JP5481900B2 - Solid secondary battery, method for producing solid secondary battery - Google Patents

Description

  The present invention relates to a solid secondary battery and a method for producing a solid secondary battery.

  Development of a secondary battery that can be repeatedly charged as a power source for a mobile phone or a mobile computer has been underway. Among these secondary batteries, those using organic electrolytes are known, but secondary batteries using organic electrolytes have many side reactions, and there is a risk of liquid leakage and ignition. There was a need for safety considerations.

  A secondary battery using a solid electrolyte (solid secondary battery) has been reported as an attempt to remove the electrolyte (for example, Patent Documents 1 and 2). For example, in the case of a lithium ion secondary battery using a solid electrolyte, the ions that move in the electrolyte by the battery reaction are only lithium ions, so there are almost no side reactions, no flammable organic solution is contained, Since a sealing structure is not required, it is possible to reduce the size and thickness.

JP 2006-277797 A JP 2006-216336 A

  However, in the method of compacting the solid electrolyte powder together with the electrode active material powder as in the solid secondary battery of Patent Document 1, the interface between the solid electrolyte powder and the electrode active material powder or the interface between the solid electrolyte powders is an interface. There was a problem that contact was insufficient and high battery output could not be obtained. In addition, there is a problem that the interface contact becomes unstable due to the volume change accompanying the charge / discharge cycle, and the cycle life is deteriorated.

  On the other hand, as in the solid secondary battery of Patent Document 2, there has been reported one in which a positive electrode thin film, a solid electrolyte thin film, and a negative electrode thin film are sequentially laminated using a vapor phase thin film deposition method such as sputtering. In such a method of laminating thin films, the interface contact between the electrode and the solid electrolyte is good, and the thickness of the active material layer and the solid electrolyte layer can be reduced, so that a high battery output and a good cycle are achieved. Lifetime characteristics can be obtained.

  However, in this method, since the film thickness of each layer is small, the total thickness of the active material layer per unit area is small, and a secondary battery having a large capacity cannot be provided.

  This invention is made | formed in view of such a situation, Comprising: It aims at providing the high output and large capacity solid secondary battery, and its manufacturing method.

To solve the above problems, the present invention includes a first positive electrode collector layer, a first negative electrode collector layer, and the first positive electrode collector layer and the first negative electrode collector layer A first unit battery layer including a first solid electrolyte layer, a second positive electrode current collector layer , a second negative electrode current collector layer , and the second positive electrode current collector A second unit battery layer including a second solid electrolyte layer disposed between the first negative electrode current collector layer and the second negative electrode current collector layer, the first positive electrode current collector layer, and the second positive electrode current collector layer a first conductive member for connecting the positive electrode collector layer, a second conductive member for connecting the first anode current collector layer and the second negative electrode collector layer, the first positive electrode current An adhesive disposed between an electric current layer and the second positive electrode current collector layer , and at least one between the first negative electrode current collector layer and the second negative electrode current collector layer ; , wherein the first positive electrode collector layer Area region and the second region of the positive electrode collector layer, and / or the first negative electrode collector layer region and the second negative electrode current collector layer is of the first solid electrolyte layer The solid secondary battery is larger than the region and the region of the second solid electrolyte layer.
The adhesive may be disposed between the first solid electrolyte layer and the second solid electrolyte layer.
Wherein the first conductive member, the first positive electrode collector layer and disposed so as to penetrate the second positive electrode collector layer, the second conductive member, the first negative electrode collector layer and it may be arranged so as to penetrate the second negative electrode collector layer.
A laminate of a second unit cell layer and the first unit cell layer may be disposed on the third substrate.
The third substrate is made of plastic film, and the third substrate, and a laminate of the first unit cell layer and the second unit cell layer, it is bonded via a second adhesive Also good.
The present invention is a method for manufacturing the above-described solid secondary battery, which includes a first step of forming a first separation layer on a first substrate, and the first solid electrolyte layer on the first separation layer. A second step of forming the first unit cell layer; a third step of forming the second unit cell layer including the second solid electrolyte layer on a second substrate; and the first unit cell. a fourth step of bonding the upper surface of the upper surface of the layer the second unit cell layer by the adhesive, and irradiated with light in the first separation layer, the layer in or the first separation of the first separation layer A fifth step of separating the first substrate and the first unit cell layer by causing separation at an interface with another layer in contact with the layer; and the first unit cell layer and the second unit. connect the positive electrode collector layer between the cell layers in the first conductive member, the negative electrode collector layer same of the first unit cell layer and the second unit cell layer It is a manufacturing method of a solid-state secondary battery which comprises a sixth step of connecting with the second conductive member.
The second substrate has a second separation layer, and in the third step, the second unit cell layer is formed on the second separation layer, and between the fifth step and the sixth step, A seventh step of dividing the second substrate, the second unit cell layer, and the first unit cell layer into two in a state where the second unit cell layer and the first unit cell layer are bonded; and each of the first unit cell layers divided into two An eighth step of bonding the upper surfaces of the second substrate, and irradiating light to the second separation layer of either one of the second substrates, and the other layer in the layer of the second separation layer or in contact with the second separation layer And a ninth step of separating one of the second substrates.
In the solid secondary battery of the present invention, a plurality of unit battery layers each having a solid electrolyte layer sandwiched between a pair of conductive layers are laminated on a substrate via an adhesive, and a plurality of unit battery layers on the positive electrode side are stacked. Conductive layers are connected by a first conductive member, and conductive layers on the negative electrode side are connected by a second conductive member.

