CN114335883A - Lithium ion battery diaphragm with high heat exchange stability and preparation method thereof - Google Patents
Lithium ion battery diaphragm with high heat exchange stability and preparation method thereof Download PDFInfo
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- CN114335883A CN114335883A CN202111481063.XA CN202111481063A CN114335883A CN 114335883 A CN114335883 A CN 114335883A CN 202111481063 A CN202111481063 A CN 202111481063A CN 114335883 A CN114335883 A CN 114335883A
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- HBBGRARXTFLTSG-UHFFFAOYSA-N Lithium ion Chemical compound [Li+] HBBGRARXTFLTSG-UHFFFAOYSA-N 0.000 title claims abstract description 40
- 229910001416 lithium ion Inorganic materials 0.000 title claims abstract description 40
- 238000002360 preparation method Methods 0.000 title claims abstract description 18
- 239000011248 coating agent Substances 0.000 claims abstract description 64
- 238000000576 coating method Methods 0.000 claims abstract description 64
- -1 polyethylene Polymers 0.000 claims abstract description 40
- 239000004698 Polyethylene Substances 0.000 claims abstract description 31
- 229920000573 polyethylene Polymers 0.000 claims abstract description 31
- 239000002002 slurry Substances 0.000 claims abstract description 31
- 239000012982 microporous membrane Substances 0.000 claims abstract description 30
- 239000002033 PVDF binder Substances 0.000 claims abstract description 28
- 229920002981 polyvinylidene fluoride Polymers 0.000 claims abstract description 28
- 239000004952 Polyamide Substances 0.000 claims abstract description 15
- 229920002647 polyamide Polymers 0.000 claims abstract description 15
- 238000001035 drying Methods 0.000 claims description 21
- 238000003756 stirring Methods 0.000 claims description 20
- PHTQWCKDNZKARW-UHFFFAOYSA-N isoamylol Chemical compound CC(C)CCO PHTQWCKDNZKARW-UHFFFAOYSA-N 0.000 claims description 18
- SECXISVLQFMRJM-UHFFFAOYSA-N N-Methylpyrrolidone Chemical compound CN1CCCC1=O SECXISVLQFMRJM-UHFFFAOYSA-N 0.000 claims description 17
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims description 15
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 claims description 15
- 238000000034 method Methods 0.000 claims description 15
- 229910017604 nitric acid Inorganic materials 0.000 claims description 15
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 14
- 239000003960 organic solvent Substances 0.000 claims description 12
- 238000002156 mixing Methods 0.000 claims description 11
- 238000005406 washing Methods 0.000 claims description 11
- 239000007774 positive electrode material Substances 0.000 claims description 10
- 238000007756 gravure coating Methods 0.000 claims description 8
- 239000012528 membrane Substances 0.000 claims description 8
- 230000007935 neutral effect Effects 0.000 claims description 8
- 239000008367 deionised water Substances 0.000 claims description 7
- 229910021641 deionized water Inorganic materials 0.000 claims description 7
- QHGJSLXSVXVKHZ-UHFFFAOYSA-N dilithium;dioxido(dioxo)manganese Chemical compound [Li+].[Li+].[O-][Mn]([O-])(=O)=O QHGJSLXSVXVKHZ-UHFFFAOYSA-N 0.000 claims description 7
- 238000000605 extraction Methods 0.000 claims description 7
- 238000002791 soaking Methods 0.000 claims description 7
- 239000000203 mixture Substances 0.000 claims description 6
- WZCQRUWWHSTZEM-UHFFFAOYSA-N 1,3-phenylenediamine Chemical compound NC1=CC=CC(N)=C1 WZCQRUWWHSTZEM-UHFFFAOYSA-N 0.000 claims description 5
- GELKBWJHTRAYNV-UHFFFAOYSA-K lithium iron phosphate Chemical compound [Li+].[Fe+2].[O-]P([O-])([O-])=O GELKBWJHTRAYNV-UHFFFAOYSA-K 0.000 claims description 5
- IAZDPXIOMUYVGZ-UHFFFAOYSA-N Dimethylsulphoxide Chemical compound CS(C)=O IAZDPXIOMUYVGZ-UHFFFAOYSA-N 0.000 claims description 4
- 229910000572 Lithium Nickel Cobalt Manganese Oxide (NCM) Inorganic materials 0.000 claims description 4
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 claims description 4
