WO2023015521A1 - 隔离膜、锂离子电池、电池模块、电池包和用电装置 - Google Patents

隔离膜、锂离子电池、电池模块、电池包和用电装置 Download PDF

Info

Publication number
WO2023015521A1
WO2023015521A1 PCT/CN2021/112255 CN2021112255W WO2023015521A1 WO 2023015521 A1 WO2023015521 A1 WO 2023015521A1 CN 2021112255 W CN2021112255 W CN 2021112255W WO 2023015521 A1 WO2023015521 A1 WO 2023015521A1
Authority
WO
WIPO (PCT)
Prior art keywords
organic
inorganic
inorganic particles
sio
lithium
Prior art date
Application number
PCT/CN2021/112255
Other languages
English (en)
French (fr)
Inventor
谢庭祯
欧阳少聪
付成华
王博
叶永煌
Original Assignee
宁德时代新能源科技股份有限公司
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by 宁德时代新能源科技股份有限公司 filed Critical 宁德时代新能源科技股份有限公司
Priority to EP21936240.7A priority Critical patent/EP4160767A4/en
Priority to KR1020227036435A priority patent/KR20230025382A/ko
Priority to JP2022563084A priority patent/JP2023539970A/ja
Priority to PCT/CN2021/112255 priority patent/WO2023015521A1/zh
Priority to CN202180083358.3A priority patent/CN116601817A/zh
Priority to US18/087,713 priority patent/US20230127767A1/en
Publication of WO2023015521A1 publication Critical patent/WO2023015521A1/zh

Links

Images

Classifications

    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/40Separators; Membranes; Diaphragms; Spacing elements inside cells
    • H01M50/409Separators, membranes or diaphragms characterised by the material
    • H01M50/446Composite material consisting of a mixture of organic and inorganic materials
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/40Separators; Membranes; Diaphragms; Spacing elements inside cells
    • H01M50/403Manufacturing processes of separators, membranes or diaphragms
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00Secondary cells; Manufacture thereof
    • H01M10/05Accumulators with non-aqueous electrolyte
    • H01M10/052Li-accumulators
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00Secondary cells; Manufacture thereof
    • H01M10/05Accumulators with non-aqueous electrolyte
    • H01M10/052Li-accumulators
    • H01M10/0525Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/10Primary casings; Jackets or wrappings
    • H01M50/14Primary casings; Jackets or wrappings for protecting against damage caused by external factors
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/10Primary casings; Jackets or wrappings
    • H01M50/147Lids or covers
    • H01M50/155Lids or covers characterised by the material
    • H01M50/16Organic material
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/20Mountings; Secondary casings or frames; Racks, modules or packs; Suspension devices; Shock absorbers; Transport or carrying devices; Holders
    • H01M50/204Racks, modules or packs for multiple batteries or multiple cells
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/40Separators; Membranes; Diaphragms; Spacing elements inside cells
    • H01M50/409Separators, membranes or diaphragms characterised by the material
    • H01M50/411Organic material
    • H01M50/414Synthetic resins, e.g. thermoplastics or thermosetting resins
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/40Separators; Membranes; Diaphragms; Spacing elements inside cells
    • H01M50/409Separators, membranes or diaphragms characterised by the material
    • H01M50/431Inorganic material
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/40Separators; Membranes; Diaphragms; Spacing elements inside cells
    • H01M50/409Separators, membranes or diaphragms characterised by the material
    • H01M50/443Particulate material
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/40Separators; Membranes; Diaphragms; Spacing elements inside cells
    • H01M50/409Separators, membranes or diaphragms characterised by the material
    • H01M50/449Separators, membranes or diaphragms characterised by the material having a layered structure
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/40Separators; Membranes; Diaphragms; Spacing elements inside cells
    • H01M50/409Separators, membranes or diaphragms characterised by the material
    • H01M50/449Separators, membranes or diaphragms characterised by the material having a layered structure
    • H01M50/451Separators, membranes or diaphragms characterised by the material having a layered structure comprising layers of only organic material and layers containing inorganic material
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/40Separators; Membranes; Diaphragms; Spacing elements inside cells
    • H01M50/409Separators, membranes or diaphragms characterised by the material
    • H01M50/449Separators, membranes or diaphragms characterised by the material having a layered structure
    • H01M50/457Separators, membranes or diaphragms characterised by the material having a layered structure comprising three or more layers
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/40Separators; Membranes; Diaphragms; Spacing elements inside cells
    • H01M50/489Separators, membranes, diaphragms or spacing elements inside the cells, characterised by their physical properties, e.g. swelling degree, hydrophilicity or shut down properties
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M2220/00Batteries for particular applications
    • H01M2220/20Batteries in motive systems, e.g. vehicle, ship, plane
    • YGENERAL 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
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02EREDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/10Energy storage using batteries

