CN114188602B - Boron-containing solid polymer electrolyte, preparation method thereof and lithium battery - Google Patents

Boron-containing solid polymer electrolyte, preparation method thereof and lithium battery Download PDF

Info

Publication number
CN114188602B
CN114188602B CN202111253975.1A CN202111253975A CN114188602B CN 114188602 B CN114188602 B CN 114188602B CN 202111253975 A CN202111253975 A CN 202111253975A CN 114188602 B CN114188602 B CN 114188602B
Authority
CN
China
Prior art keywords
boron
polymer electrolyte
solid polymer
containing solid
lithium
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
CN202111253975.1A
Other languages
Chinese (zh)
Other versions
CN114188602A (en
Inventor
谢海明
李雅男
丛丽娜
刘玉龙
孙立群
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Jilin Dongchi New Energy Technology Co ltd
Original Assignee
Jilin Dongchi New Energy Technology Co ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Jilin Dongchi New Energy Technology Co ltd filed Critical Jilin Dongchi New Energy Technology Co ltd
Priority to CN202111253975.1A priority Critical patent/CN114188602B/en
Publication of CN114188602A publication Critical patent/CN114188602A/en
Application granted granted Critical
Publication of CN114188602B publication Critical patent/CN114188602B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/056—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes
    • H01M10/0564—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes the electrolyte being constituted of organic materials only
    • H01M10/0565—Polymeric materials, e.g. gel-type or solid-type
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/052—Li-accumulators
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/052—Li-accumulators
    • H01M10/0525—Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/10—Energy storage using batteries

Abstract

The invention provides a boron-containing solid polymer electrolyte, a preparation method thereof and a lithium battery, belonging to the technical field of lithium batteries and comprising the following steps: and mixing the lithium salt with polyethylene oxide, a boron-containing crosslinking agent and a photoinitiator, and carrying out hot pressing and light irradiation to obtain the boron-containing solid polymer electrolyte. According to the invention, the boron group is introduced, so that the transference number of lithium ions is increased, the crystallinity of polyethylene oxide is reduced, the transmission of lithium ions is accelerated, the room-temperature conductivity of an electrolyte is improved, and the electrochemical performance of the battery is improved. The results of the examples show that the room temperature ionic conductivity of the boron-containing solid polymer electrolyte prepared by the present invention reaches 2.74 x 10 ‑4 S/cm, the transference number of lithium ions reaches 0.81, the electrochemical window reaches 5.35V, and the lithium battery containing the boron-containing solid polymer electrolyte has higher specific capacity and rate capability.