  According to this configuration, since one solid secondary battery is formed by a plurality of unit battery layers, even if the solid electrolyte layer of each unit battery layer is thinned, as a whole solid secondary battery, high output, Large capacity.

  In the solid secondary battery of the present invention, it is preferable that the substrate is made of a plastic film, and the substrate and the unit battery layer are bonded via an adhesive.

  According to this configuration, a flexible solid secondary battery can be provided.

  A method for manufacturing a solid secondary battery according to the present invention is a method for manufacturing a solid secondary battery having a plurality of unit battery layers in which a solid electrolyte layer is sandwiched between a pair of conductive layers. A first step of forming one separation layer; a second step of forming a first unit cell layer including a first solid electrolyte layer on the first separation layer; and a second solid electrolyte layer on a second substrate. A third step of forming a second unit cell layer, a fourth step of bonding the upper surface of the first unit cell layer and the upper surface of the second unit cell layer with an adhesive, and applying light to the first separation layer A fifth step of separating the first substrate cell layer and the first unit cell layer by irradiating and causing peeling at a boundary surface between the first separation layer and another layer in contact with the first separation layer. And the positive electrode side conductive layers of the first unit battery layer and the second unit battery layer are connected by a first conductive member, and the negative electrode side conductive layer is the same. The and having a sixth step of connecting the second conductive member.

  According to this method, since one solid secondary battery is formed by a plurality of unit battery layers, even if the solid electrolyte layer of each unit battery layer is thinned, the overall solid secondary battery has a high output, Large capacity.

  In addition, since the unit cell layer is transferred onto the substrate using the separation layer, the unit cell is formed at a lower temperature than when a plurality of unit cell layers are formed on the substrate in the normal solid secondary battery manufacturing process. Layers can be stacked. For example, when a first unit battery layer is formed on a substrate and then a second unit battery layer is formed thereon by a normal solid secondary battery manufacturing process, the first unit battery layer includes a second unit battery layer. A high temperature heat treatment is applied to form the layer. Therefore, for example, a material that cannot be subjected to high-temperature heat treatment such as lithium cannot be used for the first unit battery layer, and material selection is greatly limited.

  On the other hand, in the method for manufacturing a solid secondary battery of the present invention, the heat treatment applied to the first unit battery layer is for curing the adhesive when transferring the second unit battery layer, and for causing the separation layer to peel off. Since only the light irradiation process is involved, the temperature is much lower than when the second unit battery layer is formed directly on the first unit battery layer in the solid secondary battery manufacturing process. Therefore, the range of selection of materials used for the first unit battery layer is widened, and deterioration due to heat treatment is reduced, and a solid secondary battery having very high reliability is provided.

  In the method for manufacturing a solid secondary battery of the present invention, the second substrate has a second separation layer, and in the third step, the second unit cell layer is formed on the second separation layer, Between the 5th step and the 6th step, the 7th step of dividing the second substrate, the second unit cell layer and the first unit cell layer into two in a state where the second substrate cell layer and the first unit cell layer are adhered, And an eighth step of bonding the upper surfaces of the first unit battery layers to each other, irradiating the second separation layer on either one of the second substrates with light in the layer of the second separation layer or the It is desirable to include a ninth step of causing separation at the boundary surface with another layer in contact with the second separation layer to separate one of the second substrates.

  According to this method, it is possible to easily produce a solid secondary battery having four or more unit battery layers.

It is process drawing which shows an example of the manufacturing method of a solid secondary battery. It is process drawing which shows an example of the manufacturing method of a solid secondary battery. It is process drawing which shows an example of the manufacturing method of a solid secondary battery. It is process drawing which shows an example of the manufacturing method of a solid secondary battery. It is process drawing which shows an example of the manufacturing method of a solid secondary battery. It is process drawing which shows an example of the manufacturing method of a solid secondary battery. It is process drawing which shows an example of the manufacturing method of a solid secondary battery. It is process drawing which shows an example of the manufacturing method of a solid secondary battery. It is process drawing which shows an example of the manufacturing method of a solid secondary battery. It is a top view of a solid secondary battery. It is sectional drawing explaining the other structural example of a solid secondary battery. It is sectional drawing explaining the further another structural example of a solid secondary battery.

  FIGS. 1-10 is process drawing which shows 1st Embodiment of the manufacturing method of the solid secondary battery of this invention. The method for manufacturing a solid secondary battery according to the present embodiment includes a step of forming a first separation layer on a first substrate and a step of forming a first unit cell layer including a first solid electrolyte layer on the first separation layer. Forming a second separation layer on the second substrate; forming a second unit battery layer including a second solid electrolyte layer on the second separation layer; and a first unit battery layer and a second unit. At the interface between the step of adhering the battery layer with an adhesive, and the first separation layer irradiated with light through the first substrate, and in the layer of the first separation layer or with another layer in contact with the first separation layer Separating and transferring the first unit battery layer from the first substrate to the second substrate, and bonding the first unit battery layer and the second unit battery layer laminated on the second substrate to the third substrate At the interface between the step of adhering with the agent and the second separation layer with light irradiated through the second substrate, and in the layer of the second separation layer or with another layer in contact with the second separation layer Separating the first unit cell layer and the second unit cell layer from the second substrate to the third substrate, and the first unit cell layer and the second unit cell layer stacked on the third substrate. Connecting the conductive layers on the positive electrode side with the first conductive member and connecting the conductive layers on the negative electrode side with the second conductive member.

