JP2003132865A - Non-aqueous electrolyte secondary battery and equipment built in with the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a non-aqueous electrolyte secondary battery and equipment built in with the same, in which a laminated sheet that can be cheaply and easily fixed to the battery use equipment at good accuracy is used as the outer package. SOLUTION: An opening and/or a slit are provided for fixing the laminated sheet to the battery use equipment at two locations in a side or at least one location in two sides selected from four sides of the circumference of the laminated sheet. The equipment has protrusions provided for fixing at positions corresponding to the opening and/or slit.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a non-aqueous electrolyte secondary battery and a device incorporating the same, and more particularly to a method for fixing a non-aqueous electrolyte secondary battery and a device using a laminate sheet as an outer case.

[0002]

2. Description of the Related Art In recent years, the performance of mobile electronic devices such as mobile phones and personal digital assistants largely depends not only on the performance of semiconductor elements and electronic circuits, but also on the performance of rechargeable secondary batteries. It is demanded that the secondary battery to be mounted be increased in capacity, be lightweight and thin at the same time, and be inexpensive. As a secondary battery that meets these demands, a nickel-hydrogen storage battery having an energy density about twice that of a nickel-cadmium storage battery has been developed, and then a lithium secondary battery using a non-aqueous electrolyte has a higher energy density. It was developed as and is in the spotlight.

The non-aqueous electrolyte secondary battery has a cylindrical shape, a prismatic shape, and a flat shape, and in particular, a non-aqueous electrolyte in which a battery element is housed in an outer case formed of a laminate sheet mainly composed of a resin film. Secondary batteries have great expectations as batteries that can be made thin, and their development is urgent.

[0004]

However, in order to mount a battery having such a laminated sheet as an outer case on a device using a battery, the battery having the laminated sheet as an outer case is built in a resin case, It was fixed by fitting the battery-using device to the connector and connection terminal, which was a factor of cost increase.

It is a main object of the present invention to provide a method for fixing a non-aqueous electrolyte secondary battery and a device, which is inexpensive, easy and accurate, and which uses a laminate sheet as an outer case.

[0006]

DISCLOSURE OF THE INVENTION The present invention for solving the above-mentioned problems comprises a flat battery element comprising a positive electrode plate in the form of a sheet or a film, a separator holding an electrolyte and a negative electrode plate, and a resin film as a main component. In the battery to be stored in the outer case formed by the laminated sheet of
The laminate sheet is a non-aqueous electrolyte secondary battery, characterized in that an opening and / or a groove for fixing with a device using a battery is provided, wherein the opening and the groove are:
It is preferable that the laminate sheet is provided at two locations on at least one side selected from four sides without battery elements or at one location on at least two sides.

Further, the apparatus is characterized in that the projections for fixing the openings and / or the grooves provided on the laminate sheet are provided in this way.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

1A and 1B are a plan view and a sectional view of a non-aqueous electrolyte secondary battery, respectively.

In FIG. 1B, the non-aqueous electrolyte secondary battery has a positive electrode active material layer 4 formed by applying a paste containing a positive electrode active material and a binder to an aluminum current collector, followed by drying and pressing. To make.

Next, the negative electrode current collector 7 made of copper is coated with a paste containing a negative electrode active material and a binder, dried, and pressed to form the negative electrode active material layer 6. A polymer paste dissolved in a solvent is used for film formation and drying to prepare a separator 5 that absorbs and holds a non-aqueous electrolyte.

The positive electrode plate and the negative electrode plate thus produced are laminated with a separator interposed therebetween, and the positive electrode lead 11 is welded to the lead mounting portion 12 disposed in the positive electrode current collecting portion, to thereby collect the negative electrode current collecting portion. After the negative electrode lead 13 is welded to the lead mounting portion 14 arranged in, the metal foil is placed between the polyolefin resin films and the whole is laminated and integrated into a bag-shaped case 1 made of a laminated sheet, and the The non-aqueous electrolyte secondary battery 8 is produced by injecting the electrolytic solution, sealing it with the welded seal portion 2 of the bag-shaped case, aging it to gelate the non-aqueous electrolytic solution, and charging and discharging it.

