TWI475741B - Separator substrate, electrochemical cell including separator, and method for fabricating separator - Google Patents

Description

Isolation membrane, electrochemical cell including separator and preparation method of separator

The present invention relates to a composite material and a method of preparing and using the same, in particular to a mixed material having a polymer material and ion nano particles, and a different application of the mixed material, such as in a battery and an electrochemical battery. .

In many applications, the need to use a single, monolithic material is expensive, difficult, and difficult to achieve. For example, specific applications require the chemical and/or thermal stability of ceramic materials, as well as the mechanical elasticity of some polymeric materials and the processing of specific types (eg, extrusion, spin-coating). Easy processing. In this case, a composite and/or hybrid material composed of two or more different kinds of materials may be used. The examples used span many different fields and applications, including electrochemical cells, space engineering, and armor.

The following description is exemplified without limiting the scope of the present disclosure. An example of a mixed material application is a battery separator or a separator used in an electrochemical cell. The battery or electrochemical cell separator must be able to isolate the electrode and still maintain a sufficient level of ionic conductivity. The separator may be an insulating material that is thin, porous, and has good mechanical strength. Polymer separators are often used mainly because of their high mechanical strength and are easily prepared by some processing techniques, which can make them highly porous. Examples of polymer materials commonly used in battery separators include organic polyolefins and composite materials (e.g., polypropylene/polyethylene/polypropylene). However, some conventional polymer materials lack thermal stability, chemical stability, or both. These characteristics make them unsuitable for certain applications, such as exposure to highly corrosive chemical environments or high temperature environments, one or both of which may occur in high performance batteries. Therefore, high-performance batteries tend to use inorganic separators (such as glass and ceramic separators), inorganic separators are compatible with their corrosive and non-polymer electrolytes; and some inorganic separators are brittle or difficult to process. And so on.

Fig. 1A illustrates a ceramic/polymer composite material 1 as a conventional battery separator material. As shown in FIG. 1A, the substrate 2, which is generally a polymer, is functionalized with an oxide group 4. Substrate 2 can be porous, thus increasing the surface area available for ion exchange. Surface functionalization 4 allows the surface of the substrate 2 to be coated with a layer of material 6, thereby improving properties such as thermal and chemical stability and wettability. The effect of the use of electrolytes in battery applications on wettability is particularly noticeable because low electrolyte wettability separators can reduce or reduce battery efficiency. In many examples, material 6 can comprise a plurality of particles 6a, wherein particles 6a can comprise ceramic, glass, and/or metal oxide components. The particles may be deposited on the substrate 2 in several ways, such as Sol-gel processing or wet deposition. Usually, in order to maintain the integrity of the material 6, an adhesive 6b must be applied to adhere the particles 6a to each other. In order to fix or retain the material 6 on the surface, it is also necessary to heat the material 6 to a temperature sufficient to sinter the ceramic particles 6a. Sintering may cause chemical bonding between some of the particles 6a and other particles 6a or with the adhesive 6b. By way of example, sintering will activate the chemical cross-linking between the particles 6a-adhesive 6b-particles 6a and/or particles 6a-adhesive 6b-substrate 6. In some instances, sintering may even cause partial or complete fusion of particles 6a. Moreover, the high heat of the sintering process lowers the quality of the substrate 2. Furthermore, the use of adhesive 6b has significant disadvantages, including congenitally limiting the density of particles 6a and the use of chemical agents that degrade under harsh chemical environments within electrochemical cells.

Figure 1B is an electron micrograph of an exemplary substrate. Figure 1B is a paper "S review on the separators of liquid electrolyte Li-ion batteries," Journal of Power Sources, Volume 164, Issue 1, 2007, page 351, by S. S. Zhang et al. Reprinted. Figure 1B shows a nonwoven substrate 15a. In particular, FIG. 1B illustrates a top view image of the nonwoven substrate 15b before the addition of the particles 6a. Figure 1B illustrates a nonwoven substrate 15b having a plurality of fibers 15a.

1C shows a top view of a ceramic/non-woven release film 600 in which a coating 630 having microparticles, metal oxides, and an adhesive is formed on the surface of a commercially available nonwoven substrate. Figure 1C is a paper "S review on the separators of liquid electrolyte Li-ion batteries," Journal of Power Sources, Volume 164, Issue 1, 2007, page 351. Reprinted. FIG. 1C illustrates a plurality of metal oxide particles 614 and an adhesive 616 between the particles 614.

In each of these examples, the protective ceramic layer is quite thick (several microns). Moreover, in some applications or processes, the protective layer is formed using an adhesive and/or high temperature sintering which degrades or limits the properties of the substrate, protective layer or both. In either case, the chemical and thermal stability of the composite or hybrid material is affected.

In one embodiment, the present disclosure is directed to a barrier film comprising a substrate, wherein the substrate has a body portion and a surface portion. The surface portion has at least one porous region, and the at least one porous region has a net charge; and the plurality of ion particles are coupled to at least a portion of the porous region, wherein a portion of the ionic particles have a porous region The net charge is opposite to one of the net charges. In some variations of this embodiment, the other ionic particles may have the same net charge as the net charge of the porous region. The coupling of at least a portion of the porous region and the ionic particles provides the barrier substrate with at least one of electrochemical performance, chemical stability, hygroscopicity, thermal stability, and toughness.

In another embodiment, the present disclosure is directed to an electrochemical cell that includes a separator. The separator includes a substrate having a body portion and a surface portion. A coating covers at least a portion of the surface portion. At least a portion of the surface portion is porous. The cladding ion is bonded to the at least a portion of the surface portion. The coupling of at least a portion of the porous region and the ionic particles provides the barrier substrate with at least one of enhanced electrochemical performance, chemical stability, thermal stability, interface compatibility, and toughness.

In another embodiment, the present disclosure is directed to a method of making a barrier film. The method includes processing a substrate such that a surface portion of the substrate has a net charge; and coupling the plurality of ion particles to at least a portion of the surface portion. The ionic particles have a net charge that is opposite to the net charge of the surface portion. The coupling of the ionic particles to at least a portion of the surface portion provides the separator with characteristics of at least one of electrochemical performance, chemical stability, thermal stability, hygroscopicity, and toughness.

2A through 2C illustrate an isolation membrane structure and combination using one of the ionic particles in accordance with an embodiment of the present invention. FIG. 2A illustrates one exemplary substrate 10 prior to processing. 2B illustrates a substrate 10 after an exemplary surface treatment in which surface treatment causes one surface region 10a of the substrate 10 to be negatively charged. Figure 2C illustrates substrate 10 after contact with an oppositely charged ionic material. Although FIG. 2B shows the negatively charged substrate 10, this is merely an example. As described below, this process can be performed in different ways, such as using a positively charged substrate 10 and negatively charged ionic particles 14.

FIG. 2A illustrates a substrate 10. As shown, the substrate 10 is non-conductive such that it retains the surface charge 12 in its surface region 10a or portion of the surface region 10a. However, in some embodiments, substrate 10 can have conductive portions and/or thermally conductive portions. Substrate 10 can comprise several materials that are used in different applications. For example, substrate 10 can comprise polymeric materials such as: organic polyolefins, and composite materials (eg, polypropylene/polyethylene/polypropylene), and other materials commonly used in electrochemical cells (eg, Cellulose, polyvinyl chloride (PVC), polyethylene terephthalate (PET), polyvinylidene fluoride (PVDF). The substrate 10 may also comprise other kinds of polymer materials and/or composite materials including, but not limited to, polypropylene, fluoropolymers such as polyvinylidene fluoride, and the like. Molecular material. In addition to the polymeric material, the substrate 10 can be or comprise one of a composition of inorganic, metallic or other organic materials, a combination of the foregoing materials, or a combination of both.

