JP6131087B2 - Battery liquid composition for tab lead sealing and battery manufacturing method - Google Patents

Description

  The present invention relates to a liquid composition for encapsulating a tab lead, which bonds an outer packaging material of a battery and a tab lead, and a method for producing the battery.

  In recent years, the fields of information-related equipment and communication equipment have been developed, and the spread of small portable electronic equipment such as notebook computers, digital cameras, video cameras, and mobile phones has been promoted. As power sources and batteries for electric vehicles used in these equipment Secondary batteries using a non-aqueous electrolyte such as a lithium ion secondary battery having a high energy density are widely used.

  For exterior materials such as batteries using non-aqueous electrolytes, for example, a polyamide film with mechanical strength is laminated on one side of a metal foil such as an aluminum foil, and the other side is a thermoplastic resin such as polypropylene or polyethylene. The exterior material which has the structure where the heat seal film which consists of was laminated | stacked is used.

  The battery case is overlapped so that the heat seal films made of thermoplastic resin are in contact with each other using the exterior material as described above, heat-sealing the peripheral edge, and one end is An open bag-like case is formed. In this battery case, battery components such as positive electrode, negative electrode, electrolyte, and tab lead are housed, the tab lead is extended to the outside of the case, and the opening of the exterior material is sealed with the extended tab lead sandwiched between them. A laminate-type battery pack or battery is formed.

  In consideration of harsh conditions such as high or low temperature outdoor environments using small portable electronic devices and electric vehicles, electrolytes such as non-aqueous electrolyte inside the battery pack will not leak, and external water or air etc. Is required to have a high adhesiveness between the exterior material and the sealing portion of the tab lead.

In order to improve the adhesiveness and airtightness of the sealing portion of the exterior material and the tab lead, a method using a tab lead provided with a plurality of holes has been proposed (Patent Document 1).
Moreover, in order to raise airtightness, the method of arrange | positioning a heat seal film to a tab lead and heat-seal | fusing with the heat seal film of an exterior material is proposed (patent document 2).

JP 2003-86153 A JP 2009-26581 A

  Even when the above-mentioned exterior material is used, the connection between the exterior material and the tab lead has been conventionally performed by the following method in which bubbles and gaps remain in the adhesive layer, and electrolysis such as a non-aqueous electrolyte solution has occurred. Liquid leakage may occur. FIG. 1 is a conceptual diagram in which an exterior material and a tab lead are bonded by a conventional method, FIG. 1 (a) is a side view showing the exterior material and the tab lead before heat-sealing, and FIG. It is a side view which shows the exterior material and tab lead after heat sealing | fusion.

  As shown in FIG. 1A, an exterior material 4 in which a heat seal film 1 composed of a thermoplastic resin and an outer surface side film 3 are laminated on a metal foil 2 is a heat seal of two exterior materials 4 and 4. The tab leads 6a and 6b are arranged around the heat seal film 8 made of thermoplastic resin so as to be sandwiched between the heat seal films 1 and 1. Two exterior members 4 sandwiching 6b are pressed to heat the heat seal film 1 of each exterior member 4 and the heat seal film 8 disposed around the tab lead 6 to provide two exterior members. In a state where the tab lead 6 is sandwiched between the materials 4 and 4, they are bonded and sealed.

  As shown in FIG. 1A, in a state where the heat seal films 1 and 1 of the two exterior materials 4 and 4 and the heat seal film 8 disposed around the tab lead 6 are sandwiched, the two exterior materials 4 , 4 is difficult to completely seal, and a gap 9 remains. When the heat seal films 1 and 1 of the outer packaging materials 4 and 4 and the heat seal films 8 and 8 disposed around the tab leads 6a and 6b are heat-sealed and bonded together, as shown in FIG. When the melted product of the sealing films 1 and 8 spreads, the gap (see the gap 9 in FIG. 1A) can be filled and sealed. However, the gap is not completely filled, and the bubbles 10 and the gap are not filled. In some cases, the adhesive layer 7 is formed. Such bubbles 10 and gaps in the adhesive layer 7 may cause leakage of an electrolyte solution such as a non-aqueous electrolyte solution inside the battery or intrusion of external water or air into the battery. In some cases, air bubbles may exist in the heat seal film 8 arranged around the tab lead 6, and this is one of the factors for forming the adhesive layer 7 including the air bubbles 10.

