CN112119523A - Laminated battery - Google Patents
Laminated battery Download PDFInfo
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- CN112119523A CN112119523A CN201980032978.7A CN201980032978A CN112119523A CN 112119523 A CN112119523 A CN 112119523A CN 201980032978 A CN201980032978 A CN 201980032978A CN 112119523 A CN112119523 A CN 112119523A
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Classifications
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
- H01M50/40—Separators; Membranes; Diaphragms; Spacing elements inside cells
- H01M50/463—Separators, membranes or diaphragms characterised by their shape
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M10/00—Secondary cells; Manufacture thereof
- H01M10/04—Construction or manufacture in general
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M10/00—Secondary cells; Manufacture thereof
- H01M10/05—Accumulators with non-aqueous electrolyte
- H01M10/058—Construction or manufacture
- H01M10/0583—Construction or manufacture of accumulators with folded construction elements except wound ones, i.e. folded positive or negative electrodes or separators, e.g. with "Z"-shaped electrodes or separators
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M10/00—Secondary cells; Manufacture thereof
- H01M10/05—Accumulators with non-aqueous electrolyte
- H01M10/058—Construction or manufacture
- H01M10/0585—Construction or manufacture of accumulators having only flat construction elements, i.e. flat positive electrodes, flat negative electrodes and flat separators
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
- H01M50/40—Separators; Membranes; Diaphragms; Spacing elements inside cells
- H01M50/409—Separators, membranes or diaphragms characterised by the material
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
- H01M50/40—Separators; Membranes; Diaphragms; Spacing elements inside cells
- H01M50/489—Separators, membranes, diaphragms or spacing elements inside the cells, characterised by their physical properties, e.g. swelling degree, hydrophilicity or shut down properties
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/10—Energy storage using batteries
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P70/00—Climate change mitigation technologies in the production process for final industrial or consumer products
- Y02P70/50—Manufacturing or production processes characterised by the final manufactured product
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- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- General Chemical & Material Sciences (AREA)
- Secondary Cells (AREA)
- Engineering & Computer Science (AREA)
- Manufacturing & Machinery (AREA)
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Abstract
A stacked battery (1) is provided with: a plurality of electrode plates (10, 20) and an insulating sheet (30) are laminated in the lamination direction (dL). The insulating sheets (30) are alternately folded back in a width direction (d1) that is not parallel to the stacking direction (dL), and are arranged between two electrode plates (10, 20) that are adjacent in the stacking direction (dL). A gap (40) is provided between the folded-back sections (33, 34) of the insulating sheet (30) and the end sections (10a, 20b) of the electrode plates (10, 20) facing the folded-back sections in the width direction (d 1). The length in the width direction (d1) between the folded sections (33, 34) and the end sections (10a, 20b) of the electrode plates (10, 20) facing the folded sections (33, 34) is 5 times or more the thickness of the electrode plates (10, 20).
Description
Technical Field
The present invention relates to a stacked battery.
Background
As described in JP2014-165055A, JP2013-182715a, a laminate type battery in which positive and negative electrode plates are alternately laminated is widely used. As an example of the stacked battery, a lithium ion secondary battery is cited. One of the characteristics of the lithium ion secondary battery is a large capacity as compared with other types of stacked batteries. Lithium ion secondary batteries having such characteristics are currently expected to be further widespread in various applications such as vehicle-mounted applications and stationary house applications.
In the laminate-type battery, for example, ions are transferred between the positive electrode plate and the negative electrode plate via the electrolyte solution, and charge and discharge are performed. For example, in the case of a lithium ion secondary battery, lithium ions in an electrolyte move from a positive electrode to a negative electrode to perform charging, and move from the negative electrode to the positive electrode to perform discharging. The electrolyte is held by an insulating sheet (separator) provided between the positive electrode plate and the negative electrode plate.
In the stacked battery shown in JP2014-165055a, an insulating sheet in a U-folded shape is provided between each of the positive and negative electrode plates. That is, the positive electrode plate and the negative electrode plate are provided between the folded surfaces of the insulating sheet. Such an insulating sheet can be easily produced by disposing 1 insulating sheet between the positive electrode plate and the negative electrode plate. In the stacked battery of JP2014-165055a, since the battery capacity (energy density) per unit volume increases, that is, the volume decreases, the insulating sheets are folded back so as not to generate a gap between the positive electrode plate and the negative electrode plate.
Here, when there is a portion of the insulating sheet that does not hold the electrolyte, the positive and negative electrode plates facing the portion do not contribute to charge and discharge, and therefore efficiency is insufficient when charging and discharging is performed. In particular, as described in JP2014-165055a, when the insulating sheet is U-folded, the electrolyte solution is not easily held in the vicinity of the folded portion. Therefore, the electrolyte cannot be sufficiently supplied near the end portions of the positive and negative electrode plates facing the folded portions of the insulating sheet, and it is difficult to contribute to charging and discharging. Therefore, the charge and discharge capacity of the stacked battery is reduced.
The laminate-type battery generally includes tens of positive electrode plates and tens of negative electrode plates. When the vicinity of the end portions of the respective positive and negative electrode plates does not contribute to charging and discharging, the efficiency of charging and discharging in the entire stacked type battery may be significantly deteriorated.
The laminate-type battery generally includes a laminate including positive electrode plates and negative electrode plates alternately laminated, and an insulator provided between the positive electrode plates and the negative electrode plates, and an outer package housing the laminate. The outer package generally has, from the viewpoint of barrier properties and strength: a main body portion made of metal, for example, aluminum alloy; and an insulating coating layer provided on the inner surface side of the main body. The insulating coating layer prevents short circuit between the electrode plate and the main body of the exterior package.
However, defects such as pinholes may occur on the insulating coating layer. For example, the insulating coating layer may be locally damaged by contact with the edge portion of the electrode plate. When the insulating coating layer is defective, the electrode plate and the exterior package are short-circuited, and the laminate type battery cannot exhibit a predetermined function.
Disclosure of Invention
< invention 1 >
The object of the invention 1 is to improve the efficiency of charge and discharge in a stacked type battery having an insulating sheet in a U-folded shape.
The stacked battery of claim 1 includes:
a plurality of electrode plates stacked in a stacking direction; and
insulating sheets which are alternately folded back in a width direction not parallel to the stacking direction and are arranged between two of the electrode plates adjacent in the stacking direction,
a gap is provided between the folded portion of the insulating sheet and an end portion of the electrode plate facing the folded portion in the width direction.
In the stacked cell according to claim 1, the folded portion may have irregularities.
In the stacked-type battery according to claim 1, a length in the width direction between the folded portion and an end portion of the electrode plate facing the folded portion may be 5 times or more a thickness of the electrode plate.
In the stacked-type battery according to claim 1, a length in the width direction between the folded portion and an end portion of the electrode plate facing the folded portion may be 10 times or more a thickness of the electrode plate.
In the stacked-type battery according to claim 1, the insulating sheet may have a base material layer formed of a porous body.
In the stacked-type battery according to claim 1, the insulating sheet may have a functional layer containing an inorganic material.
The stacked cell according to claim 1 may be:
the plurality of electrode plates includes: a1 st electrode plate and a 2 nd electrode plate alternately laminated in the lamination direction, a length of the 2 nd electrode plate in the width direction being larger than a length of the 1 st electrode plate in the width direction,
the fold-back section includes: a1 st turn-back portion in which one side of the insulating sheet is turned back in the width direction, and a 2 nd turn-back portion in which the other side of the insulating sheet is turned back in the width direction,
the 1 st folded portion is located closer to one side in the width direction than an end portion on one side in the width direction of a 2 nd electrode plate adjacent to a1 st electrode plate facing the 1 st folded portion.
The stacked cell according to claim 1 may be:
the plurality of electrode plates includes: a1 st electrode plate and a 2 nd electrode plate alternately laminated in the lamination direction, a length of the 2 nd electrode plate in the width direction being larger than a length of the 1 st electrode plate in the width direction,
the fold-back section includes: a1 st turn-back portion in which one side of the insulating sheet is turned back in the width direction, and a 2 nd turn-back portion in which the other side of the insulating sheet is turned back in the width direction,
the length in the width direction between the 1 st folded portion and the end portion on one side in the width direction of the 2 nd electrode plate adjacent to the 1 st electrode plate facing the 1 st folded portion is smaller than the length in the width direction between the 2 nd folded portion and the end portion on the other side in the width direction of the 2 nd electrode plate facing the 2 nd folded portion.
The stacked cell according to claim 1 may be:
the plurality of electrode plates includes: a1 st electrode plate and a 2 nd electrode plate alternately laminated in the lamination direction, a length of the 2 nd electrode plate in the width direction being larger than a length of the 1 st electrode plate in the width direction,
the insulating sheet has: a substrate layer and a functional layer laminated on the substrate layer and having a higher porosity than the substrate layer,
one side of the insulating sheet is provided with the substrate layer with the 1 st electrode board is face-to-face, be provided with one side of functional layer with the 2 nd electrode board is face-to-face.
The stacked cell according to claim 1 may be:
the plurality of electrode plates includes: a1 st electrode plate and a 2 nd electrode plate alternately laminated in the lamination direction, a length of the 2 nd electrode plate in the width direction being larger than a length of the 1 st electrode plate in the width direction,
the insulating sheet has: a substrate layer and a functional layer laminated on the substrate layer and having higher heat resistance than the substrate layer,
one side of the insulating sheet is provided with the substrate layer with the 2 nd electrode board is face-to-face, be provided with one side of functional layer with the 1 st electrode board is face-to-face.
The stacked-type battery of claim 1 may further include: an outer package body accommodating the electrode plate and the insulating sheet,
the folded portion is in contact with the exterior package.
The stacked cell of claim 1 may include 20 or more electrode plates in total.
With the invention of claim 1, it is possible to suppress a decrease in the capacity of charging and discharging in a stacked-type battery having an insulating sheet in a U-folded shape.
< invention 2 >
The object of the invention 2 is to effectively prevent short circuit between an exterior package and an electrode plate and to improve the reliability of a stacked battery.
The 1 st stacked-type battery according to the 2 nd invention includes:
a1 st electrode plate and a 2 nd electrode plate alternately laminated in a lamination direction; and
insulators alternately turned back in opposite directions in a width direction perpendicular to the stacking direction so as to extend between 1 st and 2 nd electrode plates adjacent in the stacking direction, wherein,
the insulator includes: a1 st folded portion folded back at one side in the width direction of one side end portion of the 1 st electrode plate located at one side in the width direction, and a 2 nd folded portion folded back at the other side in the width direction of the other side end portion of the 2 nd electrode plate located at the other side in the width direction,
the width of the 1 st electrode plate along the width direction is smaller than the width of the 2 nd electrode plate along the width direction,
the one-side end portion in the width direction of the 1 st folded portion is closer to one side in the width direction than a one-side end portion of the 2 nd electrode plate adjacent to the 1 st electrode plate corresponding to the 1 st folded portion.
The 2 nd stacked battery according to the 2 nd invention includes:
a1 st electrode plate and a 2 nd electrode plate alternately laminated in a lamination direction;
insulators alternately turned back in opposite directions in a width direction perpendicular to the stacking direction so as to extend between 1 st and 2 nd electrode plates adjacent in the stacking direction; and
an exterior packaging body accommodating the 1 st electrode plate, the 2 nd electrode plate, and the insulator, wherein,
the insulator includes: a1 st folded portion folded back at one side in the width direction of one side end portion of the 1 st electrode plate located at one side in the width direction, and a 2 nd folded portion folded back at the other side in the width direction of the other side end portion of the 2 nd electrode plate located at the other side in the width direction,
the 1 st folded portion and the 2 nd folded portion are in contact with the exterior packaging body, thereby restricting the 1 st electrode plate and the 2 nd electrode plate from being in contact with the exterior packaging body.
In the 1 st or 2 nd stacked cell according to claim 2, the one end of the 1 st folded portion may be shifted to one side in the width direction by 0.1mm or more from one end of the 2 nd electrode plate adjacent to the 1 st electrode plate corresponding to the 1 st folded portion.
In the 1 st or 2 nd stacked cell according to the 2 nd invention, the one side end of the 1 st folded portion may be shifted to one side in the width direction by 0.1mm or more and 3mm or less than one side end of the 2 nd electrode plate adjacent to the 1 st electrode plate corresponding to the 1 st folded portion.
In the 1 st or 2 nd stacked cell according to the 2 nd invention, the other end portion in the width direction of the 2 nd folded portion may be shifted by 3mm or less and 3mm or less to the other side in the width direction than the other end portion of the 2 nd electrode plate corresponding to the 2 nd folded portion.
In the 1 st or 2 nd stacked-type battery according to the 2 nd invention, a length of the 1 st folded portion protruding from the one end portion of the 1 st electrode plate to one side in the width direction may be larger than a length of the 2 nd folded portion protruding from the other end portion of the 2 nd electrode plate to the other side in the width direction.
In the 1 st or 2 nd stacked cell according to the 2 nd invention, the other end portion in the width direction of the 2 nd folded portion may be closer to the other side in the width direction than the other end portion of the 1 st electrode plate adjacent to the 2 nd electrode plate corresponding to the 2 nd folded portion.
The 1 st or 2 nd stacked battery according to claim 2 may be:
one side end portion of the 2 nd electrode plate is closer to one side in the width direction than one side end portion of the 1 st electrode plate,
the other end of the 2 nd electrode plate is closer to the other side in the width direction than the other end of the 1 st electrode plate.
The 1 st or 2 nd stacked cell according to the invention 2 may further include: an exterior packaging body accommodating the 1 st electrode plate, the 2 nd electrode plate and the insulator,
the 1 st folded-back portion is in contact with the exterior package in the width direction,
one end of the 2 nd electrode plate is separated from the exterior package in the width direction.
The 1 st or 2 nd stacked cell according to the invention 2 may further include: an exterior packaging body accommodating the 1 st electrode plate, the 2 nd electrode plate and the insulator,
the separation distance between one side end of the 2 nd electrode plate and the external packaging body along the width direction is more than 0.1 mm.
The 1 st or 2 nd stacked cell according to the invention 2 may further include: an exterior packaging body accommodating the 1 st electrode plate, the 2 nd electrode plate and the insulator,
the separation distance between one end of the 2 nd electrode plate and the external packaging body along the width direction is less than or equal to 3 mm.
The 1 st or 2 nd stacked battery according to claim 2 may be:
the external packaging body comprises: a1 st part and a 2 nd part, the 2 nd part being engaged with the 1 st part and forming a receiving space of the 1 st electrode plate, the 2 nd electrode plate and the insulator between the 1 st part and the 2 nd part,
the 2 nd member has: a bulging portion that forms the accommodation space, and a flange portion that is connected to the bulging portion so as to annularly surround the bulging portion and that is engaged with the 1 st member,
the bulging portion may have: a top wall portion that is at an angle greater than 90 ° and 110 ° or less with respect to the flange portion and rises from the flange portion, and an annular side wall portion that is connected to the side wall portion.
In the 1 st or 2 nd stacked cell according to claim 2, the pressure inside the exterior body may be 100kPa or less.
The 1 st or 2 nd stacked cell according to claim 2 may include 10 or more of the 1 st electrode plate and the 2 nd electrode plate, respectively.
According to the invention of claim 2, short circuit between the external packaging body and the electrode plate can be effectively prevented, and the reliability of the stacked battery can be improved.
In the stacked battery of claim 1 or 2 based on claim 2, the 1 st electrode plate may be a positive electrode plate, and the 2 nd electrode plate may be a negative electrode plate.
Drawings
Fig. 1 is a perspective view showing a stacked battery 1 according to embodiment 1 of the stacked battery 1.
