JPWO2019077664A1 - Electrolyte sheet, battery member for secondary battery and secondary battery, and manufacturing method of these - Google Patents

Abstract

The present invention provides, as one aspect, an electrolyte sheet comprising an electrolyte layer and a pressure-sensitive adhesive layer provided on at least a part of the main surface of the electrolyte layer.

Description

The present invention relates to an electrolyte sheet, a battery member for a secondary battery, a secondary battery, and a method for manufacturing the same.

In recent years, with the spread of portable electronic devices, electric vehicles, etc., high-performance secondary batteries are required. Among them, the lithium secondary battery has a high energy density, and is therefore attracting attention as a power source for electric vehicle batteries, power storage batteries, and the like. Specifically, lithium secondary batteries as batteries for electric vehicles include zero-emission electric vehicles that do not have an engine, hybrid electric vehicles that have both an engine and a secondary battery, and plug-in hybrids that charge directly from the power system. It is used in electric vehicles such as electric vehicles. Further, a lithium secondary battery as a power storage battery is used in a stationary power storage system or the like that supplies power stored in advance in an emergency when the power system is cut off.

Among such secondary batteries, in particular, lithium secondary batteries for electric vehicles are required to have high safety in addition to high input / output characteristics and high energy density, so that safety can be ensured. More advanced technology is required. Therefore, as a more safe lithium secondary battery, a solid electrolyte battery in which the electrolyte is changed to a solid electrolyte such as a gel electrolyte has been developed.

Patent Document 1 discloses a battery using a gel-like electrolyte layer containing a plasticizer containing a lithium salt, a matrix polymer in which the plasticizer is dispersed, and a fibrous insoluble matter. Patent Document 2 discloses a battery using a gel electrolyte formed by swelling a matrix polymer with an electrolytic solution. In Patent Document 3, a pressure-sensitive adhesive is inserted between the sheet-shaped porous base material and the electrode material, and the sheet-shaped porous base material is filled with the electrode material and the pressure-sensitive adhesive by applying pressure in an integrated state. A lithium ion battery in which an electrode sheet and a solid electrolyte layer are laminated on the electrode sheet is disclosed.

Japanese Unexamined Patent Publication No. 2000-164254 JP-A-2007-141467 JP-A-2015-153459

In such a solid electrolyte battery, an electrolyte layer is laminated between the positive electrode and the negative electrode, but in the conventional production of a solid electrolyte battery, when the electrolyte layer is laminated with the electrode, each layer is wrinkled or wavy. May occur. In particular, in the case of a wound type secondary battery, since a long electrode and an electrolyte layer are wound to form an electrode group, the adverse effect of wrinkles or waviness is large, and the performance of the secondary battery may be significantly impaired. There is. As described above, even if the electrolyte sheet itself has excellent performance, the performance of the electrolyte sheet may not be sufficiently exhibited because the technique for appropriately laminating the electrode and the electrolyte layer has not been established.

Therefore, an object of the present invention is to provide an electrolyte sheet capable of suitably laminating an electrolyte layer with an electrode, a battery member for a secondary battery and a secondary battery using the electrolyte sheet, and a method for producing these. And.

The present invention provides, as a first aspect, an electrolyte sheet comprising an electrolyte layer and a pressure-sensitive adhesive layer provided on at least a part of the main surface of the electrolyte layer.

The electrolyte sheet may further include an elongated base material, and the electrolyte layer may be an elongated electrolyte layer provided on the main surface of the base material.

A plurality of pressure-sensitive adhesive layers may be provided on the main surface of the electrolyte layer opposite to the base material at predetermined intervals in the longitudinal direction of the electrolyte layer.

Each of the plurality of pressure-sensitive adhesive layers may have an elongated shape extending along the lateral direction of the electrolyte sheet.

Each of the plurality of pressure-sensitive adhesive layers may have an elongated shape extending along the longitudinal direction of the electrolyte sheet.

The electrolyte sheet may further include a protective layer provided on the electrolyte layer and the pressure-sensitive adhesive layer.

The electrolyte sheet may further include a release layer on the surface opposite to the electrolyte layer of the base material.

The pressure-sensitive adhesive layer may be provided at one end of the electrolyte layer.

The pressure-sensitive adhesive layer may be provided so as to cover the entire edge of one end of the electrolyte layer.

The thickness of the electrolyte layer in the region where the pressure-sensitive adhesive layer is provided may be reduced toward the edge.

The electrolyte layer contains one or more types of polyma, oxide particles, at least one electrolyte salt selected from the group consisting of lithium salt, sodium salt, calcium salt, and magnesium salt, and a solvent. You can do it.

The pressure-sensitive adhesive layer may contain at least one selected from the group consisting of acrylic resin, methacrylic resin, silicone resin, urethane resin, polyvinyl ether, and styrene-butadiene rubber.

The present invention provides, as a second aspect, an electrolyte sheet wound body including a winding core and the above-mentioned electrolyte sheet wound around the winding core.

In the third aspect of the present invention, a step of providing a long electrolyte layer on the main surface of the long base material and a longitudinal direction of the electrolyte layer on the surface of the electrolyte layer opposite to the base material. Provided is a method for producing an electrolyte sheet, comprising a step of providing a plurality of pressure-sensitive adhesive layers at predetermined intervals.

As a fourth aspect of the present invention, the current collector, the electrode mixture layer provided on the main surface of the current collector, and the electrode mixture layer provided on the surface opposite to the current collector. Provided is a battery member for a secondary battery, which comprises an electrolyte layer, and at least a part of the electrolyte layer is provided with an adhesive layer for adhering the electrolyte layer to a current collector or an electrode mixture layer.

In the fourth aspect, the pressure-sensitive adhesive layer may have an electrolyte layer adhered to the current collector.

The present invention provides, as a fifth aspect, a secondary battery including the above battery member.

The present invention provides, as a sixth aspect, a method for manufacturing a battery member for a secondary battery, which comprises a step of bonding an electrode and an electrolyte layer of an electrolyte sheet via an adhesive layer.

In the seventh aspect of the present invention, a step of unwinding the electrolyte layer provided with the pressure-sensitive adhesive layer from the electrolyte sheet winding body and a pressure-sensitive adhesive layer of the unwound electrolyte layer and at least one of the positive electrode and the negative electrode are formed. Provided is a method for manufacturing a secondary battery, which comprises a step of obtaining a laminated body including a positive electrode, an electrolyte layer and a negative electrode in this order after bonding through the laminate, and winding the laminated body.