Description

Boron-containing solid polymer electrolyte, preparation method thereof and lithium battery
Technical Field
The invention relates to the technical field of lithium ion batteries, in particular to a boron-containing solid polymer electrolyte, a preparation method thereof and a lithium battery.
Background
With the continuous development of the emerging field, the demand on the lithium ion battery with high energy density is more and more, and in order to overcome the potential safety hazards of easy leakage, easy combustion and the like of the liquid electrolyte, the solid electrolyte is imperative to replace the liquid electrolyte.
The polymer electrolyte has the excellent characteristics of high temperature resistance, long service life and the like, can inhibit the growth of lithium dendrites, and solves a series of problems caused by the lithium dendrites. Ether oxygen in the polyoxyethylene chain segment can interact with lithium ions to dissolve various lithium salts, so that the lithium salts become common polymers of the current polymer electrolytes, but the lithium ion migration number of the polyoxyethylene-based polymer electrolytes is low and is basically about 0.2, so that the application of the lithium salts is limited.
Therefore, how to increase the transference number of lithium ions of the polymer electrolyte and further improve the performance of the lithium battery becomes a difficult problem in the prior art.
Disclosure of Invention
The invention aims to provide a boron-containing solid polymer electrolyte, a preparation method thereof and a lithium battery. The boron-containing solid polymer electrolyte prepared by the preparation method provided by the invention has excellent lithium ion transference number; the lithium battery containing the boron-containing solid polymer electrolyte has excellent specific capacity and rate capability.
In order to achieve the above object, the present invention provides the following technical solutions:
the invention provides a preparation method of a boron-containing solid polymer electrolyte, which comprises the following steps:
(1) Mixing lithium salt with polyethylene oxide, a boron-containing crosslinking agent and a photoinitiator to obtain a precursor solution;
(2) And (2) sequentially carrying out hot pressing and light irradiation on the precursor solution obtained in the step (1) to obtain the boron-containing solid polymer electrolyte.
Preferably, the ratio of the lithium salt to the amount of the substance of the ethylene oxide monomer for preparing the polyethylene oxide in the step (1) is 1 (15-30).
Preferably, the mass ratio of the boron-containing crosslinking agent to the polyethylene oxide in the step (1) is (1-6): 3.
Preferably, the ratio of the mass of the photoinitiator in the step (1) to the total mass of the polyethylene oxide and the boron-containing crosslinking agent is (1-10): 100.
Preferably, the hot pressing temperature in the step (2) is 30-100 ℃, and the hot pressing pressure is 1-2 MPa.
Preferably, the light source of the light irradiation in the step (2) is ultraviolet light.
Preferably, the wavelength of the ultraviolet light is 200 to 380nm.
Preferably, the time of light irradiation in the step (2) is 1-30 min, and the light intensity of light irradiation is 50-200 mW/cm 2 。
The invention provides the boron-containing solid polymer electrolyte prepared by the preparation method in the technical scheme.
The invention also provides a lithium battery, and the electrolyte of the lithium battery is the boron-containing solid polymer electrolyte prepared by the preparation method of the technical scheme or the boron-containing solid polymer electrolyte of the technical scheme.
The invention provides a preparation method of a boron-containing solid polymer electrolyte, which comprises the following steps: mixing lithium salt with polyethylene oxide, a boron-containing crosslinking agent and a photoinitiator to obtain a precursor solution; and sequentially carrying out hot pressing and light irradiation on the obtained precursor solution to obtain the boron-containing solid polymer electrolyte. According to the invention, boron groups are introduced by using a boron-containing crosslinking agent, anions of lithium salt are fixed through the electron interaction of boron with an empty p orbit, the transference number of lithium ions is increased, the Li + concentration gradient from an electrolyte to the surface of a lithium metal negative electrode is reduced, the electric field of a lithium metal electrode is reduced, and uniform lithium deposition is formed; in addition, the cross-linking reaction can form electrolyte with a space network structure, reduce the crystallinity of the polyethylene oxide, increase the amorphous area of the polyethylene oxide, accelerate the transmission of lithium ions and improve the room-temperature conductivity of the electrolyte, thereby improving the rate capability and the cycle performance of the battery. The results of the examples show that the room temperature ionic conductivity of the boron-containing solid polymer electrolyte prepared by the present invention reaches 2.74 x 10 -4 S/cm, the transference number of lithium ions can reach 0.81, the electrochemical window can reach 5.35V, the impedance of the contact surface of the lithium ion battery with a lithium sheet is small, the interface contact stability is good, and the lithium battery containing the boron-containing solid polymer electrolyte has high specific capacity and rate capability.
Drawings
FIG. 1 is a macroscopic view of a boron-containing solid polymer electrolyte prepared in example 1 of the present invention;
FIG. 2 is an SEM image of a boron-containing solid polymer electrolyte prepared in example 1 of the present invention;
FIG. 3 is a diagram showing the electrochemical window of a boron-containing solid polymer electrolyte prepared in example 1 of the present invention;