Fig. 2 is a perspective view showing the interior of the stacked battery of fig. 1, with an exterior package, an insulating sheet, and the like removed.
Fig. 3 is a plan view showing a membrane electrode assembly included in the stacked cell of fig. 1.
Fig. 4 is a cross-sectional view taken along line IV-IV of fig. 1.
FIG. 5 is a view showing a part of a cross section taken along line V-V in FIG. 1.
Fig. 6 is an enlarged view showing one side in the width direction of the electrode plates and the insulating sheets of the stacked battery shown in fig. 5.
Fig. 7 is an enlarged view showing the other side in the width direction of the electrode plates and the insulating sheets of the stacked battery shown in fig. 5.
Fig. 8 is an enlarged view of the frame VIII in fig. 3.
Fig. 9 is a perspective view showing a stacked cell, illustrating embodiment 2 of the invention 2.
Fig. 10 is a perspective view showing the inside of the stacked battery of fig. 9 with an exterior package, an insulator, and the like removed.
Fig. 11 is a longitudinal sectional perspective view for explaining a stacked structure of electrode plates and insulators of the stacked battery of fig. 9.
Fig. 12 is a plan view showing an electrode plate and an insulator of the stacked battery of fig. 9.
Fig. 13 is a longitudinal sectional view showing a cross section of the stacked cell of fig. 9 in the width direction, i.e., along line XIII-XIII of fig. 12.
Fig. 14 is a partial longitudinal sectional view showing a section of the stacked battery of fig. 9 in a taking-out direction, that is, a section along the XIV-XIV line of fig. 9.
Fig. 15 is a partial longitudinal sectional view showing a cross section of the stacked cell of fig. 9 in the width direction.
Fig. 16 is a partial longitudinal sectional view showing a cross section of the stacked cell of fig. 9 in the width direction.
Detailed description of the invention
Hereinafter, embodiments of the invention will be described with reference to the drawings. In the drawings attached to the present specification, the scale and the vertical size ratio are appropriately changed and exaggerated from the actual ones for the convenience of understanding.
< embodiment 1 >
Fig. 1 to 8 are views for explaining embodiment 1 of the multilayer electrode according to embodiment 1. Fig. 1 is a perspective view showing an embodiment of a stacked battery. As shown in fig. 1, the stacked cell 1 includes: the exterior package 3, the membrane electrode assembly 5 housed in the exterior package 3, and the tab 4 connected to the membrane electrode assembly 5 and protruding from the inside of the exterior package 3 to the outside. As shown in fig. 2, the membrane electrode assembly 5 has a1 st electrode plate 10 and a 2 nd electrode plate 20 alternately stacked. In the example shown in fig. 1, the stacked cell 1 has a generally flat shape, expanding in the 1 st direction d1 as the width direction and the 2 nd direction d2 as the length direction.
Hereinafter, a lithium ion secondary battery constituted by the stacked battery 1 will be described as an example. In this example, the 1 st electrode plate 10 constitutes a positive electrode plate 10X, and the 2 nd electrode plate 20 constitutes a negative electrode plate 20Y. However, as will be apparent from the description of the operational effects described below, embodiment 1 described herein is not limited to a lithium ion secondary battery, and can be widely used for a stacked battery 1 in which the 1 st electrode plate 10 and the 2 nd electrode plate 20 are alternately stacked.
The exterior package 3 is a packaging material for sealing the film electrode assembly 5. The exterior package 3 has a housing space for housing the membrane electrode assembly 5. The exterior package 3 internally seals the film electrode assembly 5 and the electrolyte. An example of the exterior package 3 includes: two base materials, an adhesive layer disposed between the two base materials. The substrate preferably has high gas barrier properties and moldability. As such a substrate, an aluminum foil or a stainless steel foil can be used. On the other hand, the adhesive layer functions as a sealing layer for bonding two substrates. The adhesive layer preferably has, in addition to adhesiveness, insulation properties, chemical resistance, thermoplasticity, and the like. As such an adhesive layer, for example, there can be used: polypropylene, modified polypropylene, low density polypropylene, ionomer, ethylene vinyl acetate, and the like. The thickness of the exterior package 3 is, for example, 100 μm to 300 μm.
The tab 4 functions as a terminal in the stacked battery 1. A cross-section along line IV-IV of figure 1 is shown in figure 4. As shown in fig. 2 and 4, the positive electrode plate 10X (1 st electrode plate 10) of the membrane electrode assembly 5 is electrically connected to the tab 4 on one side (the side of the 2 nd direction d 2). Similarly, the negative electrode plate 20Y (the 2 nd electrode plate 20) of the membrane electrode assembly 5 is electrically connected to the tab 4 on the other side (the other side in the 2 nd direction d 2). The tab 4 may be formed using aluminum, nickel-plated copper, or the like. As shown in fig. 1, a pair of lugs extend from the inside of the outer package 3 to the outside of the outer package 3. As shown in fig. 4, a seal is formed between the outer package 3 and the terminal 4 in a region where the terminal 4 protrudes.
Next, the membrane electrode assembly 5 will be explained. As shown in fig. 3 to 5, the membrane electrode assembly 5 includes: a positive electrode plate 10X (1 st electrode plate 10), a negative electrode plate 20Y (2 nd electrode plate 20), and an insulating sheet 30. As shown in fig. 4, positive electrode plates 10X and negative electrode plates 20Y are alternately stacked in a stacking direction dL (vertical direction in fig. 4). The membrane electrode assembly 5 includes, for example, 20 or more positive electrode plates 10X and negative electrode plates 20Y in total. The membrane electrode assembly 5 has a flat shape as a whole, is thin in the stacking direction dL, and extends in a direction not parallel to the stacking direction dL. In the example shown in fig. 3, the membrane electrode assembly 5 is expanded in the 1 st direction d1 and the 2 nd direction d2 perpendicular to the stacking direction dL. The thickness of the membrane electrode assembly 5, that is, the length in the stacking direction dL, is, for example, 4mm to 20 mm.
In the non-limiting example shown, positive electrode plate 10X and negative electrode plate 20Y are plate-shaped electrodes having an outer contour of a rectangular shape. The 1 st direction d1 that is not parallel to the stacking direction dL is the width direction (width direction) of the positive electrode plate 10X and the negative electrode plate 20Y, and the 2 nd direction d2 that is not parallel to both the stacking direction dL and the 1 st direction d1 is the longitudinal direction of the positive electrode plate 10X and the negative electrode plate 20Y. In the illustrated example, the lamination direction dL, the 1 st direction d1, and the 2 nd direction d2 are perpendicular to each other. As shown in fig. 2 to 4, positive electrode plate 10X and negative electrode plate 20Y are arranged offset from each other in direction 2 d 2. More specifically, the plurality of positive electrode plates 10X are disposed closer to one side in the 2 nd direction d2, and the plurality of negative electrode plates 20Y are disposed closer to the other side in the 2 nd direction d 2. Positive electrode plate 10X and negative electrode plate 20Y overlap in lamination direction dL at the center of 2 nd direction d 2. Fig. 5 shows a part of a cross section of the laminate type battery 1 taken along the line V-V of fig. 1. As shown in fig. 5, the length of the negative electrode plate 20Y (the 2 nd electrode plate 20) in the 1 st direction d1 (the width direction) is greater than the length of the positive electrode plate 10X (the 1 st electrode plate 10) in the 1 st direction d 1. In the illustrated example, negative electrode plate 20Y protrudes to one side and the other side in 1 st direction d1 with respect to positive electrode plate 10X. The thickness of the positive electrode plate 10X and the negative electrode plate 20Y, that is, the length dL in the lamination direction is, for example, 4mm to 20mm, the length (width) in the width direction, that is, the 1 st direction d1 is, for example, 80mm to 250mm, and the length in the length direction, that is, the 2 nd direction d2 is, for example, 250mm to 500 mm.
As shown in fig. 4, the positive electrode plate 10X (1 st electrode plate 10) has: a positive electrode collector 11X (the 1 st electrode collector 11), and a positive electrode active material layer 12X (the 1 st electrode active material layer 12) provided on the positive electrode collector 11X. In the lithium ion secondary battery, the positive electrode plate 10X emits lithium ions during discharge and absorbs lithium ions during charge.
As shown in fig. 3 and 4, positive electrode current collector 11X has: the 1 st surface 11a and the 2 nd surface 11b opposed to each other serve as main surfaces. The positive electrode active material layer 12X is formed on both surfaces of the 1 st surface 11a and the 2 nd surface 11b of the positive electrode collector 11X. The plurality of positive electrode plates 10X included in the stacked battery 1 have a pair of positive electrode active material layers 12X provided on both sides of the positive electrode current collector 11X, and may have the same configuration.
The positive electrode current collector 11X and the positive electrode active material layer 12X can be produced by various production methods using various materials suitable for the stacked battery 1 (lithium ion secondary battery). As one example, the positive electrode collector 11X may be formed of aluminum foil. The positive electrode active material layer 12X includes, for example: a positive electrode active material, a conductive auxiliary agent, and a binder as a binder. The positive electrode active material layer 12X can be prepared by: a slurry for a positive electrode obtained by dispersing a positive electrode active material, a conductive auxiliary agent, and a binder in a solvent is applied to a material to be the positive electrode current collector 11X and cured. As the positive electrode active material, for example, a lithium metalate compound represented by a general formula LiMxOy (where M is a metal, and x and y are a composition ratio of the metal M and oxygen O) is used. Specific examples of the lithium metal oxide compound include: lithium cobaltate, lithium nickelate, lithium manganate, etc. As the conductive assistant, acetylene black or the like can be used. As the binder, polyvinylidene fluoride or the like can be used.
As shown in fig. 3, the positive electrode collector 11X (the 1 st electrode collector 11) has: a1 st end region a1 and a1 st electrode region b 1. The positive electrode active material layer 12X (the 1 st electrode active material layer 12) is disposed only in the 1 st electrode region b1 of the positive electrode collector 11X. The 1 st end region a1 and the 1 st electrode region b1 are arranged in the 2 nd direction d 2. The 1 st end region a1 is closer to the outer side in the 2 nd direction d2 (left side in fig. 3) than the 1 st electrode region b 1. As shown in fig. 4, the plurality of positive electrode current collectors 11X are joined and electrically connected to the 1 st end region a1 by resistance welding, ultrasonic welding, bonding with a tape, welding, or the like. In the illustrated example, one tab 4 is electrically connected to the positive electrode collector 11X in the 1 st end region a 1. The tab 4 extends from the membrane electrode assembly 5 in the 2 nd direction d 2. On the other hand, as shown in fig. 3, the 1 st electrode region b1 is located in a region facing the negative electrode active material layer 22Y of the negative electrode plate 20Y, which will be described later. As shown in fig. 5, the width of the positive electrode plate 10X in the 1 st direction d1 is smaller than the width of the negative electrode plate 20Y in the 1 st direction d 1. With the arrangement of the 1 st electrode region b1, lithium deposition from the positive electrode active material layer 12X can be prevented.
Next, the negative electrode plate 20Y (2 nd electrode plate 20) will be described. The negative electrode plate 20Y (the 2 nd electrode plate 20) has: a negative electrode current collector 21Y (the 2 nd electrode current collector 21), and a negative electrode active material layer 22Y (the 2 nd electrode active material layer 22) provided on the negative electrode current collector 21Y. In the lithium ion secondary battery, the negative electrode plate 20Y absorbs lithium ions during discharge and releases lithium ions during charge.
The negative electrode current collector 21Y has a1 st surface 21a and a 2 nd surface 21b facing each other as main surfaces. The anode active material layer 22Y is formed on both surfaces of the 1 st surface 21a and the 2 nd surface 21b of the anode current collector 21Y. The plurality of negative electrode plates 20Y included in the stacked battery 1 have a pair of negative electrode active material layers 22Y provided on both sides of the negative electrode current collector 21Y, and may have the same configuration.
The negative electrode current collector 21Y and the negative electrode active material layer 22Y can be produced by various production methods using various materials suitable for the stacked battery 1 (lithium ion secondary battery). As an example, the negative electrode collector 21Y may be formed of, for example, a copper foil. The anode active material layer 22Y includes, for example: a negative electrode active material containing a carbon material, and a binder functioning as a binder. The anode active material layer 22Y can be prepared, for example, by: a slurry for a negative electrode, which is obtained by dispersing a negative electrode active material including carbon powder, graphite powder, or the like, and a binder such as polyvinylidene fluoride in a solvent, is applied to a material to be the negative electrode current collector 21Y and cured.
As described above, the 1 st electrode region b1 of the positive electrode plate 10X is located inside the region facing the 2 nd electrode region b2 of the negative electrode plate 20Y (see fig. 3). That is, the 2 nd electrode region b2 extends in a region including a region facing the positive electrode active material layer 12X of the positive electrode plate 10X. As shown in fig. 5, the negative electrode plate 20Y has a width in the 1 st direction d1 greater than that of the positive electrode plate 10X in the 1 st direction d 1. In particular, one side end 20a of the negative electrode plate 20Y in the 1 st direction d1 is closer to one side in the 1 st direction d1 than one side end 10a of the positive electrode plate 10X in the 1 st direction d1, and the other side end 20b of the negative electrode plate 20Y in the 1 st direction d1 is closer to the other side in the 1 st direction d1 than the other side end 10b of the positive electrode plate 10X in the 1 st direction d 1.
Next, the insulating sheet 30 will be explained. As shown in fig. 4 to 7, the insulating sheet 30 is disposed between two positive electrode plates 10X (1 st electrode plate 10) and negative electrode plates 20Y (2 nd electrode plate 20) adjacent to each other in the stacking direction dL. The insulating sheet 30 insulates the adjacent two positive electrode plates 10X and negative electrode plates 20Y, and supplies the electrolyte to the positive electrode plates 10X and negative electrode plates 20Y while holding the electrolyte sealed in the exterior package 3 together with the membrane electrode assembly 5. As shown in fig. 4, the insulation sheets 30 are alternately turned back in the 1 st direction d1 (width direction) not parallel to the lamination direction dL. That is, the insulating sheet 30 is formed into a U-folded shape. One of a pair of main surfaces of the insulating sheet 30 facing each other faces the positive electrode plate 10X, and the other of the pair of main surfaces faces the negative electrode plate 20Y.
In the illustrated example, 1 insulating sheet 30 is formed in a U-folded shape and is disposed between positive electrode plate 10X and negative electrode plate 20Y. However, without being limited to this example, the stacked-type battery 1 may have a plurality of insulating sheets 30 formed in a U-folded shape. The thickness of the insulating sheet 30 is, for example, 8 μm to 30 μm.
In the example shown in fig. 5, the insulating sheet 30 includes: insulation portion 31, extension portion 32, and folded portions 33 and 34. The folded portions 33, 34 include: the 1 st folded portion 33 in which the insulation sheet 30 is folded back on one side in the 1 st direction d1, and the 2 nd folded portion 34 in which the insulation sheet 30 is folded back on the other side in the 1 st direction d 1.
Insulating portion 31 is a portion of insulating sheet 30 disposed between positive electrode plate 10X and negative electrode plate 20Y, and prevents short circuit between positive electrode plate 10X and negative electrode plate 20Y. That is, in the stacking direction dL, the insulating portion 31 is disposed between each positive electrode plate 10X and negative electrode plate 20Y. In other words, positive electrode plate 10X, insulating portion 31, negative electrode plate 20Y, insulating portion 31, and positive electrode plate 10X … are stacked in the stacking direction dL in this order. Insulating portion 31 is provided to cover the entire region of the facing portion of positive electrode plate 10X and negative electrode plate 20Y in stacking direction dL.