The positive electrode current collector 3 is made of aluminum foil or aluminum foil that has been lathed or etched, and preferably has a thickness of 10 μm to 60 μm. Also,
The negative electrode current collector 7 is composed of a copper foil and a copper foil subjected to lath processing or etching processing, and has a thickness of 10 μm to 50 μm.
Is preferred.

The positive electrode active material layer 4 comprises a positive electrode active material and a binder,
If necessary, a conductive material and a plasticizer are added, and a paste prepared by kneading and dispersing in a solvent is applied on a PET film, dried, and pressed to prepare.

The negative electrode active material layer 6 includes a negative electrode active material and a binder,
If necessary, a conductive material and a plasticizer are added, and a paste prepared by kneading and dispersing in a solvent is applied onto the negative electrode current collector 7, dried, and pressed to prepare.

A lithium-containing transition metal compound capable of accepting lithium ions as a guest is used as the positive electrode active material. For example, cobalt, manganese, nickel,
LiCoO ₂ , a composite metal oxide of at least one metal selected from chromium, iron and vanadium and lithium, LiCoO ₂ ,
LiMoO ₂ , LiNiO ₂ , LiCo _x Ni _(1-x) O
₂ (0 <x <1) LiCrO ₂ , αLiFeO ₂ , LiV
O _{2 and the} like are preferable.

Examples of the negative electrode active material include graphite, activated carbon, and those obtained by firing and carbonizing phenol resin, pitch, etc. In particular, from the viewpoint of safety and cycle life characteristics, the lattice spacing of the lattice planes (002) is (D ₀₀₂ ) is 3.35
A carbon material having a graphite type crystal structure of 0 to 3.400Å is preferable.

Examples of the binder include a fluororesin material which maintains the adhesion between the active materials, a polymer material having a polyalkylene oxide skeleton, and a styrene-butadiene copolymer. As the fluorine-based resin material, polyvinylidene fluoride (PVDF), a copolymer P (VDF-) of vinylidene fluoride (VDF) and hexafluoropropylene (HFP).
HFP) is preferred.

As a conductive material and a conductive additive to be added as required, carbonaceous conductive materials such as acetylene black, graphite and carbon fiber are preferable, and as a plasticizer, diisobutyl phthalate, diethyl phthalate, di-n phthalate are preferable. -Phthalate esters such as butyl, dipropyl phthalate, dihexyl phthalate are preferred.

As the solvent, a solvent capable of dissolving the binder is suitable. In the case of an organic binder, an organic solvent such as acetone, cyclohexanone, N-methyl-2-pyrrolidone (NMP), methyl ethyl ketone (MEK), etc. A single solvent or a mixed solvent obtained by mixing these is preferable, and water is preferable in the case of an aqueous binder.

The same polymer as the binder can be used for the separator 5, and the polymer paste dissolved in the solvent is formed on a heat resistant film such as polyethylene terephthalate (PET) resin and dried. It can be produced or used by adhering a fluororesin material similar to the binder to both sides of a microporous membrane made of a polyolefin resin such as polyethylene resin or polypropylene resin. The negative electrode and the negative electrode are laminated by applying temperature and pressure to produce an electrode plate group. The temperature at this time is preferably pressed at a pressure of 0.2 MPa to 5.0 MPa while being heated from 40 ° C. to a temperature not higher than the softening point of the binder in the electrode plate group.

The laminated bag-shaped case 1 is a laminated sheet in which a metal foil is placed between polyolefin resin films and the whole is laminated and integrated. An adhesive layer, a metal foil, and an insulating layer are attached from the inside in contact with the laminated electrode plates. The layers are sequentially stacked. The adhesive layer is preferably an acid-modified polyolefin resin having excellent adhesiveness to leads, the metal layer is preferably an aluminum metal foil having excellent gas barrier properties and light shielding properties, and the insulating layer is preferably a polyamide resin having excellent mechanical strength.

The non-aqueous electrolytic solution comprises a non-aqueous solvent and an electrolyte, and the non-aqueous solvent contains a cyclic carbonate and a chain carbonate as main components. As the cyclic carbonate, ethylene carbonate (EC),
At least one selected from propylene carbonate (PC) and butylene carbonate (BC) is preferable. The chain carbonate is preferably at least one selected from dimethyl carbonate (DMC), diethyl carbonate (DEC), ethyl methyl carbonate (EMC) and the like.

