JP2003288942A - Stacked lithium battery - Google Patents

Abstract

(57) Abstract: A positive electrode end face electrode (5) electrically connected to the positive electrode (2) in a laminate 25 in which at least one set of a positive electrode (2), an electrolyte (4), and a negative electrode (3) are laminated; The power generating element 1 having the negative electrode end face electrode 6 electrically connected to the negative electrode 3 is connected to the positive electrode terminal 14 and the negative electrode terminal 15 on the base plate 11 of the exterior body 13 via a conductive adhesive, respectively. At the time of joining, the conductive adhesive prevents a short circuit caused by wrapping around the opposing surface 25a of the power generating element 1 facing the base plate 11, and prevents a battery function from being impaired due to an impact such as a drop. A power generating element has a surface facing a base plate.
a, the insulating layer 16 is adhered to the base plate 11 and is fixed to the base plate 11 via the adhesive layer 17.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a compact and energy-saving structure in which a power generation element in which one or more sets of a positive electrode, an electrolyte or a separator containing an electrolyte, and a negative electrode are laminated and integrated is enclosed in an outer casing. The present invention relates to a laminated lithium battery having high density and excellent heat resistance and moisture resistance.

[0002]

2. Description of the Related Art Conventionally, the problems to be solved by the invention
A rechargeable coin-type battery such as a lithium secondary battery has been put into practical use and is used as a main power source for various electronic devices and a power source for memory backup. In particular, for memory backup of small portable electronic devices, an ultra-small coin-type battery having a diameter of 6 mm or less has become mainstream.

However, since the coin type battery has a structure in which the upper surface thereof is a positive electrode terminal and the lower surface thereof is a negative electrode terminal, a separate terminal is required when mounting on a circuit board, and as a result, the battery itself is Since a mounting area and a height larger than the size are required, the size cannot be reduced, and the number of parts is increased, which leads to an increase in cost.

Therefore, as a small battery that can be directly mounted on a circuit board without using terminals or the like, one or more sets of a positive electrode, an electrolyte or a separator containing an electrolyte, and a negative electrode are stacked. It is composed of an integrated laminated body, and a positive electrode end face electrode made of a metal film is attached to one end face of the laminated body to electrically connect to the positive electrode electrode exposed at one end face of the laminated body, and the laminated body is laminated. There is proposed a laminated battery in which a negative electrode end surface electrode made of a metal film is attached to the other end surface of the body and electrically connected to the negative electrode electrode exposed at the other end surface of the laminated body (JP-A-6- 231896).

According to this laminated battery, both the positive electrode terminal and the negative electrode terminal are provided on the lower surface of the laminated body,
Since it can be directly joined to the wiring on the circuit board by soldering, the mounting area is limited to the area of the battery, and since it is not necessary to use a separate terminal for mounting, it is possible to reduce the number of parts and the cost. There was an advantage that it could be suppressed.

However, since the laminated battery disclosed in Japanese Patent Laid-Open No. 6-231896 has a structure in which the laminated body is exposed to the outside, it cannot be said that it is a realistic structure for a lithium battery that does not like water, and the electrolyte is However, there is a problem that the electrolytic solution cannot be used.

[0007] Japanese Patent Laid-Open No. 6-231896 also proposes to cover the laminated body forming the laminated battery with an exterior body, but since the laminated body is not completely enclosed in the exterior body. , I can not solve the above problems,
Further, there is a problem that a separate terminal is required when mounting on a circuit board, the mounting area becomes large, and the number of parts cannot be reduced.

Further, in recent years, in order to reduce the size of parts and improve the efficiency of mounting work, it is strongly demanded for batteries to be compatible with automatic soldering using the solder reflow method as with other electronic parts. However, there is a problem that a battery in which the laminated body is not completely covered by the outer casing as in JP-A-6-231896 cannot be mounted together with other electronic components by using the solder reflow method.

Therefore, the applicant of the present invention has proposed, as a laminated lithium battery for solving these problems, a positive electrode, an electrolyte or a separator containing an electrolyte, a negative electrode for a negative electrode on a base plate having a positive electrode terminal and a negative electrode terminal. A power generation element having a positive electrode end face electrode electrically connected to the positive electrode electrode and a negative electrode end face electrode electrically connected to the negative electrode is placed in a laminated body in which one or more electrodes are laminated. , Electrically connecting the positive electrode end surface electrode of the power generating element and the positive electrode terminal of the base plate, and electrically connecting the negative electrode end surface electrode of the power generating element and the negative electrode terminal of the base plate, The one in which a lid is joined to the base plate to hermetically house the power generating element has been previously proposed (Japanese Patent Application No. 2001-2001).
-331349).