The protruding portion 32 is a portion of the insulation sheet 30 protruding from the insulation portion 31 at a position corresponding to the end portions of the positive electrode plate 10X and the negative electrode plate 20Y in the 1 st direction d 1. More specifically, as shown in fig. 6 and 7 in which a part of one side and the other side of the 1 st direction d1 of the membrane electrode assembly 5 shown in fig. 5 is enlarged, the extension portion 32 is: a portion of the insulating sheet 30 on one side of the 1 st direction d1 closer to the 1 st direction d1 than the one side end 10a of the end of the positive electrode plate 10X and the one side end 20a of the end of the negative electrode plate 20Y, and a portion on the other side of the 1 st direction d1 than the other side end 10b of the end of the positive electrode plate 10X and the other side end 20b of the end of the negative electrode plate 20Y, are closer to the 1 st direction d 1. The length of each extension 32 in the 1 st direction d1 is, for example, 0.5mm to 3.0 mm.
The 1 st folded portion 33 and the 2 nd folded portion 34 are parts of the insulating sheet 30 for folding the insulating sheet 30 in a U-folded shape. As shown in fig. 6, the 1 st folded portion 33 is closer to the 1 st direction d1 than the one-side end 10a of the positive electrode plate 10X. The 1 st folded portion 33 faces the one end 10a of the positive electrode plate 10X in the 1 st direction d 1. Similarly, as shown in fig. 7, the 2 nd folded portion 34 is closer to the other side in the 1 st direction d1 than the other end portion 20b of the negative electrode plate 20Y. The 2 nd folded portion 34 faces the other end 20b of the negative electrode plate 20Y in the 1 st direction d 1. As shown in fig. 5 to 7, the 1 st folded portion 33 and the 2 nd folded portion 34 may be in contact with the exterior package 3.
In the example shown in fig. 6 and 7, since the insulation sheet 30 includes the protruding portion 32, the gap 40 is provided between the 1 st folded portion 33 and the one-side end portion 10a of the positive electrode plate 10X facing the 1 st folded portion 33 in the 1 st direction d 1. Similarly, since the insulating sheet 30 includes the projecting portion 32, a gap 40 is provided between the 2 nd folded portion 34 and the other end portion 20b of the negative electrode plate 20Y facing the 2 nd folded portion 34 in the 1 st direction d 1. Of the dimensions of the gap 40, the length of the 1 st folded portion 33 protruding from the one end 10a of the positive electrode plate 10X, which is the length S1 between the 1 st folded portion 33 and the one end 10a of the positive electrode plate 10X shown in fig. 6, is preferably 5 times or more, more preferably 10 times or more, the thickness T1 of the positive electrode plate 10X provided with the gap 40, which is equivalent to the length obtained by adding the thickness of the insulating sheet at the 1 st folded portion 33. Similarly, of the dimensions of the gap 40, the length of the 2 nd folded portion 34 protruding from the other end 20b of the negative electrode plate 20Y, which is the length S2 between the 2 nd folded portion 34 and the other end 20b of the negative electrode plate 20Y shown in fig. 7, is preferably 5 times or more, more preferably 10 times or more, the thickness T2 of the negative electrode plate 20Y provided with the gap 40, the length corresponding to the length obtained by adding the thickness of the insulating sheet at the 2 nd folded portion 34.
Fig. 8 is an enlarged view of the frame VIII shown in fig. 3. In fig. 8, a part of the end of the insulating sheet 30 is enlarged. In the example shown in fig. 8, irregular irregularities are formed in the projecting portion 32 and the 2 nd folded portion 34 of the insulating sheet 30. Although not shown, irregular asperities are similarly formed in the 1 st folded portion 33.
The unevenness is formed by a corrugated portion generated in the insulating sheet 30. Therefore, the unevenness includes: a portion indicated as a convex portion 37 on one surface and a concave portion 38 on the other surface of the insulating sheet 30, a portion indicated as a concave portion 38 on one surface and a convex portion 37 on the other surface of the insulating sheet 30. In addition, in the 1 st folded portion 33 and the extension portion 32 connected to the 1 st folded portion 33, the convex portion 37 and the concave portion 38 are formed on the surface facing the positive electrode plate 10X. Moreover, the convex portion 37 protrudes toward the positive electrode plate 10X, so that the electrolyte held by the insulating sheet 30 can be stably supplied from the convex portion 37 to the positive electrode plate 10X. Similarly, in the 2 nd folded portion 34 and the extension portion 32 connected to the 2 nd folded portion 34, a convex portion 37 and a concave portion 38 are formed on a surface facing the negative electrode plate 20Y. The convex portion 37 protrudes toward the negative electrode plate 20Y, so that the electrolyte held in the insulating sheet 30 can be stably supplied from the convex portion 37 to the negative electrode plate 20Y.
The convex portion 37 and the concave portion 38 are formed in a linear shape, for example, and extend along one surface of the insulating sheet 30. In the example shown in fig. 8, the convex and concave portions are arranged in the 2 nd direction d 2. In this example, the convex portion 37 and the concave portion 38 extend in a direction not parallel to the 2 nd direction d2, for example, the 1 st direction d 1.
In the example shown in fig. 6, the 1 st folded portion 33 is closer to the 1 st direction d1 than the one-side end 20a of the negative electrode plate 20Y adjacent to the positive electrode plate 10X facing the 1 st folded portion 33 in the lamination direction dL. That is, the extending portion 32 of the insulating sheet 30 extends from the 1 st direction d1 side with respect to the positive electrode plate 10X and the negative electrode plate 20Y. As described above, the negative electrode plate 20Y extends further than the positive electrode plate 10X on both sides in the 1 st direction d1, and therefore, as shown in fig. 7, the 2 nd folded portion 34 is located further to the other side in the 1 st direction d1 than the other side end 10b of the positive electrode plate 10X adjacent to the negative electrode plate 20Y facing the 2 nd folded portion 34 in the stacking direction dL.
Fig. 6 and 7 show an example in which the length of the projecting portion 32 in one side and the length of the other side in the 1 st direction d1 are equal. That is, the length S1 in the 1 st direction d1 between the 1 st folded portion 33 and the one end 10a of the positive electrode plate 10X facing the 1 st folded portion 33, and the length S2 in the 1 st direction d1 between the 2 nd folded portion 34 and the other end 20b of the negative electrode plate 20Y facing the 2 nd folded portion 34 are equal. With this configuration, a sufficient amount of electrolyte absorbed and held by the insulating sheet 30 can be efficiently supplied to both the region near the one end 10a of the positive electrode plate 10X covered by the 1 st folded portion 33 in the 1 st direction and the region near the other end 20b of the negative electrode plate 20Y covered by the 2 nd folded portion 34 in the 1 st direction.
As described above, negative electrode plate 20Y extends further than positive electrode plate 10X on both sides in direction 1 d 1. That is, the length S1 in the 1 st direction d1 between the 1 st folded portion 33 and the one-side end portion 10a of the positive electrode plate 10X facing the 1 st folded portion 33 is greater than the length S3 in the 1 st direction d1 between the 1 st folded portion 33 and the one-side end portion 20a of the negative electrode plate 20Y adjacent to the positive electrode plate 10X facing the 1 st folded portion in the stacking direction dL. Therefore, a length S3 in the 1 st direction d1 between the 1 st folded portion 33 and one end 20a of the negative electrode plate 20Y adjacent to the positive electrode plate 10X facing the 1 st folded portion in the stacking direction dL is smaller than a length S2 in the 1 st direction d1 between the 2 nd folded portion 34 and the other end 20b of the negative electrode plate 20Y facing the 2 nd folded portion 34.
As shown in fig. 4, 6, and 7, the insulating sheet 30 includes: a base material layer 35, and a functional layer 36 laminated on the base material layer 35. In the illustrated example, the side of the insulating sheet 30 on which the substrate layer 35 is provided faces the positive electrode plate 10X, and the side on which the functional layer 36 is provided faces the negative electrode plate 20Y. However, the present invention is not limited to the illustrated example, and the side provided with the base layer 35 may face the negative electrode plate 20Y and the side provided with the functional layer 36 may face the positive electrode plate 10X.
The base layer 35 is formed of, for example, a porous body. Examples of such porous bodies include porous films made of resins such as polyethylene and polypropylene. The thickness of the base material layer 35 is, for example, 5 μm or more and 30 μm or less.
The functional layer 36 contains, for example, an inorganic material. Such a functional layer 36 is, for example, a layer containing alumina particles. By including the functional layer 36 with an inorganic material, the heat resistance of the functional layer 36 can be improved. The layer containing an inorganic material such as alumina particles is less likely to thermally shrink when heated than an organic material such as a resin forming the base layer 35. That is, by providing the functional layer 36 to the insulating sheet 30, the degree of thermal shrinkage of the insulating sheet 30 is reduced. Thus, for example, even when the battery is left in a high-temperature environment, the risk that the insulating sheet 30 contracts and the positive and negative electrodes come into contact with each other and a short circuit occurs can be reduced. The thickness of the functional layer 36 is, for example, 2 μm to 15 μm.
Here, in the stacked battery, the electrolyte solution held in the insulating sheet is present inside the outer package, more specifically, between the positive electrode plate and the negative electrode plate. The discharge and charge of the stacked type battery are performed by: the positive electrode plate and the negative electrode plate emit and absorb ions through the electrolyte. In other words, the positive electrode plate and the negative electrode plate facing the portion of the insulating sheet holding the electrolyte solution function as a battery by supplying the electrolyte solution from the insulating sheet. On the other hand, the positive electrode plate and the negative electrode plate facing the portion of the insulating sheet not holding the electrolyte cannot be supplied with the electrolyte, and therefore cannot release or absorb ions, and cannot function as a battery. Therefore, in the case of the insulating sheet, it is desirable to hold the electrolytic solution throughout the portion facing the positive electrode plate and the negative electrode plate.
However, in the conventional stacked cell shown in JP2014-165055a, the insulating sheet is folded in a U-shape. The present inventors confirmed that the folding back occurred, and thus the porosity in the vicinity of the folded back portion of the insulating sheet was low, and it was difficult to hold the electrolyte. Therefore, the electrolyte is difficult to be supplied to the vicinity of the end portions of the positive and negative electrode plates facing the folded portion of the insulating sheet, and it is difficult to contribute to charging and discharging. Therefore, in the conventional stacked battery having the insulating sheet in the U-folded shape, the charging and discharging efficiency may be deteriorated.
On the other hand, in the stacked-type battery according to claim 1, even when the insulating sheet is U-folded, the insulating sheet can sufficiently hold the electrolyte solution in the portion facing the positive electrode plate and the negative electrode plate in the vicinity of the end portions thereof. Therefore, the electrolyte can be sufficiently supplied to the vicinity of the end portions of the positive electrode plate and the negative electrode plate facing the folded portion of the insulating sheet, and deterioration in the efficiency of charge and discharge of the stacked battery can be suppressed. In other words, the efficiency of charging and discharging the stacked battery can be improved. Hereinafter, in the stacked-type battery 1 according to embodiment 1, the insulating sheet 30 is described as being capable of holding the electrolyte in the portion facing the vicinity of the end portions of the positive electrode plate 10X and the negative electrode plate 20Y.
In the stacked-type battery 1 according to embodiment 1, a gap 40 is provided between the 1 st folded portion 33 of the insulating sheet 30 and the one-side end portion 10a of the positive electrode plate 10X facing the 1 st folded portion 33 in the 1 st direction d 1. Similarly, a gap 40 is provided between the 2 nd folded portion 34 and the other end 20b of the negative electrode plate 20Y facing the 2 nd folded portion 34 in the 1 st direction d 1. The insulating sheet 30 has a portion projecting to the 1 st direction d1 side from the one end 10a of the positive electrode plate 10X, that is, a projecting portion 32, so that the gap 40 is provided. Further, the insulating sheet 30 has a portion projecting to the other side in the 1 st direction d1 from the other side end portion 20b of the negative electrode plate 20Y, that is, a projecting portion 32, so that the gap 40 is provided. The protruding portion 32 of the insulating sheet 30 can hold the electrolyte. The extension 32, which is a portion where the vicinity of the one end 10a of the positive electrode plate 10X and the vicinity of the other end 20b of the negative electrode plate 20Y face each other, can hold the electrolyte, and therefore the electrolyte can be supplied to the vicinity of the one end 10a of the positive electrode plate 10X and the vicinity of the other end 20b of the negative electrode plate 20Y. Therefore, it is possible to contribute to charge and discharge in the vicinity of one end 10a of the positive electrode plate 10X and in the vicinity of the other end 20b of the negative electrode plate 20Y, and to improve the efficiency of charge and discharge of the stacked battery.
The size of the gap 40 in the 1 st direction d1, i.e., the length S1 between the 1 st folded portion 33 and the one end 10a of the positive electrode plate 10X is preferably 5 times or more or 10 times or more the thickness T1 of the positive electrode plate 10X provided with the gap 40. The length S2 between the 2 nd folded portion 34 and the other end 20b of the negative electrode plate 20Y is 5 times or more or 10 times or more the thickness T2 of the negative electrode plate 20Y provided with the gap 40. In these cases, the protruding portion 32 has a sufficient size, and therefore the protruding portion 32 can hold a sufficient amount of the electrolytic solution. That is, the portion of the insulating sheet 30 facing the vicinity of the one end 10a of the positive electrode plate 10X and the vicinity of the other end 20b of the negative electrode plate 20Y can sufficiently hold the electrolyte, and the electrolyte can be sufficiently supplied to the vicinity of the one end 10a of the positive electrode plate 10X and the vicinity of the other end 20b of the negative electrode plate 20Y. Therefore, sufficient charge and discharge can be facilitated in the vicinity of one side end 10a of the positive electrode plate 10X and the vicinity of the other side end 20b of the negative electrode plate 20Y, and the efficiency of charge and discharge of the stacked type battery can be further improved.
The stacked battery 1 includes tens of positive electrode plates 10X and tens of negative electrode plates 20Y. The vicinity of the end portions of each of the positive electrode plate 10X and the negative electrode plate 20Y does not contribute to charging and discharging, and the efficiency of charging and discharging of the entire stacked battery 1 is significantly deteriorated. Therefore, the larger the number of positive electrode plates 10X and negative electrode plates 20Y, the more significant the effect of improving the charge and discharge efficiency by providing the gaps 40. Specifically, when the stacked battery 1 includes 20 or more positive electrode plates 10X and negative electrode plates 20Y in total, the effect of improving the charge and discharge efficiency is significant.
Further, the 1 st folded portion 33 is closer to the 1 st direction d1 than the one-side end portion 20a in the 1 st direction d1 of the negative electrode plate 20Y adjacent to the positive electrode plate 10X facing the 1 st folded portion 33 in the stacking direction dL. That is, the extension portion 32 extends to the 1 st direction d1 side with respect to the negative electrode plate 20Y. The projecting portion 32 facing the vicinity of the one end 20a of the negative electrode plate 20Y holds the electrolyte, and therefore the electrolyte can be supplied to the vicinity of the one end 20a of the negative electrode plate 20Y. Therefore, it is possible to contribute to charge and discharge in the vicinity of one side end portion 20a of the negative electrode plate 20Y, and it is possible to further improve the efficiency of charge and discharge of the stacked-type battery.
Similarly, the second folded portion 34 is located on the other side in the 1 st direction d1 from the other end 10b of the positive electrode plate 10X adjacent to the negative electrode plate 20Y facing the second folded portion 34. That is, the protruding portion 32 protrudes to the other side of the 1 st direction d1 than the positive electrode plate 10X. The extending portion 32 facing the other end 10b of the positive electrode plate 10X holds the electrolyte, and therefore the electrolyte can be supplied to the vicinity of the other end 10b of the positive electrode plate 10X. Therefore, it is possible to contribute to the charge and discharge in the vicinity of the other-side end 10b of the positive electrode plate 10X, and it is possible to further improve the efficiency of the charge and discharge of the stacked-type battery.