Substrate 10 can comprise a porous or substantially porous region. For example, the substrate 10 may include pores that pass through its bulk 10b and surface area 10a. Further, the surface area 10a and/or the body 10b of the upper portion of the substrate 10 may have a substantially porous structure, while the surface area 10a of the other substrate 10 and/or portions of the body 10b are absent. By way of example, portions of surface area 10a and/or body 10b of substrate 10 lack or have fewer pores to maintain structural integrity. If the substrate 10 is used in a harsh chemical environment, portions of the surface region 10a of the substrate 10 and/or portions of the body 10b may have no pores, thereby protecting portions of the substrate 10 and/or other components from being affected. The effects of surrounding chemicals (eg, electrolytes in electrochemical cells). In these and other applications, substrate 10 can comprise porous and non-porous regions and/or other porous varying structures.

The cylindrically shaped substrate 10 illustrated in Figure 2A is merely exemplary. Substrate 10 can have different shapes on different barrier films or in other applications. For example, the substrate 10 can be shaped as a rectangular column and/or have a length-to-width ratio (i.e., wall-shaped) that is significantly longer on one side than the other sides. The substrate 10 can also maintain its tubular or elongated shape, but with one of several different cross-sectional shapes (eg, square, circular, triangular, various trapezoids, etc.). The substrate 10 can also be fabricated to include regular or irregular shapes. For example, substrate 10 can comprise a plurality of cross-ply fibers that can result in regular or irregular shapes. Substrate 10 may alternatively have irregularities or other shapes suitable for a particular application.

2D shows an electron micrograph of an exemplary substrate, which is a microporous polymer substrate 15c that can be used in conjunction with the present disclosure. It should be noted that the conventional substrate 15b illustrated in FIG. 1B can also be used in conjunction with the present invention. Specifically, Fig. 2D shows a top view image of a microporous polymer substrate 15c in which the microporous polymer substrate 15c is in a state before the ion particles are added. Fig. 2D shows a microporous polymer substrate 15c having pores 15d.

Figure 2B illustrates substrate 10 after treatment prior to the addition of ionic particles. In general, the treatment involves surface treatment of the surface region 10a of the substrate 10. In the illustrated embodiment, as shown in Figure 2B, the process causes the surface 10a of at least one region to carry a net charge. By way of example, processing can cause the entire surface region 10a to be negatively charged, as shown by the negative charge 12 on the surface region 10a. The treatment may not require the entire surface area 10a to be charged with a net charge, and advantageously, in some applications, the treatment will have a fractional surface area 10a with a net charge. In some instances, it may be advantageous to perform the surface treatment on a particular pattern (e.g., some tangible feature or shape on surface area 10a). For example, the recess on the surface region 10a can impart a net surface charge. Some techniques can be used to create a particular net charge pattern in surface area 10a, including, for example, lithography. In fact, some lithography techniques may allow for the size, location, geometry, number, etc. of the treated or charged portions to be planned on the surface region 10a.

The treatment method applied to the surface region 10a of the substrate 10 in this embodiment is one or more of several methods for charging the surface region 10a. An example of this involves exposing surface area 10a to high energy processing, such as exposing surface area 10a to plasma. The plasma treatment can form charged surface groups without sacrificing or substantially altering the bulk properties of the substrate 10. The plasma treatment can comprise any suitable plasma produced by any suitable parameters. By way of example, substrate 10 can be treated with a microwave oxygen plasma for 5 minutes at room temperature at 50 watts. The plasma parameters can be adjusted to the desired or required surface net charge. The plasma treatment may or may not be performed over a surface area 10a of the substrate 10. For example, the substrate 10 comprising polypropylene may be irradiated with ultraviolet plasma to produce a surface group with a net charge 12 on the surface of the substrate 10. The net charge 12 can be positive, negative, or a combination of both (ie, changing or modifying the plasma parameters when the surface regions 10a of different locations are exposed to the plasma, such that different bands can be produced on different portions of the surface region 10a Surface group of charge).

The treatment method may also include one of several other treatment methods, including chemical treatment, ultraviolet irradiation, and the like. In some instances, it may be appropriate to deposit a charge group from a solution, vacuum or gaseous environment on the surface. Any suitable method of rendering a portion of the surface region 10a with a net charge is within the scope of the present disclosure.

The net surface charge 12 can be negative (as shown in Figure 2B) or positive in other embodiments. The net surface charge 12 need not be the same throughout the entire surface area 10a. By way of example, in some applications, some portions of surface region 10a have a negative surface charge, while other portions of surface region 10a have a positive surface charge. In some examples, the overall surface charge distribution of the entire surface region 10a is electrically neutral.

Fig. 2C illustrates the addition of ionic particles 14 to the surface region 10a after the treatment shown in Fig. 2B. In general, the ionic particles 14 themselves carry a net surface charge 16. The net surface charge 16 of the ionic particles 14 is opposite to the electrical conductivity of the net surface charge 12 on the partial surface region 10a. In this case, the ionic particles 14 are attracted to portions of the surface region 10a because the net surface charge 12 is electrically opposite to the net surface charge 16 of the ionic particles 14. Although FIG. 2C illustrates that the ionic particles 14 have a positive net surface charge 16, this is merely illustrative. In other configurations, the net surface charge 16 of the ionic particles 14 can be negative. In still other configurations, some of the ionic particles 14 may have a positive surface charge while the other ionic particles 14 have a negative surface charge. The amount of charge between the ionic particles 14 can vary.

In some variant embodiments, it is advantageous for the ionic particles 14 to have a uniform net surface charge 16. These embodiments may include applications that require uniform or near uniform coverage. Other applications may require bimodal, trimodal or multimodal distributions with different requirements for net surface charge. For example, in some variations, it may be advantageous to have some of the ionic particles 14 with a particularly low static charge attached to the surface region 10a that are not flat (e.g., recesses and/or pores). In these and other variations, some of the ionic particles 14 with a particularly low electrostatic charge are applied over the other surface portions of the surface region 10a. In still other variations, a plurality of groups of ionic particles 14 having different net surface charges can be used to produce similar or additional effects.

The ionic particles 14 can be of different sizes. In one embodiment, the ionic particles 14 are of the nanometer scale. For example, they may range in diameter from about 1 nanometer to 500 nanometers. In another embodiment, the ionic particles 14 can have a diameter of between about 10 nanometers and 30 nanometers. In still other embodiments, some of the ionic particles 14 can have a diameter greater than tens of micrometers. The particle size distribution of the ionic particles 14 can be small, and the ionic particles 14 can be substantially monodisperse as shown in Figure 2C. In other variations, the ionic particles 14 may have a particularly large particle size distribution, and even the particle size distribution may contain diameter variations of orders of magnitude. These and other applications may have bimodal, trimodal or multimodal ion particle 14 particle size distributions to suit a particular application. By way of example, larger ionic particles 14 may have a certain net surface charge 16, while smaller ionic particles 14 may have the same or different net surface charges 16. Ion particles 14 having a bimodal, trimodal or multimodal particle size distribution that are sized to be associated with a net surface charge 16. For example, the larger ionic particles 14 have more net surface charge 16 . However, particles constituting a bimodal, trimodal or multimodal particle size distribution may be ionic particles 14 having the same net surface charge 16.