FIG. 4 is an I-t curve and impedance before and after testing of a Li// Li symmetric battery containing a boron-containing solid polymer electrolyte prepared in example 1 of the present invention;
FIG. 5 is a constant current charge-discharge voltage polarization curve of a Li// Li symmetric cell of boron-containing solid polymer electrolyte prepared in example 1 of the present invention;
FIG. 6 is a graph showing the impedance of boron-containing solid polymer electrolytes prepared in examples 1 and 3 to 7 according to the present invention;
fig. 7 is a rate cycle diagram of a button cell assembled in example 2 of the present invention.
Detailed Description
The invention provides a preparation method of a boron-containing solid polymer electrolyte, which comprises the following steps:
(1) Mixing lithium salt with polyethylene oxide, a boron-containing crosslinking agent and a photoinitiator to obtain a precursor solution;
(2) And (2) sequentially carrying out hot pressing and light irradiation on the precursor solution obtained in the step (1) to obtain the boron-containing solid polymer electrolyte.
In the present invention, the sources of the components are not particularly limited, unless otherwise specified, and commercially available products known to those skilled in the art may be used.
According to the invention, lithium salt is mixed with polyethylene oxide, a boron-containing crosslinking agent and a photoinitiator to obtain a precursor solution.
In the present invention, the average molecular weight of the polyethylene oxide is preferably 10000 to 1000000g/mol, more preferably 50000 to 500000g/mol, and most preferably 100000 to 300000g/mol. In the present invention, the polyethylene oxide serves as a host material of the solid polymer electrolyte. The invention limits the average molecular weight of the polyethylene oxide within the range, can enable the polyethylene oxide to have more ether oxygen groups, improves the lithium-conducting function and enables the electrolyte to have better mechanical property.
In the present invention, the lithium salt preferably includes one or more of lithium hexafluorophosphate, lithium perchlorate, lithium bistrifluoromethanesulfonylimide, lithium diglycolate borate and lithium difluorooxalato borate. In the present invention, the ratio of the amount of the lithium salt to the amount of the substance of the ethylene oxide monomer for preparing polyethylene oxide is preferably 1 (15 to 30), more preferably 1 (18 to 28), and most preferably 1 (20 to 25). The invention limits the quantity ratio of the lithium salt to the ethylene oxide monomer for preparing the polyethylene oxide in the range, can improve the content of the lithium salt in the electrolyte, further improve the performance of the electrolyte and avoid the agglomeration of the lithium salt.
In the present invention, the boron-containing crosslinking agent preferably includes a boron-containing rigid crosslinking agent and/or a boron-containing flexible crosslinking agent, and more preferably includes a boron-containing rigid crosslinking agent and a boron-containing flexible crosslinking agent.
In the present invention, the boron-containing rigid crosslinking agent preferably includes one or more compounds represented by formula 1, formula 2 and formula 3.
Figure BDA0003323403920000041
In the formulae 1, 2 and 3, n is independently preferably an integer of 1 to 50, more preferably an integer of 5 to 45, even more preferably an integer of 10 to 40, and most preferably an integer of 20 to 30.
In the present invention, the boron-containing flexible crosslinking agent preferably includes one or more of the compounds represented by formula 4.
Figure BDA0003323403920000042
In the above formula 4, m is preferably an integer of 1 to 50, more preferably an integer of 5 to 45, even more preferably an integer of 10 to 40, and most preferably an integer of 20 to 30.
In the present invention, the mass ratio of the boron-containing rigid crosslinking agent to the boron-containing flexible crosslinking agent is preferably (0 to 1): (1-2), more preferably (0.5-1): (1-2), most preferably 1. The invention limits the mass ratio of the boron-containing rigid cross-linking agent to the boron-containing flexible cross-linking agent within the range, can adjust the structure of the electrolyte and improves the mechanical property of the electrolyte.
In the present invention, the mass ratio of the boron-containing crosslinking agent to the polyethylene oxide is preferably (1 to 6): 3, more preferably (2 to 5): 3, and most preferably (3 to 4): 3. The invention limits the mass ratio of the boron-containing cross-linking agent to the polyethylene oxide within the range, can adjust the content of boron groups, fixes the anions of lithium salt through the electron interaction of boron with an air p orbit, improves the transference number of lithium ions, reduces the concentration gradient of Li < + > from an electrolyte to the surface of a lithium metal negative electrode, reduces the electric field of the lithium metal electrode, and forms uniform lithium deposition; meanwhile, the electrolyte structure can be adjusted, the crystallinity of the polyethylene oxide is reduced, the amorphous area of the polyethylene oxide is increased, the transmission of lithium ions is accelerated, the room-temperature conductivity of the electrolyte is further improved, and the rate capability and the cycle performance of the battery are further improved.
In the present invention, the photoinitiator preferably includes one or more of 2-hydroxy-2-methyl-1-phenyl-1-propanone, 4-methylbenzophenone, α -hydroxyisobutyrophenone and 1-hydroxycyclohexylphenylketone. In the present invention, the ratio of the mass of the photoinitiator to the total mass of the polyethylene oxide and the boron-containing crosslinking agent is preferably (1 to 10): 100, more preferably (2 to 9): 100, even more preferably (3 to 8): 100, and most preferably (5 to 6): 100. The invention limits the ratio of the mass of the photoinitiator to the total mass of the polyethylene oxide and the boron-containing crosslinking agent in the range, can enable the polyethylene oxide and the boron-containing crosslinking agent to better generate crosslinking reaction, and further improves the performance of the product.