Irregular asperities are formed in the projecting portions 32, the 1 st folded portion 33, and the 2 nd folded portion 34, which are both end portions of the insulating sheet 30. In other words, the insulating sheet 30 is formed with wrinkles at both side ends in the 1 st direction d 1. The surface area of the insulating sheet 30 in the projecting portion 32, the 1 st folded portion 33, and the 2 nd folded portion 34 is increased by irregular unevenness (wrinkles). The projecting portion 32, the 1 st folded portion 33, and the 2 nd folded portion 34 of the insulating sheet 30 have an increased area in contact with the electrolyte sealed in the housing space formed by the exterior package 3. The amount of the electrolyte supplied to the insulating sheet 30 increases as the area in contact with the electrolyte increases. Therefore, the electrolyte is easily held in the projecting portion 32, the 1 st folded portion 33, and the 2 nd folded portion 34 of the insulation sheet 30. Since the electrolyte can be held in the portion where the vicinity of one end 10a of positive electrode plate 10X and the vicinity of the other end 20b of negative electrode plate 20Y face each other, the electrolyte can be supplied to the vicinity of one end 10a of positive electrode plate 10X and the vicinity of the other end 20b of negative electrode plate 20Y. Therefore, it is possible to contribute to charge and discharge in the vicinity of one side end 10a of the positive electrode plate 10X and in the vicinity of the other side end 20b of the negative electrode plate 20Y, and it is possible to improve the charge and discharge efficiency of the stacked type battery.
Irregular irregularities (wrinkles) in the extending portion 32, the 1 st folded portion 33, and the 2 nd folded portion 34 of the insulating sheet 30 are easily formed when the base material layer 35 constituting the insulating sheet 30 is formed of a porous body. In particular, when a resin porous film (a porous body of a polyolefin polymer such as polypropylene or polyethylene) is used as the insulating sheet 30, irregularities (wrinkles) that facilitate the above-described effects are easily formed.
Further, the insulating sheet 30 preferably has: a functional layer 36 comprising an inorganic material. The functional layer 36 containing an inorganic material has a high porosity, and thus can hold a larger amount of the electrolytic solution. Therefore, the insulating sheet 30 can sufficiently hold the electrolytic solution, and can contribute to charge and discharge with good efficiency to the positive electrode plate 10X and the negative electrode plate 20Y. That is, the charge and discharge efficiency of the stacked battery can be improved.
Negative electrode plate 20Y is longer than positive electrode plate 10X in direction 1 d1, and therefore negative electrode plate 20Y is less likely to face the portion holding the electrolyte. Here, the insulating sheet 30 is preferably disposed so that the side of the insulating sheet 30 on which the functional layer 36 is provided faces the negative electrode plate 20Y. When the side on which the electrolyte is sufficiently held faces negative electrode plate 20Y, the electrolyte can be sufficiently supplied to negative electrode plate 20Y. Therefore, the negative electrode plate 20Y can contribute to charge and discharge efficiently, and the charge and discharge efficiency of the stacked battery can be improved.
Further, the side of positive electrode plate 10X is more likely to become high temperature than the side of negative electrode plate 20Y. When one side of the positive electrode plate 10X faces, for example, the substrate layer 35 including polyethylene, the polyethylene is exposed to high temperature and may be polyalkylenated. When the polyethylene is polyalkylenated, the insulating property of the base layer 35 is lost. Here, the layer of the insulating sheet 30 facing the one side surface of the positive electrode plate 10X preferably has heat resistance. Here, the functional layer 36 including an inorganic material is excellent in heat resistance. That is, the functional layer 36 is not easily deteriorated even when exposed to high temperature. Therefore, when the insulating sheet 30 is disposed so that the side of the insulating sheet 30 on which the functional layer 36 is provided faces the side of the positive electrode plate 10X which is likely to become high in temperature, the insulating property of the insulating sheet 30 can be maintained even when the temperature of the positive electrode plate 10X becomes high.
Further, a length S3 in the 1 st direction d1 between the 1 st folded portion 33 and one side end portion 20a of the negative electrode plate 20Y adjacent to the positive electrode plate 10X facing the 1 st folded portion 33 in the lamination direction dL is smaller than a length S2 in the 1 st direction d1 between the 2 nd folded portion 34 and the other side end portion 20b of the negative electrode plate 20Y facing the 2 nd folded portion 34. In the side of the 1 st direction d1, the protruding portion 32 has a length that is necessary and sufficient for supplying the electrolyte to the positive electrode plate 10X and for efficiently contributing to charging and discharging with respect to the positive electrode plate 10X, and is not unnecessarily long. That is, the overall size of the stacked battery 1 can be made more compact. The positive electrode plate 10X and the negative electrode plate 20Y can efficiently contribute to charge and discharge, and the volume of the stacked battery 1 can be reduced, so that the battery capacity (energy density) per unit volume can be increased.
In addition, in a state where the exterior package 3 houses the membrane electrode assembly 5, the 1 st folded portion 33 and the 2 nd folded portion 34 are in contact with the exterior package 3. In other words, the exterior package 3 is sized so that the length of the defined housing portion of the exterior package 3 in the 1 st direction d1 coincides with the length of the membrane electrode assembly 5. In this case, the size of the exterior package 3 does not become unnecessarily long. That is, the overall size of the stacked battery 1 can be made compact. Therefore, the battery capacity (energy density) per unit volume of the stacked battery 1 can be increased.
Next, a method for manufacturing the stacked-type battery 1 according to embodiment 1 configured as a lithium-ion secondary battery will be described. A method for manufacturing a stacked battery 1 described below includes: a step of preparing a positive electrode plate 10X (1 st electrode plate 10), a negative electrode plate 20Y (2 nd electrode plate 20), and an insulating sheet 30; and a step of folding back the insulation sheet 30 in a U-folded shape and alternately stacking the insulation sheet through the positive electrode plate 10X (1 st electrode plate 10) and the negative electrode plate 20Y (2 nd electrode plate 20).
First, a process of preparing each of the positive electrode plate 10X (1 st electrode plate 10), the negative electrode plate 20Y (2 nd electrode plate 20), and the insulating sheet 30 will be described. The positive electrode plate 10X, the negative electrode plate 20Y, and the insulating sheet 30 may be prepared at different timings through different processes. In addition, the positive electrode plate 10X, the negative electrode plate 20Y, and the insulating sheet 30 may be simultaneously and collectively prepared, and the prepared positive electrode plate 10X and negative electrode plate 20Y may be sequentially supplied to: and a step of folding and folding the insulating sheet 30 in a U-shape and alternately stacking the insulating sheet through the positive electrode plates 10X (1 st electrode plate 10) and the negative electrode plates 20Y (2 nd electrode plate 20).
The positive electrode plate 10X can be prepared, for example, in the following manner: a composition (slurry) for constituting the positive electrode active material layer 12X is applied and cured on a long aluminum foil for constituting the positive electrode current collector 11X, and then cut into a desired size. Also, negative electrode plate 20Y can be produced, for example, by: the composition (slurry) for constituting the negative electrode active material layer 22Y is applied and cured on the long copper foil for constituting the negative electrode current collector 21Y, and then cut into a desired size. The insulating sheet 30 can be formed by, for example, applying a functional layer 36 containing an inorganic material on a base layer 35 formed of a porous body, and cut to a desired size.
Next, a process of folding and folding the insulation sheet 30 in a U-shape and alternately stacking the insulation sheet through the positive electrode plate 10X (1 st electrode plate 10) and the negative electrode plate 20Y (2 nd electrode plate 20) will be described. This step can be performed using, for example, an apparatus described in JP2014-165055 a. That is, insulating sheets 30 are alternately folded back, and positive electrode plates 10X and negative electrode plates 20Y are alternately supplied onto the folded-back insulating sheets 30 each time insulating sheets 30 are folded back. However, unlike the process described in JP2014-165055a, the insulating sheet 30 is folded back such that the gap 40 is provided between the 1 st folded back portion 33 of the insulating sheet 30 and the one side end portion 10a of the positive electrode plate 10X facing the 1 st folded back portion 33 in the 1 st direction d1, and between the 2 nd folded back portion 34 and the other side end portion 20b of the negative electrode plate 20Y facing the 2 nd folded back portion 34 in the 1 st direction d 1. In other words, the insulation sheet 30 is folded so as to form the 1 st folded portion 33 on one side of the one end portion 10a of the positive electrode plate 10X, and is folded so as to form the 2 nd folded portion 34 on the other side of the other end portion 20b of the negative electrode plate 20Y. That is, the insulating sheet 30 is folded back to form the protruding portion 32.
In this step, positive electrode plate 10X and negative electrode plate 20Y are stacked such that positive electrode active material layer 12X of positive electrode plate 10X and negative electrode active material layer 22Y of negative electrode plate 20Y face each other. When the positive electrode active material layer 12X and the negative electrode active material layer 22Y are not directly opposed to each other between the positive electrode plate 10X and the negative electrode plate 20Y, the effective areas of the positive electrode plate 10X and the negative electrode plate 20Y are reduced, and a predetermined capacity cannot be obtained, and there is a possibility that the positive electrode plate 10X and the negative electrode plate 20Y are short-circuited and a spark is generated. In the stacked battery 1 configured as a lithium ion secondary battery, when the positive electrode plate 10X is not aligned with the negative electrode plate 20Y, the following results: lithium precipitates are generated, and damage is caused to the membrane electrode assembly 5 and the exterior package 3.
In the above-described manner, after the insulating sheet 30 is folded in a U-shape and alternately stacked via the positive electrode plates 10X (1 st electrode plate 10) and the negative electrode plates 20Y (2 nd electrode plate 20), the plurality of positive electrode plates 10X are joined to each other at one end portion in the 2 nd direction d2 and are electrically connected. The tab 4 is electrically connected to one end in the 2 nd direction d 2. Also, the plurality of negative electrode plates 20Y are joined to each other and conducted in the end portion of the other side of the 2 nd direction d 2. The tab 4 is electrically connected to the other end in the 2 nd direction d 2.
Then, the membrane electrode assembly 5 is sealed in the exterior package 3 together with the electrolyte solution so that each tab 4 protrudes from the exterior package 3, thereby obtaining the stacked cell 1. The membrane electrode assembly 5 is housed in the exterior package 3 such that the 1 st folded portion 33 and the 2 nd folded portion 34 of the insulation sheet 30 are in contact with the exterior package 3.
The material of the insulating sheet 30, the amount of the electrolyte sealed into the exterior package 3, the internal pressure of the exterior package 3, and the like are appropriately adjusted and combined within the range selected for the conventional stacked battery, whereby the projections and depressions shown in fig. 8 can be formed in the extending portions 32 and the folded portions 33 and 34 of the insulating sheet 30. The insulating sheet 30 can be easily formed with irregularities by selecting a resin porous film using a flexible porous body, for example, a polyolefin polymer such as polypropylene or polyethylene, as the base layer 35. The degree of the insulating sheet 30 is affected by the amount of the electrolyte. By setting the internal pressure of the exterior package 3 to a negative pressure, the insulating portion 31 of the insulating sheet 30 is compressed to some extent, and the extending portion 32 and the folded portions 33 and 34 absorb the electrolyte more easily than the insulating portion 31. This makes the protruding portion 32 and the folded portions 33 and 34 more likely to swell than the insulating portion 31, and in this case, local unevenness in the protruding portion 32 and the folded portions 33 and 34 can be promoted.
As described above, the stacked-type battery 1 according to embodiment 1 includes: a plurality of electrode plates 10, 20 laminated in a lamination direction dL; and an insulating sheet 30 that is alternately folded back in a width direction (1 st direction d1) that is not parallel to the stacking direction dL and is disposed between two electrode plates 10, 20 adjacent in the stacking direction dL, wherein a gap 40 is provided between the folded- back portions 33, 34 of the insulating sheet 30 and the end portions 10a, 20b of the electrode plates 10, 20 that face the folded- back portions 33, 34 in the width direction. In the stacked battery 1, the electrolyte can be held in the portions of the electrode plates 10 and 20 near the ends 10a and 20b facing each other, and therefore the electrolyte can be supplied to the portions of the electrode plates 10 and 20 near the ends 10a and 20b, which contributes to charging and discharging. Therefore, in the stacked type battery 1 having the insulating sheet 30 in the U-folded shape, the charging and discharging efficiency can be improved.
In the stacked cell 1 of embodiment 1, the lengths S1, S2 in the width direction between the folded portions 33, 34 and the end portions 10a, 20b of the electrode plates 10, 20 facing the folded portions 33, 34 are 5 times or more or 10 times or more the thicknesses T1, T2 of the electrode plates 10, 20. With such a stacked-type battery 1, the electrolyte can be sufficiently retained in the portion where the vicinity of the end 10a of the positive electrode plate 10X and the vicinity of the end 20b of the negative electrode plate 20Y face each other. Therefore, the electrolyte can be sufficiently supplied to the vicinity of end 10a of positive electrode plate 10X and the vicinity of end 20b of negative electrode plate 20Y, and charging and discharging can be sufficiently facilitated. That is, the efficiency of charging and discharging the stacked battery can be further improved.
In the stacked-layer battery 1 according to embodiment 1, the folded portions 33 and 34 have irregularities. In the stacked battery 1, the surface area of the insulating sheet 30 is increased in the folded portions 33 and 34, and the area in contact with the electrolyte solution is increased. Therefore, the electrolyte solution is easily held in the vicinity of the folded portions 33 and 34 of the insulating sheet 30. Therefore, the electrolyte can be held in the portion where the vicinity of the end 10a of the positive electrode plate 10X and the vicinity of the end 20b of the negative electrode plate 20Y face each other, and therefore the electrolyte can be supplied to the vicinity of the end 10a of the positive electrode plate 10X and the vicinity of the end 20b of the negative electrode plate 20Y, which contributes to charging and discharging. That is, the charge and discharge efficiency of the stacked battery can be improved.
In the stacked-layer battery 1 according to embodiment 1, the insulating sheet 30 has a base layer 35 formed of a porous body. Since the porous body has flexibility, the recesses and projections are easily formed in the folded portions 33 and 34 of the insulating sheet 30 in the stacked battery 1. Therefore, the effect of improving the charge and discharge efficiency of the stacked battery is easily achieved.
In the stacked-type battery 1 according to embodiment 1, the insulating sheet 30 has the functional layer 36 containing an inorganic material. With such a stacked-type battery 1, the insulating sheet 30 is made to easily hold the electrolytic solution, and thus can contribute to charge and discharge of the positive electrode plate 10X and the negative electrode plate 20Y with good efficiency. Therefore, the charge and discharge efficiency of the stacked battery can be improved.
In the stacked-type battery 1 according to embodiment 1, the plurality of electrode plates 10 and 20 include: the 1 st electrode plate 10 and the 2 nd electrode plate 20 having a length in the width direction larger than that of the 1 st electrode plate 10 are alternately stacked in the stacking direction dL, and the folded portions 33, 34 include: a1 st folded portion 33 in which the insulation sheet 30 is folded back on one side in the width direction; the 2 nd folded portion 34 in which the other side of the insulating sheet 30 in the width direction is folded, the 1 st folded portion 33 is located on one side in the width direction of the end 20a on one side in the width direction of the 2 nd electrode plate 20 adjacent to the 1 st electrode plate 10 facing the 1 st folded portion 33. In the stacked battery 1, since the electrolyte is retained in the portion of the insulating sheet 30 facing the vicinity of the end 20a on the one side of the negative electrode plate 20Y, the electrolyte can be supplied to the vicinity of the end 20a on the one side of the negative electrode plate 20Y, which contributes to charging and discharging, and the efficiency of charging and discharging of the stacked battery can be further improved.
