KR20190089586A - Gap Filler - Google Patents

Abstract

The present application provides a gal filler and uses thereof. In the present application, it is possible to provide a filler which is applied to various applications and has appropriate adhesive properties, heat dissipation properties, thermal conductivity, reworkability, storage stability, insulation properties, storage stability, and durability.

Description

{Gap Filler}

The present application is directed to a gap filler.

A material capable of filling the gap is required in various fields, and in some cases, a gap filling material having thermal conductivity is required.

For example, a gap filler having thermal conductivity may be required in the process of manufacturing a 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 typical example thereof is a lithium secondary battery. A structure in which a plurality of such single secondary cells (hereinafter referred to as battery cells) are electrically connected and housed in a case is referred to as a battery module. For example, in Patent Document 1, And a battery module having excellent heat dissipation characteristics and energy efficiency relative to volume.

In applications where a higher output is required, a plurality of such battery modules are also electrically connected to each other to be housed in a case or the like, thereby constituting a so-called battery pack. In this way, a gap filler may be required between the battery module and the battery module and / or between the battery module and the case of the battery pack in the process of implementing the battery pack.

Korean Patent Publication No. 2016-0105354

The present application provides a gap filling material and its use.

The gap filling material of the present application comprises at least an oil component; And a thermally conductive filler. The gap filling material of the present application can be used for various purposes. As will be described later, the gap filling material can be used in a battery pack constructed by housing a plurality of battery modules in a case, and / And can be positioned between the case and the battery module.

The physical properties required for the gap filler as described above are such that proper adhesiveness is maintained so that a plurality of battery modules can be effectively retained while maintaining a constant gap and at the same time the module can be separated and reattached in the assembling process of the battery pack (Such as abrasion resistance), insulation properties, storage stability, and the like, which can not be damaged by the case or module, Durability such that the above characteristics can be stably maintained for a long period of time, and the gap filler of the present application can stably satisfy the above characteristics.

The gap filler of the present application may be an uncured type. Uncured type means that there is no component capable of causing a curing reaction in the filler. It is advantageous in securing reworkability among the above-mentioned required properties that the filler is of the uncured type.

The gap filler of the present application comprises an oil component. By applying an oil component, the filler can have suitable adhesion properties and insulation properties.

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

As the mineral oil, alkane and / or paraffin, mineral oil and the like can be used. For example, saturated ester oil and saturated hydrocarbon can be used . As the saturated hydrocarbon, for example, saturated hydrocarbons having 1 to 30 carbon atoms, 4 to 30 carbon atoms, 8 to 30 carbon atoms, 12 to 30 carbon atoms, and 18 to 26 carbon atoms can be used.

The vegetable oil is not particularly limited as long as it is a plant-based oil. Examples of the vegetable oil include canola oil, moroccan oil, caster oil, contse seed oil, olive oil, coconut oil coconut oil, sunflower oil, soybean oil, safflower oil and the like can be used.

As the synthetic oil, a polyalphaolefin oil called so-called PAO, an ester oil such as an insulating oil or trimethylpropane ester, and the like can be used.

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

The filler may also include a thermally conductive filler as a filler. These fillers allow the filler to exhibit proper thermal conductivity and insulation properties.

The term thermally conductive filler in the present application means a material having a thermal conductivity of at least about 1 W / mK, at least about 5 W / mK, at least about 10 W / mK, or at least about 15 W / mK. The thermal conductivity of the thermally conductive filler may be about 400 W / mK or less, about 350 W / mK or less, or about 300 W / mK or less.

When the measured temperature and / or pressure affects the physical properties of the physical properties mentioned in the present specification, the physical properties refer to physical properties measured at normal temperature and / or normal pressure, unless otherwise specified.

In the present application, the term ambient temperature is a natural, non-warming or non-warming temperature, for example, any temperature within the range of about 10 ° C to 30 ° C, or a temperature of about 25 ° C or 23 ° C have. Unless otherwise noted, units of temperature are in degrees Celsius.

In the present application, the term atmospheric pressure is a pressure at which the pressure is not particularly reduced or increased, and may be about one atmosphere, usually atmospheric pressure.

