WO2023002807A1 - 二次電池 - Google Patents

二次電池 Download PDF

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Publication number
WO2023002807A1
WO2023002807A1 PCT/JP2022/025502 JP2022025502W WO2023002807A1 WO 2023002807 A1 WO2023002807 A1 WO 2023002807A1 JP 2022025502 W JP2022025502 W JP 2022025502W WO 2023002807 A1 WO2023002807 A1 WO 2023002807A1
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WO
WIPO (PCT)
Prior art keywords
positive electrode
secondary battery
external terminal
electrode lead
negative electrode
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
PCT/JP2022/025502
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English (en)
French (fr)
Japanese (ja)
Inventor
利宏 柴垣
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Murata Manufacturing Co Ltd
Original Assignee
Murata Manufacturing Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Murata Manufacturing Co Ltd filed Critical Murata Manufacturing Co Ltd
Priority to JP2023536661A priority Critical patent/JPWO2023002807A1/ja
Priority to CN202280050563.4A priority patent/CN117678114A/zh
Publication of WO2023002807A1 publication Critical patent/WO2023002807A1/ja
Priority to US18/411,941 priority patent/US20240154220A1/en
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

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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
    • H01M50/10—Primary casings; Jackets or wrappings
    • H01M50/183—Sealing members
    • H01M50/184—Sealing members characterised by their shape or structure
    • 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
    • H01M50/10—Primary casings; Jackets or wrappings
    • H01M50/102—Primary casings; Jackets or wrappings characterised by their shape or physical structure
    • H01M50/107—Primary casings; Jackets or wrappings characterised by their shape or physical structure having curved cross-section, e.g. round or elliptic
    • 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
    • H01M50/10—Primary casings; Jackets or wrappings
    • H01M50/102—Primary casings; Jackets or wrappings characterised by their shape or physical structure
    • H01M50/109—Primary casings; Jackets or wrappings characterised by their shape or physical structure of button or coin shape
    • 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
    • H01M50/10—Primary casings; Jackets or wrappings
    • H01M50/147—Lids or covers
    • H01M50/148—Lids or covers characterised by their shape
    • H01M50/152—Lids or covers characterised by their shape for cells having curved cross-section, e.g. round or elliptic
    • 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
    • H01M50/10—Primary casings; Jackets or wrappings
    • H01M50/172—Arrangements of electric connectors penetrating the casing
    • H01M50/174—Arrangements of electric connectors penetrating the casing adapted for the shape of the cells
    • H01M50/176—Arrangements of electric connectors penetrating the casing adapted for the shape of the cells for prismatic or rectangular cells
    • 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
    • H01M50/10—Primary casings; Jackets or wrappings
    • H01M50/172—Arrangements of electric connectors penetrating the casing
    • H01M50/174—Arrangements of electric connectors penetrating the casing adapted for the shape of the cells
    • H01M50/178—Arrangements of electric connectors penetrating the casing adapted for the shape of the cells for pouch or flexible bag cells
    • 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
    • H01M50/10—Primary casings; Jackets or wrappings
    • H01M50/183—Sealing members
    • H01M50/186—Sealing members characterised by the disposition of the sealing members
    • H01M50/188—Sealing members characterised by the disposition of the sealing members the sealing members being arranged between the lid and terminal
    • 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
    • H01M50/50—Current conducting connections for cells or batteries
    • H01M50/543—Terminals
    • H01M50/547—Terminals characterised by the disposition of the terminals on the cells
    • H01M50/548—Terminals characterised by the disposition of the terminals on the cells on opposite sides of the cell
    • 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
    • H01M50/50—Current conducting connections for cells or batteries
    • H01M50/543—Terminals
    • H01M50/547—Terminals characterised by the disposition of the terminals on the cells
    • H01M50/55—Terminals characterised by the disposition of the terminals on the cells on the same side of the cell
    • 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
    • H01M50/50—Current conducting connections for cells or batteries
    • H01M50/543—Terminals
    • H01M50/552—Terminals characterised by their shape
    • H01M50/553—Terminals adapted for prismatic, pouch or rectangular cells
    • 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
    • H01M50/50—Current conducting connections for cells or batteries
    • H01M50/543—Terminals
    • H01M50/552—Terminals characterised by their shape
    • H01M50/559—Terminals adapted for cells having curved cross-section, e.g. round, elliptic or button cells
    • 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
    • H01M50/50—Current conducting connections for cells or batteries
    • H01M50/543—Terminals
    • H01M50/562—Terminals characterised by the material
    • 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

Definitions

  • This technology relates to secondary batteries.
  • the secondary battery includes a positive electrode, a negative electrode, and an electrolyte housed inside an exterior member, and various studies have been made on the configuration of the secondary battery (see Patent Documents 1 to 3, for example).
  • Patent Literature 1 discloses a sealed power storage device in which an electrode assembly is housed in an exterior case.
  • the exterior case has, for example, a case body and a cover plate member.
  • the cover plate member is welded to an opening formed on the opposite side of the bottom of the case body.
  • Patent Document 2 discloses a secondary battery in which a battery lid is placed on a battery can containing a wound electrode body and crimped.
  • Patent Document 3 discloses a cylindrical battery having two positive electrode leads.
  • a secondary battery includes an exterior member, a battery element, external terminals, and a sealing portion.
  • the facing member includes a surface.
  • the battery element is housed in the exterior member.
  • the external terminal is attached to the exterior member so as to be electrically insulated from the exterior member, and includes a facing surface facing the surface of the exterior member in the first direction and an outer peripheral surface intersecting the facing surface.
  • the sealing portion exists in a gap between the exterior member and the external terminal and includes a first portion and a second portion.
  • the first portion is located between the exterior member and the facing surface of the external terminal and has a first thickness in the first direction.
  • the second portion is provided in contact with the outer peripheral surface and has a second thickness greater than the first thickness in the first direction.
  • a secondary battery according to an embodiment of the present technology is a second battery provided so as to be in contact with an end surface of an external terminal more than a first thickness of a first portion located between an exterior member and a facing surface of the external terminal.
  • a second thickness of the portion is large. Therefore, according to the secondary battery of the embodiment of the present technology, it is possible to exhibit stable performance.
  • FIG. 2 is a cross-sectional view showing the configuration of the secondary battery shown in FIG. 1;
  • FIG. 3 is a cross-sectional view showing the configuration of the battery element shown in FIG. 2; 3 is a partially enlarged cross-sectional view showing an enlarged view of the vicinity of the gasket shown in FIG. 2;
  • FIG. FIG. 2 is a perspective view showing the configuration of an outer can used in the manufacturing process of a secondary battery;
  • FIG. 4 is a cross-sectional view showing the configuration of an outer can for explaining the manufacturing process of the secondary battery;
  • FIG. 2 is a first explanatory view for explaining a process of heat-sealing an external terminal to a lid portion in the manufacturing process of the secondary battery shown in FIG. 1;
  • FIG. 3 is a second explanatory view for explaining a process of heat-sealing the external terminal to the lid portion in the manufacturing process of the secondary battery shown in FIG. 1;
  • 3 is a cross-sectional view showing the configuration of a secondary battery of Modification 1.
  • FIG. 9 is a partially enlarged cross-sectional view showing an enlarged view of the vicinity of the gasket shown in FIG. 8.
  • FIG. 9 is an enlarged plan view showing the external terminal shown in FIG. 8;
  • FIG. 9 is a first explanatory view for explaining a process of heat-sealing the external terminal to the lid in the manufacturing process of the secondary battery shown in FIG. 8;
  • FIG. 9 is a second explanatory view for explaining a process of thermally welding the external terminal to the lid in the manufacturing process of the secondary battery shown in FIG. 8;
  • FIG. 11 is an enlarged cross-sectional view showing a first configuration example of a main part of a secondary battery of Modification 2;
  • FIG. 11 is an enlarged cross-sectional view showing a second configuration example of a main part of a secondary battery of Modification 2;
  • FIG. 11 is a cross-sectional view showing an enlarged first configuration example of a main part of a secondary battery of Modification 3;
  • FIG. 11 is a cross-sectional view showing an enlarged second configuration example of a main part of a secondary battery of Modification 3;
  • FIG. 12 is a cross-sectional view showing the configuration of a secondary battery of modification 6;
  • FIG. 11 is a cross-sectional view showing the configuration of a secondary battery of modification 7;
  • 3 is an enlarged cross-sectional view showing the configuration of a main part of a secondary battery of Comparative Example 1.
  • FIG. 3 is a cross-sectional view showing an enlarged configuration of a main part of a secondary battery of Comparative Example 2;
  • the secondary battery described here has a flat and columnar three-dimensional shape, and is called a so-called coin type or button type. As will be described later, this secondary battery has a pair of bottom portions facing each other and a side wall portion located between the pair of bottom portions. It's getting smaller.
  • the "outer diameter” is the diameter (maximum diameter) of each of the pair of bottoms, and the “height” is the distance (maximum distance) from the surface of one bottom to the surface of the other bottom. .
  • This secondary battery includes an electrolyte together with a positive electrode and a negative electrode.
  • the charge capacity of the negative electrode is larger than the discharge capacity of the positive electrode in order to prevent electrode reactants from depositing on the surface of the negative electrode during charging. That is, the electrochemical capacity per unit area of the negative electrode is set to be larger than the electrochemical capacity per unit area of the positive electrode.
  • the type of electrode reactant is not particularly limited, but specifically light metals such as alkali metals and alkaline earth metals.
  • Alkali metals include lithium, sodium and potassium
  • alkaline earth metals include beryllium, magnesium and calcium.