In the stacked-type battery 1 according to embodiment 1, the plurality of electrode plates 10 and 20 include: the 1 st electrode plate 10 and the 2 nd electrode plate 20 having a length in the width direction larger than that of the 1 st electrode plate 10 are alternately stacked in the stacking direction dL, and the folded portions 33, 34 include: a1 st folded portion 33 in which the insulation sheet 30 is folded back on one side in the width direction; the 2 nd folded portion 34 of the insulating sheet 30 folded back on the other side in the width direction, and the length S3 in the width direction between the 1 st folded portion 33 and the end 20a on one side in the width direction of the 2 nd electrode plate 20 adjacent to the 1 st electrode plate 10 facing the 1 st folded portion 33 is smaller than the length in the width direction between the 2 nd folded portion 34 and the end 20b on the other side in the width direction of the 2 nd electrode plate 20 facing the 2 nd folded portion 34. With such a stacked cell 1, the overall size of the stacked cell 1 can be made compact, charging and discharging can be efficiently facilitated for the positive electrode plates 10X and the negative electrode plates 20Y, and the volume of the stacked cell 1 can be reduced, so the cell capacity (energy density) per unit volume can be increased.
In the stacked-type battery 1 according to embodiment 1, the plurality of electrode plates 10 and 20 include: the 1 st electrode plate 10 and the 2 nd electrode plate 20 having a length in the width direction larger than the 1 st electrode plate 10 are alternately stacked in the stacking direction dL, and the insulating sheet 30 has: the insulating sheet 30 includes a base material layer 35 and a functional layer 36 laminated on the base material layer 35 and having a higher porosity than the base material layer 35, wherein the side provided with the base material layer 35 faces the 1 st electrode plate 10, and the side provided with the functional layer 36 faces the 2 nd electrode plate 20. With such a stacked-type battery 1, more of the side of the insulating sheet 30 holding the electrolyte is made to face the wide negative electrode plate 20Y, so that the electrolyte can be sufficiently supplied to the negative electrode plate 20Y and charging and discharging can be efficiently facilitated.
In the stacked-type battery 1 according to embodiment 1, the plurality of electrode plates 10 and 20 include: the 1 st electrode plate 10 and the 2 nd electrode plate 20 having a length in the width direction larger than the 1 st electrode plate 10 are alternately stacked in the stacking direction dL, and the insulating sheet 30 has: the insulating sheet 30 includes a base material layer 35 and a functional layer 36 laminated on the base material layer 35 and having higher heat resistance than the base material layer 35, and the insulating sheet 30 has a side on which the base material layer 35 is provided facing the 2 nd electrode plate 20 and a side on which the functional layer 36 is provided facing the 1 st electrode plate 10. In the stacked battery 1, the insulating sheet 30 is disposed so that the side of the insulating sheet 30 on which the functional layer 36 is provided faces the side of the positive electrode plate 10X which is likely to become high in temperature, and the functional layer 36 is not changed in quality even when the temperature of the positive electrode plate 10X becomes high, thereby maintaining the insulating property of the insulating sheet 30.
The stacked-layer battery 1 according to embodiment 1 further includes: and an exterior package 3 for housing the electrode plates 10 and 20 and the insulating sheet 30, wherein the folded portions 33 and 34 are in contact with the exterior package 3. With such a stacked cell 1, the overall size of the stacked cell 1 can be made compact, and the cell capacity (energy density) per unit volume of the stacked cell 1 can be increased.
The stacked-type battery 1 according to embodiment 1 includes 20 or more electrode plates 10 and 20 in total. The stacked battery 1 can significantly improve the effect of improving the charge and discharge efficiency by providing the gap 40.
Hereinabove, the 1 st embodiment is described with reference to specific examples, but the 1 st embodiment is not intended to be limited to the specific examples described above. Embodiment 1 can be implemented by other various specific examples, and various omissions, substitutions, and changes can be made without departing from the spirit and scope thereof.
For example, in embodiment 1, the insulating sheet 30 includes: substrate layer 35, functional layer 36. However, the insulating sheet 30 may not have the functional layer 36. Such an insulating sheet 30 is more flexible than an insulating sheet having the functional layer 36, and therefore is easily deformed. Therefore, irregular unevenness (wrinkles) is easily formed at both end portions of the insulation sheet 30, i.e., the projecting portion 32, the 1 st folded portion 33, and the 2 nd folded portion 34. As described above, the surface area of the insulating sheet 30 is increased in the projecting portion 32, the 1 st folded portion 33, and the 2 nd folded portion 34 by irregular unevenness (wrinkles). The area of contact of the projecting portion 32, the 1 st folded portion 33, and the 2 nd folded portion 34 of the insulating sheet 30 with the electrolyte sealed in the housing space formed by the exterior package 3 is increased. The amount of the electrolytic solution supplied to the insulating sheet 30 increases as the area in contact with the electrolytic solution increases. Therefore, the portion where the vicinity of end 10a of positive electrode plate 10X and the vicinity of end 20b of negative electrode plate 20Y face each other is made to easily hold the electrolytic solution. Therefore, the electrolyte can be supplied to the vicinity of one end 10a of positive electrode plate 10X and the vicinity of the other end 20b of negative electrode plate 20Y. Charging and discharging can be further facilitated in the vicinity of the end 10a of the positive electrode plate 10X and in the vicinity of the end 20b of the negative electrode plate 20Y, and the efficiency of charging and discharging of the stacked battery can be further improved.
< embodiment 2 >
Fig. 9 to 16 are views for explaining embodiment 2 of the multilayer electrode according to claim 2.
In embodiment 2 described below, the stacked cell 101 includes: an exterior package 140, a membrane electrode assembly 105 housed in the exterior package 140, and a tab 103 connected to the membrane electrode assembly 105 and protruding from the inside to the outside of the exterior package 140. The membrane electrode assembly 105 has: the 1 st electrode plate 110 and the 2 nd electrode plate 120 are alternately stacked, and the insulator 130 is positioned between the 1 st electrode plate 110 and the 2 nd electrode plate 120. In the stacked cell 101, when the plurality of electrode plates 110 and 120 constituting the membrane electrode assembly 105 are manufactured, the electrode plates 110 and 120 and the exterior package 140 are short-circuited due to a decrease in positioning accuracy or a positional shift of the electrode plates 110 and 120 during use. The stacked battery 101 in which the electrode plates 110 and 120 and the exterior package 140 are short-circuited cannot perform a predetermined function. On the other hand, the stacked-type battery 101 of embodiment 2 is devised to prevent the contact between the electrode plates 110 and 120 and the exterior package 140 as described below, and has excellent reliability.
Hereinafter, an example in which the stacked cell 101 constitutes a lithium ion secondary battery will be described. In this example, the 1 st electrode plate 110 constitutes a positive electrode plate 110X, and the 2 nd electrode plate 120 constitutes a negative electrode plate 120Y. However, as will be apparent from the description of the operational effects described below, embodiment 2 described herein is not limited to a lithium ion secondary battery, and can be widely used for a stacked battery 101 in which the 1 st electrode plate 110 and the 2 nd electrode plate 120 are alternately stacked.
First, the structure of the stacked battery 101 will be described. The exterior package 140 is a packaging material for sealing the film electrode assembly 105. The exterior package 140 includes: a body 140a, and a coating layer 140b laminated on the body 140a (see fig. 14 to 16). The main body 140a preferably has high gas barrier properties and moldability. As materials for the main body 140a, there can be used: aluminum, aluminum alloys, stainless steel, and the like. The coating layer 140b has an insulating property, and prevents the electrode plates 110 and 120 accommodated in the exterior body 140 and the body 140a from being short-circuited. The coating layer 140b preferably has chemical resistance, thermoplasticity (adhesiveness), and the like in addition to the insulating property. As such a coating layer 140b, there can be used: polypropylene, modified polypropylene, low density polypropylene, ionomer, ethylene vinyl acetate.
As shown in fig. 9, 13, and 14, the exterior package 140 includes: part 1 141 and part 2 142. Between the 1 st member 141 and the 2 nd member 142, a housing space of the membrane electrode assembly 105 is formed. The exterior package 140 seals the membrane electrode assembly 105 and the electrolyte solution inside. The internal pressure of the exterior package 140 in which the membrane electrode assembly 105 and the electrolyte solution are sealed may be a negative pressure, for example, 100kPa or less.
In the illustrated example, the 1 st member 141 is formed as a plate-like member. On the other hand, the 2 nd member 142 is formed in a cup shape. The 2 nd member 142 has: a cup-shaped bulging portion 143, and a flange portion 144 connected to the bulging portion 143. The flange portion 144 surrounds the expanded portion 143 in a ring shape, and is connected to the periphery of the flange portion 144. The flange portion 144 is engaged with the 1 st member 141 in such a manner as to seal the accommodation space between the 1 st member 141 and the 2 nd member 142. The cup-shaped bulging portion 143 has: an annular side wall 143a, and a top wall 143b connected to the side wall 143 a. The side wall portion 143a is connected to the flange portion 144 in one opening edge. The top wall portion 143b is connected to the other opening edge of the side wall portion 143a, and closes the other opening of the side wall portion 143 a. The bulging portion 143 is manufactured by, for example, drawing, and in this case, the side wall portion 143a and the other side surface 44b are integrally formed.
In addition, from the viewpoint of improving energy efficiency determined by the ratio of the battery capacity of the stacked cell 101 to the volume of the stacked cell 101, the side wall portion 143a preferably rises from the flange portion 144, that is, rises from the flange portion 144 at an angle close to 90 °. In the case of manufacturing the 2 nd member 142 by drawing by pressing, in order to ensure high energy efficiency, the rising angle θ x of the side wall portion 143a with respect to the flange portion 144 is preferably greater than 90 ° and 110 ° or less, more preferably 105 ° or less, and still more preferably 100 ° or less. The rising angle θ x is a smaller angle (inferior angle) of the angles formed by the side wall portion 143a and the flange portion 144 shown in fig. 13.
The tab 103 functions as a terminal in the stacked battery 101. The positive electrode plate 110X (the 1 st electrode plate 110) of the membrane electrode assembly 105 is electrically connected to one tab 103, and the negative electrode plate 120Y (the 2 nd electrode plate 120) of the membrane electrode assembly 105 is electrically connected to the other tab 103. The tab 103 may be formed using aluminum, nickel-plated copper, or the like. The pair of lugs extend from the inside of the outer package 140 to the outside of the outer package 140. In the illustrated example, the tab 103 extends from the membrane electrode assembly 105 to the outside of the exterior package 140 in the lead-out direction dx.
Between the exterior package 140 and the terminal 103, a region extending beyond the terminal 103 is sealed. Specifically, as shown in fig. 9 and 14, the sealant 104 is provided between the tab 103 and the exterior package 140. And a sealant 104 sealing between the tab 103 and the exterior package 140 and sealing the receiving space of the exterior package 140. The sealant 104 has adhesiveness and bonds the tab 103 and the exterior package 140. As shown in fig. 14, the sealant 104 is provided on both sides of the tab 103 in the lamination direction dz of the electrode plates 110, 120, respectively.
Next, the membrane electrode assembly 105 will be described mainly with reference to specific examples shown in the drawings. The membrane electrode assembly 105 includes: a positive electrode plate 110X (1 st electrode plate 110) and a negative electrode plate 120Y (2 nd electrode plate 120), and an insulator 130 between the positive electrode plate 110X and the negative electrode plate 120Y. First, the positive electrode plate 110X and the negative electrode plate 120Y will be described.
As shown in fig. 10, 11, 13, and 14, the membrane electrode assembly 105 includes: a plurality of positive electrode plates 110X (1 st electrode plate 110) and negative electrode plates 120Y (2 nd electrode plate 120). The positive electrode plate 110X (1 st electrode plate 110) and the negative electrode plate 120Y (2 nd electrode plate 120) are contained in one outer package 140, for example, 10 or more pieces, 15 or more pieces, or 20 or more pieces. The positive electrode plates 110X and the negative electrode plates 120Y are alternately arranged in the lamination direction dz. The membrane electrode assembly 105 and the stacked cell 101 have a flat shape as a whole, have a small thickness in the stacking direction dz, and extend in the lead-out direction dx and the width direction dy perpendicular to the stacking direction dz.
In the non-limiting example shown, the positive plates 110X and the negative plates 120Y have an outer contour of rectangular shape. The positive electrode plate 110X and the negative electrode plate 120Y have a longitudinal direction in a lead-out direction dx perpendicular to the stacking direction dz, and a width direction in a width direction dy perpendicular to both the stacking direction dz and the lead-out direction dx. As shown in fig. 10 and 12, the positive electrode plate 110X and the negative electrode plate 120Y are arranged to be shifted in the lead-out direction dx. More specifically, the plurality of positive electrode plates 110X are disposed closer to one side in the lead-out direction dx (lower left side in fig. 10 and left side in fig. 12), and the plurality of negative electrode plates 120Y are disposed closer to the other side in the lead-out direction dx (upper right side in fig. 10 and right side in fig. 12). The positive electrode plate 110X and the negative electrode plate 120Y overlap each other at the center in the lead-out direction dx in the stacking direction dz. In fig. 10, the insulator 130 is not shown.
The positive electrode plate 110X (the 1 st electrode plate 110) has a sheet-like outer shape as shown in the drawing. The positive electrode plate 110X (1 st electrode plate 110) includes: a positive electrode current collector 111X (the 1 st electrode current collector 111), and a positive electrode active material layer 112X (the 1 st electrode active material layer 112) provided on the positive electrode current collector 111X. In the lithium ion secondary battery, the positive electrode plate 110X emits lithium ions during discharge and absorbs lithium ions during charge.
The positive electrode collector 111X has a1 st surface 111a and a 2 nd surface 111b facing each other as main surfaces. The positive electrode active material layer 112X is formed on at least one of the 1 st surface 111a and the 2 nd surface 111b of the positive electrode collector 111X. Specifically, when the 1 st surface 111a or the 2 nd surface 111b of the positive electrode collector 111X is positioned on the outermost side in the stacking direction dz of the electrode plates 110 and 120 included in the membrane electrode assembly 105, the positive electrode active material layer 112X is not provided on the outermost surface of the positive electrode collector 111X. The plurality of positive electrode plates 110X included in the stacked-type battery 101 may have the positive electrode active material layers 112X on both sides of the positive electrode collector 111X and be set to the same configuration as each other, except for the presence or absence of the positive electrode active material layer 112X depending on the position of the positive electrode collector 111X.
The positive electrode current collector 111X and the positive electrode active material layer 112X can be produced by various production methods using various materials suitable for the stacked battery 101 (lithium ion secondary battery). As one example, the positive electrode collector 111X may be formed of aluminum foil. The positive electrode active material layer 112X may include, for example: a positive electrode active material, a conductive auxiliary agent, and a binder as a binder. The positive electrode active material layer 112X can be prepared by: a slurry for a positive electrode obtained by dispersing a positive electrode active material, a conductive auxiliary agent, and a binder in a solvent is applied to a material to be the positive electrode current collector 111X and cured. As the positive electrode active material, for example, a lithium metalate compound represented by a general formula LiMxOy (where M is a metal, and x and y are a composition ratio of the metal M and oxygen O) is used. Specific examples of the lithium metal oxide compound include: lithium cobaltate, lithium nickelate, lithium manganate, etc. As the conductive assistant, acetylene black or the like can be used. As the binder, polyvinylidene fluoride or the like can be used.
