WO2019008546A1

WO2019008546A1 - Laminated electrode body manufacturing method, and energy storage element manufacturing method

Info

Publication number: WO2019008546A1
Application number: PCT/IB2018/054992
Authority: WO
Original assignee: リチウム・エネルギー・アンド・パワー・GmbH & Co. KG
Priority date: 2017-07-06
Filing date: 2018-07-06
Publication date: 2019-01-10
Also published as: JP2019016494A

Abstract

[Problem] The present invention addresses the problem of providing a laminated electrode body manufacturing method with which a laminated electrode body having a large energy density can be efficiently manufactured. [Solution] A laminated electrode body manufacturing method according to one embodiment of the present invention comprises: disposing one positive electrode plate between two separators, each of which has an adhesive layer on both surfaces thereof, and disposing one negative electrode plate on one of the two separators; heating and pressing, in a stacked state, the one negative electrode plate, the one of the two separators, the one positive electrode plate, and the other of the two separators; and cutting the two separators so that both ends of the two separators protrude from the ends of the positive electrode plate and the negative electrode plate in order to obtain a sub-unit in which the one negative electrode plate, the one of the two separators, the one positive electrode plate, and the other of the two separators are integrated.

Description

[Document name] Detail child

Patent application title: METHOD FOR MANUFACTURING LAMINATED ELECTRODE AND METHOD FOR MANUFACTURING STORAGE DEVICE

【Technical field】

【0 0 0 1】

The present invention relates to a method of manufacturing a laminated electrode body and a method of manufacturing a storage element.

【Background technology】

[0 0 0 2]

Chargeable and dischargeable storage elements are used in various devices such as mobile phones and electric vehicles. In recent years, with the increasing output and performance of these devices, storage devices that are smaller and have larger energy density (electrical capacity) are being sought.

[0 0 0 3]

In general, a storage element is formed by alternately laminating a positive electrode plate having a positive electrode active material layer formed on the surface and a negative electrode plate having a negative electrode active material layer formed on the surface via a separator having electrical insulation. It has a stacked electrode body. In order to increase the energy density per unit volume in such a storage element, it is effective to make the separator thinner. Therefore, a storage element in which a separator is formed of a resin film has been put to practical use.

[0 0 0 4]

In the storage element, a metal deposit formed by electrodeposition at the negative electrode (for example, a metal deposit due to dissolution and deposition of lithium foreign matter and metal foreign matter) may penetrate the separator and cause a short circuit between the positive electrode plate and the negative electrode plate. There is. With the use of a packaged electrode plate in which the outer edges of a pair of separators sandwiching the positive electrode plate or the negative electrode plate are adhered to form a bag, electrolytic species in the vicinity of the positive electrode plate may form precipitates There is known a laminated electrode assembly which suppresses corrosion and suppresses the electrodeposition of metal ions in contact with the negative electrode.

[0 0 0 5]

Since the bonded portion of the separator does not contribute to charging and discharging, the bonded portion of the separator may occupy a predetermined space inside the storage element to hinder the increase of the energy density of the storage element.

[0 0 0 6]

In the laminated electrode body, when the positive electrode plate protrudes from the negative electrode plate in plan view, current is concentrated at the end of the negative electrode plate, and electrodeposition is locally promoted. Therefore, in the laminated electrode body, the planar size of the positive electrode plate needs to be smaller than the planar size of the negative electrode plate, which is also a factor that limits the energy density of the storage element.

[0 0 0 7]

Since the separator formed from the resin film is relatively weak to heat, when the energy density of the storage element is increased, the separator is damaged by heat, and metal precipitates generated by electrodeposition penetrate the separator and the positive electrode plate There is a possibility of causing a short circuit between the and the negative electrode plate. Therefore, a storage element has been proposed in which a heat-resistant layer (inorganic layer) is formed on the surface of the separator in contact with the electrode plate to improve the heat resistance of the separator (Japanese Patent Application Laid-Open No. 20 13-14 3 3 3 7)).

【Prior Art Literature】

[Patent Document]

[0 0 0 8]

[Patent Document 1] Japanese Patent Application Laid-Open No. 2 0 1 3 1 3

SUMMARY OF THE INVENTION

[Problems to be solved by the invention]

[0 0 0 9]

In the storage element described in the above publication, a packaged positive plate in which the positive plate is sandwiched between a pair of separators and the pair of separators are adhered outside the plan view of the positive plate, and a bag larger than the positive plate and smaller than the separator A laminated electrode body in which non-packed negative electrode plates are alternately laminated is accommodated in the packaging material. A plurality of packaged positive electrode plates and a plurality of negative electrode plates are held by sandwiching the plurality of separators with the exterior material at the outer peripheral portion.

【0 0 1 0】 As described above, when alternately stacking a plurality of packaged positive electrode plates and a plurality of negative electrode plates, it is difficult to accurately position the negative electrode plate in the laminated electrode body. Since it is necessary to form the positive electrode plate small so that the positive electrode plate does not protrude from the negative electrode plate, improvement in energy density is hindered. In addition, even if the positive electrode plate is made smaller, it is necessary to position and position the negative electrode plate accurately on the packaged positive electrode plate, so the work of laminating a plurality of packaged positive electrode plates and a plurality of negative electrode plates is required. It is cumbersome and limits the improvement of manufacturing efficiency.

[0 0 1 1]

An object of the present invention is to provide a method of manufacturing a laminated electrode body and a method of manufacturing a storage element capable of efficiently manufacturing a laminated electrode body having a large energy density.

[Means for Solving the Problems]

[0 0 1 2]

In the method of manufacturing a laminated electrode assembly according to an aspect of the present invention, a positive electrode plate is disposed between two separators having adhesive layers on both sides, and one of the two separators is separated. Placing one negative electrode plate on the top, one negative electrode plate, one of the two separators, heating of the other one of the one positive electrode plate and the other of the two separators In order to obtain a combination of pressing, the one negative electrode plate, one of the two separators, the one positive electrode plate and the other of the two separators, the two sheets are integrated. Cutting the two separators so that both ends of the separator project from the ends of the positive electrode plate and the negative electrode plate, respectively.

【Effect of the invention】

[0 0 1 3]

In the method of manufacturing a laminated electrode body according to an aspect of the present invention, heat is applied to one positive electrode plate, two separators sandwiching the positive electrode plate, and one negative electrode plate laminated to one separator. Since the pressure-bonded and integrated unit is formed, the relative positions of the positive electrode plate, the separator and the negative electrode plate in this subunit are relatively accurate. Therefore, even if the difference between the size of the positive electrode plate and the size of the negative electrode plate is reduced, it is possible to prevent the positive electrode plate from protruding from the negative electrode plate and promoting the electrodeposition. In addition, in the sub unit, since the positive electrode plate and the negative electrode plate are adhered to the separator, the separator is not easily deformed. As a result, the subunits can be easily positioned by the guides, and multiple sheets can be accurately and quickly stacked. The ratio of the area of the region in which the positive electrode plate and the negative electrode plate are opposite to the area of the separator is relatively large, and a stacked electrode body having a large energy density can be efficiently manufactured.

Brief Description of the Drawings

[0 0 1 4]

FIG. 1 is a schematic cross-sectional view of a substrate formed in a method of manufacturing a laminated electrode body according to an embodiment of the present invention.

2 is a partial enlarged cross-sectional view of a subunit of the laminated electrode body of FIG. 1;

FIG. 3 is a schematic cross-sectional view of an electrode sheet formed in the method of manufacturing a laminated electrode body according to an embodiment.