  First, as shown in FIG. 1, a first separation layer 101 is formed on a first substrate 100. For example, a quartz glass substrate is used as the first substrate 100, and an a-Si film is used as the first separation layer 101. However, the first substrate 100 is not limited to this.

  The first separation layer 101 is peeled off at a boundary surface between the first separation layer 101 and another layer in contact with the first separation layer 101 by a light irradiation process described later. Since the first separation layer 101 is irradiated with light from the first substrate 100 side, it is desirable that the first substrate 100 is sufficiently transparent to light. Specifically, the first substrate 100 preferably transmits 10% or more of light, and more preferably transmits 50% or more.

  When the first separation layer 101 is made of a-Si, ultraviolet light using an excimer laser or the like as a light source can be used as light. In such a case, as a material constituting the first substrate 100, It is preferable to use a material that sufficiently transmits ultraviolet light, such as glass or quartz glass.

Although the thickness of the 1st board | substrate 10 is not specifically limited, From the balance of the mechanical strength of a board | substrate and the amount of light transmission, it is preferable that it is about 0.1-5.0 mm, and 0.5-1. It may be more preferable that it is 5 mm. If the light transmittance of the first substrate 100 is sufficiently high, the thickness may exceed the upper limit. In order to uniformly irradiate the first separation layer 101 with light, the thickness of the first substrate 100 is preferably uniform. When forming either the first separation layer 101 or the first unit cell layer formed on the first substrate 100, if the high temperature treatment is required, the first substrate 100 has sufficient heat resistance. It is preferable to have. Specifically, the highest temperature for forming the first separating layer 101 and the first unit cell layer is taken as T _max, it is desirable that the strain point is constituted by a T _max or more materials.

  As a material used for the 1st separated layer 101, the material described in the following AF can be used, for example.

A. Amorphous silicon (a-Si)
Amorphous silicon may contain hydrogen. In this case, the hydrogen content is preferably about 1 at% or more, more preferably about 2 to 20 at%. As described above, when a predetermined amount of hydrogen is contained, hydrogen is released by light irradiation, and an internal pressure is generated in the first separation layer 20, which becomes a force that promotes peeling. The content of hydrogen in amorphous silicon is adjusted by appropriately setting film forming conditions such as gas pressure, gas atmosphere, gas flow rate, temperature, substrate temperature in CVD, and input power for plasma generation. can do.

B. Various oxide ceramics such as silicon oxide or silicic acid compound, titanium oxide or titanic acid compound, lanthanum oxide or lanthanum acid compound, dielectric, ferroelectric or semiconductor Silicon oxide includes SiO, SiO2, Si302 Examples of the silicate compound include K2SiO3, Li2SiO3, CaSiO3, ZrSiO4, and Na2SiO3. Examples of the titanium oxide include TiO, Ti203, and TiO2, and examples of the titanic acid compound include BaTiO4, BaTiO3, Ba2Ti9020, BaTi5011, CaTiO3, SrTiO3, PbTiO3, MgTiO3, ZrTiO2, SnTiO4, A12TiO5, and FeTiO3. Examples of the zirconium oxide include ZrO2, and examples of the zirconate compound include BaZrO3, ZrSiO4, PbZrO3, MgZrO3, and K2ZrO3.

C ・ PZT [Pb (Zr, Ti) O3]], PLZT [(Pb, La) (Zr, Ti) O3]], ceramics or dielectrics (ferroelectric) such as PLLZT and PBT

D. Nitride ceramics such as silicon nitride, aluminum nitride, titanium nitride

E. Organic polymer materials Organic polymer materials include one CH-, -CO- (ketone), -CONH- (amide), -NH one (amino), -COO- (ester) on the main chain of the polymer. , -N = N- (azo), and -CH = N- (imide). In addition, an organic polymer in which an aromatic hydrocarbon such as benzene or naphthalene is incorporated can be used to improve the amount of light absorption. Specific examples of such organic polymer materials include polyolefins such as polyethylene and polypropylene, polyimides, polyamides, polyesters, polymethyl methacrylate (PMMA), polyphenylene sulfide (PPS), and polyether sulfone (PES). , Polyester terephthalate (PET), and epoxy resin.

F. Examples of the metal include Al, Li, Ti, Mn, In, Sn, Y, La, Ce, Nd, Pr, Gd, Sm, or an alloy containing at least one of these. A multilayer film in which these metals are stacked on an amorphous silicon film can also be used as the first separation layer 101.

  The thickness of the first separation layer 101 varies depending on various conditions such as the composition and material of the first separation layer, the laminated structure, and the forming method, but it is usually preferably about 1 nm to 20 μm, and about 10 nm to 2 μm. More preferably, it is about 40 nm to 1 μm.