In the present invention, the mixing of the lithium salt with the polyethylene oxide, the boron-containing crosslinking agent and the photoinitiator is preferably performed by mixing the lithium salt with the polyethylene oxide and the boron-containing crosslinking agent and then adding the photoinitiator. The photoinitiator is added finally, so that the phenomenon that the photoinitiator is contacted with polyethylene oxide and a boron-containing crosslinking agent for a long time and spontaneously generates crosslinking reaction to be solidified, and the photoinitiator cannot be melted in the hot pressing process, so that the thickness of the electrolyte is not uniform can be avoided.
In the present invention, the mixing of the lithium salt with the polyethylene oxide and the boron-containing crosslinking agent is preferably performed under stirring conditions; the stirring is preferably mechanical stirring; the rotating speed of the stirring is preferably 100-600 rpm; the stirring time is preferably 5 to 12 hours, and more preferably 7 to 10 hours; the stirring temperature is preferably 20 to 30 ℃. In the invention, the rotation speed of stirring after adding the photoinitiator is preferably 300-600 rpm; the stirring time is preferably 1-2 h; the stirring temperature is preferably 20 to 80 ℃, more preferably 50 to 70 ℃. The invention limits the stirring speed, temperature and time within the above range, and can make the components mixed more uniformly.
After the precursor solution is obtained, the invention carries out hot pressing and light irradiation on the precursor solution in sequence to obtain the boron-containing solid polymer electrolyte.
According to the invention, the precursor solution is preferably poured on the substrate, and then hot pressing and light irradiation are sequentially carried out, so that the boron-containing solid polymer electrolyte is obtained.
In the present invention, the substrate is preferably a polytetrafluoroethylene plate, a glass plate, or an aluminum foil, and more preferably a polytetrafluoroethylene plate. The size of the substrate is not specially limited, and the substrate can be selected according to actual needs.
The pouring amount of the precursor solution is not particularly limited, and the pouring amount is selected according to the thickness of the required electrolyte.
In the invention, the substrate after the precursor solution is poured is preferably heated and then hot-pressed.
In the present invention, the heating temperature is preferably 30 to 100 ℃, more preferably 50 to 80 ℃; the heating time is preferably 10 to 20min. In the present invention, the heating can promote the fluidity of the precursor solution.
After the heating is completed, the invention preferably covers the heated precursor solution with a polyethylene film. In the invention, the polyethylene film can enable the crosslinking reaction to be carried out under the oxygen-free condition, thereby further improving the performance of the electrolyte.
In the invention, the temperature of the hot pressing is preferably 30-100 ℃, and more preferably 50-80 ℃; the pressure of the hot pressing is preferably 1 to 2MPa, and more preferably 1.3 to 1.6MPa; the time for the hot pressing is preferably 1 to 3min, more preferably 2min. The present invention limits the temperature and pressure of the hot pressing to the above ranges, and can make the thickness of the polymer electrolyte more uniform.
In the present invention, the light source of the light irradiation is preferably ultraviolet light; the wavelength of the ultraviolet light is preferably 200-380 nm, and more preferably 365nm; said light irradiationThe time of (a) is preferably 1 to 30min, more preferably 5 to 25min, most preferably 10 to 20min; the light intensity of the light irradiation is preferably 50-200 mW/cm 2 More preferably 100 to 150mW/cm 2 . In the present invention, during the light irradiation, the polyethylene oxide and the boron-containing crosslinking agent undergo a radical crosslinking reaction under the action of the photoinitiator. The invention limits the light source, wavelength, time and light intensity of light irradiation in the above range, can make the cross-linking reaction more fully proceed, and further improves the product performance.
After the light irradiation is finished, the invention preferably removes the polyethylene film to obtain the boron-containing solid polymer electrolyte.
According to the invention, a boron-containing crosslinking agent is adopted to introduce boron groups, and anions of lithium salt are fixed through the electronic interaction of boron with an empty p orbit, so that the transference number of lithium ions is increased, the Li + concentration gradient from electrolyte to the surface of a lithium metal negative electrode is reduced, the electric field of a lithium metal electrode is reduced, and uniform lithium deposition is formed; in addition, the cross-linking reaction can form electrolyte with a space network structure, reduce the crystallinity of the polyethylene oxide, increase the amorphous area of the polyethylene oxide, accelerate the transmission of lithium ions, improve the room-temperature conductivity of the electrolyte, control the process parameters of the dosage, the reaction time, the temperature and the like of each component, and further improve the performance of the product.
The invention provides the boron-containing solid polymer electrolyte prepared by the preparation method in the technical scheme.