4 is a schematic plan view of the electrode unit of FIG. 3;

5 is a schematic view showing a step of forming the substrate of FIG. 1; FIG.

FIG. 6 is a schematic cross-sectional view of a laminated electrode body manufactured by the method of manufacturing a laminated electrode body according to an embodiment.

FIG. 7 is a schematic exploded perspective view of an electric storage device manufactured by the method of manufacturing the electric storage device according to one embodiment.

MODE FOR CARRYING OUT THE INVENTION

[0 0 1 5]

In the method of manufacturing a laminated electrode assembly according to an aspect of the present invention, a positive electrode plate is disposed between two separators having adhesive layers on both sides, and one of the two separators is separated. Placing one negative electrode plate on the top, one negative electrode plate, one of the two separators, heating of the other one of the one positive electrode plate and the other of the two separators Press down In order to obtain a sheet that integrates the one negative electrode plate, one of the two separators, the one positive electrode plate, and the other of the two separators, the two separators are integrated. And cutting the two separators so that both end portions thereof project from the ends of the positive electrode plate and the negative electrode plate, respectively.

[0 0 1 6]

According to the method of manufacturing the laminated electrode body, one positive electrode plate, two separators sandwiching the positive electrode plate, and one negative electrode plate stacked on one separator are integrated by thermocompression bonding. Since the subunits are formed, the relative positions of the positive electrode plate, the separator, and the negative electrode plate in this subunit are relatively accurate. Therefore, even if the difference between the size of the positive electrode plate and the size of the negative electrode plate is reduced, it is possible to prevent the positive electrode plate from protruding from the negative electrode plate and promoting the electrodeposition. Further, in the subunit, since the positive electrode plate and the negative electrode plate are adhered to the separator, the separator is not easily deformed. Therefore, the subunits can be easily positioned by guides, and multiple subunits can be stacked accurately and quickly. The ratio of the area of the region where the positive electrode plate and the negative electrode plate are opposite to the area of the separator is relatively large, and a stacked electrode body having a large energy density can be efficiently manufactured.

[0 0 1 7]

In the manufacturing method of the laminated electrode body, in order to obtain an electrode sheet in which a plurality of the sheets are laminated and an electrode sheet obtained by integrating the plurality of laminated sheets is integrated, each of the plurality of sheets is used. And welding the separators protruding from the end of the positive electrode plate and the negative electrode plate. According to this configuration, the subunits are stacked and the end portions of the separators are welded to form an integrated electrode sheet. Thus, by laminating the electrode blocks, the layers are stacked more efficiently. An electrode body can be manufactured.

Conventionally, the packaged positive electrode plate is formed by sandwiching the positive electrode plate with a pair of separators and bonding or welding the pair of separators on the outside of the positive electrode plate in plan view. It has been difficult to improve manufacturing efficiency of such a packaged positive electrode plate. As described above, manufacturing efficiency can be improved by stacking a plurality of subunits and collectively welding the stacked separators.

[0 0 1 8]

The method of manufacturing the laminated electrode assembly includes: laminating a plurality of the electrode sheets; arranging a single negative electrode plate on the separator disposed in the outermost layer; and a plurality of the electrode sheets and the plurality of electrode sheets. And heating and pressing in a state in which the negative electrode plate is laminated. According to this configuration, by laminating and heating and pressing a plurality of electrode sheets and one negative electrode plate, it is possible to obtain a laminated electrode body in which all layers are adhered.

[0 0 1 9]

The method of manufacturing the laminated electrode body further includes: covering a periphery of a laminate of the plurality of electrode stacks and the negative electrode plate with a resin film before heating and pressing the plurality of electrode stacks and the negative electrode plate. May be According to this configuration, since the positional deviation of the plurality of electrode sheets and the negative electrode plate can be prevented at the time of handling when heating and pressing the laminate of the plurality of electrode units and the negative electrode plate, the positive electrode plate The energy density of the laminated electrode body can be further increased by reducing the margin for the displacement of the negative electrode plate.

[0 0 2 0]

The manufacturing method of the electrical storage element which concerns on 1 aspect of this invention, It comprises accommodating the laminated electrode body obtained by the said manufacturing method in a case.

[0 0 2 1]

In the method of manufacturing the storage element, a stacked electrode body having a large energy density is efficiently manufactured by the method of manufacturing the stacked electrode body, and a storage element is formed using this stacked electrode body. The element can be manufactured efficiently.

[0 0 2 2]

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings as appropriate.

[0 0 2 3]

A method of manufacturing a laminated electrode assembly according to an embodiment of the present invention is as follows: Forming a subunit s (sub-unit forming step); forming an electrode unit U as illustrated in FIGS. 3 and 4 by using a plurality of subunits S (electrode stack forming step); Integrating the plurality of electrode units U to obtain a laminated electrode body B as illustrated in FIG. 6 (integration step).

[0 0 2 4]

As shown in FIG. 1, the subunit S includes two separators 1, one positive electrode plate 2 disposed between the two separators 1 and adhesively fixed, and one of the two separators 1. And one negative electrode plate 3 bonded and fixed to the opposite surface. In the sheet, the ends of the two separators 1 project from the ends of the positive plate 2 and the negative plate 3.

[0 0 2 5]

As shown in detail in FIG. 2, the separator 1 comprises a sheet-like resin layer 4, an oxidation resistant layer 5 laminated on the surface of the resin layer 4 facing at least the positive electrode plate 2, the resin layer 4 and And a pair of adhesive layers 6 laminated on both sides of the laminate of the oxidation resistant layer 5.

[0 0 2 6]

The positive electrode plate 2 has a conductive foil- or sheet-like positive electrode current collector 7 and a positive electrode active material layer 8 laminated on the surface of the positive electrode current collector. More specifically, the positive electrode plate 2 includes an active material region having a rectangular shape in plan view in which the positive electrode active material layer 8 is stacked on the surface of the positive electrode current collector 7, and the positive electrode current collector 7 from the active material region. And a positive electrode tab 9 (see FIG. 4) extending in a band smaller than the active material region.

[0 0 2 7]

The negative electrode plate 3 has a conductive foil- or sheet-like negative electrode current collector 10 and a negative electrode active material layer 11 laminated on the surface of the negative electrode current collector 10. Specifically, the negative electrode plate 3 has an active material region having a rectangular shape in plan view, in which an active material layer is stacked on the surface of the negative electrode current collector 10, and a strip having a width smaller than that of the active material region from this active material region. , And a negative electrode tab 1 2 (see FIG. 4) spaced apart from the positive electrode tab 9 in the same direction as the positive electrode tab 9.

[0 0 2 8]

As shown in FIG. 3, the electrode unit U has a plurality of subunits S, and the ends of the separators 1 projecting from the ends of the positive electrode plate 2 and the negative electrode plate 3 of the plurality of subunits S are collectively It is welded.

[0 0 2 9]

In this electrode unit U, the positive electrode plate 2 is bonded and fixed to the separators 1 on both sides, but the negative electrode plate 3 is bonded and fixed only to the separator 1 of the same subunit S, and the adjacent It is not adhesively fixed to the separator 1.

