CN110970587A - Composite diaphragm for lithium-sulfur battery and preparation and application thereof - Google Patents
Composite diaphragm for lithium-sulfur battery and preparation and application thereof Download PDFInfo
- Publication number
- CN110970587A CN110970587A CN201811140113.6A CN201811140113A CN110970587A CN 110970587 A CN110970587 A CN 110970587A CN 201811140113 A CN201811140113 A CN 201811140113A CN 110970587 A CN110970587 A CN 110970587A
- Authority
- CN
- China
- Prior art keywords
- active monomer
- lithium
- water
- organic phase
- soluble active
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Images
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- 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
- H01M50/411—Organic material
-
- 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
- H01M50/449—Separators, membranes or diaphragms characterised by the material having a layered structure
-
- 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 composite diaphragm with an ultrathin coating, and a preparation method and application thereof. A layer of interface film is generated through the polymerization reaction of two monomers at an oil-water interface, and then the interface film is transferred to the porous polyolefin diaphragm to form the composite diaphragm. The invention can effectively control the thickness and the surface aperture of the interface film, and the formed composite diaphragm can effectively inhibit the shuttle flying effect of polysulfide and has higher mechanical strength; in addition, the method has the advantages of simple preparation process, less time consumption and low cost, and is favorable for further popularization and use.
Description
Technical Field
The invention relates to the field of lithium-sulfur batteries, in particular to a composite diaphragm and a preparation method and application thereof.
Background
In order to solve the energy crisis and the problem of environmental pollution caused by the combustion of fossil fuels, electric vehicles are receiving more and more extensive attention. Lithium ion batteries which use lithium iron phosphate and ternary materials as anodes are widely used in electric automobiles at present, and the theoretical specific capacity of the lithium ion batteries is 300mAh/g due to the limitation of material properties, so that the requirements of long-mileage electric automobiles cannot be met. The theoretical specific capacity of the lithium-sulfur battery is 5 times of that of the commercial lithium ion battery (the theoretical specific capacity is 1672mAh/g, and the specific energy is 2600 Wh/kg). Is considered to be one of the most potential high energy batteries.
The true commercialization of lithium sulfur batteries still faces a number of challenges, mainly the presence of the "shuttle effect" of polysulfides. The separators currently used in lithium-sulfur batteries are mainly polyolefins, Polyethylene (PE), polypropylene (PP) and composites of the two. The pore diameter of the polyolefin diaphragm is 50-350nm and is far larger than the size of polysulfide, and during the charging process of the battery, polysulfide is oxidized at the positive electrode side and reduced at the negative electrode side due to the influence of electric field force and diffusion force, so that the coulomb effect of the battery is reduced, active substances of the positive electrode are continuously lost, and the cycle performance of the battery is finally influenced.
In order to suppress the shuttle of polysulfide, reducing the pore size of the surface of the separator is a very effective solution. Interfacial polymerization is one of the common methods for preparing reverse osmosis membranes, and mainly utilizes two monomers with high activity to perform polymerization reaction at the interface of two mutually incompatible solvents, and a thin and compact layer is finally formed due to the self-limiting factor of the reaction. The thickness and the pore size of the diaphragm can be regulated and controlled by regulating and controlling the concentration of the reaction monomer, the reaction time and the like.
The composite membrane is compounded with a porous polyolefin lithium-sulfur battery membrane to form the lithium-sulfur battery composite membrane with high selectivity and high permeability, wherein the thin-layer interfacial membrane prepared by the interfacial polymerization method can improve the selectivity of a system, and the porous base membrane endows the membrane with certain mechanical property and permeability.
Disclosure of Invention
The purpose of the invention is as follows: the invention mainly aims to solve the problem of polysulfide shuttle flying in the current lithium-sulfur battery cycle process. In one aspect, a composite separator for a lithium sulfur battery is provided, comprising a base film and an interfacial film coating on a face-side surface of the base film facing the front side; on the other hand, the preparation method of the composite diaphragm for the lithium-sulfur battery is provided, the self-supporting interfacial film is prepared by adopting an interfacial polymerization method, and then the self-supporting interfacial film is transferred to a base film to be dried to form the composite diaphragm; finally, the use of the composite separator in a lithium sulfur battery is provided. The prepared composite diaphragm has high ion selective permeability due to small aperture and adjustable thickness, and can effectively improve the cycle performance and coulombic efficiency of the lithium-sulfur battery.
The technical scheme is as follows: in order to achieve the purpose, the invention adopts an interfacial polymerization method, two monomers are utilized to form a self-supporting polymer film at an oil-water interface through interfacial polymerization reaction, and the self-supporting polymer film is transferred to the surface of a base film to form a composite diaphragm.
