CN111816917A - Composite polymer solid electrolyte and preparation method thereof - Google Patents
Composite polymer solid electrolyte and preparation method thereof Download PDFInfo
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- CN111816917A CN111816917A CN202010716292.4A CN202010716292A CN111816917A CN 111816917 A CN111816917 A CN 111816917A CN 202010716292 A CN202010716292 A CN 202010716292A CN 111816917 A CN111816917 A CN 111816917A
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- 239000007784 solid electrolyte Substances 0.000 title claims abstract description 58
- 229920000642 polymer Polymers 0.000 title claims abstract description 55
- 239000002131 composite material Substances 0.000 title claims abstract description 47
- 238000002360 preparation method Methods 0.000 title claims abstract description 20
- 239000004952 Polyamide Substances 0.000 claims abstract description 53
- 229920002647 polyamide Polymers 0.000 claims abstract description 53
- 229910052744 lithium Inorganic materials 0.000 claims abstract description 51
- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 claims abstract description 48
- 239000012528 membrane Substances 0.000 claims abstract description 47
- 229920003171 Poly (ethylene oxide) Polymers 0.000 claims abstract description 38
- HBBGRARXTFLTSG-UHFFFAOYSA-N Lithium ion Chemical compound [Li+] HBBGRARXTFLTSG-UHFFFAOYSA-N 0.000 claims abstract description 36
- 229910001416 lithium ion Inorganic materials 0.000 claims abstract description 36
- 239000011259 mixed solution Substances 0.000 claims abstract description 28
- 229910003002 lithium salt Inorganic materials 0.000 claims abstract description 25
- 159000000002 lithium salts Chemical class 0.000 claims abstract description 25
- 239000002904 solvent Substances 0.000 claims abstract description 21
- 239000003960 organic solvent Substances 0.000 claims abstract description 16
- 238000002791 soaking Methods 0.000 claims abstract description 11
- 238000002156 mixing Methods 0.000 claims abstract description 10
- WEVYAHXRMPXWCK-UHFFFAOYSA-N Acetonitrile Chemical compound CC#N WEVYAHXRMPXWCK-UHFFFAOYSA-N 0.000 claims description 42
- 239000010935 stainless steel Substances 0.000 claims description 26
- 229910001220 stainless steel Inorganic materials 0.000 claims description 26
- -1 lithium hexafluorophosphate Chemical compound 0.000 claims description 11
- 239000005518 polymer electrolyte Substances 0.000 claims description 11
- 238000000034 method Methods 0.000 claims description 10
- 239000000758 substrate Substances 0.000 claims description 10
- 239000013354 porous framework Substances 0.000 claims description 5
- OIFBSDVPJOWBCH-UHFFFAOYSA-N Diethyl carbonate Chemical compound CCOC(=O)OCC OIFBSDVPJOWBCH-UHFFFAOYSA-N 0.000 claims description 3
- KMTRUDSVKNLOMY-UHFFFAOYSA-N Ethylene carbonate Chemical compound O=C1OCCO1 KMTRUDSVKNLOMY-UHFFFAOYSA-N 0.000 claims description 3
- 229910052782 aluminium Inorganic materials 0.000 claims description 3
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims description 3
- IEJIGPNLZYLLBP-UHFFFAOYSA-N dimethyl carbonate Chemical compound COC(=O)OC IEJIGPNLZYLLBP-UHFFFAOYSA-N 0.000 claims description 3
- 239000011521 glass Substances 0.000 claims description 3
- 229910001496 lithium tetrafluoroborate Inorganic materials 0.000 claims description 3
- 239000005020 polyethylene terephthalate Substances 0.000 claims description 3
- 239000004810 polytetrafluoroethylene Substances 0.000 claims description 3
- 229920001343 polytetrafluoroethylene Polymers 0.000 claims description 3
- 238000004519 manufacturing process Methods 0.000 claims 1
- 210000001787 dendrite Anatomy 0.000 abstract description 9
- 239000003792 electrolyte Substances 0.000 description 38
- 210000004027 cell Anatomy 0.000 description 13
- QSZMZKBZAYQGRS-UHFFFAOYSA-N lithium;bis(trifluoromethylsulfonyl)azanide Chemical compound [Li+].FC(F)(F)S(=O)(=O)[N-]S(=O)(=O)C(F)(F)F QSZMZKBZAYQGRS-UHFFFAOYSA-N 0.000 description 11
- 229910003473 lithium bis(trifluoromethanesulfonyl)imide Inorganic materials 0.000 description 10
- 239000007774 positive electrode material Substances 0.000 description 5
- 230000000052 comparative effect Effects 0.000 description 4
- 230000001351 cycling effect Effects 0.000 description 4
- 150000002500 ions Chemical class 0.000 description 4
- 238000004502 linear sweep voltammetry Methods 0.000 description 4
- 239000000203 mixture Substances 0.000 description 4
- 230000010287 polarization Effects 0.000 description 4
- 239000011148 porous material Substances 0.000 description 4
- 238000003756 stirring Methods 0.000 description 4
- 238000002474 experimental method Methods 0.000 description 3
- 238000004880 explosion Methods 0.000 description 3
- 238000001000 micrograph Methods 0.000 description 3
- 230000003287 optical effect Effects 0.000 description 3
