WO2024181012A1 - 二次電池および電池パック - Google Patents

二次電池および電池パック Download PDF

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Publication number
WO2024181012A1
WO2024181012A1 PCT/JP2024/003382 JP2024003382W WO2024181012A1 WO 2024181012 A1 WO2024181012 A1 WO 2024181012A1 JP 2024003382 W JP2024003382 W JP 2024003382W WO 2024181012 A1 WO2024181012 A1 WO 2024181012A1
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WO
WIPO (PCT)
Prior art keywords
electrode
winding body
negative electrode
positive electrode
secondary battery
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/JP2024/003382
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English (en)
French (fr)
Japanese (ja)
Inventor
創一 山口
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
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Filing date
Publication date
Application filed by Murata Manufacturing Co Ltd filed Critical Murata Manufacturing Co Ltd
Priority to DE112024001050.4T priority Critical patent/DE112024001050T5/de
Priority to JP2025503675A priority patent/JPWO2024181012A1/ja
Publication of WO2024181012A1 publication Critical patent/WO2024181012A1/ja
Priority to US19/091,030 priority patent/US20250226492A1/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
    • H01M50/102—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
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/058—Construction or manufacture
    • H01M10/0587—Construction or manufacture of accumulators having only wound construction elements, i.e. wound positive electrodes, wound negative electrodes and wound separators
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/04—Construction or manufacture in general
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/04—Construction or manufacture in general
    • H01M10/0431—Cells with wound or folded electrodes
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/42—Methods or arrangements for servicing or maintenance of secondary cells or secondary half-cells
    • H01M10/425—Structural combination with electronic components, e.g. electronic circuits integrated to the outside of the casing
    • 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
    • H01M50/20—Mountings; Secondary casings or frames; Racks, modules or packs; Suspension devices; Shock absorbers; Transport or carrying devices; Holders
    • H01M50/204—Racks, modules or packs for multiple batteries or multiple cells
    • H01M50/207—Racks, modules or packs for multiple batteries or multiple cells characterised by their shape
    • H01M50/213—Racks, modules or packs for multiple batteries or multiple cells characterised by their shape adapted 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
    • H01M50/50—Current conducting connections for cells or batteries
    • H01M50/531—Electrode connections inside a battery casing
    • H01M50/538—Connection of several leads or tabs of wound or folded electrode stacks

Definitions

  • This disclosure relates to a secondary battery and a battery pack including the same.
  • Patent Document 1 proposes a secondary battery that employs a so-called tabless structure to reduce internal resistance and enable charging and discharging at a relatively large current.
  • the secondary battery of one embodiment of the present disclosure includes an electrode winding and a battery can.
  • the electrode winding is formed by stacking a positive electrode and a negative electrode with a separator interposed therebetween and winding the electrode winding around a central axis.
  • the battery can has a generally cylindrical outer shape with the height direction along the central axis, and contains the electrode winding.
  • the battery can has a container and a lid.
  • the container has a lower end portion closed by a bottom portion, and an upper end portion located opposite the lower end portion in the height direction and including an opening through which the electrode winding can be inserted.
  • the lid portion closes the opening of the container.
  • the flatness of the upper part of the electrode winding is greater than the flatness of the lower part of the electrode winding. Since the flatness of the lower part of the electrode winding is relatively small, the electrode winding is easily inserted into the battery can during the assembly work of the secondary battery. Furthermore, since the flatness of the upper part of the electrode winding is large, the electrode winding is less likely to move inside the battery can even when the secondary battery is subjected to vibration. As a result, damage to the electrode winding itself and damage to the connection part between the positive electrode current collector plate joined to the electrode winding and the external terminal (lid part) can be prevented. Therefore, according to the secondary battery of the embodiment of the present disclosure, excellent vibration resistance can be ensured without impairing manufacturability.
  • FIG. 1 is a cross-sectional view illustrating a configuration of a secondary battery according to an embodiment of the present disclosure.
  • FIG. 2 is a schematic diagram showing an example of the configuration of a laminate including the positive electrode, the negative electrode, and the separator shown in FIG.
  • FIG. 3 is a vertical sectional view showing one example of the vertical sectional structure of the electrode winding body shown in FIG.
  • FIG. 4A is a development view of the positive electrode shown in FIG.
  • FIG. 4B is a cross-sectional view of the positive electrode shown in FIG.
  • FIG. 5A is a development view of the negative electrode shown in FIG.
  • FIG. 5B is a cross-sectional view of the negative electrode shown in FIG.
  • FIG. 6A is a plan view of the positive electrode current collector plate shown in FIG. FIG.
  • FIG. 6B is a plan view of the negative electrode current collector plate shown in FIG.
  • FIG. 7A is a horizontal cross-sectional view that typically illustrates the horizontal cross-sectional structure of the upper part of the electrode winding body shown in FIG. 1 .
  • 7B is a horizontal cross-sectional view that typically illustrates the horizontal cross-sectional structure of the lower part of the electrode winding body shown in FIG. 1.
  • FIG. 8 is a perspective view illustrating a manufacturing process of the secondary battery shown in FIG.
  • FIG. 9 is a block diagram showing a circuit configuration of a battery pack to which the secondary battery according to one embodiment of the present disclosure is applied.
  • Secondary battery 1-1 Configuration 1-2. Operation 1-3. Manufacturing method 1-4. Actions and effects 2.
  • a cylindrical lithium ion secondary battery having a cylindrical exterior shape will be described as an example.
  • the secondary battery disclosed herein is not limited to a cylindrical lithium ion secondary battery, and may be a lithium ion secondary battery having an exterior shape other than cylindrical, or may be a battery using an electrode reactant other than lithium.
  • the principle of charging and discharging a secondary battery is not particularly limited, but below, a case will be described in which battery capacity is obtained by utilizing the absorption and release of an electrode reactant.
  • This secondary battery has a positive electrode, a negative electrode, and an electrolyte.
  • the charge capacity of the negative electrode is larger than the discharge capacity of the positive electrode.
  • 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, it is a light metal such as an alkali metal or an alkaline earth metal.
  • Alkaline metals include lithium, sodium, and potassium, while alkaline earth metals include beryllium, magnesium, and calcium.
  • the electrode reactant is lithium.
  • a secondary battery that obtains battery capacity by utilizing the absorption and release of lithium is known as a lithium-ion secondary battery.
  • lithium-ion secondary battery lithium is absorbed and released in an ionic state.
  • Fig. 1 shows a cross-sectional structure along the height direction of a lithium ion secondary battery 1 (hereinafter simply referred to as secondary battery 1) according to this embodiment.
  • the secondary battery 1 shown in Fig. 1 includes an outer can 11 having a cylindrical outer shape as a battery can, and an electrode winding body 20 as a battery element housed in the outer can 11.
  • the cylindrical shape referred to here is not limited to a shape having a circular cross section perpendicular to the height direction, but also includes a shape having an elliptical cross section perpendicular to the height direction.
  • the secondary battery 1 includes an outer tube 50 covering the outer peripheral surface of the outer can 11.
  • the secondary battery 1 includes, for example, a pair of insulating plates 12, 13, an electrode winding body 20, a positive electrode current collector 24, and a negative electrode current collector 25 inside an outer can 11.
  • the electrode winding body 20 is, for example, a structure in which a positive electrode 21 and a negative electrode 22 are stacked and wound with a separator 23 interposed therebetween.
  • the electrode winding body 20 is impregnated with an electrolyte solution, which is a liquid electrolyte.
  • the secondary battery 1 may further include, inside the outer can 11, one or more of a positive temperature coefficient (PTC) element and a reinforcing member.
  • PTC positive temperature coefficient
  • the outer can 11 has a hollow cylindrical structure in which the lower end in the Z-axis direction, which is the height direction, is closed and the upper end is open. Therefore, the upper end of the outer can 11 is an open end 11N, and the lower end of the outer can 11 is closed by a bottom part 11B that is substantially disk-shaped. Between the open end 11N and the bottom part 11B is a side wall part 11W that surrounds the electrode winding body 20.
  • the material of the outer can 11 includes, for example, a metal material such as iron. However, the surface of the outer can 11 may be plated with a metal material such as nickel.
  • the insulating plate 12 and the insulating plate 13 are disposed, for example, opposite each other in the Z-axis direction so as to sandwich the electrode winding body 20 between them.
  • the open end 11N and its vicinity are sometimes referred to as the upper part of the secondary battery 1, and the part where the outer can 11 is closed and its vicinity are sometimes referred to as the lower part of the secondary battery 1.
  • the open end 11N of the outer can 11 is closed by a battery cover 14 (described later).
  • the exterior tube 50 surrounds the side surface 11WS1 which is the outer surface of the side wall portion 11W of the exterior can 11. However, as shown in Fig. 1, the exterior tube 50 may cover the folded portion 11P (described later) at the upper end portion of the exterior can 11. The exterior tube 50 may also cover a part of the bottom surface 11BS which is the outer surface of the bottom portion 11B of the exterior can 11.
  • the exterior tube 50 is made of a heat-shrinkable insulating film containing, for example, a polyester resin, a polyamide resin, a thermoplastic elastomer resin, or the like.
  • a washer 55 is provided in the gap between the exterior tube 50 and the folded portion 11P of the exterior can 11.
  • the washer 55 is an insulating ring member having an opening 55K in a central region in a plane perpendicular to the height direction.
  • a protrusion 14T in the central region of the battery lid 14 is inserted into the opening 55K.
  • the washer 55 can be made of, for example, black modified polyphenylene ether.
  • Each of the insulating plates 12 and 13 is, for example, a dish-shaped plate having a surface perpendicular to the central axis CL of the electrode winding body 20, i.e., a surface perpendicular to the Z-axis in Fig. 1.
  • the insulating plates 12 and 13 are arranged so as to sandwich the electrode winding body 20 therebetween.
  • a crimped structure 11R At the open end 11N of the exterior can 11, for example, a structure in which the battery lid 14 and the safety valve mechanism 30 are crimped via a gasket 15, i.e., a crimped structure 11R, is formed.
  • the exterior can 11 is hermetically sealed by the battery lid 14 with the electrode winding body 20 and the like housed inside the exterior can 11.
  • the crimped structure 11R is a so-called crimp structure, and has a bent portion 11P as a so-called crimp portion.
  • the battery lid 14 is a closing member that mainly closes the open end 11N when the electrode winding body 20 and the like are housed inside the exterior can 11.
  • the battery lid 14 contains, for example, the same material as the material from which the exterior can 11 is formed.
  • a convex portion 14T that protrudes upward (in the +Z direction) is provided in the central region of the battery lid 14.
  • the peripheral region of the battery lid 14 other than the central region is in contact with, for example, the safety valve mechanism 30.
  • the gasket 15 is a sealing member that is mainly interposed between the folded portion 11P of the outer can 11 and the battery lid 14.
  • the gasket 15 seals the gap between the folded portion 11P and the battery lid 14.
  • the surface of the gasket 15 may be coated with, for example, asphalt.
  • the gasket 15 contains, for example, one or more types of insulating materials.
  • the type of insulating material is not particularly limited, but may be, for example, a polymer material such as polybutylene terephthalate (PBT) and polypropylene (PP). Among them, the insulating material is preferably polybutylene terephthalate. This is because the gap between the folded portion 11P and the battery lid 14 is sufficiently sealed while electrically isolating the outer can 11 and the battery lid 14 from each other.
  • the safety valve mechanism 30 is mainly configured to release the internal pressure by releasing the sealed state of the outer can 11 as necessary when the pressure (internal pressure) inside the outer can 11 increases.
  • the internal pressure of the outer can 11 increases due to, for example, gas generated due to a decomposition reaction of the electrolyte during charging and discharging.
  • the internal pressure of the outer can 11 may also increase due to heating from the outside.
  • the electrode winding body 20 is a power generating element that causes charge/discharge reactions to proceed, and is housed inside the exterior can 11.
  • the electrode winding body 20 includes a positive electrode 21, a negative electrode 22, a separator 23, and an electrolytic solution that is a liquid electrolyte.
  • the electrode winding body 20 is a development view of the electrode winding body 20, and is a schematic representation of a part of the laminate S20 including the positive electrode 21, the negative electrode 22, and the separator 23.
  • the positive electrode 21 and the negative electrode 22 are laminated with the separator 23 interposed therebetween.
  • the separator 23 has, for example, two base materials, that is, the first separator member 23A and the second separator member 23B. Therefore, the electrode winding body 20 has a four-layer laminate S20 in which the positive electrode 21, the first separator member 23A, the negative electrode 22, and the second separator member 23B are laminated in this order.
  • the positive electrode 21, the first separator member 23A, the negative electrode 22, and the second separator member 23B are all approximately strip-shaped members with the W-axis direction as the short side direction and the L-axis direction as the long side direction.
  • the electrode winding body 20 is formed by winding the laminate S20 around a central axis CL extending in the Z-axis direction so that the laminate S20 forms a spiral shape in a horizontal cross section perpendicular to the Z-axis direction. At this time, the laminate S20 is wound in a position in which the W-axis direction is approximately aligned with the Z-axis direction.
  • FIG. 3 shows an example of a configuration along a horizontal cross section perpendicular to the Z-axis direction in the electrode winding body 20. However, in FIG. 3, the separator 23 is omitted from the illustration in order to improve visibility.
  • the electrode winding body 20 has an overall appearance of a substantially cylindrical shape.
  • a through hole 26 is formed in the center of the electrode winding body 20 as an internal space.
  • the through hole 26 is a hole for inserting a winding core for assembling the electrode winding body 20 and an electrode rod for welding.
  • the positive electrode 21, the negative electrode 22, and the separator 23 are wound so that the separator 23 is disposed at the outermost circumference of the electrode winding body 20 and the innermost circumference of the electrode winding body 20.
  • the negative electrode 22 is disposed outside the positive electrode 21 at the outermost circumference of the electrode winding body 20. That is, as shown in FIG. 3, the positive electrode outermost portion 21out located at the outermost circumference of the positive electrode 21 included in the electrode winding body 20 is disposed inside the negative electrode outermost portion 22out located at the outermost circumference of the negative electrode 22 included in the electrode winding body 20.
  • the positive electrode outermost portion 21out is the outermost portion of the positive electrode 21 in the electrode winding body 20 for one revolution.
  • the negative electrode outermost portion 22out is the outermost portion of the negative electrode 22 in the electrode winding body 20 for one revolution.
  • the negative electrode 22 is disposed inside the positive electrode 21 at the innermost circumference of the electrode winding body 20. That is, as shown in FIG. 3, the negative electrode innermost portion 22in located at the innermost circumference of the negative electrode 22 included in the electrode winding body 20 is located inside the positive electrode innermost portion 21in located at the innermost circumference of the positive electrode 21 included in the electrode winding body 20.
  • the positive electrode innermost portion 21in is the innermost portion of the positive electrode 21 in the electrode winding body 20.
  • the negative electrode innermost portion 22in is the innermost portion of the negative electrode 22 in the electrode winding body 20.
  • the number of turns of each of the positive electrode 21, the negative electrode 22, and the separator 23 is not particularly limited and can be set arbitrarily.
  • FIG. 4A is an exploded view of the positive electrode 21, and is a schematic representation of the state before being wound.
  • FIG. 4B shows the cross-sectional configuration of the positive electrode 21. Note that FIG. 4B shows a cross section taken along line IVB-IVB shown in FIG. 4A.
  • the positive electrode 21 includes, for example, a positive electrode collector 21A and a positive electrode active material layer 21B provided on the positive electrode collector 21A.
  • the positive electrode active material layer 21B may be provided on only one side of the positive electrode collector 21A, or on both sides of the positive electrode collector 21A.
  • FIG. 4B shows the case where the positive electrode active material layer 21B is provided on both sides of the positive electrode collector 21A.
  • the positive electrode current collector 21A includes a positive electrode current collector inner peripheral surface 21A1 facing the winding center side of the electrode winding body 20, i.e., the central axis CL, and a positive electrode current collector outer peripheral surface 21A2 facing the opposite side of the winding center side of the electrode winding body 20, i.e., the opposite side of the positive electrode current collector inner peripheral surface 21A1.
  • the positive electrode 21 has, as the positive electrode active material layer 21B, a positive electrode inner peripheral side active material layer 21B1 covering at least a part of the positive electrode current collector inner peripheral surface 21A1, and a positive electrode outer peripheral side active material layer 21B2 covering at least a part of the positive electrode current collector outer peripheral surface 21A2.
  • the positive electrode inner peripheral side active material layer 21B1 and the positive electrode outer peripheral side active material layer 21B2 may be collectively referred to as the positive electrode active material layer 21B without distinguishing between them.
  • the positive electrode 21 has a positive electrode covering portion 211 in which the positive electrode collector 21A is covered with a positive electrode active material layer 21B, and a positive electrode exposed portion 212 in which the positive electrode collector 21A is exposed without being covered with the positive electrode active material layer 21B.
  • the positive electrode covering portion 211 and the positive electrode exposed portion 212 each extend along the L-axis direction, which is the longitudinal direction of the positive electrode 21, from the central axis side edge 21E1 of the positive electrode 21 to the outer peripheral edge 21E2 of the positive electrode 21.
  • the L-axis direction corresponds to the winding direction of the electrode winding body 20.
  • the positive electrode collector 21A is covered with the positive electrode active material layer 21B from the central axis side edge 21E1 of the positive electrode 21 to the outer peripheral edge 21E2 of the positive electrode 21 in the winding direction of the electrode winding body 20.
  • the positive electrode covering portion 211 and the positive electrode exposed portion 212 are adjacent to each other in the W-axis direction, which is the short side direction of the positive electrode 21.
  • the W-axis direction substantially coincides with the central axis CL. As shown in FIG.
  • the central axis side edge 21E1 of the positive electrode innermost circumferential portion 21in is located in a position receding inward from the central axis side edge 22E1 of the negative electrode innermost circumferential portion 22in.
  • the positive electrode 21 further has a lower edge 21E3 extending in the L-axis direction at the lower side of the electrode winding body 20.
  • An insulating layer 101 may be provided near the boundary between the positive electrode covering portion 211 and the positive electrode exposed portion 212.
  • the insulating layer 101 may extend from the central axis side edge 21E1 to the outer peripheral side edge 21E2 of the electrode winding body 20, similar to the positive electrode covering portion 211 and the positive electrode exposed portion 212.
  • the insulating layer 101 may be bonded to at least one of the first separator member 23A and the second separator member 23B. This is because it is possible to prevent the occurrence of misalignment between the positive electrode 21 and the separator 23.
  • the insulating layer 101 may include a resin containing polyvinylidene fluoride (PVDF). By containing PVDF, the insulating layer 101 may swell due to, for example, a solvent contained in the electrolyte, and may be well bonded to the separator 23. The detailed configuration of the positive electrode 21 will be described later.
  • FIG. 5A is an exploded view of the negative electrode 22, and is a schematic representation of the state before being wound.
  • FIG. 5B shows the cross-sectional configuration of the negative electrode 22. Note that FIG. 5B shows a cross section taken along line VB-VB shown in FIG. 5A.
  • the negative electrode 22 includes, for example, a negative electrode collector 22A and a negative electrode active material layer 22B provided on the negative electrode collector 22A.
  • the negative electrode active material layer 22B may be provided on only one side of the negative electrode collector 22A, or on both sides of the negative electrode collector 22A.
  • FIG. 5B shows the case where the negative electrode active material layer 22B is provided on both sides of the negative electrode collector 22A.
  • the negative electrode current collector 22A includes a negative electrode current collector inner peripheral surface 22A1 facing the winding center side of the electrode winding body 20, i.e., the central axis CL, and a negative electrode current collector outer peripheral surface 22A2 facing the opposite side to the winding center side of the electrode winding body 20, i.e., the opposite side of the negative electrode current collector inner peripheral surface 22A1.
  • the negative electrode 22 has, as the negative electrode active material layer 22B, a negative electrode inner peripheral side active material layer 22B1 covering at least a part of the negative electrode current collector inner peripheral surface 22A1, and a negative electrode outer peripheral side active material layer 22B2 covering at least a part of the negative electrode current collector outer peripheral surface 22A2.
  • the negative electrode inner peripheral side active material layer 22B1 and the negative electrode outer peripheral side active material layer 22B2 may be collectively referred to as the negative electrode active material layer 22B without distinguishing between them.
  • the negative electrode 22 has a negative electrode covering portion 221 in which the negative electrode collector 22A is covered with the negative electrode active material layer 22B, and a negative electrode exposed portion 222 in which the negative electrode collector 22A is exposed without being covered with the negative electrode active material layer 22B.
  • the negative electrode covering portion 221 and the negative electrode exposed portion 222 each extend along the L-axis direction, which is the longitudinal direction of the negative electrode 22.
  • the negative electrode exposed portion 222 extends from the central axis side edge 22E1 to the outer peripheral edge 22E2 of the negative electrode 22 in the winding direction of the electrode winding body 20.
  • the negative electrode covering portion 221 is not provided on the central axis side edge 22E1 and the outer peripheral edge 22E2 of the negative electrode 22.
  • a part of the negative electrode exposed portion 222 is formed so as to sandwich the negative electrode covering portion 221 in the L-axis direction, which is the longitudinal direction of the negative electrode 22.
  • the negative electrode exposed portion 222 includes a first portion 222A, a second portion 222B, and a third portion 222C.
  • the negative electrode 22 further has a lower edge 22E3 extending in the L-axis direction at the lower side of the electrode winding body 20.
  • the first portion 222A is provided adjacent to the negative electrode covering portion 221 in the W-axis direction, and extends in the L-axis direction from the central axis side edge 22E1 to the outer periphery side edge 22E2 of the negative electrode 22.
  • the second portion 222B and the third portion 222C are provided to sandwich the negative electrode covering portion 221 in the L-axis direction.
  • the first portion 222A is located near the lower edge 22E3 of the negative electrode 22.
  • the second portion 222B is located, for example, near the central axis side edge 22E1 of the negative electrode 22, and the third portion 222C is located near the outer periphery side edge 22E2 of the negative electrode 22.
  • the negative electrode current collector 22A is shown as extending linearly along the W-axis direction. However, in reality, the negative electrode edge 222E of the negative electrode exposed portion 222 is bent toward the central axis CL as shown in FIG. 1 and connected to the negative electrode current collector 25. The detailed configuration of the negative electrode 22 will be described later.
  • the positive electrode 21 and the negative electrode 22 are laminated via the separator 23 so that the positive electrode exposed portion 212 and the first portion 222A of the negative electrode exposed portion 222 are oriented in opposite directions along the W-axis direction, which is the width direction.
  • the end of the separator 23 of the electrode winding body 20 is fixed by attaching a fixing tape 46 to the side portion 45, so that the winding does not become loose.
  • the width of the positive electrode exposed portion 212 is A and the width of the first portion 222A of the negative electrode exposed portion 222 is B
  • C the width of the portion of the positive electrode exposed portion 212 that protrudes from the outer edge of the separator 23 in the width direction
  • D the length of the first portion 222A of the negative electrode exposed portion 222 that protrudes from the outer edge of the separator 23 on the opposite side in the width direction
  • the width D 3 (mm).
  • a plurality of adjacent positive electrode edges 212E in the radial direction (R direction) of the electrode winding body 20 are bent toward the central axis CL so as to overlap with each other, forming the upper end surface 41 of the electrode winding body 20.
  • a plurality of adjacent negative electrode edges 222E in the radial direction (R direction) are bent toward the central axis CL so as to overlap with each other, forming the lower end surface 42 of the electrode winding body 20.
  • the plurality of positive electrode edges 212E of the positive electrode exposed portion 212 are gathered at the upper end surface 41 of the electrode winding body 20, and the plurality of negative electrode edges 222E of the negative electrode exposed portion 222 are gathered at the lower end surface 42 of the electrode winding body 20.
  • the positive electrode edge 212E is bent toward the central axis CL to have a flat surface.
  • the negative electrode edge 222E is bent toward the central axis CL to have a flat surface.
  • the flat surface here does not only mean a completely flat surface, but also includes a surface that has some unevenness or surface roughness to the extent that the positive electrode exposed portion 212 and the negative electrode exposed portion 222 can be joined to the positive electrode current collector 24 and the negative electrode current collector 25, respectively.
  • the positive electrode collector 21A is made of, for example, aluminum foil, as described later.
  • the negative electrode collector 22A is made of, for example, copper foil, as described later.
  • the positive electrode collector 21A is softer than the negative electrode collector 22A. That is, the Young's modulus of the positive electrode exposed portion 212 is lower than that of the negative electrode exposed portion 222. For this reason, in one embodiment, it is more preferable that the widths A to D have a relationship of A>B and C>D.
  • the heights measured from the tip of the separator 23 at the folded portions may be approximately the same for the positive electrode 21 and the negative electrode 22.
  • the multiple positive electrode edges 212E (FIG. 1) of the positive electrode exposed portion 212 are folded and overlap moderately. Therefore, the positive electrode exposed portion 212 and the positive electrode collector plate 24 can be easily joined.
  • the negative electrode edges 222E (FIG. 1) of the negative electrode exposed portion 222 are folded and overlap each other to a certain extent. This allows the negative electrode exposed portion 222 and the negative electrode current collector plate 25 to be easily joined together.
  • the joining here means that they are joined together by, for example, laser welding, but the joining method is not limited to laser welding.
  • the portion of the positive electrode exposed portion 212 of the positive electrode 21 that faces the negative electrode 22 across the separator 23 is covered with an insulating layer 101.
  • the insulating layer 101 has a width of, for example, 3 mm in the W-axis direction.
  • the insulating layer 101 covers the entire area of the positive electrode exposed portion 212 of the positive electrode 21 that faces the negative electrode covering portion 221 of the negative electrode 22 via the separator 23.
  • the insulating layer 101 can effectively prevent an internal short circuit of the secondary battery 1, for example, when a foreign object enters between the negative electrode covering portion 221 and the positive electrode exposed portion 212.
  • the insulating layer 101 absorbs the impact and can effectively prevent bending of the positive electrode exposed portion 212 and short circuit between the positive electrode exposed portion 212 and the negative electrode 22.
  • the secondary battery 1 may further have insulating tapes 53, 54 in the gap between the exterior can 11 and the electrode winding body 20.
  • the positive electrode exposed portion 212 and the negative electrode exposed portion 222 gathered at the upper end surface 41 and the lower end surface 42 are conductors such as bare metal foil. Therefore, if the positive electrode exposed portion 212 and the negative electrode exposed portion 222 are close to the exterior can 11, a short circuit may occur between the positive electrode 21 and the negative electrode 22 through the exterior can 11.
  • the insulating tapes 53, 54 are provided as insulating members.
  • the insulating tapes 53, 54 are, for example, adhesive tapes whose base layer is made of any one of polypropylene, polyethylene terephthalate, and polyimide, and whose base layer has an adhesive layer on one side.
  • the insulating tapes 53, 54 are positioned so as not to overlap with the fixing tape 46 attached to the side portion 45, and the thickness of the insulating tapes 53, 54 is set to be equal to or less than the thickness of the fixing tape 46.
  • the positive electrode current collector 24 is arranged to face the upper end face 41 and the negative electrode current collector 25 is arranged to face the lower end face 42, and the positive electrode covering portion 211 present on the upper end face 41 and the positive electrode current collector 24 are welded at multiple points, and the negative electrode covering portion 221 present on the lower end face 42 and the negative electrode current collector 25 are welded at multiple points.
  • the internal resistance of the secondary battery 1 is reduced.
  • the fact that the upper end face 41 and the lower end face 42 are flat as described above also contributes to the reduction in resistance.
  • the positive electrode current collector 24 is electrically connected to the battery cover 14, for example, via the safety valve mechanism 30.
  • the negative electrode current collector 25 is electrically connected to, for example, the exterior can 11.
  • Fig. 6A is a schematic diagram showing an example of the configuration of the positive electrode current collector 24.
  • Fig. 6B is a schematic diagram showing an example of the configuration of the negative electrode current collector 25.
  • the positive electrode current collector 24 is a metal plate made of, for example, aluminum or an aluminum alloy, or a composite material thereof.
  • the negative electrode current collector 25 is a metal plate made of, for example, nickel, a nickel alloy, copper, or a copper alloy, or a composite material of two or more of these.
  • the positive electrode current collector 24 has a shape in which a substantially rectangular band-shaped portion 32 is connected to a substantially fan-shaped sector portion 31.
  • a through hole 35 is formed near the center of the sector portion 31.
  • the positive electrode current collector 24 is provided so that the through hole 35 overlaps with the through hole 26 in the Z-axis direction.
  • the portion indicated by diagonal lines in FIG. 6A is the insulating portion 32A of the band-shaped portion 32.
  • the insulating portion 32A is a part of the band-shaped portion 32 to which an insulating tape is attached or an insulating material is applied.
  • the portion of the band-shaped portion 32 below the insulating portion 32A is the connection portion 32B to the sealing plate, which also serves as an external terminal. As shown in FIG.
  • the band-shaped portion 32 is less likely to come into contact with the portion of the negative electrode potential. Therefore, the positive electrode current collector 24 does not need to have the insulating portion 32A. If the positive electrode current collector 24 does not have an insulating portion 32A, the charge/discharge capacity can be increased by widening the width between the positive electrode 21 and the negative electrode 22 by an amount equivalent to the thickness of the insulating portion 32A.
  • the shape of the negative current collector 25 shown in FIG. 6B is almost the same as the shape of the positive current collector 24 shown in FIG. 6A.
  • the band-shaped portion 34 of the negative current collector 25 is different from the band-shaped portion 32 of the positive current collector 24.
  • the band-shaped portion 34 of the negative current collector 25 is shorter than the band-shaped portion 32 of the positive current collector 24, and does not have a portion corresponding to the insulating portion 32A of the positive current collector 24.
  • the band-shaped portion 34 is provided with a round protrusion 37 indicated by multiple circles. During resistance welding, the current is concentrated in the protrusion 37, which melts and welds the band-shaped portion 34 to the bottom of the outer can 11.
  • the negative current collector 25 has a through hole 36 formed near the center of the sector portion 33. In the secondary battery 1, the negative electrode current collector 25 is arranged so that the through hole 36 overlaps with the through hole 26 in the Z-axis direction.
  • the sectorial portion 31 of the positive electrode current collector 24 covers only a portion of the upper end face 41 due to its planar shape.
  • the sectorial portion 33 of the negative electrode current collector 25 covers only a portion of the lower end face 42 due to its planar shape.
  • the positive electrode current collector 21A contains a conductive material such as aluminum, etc.
  • the positive electrode current collector 21A is, for example, a metal foil made of aluminum or an aluminum alloy.
  • the positive electrode active material layer 21B contains, as a positive electrode active material, one or more types of positive electrode materials capable of absorbing and releasing lithium. However, the positive electrode active material layer 21B further contains a positive electrode binder.
  • the positive electrode material may contain one or more of other materials such as an adhesive and a positive electrode conductive material.
  • the positive electrode material is preferably a lithium-containing compound, more specifically a lithium-containing composite.
  • Lithium-containing composite oxides are preferably lithium-containing oxides and lithium-containing phosphate compounds.
  • Lithium-containing composite oxides are oxides that contain lithium and one or more other elements, i.e., elements other than lithium, as constituent elements.
  • the lithium-containing composite oxide has, for example, a crystal structure of either a layered rock salt type or a spinel type.
  • the lithium-containing phosphate compound is a compound containing lithium and one or more other elements.
  • the positive electrode active material layer 21B is a phosphate compound containing lithium cobalt oxide, lithium nickel cobalt manganese oxide, and the like as a positive electrode active material. It is preferable that the electrolyte contains at least one of lithium nickel cobalt aluminum oxide.
  • the positive electrode binder contains, for example, one or more of synthetic rubbers and polymer compounds. Examples of synthetic rubbers include styrene-butadiene rubbers, fluorine-based rubbers, and ethylene-propylene-diene rubbers.
  • the polymer compound is, for example, polyvinylidene fluoride, polyimide, etc.
  • the positive electrode conductive agent contains, for example, one or more of carbon materials.
  • the carbon material is, Examples of the positive electrode conductive agent include graphite, carbon black, acetylene black, and ketjen black.
  • the positive electrode conductive agent may be a metal material or a conductive polymer, etc., so long as it is a material having electrical conductivity.
  • the negative electrode current collector 22A contains a conductive material such as copper.
  • the negative electrode current collector 22A is a metal foil made of nickel, a nickel alloy, copper, or a copper alloy.
  • the surface of the negative electrode active material layer 22B is preferably roughened. This is because the adhesion of the negative electrode active material layer 22B to the negative electrode current collector 22A is improved by a so-called anchor effect. In this case, at least the negative electrode active material layer It is sufficient that the surface of the negative electrode current collector 22A is roughened in the region facing the negative electrode current collector 22B.
  • the surface roughening method is, for example, a method of forming fine particles by utilizing an electrolytic treatment. In the electrolytic process, fine particles are formed on the surface of the negative electrode current collector 22A by electrolysis in an electrolytic bath, so that the surface of the negative electrode current collector 22A has irregularities. , called electrolytic copper foil.
  • the negative electrode active material layer 22B contains, as a negative electrode active material, one or more types of negative electrode materials capable of absorbing and releasing lithium.
  • the negative electrode active material layer 22B is Furthermore, the negative electrode may contain one or more of other materials such as a negative electrode binder and a negative electrode conductive material.
  • the negative electrode material is, for example, a carbon material. This is because the change in the crystal structure is very small, so that a high energy density can be stably obtained.
  • the carbon material also functions as a negative electrode conductive agent, so that the conductivity of the negative electrode active material layer 22B is improved.
  • the carbon material may be, for example, graphitizable carbon, non-graphitizable carbon, graphite, etc.
  • the plane spacing of the (002) plane in the non-graphitizable carbon is 0.37 nm or more.
  • the interplanar spacing of the (002) plane in graphite is preferably 0.34 nm or less.
  • the carbon material is, for example, pyrolytic carbon, cokes, glassy carbon fiber, organic polymer compound calcined bodies, activated carbon, and carbon blacks.
  • the cokes include pitch coke, These include needle coke and petroleum coke.
  • Sintered organic polymer compounds are made by sintering (carbonizing) polymer compounds such as phenolic resin and furan resin at an appropriate temperature.
  • the carbon material may be low-crystalline carbon that has been heat-treated at a temperature of about 1000° C. or less, or may be amorphous carbon.
  • the carbon material may be in the form of any of fibers, spheres, particles, and scales.
  • the open circuit voltage when fully charged i.e., the battery voltage
  • the same positive electrode active material is used as compared with the case where the open circuit voltage when fully charged is 4.20 V. Even if a battery is used, the amount of lithium released per unit mass is large. Therefore, the amounts of the positive electrode active material and the negative electrode active material are adjusted accordingly. This allows a high energy density to be obtained.
  • the negative electrode active material layer 22B may contain a silicon-containing material containing at least one of silicon, silicon oxide, carbon silicon compound, and silicon alloy as the negative electrode active material.
  • the silicon-containing material is a general term for materials containing silicon as a constituent element. However, the silicon-containing material may contain only silicon as a constituent element.
  • the type of silicon-containing material may be only one type or may be two or more types.
  • the silicon-containing material can form an alloy with lithium, and may be a simple substance of silicon, a silicon alloy, a silicon compound, a mixture of two or more types thereof, or a material containing one or more types of phases thereof.
  • the silicon-containing material may be crystalline or amorphous, or may contain both a crystalline portion and an amorphous portion.
  • the simple substance described here means a general simple substance, and may contain a trace amount of impurities. In other words, the purity of the simple substance is not necessarily limited to 100%.
  • the silicon alloy contains, for example, one or more of tin, nickel, copper, iron, cobalt, manganese, zinc, indium, silver, titanium, germanium, bismuth, antimony, and chromium as a constituent element other than silicon.
  • the silicon compound contains, for example, one or more of carbon and oxygen as a constituent element other than silicon.
  • the silicon compound may contain, for example, one or more of the series of constituent elements described for the silicon alloy as a constituent element other than silicon.
  • examples of silicon alloys and silicon compounds include SiB4 , SiB6 , Mg2Si , Ni2Si, TiSi2 , MoSi2 , CoSi2, NiSi2 , CaSi2 , CrSi2 , Cu5Si , FeSi2, MnSi2 , NbSi2 , TaSi2 , VSi2 , WSi2 , ZnSi2 , SiC , Si3N4 , Si2N2O , and SiOv (0 ⁇ v ⁇ 2 ), etc.
  • the range of v can be set arbitrarily, and may be, for example, 0.2 ⁇ v ⁇ 1.4.
  • the separator 23 is interposed between the positive electrode 21 and the negative electrode 22.
  • the separator 23 allows lithium ions to pass while preventing a short circuit of current caused by contact between the positive electrode 21 and the negative electrode 22.
  • the separator 23 is, for example, one or more types of porous membranes such as synthetic resins and ceramics, and may be a laminated membrane of two or more types of porous membranes.
  • the synthetic resin is, for example, polytetrafluoroethylene, polypropylene, and polyethylene.
  • the separator 23 may have a substrate made of a single-layer polyolefin porous membrane containing polyethylene. This is because good high-output characteristics can be obtained compared to a laminated membrane.
  • the thickness of the porous membrane may be, for example, 10 ⁇ m or more and 15 ⁇ m or less.
  • the thickness of the single-layered porous film made of polyolefin is 15 ⁇ m or less, better discharge capacity characteristics can be obtained.
  • the surface density of the porous film may be, for example, 6.3 g/m 2 or more and 8.3 g/m 2 or less.
  • the surface density of the single-layered porous film made of polyolefin is 6.3 g/m 2 or more, internal short circuit can be sufficiently avoided. If the surface density of the single-layered porous film made of polyolefin is 8.3 g/m 2 or less, better discharge capacity characteristics can be obtained.
  • the separator 23 may include, for example, the porous film as the substrate described above and a polymer compound layer provided on one or both sides of the substrate layer. This is because the adhesiveness of the separator 23 to each of the positive electrode 21 and the negative electrode 22 is improved, thereby suppressing distortion of the electrode winding body 20. This suppresses the decomposition reaction of the electrolyte and also suppresses leakage of the electrolyte impregnated in the substrate layer, so that the resistance is less likely to increase even when charging and discharging is repeated, and battery swelling is suppressed.
  • the polymer compound layer includes, for example, a polymer compound such as polyvinylidene fluoride. This is because it has excellent physical strength and is electrochemically stable.
  • the polymer compound may be other than polyvinylidene fluoride.
  • a solution in which a polymer compound is dissolved in an organic solvent or the like is applied to the substrate layer, and then the substrate layer is dried. Note that the substrate layer may be immersed in the solution and then dried.
  • This polymer compound layer may contain, for example, one or more types of insulating particles such as inorganic particles. Types of inorganic particles include, for example, aluminum oxide and aluminum nitride.
  • the electrolyte contains a solvent and an electrolyte salt. However, the electrolyte may further contain any one or more of other materials such as additives.
  • the solvent contains any one or more of non-aqueous solvents such as organic solvents.
  • the electrolyte containing a non-aqueous solvent is a so-called non-aqueous electrolyte.
  • the non-aqueous solvent contains, for example, a fluorine compound and a dinitrile compound.
  • the fluorine compound contains, for example, at least one of fluorinated ethylene carbonate, trifluorocarbonate, trifluoroethyl methyl carbonate, fluorinated carboxylic acid ester, and fluorine ether.
  • the non-aqueous solvent may further contain at least one of nitrile compounds other than the dinitrile compound, such as a mononitrile compound or a trinitrile compound.
  • nitrile compounds other than the dinitrile compound such as a mononitrile compound or a trinitrile compound.
  • the dinitrile compound for example, succinonitrile (SN) is preferable.
  • SN succinonitrile
  • the dinitrile compound is not limited to succinonitrile, and may be other dinitrile compounds such as adiponitrile.
  • the electrolyte salt includes, for example, one or more of salts such as lithium salt.
  • the electrolyte salt may include, for example, a salt other than lithium salt.
  • the salt other than lithium is, for example, a salt of a light metal other than lithium.
  • the lithium salt is, for example, lithium hexafluorophosphate (LiPF 6 ), lithium tetrafluoroborate (LiBF 4 ), lithium perchlorate (LiClO 4 ), lithium hexafluoroarsenate (LiAsF 6 ), lithium tetraphenylborate (LiB(C 6 H 5 ) 4 ), lithium methanesulfonate (LiCH 3 SO 3 ), lithium trifluoromethanesulfonate (LiCF 3 SO 3 ), lithium tetrachloroaluminate (LiAlCl 4 ), dilithium hexafluorosilicate (Li 2 SF 6 ), lithium chloride (LiCl), lithium bromide (LiBr), etc.
  • LiPF 6 lithium hexafluorophosphate
  • LiBF 4 lithium perchlorate
  • LiAsF 6 lithium hexafluoroarsenate
  • any one or more of lithium hexafluorophosphate, lithium tetrafluoroborate, lithium perchlorate, and lithium hexafluoroarsenate are preferred, and lithium hexafluorophosphate is more preferred.
  • the content of the electrolyte salt is not particularly limited, but is preferably 0.3 mol/kg to 3 mol/kg relative to the solvent.
  • the concentration of LiPF 6 in the electrolyte is preferably 1.25 mol/kg or more and 1.45 mol/kg or less. This is because cycle deterioration due to consumption (decomposition) of salt during high load rate charging can be prevented, and high load cycle characteristics are improved.
  • the concentration of LiBF 4 in the electrolyte is preferably 0.001 (wt%) or more and 0.1 (wt%) or less. This is because cycle deterioration due to consumption (decomposition) of salt during high-load rate charging can be more effectively prevented, thereby further improving the high-load cycle characteristics.
  • FIG. 7A and 7B each show a schematic structure of a horizontal cross section perpendicular to the central axis CL of the secondary battery 1.
  • FIG. 7A and FIG. 7B only the electrode winding body 20 and the outer can 11 are shown, and other components are omitted.
  • the electrode winding body 20 is not shown in detail, but is shown to the extent that the outer shape of the electrode winding body 20 can be recognized.
  • FIG. 7A shows a horizontal cross section of the upper part of the electrode winding body 20 in the height direction Z.
  • FIG. 7B shows a horizontal cross section of the lower part of the electrode winding body 20 in the height direction Z.
  • the upper part of the electrode winding body 20 in the height direction Z refers to any part of the part above the center point CP (FIG. 1) of the electrode winding body 20 in the height direction Z.
  • the lower part of the electrode winding body 20 in the height direction Z refers to any part of the part below the center point CP (FIG. 1) of the electrode winding body 20 in the height direction Z.
  • Fig. 7A shows a horizontal cross section at a height position Lv1 indicated by an arrow in Fig. 1.
  • Fig. 7B shows a horizontal cross section at a height position Lv2 indicated by an arrow in Fig. 1.
  • the height position Lv1 corresponds to the height position of the upper edge of the electrode winding body 20 in the height direction Z.
  • the height position Lv2 corresponds to the height position of the lower edge of the electrode winding body 20 in the height direction Z.
  • the horizontal cross-sectional shape of the outer can 11 is approximately circular. Therefore, the inner diameter D11 of the outer can 11 is substantially constant.
  • the horizontal cross-sectional shape of the electrode winding body 20 is approximately elliptical.
  • the first radial direction in which the outer diameter of the electrode winding body 20 is maximum in the horizontal cross section is defined as the radial direction R1.
  • the radial direction R1 is the up-down direction on the paper.
  • the electrode winding body 20 has a maximum diameter D20max1 along the radial direction R1.
  • the electrode winding body 20 has a minimum diameter D20min1 along the radial direction R2 (left-right direction on the paper) perpendicular to the radial direction R1.
  • D20max1-D20min1)/D20max1 is called the flatness FT1 of the electrode winding body 20 at the height position Lv1.
  • the horizontal cross-sectional shape of the electrode winding body 20 is also approximately elliptical at the bottom of the secondary battery 1.
  • the flatness FT2 of the horizontal cross-sectional shape of the electrode winding body 20 at the height position Lv2 is smaller than the flatness FT1 of the horizontal cross-sectional shape of the electrode winding body 20 at the height position Lv1.
  • the flatness FT1 of the horizontal cross-sectional shape of the electrode winding body 20 at the height position Lv1 is larger than the flatness FT2 of the horizontal cross-sectional shape of the electrode winding body 20 at the height position Lv2 (FT1>FT2).
  • the electrode winding body 20 has a maximum diameter D20max2 along the radial direction R1 at the height position Lv2.
  • the maximum diameter D20max2 at the height position Lv2 is smaller than the maximum diameter D20max1 at the height position Lv1.
  • the electrode winding body 20 has a minimum diameter D20min2 along the radial direction R2 at the height position Lv2.
  • the flatness FT2 of the electrode winding 20 at the height position Lv2 is expressed as (D20max2-D20min2)/D20max2.
  • the maximum diameter at the center point CP of the electrode winding 20 in the height direction Z is smaller than the maximum diameter D20max1 at the upper edge of the electrode winding 20 in the height direction Z, and is larger than the maximum diameter D20max2 at the lower edge of the electrode winding in the height direction Z.
  • a portion of the outer peripheral surface 20S of the electrode winding body 20 may be in contact with the inner surface 11WS2 of the side wall portion 11W of the outer can 11.
  • the maximum diameter D20max1 of the electrode winding body 20 substantially coincides with the inner diameter D11 of the outer can 11.
  • the outer peripheral surface 20S of the electrode winding body 20 is spaced from the inner surface 11WS2 of the side wall portion 11W of the outer can 11. In other words, the maximum diameter D20max2 of the electrode winding body 20 is smaller than the inner diameter D11 of the outer can 11.
  • FIG. 8 is a perspective view for explaining the manufacturing process of the secondary battery shown in Fig. 1.
  • a positive electrode collector 21A is prepared, and a positive electrode active material layer 21B is selectively formed on the surface of the positive electrode collector 21A to form a positive electrode 21 having a positive electrode coating portion 211 and a positive electrode exposed portion 212.
  • a negative electrode collector 22A is prepared, and a negative electrode active material layer 22B is selectively formed on the surface of the negative electrode collector 22A to form a negative electrode 22 having a negative electrode coating portion 221 and a negative electrode exposed portion 222.
  • a drying process may be performed on the positive electrode 21 and the negative electrode 22.
  • the positive electrode 21 and the negative electrode 22 are stacked via the first separator member 23A and the second separator member 23B so that the positive electrode exposed portion 212 and the first portion 222A of the negative electrode exposed portion 222 are opposite each other in the W-axis direction, thereby producing a laminate S20.
  • the laminate S20 is spirally wound so that a through hole 26 is formed.
  • a cylindrical winding core whose cross-sectional shape gradually changes from an ellipse to a circle along the height direction is used as a jig, and the laminate S20 is wound around the cylindrical winding core.
  • a fixing tape 46 is attached to the outermost circumference of the spirally wound laminate S20, and then the winding core is removed.
  • the electrode winding body 20 is obtained as shown in FIG. 8 (A).
  • the laminate S20 may be wound around a cylindrical winding core whose cross-sectional shape is circular, and after the winding core is removed, a light pressure may be applied to a part of the height direction of the wound laminate S20 with a jig such as a clamp, thereby obtaining an electrode winding body 20 having a predetermined flatness FT1, FT2.
  • the edge of a flat plate having a thickness of, for example, 0.5 mm is pressed perpendicularly, i.e., in the Z-axis direction, against the upper end face 41 and the lower end face 42 of the electrode winding body 20, thereby locally bending a part of the upper end face 41 and a part of the lower end face 42.
  • grooves 43 are created that extend radially from the through holes 26 in the radial direction (R direction). Note that the number and arrangement of grooves 43 shown in FIG. 8B are examples and the present disclosure is not limited thereto.
  • substantially the same pressure is applied from above and below the electrode winding body 20 in a substantially vertical direction to the upper end face 41 and the lower end face 42 at substantially the same time.
  • a rod-shaped jig for example, is inserted into the through hole 26.
  • the positive electrode exposed portion 212 and the first part 222A of the negative electrode exposed portion 222 are bent so that the upper end face 41 and the lower end face 42 are flat.
  • the positive electrode edge portion 212E of the positive electrode exposed portion 212 and the negative electrode edge portion 222E of the negative electrode exposed portion 222 at the upper end face 41 and the lower end face 42 are bent while overlapping toward the through hole 26.
  • the sector portion 31 of the positive electrode current collector 24 is joined to the upper end face 41 by laser welding or the like, and the sector portion 33 of the negative electrode current collector 25 is joined to the lower end face 42 by laser welding or the like.
  • insulating tapes 53, 54 are attached to predetermined positions of the electrode winding body 20. After that, as shown in FIG. 8 (D), the strip portion 32 of the positive current collector plate 24 is folded and the strip portion 32 is inserted into the hole 12H of the insulating plate 12. In addition, the strip portion 34 of the negative current collector plate 25 is folded and the strip portion 34 is inserted into the hole 13H of the insulating plate 13.
  • the electrode winding body 20 assembled as described above is inserted into the exterior can 11 shown in FIG. 8(E), and the bottom of the exterior can 11 is welded to the negative electrode current collector 25. Then, a narrowed portion 11S is formed near the open end 11N of the exterior can 11. Furthermore, electrolyte is injected into the exterior can 11, and the strip portion 32 of the positive electrode current collector 24 is welded to the safety valve mechanism 30.
  • the gasket 15, the safety valve mechanism 30, and the battery lid 14 are used to seal the outer can 11 using the constricted portion 11S.
  • the outer can 11 with the washer 55 attached to the battery lid 14 is covered with the outer tube 50, and the outer tube 50 is heated and shrunk, for example by applying hot air to the outer tube 50, so that the outer tube 50 is tightly attached to the outer surface of the outer can 11.
  • the flatness FT1 of the horizontal cross-sectional shape of the upper part of the electrode winding body 20 is larger than the flatness FT2 of the horizontal cross-sectional shape of the lower part of the electrode winding body 20 (FT1>FT2).
  • the flatness FT2 of the lower part of the electrode winding body 20 is smaller than the flatness FT1 of the upper part, so that the electrode winding body 20 can be easily inserted into the exterior can 11 during the assembly work of the secondary battery 1.
  • the electrode winding body 20 can be easily stored inside the exterior can 11 without interfering with the outer circumferential surface 20S of the electrode winding body 20 and the upper end part of the exterior can 11.
  • the flatness FT1 of the upper part of the electrode winding body 20 is larger than the flatness FT2 of the lower part of the electrode winding body 20
  • the outer peripheral surface 20S of the upper part of the electrode winding body 20 housed inside the exterior can 11 comes into contact with the inner surface 11WS2 of the exterior can 11.
  • the electrode winding body 20 is less likely to move inside the exterior can 11. As a result, damage to the electrode winding body 20 itself and damage to the connection part between the positive electrode current collector plate 24 joined to the electrode winding body 20 and the battery lid 14 can be prevented. Therefore, according to the secondary battery 1, excellent vibration resistance can be ensured without impairing manufacturability.
  • the secondary battery 1 employs a so-called tabless structure in which the electrode winding body 20 does not have an electrode tab extending in the height direction Z. For this reason, the electrode winding body 20 is soft and easily deformed, and the flatness of the electrode winding body 20 is easy to adjust. This is therefore suitable for realizing an electrode winding body 20 in which the horizontal cross-sectional shape of the upper part in the height direction Z differs from the horizontal cross-sectional shape of the lower part.
  • the electrode winding body 20 does not have a winding core in its center, and has a through hole 26, so in this respect too, it is suitable for realizing an electrode winding body 20 in which the horizontal cross-sectional shape of the upper part in the height direction Z differs from the horizontal cross-sectional shape of the lower part.
  • Battery pack] 9 is a block diagram showing an example of a circuit configuration in which a battery according to an embodiment of the present invention (hereinafter, referred to as a secondary battery) is applied to a battery pack 300.
  • the battery pack 300 includes a battery pack 301, an exterior, a switch unit 304 including a charge control switch 302a and a discharge control switch 303a, a current detection resistor 307, a temperature detection element 308, and a control unit 310.
  • the battery pack 300 has a positive terminal 321 and a negative terminal 322, and when charging, the positive terminal 321 and the negative terminal 322 are connected to the positive terminal and the negative terminal of the charger, respectively, and charging is performed. When the electronic device is in use, the positive terminal 321 and the negative terminal 322 are connected to the positive terminal and the negative terminal of the electronic device, respectively, and discharging is performed.
  • the battery pack 301 is made up of multiple secondary batteries 301a connected in series or parallel.
  • the secondary batteries 1 described above can be used as the secondary batteries 301a.
  • FIG. 9 shows an example in which six secondary batteries 301a are connected in 2 parallel and 3 series (2P3S), any other connection method may be used, such as n parallel and m series (n and m are integers).
  • the switch unit 304 includes a charge control switch 302a and a diode 302b, as well as a discharge control switch 303a and a diode 303b, and is controlled by the control unit 310.
  • the diode 302b has a polarity in the reverse direction to the charge current flowing from the positive terminal 321 to the battery pack 301, and a polarity in the forward direction to the discharge current flowing from the negative terminal 322 to the battery pack 301.
  • the diode 303b has a polarity in the forward direction to the charge current and a polarity in the reverse direction to the discharge current. Note that although the switch unit 304 is provided on the + side in FIG. 9, it may be provided on the - side.
  • the charge control switch 302a is controlled by the charge/discharge control unit so that it is turned off when the battery voltage reaches the overcharge detection voltage and so that no charging current flows in the current path of the assembled battery 301. After the charge control switch 302a is turned off, only discharging is possible through the diode 302b. In addition, it is controlled by the control unit 310 so that it is turned off when a large current flows during charging and so that the charging current flows in the current path of the assembled battery 301 is cut off.
  • the discharge control switch 303a is controlled by the control unit 310 so that it is turned off when the battery voltage reaches the overdischarge detection voltage and so that no discharging current flows in the current path of the assembled battery 301.
  • the discharge control switch 303a After the discharge control switch 303a is turned off, only charging is possible through the diode 303b. In addition, it is controlled by the control unit 310 so that it is turned off when a large current flows during discharging and so that the discharging current flows in the current path of the assembled battery 301 is cut off.
  • the temperature detection element 308 is, for example, a thermistor that is provided near the battery pack 301 and measures the temperature of the battery pack 301 and supplies the measured temperature to the control unit 310.
  • the voltage detection unit 311 measures the voltage of the battery pack 301 and each of the secondary batteries 301a that make it up, A/D converts the measured voltage, and supplies it to the control unit 310.
  • the current measurement unit 313 measures the current using a current detection resistor 307, and supplies this measured current to the control unit 310.
  • the switch control unit 314 controls the charge control switch 302a and the discharge control switch 303a of the switch unit 304 based on the voltage and current input from the voltage detection unit 311 and the current measurement unit 313.
  • the switch control unit 314 sends a control signal to the switch unit 304 to prevent overcharging, overdischarging, and overcurrent charging and discharging.
  • the overcharge detection voltage is set to, for example, 4.20V ⁇ 0.05V
  • the overdischarge detection voltage is set to, for example, 2.4V ⁇ 0.1V.
  • the charge and discharge switches can be semiconductor switches such as MOSFETs.
  • the parasitic diodes of the MOSFETs function as diodes 302b and 303b.
  • switch control section 314 supplies control signals DO and CO to the gates of charge control switch 302a and discharge control switch 303a, respectively.
  • charge control switch 302a and discharge control switch 303a are P-channel types, they are turned ON by a gate potential that is lower than the source potential by a predetermined value or more. That is, in normal charge and discharge operations, control signals CO and DO are at a low level, and charge control switch 302a and discharge control switch 303a are turned ON.
  • control signals CO and DO are set to a high level, and the charge control switch 302a and the discharge control switch 303a are set to the OFF state.
  • Memory 317 is made up of RAM or ROM, such as non-volatile memory such as EPROM (Erasable Programmable Read Only Memory). Numerical values calculated by control unit 310 and the internal resistance value of each secondary battery 301a in its initial state measured during the manufacturing process are stored in memory 317 in advance, and can also be rewritten as appropriate. In addition, by storing the fully charged capacity of secondary battery 301a, it is possible to calculate, for example, the remaining capacity together with control unit 310.
  • the temperature detection unit 318 measures the temperature using the temperature detection element 308, and performs charge/discharge control in the event of abnormal heat generation, and performs corrections when calculating the remaining capacity.
  • the secondary battery according to the embodiment of the present disclosure described above can be mounted on devices such as electronic devices, electric vehicles, electric aircraft, and power storage devices, or can be used to supply power.
  • Electronic devices include, for example, notebook computers, smartphones, tablet devices, PDAs (personal digital assistants), mobile phones, wearable devices, cordless phone handsets, video movie players, digital still cameras, e-books, electronic dictionaries, music players, radios, headphones, game consoles, navigation systems, memory cards, pacemakers, hearing aids, power tools, electric shavers, refrigerators, air conditioners, televisions, stereos, hot water heaters, microwave ovens, dishwashers, washing machines, dryers, lighting equipment, toys, medical equipment, robots, road conditioners, and traffic lights.
  • PDAs personal digital assistants
  • mobile phones wearable devices
  • cordless phone handsets video movie players
  • digital still cameras digital still cameras
  • e-books electronic dictionaries
  • music players radios
  • headphones game consoles
  • navigation systems memory cards
  • pacemakers hearing aids
  • power tools electric shavers, refrigerators, air conditioners, televisions, stereos, hot water heaters, microwave ovens, dishwashers, washing machines, dryers, lighting equipment, toys, medical equipment
  • examples of electric vehicles include railroad cars, golf carts, electric carts, and electric cars (including hybrid cars), and the battery is used as a driving power source or auxiliary power source for these vehicles.
  • Examples of power storage devices include power sources for storing electricity in buildings such as homes, or for power generation facilities.
  • Example 1-1 to 1-4 Comparative Examples 1-1 to 1-4
  • the cylindrical secondary batteries shown in Fig. 1 and the like were fabricated, and the dimensions of the fabricated secondary batteries were then measured.
  • lithium ion secondary batteries having nominal dimensions of 21 mm in diameter and 70 mm in length were fabricated.
  • an aluminum foil having a thickness of 12 ⁇ m was prepared as the positive electrode collector 21A.
  • a layered lithium oxide having a Ni ratio of 85% or more in lithium nickel cobalt aluminum oxide (NCA) as a positive electrode active material, a positive electrode binder made of polyvinylidene fluoride, and a conductive assistant containing a mixture of carbon black, acetylene black, and ketjen black were mixed to obtain a positive electrode mixture.
  • the mixture ratio of the positive electrode active material, the positive electrode binder, and the conductive assistant was 96.4:2:1.6.
  • the positive electrode mixture was added to an organic solvent (N-methyl-2-pyrrolidone), and the organic solvent was stirred to prepare a paste-like positive electrode mixture slurry.
  • the positive electrode mixture slurry was applied to predetermined areas on both sides of the positive electrode collector 21A using a coating device, and the positive electrode mixture slurry was then dried to form the positive electrode active material layer 21B.
  • a paint containing polyvinylidene fluoride (PVDF) was applied to the surface of the positive electrode exposed portion 212 adjacent to the positive electrode covering portion 211, and dried to form an insulating layer 101 having a width of 3 mm and a thickness of 8 ⁇ m. Then, the positive electrode active material layer 21B was compression molded using a roll press.
  • a positive electrode 21 having a positive electrode covering portion 211 and a positive electrode exposed portion 212 was obtained. Then, the positive electrode 21 was sheared to set the width of the positive electrode covering portion 211 in the W-axis direction to 60 mm, and the width of the positive electrode exposed portion 212 in the W-axis direction to 7 mm. In addition, the length of the positive electrode 21 in the L-axis direction was set to 1700 mm.
  • a copper foil with a thickness of 8 ⁇ m was prepared as the negative electrode current collector 22A.
  • a negative electrode active material made of a mixture of carbon material made of graphite and SiO, a negative electrode binder made of polyvinylidene fluoride, and a conductive assistant made of a mixture of carbon black, acetylene black, and ketjen black were mixed to obtain a negative electrode mixture.
  • the mixing ratio of the negative electrode active material, the negative electrode binder, and the conductive assistant was 96.1:2.9:1.0.
  • the mixing ratio of graphite and SiO in the negative electrode active material was 95:5.
  • the negative electrode mixture was added to an organic solvent (N-methyl-2-pyrrolidone), and the organic solvent was stirred to prepare a paste-like negative electrode mixture slurry.
  • the negative electrode mixture slurry was applied to predetermined regions on both sides of the negative electrode current collector 22A using a coating device, and the negative electrode mixture slurry was then dried to form the negative electrode active material layer 22B.
  • the negative electrode active material layer 22B was compression molded using a roll press. In this manner, the negative electrode 22 having the negative electrode covering portion 221 and the negative electrode exposed portion 222 was obtained.
  • the negative electrode 22 was sheared to set the width of the negative electrode covering portion 221 in the W-axis direction to 62 mm, and the width of the first portion 222A of the negative electrode exposed portion 222 in the W-axis direction to 4 mm.
  • the length of the negative electrode 22 in the L-axis direction was set to 1760 mm.
  • the laminate S20 was produced by stacking the positive electrode 21 and the negative electrode 22 via the first separator member 23A and the second separator member 23B so that the positive electrode exposed portion 212 and the first portion 222A of the negative electrode exposed portion 222 were opposite each other in the W-axis direction. At that time, the laminate S20 was produced so that the positive electrode active material layer 21B did not protrude from the negative electrode active material layer 22B in the W-axis direction. As shown in Table 1 below, the laminate S20 was produced so that the first distance L1 and the second distance L2 were each 3 mm. As the first separator member 23A and the second separator member 23B, a polyethylene sheet having a width of 65 mm and a thickness of 14 ⁇ m was used.
  • the laminate S20 was spirally wound so that the through holes 26 were formed, and a fixing tape 46 was attached to the outermost circumference of the wound laminate S20.
  • the electrode wound body 20 was obtained. Pressure was applied to the ends of the obtained electrode winding 20 in the width direction from the outer periphery of the electrode winding 20 toward the winding center of the electrode winding 20, so that the predetermined flatnesses FT1 and FT2 were achieved.
  • substantially the same pressure was applied from above and below the electrode winding body 20 in a direction substantially perpendicular to the upper end face 41 and the lower end face 42 at substantially the same time.
  • the positive electrode exposed portion 212 and the first portion 222A of the negative electrode exposed portion 222 were folded, respectively, and the upper end face 41 and the lower end face 42 were made flat.
  • the positive electrode edge portion 212E of the positive electrode exposed portion 212 and the negative electrode edge portion 222E of the negative electrode exposed portion 222 at the upper end face 41 and the lower end face 42 were folded while overlapping toward the through hole 26.
  • the sector portion 31 of the positive electrode current collector 24 was joined to the upper end face 41 by laser welding, and the sector portion 33 of the negative electrode current collector 25 was joined to the lower end face 42 by laser welding.
  • insulating tapes 53, 54 are attached to the electrode winding body 20 at predetermined positions, and then the belt-shaped portion 32 of the positive electrode current collector 24 is folded to insert the belt-shaped portion 32 into the hole 12H of the insulating plate 12, and the belt-shaped portion 34 of the negative electrode current collector 25 is folded to insert the belt-shaped portion 34 into the hole 13H of the insulating plate 13.
  • the electrode winding body 20 assembled as described above was inserted into the outer can 11, and the bottom of the outer can 11 and the negative electrode current collector 25 were welded together.
  • the inner diameter D11 of the outer can 11 used was 20.80 ⁇ 0.05 mm.
  • a narrowed portion 11S was formed near the open end 11N of the outer can 11.
  • the electrolyte was injected into the outer can 11, and the strip portion 32 of the positive electrode current collector 24 was welded together with the safety valve mechanism 30.
  • the electrolyte used was a solvent containing ethylene carbonate (EC) and dimethyl carbonate (DMC) as the main solvent, to which fluoroethylene carbonate (FEC) and succinonitrile (SN) were added, and LiBF4 and LiPF6 were used as electrolyte salts.
  • EC ethylene carbonate
  • DMC dimethyl carbonate
  • FEC fluoroethylene carbonate
  • SN succinonitrile
  • LiBF4 and LiPF6 were used as electrolyte salts.
  • the respective contents (wt%) of EC, DMC, FEC, SN, LiBF4 , and LiPF6 in the electrolyte were 12.7:56.2:12.0:1.0:1.0:17.1.
  • the gasket 15, the safety valve mechanism 30, and the battery lid 14 were used to seal the battery lid 14. Finally, the exterior can 11 with the washer 55 attached to the battery lid 14 was covered with the exterior tube 50, and the exterior tube 50 was heated and shrunk by applying hot air to the exterior tube 50, for example, and the exterior tube 50 was tightly attached to the outer surface of the exterior can 11.
  • the maximum diameter D20max1 and the minimum diameter D20min1 of the upper part of the electrode winding body 20, and the maximum diameter D20max2 and the minimum diameter D20min2 of the lower part of the electrode winding body 20 were measured. Specifically, the outer diameter of an image of the electrode winding body 20 projected two-dimensionally was measured using an outer diameter measuring device of a two-dimensional projection type while rotating the electrode winding body 20 about its central axis as the rotation axis.
  • the maximum diameter and the minimum diameter in the horizontal cross section of the electrode winding body 20 at the height position Lv1 shown in FIG. 1 were taken as the maximum diameter D20max1 and the minimum diameter D20min1, respectively.
  • the maximum diameter and the minimum diameter in the horizontal cross section of the electrode winding body 20 at the height position Lv2 shown in FIG. 1 were taken as the maximum diameter D20max2 and the minimum diameter D20min2, respectively.
  • the outer diameter of the electrode winding body 20 taken out by disassembling the secondary battery was measured.
  • the reason why the maximum diameter D20max1 of the upper portion of Example 1-3 is larger than the diameter D11 without the outer can 11 is that the negative electrode active material layer 22B expands due to charging and discharging.
  • the maximum diameter D11 without the outer can 11 of Example 1-3 also increases accordingly.
  • a drum test was performed to measure the change in impedance.
  • each secondary battery was taken out, and the open circuit voltage (OCV) and impedance of each secondary battery taken out were measured.
  • the vibration test was performed until the impedance value after the vibration was applied greatly exceeded the initial impedance and was judged to be unsuccessful.
  • the application of vibration gradually separates the joint between the lid and the positive electrode current collector plate, and the impedance increases. Therefore, the longer the time for which vibration is applied until the impedance increases, the higher the vibration resistance can be evaluated.
  • the present disclosure has been described above with reference to one embodiment and examples, but the configuration of the present disclosure is not limited to the configuration described in the embodiment and examples, and can be modified in various ways.
  • the above embodiment and examples have been described using a secondary battery with a so-called tabless structure as an example, but the secondary battery of the present disclosure is not limited to this, and can also be applied to a secondary battery with a so-called tab structure.
  • the electrode reactant is lithium, but the electrode reactant is not particularly limited. Therefore, as described above, the electrode reactant may be other alkali metals such as sodium and potassium, or alkaline earth metals such as beryllium, magnesium, and calcium. In addition, the electrode reactant may be other light metals such as aluminum.
  • the present disclosure may take the following forms. ⁇ 1> an electrode winding body in which a positive electrode and a negative electrode are stacked with a separator interposed therebetween and wound around a central axis; a battery can having a cylindrical outer shape with a height direction along the central axis and housing the electrode winding body, The battery can is a container having a lower end portion closed by a bottom portion and an upper end portion located on the opposite side to the lower end portion in the height direction and including an opening through which the electrode winding body can be inserted; a lid portion that closes the opening of the container,
  • a secondary battery wherein when the ratio of the maximum diameter of the electrode winding body to the minimum diameter of the electrode winding body is defined as the flatness of the electrode winding body, the flatness of at least a portion of an upper part of the electrode winding body is greater than the flatness of at least a portion of a lower part of the electrode winding body.
  • ⁇ 2> The secondary battery according to ⁇ 1>, wherein the flatness of the electrode winding body at an upper end edge in the height direction is greater than the flatness of the electrode winding body at a lower end edge in the height direction.
  • ⁇ 3> The secondary battery according to the above item ⁇ 1> or ⁇ 2>, wherein a maximum diameter of the electrode winding body is substantially equal to an inner diameter of the battery can.
  • ⁇ 4> The secondary battery described in any one of ⁇ 1> to ⁇ 3> above, wherein a maximum diameter at a center point in the height direction of the electrode winding body is smaller than a maximum diameter at an upper end edge of the electrode winding body in the height direction and is larger than a maximum diameter at a lower end edge of the electrode winding body in the height direction.
  • ⁇ 5> The secondary battery according to any one of ⁇ 1> to ⁇ 4>, wherein a through hole is provided in a center of the electrode winding body.
  • ⁇ 6> The secondary battery according to any one of ⁇ 1> to ⁇ 5>, wherein a part of an upper portion of the electrode winding body is in contact with an inner surface of the container.
  • ⁇ 7> The secondary battery according to any one of ⁇ 1> to ⁇ 6> above, wherein a maximum diameter of an upper part of the electrode winding body is larger than a maximum diameter of a lower part of the electrode winding body.
  • ⁇ 8> a positive electrode current collector plate disposed to face a first end surface in the height direction of the electrode winding body; a negative electrode current collector plate disposed to face a second end surface of the electrode winding body opposite to the first end surface in the height direction, the positive electrode has a positive electrode covering portion in which a positive electrode current collector is covered with a positive electrode active material layer, and a positive electrode exposed portion in which the positive electrode current collector is not covered with the positive electrode active material layer and is joined to the positive electrode current collector, the negative electrode has a negative electrode covering portion in which a negative electrode current collector is covered with a negative electrode active material layer, and a negative electrode exposed portion in which the negative electrode current collector is not covered with the negative electrode active material layer and is exposed and joined to the negative electrode current collector,

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PCT/JP2024/003382 2023-02-27 2024-02-02 二次電池および電池パック Ceased WO2024181012A1 (ja)

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CN120902246A (zh) * 2025-10-09 2025-11-07 河北高明电缆有限公司 一种电缆绝缘挤出设备

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JP2000100464A (ja) * 1998-09-25 2000-04-07 Fuji Photo Film Co Ltd 巻回体の缶挿入方法および装置
JP2004220862A (ja) * 2003-01-10 2004-08-05 Sony Corp 非水電解質電池及びその製造方法
CN113131008A (zh) * 2021-04-13 2021-07-16 宁波超霸能源有限公司 卷绕品成型方法

Patent Citations (3)

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Publication number Priority date Publication date Assignee Title
JP2000100464A (ja) * 1998-09-25 2000-04-07 Fuji Photo Film Co Ltd 巻回体の缶挿入方法および装置
JP2004220862A (ja) * 2003-01-10 2004-08-05 Sony Corp 非水電解質電池及びその製造方法
CN113131008A (zh) * 2021-04-13 2021-07-16 宁波超霸能源有限公司 卷绕品成型方法

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Publication number Priority date Publication date Assignee Title
CN120902246A (zh) * 2025-10-09 2025-11-07 河北高明电缆有限公司 一种电缆绝缘挤出设备

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