  • lithium ion secondary battery A secondary battery whose battery capacity is obtained by utilizing the absorption and release of lithium is a so-called lithium ion secondary battery.
  • lithium ion secondary battery lithium is intercalated and deintercalated in an ionic state.
  • FIG. 1 shows a perspective configuration of a secondary battery.
  • FIG. 2 shows a cross-sectional configuration of the secondary battery shown in FIG.
  • FIG. 3 shows a cross-sectional configuration of the battery element 40 shown in FIG.
  • the positive electrode lead 51 is hatched, and in FIG. 3, only a part of the cross-sectional structure of the battery element 40 is enlarged.
  • the Z-axis direction shown in FIGS. 1 and 2 is the height direction of the secondary battery of the present embodiment.
  • the secondary battery described here has a three-dimensional shape in which the height H is smaller than the outer diameter D, that is, a flat and columnar three-dimensional shape.
  • the three-dimensional shape of the secondary battery is flat and cylindrical (columnar).
  • the dimensions of the secondary battery are not particularly limited, but for example, the outer diameter D is 3 mm to 30 mm and the height H is 0.5 mm to 70 mm. However, the ratio of the outer diameter D to the height H (D/H) is greater than one. Although the upper limit of this ratio (D/H) is not particularly limited, it is preferably 25 or less.
  • This secondary battery includes an outer can 10, an external terminal 20, a battery element 40, and a positive electrode lead 51, as shown in FIGS.
  • the secondary battery further includes a gasket 30 , a negative electrode lead 52 , a sealant 61 and insulating films 62 and 63 .
  • the outer can 10 is a hollow outer member that houses the battery element 40 and the like.
  • the outer can 10 has a flat and cylindrical three-dimensional shape according to the three-dimensional shape of the secondary battery, which is flat and cylindrical. Therefore, the outer can 10 has a pair of bottom portions M1 and M2 facing each other and a side wall portion M3 positioned between the bottom portions M1 and M2. An upper end portion of the side wall portion M3 is connected to the bottom portion M1, and a lower end portion of the side wall portion M3 is connected to the bottom portion M2.
  • the outer can 10 since the outer can 10 has a columnar shape, the planar shapes of the bottoms M1 and M2 are circular, and the surface of the side wall M3 is a convex curved surface.
  • the outer can 10 also includes a storage portion 11 and a lid portion 12 that are welded together, and the storage portion 11 is sealed by the lid portion 12 . That is, the lid portion 12 is welded to the storage portion 11 .
  • the storage part 11 is a flat and columnar storage member that stores the battery element 40 and the like inside. Since the housing portion 11 has a hollow structure with an open upper end and a closed lower end, it has an opening 11K at its upper end.
  • the lid portion 12 is a substantially disk-shaped lid member that closes the opening portion 11K of the storage portion 11, and has a through hole 12K. Through-hole 12K is used as a connection path for connecting battery element 40 and external terminal 20 to each other.
  • the lid portion 12 is welded to the storage portion 11 at the opening portion 11K as described above. Since the external terminals 20 are attached to the lid portion 12 , the lid portion 12 supports the external terminals 20 .
  • the lid portion 12 is already welded to the housing portion 11 as described above, so the opening portion 11K is closed by the lid portion 12 . Therefore, even if the external appearance of the secondary battery is seen, it may not be possible to confirm whether or not the storage portion 11 has the opening portion 11K.
  • the lid portion 12 is welded to the storage portion 11, welding marks remain on the surface of the outer can 10, more specifically, on the boundary between the storage portion 11 and the lid portion 12. Based on the presence or absence of , it can be confirmed after the fact whether the storage unit 11 has the opening 11K.
  • the lid portion 12 is bent so as to partially protrude toward the interior of the storage portion 11, forming a protruding portion 12P. That is, when viewed from the outside of the outer can 10, the lid portion 12 has a partially recessed shape. Therefore, when viewed from the outside of the outer can 10, the projecting portion 12P is a recessed portion 12H.
  • the through-hole 12K is provided in the protruding portion 12P or the recessed portion 12H.
  • a portion of the lid portion 12 other than the projecting portion 12P is a peripheral portion 12R.
  • the peripheral portion 12R has an annular shape surrounding the projecting portion 12P in a horizontal plane perpendicular to the height direction Z of the secondary battery.
  • the shape of the recessed portion 12H in plan view that is, the shape defined by the outer edge of the recessed portion 12H when the secondary battery is viewed from above is not particularly limited.
  • the planar view shape of the recessed portion 12H is substantially circular.
  • the inner diameter and depth of the recessed portion 12H are not particularly limited, and can be set arbitrarily.
  • the outer can 10 is a so-called welded can in which the storage portion 11 and the lid portion 12, which are physically separated from each other, are welded together.
  • the armored can 10 after welding is a single member that is physically integrated as a whole, and thus cannot be separated into the storage portion 11 and the lid portion 12 after the fact.
  • the outer can 10 which is a welded can, is a so-called crimpless can that is different from a crimped can formed using caulking. This is because the energy density per unit volume increases because the element space volume increases inside the outer can 10 .
  • This “element space volume” is the volume (effective volume) of the internal space of the outer can 10 that can be used to house the battery element 40 .
  • the armored can 10 which is a welded can, does not have a portion in which two or more members overlap each other, and does not have a portion in which two or more members overlap each other.
  • Does not have a portion folded over means that the outer can 10 is not processed (bent) so that a part of the outer can 10 is folded over. Further, “not having a portion where two or more members overlap each other” means that the outer can 10 is physically one member after the completion of the secondary battery. It literally means that it cannot be separated into two or more members. That is, the state of the outer can 10 in the secondary battery after completion is not a state in which two or more members are combined while overlapping each other so that they can be separated later.
  • each of the storage portion 11 and the lid portion 12 has conductivity.
  • the outer can 10 is electrically connected to the battery element 40 (negative electrode 42 ) through the negative electrode lead 52 , and thus functions as an external connection terminal for the negative electrode 42 . Since the secondary battery does not need to be provided with an external connection terminal for the negative electrode 42 separately from the outer can 10, the decrease in the element space volume due to the presence of the external connection terminal for the negative electrode 42 is suppressed. is. As a result, the element space volume increases, so the energy density per unit volume increases.
  • the outer can 10 contains one or more of conductive materials such as metal materials and alloy materials, and the conductive materials include iron, copper, nickel, stainless steel, These include iron alloys, copper alloys and nickel alloys.
  • the type of stainless steel is not particularly limited, but specific examples include SUS304 and SUS316.
  • the material for forming the storage portion 11 and the material for forming the lid portion 12 may be the same as or different from each other.
  • the lid portion 12 is insulated via a gasket 30 from the external terminal 20 that functions as an external connection terminal for the positive electrode 21, as will be described later. This is because a short circuit due to contact between the outer can 10, which is the external connection terminal of the negative electrode 42, and the external terminal 20, which is the external connection terminal of the positive electrode 41, is prevented.
  • the external terminal 20 is a connection terminal that is connected to an electronic device when the secondary battery is mounted on the electronic device. As described above, the external terminal 20 is attached to the outer can 10 (the lid portion 12 ), and thus is supported by the lid portion 12 . The external terminal 20 is attached to the lid portion 12 so as to block the through hole 12K.
  • the external terminal 20 is connected to the positive electrode 41 of the battery element 40 via the positive electrode lead 51 . Therefore, the external terminal 20 functions as an external connection terminal for the positive electrode 41 .
  • the secondary battery is connected to an electronic device via the external terminal 20 (the terminal for external connection of the positive electrode 41) and the outer can 10 (the terminal for external connection of the negative electrode 42). Therefore, the electronic device can operate using the secondary battery as a power source.
  • the external terminal 20 is a flat, substantially plate-shaped member and is arranged inside the recessed portion 12H with a gasket 30 interposed therebetween. Thereby, the external terminal 20 is insulated from the lid portion 12 via the gasket 30 .
  • the external terminal 20 is housed inside the recess 12 ⁇ /b>H so as not to protrude above the lid 12 . This is because the energy density per unit volume of the secondary battery is increased because the height H of the secondary battery is smaller than when the external terminal 20 protrudes upward from the lid portion 12 .
  • the outer diameter of the external terminal 20 is smaller than the inner diameter of the recess 12H. Therefore, the outer peripheral surface 20T of the external terminal 20 is separated from the lid portion 12 .
  • Gasket 30 is arranged only in part of the region between external terminal 20 and lid portion 12 (recess portion 12H). More specifically, the gaskets 30 are arranged only at locations where the external terminals 20 and the lid portion 12 would contact each other if the gaskets 30 were not present. That is, the external terminal 20 is attached to the outer can 10 via the gasket 30 so as to be electrically insulated from the outer can 10 .
  • FIG. 4 is a partially enlarged cross-sectional view showing an enlarged portion of the cross-sectional configuration of the secondary battery shown in FIG. 2 where the external terminal 20 and the lid portion 12 face each other.
  • the external terminal 20 has a facing surface 20S facing the surface 12S of the lid portion 12 of the outer can 10 in the Z-axis direction.
  • the surface 12S and the facing surface 20S are flat surfaces orthogonal to the Z-axis direction here.
  • the facing surface 20S of the external terminal 20 has a connection region 20R1 and a peripheral region 20R2.
  • the connection region 20R1 includes a connection location to which the positive lead 51 is connected.
  • the peripheral region 20R2 is a region of the facing surface 20S outside the connection region 20R1.
  • the external terminal 20 is welded to the surface 12S of the lid portion 12 via the gasket 30 in the peripheral region 20R2. That is, the gasket 30 seals the gap between the external terminal 20 and the lid portion 12 .