According to the present invention, it is possible to provide an electrolyte sheet capable of suitably laminating an electrolyte layer with an electrode, a battery member for a secondary battery and a secondary battery using the electrolyte sheet, and a method for producing these. it can.

It is a perspective view which shows the overall structure and the internal structure of the secondary battery which concerns on 1st Embodiment. It is a schematic cross-sectional view which shows the region of the winding start of the electrode group in the secondary battery shown in FIG. It is a schematic cross-sectional view which shows the modification of the electrode group in the secondary battery shown in FIG. (A) is a perspective view which shows the electrolyte sheet winding body which concerns on one Embodiment, and (b) is a schematic cross-sectional view which shows the electrolyte sheet of the electrolyte sheet winding body of (a). It is a schematic diagram which shows the manufacturing method of the secondary battery which concerns on 1st Embodiment. It is a schematic cross-sectional view which shows the modification of the electrolyte sheet. It is a perspective view which shows the modification of the electrolyte sheet winding body. It is a perspective view which shows the electrolyte sheet which cut out a part of the electrolyte sheet winding body shown in FIG. 7. It is a schematic cross-sectional view which shows the region of the winding start of the electrode group of the secondary battery which concerns on 2nd Embodiment. It is a schematic diagram which shows the manufacturing method of the secondary battery which concerns on 2nd Embodiment.

Hereinafter, embodiments of the present invention will be described with reference to the drawings as appropriate. However, the present invention is not limited to the following embodiments. In the following embodiments, the components (including steps and the like) are not essential unless otherwise specified. The sizes of the components in each figure are conceptual, and the relative size relationships between the components are not limited to those shown in each figure.

The numerical values and their ranges in the present specification do not limit the present invention. In the present specification, the numerical range indicated by using "~" indicates a range including the numerical values before and after "~" as the minimum value and the maximum value, respectively. In the numerical range described stepwise in the present specification, the upper limit value or the lower limit value described in one numerical range may be replaced with the upper limit value or the lower limit value described in another stepwise description. Further, in the numerical range described in the present specification, the upper limit value or the lower limit value of the numerical range may be replaced with the value shown in the examples.

FIG. 1 is a perspective view showing the overall configuration and internal structure of the secondary battery according to the first embodiment. As shown in FIG. 1, the secondary battery 1 includes a long positive electrode 2 and a negative electrode 3, and an electrode group 5 in which a long electrolyte layer 4 interposed between them is spirally wound. It is a 18650 type (cylindrical type) secondary battery including a cylindrical battery container 6 accommodating the electrode group 5 and having an open top surface, and a lid 7 closing the opening of the battery container 6. An insulating coating (not shown) is applied to the entire outer peripheral surface of the electrode group 5. The battery container 6 may be, for example, a nickel-plated steel container. The lid 7 is caulked and fixed to the upper part of the battery container 6 via, for example, an insulating resin gasket.

The positive electrode 2 and the negative electrode 3 are provided with a positive electrode current collecting tab and a negative electrode current collecting tab (not shown) so that the positive electrode 2 and the negative electrode 3 can be electrically connected to the outside of the secondary battery 1, respectively. One end of the positive electrode current collecting tab is bonded to the lower surface of the lid 7 of the secondary battery 1 by, for example, ultrasonic welding. One end of the negative electrode current collecting tab is joined to the inner bottom portion 6a of the battery container 6 by, for example, resistance welding. In one embodiment, the positive electrode current collector tab is made of aluminum and the negative electrode current collector tab is made of copper.

FIG. 2 is a schematic cross-sectional view showing a region at the beginning of winding of the electrode group 5 in the secondary battery 1 shown in FIG. As shown in FIG. 2, the electrode group 5A according to the present embodiment includes an elongated first electrolyte layer 4, a positive electrode 2, a second electrolyte layer 4, and a negative electrode 3 in this order. .. The positive electrode 2 includes a positive electrode current collector 8 and a positive electrode mixture layer 9 provided on both sides of the positive electrode current collector 8. The negative electrode 3 includes a negative electrode current collector 10 and negative electrode mixture layers 11 provided on both sides of the negative electrode current collector 10. Hereinafter, the first electrolyte layer 4 and the second electrolyte layer 4 may be collectively referred to as an electrolyte layer 4.

On the surface 4a of the electrolyte layer 4 on the positive electrode mixture layer 9 side, a plurality of pressure-sensitive adhesive layers 12 are provided at predetermined intervals in the longitudinal direction of the electrolyte layer 4, and each pressure-sensitive adhesive layer 12 (of the electrolyte layer 4). The pressure-sensitive adhesive layer 12 provided on the edge portion 4b) adheres the first electrolyte layer 4 and the second electrolyte layer 4 to the positive electrode mixture layer 9 (details of the pressure-sensitive adhesive layer 12 will be described later). ). The secondary battery 1 is provided on a surface of the positive electrode mixture layer 9 opposite to the positive electrode current collector 8 and the positive electrode mixture layer 9 provided on both sides of the positive electrode current collector 8. It can also be seen that the positive electrode member 13A having the first electrolyte layer 4 and the second electrolyte layer 4 provided is provided. In the positive electrode member 13A, at least a part of the first electrolyte layer 4 and the second electrolyte layer 4 is in contact with the positive electrode mixture layer 9 via the pressure-sensitive adhesive layer 12.

The positive electrode current collector 8 may be made of aluminum, stainless steel, titanium, or the like. The thickness of the positive electrode current collector 8 may be, for example, 10 μm or more and 100 μm or less.

In one embodiment, the positive electrode mixture layer 9 contains a positive electrode active material, a conductive agent, and a binder. The thickness of the positive electrode mixture layer 9 may be, for example, 5 μm or more and 100 μm or less.

The positive electrode active materials are LiCoO ₂ , LiNiO ₂ , LiMn ₂ O ₄ , LiMnO ₃ , LiMn ₂ O ₃ , LiMnO ₂ , Li ₄ Mn ₅ O ₁₂ , LiMn _2-a M ¹ _a O ₂ (where M ¹ = Co. , Ni, Fe, Cr, Zn, and Ta, which is one selected from the group, a = 0.01 to 0.2), Li ₂ Mn ₃ M ² O ₈ (where M ² = One selected from the group consisting of Fe, Co, Ni, Cu, and Zn.), Li _1-b M ³ _b Mn ₂ O ₄ (However, M ³ = Mg, B, Al, Fe, Co, It is one selected from the group consisting of Ni, Cr, Zn, and Ca, and b = 0.01 to 0.1.), LiFeO ₂ , Fe ₂ (SO ₄ ) ₃ , LiCo _1-d M ⁵ _d O ₂ (However, it is one selected from the group consisting of M ⁵ = Ni, Fe, and Mn, and d = 0.01 to 0.2), LiNi _1-e M ⁶ _e O ₂ (where M ⁵ = M ⁶ _e O ₂ ( However, it is one selected from the group consisting of M ⁶ = Mn, Fe, Co, Al, Ga, Ca, and Mg, and e = 0.01 to 0.2), Fe (MoO ₄ ) _3. , FeF ₃ , LiFePO ₄ , LiMnPO ₄ , and the like.

