Insulating layer composition for secondary battery and secondary battery comprising same

Abstract

An insulating layer composition for a secondary battery according to an embodiment of the present disclosure includes: inorganic particles; a binder; an organic solvent; and a dispersant, wherein the dispersant includes a copolymer containing an acidic group. A secondary battery according to an embodiment of the present disclosure comprises: a current collector; an electrode disposed on the current collector; and an insulating layer including an insulating material on at least one side surface of the electrode, wherein the insulating material includes the insulating layer composition for a secondary battery.

Description

Insulating layer composition for secondary batteries and secondary batteries including the same

[0001] The present disclosure relates to an insulating layer composition for a secondary battery and a secondary battery comprising the same.

[0002] Recently, the development of secondary battery technology and the demand for it have been rapidly increasing, and in particular, research on secondary batteries with higher energy density, excellent lifespan, and high output characteristics is actively underway.

[0003] Meanwhile, as secondary batteries with higher energy density are being applied in various fields, research is being conducted to improve insulation between electrodes by forming an insulating layer on the outer edge of the electrode active material layer in order to construct safer electrodes.

[0004] Conventional electrode insulating layers have been formed using polymers with high heat and chemical resistance; however, these polymer electrode insulating layers suffer from reduced adhesion under high-temperature conditions and issues such as shrinkage during coating layer formation, which compromise battery safety. To address these problems, a technology has been proposed to improve the heat resistance and shrinkage issues of the insulating layer by using an insulating coating composition containing inorganic particles.

[0005] However, insulating layer compositions containing inorganic particles proposed to date lack the dispersibility of the inorganic particles, resulting in linear uncoated areas caused by clumping during coating and non-uniformity of the insulating layer after drying. In addition, there are problems such as weakened adhesion due to the non-uniformity of the insulating layer and partial degradation of insulation performance due to the non-uniform insulating layer.

[0006] The present disclosure aims to provide an insulating layer composition for a secondary battery that has excellent dispersibility of inorganic particles and excellent phase stability of the slurry, resulting in excellent coating properties, adhesion of the coating layer, and insulation performance of the coating layer.

[0007] In addition, the present disclosure provides a secondary battery with excellent battery safety comprising an electrode having an insulating layer composition for a secondary battery formed thereon.

[0008] An insulating layer composition for a secondary battery according to one embodiment of the present disclosure comprises inorganic particles; a binder; an organic solvent; and a dispersant, wherein the dispersant may comprise a copolymer comprising acidic groups.

[0009] A secondary battery according to one embodiment of the present disclosure comprises: a current collector; an electrode disposed on the current collector; and an insulating layer comprising an insulating material on at least one side of the electrode, wherein the insulating material may comprise an insulating layer composition for the secondary battery.

[0010] The insulating layer composition for a secondary battery according to the present disclosure provides excellent dispersibility and phase stability, thereby exhibiting excellent insulating properties when applied as an insulating layer for an electrode.

[0011] The insulating layer composition for a secondary battery according to the present disclosure has excellent coating properties, so when the insulating layer is coated, it exhibits a uniform coating thickness and can exhibit uniform insulation characteristics. The insulating layer composition for a secondary battery according to the present disclosure has excellent adhesion properties, so it can improve the battery stability of a secondary battery including it as an insulating layer.

[0012] The effects of the present disclosure are not limited to those mentioned above, and other unmentioned effects will be clearly understood by those skilled in the art from the description below.

[0013] FIG. 1 is a cross-sectional view of a secondary battery according to various embodiments of the present disclosure.

[0014] Hereinafter, various embodiments of this document are described with reference to the accompanying drawings. The embodiments and the terms used therein are not intended to limit the technology described in this document to specific embodiments and should be understood to include various modifications, equivalents, and / or substitutions of said embodiments.

[0015]

[0016] Insulating layer composition for secondary batteries

[0017] The insulating layer composition for a secondary battery according to the present disclosure may be formed on at least one side of an electrode to prevent an internal short circuit of the secondary battery.

[0018] An insulating layer composition for a secondary battery according to the present disclosure may include inorganic particles, a binder, and a dispersant. An insulating layer composition for a secondary battery according to the present disclosure may include inorganic particles, a binder, an organic solvent, and a dispersant.

