JP6189024B2 - Battery and battery manufacturing method - Google Patents

Description

  Embodiments described herein relate generally to a battery and a method for manufacturing the battery.

  In the method of manufacturing a battery using a laminate film as an exterior member, first, an electrode group including a positive electrode, a negative electrode, and a separator and an electrolyte solution are housed in the exterior member, and one end of the positive electrode lead and the negative electrode lead is drawn out of the exterior member. The exterior member is sealed in a state. Then, a process of charging / discharging and inspecting voltage and resistance by applying a terminal to the positive electrode lead and the negative electrode lead is usually performed.

  A metal adhesive film is welded to the positive electrode lead and negative electrode lead where the laminate film is thermally welded. If the adhesion between the metal adhesive film and the lead is low, liquid leakage or gas permeation may occur. Adhesiveness between the adhesive film and the leads is important for battery reliability. In order to improve this adhesion, some positive electrode leads or negative electrode leads have an insulating coating applied to the surface. Leads having an insulating coating have a lead and charge / discharge terminal There is a problem that the electrical contact with the tester terminal is not sufficient, and accurate charge / discharge and test may not be possible.

Japanese Patent No. 4696457

  The problem to be solved by the present invention is to provide a battery and a battery manufacturing method capable of reliably inspecting charging / discharging and voltage / resistance without contact failure during charging / discharging or voltage / resistance inspection of the battery. And

According to the embodiment, a method for manufacturing a battery including an electrode group including a positive electrode and a negative electrode, an exterior member, a positive electrode lead, and a negative electrode lead is provided. The exterior member has a sealant on the inner surface, and the electrode group is sealed inside by heat welding using the sealant. The positive electrode lead is electrically connected to the positive electrode, and the leading end is drawn out of the exterior member. The negative electrode lead is electrically connected to the negative electrode, and the leading end is drawn out of the exterior member. At least one of the positive electrode lead and the negative electrode lead contains aluminum, and both surfaces are thermally welded to the sealant of the exterior member via the metal adhesive film. In addition, at least one of the positive electrode lead and the negative electrode lead has an insulating coating containing alumina on a surface in contact with the metal adhesive film and a tip surface . The thickness of the insulating coating on the surface in contact with the metal adhesive film is thicker than that of the tip surface of at least one of the leads. The tip surface of at least one of the leads is inclined with respect to either one of the both surfaces of the lead. The thickness of the insulating coating on the front end face is 1 nm or less (not including 0 nm). Charging / discharging or inspection after battery assembly is performed by bringing a terminal into electrical contact with the tip surface of at least one lead.

In addition, according to the embodiment, a battery including an electrode group including a positive electrode and a negative electrode, an exterior member, a positive electrode lead, and a negative electrode lead is provided. The exterior member has a sealant on the inner surface, and the electrode group is sealed inside by heat welding using the sealant. The positive electrode lead is electrically connected to the positive electrode, and the leading end is drawn out of the exterior member. The negative electrode lead is electrically connected to the negative electrode, and the leading end is drawn out of the exterior member. At least one of the positive electrode lead and the negative electrode lead contains aluminum, and both surfaces are thermally welded to the sealant of the exterior member via the metal adhesive film. In addition, at least one of the positive electrode lead and the negative electrode lead has an insulating coating containing alumina on a surface in contact with the metal adhesive film. Furthermore, at least one of the positive electrode lead and the negative electrode lead has a tip surface on which an insulating film containing alumina having a thickness of 1 nm or less (not including 0 nm) is formed. The tip surface of at least one of the leads is inclined with respect to either one of the both surfaces of the lead.

It is a top view which shows roughly the battery manufactured by the method of 1st Embodiment. It is a partial expansion perspective view which shows the electrode group used for the battery shown in FIG. FIG. 3 is a perspective view schematically showing charge / discharge and inspection steps of the manufacturing method of the first embodiment. (A) is a top view of the lead used for the battery of 2nd Embodiment, (b) is sectional drawing obtained when the lead shown by (a) is cut | disconnected in parallel with a long side. It is sectional drawing of another lead | read | reed used for the battery of 2nd Embodiment. It is a figure which shows the charging / discharging curve of Example 1,2. It is a figure which shows the charging / discharging curve of a comparative example.

