KR20190134229A - Thermally Conductive Composition - Google Patents

Abstract

The present invention relates to a thermally conductive composition and a use thereof. The thermally conductive composition is applied to various applications and has suitable compression flow characteristics, adhesion characteristics, heat dissipation characteristics, thermal conductivity, reworkability, storage stability, insulation characteristics, storage stability, and durability.

Description

Thermally Conductive Composition

The present application is directed to thermally conductive compositions, thermally conductive clays or gap fillers.

Compositions capable of conducting heat are required in various fields.

For example, in the computer industry there is a continuing movement towards higher computing power and speed. Microprocessors are being made with smaller feature sizes for increased computational speed. Thus, power flux is increased and more heat is generated per unit area of the microprocessor. As the heat output of microprocessors increases, heat or 'thermal management' is becoming more and more difficult. One aspect of thermal management is known in the industry as "thermal interface material" or "thermal interface material" (TIM), whereby such material is disposed between a heat source, such as a microprocessor, and a heat dissipation device to aid in heat transfer. Examples of such TIMs include Thermally Conductive Compositions.

In addition, a thermally conductive composition may be required in the process of manufacturing the battery pack. The secondary battery includes a nickel cadmium battery, a nickel hydrogen battery, a nickel zinc battery or a lithium secondary battery, and a lithium secondary battery is typical. A structure housed in a case after electrically connecting a plurality of secondary batteries is called a battery module. For example, Patent Document 1 describes the battery module, which is manufactured in a simple and low-cost process, while providing heat dissipation characteristics and energy to volume. A battery module having excellent efficiency is disclosed. In applications where higher output is required, so-called battery packs are constituted by storing a plurality of such battery modules electrically connected to each other and being stored in a case or the like. As described above, in the process of implementing the battery pack, a thermally conductive composition may be required between the battery module and the battery module and / or between the battery module and the case of the battery pack.

Korean Laid-Open Patent No. 2016-0105354

The present application provides a thermally conductive composition and its use.

The thermally conductive composition of the present application, at least an oil component; And fillers. In the above, the filler may be a thermally conductive filler. The thermally conductive composition may be used in various applications, and as described below, the thermally conductive composition may be a battery pack configured to accommodate a plurality of battery modules in a case, and / or between the battery module and / or the battery pack. It may be located between the case and the battery module.

The physical properties required for the thermally conductive composition for the above uses, the proper adhesion to effectively maintain a plurality of battery modules, the thermal conductivity to efficiently transfer the heat generated from the module to the case of the pack, the assembly process of the battery pack Re-workability, which will allow the module to be detached and reattached to the module, properties that will not damage the case or module, insulation properties, storage stability and Durability and the like, and the thermally conductive composition of the present application can stably satisfy the above characteristics.

The thermally conductive composition of the present application may be a grease type composition by including an oil component. The term grease means a material having a shear rate of 1 / s and a viscosity of greater than 1,000 cP at 20 ° C. and a viscosity of 1 / s and a viscosity of less than 100,000,000 cP at 125 ° C. The grease type composition can mean a very sticky lubricating oil type composition which is usually used in the friction part of a machine, and usually exhibits a high viscosity while being semisolid.

The thermally conductive composition of the present application may be uncured. Uncured means that there are no components in the thermally conductive composition capable of causing a curing reaction. Uncuring the thermally conductive composition is advantageous for securing reworkability among the required physical properties.

Among the properties required in the thermally conductive composition to be applied to applications such as the present application is a suitable squeeze flow. In the above, the pressurized flow is about 1 mm / s until the height becomes about 0.3 mm from the top and the bottom after molding the heat conductive composition into a cylindrical shape (bottom diameter: about 8 mm, height: about 3 mm). It means the force at the time when the height is about 0.5 mm when measuring the applied force while pressing. Specific ways of measuring the compression flow are described in the Examples. In the case of a thermally conductive composition for use as in the present application, the compression flow measured in the above manner may be about 700 gf or less.

The compression flow may be about 700 gf or less, 680 gf or less, 660 gf or less or 640 gf or less, or about 50 gf or more, 100 gf or more, 150 gf or more, 200 gf or more, 250 gf or more, 300 gf or less in another example. At least 350 gf, at least 400 gf, at least 450 gf, at least 500 gf, or at least about 550 gf.

The thermally conductive composition having such a pressurized flow spreads widely even with a small force, does not generate gold even when the applied pressure is lost, and may exhibit good agglomeration between the thermally conductive compositions.

Such pressurized flow can be achieved by selecting and applying the appropriate component as a component that acts as a dispersant.

Of the physical properties mentioned in the present specification, in the case of physical properties in which the measured temperature or pressure affect the results, unless otherwise specified, the physical properties are physical quantities measured at normal temperature and normal pressure.

The term ambient temperature is a naturally occurring temperature that is warmed or undecreased and may be, for example, a temperature in the range of about 20 ° C. to about 30 ° C. or about 23 ° C. or about 25 ° C. Also, unless stated otherwise, the temperatures mentioned herein are degrees Celsius.

The term atmospheric pressure is a pressure when it is not particularly reduced or increased, and usually means a pressure of about 1 atmosphere, such as atmospheric pressure.

The thermally conductive composition comprises an oil component. By applying the oil component, the thermally conductive composition can have suitable adhesion performance and insulation properties.