[0019] The insulating layer composition for a secondary battery according to the present disclosure may include a copolymer containing acidic groups as a dispersant.

[0020] The insulating layer composition for a secondary battery according to the present disclosure provides excellent dispersibility and phase stability, thereby exhibiting excellent insulating properties when applied as an insulating layer for an electrode.

[0021] The insulating layer composition for a secondary battery according to the present disclosure has excellent coating properties, so when the insulating layer is coated, it exhibits a uniform coating thickness and can exhibit uniform insulation characteristics. The insulating layer composition for a secondary battery according to the present disclosure has excellent adhesion properties, so it can improve the battery stability of a secondary battery including it as an insulating layer.

[0022] (1) Inorganic particles

[0023] The insulating layer composition for a secondary battery according to the present disclosure may include inorganic particles. The inorganic particles may include, as a non-limiting example, at least one selected from the group consisting of alumina, aluminum hydroxide, barium titanium oxide, magnesium oxide, magnesium hydroxide, clay, titanium oxide, glass powder, and boehmite.

[0024] Preferably, the inorganic particles may include boehmite. The boehmite may be aluminum oxide-hydroxide.

[0025] The diameter of the inorganic particles may be in the range of 0.001 to 10 μm to form an insulating layer of uniform thickness and appropriate porosity.

[0026] Inorganic particles may be included in an amount of 4.9 to 32.5 parts by weight per 100 parts by weight of the insulating layer composition for a secondary battery. Preferably, inorganic particles may be included in an amount of 7.8 to 30.0 parts by weight per 100 parts by weight of the insulating layer composition for a secondary battery.

[0027] Inorganic particles may be included in an amount of, for example, 50 to 90 parts by weight based on the total weight of the insulating layer. Preferably, inorganic particles may be included in an amount of 50 to 85 parts by weight based on the total weight of the insulating layer. More preferably, inorganic particles may be included in an amount of 65 to 85 parts by weight based on the total weight of the insulating layer. When the content of inorganic particles falls within the aforementioned range, an insulating effect resulting from the use of inorganic particles can be achieved.

[0028] (2) Binder

[0029] The insulating layer composition for a secondary battery according to the present disclosure may include a binder. Binders are, by non-limiting example, polyacrylic acid, polymethacrylic acid, ethylene-acrylic acid copolymer, ethylene-methacrylic acid copolymer, butadiene-acrylic acid copolymer, butadiene-methacrylic acid copolymer, polyvinylsulfonate, chlorosulfonated polyethylene, perfluorosulfonated ionomer, sulfonated polystyrene, styrene-acrylic acid copolymer, sulfonated butyl rubber, polyvinylidene fluoride (PVdF), polyvinylidene fluoride-hexafluoropropylene (PVdF-HFP), polyvinylpyrrolidone, polyacrylonitrile, polyvinylidene fluoride-trichloroethylene, polyvinylidene fluoride-chlorotrifluoroethylene (PVdF-TFE), polymethyl methacrylate, polyvinyl acetate, ethylene-co-vinyl acetate copolymer, It may include at least one selected from the group consisting of polyethylene oxide, cellulose acetate, cellulose acetate butyrate, cellulose acetate propionate, cyanoethyl pullulan, cyanoethyl polyvinyl alcohol, cyanoethyl cellulose, cyanoethyl sucrose, pullulan, carboxymethylcellulose, acrylonitrile styrene butadiene copolymer, and polyimide.

[0030] Preferably, the binder may include polyvinylidene fluoride (PVdF) and styrene butadiene rubber (SBR).

[0031] The binder may be included in an amount of 5 to 15 parts by weight per 100 parts by weight of the insulating layer composition for a secondary battery. Preferably, the binder may be included in an amount of 7 to 13 parts by weight per 100 parts by weight of the insulating layer composition for a secondary battery.

[0032] The binder may be included in an amount of, for example, 8 to 40 parts by weight based on the total weight of the insulating layer. Preferably, the binder may be included in an amount of 10 to 35 parts by weight based on the total weight of the insulating layer. More preferably, the binder may be included in an amount of 10 to 33 parts by weight based on the total weight of the insulating layer. When the content of the binder falls within the aforementioned range, the coating properties can be improved.