  Hereinafter, embodiments will be described with reference to the drawings.

(First embodiment)
The battery manufacturing method of the first embodiment includes an assembly process, a charge / discharge process, and an inspection process. In the assembly process, a battery including an electrode group including a positive electrode and a negative electrode, an electrolytic solution, a positive electrode lead, a negative electrode lead, and an exterior member is assembled. In the charge / discharge process, charge / discharge necessary for initial charge / discharge and capacity confirmation is performed. In the inspection process, voltage and resistance are inspected. First, the assembly process will be described with reference to FIGS.

  The battery shown in FIG. 1 is a nonaqueous electrolyte battery. An electrode group 2 is housed in an exterior member 1 made of a laminate film. As the laminate film, for example, a laminate film in which a metal layer is disposed between a sealant layer and a resin layer can be used. By positioning the sealant layer on the inner surface of the exterior member 1, each side of the exterior member 1 can be sealed by heat welding using the sealant layer. The sides to be sealed are not limited to the three sides as shown in FIG. 1, but may be four sides, for example. 1a of FIG. 1 shows the part sealed by heat welding. The sealant layer is formed from, for example, a thermoplastic resin such as polypropylene (PP) or polyethylene (PE). The metal layer is preferably an aluminum foil or an aluminum alloy foil. The resin layer is used to reinforce the metal layer and can be formed from a polymer such as nylon or polyethylene terephthalate (PET). An example of the structure of the aluminum-containing laminate film is a layer structure of nylon / aluminum / polyethylene (or polypropylene). There may be a polyethylene terephthalate layer outside the nylon layer.

  The strip-shaped positive electrode lead 3 and the negative electrode lead 4 have leading ends drawn out to the outside through a heat welding portion 1 a located on one side (for example, short side) of the exterior member 1. The electrode group 2 is not particularly limited, but, for example, as shown in FIG. 2, a strip-shaped positive electrode 5 and a strip-shaped negative electrode 6 are wound in a flat shape with a separator 7 interposed therebetween. . The positive electrode lead 3 is electrically connected to the positive electrode 5, and the negative electrode lead 4 is electrically connected to the negative electrode 6. An electrolytic solution (not shown) is held in the electrode group 2.

  Each of the positive electrode lead 3 and the negative electrode lead 4 has an insulating film 8 (hereinafter referred to as a first insulating film 8) formed on both surfaces. When the positive electrode lead 3 and the negative electrode lead 4 are formed from aluminum or an aluminum alloy, for example, an alumina film is used for the first insulating film 8. The metal adhesive film 9 is formed on the first insulating coating 8 on both surfaces of the positive electrode lead 3 and the negative electrode lead 4 and is in contact with the sealant layer on the inner surface of the exterior member 1. The positive electrode lead 3 and the negative electrode lead 4 are fixed to one side (for example, short side) of the exterior member 1 by heat welding using the metal adhesive film 9 and the sealant layer. Examples of the metal adhesive film 9 include an acid-modified polyolefin film (acid-modified polypropylene).

  As shown in FIG. 3, metal (aluminum) is exposed on the end faces 3 a and 4 a of the positive electrode lead 3 and the negative electrode lead 4, or an insulating film (hereinafter referred to as a second insulating film) thinner than the first insulating film 8. An insulating film) is formed. The second insulating film is made of the same type as the first insulating film 8, and for example, an alumina film is used. The thickness of the first insulating film 8 is thicker than the thickness of the second insulating film. The thickness of the second insulating film is desirably 1 nm or less (including 0 nm). The thickness of the first insulating film 8 is desirably 500 nm or more. The thicknesses of the first and second insulating coatings can be measured by, for example, a scanning electron microscope (SEM).

  The thicknesses of the positive electrode lead 3 and the negative electrode lead 4 can each be in the range of 0.05 mm or more and 0.5 mm or less. By setting it as this range, the sealing performance of the exterior member 1 can be improved while ensuring the strength necessary for the lead. Further, in order to avoid sagging of the insulating film on the surface due to the cutting when the lead is cut and the metal surface of the cut surface is hidden by the sagging, the thickness of the lead is preferably 0.19 mm or more.