- 238000000429 assembly Methods 0.000 description 2
- 230000000712 assembly Effects 0.000 description 2
- 238000002425 crystallisation Methods 0.000 description 2
- 230000008025 crystallization Effects 0.000 description 2
- 238000005034 decoration Methods 0.000 description 2
- 238000003475 lamination Methods 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- BVKZGUZCCUSVTD-UHFFFAOYSA-L Carbonate Chemical compound [O-]C([O-])=O BVKZGUZCCUSVTD-UHFFFAOYSA-L 0.000 description 1
- IAYPIBMASNFSPL-UHFFFAOYSA-N Ethylene oxide Chemical compound C1CO1 IAYPIBMASNFSPL-UHFFFAOYSA-N 0.000 description 1
- 239000004698 Polyethylene Substances 0.000 description 1
- 239000004743 Polypropylene Substances 0.000 description 1
- 239000013543 active substance Substances 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 238000000354 decomposition reaction Methods 0.000 description 1
- 238000010494 dissociation reaction Methods 0.000 description 1
- 230000005593 dissociations Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 229910003480 inorganic solid Inorganic materials 0.000 description 1
- 238000011031 large-scale manufacturing process Methods 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 239000011159 matrix material Substances 0.000 description 1
- 239000012466 permeate Substances 0.000 description 1
- 229920000573 polyethylene Polymers 0.000 description 1
- 229920001155 polypropylene Polymers 0.000 description 1
- 239000000047 product Substances 0.000 description 1
- 230000003014 reinforcing effect Effects 0.000 description 1
- 239000000243 solution Substances 0.000 description 1
- 239000007858 starting material Substances 0.000 description 1
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- 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
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- 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
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- 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
- H01M10/058—Construction or manufacture
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- 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
- H01M10/42—Methods or arrangements for servicing or maintenance of secondary cells or secondary half-cells
- H01M10/4235—Safety or regulating additives or arrangements in electrodes, separators or electrolyte
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- 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
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- 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
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- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
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Abstract
The invention relates to the technical field of lithium ion batteries, in particular to a composite polymer solid electrolyte and a preparation method thereof. The preparation method comprises the following steps: mixing polyethylene oxide, lithium salt and an organic solvent to obtain a mixed solution; and soaking the porous polyamide membrane in the mixed solution, taking out the soaked porous polyamide membrane, and volatilizing the solvent to obtain the composite polymer solid electrolyte. The polymer solid electrolyte prepared by the invention has high conductivity and high strength, can inhibit the growth of lithium dendrites, and has good thermal stability and incombustible characteristic and high safety.
Description
Technical Field
The invention relates to the technical field of lithium ion batteries, in particular to a composite polymer solid electrolyte and a preparation method thereof.
Background
The lithium ion battery has the advantages of high energy density, long cycle life, small self-discharge effect, environmental friendliness and the like, and is widely applied to the fields of mobile phones, digital cameras, electric automobiles and the like, so that social progress is greatly promoted. However, liquid lithium ion batteries are currently in common use, wherein the electrolyte contains a carbonate organic solvent which is extremely flammable, and such solvents may cause a series of safety problems due to decomposition of the organic solvent, leakage of the electrolyte and burning of the electrolyte during the use of the batteries. In addition, at present, polyethylene and polypropylene diaphragms are mainly used for avoiding the contact of positive and negative electrodes of the lithium ion battery, the strength of the lithium ion battery is low, lithium dendrites generated in the battery circulation process easily pierce the diaphragms, the battery is short-circuited, and the safety problem is further increased. Therefore, the solid electrolyte is used for replacing the traditional electrolyte and a membrane system, and has important significance.