According to this laminated lithium battery, since the laminated body is hermetically housed in the outer body composed of the base plate and the lid body, the electrolytic solution can be used as the electrolyte and the lithium battery is not sensitive to water. You can also configure
Further, there is an advantage that it is possible to simultaneously mount with other electronic components using the solder reflow method.

By the way, in the laminated lithium battery previously proposed by the applicant of the present invention, a method for electrically connecting each end surface electrode of the power generating element and the terminal on the base plate is to use a conductive adhesive. At this time, the conductive adhesive flows out to the surface facing the base plate of the laminate forming the power generating element, and if, for example, the negative electrode is on the surface facing the base plate of the laminate, the positive electrode When the conductive adhesive connecting the end surface electrode and the positive electrode terminal reaches the negative electrode forming the surface facing the base plate of the laminated body, a short circuit occurs, which causes a problem that the battery does not function as a battery.

Further, since the end face electrodes of the power generating element and the terminals of the base plate are joined by the minimum conductive adhesive required for connection, a shock is applied to the power generating element and the position of the power generating element is displaced. When this occurs, there is also a problem that the connection portion is disconnected and the battery does not function as a battery.

[0013]

In view of the above problems, the present invention provides a positive electrode, an electrolyte or a separator containing an electrolyte, and a negative electrode on a base plate having a positive electrode terminal and a negative electrode terminal. A power generation element having a positive electrode end face electrode electrically connected to the positive electrode electrode and a negative electrode end face electrode electrically connected to the negative electrode is disposed in a laminate in which at least one set is stacked, and the power generation is performed. The positive electrode end surface electrode of the element and the positive electrode terminal of the base plate are electrically connected via a conductive adhesive, and the negative electrode end surface electrode of the power generating element and the negative electrode terminal of the base plate are electrically conductive. A laminated lithium battery electrically connected via an adhesive, and a lid member joined to the base plate to hermetically accommodate the power generating element, wherein an insulating layer is provided on a surface of the laminated body facing the base plate. And the above power generation is required The characterized in that are bonded via an adhesive layer on the base plate.

An adhesive tape is used as the insulating layer,
The adhesive layer is at least one kind selected from an epoxy resin adhesive, a silicone resin adhesive, an acrylic resin adhesive, a polyimide resin adhesive, a polyamideimide resin adhesive, and a phenol resin adhesive. It is preferable to use an insulating adhesive.

Further, in the power generating element, the positive electrode and the negative electrode have a rectangular planar shape, and the positive electrode and the negative electrode are laminated so as to intersect each other when viewed from the laminating direction. It is preferable that

[0016]

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

FIG. 1 (a) is a plan view showing an example of the laminated lithium battery of the present invention, and FIG. 1 (b) is AA of FIG. 1 (a).
1B is a sectional view taken along the line BB in FIG.
FIG. 1D is a perspective view showing a laminated state of the power generation element included in the laminated lithium battery of the present invention.

In this laminated lithium battery 21, a positive electrode 2 and a negative electrode 3 each having a rectangular planar shape are placed in an outer casing 13 made of a ceramic base plate 11 and a lid 12. The positive electrode 2 and the negative electrode 3 are arranged so as to intersect with each other so that their long sides are orthogonal to each other.
And at least one set having the electrolyte 4 are laminated to form a laminated body 25, and an insulating layer 16 is provided on the surface of the laminated body 25 facing the base plate 11, and the positive electrode 2 is exposed. The power generation element 1 having the positive electrode end surface electrode 5 on the end surface of the laminated body 25 and the negative electrode end surface electrode 6 on the end surface of the laminated body 25 where the negative electrode 3 is exposed is housed in the power generation element 1. The space formed by the base plate 11 and the lid 12 is hermetically sealed.

Further, at one of the opposite ends of the base plate 11, there are provided positive electrode terminals 14 integrally formed from the upper surface to the end face and the lower surface of the base plate 11, respectively, and at the other opposite end part of the base plate 11. Each have a negative electrode terminal 15 integrally formed from the upper surface to the end surface and the lower surface of the base plate 11, and each positive electrode end surface electrode 5 of the power generation element 1 is electrically connected to each positive electrode terminal 14 of the base plate 11. While connecting via the adhesive layer 10, each negative electrode end face electrode 6 of the power generation element 1 is connected to each negative electrode terminal 15 of the base plate 11 via the conductive adhesive layer 10, and further, the power generation element 1
The insulating layer 16 and the base plate 11 adhered to the adhesive layer 17
It is bonded through.