As the electrolyte, for example, a lithium salt having a strong electron-withdrawing property is used. For example, LiPF ₆ or LiB is used.
F ₄ , LiClO ₄ , LiAsF ₆ , LiCF ₃ SO ₃ , L
iN (SO ₂ CF ₃ ) ₂ , LiN (SO ₂ C ₂ F ₅ ) ₂ , Li
C (SO ₂ CF _{3) 3} and the like. These electrolytes may be used alone or in combination of two or more. These electrolytes are preferably dissolved in the non-aqueous solvent at a concentration of 0.5 to 1.5M.

The welded seal portion 2 of the bag-shaped case 1 is sealed by heat welding.

For aging, the polymer is preferably gelled by aging at a temperature of 45 ° C. to 90 ° C. for 0.5 hours to 3 hours.

To charge and discharge, the battery capacity should be 95% at room temperature.
It is preferable to charge the battery to an electric capacity of 100% to 105%.

The laminate sheet of the non-aqueous electrolyte secondary battery thus prepared is provided at two locations on at least one side selected from four sides of the periphery 15 having no battery element or at one location on at least two sides. The non-aqueous electrolyte secondary battery can be easily assembled by fitting the fixing opening portion and / or groove portion 16 with the battery-using device and the positioning and fixing protrusion 23 provided in the battery-using device. The equipment provided can be made.

A hole for fixing the battery-using device and / or
Alternatively, as the shape of the groove portion 16, (a) circle in FIG.
(B) + character notch, (c) -character notch, (d) 2 holes A, (e) 2 holes B, (f) square, (g) rectangle,
(H) Examples thereof include crescent moons, which can be freely combined and used. The position is as shown in FIG.
(A) Two locations on opposite two sides, one location on the diagonal of (a) two sides of FIG. 2, (b) two locations on one side, (c) one location on four corners, (d) It is possible to name one at the same position on two opposite sides.

Further, in order to fix the fixing opening and / or the groove 16, the protrusion 23 provided in the battery-using device shown in FIG. , (B) a cylinder with a tip protrusion, (c) a spiral,
(D) many protrusions, (e) triangular prism, (f) deformed cylinder,
Examples thereof include (g) key-like protrusions, (h) tip end taper, and (i) quadrangular prism, which can be used in combination freely.

[0031]

EXAMPLES The present invention will be described in detail with reference to Examples and Comparative Examples, but these do not limit the present invention in any way.

Example 1 A positive electrode plate was prepared by using LiCoO ₂ as a positive electrode active material, acetylene black as a conductive material, vinylidene fluoride / hexafluoropropylene copolymer P (VDF-HFP) as a binder, and a plasticizer. A positive electrode paste prepared by kneading and dispersing phthalic acid-n-dibutyl (DBP) in N-methyl-2-pyrrolidone (NMP) which is a solvent was applied onto an aluminum current collector 3 having a thickness of 50 μm and subjected to lath processing. After drying, the positive electrode plate having the positive electrode active material layer 4 was manufactured by pressing.

The negative electrode plate comprises spherical graphite as a negative electrode active material, vapor-grown carbon fiber as a conduction aid, and P (VDD) as a binder.
F-HFP), a negative electrode paste obtained by kneading and dispersing phthalate-n-dibutyl (DBP) as a plasticizer in acetone as a solvent, a current collector obtained by lathing a copper foil having a thickness of 50 μm and an aperture ratio of 50%. After coating and drying on both surfaces of No. 7, the negative electrode plate having the negative electrode active material layer 6 was produced by pressing.

As the separator 5, a solution prepared by dissolving P (VDF-HFP) in a mixed solvent of acetone and cyclohexanone as a solvent is polyethylene phthalate (PE).
T) It was formed by forming a film on a resin film, drying it at a temperature of 80 ° C., and removing the mixed solvent.