Although FIG. 2C shows the ionic particles 14 in a spherical shape, this is merely an illustrative example. The ionic particles 14 may have suitable shapes in the context of the present invention, including various geometric shapes, circles, partial circles, or incomplete shapes. The ionic particles 14 may be microcrystals of a fairly regular shape or may be partially crystalline and/or non-crystalline. The ionic particles 14 may have a full or partial irregular shape and may be elongated, flat or have any suitable shape.

The ionic particles 14 can be attracted to portions of the surface region 10a due to the net surface charge 12 being electrically opposite to the net surface charge 16 of the ionic particles 14. This attraction, in some instances, results in an ionic bond between the ionic particles 14 and the portion of the surface region 10a having an opposite net charge 12. In some instances, if the strength of the ionic bond is sufficient, the process produces a coated substrate 100 as shown in Figure 2C. In particular, ionic bonding occurs between the ionic particles 14 and the portion of the surface region 10a having an opposite net charge 12, and the ionic bonding results in a surface layer 18 formed by the ionic particles 14. Formed, the surface layer 18 covers at least a portion of the surface area 10a. In some variations, the ionic particle surface layer 18 is preferred to cover the entire surface area 10a. In other applications, the surface layer 18 preferably covers only a portion of the surface area 10a.

3A-1 and 3A-2 show schematic representations of the synthesis of ionic particles, particularly ionic particles, in accordance with an embodiment of the present invention. 3B is a close-up, cross-sectional view of one of the ionic particles synthesized according to the synthesis method of FIG. 3A-1 in accordance with one embodiment of the present disclosure. The core 14a (Figs. 3A and 3B) of the ionic particles 14 may comprise an inorganic material such as a metal oxide. Figures 3A-3 and 3A-4 disclose several polymer electrolytes that are coupled to the synthesis technique of Figure 3A-2 and successfully implemented in the present case.

The present disclosure is not particularly limited to the above-described disclosed core 14a. Any core made of chemically stable and chemically resistant materials can be used. By way of example, metal oxides are chemically stable in a particular environment and are therefore suitable for use in making the core 14a. This environment can include lithium, electrolytes and their electrolyte additives. Since the lithium and lithium-containing compounds in the hybrid material are suitable for some lithium ion battery applications, the use of these cores 14a improves chemical stability. Examples of suitable metal oxides for making the core 14a include, but are not limited to, cerium oxide (SiO ₂ ), zinc oxide (ZnO), tin dioxide (SnO ₂ ), titanium dioxide (TiO 2 ), zirconia (ZrO 2 ), Alumina (Al 2 O 3 ), barium titanate (BaTiO 3 ), yttrium oxide (Y 2 O 3 ), magnesium oxide (MgO), nickel oxide (NiO), calcium oxide (CaO). Further, an oxide or other material in the form of a hollow sphere may be used as the core 14a. The core 14a may also be or include other types of inorganic materials such as ceramics, glass, tantalum and/or metals. The core 14a may also be made of or entirely made of an organic material or a carbon-based material. The core 14a can be made of any suitable technique suitable for use in the present case. For example, the core 14a may be a precipitation technique, a sol-gel technique or a microemulsion or a nanoemulsion technique. The core 14a may be inorganic nanocrystals or other nanocrystals produced by sintering or other processes. A core 14a made of a thermally stable material can also be used. For example, in some applications, thermal stability above 150 °C is helpful. Suitable cores 14a of this thermal stability comprise any of the aforementioned cores 14a, as well as other materials having suitable thermal stability, including organic or inorganic. By way of example, a metal oxide core 14a will be selected for its higher thermal stability due to its higher molecular material or other substrate 10. In this and other examples, one of the ionic particle surface layers 30 formed of ionic particles 14 having an exemplary metal oxide core 14a can improve the overall thermal stability of the entire separator substrate 100. In some applications, it is beneficial to use a core 14a having a higher wettability than the substrate 10. In other words, the use of a core 14a made of one of the above metal oxides, other materials discussed herein, or other hidden materials can improve the wettability of the separator 100 to the electrolyte, wherein the substrate 10 is made of the same material. The electrolyte has low wettability. For example, a metal oxide core 14a is selected because it has a higher electrolyte wettability than the polymer substrate 10. In this and other examples, the ionic particle layer 30, which is composed of the ionic particles 14 of the core 14a made of a metal oxide, improves the overall wettability of the entire separator 100.

In some applications, it is also beneficial to use a core 14a that is mechanically stable compared to the substrate 10. In other words, the use of the core 14a made of one of the above metal oxides, other materials discussed herein, or other hidden materials can improve the mechanical toughness of the separator 100, wherein the substrate 10 is made of a lower material. Mechanical stability. For example, a metal oxide core 14a is selected because it has a higher mechanical stability than the polymer substrate 10. In this and other examples, one of the ionic particle layers 30 composed of the ionic particles 14 having the metal oxide core 14a improves the mechanical toughness of the entire separator 100. In many instances, it is also advantageous to use a substantially insulating or non-conductive core 14a to avoid or reduce shorting through the interior of the ionic particles 14, wherein the material of the insulating or non-conductive core 14a can be a metal oxide. In some applications, the core 14a is also wet, especially for the wettability of the electrolyte. In other words, the use of a core 14a made of one of the above metal oxides, other materials discussed herein, or other hidden materials, can improve the electrolyte wettability of the separator 100, wherein the substrate 10 is wetted with an electrolyte. Sex. A metal oxide core 14a is selected because it has a higher electrolyte wettability than the polymer substrate 10. In this and other examples, the ionic particle layer 30 composed of the ionic particles 14 having the metal oxide core 14a can improve the electrolyte wettability of the entire separator 100. The core material will be selected for its improved wettability to any liquid or electrolyte used in different applications, including battery applications. Examples of suitable electrolytes include, but are not limited to, propylene carbonate and other commercially available and non-commercially available electrolytes.

In some applications, the core material 14a is capable of enhancing the electrochemical properties of the separator. These characteristics may include reducing the resistance of the separator, increasing the impregnation of the electrolyte, and changing the effective ion migration number. In a related embodiment, the barrier film introduced into the core material 14a contributes to the performance of charge and discharge. The separator introduced into the core material 14a may also be suitable for high energy transfer, high transmission efficiency, or stable high speed/low speed charge and discharge battery elements.

As shown in FIG. 3B, the core 14a can be functionalized using a grafting agent and/or an anchor group 14b coupled to the core 14a. Any suitable grafting agent 14b can be used. Examples of suitable grafting agents 14b include, but are not limited to, trialkoxysilanes, phosphonates, sulfonates, and/or other bidentate ligands. Additional examples of suitable grafting agents 14b include primary amine-containing silanes, secondary amine-containing silanes, tertiary amine-containing methane (tertiary amine-containing) Silane), quaternary amine-containing silane, carboxylic acid containing silane, sulfonate containing silane or phosphoric acid containing compound -containing silane). Suitable grafting agent 14b comprises at least one terminal polyfunctional group (n 2), which has at least one of the following elements: nitrogen N sulfur S boron B phosphorus P carbon C 矽 Si oxygen O.