The conductive agent may be carbon black, graphite, carbon fiber, carbon nanotubes or the like. The binder is not limited as long as it does not decompose on the surface of the positive electrode 2, but is, for example, a polymer. The binder may be polyvinylidene fluoride, styrene / butadiene rubber, carboxyl / methylcellulose, cellulose acetate, cellulose such as ethylcellulose, fluororubber, ethylene / propylene rubber, polyacrylic acid, polyimide, polyamide or the like.

The negative electrode current collector 10 may be made of copper, stainless steel, titanium, nickel, or the like. The thickness of the negative electrode current collector 10 may be, for example, 10 μm or more and 100 μm or less.

In one embodiment, the negative electrode mixture layer 11 contains a negative electrode active material, a conductive agent, and a binder. The thickness of the negative electrode mixture layer 11 may be, for example, 10 μm or more and 50 μm or less.

The negative electrode active material may be natural graphite coated with amorphous carbon (theoretical capacity: 372 Ah / kg), and may be silicon, tin, or a compound containing these elements (oxide, nitride, alloy with other metals). ) May be.

The binder and the conductive agent may be the same as the binder and the conductive agent in the positive electrode mixture layer 9 described above.

The electrolyte layer 4 is made of an electrolyte composition. The compositions of the first electrolyte layer 4 and the second electrolyte layer 4 may be the same or different, and are preferably the same. In one embodiment, the electrolyte composition comprises one or more types of polyma, oxide particles, and at least one electrolyte salt selected from the group consisting of lithium salt, sodium salt, calcium salt, and magnesium salt. , Solvent and. The thickness of the electrolyte layer 4 may be 5 μm or more and 100 μm or less.

Among the structural units (monomers) that compose one or more types of polymers, a first structural unit (monomer unit) selected from the group consisting of ethylene tetrafluoride and vinylidene fluoride, and hexafluoropropylene. , Acrylic acid, maleic acid, ethyl methacrylate, and a second structural unit (monomer unit) selected from the group consisting of methyl methacrylate.

The first structural unit and the second structural unit may be contained in one kind of polymer to form a copolymer, or may be contained in different polymers and have a first structural unit. And a second polymer having a second structural unit may constitute at least two kinds of polymers.

Examples of the combination of the first polymer and the second polymer include polyvinylidene fluoride and polyacrylic acid, ethylene tetrafluoride and polymethyl methacrylate, vinylidene fluoride and polymethyl methacrylate, and the like.

The content of the polymer may be 10% by mass or more and 40% by mass or less based on the total amount of the electrolyte composition.

Oxide particles are, for example, inorganic oxide particles. The inorganic oxide is, for example, an inorganic oxide containing Li, Mg, Al, Si, Ca, Ti, Zr, La, Na, K, Ba, Sr, V, Nb, B, Ge and the like as constituent elements. Good. The oxide particles are preferably at least one selected from the group consisting of SiO ₂ , Al ₂ O ₃ , AlOOH, MgO, CaO, ZrO ₂ , TiO ₂ , Li ₇ La ₃ Zr ₂ O ₁₂ , and BaTIO ₃ . It is a particle. The average particle size of the oxide particles is, for example, 0.05 μm or more and 6 μm or less. The content of the oxide particles may be 10% by mass or more and 40% by mass or less based on the total amount of the electrolyte composition.

The lithium salt, which is an electrolyte salt, specifically includes lithium bis (trifluoromethanesulfonyl) imide (LiTFSI), lithium bis (fluorosulfonyl) imide (LiFSI), lithium trifluoroacetate, lithium borofluoride, and phosphorus hexafluorophosphate. It may be lithium acid or the like, and it is possible to use a known lithium salt used in a lithium secondary battery.

The sodium salt which is an electrolyte salt may be NaClO ₄ , NaBF ₄ , NaPF ₆ , sodium bis (trifluoromethanesulfonyl) imide (NaTFSI), sodium bis (fluorosulfonyl) imide (NaFSI) and the like, and the magnesium salt may be Mg. (ClO ₄ ) ₂ , Mg (TFSI) ₂ , magnesium dibutyldiphenyl (Mg (BPh ₂ Bu ₂ ) ₂ ), magnesium tributylphenyl (Mg (BPhBu ₃ ) ₂ ), Mg (BH ₄ ) _2, etc. may be used. The calcium salt may be Ca (ClO ₄ ) ₂ , Ca (BF _{4) 2} , Ca (TFSI) _2, or the like.

The content of the electrolyte salt may be 10% by mass or more and 60% by mass or less based on the total amount of the electrolyte composition.

The solvent may be grime represented by the following formula (1).
R ¹ O- (CH ₂ CH ₂ O) _n- R ² (1)
In the formula (1), R ¹ and R ² independently represent an alkyl group having 4 or less carbon atoms or a fluoroalkyl group having 4 or less carbon atoms, and n represents an integer of 1 to 6. R ¹ and R ² are independent of each other, preferably one of CH ₃ and C ₂ H ₅ .

Specifically, the grime is mono-grime (n = 1), jig-grime (n = 2), tri-grime (n = 3), tetra-grime (n = 4), pentag-grime (n = 5), hexa-grime (n = 5). 6) may be.

When the electrolyte composition contains grime as a solvent, part or all of the grime may form a complex with the electrolyte salt.

The solvent may be an ionic liquid. The ionic liquid may be, for example, at least one ionic liquid selected from the group consisting of an imidazolium-based ionic liquid and a pyridinium-based ionic liquid.

［式（２）中、Ｒ^３〜Ｒ^７は、それぞれ独立に、炭素数が１〜２０のアルキル基、Ｒ−Ｏ−（ＣＨ_２）_ｍ−で表されるアルコキシアルキル基（Ｒはメチル基又はエチル基を表し、ｍは１〜４の整数を表す）、又は水素原子を表す。Ｒ^３〜Ｒ^７で表されるアルキル基の炭素数は、好ましくは１〜２０、より好ましくは１〜１０、更に好ましくは１〜５である。］The imidazolium-based ionic liquid is a compound containing an imidazolium cation represented by the following general formula (2).