[0 0 3 0]

As shown in FIG. 4, in the electrode unit U, a first welding region R 1 is formed along a pair of opposing side edges where the positive electrode tab 9 and the negative electrode tab 12 of the positive electrode plate 2 and the negative electrode plate 3 do not exist. It is preferable that The electrode unit U is formed by welding a plurality of separators 1 partially along the side edge where the positive electrode tab 9 and the negative electrode tab 12 of the positive electrode plate 2 and the negative electrode plate 3 are present and the side edge opposite thereto. Two welding areas R2 may be formed. In this case, it is preferable that the first welding area R 1 and the second welding area R 2 are not formed in the vicinity of the corners of the separator 1. The separators are bent in the thickness direction of the positive electrode plate 2 and the negative electrode plate 3 along the side edges of the positive electrode plate 2 and the negative electrode plate 3 in order to bring the plurality of separators 1 into close contact with each other. In this case, since bending in different directions interferes, welding at this part may cause excessive load and damage to the separator 1.

[0 0 3 1]

The laminated electrode body B is, as shown in FIG. 6, a plurality of laminated electrode units U and the electrode stack U, which is disposed further outside the separator 1 disposed outermost in the laminated body 1 And a negative electrode plate 3 of one sheet. In this laminated electrode body B, each negative electrode plate 3 is bonded and fixed not only to the same separator S 1 but also to the adjacent separator S 1. ing. In addition, the laminated electrode body B further includes a resin film 13 covering the entire laminated body (the outer periphery of the laminated body) of the plurality of electrode units U and one further negative electrode plate 3.

[0 0 3 2]

Although the thickness of the separator 1, the positive electrode plate 2 and the negative electrode plate 3 is drawn large in the figure for easy understanding, the actual thickness of the separator 1, the positive electrode plate 2 and the negative electrode plate 3 is small. The thickness of the welding regions R 1 and R 2 of the plurality of separators 1 is very small compared to the width of the welding regions R 1 and R 2. Therefore, the portions protruding from the positive electrode plate 2 and the negative electrode plate 3 including the first welding region R 1 of the separator 1 of each electrode unit U are along the end portions (side edges) of the positive electrode plate 2 and the negative electrode plate 3 Yore, even if it is folded.

[0 0 3 3]

In the method of manufacturing the laminated electrode body, the positive electrode plate 2 and the negative electrode plate 3 are relatively accurately positioned and fixed with respect to the two separators 1 by forming the above-described substrate S in the process of forming a laminate. You can get a copy S of your choice. By laminating a plurality of the sheets S, it is possible to form a multilayer electrode body B in which the plurality of positive electrode plates 2 and the plurality of negative electrodes 3 face each other with high precision via the separator 1.

[0 0 3 4]

As described above, in the method of manufacturing the laminated electrode body, the positive electrode plate 2 and the negative electrode plate 3 can be aligned with high accuracy and stacked by using the subunit S. Therefore, the positive electrode plate 2 and the negative electrode plate Even if the difference in size with 3 is reduced, it is possible to prevent the positive electrode plate 2 from protruding from the negative electrode plate 3 and promoting electrodeposition. Further, in the method of manufacturing the laminated electrode body, the difference in size between the negative electrode plate 3 and the separator 1 in the subunit S can also be reduced. Thereby, the area of the positive electrode plate 2, that is, the positive electrode plate 2 and the negative electrode plate 3 is smaller than the projected area of the laminated electrode body B (the area when viewed from the laminating direction of the separator 1, the positive electrode plate 2 and the negative electrode plate 3). And the area of the region to which the electrode plate contributes can be made relatively large to increase the energy density of the laminated electrode body B.

[0 0 3 5]

In addition to the fact that the outer edge portions of the separators 1 are bonded and fixed to each other, the subunit S is also bonded and fixed to the positive electrode plate 2 and the negative electrode plate 3 so that the separators 1 are unlikely to be stagnant. Therefore, by placing a guide or the like on the outer edge of the separator 1, the sheet S can be positioned relatively accurately and quickly, and the laminated electrode body B having a large energy density can be efficiently manufactured. be able to.

[0 0 3 6]

In the sheet forming step, one positive electrode plate 2 is disposed between two separators 1 and one negative electrode plate 3 is disposed on one of the two separators 1. Step (arranging step): Step of heating and pressing one negative electrode plate 3, one of two separators 1, one positive electrode plate 2 and the other of two separators 1 in this order (A heating and pressing process) and a process of cutting the two separators 1 so that both ends of the two separators 1 protrude from the ends of the positive plate 2 and the negative plate 3 (cutting process) And

[0 0 3 7]

The sheet forming step may be performed by using a separator 1 which has been cut first and then cut to the dimensions in the sheet S in advance, but as shown in FIG. The cutting step may be performed after the placement step and the sheet heating and pressing step are continuously performed using the sheet-like separator base material 1a.

[0 0 3 8]

Specifically, in the disposing step, the two separator base materials 1a are continuously supplied and transported in the long direction, and the size of the final product is measured between the two separator base materials 1a in this transport state. The positive plate 2 cut into two pieces is sequentially inserted at equal intervals (a pitch equal to the width of the subunit S), and the size of the final product is cut so as to face the positive plate 2 on the outside of one separator base material 1a. The arranged negative electrode plates 3 are sequentially arranged.

[0 0 3 9]

In the unit heating and pressing step, the long laminate is heated and pressurized while being conveyed continuously. Add Heat and pressure may be performed simultaneously. Alternatively, the laminate may be pressed after heating before the temperature of the adhesive layer 6 of the separator 1 drops to a temperature at which it loses adhesion.

[0 0 4 0]

Continuous conveyance of the laminate of the separator base material 1a, the positive electrode plate 2 and the negative electrode plate 3 can be performed using, for example, a conveyance belt or the like having releasability.

[0 0 4 1]

The heating of the laminate in the sheet heating and pressing step can be performed using, for example, a plate heater H or the like disposed so as to sandwich the laminate. In addition, pressurization in the unit heating and pressing process can be performed using, for example, a pair of pressure rollers P sandwiching the laminate. Alternatively, heating and pressing may be performed simultaneously using a pair of heating rollers which sandwich and heat the laminate.

[0 0 4 2]

The heating temperature in the sheet heating and pressing step is not lower than the temperature at which the adhesive layer 6 of the separator 1 develops adhesive strength and lower than the shutdown temperature of the resin layer 4, for example, 80 ° C. or higher. It can be less than ° C.

[0 0 4 3]

The pressure per unit length of the pressure roller can be, for example, not less than 0.1 NZ cm and not more than 10.0 NZ cm as a pressure applied in the sheet heating and pressing process.

[0 0 4 4]

In the cutting step, the sheets S are sequentially separated by cutting the separator base material 1 a with a cutter C to form a separator 1 of a predetermined length.

[0 0 4 5]

Here, each component of the subroutine S will be described in detail.

[0 0 4 6]

Separator 1 is an electric storage device manufactured using subunit S, and is interposed between positive electrode plate 2 and negative electrode plate 3 to prevent direct contact between positive electrode plate 2 and negative electrode plate 3. The inside thereof is impregnated with an electrolytic solution to enable transfer of charges via ions between the positive electrode plate 2 and the negative electrode plate 3.

[0 0 4 7]

The resin layer 4 of the separator 1 is a layer mainly holding an electrolytic solution, and is formed of a porous resin film.

[0 0 4 8]

The main component of the resin layer 4 is, for example, polyethylene (PE), polypropylene (PP), ethylene-acetate-butyl copolymer, ethylene-methyl atarelate copolymer, ethylene-butyl atylate copolymer, polyolefin derivatives such as chlorinated polyethylene, etc. Polyolefins such as ethylene-propylene copolymer, and polyesters such as polyethylene terephthalate and copolymerized polyester can be employed. Among them, polyethylene and polypropylene, which are excellent in electrolytic solution resistance, durability and weldability, are preferably used as the main component of the resin layer 4. The term "main component" means a component having the largest mass content.

