JP5294247B2 - Non-aqueous electrolyte battery - Google Patents

Description

  The present invention relates to a non-aqueous electrolyte battery having an electrode wound body obtained by winding a sheet-like positive electrode and a sheet-like negative electrode via a sheet-like separator as a battery element.

  Known examples of non-aqueous electrolyte batteries using this type of electrode winding as a battery element include Patent Document 1 and Patent Document 2 by the present applicant. In the non-aqueous electrolyte battery described in Patent Document 1, an electrode winding body obtained by winding a sheet-like positive electrode having a large thickness and a short thickness together with a negative electrode and a separator is used as a battery element, and a cylindrical exterior The surface of the electrode winding body is covered with a metal foil so that the electrode winding body can be smoothly inserted into the can. In the non-aqueous electrolyte battery described in Patent Document 2, in order to obtain a non-aqueous electrolyte battery having a high capacity and excellent pulse discharge characteristics, the thickness dimension of the sheet-like positive electrode is specified, and at least one of the sheet-like negative electrodes is provided. A lithium-aluminum alloy is disposed in the part.

  The lithium-aluminum alloy according to the negative electrode of Patent Document 2 can be formed by laminating an aluminum foil on the surface of a metal lithium foil and electrochemically alloying it in the battery. Since such a lithium-aluminum alloy is pulverized, the surface area of the sheet-like negative electrode can be increased. Moreover, since the lithium-aluminum alloy has a lower reactivity with the electrolytic solution than lithium, formation of an organic film can be suppressed, and deterioration of battery characteristics due to this can be suppressed. However, such a pulverized lithium-aluminum alloy is easy to fall off due to vibration or collision (hereinafter referred to as “powder falling”). There was a disadvantage to cause.

  As a conventionally known countermeasure against powder falling, it is conceivable that a separator is formed in a bag shape and a negative electrode or a positive electrode is accommodated in the bag-shaped separator as in Patent Document 3. If such a countermeasure is applied to a non-aqueous electrolyte battery as in Patent Document 2, it is considered that fine powder of lithium-aluminum alloy can be prevented from leaking out of the bag from the upper and lower surfaces of the bag-shaped separator.

Japanese Patent Laying-Open No. 2004-342452 (FIG. 1-2) JP 2007-250414 A (FIGS. 1-2) JP 63-308866 A (FIG. 1)

  However, since it is not easy to accommodate the negative electrode or the positive electrode in the bag-shaped separator, it takes time and labor to manufacture the electrode winding body. In the case of a bag-like separator, the separator is likely to wrinkle when it is wound, and the separator may not be wound properly.

  The present invention has been made in order to solve the problems of the conventional nonaqueous electrolyte battery as described above, and its purpose is that the positive and negative active materials that have fallen out come into contact with the other positive and negative electrodes. In addition to preventing the battery characteristics from being deteriorated, it is possible to reduce the labor and time for manufacturing the electrode winding body and to obtain an appropriate winding state of the separator.

In the present invention, as shown in FIGS. 1 and 2, a sheet-like positive electrode 3 and a sheet-like negative electrode 4 are wound through a sheet-like separator 5 in a bottomed cylindrical outer can 2 having an upper opening. A cylindrical non-aqueous electrolyte battery in which the wound electrode winding body 6 is accommodated is an object. The electrode winding body 6 is formed by a cover portion 30 that extends along the upper and lower end surfaces of the electrode winding body 6 by deforming the upper and lower end portions 29a and 29b of the separator 5 in a wound state. the upper and lower ends of the positive and negative electrodes 3, 4 is that covered. The separator 5 is configured by overlapping a nonwoven fabric 28 and a microporous film 29. The vertical width dimension of the microporous film 29 is larger than the vertical width dimension of the nonwoven fabric 28, and the upper and lower end portions of the microporous film 29 are in the vertical direction than the upper and lower end portions of the nonwoven fabric 28, respectively. Located outside of. Then, the cover portion 30 is formed by the upper and lower end portions 29 a and 29 b of the microporous film 29. In addition, the case where the cover part 30 does not cover at least one outermost peripheral part among the positive and negative electrodes 3 and 4 of the electrode winding body 6 is included here.

  The microporous film 29 of the separator 5 is made of a thermoplastic resin, and the upper and lower end portions 29a and 29b of the wound microporous film 29 are heated and deformed to form the cover portion 30. It can be. The melting point of the microporous film 29 of the separator 5 is desirably lower than the melting point of the nonwoven fabric 28.