The boron-containing solid polymer electrolyte provided by the invention has excellent lithium ion transference number, room-temperature ionic conductivity and wider electrochemical window.
In the present invention, the thickness of the boron-containing solid polymer electrolyte is preferably 50 to 400. Mu.m, more preferably 100 to 280. Mu.m.
The invention also provides a lithium battery, and the electrolyte of the lithium battery is the boron-containing solid polymer electrolyte prepared by the preparation method of the technical scheme or the boron-containing solid polymer electrolyte of the technical scheme.
The composition of the positive electrode and the negative electrode of the lithium battery is not particularly limited in the invention, and the positive electrode material and the negative electrode material of the lithium battery well known to those skilled in the art can be adopted.
The preparation method of the lithium battery is not particularly limited, and the technical scheme for preparing the lithium battery, which is well known by the technical personnel in the field, is adopted.
The lithium battery provided by the invention has excellent rate capability and higher specific capacity.
The technical solution of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. It is to be understood that the described embodiments are merely exemplary of the invention, and not restrictive of the full scope of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Example 1
(1) Mixing 1.125g of polyethylene oxide with the average molecular weight of 300000g/mol, 0.125g of a compound shown in formula 3 (n is 6), 1g of 2- [2- (2-methoxyethoxy) ethoxy ] ethanol boric acid triester (a compound shown in formula 4, m is 3) (the mass ratio of a boron-containing crosslinking agent to polyethylene oxide is 3);
(2) Casting 0.5g of precursor solution on a polytetrafluoroethylene flat plate, heating at 70 ℃ for 15min, covering the polytetrafluoroethylene flat plate with a polyethylene film, carrying out hot pressing on the polytetrafluoroethylene flat plate covered with the polyethylene film at 1.5MPa for 2min, and irradiating under ultraviolet light for 8min, wherein the wavelength of the ultraviolet light is 365nm, and the intensity of the ultraviolet light is 150mW/cm 2 (ii) a And removing the polyethylene film after the light irradiation is finished to obtain the boron-containing solid polymer electrolyte with the thickness of 200 mu m.
A photograph of the boron-containing solid polymer electrolyte prepared in example 1 is shown in fig. 1.
Fig. 2 is an SEM image of the boron-containing solid polymer electrolyte prepared in example 1, and it can be seen from fig. 2 that the boron-containing solid polymer electrolyte prepared in example 1 exhibits regular network wrinkles, indicating that the resultant network solid polymer electrolyte is obtained.
The electrochemical window of the boron-containing solid polymer electrolyte prepared in example 1 was tested, and the results are shown in fig. 3, and it can be seen from fig. 3 that the oxidation potential of the boron-containing solid polymer electrolyte prepared in example 1 was raised to 5.35V.
The I-t curve of the Li// Li symmetric battery prepared in example 1 and impedance maps before and after the test were tested, and the results are shown in fig. 4, and it can be seen from fig. 4 that the transference number of lithium ions of the boron-containing solid polymer electrolyte prepared in example 1 at room temperature was as high as 0.81.
The Li// Li symmetric cell prepared in example 1 was tested for constant current charge and discharge voltage polarization curve of the boron-containing solid polymer electrolyte, and the result is shown in fig. 5, from which it can be seen that the polarization voltage curve of the cell was at a small current density (0.1 mAcm cm) -1 ) The lower part is relatively stable, and the overpotential is less than 0.2V.
The impedance diagram of the boron-containing solid polymer electrolyte prepared in example 1 was tested, and the results are shown in FIG. 6, and it can be seen from FIG. 6 that the boron-containing solid polymer electrolyte prepared in example 1 has a conductivity of 2.74X 10 at room temperature -4 S/cm。
Example 2
A button cell was assembled using the boron-containing solid polymer electrolyte prepared in example 1 as an electrolyte, the positive active material was lithium iron phosphate, the current collector was aluminum foil, the conductive agent was acetylene black, and the binder was polytetrafluoroethylene; the negative electrode is metallic lithium. The obtained button cell was subjected to rate cycling test, and the result is shown in fig. 7, and it can be seen from fig. 7 that the specific capacity of lithium iron phosphate at room temperature at 0.1C rate was 155mAh/g; the specific capacity of the lithium iron phosphate under the multiplying power of 0.2C is 149mAh/g; the specific capacity of the lithium iron phosphate under the multiplying power of 0.5C is 137mAh/g; the specific capacity of the lithium iron phosphate under the 1C multiplying power is 129mAh/g, and the specific capacity of the lithium iron phosphate can still reach 144mAh/g when the lithium iron phosphate returns to the 0.1C multiplying power, so that the obtained button cell has excellent multiplying power performance.
Example 3
(1) Mixing 1g of polyethylene oxide with the average molecular weight of 300000g/mol, 1g of 2- [2- (2-methoxyethoxy) ethoxy ] ethanol boric acid triester (compound of formula 4, m is 3) (the mass ratio of the boron-containing crosslinking agent to the polyethylene oxide is 3);
(2) Casting 0.5g of the precursor solution on a polytetrafluoroethylene flat plate, heating at 70 ℃ for 15min, covering the cast polytetrafluoroethylene flat plate with a polyethylene film, thermally pressing the polytetrafluoroethylene flat plate covered with the polyethylene film at 1.5MPa for 2min, and irradiating under ultraviolet light for 8min, wherein the wavelength of the ultraviolet light is 365nm, and the intensity of the ultraviolet light is 150mW/cm 2 (ii) a And removing the polyethylene film after the light irradiation is finished to obtain the boron-containing solid polymer electrolyte film with the thickness of 200 mu m.