As shown in fig. 12, the positive electrode collector 111X (the 1 st electrode collector 111) has: a1 st end region a3 and a1 st electrode region b 3. The positive electrode active material layer 112X (the 1 st electrode active material layer 112) is disposed only in the 1 st electrode region b3 of the positive electrode collector 111X. The 1 st end region a3 and the 1 st electrode region b3 are aligned in the lead-out direction dx. The 1 st end region a3 is located further to the outside in the lead-out direction dx (left side in fig. 12) than the 1 st electrode region b 3. As shown in fig. 14, the plurality of positive electrode current collectors 111X are joined and electrically connected to the 1 st end region a3 by resistance welding, ultrasonic welding, tape bonding, welding, or the like. In the illustrated example, one tab 103 is electrically connected to the positive electrode collector 111X in the 1 st end region a 3. The tab 103 extends from the membrane electrode assembly 105 in the direction dx. On the other hand, as shown in fig. 12, the 1 st electrode region b3 is located in a region facing the negative electrode active material layer 22Y of the negative electrode plate 120Y, which will be described later. As shown in fig. 13, the width of the positive electrode plate 110X in the width direction dy is smaller than the width of the negative electrode plate 120Y in the width direction dy. With the arrangement of the 1 st electrode region b3, lithium can be prevented from being deposited from the positive electrode active material layer 112X.
Next, the negative electrode plate 120Y (the 2 nd electrode plate 120) will be explained. The negative electrode plate 120Y has a sheet-like outer shape, as with the positive electrode plate 110X. The negative electrode plate 120Y (the 2 nd electrode plate 120) has: a negative electrode current collector 121Y (the 2 nd electrode current collector 121), and a negative electrode active material layer 122Y (the 2 nd electrode active material layer 122) provided on the negative electrode current collector 121Y. In the lithium ion secondary battery, the negative electrode plate 120Y absorbs lithium ions during discharge and releases lithium ions during charge.
The negative electrode current collector 121Y has a1 st surface 121a and a 2 nd surface 121b facing each other as main surfaces. The anode active material layer 122Y is formed on at least one of the 1 st surface 121a and the 2 nd surface 121b of the anode current collector 121Y. Specifically, when the 1 st surface 121a or the 2 nd surface 121b of the negative electrode current collector 121Y is positioned on the outermost side in the stacking direction dz of the electrode plates 110 and 120 included in the membrane electrode assembly 105, the negative electrode active material layer 122Y is not provided on the outermost surface of the negative electrode current collector 121Y. The plurality of negative electrode plates 120Y included in the stacked-type battery 101 may have the negative electrode active material layers 122Y on both sides of the negative electrode collector 121Y and be set to the same configuration as each other, except for the presence or absence of the negative electrode active material layer 122Y depending on the position of the negative electrode collector 121Y.
The negative electrode current collector 121Y and the negative electrode active material layer 122Y can be produced by various production methods using various materials suitable for the stacked battery 101 (lithium ion secondary battery). As an example, the negative electrode collector 121Y may be formed of, for example, a copper foil. The anode active material layer 122Y may include, for example: a negative electrode active material containing a carbon material and a binder functioning as a binder. The anode active material layer 122Y can be prepared, for example, by: a slurry for a negative electrode, which is obtained by dispersing a negative electrode active material including carbon powder, graphite powder, or the like, and a binder such as polyvinylidene fluoride in a solvent, is applied to a material to be the negative electrode current collector 121Y and cured.
As shown in fig. 12, the negative electrode collector 121Y (the 2 nd electrode collector 121) has a 2 nd end region a4 and a 2 nd electrode region b 4. The negative electrode active material layer 122Y (the 2 nd electrode active material layer 122) is disposed in the 2 nd electrode region b4 of the negative electrode current collector 121Y. The 2 nd end region a4 and the 2 nd electrode region b4 are aligned in the lead-out direction dx. The 2 nd end region a4 is located further to the outside in the lead-out direction dx (right side in fig. 12) than the 2 nd electrode region b 4. The plurality of negative electrode collectors 121Y are joined to each other by resistance welding, ultrasonic welding, tape bonding, welding, or the like in the 2 nd end region a4, and electrically connected to each other. One tab 103 may be electrically connected to the negative electrode collector 121Y in the 2 nd end region a 4. The tab 103 extends from the membrane electrode assembly 105 in the direction dx.
As described above, the 1 st electrode region b3 of the positive electrode plate 110X is located inside the region facing the 2 nd electrode region b4 of the negative electrode plate 120Y (see fig. 12). That is, the 2 nd electrode region b4 extends in a region including a region facing the positive electrode active material layer 112X of the positive electrode plate 110X. As shown in fig. 13, the negative electrode plate 120Y has a width in the width direction dy greater than that of the positive electrode plate 110X. In particular, one end 120a of the negative electrode plate 120Y in the width direction dy is closer to one side s1 in the width direction dy than the one end 110a of the positive electrode plate 110X in the width direction dy, and the other end 20b of the negative electrode plate 120Y in the width direction dy is closer to the other side s2 in the width direction dy than the other end 10b of the positive electrode plate 110X in the width direction dy.
Next, the insulator 130 will be explained. The insulator 130 is located between the positive electrode plate 110X (1 st electrode plate 110) and the negative electrode plate 120Y (2 nd electrode plate 120). The insulator 130 prevents a short circuit caused by contact of the positive electrode plate 110X (1 st electrode plate 110) and the negative electrode plate 120Y (2 nd electrode plate 120). The insulator 130 preferably has: a large ion permeability (air permeability), a given mechanical strength, and durability to an electrolytic solution, a positive electrode active material, a negative electrode active material, and the like. As such an insulator 130, for example,: a porous body made of an insulating material, a nonwoven fabric, or the like. The electrolyte solution is sealed in the outer package 140 together with the membrane electrode assembly 105. The electrolyte solution is impregnated with the insulator 130 made of a porous material or a nonwoven fabric, and the electrode active material layers 12 and 22 of the electrode plates 110 and 120 are in contact with the electrolyte solution.
In embodiment 2, a single insulator 130 is located between any two electrode plates 110 and 120 adjacent to each other in the stacking direction dz. The insulator 130 is a bendable sheet member. The insulator 130 has a1 st surface 130a and a 2 nd surface 130b as a pair of main surfaces opposed to each other. As shown in fig. 11 and 13, the insulators 130 are alternately folded back in the width direction dy in the opposite direction, and extend in sequence between the positive electrode plates 110X and the negative electrode plates 120Y adjacent to each other in the stacking direction dz. The insulator 130 has: the 1 st folded portion 131 folded back at one side s1 in the width direction dy, and the 2 nd folded portion 132 folded back at the other side s2 opposite to the one side s1 in the width direction dy. That is, the insulator 130 is in a U-folded shape.
The 1 st folded portion 131 is located on one side s1 in the width direction dy of one end portion 110a in the width direction dy of the positive electrode plate 110X. In the illustrated example, the 1 st folded portion 131 is folded back at a position separated from one end portion 110a in the width direction dy of the positive electrode plate 110X in the width direction dy. That is, a gap is formed between one end 110a of the positive electrode plate 110X and the 1 st folded portion 131. The positive electrode plate 110X is covered with the insulator 130 from the side of the one end portion 110 a. Each positive electrode plate 110X is located: between portions of the pair of insulators 130 on both sides of one 1 st turn-back portion 131. Each positive electrode plate 110X faces the 1 st surface 130a of the insulator 130. On the other hand, the other end 110b of the positive electrode plate 110X in the width direction dy is not covered with the insulator 130 from the other side in the width direction dy. As shown in fig. 13, the other end 110b of the positive electrode plate 110X faces the outer package 140 in the width direction dy.
The 2 nd folded portion 132 is located on the other side s2 in the width direction dy of the other end portion 120b in the width direction dy of the negative electrode plate 120Y. In the illustrated example, the 2 nd folded-back portion 132 is folded back at a position separated from the other-side end portion 120b of the negative electrode plate 120Y in the width direction dy. That is, a gap is formed between the other end 120b of the negative electrode plate 120Y and the 2 nd folded portion 132. The negative electrode plate 120Y is covered with the insulator 130 from the other end 120 b. Each negative electrode plate 120Y is located: between portions of the pair of insulators 130 on both sides of one 2 nd turn-back portion 132. Each negative electrode plate 120Y faces the 2 nd surface 130b of the insulator 130. The other end 120b of the negative electrode plate 120Y in the width direction dy is not covered with the insulator 130 from the other side in the width direction dy. As shown in fig. 13, the other end 120b of the negative electrode plate 120Y faces the external packaging body 140 in the width direction dy.
As shown in fig. 12, in a plan view, the insulator 130 extends so as to cover the entire positive electrode active material layer 112X of the positive electrode plate 110X. Therefore, as shown in fig. 13, the width of the insulator 130 in the width direction dy is larger than the width of the positive electrode plate 110X in the width direction dy. That is, the length in the width direction dy between the one end 131a and the other end 132b of the insulator 130 in the width direction dy is larger than the width of the positive electrode plate 110X in the width direction dy. The length of the insulator 130 in the lead-out direction dx is longer than the length of the positive electrode active material layer 112X in the lead-out direction dx.
Similarly, as shown in fig. 12, the insulator 130 is expanded so as to cover the entire region of the negative electrode active material layer 122Y of the negative electrode plate 120Y in a plan view. That is, the width of the insulator 130 in the width direction dy is larger than the width of the negative electrode plate 120Y in the width direction dy. That is, the length in the width direction dy between the one end 131a and the other end 132b of the insulator 130 in the width direction dy is larger than the width of the negative electrode plate 120Y in the width direction dy. The length of the insulator 130 in the lead-out direction dx is longer than the length of the negative electrode active material layer 122Y in the lead-out direction dx.
As the insulator 130, a resin porous film can be used. More specifically, as the insulator 130, a porous film containing a thermoplastic resin having a melting point of about 80 to 140 ℃ can be used. As the thermoplastic resin, there can be used: polyolefin polymers such as polypropylene and polyethylene.
Further, the insulator 130 may have: the substrate layer, the functional layer of stromatolite on the substrate layer. With this configuration, the 1 st surface 130a of the insulator 130 facing the positive electrode plate 110X and the 2 nd surface 130b of the insulator 130 facing the negative electrode plate 120Y can have different properties. For example, the functional layer having a high porosity may be disposed to face the negative electrode plate 120Y having a large area and allowing easy drying of the electrolyte, and the base layer may be disposed to face the positive electrode plate 110X. As another example, the functional layer having excellent heat resistance may be disposed to face the positive electrode plate 110X, which is likely to be heated, and the base layer may be disposed to face the negative electrode plate 120Y. As the substrate layer, for example, the resin porous film described above can be used. As the functional layer, for example, a layer containing an inorganic material can be used. The inorganic material can impart excellent heat resistance, for example, heat resistance of 150 ℃. Examples of such inorganic materials include: by using such an inorganic material, a fibrous material or a particulate material such as alumina particles can be provided with a higher porosity in the functional layer than in the base material layer.
Here, as described in the related art section, defects such as pinholes may occur in the coating layer 140b of the exterior packaging body 140. In addition, the coating layer 140b may be partially damaged due to contact between the exterior package 140 and the electrode plates 110 and 120 during use of the stacked battery 101. When the coating layer 140b is defective and the electrode plates 110 and 120 are brought into contact with the exterior package 140 and short-circuited, the stacked battery 101 may not function effectively.
On the other hand, in embodiment 2, the insulators 130 are alternately turned back in the width direction dy in the opposite direction to insulate the positive electrode plates 110X and the negative electrode plates 120Y adjacent to each other in the stacking direction dz. The insulator 130 includes: a1 st folded portion 131 folded back at one side in the width direction dy of one end portion 110a of the positive electrode plate 110X, and a 2 nd folded portion 132 folded back at the other side in the width direction dy of the other end portion 120b of the negative electrode plate 120Y. The width of the positive electrode plate 110X in the width direction dy is smaller than the width of the negative electrode plate 120Y in the width direction dy.
Here, fig. 13, 15, and 16 show longitudinal cross sections of the stacked-type battery 101 in the width direction dy. In particular, fig. 16 shows the area of the other side s2 in the width direction dy. As shown in fig. 16, in the negative electrode plate 120Y, the other end portion 120b in the width direction dy of the negative electrode plate 120Y is covered from the other side s2 in the width direction dy by the 2 nd folded portion 132 of the insulator 130. That is, the 2 nd folded portion 132 of the insulator 130 is provided between the other end 120b of the negative electrode plate 120Y and the inner surface of the exterior package 140. Therefore, the second-side end 120b of the 2 nd electrode plate 120 is effectively prevented from contacting the exterior package 140 and causing a short circuit by the 2 nd folded portion 132 of the insulator 130.
The width of the negative electrode plate 120Y in the width direction dy is larger than the width of the positive electrode plate 110X in the width direction dy. The other end 120b of the negative electrode plate 120Y is closer to the other side s2 in the width direction dy than the other end 110b of the positive electrode plate 110X. Therefore, as shown in fig. 16, the other end 120b of the 2 nd folded portion 132 in the width direction dy is closer to the other side s2 in the width direction dy than the other end 110b of the positive electrode plate 110X adjacent to the negative electrode plate 120Y corresponding to the 2 nd folded portion 132 in the stacking direction dz. Here, the "negative electrode plate 120Y corresponding to the 2 nd folded portion 132" means "the negative electrode plate 120Y" in the width direction dy where the "2 nd folded portion 132" is located, in other words, "the negative electrode plate 120Y" facing the "2 nd folded portion 132" in the width direction dy.
With this configuration, as shown in fig. 13 and 16, on the other side s2 in the width direction dy, the 2 nd folded portion 132 of the insulator 130 is closer to the outer package 140 than the other end 110b of the positive electrode plate 110X and the other end 120b of the negative electrode plate 120Y. In other words, the 2 nd turn-back portion 132 of the insulator 130 is located in the width direction dy: between the other end 110b of the positive electrode plate 110X and the inner surface of the exterior package 140, and between the other end 120b of the negative electrode plate 120Y and the inner surface of the exterior package 140. In the illustrated example, the 2 nd folded portion 132 is in contact with the inner surface of the exterior package 140 in the width direction dy, and the other end portion 110b of the positive electrode plate 110X and the other end portion 120b of the negative electrode plate 120Y are separated from the exterior package 140 in the width direction dy. Therefore, the second-side end 110b of the positive electrode plate 110X and the second-side end 120b of the negative electrode plate 120Y can be effectively prevented from contacting the inner surface of the exterior package 140 and causing a short circuit by the 2 nd folded portion 132 of the insulator 130.
In addition, in embodiment 2, the contact between the positive electrode plate 110X and the negative electrode plate 120Y and the outer package 140 is restricted on the side s1 in the width direction dy. Fig. 15 shows an area of one side s1 in the width direction dy. As shown in fig. 15, in the positive electrode plate 110X, one end portion 110a in the width direction dy of the positive electrode plate 110X is covered from one side s1 in the width direction dy by the 1 st folded portion 131 of the insulator 130. Therefore, the 1 st folded portion 131 of the insulator 130 effectively prevents the one end portion 110a of the positive electrode plate 110X from contacting the inner surface of the exterior package 140 and causing a short circuit.
Here, one end 110a of the positive electrode plate 110X is closer to the other side s2 in the width direction dy than one end 120a of the negative electrode plate 120Y. However, the 1 st folded portion 131 has a sufficient gap in the width direction dy with respect to the one end portion 110a of the positive electrode plate 110X. Further, one end 131a of the 1 st folded portion 131 in the width direction dy is closer to the one side s1 in the width direction dy than one end 120a of the negative electrode plate 120Y adjacent to the positive electrode plate 110X corresponding to the 1 st folded portion 131. Here, the "positive electrode plate 110X corresponding to the 1 st folded portion 131" means "the positive electrode plate 110X" in the width direction dy where the "1 st folded portion 131" is located, in other words, it is "the positive electrode plate 110X" where the "1 st folded portion 131" faces upward in the width direction dy.