  The cover 30 can be formed by thermally welding the upper and lower end portions 29a and 29b of the inner peripheral side and the outer peripheral side of the winding in the microporous film 29 of the separator 5. Here, the case where only a part of the upper and lower end portions 29a and 29b of the microporous film 29 is thermally welded is also included.

  When the upper and lower ends of the positive and negative electrodes 3 and 4 are covered by the cover portion 30 of the separator 5 as in the present invention, the negative electrode active material and the like that have fallen off from the negative electrode 4 wrap around the upper and lower ends of the separator 5 to form the positive electrode 3. There is no possibility that the positive electrode active material or the like that has fallen off from the positive electrode 3 wraps around the upper and lower ends of the separator 5 and reaches the negative electrode 4. Thus, the dropped negative electrode active material can be prevented from reacting with the positive electrode active material of the positive electrode 3, and the dropped positive electrode active material can be prevented from reacting with the negative electrode active material of the negative electrode 4. It is possible to reliably reduce the occurrence of defects such as deterioration.

  Further, according to the present invention, the cover 30 is formed by deforming the upper and lower end portions of the separator 5 in the wound state. For example, the separator is formed in a bag shape before the winding, and the positive electrode is connected to the bag-like separator. 3 and the negative electrode 4 can be prevented from wrinkling of the separator 5 that occurs when the negative electrode 4 is accommodated and wound, whereby an appropriate winding state of the separator 5 can be obtained. In the present invention, the positive electrode 3, the negative electrode 4, and the separator 5 are wound by a normal method, and then the upper and lower ends of the separator 5 after the winding are respectively deformed so that the upper and lower ends of the positive and negative electrodes 3 and 4 are Since it covers, compared with the case where the positive electrode 3 and the negative electrode 4 are accommodated in the aforementioned bag-shaped separator, the change in the manufacturing process can be reduced, and it is difficult to accommodate the positive electrode 3 and the negative electrode 4 in the bag-shaped separator. There is no work, and labor and time for manufacturing the electrode winding body 6 can be reduced.

  When the cover portion 30 is formed by the upper and lower end portions 29a and 29b of the microporous film 29 located on the outer side in the vertical direction from the upper and lower ends of the nonwoven fabric 28, the fine powder of the active material is less likely to permeate than the nonwoven fabric 28. Since the upper and lower ends of the positive and negative electrodes 3 and 4 are covered with the microporous film 29, the active material and the like that have fallen off from the positive and negative electrodes 3 and 4 permeate through the cover 30 of the separator 5 and the other positive and negative electrodes 3 and 4 The risk of reaching 4 is further reduced.

  When the cover portion 30 is formed by heating and deforming the upper and lower end portions 29 a and 29 b of the thermoplastic microporous film 29, for example, the heated hot plates 31 and 32 are attached to the microporous film 29. The cover 30 can be formed simply by pressing against the upper and lower ends 29a and 29b, and the electrode winding body 6 of the present invention can be easily manufactured.

  When the melting point of the microporous film 29 of the separator 5 is lower than the melting point of the nonwoven fabric 28, the microporous film 29 is deformed by heating while suppressing adverse effects on the properties of the nonwoven fabric 28 due to the heating. Can do. That is, changes in properties such as clogging of the nonwoven fabric 28 due to the heating can be reduced.

  When the upper and lower ends 29a and 29b of the inner peripheral side and the outer peripheral side of the winding in the microporous film 29 of the separator 5 are heat-welded, the upper and lower end portions 29a and 29b of the inner peripheral side and the outer peripheral side of the winding Is firmly coupled, and the shape retention of the cover 30 is enhanced. Therefore, the negative electrode active material dropped from the negative electrode 4 goes around the upper and lower ends of the separator 5 to reach the positive electrode 3, or the positive electrode active material dropped from the positive electrode 3 goes around the upper and lower ends of the separator 5 to the negative electrode 4. Can be surely prevented. Thereby, the reliability of the present nonaqueous electrolyte battery is improved.

  1 to 8 show a nonaqueous electrolyte battery according to an embodiment of the present invention. 2 and 4, the nonaqueous electrolyte battery 1 includes a bottomed cylindrical outer can 2 having an upper opening, a sheet-like positive electrode 3, and a sheet-like negative electrode 4 through a sheet-like separator 5. The electrode winding body 6 is a non-aqueous electrolyte (hereinafter simply referred to as an electrolyte) and a sealing structure that seals the upper opening of the outer can 2. The electrode winding body 6 is accommodated in the outer can 2 together with the electrolytic solution, and is formed in a substantially cylindrical shape as a whole. The outer can 2 is made of iron, iron alloy, or the like. The nonaqueous electrolyte battery 1 has, for example, an outer diameter dimension of 17 mm and a height dimension of 45 mm.