The preparation method of the composite diaphragm is characterized by comprising the following steps:
(1) preparing an aqueous phase solution: dissolving water-soluble active monomer polyamine in water at room temperature to form a water phase containing water-soluble active monomer;
(2) preparing an organic phase solution: dissolving oil-soluble active monomer polybasic acyl chloride in an organic solvent at room temperature to form an organic phase containing the oil-soluble active monomer;
(3) flatly paving the base film on a flat substrate, placing the flat substrate in a container, pouring the aqueous phase solution prepared in the step (1) into the container to completely immerse the base film in the aqueous phase solution, and then adding the organic phase solution in the step (2);
(4) after the reaction, the formed self-supporting polymer film is supported by a flat plate; and drying at 25-100 ℃ to form the composite diaphragm for the lithium-sulfur battery.
The mass concentration of the water-soluble active monomer in the aqueous phase solution is 4-20 wt%, and the mass concentration of the water-soluble active monomer is preferably 8-10 wt%; the mass concentration of the active monomer in the organic phase is 0.4-2 wt%, and the mass concentration of the active monomer in the organic phase is preferably 0.8-1 wt%; the volume ratio of the organic phase to the aqueous phase is 1: (1-3).
The polyamine is one or more of triethylene tetramine, diethylenetriamine, hexanediamine, o-phenylenediamine, p-phenylenediamine, m-phenylenediamine and piperazine; the polybasic acyl chloride is one or more of benzene trimethyl acyl chloride, m-phthaloyl chloride, paraphthaloyl chloride and polybasic sulfonyl chloride;
the organic solvent used in the step (2) is one or more of dichloromethane, trichloromethane, benzene, toluene and cyclohexane.
The reaction time in the step (4) is 1-720min, and the preferable time is 3-60 min.
The base film is preferably a lipophilic membrane, including polyolefin-based films, such as: polyethylene film or polypropylene film.
The prepared composite diaphragm is in a structure that one side surface of the basement membrane is adhered with a layer of interfacial film coating, the thickness of the prepared interfacial film is 2-600nm, preferably 100-300nm, and the pore size is 1-30nm, preferably 1-10 nm.
Beneficial results
(1) The interfacial film in the composite diaphragm is formed by in-situ polymerization, and the thickness of the interfacial film is nano-scale, so that the ion transmission resistance of the diaphragm is greatly reduced; the pore diameter is nano-scale, so that the shuttle flying effect of polysulfide can be effectively relieved, and the cycle performance of the lithium-sulfur battery is improved.
(2) Oxygen-containing and nitrogen-containing functional groups on the selective interface film can form chemical bonding with polysulfide, so that the shuttle flying effect of the polysulfide is inhibited, and the cycle performance of the battery is improved.
(3) By regulating and controlling the reaction conditions, the invention can prepare the interface film thin layer with adjustable thickness and aperture size, and can effectively regulate and control the coulombic efficiency and the cycle performance of the lithium-sulfur battery in the cycle process.
(4) Self-supporting interfacial films prepared by interfacial polymerization methods have poor mechanical properties and are easily punctured by lithium dendrites to cause cell shorting and the like when used alone as separators in lithium sulfur batteries.
(5) The invention has simple preparation process, less time consumption and mild condition, and is favorable for further popularization and use.
Drawings
Fig. 1 is a graph of cycle performance at 0.2C for a lithium sulfur battery assembled from the composite separator prepared in example 6 and a comparative example.
The specific implementation mode is as follows:
the present invention will be further described with reference to the following examples, which are not intended to limit the scope of the invention. The examples were carried out according to the following implementation steps:
(1) preparing an aqueous phase solution: dissolving a water-soluble active monomer in water at room temperature to form an aqueous phase containing the water-soluble monomer;
(2) preparing an organic phase solution: dissolving an oil-soluble active monomer in n-hexane at room temperature to form an organic phase containing the oil-soluble active monomer;
(3) spreading a polypropylene porous membrane on a flat substrate, placing the flat substrate in a container, pouring the aqueous phase solution prepared in the step (1) into the container to enable the membrane to be completely immersed in the aqueous phase solution, and then adding the organic phase solution in the step (2);
(4) after reacting for a certain time, utilizing a flat plate to support the formed self-supporting polymer diaphragm; and drying at 25 ℃ to form the composite diaphragm for the lithium-sulfur battery.