The kind of the thermally conductive filler is not particularly limited, but a ceramic filler can be applied in consideration of insulation and the like. For example, particles such as alumina, aluminum nitride, boron nitride, silicon nitride, SiC or BeO, aluminum hydroxide (Al (OH) ₃ ), aluminum hydroxide And metal hydroxides such as aluminum hydroxide oxide (AlO (OH) 2) and magnesium hydroxide (Mg (OH ₂ )). Further, if the insulating property can be secured, application of a carbon filler such as graphite can be considered. The shape and ratio of the filler are not particularly limited and may be selected in consideration of the viscosity of the filler, the possibility of settling, the thermal resistance or thermal conductivity, the insulating property, the filler effect or the dispersibility. Generally, the larger the filler size, the lower the viscosity of the filler. The higher the ratio, the higher the viscosity. The lower the viscosity, the less spherical the filler is. Therefore, a suitable type of filler can be selected in consideration of the above points, and two or more kinds of fillers can be used if necessary. In consideration of the filling amount, it is advantageous to use a spherical filler. However, in consideration of formation of a network and conductivity, a filler in the form of a needle or a plate may be used. In one example, the average particle diameter of the thermally conductive filler may be in the range of 0.001 to 80 mu m. In other examples, the average particle diameter of the filler may be 0.01 μm or more, 0.1 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 size of the filler may be about 75 탆 or less, about 70 탆 or less, about 65 탆 or less, about 60 탆 or less, about 55 탆 or less, about 50 탆 or less, about 45 탆 or less, About 35 μm or less, about 30 μm or less, about 25 μm or less, about 20 μm or less, about 15 μm or less, about 10 μm or less, or about 5 μm or less.

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

As the filler, the aforementioned metal hydroxide particles, aluminum nitride (BN), boron nitride (BN) and silicon nitride nitride particles can be used for securing appropriate insulating properties, thermal conductivity and hardness characteristics. It is not.

The proportion of the filler contained in the filler can be selected in consideration of the above-mentioned characteristics. For example, the filler may be included in the range of about 50 to 4,000 parts by weight based on 100 parts by weight of the oil component of the filler. In another embodiment, the weight of the filler is at least about 100 parts by weight, at least about 150 parts by weight, at least about 200 parts by weight, at least about 250 parts by weight, at least about 300 parts by weight, at least about 350 parts by weight, at least about 400 parts by weight, At least about 500 parts by weight, at least about 550 parts by weight, at least about 600 parts by weight, at least about 650 parts by weight, at least about 700 parts by weight, at least about 750 parts by weight, at least about 800 parts by weight, at least about 850 parts by weight, at least about 900 Or about 950 parts by weight or greater, about 3500 parts by weight or less, about 3000 parts by weight or less, about 2500 parts by weight or less, about 2000 parts by weight or about 1800 parts by weight or less.

The filler may also comprise an antioxidant. As described above, the oil component contained in the filler is advantageous in ensuring proper bonding performance, insulation performance and reworkability, and it has a characteristic of pyrolysis that increases the viscosity of the filler with time and deteriorates the adhesive strength, do. Therefore, appropriate antioxidants are needed to suppress this phenomenon. The type of the antioxidant that can be applied is not particularly limited. In the filler system of the present application, a phenolic antioxidant, an amine antioxidant (for example, a hindered amine light stabilizer), a thioester Based antioxidant or a phosphite antioxidant is advantageous, and it is most preferable to apply the above two types simultaneously.

Phenolic antioxidants that may be applied include alkylated hydroxytoluene, such as butylated hydroxytoluene, alkyl hydroquinone, such as tert-butyl hydroquinone, tetrakis [methylene- (3 ', 5'-di-tert-butyl-4'-hydroxyphenyl) methane (tetrakis [methylene-3 ) propionate] methane) (CAS No .: 6683-19-8); (3 ', 5'-di-tert-butyl-4'-hydroxyphenyl) propionate (octadecyl- propionate) (CAS No .: 2082-79-3); (3 ', 5'-di-t-butyl-4'-hydroxyphenyl) propionyl] propionohydrazide (2', 3'-bis [3- ', 5'-Di-t-butyl-4'-hydroxy-phenyl) propionyl] propionohydrazide) (CAS No .: 32687-78-8); N, N'-hexane-1,6-diylbis [3- (3,5-di-t-butylphenylacetamide) (3,5-di-tert-butyl-4-hydroxyphenylpropionamide)) (CAS No. 23128-74-7), triethylene glycol- 3-tert-butyl-4-hydroxy-5-methylphenyl) propionate (CAS No. 36443-68-2), 2,2'-thiodiethylenebis [ (3,5-di-tert-butyl-4-hydroxyphenyl) propionate] (CAS No. 41484-35-9), tris (3,5-di-tert-butyl-4-hydroxybenzyl) isocyanurate (tris ) isocyanurate (CAS No .: 27676-62-6), benzenepropanoic acid, 3,5-bis (1,1-dimethylethyl) -4-hydroxy-C7-9-brindidoalkyl ester , 3,5-bis (1,1-dimethylethyl) -4-hydroxy-C7-9-branched alkyl esters (CAS No .: 125643-61-0), 2,2'-ethylidene bis Di-tert-butylphenol) (2,2'-ethylid (3,5-di-tert-butylphenol) (CAS No. 35958-30-6), N, N'-hexamethylene-bis (N, N'-hexamethylene-bis (3,5-di-tert-butyl) -4-hydorxy hydrocinnamamide) (CAS No. 23128-74-7), 4,4'-butylidene Bis (6-tert-butyl-3-methylphenol) (CAS No. 85-60-9), 1,3,5-tris (2,6-dimethyl-3-hydroxy-4-tert-butylbenzyl) isocyanurate was used in place of 1,3,5-tris (2,6- Bis (octylthiomethyl) -o-cresol (CAS No .: 110553-27-0), 1,2-bis (3,6- Bis-3,5-di-tert-butyl-4-hydrocinnamoyl) hydrazine (CAS No. 5-di-tert-butyl-4-hydrocinnamoyl) hydrazine. 32687-78-8), poly (dicyclopentadiene-co-p-cresol) (CAS No. 68610-51-5) or 1,3,5-trimethyl 2,4,6-tris (3,5-di-tert-butyl-4-hydroxybenzyl) benzene (1,3,5-trimethyl- -butyl-4-hydroxybenzyl) benzene (CAS No .: 1709-70-2), and the like, but is not limited thereto.