  In recent years, there has been a demand for higher capacity and higher output of batteries. For relatively large batteries that satisfy these requirements, there is a tendency to increase the thickness of tab leads. When used, bubbles and gaps are more likely to occur.

  The present invention provides a liquid composition for encapsulating a tab lead and a method for producing the battery, which can be bonded with higher airtightness without causing bubbles or gaps between the battery exterior material and the sealed portion of the tab lead. Let it be an issue.

The present invention relates to a liquid composition for sealing a tab lead of a battery, comprising a thermosetting compound, a latent curing agent, and a thermoplastic filler.
The present invention 2 relates to a liquid composition for sealing a tab lead of a battery, including a thermosetting compound, a latent curing agent, a thermoplastic filler, and an inorganic filler.
This invention 3 is related with the liquid composition for tab lead sealing of this invention 1 or 2 containing 10-90 mass parts of thermoplastic fillers with respect to 100 mass parts of thermosetting compounds.

The present invention 4 includes a step of applying a liquid composition for sealing a tab lead containing a thermosetting resin, a latent curing agent and a thermoplastic filler to a heat seal film of an exterior material in which a metal foil and a heat seal film are laminated. The tab lead is disposed in the liquid composition for sealing the tab lead applied to the heat seal film of the exterior material, the liquid composition for sealing the tab lead and the tab lead are sandwiched between the two exterior materials, and the exterior material and the tab lead are heat bonded. The manufacturing method of the battery which includes the structural member of a battery including a process.
The present invention 5 relates to the battery manufacturing method of the present invention 4, wherein two exterior materials are heated while being pressurized in the step of heat bonding the exterior material and the tab lead.

  The present invention uses a liquid composition for sealing a tab lead to bond the tab lead and the exterior material, thereby suppressing the generation of bubbles and gaps that are likely to occur at the end of the tab lead, etc. Can be bonded with higher airtightness.

(A) It is a side view which shows the state before heat-sealing (a) two exterior materials and the tab lead (for positive electrodes and negative electrodes) sandwiched between the two exterior materials, b) It is a side view which shows the state after heat sealing | fusion. It is process drawing which shows one Embodiment of the manufacturing method of the battery of this invention. They are the top view (a) and sectional drawing (b) which show the image of a battery structure. The test body 15 which adhere | attached the exterior material and the exterior material is shown, (a) Front view, (b) Side view, (c) Top view. The test body 16 which adhere | attached the exterior material and the tab lead is shown, (a) Front view, (b) Side view, (c) Top view.

Hereinafter, preferred embodiments of the present invention will be described.
The present invention relates to a liquid composition for sealing a tab lead of a battery, comprising a thermosetting compound, a latent curing agent, and a thermoplastic filler.

  As the thermosetting compound, it is preferable to use an epoxy compound or an oxetane compound, a (meth) acrylate compound, and a partially (meth) acrylated epoxy compound. These compounds may be used alone or in combination of two or more.

  When the thermosetting compound is an epoxy compound, the epoxy compound is preferably a liquid epoxy resin. This liquid epoxy resin includes, for example, a bisphenol A type epoxy compound, a bisphenol F type epoxy compound, a novolac type epoxy compound, a polycyclic aromatic epoxy compound, a modified epoxy compound thereof, and an alicyclic epoxy compound having a weight average molecular weight of 4 million or less. Etc., one kind of liquid compound may be used alone, or two or more kinds may be used in combination. Further, these epoxy compounds may be used by dissolving a solid or highly viscous epoxy compound at room temperature. Examples of the solid epoxy compound include HP-4700, EXA-4710, and HP-4770 (manufactured by DIC). Examples of the highly viscous epoxy compound include an epoxy compound having a viscosity of 10,000 mPa · s or more. Examples of the highly viscous epoxy compound include HP-4032D, N740, N660, and HP-7200 (manufactured by DIC).