[0033] (3) Dispersant

[0034] The insulating layer composition for a secondary battery according to the present disclosure may include a dispersant. The dispersant may include a copolymer containing an acidic group. For example, the dispersant may include at least one selected from the group consisting of alkylol ammonium salt copolymers, alkyl ammonium salt copolymers, modified alkylol ammonium salt copolymers, modified alkyl ammonium salt copolymers, acrylate copolymers, and polypropylene glycol copolymers.

[0035] Preferably, the dispersant may be an alkylol ammonium salt copolymer. The alkylol ammonium salt copolymer may be an alkylol ammonium salt copolymer containing an acidic group formed by reacting a copolymer containing a carboxylic acid with an alkylol ammonium compound.

[0036] The acid value (mgKOH / g) of the alkylol ammonium salt copolymer may be 50 to 150. Preferably, the acid value (mgKOH / g) of the alkylol ammonium salt copolymer may be 70 to 130. More preferably, the acid value (mgKOH / g) of the alkylol ammonium salt copolymer may be 90 to 120. If the acid value of the alkylol ammonium salt copolymer is less than 50, the dispersion effect may be reduced, and if it exceeds 150, the phase stability of the composition may be reduced.

[0037] The dispersant may be included in an amount of 0.5 to 7.0 parts by weight per 100 parts by weight of inorganic particles. Preferably, the dispersant may be included in an amount of 3 to 5 parts by weight per 100 parts by weight of inorganic particles.

[0038] The dispersant may be included in an amount of 0.1 to 2.5 parts by weight per 100 parts by weight of the insulating layer composition for a secondary battery. Preferably, the dispersant may be included in an amount of 0.2 to 2.0 parts by weight per 100 parts by weight of the insulating layer composition for a secondary battery.

[0039] The dispersant may be included in an amount of, for example, 1 to 5 parts by weight based on the total weight of the insulating layer. Preferably, the dispersant may be included in an amount of 2 to 4 parts by weight based on the total weight of the insulating layer. More preferably, the dispersant may be included in an amount of 2.5 to 3.5 parts by weight based on the total weight of the insulating layer. When the content of the dispersant falls within the aforementioned range, dispersibility and coating properties can be improved.

[0040] (4) Organic solvent

[0041] The insulating layer composition for a secondary battery according to the present disclosure may include an organic solvent. Non-limiting examples of organic solvents may include at least one selected from the group consisting of acetone, tetrahydrofuran, methylene chloride, dimethylformamide, dimethylacetamide, ethanol, methanol, and N-methyl-2-pyrrolidone (NMP).

[0042] Preferably, the organic solvent may include N-methyl-2-pyrrolidone.

[0043] The organic solvent may be included in an amount of 50 to 90 parts by weight per 100 parts by weight of the insulating layer composition for a secondary battery. Preferably, the organic solvent may be included in an amount of 55 to 85 parts by weight per 100 parts by weight of the insulating layer composition for a secondary battery. When the content of the organic solvent falls within the aforementioned range, dispersibility and coating properties can be improved.

[0044] The viscosity of the insulating layer composition for a secondary battery according to the present disclosure may be 500 to 10,000 cp. Preferably, the viscosity may be 1,000 to 8,000 cp. More preferably, the viscosity may be 2,000 to 6,000 cp. When the viscosity of the composition falls within the aforementioned range, the coating properties and peel strength can be improved.

[0045] The thickness of the insulating layer formed from the insulating layer composition for a secondary battery according to the present disclosure may be 1 to 50 μm. Preferably, the thickness of the insulating layer may be 10 to 40 μm. More preferably, the thickness of the insulating layer may be 15 to 25 μm. When the thickness of the insulating layer falls within the aforementioned range, the peel strength of the insulating layer can be improved.

[0046] An insulating layer composition for a secondary battery according to the present disclosure and an insulating layer formed therefrom may satisfy any one of the following formulas 1 to 5.