Solid electrolytes are generally classified into two types, polymer solid electrolytes and inorganic solid electrolytes. In contrast, the polymer solid electrolyte has the advantages of high flexibility and low cost, so that the polymer solid electrolyte has the advantage of large-scale production. Among the polymer solid electrolytes, polyethylene oxide has a high dielectric constant, which facilitates the dissociation of lithium salts, and thus its combination with lithium salts is the most commonly used polymer solid electrolyte system. However, the intrinsic lithium ion conductivity is not high (10) due to slow movement of segments for transporting lithium ions in the polyethylene oxide crystalline region-7～10-6S cm-1At 25 ℃ C. Furthermore, polyethylene oxide is low in strength, unable to inhibit lithium dendrite growth, and flammable, which further hinders its use.
Disclosure of Invention
The invention aims to provide a composite polymer solid electrolyte and a preparation method thereof, and the prepared polymer solid electrolyte has high conductivity, high strength, good thermal stability and incombustible characteristic and high safety, and can inhibit the growth of lithium dendrites.
In order to achieve the above object, the present invention provides the following technical solutions:
the invention provides a preparation method of a composite polymer solid electrolyte, which comprises the following steps: mixing polyethylene oxide, lithium salt and an organic solvent to obtain a mixed solution;
and soaking the porous polyamide membrane in the mixed solution, taking out the soaked porous polyamide membrane, and removing the solvent to obtain the composite polymer solid electrolyte.
Preferably, the lithium salt comprises lithium bistrifluoromethanesulfonylimide, lithium hexafluorophosphate or lithium tetrafluoroborate.
Preferably, the organic solvent comprises acetonitrile, ethylene carbonate, diethyl carbonate or dimethyl carbonate.
Preferably, the molar ratio of the polyethylene oxide to the lithium salt is (6-12) to 1; the mass ratio of the total mass of the polyethylene oxide and the lithium salt to the organic solvent is 1 (30-200).
Preferably, the thickness of the porous polyamide membrane is 10-200 mu m, and the porosity is 20-80%.
Preferably, the mass ratio of the porous polyamide membrane to the mixed solution is 1 (10-200).
Preferably, the soaking time is 12-72 hours.
Preferably, the solvent removing conditions include: volatilizing for 12-48 h under vacuum condition, wherein the volatilizing temperature is 25-80 ℃.
Preferably, the soaked polyamide film is taken out and then placed on a substrate for solvent volatilization; the substrate is stainless steel, aluminum, polytetrafluoroethylene, glass, PET, a lithium ion battery positive plate or a lithium ion battery negative plate.
The invention provides a composite polymer solid electrolyte prepared by the preparation method in the technical scheme, which comprises a porous polyamide membrane and a polymer electrolyte, wherein the polymer electrolyte is filled into a porous framework of the porous polyamide membrane; the polymer electrolyte is composed of polyethylene oxide and lithium salt.
The invention provides a preparation method of a composite polymer solid electrolyte, which comprises the following steps: mixing polyethylene oxide, lithium salt and an organic solvent to obtain a mixed solution; and soaking the porous polyamide membrane in the mixed solution, taking out the soaked porous polyamide membrane, and removing the solvent to obtain the composite polymer solid electrolyte.
The invention utilizes the porous characteristic of polyamide to limit the expansion of polyethylene oxide crystallization area, thereby improving the conductivity of polyethylene oxide, and the results of the examples show that the conductivity of the composite polymer solid electrolyte prepared by the invention can reach 2.05 multiplied by 10 at 30 DEG C-4S cm-1The transference number of the lithium ion is 0.53, the electrochemical stability window of the lithium ion is about 4.7V, and the requirement that the lithium ion battery is matched with a high-voltage positive active material can be met. Because the polyamide has quite high Young modulus, the prepared composite polymer solid electrolyte has higher strength (the Young modulus is up to 1030MPa), and can effectively inhibit the growth of lithium dendrites; and due to the higher thermal stability and non-flammable characteristic of polyamide, the safety of the battery is improved.
In addition, the composite polymer solid electrolyte prepared by the invention also has excellent flexibility, ensures the smooth preparation of the bendable soft package battery, and can still maintain normal discharge performance under the conditions of extreme deformation and puncture.