- FBDMTTNVIIVBKI-UHFFFAOYSA-N [O-2].[Mn+2].[Co+2].[Ni+2].[Li+] Chemical compound [O-2].[Mn+2].[Co+2].[Ni+2].[Li+] FBDMTTNVIIVBKI-UHFFFAOYSA-N 0.000 claims description 4
- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 claims description 3
- 229910052744 lithium Inorganic materials 0.000 claims description 3
- FXHOOIRPVKKKFG-UHFFFAOYSA-N N,N-Dimethylacetamide Chemical compound CN(C)C(C)=O FXHOOIRPVKKKFG-UHFFFAOYSA-N 0.000 claims description 2
- ZMXDDKWLCZADIW-UHFFFAOYSA-N N,N-Dimethylformamide Chemical compound CN(C)C=O ZMXDDKWLCZADIW-UHFFFAOYSA-N 0.000 claims description 2
- 229920000491 Polyphenylsulfone Polymers 0.000 claims description 2
- DVATZODUVBMYHN-UHFFFAOYSA-K lithium;iron(2+);manganese(2+);phosphate Chemical compound [Li+].[Mn+2].[Fe+2].[O-]P([O-])([O-])=O DVATZODUVBMYHN-UHFFFAOYSA-K 0.000 claims description 2
- 229910052759 nickel Inorganic materials 0.000 claims description 2
- MHSKRLJMQQNJNC-UHFFFAOYSA-N terephthalamide Chemical compound NC(=O)C1=CC=C(C(N)=O)C=C1 MHSKRLJMQQNJNC-UHFFFAOYSA-N 0.000 claims description 2
- DQWPFSLDHJDLRL-UHFFFAOYSA-N triethyl phosphate Chemical compound CCOP(=O)(OCC)OCC DQWPFSLDHJDLRL-UHFFFAOYSA-N 0.000 claims description 2
- 239000010405 anode material Substances 0.000 abstract description 8
- 239000011148 porous material Substances 0.000 abstract description 7
- 238000004519 manufacturing process Methods 0.000 abstract description 5
- 230000010287 polarization Effects 0.000 abstract description 4
- 238000010521 absorption reaction Methods 0.000 abstract description 3
- 239000007788 liquid Substances 0.000 abstract description 3
- 239000002253 acid Substances 0.000 abstract description 2
- 230000002708 enhancing effect Effects 0.000 abstract 1
- 230000001590 oxidative effect Effects 0.000 abstract 1
- 230000000052 comparative effect Effects 0.000 description 7
- 210000004379 membrane Anatomy 0.000 description 7
- 238000001291 vacuum drying Methods 0.000 description 7
- 239000003795 chemical substances by application Substances 0.000 description 6
- 239000000463 material Substances 0.000 description 6
- 238000005520 cutting process Methods 0.000 description 5
- 238000007789 sealing Methods 0.000 description 5
- WRDNCFQZLUCIRH-UHFFFAOYSA-N 4-(7-azabicyclo[2.2.1]hepta-1,3,5-triene-7-carbonyl)benzamide Chemical compound C1=CC(C(=O)N)=CC=C1C(=O)N1C2=CC=C1C=C2 WRDNCFQZLUCIRH-UHFFFAOYSA-N 0.000 description 3
- 238000003889 chemical engineering Methods 0.000 description 3
- 239000012847 fine chemical Substances 0.000 description 3
- 230000003647 oxidation Effects 0.000 description 3
- 238000007254 oxidation reaction Methods 0.000 description 3
- 210000002469 basement membrane Anatomy 0.000 description 2
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- 238000011161 development Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 150000002500 ions Chemical class 0.000 description 2
- 239000002245 particle Substances 0.000 description 2
- 229920000642 polymer Polymers 0.000 description 2
- 239000007787 solid Substances 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 241000732800 Cymbidium Species 0.000 description 1
- HFCVPDYCRZVZDF-UHFFFAOYSA-N [Li+].[Co+2].[Ni+2].[O-][Mn]([O-])(=O)=O Chemical compound [Li+].[Co+2].[Ni+2].[O-][Mn]([O-])(=O)=O HFCVPDYCRZVZDF-UHFFFAOYSA-N 0.000 description 1
- 239000011230 binding agent Substances 0.000 description 1
- 239000003153 chemical reaction reagent Substances 0.000 description 1
- 229940079593 drug Drugs 0.000 description 1
- 239000003814 drug Substances 0.000 description 1
- 239000003792 electrolyte Substances 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000002349 favourable effect Effects 0.000 description 1
- 229940125753 fibrate Drugs 0.000 description 1
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 description 1
- 229910052737 gold Inorganic materials 0.000 description 1
- 239000010931 gold Substances 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 229920000889 poly(m-phenylene isophthalamide) Polymers 0.000 description 1
- 229920003366 poly(p-phenylene terephthalamide) Polymers 0.000 description 1