Examples of the amine antioxidant include 1,6-hexanediamine, N, N'-bis (2,2,6,6-tetramethyl-4-piperidinyl-, 2,4,6-trichloro- 1,3,5-triazine, a reaction product of N-butanamine and N-butyl-2,2,6,6-tetramethyl-4-piperidinamine (1,6-hexanediamine, N, N ' -bis (2,2,6,6-tetramethyl-4-piperidinyl) -copolymer with 2,4,6-trichloro-1,3,5-triazine, reaction products with N-butyl-1-butanamine and N- butyl-2,2,6,6-tetramethyl-4-piperidinamine (CAS No .: 192268-64-7); poly (4-hydroxy-2,2,6,6-tetramethyl- (4-hydroxy-2,2,6,6-tetramethyl-1-piperidine ethanol-alt-1,4-butanedioic acid) (CAS No .: Bis (1,2,2,6,6-pentamethyl-4-piperidyl) sebacate (bis (1,2,2,6,6-pentamethyl-4-piperidyl) sebacate ) (CAS No .: 41556-26-7); bis (2,2,6,6-tetramethyl-4-piperidyl) ) sebacate (CAS No .: 52829-07-9), poly [N, N'-bis (2,2,6,6-tetramethoxy) N, N'-bis (diphenylphosphino) -1,6-hexanediamine-co-2,4-dichloro-6-morpholino- 2,2,6,6-tetramethyl-4-piperidinyl) -1,6-hexanediamine-co-2,4-dichloro-6-morpholino-1,3,5-triazine]) (CAS No .: 82451- 48-7); 2,2,6,6-tetramethyl-4-piperidinyl stearate (CAS No .: 167078-06-0); 2,2,6,6-tetramethyl-4-piperidinyl stearate; 1,6-hexanediamine, N, N'-bis (2,2,6,6-tetramethyl-4-piperidinyl) -, 2,4,6-trichloro-1,3,5- (1,6-hexanediamine, N, N'-bis (2,2,6,6-tetramethyl-4-piperidinyl) -, polymer with 2,4,4-trimethyl- with 2,4,6-trichloro-1,3,5-triazine, reaction products with 2,4,4-trimethyl-2-pentanamine) (CAS No .: 72245-38-6); Or 1,3,5-triazine-2,4,6-triamine, N2, N2'-1,2-ethanediylbis [N- [3- [[4,6- , 2,6,6-pentamethyl-4-piperidinyl) amino] -1,3,5-triazin-2-yl] amino] propyl-N'N'-dibutyl-N'N " (1,2,2,6,6-pentamethyl-4-piperidinyl) (1,3,5-triazine-2,4,6-triamine, N2, N2'-1,2-ethanediylbis [N- Amino] -1,3,5-triazin-2-yl] amino] propyl] -N- [3,6-bis (N-dibutyl-N'N "-bis (1,2,2,6,6-pentamethyl-4-piperidinyl)] (CAS No. 106990-43-6) But is not limited thereto.

As the phosphite antioxidant, the phosphite antioxidant may be tris (2,4-di-tert-butylphenyl) phosphite (CAS No : 31570-04-4), tetrakis (2,4-di-tert-butylphenyl) [1,1'-bisphenyl] -4,4'-diylbis (phosphonite) 4-di-tert-butylphenyl) [1,1'-biphenyl] -4,4'-diylbis (phosphonite) (CAS No. 38613-77-3), tripheylphosphine (CAS No. : 603-35-0), poly (dipropylene glycol) phenyl phosphite (CAS No. 116265-68-0) or bis (2,4-di-t-butylphenyl (2,4-di-tert-butylphenyl) pentaerythritol diphosphate (CAS No .: 97994-11-1) and the like can be exemplified. But is not limited to.