Drawings
FIG. 1 is a scanning electron microscope image of the polyamide porous membrane of example 1 before and after the lamination;
FIG. 2 is a composite polymer solid electrolyte sheet morphology and flexibility display prepared in example 1;
FIG. 3 is a graph showing the change in ionic conductivity with temperature of a composite polymer solid electrolyte prepared in example 1;
FIG. 4 shows the results of lithium ion transference number test of the composite polymer solid electrolyte prepared in example 1;
FIG. 5 shows electrochemical window test results of a composite polymer solid electrolyte prepared in example 1;
FIG. 6 shows that the composite polymer solid electrolyte prepared in example 1 has a temperature of 10mm min-1Stress-strain curve at tensile rate;
FIG. 7 is a scanning electron microscope image of the surface of a lithium sheet after cycling of a lithium/lithium symmetric battery with a composite polymer solid electrolyte prepared in example 1;
fig. 8 is an optical photograph of the composite polymer solid electrolyte prepared in example 1 when a flame is approached and after the flame is removed, respectively.
Fig. 9 is an optical photograph of a pouch cell of the composite polymer solid electrolyte assembly prepared in example 1, which normally lights up an LED lamp in normal, bent, rolled, and punctured conditions, respectively.
Detailed Description
The invention provides a preparation method of a composite polymer solid electrolyte, which comprises the following steps: mixing polyethylene oxide, lithium salt and an organic solvent to obtain a mixed solution;
and soaking the porous polyamide membrane in the mixed solution, taking out the soaked porous polyamide membrane, and removing the solvent to obtain the composite polymer solid electrolyte.
In the present invention, the starting materials used are all commercially available products well known in the art, unless otherwise specified.
According to the invention, polyethylene oxide, lithium salt and an organic solvent are mixed to obtain a mixed solution. In the present invention, the lithium salt preferably includes lithium bistrifluoromethanesulfonylimide, lithium hexafluorophosphate, or lithium tetrafluoroborate, more preferably lithium bistrifluoromethanesulfonylimide; the organic solvent preferably comprises acetonitrile, ethylene carbonate, diethyl carbonate or dimethyl carbonate, more preferably acetonitrile; the acetonitrile is preferably anhydrous acetonitrile. In the invention, the molar ratio of the polyethylene oxide to the lithium salt is preferably (6-12) to 1, more preferably (7-11): 1, more preferably (8-10): 1; the mass ratio of the total mass of the polyethylene oxide and the lithium salt to the organic solvent is preferably 1 (30-200), more preferably 1 (50-180), even more preferably 1 (70-160), and even more preferably 1 (90-140). In the present invention, a lithium salt serves as a source of lithium ions in the electrolyte; polyethylene oxide is used as a polymer electrolyte matrix and is used for dissociating lithium salt and conducting lithium ions; the solvent is used to dissolve the polyethylene oxide and lithium salt.
The invention has no special requirement on the mixing mode of the polyethylene oxide, the lithium salt and the organic solvent, and the polyethylene oxide, the lithium salt and the organic solvent can be uniformly mixed.
After the mixed solution is obtained, the porous polyamide membrane is soaked in the mixed solution, then the soaked porous polyamide membrane is taken out, and the solvent is removed to obtain the composite polymer solid electrolyte.
In the invention, the thickness of the porous polyamide membrane is preferably 10-200 μm, more preferably 30-160 μm, and further preferably 40-120 μm; the porosity is preferably 20-80%, more preferably 30-70%, and further preferably 40-70%; the pore diameter is preferably 0.1 to 10 μm, more preferably 0.3 to 5 μm, and further preferably 0.5 to 2 μm. In the present invention, the porous polyamide serves as a reinforcing skeleton.
In the present invention, the mass ratio of the porous polyamide membrane to the mixed solution is preferably 1 (10-200), more preferably 1 (20-150), and still more preferably 1 (30-100). In the invention, the soaking time is preferably 12-72 hours, more preferably 20-70 hours, further preferably 30-60 hours, and further preferably 40-50 hours. In the present invention, the soaking is preferably performed at normal temperature. In the soaking process, the mixed solution permeates into the porous framework of the porous polyamide membrane.