[In formula (2), R ^{3 to} R ⁷ are independently alkyl groups having 1 to 20 carbon atoms and alkoxyalkyl groups represented by RO-O- (CH ₂ ) _m- (R is a methyl group). Or represents an ethyl group, m represents an integer of 1 to 4), or represents a hydrogen atom. The alkyl group represented by R ^{3 to} R ⁷ has preferably 1 to 20 carbon atoms, more preferably 1 to 10 carbon atoms, and further preferably 1 to 5 carbon atoms. ]

［式（３）中、Ｒ^８〜Ｒ^１２は、それぞれ独立に、炭素数が１〜２０のアルキル基、Ｒ−Ｏ−（ＣＨ_２）_ｍ−で表されるアルコキシアルキル基（Ｒはメチル基又はエチル基を表し、ｍは１〜４の整数を表す）、又は水素原子を表す。Ｒ^８〜Ｒ^１２で表されるアルキル基の炭素数は、好ましくは１〜２０、より好ましくは１〜１０、更に好ましくは１〜５である。］The pyridinium-based ionic liquid is a compound containing a pyridium cation represented by the following general formula (3).

[In the formula (3), R ^{8 to} R ¹² are independently alkyl groups having 1 to 20 carbon atoms and alkoxyalkyl groups represented by RO-O- (CH ₂ ) _m- (R is a methyl group). Or an ethyl group, m represents an integer of 1 to 4), or a hydrogen atom. The alkyl group represented by R ^{8 to} R ¹² has preferably 1 to 20 carbon atoms, more preferably 1 to 10 carbon atoms, and further preferably 1 to 5 carbon atoms. ]

Anion component of the ionic liquid is not particularly ^{limited, Cl -, Br -, I} - halogen anions _{^{such, BF 4 -, N (SO}} 2 F) 2 - or the like of the inorganic _{anion, B} (C _{6 H} 5) _{^{4 -, CH 3 SO 3 -}} , CF 3 SO 3 -, N (C 4 F 9 SO 2) 2 -, N (SO 2 CF 3) 2 -, N (SO 2 CF 2 CF 3) 2 - , etc. It may be an organic anion or the like. Anion component of the ionic liquid, _{^{preferably, B (C 6 H 5)}} 4 -, CH 3 SO 3 -, N (C 4 F 9 SO 2) 2 -, CF 3 SO 3 -, N (SO 2 F) _{^{2 -, N (SO 2 CF}} 3) 2 - and _{N (SO 2 CF 2 CF 3} ) 2 - is at least one selected from the group consisting of. The anionic component of the ionic liquid is more preferably N (C ₄ F ₉ SO ₂ ) ₂ ⁻ , CF ₃ SO from the viewpoint of further improving the ionic conductivity and the charge / discharge characteristics with a relatively low viscosity. _{^{3 -, N (SO 2 F}} ) 2 -, N (SO 2 CF 3) 2 -, and _{N (SO 2 CF 2 CF 3} ) 2 - is at least one selected from the group consisting of, more preferably N _{(SO 2 F)} 2 ^- a.

The content of the solvent may be 10% by mass or more and 60% by mass or less based on the total amount of the electrolyte composition. The total content of the electrolyte salt and the solvent may be 10% by mass or more and 80% by mass or less based on the total amount of the electrolyte composition.

In one embodiment, the pressure-sensitive adhesive layer 12 may have a three-layer structure in which pressure-sensitive adhesives are provided on both sides of the support film. As a result, the strength of the pressure-sensitive adhesive layer 12 is increased, and handling can be facilitated. The support film may be, for example, a polyethylene terephthalate film having a thickness of about 10 μm. In another embodiment, the pressure-sensitive adhesive layer 12 may have a single-layer structure composed of only the pressure-sensitive adhesive. As a result, the thickness of the pressure-sensitive adhesive layer 12 is reduced.

The pressure-sensitive adhesive forming the pressure-sensitive adhesive layer 12 includes an acrylic pressure-sensitive adhesive containing an acrylic resin or a methacrylic resin, a silicone-based pressure-sensitive adhesive containing a silicone resin, a urethane-based pressure-sensitive adhesive containing a urethane resin, and an ether-based pressure-sensitive adhesive containing a polyvinyl ether. It may be a rubber-based adhesive containing styrene / butadiene rubber. The pressure-sensitive adhesive layer 12 is preferably an acrylic pressure-sensitive adhesive from the viewpoint that it is not easily dissolved or decomposed by the solvent contained in the electrolyte layer 4.

The electrode group 5 in the secondary battery 1 may take a modified example. FIG. 3 is a schematic cross-sectional view showing a modified example of the electrode group 5 in the secondary battery 1 shown in FIG. As shown in FIG. 3, in the electrode group 5B, the pressure-sensitive adhesive layer 12 provided on the edge portion 4b of the electrolyte layer 4 may have the electrolyte layer 4 adhered to the positive electrode current collector 8. In the electrode group 5B, the edge portion 8a of the positive electrode current collector 8 protrudes outward from the edge portion 9a of the positive electrode mixture layer 9 when viewed from the stacking direction. Therefore, the electrolyte layer 4 is adhered to the positive electrode current collector 8 via the pressure-sensitive adhesive layer 12 formed on the edge portion 4b of the electrolyte layer 4. In this secondary battery, since the portion of the positive electrode mixture layer 9 covered by the pressure-sensitive adhesive layer 12 is reduced, the capacity loss of the positive electrode 2 can be further reduced.

Subsequently, the method for manufacturing the secondary battery 1 described above will be described. The method for manufacturing the secondary battery 1 includes a first step of forming the positive electrode mixture layer 9 on the positive electrode current collector 8 to obtain the positive electrode 2 and forming the negative electrode mixture layer 11 on the negative electrode current collector 10. A third step of obtaining the negative electrode 3 and a third step of obtaining a laminate having the first electrolyte layer 4, the positive electrode 2, the second electrolyte layer 4 and the negative electrode 3 in this order, and winding the laminate. It has a process.

In the first step, for the positive electrode 2, for example, the material used for the positive electrode mixture layer 9 is dispersed in a dispersion medium using a kneader, a disperser, or the like to obtain a slurry-like positive electrode mixture, and then the positive electrode mixture is obtained. The agent is applied onto the positive electrode current collector 8 by a doctor blade method, a dipping method, a spray method, or the like, and then the dispersion medium is volatilized. After volatilizing the dispersion medium, a compression molding step by a roll press may be provided, if necessary. The positive electrode mixture layer 9 may be formed as a multilayer structure positive electrode mixture layer by performing the above-mentioned steps from application of the positive electrode mixture to volatilization of the dispersion medium a plurality of times. The positive electrode 2 may be stored as a winding body (positive electrode winding body) until the secondary battery 1 is manufactured.

The dispersion medium used in the first step may be water, 1-methyl-2-pyrrolidone (NMP), or the like.

In the second step, the method of forming the negative electrode mixture layer 11 on the negative electrode current collector 10 may be the same method as in the first step described above. The negative electrode 3 may be stored as a winding body (negative electrode winding body) until the secondary battery 1 is manufactured.

In the third step, first, the positive electrode 2 and the electrolyte layer 4 are bonded together. At this time, in one embodiment, the electrolyte layer 4 is used by being unwound from the electrolyte sheet winder. FIG. 4A is a perspective view showing the electrolyte sheet wound body according to the embodiment, and FIG. 4B is a schematic cross-sectional view taken along the line IVb-IVb of FIG. 4A. As shown in FIG. 4A, the electrolyte sheet winding body 15A according to the embodiment includes a winding core 16 and an electrolyte sheet 17A having an electrolyte layer 4 wound around the winding core 16. As shown in FIG. 4B, the electrolyte sheet 17A has a long base material 18, a long base material 4 provided on the main surface 18a of the base material 18, and a group of the electrolyte layer 4. A plurality of pressure-sensitive adhesive layers 12 provided on the surface 4c opposite to the material 18 are provided.

Each pressure-sensitive adhesive layer 12 has an elongated shape (elongated rectangular shape) extending in the lateral direction of the electrolyte layer 4. The width (length of the short side) W ₁₂ of each pressure-sensitive adhesive layer 12 may be, for example, 1 mm or more, or 50 mm or less. The length (length of the long side) L ₁₂ of each pressure-sensitive adhesive layer 12 is preferably the same as the length of the electrolyte layer 4 in the lateral direction, for example, 1 mm or more, and the lateral direction. It may be less than or equal to the length of. If the adhesive strength is sufficiently strong so that the adhesive layer 12 does not peel off even if tension is applied in the longitudinal direction of the electrolyte layer 4 during battery assembly, the length L ₁₂ of the adhesive layer ₁₂ is short of the electrolyte layer 4. It may be smaller than the hand length. The pressure-sensitive adhesive layer may be divided into a plurality of spots (dots) in the lateral direction of the electrolyte layer 4, and may have a shape other than a rectangular shape.

The thickness _{T 12} of the adhesive layer 12 is preferably 5μm or more, more preferably 10μm or more, more preferably may be at 30μm or more, and preferably 100μm or less, more preferably 50μm or less, more preferably 30μm It may be: Since the thickness T ₁₂ of the pressure-sensitive adhesive layer is 5 μm or more, the amount of displacement due to compression of the pressure-sensitive adhesive layer 12 does not become too small when the pressure-sensitive adhesive layer 12 is adhered to the electrolyte layer 4. Therefore, the pressure-sensitive adhesive layer 12 The adhesive can bite into the unevenness of the surface of the electrolyte layer 4, and sufficient adhesive strength can be obtained. When the thickness T ₁₂ of the pressure-sensitive adhesive layer is 100 μm or less, a large step is not generated in the vicinity of the pressure-sensitive adhesive layer 12, so that the positive electrode 2 and the negative electrode 3 are sufficiently adhered to each other, and the battery performance can be improved. ..

A plurality of pressure-sensitive adhesive layer 12 is provided at a predetermined interval G ₁₂ in the longitudinal direction of the electrolyte layer 4. Adhesive layer 12 spacing _{G 12} between, for example, may be at 10mm or more, may be at less than 100mm.

The base material 18 is not limited as long as it has heat resistance that can withstand heating when the dispersion medium is volatilized, does not react with the electrolyte composition, and does not swell due to the electrolyte composition, but is not limited, for example, in the form of a film. Resin. Specifically, the base material 18 may be a film made of a resin (general-purpose engineer plastic) such as polyethylene terephthalate, polytetrafluoroethylene, polyimide, polyethersulfone, and polyetherketone.

The base material 18 is required to withstand the treatment temperature at which the dispersion medium is vaporized in the process of producing the electrolyte layer 4. The lower of the softening point (temperature at which plastic deformation begins) or the melting point of the base material 18 is set as the heat resistant temperature, and the temperature is preferably 50 ° C. or higher from the viewpoint of compatibility with the solvent used for the electrolyte layer 4. It is more preferably 100 ° C. or higher, further preferably 150 ° C. or higher, and for example, 400 ° C. or lower. If a base material having the above heat resistant temperature is used, the dispersion medium used for forming the electrolyte layer 4 on the base material 18 can be preferably used.

The thickness of the base material 18 is preferably as thin as possible while maintaining strength that can withstand the tensile force of the coating apparatus. The thickness of the base material 18 is preferably 5 μm or more, more preferably 10 μm or more, from the viewpoint of ensuring the strength when the electrolyte composition is applied to the base material 18 while reducing the volume of the entire electrolyte sheet 17A. It is more preferably 25 μm or more, preferably 100 μm or less, more preferably 50 μm or less, still more preferably 40 μm or less.

In the method of manufacturing the electrolyte sheet wound body 15A, for example, first, the electrolyte layer 4 is provided on the main surface 18a of the elongated base material 18. Specifically, the electrolyte layer 4 is produced by dispersing the material used for the electrolyte layer 4 in a dispersion medium to obtain a slurry, applying the slurry on the base material 18, and then volatilizing the dispersion medium. .. The dispersion medium is preferably water, NMP, toluene or the like.

Then, on the opposite side of the surface 4c and the base material 18 of the electrolyte layer 4, provided with a plurality of pressure-sensitive adhesive layer 12 at predetermined intervals G ₁₂ in the longitudinal direction of the electrolyte layer 4. For the pressure-sensitive adhesive layer 12, for example, a film-like pressure-sensitive adhesive is pressure-bonded, or the pressure-sensitive adhesive layer 12 produced on the release film is pressure-bonded to the electrolyte layer 4 to peel off the release film to transfer the pressure-sensitive adhesive layer 12. It can be provided by applying a liquid pressure-sensitive adhesive to the electrolyte layer 4. As a result, the electrolyte sheet 17A is obtained. By winding the obtained electrolyte sheet 17A around the winding core 16, the electrolyte sheet winding body 15A can be obtained.

In the electrolyte sheet 17A shown in FIG. 4, the pressure-sensitive adhesive layer 12 is provided so as to cover all the edges (short sides) of one end of the electrolyte layer 4, but the pressure-sensitive adhesive layer 12 is the edge portion of the electrolyte layer 4. It may be provided apart from (short side and long side).

In the electrolyte sheet 17A shown in FIG. 4, a plurality of pressure-sensitive adhesive layers 12 are formed, but the pressure-sensitive adhesive layer 12 may be formed only at one end of the electrolyte layer 4 at the start of winding. In this case, the electrolyte layer 4 can be wound together with the positive electrode 2 and the negative electrode 3 to be suitably laminated, and the area of the pressure-sensitive adhesive layer 12 is reduced, which is more preferable.

In the third step, the above-mentioned electrolyte sheet winder 15A is used. FIG. 5 is a schematic view showing a third step of the method for manufacturing the secondary battery 1. In the third step, first, the positive electrode winding body 19, the negative electrode winding body 20, and the two electrolyte sheet winding bodies 15A are prepared, respectively. Next, the electrolyte sheet 17A is unwound from each of the two electrolyte sheet winding bodies 15A, and the electrolyte layer 4 obtained by peeling the base material 18 from each of the electrolyte sheet 17A is wound from the positive electrode winding body 19. It is attached to both sides (positive electrode mixture layer 9) of the positive electrode 2 that has been put out. At this time, the positive electrode mixture layer 9 and the electrolyte layer 4 are bonded to each other via the pressure-sensitive adhesive layer 12. As a result, the positive electrode current collector 8 and the positive electrode mixture layers 9 provided on both sides of the positive electrode current collector 8 are provided on the surfaces of the positive electrode mixture layers 9 on opposite sides of the positive electrode current collector 8. A secondary battery battery member (positive electrode member) 13A is formed which includes the electrolyte layer 4 and a part of the electrolyte layer 4 is adhered to the positive electrode mixture layer 9 via the pressure-sensitive adhesive layer 12. Further, the negative electrode 3 is unwound from the negative electrode winding body 20, and the positive electrode member 13A and the negative electrode 3 are laminated so that the electrolyte layer 4 of the obtained positive electrode member 13A and the negative electrode mixture layer 11 of the negative electrode 3 are in contact with each other. While winding around the winding shaft 21, the electrode group 5A (5) can be obtained.

According to the manufacturing method of the present embodiment, since the positive electrode 2 and the electrolyte layer 4 are bonded to each other via the pressure-sensitive adhesive layer 12, the positive electrode 2 and the electrolyte layer 4 can be suitably laminated. Wrinkles or wrinkles are particularly likely to occur at the end of the region where the electrolyte layer 4 and the positive electrode 2 begin to be laminated, and once they occur at the end, the same defect may occur in the entire electrode group 5. In the production method of the present embodiment, since the pressure-sensitive adhesive layer 12 is provided at the end of the electrolyte layer 4, wrinkles or wrinkles at the ends of the positive electrode 2 and the electrolyte layer 4 can be effectively suppressed.

The electrolyte sheet 17A wound around the electrolyte sheet winder 15A used in the third step can take various deformation modes. FIG. 6 is a schematic cross-sectional view of the electrolyte sheet according to the modified example. As a first modification, the electrolyte sheet 17B shown in FIG. 6A further includes a protective layer 22 provided on the electrolyte layer 4 and the pressure-sensitive adhesive layer 12 (opposite to the base material 18 of the electrolyte layer 4). ing. When the protective layer 22 is not provided, when the electrolyte sheet is wound around the winding core to manufacture the electrolyte sheet wound body, the base material 18 adheres to the surface (back surface of the base material) 18b opposite to the electrolyte layer 4. The agent layer may adhere to each other, making it difficult to smoothly unwind the electrolyte sheet in the third step. However, since the protective layer 22 is provided, the adhesion of the pressure-sensitive adhesive layer 12 to the back surface 18b of the base material is suppressed, the electrolyte sheet wound body can be suitably manufactured, and the electrolyte sheet wound body can be used as an electrolyte sheet. When unwinding 17B, it becomes easy to unwind. When the protective layer 22 is provided, in the third step in the manufacture of the secondary battery, the protective layer 22 is peeled off in addition to the base material 18 before the positive electrode 2 and the electrolyte layer 4 are bonded to each other. To.

The protective layer 22 may be any one that can be easily peeled off from the electrolyte layer 4 and the pressure-sensitive adhesive layer 12, and is preferably a non-polar resin film such as polyethylene, polypropylene, or polytetrafluoroethylene. When a non-polar resin film is used, the electrolyte layer 4, the adhesive layer 12, and the protective layer 22 do not stick to each other, and the protective layer 22 can be easily peeled off.

The thickness of the protective layer 22 is preferably 5 μm or more, more preferably 10 μm, and preferably 100 μm or less, from the viewpoint of ensuring the strength while reducing the volume of the entire electrolyte sheet 17B. It is preferably 50 μm or less, and more preferably 30 μm or less.

As a second modification, the electrolyte sheet 17C shown in FIG. 6B includes a release layer 23 on the back surface 18b of the base material 18. By providing the release layer 23, it is possible to prevent the back surface 18b of the base material from adhering to the pressure-sensitive adhesive layer 12 when the electrolyte sheet wound body is produced, even if the protective layer is not provided. .. In one embodiment, the release layer 23 may be a layer formed by a mold release treatment using a polymer such as polyethylene, polypropylene, polystyrene, or polyethylene terephthalate, and containing such a polymer.

The thickness of the release layer 23 is preferably 5 μm or more, more preferably 10 μm or more, further preferably 30 μm or more, and preferably 200 μm or less, more preferably 100 μm or less, and further. It is preferably 50 μm or less.

As a third modification, in the electrolyte sheet 17D shown in FIG. 6C, the pressure-sensitive adhesive layer 12 provided on the edge portion 4b of the electrolyte layer 4 is directed from the central portion of the electrolyte layer 4 toward the edge portion 4b. It has a shoulder-like shape (tapered shape) that gradually becomes thinner. That is, the thickness of the edge portion 4b of the electrolyte layer 4 is thinner than that of the central portion of the electrolyte layer 4.

FIG. 7 is a perspective view showing another modified example of the electrolyte sheet wound body. The electrolyte sheet winding body 15B has a long base material 18, an electrolyte layer 4 provided on the main surface of the base material 18, and a longitudinal direction on the surface of the electrolyte layer 4 opposite to the base material 18. The pressure-sensitive adhesive layer 32 is provided with a plurality of pressure-sensitive adhesive layers 32 provided at predetermined intervals G ₃₂ , and the pressure-sensitive adhesive layer 32 has an elongated shape extending along the long side of the electrolyte sheet 17E. As a further modification of the electrolyte sheet 17E, the above-mentioned protective layer or release layer can be provided.

Number adhesive layer 32 between the interval _{G 32} is, for example, may be at 1mm or more, but may be at 1000mm or less, more larger adhesive layer 32 spacing _{G 32} between is provided with a pressure-sensitive adhesive layer 32 Is more preferable because it can reduce the amount of In the electrolyte sheet winding body 15B shown in FIG. 7, the distance G ₃₂ between the pressure-sensitive adhesive layers 32 may be zero, that is, all the pressure-sensitive adhesive layers 32 may be continuously connected. The width (length of the short side) W ₃₂ of each pressure-sensitive adhesive layer 32 may be, for example, 1 mm or more, or 5 mm or less. The length (length of the long side) L ₃₂ of each pressure-sensitive adhesive layer 32 may be, for example, 1 mm or more, or 1000 mm or less.

In the electrolyte sheet 17E, the pressure-sensitive adhesive layer 32 is cut between the pressure-sensitive adhesive layers 32 along the lateral direction of the electrolyte sheet 17E so that the pressure-sensitive adhesive layer 32 is formed at one end edge of the electrolyte layer 4 as shown in FIG. It is possible to obtain an individual piece-shaped electrolyte sheet 17F provided with. As a result, the electrolyte layer 4 and the electrode can be suitably laminated, particularly in the production of a secondary battery other than the winding type battery such as a laminated type battery and a coin type battery. The individual piece-shaped electrolyte sheet 17F shown in FIG. 8 is cut out from the electrolyte sheet 17E shown in FIG. 7, and the electrolyte layer 4 and the adhesive layer 12 are formed on the main surface of the individual piece-shaped base material 18 from the beginning. And may be provided to manufacture the individual piece-shaped electrolyte sheet 17F.

In the electrolyte sheet 17E shown in FIG. 7, the pressure-sensitive adhesive layer 32 is provided so as to cover the edge portion (long side) of the electrolyte layer 4, but the pressure-sensitive adhesive layer 32 is provided at the edge portion (long side) of the electrolyte layer 4. It may be provided apart from. Similarly, in the electrolyte sheet 17F shown in FIG. 8, the pressure-sensitive adhesive layer 32 is provided so as to cover all the edges (short sides) of one end of the electrolyte layer 4, but the pressure-sensitive adhesive layer 32 is the electrolyte layer 4. It may be provided apart from the edge portion (short side and long side) of the.

[Second Embodiment]
Next, the secondary battery according to the second embodiment will be described. Hereinafter, the configurations corresponding to the secondary battery according to the first embodiment are designated by the same reference numerals, and redundant description will be omitted.

FIG. 9 is a schematic cross-sectional view showing a region at the beginning of winding of the electrode group in the secondary battery according to the second embodiment. As shown in FIG. 9, in the electrode group 5C according to the second embodiment, one positive electrode mixture layer 9 and the first electrolyte layer 4 in the positive electrode 2 are adhered to each other via the pressure-sensitive adhesive layer 12. The negative electrode mixture layer 11 and the second electrolyte layer 4 of the negative electrode 3 are adhered to each other via the pressure-sensitive adhesive layer 12. That is, the electrode group 5C according to the present embodiment includes a positive electrode 2 having a positive electrode mixture layer 9 provided on both sides of the positive electrode current collector 8 and the positive electrode current collector 8, a first electrolyte layer 4, and a negative electrode collection. A negative electrode 3 having a negative electrode mixture layer 11 provided on both sides of the electric body 10 and the negative electrode current collector 10 and a second electrolyte layer 4 are provided in this order, and the positive electrode 2 and the first electrolyte layer 4 are provided. A pressure-sensitive adhesive layer 12 is provided between the two and between the negative electrode 3 and the second electrolyte layer 4, respectively.

It is considered that this secondary battery includes a positive electrode 2 and a battery member (positive electrode member) 13C for a secondary battery having an electrolyte layer 4 bonded to one surface of the positive electrode 2 via an adhesive layer 12. Further, it is considered that the battery member (negative electrode member) 13D for a secondary battery having the negative electrode 3 and the electrolyte layer 4 bonded to one surface of the negative electrode 3 via the adhesive layer 12 is provided. You can also.

FIG. 10 is a schematic view showing a method of manufacturing a secondary battery according to a second embodiment. The method for manufacturing the secondary battery is the same as the method for manufacturing the secondary battery according to the first embodiment, that is, the first step and the second step, the positive electrode 2 and the electrolyte layer 4, and the negative electrode 3 and the electrolyte layer. 4 and 4 are bonded to each other via the pressure-sensitive adhesive layer 12, and then a laminate having a positive electrode 2, a first electrolyte layer 4, a negative electrode 3 and a second electrolyte layer 4 in this order is obtained, and the laminate is provided. It is provided with a third step of winding the.

In the third step according to the present embodiment, the electrolyte sheet 17A is unwound from one of the electrolyte sheet winders 15A, and the electrolyte layer 4 obtained by peeling the base material 18 from the electrolyte sheet 17A is wound with a positive electrode. It is bonded onto one positive electrode mixture layer 9 of the positive electrode 2 unwound from the body 19. At this time, the positive electrode mixture layer 9 and the electrolyte layer 4 of the positive electrode 2 are bonded to each other via the pressure-sensitive adhesive layer 12. As a result, the positive electrode current collector 8 and the positive electrode mixture layer 9 provided on both sides of the positive electrode current collector 8 are provided on one main surface of the positive electrode mixture layer 9 via the pressure-sensitive adhesive layer 12. A positive electrode member 13C including the electrolyte layer 4 is obtained.