  When the thermosetting compound is an oxetane compound, examples of the oxetane compound include 3-ethyl-3-hydroxymethyloxetane (OXA) and 1,4-bis [{(3-ethyl-3-oxetanyl) methoxy} methyl] benzene. (XDO), 3-ethyl-3- (phenoxymethyl) oxetane (OXT-211 (POX)), 2-ethylhexyloxetane (OXT-212 (EHOX)), xylylene bisoxetane (OXT-121 (XDO)), Bis (3-ethyl-3-oxetanylmethyl) ether (OXT-221 (DOX)), 3-ethyl-[{(3-triethoxysilylpropoxy) methyl) oxetane, oxetanylsilsesquioxane, phenol novolac oxetane, etc. Can be mentioned. The number in parentheses indicates the product number of Toagosei Co., Ltd. Each oxetane compound may be used individually by 1 type, or may be used in combination of 2 or more type.

When the thermosetting compound is an epoxy compound, the latent curing agent may be an anion curing type curing agent such as polyamine or imidazole, an onium salt type cationic curing type curing agent such as sulfonium salt or iodonium salt, or ethylenediamine or diethylenetriamine. It is preferable to use amine curing type curing agents such as triethylenetetramine and 3,3′-diethyl-4,4′aminodiphenylmethane. When the thermosetting compound is an epoxy compound and the latent curing agent is an anion curing type curing agent, the blending amount of the latent curing agent is 1 to 20 parts by mass with respect to 100 parts by mass of the thermosetting compound. Preferably it is 3-15 mass parts. These latent curing agents may be used alone or in combination of two or more.
When the latent curing agent is a cationic curing type curing agent, the blending amount of the latent curing agent is 0.1 to 15 parts by mass, more preferably 0.5 to 10 parts by mass with respect to 100 parts by mass of the thermosetting compound. Part. These latent curing agents may be used alone or in combination of two or more.
When the latent curing agent is an amine curing type curing agent, the blending amount of the latent curing agent is 1 to 150 parts by mass, more preferably 5 to 100 parts by mass with respect to 100 parts by mass of the thermosetting compound. These latent curing agents may be used alone or in combination of two or more. By blending the latent curing agent in the above range with the thermosetting compound, it is possible to form an adhesive layer that favorably bonds the exterior material and the tab lead.

  When the thermosetting compound is a (meth) acrylate compound, the (meth) acrylate compound is preferably a liquid (meth) acrylate compound, for example, methyl (meth) acrylate or ethyl having a weight average molecular weight of 2 million or less. It is preferable to use (meth) acrylate, t-butyl (meth) acrylate, isobutyl (meth) acrylate, or the like. These (meth) acrylate compounds may be used individually by 1 type, and may use 2 or more types together. Further, these (meth) acrylate compounds may be used by dissolving a solid or highly viscous (meth) acrylate compound at room temperature. In this specification, room temperature means 20 ° C. ± 5 ° C. Examples of the highly viscous (meth) acrylate compound include a (meth) acrylate compound having a viscosity of 10,000 mPa · s or more. Examples of the highly viscous (meth) acrylate compound include UN7700, R280, UA-1 (manufactured by Light Chemical Co., Ltd.) and the like.

  When the thermosetting compound is a partially (meth) acrylated epoxy compound, the partially (meth) acrylated epoxy compound is preferably a liquid partially (meth) acrylated epoxy compound, such as a bisphenol A type epoxy compound. And a partial (meth) acrylated epoxy compound which is a reaction product of (meth) acrylic acid. In this compound, bisphenol A type epoxy compound and (meth) acrylic acid are reacted with 0.9 to 1.1 equivalents of carboxylic acid groups with respect to 2 equivalents of epoxy groups in the presence of a basic catalyst according to a conventional method. Can be obtained. Next, about 4 times by weight of toluene and the same amount of pure water were added to the reaction product, stirred at 60 to 80 ° C. for 1 hour, and allowed to stand to separate into an organic layer and an aqueous layer. The aqueous layer is removed. This operation is repeated 3 to 5 times. Finally, the organic layer is recovered, and the remaining toluene is removed by vacuum distillation to purify the partially (meth) acrylated epoxy compound that has been subjected to the reduction treatment of the water-soluble ionic substance. Specific examples of the above-mentioned bisphenol A type epoxy compound include, for example, jER828, 834 [manufactured by Mitsubishi Chemical Corporation], Epicron 850 [manufactured by DIC Corporation], and the like. Among these raw material compounds, compounds obtained by reducing the water-soluble ionic substance are preferable, and for example, Epicron 850S (manufactured by DIC) is preferable. These partial (meth) acrylated epoxy compounds may be used alone or in combination of two or more. Further, these partial (meth) acrylated epoxy compounds may be used by dissolving a solid or highly viscous partial (meth) acrylated epoxy compound at room temperature. Examples of the highly viscous partial (meth) acrylate compound include partial (meth) acrylate compounds having a viscosity of 10,000 mPa · s or more. Examples of the highly viscous partial (meth) acrylate compound include compounds derived from jER1001, 1004 (manufactured by Mitsubishi Chemical Corporation), Epicron 860, 4055 (manufactured by DIC Corporation), and the like.