  The formation method of the 1st separated layer 101 can be suitably selected according to various conditions, such as a film composition and a film thickness. For example, various vapor phase growth methods such as CVD (including MOCVD, low pressure CVD, ECR-CVD, plasma CVD), vapor deposition, molecular beam vapor deposition (MB), sputtering, ion plating, PVD, electroplating, immersion plating, dipping , Various plating methods such as electroless plating, Langmuir-Blodget (LB) method, spin coating, spray coating, roll coating and other coating methods, various printing methods, transfer methods, inkjet methods, powder jet methods, and the above Two or more methods selected from the methods can be combined to form.

  For example, when the composition of the first separation layer 20 is amorphous silicon (a-Si), it is preferable to form the film by a CVD method, in particular, a low pressure CVD method or a plasma CVD method. Further, when the first separation layer 20 is made of ceramics by a sol-gel method or made of an organic polymer material, it is preferable to form a film by a coating method, particularly a spin coating method.

  Next, as shown in FIG. 2, a first positive electrode wiring layer (conductive layer) 102 is formed on the first separation layer 101, and a first positive electrode current collector layer (conductive layer) is formed on the first positive electrode wiring layer 102. ) 103, a platinum film is formed by vapor deposition or sputtering.

  The first positive electrode wiring layer 102 and the first positive electrode current collector layer 103 are not particularly limited as long as they are conductive materials. For example, what processed aluminum, copper, nickel, stainless steel material, etc. into metal foil, electrolytic foil, rolled foil, an embossed product, a foam sheet, etc. can be used. The thickness of the first positive electrode current collector layer 103 is not particularly limited, but is usually 5 to 30 μm.

Next, as shown in FIG. 3, a LiMn ₂ O ₄ film is formed as a first positive electrode active material layer 104 on the first positive electrode current collector layer 103 by a sol-gel method.

  As the sol-gel solution, a solution in which 10 wt% of lithium acetate and manganese acetate mixed so that the material cost of lithium and manganese is 1: 2 is dissolved in methanol.

There is no restriction | limiting in particular in the material of the 1st positive electrode active material layer 104, A well-known thing can be used. For example, when forming a positive electrode for a lithium battery, a Li—Mn composite oxide such as LiMn ₂ O _4, a Li—Co composite oxide such as LiCoO ₂ , and a Li—Ni composite oxide such as LiNiO ₂ Things. These positive electrode active materials can be used alone or in combination of two or more. The thickness of the first positive electrode active material layer 104 is preferably 100 nm to 1 μm.

Subsequently, a SiO ₂ · P ₂ O ₅ film is formed as the first solid electrolyte layer 105 on the first positive electrode active material layer 104.

As a material of the first solid electrolyte, for example, an SOG (Spin On Glass) material manufactured by High-Purity Science Laboratory Co., Ltd. is applied by spin coating, and then baked at 500 ° C. to obtain SiO ₂ · P ₂ O. _Five films can be formed. As a coating method, in addition to the spin coating method, various printing methods such as an inkjet method, a screen printing method, and a nanoimprint method can be used. The thickness of the first solid electrolyte layer 105 is desirably 10 nm to 500 nm.

The first solid electrolyte layer _{105, Li 2 S-B 2 S} 3 based inorganic _materials, Li ₂ S-SiS 2 based inorganic _{materials, Li 2 S-P 2 S} 5 based inorganic materials _{Li 2 S-GeS} 2 -P 2 S ₅ based inorganic _{materials, LiI-Li 2 S-P} 2 S 5 based inorganic _{materials, LiI-Li 2 S-SiS} 2 based inorganic _{materials, LiBr-Li 2 S-SiS} 2 based inorganic materials, _LiI-Li 2 S- B ₂ S ₃ based inorganic materials, LiBH ₄ based inorganic _{materials, Li 3 PO 4 -Li 2 S} -SiS 2 based inorganic materials, LISICON inorganic _{material, Li 14 Zn (GeO 4)} 4 based inorganic materials, _Li 2 S- SiS ₂ -Li ₄ SiO ₄ based inorganic _{materials, Li 1.3 -Al 0.3 -Ti 1.7 -} (PO 4) 3 based inorganic materials, thio-LISICON inorganic _material, Li 3.4 _{-V 0. 4-} Ge _0.6 series inorganic material Material, La _0.51 -Li _0.34- TiO _2.94 inorganic material, Li ₂ O—B ₂ O ₃ —LiCl inorganic material, Li ₂ O—Nb ₂ O ₅ inorganic material, NASICON inorganic material , SiO ₂ · P ₂ O ₅ -based inorganic material, Li ₂ O-SiO ₂ -based inorganic material, SiO ₂ · P ₂ O ₅ -based inorganic material, one or a mixture of two or more of SiO ₂ -based inorganic materials, compounds be able to. If necessary, fine particles such as alumina can be added to these materials in an amount of 0.01% to 10%.

  The first solid electrolyte layer 105 can also be formed by powder compression or hot press. Further, it can be formed by a sol-gel method using a sol-gel solution or a method of applying and baking a fine particle dispersion solution. Alternatively, it can be formed using a vapor phase film forming method such as a CVD method or a sputtering method.