As described above, the laminated lithium battery 21 of the present invention uses the positive electrode 2 and the negative electrode 3 each having a rectangular planar shape, and these are crossed so that their long sides are orthogonal to each other. Are arranged in such a manner as to collect current from both ends of the positive electrode 2 and both ends of the negative electrode 3, respectively. Therefore, from the terminals 14 and 15 to the power generation section (the intersection of the positive electrode 2 and the negative electrode 3). ), The internal resistance of the laminated lithium battery 21, especially each terminal 1 can be shortened.
The transfer resistance of electrons from the center of the power generation unit (intersection of the positive electrode 2 and the negative electrode 3) to the center of the power generation unit 4 and 15 can be reduced, and the load characteristics can be improved. As a result, the energy density of the laminated lithium battery 21 can be increased, and the size can be further reduced as compared with the conventional laminated battery.

Further, the laminated lithium battery 21 itself can be designed compactly, and each terminal 14,
Since 15 is integrally formed from the upper surface to the lower surface of the base plate 11, when mounting on the circuit board, the mounting area is approximately the size of the laminated lithium battery 21, and therefore the circuit board is small. The mounting density can be increased.

Moreover, since the power generating element 1 is completely sealed in the exterior body 13 composed of the base plate 11 and the lid body 12, it is excellent in airtightness, heat resistance and moisture resistance and has electrical characteristics better than that of the outside air. Deterioration can be prevented for a long period of time.

Further, by forming the laminated lithium battery 21 with a heat-resistant material, the battery 21 that can be mounted on the circuit board by the solder reflow method.
Can be provided.

Further, the laminated lithium battery 21 of the present invention
Shows that the insulating layer 16 is applied to the surface of the laminated body 25 forming the power generation element 1 facing the base plate 11, and the insulating layer 16 and the base plate 11 are adhered to each other via the adhesive layer 17. Characterize.

In this way, by providing the insulating layer 16 on the surface of the laminate 25 facing the base plate 11, the power generating element 1
End electrodes 5, 6 and terminals 14, 1 on the base plate 11
5 is electrically connected via the conductive adhesive 10,
Even if the conductive adhesive 10 begins to flow to the surface of the laminate 25 facing the base plate 11, no short circuit occurs.
It is easy to handle during the manufacturing process and can be manufactured with high yield.

However, the average thickness T of the insulating layer 16 is 210.
When it exceeds μm, the laminated lithium battery 21 becomes too large, and it is difficult to manufacture the insulating layer 16 having an average thickness T of less than 1 μm. Therefore, the average thickness T of the insulating layer 16 is preferably 1 μm to 210 μm. In addition,
The average thickness T of the insulating layer 16 is an average value obtained by measuring the thickness of the insulating layer 16 at arbitrary points.

The region where the insulating layer 16 is formed is not particularly limited as long as it is formed so as to prevent a short circuit. As shown in FIG. 2, the base plate 11 of the laminated body 25 is formed. The insulating layer 1 on the entire surface 25a facing the
6 is preferably formed.

By the way, as a material for forming the insulating layer 16, an adhesive tape, a paint or an adhesive can be used.

Of these, if an adhesive tape is used as the insulating layer 16, it is only necessary to attach the adhesive tape cut out in a predetermined shape to the surface 25a of the laminated body 25 facing the base plate 11. It is preferable because workability can be improved.

On the other hand, when a paint or an adhesive is used as the insulating layer 16, it is necessary to apply it to the surface 25a of the laminated body 25 facing the base plate 11 in advance and then dry or cure it. When it is undried or uncured, when it is attempted to adhere to the base plate 11 at the same time as connecting the respective end surface electrodes 5 and 6 of the power generating element 1 and the terminals 14 and 15, the conductive adhesive 10 causes the insulating adhesive 16 This is because there is a possibility that they may be mixed with the liquid and that a short circuit may occur due to the flow of the insulating layer 16.

When an adhesive tape is used as the insulating layer 16, polyimide, fluororesin, polyphenylene sulfide, polyethylene naphthalate, polyester,
At least one kind of insulating resin film selected from aramid resin may be used, which has a pressure sensitive adhesive composed of a silicone pressure sensitive adhesive or an acrylic pressure sensitive adhesive on the surface.

Furthermore, the laminated lithium battery 21 of the present invention
In this case, the insulating layer 16 of the power generation element 1 and the base plate 11 are fixed to each other via the adhesive layer 17.