  The positive electrode lead 3 and the negative electrode lead 4 are obtained, for example, by forming the first insulating film 8 on both surfaces of a lead material such as aluminum or an aluminum alloy and then cutting the lead material into a desired shape. A new metal surface on which the first insulating film 8 is not formed is exposed on the cut surface. After that, in many cases, the second insulating film is generated on the cut surface by natural oxidation, but since it is thinner than the first insulating film 8, the cut surface is the tip surface 3 a of the positive electrode lead 3 and the negative electrode lead 4. 4a can be used.

  After battery assembly, initial charge / discharge and then capacity check are performed. In this step, as shown in FIG. 3, a first terminal 10 for voltage measurement and a second terminal 11 for flowing current to the battery are respectively provided on the front end surfaces 3a and 4a of the positive electrode lead 3 and the negative electrode lead 4. (Charge / discharge terminal) is electrically contacted, and charging / discharging is performed by flowing current while measuring voltage. A second insulating film is formed on the front end surfaces 3a and 4a of the positive electrode lead 3 and the negative electrode lead 4, but since it is thinner than the first insulating film 8, the first and second terminals 10, 11 and Thus, the electrical contact becomes good, and charging and discharging can be performed efficiently. Thereby, since a big electric current can be sent through a battery, charging / discharging of a battery with a large battery capacity also becomes easy. Aging may be performed after the initial charge / discharge and before confirming the capacity.

  After checking the capacity, the voltage and resistance are inspected. In the inspection process, as shown in FIG. 3, the first terminal 10 and the second terminal 11 (inspector terminal) are brought into electrical contact with the tip surfaces 3a and 4a of the positive electrode lead 3 and the negative electrode lead 4, respectively. Is done. Since the electrical contact between the tip surfaces 3a and 4a of the positive electrode lead 3 and the negative electrode lead 4 and the first and second terminals 10 and 11 is good, the inspection accuracy can be increased.

  Then, a non-aqueous electrolyte battery is obtained by performing pre-shipment charging as necessary. This pre-shipment charging is also desirably performed by bringing the first and second terminals 10 and 11 into electrical contact with the tip surfaces 3 a and 4 a of the positive electrode lead 3 and the negative electrode lead 4.

  In FIGS. 1 to 3, an insulating film is formed on both the positive electrode and the negative electrode lead. However, when copper is used for the negative electrode lead, the insulating film can be formed only on the positive electrode lead. Further, the shape of the exterior member is not limited to a rectangle, and may be a square or the like. The side from which the positive electrode lead or the negative electrode lead is drawn out is not limited to the short side, and may be a long side. The positive and negative electrode leads are not limited to being drawn from the same side, and the positive electrode lead can be drawn from one side and the negative electrode lead can be drawn from the other side. In this case, the direction in which the positive lead is drawn out may be opposite to the direction in which the negative lead is drawn. Furthermore, the shape of the electrode group is not particularly limited, and for example, a stacked type in which the positive electrode and the negative electrode are alternately stacked with a separator interposed therebetween may be used.

  According to the first embodiment described above, charge / discharge or inspection after battery assembly is performed by bringing a terminal into electrical contact with the distal end surface of at least one of the positive electrode lead and the negative electrode lead. On the tip, an insulating coating of less than (including 0) the thickness of the insulating coating formed on both sides of the lead is formed, so that the electrical contact between the lead and the terminal is good, and charge / discharge and inspection Can be reliably performed. In addition, since the electrical contact with the lead during charging / discharging is good, a large current can be passed, so that charging / discharging of a battery having a large battery capacity is facilitated.

(Second Embodiment)
In the battery according to the second embodiment, as a lead of at least one of a positive electrode lead and a negative electrode lead, both surfaces are thermally welded to a sealant of an exterior member via a metal adhesive film, and an insulating coating is formed on a surface in contact with the metal adhesive film And having an inclined surface on which an insulating film having a thickness equal to or less than the thickness of the insulating film (including 0) is formed.