[0 0 4 9]

The lower limit of the average thickness of the resin layer 4 is preferably, and more preferably 10 m. On the other hand, the upper limit of the average thickness of the resin layer 4 is preferably 3 0 / x m, more preferably 2 0 / x m. By setting the average thickness of the resin layer 4 to the above lower limit or more, it is possible to prevent the resin layer 4 from being broken when the separators 1 are welded. In addition, by setting the average thickness of the resin layer 4 to the above-described upper limit or less, the energy density of the substrate S and hence the laminated electrode body B can be increased.

[0 0 5 0]

The oxidation resistant layer 5 of the separator 1 is a layer mainly provided to suppress oxidation and deterioration of the resin layer 4 and includes a large number of inorganic particles and a binder connecting the inorganic particles.

[0 0 5 1] As a main component of the inorganic particles, for example, oxides such as alumina, silica, zirconia, titanium, magnesium, ceria, yttria, zinc oxide, iron oxide, etc. nitrides such as silicon nitride, titanium nitride, boron nitride and the like , Silicon carbide, calcium carbonate, aluminum sulfate, aluminum hydroxide, potassium titanate, talc, kaolin clay, kaolinite, halloysite, pyrophyllite, montmorillonite, sericite, myite, phamateite, bentonite, Examples include asbestos, zeolite, calcium borate and magnesium benzoate. Among them, as the main component of the inorganic particles of the oxidation resistant layer 5, alumina, silica and titanium are particularly preferable.

[0 0 5 2]

The lower limit of the average particle size of the inorganic particles of the oxidation resistant layer 5 is preferably 1 nm, more preferably 7 nm. On the other hand, the upper limit of the average particle size of the inorganic particles is preferably 5 / x m, more preferably 1 / x m. By setting the average particle diameter of the inorganic particles to the lower limit or more, the ratio of the binder in the oxidation resistant layer 5 can be reduced, and the heat resistance of the oxidation resistant layer 5 can be increased. In addition, by setting the average particle size of inorganic particles to the above-described upper limit or less, it is possible to form a homogeneous oxidation resistant layer 5. The “average particle size” is a value measured according to JIS-R1660 using a transmission electron microscope (T E M) or a scanning electron microscope (S E M).

[0 0 5 3]

The main component of the binder of the oxidation resistant layer 5 is, for example, fluorocarbon resin such as poly (vinyl fluoride), poly (tetrafluoroethylene), fluoro rubber such as poly (vinyl fluoride) -hexafluoropropylene-tetrafluoroethylene copolymer, styre -Butadiene copolymer and its hydride, acrylonitrile butadiene copolymer and its hydride, acrylonitrile butadiene-styrene copolymer and its hydride, methacrylate ester-acrylate ester copolymer, styrene Synthetic rubber such as acrylic ester copolymer, acrylonitrile acrylic ester copolymer etc., carboxymethyl cellulose (CMC), hydroxy cellulose (HEC), cellulose derivative such as ammonium salt of carboxymethyl cellulose, polyetherimiPolyamides such as poly, polyamidoimides, polyamides and their precursors (polyamic acid etc.), ethylene-acrylic acid copolymers such as ethylene / ethyl atalylate copolymer, polybul alcohol (PVA), polybul butyral (PVB And polyvinylidene-pyrrolidone (PVP), polyvinyl acetate-bi-nore, polyurethane, polyphenylene-le-tenole, poly-noselephone, poly-e-tenoreth / rehon, poly-phenylene-nephride, polyester and the like.

[0 0 5 4]

The lower limit of the average thickness of the oxidation resistant layer 5 is preferably 4 / x m. On the other hand, the upper limit of the average thickness of the oxidation resistant layer 5 is preferably 10 / x m, more preferably 6 / x m. By setting the average thickness of the oxidation resistant layer 5 to the above lower limit or more, it is possible to prevent the oxidation resistant layer 5 from being broken when the separator 1 is adhered and fixed. Further, by setting the average thickness of the oxidation resistant layer 5 to the above-mentioned upper limit or less, the oxidation resistant layer 5 is easily broken at the time of welding of the separators 1 to each other, so that the resin layers 4 can be integrated reliably. .

[0 0 5 5]

The adhesive layer 6 of the separator 1 is a layer which has ion conductivity so as to enable electrode reaction in the positive electrode plate 2 and the negative electrode plate 3 and which bonds the separator 1 to the positive electrode plate 2 and the negative electrode plate 3. . Specifically, the adhesive layer 6 exhibits adhesiveness by heating to a temperature higher than normal temperature, for example, 60 ° C. or higher and less than the shutdown temperature of the separator 1 (the temperature at which the resin layer 4 melts). Configured to

[0 0 5 6]

The adhesive layer 6 can be formed from a mixed material containing particles exhibiting ion conductivity and a binder. Specifically, the adhesive layer 6 is formed of a material containing solid electrolytic solution particles containing an electrolytic solution to secure ion conductivity, and a binder exhibiting adhesiveness by, for example, heating or ultrasonic vibration. be able to. The adhesive layer 6 preferably has continuous pores so that liquids and gases can pass through. [0 0 5 7]

The lower limit of the average thickness of the adhesive layer 6 is preferably 0.1 / x m, more preferably 0.2 / x m, and still more preferably 0.4 m. On the other hand, the upper limit of the average thickness of the adhesive layer 6 is preferably 3 / x m, more preferably 1.2 / x m. Sufficient adhesion can be obtained by setting the average thickness of the adhesive layer 6 to the above lower limit or more. Further, by setting the average thickness of the adhesive layer 6 to the upper limit or less, sufficient ion conductivity can be obtained.

[0 0 5 8]

Examples of the material of the solid electrolytic solution particles of the adhesive layer 6 include inorganic solid electrolytic solution, pure solid polymer electrolytic solution, polymer gel electrolytic solution (gel polar electrolyte), and the like. A polymer gel electrolyte which can increase the conductivity and is uniform and easy to adjust the particle size is particularly preferably used.

[0 0 5 9]

The polymer gel electrolyte is one which is made easy to handle by gelling the electrolyte with a polymer. Examples of the polymer that gels the electrolytic solution may include, for example, a fluorinated poly (vinylidene methacrylate) copolymer, polymethyl methacrylate, polyacrylonitrile and the like.

[0 0 6 0]

As the electrolyte of the polymer gel electrolyte, an organic electrolyte in which the supporting electrolyte is dissolved in an organic solvent is used. A lithium salt is preferably used as the supporting electrolyte. The lithium salt is not particularly limited. For example, L i PF 6 L i A s F ₆ L i BF ₄ L i S b F ₆ L i A 1 C 1 4, L i C 1 O ₄ , CF 3 SO 3 L i, C 4 F 9 SO 3 L i, CF 3 COO L i,

(CF 3 CO) ₂ NL i (CF 3 SO ₂ ) ₂ NL i, (C ₂ F 5 SO ₂ ) NL i and the like. Among _{them, L i PF 6 L i C} 1 0 4 CF 3 SO 3 L i which indicates a high degree of dissociation soluble in organic solvents are particularly preferred.

[0 0 6 1]

The organic solvent used in the electrolytic solution is not particularly limited as long as it can dissolve the supporting electrolytic solution, but, for example, dimethyl carbonate (DMC), ethylene carbonate (EC), diethylen carbonate (DEC), propylene Carbonates such as carbonate (PC), butylene carbonate (BC), methyl ethyl carbonate (ME C), for example, y-butyl ester, esters such as methyl formate, for example, 12-dimethoxetane, tetrahydrofuran It is possible to use one or more kinds in combination, such as ethers such as oral furan, sulfur-containing compounds such as sulfolane and dimethylsulfoxide. Among them, carbonates having a high dielectric constant and a wide stable potential region are particularly preferably used.