As a result, even if the battery 21 is dropped and an impact is applied thereto, for example, the positional deviation of the power generating element 1 in the outer casing 13 does not occur, and therefore the terminals 14, 15 accompanying the positional deviation of the power generating element 1 are generated. It is possible to prevent disconnection from the connection with.

Further, an insulating layer 16 is formed on the surface 25a of the power generating element 1 facing the base plate 11, and the insulating layer 16 and the ceramic base plate 11 are bonded together by an adhesive layer 17.
Since it is fixed by the above, a strong joining force can be obtained. That is, the ceramic has relatively good wettability with the adhesive, and since the surface of the ceramic forming the base plate 11 has many fine pores, the anchor effect due to the adhesive getting into the pores causes the base The joint force between the plate 11 and the adhesive layer 17 can be increased, and at the joint portion with the power generation element 1,
Since the insulating layer 16 that is easily compatible with the adhesive layer 17 is provided, a stronger adhesive force can be obtained as compared with the case of directly adhering to the power generation element 1.

The familiar insulating layer 16 is, for example, an adhesive which swells with a solvent, which swells when it comes into contact with an adhesive containing a solvent and is impregnated with the adhesive to absorb the solvent. When it volatilizes and then cures, it fuses and integrates, showing a strong adhesive force.

Further, as the pattern shape of the adhesive layer 17, the power generation element 1 has the base plate 11 even if an impact is applied.
There is no particular limitation as long as it does not come off more easily. In addition to the elliptical shape shown in FIG. 1 (c), the ring shape shown in FIG. 3 (a), FIG. 3 (b) Adopt a variety of pattern shapes, such as the star shape shown in Fig. 3, the cross shape shown in Fig. 3 (c), and the cross shuriken shape shown in Fig. 3 (d). You can

The adhesive layer 17 is selected from an epoxy resin adhesive, a silicone resin adhesive, an acrylic resin adhesive, a polyimide resin adhesive, a polyamideimide resin adhesive, and a phenol resin adhesive. At least one kind of adhesive may be used.

Since the above-mentioned resin materials are all excellent in heat resistance, it is possible to operate the battery at a high temperature by using a resin material selected from these. Depending on the combination with other battery materials, it is also possible to provide a laminated lithium battery that can support automatic soldering using the solder reflow method.

By the way, the laminated lithium battery 2 of the present invention
As the positive electrode 2 and the negative electrode 3 forming 1
A conductive material, a binder, an organic solvent, a filler and a solid electrolyte as required, and a composite material obtained by drying a slurry prepared and produced, or a sintered body made of the active material can be used.

As the active material, lithium manganese composite oxide, manganese dioxide, lithium nickel composite oxide,
Although lithium cobalt composite oxide, lithium nickel cobalt composite oxide, lithium vanadium composite oxide, lithium titanium composite oxide, titanium oxide, niobium oxide, vanadium oxide, and tungsten oxide can be used,
Among these, Li _{1 + x} Mn _2-x O ₄ (0 ≦ x ≦ 0.
2), LiMn _2-y Me _y O ₄ (Me = Ni, Cr, C
u, Zn, 0 ≦ y ≦ 0.6), Li ₄ Ti ₅ O ₁₂ , or Li ₄ Mn ₅ O ₁₂ is suitable as an active material because the volume change during charge / discharge is small.

When the positive electrode 2 and the negative electrode 3 are formed by binding active material particles with a binder, for example, stainless steel, aluminum, nickel, copper, kovar, iron,
It can be produced by applying a slurry prepared by kneading an active material, a conductive agent and a binder onto a thin metal plate such as titanium or aluminum alloy and then drying and curing the slurry.

When a sintered body of an active material is used as the positive electrode 2 and the negative electrode 3, a product manufactured by any of the following methods (1) to (3) can be used.
(1) The active material is dispersed in water or a solvent in which a molding aid is dissolved, and if necessary, a plasticizer and a dispersant are mixed to prepare a slurry, and the slurry is applied onto a base film,
After drying, the molded body is peeled from the base film and baked. (2) The active material is directly or granulated and then charged into a mold, and a compact molded by a press is fired.
(3) The granulated active material is pressure-molded by a roll press machine and molded into a sheet, and then fired.

As the molding aid used when preparing the slurry, one or a mixture of two or more of polyacrylic acid, carboxymethyl cellulose, polyvinylidene fluoride, polyvinyl alcohol, diacetyl cellulose, hydroxypropyl cellulose, polyvinyl chloride, polyvinyl pyrrolidone and the like is used. Can be used, and as the base film, for example, a resin film of polyethylene terephthalate, polypropylene, polyethylene, tetrafluoroethylene or the like can be used.