The grafting agent 14b can further comprise a functional group 18 having a net charge of 16, as depicted in Figure 3A-1. Suitable functional groups 18 include, but are not limited to, nitrogen-containing functional groups 18 having a single positive charge, as shown in Figure 3B. Examples of the latter include, for example, NR4+ functional groups (wherein R contains several elements including hydrogen), ammonium groups (NH4+), and the like. However, any suitable functional group having a net charge (positive or negative) can be used with the grafting agent 14b. Although FIG. 3B shows an anion Cl-, this is merely an example. Any suitable anion can be used; while other suitable anions can include bromide, fluoride, iodide, and other suitable anions.

In addition to the technique of using the grafting agent 14b, the core material 14a can also be modified by the prior art polymer electrolyte. Suitable techniques include the integration of nanopellets and macromolecules on colloidal particles (e.g., Frank Caruso, Science, 282, 1111 (1998).). As shown in Fig. 3A-2, the ionic particles 24 are synthesized by the polymer electrolyte 24b, and the ionic particles 14 are synthesized in some similar manner by the grafting agent 14b (Fig. 3A-1). The biggest difference in the process of Figures 3A-2 and 3A-1 is that there is no strong chemical covalent bond between the polymer electrolyte 24b and the core. However, the ionic particles 24 may still have substantially the same properties, functions, and characteristics as the prior art ionic particles 14 via the process of Figures 3A-2. In other words, the application and properties of the ionic particles 14 discussed in the present case will be equivalent to the ionic particles 24.

The polymer electrolyte 24b suitable for use in the drawing 3A-2 must have a relatively net charge (positive or negative). 3A-3 and 3A-4 respectively show polymer electrolytes which can be used in the present synthesis technique. 3A-3 is a positively charged polymer electrolyte poly(diallyldimethylammonium chloride). 3A-4 is a negatively charged polymer electrolyte poly(4-styrenesulfonic acid) lithium. Other suitable polymer electrolytes include: Polyallylamine hydrochloride, sodium 4-styrenesulfonate, Polysulfonate sodium (Polysulfate), Poly (Sodium Salt), Poly(Sodium Polystyrene Sulfate) Poly(p-xylene tetrahydrothiophenium chloride), and sodium polyacrylate (Poly(acrylic acid sodium salt). Suitable polymer electrolytes must have a suitable charge 28 and thus be on the surface of the ionic particles 24. An electrostatic charge 26 is introduced on it. In addition, the combination of positive and negative charges is also used in the implementation range.

As shown in the process of Fig. 3A-2, it contains a polymer electrolyte 24b which deposits an opposite charge at a specific pH value above the colloidal particles 14. The polymer electrolyte layer 24b is mainly build-up or stacked on the colloidal particles 14 by electrostatic attraction, and finally the ion particles 24 are formed. The polymer electrolyte after stable deposition still has an extra charge (positive or negative) group. It can be applied to the surface of the colloidal particles 14 or other unused charge groups, which may cause an overcompensation effect of the charge, which helps to stack the multilayered polymer electrolyte on the colloidal particles 14 by electrostatic attraction. 24b.

3C-1 and 3C-2 are schematic views showing a composition using the mixed material of the ionic particles of Figs. 3A-1 and 3A-2 and the treated polymer substrate or the like in accordance with the disclosed embodiment of the present invention. Figure 3D illustrates a schematic view of the hybrid material barrier of Figure 3C-1 in accordance with an embodiment of the present invention. Synthetic ionic particles 14 as described in the context of Figures 3A-1 and 3B or 3A-2 can be suspended in solution 20. Solution 20 can then contact substrate 10, particularly in contact with surface area 10a having a net charge 12. Suitable methods for introducing solution 20 and ionic particles 14 or 24 into substrate 10 include impregnation coating, spray coating, slot die coating, flow coating, gravure coating, ink jet coating, etc. The particles are coated on the surface of the substrate.

When the net charge 12 of the surface region 10a is electrically opposite to the net charge 16 on the ionic particles 14 or the net charge 26 on the ionic particles 24 (for illustration and illustration, as shown in Figures 3C-1 and 3C-2, respectively) The electronegativity and positive charge are shown to occur between the ionic particles 14 and 24 and the surface region 10a. In this example, the ionic particles 14 and 24 are combined with the surface region 10a, and a surface layer 30 composed of the ionic particles 14 and 24 is formed on the separator 100 as shown in Fig. 3D. 4A and 4B are photomicrographs of one of the synthetic ionic particles of Fig. 3A consistent with the disclosed embodiment and shown deposited on a charged substrate. The ionic particles 24 may be bonded to the surface region 10a to form ionic particles. The layered structure 30 is constructed on the substrate 100 of the separator.

Solution 20 can be one of several solutions suitable for depositing ionic particles 14 or 24. For example, suitable solutions include water (purification, deionization and/or with additives or other additions), various suitable organic solvents (eg, ethanol, acetone) or a mixture of the foregoing solutions and other solutions. Although many different solutions 20 can be used, an important consideration is the zeta-potential of the ionic particles 14 or 24 in solution 20, which is related to the overall charge required for the ionic particles 14 in solution 20. When the ionic particles 14 or 24 have a lower enthalpy (e.g., -30 mV < ζ < 30 mV) in the solution 20, a weak or low net surface charge is caused, thereby causing particle aggregation. The enthalpy changes in proportion to the repulsion between the ionic particles 14 or 24, which adversely affects the tendency of the ionic particles 14 or 24 to agglomerate or aggregate. Ion particles 14 or 24 with a higher enthalpy (for example: -30 mV > ζ or ζ > 30 mV) in solution result in a high surface charge of 12 and thus a stronger repulsion between the particles. Ion particles 14 or 24 with a low surface charge 12 tend to agglomerate. The ionic particles 14 or 24 having a relatively high surface charge 12 are subjected to a strong repulsion, and the effective coverage of the surface region 10a is suppressed or lowered. Varying the properties of solution 20 (e.g., pH) can alter the enthalpy of a particular set of ionic particles 14 or 24, thereby altering the deposition characteristics accordingly. For example, in solution 20, ionic particles 14 or 24 having a relatively large, positive enthalpy may result in uneven coverage on some surfaces. Although a range of pH values can be used in this case, the appropriate pH, enthalpy, and surface charge of the ionic particles 14 or 24 can be prepared for the particular application. In general, a pH of between 1 and 10 is suitable, although in some applications an out-of-range pH value will be used. Generally, a range of enthalpy values between -70 mV and 70 mV is suitable for producing a relatively uniform and stable ionic particle coating on the polymer substrate 10. However, it will be understood that the techniques described herein can be accompanied by any suitable threshold. In fact, the threshold can also be adjusted or changed to provide the desired coverage of the surface area 10a.

Although FIG. 3D illustrates a surface layer 30 which is constructed of ionic particles 14 or 24 uniformly distributed on the substrate 10, this is merely illustrative. In fact, the ionic particles 14 or 24 can be clustered, covered and/or attached to different portions of the surface region 10a of the substrate 10, as previously discussed.