The oil component applicable in the present application is not particularly limited, and known mineral oils, vegetable oils or other synthetic oils may be used.

As the mineral oil in the above, alkanes and / or paraffins may be used, and for example, saturated ester oils and saturated hydrocarbons may be used. As the saturated hydrocarbon, for example, a saturated hydrocarbon having 1 to 30 carbon atoms, 4 to 30 carbon atoms, 8 to 30 carbon atoms, 12 to 30 carbon atoms, or 18 to 26 carbon atoms may be used.

As the vegetable oil, any plant-based oil can be applied without particular limitation, for example, coconut oil, sunflower oil, soybean oil, safflower seed oil. (safflower oil) and the like can be used.

Moreover, as a synthetic oil, it is polyalphaolefin type oil called what is called PAO; Linear alphaolefin oils; Or ester oils such as trimethylolpropane ester; And the like can be used.

In the present application, an appropriate oil may be selected from the above known oils, and in consideration of required physical properties, a liquid oil or a semi-solid oil called grease may be used.

In one example, the oil component may be a polyallphaolefin (PAO) -based oil.

As the PAO oil, a well-known oil can be applied without particular limitation, and for example, an oil having a kinematic viscosity within a predetermined range can be used in consideration of the purpose of the present application.

In one example, the PAO oil may have a kinematic viscosity in accordance with ASTM D445 standard within a range of 3 cSt to 20 cSt at 100 ° C. The dynamic viscosity at 100 ° C. is at least about 3.5 cSt, at least 4 cSt, at least 4.5 cSt, at least 5 cSt, at least 5.5 cSt, at least 6 cSt, at least 6.5 cSt, at least 7 cSt, or at least about 7.5 cSt. , About 18 cSt or less, 16 cSt or less, 14 cSt or less, 12 cSt or less, 10 cSt or less, 9 cSt or less, or about 8.5 cSt or less.

In one example, the PAO oil may have a kinematic viscosity in the range of about 10 cSt to 60 cSt at 40 ° C. according to ASTM D445 standard. The dynamic viscosity at 40 ° C. may, in another example, be at least about 15 cSt, at least 20 cSt, at least 25 cSt, at least 30 cSt, at least 35 cSt, or at least about 40 cSt, at most about 55 cSt, or at most about 50 cSt.

PAO oil having a coin viscosity of the above range may be advantageous for the formation of a thermally conductive composition suitable for the purposes of the present application.

The dynamic viscosity can be measured according to the ASTM D445 standard, and since the manufacturer / seller of PAO oil discloses the dynamic viscosity according to the ASTM D445 standard for each PAO oil as a product specification, You may select an appropriate type.

In addition, the PAO oil may have a weight average molecular weight (Mw) in the range of about 200 to 1,000. In another example, the molecular weight (Mw) may be about 250 or more, about 300 or more, or about 350 or more, or about 900 or less, 800 or less, 700 or less, or about 650 or less. In the present application, the term weight average molecular weight is a standard polystyrene conversion value measured by GPC (Gel Permeation Chromatograph), and may be simply referred to as molecular weight.

For example, the weight average molecular weight can be measured under the following conditions using GPC, and at this time, the measurement result can be converted using standard polystyrene of Agilent system for the production of a calibration curve.

<Weight average molecular weight measurement conditions>

Meter: Gel Permeation Chromatography (Waters Alliance System)

Column: Column: PL Mixed B type

Detector: Refractive index detector

Column flow rate and solvent: 1 mL / min, Solvent: THF (Tetrahydrofuran)

Analytical temperature and measurement volume: 40 ° C., 200 μL

PAO oils having the above characteristics may include, but are not limited to, Durasyn 168 products, Durasyn 164 products, Durasyn 166 products, and the like, distributed under the registered trademark Durasyn.

In another example, the oil component may be an ester oil.

An ester oil is a kind of synthetic oil, and is usually obtained through ester reaction of fatty acid and alcohol. Thus, the ester oil may also be referred to as fatty acid ester.

Fatty acids include caprylic acid, capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, Arachidic acid, Behenic acid, Lignoceric acid, or cerotic acid, and the like, but are not limited thereto.

Examples of the alcohol include known fatty alcohols or polyhydric alcohols having no unsaturated bonds, and examples thereof include saturated monohydric alcohols having 1 to 32 carbon atoms or dihydric or higher polyhydric alcohols. The carbon number of the saturated monohydric alcohol or polyhydric alcohol is, in another example, 4 or more, 8 or more, 12 or more, 16 or more, 20 or more, 24 or more or 28 or more, or 28 or less, 24 or less, 20 or less, 16 or less, 12 Or less, or 8 or less.

Examples of the dihydric or higher polyhydric alcohol include alkylene glycols such as ethylene glycol and propylene glycol, glycerol, glycerin, erythritol, threitol, arabitol, xylitol, and ribitol. (Ribitol), mannitol, sorbitol, and galactitol. Fuctitol, Iditol, Inositol, Volemitol, Isomalt, Maltitol, Lactitol, Maltotriitol, Maltoteitol Tol (Maltotetraitol), trimethylolpropane or polyglycitol (Polyglycitol) and the like can be exemplified, but is not limited thereto.

Through the use of the polyalphaolefin-based oil or ester-based oil it is possible to effectively implement the properties suitable for the intended use.