However, the granulation of (2) and (3) may be either wet granulation granulated from the slurry described in the method (1) or dry granulation using no solvent. ,
Further, in the method (2), it is not always necessary to use a molding aid.

A positive electrode collector plate 19 made of a thin metal plate is provided on the surface of the positive electrode 2 opposite to the contact surface with the electrolyte 4 via a conductive adhesive layer 18, and the negative electrode 3 is provided. The negative electrode current collector plate 2 made of a thin metal plate on the surface opposite to the contact surface with the electrolyte 4 via the conductive adhesive layer 18.
0 is set.

The positive electrode current collector 19 and the negative electrode current collector 2
As the material of 0, for example, stainless steel, aluminum,
A thin metal plate such as nickel, copper, kovar, iron, titanium, or aluminum alloy can be used, and may be appropriately selected in consideration of the operating voltage range of each of the electrodes 2 and 3.

As the conductive adhesive 18 for bonding the positive electrode current collector 19 and the positive electrode 2 and the negative electrode current collector 20 and the negative electrode 3 respectively, acrylic resin, epoxy resin, silicon resin, Carbon black, graphite, gold, silver, nickel, zinc oxide in an adhesive composed of at least one polymer adhesive of polyamide resin, phenol resin, polyester resin, polyimide resin or styrene synthetic rubber Of tin oxide, antimony oxide-doped tin oxide, indium oxide, tin oxide-doped indium oxide, antimony-doped tin oxide-coated titanium oxide, antimony-doped tin oxide-coated potassium titanate What contains at least one kind of conductive material may be used.

The positive electrode 2 and the negative electrode 3 are relative ones, and the charge / discharge potentials of the respective active materials are compared with each other. It is sufficient to use the negative electrode 3 having a different potential, and by combining these, the laminated lithium battery 2 having an arbitrary voltage.
1 can be configured.

On the other hand, the electrolyte 4 may be liquid or solid as long as it has ion conductivity. The electrolyte 4 is a polymer solid electrolyte in which an organic electrolyte solution obtained by dissolving an electrolyte salt in an organic solvent or a polymer solid electrolyte is dissolved and polymerized, or a gel in which an organic electrolyte solution and a polymer solid electrolyte are combined. An electrolyte or an inorganic solid electrolyte made of an inorganic material can be used.

When an organic electrolytic solution is used for the electrolyte 4, examples of the organic solvent include ethylene carbonate, propylene carbonate, butylene carbonate, dimethyl carbonate, gamma-butyrolactone, sulfolane, 1,2-dimethoxyethane, 1,3-dimethoxypropane, It is possible to use a solvent selected from the group consisting of dimethyl ether, tetrahydrofuran, 2-methyltetrahydrofuran, dimethyl carbonate, diethyl carbonate, and methyl ethyl carbonate, or a mixture of two or more thereof, and the electrolyte salt may be, for example, LiClO ₄ , LiBF ₄ , LiPF ₆ , LiCF ₃ S
O ₃ , LiN (SO ₂ CF ₃ ) ₂ , LiN (SO ₂ C ₂ F ₅ ) ₂
Lithium salts such as

When an organic electrolytic solution is used as the electrolyte 4, it may be used by impregnating it with a separator. As the separator, for example, a nonwoven fabric made of polyolefin fiber or a microporous membrane made of polyolefin fiber can be used. Here, as the polyolefin fiber, polypropylene,
Examples thereof include polyethylene.

When a polymer solid electrolyte is used as the electrolyte 4, for example, a polymer having a polyethylene oxide skeleton, a polymer having a propylene oxide skeleton, or a mixture and a copolymer thereof is used as the polymer solid electrolyte. You can

When an inorganic solid electrolyte is used as the electrolyte 4, the inorganic solid electrolyte may be, for example, Li _1.3 Al _0.3 Ti ₁₈
(PO _{4) 3} crystalline solid electrolyte such or _{Li 3.6 Ge 0.6 V 0.4 O 4} , 30LiI-41Li 2 O-29P 2 O 5 and 40
It may be an oxide-based amorphous solid electrolytes such as _{Li 2 O-35B 2 O 3} -25LiNbO 3.

Next, a method of manufacturing the power generating element 1 will be described.