[0047] [Equation 1]

[0048] 100 < R / T <350

[0049] [Equation 2]

[0050] 100 < R / T <300

[0051] [Equation 3]

[0052] 120< R / T <320

[0053] [Equation 4]

[0054] 130< R / T <300

[0055] [Equation 5]

[0056] 130< R / T <280

[0057] (In the above Equations 1 to 5, R is the viscosity (cp) of the composition, and T is the thickness (um) of the insulating layer after drying.)

[0058] When the above equation is satisfied, the insulating layer composition for secondary batteries maintains excellent dispersibility and phase stability, thereby maximizing coating properties and adhesion.

[0059] The particle size D99 of the particles included in the insulating layer composition for a secondary battery may be greater than 5 μm and less than 9 μm. Preferably, the particle size D99 of the particles included in the insulating layer composition for a secondary battery may be 6 μm to 8 μm, or 7 μm to 8 μm.

[0060] When the insulating layer composition for a secondary battery according to the present disclosure satisfies the above formula and the particle size D99 of the particles simultaneously satisfies the aforementioned range, it can have excellent dispersibility and phase stability, and the coating properties and adhesion properties can be maximized.

[0061]

[0062] secondary battery

[0063] The secondary battery according to the present disclosure may include the insulating layer composition for the secondary battery described above. The secondary battery according to the present disclosure may be a lithium-ion secondary battery.

[0064] A secondary battery according to the present disclosure may include a current collector, an electrode disposed on the current collector, and an insulating layer formed from the above-described composition. More specifically, a secondary battery according to the present disclosure may include a positive current collector, a positive electrode disposed on the positive current collector, and an insulating layer formed from the above-described composition on at least one side of the positive electrode.

[0065] FIG. 1 is a cross-sectional view of a secondary battery according to one embodiment of the present disclosure.

[0066] Referring to FIG. 1, a secondary battery according to the present disclosure may include a positive current collector (110), a positive electrode (120), an insulating layer (130), a separator (140), a negative electrode (160), and a negative current collector (150).

[0067] The positive current collector (110) may include a material having high conductivity without causing chemical changes in the secondary battery. For example, stainless steel, aluminum, nickel, titanium, calcined carbon, etc. may be used, and in the case of aluminum or stainless steel, a surface treated with carbon, nickel, titanium, silver, etc. may be used.

[0068] A positive electrode (120) containing a positive active material may be disposed on one or both sides of a positive electrode current collector (110).

[0069] The negative current collector (150) may be positioned facing the positive current collector (110). The negative current collector (150) may include a material that has high conductivity without causing chemical changes in the secondary battery. For example, copper, stainless steel, nickel, titanium, calcined carbon, etc. may be used, and in the case of copper or stainless steel, a surface-treated material such as carbon, nickel, titanium, silver, etc. may be used.

[0070] A cathode (160) containing a cathode active material may be disposed on one or both sides of a cathode current collector (150).

[0071] A separator (140) may be disposed between the anode (130) and the cathode (160). The separator (140) may be an insulating thin film having high ion permeability and mechanical strength. The separator (140) is not particularly limited as long as it is commonly used in the industry, but specifically, a sheet or nonwoven fabric made of chemically resistant and hydrophobic polypropylene, glass fiber, or polyethylene may be used, and in some cases, a composite separator in which inorganic particles / organic particles are coated with an organic binder polymer on a porous polymer substrate such as a sheet or nonwoven fabric may be used.

[0072] Meanwhile, the positive current collector (110) may be defined with a positive placement section (A1) where the positive (120) is placed and a non-positive section (A2) where the positive (120) is not placed.

[0073] An insulating layer (130) may be disposed in the uninsulated portion (A2). An insulating layer (130) may be disposed on at least one side of the anode (120). An insulating layer (130) may be disposed at at least one end of the anode (120). An insulating layer (130) may be disposed to cover a portion of the anode (120) from at least a portion of the uninsulated portion (A2).

[0074] The thickness (T) of the insulating layer (130) may be 1 to 50 μm. Preferably, the thickness (T) of the insulating layer (130) may be 10 to 40 μm. More preferably, the thickness (T) of the insulating layer (130) may be 15 to 25 μm. When the thickness (T) of the insulating layer (130) falls within the aforementioned range, the peel strength of the insulating layer (130) can be improved.