After the soaking is finished, the soaked porous polyamide membrane is taken out, and the solvent is removed to obtain the composite polymer solid electrolyte. The invention preferably takes out the soaked porous polyamide membrane and places the porous polyamide membrane on a substrate to remove the solvent. In the invention, the substrate is preferably stainless steel, aluminum, polytetrafluoroethylene, glass, PET, a lithium ion battery positive plate or a lithium ion battery negative plate. In the present invention, the solvent removal conditions preferably include: volatilizing for 12-48 h under a vacuum condition, wherein the volatilizing temperature is 25-80 ℃; further, the volatilization temperature is more preferably 40-70 ℃, and further preferably 50-60 ℃; the time for volatilization is more preferably 16 to 40 hours, and still more preferably 20 to 30 hours. The invention carries out solvent volatilization under the vacuum condition, and aims to ensure that the solvent is fully volatilized.
The invention provides a composite polymer solid electrolyte prepared by the preparation method in the scheme, which comprises a porous polyamide membrane and a polymer electrolyte, wherein the polymer electrolyte is filled into a porous framework of the porous polyamide membrane; the polymer electrolyte is composed of ethylene oxide and a lithium salt. The invention utilizes the porous characteristic of polyamide to limit the expansion of polyethylene oxide crystallization area, thereby improving the conductivity of polyethylene oxide, and the results of the examples show that the conductivity of the composite polymer solid electrolyte prepared by the invention can reach 2.05 multiplied by 10 at 30 DEG C-4S cm-1The transference number of the lithium ion is 0.53, the electrochemical stability window of the lithium ion is about 4.7V, and the requirement that the lithium ion battery is matched with a high-voltage positive active material can be met. Because the polyamide has quite high Young modulus, the prepared composite polymer solid electrolyte has very high strength (the Young modulus is up to 1030MPa), and can effectively inhibit the growth of lithium dendrites; and due to the higher thermal stability and non-flammable characteristic of polyamide, the safety of the battery is improved.
The composite polymer solid electrolyte and the method for preparing the same according to the present invention will be described in detail with reference to examples, but they should not be construed as limiting the scope of the present invention.
Example 1
Preparation of composite polymer solid electrolyte:
(1) uniformly mixing polyethylene oxide, lithium bis (trifluoromethanesulfonyl) imide and anhydrous acetonitrile, and stirring to obtain a mixed solution. Wherein the molar ratio of the polyethylene oxide to the lithium bis (trifluoromethanesulfonyl) imide is 12:1, and the mass ratio of the mixture of the polyethylene oxide and the lithium bis (trifluoromethanesulfonyl) imide to the anhydrous acetonitrile is 1: 50.
(2) A porous polyamide membrane (thickness 41 μm, pore size 1 μm, porosity 63%) was soaked in the mixed solution for 48 h. Wherein the mass ratio of the porous polyamide membrane to the mixed solution is 1: 20.
(3) And taking out the soaked polyamide membrane, placing the polyamide membrane on a flat stainless steel substrate, and volatilizing the solvent in vacuum for 12 hours to obtain the composite polymer solid electrolyte.
FIG. 1 is a scanning electron microscope image of the polyamide porous membrane of example 1 before and after the lamination; in the figure 1, the polymer electrolyte (polyethylene oxide and lithium bistrifluoromethanesulfonimide) actually enters the porous framework of the polyamide before the left side is compounded and after the right side is compounded.
Fig. 2 shows the morphology and flexibility of the composite polymer solid electrolyte sheet prepared in this example, which shows good flexibility.
The composite polymer solid electrolyte obtained in this example was used to assemble stainless steel-plugged cells (stainless steel/electrolyte/stainless steel) which were subjected to electrochemical impedance tests at different temperatures (25 ℃, 30 ℃, 40 ℃, 50 ℃, 60 ℃, 70 ℃) and the test results are shown in fig. 3. It was calculated from FIG. 3 that it had an ionic conductivity of 2.05X 10 at 30 deg.C-4S cm-1Completely meets the requirement of the lithium ion battery on the ion conductivity of the electrolyte.
The lithium plate/electrolyte/lithium plate cell was assembled and subjected to direct current polarization and electrochemical impedance test (0.01Hz to 1000000Hz) at room temperature (25 ℃), and the test results are shown in fig. 4. The transference number of lithium ions was calculated from fig. 4 to be 0.53.
The electrochemical stability of the lithium/stainless steel battery assembled with the composite polymer solid electrolyte obtained in this example was measured by linear sweep voltammetry (voltage range 1.8V to 6V), and the results are shown in fig. 5. The electrochemical window of the lithium ion battery obtained from fig. 5 is about 4.7V, and the lithium ion battery can meet the requirement of matching with a high-voltage positive active material.