  When the thermosetting compound is a (meth) acrylate compound, examples of the latent curing agent include diacyl peroxides such as isobutyl peroxide and 2,4-dichlorobenzoyl peroxide; di-n-propyl peroxydicarbonate, Peroxydicarbonates such as diisopropylperoxydicarbonate; peroxyesters such as cumylperoxyneodecanoate and 1,1,3,3-tetramethylbutylperoxyneodecanoate; α, α′-bis ( It is preferable to use organic peroxides such as dialkyl peroxides such as t-butylperoxy) diisopropylbenzene and dicumyl peroxide; hydroperoxides such as diisopropylbenzene hydroperoxide and cumene hydroperoxide. When the thermosetting compound is a (meth) acrylate compound, the blending amount of the latent curing agent with respect to 100 parts by mass of the thermosetting compound may be within a range where good adhesiveness can be obtained, and preferably 0. 0.1 to 20 parts by mass, more preferably 0.5 to 10 parts by mass. By blending the latent curing agent in the above range with the thermosetting compound, it is possible to form an adhesive layer that favorably bonds the exterior material and the tab lead.

  Thermoplastic fillers include polyolefins such as polyethylene or polypropylene, alicyclic saturated hydrocarbon resins, polystyrene, styrene butadiene rubber (SBR), polyamide, polyester, polyurethane, poly (meth) acrylate polymer, polyvinyl chloride (PVC), It is preferable to use a powdery material containing a thermoplastic resin such as polyvinyl acetate, polyepoxide, polyacetal, acrylonitrile-butadiene-styrene copolymer (ABS) or a copolymer thereof, polyphenylene oxide, polyvinylidene chloride, or a mixture of these polymers. These thermoplastic fillers may be used alone or in combination of two or more.

  The thermoplastic filler is preferably 10 to 90 parts by weight, more preferably 15 to 80 parts by weight, still more preferably 20 to 75 parts by weight, and particularly preferably 20 to 60 parts by weight with respect to 100 parts by weight of the thermosetting compound. It is. When the amount of the thermoplastic filler in the liquid composition for sealing the tab lead is within the above range, the tab lead is used before the heat seal film and the tab lead of the exterior material are heat-bonded using the exterior material including the heat seal film. It is possible to fill the gaps in the tab lead sealing portion with the sealing liquid composition. When heat-sealing the heat-seal film of the exterior material and the tab lead, the liquid composition for sealing the tab lead and the melted heat-seal film are mixed or mixed to form an adhesive layer, and the gap is filled in advance. The tab lead and the exterior material can be bonded without causing bubbles or gaps at the end of the tab lead.

The liquid composition for sealing a tab lead of a battery includes a thermosetting compound, a latent curing agent, a thermoplastic filler, and an inorganic filler.
Examples of the inorganic filler include metal oxides such as silica, alumina, bomalite, zirconia, and titanium oxide, hydroxides such as aluminum hydroxide, magnesium hydroxide, and calcium hydroxide, and composite oxides. Among them, the inorganic filler is preferably talc having a particle diameter D50 by laser diffraction of 0.5 to 50 μm. By including the inorganic filler, there are advantages such as reduction of moisture permeability, improvement of hydrofluoric acid resistance, and imparting flame retardancy. When the inorganic filler is included, the inorganic filler is preferably 10 to 90 parts by mass, more preferably 20 to 60 parts by mass with respect to 100 parts by mass of the thermosetting compound.