[0075] As described above, the insulating layer composition for a secondary battery and the insulating layer (130) formed therefrom according to the present disclosure can satisfy the following formula.

[0076] 100 < R / T <350

[0077] (In the above formula, R is the viscosity of the composition (cp), and T is the thickness of the insulating layer after drying (um))

[0078] If the above equation is satisfied, the coating properties and adhesion of the insulating layer (130) can be maximized.

[0079] One end of the insulating layer (130) may be positioned to correspond to one end of the cathode (160). Alternatively, one end of the insulating layer (130) may be positioned to be at least the same length as or longer than one end of the cathode (160).

[0080] The insulating layer (130) can prevent a short circuit by preventing contact between the positive electrode (130) and the negative electrode (160) when the end of the separator (140) shrinks due to reaction heat generated during the operation of the secondary battery. Therefore, the stability of the secondary battery can be improved.

[0081]

[0082] The present invention will be explained in more detail below through examples. However, the following examples are intended only to aid in understanding the present invention and do not imply that the scope of the present invention is limited to these examples in any way.

[0083]

[0084] Example 1

[0085] Boehmite (NA&L APYRAL® AOH 30) was prepared as an inorganic particle, an alkylol ammonium salt copolymer with an acid value of 94 mgKOH / g (BYK ET3004) as a dispersant, a mixture of PVdF and SBR (Syensqo solef5130 + NA&L AL-3001A) as a binder, and NMP as an organic solvent.

[0086] An insulating layer composition for a secondary battery was prepared by composing inorganic particles : dispersant : binder in a weight ratio of 80 : 3.2 : 16.8 and including 70 parts by weight of an organic solvent per 100 parts by weight of the composition. An Al foil was prepared as a positive current collector, and the insulating layer composition was coated onto the Al foil using a bar coating method, followed by hot air drying to form an insulating layer.

[0087]

[0088] Example 2

[0089] An insulating layer was formed in the same manner as in Example 1, except that the inorganic particles: dispersant: binder were mixed in a weight ratio of 85:3.4:11.6.

[0090]

[0091] Example 3

[0092] An insulating layer was formed in the same manner as in Example 1, except that the inorganic particles : dispersant : binder were mixed in a weight ratio of 65 : 2.6 : 32.4.

[0093]

[0094] Example 4

[0095] An insulating layer was formed in the same manner as in Example 1, except that an alkylol ammonium salt copolymer (BYK ET3004) with an acid value of 120 mgKOH / g was used as a dispersant.

[0096]

[0097] Comparative Example 1

[0098] An insulating layer was formed in the same manner as in Example 1, except that the inorganic particles and binder were mixed in a weight ratio of 80 to 20.

[0099]

[0100] Comparative Example 2

[0101] Phosphoric acid ester (BYK ET3003) with an acid value of 129 mgKOH / g was prepared as a dispersant.

[0102] An insulating layer was formed in the same manner as in Example 1, except that the inorganic particles: phosphate ester dispersant: binder were mixed in a weight ratio of 80: 3.2: 16.8.

[0103]

[0104] Comparative Example 3

[0105] Tannic acid (Daejeonghwageum Tannic acid) with an acid value of 600 mgKOH / g was prepared as a dispersant.

[0106] An insulating layer was formed in the same manner as in Example 1, except that the inorganic particles : tannic acid dispersant : binder were mixed in a weight ratio of 80 : 3.2 : 16.8.

[0107]

[0108] Comparative Example 4

[0109] An insulating layer was formed in the same manner as in Example 1, except that the inorganic particles : dispersant : binder were mixed in a weight ratio of 90 : 3.6 : 6.4.

[0110]

[0111] Comparative Example 5

[0112] An insulating layer was formed in the same manner as in Example 1, except that the inorganic particles : dispersant : binder were mixed in a weight ratio of 60 : 2.4 : 37.6.

[0113]

[0114] Experimental Example

[0115] The insulating layer compositions for secondary batteries and the physical properties of the insulating layers prepared in Examples 1 to 3 and Comparative Examples 1 to 5 were tested as follows, and the results are listed in Table 1 below.

[0116]

[0117] (1) Particle size of the composition for electrode insulation coating

[0118] The particle sizes D50 and D99 of the composition were measured using a particle size analyzer (Microtrac S3500).

[0119]

[0120] (2) Viscosity

[0121] Viscosity was measured using a viscometer (Brookfield DVPlus) with spindle No. 62 at 25°C with a torque value of 70% or higher.

[0122]

[0123] (3) Coating properties

[0124] An insulating coating layer was formed by coating aluminum foil to a thickness of 20 µm using an automatic coating machine (LK Lab Korea AFA350V) and then drying it.

[0125] The insulating coating layer was visually inspected to check for defects, and its thickness was measured and evaluated as follows.

[0126]

[0127] O : No surface abnormalities and coating layer thickness deviation of ±2um or less

[0128] △ : No surface abnormalities and coating layer thickness deviation of ±2um or more

[0129] X: Occurrence of coating stains, coating pinholes, linear uncoated areas, etc. on the surface, and thickness deviation of ±2um or less

[0130] XX: Occurrence of coating stains, coating pinholes, linear uncoated areas, etc. on the surface, and thickness deviation of ±2um or more

[0131]

[0132] (4) Peel strength

[0133] After attaching the coated surface of the sample to the steel plate using double-sided tape (3M), the peel strength of the coating layer was measured by pulling the steel plate and the sample 180° at a speed of 200 m / min using a tensile strength tester (Inston).

[0134]

[0135] (5) Phase stability

[0136] After leaving the electrode insulation coating composition at 50°C for 14 days, the particle size was measured to check the deviation from the initial measured particle size and evaluated as follows.

[0137] O : Particle size variation 5% or less

[0138] X: Particle size variation 5% or more

[0139] XX: Particle size variation 15% or more

[0140]

[0141] Example Comparative Example 1 2341 2345 Particle Size D 50 (μm) 2.49 2.45 2.52 2.50 4.96 3.12 2.49 2.76 2.61 D 99 (μm) 7.7 4 7.6 5 7.9 5 7.8 0 3 8.9 2 1 8.5 4 10.4 17.9 7 8.21 Viscosity cp 3 9 9 4 2 7 8 5 5 2 6 4 0 2 3 4 5 9 4 2 5 5 3 8 7 4 9 7 2 9 7 02 Peel Strength (N / 15mm) 7.2 8 7.3 2 7.5 1 7.4 2 4.2 1 5.6 6 5.1 2 6 7 8 6.99 Coating Thickness μm 2 0 1 9 2 1 1 4.4 2 1 2 2 0 1 6 24 Coating Properties OOOXXX△△△ Phase Stability OOOXXXXXXX R / T 2 0 1 4 7 2 4 9 2 7 8 R / T : R is the viscosity (cp) of the coating composition, and T is the thickness of the coating layer after drying (μm), rounded value.

[0142]

[0143] As shown in Table 1 above, it was confirmed that the composition for electrode insulation coating for secondary batteries of Examples 1 to 4 according to the present disclosure and the insulating layer formed thereby exhibited excellent effects in all measured physical properties.

[0144] Specifically, as in Examples 1 to 4, when an alkylol ammonium salt copolymer with an acid value (mgKOH / g) of 50 to 150, 70 to 130, or 90 to 120 is used as a dispersant, it can be seen that the coating properties and phase stability are excellent.

[0145] In addition, as in Examples 1 to 4, 100 < R / T < 350, or 100 <R / T<300, 또는 120< R / T <320, 또는 130< R / T <300, 또는 130< R / T <280을 만족함과 동시에, 조성물에 포함된 입자의 입도 D99가 5 um 초과 9 um 미만을 함께 만족할 경우, 박리강도, 코팅성 및 상안정성을 모두 극대화할 수 있음을 확인하였다.

[0146]

[0147] Embodiments of the present disclosure have been described above together with the drawings. This is illustrative and the present disclosure is not limited to the aforementioned embodiments and the contents of the drawings.

[0148] It is obvious to those skilled in the art that the present disclosure may be modified within the scope of the technical concept disclosed. The described embodiments should be regarded as part of the present disclosure, and the scope of the present disclosure should not be determined solely by the described embodiments.