[0 0 6 2]

The lower limit of the concentration of the supporting electrolyte in the electrolyte is 1 mass. Is preferred, 5 mass. / ₀ is more preferable. On the other hand, the upper limit of the concentration of the supporting electrolyte in the electrolyte is 30 mass. / ₀ is preferable, 20 mass. / ₀ is more preferable. By setting the concentration of the support electrolyte in the electrolyte within the above range, relatively large ion conductivity can be obtained.

[0 0 6 3]

The lower limit of the average particle size of the solid electrolyte particles is preferably 0.1 μm, and more preferably 0.2 m. On the other hand, the upper limit of the average particle size of the solid electrolytic solution particles is preferably 2 / x m, more preferably 1 m. By setting the average particle diameter of the solid electrolytic solution particles to the above lower limit or more, it becomes easy to bring the solid electrolytic solution particles into contact with each other to impart ion conductivity to the adhesive layer 6. In addition, by setting the average particle diameter of the solid electrolytic solution particles to the upper limit or less, it becomes easy to form the adhesive layer 6 in a uniform film shape.

[0 0 6 4]

The shape of the solid electrolyte particles is preferably a shape having a small sphericity, such as a rod shape, a pyramid shape, or a plate shape, so as to promote the contact between the solid electrolyte particles and to increase the ion conductivity.

[0 0 6 5]

The binder of the adhesive layer 6 has adhesiveness to the solid electrolyte particle and the positive electrode active material layer 8. The resin that can adhere to the positive electrode active material layer 8 by heating at a relatively low temperature, that is, a polymer that has a relatively low glass transition temperature and exhibits adhesiveness. Materials are preferably used.

[0 0 6 6]

The lower limit of the glass transition temperature of the binder is preferably 50.degree. C., more preferably 45.degree. On the other hand, the upper limit of the glass transition temperature of the binder is preferably 50.degree. C., more preferably 45.degree. By setting the glass transition point of the binder to the lower limit or more, the strength of the adhesive layer 6 can be secured. In addition, by setting the glass transition point of the binder to the upper limit or less, the separator 1 can be bonded to the positive electrode plate 2 and the opposing separator 1 at a temperature at which the resin layer 4 is not damaged.

[0 0 6 7]

As a main component of a binder, an acrylic polymer etc. are mentioned, for example. As the acrylic polymer, a tolyl group-containing acrylic polymer containing a monomer unit having a tolyl group and a (meth) acrylic acid ester monomer unit is suitably used. Here, the monomer unit having a ditolyl group is a structural unit obtained by polymerizing, for example, acrylonitrile, methacrylonitrile or the like, and the (meth) acrylate monomer unit is, for example, CH z: ^ ^ ¹ — COOR

² (in the formula, R ¹ represents a hydrogen atom or a methyl group, and R ² represents an alkyl group or a cycloalkyl group) A monomer unit derived from a compound represented by the formula: The ditolyl group-containing acrylic polymer is formed by polymerizing an ethylenically unsaturated acid monomer in addition to a monomer unit having a ditolyl group and a (meth) acrylic acid ester monomer unit. It may contain an ethylenically unsaturated acid monomer unit. In addition, the acrylic polymer having a tolyl group may be crosslinked.

[0 0 6 8]

The lower limit of the ratio of solid electrolyte particles in the adhesive layer 6 is Ί 0 mass. / ₀ is preferred, 80 mass. / ₀ is more preferable. On the other hand, the upper limit of the ratio of the solid electrolyte particles in the adhesive layer 6 is preferably 95% by mass, and more preferably 90% by mass. By setting the ratio of the solid electrolytic solution particles in the adhesive layer 6 to the lower limit or more, sufficient ionic conductivity can be imparted to the adhesive layer 6. Further, by setting the ratio of the solid electrolytic solution particles in the adhesive layer 6 to the above-mentioned upper limit or less, the adhesive layer 6 can be provided with sufficient adhesiveness by setting the ratio of the binder relatively to a certain level or more.

【0 0 6 9】

As a material of the positive electrode current collector 7 of the positive electrode plate 2, a metal such as aluminum, copper, iron, nickel or an alloy thereof is used. Among these, aluminum, an aluminum alloy, copper and a copper alloy are preferable, and aluminum and an aluminum alloy are more preferable, from the viewpoint of the balance between the height of conductivity and the cost. In addition, as a formation form of the positive electrode current collector 7, a foil, a vapor deposition film, etc. may be mentioned, and a foil is preferable in terms of cost. That is, aluminum foil is preferable as the positive electrode current collector 7. In addition, as aluminum or aluminum alloy, A 1 0 8 5 P, A 3 0 0 3 P, etc. specified in J I S- H 4 0 0 0 (2 0 1 4) can be exemplified.

[0 0 7 0]

The lower limit of the average thickness of the positive electrode current collector 7 is preferably 5 / xm, more preferably 10 / xm. On the other hand, the upper limit of the average thickness of the positive electrode current collector 7 is preferably 50 / xm , 40 / xm is more preferable. By setting the average thickness of the positive electrode current collector 7 to the lower limit or more, sufficient strength can be imparted to the positive electrode current collector 7. In addition, by setting the average thickness of the positive electrode current collector 7 to the upper limit or less, the energy density of the substrate S and thus the laminated electrode body B can be increased.

[0 0 7 1]

The positive electrode active material layer 8 is formed of a so-called positive electrode mixture containing a positive electrode active material. In addition, the positive electrode composite material forming the positive electrode active material layer 8 contains optional components such as a conductive agent, a binder, a thickener, and a filler, as necessary.

[0 0 7 2]

As the positive electrode active material, for example, L i _x MO _y (where M represents at least one transition metal) Complex oxide (L i _x C o 0 ₂ , L i _x N i 0 ₂ , L i _x Mn ₂ 0 ₄ , L i _x M n O 3, L i _x N i _α C o ( i- _a ) 0 ₂ , L i _x N i _a Mn _{/ 3} C o (i- _α- β) 0 ₂ , L i _x N i _a Mn (2-a) 0 ₄ etc., L i _w M _x (XO _y ) _z (Me represents at least one transition metal, and X represents, for example, P, S i, B, V, etc.) (a Li F e P 0 ₄ , L i Mn _{P0 4, L i N i PO} 4, L i C o PO 4, L i 3 V 2 (PO 4) 3, L i 2 Mn S i 0 4, L i 2 C o P0 4 F , and the like) . The elements or polyions in these compounds may be partially substituted with other elements or species. In the positive electrode active material layer 8, one of these compounds may be used alone, or two or more thereof may be mixed and used. The crystal structure of the positive electrode active material is preferably a layered structure or a spinel structure.

[00 7 3]

The lower limit of the content of the positive electrode active material in the positive electrode active material layer 8 is 50 mass. / ₀ is preferred, 70 mass. / ₀ is more preferable, 80 mass. / ₀ is more preferable. On the other hand, the upper limit of the content of the positive electrode active material is 99 mass. / ₀ is preferred, 94 mass. / ₀ is more preferable. By setting the content of the positive electrode active material particles in the above range, it is possible to increase the energy density of the substrate S and thus the laminated electrode body B.