4A and 4B are schematic views and a photomicrograph, respectively, consistent with the disclosed embodiments of the present invention, each showing double layer ionic particles deposited on a charged substrate. Figure 4A is a cross section showing the first layer 42 of positively charged ionic particles 44a deposited on a negatively charged substrate 10. The deposition step of the first layer 42 can be as described above for the contents of the ionic particles 14 and the surface layer 30. Once the first layer 42 is deposited, whether it is a single layer or a multiple layer, as shown in FIG. 4A, a second layer 46 of negatively charged ionic particles 44b can be deposited on the first layer 42. Although both FIGS. 4A and 4B show that the negatively charged ionic particles 44b are larger than the positively charged ionic particles 44a, this is merely illustrative. The particles 44a and 44b can be of any suitable size (e.g., 44a can be larger than 44b, and vice versa or the same size, etc.). Again, this particular charge arrangement is illustrative only. For example, substrate 10 can be positively charged, ionic particles 44a negatively charged, and ionic particles 44b positively charged. Those skilled in the art will recognize that other combinations are explicitly mentioned, implicit, metaphorical or unambiguous, and should be considered as different variations of the invention.

Figure 4B shows the results of two-layer deposition. As shown in Figure 4B, the double layers 42 and 46 are distinct. Although Figure 4B shows a portion of a double layer, it will be understood that any suitable form is within the scope of the invention. For example, the second layer 46 is patterned on the first layer 42 in a manner that produces island, ribbon or other patterned ionic particles 44b. Those skilled in the art will recognize that various arrangements of the layers 42 and 46, different patterns, and the like are within the scope of the present invention.

5A to 5C are photomicrographs showing a schematic diagram of the structure and combination of the separators using one of the ionic particles, and showing a conventional polymer separator material produced according to the procedure of Fig. 2. In Figure 5A, substrate 210 is a commercially available polymeric separator (Celgard 2320) for use in electrochemical cells. As shown in Fig. 5A, the substrate 210 is porous and has a plurality of fine pores 210c which are clearly visible on the photomicrograph. Figure 5B shows the substrate 210 of Figure 5A after plasma treatment wherein the surface region 210a has a net negative charge. The pores 210c are still visible on the treated surface as shown in Fig. 5B. Figure 5C shows surface area 210a after contact with ionized nanoparticle 214 having cerium oxide core 214a and grafting agent 214b, wherein grafting agent 214b comprises a positively charged ammonium group. Figure 5C shows a substantially identical and uniform coating 230 comprised of ionized nanoparticles 214 and covering surface area 210a. Further, as shown on FIG. 5C, many of the fine pores 210c appearing on the substrate 210 are not blocked by the coating layer 230.

Figures 5D through 5E are photomicrographs showing schematic diagrams of the structure and combination of barrier films using one of the relatively large ionic particles, and showing a conventional polymeric barrier film material made in accordance with the steps of Figures 2A through 2C. In Figure 5D, substrate 310 is a commercially available polymeric separator (Celgard 2320) for electrochemical cells. Surface area 310a has a net negative charge after plasma treatment. As shown in Fig. 5D, the substrate 310 is porous and has a plurality of fine pores 310c which are clearly visible on the photomicrograph. Figure 5E shows surface area 310a after contact with ionized nanoparticles 314 having ionized titanium particles 314a and grafting agent 314b, wherein grafting agent 314b comprises a positively charged ammonium group. Figure 5E shows a substantially identical and uniform coating 330 comprised of ionized nanoparticles 314 and covering surface area 310a. Further, as shown on FIG. 5E, some of the pores 210c appearing on the substrate 210 can still be seen after being covered by the ionic particle layer 330. The ionized nanoparticles 314 in the cladding 330 are much larger than the ionized nanoparticles 214, as shown in Figure 5C. Further, the ion nanoparticle 314 has a relatively irregular shape and particle size distribution as compared to the ion nanoparticle 214. These results show that some significant changes can be made by changing the core, deposition parameters and layer pattern.

6A and 6E illustrate two mechanisms for achieving formation of an ionic particle surface layer on a porous polymeric substrate in accordance with the relative charge density on the ionic particles and in accordance with the present disclosure. 6A and 6E illustrate the fine holes 10c in the surface region 10a. In some instances, the surface 10a is covered by ionic particles 14 to adjust the net surface charge 12 on the ionic particles 14. It should be noted that the pores 16c shown in Fig. 6A, and any of the pores discussed herein, are not necessarily limited to the surface region 10a, as shown in Fig. 6A. For example, the pores 10c, and any of the pores discussed herein, can be opened as shown in Figure 6B. Such an open pore 10c (shown in FIG. 6B), for example, includes pores formed in the surface region 10a or in the body portion 10b of the substrate 10 to form a network. In fact, a plurality of pores 10c applied to the substrate 10 of the battery separator may pass through the surface region 10a and/or form a network within the body 10b of the substrate 10.

In Figure 6A, the ionic particles 14 have a relatively high net surface charge 12. Figure 6D illustrates a transmission electron micrograph of a separator material made in accordance with the process of Figure 6A. Figure 6D is meant that in the case of a relatively high surface electrostatic charge 12, the ionic particles 14 will stack a relatively thin surface layer 30, and the ionic particles 14 will form a good overlay in the pores 10c.

When the particles 14 have a relatively high enthalpy in the deposition solution 20, a high net surface charge 12 is produced. A relatively high enthalpy can be positive or negative, as is the high net surface charge 12 of the ionic particles 14. A relatively high net surface charge 12 will cause a large net repulsion F1 between the ionic particles 14, as shown in Figure 6A. In some examples, this large net repulsion F1 is large enough to drive the ionic particles 14 into the pores 10c of the surface region 10a, as shown in Figures 6A, 6C and 6D. As shown in Figs. 6A and 6D, the coverage of the ionic particles 14 on the surface region 10c is relatively uniform at the outer edges of the pores 10c and at the outer surface 10a. However, the coverage of the ionic particles 14 on the surface region 10a shown in Figures 6A and 6D is merely illustrative. In fact, adjusting the net surface charge 12 of the ionic particles 14 can result in several different ways of covering the surface region 10a. For example, the net surface charge 12 of the ionic particles 14 can be adjusted such that there can be several layers of ionic particles 14 on the outer edge 10d of the surface region 10a, while the pores 10d can have a single layer of ionic particles 14 or less than a single layer. Ionic particles 14. The latter is roughly equivalent to the coverage shown in Fig. 6C. In addition, the net surface charge 12 of the ionic particles 14 can be adjusted such that the outer edge 10d of the surface region 10a can retain a single layer of ionic particles 14 or less than a single layer of ionic particles 14, while the pores 10d retain a single layer. The ionic particles 14 or more than a single layer of ionic particles 14. In still other variations, ionic particles 14 having different net surface charges 12 can be used simultaneously to cover portions of the outer edge 10d of the surface region 10a, portions of the pores 10c, or both.

In Figure 6E, the ionic particles 14 have a relatively low net surface charge 12. Figure 6F illustrates a transmission electron micrograph of a separator material made in accordance with the process of Figure 6E. Figure 6F is meant that in the case of a relatively low net surface charge, the ionic particles 14 will stack a relatively thick surface layer 30, and the ionic particles 14 do not appear to form any coating in the pores 10c. When the particles 14 have a relatively low enthalpy in the deposition solution 20, a low net surface charge 12 is produced. A relatively low enthalpy can be positive or negative, as is the low net surface charge 12 of the ionic particles 14.