A dumbbell-shaped test specimen (the width of the test specimen is 4mm, and the tensile rate is 10mm/min) prepared from the composite polymer solid electrolyte obtained in the example is used for mechanical property test, and the test result is shown in FIG. 6. The Young modulus of the alloy is up to 1030MPa calculated from the figure 6.
Scanning electron microscope observation of the surface of the lithium sheet after cycling of the lithium/lithium symmetric battery assembled with the composite polymer solid electrolyte obtained in this example was carried out, and the results are shown in fig. 7. Fig. 7 shows that the surface was smooth with no evidence of lithium dendrite growth.
The composite polymer solid electrolyte obtained in this example was subjected to an ignition test, and the results are shown in FIG. 8. As can be seen from fig. 8, the electrolyte membrane did not burn after the flame was approached and removed, demonstrating that the electrolyte has a certain flame retardancy, which can reduce the risk of explosion of the battery.
Deformation and puncture experiments were performed on the pouch cell of the composite polymer solid electrolyte assembly obtained in this example, and fig. 9 is an optical photograph of the pouch cell of the composite polymer solid electrolyte assembly prepared in this example, in which the LED lamp was normally turned on under normal, bent, curled, and punctured conditions, respectively, showing that the cell can still maintain normal performance under extreme deformation and puncture conditions.
Example 2
Preparation of composite polymer solid electrolyte:
(1) uniformly mixing polyethylene oxide, lithium bistrifluoromethanesulfonylimide and anhydrous acetonitrile, and stirring to obtain a mixed solution. Wherein the molar ratio of the polyethylene oxide to the lithium bis (trifluoromethanesulfonyl) imide is 10:1, and the mass ratio of the mixture of the polyethylene oxide and the lithium bis (trifluoromethanesulfonyl) imide to the anhydrous acetonitrile is 1: 100.
(2) A porous polyamide membrane (thickness 41 μm, pore size 1 μm, porosity 63%) was soaked in the mixed solution for 48 h. Wherein the mass ratio of the porous polyamide membrane to the mixed solution is 1: 10.
(3) And taking out the soaked polyamide membrane, placing the polyamide membrane on a flat stainless steel substrate, and volatilizing the solvent in vacuum for 18 hours to obtain the composite polymer solid electrolyte.
Using the electrolyte obtained in this example, a stainless steel-made plugged cell (stainless steel/electrolyte/stainless steel) was subjected to electrochemical impedance tests at different temperatures (25 ℃, 30 ℃, 40 ℃, 50 ℃, 60 ℃, 70 ℃) and the ionic conductivity at 30 ℃ was calculated to be 2.03X 10-4S cm-1Completely meets the requirement of the lithium ion battery on the ion conductivity of the electrolyte. Assembling the lithium plate/electrolyte/lithium plate battery, carrying out direct current polarization and electrochemical impedance test (0.01 Hz-1000000 Hz) at room temperature (25 ℃), and calculating to obtain the transference number of lithium ions of 0.53.
By adopting the lithium/stainless steel battery with the electrolyte assembly obtained in the embodiment, the electrochemical stability of the lithium/stainless steel battery to lithium metal is tested by a linear sweep voltammetry method (the voltage range is 1.8V-6V), the electrochemical window of the lithium/stainless steel battery to lithium is about 4.6V, and the lithium/stainless steel battery can meet the requirement that the lithium ion battery is matched with a positive active material with higher voltage.
The electrolyte obtained in the embodiment is used for preparing a dumbbell-shaped sample (the sample width is 4mm, the tensile rate is 10mm/min) to carry out mechanical property test, and the Young modulus of the dumbbell-shaped sample is up to 1017 MPa.
The surface of the lithium sheet of the lithium/lithium symmetric battery with the electrolyte assembly obtained in the embodiment after cycling is observed by a scanning electron microscope, and the surface is flat without the evidence of lithium dendrite growth.
The electrolyte obtained in the embodiment is subjected to ignition experiments, and the electrolyte membrane does not burn after the flame is close to and removed, so that the electrolyte is proved to have certain flame retardance, and the risk of burning and explosion of the battery can be reduced.
Deformation and puncture tests were performed on the pouch cells of the electrolyte assemblies obtained in this example, and the cells were able to maintain normal performance even under extreme deformation and puncture conditions.