Definitions

  • the present application relates to the technical field of lithium batteries, in particular to a separator and a lithium-ion battery containing it, a battery module, a battery pack and an electrical device.
  • lithium-ion batteries With the popularization of consumer electronics and new energy vehicles, consumers have put forward higher requirements for the battery life and service life of lithium-ion batteries. For current lithium-ion batteries, under the premise of ensuring low production costs, designing a lithium-ion battery with excellent storage performance and good power performance has become one of the main research and development directions.
  • lithium manganese oxide has been widely used due to its abundant raw materials, simple preparation, low price, and high safety. However, during the deep charge and discharge process, the storage performance and power performance of lithium-ion batteries prepared from lithium manganese oxide materials have not been effectively improved.
  • the present invention has been accomplished in view of the above-mentioned problems, and its object is to provide a separator capable of effectively improving battery storage performance while having good power performance, and to provide a lithium ion battery, a battery module, a battery pack and a separator including the same. electric device.
  • the first aspect of the present application provides a separator, the separator includes a base film and an organic-inorganic hybrid layer located on at least one surface of the base film, the organic-inorganic hybrid layer includes inorganic particles and organic binders;
  • the inorganic particles are composed of first inorganic particles with a median diameter of micrometers and second inorganic particles with a median diameter of nanometers, and the median diameter D1 of the first inorganic particles in ⁇ m is the same as the The ratio of the median diameter value D2 of the second inorganic particles in nm satisfies 2 ⁇ D2/D1 ⁇ 55, and the first inorganic particles or the second inorganic particles are selected from (SiO x )(H 2 O) y and (M c+ ) b (SiO z ) a- ,
  • part of the first inorganic particles and/or the second inorganic particles protrude from the surface of the organic-inorganic hybrid layer of the separator of the present application.
  • the median particle diameter value D1 of the first inorganic particles in ⁇ m is 1-5, and the value of the second inorganic particles in nm is The median particle size value D2 is 10-55.
  • the number average molecular weight of the organic binder is 1 million to 5 million, such as 1 million to 3.6 million, 1 million to 2 million, 1%
  • the viscosity range of the aqueous solution at room temperature is 1000-5000mPa ⁇ s.
  • the organic binder is an alkali metal salt of a carboxylic acid containing a hydroxyl and/or carboxyl group, or a sulfonic acid containing a hydroxyl and/or carboxyl group. More than one in the alkali metal salt, further optional sodium carboxymethylcellulose (CMC-Na), sodium polyacrylate (PAA-Na), sodium polystyrene sulfonate (PSS-Na), sodium alginate ( SA) more than one.
  • CMC-Na carboxymethylcellulose
  • PAA-Na sodium polyacrylate
  • PSS-Na sodium polystyrene sulfonate
  • SA sodium alginate
  • the inorganic particles are Si, SiO 2 , H 2 SiO 3 , H 4 SiO 4 , K 2 SiO 3 , K 4 SiO 4 and Na One or more of 4 SiO 4 ; optionally, the first inorganic particles can be Si, SiO 2 , H 2 SiO 3 , H 4 SiO 4 , K 2 SiO 3 , K 4 SiO 4 and Na 4 SiO 4 or more, the second inorganic particles may be SiO 2 and/or K 2 SiO 3 .
  • the mass m1 of the first inorganic particles and the mass m2 of the second inorganic particles satisfy 0.5 ⁇ m1/m2 ⁇ 4.
  • the ratio A1/A2 of the mass content A1 of the organic binder to the mass content A2 of the inorganic particles is 0.1-25:100.
  • the mass content of the inorganic particles is 80%-99.9%, and the mass content of the organic binder is 0.1%-20%, in order The total mass of the organic-inorganic hybrid layer.
  • the thickness d1 of the organic-inorganic hybrid layer of the isolation film of the present application accounts for 20%-50% of the total thickness d of the isolation film, and the total thickness d of the isolation film is 6-25 ⁇ m.
  • the base film constituting the isolation film of the present application has a front side and a back side
  • the front side includes a front coating area and a front blank area, and the ratio of the area of the front coating area to the front blank area is 1 to 3 : 1
  • the back side includes a back side coating area and a back side blank area, the ratio of the area of the back side coating area to the back side blank area is 0.5 ⁇ 1:1, the front side coating area and the back side coating area
  • the surface is coated with the organic-inorganic hybrid layer.
  • the front and back of the base film are respectively coated with the organic-inorganic hybrid layer, and the mass content of the inorganic particles in the organic-inorganic hybrid layer on the front of the base film is not less than that of the organic particles on the back of the base film.
  • the mass content of inorganic particles in the inorganic mixed layer is not less than that of the organic particles on the back of the base film.
  • the blank area on the front side coincides with the orthographic projection of the coating area on the back side
  • the blank area on the back side coincides with the orthographic projection of the coating area on the front side
  • the coating area on the front side coincides with the orthographic projection of the coating area on the front side.
  • the surface of the reverse coating area is coated with the organic-inorganic hybrid layer.
  • the heat shrinkage rate of the separator film is 70% to 75% less than the heat shrinkage rate of the base film.
  • the second aspect of the present application provides a lithium ion battery, including the separator of the first aspect of the present application.
  • a third aspect of the present application provides a battery module including the lithium-ion battery of the second aspect of the present application.
  • the fifth aspect of the present application provides an electrical device, including one or more of the lithium-ion battery of the second aspect of the present application, the battery module of the third aspect of the present application, or the battery pack of the fourth aspect of the present application; Ion cells or battery modules or battery packs can be used as a power source for an electrical device or as an energy storage unit for an electrical device.
  • the battery module, battery pack and electrical device of the present application include the lithium ion battery provided by the present application, and thus have at least the same advantages as the lithium ion battery.
  • This application develops a separator with an organic-inorganic hybrid layer, through comprehensive regulation of the adaptability of the median particle size of the first inorganic particle and the second inorganic particle, and the rationality of controlling the micron-sized and nano-sized particles
  • a separator that can significantly reduce the number of transition metal ions in the electrolyte and have good ion permeability has been developed, thereby significantly improving the storage performance and power performance of lithium-ion batteries.
  • FIG. 1 is a schematic structural view of an isolation membrane according to an embodiment of the present application.
  • Fig. 3 is a schematic diagram of the front and back coating areas of the base film according to an embodiment of the present application.
  • FIG. 4 is a schematic diagram of a lithium ion battery according to an embodiment of the present application.
  • FIG. 5 is an exploded view of the lithium ion battery according to one embodiment of the present application shown in FIG. 4 .
  • FIG. 6 is a schematic diagram of a battery module according to an embodiment of the present application.
  • FIG. 7 is a schematic diagram of a battery pack according to an embodiment of the present application.
  • FIG. 8 is an exploded view of the battery pack according to one embodiment of the present application shown in FIG. 7 .
  • FIG. 9 is a schematic diagram of an electrical device according to an embodiment of the present application.
  • the numerical range "a-b” represents an abbreviated representation of any combination of real numbers between a and b, where a and b are both real numbers.
  • the numerical range "0-5" indicates that all real numbers between "0-5" have been listed in this article, and "0-5" is only an abbreviated representation of the combination of these values.
  • a certain parameter is an integer ⁇ 2
  • the method includes steps (a) and (b), which means that the method may include steps (a) and (b) performed in sequence, and may also include steps (b) and (a) performed in sequence.
  • steps (c) means that step (c) may be added to the method in any order, for example, the method may include steps (a), (b) and (c) , may also include steps (a), (c) and (b), may also include steps (c), (a) and (b) and so on.
  • the “comprising” and “comprising” mentioned in this application mean open or closed.
  • the “comprising” and “comprising” may mean that other components not listed may be included or included, or only listed components may be included or included.
  • the term "or” is inclusive unless otherwise stated.
  • the phrase "A or B” means “A, B, or both A and B.” More specifically, the condition "A or B” is satisfied by either of the following: A is true (or exists) and B is false (or does not exist); A is false (or does not exist) and B is true (or exists) ; or both A and B are true (or exist).
  • the metal manganese produced is equivalent to a "catalyst", which can catalyze the SEI film (Solid Electrolyte Interphase) on the surface of the negative electrode, so that the organic lithium components and inorganic lithium components in the SEI film can be rapidly decomposed, which in turn leads to the failure of the SEI film, and finally lead to degradation of battery electrical performance.
  • a catalyst which can catalyze the SEI film (Solid Electrolyte Interphase) on the surface of the negative electrode, so that the organic lithium components and inorganic lithium components in the SEI film can be rapidly decomposed, which in turn leads to the failure of the SEI film, and finally lead to degradation of battery electrical performance.
  • the continuous consumption of the electrolyte in the electrolyte also deteriorates the conductivity of the electrolyte and increases the migration resistance of lithium ions between the positive and negative electrodes, thereby aggravating the deterioration of battery impedance.
  • the present application provides a kind of separating film, and described separating film comprises base film and the organic-inorganic hybrid layer that is positioned at at least one surface of described base film, and described organic-inorganic hybrid layer comprises inorganic particles and organic binder ;
  • the organic-inorganic hybrid coating on the separator of the present application has the effect of physically blocking transition metal ions, so to a certain extent, it has the effect of delaying/impeding the migration of transition metal ions from the positive electrode to the negative electrode.
  • the (SiO x )(H 2 O) y , (M c+ ) b (SiO z ) a- particles of the present application in addition to the Si-OH groups themselves, the hydrofluoric acid produced during the battery cycle It just makes the whole electrolyte present an acidic environment, so that (SiO x )(H 2 O) y , (M c+ ) b (SiO z ) a- particles have Si-OH groups on the surface.
  • These inorganic particles with Si-OH groups on the surface can form hydrogen bonds with some groups of the organic binder of the present application, so that the inorganic particles of the present application and the organic binder of the present application can be bonded more firmly.
  • the inorganic particles (SiO x ) (H 2 O) y , (M c+ ) b (SiO z ) a- Special activity, so that the separator of this application can effectively capture hydrofluoric acid in the electrolyte while realizing its basic function of isolating positive and negative electrodes, thereby reducing or avoiding hydrofluoric acid Corrosion of the positive electrode material produces transition metal ions, thereby reducing the number of transition metal ions in the electrolyte, significantly reducing the number of transition metal ions migrating to the surface of the negative electrode, thereby greatly improving the storage performance and cycle performance of lithium-ion batteries.
  • the inorganic particles are composed of first inorganic particles with a median diameter in the micron order and second inorganic particles with a median diameter in the nanometer order.
  • “median particle size” and “median particle size (D50)” are used synonymously, and refer to: the corresponding particle size when the particle cumulative particle size distribution percentage reaches 50%, and its physical meaning is that the particle size is larger than Its particles account for 50% of the particles smaller than it also account for 50%, also known as the median particle size.
  • D1 and D2 are respectively used to represent the median particle diameter value of the first inorganic particle in ⁇ m and the median particle diameter value of the second inorganic particle in nm, and should not be confused with the median particle size Confused by diameter D50.
  • median particle size D1 refers to the particle size value in ⁇ m of the median particle size D50 of the first inorganic particles, indicating that the particle size corresponding to the cumulative particle size distribution percentage of 50% is D1 ⁇ m.
  • D50 is generally used to indicate the average particle size of particles; “micron-scale” refers to particle sizes with a median particle size greater than 0 and less than 1 mm, and “nano-scale” refers to particle sizes with a median particle size greater than 0 and less than 1 micron.
  • the combination of the micron-sized first inorganic particles and the nano-sized second inorganic particles when the median diameter D1 of the first inorganic particles in ⁇ m is the same as that of the second inorganic particles
  • the surface area for capturing hydrofluoric acid can be increased as much as possible through reasonable stacking of large and small particles, and on the other hand
  • it can also make the organic-inorganic mixed layer have a suitable pore structure, avoid hindering the transmission of lithium ions, and finally make the storage performance and power performance of lithium-ion batteries significantly improved. See Table 1 for details.
  • the value of D2/D1 may be 10, 25, 33.3, 55, or its value range is within the range formed by any two point values mentioned above.
  • This application develops a separator with an organic-inorganic hybrid layer, through comprehensive regulation of the adaptability of the median particle size of the first inorganic particle and the second inorganic particle, and the rationality of controlling the micron-sized and nano-sized particles
  • a separator that can significantly reduce the number of transition metal ions in the electrolyte and have good ion permeability has been developed, thereby significantly improving the storage performance and power performance of lithium-ion batteries.
  • part of the first inorganic particles and/or the second inorganic particles may protrude from the surface of the organic-inorganic hybrid layer.
  • the expression "part” here is only for the convenience of description, and is used to illustrate the existence of the first inorganic particles and/or the second inorganic particles protruding from the surface of the organic-inorganic hybrid layer, and does not mean The intention is to express a specific quantity.
  • the first inorganic particles and/or the second inorganic particles protruding from the surface of the organic-inorganic hybrid layer may account for 2wt% to 85wt% of the total weight of all inorganic particles, such as 5wt%, 20wt% , 50wt% or 80wt%, or its numerical range is within the range formed by any two of the above-mentioned values.
  • the inorganic particles protrude from the surface of the organic-inorganic mixed layer, which can realize the direct contact between the electrolyte and the inorganic particles, so that the inorganic particles on the isolation film can capture the hydrofluoric acid in the electrolyte in time and quickly, thereby reducing the impact of the electrolyte on the manganese acid.
  • the corrosion of lithium reduces the dissolution of transition metals, thereby improving the storage performance and power performance of the battery.
  • the median diameter D1 of the first inorganic particles in ⁇ m is 1-5
  • the median diameter D2 of the second inorganic particles in nm is 10-5. 55.
  • the median diameter of the first inorganic particles may be 1 ⁇ m, 1.2 ⁇ m, 1.5 ⁇ m, 2 ⁇ m, 3 ⁇ m, 5 ⁇ m or 6 ⁇ m
  • the median diameter of the second particles may be 10 nm, 30 nm, 50 nm, 55 nm Or 500nm, or its numerical range is within the range formed by any two point values above.
  • the median diameter of the first inorganic particle and the second inorganic particle in a suitable range can make the contact between the inorganic particle formed by the first inorganic particle and the second inorganic particle in the organic-inorganic hybrid layer and the electrolyte solution The larger the area, the better the capture effect of the inorganic particles on the hydrofluoric acid in the electrolyte.
  • inorganic particles with different median diameters in the present application can be obtained commercially or synthesized by methods known in the prior art. See Table A for the specific material sources involved in the examples of this application.
  • the average molecular weight of the organic binder used to prepare the separator described in the present application is 1 million to 5 million, such as 1 million to 3.6 million, 1 million to 2 million, and the viscosity of 1% aqueous solution at room temperature The range is 1000-5000mPa ⁇ s.
  • the molecular weight can be determined by methods commonly used by those skilled in the art, for example, it can be determined according to GB/T 21864-2008.
  • the viscosity can be measured according to methods commonly used by those skilled in the art, for example, it can be measured according to GB/T 10247-2008.
  • the surface of the organic binder described in this application has abundant carboxyl groups and/or hydroxyl groups, which can perform chelation reactions with manganese ions, thereby achieving the effect of capturing and fixing manganese ions, reducing or avoiding the migration of manganese ions to the negative electrode Catalyze the decomposition of SEI film to further improve the storage performance and power performance of the battery.
  • the inorganic particles are one or more of Si, SiO 2 , H 2 SiO 3 , H 4 SiO 4 , K 2 SiO 3 , K 4 SiO 4 and Na 4 SiO 4
  • the first inorganic particles may be more than one of Si, SiO 2 , H 2 SiO 3 , H 4 SiO 4 , K 2 SiO 3 , K 4 SiO 4 and Na 4 SiO 4
  • the second inorganic particles may be SiO 2 and/or K 2 SiO 3 .
  • Si-O-CO can be formed between the alkali metal salts of carboxylic acids containing hydroxyl and/or carboxyl groups, the alkali metal salts of sulfonic acids containing hydroxyl and/or carboxyl groups, and the siliceous inorganic particles described in this application.
  • the covalent bond of -R so that the organic-inorganic hybrid network of porous structure is formed in the organic-inorganic hybrid layer, which not only makes the bonding between the organic binder and the inorganic particles stronger, but also the organic-inorganic hybrid network of the porous structure
  • the formation of is also conducive to the free shuttle of lithium ions.
  • the inorganic particles Si, SiO 2 , H 2 SiO 3 , H 4 SiO 4 , K 2 SiO 3 , K 4 SiO 4 or Na 4 SiO 4 in the separator of this application can not only effectively capture Hydrofluoric acid can reduce the dissolution of transition metals in positive electrode materials, and can also form covalent bonds with organic binders to form organic-inorganic hybrid networks, thereby providing channels for the transmission of lithium ions.
  • the ratio A1/A2 of the mass content A1 of the organic binder to the mass content A2 of the inorganic particles is 0.1 ⁇ 25:100.
  • the A1/A2 may be 0.1, 2.5, 5.3, 11.9, 25, or its numerical range is within the range formed by any two of the above-mentioned values.
  • the mass content of the inorganic particles is 80%-99.9%, and the mass content of the organic binder is 0.1%-20%.
  • the total mass of the organic-inorganic hybrid layer is 0.1%-20%.
  • the organic-inorganic hybrid layer when the organic binder content is lower than 0.1%, the bonding strength between the organic-inorganic hybrid layer and the base film is low, the coating is easy to fall off, and the bonding effect is poor. It is not enough to form chemical bonds with inorganic particles, so that the inorganic particles are easy to fall off, resulting in a decrease in the capture rate of hydrofluoric acid in the electrolyte, which is not conducive to the improvement of battery storage and cycle performance.
  • the content of the organic binder is higher than 20%, the viscosity of the coating slurry is too high, the fluidity of the slurry is poor and difficult to prepare, and the organic binder does not provide battery capacity, and the addition of too much will reduce the energy density of the battery.
  • ensuring that the quality of the organic and inorganic components in the organic-inorganic mixed layer is within a suitable range can not only ensure the bonding strength between the isolation film and the coating, but also prevent the inorganic particles from falling off, and the toughness of the isolation film is within a reasonable range.
  • the energy density of the battery will not decrease, and the storage performance and power performance of the battery will be significantly improved. See Table 3 for details.
  • the ratio A1/m1 of the mass A1 of the organic binder to the mass m1 of the first inorganic particles may be 0.125 ⁇ 75:100.
  • the A1/m1 may be 0.25:100, 6.23:100, 13.21:100, 28.41:100 or 62.31:100, or its value range is within the range formed by any two of the above values.
  • the thickness d1 of the organic-inorganic hybrid layer accounts for 20%-50% of the total thickness d of the isolation film, and the total thickness d of the isolation film is 6-25 ⁇ m, such as 10 ⁇ m, 11 ⁇ m, 12 ⁇ m, 13 ⁇ m, 16 ⁇ m, 20 ⁇ m, 24 ⁇ m, or its numerical range is within the range formed by any two of the above values.
  • the total thickness d of the isolation film herein is the sum of the thickness d1 of the organic-inorganic hybrid layer and the thickness of the base film.
  • d1 is the sum of the thicknesses of the organic-inorganic hybrid layers on both sides of the base film.
  • the thickness d1 of the organic-inorganic hybrid layer accounts for 20%, 27%, 36%, 42%, 46% of the total thickness d of the isolation film, or its numerical range is composed of any two of the above values within range.
  • the maximum thickness d1 of the organic-inorganic hybrid layer accounts for 20%-50% of the total thickness d of the separator, at this time the relative ratio of the thickness of the organic-inorganic hybrid layer to the thickness of the separator Located within a reasonable range, it can not only ensure the efficient capture of hydrofluoric acid in the electrolyte, but also ensure that the air permeability of the separator is within a reasonable range, which is conducive to improving the storage performance of the battery. See Table 4 for details.
  • the mass content of inorganic particles in the organic-inorganic mixed layer on the front side of the base film is not less than the mass content of inorganic particles in the organic-inorganic mixed layer on the reverse side of the base film, and the base film
  • the organic-inorganic hybrid layer on the front side of the membrane is in contact with the positive electrode
  • the organic-inorganic hybrid layer on the reverse side of the base film is in contact with the negative electrode.
  • the front side of the base film includes a front coating area and a front blank area, and the area ratio of the front coating area to the front blank area is 1 to 3:1;
  • the The reverse side of the base film includes a reverse coated area and a reverse blank area, the area ratio of the reverse coated area to the reverse blank area is 0.5 to 1:1, and the surface of the front coated area and the reverse coated area Coated with the organic-inorganic hybrid layer.
  • the coating on the front side of the separator that is in contact with the positive pole piece is in direct contact with the active material, so it will preferentially capture hydrofluoric acid and dissolved transition metal ions, so the coating area on the front side of the separator needs to be designed larger than that on the back side, so that it can Guaranteed larger catches and faster catches.
  • the interval coating on the front and back can also reduce the deterioration of the coating on the air permeability and the hindrance to ion transmission.
  • the blank area on the front side coincides with the orthographic projection of the coating area on the back side
  • the blank area on the back side coincides with the orthographic projection of the coating area on the front side
  • the coating area on the front side The organic-inorganic hybrid layer is coated on the surface of the reverse coating area.
  • the mass content of inorganic particles in the organic-inorganic mixed layer on the front side of the base film is not less than the mass content of inorganic particles in the organic-inorganic mixed layer on the back side of the base film; - the inorganic mixed layer is in contact with the positive electrode, and the organic-inorganic mixed layer on the opposite side of the base film is in contact with the negative electrode.
  • the material of the base film can be selected from at least one of glass fiber, non-woven fabric, polyethylene, polypropylene and polyvinylidene fluoride.
  • the base film may be a single-layer film or a multi-layer composite film, without any particular limitation. When the base film is a multilayer composite film, the materials of each layer may be the same or different, and there is no particular limitation.
  • the organic-organic hybrid layer of the present application is located on at least one surface of a single-layer base film or a composite base film.
  • the positive electrode sheet includes a positive electrode collector and a positive electrode film layer arranged on at least one surface of the positive electrode collector, and the positive electrode film layer includes a positive electrode active material.
  • the positive electrode current collector has two opposing surfaces in its own thickness direction, and the positive electrode film layer is disposed on any one or both of the two opposing surfaces of the positive electrode current collector.
  • lithium transition metal oxides may include, but are not limited to, lithium cobalt oxides (such as LiCoO 2 ), lithium nickel oxides (such as LiNiO 2 ), lithium manganese oxides (such as LiMnO 2 , LiMn 2 O 4 ), lithium Nickel cobalt oxide, lithium manganese cobalt oxide, lithium nickel manganese oxide, lithium nickel cobalt manganese oxide (such as LiNi 1/3 Co 1/3 Mn 1/3 O 2 (also referred to as NCM 333 ), LiNi 0.5 Co 0.2 Mn 0.3 O 2 (also abbreviated as NCM 523 ), LiNi 0.5 Co 0.25 Mn 0.25 O 2 (also abbreviated as NCM 211 ), LiNi 0.6 Co 0.2 Mn 0.2 O 2 (also abbreviated as NCM 622 ), LiNi At least one of 0.8 Co 0.1 Mn 0.1 O 2 (also referred to as NCM 811 ), lithium nickel cobalt aluminum oxide (such as LiNi
  • the olivine structure contains Examples of lithium phosphates may include, but are not limited to, lithium iron phosphate (such as LiFePO 4 (also may be abbreviated as LFP)), composite materials of lithium iron phosphate and carbon, lithium manganese phosphate (such as LiMnPO 4 ), lithium manganese phosphate and carbon At least one of a composite material, lithium manganese iron phosphate, and a composite material of lithium manganese iron phosphate and carbon.
  • lithium iron phosphate such as LiFePO 4 (also may be abbreviated as LFP)
  • composite materials of lithium iron phosphate and carbon such as LiMnPO 4
  • LiMnPO 4 lithium manganese phosphate and carbon
  • the negative electrode sheet includes a negative electrode current collector and a negative electrode film layer arranged on at least one surface of the negative electrode current collector, and the negative electrode film layer includes a negative electrode active material.
  • the negative electrode film layer may also optionally include a conductive agent.
  • the conductive agent can be selected from at least one of superconducting carbon, acetylene black, carbon black, Ketjen black, carbon dots, carbon nanotubes, graphene and carbon nanofibers.
  • the present application also provides a lithium ion battery, including the separator described in the first aspect of the present application.
  • the above-mentioned positive electrode sheet, separator, and negative electrode sheet are wound to form an electrode assembly.
  • a lithium ion battery can include an outer packaging.
  • the outer package can be used to package the above-mentioned electrode assembly and electrolyte.
  • the battery module 4 may also include a housing with an accommodating space, and a plurality of lithium-ion batteries 5 are accommodated in the accommodating space.
  • the present application also provides an electric device, which includes at least one of the lithium-ion battery, battery module, or battery pack provided in the present application.
  • the lithium ion battery, battery module, or battery pack can be used as a power source of the electric device, and can also be used as an energy storage unit of the electric device.
  • the electric devices may include mobile devices (such as mobile phones, notebook computers, etc.), electric vehicles (such as pure electric vehicles, hybrid electric vehicles, plug-in hybrid electric vehicles, electric bicycles, electric scooters, electric golf carts, etc.) , electric trucks, etc.), electric trains, ships and satellites, energy storage systems, etc., but not limited thereto.
  • PE base film (Ningdezhuo High-tech Material Technology Co., Ltd., the thickness is 5 ⁇ m, 7 ⁇ m, 8 ⁇ m, 10 ⁇ m, please refer to the text description of the example for details)
  • Example 1-3 Mix the uniform slurry 1 and the organic binder solution 2 to form a mixed slurry, and coat the above-mentioned mixed slurry on both sides of a PP base film with a thickness of 7 ⁇ m (full surface coating), and the thickness of the front side of the base film is 2 ⁇ m, the coating thickness on the reverse side of the base film is 2 ⁇ m, and the isolation film of Example 1-3 is obtained after drying.
  • Artificial graphite, conductive agent carbon black, and binder CMC-Na are mixed according to a mass ratio of 8:1:1, and an appropriate amount of deionized water is added to make the solid content of the slurry 40-60wt%.
  • the negative electrode slurry was obtained under the action of a vacuum mixer; the negative electrode slurry was evenly coated on the copper foil of the negative electrode current collector; the copper foil was dried at room temperature and then transferred to a 120°C oven for drying for 1 hour, and then cold pressed and cut to obtain Negative pole piece.
  • the first inorganic particles are K 2 SiO 3 with a median diameter of 5 ⁇ m, K 2 SiO 3 with 2 ⁇ m , and K 2 with 1.2 ⁇ m SiO 3 , 1.5 ⁇ m K 2 SiO 3 , 1 ⁇ m K 2 SiO 3 , 1 ⁇ m H 2 SiO 3 , 1 ⁇ m Si, 1 ⁇ m SiO 2 , 1 ⁇ m SiO 2 , 1 ⁇ m SiO 2 , 3 ⁇ m SiO 2 , 5 ⁇ m SiO 2 of 1 ⁇ m, Si 3 N 4 of 1 ⁇ m, SiC of 1
  • the thickness d1 of the organic-inorganic mixed layer is 2 ⁇ m, 2 ⁇ m, 3 ⁇ m, 4 ⁇ m, 5 ⁇ m, 6 ⁇ m, 6 ⁇ m
  • the thickness of the base film is 10 ⁇ m, 8 ⁇ m, 8 ⁇ m, 7 ⁇ m, 7 ⁇ m, 7 ⁇ m , 5 ⁇ m, except that the base film of the isolation film is made of PE material, other preparation processes are the same as those of Examples 1-3.
  • the first inorganic particle K 2 SiO 3 (calculated as K 2 SiO 3 , 20g) (D1 is 1 ⁇ m)
  • the second inorganic particle K 2 SiO 3 (calculated as K 2 SiO 3 , 30g) (D2 is 10nm) according to the mass Mix evenly at a ratio of 2:3, add 125g of deionized water to the above mixture, stir for 2 hours to obtain a uniform slurry 1.
  • Mix the homogeneous slurry 1 with the organic binder solution 2 to form a mixed slurry.
  • the separators of the embodiment and the comparative example were respectively cut into test samples with a length of 100 mm and a width of 10 mm. Take a stainless steel plate with a width of 25mm, paste it with double-sided adhesive tape (width 11mm), paste the test sample on the double-sided adhesive tape on the stainless steel plate, and use a 2000g pressure roller to roll back and forth on its surface three times (300mm/min).