- MWWATHDPGQKSAR-UHFFFAOYSA-N propyne Chemical compound CC#C MWWATHDPGQKSAR-UHFFFAOYSA-N 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
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Abstract
The invention discloses a lithium ion battery diaphragm with high heat exchange stability and a preparation method thereof, wherein the lithium ion battery diaphragm is formed by coating functional coating diaphragm slurry, and the preparation method of the functional coating diaphragm slurry comprises the following steps: the preparation method comprises the steps of firstly oxidizing a polyethylene microporous membrane by strong acid to ensure the uniformity and wettability of the pore diameter of the polyethylene microporous membrane, reducing the polarization in the battery to different degrees and enhancing the stability of the interior; manufacturing functional coating diaphragm slurry; the cross structure of the polyamide and the oily PVDF ensures the structural strength and the heat resistance of the lithium ion battery diaphragm; meanwhile, due to the introduction of the anode material, the contact interface between the anode material and the lithium ion battery diaphragm is improved, the liquid absorption rate and the conductivity of the lithium ion battery diaphragm are improved, and the internal impedance of the battery is reduced.
Description
Technical Field
The invention belongs to the technical field of battery diaphragms, and particularly relates to a lithium ion battery diaphragm with high heat exchange stability and a preparation method thereof.
Background
Nowadays, the new energy industry is rapidly developed, the improvement of the rapid charging capability becomes a common development target of battery manufacturers and whole vehicle factories, but with the development of technology, various potential safety hazards are gradually shown.
When the battery is continuously and rapidly charged, the ion concentration at the electrode is increased, the polarization is intensified, the terminal voltage of the battery cannot directly and linearly correspond to the charged electric quantity/energy, simultaneously, the high-current charging is carried out, the Joule heating effect is intensified due to the increase of the internal resistance, the danger coefficient is suddenly increased, the safety characteristic of the battery material is seriously tested, and meanwhile, the structural strength and the heat-resistant stability of the material are more and more important on the premise of ensuring good ion conductivity.
The lithium ion battery diaphragm is one of main battery materials, is a good insulating medium for isolating a positive electrode and a negative electrode, and the performance of the lithium ion battery diaphragm directly influences various performances of the lithium ion battery, so that the research on the functional coating diaphragm which can solve the problems in a matching manner is an urgent problem to be solved.
Disclosure of Invention
Aiming at the defects of the prior art, the invention aims to provide a preparation method of functional coating diaphragm slurry.
Another object of the present invention is to provide a functional coating separator slurry obtained by the above preparation method.
Based on the functional coating diaphragm slurry, the invention also aims to provide a method for preparing the lithium ion battery diaphragm with high heat exchange stability.
Another object of the present invention is to provide a lithium ion battery separator obtained by the above method.
The lithium ion battery diaphragm obtained by the method relatively reduces polarization inside the battery and enhances the stability inside the battery; the defects of the material in structural strength and heat resistance are overcome; the internal impedance of the battery is reduced, and the joule heat is reduced to different degrees.
The purpose of the invention is realized by the following technical scheme.
A preparation method of functional coating diaphragm slurry comprises the following steps:
uniformly mixing an organic solvent, oily PVDF, polyamide and a positive electrode material to obtain the functional coating diaphragm slurry, wherein the organic solvent is a mixture of one or more of N-methylpyrrolidone, N-dimethylacetamide, N-dimethylformamide, dimethyl sulfoxide and triethyl phosphate, the polyamide is a mixture of one or more of polyparaphenylene terephthalamide, polyisophthaloyl metaphenylene diamine, polyparaphenylene formamide and polyphenylsulfone terephthalamide, the positive electrode material is a lithium iron manganese phosphate, lithium iron phosphate, lithium cobaltate, lithium manganate, lithium nickel cobalt manganese oxide or high nickel ternary positive electrode material, and the ratio of the organic solvent, the oily PVDF and the polyamide is (13-23): (2-3.5): (1.5-2), and the positive electrode material is 0.3-0.5 wt% of the sum of the organic solvent, the oily PVDF and the polyamide.
In the technical scheme, the organic solvent, the oily PVDF and the polyamide are uniformly mixed, and then the anode material is added and uniformly mixed.
In the technical scheme, the organic solvent, the oily PVDF and the polyamide are uniformly mixed at the stirring speed of 1500-2200 rpm for 40-60 min.
In the technical scheme, the anode material is added and then stirred, the stirring time is 35-50 min, and the stirring speed is 1100-1500 rpm.
The functional coating diaphragm slurry obtained by the preparation method is provided.
A method for preparing a lithium ion battery separator with high heat exchange stability, comprising the following steps:
step 1, soaking a polyethylene microporous membrane in nitric acid at the temperature of 20-30 ℃ for 36-48 h, washing to be neutral, and drying to obtain a pre-treated base membrane;
in the step 1, washing is sequentially washing to be neutral by deionized water and ethanol.
In the step 1, the drying is carried out by airing at room temperature of 20-25 ℃ and then placing at 30-50 ℃ for 15-25 h.
In the step 1, the concentration of the nitric acid is 50-65 wt%.
And 2, coating the functional coating diaphragm slurry on one side of the pretreatment base film, extracting and drying to obtain the lithium ion battery diaphragm.
In the step 2, the drying temperature is 55-70 ℃, and the drying time is 15-25 min.
In the step 2, the extractant used for extraction is 3-methyl-1-butanol.
In the step 2, the extraction time is 15-35 min.
In the step 2, the coating speed is 20-30 m/min.
In the step 2, the coating is gravure coating.
In the step 2, the extraction is carried out at room temperature of 20-25 ℃.
In the step 2, the thickness of the coating formed by coating is 2.0-3.0 μm.
According to the invention, the polyethylene microporous membrane is oxidized by strong acid, so that the uniformity and wettability of the pore diameter of the polyethylene microporous membrane are ensured, the polarization in the battery is reduced to different degrees, and the stability in the battery is enhanced; then, manufacturing functional coating diaphragm slurry; the cross structure of the polyamide and the oily PVDF ensures the structural strength and the heat resistance of the lithium ion battery diaphragm; meanwhile, due to the introduction of the anode material, the contact interface between the anode and the lithium ion battery diaphragm is improved, the liquid absorption rate and the conductivity of the lithium ion battery diaphragm are improved, the internal impedance of the battery is reduced, the free movement of part of polymer chains is limited by the anode material particles, and the structural strength of the lithium ion battery diaphragm is further improved. The preparation of the functional coating diaphragm meets the use requirements of the existing quick-charging lithium ion battery.
Drawings
FIG. 1 is an SEM (20K times) of the polyethylene microporous membrane of example 1;
FIG. 2 is an SEM (20K magnification) of the pre-treated base film in example 1.
Detailed Description
The technical scheme of the invention is further explained by combining specific examples.
The relevant instrumentation used in the specific embodiment of the invention is as follows:
the stirrer: TYEE TXJ-60 model mixer;
electronic scale: shanghai Qifeng electronic ACS-DII type stirrer;
a water bath device: a DZ-75L type water bath device of Jiangsu cymbidium;
and (3) vacuum drying oven: a propine DZF type vacuum drying oven;
coating machine: an electromechanical CHTB-03 type coating machine is originally created.
The relevant drugs used in the embodiments of the present invention are as follows:
the polyethylene microporous membrane has a thickness of 12um and has a Kingchi effect;
n-methyl pyrrolidone, Nanjing Ruiz, with a purity of not less than 99.8%;
oily PVDF, Ningbo exhibition new material, coating level;
poly-p-phenylene terephthalamide, fine chemical engineering without tin bridge, fine grade;
lithium iron phosphate, Shenzhen fibrate, fine grade;
nitric acid, gold sea chemical, reagent grade;
ethanol, technical grade, bangzhou zhuoya chemical;
3-methyl-1-butanol, oriental Nanjing, fine grade;
poly (m-phenylene isophthalamide) and has no stannic bridge fine chemical engineering and fine grade;
lithium manganate, Tianjin union solid benefit, fine grade;
poly-p-benzamide, fine chemical engineering without a tin bridge, and fine grade;
lithium nickel cobalt manganese oxide, Tianjin union solid benefit, fine grade.
Example 1
A preparation method of functional coating diaphragm slurry comprises the following steps:
in a stirring tank, mixing N-methyl pyrrolidone, oily PVDF and poly-p-phenylene terephthalamide, stirring at 1600rpm for 40min to be uniform, adding lithium iron phosphate, stirring at 1100rpm for 35min, and uniformly mixing to obtain functional coating diaphragm slurry, wherein the ratio of the N-methyl pyrrolidone to the oily PVDF to the poly-p-phenylene terephthalamide is 16: 2: 1.5, the lithium iron phosphate accounts for 0.3 wt% of the sum of the mass of the N-methylpyrrolidone, the oily PVDF and the poly (p-phenylene terephthalamide).
A method for preparing a lithium ion battery separator with high heat exchange stability, comprising the following steps:
step 1, soaking a polyethylene microporous membrane in nitric acid for 36 hours (sealing) in a water bath environment at 25 ℃, sequentially washing the polyethylene microporous membrane to be neutral by using deionized water and ethanol, drying the polyethylene microporous membrane at the room temperature of 20-25 ℃, cutting edges to prevent edge curling, and placing the polyethylene microporous membrane in a vacuum drying oven at 35 ℃ for 15 hours to obtain a pretreatment base membrane, wherein the concentration of the nitric acid is 50 wt%;
and 2, coating the functional coating diaphragm slurry on one side of the pretreatment base film in a gravure coating mode, extracting for 20min at the room temperature of 20-25 ℃ by using 3-methyl-1-butanol as an extracting agent, and drying for 15min at the temperature of 55 ℃ to obtain the lithium ion battery diaphragm, wherein the coating speed is 25m/min, and the thickness of the coating formed by coating is 2.5 microns.
Example 2
A preparation method of functional coating diaphragm slurry comprises the following steps:
in a stirring tank, mixing N-methylpyrrolidone, oily PVDF and polyisophthaloyl metaphenylene diamine, stirring at the speed of 1800rpm for 50min until the mixture is uniform, adding lithium manganate, stirring at the stirring speed of 1300rpm for 40min, and uniformly mixing to obtain functional coating diaphragm slurry, wherein the ratio of the N-methylpyrrolidone to the oily PVDF to the polyisophthaloyl metaphenylene diamine is 20: 2.5: 1.8, the lithium manganate accounts for 0.3 wt% of the sum of the mass of the N-methylpyrrolidone, the mass of the oily PVDF and the mass of the polyisophthaloyl metaphenylene diamine.
A method for preparing a lithium ion battery separator with high heat exchange stability, comprising the following steps:
step 1, soaking a polyethylene microporous membrane in nitric acid for 40 hours (sealing) in a water bath environment at 25 ℃, sequentially washing the polyethylene microporous membrane to be neutral by using deionized water and ethanol, drying the polyethylene microporous membrane at the room temperature of 20-25 ℃, cutting edges, and standing the polyethylene microporous membrane in a vacuum drying oven at 40 ℃ for 18 hours to obtain a pretreated base membrane, wherein the concentration of the nitric acid is 55 wt%;
and 2, coating the functional coating diaphragm slurry on one side of the pretreatment base film in a gravure coating mode, extracting for 20min at the room temperature of 20-25 ℃ by using 3-methyl-1-butanol as an extracting agent, and drying for 18min at the temperature of 60 ℃ to obtain the lithium ion battery diaphragm, wherein the coating speed is 25m/min, and the thickness of a coating formed by coating is 2.5 microns.