  Next, a battery manufacturing method will be described.

  The present invention is a step of applying a tablead sealing liquid composition containing a thermosetting compound, a latent curing agent and a thermoplastic filler to a heat seal film of an exterior material in which a metal foil and a heat seal film are laminated, A step of placing a tab lead in a liquid composition for sealing a tab lead applied to a heat seal film of an exterior material, sandwiching the liquid composition for sealing the tab lead and the tab lead between two exterior materials, and heat-bonding the exterior material and the tab lead A method for producing a battery including battery constituent members. The tab lead sealing liquid composition used in the production method of the present invention may further contain an inorganic filler.

FIG. 2 is a process diagram showing one embodiment of a method for producing a battery of the present invention.
As shown in FIG. 2 (a), first, a thermosetting compound, a latent curing agent and heat are applied to the heat sealing film 1 of the exterior material 4 in which the metal foil 2, the heat sealing film 1, and the outer surface film 3 are laminated. A liquid composition 5 for sealing a tab lead containing a plastic filler is applied. Although it does not specifically limit as a coating method, It can apply | coat using apparatuses, such as a gravure coater, a die coater, a roll coater, a blade coater, a dispenser, a jet dispenser, a screen printer. The tab lead sealing liquid composition 5 may further contain an inorganic filler.

  Next, as shown in FIG. 2B, tab leads (positive electrode tab lead 6a, negative electrode tab lead 6b) are arranged in the tab lead sealing liquid composition 5 applied to the heat seal film 1 of the exterior material 4. To do.

  Next, as shown in FIG. 2C, the tab lead sealing liquid composition 5 and the tab lead (the positive electrode tab lead 6a, the negative electrode tab lead) are coated with another exterior material 4 in which the metal foil 2 and the heat seal film 1 are laminated. 6b) is sandwiched.

  Finally, as shown in FIG. 2 (d), the tab lead sealing liquid composition 5 and the tab leads (positive electrode tab lead 6a, negative electrode tab lead 6b) are combined with the heat seal film 1 of one outer packaging material 4 and the other outer packaging. It is sandwiched between the heat seal films 1 of the material 4 and heat-bonded. The heat-seal films 1 and 1 are melted by heating, and the melted heat-seal film and the liquid composition 5 for sealing the tab lead are mixed or mixed together to form the adhesive layer 7 without causing bubbles or gaps. The material 4 and the tab lead 6 can be bonded. The heating temperature is not particularly limited as long as it is a temperature at which the liquid composition for sealing the tab lead and the heat seal film melt, but is preferably 100 to 200 ° C, more preferably 140 to 180 ° C. The heating time is not particularly limited, but is preferably 0.1 to 30 minutes, more preferably 5 to 20 minutes.

  The tab lead is not particularly limited as long as it is used for a general battery. For example, the specifications of tab leads that are usually used in laminated lithium ion secondary batteries vary depending on the size of the battery. For large batteries, the conductor width is 15.0 to 100 mm, and the conductor thickness is 0.1 to A tab lead of about 0.8 mm is used. For medium-sized batteries, tab leads having a conductor width of about 8.0 to 15.0 mm and a conductor thickness of about 0.1 to 0.5 mm are used. For small batteries, tab leads having a conductor width of 1.5 to 10 mm and a conductor thickness of about 0.08 to 0.2 mm are used. Moreover, the material which comprises a tab lead also changes with each for positive electrodes or negative electrodes. The liquid composition for sealing the tab lead of the battery of the present invention can bond the tab lead and the exterior material without being affected by the thickness or material of the tab lead, without causing bubbles or gaps at the end of the tab lead. it can. Moreover, the liquid composition for sealing a tab lead of the battery of the present invention can also be applied to a tab lead having a heat seal film disposed around it. The tab lead in which the heat seal film is arranged around and the liquid composition for sealing the tab lead is a heat seal film arranged around the melted tab lead when the heat seal film is heat-bonded to the heat seal film of the exterior material, and the melted exterior Mixed with or compatible with the heat seal film of the material, to form an adhesive layer, and without causing bubbles or gaps at the end of the tab lead in which the gap is previously filled with the liquid composition for sealing the tab lead, The exterior material can be bonded.

  FIG. 3 is a top view (a) showing an image of an actual battery structure in which two battery exterior materials and a tab lead are bonded to each other and battery components such as a positive electrode 14a, a negative electrode 14b, a separator 12 and an electrolytic solution 13 are included. It is sectional drawing (b). As shown in FIG. 3, according to the present invention, the adhesive layer 7 including the tab lead sealing liquid composition 5 and the melted heat seal film 1 includes the tab lead 6, the exterior material 4, the exterior material 4, and the exterior material. 4 can be bonded with higher airtightness.

  In the process of heat bonding by sandwiching the tab lead between the heat seal film of one exterior material and the heat seal film of the other exterior material, the one exterior material, the tab lead, and the other exterior material are outside of both exterior materials. It is preferable to pressurize and heat bond. By heat-bonding, the exterior material and the tab lead can be bonded with higher airtightness by the melted heat seal film and the melted liquid composition for sealing the tab lead.

  EXAMPLES Next, specific embodiments of the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.

(Examples 1-3)
Using the thermosetting compound, the latent curing agent and the thermoplastic filler shown in Table 1, the compositions shown in Table 1 were mixed to obtain compositions of Examples 1 to 3 and Comparative Examples 1 and 2. The numerical values shown in Table 1 represent parts by mass.

(Manufacturing method of the test body in which the exterior material and the exterior material are bonded)
As the exterior material 4, an exterior material 4 in which an outer surface side film 3, an aluminum foil layer 2, and a heat seal film 1 made of polypropylene (PP) are laminated in this order was used. The exterior material 4 was cut into a width of 3 cm and a length of 6 cm to prepare a test piece. Two spacers 11 and 11 having a width of 0.5 cm and a thickness of 220 μm were arranged at both ends of the outer packaging materials 4 and 4 of the two test pieces. The composition 5 of Examples 1-3 and Comparative Examples 1-2 was apply | coated to the magnitude | size of 3 cm in length and 2 cm in width by the dispensing method between the two spacers, respectively. The composition 5 and the two spacers 11 are sandwiched between the heat sealing films 1 and 1 of the two exterior materials 4 and 4, and glass (not shown) is further disposed outside the two exterior materials. The laminated body arranged in the order of the material 4, the composition 5, the spacer 11, the exterior material 4, and the glass was sandwiched between clips and pressed from the outside of the two exterior materials 4 and 4. The laminate was put in a 180 ° C. oven sandwiched between clips and heated for 10 minutes to melt the heat seal film 1 and the composition 5 of the exterior material 4 to bond the exterior material 4 and the exterior material 4. The test body 15 was produced. 4A and 4B show a test body 15 in which an exterior material and an exterior material are bonded to each other, and are (a) a front view, (b) a side view, and (c) a top view.

(Manufacturing method of test body with exterior material and tab lead bonded)
As the exterior material 4, an exterior material 4 in which an outer surface side film 3, an aluminum foil layer 2, and a heat seal film 1 made of polypropylene (PP) are laminated in this order was used. The exterior material 4 was cut into a width of 3 cm and a length of 6 cm to prepare a test piece. Two spacers 11 and 11 having a width of 0.5 cm and a thickness of 220 μm were arranged on both ends of the outer packaging material 4 of one test piece and the tab lead 6 cut to a width of 3 cm and a length of 6 cm. The composition 5 of Examples 1-3 and Comparative Examples 1-2 was apply | coated to the magnitude | size of 3 cm in length and 2 cm in width by the dispensing method between the two spacers, respectively. The composition 5 and the two spacers 11 are sandwiched between the heat seal film 1 of one exterior material 4 and one tab lead 6, and glass (not shown) is disposed outside the exterior material 4 and the tab lead 6, A laminated body arranged in the order of glass, exterior material 4, composition 5, spacer 11, tab lead 6, and glass was sandwiched between clips, and pressurized from outside the exterior material 4 and tab lead 6. The laminate was put in an oven at 180 ° C. sandwiched between clips and heated for 10 minutes to melt the heat seal film 1 and the composition 5 of the exterior material 4 and to bond the exterior material 4 and the tab lead 6. A body 16 was produced. FIGS. 5A and 5B show a test body 16 in which an exterior material and a tab lead are bonded, and FIG. 5A is a front view, FIG. 5B is a side view, and FIG.

(Adhesion test)
One exterior material of each specimen was fixed, and the other exterior material was pulled manually in the 180 ° direction, and the tensile strength was observed. The case where the exterior material was not peeled off even when pulled strongly was rated as ◯, and the case where the exterior material was easily peeled off was marked as x. The results are shown in Table 1.

  As shown in Table 1, the test pieces using the liquid compositions for sealing the tab leads of Examples 1 to 3 did not peel off the exterior material even when pulled strongly, and did not cause bubbles or gaps. It was confirmed that the material was hermetically bonded. On the other hand, the test piece of Comparative Example 1 using the composition containing only the inorganic filler and the test piece of Comparative Example 2 using the composition not containing the filler were bonded without generating bubbles or gaps. It was confirmed that the materials easily peeled off and did not have sufficient adhesive strength as a battery. In addition, as shown in Table 1, the test pieces using the tab lead sealing liquid compositions of Examples 1 to 3 did not peel off the outer packaging material and the tab lead even when pulled strongly, without causing bubbles or gaps. It was confirmed that the material and the tab lead were hermetically bonded. On the other hand, the test piece of Comparative Example 1 using the composition containing only the inorganic filler and the test piece of Comparative Example 2 using the composition not containing the filler were bonded without generating bubbles or gaps. It was confirmed that the material and the tab lead easily peeled off and did not have sufficient adhesive strength as a battery.

  According to the present invention, it is possible to hermetically bond an exterior material enclosing a battery component and a tab lead connectable to an external terminal, even when used under severe conditions such as an outdoor environment. Therefore, it is possible to produce a battery having safety and durability, which is industrially useful.

DESCRIPTION OF SYMBOLS 1 Heat seal film 2 Metal foil 3 Outer surface side film 4 Exterior material 5 Tab lead sealing liquid composition 6 Tab lead 6a Positive electrode tab lead 6b Negative electrode tab lead 7 Adhesive layer 8 Heat seal film 9 Crevice 10 Air bubble 11 Spacer 12 Separator 13 Electrolyte 14a positive electrode 14b negative electrode 15 specimen (exterior material and external material)
16 Specimen (exterior material and tab lead)

Claims (6)

A liquid composition for sealing a tab lead of a battery, comprising a thermosetting compound, a latent curing agent, and a thermoplastic filler (excluding a rubbery core-shell polymer) . A liquid composition for sealing a tab lead of a battery, comprising a thermosetting compound, a latent curing agent, a thermoplastic filler (excluding a rubbery core-shell polymer) and an inorganic filler.   The liquid composition for sealing a tab lead according to claim 1 or 2, comprising 10 to 90 parts by mass of a thermoplastic filler with respect to 100 parts by mass of the thermosetting compound. The thermoplastic filler is a polyolefin, alicyclic saturated hydrocarbon resin, polyamide, polyester, polyurethane, poly (meth) acrylate polymer, polyvinyl chloride (PVC), polyvinyl acetate, polyepoxide, polyacetal, copolymers thereof, polystyrene, The battery tab lead according to any one of claims 1 to 3, wherein the battery tab lead is a powder containing at least one selected from the group consisting of polyphenylene oxide, polyvinylidene chloride, and a mixture of these polymers. Liquid composition for sealing . A liquid composition for encapsulating a tab lead, comprising a thermosetting resin, a latent curing agent and a thermoplastic filler (excluding a rubbery core-shell polymer) in a heat sealing film of an exterior material in which a metal foil and a heat sealing film are laminated. A tab lead is disposed in the tab lead sealing liquid composition applied to the heat seal film of the exterior material, the tab lead sealing liquid composition and the tab lead are sandwiched between the two exterior materials, and the exterior material The manufacturing method of the battery which includes the structural member of a battery including the process of heat-bonding a tab lead. The battery manufacturing method according to claim 5 , wherein in the step of heat bonding the exterior material and the tab lead, the two exterior materials are heated while being pressed.