Landscapes

  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Inorganic Chemistry (AREA)
  • Materials Engineering (AREA)
  • Manufacturing & Machinery (AREA)
  • Composite Materials (AREA)
  • Cell Separators (AREA)

Abstract

本申请开发出一种具有有机-无机混合层的隔离膜,通过综合调控第一无机颗粒和第二无机颗粒的中值粒径的适应性搭配关系,以及控制微米级和纳米级颗粒的合理性搭配,开发出一种能够显著降低电解液中过渡金属离子,并兼具良好离子透过率的隔离膜,从而显著提高锂离子电池的循环性能、存储性能。

Description

隔离膜、锂离子电池、电池模块、电池包和用电装置 技术领域
本申请涉及锂电池技术领域,尤其涉及一种隔离膜及包含其的锂离子电池、电池模块、电池包和用电装置。
背景技术
随着消费类电子产品和新能源汽车的普及,消费者对锂离子电池的续航能力和使用寿命提出了更高的要求。对于目前的锂离子电池,在保证较低制备成本的前提下,设计出一款存储性能优良并兼具良好功率性能的锂离子电池成为主要研发方向之一。
在锂离子电池常用的正极活性材料中,锰酸锂凭借其原材料丰富、制备简单、价格低廉、安全性高而得到广泛应用。但是,在深度充放电过程中,由锰酸锂材料制备的锂离子电池的存储性能和功率性能一直无法得到有效改善。
发明内容
本发明是鉴于上述课题而完成的,其目的在于,提供一种能够有效改善电池存储性能并同时兼具良好功率性能的隔离膜,并提供包括其的锂离子电池、电池模块、电池包和用电装置。
为了达到上述目的,本申请的第一方面提供一种隔离膜,所述隔离膜包括基膜和位于所述基膜至少一个表面的有机-无机混合层,所述有机-无机混合层包括无机颗粒和有机粘结质;
所述无机颗粒由中值粒径在微米级的第一无机颗粒和中值粒径在纳米级的第二无机颗粒组成,所述第一无机颗粒以μm计的中值粒径数值D1与所述第二无机颗粒以nm计的中值粒径数值D2之比满足2≤D2/D1≤55,并且,所述第一无机颗粒或所述第二无机颗粒选自(SiO x)(H 2O) y和(M c+) b(SiO z) a-
其中,0≤x≤2,0≤y≤2且y为整数;z=3或4,a=2或4,b×c=a;M可以为锂、钠、钾、镁、钙、铝中的一种或多种。
在任意实施方式中,部分所述第一无机颗粒和/或所述第二无机颗粒凸出于本申请隔离膜有机-无机混合层表面。
在任意实施方式中,在本申请隔离膜的有机-无机混合层中,所述第一无机颗粒以μm计的中值粒径数值D1为1~5,所述第二无机颗粒以nm计的中值粒径数值D2为10~55。
在任意实施方式中,在本申请隔离膜的有机-无机混合层中,所述有机粘结质的数均分子量为100-500万,例如100万-360万、100万-200万,1%水溶液常温下粘度范围为1000-5000mPa·s。
在任意实施方式中,在本申请隔离膜的有机-无机混合层中,所述有机粘结质为含有羟基和/或羧基的羧酸的碱金属盐、含有羟基和/或羧基的磺酸的碱金属盐中的一种以上,进一步可选为羧甲基纤维素钠(CMC-Na)、聚丙烯酸钠(PAA-Na)、聚苯乙烯磺酸钠(PSS-Na)、海藻酸钠(SA)中的一种以上。
在任意实施方式中,在本申请隔离膜的有机-无机混合层中,所述无机颗粒为Si、SiO 2、H 2SiO 3、H 4SiO 4、K 2SiO 3、K 4SiO 4和Na 4SiO 4中的一种或多种;可选地,所述第一无机颗粒可选为Si、SiO 2、H 2SiO 3、H 4SiO 4、K 2SiO 3、K 4SiO 4和Na 4SiO 4中的一种以上,所述第二无机颗粒可选为SiO 2和/或K 2SiO 3
在任意实施方式中,在本申请隔离膜的有机-无机混合层中,所述第一无机颗粒质量m1与所述第二无机颗粒的质量m2满足0.5≤m1/m2≤4。
在任意实施方式中,在本申请隔离膜的有机-无机混合层中,所述有机粘结质质量含量A1和所述无机颗粒的质量含量A2之比A1/A2为0.1~25:100。
在任意实施方式中,在本申请隔离膜的有机-无机混合层中,所述无机颗粒的质量含量为80%-99.9%,所述有机粘结质的质量含量为0.1%-20%,以所述有机-无机混合层的总质量计。
在任意实施方式中,本申请隔离膜有机-无机混合层的厚度d1占 所述隔离膜总厚度d的20%-50%,隔离膜总厚度d为6-25μm。
在任意实施方式中,组成本申请隔离膜的基膜具有正面和反面,正面包括正面涂覆区和正面空白区,所述正面涂覆区与所述正面空白区的面积之比为1~3:1;反面包括反面涂覆区和反面空白区,所述反面涂覆区与所述反面空白区的面积之比为0.5~1:1,所述正面涂覆区与所述反面涂覆区表面涂有所述有机-无机混合层。
在任意实施方式中,所述基膜的正反面分别涂有所述有机-无机混合层,所述基膜正面的有机-无机混合层中无机颗粒的质量含量不小于所述基膜反面的有机-无机混合层中无机颗粒的质量含量;所述基膜正面的有机-无机混合层与正极相接触,所述基膜反面的有机-无机混合层与负极相接触。
在任意实施方式中,进一步地,所述正面空白区与所述反面涂覆区的正投影重合,所述反面空白区与所述正面涂覆区的正投影重合,所述正面涂覆区与所述反面涂覆区表面涂有所述有机-无机混合层。
在任意实施方式中,所述隔离膜的热收缩率比所述基膜热收缩率少70%~75%。
本申请的第二方面提供一种锂离子电池,包括本申请第一方面的隔离膜。
本申请的第三方面提供一种电池模块,包括本申请第二方面的锂离子电池。
本申请的第四方面提供一种电池包,包括本申请第二方面的锂离子电池或本申请第三方面的电池模块中的一种以上。
本申请的第五方面提供一种用电装置,包括本申请第二方面的锂离子电池、本申请第三方面的电池模块或本申请第四方面的电池包中的一种以上;所述锂离子电池或电池模块或电池包可用作用电装置的电源或用电装置的能量存储单元。
本申请的电池模块、电池包和用电装置包括本申请提供的锂离子电池,因而至少具有与所述锂离子电池相同的优势。
[有益效果]
本申请开发出一种具有有机-无机混合层的隔离膜,通过综合调控第一无机颗粒和第二无机颗粒的中值粒径的适应性搭配关系,以及控制微米级和纳米级颗粒的合理性搭配,开发出一种能够显著降低电解液中过渡金属离子数量,并兼具良好离子透过率的隔离膜,从而显著提高锂离子电池的存储性能、功率性能。
附图说明
图1是本申请一实施方式的隔离膜的结构示意图。
图2是本申请一实施方式的隔离膜的结构示意图。
图3是本申请一实施方式的基膜的正反面涂覆区示意图。
图4是本申请一实施方式的锂离子电池的示意图。
图5是图4所示的本申请一实施方式的锂离子电池的分解图。
图6是本申请一实施方式的电池模块的示意图。
图7是本申请一实施方式的电池包的示意图。
图8是图7所示的本申请一实施方式的电池包的分解图。
图9是本申请一实施方式的用电装置的示意图。
附图标记说明:
1电池包
2上箱体
3下箱体
4电池模块
5二次电池
51壳体
52电极组件
53顶盖组件
具体实施方式
以下,适当地参照附图详细说明具体公开了本申请的隔离膜及包含其的锂离子电池、电池模块、电池包和用电装置的实施方式。但是 会有省略不必要的详细说明的情况。例如,有省略对已众所周知的事项的详细说明、实际相同结构的重复说明的情况。这是为了避免以下的说明不必要地变得冗长,便于本领域技术人员的理解。此外,附图及以下说明是为了本领域技术人员充分理解本申请而提供的,并不旨在限定权利要求书所记载的主题。
本申请所公开的“范围”以下限和上限的形式来限定,给定范围是通过选定一个下限和一个上限进行限定的,选定的下限和上限限定了特定范围的边界。这种方式进行限定的范围可以是包括端值或不包括端值的,并且可以进行任意地组合,即任何下限可以与任何上限组合形成一个范围。例如,如果针对特定参数列出了60-120和80-110的范围,则理解为60-110和80-120的范围也是预料到的。此外,如果列出的最小范围值1和2,和如果列出了最大范围值3,4和5,则下面的范围可全部预料到:1-3、1-4、1-5、2-3、2-4和2-5。在本申请中,除非有其他说明,数值范围“a-b”表示a到b之间的任意实数组合的缩略表示,其中a和b都是实数。例如数值范围“0-5”表示本文中已经全部列出了“0-5”之间的全部实数,“0-5”只是这些数值组合的缩略表示。另外,当表述某个参数为≥2的整数,则相当于公开了该参数为例如整数2、3、4、5、6、7、8、9、10、11、12等。
本申请中使用的术语“以上”、“以下”包含本数,例如“一种以上”是指一种或多种,“A和B中的一种以上”是指“A”、“B”或“A和B”。
如果没有特别的说明,本申请的所有实施方式以及可选实施方式可以相互组合形成新的技术方案。
如果没有特别的说明,本申请的所有技术特征以及可选技术特征可以相互组合形成新的技术方案。
如果没有特别的说明,本申请的所有步骤可以顺序进行,也可以随机进行,优选是顺序进行的。例如,所述方法包括步骤(a)和(b),表示所述方法可包括顺序进行的步骤(a)和(b),也可以包括顺序进行的步骤(b)和(a)。例如,所述提到所述方法还可包括步骤(c),表示步骤(c)可以任意顺序加入到所述方法,例如,所述方法可以包括步骤(a)、 (b)和(c),也可包括步骤(a)、(c)和(b),也可以包括步骤(c)、(a)和(b)等。
如果没有特别的说明,本申请所提到的“包括”和“包含”表示开放式,也可以是封闭式。例如,所述“包括”和“包含”可以表示还可以包括或包含没有列出的其他组分,也可以仅包括或包含列出的组分。
如果没有特别的说明,在本申请中,术语“或”是包括性的。举例来说,短语“A或B”表示“A,B,或A和B两者”。更具体地,以下任一条件均满足条件“A或B”:A为真(或存在)并且B为假(或不存在);A为假(或不存在)而B为真(或存在);或A和B都为真(或存在)。
经过长期制备锂离子电池的经验,本申请发明人发现:对于含有过渡金属的锰酸锂材料,在深度充放电过程中,其结构容易发生晶格畸变,并易受到浸润其结构的电解液的腐蚀(特别是电解液分解产生的氢氟酸的腐蚀),而使原本结构内的Mn 3+和/或Mn 4+从锰酸锂晶格结构中溶出,并在电化学氧化还原反应中进一步歧化成Mn 2+,这些产生的Mn 2+在电势差的作用下逐渐迁移到负极表面,并被进一步还原成金属锰。这些产生的金属锰相当于“催化剂”,能够催化负极表面SEI膜(固态电解质界面膜,Solid Electrolyte Interphase),使SEI膜中的有机锂成分和无机锂成分快速分解,进而导致SEI膜失效,最终导致电池电性能下降。
SEI膜被“催化”分解后,损失的SEI膜在电池充放电过程中被补充,故电解液和电池内部的活性锂不断被消耗,并转化为新SEI膜中的有机锂/无机锂组分,这就使得真正起到充放电贡献的活性锂含量降低,给电池循环和存储性能带来不可逆影响;其次,金属锰催化分解SEI膜的过程伴随系列副产物的产生,这些副产物沉积于负极表面,阻碍锂离子进出负极的通道,进而造成电池阻抗增加。同时,电解液中电解质的不断消耗也使电解液的导电性变差,也增加了锂离子在正负极间的迁移阻力,从而加剧电池阻抗恶化。
经过大量实验和研究,发明人发现,降低过渡金属锰对电池的负 面效应可以从以下思路入手:第一方面,物理阻隔锰酸锂产生的Mn 2+迁移到负极表面;第二方面,化学消除锰酸锂产生的Mn 2+,进而降低甚至消除其迁移到负极。如上两种方式或两种方式的协同作用都能显著降低分解SEI膜的金属锰。因此,发明人从协同两方面的作用出发,通过对隔离膜的结构特征和化学成分进行综合改性,充分协同利用上述两方面的作用,设计出能够显著降低负极表面过渡金属的隔离膜,大幅提高了锂离子电池的循环性能和存储性能。
值得一提的是,本申请的隔离膜同时也兼具良好的透气性,并不会影响锂离子在隔离膜内部的自由传输,也并不会降低锂离子在隔离膜内部的传输速率。
[隔离膜]
参照图1,本申请提供一种隔离膜,所述隔离膜包括基膜和位于所述基膜至少一个表面的有机-无机混合层,所述有机-无机混合层包括无机颗粒和有机粘结质;
所述无机颗粒由中值粒径在微米级的第一无机颗粒和中值粒径在纳米级的第二无机颗粒组成,所述第一无机颗粒以μm计的中值粒径数值D1与所述第二无机颗以nm计的中值粒径数值D2之比满足2≤D2/D1≤55,并且,所述第一无机颗粒或所述第二无机颗粒选自(SiO x)(H 2O) y、(M c+) b(SiO z) a-,其中,0≤x≤2,0≤y≤2且y为整数;z=3或4,a=2或4,b×c=a;M可以为锂、钠、钾、镁、钙、铝中的一种或多种。
本申请隔离膜上的有机-无机混合涂层,具有物理阻隔过渡金属离子的作用,故在一定程度上具有延缓/阻碍过渡金属离子从正极迁移到负极的作用。
本申请所述有机-无机混合层是由有机粘结质和无机颗粒混合构成的具有预定厚度的结构,有机粘结质能够将不具有粘性物质的无机颗粒牢固粘结在基膜上,进而防止电池存储或循环过程中无机颗粒脱落。