The positive electrode plate and the negative electrode plate thus produced are laminated with the separator 5 in between, and the positive electrode lead 11 is welded to the lead mounting portion 12 arranged in the positive electrode current collecting portion to form the negative electrode current collecting portion. After welding the negative electrode lead 13 to the lead attachment portion 14 arranged in, the laminated electrode plate group was prepared by thermocompression bonding at a temperature of 130 ° C. under a pressure condition of 0.4 MPa for 1.5 seconds. 20 at the temperature of 60 ℃
The plasticizer DBP was removed by immersing in a xylene solution for a minute.

Next, an electrode plate group was placed in a laminated bag-like case 1 composed of an acid-modified polypropylene resin layer having a thickness of 30 μm, an aluminum foil layer having a thickness of 50 μm, and a polyamide resin layer having a thickness of 20 μm from the inside. Stowed.

Then, after injecting a non-aqueous electrolyte solution in which LiPF ₆ was dissolved at a concentration of 1.0 M into a mixed solvent in which ethylene carbonate (EC) and ethyl methyl carbonate (EMC) were mixed at a ratio of 2: 1, 0.3M at a temperature of 230 ° C
Although thermocompression bonding was performed for 2.0 seconds under a pressure condition of Pa and sealing was performed with the welded seal portion 2, the temperature rise with respect to the positive electrode plate and the negative electrode plate was in a negligible range.

After aging at a temperature of 60 ° C. for 3 hours to gel the polymer and the separator in the positive electrode plate and the negative electrode plate and to retain the non-aqueous electrolyte, the battery capacity was kept at 10 ° C. at room temperature.
%, The battery is charged to 100% of the battery capacity, and then discharged to a voltage of 3.0V at a current value of 20% of the battery capacity, with an average value of n = 5 and a vertical dimension of 35.2 m.
A non-aqueous electrolyte secondary battery 8 having m, a lateral dimension of 61.8 mm, and a thickness of 3.32 mm was produced.

The thus prepared non-aqueous electrolyte secondary battery laminate sheet shown in FIG. 1 (a) is provided with two holes on each of two sides out of the four sides, which are fixing holes 16 for fixing to battery-using equipment.
As shown in FIG. 3 (a), a circular hole having a diameter of 4.0 mm is provided, and the battery of the battery using device 21 including the constituent member 24 of the battery using device shown in FIG. By fitting the protrusion 23 disposed at the disposition position 22 with a 3.8 mm diameter column having a tapered tip portion (distal end diameter 3.2 mm) shown in FIG. It was possible to fabricate a device containing a non-aqueous electrolyte secondary battery.

Example 2 A positive electrode plate was prepared by using LiCoO ₂ as a positive electrode active material, acetylene black as a conductive material, and vinylidene fluoride / hexafluoropropylene copolymer P (VDF-HFP) as a binder. A positive electrode paste kneaded and dispersed in N-methyl-2-pyrrolidone (NMP) was applied onto an aluminum foil current collector 3 having a thickness of 15 μm and dried, and then pressed to form a positive electrode active material layer 4 A positive electrode plate having the positive electrode lead 11 was produced.

The negative electrode plate was composed of spherical graphite as a negative electrode active material, vapor grown carbon fiber as a conduction aid, and P (VDD) as a binder.
F-HFP), a negative electrode paste kneaded and dispersed in acetone as a solvent is applied to both surfaces of a current collector 7 obtained by lathing a copper foil having a thickness of 12 μm and dried, and then pressed to form a negative electrode active material. A negative electrode plate having the layer 6 and the negative electrode lead 13 was produced.

The separator 5 is a microporous film made of polypropylene resin having a thickness of 15 μm and having a P thickness of 2.5 μm on both sides.
After the positive electrode plate and the negative electrode plate are spirally wound with the separator 5 made of a layer made of (VDF-HFP) interposed therebetween,
An oval electrode plate group was produced by thermocompression bonding for 1.5 seconds at a temperature of 130 ° C. and a pressure of 0.4 MPa.

Next, an electrode plate group was placed inside a laminated bag-like case 1 consisting of an acid-modified polypropylene resin layer having a thickness of 30 μm, an aluminum foil layer having a thickness of 50 μm, and a polyamide resin layer having a thickness of 20 μm from the inside. Stowed.