Example 3
A preparation method of functional coating diaphragm slurry comprises the following steps:
in a stirring tank, mixing N-methyl pyrrolidone, oily PVDF and poly-p-benzamide, stirring at 2000rpm for 60min to be uniform, adding nickel-cobalt lithium manganate, stirring at 1500rpm for 45min, and mixing uniformly to obtain functional coating diaphragm slurry, wherein the ratio of N-methyl pyrrolidone, oily PVDF and poly-p-benzamide is 23: 3: 2, the lithium nickel cobalt manganese oxide accounts for 0.3 wt% of the sum of the mass of the N-methyl pyrrolidone, the mass of the oily PVDF and the mass of the poly-p-benzamide.
A method for preparing a lithium ion battery separator with high heat exchange stability, comprising the following steps:
step 1, soaking a polyethylene microporous membrane in nitric acid for 42 hours (sealing) in a water bath environment at 25 ℃, sequentially washing the polyethylene microporous membrane to be neutral by using deionized water and ethanol, drying the polyethylene microporous membrane at the room temperature of 20-25 ℃, cutting edges, and standing the polyethylene microporous membrane in a vacuum drying oven at the temperature of 50 ℃ for 20 hours to obtain a pre-treated basement membrane, wherein the concentration of the nitric acid is 60 wt%;
and 2, coating the functional coating diaphragm slurry on one side of the pretreatment base film in a gravure coating mode, extracting for 20min at the room temperature of 20-25 ℃ by using 3-methyl-1-butanol as an extracting agent, and drying for 20min at the temperature of 65 ℃ to obtain the lithium ion battery diaphragm, wherein the coating speed is 25m/min, and the thickness of the coating formed by coating is 2.5 microns.
Comparative example 1
A method of making a lithium ion battery separator comprising the steps of:
the functional coating diaphragm slurry in the embodiment 1 is coated on one side of a polyethylene microporous membrane in a gravure coating mode, 3-methyl-1-butanol is used as an extracting agent for extraction for 20min at the room temperature of 20-25 ℃, and the lithium ion battery diaphragm is obtained by drying for 15min at the temperature of 55 ℃, wherein the coating speed is 25m/min, and the thickness of a coating formed by coating is 2.5 mu m.
Comparative example 2
A method of preparing a slurry comprising the steps of:
in a stirring tank, mixing N-methyl pyrrolidone and oily PVDF, stirring at 1800rpm for 50min until uniform, adding lithium manganate, stirring at 1300rpm for 40min, and uniformly mixing to obtain slurry, wherein the ratio of N-methyl pyrrolidone to oily PVDF is 20: 2.5, the lithium manganate accounts for 0.3 wt% of the sum of the mass of the N-methyl pyrrolidone and the mass of the oily PVDF.
A method of making a lithium ion battery separator comprising the steps of:
step 1, soaking a polyethylene microporous membrane in nitric acid for 40 hours (sealing) in a water bath environment at 25 ℃, sequentially washing the polyethylene microporous membrane to be neutral by using deionized water and ethanol, drying the polyethylene microporous membrane at the room temperature of 20-25 ℃, cutting edges, and standing the polyethylene microporous membrane in a vacuum drying oven at 40 ℃ for 18 hours to obtain a pretreated base membrane, wherein the concentration of the nitric acid is 55 wt%;
and 2, coating the slurry on one side of the pre-treated base film in a gravure coating mode, extracting for 20min at the room temperature of 20-25 ℃ by using 3-methyl-1-butanol as an extracting agent, and drying for 18min at the temperature of 60 ℃ to obtain the lithium ion battery diaphragm, wherein the coating speed is 25m/min, and the thickness of a coating formed by coating is 2.5 mu m.
Comparative example 3
A method of preparing a slurry comprising the steps of:
mixing N-methylpyrrolidone, oily PVDF and poly-p-benzamide in a stirring tank, and stirring at 2000rpm for 60min until the mixture is uniform to obtain slurry, wherein the ratio of the N-methylpyrrolidone to the oily PVDF to the poly-p-benzamide is 23: 3: 2.
a method of making a lithium ion battery separator comprising the steps of:
step 1, soaking a polyethylene microporous membrane in nitric acid for 42 hours (sealing) in a water bath environment at 25 ℃, sequentially washing the polyethylene microporous membrane to be neutral by using deionized water and ethanol, drying the polyethylene microporous membrane at the room temperature of 20-25 ℃, cutting edges, and standing the polyethylene microporous membrane in a vacuum drying oven at the temperature of 50 ℃ for 20 hours to obtain a pre-treated basement membrane, wherein the concentration of the nitric acid is 60 wt%;
and 2, coating the slurry on one side of the pre-treated base film in a gravure coating mode, extracting for 20min at the room temperature of 20-25 ℃ by using 3-methyl-1-butanol as an extracting agent, and drying for 20min at the temperature of 65 ℃ to obtain the lithium ion battery diaphragm, wherein the coating speed is 25m/min, and the thickness of a coating formed by coating is 2.5 mu m.
The lithium ion battery separators obtained in examples 1 to 3 and comparative examples 1 to 3 were tested, and the test results are shown in table 1.
TABLE 1
As can be seen from the data in Table 1, the comparison between example 1 and comparative example 1 proves that the oxidation of the polyethylene microporous membrane greatly enhances the conductivity of the material; comparing the example 2 with the comparative example 2, the cross structure of the polyamide and the binder (oily PVDF) is proved to ensure the structural strength and the heat resistance of the lithium ion battery diaphragm; compared with the comparative example 3, the embodiment 3 further proves that the introduction of the anode material improves the contact interface of the anode and the lithium ion battery diaphragm, and improves the conductivity of the lithium ion battery diaphragm, thereby reducing the internal impedance of the battery, improving the liquid absorption rate of the lithium ion battery diaphragm, and meanwhile, the anode material particles limit the free movement of part of polymer chains to further improve the structural strength of the diaphragm, and enhance the stability of the lithium battery.
As can be seen from FIGS. 1 and 2, the pore size of the microporous polyethylene membrane is not uniform and has a slight closed pore phenomenon before oxidation, the pore size and shape of the pretreated base membrane are uniform after oxidation, the uniformity and stability of the pores are more favorable for the attachment of electrolyte, and the uniformity and wettability of the pore size of the base membrane are ensured.
The invention has been described in an illustrative manner, and it is to be understood that any simple variations, modifications or other equivalent changes which can be made by one skilled in the art without departing from the spirit of the invention fall within the scope of the invention.
Claims (10)
1. A preparation method of functional coating diaphragm slurry is characterized by comprising the following steps:
uniformly mixing an organic solvent, oily PVDF, polyamide and a positive electrode material to obtain the functional coating diaphragm slurry, wherein the organic solvent is a mixture of one or more of N-methylpyrrolidone, N-dimethylacetamide, N-dimethylformamide, dimethyl sulfoxide and triethyl phosphate, the polyamide is a mixture of one or more of polyparaphenylene terephthalamide, polyisophthaloyl metaphenylene diamine, polyparaphenylene formamide and polyphenylsulfone terephthalamide, the positive electrode material is a lithium iron manganese phosphate, lithium iron phosphate, lithium cobaltate, lithium manganate, lithium nickel cobalt manganese oxide or high nickel ternary positive electrode material, and the ratio of the organic solvent, the oily PVDF and the polyamide is (13-23): (2-3.5): (1.5-2), and the positive electrode material is 0.3-0.5 wt% of the sum of the organic solvent, the oily PVDF and the polyamide.
2. The preparation method according to claim 1, wherein the organic solvent, the oily PVDF and the polyamide are uniformly mixed, and then the positive electrode material is added and uniformly mixed.
3. The preparation method according to claim 2, wherein the organic solvent, the oily PVDF and the polyamide are uniformly mixed at a stirring speed of 1500-2200 rpm for 40-60 min.
4. The method according to claim 3, wherein the positive electrode material is added and then stirred at a stirring speed of 1100 to 1500rpm for 35 to 50 min.