进一步地,本申请的(SiO x)(H 2O) y、(M c+) b(SiO z) a-颗粒除本身带有的Si-OH基团以外,电池循环过程中产生的氢氟酸恰好使电解液整体 呈现酸性环境,从而使(SiO x)(H 2O) y、(M c+) b(SiO z) a-颗粒表面带上Si-OH基团。这些表面具有Si-OH基团的无机颗粒能够与本申请有机粘结质自身的某些基团形成氢键,从而使本申请无机颗粒与本申请的有机粘结质粘结得更牢固。
经过大量实验验证,在特定的锂离子电池电解液的环境中,加之电池内部因电化学反应构成的复杂环境,能够赋予本申请的无机颗粒(SiO x)(H 2O) y、(M c+) b(SiO z) a-特殊的活性,从而使本申请的隔离膜在实现其基础隔离正负极功能的同时,还能够有效捕获电解液中的氢氟酸,从而减少或避免氢氟酸腐蚀正极材料而产生过渡金属离子,进而降低电解液中过渡金属离子的数量,显著降低过渡金属离子迁移到负极表面的数量,从而大幅提高锂离子电池的存储性能和循环性能。
本申请中,所述无机颗粒由中值粒径在微米级的第一无机颗粒和中值粒径在纳米级的第二无机颗粒组成。在本文中,“中值粒径”与“中值粒径(D50)”同义使用,是指:颗粒累计粒度分布百分数达到50%时所对应的粒径,它的物理意义是粒径大于它的颗粒占50%小于它的颗粒也占50%,也叫中位粒径。需要说明的是,“D1”和“D2”分别用于表示第一无机颗粒以μm计的中值粒径数值和第二无机颗粒以nm计的中值粒径数值,不应与中值粒径D50相混淆。例如,“中值粒径D1”是指第一无机颗粒的中值粒径D50以μm计的粒径数值,表示颗粒累积粒度分布百分数达到50%时所对应的粒径为D1μm。D50一般用来表示颗粒的平均粒度;“微米级”是指颗粒中值粒径大于0小于1毫米的颗粒尺寸,“纳米级”是指颗粒中值粒径大于0小于1微米的颗粒尺寸。
本申请中,有机-无机混合层中,微米级的第一无机颗粒与纳米级第二无机颗粒的组合搭配,当所述第一无机颗粒以μm计的中值粒径数值D1与所述第二无机颗粒以nm计的中值粒径数值D2之比满足2≤D2/D1≤55时,一方面能够通过大小颗粒的合理堆砌,尽可能增大用于捕获氢氟酸的表面积,另一方面还能够使有机-无机混合层具有合适的孔隙结构,避免阻碍锂离子的传输,最终使得锂离子电池的存储性能、功率性能得到显著提升。具体参见表1。
需要说明的是,D2/D1仅代表具体数值的比值,并未包括单位;例如,D2=10nm,D1=1μm,则D2/D1=10/1=10。
可选地,所述D2/D1的值可以为10、25、33.3、55,或者其数值范围在上述任意两个点值构成的范围内。
本申请开发出一种具有有机-无机混合层的隔离膜,通过综合调控第一无机颗粒和第二无机颗粒的中值粒径的适应性搭配关系,以及控制微米级和纳米级颗粒的合理性搭配,开发出一种能够显著降低电解液中过渡金属离子数量,并兼具良好离子透过率的隔离膜,从而显著提高锂离子电池的存储性能、功率性能。
在一些实施方式中,参见图2,部分所述第一无机颗粒和/或所述第二无机颗粒可以凸出于所述有机-无机混合层表面。需要说明的是,这里的表述“部分”仅是为了描述的方便,用以说明存在凸出于所述有机-无机混合层表面的第一无机颗粒和/或所述第二无机颗粒,并不意图表示具体数量。尽管如此,凸出于所述有机-无机混合层表面的所述第一无机颗粒和/或所述第二无机颗粒可以占所有无机颗粒总重量的2wt%~85wt%,例如5wt%、20wt%、50wt%或80wt%,或者其数值范围在上述任意两个值组成的范围内。
无机颗粒凸出于有机-无机混合层表面,能够实现电解液与无机颗粒地直接接触,使隔离膜上地无机颗粒及时且快速地捕获电解液中的氢氟酸,从而降低电解液对锰酸锂的腐蚀,降低过渡金属溶出,从而提高电池的存储性能和功率性能。
在一些实施方式中,可选地,所述第一无机颗粒以μm计的中值粒径数值D1为1~5,所述第二无机颗粒以nm计的中值粒径数值D2为10~55。
例如,所述第一无机颗粒的中值粒径可以为1μm、1.2μm、1.5μm、2μm、3μm、5μm或6μm,所述第二颗粒的中值粒径可以为10nm、30nm、50nm、55nm或500nm,或者其数值范围在上述任意两个点值构成的范围内。
本申请中,第一无机颗粒与第二无机颗粒合适范围的中值粒径,能够使有机-无机混合层中由第一无机颗粒和第二无机颗粒搭配而成 的无机颗粒与电解液的接触面积较大,使无机颗粒对电解液中氢氟酸的捕获效果更佳。
需要说明的是,本申请具有不同中值粒径的无机颗粒均可市售获得或通过现有技术已知的方法合成。本申请实施例中涉及到的具体物质来源详见表A。
在一些实施方式中,可选地,用于制备本申请所述隔离膜的有机粘结质平均分子量为100-500万例如100万-360万、100万-200万,1%水溶液常温下粘度范围为1000-5000mPa·s。所述分子量可通过本领域技术人员通常使用的方法测定,例如可根据GB/T 21864-2008测定。所述粘度可根据本领域技术人员通常使用的方法测定,例如可根据GB/T 10247-2008测定。
在一些实施方式中,可选地,所述有机粘结质为含有羟基和/或羧基的羧酸的碱金属盐、含有羟基和/或羧基的磺酸的碱金属盐中的一种以上,进一步可选为羧甲基纤维素钠(CMC-Na)、聚丙烯酸钠(PAA-Na)、聚苯乙烯磺酸钠(PSS-Na)、海藻酸钠(SA)中的一种以上。
需要说明的是,本申请所述的有机粘结质表面具有丰富的羧基和/或羟基,能够与锰离子进行螯合反应,从而达到捕获固定锰离子的作用,减少或避免锰离子迁移到负极催化SEI膜分解,进一步提高电池的存储性能和功率性能。
在一些实施方式中,可选地,所述无机颗粒为Si、SiO 2、H 2SiO 3、H 4SiO 4、K 2SiO 3、K 4SiO 4和Na 4SiO 4中的一种或多种;可选地,所述第一无机颗粒可选为Si、SiO 2、H 2SiO 3、H 4SiO 4、K 2SiO 3、K 4SiO 4和Na 4SiO 4中的一种以上,所述第二无机颗粒可选为SiO 2和/或K 2SiO 3
本申请中,含有羟基和/或羧基的羧酸的碱金属盐、含有羟基和/或羧基的磺酸的碱金属盐与本申请所述的硅质无机颗粒之间能够形成Si-O-CO-R的共价键,从而使有机-无机混合层中形成多孔结构的有机-无机混合网络,不仅使有机粘结质和无机颗粒之间的粘结更牢固,而且多孔结构有机-无机混合网络的形成也有利于锂离子的自由穿梭。
需要说明的是,本申请隔离膜中的无机颗粒Si、SiO 2、H 2SiO 3、H 4SiO 4、K 2SiO 3、K 4SiO 4或Na 4SiO 4不仅能够有效捕获电解液中的氢氟酸,降低正极材料中过渡金属溶出,还能够与有机粘结质形成共价键,生成有机-无机混合网络,进而为锂离子的传输提供通道。
在一些实施方式中,可选地,在所述有机-无机混合层中,所述第一无机颗粒质量m1与所述第二无机颗粒的质量m2满足0.5≤m1/m2≤4。
本申请有机-无机混合层中,第一无机颗粒与第二无机颗粒合理的质量配比有助于提高有机-无机混合层中捕获电解液中氢氟酸的比表面积,提高对电解液中氢氟酸的捕捉量。具体参见表2。
可选地,所述m1/m2可以为0.5、0.67、1.2、2.5、4.0,或者其数值范围在上述任意两个数值组成的范围内。
在一些实施方式中,可选地,在所述有机-无机混合层中,所述有机粘结质质量含量A1和所述无机颗粒的质量含量A2之比A1/A2为0.1~25:100。可选地,所述A1/A2可以为0.1、2.5、5.3、11.9、25,或者其数值范围在上述任意两个值组成的范围内。
在一些实施方式中,可选地,所述有机-无机混合层中,所述无机颗粒的质量含量为80%-99.9%,所述有机粘结质的质量含量为0.1%-20%,以所述有机-无机混合层的总质量计。
在有机-无机混合层中,当有机粘结质含量低于0.1%时,有机-无机混合层与基膜的粘结强度低,涂层易脱落,粘结效果差,同时有机粘结质也不足以与无机颗粒形成化学键,从而使无机颗粒易于脱落,导致对电解液中氢氟酸的捕捉率降低,不利于电池存储和循环性能提高。当有机粘结质的含量高于20%时,涂层浆料粘度过高,浆料流动性差不易制备,且有机粘结质不提供电池容量,加入量过高会降低电池能量密度。因此,保证有机-无机混合层中,有机成分与无机成分质量在合适范围内,既能保证隔离膜与涂层的粘结强度,又能防止无机颗粒脱落,并且隔离膜的韧度在合理范围内,电池的能量密度也不会降低,电池的存储性能和功率性能得到显著改善。具体参见表3。
在一些实施方式中,可选地,所述有机粘结质的质量A1与所述 第一无机颗粒的质量m1之比A1/m1可以为0.125~75:100。
可选地,所述A1/m1可以为0.25:100、6.23:100、13.21:100、28.41:100或62.31:100,或者其数值范围在上述任意两个值组成的范围内。
在一些实施方式中,可选地,所述有机粘结质的质量A1与所述第二无机颗粒的质量m2之比A1/m2可以为0.15~125:100。
可选地,所述A1/m2可以为0.17:100、4.18:100、8.85:100、19:100或41.75:100,或者其数值范围在上述任意两个值组成的范围内。
在一些实施方式中,可选地,所述有机-无机混合层的厚度d1占所述隔离膜总厚度d的20%-50%,隔离膜总厚度d为6-25μm,例如10μm、11μm、12μm、13μm、16μm、20μm、24μm,或者其数值范围在上述任意两个值组成的范围内。需要说明的是,本文中所述隔离膜总厚度d为有机-无机混合层的厚度d1与基膜厚度之和。在基膜正反两面均进行涂覆时,d1为基膜正反两面有机-无机混合层的厚度之和。
可选地,所述有机-无机混合层的厚度d1占所述隔离膜总厚度d的20%、27%、36%、42%、46%,或者其数值范围在上述任意两个值组成的范围内。
锂离子电池隔膜厚度需小于25μm(USABC,美国先进电池联盟,United States Advanced Battery Consortium,规定)。若隔离膜涂层厚度低于20%,同时基膜本身厚度薄,如5μm,单面涂层厚度则低于0.5μm,商业化的加工难度大;若有机-无机混合层厚度高于50%,则透气度不满足使用要求,离子电导率低,电池倍率性能下降明显,对电池存储性能和功率性能也造成不利影响。
基于隔离膜的总厚度计,所述有机-无机混合层的最大厚度d1占所述隔离膜总厚度d的20%-50%,此时有机-无机混合层的厚度与隔离膜厚度的相对比例位于合理范围内,既能保证对电解液中氢氟酸的高效捕获,又能保证隔离膜的透气度位于合理范围内,有利于提高电池的存储性能。具体参见表4。
在一些实施方式中,可选地,所述基膜正面的有机-无机混合层 中无机颗粒的质量含量不小于所述基膜反面的有机-无机混合层中无机颗粒的质量含量,所述基膜正面的有机-无机混合层与正极接触,所述基膜反面的有机-无机混合层与负极接触。需要说明的是,本文中将基膜朝向正极的一侧称为“基膜正面”,将基膜朝向负极的一侧称为“基膜反面”。
与正极极片接触隔离膜正面上的涂层,与正极活性物质直接接触,因此会优先捕获氢氟酸以及部分溶出的过渡金属离子,故作为一种可实施方式,隔离膜正面混合层中无机颗粒质量含量可以比反面大,同时两者均优选不低于95%,这样才能更多、更快速地捕获氢氟酸。
在一些实施方式中,可选地,所述基膜正面包括正面涂覆区和正面空白区,所述正面涂覆区与所述正面空白区的面积之比为1~3:1;所述基膜反面包括反面涂覆区和反面空白区,所述反面涂覆区与所述反面空白区的面积之比为0.5~1:1,所述正面涂覆区与所述反面涂覆区表面涂有所述有机-无机混合层。
与正极极片接触的隔离膜正面上的涂层,与活性物质直接接触,因此会优先捕获氢氟酸以及溶出的过渡金属离子,所以隔离膜正面涂层面积需要设计的比反面大,这样能保证更大的捕获量以及更快速的捕获。同时,正反面间隔涂覆,也能降低涂层对透气度的恶化,对离子传输的阻碍,因此,正反面涂覆重叠区域也不宜过大:当正面涂覆区与所述正面空白区的面积之比低于1:1,反面涂覆区与所述反面空白区的面积之比低于0.5:1时,说明涂层涂覆量过少,并不能起到较好的捕获作用;而当正面涂覆区与所述正面空白区的面积之比高于3:1,反面涂覆区与所述反面空白区的面积之比高于1:1时,说明涂覆量过高,对透气度影响较大。当正面涂覆区与所述正面空白区的面积之比在1~3:1内,反面涂覆区与所述反面空白区的面积之比在0.5~1:1时,能够兼顾氢氟酸捕获量以及透气度。具体参见表5。
可选地,所述基膜正面包括正面涂覆区和正面空白区,所述正面涂覆区与所述正面空白区的面积之比可以为1:1、1.5:1、3:1,或者其数值范围在上述任意两个比值组成的范围内;所述基膜反面包括反面涂覆区和反面空白区,所述反面涂覆区与所述反面空白区的面积 之比可以为0.5:1、0.67:1、1:1,或者其数值范围在上述任意两个比值组成的范围内。
在一些实施方式中,可选地,所述正面空白区与所述反面涂覆区的正投影重合,所述反面空白区与所述正面涂覆区的正投影重合,所述正面涂覆区与所述反面涂覆区表面涂有所述有机-无机混合层。具体可参照图3。