The net repulsive force generated by the low net surface charge 12 between the ionic particles 14 is weaker than the gravitational force between the ionic particles 14, wherein the gravitational forces between the ionic particles 14 are caused by, for example, polarization effects. As the foregoing occurs, a significant net attractive force F2 will exist between the ionic particles 14, as shown in Figure 6E. In some instances, this apparent net attractive force F2 can be of a sufficient size to prevent the ionic particles 14 from entering the pores 10c of the surface region 10a, as shown in Figure 6E. Moreover, in some instances, this significant attractive force F2 will result in a surface layer 30 comprised of ionic particles 14, which may substantially cover the pores 10c. The coverage of the ionic particles 14 on the surface region 10a shown in Figure 6E is merely illustrative. In fact, adjusting the net surface charge 12 of the ionic particles 14 can result in several different ways of covering the surface region 10a. For example, the net surface charge 12 of the ionic particles 14 can be adjusted such that there may be several layers of ionic particles 14 on the outer edge 10d of the surface region 10a, while the pores 10d may or may not be surface layers composed of ionic particles 14. 30 covered. In other variations, ionic particles 14 having different net surface charges 12 may be used simultaneously to cover portions of the outer edge 10d of the surface region 10a, portions of the pores 10c, or both.

7A through 7B are transmission electron microscope images showing two other hybrid separators comprising porous polypropylene in accordance with the disclosed embodiments. In particular, Figures 7A and 7B show how different deposition parameters produce different coverage on an essentially identical exemplary substrate.

As shown in FIG. 7A, the substrate 410 of the separator 400 includes pores 410c, and other features. The ionic particles 414 are present in the pores 410c and accumulate on one surface region 410a of the substrate 10 to constitute an ionic particle layer 430. The thickness of the ionic particle layer 430 is composed of a plurality of ionic particles 414. The ionic particles 414 present in the pores 410c are overlaid on the pore walls 410d of the plurality of layers in the form of at least a single layer of ionic particles 414. In fact, the thickness of the ionic particle layer present on certain regions 415 within the pores 410c is significantly greater than the thickness of the monolayer. Furthermore, FIG. 7A shows that a plurality of fine holes 410c are covered by the ionic particle layer 430 on the surface region 410a of the substrate 410.

As shown in FIG. 7B, the substrate 510 of the separator 500 includes pores 510c, as well as other features. Fig. 7C illustrates that the ionic particles 514 cover the pore walls 510d, and this structure is also shown in Fig. 7B. 510e is a region composed of a polymer or a polypropylene. The ionic particles 514 are present in the pores 510c and in the form of an ionic particle layer 530 on one surface region 510a of the substrate 10, as shown in Figs. 7B and 7C. The ionic particle layer 530 can have a similar thickness to the ionic particle layer 430. The ionic particles 514 in the pores 510c cover almost the entire surface of the pore walls 510d in the manner of nearly single-layered ionic particles 514.

Comparative example 1

Figure 8 illustrates an electron micrograph top view of a separator 700 made in accordance with many of the disclosed aspects of the present disclosure. The fabrication is performed by depositing an ionic particle layer 730 on the surface of a barrier film substrate 710 similar to the commercially available release film 510 disclosed in FIG. 1C. Fig. 8 shows that even if the ionic particle layer 730 is covered, the pores 710c of the separator substrate 710 are still exposed.

The dimensional ratios of Figures 8A and 1C are similar. Comparing Figures 8A and 1C, it can be seen that the ionic particle layer 730 is more uniform than the particles 614 on the ceramic/non-woven separator 600. This is to be expected because, among other reasons, the ionic particles 714 have a few orders of magnitude and, therefore, in some instances, enhance the ability to form a uniform cover layer.

Furthermore, the ionic particle layer 730 retains at least some of the pores 710c of the underlying separator substrate 710. Conversely, adhesive 616 and particles 614 completely cover any pores of substrate 610.

Table 1: Comparison of features and characteristics of the ceramic/nonwoven separator and the barrier film 500 (Fig. 7B) shown in Fig. 1C.

Table 1 compares the ceramic/non-woven separator of the type disclosed in Figure 1C with the separator 700 of Figure 8. As shown in Table 1, the filler of the underlying substrate 710 is 40 to 60 times lower than the conventional ceramic/nonwoven separator. For this and other reasons, the separator 700 is capable of better electrochemical performance, wettability, chemical, thermal and mechanical stability and/or strength to the substrate 710 at relatively light weight. The ionic particle layer 830 of the separator does not require an adhesive, whereas a conventional ceramic/nonwoven separator requires about 15 weight percent (wt%) of the adhesive of the entire separator. Moreover, since the adhesion mechanism of the separator 700 is an ionic force, the adhesion between the ionic particle layer 730 and the substrate 710 is substantially stronger than the adhesion between the ceramic layer and the substrate in the conventional ceramic/nonwoven separator. Furthermore, although it is possible to form a plurality of layers of ionic particle layer 730 of any thickness, the ionic particle layer 730 can be as thin as a few nanometers. A typical ceramic layer within a ceramic/nonwoven release film, for example, may have a thickness on the order of the ceramic particle size, i.e., on a micron scale.

Comparative example 2

9A and 9B show the effect of ionic particles on the wettability of a commercially available propylene carbonate-containing electrolyte on a polymer substrate. Figure 9A illustrates an advancing contact angle of propylene carbonate on four different surfaces, wherein the four surfaces are respectively a commercially available polymeric barrier film surface (Celgard 2320, hereinafter referred to as "untreated" The separator 900"), the plasma-treated surface (MW-plasma treated Celgard 2320, hereinafter referred to as "plasma-treated separator 910"), and the plasma treated with single-layer ionic particles are commercially available. A molecular separator (HS30-silane3 monolayer coated MW-plasma treated Celgard 2320, hereinafter referred to as "single layer separator 920") and a plasma treated commercial polymer separator coated with multilayer ionic particles (HS30-silane3 multilayers coated) MW-plasma treated Celgard 2320, hereinafter referred to as "multilayer hybrid separator 930"). Figure 9B illustrates a schematic view of the contact angles on the four different surfaces of Figure 9A.

The contact angle is a measure of the wettability of a surface to propylene carbonate. It is generally advantageous for the battery separator to have an enhanced or maximum wettability to the electrolyte. This is especially true for separators used in batteries with particularly corrosive environments (eg, lithium-ion batteries). However, for some applications, it is sometimes preferable to not require wettability to the extreme. In many cases, it is advantageous to be able to adjust the wettability of the separator.

As shown in Figure 9A, the contact angle is reduced from about 65 to 30 degrees, which occurs on the surface where the Celgard 2320 is plasma treated. After the plasma treatment, increasing the wettability of the propylene carbonate may be related to the generation of a net surface charge (increasing polarity) on the surface. The wetting of the separator to propylene carbonate can be further improved after the addition of one layer of ionic particles. As shown in FIG. 9A, when the nanoparticle layer is added, the contact angle decreases (i.e., from the ionic particles of the 0 layer on the separators 910 and 920 to the ionic particles of one of the layers on the separator 930 and the separator 940). Multiple layers of ionic particles).