Then, after pouring a non-aqueous electrolyte solution in which LiPF ₆ was dissolved at a concentration of 1.0 M into a mixed solvent in which ethylene carbonate (EC) and ethyl methyl carbonate (EMC) were mixed at a ratio of 2: 1, 0.3M at a temperature of 230 ° C
Although thermocompression bonding was performed for 2.0 seconds under a pressure condition of Pa and sealing was performed with the welded seal portion 2, the temperature rise with respect to the positive electrode plate and the negative electrode plate was in a negligible range.

Aging at a temperature of 90 ° C. for 30 minutes,
After polymerizing the polymer in the positive electrode plate and the negative electrode plate and the polymer layer provided on the surface of the separator and holding the non-aqueous electrolyte, the same procedure as in Example 1 was performed at a current value of 10% of the battery capacity at room temperature. After being charged to 100% of the battery capacity and then discharged to a voltage of 3.0 V at a current value of 20% of the battery capacity, the average value of n = 5, the vertical dimension is 35.2 mm, and the horizontal dimension is 61. A non-aqueous electrolyte secondary battery 8 having a thickness of 8 mm and a thickness of 3.32 mm was produced.

2A of the laminated sheet of the non-aqueous electrolyte secondary battery shown in FIG. 2A, which is produced as described above, is provided with an opening 16 for fixing to a battery-using device, one on each of two sides of the four sides.
As shown in FIG. 3 (b), a + -shaped notch having a diameter of 3.5 mm is provided, and a protrusion 23 that can be fixed and arranged in a battery-using device corresponding to the notch is shown in FIG. 4 (d).
3.2m diameter with many 0.1mm high protrusions
By fitting the m column, it was possible to fabricate a device inexpensively, easily and accurately with a built-in non-aqueous electrolyte secondary battery.

[0047]

As described above, according to the present invention, by arranging the opening and / or groove for fixing with the device using the battery on the periphery of the resin film-based laminate sheet where there is no battery element. Thus, it is possible to provide a device that is inexpensive, easily and accurately equipped with a non-aqueous electrolyte secondary battery.

[Brief description of drawings]

FIG. 1A is a plan view according to an embodiment of the present invention. (B) A sectional view according to an embodiment of the present invention

FIG. 2 (a) to (d) are views showing an example showing the positions of fixing apertures and / or grooves of the present invention.

3 (a) to 3 (h) are views showing an example showing the shape of a fixing opening portion and / or groove portion of the present invention.

4 (a) to (i) are views showing an example showing the shape of a protrusion of the present invention.

FIG. 5 is a schematic plan view showing the positions of the batteries in the battery-using device of the present invention.

[Explanation of symbols]

1 Exterior case 2 Sealing part 3 Positive electrode current collector 4 Positive electrode active material layer 5 separator 6 Negative electrode active material layer 7 Negative electrode current collector 8 Non-aqueous electrolyte secondary battery 11 Positive electrode lead 12 Positive electrode current collector 13 Negative electrode lead 14 Negative electrode current collector 15 Surrounding the outer case 16 Fixing openings and / or grooves 21 Battery-powered equipment 22 Battery location 23 Projection 24 Components of battery-powered equipment

Continued front page    (72) Inventor Takeshi Fukumasa             1006 Kadoma, Kadoma-shi, Osaka Matsushita Electric             Sangyo Co., Ltd. F-term (reference) 5H011 AA06 CC02 CC06 CC10 DD07                       DD13 KK01                 5H040 AA01 AA06 AS12 AT04 AY02                       AY14 CC14 CC35 CC37 CC38                       JJ02 JJ03 LL10 NN03

Claims (3)

[Claims] 1. A battery in which a flat battery element comprising a sheet-shaped or film-shaped positive electrode plate, a separator holding an electrolyte, and a negative electrode plate is housed in an outer case formed of a laminate sheet mainly composed of a resin film,
The non-aqueous electrolyte secondary battery, wherein the laminate sheet is provided with an opening and / or a groove for fixing to a device using a battery. 2. The opening and / or groove is provided at two locations on at least one side selected from four sides around the laminate sheet where there is no battery element, or one location on at least two sides. The non-aqueous electrolyte secondary battery according to claim 1. 3. The non-aqueous electrolyte secondary battery according to claim 1 or 2, and a protrusion for fixing an opening and / or a groove provided in this battery. Equipment characterized by.