Example 3
Preparation of composite polymer solid electrolyte:
(1) uniformly mixing polyethylene oxide, lithium bistrifluoromethanesulfonylimide and anhydrous acetonitrile, and stirring to obtain a mixed solution. Wherein the molar ratio of the polyethylene oxide to the lithium bis (trifluoromethanesulfonyl) imide is 6:1, and the mass ratio of the mixture of the polyethylene oxide and the lithium bis (trifluoromethanesulfonyl) imide to the anhydrous acetonitrile is 1: 150.
(2) A porous polyamide membrane (thickness 41 μm, pore size 1 μm, porosity 63%) was soaked in the mixed solution for 48 h. Wherein the mass ratio of the porous polyamide membrane to the mixed solution is 1: 70.
(3) And taking out the soaked polyamide membrane, placing the polyamide membrane on a flat stainless steel substrate, and volatilizing the solvent in vacuum for 36 hours to obtain the composite polymer solid electrolyte.
Using the electrolyte obtained in this example, a stainless-steel-made plugged cell (stainless steel/electrolyte/stainless steel) was assembled and subjected to various temperatures (25 ℃, 30 ℃, 40 ℃, 50 ℃, 60 ℃, 70 ℃)The electrochemical impedance test of (1) is carried out, and the ionic conductivity of the material at 30 ℃ is calculated to be 1.98 multiplied by 10-4S cm-1Completely meets the requirement of the lithium ion battery on the ion conductivity of the electrolyte. Assembling the lithium plate/electrolyte/lithium plate battery, carrying out direct current polarization and electrochemical impedance test (0.01 Hz-1000000 Hz) at room temperature (25 ℃), and calculating to obtain the transference number of lithium ions of 0.53.
By adopting the lithium/stainless steel battery with the electrolyte assembly obtained in the embodiment, the electrochemical stability of the lithium/stainless steel battery to lithium metal is tested by a linear sweep voltammetry method (the voltage range is 1.8V-6V), the electrochemical window of the lithium/stainless steel battery to lithium is about 4.7V, and the lithium/stainless steel battery can meet the requirement that the lithium ion battery is matched with a positive active material with higher voltage.
A dumbbell-shaped test specimen (the width of the test specimen is 4mm, and the tensile rate is 10mm/min) prepared by using the electrolyte obtained in the embodiment is used for carrying out mechanical property test, and the Young modulus of the test specimen is up to 1023 MPa.
The surface of the lithium sheet of the lithium/lithium symmetric battery with the electrolyte assembly obtained in the embodiment after cycling is observed by a scanning electron microscope, and the surface is flat without the evidence of lithium dendrite growth.
The electrolyte obtained in the embodiment is subjected to ignition experiments, and the electrolyte membrane does not burn after the flame is close to and removed, so that the electrolyte is proved to have certain flame retardance, and the risk of burning and explosion of the battery can be reduced.
Deformation and puncture tests were performed on the pouch cells of the electrolyte assemblies obtained in this example, and the cells were able to maintain normal performance even under extreme deformation and puncture conditions.
Comparative example
The difference from the example 1 is only that the porous polyamide membrane is not adopted, and the specific steps are as follows:
(1) uniformly mixing polyethylene oxide, lithium bis (trifluoromethanesulfonyl) imide and anhydrous acetonitrile, and stirring to obtain a mixed solution. Wherein the molar ratio of the polyethylene oxide to the lithium bis (trifluoromethanesulfonyl) imide is 12:1, and the mass ratio of the mixture of the polyethylene oxide and the lithium bis (trifluoromethanesulfonyl) imide to the anhydrous acetonitrile is 1: 50.
(2) And coating the mixed solution on a stainless steel substrate, and volatilizing the solvent in vacuum for 12h to obtain the polymer solid electrolyte.
Using the electrolyte obtained in this comparative example, a stainless-steel-made plugged cell (stainless steel/electrolyte/stainless steel) was subjected to electrochemical impedance tests at different temperatures (25 ℃, 30 ℃, 40 ℃, 50 ℃, 60 ℃, 70 ℃) to calculate an ionic conductivity of 5.53X 10 at 30 ℃-5S cm-1It is difficult to meet the requirements of lithium ion batteries for electrolyte ion conductivity.
Assembling the lithium plate/electrolyte/lithium plate battery, carrying out direct current polarization and electrochemical impedance test (0.01 Hz-1000000 Hz) at room temperature (25 ℃) and calculating to obtain the transference number of lithium ions of 0.34.