With this configuration, as shown in fig. 13 and 15, on one side s1 in the width direction dy, the 1 st folded portion 131 of the insulator 130 is closer to the outer package 140 than the one end 110a of the positive electrode plate 110X and the one end 110a of the negative electrode plate 120Y. In other words, the 2 nd turn-back portion 132 of the insulator 130 is located in the width direction dy: between the other end 110b of the positive electrode plate 110X and the inner surface of the exterior package 140, and between the other end 120b of the negative electrode plate 120Y and the inner surface of the exterior package 140. In the illustrated example, in particular, the 1 st folded portion 131 is in contact with the outer package 140 in the width direction dy, and the one end portion 110a of the positive electrode plate 110X and the one end portion 120a of the negative electrode plate 120Y are separated from the outer package 140 in the width direction dy. Therefore, the 1 st folded portion 131 of the insulator 130 can effectively prevent the one end portion 110a of the positive electrode plate 110X and the other end portion 120b of the negative electrode plate 120Y from contacting the inner surface of the exterior package 140 and causing a short circuit.
As described above, the 1 st and 2 nd folded portions 131 and 132 of the insulator 130 can effectively prevent the positive and negative electrode plates 110X and 120Y from contacting the inner surface of the exterior body 140 in the width direction dy and causing a short circuit.
From the viewpoint of effectively preventing the short circuit between the positive electrode plate 110X and the negative electrode plate 120Y and the outer package 140, the one-side end 131a of the 1 st folded portion 131 is preferably offset to the one-side s1 in the width direction dy by 0.1mm or more, more preferably by 0.5mm or more, and still more preferably by 0.8mm or more from the one-side end 120a of the negative electrode plate 120Y adjacent to the positive electrode plate 110X corresponding to the 1 st folded portion 131. That is, the length LY1 of the one-side end 131a of the 1 st folded portion 131 protruding from the one-side end 120a of the negative electrode plate 120Y adjacent to the positive electrode plate 110X corresponding to the 1 st folded portion 131 to the one side s1 in the width direction dy is preferably 0.1mm or more, more preferably 0.5mm or more, and still more preferably 0.8mm or more.
In addition, from the viewpoint of effectively preventing short-circuiting between the positive electrode plate 110X and the negative electrode plate 120Y and the outer package 140, the separation distance DY1 (see fig. 15) between the one end 120a of the negative electrode plate 120Y and the inner surface of the outer package 140 in the width direction DY is preferably 0.1mm or more, more preferably 0.5mm or more, and still more preferably 0.8mm or more. In the illustrated example, one end 131a of the 1 st folded portion 131 is in contact with the inner surface of the exterior package 140. Therefore, as shown in fig. 15, the separation interval DY1 is the same as the protruding length LY 1.
On the other hand, when the internal volume of the exterior package 140 is increased with respect to the size of the positive electrode plate 110X and the negative electrode plate 120Y, the energy density of the stacked battery 101 decreases. From this viewpoint, the projecting length LY1 and the separation distance DY1 are preferably 3mm or less, more preferably 2mm or less, and further preferably 1mm or less.
Similarly, from the viewpoint of improving the energy density, the other end 132b of the 2 nd folded portion 132 in the width direction dy is preferably shifted from the other end 120b of the negative electrode plate 120Y corresponding to the 2 nd folded portion 132 to the other side s2 in the width direction dy by a length of 3mm or less, more preferably 2mm or less, and still more preferably 1mm or less. That is, the length LY2 (see fig. 16) of the other end portion 132b of the 2 nd folded portion 132 protruding from the other end portion 120b of the negative electrode plate 120Y corresponding to the 2 nd folded portion 132 to the other side s2 in the width direction dy is preferably 3mm or less, more preferably 2mm or less, and still more preferably 1mm or less. The separation distance DY2 (see fig. 16) between the other end 120b of the negative electrode plate 120Y and the inner surface of the outer package 140 in the width direction DY is preferably 3mm or less, more preferably 2mm or less, and still more preferably 1mm or less.
The 2 nd folded portion 132 is located at: the other end 120b of the negative electrode plate 120Y protruding from the positive electrode plate 110X toward the other side s2 in the width direction dy is located between the inner surface of the outer package 140 and the other end 120 b. Therefore, the second-side end portion 120b of the negative electrode plate 120Y and the outer package 140 are effectively restricted from short-circuiting due to the presence of the 2 nd folded portion 132. In such a case, the projection length LY2 is preferably small from the viewpoint of improving energy efficiency. Therefore, the length LX1 of the 1 st folded part 131 protruding from the one end 110a of the positive electrode plate 110X to the one side s1 in the width direction dy is longer than the length LY2 of the 2 nd folded part 132 protruding from the other end 120b of the negative electrode plate 120Y to the other side s2 in the width direction dy.
When the side wall portion 143a of the exterior package 140 is inclined largely in the stacking direction dz, the separation distance between the side wall portion 143a and the positive and negative electrode plates 110X and 120Y having a constant width in the width direction dy largely varies in the stacking direction dz. In this case, a position where the separation distance increases occurs, and the energy efficiency of the stacked battery 101 is reduced. Therefore, from the viewpoint of improving the energy efficiency of the stacked cell 101, the angle θ x (see fig. 13) of the top wall portion 143b of the bulging portion 143 with respect to the flange portion 144 is preferably 110 ° or less, more preferably 105 ° or less, and still more preferably 100 ° or less.
However, in the case of preparing the 2 nd part 142 of the exterior package 140 by press-drawing, the angle θ x of the top wall portion 143b of the bulging portion 143 with respect to the flange portion 144 becomes larger than 90 ° in view of die cutting. Therefore, the length LX1 of the 1 st folded part 131 protruding from the one end 110a of the positive electrode plate 110X to the one side s1 in the width direction dy can be varied in the stacking direction dz. Specifically, the length LX1 over which one 1 st turn-back portion 131 protrudes is longer than: the length LX1 by which any of the other 1 st folded portions 131 farther from the flange portion 144 (closer to the top wall portion 143b) in the stacking direction dz than the one 1 st folded portion 131 protrudes. More preferably, the length LX1 over which one arbitrarily selected 1 st folded portion 131 protrudes is equal to or greater than the length LX1 over which the other 1 st folded portion 131 that is farther from the flange portion 144 (closer to the top wall portion 143b) in the stacking direction dz than the one 1 st folded portion 131 protrudes.
Similarly, the length LY2 of the 2 nd folded part 132 protruding from the other end 120b of the negative electrode plate 120Y to the other side s2 in the width direction dy may vary in the stacking direction dz. Specifically, one 2 nd turn-around portion 132 protrudes by a length LY2 longer than: a length LY2 by which any of the other 2 nd turn-back portions 132 that are farther from the flange portion 144 (closer to the top wall portion 143b) in the stacking direction dz than the one 2 nd turn-back portion 132 protrudes. More preferably, the length LY2 by which one arbitrarily selected 2 nd turn-back portion 132 protrudes is equal to or greater than the length LY2 by which the other 2 nd turn-back portion 132 that is farther from the flange portion 144 (closer to the top wall portion 143b) in the stacking direction dz than the one 2 nd turn-back portion 132 protrudes.
In the illustrated example, the length LX1 of the 1 st folded portion 131 protruding from the one end 110a of the positive electrode plate 110X to the one side s1 in the width direction DY varies depending on the separation distance DY1 in the width direction DY between the one end 120a of the negative electrode plate 120Y and the inner surface of the outer package 140 adjacent to the positive electrode plate 110X corresponding to the 1 st folded portion 131 in the stacking direction dz. As a result, all of the 1 st folded portions 131 come into contact with the outer package 140, and one end portion 120a of all of the negative electrode plates 120Y is separated from the outer package 140, thereby effectively preventing a short circuit between the positive electrode plates 110X and the negative electrode plates 120Y and the outer package 140.
Similarly, in the illustrated example, the length LY2 of the 2 nd folded portion 132 protruding from the other end 120b of the negative electrode plate 120Y to the other side s2 in the width direction DY varies according to the separation distance DY2 in the width direction DY between the negative electrode plate 120Y corresponding to the 2 nd folded portion 132 and the inner surface of the outer package 140. As a result, all of the 2 nd folded portions 132 come into contact with the outer package 140, and short circuits between the positive electrode plates 110X and 120Y and the outer package 140 are effectively prevented.
From the viewpoint of suppressing the displacement of the positive electrode plate 110X and the negative electrode plate 120Y in the width direction dy during use of the stacked battery 101, the stacked battery 101 is preferably disposed in an attitude in which the stacking direction dz is not parallel to the horizontal direction, preferably in an attitude in which the stacking direction dz forms an angle larger than 45 ° with respect to the horizontal direction, and more preferably in an attitude in which the stacking direction dz is perpendicular to the horizontal direction. In addition, from the viewpoint of suppressing the displacement of the positive electrode plates 110X and the negative electrode plates 120Y in the width direction dy during use of the stacked battery 101, the internal pressure of the exterior body 140 is preferably kept at a negative pressure, for example, 100kPa or less. In this case, the exterior package 140 is in contact with the insulator 130, and the positional displacement of the positive electrode plate 110X and the negative electrode plate 120Y can be effectively suppressed.
In embodiment 2, the stacked cell 101 includes: the electrode plates 110 (positive electrode plates 110X) and 120 (negative electrode plates 120Y) of the 1 st electrode and the 2 nd electrode are alternately stacked in the stacking direction dz, and the insulators (separators) 130 are alternately and reversely folded in the width direction dy and extend between the 1 st electrode plates 110 and the 2 nd electrode plates 120 adjacent to each other in the stacking direction dz. The insulator 130 includes: the 1 st folded portion 131 folded back at one side s1 in the width direction dy of one end 120a of the 2 nd electrode plate 120, and the 2 nd folded portion 132 folded back at the other side s2 in the width direction dy of the other end 120b of the 2 nd electrode plate 120. The width of the 1 st electrode plate 110 in the width direction dy is smaller than the width of the 2 nd electrode plate 120 in the width direction dy. One end 131a of the 1 st folded portion 131 is closer to the one side s1 in the width direction dy than the other end 120b of the 2 nd electrode plate 120 adjacent to the 1 st electrode plate 110 corresponding to the 1 st folded portion 131.
In embodiment 2, the 1 st folded part 131 of the insulator 130 protrudes in the width direction from the wide 2 nd electrode plate 120 (negative electrode plate 120Y). Therefore, not only the contact between the 1 st electrode plate 110 (positive electrode plate 110X) and the inner surface of the exterior package 140 but also the contact between the wide 2 nd electrode plate 120 and the inner surface of the exterior package 140 can be effectively prevented. Thus, even when a defect such as a pinhole is formed in the coating layer 140b of the exterior body 140, short-circuiting between the exterior body 140 and the electrode plates 110 and 120 can be effectively prevented. As a result, the reliability of the stacked battery 101 can be improved.
In embodiment 2, the stacked cell 101 includes: the electrode assembly includes a1 st electrode plate 110 (positive electrode plate 110X) and a 2 nd electrode plate 120 (negative electrode plate 120Y) alternately laminated in a lamination direction dz, an insulator (separator) 30 alternately folded back in the width direction dy in the opposite direction and extending between the 1 st electrode plate 110 and the 2 nd electrode plate 120 adjacent in the lamination direction dz, and an exterior package 140 housing the 1 st electrode plate 110, the 2 nd electrode plate 120, and the insulator 130. The insulator 130 includes: the 1 st folded portion 131 folded back at one side s1 in the width direction dy of one end 120a of the 2 nd electrode plate 120, and the 2 nd folded portion 132 folded back at the other side s2 in the width direction dy of the other end 120b of the 2 nd electrode plate 120. The 1 st and 2 nd folded portions 131 and 132 are in contact with the inner surface of the exterior package 140, while the 1 st and 2 nd electrode plates 110 and 120 are restricted from being in contact with the inner surface of the exterior package 140.
In embodiment 2, the folded portions 131 and 132 of the insulator 130 protrude in the width direction dy from the electrode plates 110 and 120. Therefore, contact between the electrode plates 110 and 120 and the inner surface of the exterior package 140 can be effectively prevented. Thus, even when a defect such as a pinhole is formed in the coating layer 140b of the exterior body 140, short-circuiting between the exterior body 140 and the electrode plates 110 and 120 can be effectively prevented. As a result, the reliability of the stacked battery 101 can be improved.
In the above specific example, the one end 131a of the 1 st folded portion 131 is offset to the one side s1 in the width direction dy by 0.1mm or more from the one end 120a of the 2 nd electrode plate 120 adjacent to the 1 st electrode plate 110 corresponding to the 1 st folded portion 131. Therefore, the contact between the wide 2 nd electrode plate 120 and the inner surface of the exterior package 140 can be prevented sufficiently and stably.
In the above-described specific example, the one-side end 131a of the 1 st folded portion 131 is offset to the one-side s1 in the width direction dy by 0.1mm or more and 3mm or less from the one-side end 120a of the 2 nd electrode plate 120 adjacent to the 1 st electrode plate 110 corresponding to the 1 st folded portion 131. Therefore, the contact between the wide 2 nd electrode plate 120 and the inner surface of the exterior package 140 can be prevented sufficiently and stably. Further, the energy efficiency of the stacked cell 101 with high reliability can be improved while effectively avoiding an increase in the size of the stacked cell 101.
In the above-described specific example, the other end portion 132b of the 2 nd folded portion 132 is shifted by 3mm or less to the other side s2 in the width direction dy from the other end portion 120b of the 2 nd electrode plate 120 corresponding to the 2 nd folded portion 132. Therefore, while the 2 nd electrode plate 120 having a wide width is effectively prevented from being displaced in either one of the one side s1 and the other side s2 in the width direction dy and coming into contact with the exterior package 140, the energy efficiency of the highly reliable stacked battery can be improved.
In the specific example, the length LX1 of the 1 st turn-back portion 131 protruding from the one side end portion 110a of the 1 st electrode plate 110 to one side s1 in the width direction dy is longer than the length LY2 of the 2 nd turn-back portion 132 protruding from the other side end portion 120b of the 2 nd electrode plate 120 to the other side s2 in the width direction dy. With this configuration, the length LY2 by which the 2 nd turn-back portion 132 protrudes in the width direction dy does not become excessive, and the length LX1 by which the 1 st turn-back portion 131 protrudes in the width direction dy can be made a sufficient length while ensuring high energy efficiency of the stacked battery 101, thereby effectively preventing the one-side end 120a of the 2 nd electrode plate 120 having a wide width from coming into contact with the inner surface of the exterior package 140. Therefore, both high energy efficiency and high reliability can be imparted to the stacked battery 101.
In the specific example, the other end portion 132b of the 2 nd folded portion 132 is closer to the other side s2 in the width direction dy than the other end portion 110b of the 1 st electrode plate 110 adjacent to the 2 nd electrode plate 120 corresponding to the 2 nd folded portion 132. With this configuration, the other end 110b of the 1 st electrode plate 110 and the other end 120b of the 2 nd electrode plate 120 can be effectively prevented from contacting the inner surface of the exterior package 140.
In the specific example, one side end 120a of the 2 nd electrode plate 120 is closer to one side s1 in the width direction dy than the one side end 110a of the 1 st electrode plate 110, and the other side end 120b of the 2 nd electrode plate 120 is closer to the other side s2 in the width direction dy than the other side end 110b of the 1 st electrode plate 110. When the narrow 1 st electrode plate 110 and the wide 2 nd electrode plate 120 are arranged in this manner, both high energy efficiency and high reliability can be imparted to the stacked battery by the configuration of the 1 st folded portion 131.
In the specific example, the 1 st folded portion 131 is in contact with the exterior package 140 in the width direction dy, and the one-side end portion 120a of the 2 nd electrode plate 120 is separated from the exterior package 140 in the width direction dy. The 1 st folded portion 131 contacts the inner surface of the exterior package 140 in the width direction dy, thereby restricting the 2 nd electrode plate 120 of a wide width from contacting the exterior package 140. This effectively prevents the 2 nd electrode plate 120 and the exterior package 140 from being short-circuited, and thus can more effectively improve the reliability of the stacked battery 101.
In the specific example, the separation distance DY1 between the one-side end 120a of the 2 nd electrode plate 120 and the outer package 140 in the width direction DY is 0.1mm or more. Therefore, the contact between the wide 2 nd electrode plate 120 and the inner surface of the exterior package 140 can be prevented sufficiently and stably.
In the specific example, the separation distance DY1 between the one-side end portion 120a of the 2 nd electrode plate 120 and the exterior package 140 in the width direction is 3mm or less. With this configuration, the energy efficiency of the highly reliable stacked cell 101 can be improved while effectively avoiding an increase in the size of the stacked cell 101.
In the specific example, the exterior package 140 has: the 1 st part 141; and a 2 nd part 142 coupled with the 1 st part 141 and forming an accommodating space of the 1 st electrode plate 110, the 2 nd electrode plate 120, and the insulator 130 between the 1 st part 141. The 2 nd member 142 has: a bulging portion 143 forming an accommodation space; and a flange portion 144 connected to the expanded portion 143 so as to surround the expanded portion 143 in a ring shape and joined to the 1 st member 141. The bulging portion 143 has: an annular side wall portion 143a rising from the flange portion 144 at an angle θ x of greater than 90 ° and 110 ° or less with respect to the flange portion 144; and a top wall 143b connected to the side wall 143 a. With such a configuration, contact between electrode plates 110 and 120 and exterior package 140 can be effectively avoided without forming an excessive space between exterior package 140 and electrode plates 110 and 120. Therefore, both high energy efficiency and high reliability can be imparted to the stacked battery 101.
In the specific example, the pressure inside the outer package 140 is set to 100kPa or less. In a state where the exterior package 140 is deformed so as to be in contact with the insulator 130 protruding in the width direction dy from the electrode plates 110 and 120 by maintaining the pressure in the exterior package 140 at a pressure lower than the atmospheric pressure, the relative movement of the exterior package 140 with the electrode plates 110 and 120 and the insulator 130 is restricted. Therefore, the electrode plates 110 and 120 can be stably held in a state of being separated from the inner surface of the exterior package 140, and the reliability of the stacked battery 101 can be further improved.
In the specific example, the 1 st electrode plate 110 is a negative electrode plate 120Y, and the 2 nd electrode plate 120 is a negative electrode plate 120Y. With this configuration, the negative electrode plate 120Y can be disposed at a position facing the entire area of the positive electrode plate 110X, and the problem of deposition of the positive electrode active material can be effectively avoided, and the wide negative electrode plate 120Y can be effectively prevented from contacting the inner surface of the outer package 140.
In the specific example, the first electrode plate 110 and the second electrode plate 120 respectively include 10 or more than 10. Conventionally, in a large-capacity stacked battery 101 including 10 or more first electrode plates 110 and second electrode plates 120, respectively, positional displacement of the adjacent electrode plates 110 and 120 accumulates, and contact between the electrode plates 110 and 120 and the inner surface of the exterior package 140 tends to occur. Therefore, embodiment 2 is applied to: a large-capacity stacked battery 101 comprising 10 or more 1 st electrode plates 110 and 2 nd electrode plates 120.
The 2 nd embodiment is explained by a plurality of specific examples, but the 2 nd embodiment is not intended to be limited to these specific examples. The embodiment 2 can be implemented by other various specific examples, and various omissions, substitutions, and changes can be made without departing from the spirit thereof. For example, in this example, at least one of the 1 st electrode plate 110 (the positive electrode plate 110X) and the 2 nd electrode plate 120 (the negative electrode plate 120Y) may include an insulating layer laminated on the electrode active material layers 12, 22, in addition to the insulator 130.
Claims (26)
1. A stacked battery includes:
a plurality of electrode plates stacked in a stacking direction; and
insulating sheets which are alternately folded back in a width direction not parallel to the stacking direction and are arranged between two of the electrode plates adjacent in the stacking direction,
a gap is provided between the folded portion of the insulating sheet and an end portion of the electrode plate facing the folded portion in the width direction,
the length in the width direction between the folded portion and the end portion of the electrode plate facing the folded portion is 5 times or more the thickness of the electrode plate.
2. The stacked type battery according to claim 1,
the folded portion has a recess and a projection formed therein.
3. A stacked-type battery according to claim 1 or 2,
the length in the width direction between the folded portion and the end portion of the electrode plate facing the folded portion is 10 times or more the thickness of the electrode plate.
4. A stacked-type battery according to any one of claims 1 to 3,
the insulating sheet has a base material layer formed of a porous body.
5. A stacked-type battery as claimed in any one of claims 1 to 4,
the insulating sheet has a functional layer containing an inorganic material.
6. A stacked-type battery as claimed in any one of claims 1 to 5,
the plurality of electrode plates includes: a1 st electrode plate and a 2 nd electrode plate alternately laminated in the lamination direction, a length of the 2 nd electrode plate in the width direction being larger than a length of the 1 st electrode plate in the width direction,
the fold-back section includes: a1 st turn-back portion in which one side of the insulating sheet is turned back in the width direction, and a 2 nd turn-back portion in which the other side of the insulating sheet is turned back in the width direction,
the 1 st folded portion is located closer to one side in the width direction than an end portion on one side in the width direction of a 2 nd electrode plate adjacent to a1 st electrode plate facing the 1 st folded portion.
7. A stacked-type battery as claimed in any one of claims 1 to 6,
the plurality of electrode plates includes: a1 st electrode plate and a 2 nd electrode plate alternately laminated in the lamination direction, a length of the 2 nd electrode plate in the width direction being larger than a length of the 1 st electrode plate in the width direction,
the fold-back section includes: a1 st turn-back portion in which one side of the insulating sheet is turned back in the width direction, and a 2 nd turn-back portion in which the other side of the insulating sheet is turned back in the width direction,
the length in the width direction between the 1 st folded portion and the end portion on one side in the width direction of the 2 nd electrode plate adjacent to the 1 st electrode plate facing the 1 st folded portion is smaller than the length in the width direction between the 2 nd folded portion and the end portion on the other side in the width direction of the 2 nd electrode plate facing the 2 nd folded portion.
8. A stacked-type battery as claimed in any one of claims 1 to 7,
the plurality of electrode plates includes: a1 st electrode plate and a 2 nd electrode plate alternately laminated in the lamination direction, a length of the 2 nd electrode plate in the width direction being larger than a length of the 1 st electrode plate in the width direction,
the insulating sheet has: a substrate layer and a functional layer laminated on the substrate layer and having a higher porosity than the substrate layer,
one side of the insulating sheet is provided with the substrate layer with the 1 st electrode board is face-to-face, be provided with one side of functional layer with the 2 nd electrode board is face-to-face.
9. A stacked-type battery as claimed in any one of claims 1 to 7,
the plurality of electrode plates includes: a1 st electrode plate and a 2 nd electrode plate alternately laminated in the lamination direction, a length of the 2 nd electrode plate in the width direction being larger than a length of the 1 st electrode plate in the width direction,
the insulating sheet has: a substrate layer and a functional layer laminated on the substrate layer and having higher heat resistance than the substrate layer,
one side of the insulating sheet is provided with the substrate layer with the 2 nd electrode board is face-to-face, be provided with one side of functional layer with the 1 st electrode board is face-to-face.
10. The stacked-type battery according to any one of claims 1 to 9, further comprising: an outer package body accommodating the electrode plate and the insulating sheet,
the folded portion is in contact with the exterior package.
11. A stacked-type battery as claimed in any one of claims 1 to 10, which comprises 20 or more electrode plates in total.
12. A stacked battery includes:
a1 st electrode plate and a 2 nd electrode plate alternately laminated in a lamination direction; and
insulators alternately turned back in opposite directions in a width direction perpendicular to the stacking direction so as to extend between 1 st and 2 nd electrode plates adjacent in the stacking direction, wherein,
the insulator includes: a1 st folded portion folded back at one side in the width direction of one side end portion of the 1 st electrode plate located at one side in the width direction, and a 2 nd folded portion folded back at the other side in the width direction of the other side end portion of the 2 nd electrode plate located at the other side in the width direction,
the width of the 1 st electrode plate along the width direction is smaller than the width of the 2 nd electrode plate along the width direction,
the one-side end portion in the width direction of the 1 st folded portion is closer to one side in the width direction than a one-side end portion of the 2 nd electrode plate adjacent to the 1 st electrode plate corresponding to the 1 st folded portion.
13. The stacked type battery according to claim 12,
the one end of the 1 st folded portion is offset to one side in the width direction by 0.1mm or more from one end of the 2 nd electrode plate adjacent to the 1 st electrode plate corresponding to the 1 st folded portion.
14. The stacked type battery according to claim 12,
the one end of the 1 st folded portion is offset to one side in the width direction by 0.1mm to 3mm, as compared with one end of the 2 nd electrode plate adjacent to the 1 st electrode plate corresponding to the 1 st folded portion.
15. A stacked-type battery according to any one of claims 12 to 14,
the other end portion in the width direction of the 2 nd folded portion is offset to the other side in the width direction by 3mm or less from the other end portion of the 2 nd electrode plate corresponding to the 2 nd folded portion.
16. A stacked-type battery according to any one of claims 12 to 15,
the 1 st folded portion protrudes from the one end portion of the 1 st electrode plate to one side in the width direction by a length greater than a length of the 2 nd folded portion protruding from the other end portion of the 2 nd electrode plate to the other side in the width direction.
17. A stacked-type battery according to any one of claims 12 to 16,
the other end portion in the width direction of the 2 nd folded portion is closer to the other side in the width direction than the other end portion of the 1 st electrode plate adjacent to the 2 nd electrode plate corresponding to the 2 nd folded portion.
18. A stacked-type battery according to any one of claims 12 to 17,
one side end portion of the 2 nd electrode plate is closer to one side in the width direction than one side end portion of the 1 st electrode plate,
the other end of the 2 nd electrode plate is closer to the other side in the width direction than the other end of the 1 st electrode plate.
19. The stacked-type battery according to any one of claims 12 to 18, further comprising: an exterior packaging body accommodating the 1 st electrode plate, the 2 nd electrode plate and the insulator,
the 1 st folded-back portion is in contact with the exterior package in the width direction,
one end of the 2 nd electrode plate is separated from the exterior package in the width direction.
20. The stacked-type battery according to any one of claims 12 to 19, further comprising: an exterior packaging body accommodating the 1 st electrode plate, the 2 nd electrode plate and the insulator,
the separation distance between one side end of the 2 nd electrode plate and the external packaging body along the width direction is more than 0.1 mm.
21. The stacked-type battery according to any one of claims 12 to 20, further comprising: an exterior packaging body accommodating the 1 st electrode plate, the 2 nd electrode plate and the insulator,
the separation distance between one end of the 2 nd electrode plate and the external packaging body along the width direction is less than or equal to 3 mm.
22. A stacked battery includes:
a1 st electrode plate and a 2 nd electrode plate alternately laminated in a lamination direction;
insulators alternately turned back in opposite directions in a width direction perpendicular to the stacking direction so as to extend between 1 st and 2 nd electrode plates adjacent in the stacking direction; and
an exterior packaging body accommodating the 1 st electrode plate, the 2 nd electrode plate and the insulator,
the insulator includes: a1 st folded portion folded back at one side in the width direction of one side end portion of the 1 st electrode plate located at one side in the width direction, and a 2 nd folded portion folded back at the other side in the width direction of the other side end portion of the 2 nd electrode plate located at the other side in the width direction,
the 1 st folded portion and the 2 nd folded portion are in contact with the exterior packaging body, thereby restricting the 1 st electrode plate and the 2 nd electrode plate from being in contact with the exterior packaging body.
23. A stacked-type battery according to any one of claims 19 to 22,
the external packaging body comprises: a1 st part and a 2 nd part, the 2 nd part being engaged with the 1 st part and forming a receiving space of the 1 st electrode plate, the 2 nd electrode plate and the insulator between the 1 st part and the 2 nd part,
the 2 nd member has: a bulging portion that forms the accommodation space, and a flange portion that is connected to the bulging portion so as to annularly surround the bulging portion and that is engaged with the 1 st member,
the bulging portion has: a top wall portion that is at an angle greater than 90 ° and 110 ° or less with respect to the flange portion and rises from the flange portion, and an annular side wall portion that is connected to the side wall portion.
24. A stacked-type battery as claimed in any one of claims 19 to 23,
the pressure inside the outer package is 100kPa or less.
25. A stacked-type battery as claimed in any one of claims 12 to 24, comprising 10 or more of the 1 st electrode plate and the 2 nd electrode plate, respectively.
26. The stacked-type battery as claimed in any one of claims 6 to 9 or 12 to 25,
the 1 st electrode plate is a positive plate, and the 2 nd electrode plate is a negative plate.
Applications Claiming Priority (5)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2018-095666 | 2018-05-17 | ||
| JP2018095666A JP6835766B2 (en) | 2018-05-17 | 2018-05-17 | Stacked battery |
| JP2018135267A JP2020013705A (en) | 2018-07-18 | 2018-07-18 | Stacked battery |
| JP2018-135267 | 2018-07-18 | ||
| PCT/JP2019/019509 WO2019221232A1 (en) | 2018-05-17 | 2019-05-16 | Laminated battery |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN112119523A true CN112119523A (en) | 2020-12-22 |
Family
ID=68540382
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201980032978.7A Pending CN112119523A (en) | 2018-05-17 | 2019-05-16 | Laminated battery |
Country Status (3)
| Country | Link |
|---|---|
| CN (1) | CN112119523A (en) |
| TW (1) | TW202013796A (en) |
| WO (1) | WO2019221232A1 (en) |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2010199281A (en) * | 2009-02-25 | 2010-09-09 | Fuji Heavy Ind Ltd | Electric storage device and method of manufacturing the same |
| CN102623740A (en) * | 2011-01-31 | 2012-08-01 | 三洋电机株式会社 | Stack type battery and method of manufacturing the same |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2016143550A (en) * | 2015-02-02 | 2016-08-08 | 株式会社デンソー | Zigzag-folded laminate structure of secondary battery and battery module |
| CN114552083A (en) * | 2015-10-27 | 2022-05-27 | 株式会社半导体能源研究所 | Battery and method for manufacturing battery |
| CN111033868A (en) * | 2017-09-29 | 2020-04-17 | 远景Aesc能源元器件有限公司 | Secondary battery |
-
2019
- 2019-05-16 WO PCT/JP2019/019509 patent/WO2019221232A1/en active Application Filing
- 2019-05-16 CN CN201980032978.7A patent/CN112119523A/en active Pending
- 2019-05-17 TW TW108117127A patent/TW202013796A/en unknown
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2010199281A (en) * | 2009-02-25 | 2010-09-09 | Fuji Heavy Ind Ltd | Electric storage device and method of manufacturing the same |
| CN102623740A (en) * | 2011-01-31 | 2012-08-01 | 三洋电机株式会社 | Stack type battery and method of manufacturing the same |
Also Published As
| Publication number | Publication date |
|---|---|
| TW202013796A (en) | 2020-04-01 |
| WO2019221232A1 (en) | 2019-11-21 |
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