上述正面空白区与反面涂覆区的正投影重合,反面空白区与正面涂覆区的正投影重合的涂覆方式,能够兼顾制备成本、隔离膜透气度、高效捕捉氢氟酸的优势。
在一些实施方式中,所述基膜正面的有机-无机混合层中无机颗粒的质量含量不小于所述基膜反面的有机-无机混合层中无机颗粒的质量含量;所述基膜正面的有机-无机混合层与正极相接触,所述基膜反面的有机-无机混合层与负极相接触。
正面的有机-无机混合层因与含有锰酸锂的正极膜层直接接触,故“正面的有机-无机混合层中无机颗粒的质量含量不小于所述基膜反面的有机-无机混合层中无机颗粒的质量含量”对降低过渡金属离子含量改善更有效,并且能够同时兼顾隔离膜的整体透气度,进而同时改善电池的存储性能和功率性能。具体参见表6。
在一些实施方式中,可选地,所述隔离膜的热收缩率比所述基膜热收缩率少70%~75%。经过实验验证,经过本申请改性的隔离膜的热收缩率得到显著改善。例如,假设未经改性的常规聚丙烯(PP)材料的隔离膜为100%,则本申请改性后的隔离膜的热收缩率仅有20%~25%。本文中所述热收缩率可通过本领域通常使用的方法进行测定,例如可根据GB/T 13519-2016测定。
本申请对隔离膜基膜的种类没有特别的限制,可以选用任意公知的具有良好的化学稳定性和机械稳定性的多孔基膜。
在一些实施方式中,基膜的材质可选自玻璃纤维、无纺布、聚乙烯、聚丙烯及聚偏二氟乙烯中的至少一种。基膜可以是单层薄膜,也可以是多层复合薄膜,没有特别限制。在基膜为多层复合薄膜时,各层的材料可以相同或不同,没有特别限制。本申请的有机-有机混合 层位于单层基膜或复合基膜的至少一个表面。
[正极极片]
正极极片包括正极集流体以及设置在正极集流体至少一个表面的正极膜层,所述正极膜层包括正极活性材料。
作为示例,正极集流体具有在其自身厚度方向相对的两个表面,正极膜层设置在正极集流体相对的两个表面的其中任意一者或两者上。
在一些实施方式中,所述正极集流体可采用金属箔片或复合集流体。例如,作为金属箔片,可采用铝箔。复合集流体可包括高分子材料基层和形成于高分子材料基层至少一个表面上的金属层。复合集流体可通过将金属材料(铝、铝合金、镍、镍合金、钛、钛合金、银及银合金等)形成在高分子材料基材(如聚丙烯(PP)、聚对苯二甲酸乙二醇酯(PET)、聚对苯二甲酸丁二醇酯(PBT)、聚苯乙烯(PS)、聚乙烯(PE)等的基材)上而形成。
在一些实施方式中,正极活性材料可采用本领域公知的用于电池的正极活性材料。作为示例,正极活性材料可包括以下材料中的至少一种:橄榄石结构的含锂磷酸盐、锂过渡金属氧化物及其各自的改性化合物。但本申请并不限定于这些材料,还可以使用其他可被用作电池正极活性材料的传统材料。这些正极活性材料可以仅单独使用一种,也可以将两种以上组合使用。其中,锂过渡金属氧化物的示例可包括但不限于锂钴氧化物(如LiCoO 2)、锂镍氧化物(如LiNiO 2)、锂锰氧化物(如LiMnO 2、LiMn 2O 4)、锂镍钴氧化物、锂锰钴氧化物、锂镍锰氧化物、锂镍钴锰氧化物(如LiNi 1/3Co 1/3Mn 1/3O 2(也可以简称为NCM 333)、LiNi 0.5Co 0.2Mn 0.3O 2(也可以简称为NCM 523)、LiNi 0.5Co 0.25Mn 0.25O 2(也可以简称为NCM 211)、LiNi 0.6Co 0.2Mn 0.2O 2(也可以简称为NCM 622)、LiNi 0.8Co 0.1Mn 0.1O 2(也可以简称为NCM 811)、锂镍钴铝氧化物(如LiNi 0.85Co 0.15Al 0.05O 2)及其改性化合物等中的至少一种。橄榄石结构的含锂磷酸盐的示例可包括但不限于磷酸铁锂(如LiFePO 4(也可以简称为LFP))、磷酸铁锂与碳的复合材料、磷酸锰锂(如LiMnPO 4)、磷酸锰锂与碳的复合材料、磷酸锰铁锂、磷 酸锰铁锂与碳的复合材料中的至少一种。
在一些实施方式中,正极膜层还可选地包括粘结剂。作为示例,所述粘结剂可以包括聚偏氟乙烯(PVDF)、聚四氟乙烯(PTFE)、偏氟乙烯-四氟乙烯-丙烯三元共聚物、偏氟乙烯-六氟丙烯-四氟乙烯三元共聚物、四氟乙烯-六氟丙烯共聚物及含氟丙烯酸酯树脂中的至少一种。
在一些实施方式中,正极膜层还可选地包括导电剂。作为示例,所述导电剂可以包括超导碳、乙炔黑、炭黑、科琴黑、碳点、碳纳米管、石墨烯及碳纳米纤维中的至少一种。
在一些实施方式中,可以通过以下方式制备正极极片:将上述用于制备正极极片的组分,例如正极活性材料、导电剂、粘结剂和任意其他的组分分散于溶剂(例如N-甲基吡咯烷酮)中,形成正极浆料;将正极浆料涂覆在正极集流体上,经烘干、冷压等工序后,即可得到正极极片。
[负极极片]
负极极片包括负极集流体以及设置在负极集流体至少一个表面上的负极膜层,所述负极膜层包括负极活性材料。
作为示例,负极集流体具有在其自身厚度方向相对的两个表面,负极膜层设置在负极集流体相对的两个表面中的任意一者或两者上。
在一些实施方式中,所述负极集流体可采用金属箔片或复合集流体。例如,作为金属箔片,可以采用铜箔。复合集流体可包括高分子材料基层和形成于高分子材料基层至少一个表面上的金属层。复合集流体可通过将金属材料(铜、铜合金、镍、镍合金、钛、钛合金、银及银合金等)形成在高分子材料基材(如聚丙烯(PP)、聚对苯二甲酸乙二醇酯(PET)、聚对苯二甲酸丁二醇酯(PBT)、聚苯乙烯(PS)、聚乙烯(PE)等的基材)上而形成。
在一些实施方式中,负极活性材料可采用本领域公知的用于电池的负极活性材料。作为示例,负极活性材料可包括以下材料中的至少一种:人造石墨、天然石墨、软炭、硬炭、硅基材料、锡基材料和钛酸锂等。所述硅基材料可选自单质硅、硅氧化合物、硅碳复合物、硅 氮复合物以及硅合金中的至少一种。所述锡基材料可选自单质锡、锡氧化合物以及锡合金中的至少一种。但本申请并不限定于这些材料,还可以使用其他可被用作电池负极活性材料的传统材料。这些负极活性材料可以仅单独使用一种,也可以将两种以上组合使用。
在一些实施方式中,负极膜层还可选地包括粘结剂。所述粘结剂可选自丁苯橡胶(SBR)、聚丙烯酸(PAA)、聚丙烯酸钠(PAAS)、聚丙烯酰胺(PAM)、聚乙烯醇(PVA)、海藻酸钠(SA)、聚甲基丙烯酸(PMAA)及羧甲基壳聚糖(CMCS)中的至少一种。
在一些实施方式中,负极膜层还可选地包括导电剂。导电剂可选自超导碳、乙炔黑、炭黑、科琴黑、碳点、碳纳米管、石墨烯及碳纳米纤维中的至少一种。
在一些实施方式中,负极膜层还可选地包括其他助剂,例如增稠剂(如羧甲基纤维素钠(CMC-Na))等。
在一些实施方式中,可以通过以下方式制备负极极片:将上述用于制备负极极片的组分,例如负极活性材料、导电剂、粘结剂和任意其他组分分散于溶剂(例如去离子水)中,形成负极浆料;将负极浆料涂覆在负极集流体上,经烘干、冷压等工序后,即可得到负极极片。
[电解液]
电解液在正极极片和负极极片之间起到传导离子的作用。所述电解液包括电解质盐和溶剂。
在一些实施方式中,电解质盐可选自六氟磷酸锂、四氟硼酸锂、高氯酸锂、六氟砷酸锂、双氟磺酰亚胺锂、双三氟甲磺酰亚胺锂、三氟甲磺酸锂、二氟磷酸锂、二氟草酸硼酸锂、二草酸硼酸锂、二氟二草酸磷酸锂及四氟草酸磷酸锂中的至少一种。
在一些实施方式中,溶剂可选自碳酸亚乙酯、碳酸亚丙酯、碳酸甲乙酯、碳酸二乙酯、碳酸二甲酯、碳酸二丙酯、碳酸甲丙酯、碳酸乙丙酯、碳酸亚丁酯、氟代碳酸亚乙酯、甲酸甲酯、乙酸甲酯、乙酸乙酯、乙酸丙酯、丙酸甲酯、丙酸乙酯、丙酸丙酯、丁酸甲酯、丁酸乙酯、1,4-丁内酯、环丁砜、二甲砜、甲乙砜及二乙砜中的至少一种。
在一些实施方式中,所述电解液还可选地包括添加剂。例如添加 剂可以包括负极成膜添加剂、正极成膜添加剂,还可以包括能够改善电池某些性能的添加剂,例如改善电池过充性能的添加剂、改善电解液产气的添加剂、提高SEI膜稳定性的添加剂、改善电池高温或低温性能的添加剂等。
[锂离子电池]
本申请还提供一种锂离子电池,包括本申请第一方面所述的隔离膜。上述正极极片、隔离膜、负极极片卷绕成电极组件。
在一些实施方式中,锂离子电池可包括外包装。该外包装可用于封装上述电极组件及电解质。
在一些实施方式中,锂离子电池的外包装可以是硬壳,例如硬塑料壳、铝壳、钢壳等。锂离子电池的外包装也可以是软包,例如袋式软包。软包的材质可以是塑料,作为塑料,可列举出聚丙烯、聚对苯二甲酸丁二醇酯以及聚丁二酸丁二醇酯等。
本申请对锂离子电池的形状没有特别的限制,其可以是圆柱形、方形或其他任意的形状。例如,图4是作为一个示例的方形结构的锂离子电池5。
在一些实施方式中,参照图5,外包装可包括壳体51和盖板53。其中,壳体51可包括底板和连接于底板上的侧板,底板和侧板围合形成容纳腔。壳体51具有与容纳腔连通的开口,盖板53能够盖设于所述开口,以封闭所述容纳腔。正极极片、负极极片和隔离膜可经卷绕工艺或叠片工艺形成电极组件52。电极组件52封装于所述容纳腔内。电解液浸润于电极组件52中。锂离子电池5所含电极组件52的数量可以为一个或多个,本领域技术人员可根据具体实际需求进行选择。
在一些实施方式中,锂离子电池可以组装成电池模块,电池模块所含锂离子电池的数量可以为一个或多个,具体数量本领域技术人员可根据电池模块的应用和容量进行选择。
图6是作为一个示例的电池模块4。参照图6,在电池模块4中,多个锂离子电池5可以是沿电池模块4的长度方向依次排列设置。当 然,也可以按照其他任意的方式进行排布。进一步可以通过紧固件将该多个锂离子电池5进行固定。
可选地,电池模块4还可以包括具有容纳空间的外壳,多个锂离子电池5容纳于该容纳空间。
在一些实施方式中,上述电池模块还可以组装成电池包,电池包所含电池模块的数量可以为一个或多个,具体数量本领域技术人员可根据电池包的应用和容量进行选择。
图7和图8是作为一个示例的电池包1。参照图7和图8,在电池包1中可以包括电池箱和设置于电池箱中的多个电池模块4。电池箱包括上箱体2和下箱体3,上箱体2能够盖设于下箱体3,并形成用于容纳电池模块4的封闭空间。多个电池模块4可以按照任意的方式排布于电池箱中。
另外,本申请还提供一种用电装置,所述用电装置包括本申请提供的锂离子电池、电池模块、或电池包中的至少一种。所述锂离子电池、电池模块、或电池包可以用作所述用电装置的电源,也可以用作所述用电装置的能量存储单元。所述用电装置可以包括移动设备(例如手机、笔记本电脑等)、电动车辆(例如纯电动车、混合动力电动车、插电式混合动力电动车、电动自行车、电动踏板车、电动高尔夫球车、电动卡车等)、电气列车、船舶及卫星、储能系统等,但不限于此。
作为所述用电装置,可以根据其使用需求来选择锂离子电池、电池模块或电池包。
图9是作为一个示例的用电装置。该用电装置为纯电动车、混合动力电动车、或插电式混合动力电动车等。为了满足该用电装置对锂离子电池的高功率和高能量密度的需求,可以采用电池包或电池模块。
作为另一个示例的装置可以是手机、平板电脑、笔记本电脑等。该装置通常要求轻薄化,可以采用锂离子电池作为电源。
实施例
以下,说明本申请的实施例。下面描述的实施例是示例性的,仅 用于解释本申请,而不能理解为对本申请的限制。实施例中未注明具体技术或条件的,按照本领域内的文献所描述的技术或条件或者按照产品说明书进行。所用试剂或仪器未注明生产厂商者,均为本领域通常使用的可以通过市购获得的常规产品。本申请实施例中各成分的含量,如果没有特别说明,均以不含结晶水的质量计。
以下描述用语:“实施例1-1的隔离膜”是指实施例1-1的锂离子电池制备过程中的所用的隔离膜;“实施例1-1的正极极片”是指实施例1-1的锂离子电池制备过程中的所用的正极极片;“实施例1-1的负极极片”是指实施例1-1的锂离子电池制备过程中的所用的负极极片;“实施例1-1的电解液”是指实施例1-1的锂离子电池制备过程中的所用的电解液;“实施例1-1的锂离子电池”是指由实施例1-1的正极、隔离膜、负极、电解液制备而成的锂离子电池。
本申请实施例涉及的原材料来源:
表A.1:
Figure PCTCN2021112255-appb-000001
Figure PCTCN2021112255-appb-000002
(其中√表示适用,--表示不适用;下同)
表A.2:
Figure PCTCN2021112255-appb-000003
其他原材料:
CMC-Na(CAS:9004-32-4,C804622,麦克林试剂网)
PAA-Na(CAS:9003-04-07,S818399,麦克林试剂网)
SA(CAS:9005-38-3,S902506,麦克林试剂网)
PSS-Na(CAS:25704-18-1,P874965,麦克林试剂网)
PP基膜(宁德卓高新材料科技有限公司,厚度为7μm)
PE基膜(宁德卓高新材料科技有限公司,厚度分别为5μm、7μm、8μm、10μm,具体使用哪种厚度规格详见实施例文字说明)
实施例1-3
【隔离膜的制备】