The lithium/stainless steel battery assembled by the electrolyte obtained by the comparative example is tested for the electrochemical stability of lithium metal by a linear sweep voltammetry method (the voltage range is 1.8V-6V), the electrochemical window of the lithium/stainless steel battery is about 3.9V, and the requirement that the lithium ion battery is matched with a positive electrode active substance with higher voltage is difficult to meet.
The electrolyte obtained in the comparative example is used for preparing a dumbbell-shaped sample (the sample width is 4mm, the tensile rate is 10mm/min) to carry out mechanical property test, and the Young modulus is only 0.02 MPa.
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 preparation method of a composite polymer solid electrolyte is characterized by comprising the following steps: mixing polyethylene oxide, lithium salt and an organic solvent to obtain a mixed solution;
and soaking the porous polyamide membrane in the mixed solution, taking out the soaked porous polyamide membrane, and removing the solvent to obtain the composite polymer solid electrolyte.
2. The method of claim 1, wherein the lithium salt comprises lithium bistrifluoromethanesulfonylimide, lithium hexafluorophosphate, or lithium tetrafluoroborate.
3. The production method according to claim 1 or 2, characterized in that the organic solvent comprises acetonitrile, ethylene carbonate, diethyl carbonate, or dimethyl carbonate.
4. The preparation method according to claim 3, wherein the molar ratio of the polyethylene oxide to the lithium salt is (6-12): 1; the mass ratio of the total mass of the polyethylene oxide and the lithium salt to the organic solvent is 1 (30-200).
5. The method according to claim 1, wherein the porous polyamide membrane has a thickness of 10 to 200 μm and a porosity of 20 to 80%.
6. The preparation method according to claim 1 or 5, wherein the mass ratio of the porous polyamide membrane to the mixed solution is 1 (10-200).
7. The preparation method according to claim 1, wherein the soaking time is 12-72 hours.
8. The method of claim 1, wherein the solvent removal conditions comprise: volatilizing for 12-48 h under vacuum condition, wherein the volatilizing temperature is 25-80 ℃.
9. The method according to claim 1, wherein the soaked polyamide film is taken out and placed on a substrate to volatilize the solvent; the substrate is stainless steel, aluminum, polytetrafluoroethylene, glass, PET, a lithium ion battery positive plate or a lithium ion battery negative plate.
10. The composite polymer solid electrolyte prepared by the preparation method of any one of claims 1 to 9, which comprises a porous polyamide membrane and a polymer electrolyte, wherein the polymer electrolyte is filled into a porous framework of the porous polyamide membrane; the polymer electrolyte is composed of polyethylene oxide and lithium salt.
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102324559A (en) * | 2011-09-16 | 2012-01-18 | 中国科学院化学研究所 | A kind of polymer dielectric and preparation method thereof and application |
| KR20160013631A (en) * | 2014-07-28 | 2016-02-05 | 울산과학기술원 산학협력단 | Solid electrolytes for all solid state rechargeable lithium battery, methods for manufacturing the same, and all solid state rechargeable lithium battery including the same |
| CN107658500A (en) * | 2017-08-07 | 2018-02-02 | 南昌大学 | A kind of original position prepares method and the application of flexible lithium ion battery polymer dielectric |
| CN110071327A (en) * | 2019-04-10 | 2019-07-30 | 深圳新宙邦科技股份有限公司 | A kind of solid electrolyte and polymer Li-ion battery |
| CN110770959A (en) * | 2017-06-27 | 2020-02-07 | 株式会社日本触媒 | Electrolyte composition, electrolyte membrane, electrode, battery, and method for evaluating electrolyte composition |
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Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102324559A (en) * | 2011-09-16 | 2012-01-18 | 中国科学院化学研究所 | A kind of polymer dielectric and preparation method thereof and application |
| KR20160013631A (en) * | 2014-07-28 | 2016-02-05 | 울산과학기술원 산학협력단 | Solid electrolytes for all solid state rechargeable lithium battery, methods for manufacturing the same, and all solid state rechargeable lithium battery including the same |
| CN110770959A (en) * | 2017-06-27 | 2020-02-07 | 株式会社日本触媒 | Electrolyte composition, electrolyte membrane, electrode, battery, and method for evaluating electrolyte composition |
| CN107658500A (en) * | 2017-08-07 | 2018-02-02 | 南昌大学 | A kind of original position prepares method and the application of flexible lithium ion battery polymer dielectric |
| CN110071327A (en) * | 2019-04-10 | 2019-07-30 | 深圳新宙邦科技股份有限公司 | A kind of solid electrolyte and polymer Li-ion battery |
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