  The battery according to the second embodiment has the same configuration as the battery shown in FIGS. 1 to 2 except that the positive and negative electrode leads 3 and 4 have inclined surfaces. As shown in FIGS. 4 (a) and 4 (b), the positive and negative leads 3 and 4 have the first insulating film 8 formed on both surfaces, and the tip surfaces 3a and 4a are inclined. The inclined front end surfaces 3a and 4a are obtained by cutting the front ends of the positive and negative electrode leads 3 and 4 obliquely. For this reason, a metal (aluminum) is exposed on the tip surfaces 3a and 4a of the positive electrode lead 3 and the negative electrode lead 4, or a second insulating film thinner than the first insulating film 8 is formed by natural oxidation. ing. The inclination angle is not particularly limited, and can be set to any angle except 90 degrees.

  Further, the tip surfaces 3a and 4a of the positive electrode lead 3 and the negative electrode lead 4 do not need to be inclined as a whole. For example, as illustrated in FIG. 5, a part is vertical and the other is inclined. It can also be shaped.

  4 to 5, the insulating coating is formed on both the positive electrode and the negative electrode lead. However, when copper is used for the negative electrode lead, the insulating coating can be formed only on the positive electrode lead.

  According to the second embodiment, at least one of the positive electrode lead and the negative electrode lead has an inclined surface having an insulating film equal to or less than the thickness of the insulating film covering the surface in contact with the metal adhesive film (including 0). Is used. The electrical connection between the lead and the terminal is improved by bringing the terminal for charging / discharging or inspecting device into electrical contact with this inclined surface, so that the electrical connection between the lead and the terminal is good. Is possible. Moreover, by setting it as an inclined surface, the area of the metal part of the part which is not covered with the 1st insulating film becomes large, and it becomes easy to press the terminal for charging / discharging or a test device with respect to a lead surface. Furthermore, since the area of electrical contact with the lead increases during charging and discharging, and a large current can flow, charging and discharging of a battery having a large battery capacity is facilitated.

  Hereinafter, the positive electrode, the negative electrode, the separator, and the electrolytic solution that can be used in the first to second embodiments will be described.

  The positive electrode is produced, for example, by applying a slurry containing a positive electrode active material to a current collector made of an aluminum foil or an aluminum alloy foil. Although it does not specifically limit as a positive electrode active material, The oxide, sulfide, polymer, etc. which can occlude / release lithium can be used. Preferable active materials include lithium manganese composite oxide, lithium nickel composite oxide, lithium cobalt composite oxide, lithium iron phosphate, and the like that can obtain a high positive electrode potential. The negative electrode is produced by applying a slurry containing a negative electrode active material to a current collector made of an aluminum foil or an aluminum alloy foil. The negative electrode active material is not particularly limited, and metal oxides, metal sulfides, metal nitrides, alloys, and the like that can occlude and release lithium can be used. Preferably, the lithium ion occlusion and release potential is metal lithium. It is a substance that becomes noble 0.4V or more with respect to the potential. Since the negative electrode active material having such a lithium ion storage / release potential can suppress the alloy reaction between aluminum or an aluminum alloy and lithium, it is possible to use aluminum or an aluminum alloy for a negative electrode current collector and a negative electrode related component. And For example, there are titanium oxide, lithium titanium oxide, tungsten oxide, amorphous tin oxide, tin silicon oxide, silicon oxide, etc. Among them, lithium titanium composite oxide is preferable. As the separator, a microporous film, a woven fabric, a non-woven fabric, a laminate of the same material or different materials among these can be used. Examples of the material for forming the separator include polyethylene, polypropylene, ethylene-propylene copolymer, ethylene-butene copolymer, and cellulose.