The room-temperature conductivity of the boron-containing solid polymer electrolyte prepared in example 3 was 2.23X 10 -4 S/cm, the transference number of lithium ions is 0.56.
Example 4
(1) Mixing 1.1g of polyethylene oxide with the average molecular weight of 300000g/mol, 0.1g of a compound shown in a formula 3 (n is 6), 1g of 2- [2- (2-methoxyethoxy) ethoxy ] ethanol boric acid triester (a compound shown in a formula 4, m is 3) (the mass ratio of a boron-containing crosslinking agent to polyethylene oxide is 3);
(2) Casting 0.5g of the precursor solution on a polytetrafluoroethylene flat plate, heating at 70 ℃ for 15min, covering the polytetrafluoroethylene flat plate with a polyethylene film, carrying out hot pressing on the polytetrafluoroethylene flat plate covered with the polyethylene film at 1.5MPa for 2min, and irradiating under ultraviolet light for 8min, wherein the wavelength of the ultraviolet light is 365nm, and the intensity of the ultraviolet light is 150mW/cm 2 (ii) a And removing the polyethylene film after the light irradiation is finished to obtain the boron-containing solid polymer electrolyte film with the thickness of 200 mu m.
The room-temperature conductivity of the boron-containing solid polymer electrolyte prepared in example 4 was 1.05X 10 -4 S/cm, and the transference number of lithium ions is 0.63.
Example 5
(1) Mixing 1.25g of polyethylene oxide with an average molecular weight of 300000g/mol, 0.25g of a compound represented by formula 3 (n is 6), 1g of 2- [2- (2-methoxyethoxy) ethoxy ] ethanolic acid triester borate (compound of formula 4, m is 3) (mass ratio of boron-containing crosslinking agent to polyethylene oxide is 3) and 0.7275g of lithium bistrifluoromethanesulfonylimide (the ratio of the amount of lithium salt to the amount of ethylene oxide monomer used for the preparation of polyethylene oxide is 1: 20), stirring at 25 ℃ for 5 hours at a speed of 500r/min, then adding 0.09683g of 4-methylbenzophenone (the ratio of the mass of 4-methylbenzophenone to the total mass of polyethylene oxide and boron-containing crosslinking agent is 4: 100), mixing, and stirring at 30 ℃ for 1 hour at a speed of 400r/min to obtain a precursor solution;
(2) Casting 0.5g of the precursor solution on a polytetrafluoroethylene flat plate, heating at 70 ℃ for 15min, covering the polytetrafluoroethylene flat plate with a polyethylene film, carrying out hot pressing on the polytetrafluoroethylene flat plate covered with the polyethylene film at 1.5MPa for 2min, and irradiating under ultraviolet light for 8min, wherein the wavelength of the ultraviolet light is 365nm, and the intensity of the ultraviolet light is 150mW/cm 2 (ii) a And removing the polyethylene film after the light irradiation is finished to obtain the boron-containing solid polymer electrolyte film with the thickness of 200 mu m.
The room-temperature conductivity of the boron-containing solid polymer electrolyte prepared in example 5 was 1.38X 10 -4 S/cm, the transference number of lithium ions was 0.71.
Example 6
(1) Mixing 1.125g of polyethylene oxide with the average molecular weight of 300000g/mol, 0.125g of a compound shown in formula 1 (n is 6), 1g of 2- [2- (2-methoxyethoxy) ethoxy ] ethanol boric acid triester (a compound shown in formula 4, m is 3) (the mass ratio of a boron-containing crosslinking agent to polyethylene oxide is 3);
(2) Casting 0.5g of the precursor solution on a polytetrafluoroethylene flat plate, heating at 70 ℃ for 15min, covering the polytetrafluoroethylene flat plate with a polyethylene film, carrying out hot pressing on the polytetrafluoroethylene flat plate covered with the polyethylene film at 1.5MPa for 2min, and irradiating under ultraviolet light for 8min, wherein the wavelength of the ultraviolet light is 365nm, and the intensity of the ultraviolet light is 150mW/cm 2 (ii) a And removing the polyethylene film after the light irradiation is finished to obtain the boron-containing solid polymer electrolyte film with the thickness of 200 mu m.
The room-temperature conductivity of the boron-containing solid polymer electrolyte prepared in example 6 was 1.09X 10 -4 S/cm, the transference number of lithium ions is 0.60.
Example 7
(1) Mixing 1.125g of polyethylene oxide with the average molecular weight of 300000g/mol, 0.125g of a compound shown in a formula 2 (n is 6), 1g of 2- [2- (2-methoxyethoxy) ethoxy ] ethanol boric acid triester (a compound shown in a formula 4, m is 3) (the mass ratio of a boron-containing crosslinking agent to polyethylene oxide is 3);
(2) 0.5g of the precursor was addedPouring the solution on a polytetrafluoroethylene flat plate, heating at 70 deg.C for 15min, covering the polytetrafluoroethylene flat plate with polyethylene film, hot-pressing the polytetrafluoroethylene flat plate covered with polyethylene film at 1.5MPa for 2min, and irradiating with ultraviolet light at 365nm and 150mW/cm for 8min 2 (ii) a And removing the polyethylene film after the light irradiation is finished to obtain the boron-containing solid polymer electrolyte film with the thickness of 200 mu m.
The room-temperature conductivity of the boron-containing solid polymer electrolyte prepared in example 7 was 7.8X 10 -5 S/cm, the transference number of lithium ions is 0.67.
In conclusion, the boron-containing solid polymer electrolyte prepared by the invention has excellent room-temperature conductivity and lithium ion transference number, and the lithium battery containing the boron-containing solid polymer electrolyte has excellent rate performance, specific capacity and cycle performance.
The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.