Examples of the thioester-based antioxidant include distearyl thiodipropionate (CAS No. 693-36-7), dilauryl thiodipropionate (CAS No. 1), and the like. : 123-28-4), ditetradecyl 3,3'-thiodipropionate (CAS No. 693-36-7), tridecyl 3- (3-oxo 3-tridecoxypropyl) sulfanylpropanoate (CAS No. 10595-72-9) or pentaerythritol tetrakis (3-oxo-3-tridecoxypropyl) sulfanylpropanoate (Pentaerythritol tetrakis (3-laurylthiopropionate) (CAS No .: 29598-76-3), and the like can be exemplified, but the present invention is not limited thereto.

As described above, any of the antioxidants may be used as the antioxidant, but it may be appropriate to apply a mixture of two or more of the antioxidants from the viewpoint of suppressing increase in viscosity and color change.

In one example, a phenol-based antioxidant and / or an amine-based antioxidant is applied as a primary antioxidant and a phosphite-based antioxidant and / or a thioester-based antioxidant is applied as a secondary antioxidant Can be advantageous.

The proportion of the antioxidant contained in the filler may be selected in consideration of the above characteristics, for example, within a range of about 100 parts by weight or less relative to 100 parts by weight of the oil component. In another embodiment, the ratio is at least about 0.5 parts by weight, at least about 1 part by weight, at least about 1.5 parts by weight, at least about 2 parts by weight, at least about 2.5 parts by weight, or at least about 3 parts by weight, at least about 90 parts by weight, Up to about 80 parts by weight, up to about 70 parts by weight, up to about 60 parts by weight, up to about 50 parts by weight, up to about 40 parts by weight, up to about 30 parts by weight, up to about 20 parts by weight, up to about 10 parts by weight, Or less.

In addition, when the primary and secondary antioxidants are simultaneously applied, the secondary antioxidant may be applied in a proportion of 400 parts by weight or less based on 100 parts by weight of the primary antioxidant. In another embodiment, the ratio of the secondary antioxidant may be at least about 5 parts by weight, at least about 10 parts by weight, at least about 15 parts by weight, at least about 20 parts by weight, at least about 30 parts by weight, at least about 40 parts by weight, at least about 50 parts by weight, At least 70 parts by weight, at least 80 parts by weight, at least 90 parts by weight, at least 100 parts by weight, at least 110 parts by weight, at least 120 parts by weight, at least 130 parts by weight, at least 140 parts by weight, at least 150 parts by weight, 170 parts by weight or more, 180 parts by weight or more, 190 parts by weight or more, about 350 parts by weight or less, 300 parts by weight or less, or 250 parts by weight or less.

The filler may also be a dispersant. Such a dispersant can be applied considering the dispersibility of the above-mentioned thermally conductive filler. That is, metal hydroxide and the like may be selected among the thermally conductive fillers in consideration of the above-mentioned thermal conductivity, insulation property and low abrasion resistance, and these fillers are mostly hydrophilic. On the other hand, since the oil component contained in the filler is mainly hydrophobic, a dispersant can be applied to ensure proper dispersibility.

The kind of the dispersing agent is not particularly limited and may be, for example, sodium stearate, stearic acid, oleic acid, oleylamine, palmitic acid, Dodecanoyl acid and / or isostearic acid may be used.

In the filler system of the present application, in particular, oleic acid, octanoic acid, palmitic acid, stearic acid or linoleic acid, etc. may be used as the dispersing agent, Of fatty acids or oleylamines, such as N, N-dimethyl-1-tetradecaneamine, laurylamine, coconutamine, n-tridecylamine, myristylamine, n-pentadecylamine, Fatty acid amines such as amine, stearylamine, n-nonadecylamine, n-eicosylamine, n-hexecylamine, n-docosylamine, n-tricosylamine or n-pentacosylamine And most suitably both of them can be applied.

The proportion of the dispersant contained in the filler may be selected in consideration of the objective characteristics, for example, in the range of about 0.001 to 30 parts by weight based on 100 parts by weight of the oil component. The ratio may be at least about 0.01 part by weight, at least about 0.1 part by weight, at least about 0.5 part by weight, at least about 1 part by weight, at least about 2 parts by weight, at least about 3 parts by weight, at least about 4 parts by weight, at least about 5 parts by weight, At least 7 parts by weight, at least 8 parts by weight, at least 9 parts by weight or at least 9.5 parts by weight, at least about 28 parts by weight, at most 26 parts by weight, at most 24 parts by weight, at most 22 parts by weight, at most 20 parts by weight, Less than or equal to 16 parts by weight, less than or equal to 14 parts by weight, less than or equal to 12 parts by weight, or less than or equal to 11 parts by weight. When a fatty acid and a fatty acid amine are used at the same time, about 20 to 50 parts by weight of a fatty acid amine may be applied to 100 parts by weight of the fatty acid. The proportion of the fatty acid amine may be at least about 25 parts by weight, or at least about 30 parts by weight, and in other embodiments at least about 45 parts by weight, up to about 40 parts by weight, or up to about 35 parts by weight.

The filler may also contain additives necessary in addition to the above components.