As the electrolytic solution, a nonaqueous electrolytic solution prepared by dissolving an electrolyte (for example, lithium salt) in a nonaqueous solvent is used. Examples of the non-aqueous solvent include ethylene carbonate (EC), propylene carbonate (PC), butylene carbonate (BC), dimethyl carbonate (DMC), diethyl carbonate (DEC), ethyl methyl carbonate (EMC), γ-butyrolactone (γ -BL), sulfolane, acetonitrile, 1,2-dimethoxyethane, 1,3-dimethoxypropane, dimethyl ether, tetrahydrofuran (THF), 2-methyltetrahydrofuran and the like. Nonaqueous solvents may be used alone or in combination of two or more. Examples of the electrolyte include lithium perchlorate (LiClO ₄ ), lithium hexafluorophosphate (LiPF ₆ ), lithium tetrafluoroborate (LiBF ₄ ), lithium arsenic hexafluoride (LiAsF ₆ ), and trifluorometa. A lithium salt such as lithium sulfonate (LiCF ₃ SO ₃ ) can be given. The electrolyte may be used alone or in combination of two or more. The amount of electrolyte dissolved in the non-aqueous solvent is desirably 0.2 mol / L to 3 mol / L.

  In the embodiment, the type of the battery is a non-aqueous electrolyte battery. However, the present invention is not limited to this, and can be applied to an alkaline battery or the like. The number of electrode groups can be one or more. In addition, a battery pack including one or a plurality of the batteries of the embodiment and a charge / discharge control circuit can be configured.

  Examples will be described below.

Example 1
A nonaqueous electrolyte battery having the structure shown in FIG. 1 was produced by the method described below.

<Production process of positive electrode>
As a positive electrode active material, 90% by weight of lithium cobalt oxide (LiCoO ₂ ) powder, 3% by weight of acetylene black, 3% by weight of graphite, and 4% by weight of polyvinylidene fluoride (PVdF) are added to N-methylpyrrolidone (NMP). Mix to prepare a slurry. This slurry was applied to both surfaces of a current collector made of an aluminum foil having a thickness of 12 μm, dried, and then subjected to a pressing process to produce a positive electrode 5.

<Negative electrode fabrication process>
95% by weight of lithium titanium oxide (Li ₄ Ti ₅ O ₁₂ ) powder having a spinel structure as a negative electrode active material, 2.5% by weight of acetylene black as a conductive agent, and 2.5% by weight of polyvinylidene fluoride (PVdF) % Was added to the N-methylpyrrolidone (NMP) solution and mixed to prepare a slurry. This slurry was applied to both sides of a current collector made of an aluminum foil having a thickness of 12 μm, dried, and a negative electrode was produced through a pressing process.

<Production process of electrode group>
The positive electrode 5 and the negative electrode 6 are wound in a flat spiral shape with a separator 7 made of a polyethylene porous film having a thickness of 20 μm interposed therebetween, and then subjected to pressure forming, whereby the electrode shown in FIG. Group 2 was obtained.

<Lead joining process>
As the positive electrode lead 3 and the negative electrode lead 4, pure aluminum (purity: 99.90%) having a thickness of 0.4 mm and a width of 20 mm partially covered with a metal adhesive film (acid-modified polypropylene film) 9 in a reel shape After being prepared and vertically cut at a length of 40 mm, each was joined to the positive electrode and the negative electrode by ultrasonic welding.

  In addition, as a result of SEM observation of the cross section of the aluminum of the positive electrode lead 3 and the negative electrode lead 4, the first insulating coating 8 (alumina film) having a thickness of 0.5 μm was present on the surface, and the tip surfaces 3a, 4a It was confirmed that a second insulating film (alumina film) having a thickness of 1 nm was present.

<Nonaqueous electrolyte preparation process>
Non-aqueous electrolyte by dissolving lithium hexafluorophosphate (LiPF ₆ ) at a concentration of 1.0 mol / L in a mixed solvent of ethylene carbonate (EC) and methyl ethyl carbonate (MEC) (mixing volume ratio 1: 2). Was prepared.