When the active material particles hardened with a binder are used as the positive electrode 2 and the negative electrode 3, the positive electrode 2 and the negative current collector with the positive electrode current collector plate 19 formed by the above-described method are used. The negative electrode 3 with the plate 20 is prepared, and as the electrolyte 4, a separator containing an electrolytic solution, a polymer solid electrolyte film, or a solid electrolyte sheet is prepared. Then, the positive electrode 2 is brought into contact with one main surface of the electrolyte 4, and the negative electrode 3 is brought into contact with the other main surface of the electrolyte 4, which are sequentially stacked and pressure-bonded.

When a sintered body of an active material is used as the positive electrode 2 and the negative electrode 3, the above-mentioned (1) to
The positive electrode 2 and the negative electrode 3 are formed by the method of (3), and the positive electrode current collector plate 19 is attached to one main surface of the positive electrode 2 via the conductive adhesive 18, and A negative electrode current collector 20 is attached to one main surface of the negative electrode electrode 3 via a conductive adhesive 18 as well, and a separator containing an electrolytic solution and a polymer solid electrolyte are used as the electrolyte 4. Prepare a film or solid electrolyte sheet. Then, the positive electrode 2 is brought into contact with one main surface of the electrolyte 4, and the negative electrode 3 is brought into contact with the other main surface of the electrolyte 4, which are sequentially stacked and pressure-bonded.

At this time, in order to form the power generating element 1 as shown in FIG. 1, as shown in FIGS. 4 (a) and 4 (b), a plurality of negative electrode materials 23 are arranged side by side at predetermined intervals. After that, an electrolyte 24 is laminated so as to cover them, and a plurality of positive electrode materials 22 are arranged on the electrolyte 24 so as to be orthogonal to the negative electrode material 23 at predetermined intervals, and then they are covered. Further, the electrolyte 24 is laminated. Then, by repeating this operation, a well-shaped laminated body 25 in which a plurality of layers of the negative electrode material 23, the electrolyte 24, the positive electrode material 22, and the electrolyte 24 are stacked in this order is manufactured.

Next, by cutting a portion indicated by a dotted line P where the positive electrode material 22 and the negative electrode material 23 do not intersect, as shown in FIG.
A laminate in which the positive electrode 2 and the negative electrode 3 each having a rectangular planar shape as shown in (c) are arranged so as to intersect with each other, and the electrolyte 4 is provided between the positive electrode 2 and the negative electrode 3. Cut out body 25.

After that, of the cut out laminated body 25,
A conductive resin layer is applied to the end face of the laminate 25 where the positive electrode 2 is exposed to form the positive electrode end face electrode 5, and a conductive resin layer is formed on the end face of the laminate 25 where the negative electrode 3 is exposed. The power generation element 1 is formed by depositing the negative electrode end face electrode 6.

Here, as the conductive resin layer forming the positive electrode end surface electrode 5 and the negative electrode end surface electrode 6, it is preferable to use a material containing a conductive material in a thermoplastic resin. By using a resin layer having thermoplasticity, when the laminated lithium battery 21 is soldered to the circuit board, even if the heat acts on the laminated lithium battery 21, the end face electrodes 5, 6 are laminated 25. Since it is possible to absorb the thermal expansion of the above, peeling or the like does not occur, and it is possible to prevent the occurrence of defective conduction.

As the conductive material for forming the positive electrode end face electrode 5 and the negative electrode end face electrode 6, carbon, graphite (4
0-70μΩ ・ cm), zinc oxide (10 ¹¹ -10 ¹⁶ μΩ)
· Cm), · tin oxide (10 ⁸ μΩ cm), antimony-doped tin oxide ^{(1 × 10 6 ~5 × 10} 6 μΩ · c
m), indium oxide (10 ² to 10 ¹¹ μΩ · cm),
Indium oxide doped with tin oxide (10 ² μΩ · c
m) and titanium carbide (190 μΩ · cm). These conductive materials do not ionize even after repeated charging / discharging and do not elute into the electrolyte to prevent lithium ions from entering and exiting.
It is possible to prevent a decrease in discharge capacity due to repeated charging / discharging and to improve the life of the stacked lithium battery 21.
In order to reduce the resistance inside the battery 21, it is preferable to use carbon having a small resistance value.

Further, as the thermoplastic resin forming the end face electrode 5 for the positive electrode and the end face electrode 6 for the negative electrode, polyethylene terephthalate resin, polybutylene terephthalate resin, and their liquid crystal polymers, polyether ether ketone (PEEK) resin are used. Resin, polyketone sulfide (PKS) resin, engineering plastic such as fluororesin (PFA), polysulfone, polyether sulfone, polyphenylene sulfide (PPS) resin,
Polyhydroxyphenylene ether (PPO) resin,
At least one of a polyamide resin and a polystyrene resin can be mentioned.