Claims (10)

1. A method for preparing a boron-containing solid polymer electrolyte comprises the following steps:
(1) Mixing lithium salt with polyethylene oxide, a boron-containing crosslinking agent and a photoinitiator to obtain a precursor solution;
(2) Sequentially carrying out hot pressing and light irradiation on the precursor solution obtained in the step (1) to obtain a boron-containing solid polymer electrolyte;
the boron-containing crosslinking agent comprises a boron-containing rigid crosslinking agent and a boron-containing flexible crosslinking agent;
the boron-containing rigid cross-linking agent comprises one or more compounds shown in formula 1, formula 2 and formula 3,
Figure DEST_PATH_IMAGE001
；
in the formula 1, the formula 2 and the formula 3, n is an integer of 1 to 50 independently;
the boron-containing flexible cross-linking agent comprises one or more compounds shown in a formula 4,
Figure DEST_PATH_IMAGE002
；
in the formula 4, m is an integer from 1 to 50;
the mass ratio of the boron-containing rigid cross-linking agent to the boron-containing flexible cross-linking agent is (0 to 1): (1 to 2), wherein the mass of the boron-containing rigid cross-linking agent is not 0.
2. The method according to claim 1, wherein the ratio of the amount of the lithium salt to the amount of the substance that is an ethylene oxide monomer for producing polyethylene oxide in the step (1) is 1 (15 to 30).
3. The preparation method according to claim 1, wherein the mass ratio of the boron-containing crosslinking agent to the polyethylene oxide in the step (1) is (1-6): 3.
4. The preparation method according to claim 1, wherein the ratio of the mass of the photoinitiator in the step (1) to the total mass of the polyethylene oxide and the boron-containing crosslinking agent is (1-10): 100.
5. The production method according to claim 1, wherein the hot pressing temperature in the step (2) is 30 to 100 ℃ and the hot pressing pressure is 1 to 2MPa.
6. The production method according to claim 1, wherein a light source of the light irradiation in the step (2) is ultraviolet light.
7. The preparation method according to claim 6, wherein the wavelength of the ultraviolet light is 200 to 380nm.
8. The production method according to claim 1 or 6, wherein the time of light irradiation in the step (2) is 1 to 30min, and the light intensity of light irradiation is 50 to 200mW/cm 2 。
9. A boron-containing solid polymer electrolyte prepared by the preparation method according to any one of claims 1 to 8.
10. A lithium battery, characterized in that the electrolyte of the lithium battery is the boron-containing solid polymer electrolyte prepared by the preparation method of any one of claims 1 to 8 or the boron-containing solid polymer electrolyte of claim 9.
CN202111253975.1A 2021-10-27 2021-10-27 Boron-containing solid polymer electrolyte, preparation method thereof and lithium battery Active CN114188602B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202111253975.1A CN114188602B (en) 2021-10-27 2021-10-27 Boron-containing solid polymer electrolyte, preparation method thereof and lithium battery