[0149] The scope of the present disclosure should be determined by the technical ideas described in the claims. Furthermore, even if the operation or effect according to the configuration is not explicitly described while describing the embodiments of the present disclosure, it is obvious that the operation or effect predictable by said configuration should also be recognized as part of the present disclosure.

Claims

1. Comprising inorganic particles; a binder; an organic solvent; and a dispersant, The above-mentioned dispersant comprises a copolymer containing acidic groups, an insulating layer composition for a secondary battery.

2. In Paragraph 1, The above-mentioned dispersant comprises at least one selected from the group consisting of alkylol ammonium salt copolymer, alkyl ammonium salt copolymer, modified alkylol ammonium salt copolymer, modified alkyl ammonium salt copolymer, acrylate copolymer, and polypropylene glycol copolymer, an insulating layer composition for a secondary battery.

3. In Paragraph 1, An insulating layer composition for a secondary battery, wherein the above-mentioned dispersant is included in an amount of 0.5 to 7.0 parts by weight per 100 parts by weight of inorganic particles.

4. In Paragraph 1, An insulating layer composition for a secondary battery, wherein the above-mentioned inorganic particles comprise at least one selected from the group consisting of alumina, aluminum hydroxide, barium titanium oxide, magnesium oxide, magnesium hydroxide, clay, titanium oxide, glass powder, and boehmite.

5. In Paragraph 1, The above binder is polyacrylic acid, polymethacrylic acid, ethylene-acrylic acid copolymer, ethylene-methacrylic acid copolymer, butadiene-acrylic acid copolymer, butadiene-methacrylic acid copolymer, polyvinylsulfonate, chlorosulfonated polyethylene, perfluorosulfonated ionomer, sulfonated polystyrene, styrene-acrylic acid copolymer, sulfonated butyl rubber, polyvinylidene fluoride (PVdF), polyvinylidene fluoride-hexafluoropropylene (PVdF-HFP), polyvinylpyrrolidone, polyacrylonitrile, polyvinylidene fluoride-trichloroethylene, polyvinylidene fluoride-chlorotrifluoroethylene (PVdF-TFE), polymethyl methacrylate, polyvinyl acetate, ethylene-co-vinyl acetate copolymer, polyethylene oxide, An insulating layer composition for a secondary battery comprising at least one selected from the group consisting of cellulose acetate, cellulose acetate butyrate, cellulose acetate propionate, cyanoethyl pullulan, cyanoethyl polyvinyl alcohol, cyanoethyl cellulose, cyanoethyl sucrose, pullulan, carboxymethylcellulose, acrylonitrile styrene butadiene copolymer, and polyimide.

6. In Paragraph 1, An insulating layer composition for a secondary battery, wherein the above organic solvent comprises at least one selected from the group consisting of acetone, tetrahydrofuran, methylene chloride, dimethylformamide, dimethylacetamide, ethanol, methanol, and N-methyl-2-pyrrolidone (NMP).

7. In Paragraph 1, With respect to 100 parts by weight of the above composition, 4.9 to 32.5 parts by weight of the above inorganic particles; 0.1 to 2.5 parts by weight of the above dispersant; 5 to 15 parts by weight of the above binder; and An insulating layer composition for a secondary battery comprising 50 to 90 parts by weight of the above organic solvent.

8. In Paragraph 1, The above composition and the insulating layer formed therefrom are insulating layer compositions for secondary batteries satisfying Formula 1 below. [Equation 1] 100 < R / T <350 (In Equation 1 above, R is the viscosity of the composition (cp), and T is the thickness of the insulating layer after drying (um)) 9. In Paragraph 1, An insulating layer composition for a secondary battery, wherein the viscosity of the above composition is 500 to 10,000 cp.

10. In Paragraph 1, An insulating layer composition for a secondary battery, wherein the thickness of the insulating layer formed from the above composition is 1 to 50 μm.

11. In Paragraph 1, An insulating layer composition for a secondary battery, wherein the particle size D99 of the particles included in the above composition is greater than 5 μm and less than 9 μm.

12. Entire house; Electrode disposed on the above current collector; and The above electrode includes an insulating layer comprising an insulating material on at least one side thereof, and The above insulating material is a secondary battery comprising a composition according to any one of claims 1 to 11.

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