  The sealing structure includes a cover plate 8 fixed to the inner peripheral edge of the upper opening of the outer can 2, and a terminal body 10 attached to an opening provided in the center of the cover plate 8 via a rubber insulating packing 9. And an insulating plate 11 disposed below the lid plate 8. The insulating plate 11 is formed in a round plate shape that opens upward with an annular side wall 13 standing on the periphery of a disk-shaped base portion 12, and a gas inlet 14 is opened at the center of the base portion 12. The cover plate 8 is fixed to the inner peripheral edge of the upper opening of the outer can 2 with a crimp seal through laser welding or packing while being received by the upper end of the side wall 13 of the insulating plate 11. The lid 8 or the can bottom 2a of the outer can 2 is provided with a thin vent (not shown), and when the battery internal pressure rises, the vent is cleaved to release the battery internal pressure. The positive electrode 3 of the electrode winding body 6 and the lower surface of the terminal body 10 are connected by a positive electrode lead body 15.

  The positive electrode 3 of the wound electrode body 6 includes two strip-shaped positive electrode sheets (positive electrode active material layers) 20 and 21 having the same thickness dimension, and a strip-shaped positive electrode current collector interposed between the positive electrode sheets 20 and 21. Body 22. Each of the positive electrode sheets 20 and 21 is prepared by, for example, rolling a positive electrode mixture formed by adding a conductive assistant or a binder to a positive electrode active material and adding water or the like as necessary, and drying and pulverizing the mixture. Then, it is rolled again and formed into a sheet having a thickness of about 0.67 mm. Examples of the positive electrode active material include manganese dioxide, carbon fluoride, lithium cobalt composite oxide, and spinel type lithium composite oxide. Examples of the conductive aid include one or more composites selected from graphite, carbon black, acetylene black, ketjen black, and the like. As the binder, polytetrafluoroethylene (PVDF) or a rubber-based binder can be used.

  As the positive electrode current collector 22, a plain woven wire mesh made of stainless steel such as SUS316, SUS430, or SUS444, an expanded metal, a lath mesh, a punching metal, a metal foil (plate), or the like can be used. A paste-like conductive material is applied to the surface of the positive electrode current collector 22. Examples of the conductive material include copper paste and carbon paste. As the binder for the conductive material, it is preferable to use a heat-resistant material such as water glass or an imide binder because the positive electrode sheets 20 and 21 are dried at a high temperature exceeding 200 ° C. The thickness dimension of the positive electrode current collector 22 is about 0.1 to 0.4 mm, and the vertical width dimension of the positive electrode 3 is 37.5 mm. The positive electrode sheets 20 and 21 and the positive electrode current collector 22 are wound in a state in which only the winding start end S on the axial center side of the electrode winding body 6 is fixed.

  The negative electrode 4 of the wound electrode body 6 is a strip shape in which two thin foil (plate) negative electrode sheets (negative electrode active material layers) 24 and 25 having the same thickness dimension and both negative electrode sheets 24 and 25 are fixed. Negative electrode current collector 26. Each of the negative electrode sheets 24 and 25 is formed by forming metallic lithium into a sheet shape having a thickness dimension of 0.22 mm. As the negative electrode current collector 26, a metal foil made of copper, nickel, iron, stainless steel, or the like can be used. The vertical width dimension of each negative electrode sheet 24 and 25 is 37 mm. The thickness dimension of the negative electrode current collector 26 is 10 μm, and the vertical width dimension of the negative electrode current collector 26 is 38 mm.

  As shown in FIG. 2, the negative electrode current collector 26 is folded at the axial center of the electrode winding body 6 so that the negative electrode sheets 24 and 25 are located on the inner peripheral side and the outer peripheral side, and overlaps the two layers. And wound in the overlapped state. The negative electrode sheets 24 and 25 on the inner peripheral side and the outer peripheral side of the two-layer negative electrode current collector 26 face the positive electrode sheets 20 and 21, respectively. In the wound state, one negative electrode sheet 24 facing the positive electrode sheet 20 on the inner peripheral side has a winding end 24 a of the negative electrode sheet 24 extending more outward in the winding direction than the winding end E of the positive electrode sheet 20. . In the other negative electrode sheet 25 facing the positive electrode sheet 21 on the outer peripheral side, the winding end 25 a of the negative electrode sheet 25 extends more outward in the winding direction than the winding end E of the positive electrode sheet 21.