As shown in FIG. 9A, the multilayer hybrid separator 930 has a contact angle close to zero. This shows that, as shown in Fig. 9B, the propylene carbonate completely wets the surface of the separator 930. On the other hand, the contact angle of the separator 920 is 10 ± 2 degrees. This higher contact angle means lower wettability. Comparing the contact angle obtained by this example with the measurement separator 930, it can be obtained that: 1) under the existing conditions, the wettability seems to increase as the number of ionic particle layers increases. And 2) This particular example demonstrates that the wettability of HS30-silane3 multilayers coated MW-plasma treated Celgard 2320 can be adjusted by controlling the number of layers of deposited ionic particles.

Comparative example 3

Figure 10 shows the charge/discharge characteristics of a polymer separator before and after coating of ion particles, which is in accordance with the disclosed embodiment. As shown in FIG. 10, the specific capacity of the system including the ion nanoparticle mixed separator, and the specific capacity of the system including the DEC electrolyte are decreased as the number of cycles is increased. However, Figure 10 shows that the specific capacitance of the hybrid separator is significantly higher than the system containing the DEC electrolyte after 40 or more cycles. This shows that the cycle life of the hybrid separator is indeed substantially improved over commercially available alternatives.

As shown, the disclosed materials or techniques can enhance the electrochemical performance, chemical, thermal or mechanical strength of a device (eg, a battery separator) without substantially increasing weight.

As a result, the device is more rugged, yet does not sacrifice other important features related to functionality.

While some embodiments are discussed in the context of battery separators and other battery applications, they are merely illustrative and thus do not limit the substrate of the present disclosure to battery applications. For example, the disclosed materials and techniques can be applied to lightweight applications or other coating techniques for improving the mechanical, chemical or thermal durability of the product.

The technical and technical features of the present invention have been disclosed as above, and those skilled in the art can still make various substitutions and modifications without departing from the spirit and scope of the invention. Therefore, the scope of the present invention should be construed as being limited by the scope of the appended claims

1. . . Ceramic/polymer composite

2. . . Base

4. . . Oxyl

6. . . material

6a. . . particle

6b. . . Adhesive

10. . . Base

10a. . . Surface area

10b. . . main body

10c. . . Fine hole

10d. . . Outer edge

12. . . Net surface charge

14. . . Ionic particles

14a. . . Core

14b. . . Grafting agent

15a. . . fiber

15b. . . Base

15c. . . Microporous polymer substrate

15d. . . Fine hole

16. . . Net surface charge

16c. . . Fine hole

18. . . Surface layer

20. . . Solution

twenty four. . . Ionic particles

24b. . . Polymer electrolyte

26. . . Static charge

28. . . Electric charge

30. . . Surface layer

42. . . level one

44a. . . Ionic particles

44b. . . Ionic particles

46. . . Second floor

100. . . Base

210. . . Porous polymer substrate

210a. . . Surface area

210c. . . Fine hole

211. . . Inner pore

214. . . Ion nanoparticle

214a. . . Ceria core

214b. . . Grafting agent

220. . . Porous composite substrate

230. . . Coating

310. . . Porous polymer substrate

310a. . . Surface area

310c. . . Fine hole

314. . . Ion nanoparticle

314a. . . Titanium dioxide core

314b. . . Grafting agent

320. . . Porous composite substrate

330. . . Coating

410. . . Base

400. . . Isolation film

410c. . . Fine hole

410a. . . Surface area

410b. . . Deep area

410c. . . Fine hole

410d. . . Fine wall

414. . . Ionic particles

415. . . region

430. . . Ionic particle layer

500. . . Isolation film

510. . . Base

510a. . . Surface area

510c. . . Fine hole

510d. . . Fine wall

510e. . . region

514. . . Ionic particles

530. . . Ionic particle layer

600. . . Ceramic/nonwoven insulation film

614. . . Granule

616. . . Adhesive

630. . . Coating

700. . . Isolation film

710. . . Isolation film substrate

710c. . . Fine hole

714. . . Ionic particles

730. . . Ionic particle layer

830. . . Ionic particle layer

900. . . Untreated barrier

910. . . Plasma treated separator

920. . . Single layer isolation membrane

930. . . Multilayer hybrid separator

F1. . . Net repulsion

F2. . . Net attraction

1A illustrates a ceramic/polymer composite material as a conventional battery separator material;

Figure 1B is an electron micrograph of an exemplary substrate from SS Zhang et al. "A review on the separators of liquid electrolyte Li-ion batteries," Journal of Power Sources, Volume 164, Issue 1, 2007, page 351);

Figure 1C shows a top view of a ceramic/non-woven separator film from SS Zhang et al. "A review on the separators of liquid electrolyte Li-ion batteries," Journal of Power Sources, Volume 164, Issue 1, 2007, page 351;

2A to 2C illustrate an isolation film structure and combination using one of ionic particles in accordance with an embodiment of the present disclosure;

2D shows an electron micrograph of an exemplary substrate consistent with an embodiment of the present disclosure;

3A-1 and 3A-2 are schematic views showing the synthesis of an ion particle in accordance with an embodiment of the present invention;

3A-3 and 3A-4 show a polymer electrolyte used in accordance with the disclosed technique 3A-2 of the present invention;

3B is a close-up, cross-sectional view of one of the ionic particles synthesized according to the synthesis method of FIG. 3A-1 in accordance with one embodiment of the present disclosure;

3C-1 and 3C-2 show schematic views of a composite using the mixed material of the ionic particles of Figs. 3A-1 and 3A-2 and the treated polymer substrate;

3D illustrates a schematic view of the mixed material separator of FIG. 3C-1 in accordance with an embodiment of the present invention;

4A and 4B are schematic views and a photomicrograph, respectively, consistent with the disclosed embodiments of the present invention, each showing double layer ion particles deposited on a charged substrate;

5A to 5C are photomicrographs showing a structure of a separator structure and a combination using one of ionic particles, and showing a conventional polymer separator material produced according to the steps of FIG. 2;

5D to 5E are photomicrographs showing schematic views of the structure and combination of the separators using one of the relatively large ionic particles, and showing a conventional polymer separator material produced according to the steps of Figs. 2A to 2C;

6A to 6E are diagrams consistent with the disclosed embodiments, and exemplifying different structures of the surface layer of the ionic particles formed on the porous polymer substrate according to the corresponding charge density on the ionic particles;

6F illustrates a transmission electron micrograph of a separator material fabricated according to the process of FIG. 6E

7A to 7B are transmission electron microscope images showing a hybrid insulating film comprising two other porous polypropylenes in accordance with the disclosed embodiment;

Figure 7C illustrates the ionic particles covering the pore walls, also shown in Figure 7B;

Figure 8 illustrates an electron micrograph top view of a separator film fabricated in accordance with a number of disclosed aspects of the present disclosure, which deposits ionic particles on a surface of a commercially available separator substrate similar to that disclosed in Figure 8;

9A and 9B show the effect of ionic particles on the wettability of a commercially available propylene carbonate-containing electrolyte on a polymer substrate;

Figure 10 shows the charge/discharge characteristics of a polymer separator before and after coating of ion particles, which is in accordance with the disclosed embodiment.

10. . . Base

10a. . . Surface area

10b. . . main body

12. . . Net surface charge

14. . . Ionic particles

14a. . . Core

14b. . . Grafting agent

18. . . Surface layer

20. . . Solution

Claims (37)

An isolating film comprising: a substrate having a body portion and a surface portion, the surface portion having at least one porous region, wherein the at least one porous region has a net charge; and a plurality of ionic particles having the porous The net charge of the region is the opposite of a net charge, wherein the ion particles are attached to and coupled to an inner wall of the porous region to form a porous network having ionic particles. The isolating film of claim 1, wherein the ionic particles form at least one ionic particle layer, wherein the at least one ionic particle layer has a higher ratio of lithium, electrolyte, and electrolyte additive than the insulating substrate and the substrate High chemical stability, and the at least one ionic particle layer has a higher mechanical strength than the substrate. The separator of claim 1, wherein the ionic particles comprise nanoparticle having a size ranging from 1 nm to 500 nm. The separator of claim 1, wherein the substrate comprises a polymer material. The separator according to claim 1, wherein the ionic particles comprise a metal oxide, cerium oxide, zinc oxide, tin dioxide, titanium dioxide, zirconium oxide, aluminum oxide, barium titanate, cerium oxide, magnesium oxide, At least one of nickel oxide and calcium oxide. The isolating film of claim 1, wherein at least a portion of the ionic particles have a zeta potential value between -70 mV and 70 mV. The separator according to claim 1, further comprising at least one grafting agent coupled to the ionic particles. The separator according to claim 7, wherein the grafting agent comprises a primary amine-containing methane, a secondary amine-containing methane, a tertiary amine-containing methane, a quaternary amine-containing methane, and a carboxyl group. And at least one of methane, sulfonic acid-containing methane or a phosphoric acid-containing methane; or the grafting agent comprises at least one terminal polyfunctional group (n 2) It has at least one of the following elements: nitrogen, sulfur, boron, phosphorus, carbon, helium and oxygen. The separator according to claim 1 further comprising at least one polymer electrolyte. The separator of claim 9, wherein the at least one polymer electrolyte comprises at least one of the following elements: nitrogen, sulfur, boron, phosphorus, carbon, ruthenium and oxygen. The separator of claim 2, wherein the at least one ionic particle layer has a thickness of from 1 nm to 10 μm. The separator of claim 2, wherein the at least one ionic particle layer has a wettability to a liquid containing one of the electrolytes greater than a wettability of the liquid to the liquid. The separator of claim 12, wherein the separator substrate is an separator in an electrochemical cell. An electrochemical cell comprising a separator, the separator comprising: a substrate having a body portion and a surface portion, the surface portion having a porous region having a net charge; and a coating layer, Covering the surface portion, wherein the coating is formed by ionic particles, and the ionic particles have a net charge opposite to the net charge of the porous region; and a porous network having ionic particles is located in the porous region, Which should The porous network of ionic particles enters the porous region from the ionic particles and couples to an inner wall of the porous region. The electrochemical cell according to claim 14, wherein the substrate comprises a polymer material, and the coating further comprises metal oxide particles, wherein the metal oxide particles are modified by a grafting agent or a polymer electrolyte. Each of the metal oxide particles has a net charge. The electrochemical cell of claim 14, wherein the coating has a higher wettability to an electrolyte than the substrate. A method for preparing an isolating film, comprising the steps of: treating a substrate such that a surface portion of the substrate has a net charge; and coupling a plurality of ion particles to at least a portion of the surface portion, the ion particles having The surface charge of the surface portion is opposite to a net charge, wherein the coupling of the ion particles to at least a portion of the surface portion provides electrochemical, chemical stability, hygroscopicity, thermal stability, and strength of the separator. The character of at least one of the toughness. The preparation method according to claim 17, wherein the coupling forms at least one ionic particle layer, wherein the at least one ionic particle layer has higher chemical stability to lithium, an electrolyte, and an electrolyte additive additive than the substrate. And high mechanical strength. The preparation method according to claim 18, wherein the lithium contains at least one of lithium ion, lithium oxide, lithium phosphate, lithium fluoride or lithium carbon compound. The preparation method according to claim 17, wherein the step of treating a substrate comprises exposing the surface portion to a plasma. The preparation method according to claim 17, wherein the step of processing a substrate is The surface portion is chemically treated. The preparation method according to claim 17, wherein the step of treating a substrate comprises irradiating the surface portion with ultraviolet light. The preparation method according to claim 17, wherein the substrate comprises a polymer material. The method of claim 20, wherein the step of coupling the plurality of ionic particles to at least a portion of the surface portion comprises contacting the substrate with an aqueous solution containing ionized nanoparticles. The preparation method according to claim 24, wherein the step of contacting the substrate with the aqueous solution containing the ionized nanoparticles comprises dip coating, spray coating, slit die coating, flow coating, gravure coating or Inkjet coating to coat the ionic particles on the surface portion of the substrate. The preparation method according to claim 24, wherein the aqueous solution has a pH of between 1 and 10. The preparation method according to claim 17, further comprising: selecting a grafting agent to modify the plurality of metal oxide nanoparticles; and modifying the metal oxide nanoparticles by using the grafting agent to The ionized nanoparticles are prepared. The preparation method according to claim 27, wherein the step of selecting a grafting agent to modify the plurality of metal oxide nanoparticles further comprises selecting the grafting agent such that the ionized nanoparticle has a charge density, wherein The charge density corresponds to the desired coverage of one of the surface portions. The method of preparation of claim 28, wherein the charge density is a high charge density, and the desired coverage comprises infiltrating the ionized nanoparticles into the Within the pores of the substrate. The preparation method according to claim 28, wherein the charge density is a low charge density, and the desired coverage comprises the ion nanoparticle covering the pores of the substrate. The preparation method according to claim 27, wherein the grafting agent comprises a primary amine-containing methane, a secondary amine-containing methane, a tertiary amine-containing methane, a quaternary amine-containing methane, and a carboxyl group. At least one of methane, sulfonic acid-containing methane or a phosphoric acid-containing methane or the grafting agent comprising at least one terminal polyfunctional group (n 2) It has at least one of the following elements: nitrogen, sulfur, boron, phosphorus, carbon, helium and oxygen. The preparation method according to claim 18, wherein the at least one ionic particle layer has a thickness of from 1 nm to 10 μm. The preparation method according to claim 17, further comprising: selecting a polymer electrolyte to modify the plurality of metal oxide nanoparticles; and modifying the metal oxide nanoparticles by using the polymer electrolyte, To prepare the ionized nanoparticles. The preparation method according to claim 33, wherein the step of selecting a polymer electrolyte to modify the plurality of metal oxide nanoparticles further comprises selecting the polymer electrolyte such that the ion nano particles have a charge density, wherein The charge density corresponds to the desired coverage of one of the surface portions. The preparation method of claim 34, wherein the charge density is a high charge density, and the desired coverage comprises infiltrating the ionized nanoparticles into the Within the pores of the substrate. The preparation method according to claim 34, wherein the charge density is a low charge density, and the desired coverage comprises the ion nanoparticle covering the pores of the substrate. The preparation method according to claim 33, wherein the at least one polymer electrolyte contains at least one of the following elements: nitrogen, sulfur, boron, phosphorus, carbon, ruthenium and oxygen.