On the other hand, the electrolyte sheet 17A is unwound from the other side of the electrolyte sheet winding body 15A, and the electrolyte layer 4 obtained by peeling the base material 18 from the electrolyte sheet 17A is unwound from the negative electrode winding body 20. It is bonded onto one of the negative electrode mixture layers 11 in 3. At this time, the negative electrode mixture layer 11 and the electrolyte layer 4 of the negative electrode 3 are bonded to each other via the pressure-sensitive adhesive layer 12. As a result, the negative electrode current collector 10 and the negative electrode mixture layer 11 provided on both sides of the negative electrode current collector 10 are provided on one main surface of the negative electrode mixture layer 11 via the pressure-sensitive adhesive layer 12. A negative electrode member 13D including the electrolyte layer 4 is obtained. Then, the positive electrode member 13C and the negative electrode member 13D are laminated and wound around the winding shaft 21 so that the first electrolyte layer 4 of the obtained positive electrode member 13C and the negative electrode 3 of the negative electrode member 13D are in contact with each other. The electrode group 5C is obtained.

Also in the manufacturing method of the present embodiment, the positive electrode 2 and the electrolyte layer 4, and the negative electrode 3 and the electrolyte layer 4 are bonded to each other via the adhesive layer 12, so that the positive electrode 2 and the electrolyte layer 4 and the negative electrode are bonded together. 3 and the electrolyte layer 4 can be suitably laminated.

In yet another embodiment of the secondary battery, the electrode group is bipolar with a positive electrode mixture layer on one surface of the bipolar electrode current collector and a negative electrode mixture layer on the opposite surface to the positive electrode mixture layer. Further electrodes may be provided. The secondary battery in this case includes, for example, a first electrolyte layer, a positive electrode, a second electrolyte layer, a bipolar electrode, a third electrolyte layer, and a negative electrode in this order. The bipolar electrode is arranged with the positive electrode mixture layer facing the negative electrode side and the negative electrode mixture layer facing the positive electrode side. In this secondary battery, the positive electrode side surface of the first electrolyte layer, the positive electrode side or bipolar electrode side surface of the second electrolyte layer, and the bipolar electrode side surface or negative electrode side surface of the third electrolyte layer. May be provided with the above-mentioned pressure-sensitive adhesive layer. Also in this secondary battery, since the positive electrode, the bipolar electrode, and the negative electrode and the electrolyte layer provided between them can be bonded to each other via the pressure-sensitive adhesive layer at the time of manufacturing, each electrode and the electrolyte layer can be bonded to each other. It can be suitably laminated.

1 ... Secondary battery, 2 ... Positive electrode, 3 ... Negative electrode, 4 ... Electrolyte layer, 8 ... Positive electrode current collector, 9 ... Positive electrode mixture layer, 10 ... Negative electrode current collector, 11 ... Negative electrode mixture layer, 12, 32 ... Adhesive layer, 13A, 13B, 13C, 13D ... Battery member for secondary battery, 15A, 15B ... Electrolyte sheet winder, 16 ... Core, 17A, 17B, 17C, 17D, 17E, 17F ... Electrolyte sheet, 18 ... base material, 18a ... main surface of base material, 22 ... protective layer, 23 ... release layer.

Claims (19)

With the electrolyte layer,
An electrolyte sheet comprising an adhesive layer provided on at least a part of the main surface of the electrolyte layer. Further equipped with a long base material,
The electrolyte sheet according to claim 1, wherein the electrolyte layer is a long-shaped electrolyte layer provided on the main surface of the base material. The electrolyte sheet according to claim 2, wherein a plurality of the pressure-sensitive adhesive layers are provided on the main surface of the electrolyte layer on the side opposite to the base material at predetermined intervals in the longitudinal direction of the electrolyte layer. The electrolyte sheet according to claim 3, wherein each of the pressure-sensitive adhesive layers has an elongated shape extending along the lateral direction of the electrolyte layer. The electrolyte sheet according to claim 3, wherein each of the pressure-sensitive adhesive layers has an elongated shape extending along the longitudinal direction of the electrolyte layer. The electrolyte sheet according to any one of claims 2 to 5, further comprising a protective layer provided on the electrolyte layer and the pressure-sensitive adhesive layer. The electrolyte sheet according to any one of claims 2 to 5, further comprising a release layer on a surface of the base material opposite to the electrolyte layer. The electrolyte sheet according to any one of claims 1 to 7, wherein the pressure-sensitive adhesive layer is provided at one end of the electrolyte layer. The electrolyte sheet according to claim 8, wherein the pressure-sensitive adhesive layer is provided so as to cover all the edges of the one end portion of the electrolyte layer. The electrolyte sheet according to claim 9, wherein the thickness of the electrolyte layer in the region where the pressure-sensitive adhesive layer is provided becomes thinner toward the edge portion. The electrolyte layer is
With one or more polymers,
With oxide particles
At least one electrolyte salt selected from the group consisting of lithium salt, sodium salt, calcium salt, and magnesium salt, and
The electrolyte sheet according to any one of claims 1 to 10, which contains a solvent. The adhesive layer according to any one of claims 1 to 11, wherein the pressure-sensitive adhesive layer contains at least one selected from the group consisting of acrylic resin, methacrylic resin, silicone resin, urethane resin, polyvinyl ether, and styrene-butadiene rubber. Electrolyte sheet. With the core
An electrolyte sheet winding body comprising the electrolyte sheet according to any one of claims 1 to 12 wound around the winding core. The process of providing a long electrolyte layer on the main surface of a long base material, and
A method for producing an electrolyte sheet, comprising a step of providing a plurality of pressure-sensitive adhesive layers at predetermined intervals in the longitudinal direction of the electrolyte layer on a surface of the electrolyte layer opposite to the base material. A current collector, an electrode mixture layer provided on the main surface of the current collector, and an electrolyte layer provided on the surface of the electrode mixture layer opposite to the current collector are provided.
A battery member for a secondary battery, wherein at least a part of the electrolyte layer is provided with an adhesive layer for adhering the electrolyte layer to the current collector or the electrode mixture layer. The battery member according to claim 15, wherein the pressure-sensitive adhesive layer adheres the electrolyte layer to the current collector. A secondary battery comprising the battery member according to claim 15 or 16. A method for manufacturing a battery member for a secondary battery, comprising a step of bonding an electrode and the electrolyte layer of the electrolyte sheet according to any one of claims 1 to 12 via the pressure-sensitive adhesive layer. A step of unwinding the electrolyte layer provided with the pressure-sensitive adhesive layer from the electrolyte sheet winder according to claim 13.
After laminating the unwound electrolyte layer and at least one of the positive electrode and the negative electrode via the adhesive layer, a laminate having the positive electrode, the electrolyte layer and the negative electrode in this order is obtained, and the laminate is provided. A method for manufacturing a secondary battery, which comprises a step of winding the battery.

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