将第一无机颗粒K 2SiO 3(以K 2SiO 3计,20g)(D1为1μm)、第二无机颗粒SiO 2(以SiO 2计,30g)(D2为10nm)按照质量比2:3均匀混合,取125g去离子水加入到上述混合物中,搅拌2h得到均一浆料1。按照有机粘结质:无机颗粒=5:95(即A1/A2=5.3:100)的质量比称量合适量的有机粘结质PAA-Na,加入524.7g水搅拌2h得 到有机粘结质溶液2。将均一浆料1与有机粘结质溶液2混合成混合浆料,将上述混合浆料涂布在7μm厚度的PP基膜正反两面上(整面涂覆),基膜正面涂覆厚度为2μm,基膜反面涂覆厚度为2μm,烘干后得到实施例1-3的隔离膜。
【正极极片的制备】
将正极活性材料LiMn 2O 4、LiNi 0.8Co 0.1Mn 0.1O 2、粘结剂聚偏氟乙烯、导电剂乙炔黑按照质量比4.8:3.2:1:1进行混合,加入适量的溶剂NMP(N-甲基吡咯烷酮),使浆料固含量为50-80wt%。在真空搅拌机作用下获得正极浆料;将正极浆料均匀涂敷在正极集流体铝箔上;将铝箔在室温下晾干后转移至120℃烘箱干燥1h,然后经过冷压、分切得到正极极片。
【负极极片的制备】
将人造石墨、导电剂碳黑、粘结剂CMC-Na,按照质量比8:1:1进行混合,加入适量去离子水,使浆料固含量为40-60wt%。在真空搅拌机作用下获得负极浆料;将负极浆料均匀涂覆在负极集流体铜箔上;将铜箔在室温下晾干后转移至120℃烘箱干燥1h,然后经过冷压、分切得到负极极片。
【电解液的制备】
按照1:1的体积比取适量EC(碳酸乙烯酯)、DMC(碳酸二甲酯)溶液搅拌均匀后得到混合溶液。往所述混合溶液中加入适量LiPF 6,搅拌至溶解完全,配置成LiPF 6浓度为1mol/L的溶液,即为电解液。
【锂离子电池的制备】
将正极极片、隔离膜、负极极片放置于上料位,调整入料位,确保隔离膜处于正、负极极片之间起到隔离的作用,卷绕得到裸电芯;将裸电芯置于壳体中,注入电解液,经过真空封装、静置、化成、整形等工序,获得锂离子电池。
实施例1-1、1-2、1-4~1-13、对比例C1~C4
除有机粘结质分别为PAA-Na、PAA-Na、PAA-Na、PAA-Na、PAA-Na、PAA-Na、PAA-Na、PAA-Na、PSS-Na、SA-Na、PAA-Na、 PAA-Na、PAA-Na、PAA-Na、PAA-Na、PAA-Na,第一无机颗粒分别为中值粒径5μm的K 2SiO 3、2μm的K 2SiO 3、1.2μm的K 2SiO 3、1.5μm的K 2SiO 3、1μm的K 2SiO 3、1μm的H 2SiO 3、1μm的Si、1μm的SiO 2、1μm的SiO 2、1μm的SiO 2、3μm的SiO 2、5μm的SiO 2、1μm的Si 3N 4、1μm的SiC、3μm的K 2SiO 3、6μm的K 2SiO 3,第二无机颗粒分别为中值粒径10nm的SiO 2、10nm的SiO 2、30nm的SiO 2、55nm的SiO 2、55nm的SiO 2、10nm的SiO 2、10nm的SiO 2、10nm的SiO 2、10nm的SiO 2、10nm的SiO 2、30nm的Si、50nm的K 2SiO 3、10nm的SiO 2、10nm的SiO 2、500nm的SiO 2、10nm的SiO 2以外,其他制备工艺与实施例1-3相同。
实施例2-1~2-7
除有机粘结质为SA,m1/m2分别为0.4、0.5、0.67、1.2、2.5、4.0、5,隔离膜基膜为PE材料以外,其他制备工艺与实施例1-3相同。
实施例3-1~3-7
有机-无机混合层中,除有机粘结质的质量A1分别为0.93mg、2mg、46mg、100.7mg、252mg、448mg、594mg,无机颗粒的质量A2分别为1.55g、2.0g、1.84g、1.90g、2.12g、1.79g、1.97g,有机粘结质为PSS-Na以外,其他制备工艺与实施例1-3相同。
实施例4-1~4-7
除有机粘结质为CMC-Na,有机-无机混合层的厚度d1分别为2μm、2μm、3μm、4μm、5μm、6μm、6μm,基膜厚度分别为10μm、8μm、8μm、7μm、7μm、7μm、5μm,隔离膜基膜为PE材料以外,其他制备工艺与实施例1-3相同。
实施例5-3
【隔离膜的制备】按照如下所述方法:
将第一无机颗粒K 2SiO 3(以K 2SiO 3计,20g)(D1为1μm)、第二无机颗粒K 2SiO 3(以K 2SiO 3计,30g)(D2为10nm)按照质量比2:3均匀混合,取125g去离子水加入到上述混合物中,搅拌2h得到均一浆料1。按照有机粘结质质量A1(mg)与无机颗粒质量A2(g)的 比A1/A2=5.3%,称量合适量2.65g的有机粘结质CMC-Na,加入524.7g水搅拌2h得到有机粘结质溶液2。将均一浆料1与有机粘结质溶液2混合成混合浆料。
对厚度为7μm的PE材质的基膜的正反两面进行涂覆区与空白区的划分,使得正面涂覆区与正面空白区的面积比为1.5:1,使得反面涂覆区与反面空白区的面积比为0.67:1,将上述混合浆料均匀涂覆于正反面的涂覆区,正反两面涂覆区的涂覆厚度分别为3μm,烘干后得到实施例5-3的隔离膜。
【正极极片的制备】、【负极极片的制备】、【电解液的制备】、【锂离子电池的制备】工艺与实施例1-1相同。
实施例5-1~5-2、5-4~5-5
除基膜正面涂覆区与正面空白区的面积比分别为0.85:1、1:1、3:1、3.5:1,基膜反面涂覆区与反面空白区的面积比分别为0.48:1、0.5:1、1:1、1.5:1以外,其他制备工艺与实施例5-3相同。
实施例6-1~实施例6-4
除基膜正面有机-无混合层中无机颗粒的质量含量分别为95%、95%、98%、95%,基膜反面有机-无混合层中无机颗粒的质量含量分别为80%、95%、95%、93%以外,其他制备工艺与实施例5-3相同。
【隔离膜相关参数测试】
1、有机-无机混合层与基膜之间的剥离力(即表3中所述粘结力)测试
将实施例和对比例的隔离膜,分别裁成长100mm、宽10mm的测试样品。取一条宽度25mm的不锈钢板,贴双面胶(宽度11mm),将测试样品粘贴在不锈钢板上的双面胶上,用2000g压辊在其表面来回滚压三次(300mm/min)。将测试样品180度弯折,手动将测试样品的有机-无机混合层与基膜剥开25mm,将该测试样品固定在试验机上(例如INSTRON 336),使剥离面与试验机力线保持一致,试验机以30mm/min连续剥离,得到的剥离力曲线,取平稳断的均值作为剥离力F0,则通过以下公式算出测试样品中有机-无机混合层与集流体之间的粘结力F。F=F0/测试样品的宽度(F的计量单位:N/m)。
2、隔离膜透气度测试
使用Gurley法测量隔离膜透气度,测试仪器为美国Gurley4110透气度仪。将隔膜平展,选取平整无油污的位置,放置在空气压缩筒出气口,旋紧固定,隔离膜固定在工位后,利用圆筒的自身重力来压缩筒内空气。随着空气通过试样,圆筒便会平稳下落。测量100CC的空气通过6.45cm 2试样所需的时间,即为透气度。
3、中值粒径的测试
取一洁净烧杯,加入适量待测样品,滴加表面活性剂后添加分散剂,超声120W/5min确保样品在分散剂中完全分散。测试仪器为美国马尔文2000。样品倒入进样塔后随溶液循环到测试光路系统,颗粒在激光束的照射下,通过接受和测量散向光的能量分布就可以得出颗粒的粒度分布特征(遮光度:8-12%)。根据测试数据绘制粒径质量分布图和粒径数量分布图。从该分布图中得到:占总质量50%的颗粒直径大于某D值,另有占总质量50%的颗粒直径小于此D值,则此D值为颗粒的中值粒径。
4、基膜和涂层厚度的测试方法
将基膜平展,放置于在水平面上,对折N次后使用万分尺(例如Mitutoyo数显万分尺)测量多次,设总厚度为Da,则单层基膜厚度d=Da/2N。涂层厚度测量方法同理,计算公式:d1=(Db-Da)/2N,其中Db为带有涂层的隔离膜的总厚度。
【电池相关参数测试】
1、60℃存储100天电池内部电解液中Mn 2+浓度
以沉积在负极Mn 2+浓度为准。拆解电池后取出负极极片,用DMC溶液浸泡半小时洗去表面残留的电解液,随后将极片晾干。取适量极片,称重后用王水进行消解,过滤后得到溶液。随后用赛默飞7000测试仪测量出溶液中Mn 2+浓度。例如,本申请实施例的Mn 2+浓度是取0.5g负极极片,用50ml王水消解,过滤后测得的浓度,所述王水由质量分数36%的浓盐酸和质量分数68%浓硝酸按照体积比为3:1的比例混合。
2、循环1000次后放电直流内阻(DCR,Directive Current  Resistance)测试
在25℃下,将实施例和对比例对应的电池,以0.5C恒流充电至4.25V,再以4.25V恒定电压充电至电流为0.05C,搁置10min后,再以0.5C恒流放电至2.8V,此时放电容量记为初始容量C 0,随后循环1000圈。将上述电池再以0.5C恒流充电至4.25V,再以4.25V恒定电压充电至电流为0.05C,搁置10min后,0.5C恒流放电30s,测量此时的DCR。
3、60℃存储性能测试
在25℃下,将实施例和对比例对应的电池,以0.5C恒流充电至4.25V,再以4.25V恒定电压充电至电流为0.05C,搁置5min后,再以0.5C恒流放电至2.8V,此时放电容量记为初始容量C 0
将上述电池再以0.5C恒流充电至4.25V,再以4.25V恒定电压充电至电流为0.05C,之后将该电池放入60℃的恒温箱,储存100天后取出。将取出的电池放置于25℃大气环境下,待锂离子电池温度完全降至25℃后,对锂离子电池以0.5C恒流放电至2.8V,再以0.5C恒流充电至4.25V,最后再将锂离子电池以0.5V恒流放电至2.8V,此时的放电容量为C1,则存储100天后电池的高温可逆容量保持率M=C1/C 0×100%。
表1 隔离膜以及电池的相关性能参数
Figure PCTCN2021112255-appb-000004
Figure PCTCN2021112255-appb-000005
根据表1可知,实施例1-1~1-13的锂离子电池在负极沉积的锰离子的浓度显著低于对比例C1~C4,锂离子电池的存储性能和功率性能也优于对比例C1~C4。
通过比较实施例1-3和实施例1-7~1-9可知,当D2/D1为定值时,当使用不同种类第一无机颗粒时,锂离子电池具有都具有良好的存储性能和功率性能,并且差异不显著。
通过比较实施例1-3和实施例1-9可知,当D2/D1为定值时,第一无机颗粒与第二无机颗粒种类是否相同对锂离子电池存储性能和功率性能影响不显著。
通过比较实施例1-3和实施例1-10~1-11可知,当D2/D1为定值时,有机粘结质的种类对锂离子电池储性能和功率性能影响不显著。
通过综合比较实施例1-1~1-6和对比例C3~C4可知,当D2/D1小于2或大于55时,锂离子电池在负极沉积的锰离子的浓度显著提高,锂离子电池的存储性能和功率性能均明显降低。
表2 隔离膜以及电池的相关性能参数表
Figure PCTCN2021112255-appb-000006
根据表2,综合比较实施例2-1~2-7可知,在D2/D1相同的前提下,当m1/m2在0.5~4.0范围内时,锂离子电池负极沉积的锰离子的浓度较低,存储性能和功率性能更优。
表3 隔离膜以及电池的相关性能参数表
Figure PCTCN2021112255-appb-000007
根据表3,综合比较实施例3-1~3-7可知,在D2/D1基本一致的前提下,当A1/A2在0.1~25范围内时,锂离子电池负极沉积的锰离子的浓度较低,存储性能和功率性能更优;相比于实施例3-1,粘结力也较大。
表4 隔离膜以及电池的相关性能参数表
Figure PCTCN2021112255-appb-000008
根据表4,综合比较实施例4-1~4-7可知,在D2/D1基本一致的 前提下,随着d1/d的增加,锂离子电池负极沉积的锰离子的浓度降低,但是对应透气度增加,从锂离子电池存储性能来看,当d1/d的值位于20%~50%范围内时,锂离子电池的存储性能最优。
表5 隔离膜以及电池的相关性能参数表
Figure PCTCN2021112255-appb-000009
根据表5,综合比较实施例5-1~5-5,在D2/D1基本一致的前提下,随着正面涂覆区与正面空白区的面积之比、反面涂覆区与反面空白区的面积之比的增加,锂离子电池负极沉积的锰离子的浓度降低,但是对应透气度变差。从锂离子电池存储性能来看,当正面涂覆区与正面空白区的面积之比在1:1~3:1、反面涂覆区与反面空白区的面积之比在0.5:1~1:1范围内时,锂离子电池的存储性能最优,功率性能也在较优范围内。
表6 隔离膜以及电池的相关性能参数表
Figure PCTCN2021112255-appb-000010
根据表6,综合实施例6-1~6-4,“正面的有机-无机混合层中无机颗粒的质量含量不小于所述基膜反面的有机-无机混合层中无机颗粒的质量含量”对降低过渡金属离子量改善更有效,并且能够同时兼顾较好的隔离膜的透气度,锂离子电池兼具良好的存储性能和功率性能。