As a method of forming the end surface electrodes 5 and 6 made of a conductive resin layer on the end surface of the laminate 25, a method of directly applying a conductive coating material using a dispenser or a base film which has been subjected to a peeling treatment is used. It is possible to use a method in which a conductive paint having a certain width is applied in advance and transferred to the end face of the laminated body 25, a method of masking a portion which should not be conducted and dipping it into the conductive paint tank.

Next, the insulating layer 16 as shown in FIGS. 2 (a) and 2 (b) is formed on the surface 25a of the laminate 25 forming the power generating element 1 facing the base plate 11.

When an adhesive tape is used for the insulating layer 16, the adhesive tape cut into a predetermined shape may be attached to the position of the facing surface 25a of the laminated body 25 facing the base plate 11.

Next, the conductive adhesive 10 is applied on the terminals 14 and 15 of the base plate 11 and a predetermined amount of the adhesive to be the adhesive layer 17 is applied near the central portion, and the power generating element 1 is placed on each terminal. The end electrodes 5 and 6 are electrically connected to the terminals 14 and 15, and the power generation element 1 is bonded to the base plate 11. At this time, the insulating layer 1 is formed on the surface 25a of the power generating element 1 facing the base plate 11.
Since the conductive adhesive 10 is provided on the opposing surface 2
Even if it goes around 5a, no short circuit will occur.

After that, the lid 12 is joined to the base plate 11 through the epoxy resin for sealing and the low melting point glass, and the power generating element 1 is covered with the exterior body 14 composed of the base plate 11 and the lid 12.
It can be obtained by hermetically sealing the inside.

At this time, as the material for forming the lid 12, thermosetting resins such as phenol resin, epoxy resin, imide resin, phenylene ether resin, and allyl resin are used.
Metals such as 2-alloy, Kovar, stainless steel, or insulating ceramics such as aluminum oxide, aluminum nitride, mullite, silicon carbide, silicon nitride, and glass ceramics can be used. In particular, if insulating ceramics are used, airtightness can be obtained. It is possible to provide a highly reliable laminated battery 21 having excellent heat resistance and moisture resistance.

As the material for forming the base plate 11, aluminum oxide, aluminum nitride, mullite,
Insulating ceramics such as silicon carbide, silicon nitride, and glass ceramics can be used. In particular, when using insulating ceramics, a highly reliable laminated battery 21 having excellent airtightness, heat resistance, and moisture resistance is provided. be able to.

In this way, in the obtained laminated lithium battery 21, the power generation element 1 is attached to the base plate 11 by the adhesive layer 17.
Since the power generation element 1 does not shift even if a shock such as a drop is applied, the connection with the terminals 14 and 15 due to the position shift of the power generation element 1 is disconnected. Therefore, it is possible to provide a highly reliable laminated lithium battery 21.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above-mentioned embodiments, and various modifications can be made without departing from the scope of the present invention. Needless to say.

[0072]

As described above, according to the invention of claim 1, a positive electrode, an electrolyte or a separator containing an electrolyte, a negative electrode are provided on a ceramic base plate having a positive electrode terminal and a negative electrode terminal. A power generation element having a positive electrode end face electrode electrically connected to the positive electrode electrode and a negative electrode end face electrode electrically connected to the negative electrode electrode is arranged in a laminated body in which one or more sets of electrode for use are laminated. , While electrically connecting the positive electrode end surface electrode of the power generating element and the positive electrode terminal of the base plate through a conductive adhesive, the negative electrode end surface electrode of the power generating element and the negative electrode terminal of the base plate Which is electrically connected via a conductive adhesive, and a lid body is joined to the base plate to hermetically accommodate the power generation element, and a surface of the laminate facing the base plate. Since an insulating layer is provided on the When joining each end face electrode of the element and each terminal of the base plate with a conductive adhesive, even if the conductive adhesive wraps around to the surface facing the base plate of the power generation element, a short circuit does not occur, and the layers are laminated. Type lithium battery can be manufactured with high yield.

Further, in the above-mentioned power generating element, since the insulating layer adhered to the surface facing the base plate and the base plate are fixed to each other via the adhesive layer, the power generating element can be firmly adhered to the base plate and the impact can be prevented. Even if the power generating element is added, the power generating element does not move inside the outer package, and there is no disconnection between each end surface electrode of the power generating element and each terminal of the base plate, so that a highly reliable laminated lithium battery is provided. You can

Further, since the power generating element is hermetically housed in the exterior body composed of the base plate and the lid, it is possible to use an electrolytic solution as an electrolyte and to provide a laminated lithium battery resistant to heat. it can.