[00 74]

The conductive agent is not particularly limited as long as the conductive material does not adversely affect the battery performance. As such a conductive agent, carbon black such as natural or artificial graphite, furnace black, acetylene black and ketjen black, metal, conductive ceramics and the like can be mentioned. The shape of the conductive agent may, for example, be powdery or fibrous.

[00 7 5]

The lower limit of the content of the conductive agent in the positive electrode active material layer 8 is 0.1 mass. / ₀ is preferred, 0.5 mass. / ₀ is more preferable. On the other hand, the upper limit of the content of the conductive agent is 10 mass. / ₀ is preferred, 5 mass. / ₀ is more preferable. By setting the content of the conductive agent in the above range, the energy density of the subunit S and, in turn, the laminated electrode body B can be increased.

[00 7 6]

Examples of the binder include thermoplastic resins such as fluorine resin (polytetrafluoroethylene (PTF E), polyfluorinated biphenyl (PVDF), etc.), polyethylene, polypropylene, polyimide, etc., for example, ethylene propylene rubber (E PDM) And sulfonated EPDM, styrene butadiene rubber (SBR), elastomers such as fluororubber, and polysaccharide macromolecules.

[00 7 7]

The lower limit of the binder content in the positive electrode active material layer 8 is 1 mass. / ₀ is preferred, 2 mass. / ₀ is more preferable. On the other hand, the upper limit of the binder content is 10 mass. / ₀ is preferred, 5 mass. / ₀ is more preferable. By setting the content of the binder in the above range, the positive electrode active material can be stably held.

[00 7 8]

Examples of the thickener include polysaccharide polymers such as carboxymethylcellulose (CMC) and methylcellulose. When the thickener has a functional group that reacts with lithium, it is preferable to deactivate the functional group beforehand by methylation or the like.

[00 7 9]

The filler is not particularly limited as long as it does not adversely affect the battery performance. As the main component of the filler, polypropylene, polyethylene and other polyolefins, silica, alumina, zeolite, glass, carbon and the like can be mentioned.

[00 8 0]

The lower limit of the average thickness of the positive electrode active material layer 8 is preferably 10 / xm, more preferably 20 / xm. On the other hand, the upper limit of the average thickness of the positive electrode active material layer 8 is preferably 100 / xm, more preferably 80m. The positive electrode reaction can be sufficiently activated by setting the average thickness of the positive electrode active material layer 8 to the above lower limit or more. In addition, the average thickness of the positive electrode active material layer 8 is equal to or less than the upper limit. By doing this, it is possible to increase the energy density of the substrate S and hence the laminated electrode body B.

[008 1]

The negative electrode current collector 10 of the negative electrode plate 3 may have the same configuration as that of the positive electrode current collector 7 described above, but as a material, copper or a copper alloy is preferable. That is, copper foil is preferable as the negative electrode current collector 10 of the negative electrode plate 3. Examples of copper foils include rolled copper foils and electrolytic copper foils.

[0082]

The negative electrode active material layer 11 is formed of a so-called negative electrode plate composite material containing a negative electrode active material. Further, the negative electrode plate composite material forming the negative electrode active material layer 11 contains optional components such as a conductive agent, a binder, a thickener, and a filler, as necessary. As the optional components such as the conductive agent, the binder, the thickener, and the filler, those similar to the positive electrode active material layer 8 can be used.

[0083]

As the negative electrode active material, a material capable of inserting and extracting lithium ions is preferably used. Specific examples of the negative electrode active material include metals such as lithium and lithium alloy, metal oxides, polyphosphate compounds, and carbon materials such as graphite and amorphous carbon (graphitizable carbon or non-graphitizable carbon). Etc.

[0084]

Among the above-mentioned negative electrode active materials, from the viewpoint of setting the discharge capacity per unit opposing area between the positive electrode plate 2 and the negative electrode plate 3 in an appropriate range, Si, Si oxide, Sn, Sn oxide or these oxides It is preferable to use the combination of and particularly preferable to use Si oxide. Note that 3 1 and 3 1 can have a discharge capacity about three times that of graphite when made into an oxide.

[0085]

When using a Si oxide as the negative electrode active material, the ratio of the number of atoms to Si of O contained in the Si oxide is preferably more than 0 and less than 2. That is, a compound represented by S i O _x (0 <X <2) is preferable as the S i oxide. The ratio of the number of atoms is more preferably 0.5 or more and 1.5 or less.

[0086]

As the negative electrode active material, those mentioned above may be used alone or in combination of two or more. For example, by mixing and using Si oxide and another negative electrode active material, the discharge capacity per unit opposing area of the positive electrode plate 2 and the negative electrode plate 3 and the above-mentioned positive electrode active with respect to the mass of the negative electrode active material described later. Both mass ratios of the substances can be adjusted to be suitable values. Other negative electrode active materials used in combination with the S i oxide include carbon materials such as graphite, hard carbon, soft carbon, cotas, acetylene black, ketjen black, vapor grown carbon fiber, fullerene, activated carbon and the like. Be One of these carbon materials may be mixed with the S i oxide, or two or more may be mixed with the S i oxide in any combination and ratio. Among these other negative electrode active materials, graphite having a relatively low charge / discharge potential is preferable. By using graphite, a secondary battery element with high energy density can be obtained. Examples of the graphite mixed with the S i oxide include scaly graphite, spherical graphite, artificial graphite, natural graphite and the like. Among these, scale-like graphite is preferred which easily maintains contact with the surface of the Si oxide particles even after repeated charge and discharge.

[0087]

Furthermore, the negative electrode active material layer 11 is a typical nonmetallic element such as B, N, P, F, C1, Br, I etc. in addition to the S i oxide, L i, Na, Mg, Al Typical metal elements such as K, Ca, Zn, Ga and Ge, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Mo, Zr, T It may contain transition metal elements such as a, H f, Nb and W.

[0088]

It is preferable to use what contains both the phases of S i 0 ₂ and S i as said S i oxide (substance represented by general formula S i O _x ). Such a Si oxide occludes and desorbs lithium in Si in the matrix of Si ₂ O ₂ , so that the volume change is small and the charge-discharge cycle characteristics are excellent.

[0089] The average particle diameter of the Si oxide is preferably 1 μm or more and 15 m or less. By setting the average particle diameter of the Si oxide to the above-described upper limit or less, the charge-discharge cycle characteristics of the substrate S and, in turn, the laminated electrode body B can be improved.

[0 0 9 0]

The Si oxides can be used from highly crystalline ones to amorphous ones. Furthermore, as the Si oxide, one that has been washed with an acid such as hydrogen fluoride or sulfuric acid or one that has been reduced with hydrogen may be used.

[0 0 9 1]

The lower limit of the content of S i oxide in the negative electrode active material is 30 mass. / ₀ is preferred, 50 mass. / _{0 is} more preferable, 70 mass. / ₀ is more preferable. On the other hand, the upper limit of the Si oxide content is usually 100 mass. / ₀ , 90 mass. / ₀ is preferable.

[0 0 9 2]

The lower limit of the content of the negative electrode active material in the negative electrode active material layer 11 is 60 mass. / ₀ is preferred, 80 mass. / ₀ is more preferable and 90% by mass is further preferable. On the other hand, the upper limit of the content of the negative electrode active material is 99 mass. / ₀ is preferred, 9 8 mass. / ₀ is more preferable. By setting the content of the negative electrode active material particles in the above range, it is possible to increase the energy density of the subunit S and hence the laminated electrode body B.