For example, the filler may include a filler that is not thermally conductive depending on the purpose, for example, a filler may be included to secure thixotropy. In this case, the filler need not be thermally conductive, and the proportion thereof is not particularly required as long as adequate thixotropy is ensured.

The type of the filler contained in the filler is not particularly limited, but may be, for example, fumed silica, clay or calcium carbonate. The shape and ratio of the filler are not particularly limited and may be selected in consideration of viscosity, sedimentation potential in the filler, thixotropy, insulating property, filling effect or dispersibility, and two or more fillers may be used if necessary . In one example, the average particle size of the filler may be in the range of 0.001 탆 to 80 탆. In other examples, the average particle diameter of the filler may be 0.01 μm or more, 0.1 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 size of the filler may be about 75 탆 or less, about 70 탆 or less, about 65 탆 or less, about 60 탆 or less, about 55 탆 or less, about 50 탆 or less, about 45 탆 or less, About 35 μm or less, about 30 μm or less, about 25 μm or less, about 20 μm or less, about 15 μm or less, about 10 μm or less, or about 5 μm or less.

The ratio of the filler contained in the filler may be selected in consideration of the desired thixotropy and the like. For example, the filler may be included in the range of about 100 to 300 parts by weight based on 100 parts by weight of the oil component.

The filler may also contain a viscosity modifier such as a thixotropic agent, diluent, dispersant, surface treatment agent or coupling agent for adjusting viscosity, for example, increasing or decreasing viscosity, or adjusting viscosity according to shear force As shown in FIG.

The thixotropic agent can control the viscosity according to shear force. As thixotropic agents that can be used, fumed silica and the like can be exemplified.

The diluent is used for lowering the viscosity, and any of various kinds known in the art can be used without limitation as long as it can exhibit the above-mentioned action.

The surface treatment agent is for surface treatment of the filler introduced into the filler, and any of various kinds known in the art can be used without limitation as long as it can exhibit the above-mentioned action.

The filler may further include a flame retardant or a flame retardant auxiliary. As the flame retardant, various known flame retardants may be applied without particular limitation, and for example, solid phase filler-type flame retardants and liquid flame retardants can be applied. Examples of the flame retardant include organic flame retardants such as melamine cyanurate and the like, inorganic flame retardants such as magnesium hydroxide and the like, but are not limited thereto.

If the amount of filler filled in the filler is large, a liquid type flame retardant (TEP, triethyl phosphate, TCPP, tris (1,3-chloro-2-propyl) phosphate, etc.) may be used. Further, a silane coupling agent capable of acting as a flame retardant may be added.

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

In this structure, the battery modules may be electrically connected to each other.

In one example, the battery module is a battery module known in the above-described Patent Document 1, and 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 . In this case, the thermally conductive portions of the battery cell and the module case may be in contact via a thermally conductive resin layer or a thermally conductive pad (hereinafter collectively referred to as a thermally conductive resin layer).

In addition, in the above structure, the filler may be present between the battery pack case and the thermally conductive portion of the module case. In this case, the pack case contacting the thermally conductive portion of the module case via the filler may be a thermally conductive portion.

Contacting from 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 can be applied to the present invention as well.

That is, the module case may include at least a sidewall and a bottom plate that form an internal space in which the battery cell can be housed. The module case may further include an upper plate sealing the inner space. The side wall, the lower plate, and the upper plate may be integrally formed with each other, or the module case may be formed by assembling separated side walls, a lower plate, and / or an upper plate. The shape and size of the module case are not particularly limited and may be appropriately selected depending on the application, the type and number of battery cells housed in the internal space, and the like.

1 is a view showing an exemplary module case 10 and is an example of a box-shaped case 10 including one lower plate 10a and four side walls 10b. As shown in FIG. 1, the module case 10 may further include an upper plate 10c for sealing the inner space.

2 and 3 are schematic views of the module case 10, 10b, and 10c of FIG. 1, in which the battery cell 20 is housed, from above and from the side, respectively. 3, the thermally conductive resin layer 30 is also shown, and the guiding portion 10d for guiding the mounting of the battery cell is also shown. In the structure shown in FIG. 3, when the lower plate 10c of the module case is the above-described thermally conductive portion, heat generated in the battery cell 20 is transferred to the lower plate 10c through the resin layer 30 and is discharged .

Therefore, in this case, as shown in FIG. 4, a plurality of battery modules 100 as shown in FIGS. 2 and 3 are accommodated in the case 200 of the battery pack to form a battery pack, the filler 300 is disposed When the case portion of the battery pack in contact therewith is made thermally conductive, the cooling water (CW) or the like is passed through the lower portion (CW) of the battery pack as shown in FIG.