<Sealing process>
The electrode group was housed in an exterior member made of a laminate film having a layer structure of nylon / aluminum / unstretched polypropylene and having a thickness of 0.11 mm, and the positive electrode lead 3 and the negative electrode lead 4 were exposed from the exterior member 1 by 20 mm. A metal adhesive film 9 was interposed between both surfaces of the positive electrode lead 3 and the negative electrode lead 4 and the inner surface of the exterior member 1. Among each side of the exterior member, heat sealing was performed on one side where the positive and negative electrode leads 3 and 4 extended and one side where the positive electrode lead 3 and the negative electrode lead 4 did not extend. Next, a non-aqueous electrolyte was injected from the remaining side that was not heat-sealed, and the electrode group was impregnated with the non-aqueous electrolyte. Subsequently, the exterior side member was sealed by joining the remaining one side by heat sealing, and the nonaqueous electrolyte secondary battery of the structure shown in FIG. 1 was obtained.

<Charging / discharging process>
While measuring the voltage between the positive electrode lead 3 and the negative electrode lead 4 after injecting and sealing the electrolyte, the current was passed between the positive electrode lead 3 and the negative electrode lead 4 to perform initial charging, and then the discharge capacity was measured. A nonaqueous electrolyte battery was obtained. At that time, in order to measure charging / discharging by the four-terminal method, a voltage terminal (first terminal) 10 and a current terminal (second terminal) perpendicular to the tip surfaces 3a and 4a of the positive electrode lead 3 and the negative electrode lead 4 respectively. 11 was pressed by a spring to ensure electrical contact.

  The lower limit specification of the discharge capacity is 1.505 Ah, and the number of defective discharge capacities when 100 similar batteries were produced was tabulated. The results are shown in Table 1 below.

(Example 2)
Except that the front end surfaces 3a and 4a of the positive electrode lead 3 and the negative electrode lead 4 have an oblique cross section with a length of 0.8 mm, they were produced in the same manner as in Example 1, and the number of defective discharge capacities was tabulated.

(Comparative example)
In the charge / discharge process, the charge / discharge voltage terminal (first terminal) 10 and the current terminal (second terminal) 11 are pushed perpendicularly to the surface of the first insulating film 8 on the surface of the positive electrode lead 3 and the negative electrode lead 4. The number of defective discharge capacities was tabulated in the same manner as in Example 1 except that it was applied.

(Number of defective discharge capacity)
Table 1 shows the number of defective discharge capacities when 100 batteries were produced for Examples 1 and 2 and Comparative Example.

  As shown in Table 1, in the comparative example, discharge capacity failure occurred, and some of them were not charged. In Example 1 and Example 2, no defective discharge capacity occurred. Since all the electrode groups are manufactured in the same manner, the defect in the comparative example is considered to be due to the contact failure between the positive electrode lead 3 and the negative electrode lead 4 and the charge / discharge current terminal 11 and voltage terminal 10.

  Moreover, the charging / discharging curve of Example 1, 2 is shown in FIG. 6, and the charging / discharging curve of a comparative example is shown in FIG. As shown in FIG. 7, the (time-voltage) curve or the (time-current) curve during charging / discharging of the battery that has reached the capacity specification of the comparative example is such that the voltage or current suddenly increases or decreases in the middle. Continuous behavior is seen. On the other hand, as shown in FIG. 6, the charge / discharge curves of Example 1 and Example 2 were continuous and exhibited normal behavior.

  According to the battery manufacturing method of at least one embodiment and example described above, the end face of at least one of the positive electrode lead and the negative electrode lead has a thickness equal to or less than the thickness of the insulating coating formed on both surfaces of the lead (including 0). ) Is formed, the electrical contact between the lead and the terminal is improved, and charging / discharging and inspection can be reliably performed.

