CN113991240A - Surface high-strength high-heat-resistance corrosion-resistance modified lithium battery diaphragm and preparation method thereof - Google Patents
Surface high-strength high-heat-resistance corrosion-resistance modified lithium battery diaphragm and preparation method thereof Download PDFInfo
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- CN113991240A CN113991240A CN202111266370.6A CN202111266370A CN113991240A CN 113991240 A CN113991240 A CN 113991240A CN 202111266370 A CN202111266370 A CN 202111266370A CN 113991240 A CN113991240 A CN 113991240A
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- Prior art keywords
- preparation
- dispersing agent
- lithium battery
- coating
- battery diaphragm
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- 238000002360 preparation method Methods 0.000 title claims abstract description 18
- 150000002641 lithium Chemical class 0.000 title abstract description 4
- PLDDOISOJJCEMH-UHFFFAOYSA-N neodymium(3+);oxygen(2-) Chemical compound [O-2].[O-2].[O-2].[Nd+3].[Nd+3] PLDDOISOJJCEMH-UHFFFAOYSA-N 0.000 claims abstract description 34
- 238000003756 stirring Methods 0.000 claims abstract description 33
- 239000011248 coating agent Substances 0.000 claims abstract description 31
- 238000000576 coating method Methods 0.000 claims abstract description 31
- 239000002270 dispersing agent Substances 0.000 claims abstract description 25
- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 claims abstract description 20
- 239000000853 adhesive Substances 0.000 claims abstract description 20
- 230000001070 adhesive effect Effects 0.000 claims abstract description 20
- 229910052744 lithium Inorganic materials 0.000 claims abstract description 20
- 230000010355 oscillation Effects 0.000 claims abstract description 19
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 17
- 239000002002 slurry Substances 0.000 claims abstract description 14
- 238000001035 drying Methods 0.000 claims abstract description 11
- 238000002156 mixing Methods 0.000 claims abstract description 11
- 238000009210 therapy by ultrasound Methods 0.000 claims abstract description 7
- 229920000058 polyacrylate Polymers 0.000 claims description 10
- 230000007797 corrosion Effects 0.000 claims description 7
- 238000005260 corrosion Methods 0.000 claims description 7
- 238000000034 method Methods 0.000 claims description 7
- 150000003863 ammonium salts Chemical group 0.000 claims description 2
- 239000011247 coating layer Substances 0.000 claims 1
- 238000004519 manufacturing process Methods 0.000 claims 1
- QGZKDVFQNNGYKY-UHFFFAOYSA-O ammonium group Chemical group [NH4+] QGZKDVFQNNGYKY-UHFFFAOYSA-O 0.000 description 4
- HBBGRARXTFLTSG-UHFFFAOYSA-N Lithium ion Chemical compound [Li+] HBBGRARXTFLTSG-UHFFFAOYSA-N 0.000 description 2
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 2
- 230000000052 comparative effect Effects 0.000 description 2
- 229910001416 lithium ion Inorganic materials 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 230000007547 defect Effects 0.000 description 1
- 239000000463 material Substances 0.000 description 1
Images
Classifications
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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
- H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
- H01M50/40—Separators; Membranes; Diaphragms; Spacing elements inside cells
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
- H01M50/40—Separators; Membranes; Diaphragms; Spacing elements inside cells
- H01M50/403—Manufacturing processes of separators, membranes or diaphragms
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
- H01M50/40—Separators; Membranes; Diaphragms; Spacing elements inside cells
- H01M50/409—Separators, membranes or diaphragms characterised by the material
- H01M50/431—Inorganic material
-
- 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 discloses a surface high-strength high-heat-resistance corrosion-resistance modified lithium battery diaphragm and a preparation method thereof, wherein the preparation method comprises the following steps: the preparation method comprises the steps of uniformly mixing a dispersing agent, water and nano neodymium oxide, performing ultrasonic treatment, adding an adhesive, stirring and applying ultrasonic oscillation to obtain slurry, coating one or two surfaces of the slurry on a base film, obtaining a coating on the base film, and drying to obtain the lithium battery diaphragm.
Description
Technical Field
The invention belongs to the technical field of battery diaphragms, and particularly relates to a surface high-strength high-heat-resistance corrosion-resistance modified lithium battery diaphragm and a preparation method thereof.
Background
Along with the development demand of the country for new energy, electric vehicles based on lithium ion batteries have become a living part of people slowly, and along with the increase of the requirement of people for the energy density of the lithium ion batteries, the safety of the batteries has become a non-negligible part.
Based on the above, the battery safety of new energy automobiles has become the focus of much attention, the important decisive factors are the strength and the heat resistance of the battery diaphragm, the strength and the heat resistance of the conventional lithium battery diaphragm, which is a PP or PE diaphragm, are common, and the battery diaphragm needs to be subjected to surface modification to adapt to development requirements.
Disclosure of Invention
Aiming at the defects of the prior art, the invention aims to provide a preparation method of a lithium battery diaphragm with a modified surface with high strength, high heat resistance and corrosion resistance.
The purpose of the invention is realized by the following technical scheme.
A preparation method of a lithium battery diaphragm with a modified surface, high strength, high heat resistance and corrosion resistance comprises the following steps:
uniformly mixing a dispersing agent, water and nano neodymium oxide, performing ultrasonic treatment, adding an adhesive, stirring simultaneously, applying ultrasonic oscillation, and continuing for 20-30min to obtain a slurry, coating a single surface or double surfaces of the slurry on a base film to obtain a coating on the base film, and drying to obtain a lithium battery diaphragm, wherein the dispersing agent is an ammonium salt dispersing agent, the adhesive is polyacrylate, and the ratio of the dispersing agent to the water to the nano neodymium oxide to the adhesive is (0.1-0.5) in parts by mass: (71.5-84.9): (10-20): (5-8).
In the technical scheme, the method for uniformly mixing the dispersing agent, the water and the nano neodymium oxide comprises the following steps: mixing the dispersing agent, water and the nano neodymium oxide in a planetary stirring device for 10-20min, wherein the rotation speed of the planetary stirring device is 1500-3100r/min, and the revolution speed is 20-50 r/min.
In the technical scheme, the ultrasonic frequency is 10-50KHZ, and the ultrasonic time is 3-5 min.
In the technical scheme, the rotation speed of stirring and applying ultrasonic oscillation is 1000-3800r/min, the revolution speed is 20-40r/min, and the frequency of applying ultrasonic oscillation is 5-8 kHz.
In the above technical solution, the base film is a PE film.
In the technical scheme, the coating speed is 30-50 m/min.
In the technical scheme, the thickness of the coating is 2-5 μm.
In the technical scheme, the drying time is 1-3 min, and the drying temperature is 50-70 ℃.
The lithium battery diaphragm obtained by the preparation method.
According to the invention, the nano neodymium oxide with high strength and corrosion resistance is used as a modified material on the surface of the diaphragm, so that the heat resistance and puncture strength of the diaphragm can be effectively improved, the safety of the battery is improved, and the safety of an electric vehicle driven by a high-energy-density battery is further improved.
Drawings
Fig. 1 is an SEM of the lithium battery separator obtained in example 1;
fig. 2 is a photograph of the lithium battery separator obtained in example 1.
Detailed Description
The technical scheme of the invention is further explained by combining specific examples.
Nanometer neodymium oxide was purchased from october, beijing;
all coating machines are Dongshi 1350 type coating machines;
the planetary stirring equipment is of a Hodgte 30L type;
ultrasonic oscillation is performed by adopting ultrasonic oscillation equipment which is Kunshan adhesive KH2200 type;
example 1
A preparation method of a lithium battery diaphragm with a modified surface, high strength, high heat resistance and corrosion resistance comprises the following steps:
and blending the dispersing agent, water and the nano neodymium oxide in a planetary stirring device for 10min to obtain a first solution, wherein the rotation speed of the planetary stirring device is 3100r/min, and the revolution speed is 20 r/min.
And (3) carrying out ultrasonic treatment on the first solution at the frequency of 50KHZ for 3min, adding an adhesive, stirring simultaneously, applying ultrasonic oscillation, and continuing for 25min to obtain slurry, wherein the rotation speed of stirring in the stirring and ultrasonic oscillation applying process is 1000r/min, the revolution speed is 40r/min, and the ultrasonic oscillation applying frequency is 5 kHz.
Coating the single side of the slurry on a base film by adopting a coating machine, wherein the base film is a PE film with the thickness of 12 micrometers, a coating with the thickness of 5 micrometers is obtained on the base film, the coating is dragged by a traction roller to enter drying equipment, and is dried for 3min at 50 ℃ to obtain the lithium battery diaphragm, wherein a dispersing agent is ammonium polyacrylate, an adhesive is polyacrylate, and the ratio of the dispersing agent to water to nano neodymium oxide to the adhesive is 0.2: 79.8: 15: 5, the coating speed is 30 m/min.
Example 2
A preparation method of a lithium battery diaphragm with a modified surface, high strength, high heat resistance and corrosion resistance comprises the following steps:
and blending the dispersing agent, water and the nano neodymium oxide in a planetary stirring device for 15min to obtain a first solution, wherein the rotation speed of the planetary stirring device is 2000r/min, and the revolution speed of the planetary stirring device is 30 r/min.
And (3) carrying out ultrasonic treatment on the first solution at the frequency of 30KHZ for 4min, adding an adhesive, stirring while applying ultrasonic oscillation for 25min to obtain slurry, wherein the rotation speed of stirring during stirring and applying ultrasonic oscillation is 2800r/min, the revolution speed is 30r/min, and the frequency of applying ultrasonic oscillation is 6 kHz.
Coating the single side of the slurry on a base film by adopting a coating machine, wherein the base film is a PE film with the thickness of 12 micrometers, a coating with the thickness of 3 micrometers is obtained on the base film, the coating is dragged by a traction roller to enter drying equipment, and is dried for 2min at the temperature of 60 ℃ to obtain the lithium battery diaphragm, wherein the dispersing agent is ammonium polyacrylate, the adhesive is polyacrylate, and the ratio of the dispersing agent to water to the nano neodymium oxide to the adhesive is 0.3: 83.7: 10: 6, the coating speed was 40 m/min.
Example 3
A preparation method of a lithium battery diaphragm with a modified surface, high strength, high heat resistance and corrosion resistance comprises the following steps:
and blending the dispersing agent, water and the nano neodymium oxide in a planetary stirring device for 20min to obtain a first solution, wherein the rotation speed of the planetary stirring device is 1500r/min, and the revolution speed of the planetary stirring device is 50 r/min.
And (3) carrying out ultrasonic treatment on the first solution at the frequency of 50KHZ for 5min, adding an adhesive, stirring while applying ultrasonic oscillation for 25min to obtain slurry, wherein the rotation speed of stirring during stirring and applying ultrasonic oscillation is 3800r/min, the revolution speed of stirring is 20r/min, and the frequency of applying ultrasonic oscillation is 8 kHz.
Coating the single side of the slurry on a base film by adopting a coating machine, wherein the base film is a PE film with the thickness of 12 micrometers, a coating with the thickness of 2 micrometers is obtained on the base film, the coating is dragged by a traction roller to enter drying equipment, and is dried for 1min at 70 ℃ to obtain the lithium battery diaphragm, wherein a dispersing agent is ammonium polyacrylate, an adhesive is polyacrylate, and the ratio of the dispersing agent to water to nano neodymium oxide to the adhesive is 0.5: 71.5: 20: 8, the coating speed was 50 m/min.
Comparative example
A preparation method of a lithium battery diaphragm comprises the following steps:
and (3) blending the dispersing agent, water and nano-alumina in a planetary stirring device for 10min to obtain a first solution, wherein the rotation speed of the planetary stirring device is 3100r/min, and the revolution speed is 25 r/min.
And (3) carrying out ultrasonic treatment on the first solution at the frequency of 30KHZ for 5min, adding an adhesive, stirring simultaneously, applying ultrasonic oscillation, and continuing for 25min to obtain slurry, wherein the rotation speed of stirring in the stirring and ultrasonic oscillation applying process is 1800r/min, the revolution speed is 24r/min, and the ultrasonic oscillation applying frequency is 5 kHz.
Coating the single side of the slurry on a base film by adopting a coating machine, wherein the base film is a PE film with the thickness of 12 micrometers, a coating with the thickness of 2 micrometers is obtained on the base film, the coating is dragged by a traction roller to enter drying equipment, and is dried for 1min at 50 ℃ to obtain the lithium battery diaphragm, wherein a dispersing agent is ammonium polyacrylate, an adhesive is polyacrylate, and the ratio of the dispersing agent to water to nano aluminum oxide to the adhesive is 0.1: 64.9: 30: 5, the coating speed is 50 m/min.
The lithium battery separators obtained in examples 1-3 and comparative example were tested, and the test results are shown in table 1.
TABLE 1
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 (9)
1. The preparation method of the lithium battery diaphragm with the modified surface, high strength, high heat resistance and corrosion resistance is characterized by comprising the following steps:
uniformly mixing a dispersing agent, water and nano neodymium oxide, performing ultrasonic treatment, adding an adhesive, stirring simultaneously, applying ultrasonic oscillation, and continuing for 20-30min to obtain a slurry, coating a single surface or double surfaces of the slurry on a base film to obtain a coating on the base film, and drying to obtain a lithium battery diaphragm, wherein the dispersing agent is an ammonium salt dispersing agent, the adhesive is polyacrylate, and the ratio of the dispersing agent to the water to the nano neodymium oxide to the adhesive is (0.1-0.5) in parts by mass: (71.5-84.9): (10-20): (5-8).