[0 0 9 3]

As a lower limit of the content of the binder in the negative electrode active material layer 11, 1 mass. Is preferred, 5 mass. / ₀ is more preferable. On the other hand, the upper limit of the binder content is 20 mass. / ₀ is preferred, 15 mass. / ₀ is more preferable. By setting the content of the binder in the above range, the negative electrode active material can be stably held.

[0 0 9 4]

The lower limit of the average thickness of the negative electrode active material layer 11 is preferably 10 / x m, more preferably 20 / x m. Conversely, the upper limit of the average thickness of the negative electrode active material layer 11 is preferably 100 / x m, more preferably 80 / x m. The negative electrode reaction can be sufficiently activated by setting the average thickness of the negative electrode active material layer 11 to the above lower limit or more. In addition, by setting the average thickness of the negative electrode active material layer 11 to the above-described upper limit or less, the energy density of the substrate S and thus the stacked electrode body B can be increased.

[0 0 9 5]

In the electrode sheet formation step in the method of manufacturing the laminated electrode body, the step of laminating a plurality of substrates S (sub-unit laminating step), the positive electrode plate 2 of each of the plurality of laminated subunits S and the negative electrode And a step of welding the separators 1 protruding from the end of the plate 3 (welding step). In the electrode unit forming step, a step of trimming the outer portions of the plurality of welded separators 1 (trimming step) and a step of bending the welded portions of the plurality of separators 1 along the side edges of the positive electrode plate 2 and the negative electrode plate 3 (Bending process) and may be further equipped.

[0 0 9 6]

In the subunit lamination step, a plurality of subunits S are oriented in the same direction and laminated. As a result, a plurality of positive electrode plates 2 and a plurality of negative electrode plates 3 are alternately disposed with the separator 1 in between, and a laminate in which the separators 1 are disposed further outside the outermost positive electrode plate 2 is formed.

[0 0 9 7]

A stack of a plurality of sheets S is, for example, using a guide or the like that abuts on the outer edge of the square of the separator 1 and sequentially guides the sheets S formed in the above-described sheet forming step. It is possible to do it relatively quickly and accurately by putting in and putting up the sheets S by gravity.

[0 0 9 8]

The number of subunits S to be stacked can be, for example, 5 or more and 15 or less. By setting the number of stacked sheets S in this range, the distance between the separators 1 on both outer sides does not become too large. Thus, the end portions of the positive electrode plate 2 and the negative electrode plate 3 of each subunit S Even if the length of the separator 1 protruding from the side is reduced, the end portions of the separator 1 are bundled and welded, Since a plurality of sheets S can be integrated, the amount of use of the separator 1 can be reduced.

[0 0 9 9]

In the welding step, the end portions of all the separators 1 are bundled and welded so as to be in close contact with each other. Specifically, the oxidation resistant layer 5 of the separator 1 is broken to weld the resin layers 4 together. For this reason, welding of the separator 1 is preferably performed using an ultrasonic vibration indenter (horn). In addition, by using, for example, a large number of fine projections formed on the contact surface as an ultrasonic vibration indenter, the oxidation resistant layer 5 is broken and fragments of the oxidation resistant layer 5 are separated. Thus, the resin layers 4 can be welded efficiently.

[0 1 0 0]

In the trimming process, the portions protruding to the outside of the welding regions R1, R2 of the separator 1 are cut off. The separator 1 is designed to have the minimum size that can form the welding regions R 1 and R 2, but by bundling the plurality of separators 1 in close contact with each other in the welding step, the two-dot chain lines in FIG. As the end of the separator 1 is shifted in a step-like manner depending on the thickness of the positive electrode plate 2 and the negative electrode plate 3, the welding regions R 1 and R 2 formed in the portion where all the separators 1 are stacked. The separator 1 will protrude to the outside. Therefore, in this trimming step, the portions projecting in a step-like manner outside the welding regions R 1 and R 2 are mainly cut off. As a result, when the laminated electrode body B is formed, the energy density of the laminated electrode body B can be increased by reducing the dead space occupied by the separator 1 outside the welding regions R 1 and R 2. .

[0 1 0 1]

In the bending step, portions of the separator 1 that project from the positive electrode plate 2 and the negative electrode plate 3 are bent along the side edges of the positive electrode plate 2 and the negative electrode plate 3. As a result, when the laminated electrode body B is formed, the energy density of the laminated electrode body B can be increased by reducing the dead space occupied by the portions protruding from the positive electrode plate 2 and the negative electrode plate 3 of the separator 1. .

[0 1 0 2]

The integration step in the method of manufacturing the laminated electrode body includes a step of laminating a plurality of electrode stacks U (electrode unit laminating step) and a step of arranging one negative electrode plate 3 on the separator 1 disposed in the outermost layer A step of arranging a negative electrode plate) and a step of heating and pressing in a state in which a plurality of electrode sheets U and a negative electrode plate 3 are stacked (electrode body heating and pressing step). Moreover, this integration step further includes the step of covering the outer periphery of the laminate of the plurality of electrode sheets U and the negative electrode plate 3 with the resin film 13 (resin film wrapping step) before the electrode body heating and pressing step. Preferred to be equipped ,.

[0 1 0 3]

In the electrode unit laminating step, a plurality of electrode units u are oriented in the same direction and laminated. That is, between adjacent two electrode units U, the separator 1 of the other electrode unit U abuts the negative electrode plate 3 of one electrode unit U. Thus, a laminate in which a plurality of positive electrode plates 2 and negative electrode plates 3 are stacked via the separator 1 is formed.

[0 1 0 4]

In the negative electrode plate disposing step, the negative electrode plate 3 is disposed on both outer sides by further laminating the negative electrode plate 3 on the outer side of the separator 1 disposed in the outermost layer, and the plurality of positive electrode plates 2 and the negative electrode plates 3 are respectively separators Form a laminated body alternately stacked via 1.

[0 1 0 5]

It should be noted that “arranging one negative electrode plate on the separator” does not intend to limit the upper / lower relationship between the plurality of electrode units U and the negative electrode plate 3 to be supported, and the two outermost layers are laminated. One of the electrode sets U in which the negative electrode plate 3 is in contact with the separator 1 of the adjacent electrode set U. Further outside the separator 1 on the opposite side of the negative electrode plate 3 of the electrode set U. It means that the additional negative electrode plate 3 is laminated on Therefore, a single negative electrode plate 3 may be placed first, and multiple electrode seats may be stacked on top of it.

[0 1 0 6]

In the resin film rubbing process, a plurality of electrode sheets U and one further negative electrode plate 3 By covering the laminated body with the resin film 13, the plurality of electrode sheets U and the negative electrode plate 3 are held so as not to be displaced in the next electrode body heating and pressing process.

[0 1 0 7]

As described above, the resin film 13 prevents positional deviation of the separator 1, positive electrode plate 2 and negative electrode plate 3 in the electrode body heating and pressing process, thereby providing a margin for positional deviation of the positive electrode plate 2 and negative electrode plate 3. Can be made smaller to make the facing area of the positive electrode plate 2 and the negative electrode plate 3 larger, and the energy density of the laminated electrode body B can be further improved.

[0 1 0 8]

In addition, the resin film 13 covering the laminate of the plurality of electrode sheets U and the negative electrode plate 3 protects the negative electrode plate 3 on both outer sides, and in particular, the manufacture of a storage element described later can be facilitated.

[0 1 0 9]

Examples of the main component of the resin film 13 include polypropylene (PP), polyethylene (PE), polyethylene terephthalate (PET) and the like. Among them, as a main component of the resin film 13, polypropylene having a good heat sealability is particularly preferable.