5. The functional coating separator slurry obtained by the preparation method according to any one of claims 1 to 4.
6. A method for preparing a lithium ion battery diaphragm with high heat exchange stability is characterized by comprising the following steps:
step 1, soaking a polyethylene microporous membrane in nitric acid at the temperature of 20-30 ℃ for 36-48 h, washing to be neutral, and drying to obtain a pre-treated base membrane;
and 2, coating the functional coating diaphragm slurry of claim 5 on one side of the pre-treated base film, extracting and drying to obtain the lithium ion battery diaphragm.
7. The method according to claim 6, wherein in the step 1, the washing is sequentially washing with deionized water and ethanol to neutrality;
in the step 1, the drying is carried out by airing at room temperature of 20-25 ℃ and then placing for 15-25 h at 30-50 ℃;
in the step 1, the concentration of the nitric acid is 50-65 wt%.
8. The method of claim 6, wherein in the step 2, the drying temperature is 55-70 ℃ and the drying time is 15-25 min.
9. The method of claim 6, wherein in the step 2, the extractant used for extraction is 3-methyl-1-butanol;
in the step 2, the extraction time is 15-35 min;
in the step 2, the extraction is carried out at room temperature of 20-25 ℃.
10. The method according to claim 6, wherein in the step 2, the coating speed is 20-30 m/min;
in the step 2, the coating is gravure coating;
in the step 2, the thickness of the coating formed by coating is 2.0-3.0 μm.
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2012033438A (en) * | 2010-08-03 | 2012-02-16 | Hitachi Vehicle Energy Ltd | Cathode for lithium ion secondary battery and lithium ion secondary battery using the same |
| CN107706338A (en) * | 2017-11-24 | 2018-02-16 | 深圳锂硫科技有限公司 | A kind of lithium ion battery separator containing positive electrode and preparation method thereof |
| CN109301134A (en) * | 2018-10-31 | 2019-02-01 | 河北金力新能源科技股份有限公司 | Diaphragm coating paste and preparation method thereof, lithium ion battery separator and preparation method thereof and lithium ion battery |
| US20190225792A1 (en) * | 2016-06-28 | 2019-07-25 | Guangzhou Institute Of Energy Conversion, Chinese Academy Of Sciences | Multi-functionally Modified Polymer Binder for Lithium Ion Batteries and Use Thereof in Electrochemical Energy Storage Devices |
| CN113178658A (en) * | 2021-03-23 | 2021-07-27 | 河北金力新能源科技股份有限公司 | Lithium battery diaphragm slurry, high liquid absorption rate diaphragm and preparation method and application thereof |
| CN113659280A (en) * | 2021-07-13 | 2021-11-16 | 河北金力新能源科技股份有限公司 | Composite coating diaphragm with high conductivity, preparation method thereof and lithium battery formed by assembling composite coating diaphragm |
-
2021
- 2021-12-06 CN CN202111481063.XA patent/CN114335883A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2012033438A (en) * | 2010-08-03 | 2012-02-16 | Hitachi Vehicle Energy Ltd | Cathode for lithium ion secondary battery and lithium ion secondary battery using the same |
| US20190225792A1 (en) * | 2016-06-28 | 2019-07-25 | Guangzhou Institute Of Energy Conversion, Chinese Academy Of Sciences | Multi-functionally Modified Polymer Binder for Lithium Ion Batteries and Use Thereof in Electrochemical Energy Storage Devices |
| CN107706338A (en) * | 2017-11-24 | 2018-02-16 | 深圳锂硫科技有限公司 | A kind of lithium ion battery separator containing positive electrode and preparation method thereof |
| CN109301134A (en) * | 2018-10-31 | 2019-02-01 | 河北金力新能源科技股份有限公司 | Diaphragm coating paste and preparation method thereof, lithium ion battery separator and preparation method thereof and lithium ion battery |
| CN113178658A (en) * | 2021-03-23 | 2021-07-27 | 河北金力新能源科技股份有限公司 | Lithium battery diaphragm slurry, high liquid absorption rate diaphragm and preparation method and application thereof |
| CN113659280A (en) * | 2021-07-13 | 2021-11-16 | 河北金力新能源科技股份有限公司 | Composite coating diaphragm with high conductivity, preparation method thereof and lithium battery formed by assembling composite coating diaphragm |
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