The following tests were performed on the prepared composite films: 1) measuring the thickness of the interfacial film; 2) testing the surface aperture of the interface membrane; 3) testing the performance of the battery: and assembling the lithium-sulfur battery by using the prepared composite diaphragm, wherein one side of the composite boundary film is attached to the positive electrode. The carbon-sulfur compound C-S (S accounts for 60% of the mass of the carbon-sulfur compound), the lithium sheet and 1M LiTFSI (DOL/DME, volume ratio is 1:1) are respectively a positive electrode, a negative electrode and electrolyte. Wherein the positive electrode consists of 10 wt.% Super P carbon, 80 wt.% C-S and 10 wt.% polyvinylidene fluoride (PVDF), and the content of active substance S is 1.0mg/cm2(ii) a The dosage of the electrolyte is 40 mu L/(1 mg/cm)2S). After the assembled battery was left to stand at 25 ℃ for 5 hours, a charge and discharge test was performed at 0.2C with respect to the mass of the positive electrode active material.
Comparative example 1
The pore diameter of the commercial polypropylene diaphragm is between 50 and 350nm, and the thickness is 25 um; under the same conditions as in the implementation procedure, the cell performance was assembled and tested, and the coulombic efficiency of the cell at 0.2C was 77%.
It can be seen from the above examples that the prepared composite separator can significantly improve the coulombic efficiency and the cycle performance of the battery. The introduction of the interface thin layer effectively improves the ion selectivity of the membrane, blocks the 'shuttle flying' effect of polysulfide, and finally improves the coulombic efficiency and the cycle life of the battery.
Claims (8)
1. A preparation method of a composite diaphragm for a lithium-sulfur battery is characterized by comprising the following steps:
(1) preparing an aqueous phase solution: dissolving water-soluble active monomer polyamine in water at room temperature to form a water phase containing water-soluble active monomer;
(2) preparing an organic phase solution: dissolving oil-soluble active monomer polybasic acyl chloride in an organic solvent at room temperature to form an organic phase containing the oil-soluble active monomer;
(3) flatly paving the base film on a flat substrate, placing the flat substrate in a container, pouring the aqueous phase solution prepared in the step (1) into the container to completely immerse the base film in the aqueous phase solution, and then adding the organic phase solution in the step (2);
(4) after the reaction, the formed self-supporting polymer film is supported by a flat plate; and drying at 25-100 ℃ to form the composite diaphragm for the lithium-sulfur battery.
2. The method of claim 1, wherein: the mass concentration of the water-soluble active monomer in the aqueous phase solution is 4-20 wt%, and the mass concentration of the water-soluble active monomer is preferably 8-10 wt%; the mass concentration of the active monomer in the organic phase is 0.4-2 wt%, and the mass concentration of the active monomer in the organic phase is preferably 0.8-1 wt%; the volume ratio of the organic phase to the aqueous phase is 1: (1-3).
3. The method of claim 1, wherein: the polyamine is one or more of triethylene tetramine, diethylenetriamine, hexanediamine, o-phenylenediamine, p-phenylenediamine, m-phenylenediamine and piperazine; the polybasic acyl chloride is one or more of benzene trimethyl acyl chloride, m-phthaloyl chloride, p-phthaloyl chloride and polybasic sulfonyl chloride.
4. The method of claim 1, wherein: the organic solvent used in the step (2) is one or more of dichloromethane, trichloromethane, benzene, toluene and cyclohexane.
5. The method of claim 1, wherein: the reaction time in the step (4) is 1-720min, and the preferable time is 3-60 min.
6. The method of claim 1, wherein: the base film is preferably a lipophilic membrane, including polyolefin-based membranes.
7. A composite separator obtained by the production method as described in any one of claims 1 to 6, which has a structure in which an interfacial film coating is attached to one surface of a base film, and has an interfacial film thickness of 2 to 600nm, preferably 100 to 300nm, and a pore size of 1 to 30nm, preferably 1 to 10 nm.
8. Use of a composite separator according to claim 7 in a lithium-sulfur battery, wherein the composite interface film side faces or is conformed to the positive electrode.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811140113.6A CN110970587A (en) | 2018-09-28 | 2018-09-28 | Composite diaphragm for lithium-sulfur battery and preparation and application thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811140113.6A CN110970587A (en) | 2018-09-28 | 2018-09-28 | Composite diaphragm for lithium-sulfur battery and preparation and application thereof |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN110970587A true CN110970587A (en) | 2020-04-07 |
Family
ID=70027773
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201811140113.6A Pending CN110970587A (en) | 2018-09-28 | 2018-09-28 | Composite diaphragm for lithium-sulfur battery and preparation and application thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN110970587A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114512769A (en) * | 2020-10-23 | 2022-05-17 | 中国石油化工股份有限公司 | Lithium-sulfur battery diaphragm, preparation method thereof and lithium-sulfur battery |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5368889A (en) * | 1993-04-16 | 1994-11-29 | The Dow Chemical Company | Method of making thin film composite membranes |
| CN102802772A (en) * | 2009-06-18 | 2012-11-28 | 波音公司 | Methods And Systems For Incorporation Carbon Nanotubes Into Thin Film Composite Reverse Osmosis Membranes |
| CN103081172A (en) * | 2010-09-06 | 2013-05-01 | 株式会社Lg化学 | Separator, production method for same and electrochemical device equipped with same |
| CN105679982A (en) * | 2016-01-29 | 2016-06-15 | 中南大学 | Modification method for lithium-sulfur battery diaphragm |
| CN106450110A (en) * | 2016-11-09 | 2017-02-22 | 华中科技大学 | Preparation method of battery separator and product thereof |
-
2018
- 2018-09-28 CN CN201811140113.6A patent/CN110970587A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5368889A (en) * | 1993-04-16 | 1994-11-29 | The Dow Chemical Company | Method of making thin film composite membranes |
| CN102802772A (en) * | 2009-06-18 | 2012-11-28 | 波音公司 | Methods And Systems For Incorporation Carbon Nanotubes Into Thin Film Composite Reverse Osmosis Membranes |
| CN103081172A (en) * | 2010-09-06 | 2013-05-01 | 株式会社Lg化学 | Separator, production method for same and electrochemical device equipped with same |
| CN105679982A (en) * | 2016-01-29 | 2016-06-15 | 中南大学 | Modification method for lithium-sulfur battery diaphragm |
| CN106450110A (en) * | 2016-11-09 | 2017-02-22 | 华中科技大学 | Preparation method of battery separator and product thereof |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114512769A (en) * | 2020-10-23 | 2022-05-17 | 中国石油化工股份有限公司 | Lithium-sulfur battery diaphragm, preparation method thereof and lithium-sulfur battery |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN109167012B (en) | Multilayer composite structure diaphragm, preparation method thereof and lithium-sulfur battery | |
| CN106450327B (en) | A method of irradiation improves lithium battery Kynoar gluing performance | |
| EP3776691A1 (en) | Coating slurries for preparing separators, separators for electrochemical devices and preparation methods therefor | |
| CN108878733B (en) | Electrochemical device isolating membrane coating and preparation method and application thereof | |
| CN105261760A (en) | Lithium ion battery waterborne positive electrode composite collector, positive plate, manufacturing methods for lithium ion battery waterborne positive electrode composite collector and positive plate, and lithium ion battery | |
| CN110993358A (en) | Flexible zinc ion capacitor | |
| CN110957455A (en) | Functionalized diaphragm for lithium-sulfur battery and preparation method thereof | |
| CN111540868A (en) | Preparation method and application of two-dimensional manganese dioxide modified polypropylene diaphragm | |
| CN109755644B (en) | Gel composite polymer electrolyte membrane, preparation method thereof and lithium ion battery | |
| CN112615111A (en) | High-liquid-retention self-repairing diaphragm, preparation method thereof and lithium ion battery | |
| CN110970587A (en) | Composite diaphragm for lithium-sulfur battery and preparation and application thereof | |
| CN116830312A (en) | Water system positive pole piece, secondary battery comprising same and power utilization device | |
| CN111916629B (en) | Composite solid electrolyte diaphragm and preparation method and application thereof | |
| WO2019108027A1 (en) | Method for manufacturing electrode for secondary battery | |
| CN111740077A (en) | Lithium ion battery pole piece, preparation method of coating diaphragm on lithium ion battery pole piece and battery | |
| CN115863753B (en) | Gel electrolyte diaphragm and preparation method and application thereof | |
| CN113097442A (en) | Electrode and preparation method thereof | |
| KR20180060252A (en) | Adsorption film of polysulfide, separator comprising the same, lithium-sulfur battery and manufacturing method thereof | |
| CN113206252B (en) | Soybean protein-based multifunctional double-chain cross-linked sulfur cathode aqueous binder and preparation method and application thereof | |
| CN114188664B (en) | Lithium supplement isolating membrane and preparation method thereof, and battery cell containing lithium supplement isolating membrane and preparation method thereof | |
| US20230134434A1 (en) | Separator, preparation method and battery | |
| CN102867971B (en) | Silane guanidine-based composite anionic membrane, its preparation and application | |
| JP4161437B2 (en) | Lithium battery | |
| KR20160069385A (en) | Electrode composite, electrochemical device comprising the same and preparation method of the electrode composite | |
| CN114512769A (en) | Lithium-sulfur battery diaphragm, preparation method thereof and lithium-sulfur battery |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20200407 |