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 case as a whole is 10 W / mk or more, or at least a portion having the above-mentioned thermal conductivity is included. For example, at least one of the side wall, the bottom plate, and the top plate and the battery pack case described above may have the thermal conductivity described above. 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, bottom or side wall, battery pack case or thermally conductive portion of the thermally conductive module case is 20 W / mk or more, 30 W / mk or more, 40 W / mk or more, 50 W / mk At least 60 W / mk, at least 70 W / mk, at least 80 W / mk, at least 90 W / mk, at least 100 W / mk, at least 110 W / mk, at least 120 W / 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 195 W / mk. The higher the value of the thermal conductivity is, the more advantageous it is from the viewpoint of the heat dissipation characteristics of the module and the like, and the upper limit is not particularly limited. In one example, the thermal conductivity is about 1000 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 / 300 W / mk or 250 W / mK, but is not limited thereto. There is no particular limitation on the kind of the material exhibiting the thermal conductivity as described above, and examples thereof include metal materials such as aluminum, gold, pure silver, tungsten, copper, nickel or platinum. The module case may be entirely made of the thermally conductive material as described above, or at least a part of the module case may be made of the thermally conductive material. Accordingly, the module case may have at least the above-mentioned range of thermal conductivity, or at least the portion having the aforementioned thermal conductivity.

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

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

That is, the resin layer may be an adhesive layer, and the adhesive strength of the resin layer may be 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 / gf / 10 mm or more. The adhesive force is measured for the aluminum pouch according to the method disclosed in Patent Document 1. [ The upper limit of the adhesive strength of the resin layer is not particularly limited and may be, 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, 600 gf / 10 mm or less, or 500 gf / 10 mm or less.

The resin layer is a thermally conductive resin layer having a thermal conductivity of about 1.5 W / mK or more, about 2 W / mK or more, 2.5 W / mK or more, 3 W / mK or more, 3.5 W / / mK. The thermal conductivity is not more than 50 W / mK, not more than 45 W / mk, not more than 40 W / mk, not more than 35 W / mk, not more than 30 W / mk, not more than 25 W / mk, not more than 20 W / MW or less, 5 W / mK or less, 4.5 W / mK or less, or about 4.0 W / mK or less. When the resin layer is a thermally conductive resin layer as described above, the lower plate, the upper plate and / or the side wall to which the resin layer is attached may have a thermal conductivity of 10 W / mK or more. The thermal conductivity of the resin layer is, for example, a numerical value measured in accordance with ASTM D5470 or ISO 22007-2, or a hot disk method according to ISO 22007-2. The method of setting the thermal conductivity of the resin layer in the above-described range is not particularly limited. For example, the thermal conductivity of the resin layer can be adjusted by using a thermally conductive filler as a filler contained in the resin layer.

The battery module to which the resin layer or the resin layer is applied has a thermal resistance of 5 K / W or less, 4.5 K / W or less, 4 K / W or less, 3.5 K / W or less, 3 K / K / W. When the resin layer or the battery module to which the resin layer is applied is adjusted to exhibit the thermal resistance within such a range, excellent cooling efficiency or heat radiation efficiency can be secured. The method of measuring the thermal resistance is not particularly limited. For example, it can be measured according to the ASTM D5470 standard or the ISO 22007-2 standard.

The resin layer may also be subjected to a thermal shock test, for example, by holding it at a low temperature of about -40 ° C for 30 minutes, then raising the temperature to 80 ° C for 30 minutes, It may be required to be formed such that it may be detached or peeled off from the module case or the battery cell of the battery module later, or no cracks may occur. For example, when the battery module is applied to a product requiring a long warranty period (for example, about 15 years in the case of a car) such as an automobile, the same level of performance may be required to ensure durability.

The resin layer may be an electrically insulating resin layer. In the structure described above, since the resin layer exhibits electrical insulation, the performance of the battery module can be maintained and stability can be ensured. The electrically insulating resin layer preferably has an insulation breakdown voltage of at least about 3 kV / mm, at least about 5 kV / mm, at least about 7 kV / mm, at least 10 kV / mm, at least 15 kV / mm, 20 kV / mm or more. The dielectric breakdown voltage is not particularly limited to a value that the resin layer exhibits good insulation as the numerical value of the breakdown voltage is higher. However, it is preferably about 50 kV / mm or less, 45 kV / mm or less, 40 kV / mm or less , 35 kV / mm or less, and 30 kV / mm or less. The dielectric breakdown voltage as described above can also be controlled by controlling the insulating property of the resin component of the resin layer. For example, the dielectric breakdown voltage can be controlled by applying an insulating filler in the resin layer. In general, among the thermally conductive fillers, a ceramic filler as described later is known as a component capable of ensuring insulation.

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

The resin layer may have a specific gravity of 5 or less. The specific gravity may be 4.5 or less, 4 or less, 3.5 or less, or 3 or less in other examples. The resin layer showing the weight of this range is advantageous for manufacturing a lighter battery module. The lower the specific gravity, the more advantageous the weight of the module is, so the lower limit is not particularly limited. For example, the specific gravity can be about 1.5 or more, or 2 or more. The component added to the resin layer can be adjusted so that the resin layer exhibits a specific weight in the above range. For example, a filler capable of ensuring a desired thermal conductivity even when a filler is added at a low specific gravity, that is, a filler having a low specific gravity, or a method of applying a surface treated filler can be used.

The resin layer may have a non-volatile content of 90 wt% or more, 95 wt% or more, or 98 wt% or more. In the above, the nonvolatile component and the ratio thereof can be defined in the following manner. That is, the nonvolatile portion can define the remaining portion after the resin layer is maintained at 100 ° C for about 1 hour, so that the ratio is the same as the initial weight of the resin layer at 100 ° C for about 1 hour And can be measured based on the ratio after maintenance.

Such a resin layer can be formed by blending a thermally conductive filler with a resin component as disclosed in Patent Document 1. [ As the resin component that can be applied at this time, an acrylic resin, an epoxy resin, a urethane resin, an olefin resin, a urethane resin, an ethylene vinyl acetate (EVA) resin or a silicone resin, , The thermally conductive filler disclosed in Patent Document 1, and the thermally conductive filler included in the filler can be used.

The present application provides a gap filler. In the present application, it is possible to provide a filler which is applied to various uses and has appropriate adhesive properties, heat radiation properties, thermal conductivity, reworkability, storage stability, insulation properties, storage stability and durability.

1 is a view showing an exemplary module case.
Figs. 2 and 3 are views showing a state in which a battery cell is housed in a module case. Fig.
4 is a diagram schematically showing the structure of the battery pack.

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 following range.

1. Thermal conductivity evaluation method

The thermal conductivity of the gap filler was measured by Hot Disk method according to ISO22007-2 standard. Specifically, the sample (gap filler) is placed in a mold having a thickness of about 5 mm, and the thermal conductivity can be measured in the through plane direction by using a hot disk apparatus. As specified in the above standard (ISO 22007-2), the Hot Disk equipment is a device that can check the thermal conductivity by measuring the temperature change (change in electrical resistance) while the sensor having the nickel spiral structure is heated. The thermal conductivity was measured according to the standard.

The thermal conductivity may be measured according to the ASTM D5470 standard in addition to the above method. That is, after placing the filler between two copper bars according to the standard of ASTM D 5470, one of the two copper rods is brought into contact with the heater and the other is brought into contact with a cooler, To keep the temperature constant, and adjust the capacity of the cooler to make a thermal equilibrium state (a temperature change of about 0.1 ° C or less in 5 minutes). (K, unit: W / mK) can be evaluated according to the following equation by measuring the temperature of each copper rod in a thermal equilibrium state. In this method, the pressure applied to the filler during the evaluation of the thermal conductivity is adjusted to about 11 Kg / 25 cm ² , and the thermal conductivity is calculated based on the final thickness when the thickness of the filler is changed during the measurement.

<Thermal Conductivity Formula>

K = (Q x dx) / (A x dT)

(Unit: m), A is the cross-sectional area (unit: m ² ) of the filler, and K is the heat conductivity (W / mK) ), And dT is the temperature difference (unit: K) of the copper rod.

2. How to evaluate the mixture

Whether or not the components of the gap filler were uniformly mixed was visually observed and evaluated according to the following criteria.

<Evaluation Criteria>

◎: When filler particles are mixed with components of gap filler by Paste Mixer, no filler particles are observed, and gap filler exists in a soft state

○: When mixing the components of the gap filler with the Paste Mixer, a small amount of filler is observed attached to the wall of the container. If a small amount of filler falls when the wall is rubbed with the spatula

△: When mixing the components of the gap filling agent with the Paste Mixer, the filler is observed on the wall of the container, and when a large amount of filler is dropped when the wall is rubbed by the spatula

×: When mixing the components of the gap filling agent with the Paste Mixer, if the filler is not properly mixed and the beads in which the fillers are formed are clearly observed,

Example  One.

Mineral oil (Sigma Aldrich, CAS No. 8042-47-5) as an oil component, aluminum hydroxide (Al (OH) ₃ ) having a Mohs hardness of about 2.5 to 3.5 as a thermally conductive filler, 100: 1400: 10 (oil: thermally conductive filler: dispersant) to prepare a gap filler. As the dispersing agent, oleic acid and oleylamine were mixed in a weight ratio of about 75:25 (oleic acid: oleylamine).

Example  2.

A poly-alpha-olefin (PAO) oil (Durasyn 168) as an oil component, an aluminum hydroxide (Al (OH) ₃ ) having a Mohs hardness of about 2.5 to 3.5 as a thermally conductive filler and a dispersant : 1200: 10 (oil: thermally conductive filler: dispersant) to prepare a gap filler. As the dispersing agent, oleic acid and oleylamine were mixed in a weight ratio of about 75:25 (oleic acid: oleylamine).

Comparative Example  One.

Mineral oil (Sigma Aldrich, CAS No. 8042-47-5) as an oil component, aluminum hydroxide (Al (OH) ₃ ) having a Mohs hardness of about 2.5 to 3.5 as a thermally conductive filler, 100: 1000: 10 (oil: thermally conductive filler: dispersant) to prepare a gap filler. In the above, oleylamine alone was used as the dispersing agent.

Comparative Example  2.

Mineral oil (Sigma Aldrich, CAS No. 8042-47-5) as an oil component, aluminum hydroxide (Al (OH) ₃ ) having a Mohs hardness of about 2.5 to 3.5 as a thermally conductive filler, 100: 1000: 10 (oil: thermally conductive filler: dispersant) to prepare a gap filler. As the dispersing agent, octylamine was used alone.

Comparative Example  3.

Mineral oil (Sigma Aldrich, CAS No. 8042-47-5) as an oil component, aluminum hydroxide (Al (OH) ₃ ) having a Mohs hardness of about 2.5 to 3.5 as a thermally conductive filler, 100: 1000: 10 (oil: thermally conductive filler: dispersant) to prepare a gap filler. N, N-dimethyltetradecylamine was used alone as the dispersing agent.

Comparative Example  4.

Mineral oil (Sigma Aldrich, CAS No. 8042-47-5) as an oil component, aluminum hydroxide (Al (OH) ₃ ) having a Mohs hardness of about 2.5 to 3.5 as a thermally conductive filler, 100: 1000: 10 (oil: thermally conductive filler: dispersant) to prepare a gap filler. As the dispersant, oleic acid was used alone.

Comparative Example  5.

A poly-alpha-olefin (PAO) oil (Durasyn 168) as an oil component, an aluminum hydroxide (Al (OH) ₃ ) having a Mohs hardness of about 2.5 to 3.5 as a thermally conductive filler and a dispersant : 1200: 10 (oil: thermally conductive filler: dispersant) to prepare a gap filler. As the dispersing agent, oleic acid was used alone.

The evaluation results of the gap filler are summarized in Table 1 below.

Mixed Thermal conductivity (unit: W / mk) Example 1 ◎ 3.06 Example 2 ◎ 3.17 Comparative Example 1 × - Comparative Example 2 × - Comparative Example 3 × - Comparative Example 4 △ 2.89 Comparative Example 5 ○ 3.13

10, 10a, 10b, 10c: module case
10d: guiding part
20: Battery cell
30: resin layer
100: Battery module
200: Battery pack case
300: gap filler

Claims (15)

Oil component; A thermally conductive filler and a dispersant,
Wherein the dispersing agent comprises a fatty acid and a fatty acid amine. The gap filler according to claim 1, which is an uncured type. The gap filler according to claim 1, wherein the oil component is synthetic oil, mineral oil or vegetable oil. The composition of claim 1 wherein the oil component is selected from the group consisting of ester oils, saturated hydrocarbons, paraffin, coconut oil, sunflower oil, soybean oil, safflower oil, polyalphaolefin oil, mineral oil, paraffin oil, Oil, cotton seed oil or olive oil. The gap filler according to claim 1, wherein the thermally conductive filler is 1 W / mK or more. The thermally conductive filler according to claim 1, wherein the thermally conductive filler is a filler having a Mohs hardness of 5 or less The gap filler according to claim 1, wherein the thermally conductive filler is a metal hydroxide or nitride particle. The gap filler according to claim 1, wherein the thermally conductive filler is contained in a proportion within a range of 50 to 2,000 parts by weight based on 100 parts by weight of the oil component. The gap filler according to claim 1, wherein the fatty acid is oleic acid, octanoic acid, palmitic acid, stearic acid or linoleic acid. The method according to claim 1, wherein the fatty acid amine is selected from the group consisting of oleylamine, N, N-dimethyl-1-tetradecaneamine, laurylamine, coconutamine, n-tridecylamine, myristylamine, n-pentadecylamine, A gap which is an amine, n-heptadecylamine, stearylamine, n-nonadecylamine, n-eicosylamine, n-hexecylamine, n-docosylamine, n-tricosylamine or n-pentacosylamine Filler. The gap filler according to claim 1, comprising 0.001 to 30 parts by weight of a dispersing agent based on 100 parts by weight of the oil component. The gap filler according to claim 1, wherein the dispersing agent comprises 20 to 50 parts by weight of fatty acid amine relative to 100 parts by weight of fatty acid. Pack case; A plurality of battery modules housed in the pack case; And the filler of claim 1 existing between the plurality of battery modules or between the case and the battery module. The battery module according to claim 13, 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, the battery cell being housed in the module case, And the thermally conductive portion of the module case is a thermally conductive resin layer having a thermal conductivity of 1.5 W / mK or more, or a thermally conductive battery pack in thermal contact with the thermally conductive pad. 15. The battery pack according to claim 14, wherein the battery pack includes a thermally conductive portion having a thermal conductivity of 10 W / mk or more, and 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 gap filler .

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