  As shown in FIG. 3, among the negative electrode current collectors 26 stacked on the two layers, one negative electrode current collector part 26 a to which one negative electrode sheet 24 is fixed is wound around one negative electrode sheet 24. It extends outward in the winding direction from the end 24a. As shown in FIG. 2, the winding terminal side of the negative electrode current collector portion 26b on the other side, to which the other negative electrode sheet 25 is fixed, is more outward in the winding direction than the winding terminal 25a of the other negative electrode sheet 25. The electrode winding body 6 is wound so as to cover the outermost periphery of the electrode winding body 6 in a double manner. Then, the outermost peripheral surface on the winding end side of the negative electrode current collector portion 26 b on the other side contacts over the entire area in the circumferential direction of the inner surface of the outer can 2, and the negative electrode 4 is conducted to the outer can 2.

  A fine powder lithium-aluminum alloy layer is formed as a part of the negative electrode active material layer on the surface of the negative electrode sheets 24 and 25 (the surface opposite to the negative electrode current collector 26 side). In order to form such a lithium-aluminum alloy layer, as shown in FIGS. 5 and 7, aluminum foils 27 are respectively disposed on the surfaces of the negative electrode sheets 24 and 25 before winding. The thickness dimension of the aluminum foil 27 is preferably 3 to 20 μm. The vertical width dimension of the aluminum foil 27 is preferably smaller than the vertical width dimension of the negative electrode sheets 24 and 25. Then, when the wound electrode body 6 is accommodated in the outer can 2 and the electrolytic solution is accommodated in the outer can 2, the metal lithium of the negative electrode sheets 24 and 25 and the aluminum foil 27 react electrochemically. Thus, a fine powder lithium-aluminum alloy layer is formed on the surface of each of the negative electrode sheets 24 and 25. The particle size of the fine powder of the lithium-aluminum alloy layer is 5 to 100 μm.

  As shown in FIG. 7, the separator 5 is configured by overlapping a nonwoven fabric 28 and a microporous film 29, and is folded along the surface of the negative electrode sheets 24 and 25 at the axial center of the electrode winding body 6. (See FIG. 2). The separator 5 is disposed so that the nonwoven fabric 28 is on the positive electrode 3 side and the microporous film 29 is on the negative electrode 4 side.

  As shown in FIG. 2 and FIG. 3, among the folded separators 5, one separator portion 5 a interposed between the inner peripheral positive electrode sheet 20 and one negative electrode sheet 24 is one negative electrode sheet. The extension dimension of the separator end portion 5c extending from the winding end 24a of 24 is set to 15 mm or more. The separator terminal portion 5c is interposed between the negative electrode current collector portion 26b on the other side, which is wound twice in the outermost periphery of the electrode winding body 6, and the winding terminal of one negative electrode sheet 24 It extends to a position facing 24a (see FIG. 3).

  The separator portion 5b on the other side interposed between the positive electrode sheet 21 on the outer peripheral side and the other negative electrode sheet 25 has an extension dimension of the separator end portion 5d extending from the winding end 25a of the other negative electrode sheet 25 of 15 mm or more. Is set to

  The nonwoven fabric 28 of the separator 5 is made of polyolefin such as polyethylene (PE) or polypropylene (PP), polyester such as polyethylene terephthalate (PET) or polybutylene terephthalate (PBT), or thermoplastic resin such as polyphenylene sulfide (PPS). It is formed by a known manufacturing method. The nonwoven fabric 28 has a thickness dimension of 40 μm and a vertical width dimension of 40 mm. The microporous film 29 of the separator 5 is made of polyolefin such as polyethylene or polypropylene, polyester such as polyethylene terephthalate or polybutylene terephthalate, or thermoplastic resin such as polyphenylene sulfide.

  The microporous film 29 of the separator 5 is formed by, for example, blending fine fine particles (inorganic fine particles) with the resin, forming into a film-like body, and extending the film in a uniaxial direction or biaxial direction to crack in the vicinity of the fine particles. Micropores are formed by generating. The pore diameter of the microporous film 29 is about 0.05 μm. That is, the pore diameter of the microporous film 29 is smaller than the diameter of the lithium-aluminum alloy fine powder formed on the negative electrode sheets 24 and 25.