The thermally conductive composition may also include a thermally conductive filler as a filler. Through such a filler, the thermally conductive composition may exhibit appropriate thermal conductivity and insulation properties.

As used herein, the term thermally conductive filler means a material having a thermal conductivity of about 1 W / mK or more, 5 W / mK or more, 10 W / mK or more, or about 15 W / mK or more. The thermal conductivity of the thermally conductive filler may be about 400 W / mK or less, 350 W / mK or less or about 300 W / mK or less.

In one example, the filler may be a low hardness filler. Such a low hardness filler can prevent or minimize damage to the case or module. For example, a filler having a Mohs hardness of about 5 or less, 4.5 or less, or about 4 or less may be used as the filler. In another example, the Mohs' hardness may be about 1 or more, 1.5 or more, or about 2 or more.

The type of thermally conductive filler may be a ceramic filler in consideration of insulation and the like. For example, nitride particles such as aluminum nitride, boron nitride, silicon nitride and the like; Metal hydroxide particles such as aluminum hydroxide (Al (OH) ₃ ), aluminum hydroxide oxide (AlO (OH)), magnesium hydroxide (Mg (OH) ₂ ), and the like; Or metal oxide particles such as beryllium oxide (BeO), aluminum oxide (Al ₂ O ₃ ), magnesium oxide (MgO) or calcium oxide (CaO); Fillers such as may be used. In addition, if insulation properties can be ensured, application of a carbon filler such as SiC or graphite may also be considered. Fillers include the above-mentioned nitride particles to ensure proper insulation, thermal conductivity and hardness characteristics; Metal hydroxide particles; Or metal oxide particles; but are not limited thereto.

The form or ratio of the filler is not particularly limited, and may be selected in consideration of the viscosity, sedimentation potential, heat resistance or thermal conductivity, insulation, filling effect or dispersibility of the thermal conductive composition.

In general, the larger the size of the filler, the higher the viscosity of the thermally conductive composition and the higher the possibility that the filler will settle. In addition, the smaller the size, the higher the heat resistance tends to be. Therefore, in consideration of the above-mentioned, an appropriate kind of filler may be selected, and if necessary, two or more fillers may be used. In addition, it is advantageous to use a spherical filler in consideration of the filling amount, but fillers in the form of a needle or plate may be used in consideration of the formation of a network or conductivity.

In one example, the average particle diameter of the thermally conductive filler may be in the range of 0.001 μm to 80 μm. In another example, the average particle diameter of the filler may be about 0.01 μm, 0.1 μm, 0.5 μm, 1 μm, 2 μm, 3 μm, 4 μm, 5 μm, or about 6 μm or more. In another example, the average particle diameter of the filler is about 75 μm or less, 70 μm or less, 65 μm or less, 60 μm or less, 55 μm or less, 50 μm or less, 45 μm or less, 40 μm or less, 35 μm or less, 30 μm or less, 25 μm or less, 20 μm or less, 15 μm or less, 10 μm or less, or about 5 μm or less.

The proportion of the filler included in the thermally conductive composition may be selected in consideration of the above-described properties. For example, the filler may be included in the range of about 50 parts by weight to 3,000 parts by weight relative to 100 parts by weight of the oil component of the thermally conductive composition. The weight part of the filler in another example is about 100 parts by weight or more, 150 parts by weight or more, 200 parts by weight or more, 250 parts by weight or more, 300 parts by weight or more, 350 parts by weight or more, 400 parts by weight or more, 500 parts by weight or more, 550 It can be at least 600 parts by weight, at least 600 parts by weight, at least 650 parts by weight, at least 700 parts by weight, at least 800 parts by weight, at least 900 parts by weight, at least 1,000 parts by weight or at least about 1,100 parts by weight, or at least about 2800 parts by weight, at least 2600 parts by weight. Up to 2400 parts by weight, up to 2200 parts by weight, up to 2000 parts by weight, up to 1800 parts by weight, up to 1600 parts by weight or about 1400 parts by weight or less. Therefore, the proportion of the filler can be adjusted according to the above contents.

In the thermally conductive composition in the present application, a dispersant may also be applied. Such a dispersant may be applied in consideration of the dispersibility of the above-mentioned thermally conductive filler. That is, a metal hydroxide or the like may be selected from the thermally conductive fillers in consideration of the above-described thermal conductivity, insulation properties, low wear properties, and the like, and these fillers are often hydrophilic. On the other hand, since the oil component included in the thermally conductive composition is mainly hydrophobic, a dispersant may be applied to secure proper dispersibility.

By selecting a suitable kind as a dispersant, it is possible to provide a thermally conductive composition having excellent physical properties, particularly excellent physical properties including the above-mentioned compression flow.

In one example, the thermally conductive composition may use a compound including a carboxyl group and an amine group as a component that serves as a dispersant.

In one example, a compound represented by the following Formula 1 may be used as the compound including the carboxyl group and the amine group.

[Formula 1]

In Formula 1, R ₁ is an amino acid residue or an alkyl group, R ₂ is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and R ₃ is an alkyl group or alkenyl group having 5 to 30 carbon atoms.

The amino acid residue of R _{1 in} the amino acid except for the carboxyl group (COOH) and amino group (NH ₂ ) except for the hydrogen (H) of one of the side chains bonded to the carbon atom. For example, glycine (Glycine) is R ₁ is H, alanine (Alanine) is R ₁ is CH ₃ , Valine (Valine) is R ₁ is CH (CH ₃ ) ₂ .