[0 1 1 0]

The lower limit of the average thickness of the resin film 13 is preferably 20 / xm, more preferably 50 / xm. On the other hand, the upper limit of the average thickness of the resin film 13 is preferably 150 / xm, more preferably 100 / xm. By making the average thickness of the resin film 13 equal to or more than the above lower limit, it is possible to prevent the positional deviation of the plurality of electrode sheets U and the negative electrode plate 3 and to protect the negative electrode plate 3 without breakage. it can. Further, by making the average thickness of the resin film 13 equal to or less than the above upper limit, it is possible to coat the laminate of the plurality of electrode sheets U and the negative electrode plate 3 easily and without gaps, so The effect of preventing the misalignment of the soot U and the negative electrode plate 3 can be ensured, which contributes to the improvement of the energy density of the laminated electrode body B.

[0 1 1 1]

In the electrode body heating and pressing step, adjacent sheets S are preferably formed by heating and pressing a laminate of a plurality of electrode sheets U and one negative electrode plate 3 covered with a resin film 13. The separator 1 and the negative electrode plate 3 are joined to each other between the outer electrode sheet U and the outermost electrode sheet U. As a result, a laminated electrode body B in which all the separators 1, the positive electrode plate 2 and the negative electrode plate 3 are adhered and fixed to each other is obtained.

【0 1 1 2】

In the method of manufacturing a storage element according to one embodiment of the present invention, a step of housing laminated electrode body B obtained by the above-described method of manufacturing laminated electrode body in case 14 as shown in FIG. And the step of filling the case 14 with an electrolyte (electrolyte filling step).

【0 1 1 3】

The case 14 has a bottomed square cylindrical case body 15 and a plate-like lid 16 for sealing the opening of the case body 15. The storage element shown in FIG. 7 includes a positive electrode external terminal 17 and a negative electrode external terminal 18 provided to penetrate the lid 16, and a positive electrode external terminal 17 and a negative electrode external terminal 18 inside the case 14. A positive electrode connecting member 19 and a negative electrode connecting member 20 to which the positive electrode tab 9 and the negative electrode tab 12 of the laminated electrode body B are connected are provided.

【0 1 1 4】

Case 14 is a sealed container that accommodates the stacked electrode assembly B and in which the electrolytic solution is sealed. 【0 1 1 5】

The material of the case 14 may be, for example, a resin or the like as long as it has a sealing property capable of sealing the electrolyte and a strength capable of protecting the laminated electrode body B, but metal is preferably used. Ru. In other words, the case 14 may be, for example, a flexible bag formed of a laminate film, but a rigid metal case capable of more reliably protecting the laminated electrode B may be used. preferable.

[0 1 1 6]

As an electrolytic solution to be enclosed in the case 14 together with the laminated electrode B, it is usually used for the storage element. Known electrolytes, for example, cyclic carbonates such as ethylene carbonate (EC), propylene carbonate (PC) and butylene carbonate (BC), or jetyl carbonate (DEC), dimethinole carbonate (DMC), and acetylene It is possible to use a solution in which lithium hexafluorophosphate (L i PF ₆ ) or the like is dissolved in a solvent containing a linear carbonate such as methinoleic carbonate (EMC).

【0 1 1 7】

In the laminated electrode body accommodation step, the positive electrode tab 9 and the negative electrode tab 12 are connected to the positive electrode connecting member 19 and the negative electrode connecting member 20, respectively, and then the laminated electrode body B is inserted into the case main body 15 Seal the opening of case body 15 with body 16

【0 1 1 8】

As a method of connecting the positive electrode tab 9 and the negative electrode tab 12 to the positive electrode connecting member 19 and the negative electrode connecting member 20, for example, ultrasonic welding, laser welding, caulking or the like can be employed.

【0 1 1 9】

In the electrolyte filling step, the electrolyte is injected into the case 14. For this purpose, the case 14 is preferably provided with a sealable inlet.

[0 1 20]

According to the method of manufacturing the storage element, the stacked electrode body B having a high energy density is efficiently manufactured by the above-described method of manufacturing the stacked electrode body, and the storage element is manufactured using the stacked electrode body B. A storage element with a large energy density can be manufactured efficiently.

[0 1 2 1]

The above embodiment does not limit the configuration of the present invention. Therefore, the above embodiment can omit, replace, or add the components of the above embodiments based on the description in the present specification and technical common sense, and all of them can be construed as belonging to the scope of the present invention. It should.

[0 1 2 2]

In the manufacturing method of the laminated electrode assembly, a plurality of subunits are laminated without forming an electrode sheet in which a plurality of separators are welded, and a further negative electrode plate is used as the outermost separator of the subunit laminate. A laminated electrode body may be formed by heating and pressing the laminated ones.

【0 1 2 3】

In the method of manufacturing the laminated electrode body, the laminated electrode body may be manufactured by heating and pressing the laminated body in which the negative electrode plate is laminated on one electrode stack.

【Industrial applicability】

[0 1 24]

The method of manufacturing a stacked electrode assembly and the method of manufacturing a storage element according to the present invention can be used to manufacture various storage elements, but in particular, vehicles such as electric vehicles and plug-in hybrid electric vehicles (PHEVs) It is preferably used to manufacture a secondary battery used as a power source of

[Description of the code]

【0 1 2 5】

1 Seno Pass. Rater

2 Positive plate

3 Negative plate

4 resin layer

5 Oxidation resistant layer

6 Adhesive layer

7 Positive current collector

8 Positive electrode active material layer

9 Positive tab

10 Negative current collector

1 1 Negative electrode active material layer 1 2 Negative electrode tab

1 3 Resin film

1 4 Case

1 5 Case body

1 6 lid

1 7 Positive external terminal

1 8 Negative external terminal

1 9 Positive electrode connection member

20 Negative electrode connection member

B stacked electrode body

C Katsuta

H plate heater

P pressure roller

S subunit

U electrode unit

Claims

【Document Name】 Scope of Claims

[Claim 1]

Disposing one positive electrode plate between two separators having adhesive layers on both sides and disposing one negative electrode plate on one of the two separators;

Heating and pressing in a state where the other of the one negative electrode plate, one of the two separators, the positive electrode plate of the one sheet, and the other of the two separators are stacked;

In order to obtain a composite in which the one negative electrode plate, one of the two separators, the one positive electrode plate, and the other of the two separators are integrated, both ends of the two separators Cutting the two separators so that the respective portions project from the ends of the positive electrode plate and the negative electrode plate.

Method of producing a laminated electrode assembly comprising:

[Claim 2]

Stacking a plurality of the sheets;

In order to obtain an electrode sheet in which the plurality of stacked sheets are integrated, separators protruding from the end portions of the positive electrode plate and the negative electrode plate of each of the plurality of sheets are welded. Things

The method for producing a laminated electrode body according to claim 1, further comprising:

[Claim 3]

Stacking a plurality of the electrode sheets;

Placing a negative electrode plate on the separator disposed in the outermost layer;

The method according to claim 2, further comprising: heating and pressing in a state in which the plurality of electrode stacks and the negative electrode plate are stacked.

[Claim 4]

The laminated electrode according to claim 3, further comprising covering the outer periphery of the laminate of the plurality of electrode sheets and the negative electrode plate with a resin film before heating and pressing the plurality of electrode sheets and the negative electrode plate. How to make the body.

[Claim 5]

Housing the laminated electrode body obtained by the manufacturing method according to any one of claims 1 to 4 in a case.

Method of manufacturing a storage element comprising: