CN111682145A - Solid-state diaphragm slurry of lithium ion battery, preparation method and application - Google Patents
Solid-state diaphragm slurry of lithium ion battery, preparation method and application Download PDFInfo
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- CN111682145A CN111682145A CN202010513699.7A CN202010513699A CN111682145A CN 111682145 A CN111682145 A CN 111682145A CN 202010513699 A CN202010513699 A CN 202010513699A CN 111682145 A CN111682145 A CN 111682145A
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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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- 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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Abstract
The invention discloses a solid diaphragm slurry of a lithium ion battery, which comprises the following components in parts by mass: 100 parts of solvent, 92-97 parts of solid diaphragm active substance, 3-8 parts of adhesive, 2-4 parts of complexing agent and 2-4 parts of diluent. The invention also discloses a preparation method of the solid diaphragm of the lithium ion battery and the lithium ion battery containing the solid diaphragm prepared by the preparation method. The invention provides solid diaphragm slurry of a lithium ion battery, wherein scattering micropores in the diaphragm slurry have good liquid locking and impact resistance, and compared with the traditional PP + PE + PP three-layer composite diaphragm, no liquid free electrolyte exists in a battery core, so that the battery can be prevented from being ignited due to short circuit caused by physical impact and extrusion.
Description
Technical Field
The invention relates to the technical field of lithium ion battery manufacturing, in particular to solid diaphragm slurry of a lithium ion battery, a preparation method and application.
Background
The diaphragm adopted by the traditional lithium ion battery is a single-layer PP or PE or a composite of three layers of PP + PE + PP, and then is coated with a ceramic coating, the positive and negative pole pieces are laminated and welded with pole lugs, an aluminum-plastic film is punched to a corresponding depth according to the design requirement and then is loaded into a battery cell for top side sealing, and electrolyte is injected after high-temperature vacuum baking. Due to the existence of free electrolyte, when the battery module encounters a collision accident on an automobile, the battery module is very easy to cause short circuit and fire, and larger safety accidents are easy to happen.
Disclosure of Invention
Aiming at the problems, the invention aims to provide solid-state diaphragm slurry of a lithium ion battery with good liquid locking and impact resistance, a preparation method and application.
In order to achieve the purpose, the technical scheme adopted by the invention is as follows:
the solid-state diaphragm slurry for the lithium ion battery comprises the following components in parts by mass: 100 parts of solvent, 92-97 parts of solid diaphragm active substance, 3-8 parts of adhesive, 2-4 parts of complexing agent and 2-4 parts of diluent.
Further, the solvent is acetone solvent with the concentration of 50-70%.
Further, the solid diaphragm active material is crystalline SiO 2.
Further, the adhesive is PVDF or PVDF-HFP.
Further, the complexing agent is dimethylacetamide.
Further, the diluent is dibutyl phthalate.
The invention also discloses a preparation method of the solid diaphragm slurry of the lithium ion battery, which comprises the following steps:
s1, adding 3-8 parts of adhesive and 100 parts of solvent into a planetary stirrer to mix, wherein the stirring temperature is 35-41 ℃, and the stirring speed is as follows: revolving for 15-20 r/min, dispersing for 1500-2400 r/min, and stirring for 180-240 min in a forward rotation manner.
S2, adding 2-4 parts of diluent into the slurry prepared in the step S1, mixing and stirring at the stirring temperature of 30-50 ℃ at the stirring speed of: revolution is carried out for 15-20 r/min, dispersion is carried out for 1000-1500 r/min, and forward rotation stirring is carried out for 10-45 min.
S3, adding 2-4 parts of complexing agent into the slurry prepared in the step S2, mixing and stirring at the stirring temperature of 30-50 ℃ at the stirring speed of: revolution is carried out for 15-20 r/min, dispersion is carried out for 1000-1500 r/min, and forward rotation stirring is carried out for 10-45 min.
S4, adding 92-97 parts of solid diaphragm active substance into the slurry prepared in the step S3, mixing and stirring at the stirring temperature of 30-40 ℃ at the stirring speed of: revolution is carried out at 15-20 r/min, dispersion is carried out at 1800-2400 r/min, and forward rotation stirring is carried out for 60-180 min.
S5, cooling the wall of the stirring tank by cooling water, wherein the stirring temperature is 25-30 ℃, and the stirring speed is as follows: and revolving for 15-20 r/min, dispersing for 800-1300 r/min, and stirring in a forward rotation manner for 20-60 min to obtain the semitransparent high-viscosity lithium ion battery solid diaphragm slurry.
Preferably, in the step S4 and the step S5, the internal pressure of the device during stirring is-0.098 MPa to-0.095 MPa.
Further, the solvent is acetone, the active substance of the solid diaphragm is crystalline SiO2, the adhesive is PVDF or PVDF-HFP, the complexing agent is dimethylacetamide, and the diluent is dibutyl phthalate.
The invention also discloses the application of the lithium ion battery solid diaphragm slurry or the slurry prepared by the preparation method of the lithium ion battery solid diaphragm slurry in a lithium ion battery.
The invention has the following beneficial effects: the scattering micropores in the solid diaphragm slurry have good liquid locking and impact resistance, and compared with the traditional PP + PE + PP three-layer composite diaphragm, the scattering micropores in the solid diaphragm slurry have no liquid free electrolyte in the battery core, so that the battery can be prevented from being ignited due to short circuit caused by physical impact and extrusion, and the problems of battery core failure and the like caused by battery leakage and the like are greatly reduced. The solid diaphragm slurry has simple manufacturing process, and the battery adopting the solid diaphragm slurry has high performance and good safety performance.
Drawings
Fig. 1 is an SEM scanning electron micrograph of the solid separator slurry.
Detailed Description
The invention is further described with reference to the following drawings and detailed description.
Example one
The solid-state diaphragm slurry for the lithium ion battery comprises the following components in parts by mass: 100 parts of an acetone solvent with a concentration of 60%, 92 parts of high-crystallinity SiO2, 8 parts of PVDF, 4 parts of dimethylacetamide and 4 parts of dibutyl phthalate.
The preparation method of the solid-state diaphragm slurry of the lithium ion battery comprises the following steps:
step one, adding 8 parts of PVDF and 100 parts of acetone solvent with the concentration of 60% into a 30L double-planet stirrer to be mixed, wherein the stirring temperature is 40 ℃, and the stirring speed is as follows: revolving for 15r/min, dispersing for 1500r/min, and rotating forward and stirring for 180 min.
And secondly, adding 4 parts of dibutyl phthalate into the slurry prepared in the first step, mixing and stirring at the stirring temperature of 30-50 ℃, introducing cooling water to reduce the temperature at the temperature of over 50 ℃, and stirring at the speed of: revolving for 20r/min, dispersing for 1500r/min, and stirring in positive rotation for 30 min.
And step three, adding 4 parts of dimethylacetamide into the slurry prepared in the step two, mixing and stirring, wherein the stirring temperature is 30-50 ℃, cooling water is introduced for cooling when the temperature exceeds 50 ℃, and the stirring speed is as follows: revolving for 20r/min, dispersing for 1500r/min, and stirring in positive rotation for 45 min.
And step four, adding 92 parts of high-crystallinity SiO2 into the slurry prepared in the step three, mixing and stirring at the stirring temperature of 30-40 ℃, introducing cooling water to reduce the temperature above 40 ℃, and stirring at the speed of: revolving at 20r/min, dispersing at 1800r/min, stirring in forward rotation for 120min, and stirring at vacuum degree of-0.095 MPa.
And fifthly, introducing cooling water to the wall of the stirring tank to cool, wherein the stirring temperature is 25-30 ℃, and the stirring speed is as follows: revolution at 15r/min, dispersion at 800r/min, forward rotation stirring for 30min, and stirring vacuum degree of-0.095 Mpa to obtain the semitransparent high-viscosity lithium ion battery solid diaphragm slurry.
As shown in fig. 1, an SEM (scanning electron microscope) image of the solid-state separator slurry of the first embodiment shows that scattering through holes are distributed on the surface of the molded separator slurry.
Example two
The solid-state diaphragm slurry for the lithium ion battery comprises the following components in parts by mass: 100 parts of an acetone solvent with a concentration of 60%, 95 parts of high-crystallinity SiO2, 5 parts of PVDF, 3 parts of dimethylacetamide and 3 parts of dibutyl phthalate.
The preparation method of the solid-state diaphragm slurry of the lithium ion battery comprises the following steps:
step one, adding 5 parts of PVDF and 100 parts of acetone solvent with the concentration of 60% into a 30L double-planet stirrer for mixing, wherein the stirring temperature is 40 ℃, and the stirring speed is as follows: revolution at 18r/min, dispersion at 2000r/min, forward rotation and stirring for 220 min.
And secondly, adding 3 parts of dibutyl phthalate into the slurry prepared in the first step, mixing and stirring, wherein the stirring temperature is 30-50 ℃, and cooling is carried out by introducing cooling water at the temperature of over 50 ℃, and the stirring speed is as follows: revolution at 18r/min, dispersion at 1500r/min, forward rotation stirring for 40 min.
And step three, adding 3 parts of dimethylacetamide into the slurry prepared in the step two, mixing and stirring, wherein the stirring temperature is 30-50 ℃, cooling water is introduced for cooling when the temperature exceeds 50 ℃, and the stirring speed is as follows: revolution at 18r/min, dispersion at 1500r/min, forward rotation stirring for 40 min.
And step four, adding 95 parts of high-crystallinity SiO2 into the slurry prepared in the step three, mixing and stirring, wherein the stirring temperature is 30-40 ℃, the temperature is higher than 40 ℃, cooling water is introduced for cooling, and the stirring speed is as follows: revolution at 20r/min, dispersion at 2100r/min, forward rotation stirring for 150min, and stirring vacuum degree of-0.098 Mpa.
And fifthly, introducing cooling water to the wall of the stirring tank to cool, wherein the stirring temperature is 25-30 ℃, and the stirring speed is as follows: revolution at 18r/min, dispersion at 1100r/min, forward rotation stirring for 40min, and stirring vacuum degree of-0.098 Mpa to obtain the semitransparent high-viscosity lithium ion battery solid diaphragm slurry.
EXAMPLE III
The solid-state diaphragm slurry for the lithium ion battery comprises the following components in parts by mass: 100 parts of an acetone solvent with a concentration of 60%, 97 parts of high-crystallinity SiO2, 3 parts of PVDF, 2 parts of dimethylacetamide and 2 parts of dibutyl phthalate.
The preparation method of the solid-state diaphragm slurry of the lithium ion battery comprises the following steps:
step one, adding 3 parts of PVDF and 100 parts of acetone solvent with the concentration of 60% into a 30L double-planet stirrer for mixing, wherein the stirring temperature is 40 ℃, and the stirring speed is as follows: revolving for 20r/min, dispersing for 2400r/min, and stirring in forward rotation for 240 min.
And secondly, adding 2 parts of dibutyl phthalate into the slurry prepared in the first step, mixing and stirring at the stirring temperature of 30-50 ℃, introducing cooling water to reduce the temperature at the temperature of over 50 ℃, and stirring at the speed of: revolving for 15r/min, dispersing for 1500r/min, and stirring in positive rotation for 45 min.
And step three, adding 2 parts of dimethylacetamide into the slurry prepared in the step two, mixing and stirring, wherein the stirring temperature is 30-50 ℃, cooling water is introduced for cooling when the temperature exceeds 50 ℃, and the stirring speed is as follows: revolving for 15r/min, dispersing for 1500r/min, and stirring in positive rotation for 30 min.
And step four, adding 97 parts of high-crystallinity SiO2 into the slurry prepared in the step three, mixing and stirring, wherein the stirring temperature is 30-40 ℃, the temperature is higher than 40 ℃, cooling water is introduced for cooling, and the stirring speed is as follows: revolution at 20r/min, dispersion at 2400r/min, forward rotation stirring for 180min, and stirring vacuum degree of-0.095 Mpa.
And fifthly, introducing cooling water to the wall of the stirring tank to cool, wherein the stirring temperature is 25-30 ℃, and the stirring speed is as follows: revolution at 20r/min, dispersion at 1300r/min, forward rotation stirring for 45min, and stirring vacuum degree of-0.095 Mpa to obtain the semitransparent high-viscosity lithium ion battery solid diaphragm slurry.
The translucent high-viscosity lithium ion battery solid-state separator slurry prepared in the first, second and third examples were subjected to solid content, viscosity and fineness tests, and the results are shown in table 1.
| Item | Viscosity of the slurry mpa.s | Fineness of slurry um | Solid content of the slurry% | The slurry is kept stand for 48h, and the viscosity mpa.s is |
| Example one | 7000-11500 | 8-15 | 50-55 | 6500-10000 |
| Example two | 8000-12500 | 8-15 | 52-57 | 7200-11000 |
| EXAMPLE III | 9000-13500 | 8-15 | 53-58 | 8000-12000 |
Table 1: test table for solid content, viscosity and fineness of slurry
Solid separators made from the solid separator slurries obtained in the first, second and third examples were subjected to mechanical testing and compared with a conventional PP + PE + PP three-layer composite separator, and the results are shown in table 2.
Table 2: mechanical property test meter for solid diaphragm and traditional three-layer composite diaphragm
As can be seen from the test results in Table 2, the solid-state separator prepared from the slurry prepared by the invention has good mechanical properties and can have good impact resistance when applied to a lithium ion battery.
While the invention has been particularly shown and described with reference to a preferred embodiment, it will be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.
Claims (10)
1. The solid-state diaphragm slurry of the lithium ion battery is characterized by comprising the following components in parts by mass: 100 parts of solvent, 92-97 parts of solid diaphragm active substance, 3-8 parts of adhesive, 2-4 parts of complexing agent and 2-4 parts of diluent.
2. The lithium ion battery solid state separator paste of claim 1, wherein: the solvent is acetone solvent with the concentration of 50-70%.
3. The lithium ion battery solid state separator paste of claim 1, wherein: the solid diaphragm active substance is crystalline SiO 2.
4. The lithium ion battery solid state separator paste of claim 1, wherein: the adhesive is PVDF or PVDF-HFP.
5. The lithium ion battery solid state separator paste of claim 1, wherein: the complexing agent is dimethylacetamide.
6. The lithium ion battery solid state separator paste of claim 1, wherein: the diluent is dibutyl phthalate.
7. The preparation method of the solid-state diaphragm slurry of the lithium ion battery is characterized by comprising the following steps of:
s1, adding 3-8 parts of adhesive and 100 parts of solvent into a planetary stirrer to mix, wherein the stirring temperature is 35-41 ℃, and the stirring speed is as follows: revolving for 15-20 r/min, dispersing for 1500-2400 r/min, and stirring for 180-240 min in a forward rotation manner;
s2, adding 2-4 parts of diluent into the slurry prepared in the step S1, mixing and stirring at the stirring temperature of 30-50 ℃ at the stirring speed of: revolving for 15-20 r/min, dispersing for 1000-1500 r/min, and stirring for 10-45 min in a forward rotation manner;
s3, adding 2-4 parts of complexing agent into the slurry prepared in the step S2, mixing and stirring at the stirring temperature of 30-50 ℃ at the stirring speed of: revolving for 15-20 r/min, dispersing for 1000-1500 r/min, and stirring for 10-45 min in a forward rotation manner;
s4, adding 92-97 parts of solid diaphragm active substance into the slurry prepared in the step S3, mixing and stirring at the stirring temperature of 30-40 ℃ at the stirring speed of: revolving for 15-20 r/min, dispersing for 1800-2400 r/min, and stirring for 60-180 min in a forward rotation manner;
s5, cooling the wall of the stirring tank by cooling water, wherein the stirring temperature is 25-30 ℃, and the stirring speed is as follows: and revolving for 15-20 r/min, dispersing for 800-1300 r/min, and stirring in a forward rotation manner for 20-60 min to obtain the semitransparent high-viscosity lithium ion battery solid diaphragm slurry.
8. The preparation method of the lithium ion battery solid-state separator slurry according to claim 7, characterized by comprising the following steps: in the step S4 and the step S5, the internal pressure of the equipment during stirring is-0.098 MPa to-0.095 MPa.
9. The preparation method of the lithium ion battery solid-state separator slurry according to claim 7, characterized by comprising the following steps: the solvent is acetone, the solid diaphragm active substance is crystalline SiO2, the adhesive is PVDF or PVDF-HFP, the complexing agent is dimethylacetamide, and the diluent is dibutyl phthalate.
10. The lithium ion battery solid-state separator slurry according to any one of claims 1 to 6 or the lithium ion battery solid-state separator slurry according to any one of claims 7 to 9, wherein the slurry is applied to a lithium ion battery.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202010513699.7A CN111682145A (en) | 2020-06-08 | 2020-06-08 | Solid-state diaphragm slurry of lithium ion battery, preparation method and application |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202010513699.7A CN111682145A (en) | 2020-06-08 | 2020-06-08 | Solid-state diaphragm slurry of lithium ion battery, preparation method and application |
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2016169289A1 (en) * | 2015-04-20 | 2016-10-27 | 田东 | Method for preparing lithium ion battery negative electrode slurry |
| CN109524596A (en) * | 2018-11-20 | 2019-03-26 | 桑顿新能源科技有限公司 | A kind of diaphragm for lithium ion battery material and preparation method thereof |
| CN109860480A (en) * | 2018-12-29 | 2019-06-07 | 桑顿新能源科技有限公司 | A kind of gel state lithium ion battery diaphragm and preparation method thereof |
| CN111129393A (en) * | 2019-11-18 | 2020-05-08 | 高芳 | Mixed coating lithium battery diaphragm and preparation method thereof |
-
2020
- 2020-06-08 CN CN202010513699.7A patent/CN111682145A/en not_active Withdrawn
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2016169289A1 (en) * | 2015-04-20 | 2016-10-27 | 田东 | Method for preparing lithium ion battery negative electrode slurry |
| CN109524596A (en) * | 2018-11-20 | 2019-03-26 | 桑顿新能源科技有限公司 | A kind of diaphragm for lithium ion battery material and preparation method thereof |
| CN109860480A (en) * | 2018-12-29 | 2019-06-07 | 桑顿新能源科技有限公司 | A kind of gel state lithium ion battery diaphragm and preparation method thereof |
| CN111129393A (en) * | 2019-11-18 | 2020-05-08 | 高芳 | Mixed coating lithium battery diaphragm and preparation method thereof |
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Application publication date: 20200918 |