The alkyl group of R _{1 may be} an alkyl group having 1 to 20, 1 to 16, 1 to 12, 1 to 8 or 1 to 4 carbon atoms.

In the above, R ₂ may be a linear or branched alkyl group having 1 to 4 carbon atoms. In one example R ₂ may be methyl or ethyl.

In the above, R ₃ may be a linear or branched alkyl or alkenyl group having 5 to 30 carbon atoms, 6 to 28 carbon atoms, 7 to 26 carbon atoms, 8 to 25 carbon atoms, 9 to 24 carbon atoms, and 11 to 22 carbon atoms.

Compounds satisfying Formula 1 include, in one embodiment, cocoyl sarcosine, lauroyl sarcosine, myristoyl sarcosine, and oleoyl sarcosine. Or stearoyl sarcosine, but is not limited thereto.

On the other hand, the dispersant may be used alone or in combination with one or more compounds represented by the formula (1) or a compound represented by the formula (1). By appropriately applying such a compound, a thermally conductive composition of desired physical properties can be provided.

For example, the dispersant may be included in the thermally conductive composition in a ratio of about 0.01 to 13 parts by weight based on 100 parts by weight of the filler. The ratio may be, in another example, at least about 0.05 part by weight, at least 0.1 part by weight, at least 0.2 part by weight, at least 0.3 part by weight, or at least about 0.4 part by weight, or about 13 parts by weight, 10 parts by weight, 5 parts by weight or less. 2 parts by weight or less, 1 part by weight or less, 0.9 parts by weight or less, 0.8 parts by weight or less, or about 0.7 parts by weight or less.

The thermally conductive composition may also include an antioxidant. The oil component included in the thermally conductive composition is advantageous to secure proper adhesion performance, insulation performance and reworkability as described above. The oil component is thermally decomposed to increase the viscosity of the thermally conductive composition over time, Falls and crumbles. Therefore, an appropriate antioxidant is needed to suppress this phenomenon. The type of antioxidant that can be applied is not particularly limited, but in the thermally conductive composition system of the present application, phenolic antioxidants or phosphite antioxidants are advantageous, and the two kinds are simultaneously used. It is best to apply.

Phenolic antioxidants that may be applied include alkylated hydroxytoluenes such as butylated hydroxytoluene, alkyl hydroquinones such as t-butyl hydroquinone, and tetrakis [methylene- 3- (3 ', 5'-di-t-butyl-4'-hydroxyphenyl) propionate] methane (tetrakis [methylene-3 (3', 5'-di-tert-butyl-4'-hydroxyphenyl) ) propionate] methane), octadecyl-3- (3 ', 5'-di-t-butyl-4'-hydroxyphenyl) propionate (octadecyl-3 (3', 5'-di-tert-butyl) -4'-hydroxyphenyl) propionate), 2 ', 3'-bis [3- (3', 5'-di-t-butyl-4'-hydroxyphenyl) propionyl] propionohydrazide (2 ', 3'-bis [3- (3 ', 5'-Di-t-butyl-4'-hydroxy-phenyl) propionyl] propionohydrazide), N, N'-hexane-1,6-diylbis [3- (3 , 5-di-t-butyl-4-hydroxyphenylpropionamide (N, N'-Hexane-1,6-diylbis [3- (3,5-di-tert-butyl-4-hydroxyphenylpropionamide)]), Triethylene glycol-bis-3- (3-t-butyl-4-hydroxy-5-methylfe Propionate (triethyleneglycol-bis-3 (3-tert-butyl-4-hydroxy-5-methylphenyl) propionate), thiodiethylenebis [3- (3,5-di-t-butyl-4-hydride) Hydroxyphenyl) propionate (thiodiethylenebis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate]), tris (3,5-di-t-butyl-4-hydroxybenzyl) isocy Anurate (tris (3,5-di-t-butyl-4-hydroxybenzyl) isocyanurate) or 1,3,5-trimethyl-2,4,6-tris (3,5-di-tert-butyl-4- Hydroxybenzyl) benzene (1,3,5-Trimethyl-2,4,6-tris (3,5-di-tert-butyl-4-hydroxybenzyl) benzene) and the like can be exemplified, but is not limited thereto. .

Examples of the phosphite antioxidant include tris (2,4-di-tert-butylphenyl) phosphite or bis (2,4-di-t-butyl Phenyl) pentaerythritol diphosphite (bis (2,4-di-tert-butylphenyl) pentaerythritol diphosphate) and the like can be exemplified, but is not limited thereto.

As mentioned above, although any of said two types of antioxidants may be used as antioxidant, it is good to apply both types from a viewpoint of suppressing a viscosity increase, a color change, etc., especially tetrakis among phenolic antioxidants. [Methylene-3- (3 ', 5'-di-t-butyl-4'-hydroxyphenyl) propionate] methane (tetrakis [methylene-3 (3', 5'-di-tert-butyl-4) It may be appropriate to add additional phosphite antioxidants with '-hydroxyphenyl) propionate] methane).

The ratio of the antioxidant contained in the thermally conductive composition may be selected in consideration of the above-described characteristics, and is not particularly limited.

The thermally conductive composition may include additives which are necessary in addition to the above components.

For example, the thermally conductive composition may include a filler that is not thermally conductive, for example, and may include a filler to secure thixotropy. In this case, the filler need not be thermally conductive, and the ratio is not required to be particularly large as long as appropriate thixotropy is ensured.

The type of filler included in the thermally conductive composition is not particularly limited, but may be, for example, fumed silica, clay, calcium carbonate, or the like. The form or ratio of the filler is not particularly limited, and may be selected in consideration of viscosity, sedimentation potential in the thermally conductive composition, thixotropy, insulation, filling effect or dispersibility, and if necessary, two or more fillers may be used. It may be. In one example, the average particle diameter of the filler may be in the range of about 0.001 μm to about 80 μm. In another example, the average particle diameter of the filler may be about 0.01 μm or more, 0.1 μm or more, 0.5 μm or more, 1 μm or more, 2 μm or more, 3 μm or more, 4 μm or more, 5 μm or more, or about 6 μm or more. In another example, the average particle diameter of the filler is about 75 μm or less, 70 μm or less, 65 μm or less, 60 μm or less, 55 μm or less, 50 μm or less, 45 μm or less, 40 μm or less, 35 μm or less, 30 μm or less, 25 μm or less, 20 μm or less, 15 μm or less, 10 μm or less, or about 5 μm or less.

The proportion of the filler included in the thermally conductive composition may be selected in consideration of the desired thixotropy. For example, the filler may be included in the range of about 100 parts by weight to about 300 parts by weight relative to 100 parts by weight of the oil component.

The thermally conductive composition may be a viscosity modifier such as a thixotropy agent, a diluent, a surface treatment agent or a coupling agent, if necessary, in order to adjust the viscosity, for example to increase or decrease the viscosity or to adjust the viscosity according to shear force. It may further include.

Thixotropy agent can adjust the viscosity according to the shear force. Examples of the thixotropic agent that can be used include fumed silica and the like.

Diluents are used to lower the viscosity, and any one of various kinds known in the art can be used without limitation as long as the diluent is capable of exhibiting such a function.

The surface treatment agent is for surface treatment of the filler introduced into the thermally conductive composition, and various kinds of those known in the art can be used without limitation as long as they can exhibit the above action.

The thermally conductive composition may further comprise a flame retardant or flame retardant aid and the like. As the flame retardant, various flame retardants known in the art may be applied without particular limitation. For example, a solid filler type flame retardant or a liquid flame retardant may be applied. Flame retardants include, for example, organic flame retardants such as melamine cyanurate, inorganic flame retardants such as magnesium hydroxide, and the like, but is not limited thereto.

If the amount of the filler to be filled in the thermally conductive composition is a liquid type flame retardant material (TEP, Triethyl phosphate or TCPP, tris (1,3-chloro-2-propyl) phosphate, etc.) may be used. In addition, a silane coupling agent may be added that can act as a flame retardant synergist.

The present application also relates to an electronic device to which the above-mentioned thermally conductive composition is applied. The thermally conductive composition may be used in electronic devices or microelectronic packages, and may be used to help dissipate heat from a heat source, such as an electronic die or chip, to a heat dissipation device. The electronic device may include at least one heat source and the thermally conductive composition on the heat source.

The present application also relates to a battery pack to which the above-mentioned thermally conductive composition is applied. The battery pack is a pack case; A plurality of battery modules housed in the pack case; And the thermally conductive composition present between the plurality of battery modules or between the case and the battery module.

In the above structure, the battery modules may have a structure electrically connected to each other.

In one example, the battery module is a battery module known from Patent Document 1, which includes a module case including a thermally conductive portion and a plurality of battery cells, and the battery cell has a structure housed in the module case. Can be. The thermally conductive portions of the battery cell and the module case may be in contact with each other through the thermally conductive resin layer. In the present application, the term battery cell refers to one unit secondary battery including an electrode assembly and an exterior member.

Further, in the structure, the thermally conductive composition may be present between the battery pack case and the thermally conductive portion of the module case. In this case, the case of the pack contacting the thermally conductive portion of the module case through the thermally conductive composition may also be a thermally conductive portion.

Contacting in the above means thermal contact as disclosed in Patent Document 1.

The structure of the battery module as described above is specifically disclosed in Patent Document 1, and the same may be applied to the present specification.

That is, the module case may include at least a side wall and a bottom plate forming an inner space in which the battery cells can be accommodated. The module case may further include a top plate for sealing the inner space. The side wall, the lower plate and the upper plate may be integrally formed with each other, or separate sidewalls, the lower plate and / or the upper plate may be assembled to form the module case. The shape and size of the module case is not particularly limited and may be appropriately selected according to the use, the shape and the number of battery cells housed in the internal space.

FIG. 1 is a diagram showing an exemplary module case 10 and is an example of a box-shaped case 10 including one bottom plate 10a and four sidewalls 10b. As shown in FIG. 1, the module case 10 may further include a top plate 10c that seals the internal space.

2 and 3 are schematic views of the module case 10 of FIG. 1 in which the battery cells 20 are housed, respectively, observed from the top and side surfaces thereof. 3, the thermal conductive resin layer 30 is also shown, and the guiding part 10d which guides the mounting of a battery cell is also shown. In the structure as shown in FIG. 3, when the lower plate 10a of the module case is the above-described thermally conductive portion, heat generated in the battery cell 20 is transferred to the lower plate 10a through the resin layer 30 to be released. Can be.

Therefore, in this case, as shown in FIG. 4, the battery module 100 as shown in FIGS. 2 and 3 is stored in the case 200 of the plurality of battery packs to form a battery pack, and the thermally conductive composition 300 is formed. In the case where the case portion of the battery pack that is in contact with the battery pack is made thermally conductive, as shown in FIG. 4, excellent heat dissipation characteristics can be ensured by passing the cooling water CW through the lower portion of the battery pack.

Therefore, the module case or the battery pack case may be a thermally conductive case. The term thermally conductive case means a case in which the thermal conductivity of the entire case is about 10 W / mk or more, or at least includes a portion having such thermal conductivity. For example, at least one of the above-described side wall, the bottom plate and the top plate and the battery pack case may have the above-described thermal conductivity. In another example, at least one of the side wall, the bottom plate and the top plate and the battery pack case may include a portion having the thermal conductivity.

The thermal conductivity of the top plate, bottom plate or side wall, bater pack case or thermally conductive portion of the thermally conductive module case is, in another example, about 20 W / mk or more, 30 W / mk or more, 40 W / mk or more, 50 W /. mk or more, 60 W / mk or more, 70 W / mk or more, 80 W / mk or more, 90 W / mk or more, 100 W / mk or more, 110 W / mk or more, 120 W / mk or more, 130 W / mk or more , At least 140 W / mk, at least 150 W / mk, at least 160 W / mk, at least 170 W / mk, at least 180 W / mk, at least 190 W / mk or at least about 195 W / mk. The higher the thermal conductivity is, the more advantageous it is in terms of heat dissipation characteristics of the module, and the upper limit thereof is not particularly limited. In one example, the thermal conductivity is about 1,000 W / mK or less, 900 W / mk or less, 800 W / mk or less, 700 W / mk or less, 600 W / mk or less, 500 W / mk or less, 400 W / mk or less, It may be less than or equal to 300 W / mk or about 250 W / mK. The kind of material which exhibits the above thermal conductivity is not specifically limited, For example, metal materials, such as aluminum, gold, silver, tungsten, copper, nickel, or platinum, etc. are mentioned. The module case may be entirely made of such a thermally conductive material, or at least a part of the module case may be a portion of the thermally conductive material. Accordingly, the module case may have a thermal conductivity in the above-mentioned range, or may include at least a portion having the above-mentioned thermal conductivity.

In the above structure, the type of battery cell accommodated in the module case is not particularly limited, and various known battery cells may be applied. In one example, as described in Patent Document 1, a pouch-type battery cell may be used.

The kind of the thermally conductive resin layer included in the battery module in the above structure is not particularly limited, and a resin layer which may be the adhesive layer described in Patent Document 1 may be used.

That is, the resin layer may be an adhesive layer, and the adhesive force of the resin layer is about 150 gf / 10 mm or more, 200 gf / 10 mm or more, 250 gf / 10 mm or more, 300 gf / 10 mm or more, 350 gf / 10 mm or more or about It may be 400 gf / 10mm or more. The said adhesive force is measured about an aluminum pouch according to the system disclosed by patent document 1. The upper limit of the adhesive force of the resin layer is not particularly limited, and for example, about 2,000 gf / 10 mm or less, 1,500 gf / 10 mm or less, 1,000 gf / 10 mm or less, 900 gf / 10 mm or less, 800 gf / 10 mm or less, 700 gf 10 mm or less, 600 gf / 10 mm or less, or about 500 gf / 10 mm or less.

In addition, the resin layer is a thermally conductive resin layer, the thermal conductivity is about 1.5 W / mK or more, 2 W / mK or more, 2.5 W / mK or more, 3 W / mK or more, 3.5 W / mK or more or about 4 W can be greater than / mK. The thermal conductivity is about 50 W / mK or less, 45 W / mk or less, 40 W / mk or less, 35 W / mk or less, 30 W / mk or less, 25 W / mk or less, 20 W / mk or less, 15 W / mk, 10 W / mK or less, 5 W / mK or less, 4.5 W / mK or less, or about 4.0 W / mK or less. As described above, when the resin layer is a thermally conductive resin layer, the lower plate, the upper plate, and / or the sidewall to which the resin layer is attached may be 10 W / mK or more. The thermal conductivity of a resin layer is a numerical value measured according to ASTMD5470 standard or ISO 22007-2 standard, for example. The manner in which the thermal conductivity of the resin layer is in the above range is not particularly limited. For example, the thermal conductivity of a resin layer can be adjusted using the filler which has thermal conductivity as a filler contained in a resin layer.

The thermal resistance of the resin layer or the battery module to which the resin layer is applied in the battery module is about 5 K / W or less, 4.5 K / W or less, 4 K / W or less, 3.5 K / W or less, 3 K / W or less, or about 2.8 K / W or less. When adjusting the resin layer or the battery module to which the resin layer is applied such that the thermal resistance of the range appears, excellent cooling efficiency or heat radiation efficiency can be ensured. The method of measuring the thermal resistance is not particularly limited. For example, it can measure according to ASTM D5470 standard or ISO 22007-2 standard.

The resin layer is also a thermal shock test, for example, a thermal shock test that repeats the cycle 100 times with one cycle of maintaining at a low temperature of about -40 ° C. for 30 minutes and then raising the temperature to 80 ° C. for 30 minutes It may be required to be formed so that it may later be detached from the module case or battery cell of the battery module, or peeled off or cracked. For example, when the battery module is applied to a product that requires a long warranty period (about 15 years or more in the case of an automobile) such as an automobile, the above level of performance may be required to ensure durability.

The resin layer may be an electrically insulating resin layer. By the resin layer exhibiting electrical insulation in the above-described structure, the performance of the battery module can be maintained and stability can be ensured. The electrically insulating resin layer has an insulation breakdown voltage measured in accordance with ASTM D149 of about 3 kV / mm or more, 5 kV / mm or more, 7 kV / mm or more, 10 kV / mm or more, 15 kV / mm or more, or about 20 kV / mm or more. The higher the numerical value of the dielectric breakdown voltage, the resin layer is not particularly limited to exhibit excellent insulating properties, but considering the composition of the resin layer, it is about 50 kV / mm or less, 45 kV / mm or less, 40 kV / mm or less. , 35 kV / mm or less or about 30 kV / mm or less. The dielectric breakdown voltage as described above can also be controlled by controlling the insulation of the resin component of the resin layer. For example, the dielectric breakdown voltage can be adjusted by applying an insulating filler in the resin layer. Generally, among the thermally conductive fillers, the ceramic filler as described later is known as a component capable of ensuring insulation.

As the resin layer, a flame retardant resin layer may be applied in consideration of stability. As used herein, the term flame retardant resin layer may refer to a resin layer having a V-0 rating in a UL 94 V Test (Vertical Burning Test). This ensures stability against fire and other accidents that may occur in the battery module.

The resin layer may have a specific gravity of about 5 or less. The specific gravity may be about 4.5 or less, 4 or less, 3.5 or less, or about 3 or less in another example. The resin layer exhibiting specific gravity in this range is advantageous for the production of a lighter battery module. The lower the specific gravity is, the more advantageous the weight of the module is. Therefore, the lower limit thereof is not particularly limited. For example, the specific gravity may be about 1.5 or more or about 2 or more. In order for the resin layer to exhibit specific gravity in the above range, components added to the resin layer may be adjusted. For example, when the filler is added, a filler capable of securing a desired thermal conductivity even at a low specific gravity as much as possible, that is, a filler having a low specific gravity or a surface-treated filler may be used.

The resin layer may have a ratio of nonvolatile content of about 90 wt% or more, 95 wt% or more, or about 98 wt% or more. In the above, the nonvolatile component and its ratio may be defined in the following manner. That is, the non-volatile portion may be defined as the non-volatile content of the remaining portion after maintaining the resin layer at 100 ° C for about 1 hour, and thus the ratio is about 1 hour at the initial weight of the resin layer and the 100 ° C. It can measure based on the ratio after holding.

The resin layer as described above can be formed by blending a thermally conductive filler with the resin component as disclosed in Patent Document 1. Examples of the resin component that can be applied include acrylic resins, epoxy resins, urethane resins, olefin resins, urethane resins, EVA (Ethylene vinyl acetate) resins, silicone resins, precursors of the resins, and the like. The thing of what was disclosed by patent document 1, the thing contained in the said heat conductive composition, etc. can be used for a heat conductive filler.

The present application provides a thermally conductive composition. In the present application, it is possible to provide a thermally conductive composition that is applied to various applications and has appropriate adhesive properties, heat dissipation properties, thermal conductivity, reworkability, storage stability, insulation properties, storage stability, and durability.

1 is a diagram illustrating an exemplary module case.
2 and 3 are views illustrating a form in which a battery cell is accommodated in a module case.
4 is a diagram schematically showing the structure of a battery pack.
5 is a schematic diagram showing a manner of measuring the compression flow.

Hereinafter, the battery module of the present application will be described with reference to Examples and Comparative Examples, but the scope of the present application is not limited by the scope given below.

1. Dispersibility Assessment Method

The dispersibility of the thermally conductive composition was evaluated by visual observation of the uniform mixing of each component of the thermally conductive composition according to the following criteria.

<Evaluation Criteria>

(Circle): When a filler waste is not observed when mixing the components of a thermally conductive composition with a paste mixer, and a thermally conductive composition exists in the soft state.

(Triangle | delta): When the component of a heat conductive composition is mixed with a paste mixer, the filler adheres to the wall surface of a container, and when a large amount of filler falls when a wall surface is rubbed with a spatula.

X: When mixing the components of the thermally conductive composition with the Paster Mixer, the filler is not properly mixed, and the oral grains formed by the fillers are observed clearly.

2. Compression Flow

Compression flow was measured using an ARES instrument having a cylindrical configuration. As shown in Fig. 5, a thermally conductive composition is placed between two ARES cylindrical configurations (diameter of bottom surface: about 8 mm, denoted by an 8 mm cylinder in the drawing), and the cylindrical configuration The interval between the livers was maintained at about 3 mm. Thereafter, the thermally conductive composition protruding to the side as shown in the figure was removed to form a cylindrical shape. The force applied is then measured while pressing up and down at a rate of about 1 mm / s until the height of the thermally conductive composition (the spacing between the cylindrical configurations) is about 0.3 mm, and the force is applied when the height is about 0.5 mm. It measured and set it as a compression flow.

3. Evaluation method of thermal stability

When the change in the compression flow (B) after leaving for 24 hours in an oven at about 150 ° C. is less than 10% compared to the compression flow (A) before leaving for 24 hours in an oven at 150 ° C., the thermal conductive composition can be evaluated as having thermal stability. have. The change C of the compression flow can be obtained by the following equation.

Change in compression flow (C) = (B-A) / A * 100

Example 1.

Thermally conductive composition: PAO (Polyalphaoleffin) oil (INEOS, Durasyn 168) as an oil component, aluminum hydroxide (Al (OH) ₃ ) having a modal hardness of about 2.5 to 3.5 as a filler, a carboxyl group and a dispersant component Amine-containing compounds (N-oleoyl sarcosine) (NOF, ESLEAM 221P) and antioxidants (Tetrakis (methylene-3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate) methane and Tris (2 Mixture of (4-di-tert-butylphenyl) phophite) (mixed weight ratio: 2: 4.7 (Tetrakis (methylene-3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate)) methane: Tris (2 , 4-di-tert-butylphenyl) phophite)) was combined in a weight ratio (oil: filler: dispersant: antioxidant) of 16: 221: 1: 0.34 to prepare a thermally conductive composition.

Comparative Example 1.

A thermally conductive composition was prepared in the same manner as in Example 1, except that a fatty acid compound (Sigma-Aldrich, Oleic acid) was used as the dispersant component.

Comparative Example 2.

A thermally conductive composition was prepared in the same manner as in Example 1, except that a titanium compound (BORICA, CP-219) was used as the dispersant component.

Comparative Example 3.

A thermally conductive composition was prepared in the same manner as in Example 1 except that a titanium compound (BORICA, CP-317) was used as the dispersant component.

Comparative Example 4.

A thermally conductive composition was prepared in the same manner as in Example 1, except that a titanium compound (BORICA, CP-318) was used as the dispersant component.

Comparative Example 5.

A thermally conductive composition was prepared in the same manner as in Example 1 except that a silane compound (EVONIK, TEGOPREN 6875) was used as the dispersant component.

Evaluation results for the thermally conductive composition are summarized in Table 1 below.

Dispersibility Compression flow (gf) Thermal stability (%) Example ○ 600 8.3 Comparative Example 1 X - - Comparative Example 2 △ More than 3000 - Comparative Example 3 △ More than 3000 - Comparative Example 4 X - - Comparative Example 5 X - - In the case of Comparative Examples 1, 4 and 5, it was impossible to measure the compression flow and thermal stability because proper dispersion was not achieved.
In the case of Comparative Examples 2 and 3, the compression flow was not more than 3000 because the thermal stability evaluation was unnecessary.

10: module case
10a: bottom plate
10b: sidewall
10c: top plate
10d: guiding part
20: battery cell
30: resin layer
100: battery module
200: battery pack case
300: thermally conductive composition

Claims (16)

Oil component; filler; And dispersants,
The dispersant is a thermally conductive composition that is a compound containing a carboxyl group and an amine group. The thermally conductive composition according to claim 1, which is a grease type composition. The thermally conductive composition of claim 1 which is uncured. The thermally conductive composition of claim 1, wherein the press flow is 700 gf or less. The thermally conductive composition of claim 1, wherein the oil component is synthetic oil, mineral oil or vegetable oil. The thermally conductive composition of claim 1, wherein the filler has a thermal conductivity of at least 1 W / mK. The thermally conductive composition of claim 1, wherein the filler has a Mohs hardness of 5 or less. The thermally conductive composition of claim 1, wherein the filler is metal hydroxide, metal oxide or nitride particles. The thermally conductive composition according to claim 1, wherein the filler is included in a ratio within the range of 500 to 2,000 parts by weight based on 100 parts by weight of the oil component. The thermally conductive composition according to claim 1, wherein the compound containing a carboxyl group and an amine group is represented by the following Chemical Formula 1.
[Formula 1]

In Formula 1, R ₁ is an amino acid residue or an alkyl group, R ₂ is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and R ₃ is an alkyl group or alkenyl group having 5 to 30 carbon atoms. The compound comprising a carboxyl group and an amine group is Cocoyl sarcosine, Lauroyl sarcosine, Myristoyl sarcosine, Oleoyl sarcosine And stearoyl sarcosine (Stearoyl Sarcosine) A thermally conductive composition comprising any one or more. The thermally conductive composition of claim 1, wherein the dispersant is included in an amount of 0.01 to 13 parts by weight based on 100 parts by weight of the filler. An electronic device comprising the thermally conductive composition of claim 1 on at least one heat source and at least one heat source. Pack case; A plurality of battery modules housed in the pack case; And the thermally conductive composition of claim 1 present between the plurality of battery modules or between the case and the battery module. The battery module of claim 14, wherein the battery module includes a module case including a thermally conductive portion having a thermal conductivity of 10 W / mk or more, and a plurality of battery cells, wherein the battery cells are housed in the module case. And the thermally conductive portion of the module case is in thermal contact with a thermally conductive resin layer having a thermal conductivity of 1.5 W / mK or more. The battery of claim 15, wherein the battery pack includes a thermally conductive portion having a thermal conductivity of 10 W / mk or more, wherein the thermally conductive portion of the battery module and the thermally conductive portion of the battery pack are in thermal contact with each other through the thermally conductive composition. pack.

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