Claims (17)

  1. 一种隔离膜,其特征在于,
    包括基膜和位于所述基膜至少一个表面的有机-无机混合层,所述有机-无机混合层包括无机颗粒和有机粘结质;
    所述无机颗粒由中值粒径在微米级的第一无机颗粒和中值粒径在纳米级的第二无机颗粒组成,所述第一无机颗粒以μm计的中值粒径数值D1与所述第二无机颗粒以nm计的中值粒径数值D2之比满足2≤D2/D1≤55,并且,所述第一无机颗粒或所述第二无机颗粒选自(SiO x)(H 2O) y、(M c+) b(SiO z) a-
    其中,0≤x≤2,0≤y≤2且y为整数;z=3或4,a=2或4,b×c=a;M可以为锂、钠、钾、镁、钙、铝中的一种或多种。
  2. 根据权利要求1所述的隔离膜,其特征在于,
    部分所述第一无机颗粒和/或所述第二无机颗粒凸出于所述有机-无机混合层表面。
  3. 根据权利要求1或2所述的隔离膜,其特征在于,
    所述第一无机颗粒的以μm计的中值粒径数值D1为1~5,所述第二无机颗粒以nm计的中值粒径数值D2为10~55。
  4. 根据权利要求1-3中任一项所述的隔离膜,其特征在于,
    所述有机粘结质为含有羟基和/或羧基的羧酸的碱金属盐、含有羟基和/或羧基的磺酸的碱金属盐中的一种以上,进一步可选为羧甲基纤维素钠(CMC-Na)、聚丙烯酸钠(PAA-Na)、聚苯乙烯磺酸钠(PSS-Na)、海藻酸钠(SA)中的一种以上。
  5. 根据权利要求1-4中任一项所述的隔离膜,其特征在于,
    所述无机颗粒为Si、SiO 2、H 2SiO 3、H 4SiO 4、K 2SiO 3、K 4SiO 4和Na 4SiO 4中的一种或多种;可选地,
    所述第一无机颗粒可选为Si、SiO 2、H 2SiO 3、H 4SiO 4、K 2SiO 3、K 4SiO 4和Na 4SiO 4中的一种以上,所述第二无机颗粒可选为SiO 2和/或K 2SiO 3
  6. 根据权利要求1-5中任一项所述的隔离膜,其特征在于,
    在所述有机-无机混合层中,所述第一无机颗粒质量m1与所述第二无机颗粒的质量m2满足0.5≤m1/m2≤4。
  7. 根据权利要求1-6中任一项所述的隔离膜,其特征在于,
    所述有机-无机混合层中,所述有机粘结质质量含量A1和所述无机颗粒的质量含量A2之比A1/A2为0.1~25:100。
  8. 根据权利要求1-7中任一项所述的隔离膜,其特征在于,
    所述有机-无机混合层中,所述无机颗粒的质量含量为80%-99.9%,所述有机粘结质的质量含量为0.1%-20%,以所述有机-无机混合层的总质量计。
  9. 根据权利要求1-8中任一项所述的隔离膜,其特征在于,
    所述有机-无机混合层的厚度d1占所述隔离膜总厚度d的20%-50%,隔离膜总厚度d为6-25μm。
  10. 根据权利要求1-9中任一项所述的隔离膜,其特征在于,
    所述基膜正面包括正面涂覆区和正面空白区,所述正面涂覆区与所述正面空白区的面积之比为1~3:1;
    所述基膜反面包括反面涂覆区和反面空白区,所述反面涂覆区与所述反面空白区的面积之比为0.5~1:1,所述正面涂覆区与所述反面涂覆区表面涂有所述有机-无机混合层。
  11. 根据权利要求1-10中任一项所述的隔离膜,其特征在于,
    所述基膜的正反面分别涂有所述有机-无机混合层,所述基膜正面的有机-无机混合层中无机颗粒的质量含量不小于所述基膜反面的有机-无机混合层中无机颗粒的质量含量;所述基膜正面的有机-无机混合层与正极相接触,所述基膜反面的有机-无机混合层与负极相接触。
  12. 根据权利要求1-11中任一项所述的隔离膜,其特征在于,
    所述正面空白区与所述反面涂覆区的正投影重合,所述反面空白区与所述正面涂覆区的正投影重合,所述正面涂覆区与所述反面涂覆区表面涂有所述有机-无机混合层。
  13. 根据权利要求1-12中任一项所述的隔离膜,其特征在于,
    所述隔离膜的热收缩率比所述基膜热收缩率少70%~75%。
  14. 一种锂离子电池,其特征在于,包括权利要求1-13中任一项所述的锂离子电池。
  15. 一种电池模块,其特征在于,包括权利要求14中任一项所述的锂离子电池。
  16. 一种电池包,其特征在于,包括权利要求14所述的锂离子电池或权利要求15所述的电池模块中的一种以上。
  17. 一种用电装置,其特征在于,
    包括权利要求14所述的锂离子电池、权利要求15所述的电池模块或权利要求16所述的电池包中的一种以上,所述锂离子电池或所述电池模组或所述电池包用作所述用电装置的电源或所述用电装置的能量存储单元。
PCT/CN2021/112255 2021-08-12 2021-08-12 隔离膜、锂离子电池、电池模块、电池包和用电装置 WO2023015521A1 (zh)