  Next, as illustrated in FIG. 4, a silicon oxide film is formed as a first insulating layer 106 by a sputtering method in a portion where the first positive electrode active material layer 105 is not formed.

  The first insulating layer 106 is for preventing a short circuit between the first positive electrode wiring layer 102 and a first negative electrode wiring layer 108 described later. As the first insulating layer 106, an inorganic oxide film such as silicon oxide, polysiloxane, or polysilazane is preferably used.

  Next, as shown in FIG. 5, a lithium film is formed as the first negative electrode active material layer 107 on the first solid electrolyte layer 105, and the first negative electrode active material layer 107 is further formed on the first negative electrode active material layer 107. As the electric conductor layer (conductive layer) and the first negative electrode wiring layer (conductive layer) 108, an aluminum film is formed by an evaporation method.

  There is no restriction | limiting in particular in the material of the 1st negative electrode active material layer 107, A well-known thing can be used. For example, when forming a negative electrode for a lithium battery, metals such as lithium and titanium, and alloys thereof; natural graphite, artificial graphite, carbon black, activated carbon, carbon fiber, coke, soft carbon, hard carbon, graphite, etc. Carbon materials; and the like. These negative electrode active materials can be used alone or in combination of two or more. The thickness of the first negative electrode active material layer 107 is desirably 100 nm to 1 μm.

  Note that the first negative electrode active material layer 107 can also be formed by powder compression formation or hot press formation. Further, it can be formed by a sol-gel method using a sol-gel solution or a method of applying and baking a fine particle dispersion solution. Alternatively, it can be formed using a vapor phase film forming method such as a CVD method or a sputtering method.

  The first negative electrode current collector layer and the first negative electrode wiring layer 108 are not particularly limited as long as they are conductive materials. For example, what processed aluminum, copper, nickel, stainless steel material, etc. into metal foil, electrolytic foil, rolled foil, an embossed product, a foam sheet, etc. can be used.

  Thus, on the first separation layer 101, the first positive electrode wiring layer 102, the first positive electrode current collector layer 103, the first positive electrode active material layer 104, the first solid electrolyte layer 105, the first insulating layer 106, the first insulating layer 106, A first unit battery layer A is formed by laminating the first negative electrode active material layer 107, the first negative electrode current collector layer, and the first negative electrode wiring layer.

  The first positive electrode wiring layer 102, the first positive electrode current collector layer 103, the first positive electrode active material layer 104, the first solid electrolyte layer 105, the first insulating layer 106, the first negative electrode active material layer 107, the first negative electrode The stacking order of the current collector layer and the first negative electrode wiring layer 108 is not limited to that shown in FIG. 5, and the stacking order may be reversed. In this case, on the first separation layer 101, the first negative electrode current collector layer 108, the first negative electrode active material layer, the first insulating layer 106, the first solid electrolyte layer 105, the first positive electrode active material layer 104, the first The first positive electrode current collector layer 103 and the first positive electrode wiring layer 102 are laminated in this order.

  Next, as shown in FIG. 6, the second separation layer 111 is formed on the second substrate 110, and the second positive electrode wiring layer 112, the second positive electrode current collector layer 113, and the second separation layer 111 are formed on the second separation layer 111. Second unit battery layer B including two positive electrode active material layers 114, second solid electrolyte layer 115, second insulating layer 116, second negative electrode active material layer 117, second negative electrode current collector layer and second negative electrode wiring layer 118. Form.

  The method of forming the second unit battery layer B can be the same as that of the first unit battery layer A.

  Subsequently, the adhesive 109 is disposed between the first unit battery layer A and the second unit battery layer B, and the adhesive 109 is cured to bond them together.

  As the adhesive 109, various curable adhesives such as a reactive curable adhesive, a thermosetting adhesive, a photocurable adhesive such as an ultraviolet curable adhesive, and an anaerobic curable adhesive can be used. In particular, it is preferable to use a photocurable adhesive from the viewpoint of reducing the cycle time of the process. As said photocurable material, an epoxy type, an acrylate type, and a silicone type photocurable material can be used, for example. When the adhesive 109 needs to be finally removed, the adhesive 109 is preferably soluble in a solvent, and particularly preferably water-soluble. As a material that satisfies the above conditions, for example, ThreeBond 3046 (trade name) can be used.

  Next, as shown in FIG. 7, the first separation layer 101 is irradiated with light L <b> 1 through the first substrate 100, and the first separation layer 101 is in contact with the other layers in contact with the first separation layer 101. The first unit battery layer A is transferred from the first substrate 100 to the second substrate 110 by causing peeling at the boundary surface.

As the light L1 that induces peeling in the first separation layer 101, X-rays, ultraviolet rays, visible light, infrared rays (heat rays), millimeter waves, microwaves, electron beams, radiations (depending on the properties of the first separation layer 101) Light of various wavelengths such as α wave, β wave, and γ wave) or electromagnetic waves can be used. When it is necessary to control the irradiation area or irradiation region, it is preferable to use a laser that oscillates light of these wavelengths or electromagnetic waves with excellent directivity. Examples of the laser include various gas lasers, glass lasers, and semiconductor lasers. More specifically, for example, excimer laser, Nd-YAG laser, Ar laser, Kr laser, CO ₂ laser, CO laser, and A He—Ne laser can be mentioned.

When an amorphous silicon film is used as the first separation layer 101, ultraviolet light using an excimer laser or the like as a light source can be used as the light L1. Since amorphous silicon exhibits strong absorption with respect to light having a wavelength range of about 320 nm or less, it is desirable to use a wavelength range of 100 nm to 350 nm as the wavelength of the light L1. When high-power ultraviolet light using an excimer laser as a light source is used for irradiation of the first separation layer 101, a peeling phenomenon in the first separation layer 101 can be induced in an extremely short time. Therefore, secondary effects induced by light irradiation on the first separation layer 101 such as temperature rise, deterioration, or damage of adjacent layers such as the first unit battery layer A can be reduced. Incidentally, the energy density of the light L1 is preferably set to 10~5000mJ / cm ² or so, and more preferably, 100 to 500 mJ / cm ² or so. The irradiation time is preferably about 1 to 1000 nanoseconds, and more preferably about 10 to 100 nanoseconds.

  It is desirable that hydrogen be contained in the amorphous silicon film. In this case, the hydrogen content is preferably about 1 at% or more, and more preferably about 2 to 20 at%. As described above, when a predetermined amount of hydrogen is contained, hydrogen is released by irradiation with the light L1, and an internal pressure is generated in the amorphous silicon film, which becomes a force for promoting peeling. The content of hydrogen in the amorphous silicon film can be determined by appropriately setting conditions such as film formation conditions such as gas pressure, gas atmosphere, gas flow rate, temperature, substrate temperature, and input power for plasma generation in the CVD method. Can be adjusted.

  In addition, after performing light irradiation with respect to the 1st separated layer 101, a part or all of the 1st separated layer 101 may adhere to the 1st unit battery layer A. In this case, for example, the deposits on the first unit battery layer A can be removed by performing a method such as cleaning, etching, ashing, polishing, or a combination thereof.

  Next, as shown in FIG. 8, an adhesive 121 is disposed between the second unit battery layer B and the third substrate 120, and the adhesive 121 is cured to bond them together.

  As the third substrate 120, various materials such as metal, ceramics, stone, wood, paper, and the like can be used, but in particular, by using a resin material excellent in lightness, flexibility, elasticity, etc. These mechanical properties can be imparted to the manufactured laminate, and the material cost and manufacturing cost can also be reduced.

  As the adhesive 121, similarly to the adhesive 109, various curable adhesives such as a reactive curable adhesive, a thermosetting adhesive, a photocurable adhesive such as an ultraviolet curable adhesive, and an anaerobic curable adhesive. Can be used.

  Subsequently, the second separation layer 111 is irradiated with the light L2 through the second substrate 110 to cause separation at the interface of the second separation layer 111 or another layer in contact with the second separation layer 111. The first unit battery layer A and the second unit battery layer B stacked on the second substrate are transferred from the second substrate 110 to the third substrate 120.

  As the light L2, similarly to the light L1, ultraviolet light using an excimer laser or the like as a light source can be used.

  Next, as shown in FIGS. 9 and 10, the first positive electrode wiring layer 102 and the second positive electrode wiring layer 112 are electrically connected by the first conductive member 122, and the first negative electrode wiring layer 108 and the second negative electrode wiring layer are connected. The wiring layer 118 is electrically connected by the second conductive member 123.

  The connection between the first positive electrode wiring layer 102 and the second positive electrode wiring layer 112 is performed, for example, by drilling a portion where both are overlapped and connecting the two through a conductive member such as solder. At this time, in order to facilitate drilling, the first positive electrode wiring layer 102 and the second positive electrode wiring layer 112 are formed wider than the formation region of the first solid electrolyte layer 105 and the second solid electrolyte layer 115. The connection between the first negative electrode wiring layer 108 and the second negative electrode wiring layer 118 is the same.

  Next, as a sealing member for shielding the first unit battery layer A and the second unit battery layer B from the atmosphere, a resin film such as an epoxy resin is formed on the surface of the third substrate 120 (not shown) to form a solid. The secondary battery 1 is completed. In addition, as a sealing means, the method of apply | coating sealing resin on the surface of the 1st unit battery layer A and the 2nd unit battery layer B, and affixing sealing substrates, such as a glass substrate, 1st unit battery layer A Alternatively, a method of confining the second unit battery layer B in a metal can may be used.

  According to the method for manufacturing a solid secondary battery of the present embodiment, since one solid secondary battery is formed by a plurality of unit battery layers, even if the solid electrolyte layer of each unit battery layer is thinned, the solid secondary battery is formed. The secondary battery as a whole has a high output and a large capacity. In addition, since the plurality of unit battery layers A and B are transferred onto the third substrate 120 made of a plastic film, a flexible solid secondary battery can be provided.

  In addition, since the unit cell layers A and B are transferred onto the third substrate 120 using the separation layers 101 and 111, a plurality of unit cell layers A are formed on the third substrate 120 in a normal solid secondary battery manufacturing process. , B, the unit battery layers A, B can be stacked at a lower temperature. For example, when the first unit battery layer A is formed on the third substrate 120 and then the second unit battery layer B is formed on the first unit battery layer A by a normal solid secondary battery manufacturing process, Is subjected to a high-temperature heat treatment for forming the second unit battery layer B. Therefore, for example, a material that cannot be subjected to high-temperature heat treatment such as lithium cannot be used for the first unit battery layer A, and material selection is greatly limited.

  On the other hand, in the method for manufacturing a solid secondary battery according to the present embodiment, the heat treatment applied to the first unit battery layer A includes the curing process of the adhesive 109 when transferring the second unit battery layer B, and the first separation layer 101. As compared with the case where the second unit battery layer B is formed directly on the first unit battery layer A in the solid secondary battery manufacturing process, it is only an incidental to the light irradiation treatment for causing peeling. The temperature becomes very low. Therefore, the range of selection of materials used for the first unit battery layer A is widened, and deterioration due to heat treatment is reduced, so that a solid secondary battery with extremely high reliability is provided.

  In this embodiment, the first unit battery layer A and the second unit battery layer B are formed on separate substrates, and both are bonded with an adhesive, but the unit cell layer is formed on one substrate, The substrate may be divided into a plurality of parts, and the unit battery layers of one divided substrate and another substrate may be bonded with an adhesive. In this case, the first unit cell layer A having the shape of the first positive electrode wiring layer 102 and the first negative electrode wiring layer 108 shown in FIG. 10 is formed in the first region on one substrate, and the first region is formed. A second unit battery layer B having the shape of the second positive electrode wiring layer 112 and the second negative electrode wiring layer 118 shown in FIG. 10 is formed in the second region that does not overlap with the second region. And a 1st area | region and a 2nd area | region are divided | segmented and both are bonded together with an adhesive agent. When such a method is used, a plurality of unit battery layers having the same quality can be easily produced in a short time, and the manufacturing process of the solid secondary battery can be greatly simplified.

  FIG. 11 is a cross-sectional view of a second embodiment of the solid secondary battery of the present invention. The solid secondary battery 2 of the present embodiment is obtained by bonding two solid secondary batteries 1 shown in FIG.

  When manufacturing the solid secondary battery 2, first, the first unit battery layer A and the second unit battery layer B are formed on the second substrate 110 by using the method shown in FIGS. 1 to 7. Further, the first unit battery layer A and the second unit battery layer B are formed on the fourth substrate 130 by the same method.

  The first unit battery layer A and the second unit battery layer B formed on the second substrate 110, and the first unit battery layer A and the second unit battery layer B formed on the fourth substrate 130. An adhesive 126 is disposed between them, and the adhesive 126 is heated and cured to bond them together.

  Subsequently, the second separation layer 111 is irradiated with light through the second substrate 130 to cause peeling at the interface between the second separation layer 111 and another layer in contact with the second separation layer, The first unit battery layer A and the second unit battery layer B stacked on the second substrate 110 are transferred from the second substrate 110 to the fourth substrate 130.

  Then, the positive electrode wiring layers of the unit battery layers A and B are connected by the first conductive member 124, and the negative electrode wiring layers are connected by the second conductive member 125. Then, a resin film such as an epoxy resin is formed on the surface of the fourth substrate 130 (not shown) as a sealing film for blocking the unit battery layers A and B from the atmosphere, and the solid secondary battery 2 is completed. .

  In the case where the unit battery layers A and B are formed on a flexible fifth substrate such as a plastic film substrate, a separation layer is formed in advance on the surface of the fourth substrate 130, and the four stacked on the fourth substrate. The unit battery layers A and B are bonded to the fifth substrate. Then, the separation layer is irradiated with light through the fourth substrate 130 to cause peeling at the boundary surface between the separation layer and another layer in contact with the separation layer, and the layers 4 stacked on the fourth substrate 130. The two unit battery layers A and B are transferred from the fourth substrate 130 to the fifth substrate.

  According to the method for producing a solid secondary battery of the present embodiment, a solid secondary battery having four or more unit battery layers can be easily produced. In FIG. 11, four unit cell layers are stacked on the fourth substrate 130, but it is easy to stack two or more than four solid secondary batteries 2 of FIG. 11 using the same method. A solid secondary battery having multiple unit battery layers can be produced.

  FIG. 12 is a cross-sectional view of a third embodiment of the solid secondary battery of the present invention. The solid secondary battery 3 of the present embodiment is obtained by stacking five layers of unit battery layers A and C having the configuration shown in FIG. 5 on a substrate 140 via an adhesive 144.

  In each unit battery layer A, C, a positive electrode wiring layer 141, a battery layer 142 (positive electrode current collector layer, positive electrode active material layer, solid electrolyte layer, negative electrode active material layer, negative electrode current collector layer), negative electrode wiring layer 143 The stacking order is the same for all. In any unit battery layer, these layers are laminated in order from the substrate side. For the adhesive 144 disposed between the unit battery layers, an insulating adhesive is used so that the positive electrode wiring layer 141 and the negative electrode wiring layer 143 are not short-circuited.

  When manufacturing the solid secondary battery 3 of FIG. 12, first, the first unit battery layer A is formed on the first substrate 100 using the steps of FIGS. 1 to 5. Further, a positive electrode wiring layer, a positive electrode current collector layer, a positive electrode active material layer, a solid electrolyte layer, a negative electrode active material layer, a negative electrode current collector layer, and a negative electrode wiring layer are formed on a substrate (not shown) different from the first substrate 100. A second unit battery layer C having a different stacking order from the first unit battery layer A is formed. In the second unit battery layer C, a negative electrode wiring layer, a negative electrode current collector layer, a negative electrode active material layer, a solid electrolyte layer, a positive electrode active material layer, a positive electrode current collector layer, and a sex electrode wiring layer are laminated in order from the substrate side. The

  Next, the first unit battery layer A and the second unit battery layer C are bonded with an adhesive 144, and the first separation layer 101 is irradiated with light from the first substrate 100 side. Alternatively, peeling occurs at the boundary surface with the other layer in contact with the separation layer, and the first unit battery layer A is transferred from the first substrate 100 to the other substrate. Then, by repeating the same process, finally, the five unit battery layers A and C are laminated on the substrate 140 via the adhesive 144. In the five unit battery layers A and C that are stacked, the positive electrode wiring layers are connected by the first conductive member 145, and the negative electrode wiring layers are connected by the second conductive member 146. And unit battery layer A, C is sealed with a sealing member as needed, and the solid secondary battery 3 is completed.

1, 2, 3 ... solid secondary battery, 100, 110, 120, 130, 140 ... substrate, 101, 111 ... separation layer, 102, 112 ... positive electrode wiring layer, 103, 113 ... positive electrode current collector layer, 104, 114: positive electrode active material layer, 105, 115 ... solid electrolyte layer, 107, 117 ... negative electrode active material layer, 108, 118 ... negative electrode current collector layer and negative electrode wiring layer, 109, 121, 126, 144 ... adhesive, 122 , 123, 124, 125, 145, 146 ... conductive members, A, B, C ... unit cell layers, L1, L2 ... light

Claims (7)

The first positive electrode collector layer, a first negative electrode collector layer, the first solid electrolyte layer disposed between said first positive electrode collector layer and the first negative electrode collector layer A first unit cell layer comprising:
The second positive electrode collector layer, a second negative electrode collector layer, a second solid electrolyte layer disposed between said second positive electrode collector layer and the second negative electrode collector layer A second unit cell layer comprising:
A first conductive member connecting the first positive electrode current collector layer and the second positive electrode current collector layer ;
A second conductive member connecting the first negative electrode current collector layer and the second negative electrode current collector layer ;
Between at least one of the first positive electrode current collector layer and the second positive electrode current collector layer and between the first negative electrode current collector layer and the second negative electrode current collector layer; An adhesive to be disposed,
The region of the first positive electrode current collector layer and the region of the second positive electrode current collector layer and / or the region of the first negative electrode current collector layer and the region of the second negative electrode current collector layer Is larger than the region of the first solid electrolyte layer and the region of the second solid electrolyte layer.   The solid secondary battery according to claim 1, wherein the adhesive is disposed between the first solid electrolyte layer and the second solid electrolyte layer. The first conductive member is disposed so as to penetrate the first positive electrode current collector layer and the second positive electrode current collector layer ,
Said second conductive members, solid state secondary of claim 1 or 2, wherein the first negative electrode collector layer and disposed so as to penetrate the second negative electrode collector layer, wherein the Turkey Next battery. The solid secondary battery according to any one of claims 1 to 3, wherein the first unit battery layer and the second unit battery layer are stacked on a third substrate. . The third substrate is made of plastic film, and the third substrate, and a laminate of the first unit cell layer and the second unit cell layer, it is bonded via a second adhesive The solid secondary battery according to claim 4, wherein: A method for producing a solid secondary battery according to any one of claims 1 to 5,
A first step of forming a first separation layer on the first substrate;
A second step of forming the first unit cell layer including the first solid electrolyte layer on the first separation layer;
Forming a second unit cell layer including the second solid electrolyte layer on a second substrate;
A fourth step of bonding the upper surface of the upper surface and the second unit cell layer of the first unit cell layer with the adhesive,
The first separation layer is irradiated with light to cause peeling at a boundary surface between the first separation layer or another layer in contact with the first separation layer, and the first substrate and the first unit. A fifth step of separating the battery layer;
Anode current of the first unit cell layer positive electrode collector layer between the second unit cell layer are connected by the first conductive member, the first unit cell layer and the second unit cell layer sixth step and a method for manufacturing a solid-state secondary battery which comprises a connecting the conductor layers to each other by the second conductive member. The second substrate has a second separation layer;
In the third step, the second unit cell layer is formed on the second separation layer,
Between the fifth step and the sixth step,
A seventh step of dividing the second substrate, the second unit cell layer, and the first unit cell layer into two in a state where the second unit cell layer and the first unit cell layer are bonded;
An eighth step of bonding the upper surfaces of the first unit cell layers divided into the two parts;
Irradiating light to the second separation layer of either one of the second substrates, causing peeling at a boundary surface with the second separation layer or another layer in contact with the second separation layer, And a ninth step of separating one of the second substrates. The method of manufacturing a solid secondary battery according to claim 6.

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