2. The preparation method according to claim 1, wherein the method for uniformly mixing the dispersing agent, the water and the nano neodymium oxide comprises the following steps: mixing the dispersing agent, water and the nano neodymium oxide in a planetary stirring device for 10-20min, wherein the rotation speed of the planetary stirring device is 1500-3100r/min, and the revolution speed is 20-50 r/min.
3. The method according to claim 1, wherein the ultrasonic frequency is 10-50KHZ and the ultrasonic time is 3-5 min.
4. The preparation method according to claim 2 or 3, wherein the rotation speed of the simultaneous stirring and ultrasonic vibration application is 1000-3800r/min, the revolution speed is 20-40r/min, and the frequency of the ultrasonic vibration application is 5-8 kHz.
5. The production method according to claim 1, wherein the base film is a PE film.
6. The method of claim 1, wherein the coating speed is 30 to 50 m/min.
7. The method of claim 1, wherein the coating layer has a thickness of 2 to 5 μm.
8. The preparation method according to claim 1, wherein the drying time is 1-3 min, and the drying temperature is 50-70 ℃.
9. A lithium battery separator obtained by the preparation method according to any one of claims 1 to 8.
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| CN202111266370.6A CN113991240A (en) | 2021-10-28 | 2021-10-28 | Surface high-strength high-heat-resistance corrosion-resistance modified lithium battery diaphragm and preparation method thereof |
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| CN202111266370.6A CN113991240A (en) | 2021-10-28 | 2021-10-28 | Surface high-strength high-heat-resistance corrosion-resistance modified lithium battery diaphragm and preparation method thereof |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115395173A (en) * | 2022-08-18 | 2022-11-25 | 河北金力新能源科技股份有限公司 | High-heat-resistance high-insulation lithium battery diaphragm and preparation method thereof |
| CN115483500A (en) * | 2022-09-21 | 2022-12-16 | 河北金力新能源科技股份有限公司 | High-circulation-rate diaphragm and preparation method thereof |
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| JP2001250529A (en) * | 2000-03-03 | 2001-09-14 | Nippon Sheet Glass Co Ltd | Alkaline secondary battery |
| CN104269505A (en) * | 2014-10-27 | 2015-01-07 | 沧州明珠隔膜科技有限公司 | Composite lithium ion battery diaphragm and preparation method thereof |
| WO2018068745A1 (en) * | 2016-10-12 | 2018-04-19 | 河北金力新能源科技股份有限公司 | Method for preparing lithium ion battery separator with high temperature resistance and low electrical resistivity |
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| CN110197883A (en) * | 2019-05-09 | 2019-09-03 | 湖南文理学院 | A kind of lithium ion battery anodic aluminium oxide membrane and preparation method |
| CN111769239A (en) * | 2019-04-02 | 2020-10-13 | 河北金力新能源科技股份有限公司 | Heat-resistant high-strength composite lithium battery diaphragm and preparation method and application thereof |
-
2021
- 2021-10-28 CN CN202111266370.6A patent/CN113991240A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
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| JP2001250529A (en) * | 2000-03-03 | 2001-09-14 | Nippon Sheet Glass Co Ltd | Alkaline secondary battery |
| CN104269505A (en) * | 2014-10-27 | 2015-01-07 | 沧州明珠隔膜科技有限公司 | Composite lithium ion battery diaphragm and preparation method thereof |
| WO2018068745A1 (en) * | 2016-10-12 | 2018-04-19 | 河北金力新能源科技股份有限公司 | Method for preparing lithium ion battery separator with high temperature resistance and low electrical resistivity |
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| CN111769239A (en) * | 2019-04-02 | 2020-10-13 | 河北金力新能源科技股份有限公司 | Heat-resistant high-strength composite lithium battery diaphragm and preparation method and application thereof |
| CN110197883A (en) * | 2019-05-09 | 2019-09-03 | 湖南文理学院 | A kind of lithium ion battery anodic aluminium oxide membrane and preparation method |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115395173A (en) * | 2022-08-18 | 2022-11-25 | 河北金力新能源科技股份有限公司 | High-heat-resistance high-insulation lithium battery diaphragm and preparation method thereof |
| CN115483500A (en) * | 2022-09-21 | 2022-12-16 | 河北金力新能源科技股份有限公司 | High-circulation-rate diaphragm and preparation method thereof |
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Application publication date: 20220128 |