Priority Applications (6)

Application Number Priority Date Filing Date Title
EP21936240.7A EP4160767A4 (en) 2021-08-12 2021-08-12 SEPARATOR, LITHIUM-ION BATTERY, BATTERY MODULE, BATTERY PACK AND POWER CONSUMPTION DEVICE
KR1020227036435A KR20230025382A (ko) 2021-08-12 2021-08-12 세퍼레이터, 리튬 이온 전지, 전지 모듈, 전지 팩 및 전기 장치
JP2022563084A JP2023539970A (ja) 2021-08-12 2021-08-12 セパレータ、リチウムイオン電池、電池モジュール、電池パック及び電力消費装置
PCT/CN2021/112255 WO2023015521A1 (zh) 2021-08-12 2021-08-12 隔离膜、锂离子电池、电池模块、电池包和用电装置
CN202180083358.3A CN116601817A (zh) 2021-08-12 2021-08-12 隔离膜、锂离子电池、电池模块、电池包和用电装置
US18/087,713 US20230127767A1 (en) 2021-08-12 2022-12-22 Separator, lithium-ion battery, battery module, battery pack, and electrical device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/CN2021/112255 WO2023015521A1 (zh) 2021-08-12 2021-08-12 隔离膜、锂离子电池、电池模块、电池包和用电装置

Related Child Applications (1)

Application Number Title Priority Date Filing Date
US18/087,713 Continuation US20230127767A1 (en) 2021-08-12 2022-12-22 Separator, lithium-ion battery, battery module, battery pack, and electrical device

Publications (1)

Publication Number Publication Date
WO2023015521A1 true WO2023015521A1 (zh) 2023-02-16

Family

ID=85199766

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2021/112255 WO2023015521A1 (zh) 2021-08-12 2021-08-12 隔离膜、锂离子电池、电池模块、电池包和用电装置

Country Status (6)

Country Link
US (1) US20230127767A1 (zh)
EP (1) EP4160767A4 (zh)
JP (1) JP2023539970A (zh)
KR (1) KR20230025382A (zh)
CN (1) CN116601817A (zh)
WO (1) WO2023015521A1 (zh)

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5389433A (en) * 1993-04-01 1995-02-14 W. R. Grace & Co.-Conn. Battery separator
CN102468466A (zh) * 2010-11-17 2012-05-23 索尼公司 耐热微孔膜和电池隔膜
CN103811702A (zh) * 2014-02-12 2014-05-21 佛山市金辉高科光电材料有限公司 一种新型陶瓷涂层聚烯烃复合膜及其制备方法
CN104064707A (zh) * 2014-06-09 2014-09-24 东莞市魔方新能源科技有限公司 无机/有机复合隔膜、其制备方法及含该隔膜的锂离子二次电池
CN106463675A (zh) * 2014-06-27 2017-02-22 日本瑞翁株式会社 非水系二次电池功能层用组合物、非水系二次电池用功能层和非水系二次电池
CN107452925A (zh) * 2016-04-14 2017-12-08 三星Sdi株式会社 多孔耐热层组合物、隔膜及使用隔膜的电化学电池
CN113067098A (zh) * 2021-03-19 2021-07-02 江苏厚生新能源科技有限公司 一种高强度,高能量密度latp复合膜的制备方法

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR102312278B1 (ko) * 2018-12-21 2021-10-12 삼성에스디아이 주식회사 리튬 이차 전지용 분리막 및 이를 포함하는 리튬 이차 전지

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5389433A (en) * 1993-04-01 1995-02-14 W. R. Grace & Co.-Conn. Battery separator
CN102468466A (zh) * 2010-11-17 2012-05-23 索尼公司 耐热微孔膜和电池隔膜
CN103811702A (zh) * 2014-02-12 2014-05-21 佛山市金辉高科光电材料有限公司 一种新型陶瓷涂层聚烯烃复合膜及其制备方法
CN104064707A (zh) * 2014-06-09 2014-09-24 东莞市魔方新能源科技有限公司 无机/有机复合隔膜、其制备方法及含该隔膜的锂离子二次电池
CN106463675A (zh) * 2014-06-27 2017-02-22 日本瑞翁株式会社 非水系二次电池功能层用组合物、非水系二次电池用功能层和非水系二次电池
CN107452925A (zh) * 2016-04-14 2017-12-08 三星Sdi株式会社 多孔耐热层组合物、隔膜及使用隔膜的电化学电池
CN113067098A (zh) * 2021-03-19 2021-07-02 江苏厚生新能源科技有限公司 一种高强度,高能量密度latp复合膜的制备方法

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
CAS, no. 25704-18-1

Also Published As

Publication number Publication date
EP4160767A4 (en) 2023-10-18
US20230127767A1 (en) 2023-04-27
KR20230025382A (ko) 2023-02-21
JP2023539970A (ja) 2023-09-21
EP4160767A1 (en) 2023-04-05
CN116601817A (zh) 2023-08-15

Similar Documents

Publication Publication Date Title
WO2023093340A1 (zh) 一种外包装及其制备方法、二次电池、电池模块、电池包
WO2023029002A1 (zh) 负极集流体、含有其的二次电池、电池模块、电池包及用电装置
WO2024012166A1 (zh) 二次电池及用电装置
WO2023124913A1 (zh) 负极活性材料、其制备方法及其相关的二次电池和装置
WO2023082924A1 (zh) 极片、锂离子电池、电池模块、电池包及用电装置
WO2023082925A1 (zh) 一种正极材料、正极极片、二次电池、电池模块、电池包及用电装置
WO2023060529A1 (zh) 锂离子电池
WO2023137624A1 (zh) 二次电池、电池模块、电池包以及用电装置
WO2023108352A1 (zh) 一种正极活性材料及其相关的极片、二次电池、电池模块、电池包和装置
WO2023077516A1 (zh) 负极极片及其制备方法、二次电池、电池模块、电池包及用电装置
WO2023087218A1 (zh) 负极极片及其制备方法、二次电池、电池模块、电池包和用电装置
WO2023044866A1 (zh) 硅碳负极材料、负极极片、二次电池、电池模块、电池包和用电装置
WO2023283960A1 (zh) 正极极片、二次电池及其制备方法与包含该二次电池的电池模块、电池包和用电装置
WO2023015521A1 (zh) 隔离膜、锂离子电池、电池模块、电池包和用电装置
WO2023133844A1 (zh) 正极极片、二次电池、电池模块、电池包和用电装置
WO2023133881A1 (zh) 正极极片、二次电池、电池模块、电池包和用电装置
WO2023060587A1 (zh) 负极极片、二次电池、电池模块、电池包及用电装置
WO2024098171A1 (zh) 电芯及其制备方法、二次电池和用电装置
WO2023174012A1 (zh) 正极极片、锂离子二次电池、电池模块、电池包和用电装置
WO2023133882A1 (zh) 隔膜及其相关的二次电池、电池模块、电池包和用电装置
WO2023109363A1 (zh) 一种正极极片、二次电池、电池模块、电池包和用电装置
WO2023124645A1 (zh) 正极活性材料、制备正极材料的方法、正极极片、二次电池、电池模块、电池包和用电装置
WO2024065165A1 (zh) 粘结剂和包含其的隔离膜
WO2023130976A1 (zh) 正极极片、二次电池、电池模块、电池包和用电装置
WO2023070548A1 (zh) 电池集流体及其制备方法、二次电池、电池模块、电池包和用电装置

Legal Events

Date Code Title Description
ENP Entry into the national phase

Ref document number: 2022563084

Country of ref document: JP

Kind code of ref document: A

ENP Entry into the national phase

Ref document number: 2021936240

Country of ref document: EP

Effective date: 20221017

WWE Wipo information: entry into national phase

Ref document number: 202180083358.3

Country of ref document: CN

NENP Non-entry into the national phase

Ref country code: DE