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202111253975.1A CN114188602B (en) 2021-10-27 2021-10-27 Boron-containing solid polymer electrolyte, preparation method thereof and lithium battery

Publications (2)

Publication Number Publication Date
CN114188602A CN114188602A (en) 2022-03-15
CN114188602B true CN114188602B (en) 2023-02-10

Family

ID=80601582

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202111253975.1A Active CN114188602B (en) 2021-10-27 2021-10-27 Boron-containing solid polymer electrolyte, preparation method thereof and lithium battery

Country Status (1)

Country Link
CN (1) CN114188602B (en)

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2001229968A (en) * 2000-02-17 2001-08-24 Fujikura Ltd Polymeric electrolyte and manufacturing method therefor
CN106229547A (en) * 2016-09-20 2016-12-14 复旦大学 A kind of boracic solid polymer electrolyte and its preparation method and application
KR20170137279A (en) * 2016-06-03 2017-12-13 서울대학교산학협력단 Electrolyte for secondary battery and secondary battery comprising the same
CN110676509A (en) * 2019-09-02 2020-01-10 东北师范大学 Room-temperature solid polymer electrolyte and preparation method thereof, electrode/electrolyte composite and preparation method and application thereof
CN111430807A (en) * 2020-03-20 2020-07-17 东北师范大学 Solid polymer electrolyte and preparation method thereof

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109004280B (en) * 2018-07-11 2021-06-08 珠海冠宇电池股份有限公司 Preparation method of all-solid-state polymer electrolyte and all-solid-state polymer battery

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2001229968A (en) * 2000-02-17 2001-08-24 Fujikura Ltd Polymeric electrolyte and manufacturing method therefor
KR20170137279A (en) * 2016-06-03 2017-12-13 서울대학교산학협력단 Electrolyte for secondary battery and secondary battery comprising the same
CN106229547A (en) * 2016-09-20 2016-12-14 复旦大学 A kind of boracic solid polymer electrolyte and its preparation method and application
CN110676509A (en) * 2019-09-02 2020-01-10 东北师范大学 Room-temperature solid polymer electrolyte and preparation method thereof, electrode/electrolyte composite and preparation method and application thereof
CN111430807A (en) * 2020-03-20 2020-07-17 东北师范大学 Solid polymer electrolyte and preparation method thereof

Also Published As

Publication number Publication date
CN114188602A (en) 2022-03-15

Similar Documents

Publication Publication Date Title
CN110459798B (en) Sulfide solid electrolyte with core-shell structure, preparation method and solid-state battery
CN103137968B (en) Positive electrode composite material for lithium ion batteries and preparation method thereof
CN105932285B (en) It is a kind of using metal organic frame as the preparation method of the lithium cell cathode material of template
CN111313089B (en) Preparation method of ion conductor/polyethylene oxide composite solid electrolyte based on ultraviolet crosslinking
CN106129337B (en) A kind of preparation method of cathode of lithium iron phosphate lithium ion battery electrode
CN108550835B (en) Lithium iron phosphate/gel electrolyte composite positive electrode material and preparation method thereof, and solid-state lithium battery and preparation method thereof
CN110676510B (en) Modification layer for solid lithium battery electrode/solid electrolyte interface and preparation method and application thereof
CN104466096A (en) Silicon negative electrode plate of lithium ion battery and preparation method of silicon negative electrode plate
CN103137967B (en) A kind of anode composite material of lithium ion battery and preparation method thereof
CN104466142A (en) Silicon/silicon oxycarbide/graphite composite negative electrode material
CN110233285A (en) A method of improving solid state battery interface stability using polymer dielectric
CN113066951B (en) Preparation method and application of flexible self-supporting silicon/carbon nanotube film composite electrode
CN106450424A (en) Polymer composite solid electrolyte and preparation method and application thereof
CN111430807B (en) Solid polymer electrolyte and preparation method thereof
CN104659333A (en) Preparation method of Mg2Si/SiOx/C composite cathode material membrane electrode of lithium ion secondary battery
CN105024050B (en) A kind of bismuth selenide/carbon nano-fiber anode material for sodium-ion battery and preparation method thereof
CN114373986A (en) Polymer solid electrolyte membrane, preparation method thereof and all-solid-state battery
CN114188602B (en) Boron-containing solid polymer electrolyte, preparation method thereof and lithium battery
CN112242554A (en) Composite solid electrolyte membrane, preparation method thereof and solid battery
JP7413482B2 (en) Manufacturing method for lithium ion battery negative electrode material
CN111916680A (en) Preparation method of fluorinated polymer modified battery electrode and application of fluorinated polymer modified battery electrode in battery field
CN110994016A (en) Polymer solid electrolyte and preparation method and application thereof
CN111040061B (en) Solid sodium ion electrolyte, preparation method thereof and all-solid-state sodium battery
CN115498165A (en) Black phosphorus-based composite electrode and preparation method and application thereof
CN114843599A (en) Borate cross-linked self-repairing polymer electrolyte and preparation method and application thereof

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant