solvent CH ₂ Cl ₂ to obtain a mass fraction of 5‰ The solution;

(2) Measure 7.5ml of selective solvent ethanol, and add the above solution dropwise under stirring at room temperature, so that the final volume ratio of selective solvent to co-solvent is 1:1;

(3) Transfer the solution obtained in (2) into a dialysis bag with a molecular weight cut-off of 3500, and dialyze in a large amount of ethanol solution for 3 to 5 days, during which time the dialysate is replaced;

(4) After the dialysis is completed, fully shake the obtained micellar emulsion, add 0.006g of anhydrous lithium perchlorate to make [Li]/[EO] 1:8, and evaporate the solvent at room temperature to obtain a white flocculent accumulation;

(5) Transfer the obtained flocculent accumulation into an oven and heat-treat at 80° C. for 12 hours to obtain a solid polymer electrolyte membrane with continuous ion transfer nanochannels. The AC impedance was tested by EIS, and the conductivity calculation formula σ=L/R*S was substituted to obtain a conductivity of 3.46*10- ⁴ s/cm, a tensile strength of 1.3MP, and a room temperature initial discharge capacity of 66mAh/g.

Example 8

A method for preparing a solid polymer electrolyte membrane material with continuous ion transfer nanochannels, the steps are as follows:

(1) Accurately weigh 0.05g of PCOE-g-MPEG (the relative molecular mass of MPEG is 750, and the mass fraction is 60%) comb polymer is dissolved in 10g of dry co-solvent CH ₂ Cl ₂ to obtain a mass fraction of 5‰ The solution;

(2) Measure 7.5ml of selective solvent ethanol, and add the above solution dropwise under stirring at room temperature, so that the final volume ratio of selective solvent to co-solvent is 1:1;

(3) Transfer the solution obtained in (2) into a dialysis bag with a molecular weight cut-off of 3500, and dialyze in a large amount of ethanol solution for 3 to 5 days, during which time the dialysate is replaced;

(4) After the end of dialysis, fully shake the obtained micellar emulsion, add 0.009g of anhydrous lithium perchlorate to make [Li]/[EO] 1:8, and evaporate the solvent at room temperature to obtain white flocculent accumulations;

(5) Transfer the obtained flocculent accumulation into an oven and heat-treat at 80° C. for 12 hours to obtain a solid polymer electrolyte membrane with continuous ion transfer nanochannels. Using EIS to test its AC impedance, and substituting the conductivity calculation formula σ=L/R*S, the conductivity is 1.62*10- ⁴ s/cm, the tensile strength is 0.9MP, and the first discharge capacity at room temperature is 72mAh/g.

Example 9

A method for preparing a solid polymer electrolyte membrane material with continuous ion transfer nanochannels, the steps are as follows:

(1) Accurately weigh 0.05g of PCOE-g-MPEG (the relative molecular mass of MPEG is 750, the mass fraction is 50%) comb polymer is dissolved in 10g of dry co-solvent CH ₂ Cl ₂ to obtain a mass fraction of 5‰ The solution;

(2) Measure 7.5ml of selective solvent ethanol, and add the above solution dropwise under stirring at room temperature, so that the final volume ratio of selective solvent to co-solvent is 1:1;

(3) Transfer the solution obtained in (2) into a dialysis bag with a molecular weight cut-off of 3500, and dialyze in a large amount of ethanol solution for 3 to 5 days, during which time the dialysate is replaced;

(4) After the dialysis is completed, fully shake the obtained micellar emulsion, add 0.008g of anhydrous lithium perchlorate, so that [Li]/[EO] is 1:8, evaporate the solvent at room temperature, and obtain a white flocculent accumulation;

(5) Transfer the obtained flocculent accumulation into an oven and heat-treat at 80° C. for 12 hours to obtain a solid polymer electrolyte membrane with continuous ion transfer nanochannels. The AC impedance was measured by EIS, and the conductivity calculation formula σ=L/R*S was substituted to obtain a conductivity of 1.35*10- ⁴ s/cm, a tensile strength of 1.8MP, and a room temperature initial discharge capacity of 54mAh/g.

In summary, the ionic conductivity of the solid polymer electrolyte membrane of the present invention can reach 10- ³ s/cm, the tensile strength is about 1-3MP, and the initial discharge capacity at room temperature is about 50mAh/g-100mAh/g.

The above is only a preferred embodiment of the present invention, it should be pointed out that for those of ordinary skill in the art, without departing from the creative concept of the present invention, some improvements and changes can also be made, and these all belong to the present invention scope of protection.

Claims (10)

1. A solid polymer electrolyte membrane material with continuous ion transfer nanochannels, characterized in that it is a film formed by the fusion and crosslinking of micelles formed by self-assembly of amphiphilic polymers; wherein the micelles are spherical in shape Or ellipsoidal, with a size range of about 50-500 nm. 2. A kind of solid polymer electrolyte membrane material with continuous ion transfer nanochannel according to claim 1, characterized in that said amphiphilic polymer is polycyclooctene grafted polyethylene glycol monomethyl ether comb Shape copolymer, its structural formula is as shown in formula 1, Wherein, the value range of n is between 5-25, the relative molecular mass of polyethylene glycol monomethyl ether is 350-750, and the content is 10-30 wt%. 3. A kind of solid polymer electrolyte membrane material with continuous ion transfer nanochannel according to claim 1, characterized in that said lithium salt is lithium perchlorate, lithium hexafluorophosphate, lithium tetrafluoroborate or bistrifluoromethyl One or more of lithium sulfonylimides. 4. a kind of solid polymer electrolyte membrane material with continuous ion transfer nanochannel according to claim 1, is characterized in that the ratio of the lithium ion in the lithium salt and the ether oxygen atom in the amphiphilic polymer ( [Li]/[EO]) between 1:4 and 1:12. 5. A method for preparing a solid polymer electrolyte membrane material with continuous ion transfer nanochannels, characterized in that the main steps are as follows: (1) select a kind of co-solvent, prepare polycyclooctene graft polyethylene glycol monomethyl ether comb copolymer solution; (2) Select a selective solvent, and drop the selective solvent into the comb copolymer solution obtained in step (1) under stirring to obtain a mixed solution; (3) Dialysis: dialyze the mixed solution obtained in step (2) to obtain a spherical micellar solution; (4) concentration: adding lithium salt to the obtained spherical micelles solution, volatilizing the solvent, and concentrating to obtain flocculent stacking micelles; (5) Crosslinking: thermal oxygen treatment of the obtained flocculent stacked micelles to obtain a solid polymer electrolyte membrane material with continuous ion transfer nanochannels. 6. the preparation method of a kind of solid polymer electrolyte membrane material with continuous ion transfer nanochannel according to claim 5, it is characterized in that described co-solvent is polycyclooctene graft polyethylene glycol monomethyl ether comb The main chain and the side chain of the shape copolymer are all good solvents of solubility; The selective solvent is the good solvent of the side chain of polycyclooctene grafted polyethylene glycol monomethyl ether comb copolymer, and the poor solvent of the main chain Solvent; the volume ratio of the selective solvent to the co-solvent is 3:1-1:3. 7. a kind of preparation method with the solid polymer electrolyte membrane material of continuous ion transfer nanochannel according to claim 5, it is characterized in that the concentration of the comb copolymer solution in the described step (1) is 0.1wt %～1wt%. 8. A method for preparing a solid polymer electrolyte membrane material with continuous ion transfer nanochannels according to claim 5, characterized in that the conditions of the dialysis are: the molecular weight cut-off is less than or equal to 300KD, and the time is 3 to 5 days. Use ethanol or methanol as the dialysate. 9. The solid polymer electrolyte membrane material with continuous ion transfer nanochannel obtained by the method of claims 5-8. 10. The solid polymer electrolyte membrane material with continuous ion transfer nanochannels according to claim 9, characterized in that its ion conductivity at room temperature is greater than 10 ^-3 s/cm.