According to the second aspect of the invention, the workability in the manufacturing process of the laminated lithium battery can be improved by using the adhesive tape as the insulating layer.

According to the invention of claim 3, as the adhesive layer, an epoxy resin adhesive, a silicone resin adhesive, an acrylic resin adhesive, a polyimide resin adhesive,
By using at least one kind of insulating adhesive having excellent heat resistance selected from polyamide-imide resin adhesive and phenol resin adhesive, it becomes possible to operate the battery at high temperature.

According to the invention of claim 4, in the power generating element, the positive electrode and the negative electrode have a rectangular planar shape, and when viewed from the stacking direction, the positive electrode and the negative electrode are Since they are laminated so that they cross each other, the distance from each terminal of the base plate to the center of the power generation element can be shortened, so that the internal resistance of the battery can be reduced and the load characteristics can be improved. It is possible to increase the energy density of the laminated lithium battery.

[Brief description of drawings]

1A is a plan view showing an example of a laminated battery of the present invention, FIG. 1B is a sectional view taken along line AA of FIG. 1A, and FIG. 1C is B- of FIG. 1B. A sectional view taken along the line B, (d) is a perspective view showing a stacked state of a power generation element included in the stacked battery of the present invention.

FIG. 2 is a plan view showing an example of a pattern of an insulating layer included in the laminated battery of the present invention.

3 (a) to 3 (d) are plan views showing various patterns of an adhesive layer provided in the laminated battery of the present invention.

4A is a side view for explaining a method for forming the laminated body of FIG. 1D, and FIG. 4B is a side view for explaining a method for forming the laminated body of FIG. It is a top view for doing.

[Explanation of symbols]

1 ... Power generation element 2 ... Positive electrode 3 ... Negative electrode 4 ... Electrolyte 5 ... End face electrode for positive electrode 6 ... End face electrode for negative electrode 10 ... Conductive adhesive layer 11 ... Base plate 12 ... Lid 13 ... Exterior body 14 ... Positive electrode terminal 15 ... Negative electrode terminal 16 ... Insulating layer 17 ... Adhesive layer 18 ... Conductive adhesive layer 19 ... Collector plate for positive electrode 20 ... Current collector for negative electrode 21 ... Layered lithium battery

   ─────────────────────────────────────────────────── ─── Continued front page    F term (reference) 5H022 AA09 BB12 CC16 EE06                 5H029 AJ02 AJ03 AJ06 AJ12 AJ14                       AK02 AK03 AL02 AL03 AM02                       AM03 AM04 AM05 AM07 BJ12                       CJ21 DJ05 DJ07 EJ04 EJ12                 5H050 AA02 AA08 AA12 AA14 AA19                       BA17 CA02 CA05 CA07 CA08                       CA09 CB02 CB03 DA04 DA20                       EA08 EA09 EA12 EA23 EA24                       FA02 GA07

Claims (4)

[Claims] 1. A positive electrode in a laminated body in which one or more positive electrode, electrolyte or separator containing electrolyte, and negative electrode are laminated on a ceramic base plate having a positive electrode terminal and a negative electrode terminal. And a positive electrode end face electrode electrically connected to the negative electrode and a negative electrode end face electrode electrically connected to the negative electrode, respectively. The positive electrode end face electrode of the power generating element and the positive electrode of the base plate are provided. While electrically connecting the for-use terminal through a conductive adhesive, the negative electrode end face electrode of the power generating element and the negative electrode terminal of the base plate are electrically connected through a conductive adhesive, and A laminated lithium battery in which a lid is joined to a base plate to hermetically accommodate the power generation element, wherein an insulating layer is applied to a surface of the laminated body facing the base plate, and the insulating layer and the base plate are attached. And through the adhesive layer Stacked lithium battery is characterized in that so as to. 2. The laminated lithium battery according to claim 1, wherein the insulating layer is an adhesive tape. 3. The adhesive layer is an epoxy resin adhesive,
Silicone resin adhesive, acrylic resin adhesive, polyimide resin adhesive, polyamideimide resin adhesive,
The laminated lithium battery according to claim 1 or 2, comprising at least one kind of insulating adhesive selected from a phenolic resin adhesive. 4. The positive electrode and the negative electrode have a rectangular planar shape, and the positive electrode and the negative electrode are laminated so as to intersect with each other when viewed from the laminating direction. The laminated lithium battery according to any one of claims 1 to 3, which is characterized in that.