  • the external terminal 20 is a substantially disk-shaped member, and has an outer peripheral surface 20T curved in a substantially circular shape within a plane perpendicular to the Z-axis direction. Further, in the present embodiment, the outer peripheral surface 20T is substantially orthogonal to the facing surface 20S.
  • the connection region 20R1 is a region including the central position P of the facing surface 20S and has a substantially circular planar shape.
  • the external terminal 20 contains one or more of conductive materials such as metal materials and alloy materials, and the conductive materials are aluminum and aluminum alloys. Also, the external terminal 20 is formed of a clad material including a laminated structure of a first layer having a first rigidity and a second layer having a second rigidity higher than the first rigidity. may More specifically, the clad material forming the external terminal 20 includes a first layer mainly composed of aluminum and a second layer mainly composed of nickel in order from the side closer to the gasket 30 . The first layer 201 and the second layer 202 are roll-bonded to each other.
  • the gasket 30 is an insulating resin arranged between the outer can 10 (lid portion 12) and the external terminal 20, as shown in FIG.
  • the external terminal 20 is welded to the lid portion 12 via a gasket 30 .
  • the gasket 30 has a ring-shaped planar shape having a through hole at a location corresponding to the through hole 12K.
  • Gasket 30 includes one or more of insulating resin materials such as insulating polymer compounds, and the insulating resin materials are polypropylene, polyethylene, and the like.
  • the installation range of the gasket 30 can be arbitrarily set.
  • the gasket 30 is arranged in the gap between the surface 12S, which is the upper surface of the lid portion 12, and the opposing surface 20S, which is the lower surface of the external terminal 20, inside the recess portion 12H.
  • the gasket 30 is provided so as to seal the gap between the external terminal 20 and the lid portion 12 .
  • the gasket 30 includes a first portion 31, a second portion 32 and a third portion 33.
  • the first portion 31 is located between the surface 12S of the lid portion 12 and the facing surface 20S of the external terminal 20, and has thicknesses T1A and T1B in the Z-axis direction.
  • the thickness T1A corresponds to the distance between the edge 20EG of the external terminal 20 and the surface 12S of the lid portion 12 in the Z-axis direction.
  • the edge 20EG is a portion where the facing surface 20S and the outer peripheral surface 20T intersect. That is, the thickness T1A is the distance in the Z-axis direction between the facing surface 20S and the surface 12S at the position closest to the outer peripheral surface 20T of the facing surface 20S.
  • the thickness T1B corresponds to the distance in the Z-axis direction between the edge 12EG of the lid portion 12 and the facing surface 20S of the external terminal 20 .
  • the edge 12EG is a portion where the surface 12S and the inner peripheral surface 12T intersect. That is, the thickness T1B is the distance in the Z-axis direction between the facing surface 20S and the surface 12S at the position closest to the inner peripheral surface 12T of the facing surface 20S.
  • the thickness T1A and the thickness T1B may be different from each other or may be equal to each other.
  • the second portion 32 is provided so as to be continuous with the first portion 31 and in contact with the outer peripheral surface 20T, and has a thickness T2 that is thicker than the thickness T1A in the Z-axis direction.
  • the thickness T2 is the dimension in the Z-axis direction of the portion of the second portion 32 that is in contact with the outer peripheral surface 20T.
  • the through-hole 12K has an inner peripheral surface 12T intersecting with the surface 12S.
  • Gasket 30 further includes a third portion 33 that is provided in contact with inner peripheral surface 12T and has a thickness T3 that is thicker than thickness T1B in the Z-axis direction.
  • the thickness T3 is the dimension in the Z-axis direction of the portion of the third portion 33 that is in contact with the inner peripheral surface 12T.
  • the inner peripheral surface 12T is substantially orthogonal to the surface 12S.
  • the battery element 40 is a power generation element that advances charge/discharge reactions, and is housed inside the outer can 10 .
  • This battery element 40 includes a positive electrode 41 and a negative electrode 42 .
  • the battery element 40 further includes a separator 43 and an electrolytic solution (not shown) that is a liquid electrolyte.
  • the center line PC shown in FIG. 2 is a line segment corresponding to the center of the battery element 40 in the direction along the outer diameter D of the secondary battery (the outer can 10). That is, the position P of the center line PC corresponds to the center position of the battery element 40 .
  • the battery element 40 is a so-called wound electrode body. That is, in the battery element 40 , the positive electrode 41 and the negative electrode 42 are stacked with the separator 43 interposed therebetween. Further, the laminated positive electrode 41, negative electrode 42 and separator 43 are wound. The positive electrode 41 and the negative electrode 42 are wound while facing each other with the separator 43 interposed therebetween. Therefore, a winding center space 40K is formed at the center of the battery element 40 .
  • the positive electrode 41, the negative electrode 42, and the separator 43 are wound such that the separator 43 is arranged on the outermost circumference and the innermost circumference of the wound electrode body, respectively.
  • the number of turns of each of the positive electrode 41, the negative electrode 42 and the separator 43 is not particularly limited and can be set arbitrarily.
  • the battery element 40 Since the battery element 40 has a three-dimensional shape similar to that of the outer can 10, it has a flat and cylindrical three-dimensional shape. Compared to the case where the battery element 40 has a three-dimensional shape different from the three-dimensional shape of the outer can 10, when the battery element 40 is accommodated inside the outer can 10, a so-called dead space, specifically Therefore, a gap between the outer can 10 and the battery element 40 is less likely to occur. Therefore, the internal space of the outer can 10 is effectively utilized. As a result, the element space volume increases, and the energy density per unit volume of the secondary battery increases.
  • the positive electrode 41 is a first electrode that is used to advance charge/discharge reactions, and includes a positive electrode current collector 41A and a positive electrode active material layer 41B, as shown in FIG.
  • the positive electrode current collector 41A has a pair of surfaces on which the positive electrode active material layer 41B is provided.
  • This positive electrode current collector 41A contains a conductive material such as a metal material, and the metal material is aluminum or the like.
  • the positive electrode active material layer 41B is provided on both sides of the positive electrode current collector 41A and contains one or more of positive electrode active materials capable of intercalating and deintercalating lithium.
  • the cathode active material layer 41B may be provided only on one side of the cathode current collector 41A.
  • the positive electrode active material layer 41B may further contain a positive electrode binder, a positive electrode conductive agent, and the like.
  • a method for forming the positive electrode active material layer 41B is not particularly limited, but a specific example is a coating method.
  • the positive electrode active material contains a lithium compound.
  • This lithium compound is a general term for compounds containing lithium as a constituent element, and more specifically, a compound containing lithium and one or more transition metal elements as constituent elements. This is because a high energy density can be obtained.
  • the lithium compound may further contain one or more of other elements (excluding lithium and transition metal elements).
  • the type of lithium compound is not particularly limited, but specific examples include oxides, phosphoric acid compounds, silicic acid compounds and boric acid compounds. Specific examples of oxides are LiNiO 2 , LiCoO 2 and LiMn 2 O 4 , and specific examples of phosphoric acid compounds are LiFePO 4 and LiMnPO 4 .
  • the positive electrode binder contains one or more of synthetic rubber and polymer compounds.
  • the synthetic rubber is styrene-butadiene rubber and the like, and the polymer compound is polyvinylidene fluoride and the like.
  • the positive electrode conductive agent contains one or more of conductive materials such as carbon materials, such as graphite, carbon black, acetylene black, and ketjen black.
  • the conductive material may be a metal material, a polymer compound, or the like.
  • the negative electrode 42 is a second electrode that is used to promote charge-discharge reactions, and as shown in FIG. 3, includes a negative electrode current collector 42A and a negative electrode active material layer 42B.
  • the negative electrode current collector 42A has a pair of surfaces on which the negative electrode active material layer 42B is provided.
  • This negative electrode current collector 42A contains a conductive material such as a metal material, and the metal material is copper or the like.
  • the negative electrode active material layer 42B is provided on both sides of the negative electrode current collector 42A and contains one or more of negative electrode active materials capable of intercalating and deintercalating lithium. However, the negative electrode active material layer 42B may be provided only on one side of the negative electrode current collector 42A. Moreover, the negative electrode active material layer 42B may further contain a negative electrode binder, a negative electrode conductive agent, and the like. The details of the negative electrode binder and the negative electrode electrical conductor are the same as the details of the positive electrode binder and the positive electrode electrical conductor.
  • the method of forming the negative electrode active material layer 42B is not particularly limited, but specifically, any one of a coating method, a vapor phase method, a liquid phase method, a thermal spraying method, a firing method (sintering method), and the like, or Two or more types.
  • the negative electrode active material contains one or both of a carbon material and a metal-based material. This is because a high energy density can be obtained.
  • Carbon materials include graphitizable carbon, non-graphitizable carbon and graphite (natural graphite and artificial graphite).
  • a metallic material is a material containing as constituent elements one or more of metallic elements and semi-metallic elements capable of forming an alloy with lithium, and the metallic and semi-metallic elements are silicon and one or both of the tins, and so on.
  • the metallic material may be a single substance, an alloy, a compound, a mixture of two or more of them, or a material containing two or more phases thereof. Specific examples of metallic materials include TiSi 2 and SiO x (0 ⁇ x ⁇ 2, or 0.2 ⁇ x ⁇ 1.4).
  • the height of the negative electrode 42 is greater than the height of the positive electrode 41 . That is, the negative electrode 42 protrudes upward from the positive electrode 41 and protrudes downward from the positive electrode 41 . This is to prevent deposition of lithium released from the positive electrode 41 .
  • This "height" is a dimension corresponding to the height H of the secondary battery described above, that is, a dimension in the vertical direction, that is, the Z-axis direction in each of FIGS. 1 and 2 . The definition of height explained here is also the same hereafter.
  • the separator 43 is an insulating porous film placed between the positive electrode 41 and the negative electrode 42, as shown in FIGS.
  • the separator 43 allows lithium ions to pass through while preventing a short circuit between the positive electrode 41 and the negative electrode 42 .
  • Separator 43 contains a polymer compound such as polyethylene.
  • the height of the separator 43 is greater than the height of the negative electrode 42 . That is, the separator 43 preferably protrudes above the negative electrode 42 and protrudes below the negative electrode 42 . This is because the separator 43 is used to insulate the positive electrode lead 51 from the negative electrode 42 as will be described later.
  • the electrolyte is impregnated in each of the positive electrode 41, the negative electrode 42 and the separator 43, and contains a solvent and an electrolyte salt.
  • the solvent contains one or more of non-aqueous solvents (organic solvents) such as a carbonate-based compound, a carboxylic acid ester-based compound, and a lactone-based compound, and includes the non-aqueous solvent.
  • the electrolytic solution is a so-called non-aqueous electrolytic solution.
  • the electrolyte salt contains one or more of light metal salts such as lithium salts.
  • the positive electrode lead 51 is accommodated inside the outer can 10 as shown in FIG.
  • the positive electrode lead 51 is a connection wiring connected to the positive electrode 41 and the external terminal 20 respectively.
  • the secondary battery shown in FIG. 2 has one positive electrode lead 51 .
  • the secondary battery may have two or more positive electrode leads 51 .
  • the positive electrode lead 51 is connected to the upper end of the positive electrode 41 . Specifically, the positive electrode lead 51 is connected to the upper end portion of the positive electrode current collector 41A. Also, the positive electrode lead 51 is connected to the connection region 20R1 of the facing surface 20S of the external terminal 20 via the through hole 12K provided in the lid portion 12. As shown in FIG. A method of connecting the positive electrode lead 51 is not particularly limited, but specifically, one or more of welding methods such as resistance welding and laser welding are used. The details of the welding method described here are the same hereinafter.
  • positive lead 51 is electrically insulated from the lid portion 12 of the outer can 10 and the negative electrode 42 of the battery element 40, and is sandwiched between the lid portion 12 and the battery element 40 in the height direction of the secondary battery. It's like As shown in FIG. 4 , positive lead 51 includes first portion 511 , second portion 512 and folded portion 513 .
  • the first portion 511 and the second portion 512 extend along a horizontal plane perpendicular to the height direction Z of the secondary battery. Also, the first portion 511 and the second portion 512 overlap each other in the height direction Z of the secondary battery with the sealant 61 interposed therebetween.
  • the folded portion 513 is curved to connect the first portion 511 and the second portion 512 .
  • the first portion 511 and the second portion 512 are sandwiched between the battery element 40 and the projecting portion 12P of the lid portion 12 in the height direction Z of the secondary battery.
  • the positive electrode lead 51 is held by the lid portion 12 and the battery element 40 by extending along the lower surface of the lid portion 12 and the upper surface of the battery element 40 . Therefore, the positive electrode lead 51 is fixed inside the outer can 10 . Since the positive electrode lead 51 becomes difficult to move even when the secondary battery receives external force such as vibration and shock, the positive electrode lead 51 is less likely to be damaged.
  • the breakage of the positive electrode lead 51 as used herein means that the positive electrode lead 51 is cracked, that the positive electrode lead 51 is cut, or that the positive electrode lead 51 falls off from the positive electrode 41 .
  • a part of the positive electrode lead 51 is sandwiched between the outer can 10 and the battery element 40 means that the positive electrode lead 51 is insulated from the outer can 10 and the battery element 40 while the outer can 10 and the battery element 40 are insulated. Since the positive electrode lead 51 is held by the element 40 from above and below, even if the secondary battery is subjected to external forces such as vibration and impact, the positive electrode lead 51 is in a state where it is difficult to move inside the outer can 10. there is The fact that the positive electrode lead 51 is hard to move inside the outer can 10 means that the battery element 40 is also hard to move inside the outer can 10 . Therefore, when the secondary battery is subjected to vibration or impact, problems such as collapse of the winding of the battery element 40, which is the wound electrode body, can be avoided.
  • the positive electrode lead 51 preferably bites into the battery element 40 due to being pressed by the battery element 40 . More specifically, as described above, the height of the separator 43 is greater than the height of each of the positive electrode 41 and the negative electrode 42, so the positive electrode lead 51 digs into the upper end portion of the separator 43. is preferred. In this case, a depressed portion is formed in the upper end portion of the separator 43 due to the pressure of the positive electrode lead 51 . Since part or all of the positive electrode lead 51 is accommodated inside the recessed portion, the positive electrode lead 51 is held by the separator 43 . This is because the positive electrode lead 51 is more difficult to move inside the outer can 10, and thus the positive electrode lead 51 is less likely to be damaged.
  • the lid portion 12 includes the protruding portion 12P, and a portion of the positive electrode lead 51 is sandwiched between the protruding portion 12P and the battery element 40. That is, a portion of positive electrode lead 51 is held by protrusion 12P and battery element 40 by extending along the lower surface of protrusion 12P and the upper surface of battery element 40, respectively. Since the positive electrode lead 51 is more easily held by using the projecting portion 12P, the positive electrode lead 51 is less likely to be damaged.
  • a portion of the positive electrode lead 51 is insulated from the lid portion 12 and the negative electrode 42 via the separator 43, the sealant 61, and the insulating films 62, 63, respectively.
  • the height of the separator 43 is greater than the height of the negative electrode 42 .
  • part of the positive electrode lead 51 is separated from the negative electrode 42 via the separator 43 , and thus is insulated from the negative electrode 42 via the separator 43 . This is because a short circuit between the positive electrode lead 51 and the negative electrode 42 is prevented.
  • the positive electrode lead 51 is covered with an insulating sealant 61 .
  • a portion of the positive electrode lead 51 is insulated from each of the lid portion 12 and the negative electrode 42 via the sealant 61 . This is because a short circuit between the positive electrode lead 51 and the lid portion 12 is prevented, and a short circuit between the positive electrode lead 51 and the negative electrode 42 is also prevented.
  • An insulating film 62 is arranged between the lid portion 12 and the positive electrode lead 51 . As a result, a portion of the positive electrode lead 51 is insulated from the lid portion 12 via the insulating film 62 . This is because a short circuit between the positive electrode lead 51 and the lid portion 12 is prevented.
  • an insulating film 63 is arranged between the battery element 40 and the positive electrode lead 51 . Thereby, part of the positive electrode lead 51 is insulated from the negative electrode 42 via the insulating film 63 . This is because a short circuit between the positive electrode lead 51 and the negative electrode 42 is prevented.
  • the details of the material forming the positive electrode lead 51 are the same as the details of the material forming the positive electrode current collector 41A. However, the material for forming the positive electrode lead 51 and the material for forming the positive electrode current collector 41A may be the same as or different from each other.
  • connection position of the positive electrode lead 51 to the positive electrode 41 is not particularly limited and can be set arbitrarily. Above all, it is preferable that the positive electrode lead 51 is connected to the positive electrode 41 on the inner peripheral side of the outermost periphery of the positive electrode 41 . This is because, unlike the case where the positive electrode lead 51 is connected to the positive electrode 41 at the outermost periphery of the positive electrode 41, corrosion of the outer can 10 due to the electrolyte solution creeping up is prevented.
  • This “climbing up of the electrolyte” means that when the positive electrode lead 51 is arranged close to the inner wall surface of the outer can 10 , the electrolyte in the battery element 40 crawls up the positive electrode lead 51 and moves inside the outer can 10 . to reach the wall. When the electrolyte comes into contact with the outer can 10 due to the "electrolyte creeping up", the outer can 10 dissolves or discolors.
  • the positive electrode lead 51 is folded back once or more between the positive electrode 41 and the external terminal 20, it is folded over once or more.
  • the number of folds of the positive electrode lead 51 is not particularly limited as long as it is one or more times.
  • This "positive electrode lead 51 is folded back" means that the extending direction of the positive electrode lead 51 changes so as to form an angle larger than 90° halfway.
  • the positive electrode lead 51 is folded back at a folded portion 513 on the way from the positive electrode 41 to the external terminal 20 .
  • the first portion 511 extends from a first position P1 other than the center position P of the outer can 10 to the center position in a horizontal plane perpendicular to the height direction of the secondary battery. It extends to a second position P2 on the opposite side of the first position P1 when viewed from above.
  • the second portion 512 extends toward the central position P from the second position P2.
  • the overlapping portion of the first portion 511 and the second portion 512 is a surplus portion. That is, it can be said that the positive electrode lead 51 has a length margin in its longitudinal direction.
  • the lid portion 12 can be erected with respect to the storage portion 11 .
  • the secondary battery receives an external force such as vibration and impact, the external force is relieved by using the length margin of the positive electrode lead 51, so the positive electrode lead 51 is less likely to be damaged.
  • the connection position of the positive electrode lead 51 with respect to the positive electrode 41 can be arbitrarily changed without changing the length of the positive electrode lead 51 .
  • the length of the positive electrode lead 51 (the overall length including the length margin) is not particularly limited and can be set arbitrarily. Above all, the length of the positive electrode lead 51 is preferably half or more of the outer diameter D of the outer can 10 . This is because a length margin for erecting the lid portion 12 with respect to the storage portion 11 is ensured with respect to the length of the positive electrode lead 51 , so that the lid portion 12 can be easily erected with respect to the storage portion 11 .
  • connection range of the positive electrode lead 51 to the external terminal 20 is not particularly limited.
  • the connection range of the positive electrode lead 51 to the external terminal 20 should be sufficiently wide to prevent the positive electrode lead 51 from falling off from the external terminal 20 and sufficiently narrow to provide a length margin for the positive electrode lead 51 .
  • the reason why it is preferable that the connection range of the positive electrode lead 51 to the external terminal 20 is sufficiently narrow is that the portion of the positive electrode lead 51 that is not connected to the external terminal 20 has a length margin. is sufficiently large.
  • the positive electrode lead 51 is provided separately from the positive electrode current collector 41A. However, since the positive electrode lead 51 is physically continuous with the positive electrode current collector 41A, it may be integrated with the positive electrode current collector 41A.
  • the negative electrode lead 52 is accommodated inside the outer can 10 as shown in FIG.
  • the negative electrode lead 52 is connected to each of the negative electrode 42 and the outer can 10 (accommodating portion 11).
  • the secondary battery has one negative electrode lead 52 .
  • the secondary battery may have two or more negative electrode leads 52 .
  • the negative electrode lead 52 is connected to the lower end of the negative electrode 42, and more specifically, to the lower end of the negative electrode current collector 42A. Also, the negative electrode lead 52 is connected to the bottom surface of the housing portion 11 .
  • the details of the connection method of the negative electrode lead 52 are the same as the details of the connection method of the positive electrode lead 51 .
  • the details of the material forming the negative electrode lead 52 are the same as the details of the material forming the negative electrode current collector 42A. However, the material for forming the negative electrode lead 52 and the material for forming the negative electrode current collector 42A may be the same as or different from each other.
  • connection position of the negative electrode lead 52 to the negative electrode 42 is not particularly limited and can be set arbitrarily.
  • the negative electrode lead 52 is connected to the outermost peripheral portion of the negative electrode 42 that constitutes the wound electrode body.
  • the negative electrode lead 52 is provided separately from the negative electrode current collector 42A. However, since the negative electrode lead 52 is physically continuous with the negative electrode current collector 42A, it may be integrated with the negative electrode current collector 42A.
  • the sealant 61 is a first insulating member covering the periphery of the positive electrode lead 51 and has a tubular structure.
  • the sealant 61 covers the midway portion of the positive electrode lead 51 in order to connect the positive electrode lead 51 to each of the positive electrode 41 and the external terminal 20 .
  • the sealant 61 contains one or more of insulating materials such as insulating polymer compounds, and the insulating material is polyimide or the like.
  • the insulating film 62 is a second insulating member arranged between the lid portion 12 and the positive electrode lead 51 as shown in FIG.
  • the insulating film 62 has a ring-shaped planar shape having a through hole at a location corresponding to the through hole 12K.
  • the insulating film 62 may have an adhesive layer (not shown) on one surface, and may be adhered to either one of the lid portion 12 and the positive electrode lead 51 via the adhesive layer. Also, the insulating film 62 may have adhesive layers on both sides, and may be adhered to both the lid portion 12 and the positive electrode lead 51 via the adhesive layers.
  • the insulating film 62 may contain one or more of insulating materials such as insulating polymer compounds.
  • the insulating material included in the insulating film 62 is polyimide or the like.
  • the insulating film 63 is a third insulating member arranged between the battery element 40 and the positive electrode lead 51, as shown in FIG.
  • the insulating film 63 has a flat planar shape.
  • the insulating film 63 is arranged so as to shield the winding central space 40K and cover the battery element 40 around the winding central space 40K.
  • the details regarding the material for forming the insulating film 63 are the same as the details regarding the material for forming the insulating film 62 .
  • the material forming the insulating film 63 and the material forming the insulating film 62 may be the same as or different from each other.
  • the secondary battery may further include one or more other components.
  • the secondary battery is equipped with a safety valve mechanism.
  • This safety valve mechanism disconnects the electrical connection between the outer can 10 and the battery element 40 when the internal pressure of the outer can 10 reaches a certain level or higher.
  • causes for the internal pressure of the outer can 10 to reach a certain level or higher include occurrence of a short circuit inside the secondary battery, external heating of the secondary battery, and the like.
  • the installation location of the safety valve mechanism is not particularly limited, it is preferable that the safety valve mechanism is provided on either of the bottom portions M1 and M2, and is provided on the bottom portion M2 to which the external terminal 20 is not attached. more preferably.
  • the secondary battery may have an insulator between the outer can 10 and the battery element 40 .
  • This insulator includes one or more of an insulating film and an insulating sheet, and prevents a short circuit between the outer can 10 and the battery element 40 . Since the installation range of the insulator is not particularly limited, it can be set arbitrarily.
  • the outer can 10 is provided with an open valve.
  • This open valve opens when the internal pressure of the armored can 10 reaches a certain level or more, so that the internal pressure is released.
  • the installation location of the open valve is not particularly limited, but, like the installation location of the safety valve mechanism described above, one of the bottoms M1 and M2 is preferable, and the bottom M2 is more preferable.
  • FIG. 5 shows a perspective configuration of an outer can 10 used in the secondary battery manufacturing process, and corresponds to FIG.
  • FIG. 6 shows a cross-sectional configuration of the outer can 10 for explaining the manufacturing process of the secondary battery, and corresponds to FIG.
  • FIG. 5 shows a state in which the lid portion 12 is separated from the storage portion 11 before the lid portion 12 is welded to the storage portion 11.
  • FIG. 5 shows a state in which the lid portion 12 is erected with respect to the storage portion 11 before the lid portion 12 is welded to the storage portion 11 .
  • FIGS. 1 to 4 already described will be referred to as needed.
  • the storage portion 11 is a substantially container-like member in which a bottom portion M2 and a side wall portion M3 are integrated with each other, and has an opening portion 11K.
  • the lid portion 12 is a substantially plate-like member corresponding to the bottom portion M1, and external terminals 20 are attached in advance to recessed portions 12H provided in the lid portion 12 via gaskets 30 .
  • the storage portion 11 may be formed by preparing a bottom portion M2 and a side wall portion M3 that are physically separated from each other, and welding the side wall portion M3 to the bottom portion M2.
  • a positive electrode mixture is prepared by mixing a positive electrode active material, a positive electrode binder, a positive electrode conductive agent, and the like.
  • a pasty positive electrode mixture slurry is prepared by putting the produced positive electrode mixture into an organic solvent or the like.
  • the cathode active material layer 41B is formed by applying the cathode mixture slurry to both surfaces of the cathode current collector 41A.
  • the cathode active material layer 41B is compression-molded using a roll press or the like. In this case, the positive electrode active material layer 41B may be heated, or the compression molding may be repeated multiple times. Thereby, the positive electrode 41 is produced.
  • a negative electrode 42 is manufactured by a procedure similar to that of the positive electrode 41 . Specifically, a negative electrode mixture slurry obtained by mixing a negative electrode active material, a negative electrode binder, a negative electrode conductor, and the like is put into an organic solvent to prepare a pasty negative electrode mixture slurry, and then the negative electrode current collector 42A is prepared. The negative electrode active material layer 42B is formed by applying the negative electrode mixture slurry to both surfaces of the . After that, the negative electrode active material layer 42B is compression-molded using a roll press machine or the like. Thus, the negative electrode 42 is produced.
  • the positive electrode lead 51 whose periphery is covered with the sealant 61 is connected to the positive electrode 41 (positive electrode current collector 41A), and the negative electrode lead 52 is connected to the negative electrode 42 (negative electrode collector). 42A).
  • the stacked body including the positive electrode 41, the negative electrode 42 and the separator 43 is wound to form a wound body as shown in FIG. 40Z is produced.
  • the wound body 40Z has the same configuration as the battery element 40, except that the positive electrode 41, the negative electrode 42, and the separator 43 are not impregnated with the electrolytic solution. 5, illustration of each of the positive electrode lead 51 and the negative electrode lead 52 is omitted.
  • the wound body 40Z to which the positive electrode lead 51 and the negative electrode lead 52 are respectively connected is stored inside the storage portion 11 through the opening 11K.
  • a welding method such as resistance welding is used to connect the negative electrode lead 52 to the storage portion 11 .
  • the insulating film 63 is placed on the wound body 40Z.
  • FIG. 7A and 7B are explanatory diagrams for explaining the process of heat-sealing the external terminal 20 to the lid portion 12 in the manufacturing process of the secondary battery shown in FIG. 1, respectively.
  • the wound body 40Z (positive electrode 41) housed inside the housing portion 11 and the external terminal 20 attached to the lid portion 12 are connected to each other via the positive electrode lead 51. Therefore, as shown in FIG. 5, in a state in which the wound body 40Z and the external terminal 20 are connected to each other through the positive electrode lead 51, the lid portion 12 can be erected with respect to the storage portion 11. .
  • the phrase "standing the lid portion 12 against the housing portion 11" means that the lid portion 12 does not block the opening portion 11K, so that the battery element is placed through the positive electrode lead 51.
  • the lid portion 12 is arranged so as to be substantially orthogonal to the bottom surface of the storage portion 11 while maintaining the state in which the 40 and the external terminal 20 are connected to each other. In this case, by sufficiently increasing the length of the positive electrode lead 51, the positive electrode lead 51 is prevented from being excessively pulled or twisted even when the lid portion 12 is erected against the storage portion 11. be done.
  • the electrolytic solution is injected into the storage portion 11 through the opening portion 11K.
  • the lid portion 12 does not close the opening portion 11K.
  • the electrolytic solution can be easily injected into the inside of 11 .
  • the wound body 40Z including the positive electrode 41, the negative electrode 42, and the separator 43 is impregnated with the electrolytic solution, and the battery element 40, which is a wound electrode body, is produced.
  • the lid portion 12 is used to close the opening portion 11K, and then the lid portion 12 is attached to the storage portion 11 using a welding method such as laser welding. to weld.
  • a welding method such as laser welding. to weld.
  • a portion of the positive electrode lead 51 is sandwiched between the lid portion 12 and the battery element 40, and the positive electrode lead 51 is curved in front of the connection to the external terminal 20. folded portion 513 is formed.
  • the outer can 10 is formed, and the battery element 40 and the like are housed inside the outer can 10, thus completing the assembly of the secondary battery.
  • the secondary battery after assembly is charged and discharged.
  • Various conditions such as environmental temperature, number of charge/discharge times (number of cycles), and charge/discharge conditions can be arbitrarily set.
  • a film is formed on the surface of the negative electrode 42 and the like, so that the state of the secondary battery is electrochemically stabilized.
  • a secondary battery is completed.
  • the gasket 30 as a sealing portion that seals the gap between the lid portion 12 of the outer can 10 and the external terminal 20 has the first portion 31 and the second portion 32 . and a third portion 33.
  • the thickness T2 of the second portion 32 in contact with the outer peripheral surface 20T of the external terminal 20 is thicker than the thickness T1A of the first portion 31 provided in the gap between the surface 12S and the facing surface 20S.
  • the thickness T3 of the third portion 33 in contact with the inner peripheral surface 12T is thicker than the thickness T1B of the first portion 31 .
  • the airtightness inside the outer can 10 can be improved as compared with the case where the gasket 30 does not include the second portion 32 and the third portion 33. can. Therefore, effects such as suppression of volatilization of the electrolyte contained in the battery element 40 housed in the outer can 10 and suppression of progress of deterioration of the battery element 40 can be expected. Therefore, it is possible to realize a secondary battery that can exhibit stable performance such as charge-discharge cycle characteristics over a long period of time.
  • the recessed portion 12H is provided in the lid portion 12, and the external terminal 20 is arranged in the recessed portion 12H. Therefore, the height dimension of the secondary battery can be reduced while ensuring the battery capacity.
  • the folded portion 513 is positioned at the peripheral portion 12R of the lid portion 12, and the first portion 511 and the second portion 512 extend from the center position of the secondary battery toward the peripheral portion 12R. It extends in the radial direction of the secondary battery. Specifically, the first portion 511 extends from a first position P1 other than the center position P of the outer can 10 to a first position when viewed from the center position P within a horizontal plane perpendicular to the height direction Z of the secondary battery. It extends to a second position P2 on the opposite side of P1. The second portion 512 extends from the second position P2 toward the central position.
  • the overlapping portion of the first portion 511 and the second portion 512 is sandwiched between the protruding portion 12P and the battery element 40 . Therefore, it is possible to ensure a larger area where the first portion 511 contacts the battery element 40 via the sealant 61 and a larger area where the second portion 512 contacts the projecting portion 12P either directly or via the sealant 61 . Therefore, movement of the positive electrode lead 51 and the battery element 40 inside the outer can 10 is sufficiently restricted. Therefore, even if the secondary battery is subjected to impact or vibration, problems such as damage to the positive electrode lead 51 and collapse of the winding of the battery element 40 are less likely to occur. Therefore, the secondary battery of this embodiment can obtain excellent physical durability.
  • the secondary battery of the present embodiment which is called a coin-shaped or button-shaped secondary battery, that is, a secondary battery having a flat and columnar three-dimensional shape, has a positive electrode 41 as shown in FIGS. It has a small external terminal 20 that functions as an external connection terminal. In this case, since the size of the external terminal 20 is small, the connection area of the positive electrode lead 51 with respect to the external terminal 20 is small. Therefore, in order to maintain the electrical connection between the external terminal 20 and the positive electrode lead 51 , it is necessary to sufficiently fix the positive electrode lead 51 inside the outer can 10 .
  • the secondary battery of the present embodiment movement of the positive electrode lead 51 inside the outer can 10 is sufficiently suppressed. Therefore, even if the connection area of the positive electrode lead 51 with respect to the external terminal 20 is small, the possibility of the positive electrode lead 51 detaching from the external terminal 20 or breaking the positive electrode lead 51 is extremely low. Therefore, according to the secondary battery of the present embodiment, the electrical connection between the external terminal 20 and the positive electrode lead 51 can be maintained in good condition even when subjected to an external force such as vibration or impact. can. Therefore, according to the secondary battery of the present embodiment, high physical durability can be achieved even when miniaturized.
  • the lid portion 12 of is arranged close to the external terminal 20 . That is, the lid portion 12 and the external terminal 20, which are two external connection terminals having different polarities, are close to each other. Therefore, in order to prevent a short circuit between the lid portion 12 and the external terminal 20 , it is desirable to sufficiently reduce the connection area of the positive electrode lead 51 to the external terminal 20 and keep the positive electrode lead 51 sufficiently away from the lid portion 12 .
  • the secondary battery of the present embodiment since the movement of the positive electrode lead 51 inside the outer can 10 is sufficiently suppressed, even if the connection area of the positive electrode lead 51 with respect to the external terminal 20 is small, the external terminal The possibility of the positive electrode lead 51 detaching from 20 or breaking of the positive electrode lead 51 is extremely low. Therefore, according to the secondary battery of the present embodiment, the electrical connection between the external terminal 20 and the positive electrode lead 51 can be maintained in good condition even when subjected to an external force such as vibration or impact. can. Therefore, according to the secondary battery of the present embodiment, it is possible to achieve high physical durability while preventing a short circuit between the lid portion 12 and the external terminal 20 even when the size of the secondary battery is reduced.
  • the positive electrode lead 51 and the negative electrode 42 can be prevented from short-circuiting, a higher reliability can be obtained.
  • the sealant 61 covers the periphery of the positive electrode lead 51 and a part of the positive electrode lead 51 is insulated from the outer can 10 and the negative electrode 42 via the sealant 61, the positive electrode lead 51 and the outer case are insulated from each other. A short circuit with the can 10 is prevented, and a short circuit between the positive electrode lead 51 and the negative electrode 42 is also prevented, so that higher reliability can be obtained.
  • the positive electrode lead 51 is covered with the sealant 61, the following effects can be obtained. That is, when the positive electrode lead 51 is sandwiched between the outer can 10 and the battery element 40 with the sealant 61 interposed therebetween, a grip force is generated between the outer can 10 and the sealant 61, and a gripping force is generated between the battery element 40 and the sealant 61. grip force is generated. Thereby, the positive electrode lead 51 is easily held by the outer can 10 and the battery element 40 by utilizing the gripping force supplied to the positive electrode lead 51 through the sealant 61 . Accordingly, the positive electrode lead 51 is insulated from the outer can 10 and the negative electrode 42 via the sealant 61 . In addition, since the positive electrode lead 51 is more easily fixed inside the outer can 10 by using the sealant 61, even higher physical durability can be obtained.
  • the insulating film 62 is arranged between the outer can 10 and the positive electrode lead 51 and a part of the positive electrode lead 51 is insulated from the outer can 10 via the insulating film 62, the positive electrode lead 51 and the outer can 10 are prevented from short-circuiting. Therefore, higher reliability can be obtained.
  • the insulating film 63 is arranged between the battery element 40 and the positive electrode lead 51 and a part of the positive electrode lead 51 is insulated from the negative electrode 42 via the insulating film 63, the positive electrode lead 51 and the positive electrode lead 51 A short circuit with the negative electrode 42 is prevented. Therefore, higher reliability can be obtained.
  • the outer can 10 includes the storage portion 11 and the lid portion 12 that are welded together, and the positive electrode lead 51 is folded once or more, a length margin of the positive electrode lead 51 is obtained. Therefore, it becomes possible to stand the lid part 12 against the storage part 11 particularly in the process of forming the outer can 10 among the manufacturing processes of the secondary battery. Therefore, it becomes easier to inject the electrolytic solution, and the connection position of the positive electrode lead 51 with respect to the positive electrode 41 can be arbitrarily changed, so that higher manufacturing easiness can be obtained.
  • the lid portion 12 can be easily erected with respect to the storage portion 11 in the manufacturing process of the secondary battery. Manufacturability can be obtained.
  • the secondary battery is flat and columnar, that is, if the secondary battery is a secondary battery called a coin type or a button type, the positive electrode lead can be used even in a small secondary battery that is greatly restricted in terms of size. Since 51 is less likely to break, a higher effect can be obtained in terms of physical durability.
  • the secondary battery is a lithium-ion secondary battery, a sufficient battery capacity can be stably obtained by utilizing lithium absorption and release.
  • FIG. 2 exemplifies the secondary battery including the external terminals 20 whose facing surfaces 20S are entirely flat surfaces, but the present technology is not limited to this.
  • the secondary battery of the present disclosure includes an external terminal 20A having a groove 20U formed in the facing surface 20S as shown in FIGS. 8, 9A, and 9B. good too.
  • FIG. 8 illustrates a cross-sectional configuration of a secondary battery of Modification 1 of the present disclosure.
  • 9A is a partially enlarged cross-sectional view showing an enlarged portion of the cross-sectional structure of the secondary battery shown in FIG. 8 where the external terminal 20A and the lid portion 12 face each other.
  • FIG. 9B is a plan view showing the planar configuration of the external terminal 20A viewed from the inside of the outer can 10 in the Z-axis direction.
  • the external terminal 20A has a groove 20U provided in a facing surface 20S that faces the lid portion 12 of the outer can 10 in the Z-axis direction.
  • the configuration of the external terminal 20A is substantially the same as the configuration of the external terminal 20, except that it has a groove 20U.
  • the groove 20U is provided in the peripheral region 20R2 between the outer peripheral surface 20T of the external terminal 20A and the connection region 20R1.
  • the groove 20U is provided so as to surround the connection region 20R1. Specifically, as shown in FIG. 9B, it has an annular shape surrounding the connection region 20R1.
  • the external terminal 20A is a substantially disc-shaped member and has a substantially circular planar outer peripheral surface 20T.
  • the inner peripheral surface 12T of the through-hole 12K is located at a position overlapping the groove 20U in the Z-axis direction or at a position overlapping the peripheral region 20R2 in the Z-axis direction.
  • the gasket 30 is provided so as to partially or completely fill the grooves 20U of the external terminals 20A.
  • FIG. 10A and 10B are explanatory diagrams for explaining the process of heat-sealing the external terminal 20A to the lid portion 12 in the manufacturing process of the secondary battery shown in FIG. 8, respectively.
  • the secondary battery of Modification 1 is provided with the external terminal 20A having the groove 20U provided on the facing surface 20S. Therefore, for example, when the insulating resin 30Z that forms the gasket 30 is melted by heat and the external terminal 20A is welded to the lid portion 12 of the outer can 10, the melted insulating resin 30Z fits in the groove 20U. Therefore, it is possible to limit the area where the molten insulating resin 30Z spreads. Therefore, for example, the connection region 20R1 for connecting the positive electrode lead 51 in the facing surface 20S can be sufficiently secured with high dimensional accuracy. Therefore, in the manufacturing process of the secondary battery of the present embodiment, positive electrode lead 51 can be easily connected to connection region 20R1, and manufacturing easiness is improved.
  • the region where the molten insulating resin 30Z spreads can be limited by the groove 20U, variations in the thickness of the insulating resin 30Z can be reduced. Therefore, it is possible to suppress inclination of the external terminals 20A with respect to the lid portion 12 due to variations in spread of the insulating resin 30Z. As a result, the dimensional accuracy of the secondary battery can be improved.
  • the groove 20U is provided so as to surround the connection region 20R1, that is, so as to go around the connection region 20R1. Therefore, the plane shape of the connection region 20R1 can be ensured more accurately, and variations in the thickness of the insulating resin 30Z surrounding the connection region 20R1 can be further reduced.
  • the inner peripheral surface 12T of the through-hole 12K is positioned so as to overlap the groove 20U in the Z-axis direction or overlap the peripheral region 20R2 in the Z-axis direction. . Therefore, the widening area of the gasket 30 protruding toward the center position P from the gap between the facing surface 20S of the external terminal 20A and the surface 12S of the lid portion 12 can be effectively limited.
  • the gasket 30 is provided so as to partially or fully fill the groove 20U. Therefore, the external terminal 20A is more firmly attached to the lid portion 12 via the gasket 30. As shown in FIG.
  • the present technology is not limited to this.
  • the secondary battery of the present disclosure may include an external terminal 20B instead of the external terminal 20, like the secondary battery of Modified Example 2 shown in FIGS. 11A and 11B.
  • the secondary battery of the present disclosure may include a lid portion 12B instead of the lid portion 12, like the secondary battery of Modified Example 2 shown in FIGS. 11A and 11B.
  • the outer peripheral surface 20T includes an inclined surface 20T1 inclined with respect to the facing surface 20S and an end surface 20T2 substantially orthogonal to the facing surface 20S.
  • the inner peripheral surface 12T includes an inclined surface 12T1 inclined with respect to the surface 12S and an end surface 12T2 substantially perpendicular to the surface 12S.
  • the second portion 32 of the gasket 30 contacts from the facing surface 20S to the end surface 20T2 via the inclined surface 20T1, and the third portion 33 extends from the facing surface 20S to the inclined surface 12T1. , to the end face 12T2.
  • the gasket 30 is formed so that the second portion 32 is in contact with part of the inclined surface 20T1 and the third portion 33 is in contact with part of the inclined surface 12T1.
  • high sealing performance can be obtained as compared with a secondary battery in which the gasket 30 only contacts the facing surface 20S and does not contact the inclined surfaces 20T1 and 12T1 at all.
  • the sealing performance of the inside of the outer can 10 is higher in the secondary battery in FIG. 11A than in the secondary battery in FIG. 11B.
  • the outer peripheral surface 20T of the external terminal 20B includes the inclined surface 20T1
  • the inner peripheral surface 12T of the lid portion 12B includes the inclined surface 12T1.
  • the outer peripheral surface 20T includes the inclined surface 20T1
  • the inner peripheral surface 12T does not have to include the inclined surface 12T1.
  • the inner peripheral surface 12T includes the inclined surface 12T1
  • the outer peripheral surface 20T may not include the inclined surface 20T1.
  • the third portion 33 continuous with the first portion 31 covers at least a portion of the inner peripheral surface 12T.
  • the second portion 32 continuous with the first portion 31 may be in contact with at least a portion of the outer peripheral surface 20T
  • the third portion 33 continuous with the first portion 31 may be in contact with at least a portion of the inner peripheral surface 12T.
  • the present technology is not limited to this.
  • the secondary battery of the present disclosure may include an external terminal 20C instead of the external terminal 20, like the secondary battery of Modified Example 3 shown in FIGS. 12A and 12B.
  • the secondary battery of the present disclosure may include a lid portion 12C instead of the lid portion 12, like the secondary battery of Modified Example 3 shown in FIGS. 12A and 12B.
  • the outer peripheral surface 20T includes a curved surface 20T3 that is continuous with the facing surface 20S.
  • the inner peripheral surface 12T includes a curved surface 12T3 that is continuous with the surface 12S.
  • the thickness T2 is thicker than the thickness T1A
  • the thickness T3 is thicker than the thickness T1B.
  • the thickness T1A is the distance in the Z-axis direction between the facing surface 20S and the surface 12S at a position closest to the inclined surface 20T1 of the facing surface 20S.
  • the thickness T1B is the distance in the Z-axis direction between the facing surface 20S and the surface 12S at the position closest to the inclined surface 12T1 of the facing surface 20S.
  • the second portion 32 of the gasket 30 is in contact with the opposing surface 20S through the curved surface 20T3 to the end surface 20T2, and the third portion 33 is in contact with the opposing surface 20S through the curved surface 12T3. It is formed so as to contact up to the end face 12T2.
  • the gasket 30 is formed so that the second portion 32 is in contact with part of the curved surface 20T3 and the third portion 33 is in contact with part of the curved surface 12T3.
  • the secondary battery comprises a sealant 61 and insulating films 62,63.
  • the secondary battery of the present technology is not limited to the case where it includes all of the sealant 61 and the insulating films 62 and 63 as long as the positive electrode lead 51 is insulated from the outer can 10 and the negative electrode 42 respectively. Absent.
  • the secondary battery does not need to have the insulating film 63 .
  • the positive electrode lead 51 is insulated from each of the outer can 10 and the negative electrode 42 via the sealant 61
  • the secondary battery does not have one or both of the insulating films 62 and 63.
  • the positive electrode lead 51 is insulated from the outer can 10 and the negative electrode 42 via the separator 43 and the insulating film 62
  • the secondary battery is one or both of the sealant 61 and the insulating film 63. You don't have to have both.
  • the positive electrode lead 51 is insulated from the outer can 10 and the negative electrode 42, respectively, so that the same effects as those of the secondary battery of the above embodiment can be obtained.
  • the height of the separator 43 is higher than the height of the negative electrode 42 , so the positive electrode lead 51 is insulated from the negative electrode 42 via the separator 43 .
  • the positive electrode lead 51 is insulated from the negative electrode 42 via the separator 43. It doesn't have to be.
  • the positive electrode lead 51 is insulated from the negative electrode 42 via the insulating film 63, the same effect as the secondary battery of the above embodiment can be obtained.
  • the height of the separator 43 is preferably higher than the height of the negative electrode 42 .
  • the range of coverage of the positive electrode lead 51 with the sealant 61 is not particularly limited and can be set arbitrarily. Specifically, as shown in FIG. 13 corresponding to FIG. 2, part of the folded portion 513, the second portion 512, and the first portion 511 of the positive electrode lead 51 is coated with the sealant 61. It's okay not to. In addition, in Modification 4 shown in FIG. 8 , the portion of the first portion 511 that overlaps the second portion 512 is not covered with the sealant 61 . Electrical insulation between the positive electrode lead 51 and the battery element 40 is provided by an insulating film 63 .
  • the overlapping portion between the first portion 511 and the second portion 512 is not coated with the sealant 61, so the thickness of the overlapping portion between the first portion 511 and the second portion 512 is reduced to can be thinner.
  • the folded portion 513 is not coated with the sealant 61 either, so the thickness of the folded portion 513 can be made thinner. Therefore, the volume occupation ratio of the battery element 40 inside the outer can 10 can be further improved. Therefore, the secondary battery as Modification 6 shown in FIG. 13 is more suitable for improving the energy density per unit volume.
  • the positive electrode lead 51 is easily insulated from the outer can 10 and the negative electrode 42 via the sealant 61 in the secondary battery of FIG. 2 described in the above embodiment. , higher reliability can be obtained.
  • an armored can 10 is used in which a flat external terminal 20 is attached to the outer side of a lid portion 12 having a protruding portion 12P (or a recessed portion 12H).
  • the configuration of the outer can 10 is not particularly limited and may be changed arbitrarily. Note that the configuration of a series of secondary batteries described below has the same configuration as the configuration of the secondary battery shown in FIG. have.
  • an outer can 10 having a flat external terminal 20 attached to the outside of a flat lid portion 12 that does not have a projecting portion 12P is used. good too.
  • the external terminal 20 is attached via the gasket 30 to the outside of the lid portion 12 having the through hole 12K.
  • Example 1 a secondary battery of Modified Example 2 including the external terminal 20B and the lid portion 12B shown in FIGS. 11A and 11B was manufactured in the following manner.
  • the positive electrode mixture slurry is applied to both surfaces of the positive electrode current collector 41A (a strip-shaped aluminum foil having a thickness of 12 ⁇ m) using a coating device, and then the positive electrode mixture slurry is dried to obtain a positive electrode active material.
  • a material layer 41B is formed.
  • the welding position of the positive electrode lead 51 was adjusted so that the welding position of the positive electrode lead 51 was in the middle of the winding of the positive electrode 41 .
  • the positive electrode 41 and the negative electrode 42 are laminated with each other with a separator 43 (a microporous polyethylene film having a thickness of 25 ⁇ m and a width of 4.0 mm) interposed therebetween, and then the positive electrode 41, the negative electrode 42 and the separator 43 are wound.
  • the wound body 40Z was stored inside the storage section 11 thereof.
  • the negative electrode lead 52 was welded to the housing portion 11 using a resistance welding method.
  • the insulating resin 30Z was applied to the surface 12S of the lid portion 12B, the external terminals 20 were further placed on the insulating resin 30Z (see FIG. 7A). Polyimide was used as the insulating resin 30Z.
  • the external terminals 20B were welded to the lid portion 12B by the gasket 30 that expanded from the facing surface 20S to contact a portion of the outer peripheral surface 20T and a portion of the inner peripheral surface 12T.
  • the pressure applied to the external terminals 20B was adjusted so that the thicknesses T1A, T1B, T2 and T3 of the gaskets 30 were 0.030 mm, 0.030 mm, 0.045 mm and 0.045 mm, respectively.
  • the positive electrode lead 51 was welded to the connection region 20R1 of the external terminal 20B attached to the lid portion 12B via the gasket 30.
  • the electrolytic solution was injected into the storage portion 11 through the opening 11K.
  • the wound body 40Z (the positive electrode 41, the negative electrode 42, and the separator 43) was impregnated with the electrolytic solution, and the battery element 40 was produced.
  • the lid 12B was welded to the housing 11 using laser welding.
  • a folded portion 513 is formed in a portion of the positive electrode lead 51 so as to form a curved shape when closing the opening 11K with the lid portion 12B.
  • Example 2 a secondary battery as Example 2 was produced.
  • the amount of the insulating resin 30Z applied was adjusted so that the thicknesses T1A, T1B, T2 and T3 of the gaskets 30 were 0.030 mm, 0.030 mm, 0.060 mm and 0.060 mm, respectively.
  • the manufacturing conditions of the secondary battery of Example 2 were the same as the manufacturing conditions of the secondary battery of Example 1.
  • Example 3 a secondary battery as Example 3 was produced.
  • the amount of the insulating resin 30Z applied was adjusted so that the thicknesses T1A, T1B, T2, and T3 of the gaskets 30 were 0.030 mm, 0.030 mm, 0.075 mm, and 0.075 mm, respectively.
  • the manufacturing conditions of the secondary battery of Example 3 were the same as the manufacturing conditions of the secondary battery of Example 1.
  • Example 4 the secondary battery of the above-described embodiment including the external terminal 20 and the lid portion 12 shown in FIG. 4 and the like was manufactured. Except for this point, the manufacturing conditions of the secondary battery of Example 4 were the same as the manufacturing conditions of the secondary battery of Example 1. Here, the amount of the insulating resin 30Z applied was adjusted so that the thicknesses T1A, T1B, T2 and T3 of the gaskets 30 were 0.030 mm, 0.030 mm, 0.045 mm and 0.045 mm, respectively.
  • Comparative Example 1 a secondary battery including the gasket 130 shown in FIG. 15 was produced.
  • the gasket 130 has a first portion 131 sandwiched between the surface 12S and the facing surface 20S, a second portion 132 continuous with the first portion 131 on the side of the outer peripheral surface 20T, and a first portion 132 on the side of the inner peripheral surface 12T. 131 and a continuous third portion 133 .
  • First portion 131 has a thickness T1A and a thickness T1B.
  • the thickness T1A is the thickness of the first portion 131 at the position closest to the inclined surface 20T1 in the facing surface 20S.
  • the thickness T1B is the thickness of the first portion 131 at a position of the opposing surface 20S that is closest to the inclined surface 12T1. Also, the second portion 132 has a thickness T2 and the third portion 133 has a thickness T3.
  • the application amount of the insulating resin 30Z was adjusted so that the thicknesses T1A, T1B, T2, and T3 of the gasket 130 were all 0.030 mm. Except for this point, the manufacturing conditions of the secondary battery of Comparative Example 1 were the same as the manufacturing conditions of the secondary battery of Example 1.
  • Comparative Example 2 a secondary battery including the gasket 130 shown in FIG. 16 was manufactured.
  • the gasket 130 has a first portion 131 sandwiched between the surface 12S and the facing surface 20S, a second portion 132 continuous with the first portion 131 on the side of the outer peripheral surface 20T, and a first portion 132 on the side of the inner peripheral surface 12T. 131 and a continuous third portion 133 .
  • First portion 131 has a thickness T1A and a thickness T1B.
  • the thickness T1A is the thickness of the first portion 131 at the position closest to the inclined surface 20T1 in the facing surface 20S.
  • the thickness T1B is the thickness of the first portion 131 at a position of the opposing surface 20S that is closest to the inclined surface 12T1. Also, the second portion 132 has a thickness T2 and the third portion 133 has a thickness T3.
  • the application amount of the insulating resin 30Z was adjusted so that the thicknesses T1A, T1B, T2, and T3 of the gasket 130 were all 0.030 mm. Except for this point, the manufacturing conditions of the secondary battery of Comparative Example 2 were the same as the manufacturing conditions of the secondary battery of Example 4.
  • Table 1 describes the capacity retention rate, which is an index for evaluating cycle characteristics.
  • Table 1 also shows the presence or absence of the inclined surface 20T1 of the external terminal and the inclined surface 12T1 of the lid portion, and the thicknesses T1A, T1B, Each dimension (mm) of T2 and T3 is also described.
  • the discharge capacity (first cycle discharge capacity) was measured by discharging the secondary battery in the same environment.
  • constant current discharge was performed at a current of 3C until the voltage reached 3.0V.
  • 3C is a current value that can discharge the battery capacity in 10/3 hours.
  • the secondary battery was repeatedly charged and discharged in the same environment until the number of cycles reached 500, thereby measuring the discharge capacity (discharge capacity at the 500th cycle).
  • the charging/discharging conditions for the second and subsequent cycles were the same as the charging/discharging conditions for the first cycle.
  • capacity retention rate (%) (discharge capacity at 500th cycle/discharge capacity at 1st cycle) x 100. .
  • the second portion and the third portion that are continuous with the first portion are at least part of the outer peripheral surface of the external terminal and the inside of the through hole of the exterior member. It was found that the airtightness of the inside of the exterior member can be improved by contacting at least part of the peripheral surface. That is, it was confirmed that the secondary battery of the present disclosure can exhibit stable performance over a long period of time.
  • the outer can is a welded can (crimpless can)
  • the configuration of the outer can is not particularly limited, it may be a crimped can that has been crimped.
  • this crimped can the storage part and the lid part which are separated from each other are crimped to each other through a gasket.
  • the element structure of the battery element is not particularly limited. ) may be folded in a zigzag manner, or other element structures such as a ninety-nine fold type.
  • the electrode reactant is lithium has been described, but the electrode reactant is not particularly limited.
  • the electrode reactants may be other alkali metals such as sodium and potassium, or alkaline earth metals such as beryllium, magnesium and calcium, as described above.
  • the electrode reactant may be other light metals such as aluminum.

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  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Sealing Battery Cases Or Jackets (AREA)
PCT/JP2022/025502 2021-07-20 2022-06-27 二次電池 Ceased WO2023002807A1 (ja)

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Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2005056648A (ja) * 2003-08-01 2005-03-03 Hitachi Maxell Ltd 密閉型電池
WO2015115557A1 (ja) * 2014-01-29 2015-08-06 株式会社 東芝 電池及び封口体ユニット
JP2017004640A (ja) * 2015-06-05 2017-01-05 株式会社東芝 二次電池
CN112563556A (zh) * 2020-12-24 2021-03-26 惠州市超聚电池有限公司 纽扣电池封装结构及纽扣电池

Family Cites Families (3)

* Cited by examiner, † Cited by third party
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KR102885306B1 (ko) * 2019-08-19 2025-11-11 삼성에스디아이 주식회사 이차 전지
CN212434722U (zh) * 2020-06-03 2021-01-29 珠海冠宇电池股份有限公司 扣式电池及电子设备
CN112002834A (zh) * 2020-06-12 2020-11-27 珠海市讯达科技有限公司 一种纽扣电池及其制作方法

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2005056648A (ja) * 2003-08-01 2005-03-03 Hitachi Maxell Ltd 密閉型電池
WO2015115557A1 (ja) * 2014-01-29 2015-08-06 株式会社 東芝 電池及び封口体ユニット
JP2017004640A (ja) * 2015-06-05 2017-01-05 株式会社東芝 二次電池
CN112563556A (zh) * 2020-12-24 2021-03-26 惠州市超聚电池有限公司 纽扣电池封装结构及纽扣电池

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