Although several embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.
Hereinafter, the invention described in the scope of claims of the present application will be appended.
[1]
An electrode group including a positive electrode and a negative electrode;
An exterior member having a sealant on the inner surface and in which the electrode group is sealed by heat welding using the sealant;
A positive electrode lead electrically connected to the positive electrode and having a leading end drawn out of the exterior member;
A battery manufacturing method including a negative electrode lead electrically connected to the negative electrode and having a tip portion drawn out of the exterior member,
At least one of the positive electrode lead and the negative electrode lead has both surfaces thermally bonded to the sealant of the exterior member via a metal adhesive film, and an insulating film is formed on the surface in contact with the metal adhesive film, The insulating coating is thicker than the tip of the at least one lead,
A method of manufacturing a battery, wherein charging / discharging or inspection after battery assembly is performed by bringing a terminal into electrical contact with the tip surface of the at least one lead.
[2]
The battery manufacturing method according to [1], wherein the at least one lead contains aluminum, and the insulating coating contains alumina.
[3]
The battery according to [2], wherein the at least one lead is obtained by cutting a lead material having an insulating film formed on both sides, and the cut surface is used as the tip surface of the at least one lead. Manufacturing method.
[4]
[2] The method for producing a battery according to [2], wherein the thickness of the insulating coating on the tip surface is 1 nm or less (including 0 nm).
[5]
An electrode group including a positive electrode and a negative electrode;
An exterior member having a sealant on the inner surface and in which the electrode group is sealed by heat welding using the sealant;
A positive electrode lead electrically connected to the positive electrode and having a leading end drawn out of the exterior member;
A battery including a negative electrode lead electrically connected to the negative electrode and having a leading end drawn out of the exterior member;
At least one of the positive electrode lead and the negative electrode lead has both surfaces thermally bonded to the sealant of the exterior member via a metal adhesive film, and an insulating film is formed on the surface in contact with the metal adhesive film, And a battery having an inclined surface on which an insulating film having a thickness equal to or smaller than the thickness of the insulating film (including 0) is formed.
[6]
The battery according to [5], wherein the thickness of the at least one lead is 0.19 mm or more.
[7]
The battery according to any one of [5] or [6], wherein the thickness of the insulating coating on the inclined surface is 1 nm or less (including 0 nm).

  DESCRIPTION OF SYMBOLS 1 ... Exterior member, 1a ... Welding part, 2 ... Electrode group, 3 ... Positive electrode lead, 4 ... Negative electrode lead, 3a, 4a ... Front end surface, 5 ... Positive electrode, 6 ... Negative electrode, 7 ... Separator, 8 ... First insulation Coating: 9 ... Metal adhesive film, 10 ... Voltage terminal, 11 ... Current terminal.

Claims (4)

An electrode group including a positive electrode and a negative electrode;
An exterior member having a sealant on the inner surface and in which the electrode group is sealed by heat welding using the sealant;
A positive electrode lead electrically connected to the positive electrode and having a leading end drawn out of the exterior member;
A battery manufacturing method including a negative electrode lead electrically connected to the negative electrode and having a tip portion drawn out of the exterior member,
At least one of the positive electrode lead and the negative electrode lead contains aluminum, both surfaces of which are thermally welded to the sealant of the exterior member via a metal adhesive film, and a surface and a tip in contact with the metal adhesive film An insulating coating containing alumina is formed on the surface, and the thickness of the insulating coating on the surface in contact with the metal adhesive film is thicker than that of the tip surface of the at least one lead, and the tip surface is formed on both surfaces. It is inclined with respect to either one
The thickness of the insulating coating on the tip surface is 1 nm or less (excluding 0 nm),
The discharge or inspection after battery assembly, wherein at least one of the manufacturing method of the terminal on the distal end surface by electrical contact line power selling battery leads. Wherein at least one of the lead is obtained by cutting the lead material insulating film formed on both surfaces, manufacturing method of battery of claim 1, Ru with a cutting plane as the front end surface of the at least one lead . An electrode group including a positive electrode and a negative electrode;
An exterior member having a sealant on the inner surface and in which the electrode group is sealed by heat welding using the sealant;
A positive electrode lead electrically connected to the positive electrode and having a leading end drawn out of the exterior member;
A battery including a negative electrode lead electrically connected to the negative electrode and having a leading end drawn out of the exterior member;
At least one of the positive electrode lead and the negative electrode lead contains aluminum, both surfaces of which are thermally welded to the sealant of the exterior member via a metal adhesive film, and alumina on the surface in contact with the metal adhesive film And a tip surface on which an insulating coating containing alumina having a thickness of 1 nm or less (not including 0 nm) is formed. , batteries you are inclined either for one of the two sides. The battery according to claim 3 wherein the thickness of at least one lead is Ru der than 0.19 mm.

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