  The microporous film 29 has a thickness dimension of 30 μm and a vertical width dimension that is 50 mm larger than that of the nonwoven fabric 28. And as shown in FIG. 7, the separator 5 is comprised so that each upper and lower end part of the microporous film 29 may be located in the outer side of the up-down direction rather than each upper and lower end part of the nonwoven fabric 28, respectively. Note that the horizontal direction in FIG. 7 is the vertical direction of the separator 5. The melting point of the nonwoven fabric 28 is about 140 ° C., and the melting point of the microporous film 29 is about 130 ° C. lower than the melting point of the nonwoven fabric 28.

  In the wound state in which the positive electrode 3 and the negative electrode 4 are wound through the separator 5, the upper end portion 29a and the lower end portion 29b of the microporous film 29 of the separator 5 are respectively a pair of upper and lower hot plates 31 and 32 (FIG. 8). It is heated and pressed from above and below. As a result, the upper and lower ends 29a and 29b of the microporous film 29 of the separator 5 are deformed so that the electrode winding body 6 protrudes from the upper and lower ends of the positive and negative electrodes 3 and 4 as shown in FIG. The cover part 30 of the separator 5 bent along the upper and lower end surfaces of the wound body 6 is formed. The upper and lower ends of the positive and negative electrodes 3 and 4 are covered by the cover portion 30. Thereby, the electrode winding body 6 of the present invention is completed. In addition, the cover part 30 of the separator 5 does not need to completely block the upper and lower sides of the positive and negative electrodes 3 and 4, and may have a gap that allows the electrolytic solution and the positive electrode lead body 15 to pass therethrough.

  The hot plates 31 and 32 heat the microporous film 29 of the separator 5 at 125 ° C., for example. The deformation of the upper and lower end portions 29a and 29b of the microporous film 29 includes melting at least a part by the heating. That is, the upper end 29a on the inner peripheral side and the outer peripheral side of the winding of the microporous film 29 is thermally welded by the melting, and the lower end portion 29b on the inner peripheral side and the outer peripheral side of the winding is thermally welded. Thus, forming the cover portion 30 is also included. Further, the cover portion 30 may be formed by simply bending and deforming the upper end portion 29a and the lower end portion 29b of the microporous film 29 of the separator 5 without heating.

As an electrolytic solution, a chain ether such as DME or dimethyl carbonate in a cyclic carbonate such as PC or EC is dissolved in a solvent in which a solute such as LiPF ₆ , LiClO ₄ or LiCF ₃ SO _{3 is} dissolved in an amount of 0.3 to 1.5 M / l. An electrolytic solution in which a chain carbonate such as nate is mixed is used.

  The electrode winding body 6 can be produced, for example, according to the procedure shown in FIGS. First, as shown in FIG. 5, the separator 5 is placed on the upper surface of the negative electrode current collector 26 in the length direction via a heat-meltable tape 34, and the tape 34 is heated to remove the separator 5 from the negative electrode. It adheres to the upper surface of the current collector 26. Further, in the negative electrode current collector 26, the negative electrode sheet 24 and the negative electrode sheet 25 in which the aluminum foil 27 is fixed in a laminated state in both of the length direction of the negative electrode current collector 26 with the fixing portion of the separator 5 interposed therebetween. Is placed.

  Next, as shown in FIG. 6 (a), the fixed portion of the separator 5 is sandwiched between two cores 36, and the core 36 is rotated about a half circumference as shown in FIG. The body 26 and the separator 5 are wound around the core 36. Next, as shown in FIG. 7, the positive electrode 3 is placed on the negative electrode 4 through the separator 5 and wound around the winding core 36. In this state, the positive electrode 3 is wound together with the negative electrode 4 and the separator 5. After the winding is completed, the positive and negative electrodes 3 and 4 and the separator 5 are extracted from the winding core 36. A positive electrode lead body 15 is connected to a portion of the positive electrode 3 near the outermost periphery of the positive electrode current collector 22.

  As shown in FIGS. 8A and 8B, the pair of upper and lower hot plates 31 and 32 described above are pressed against the upper and lower ends of the microporous film 29 of the rolled separator 5 and heated. Thus, the cover portion 30 is formed and the upper and lower ends of the positive and negative electrodes 3 and 4 are covered. Thus, the electrode winding body 6 shown in FIG. 1 can be obtained. The upper hot plate 31 has a hole 37 through which the positive electrode lead body 15 passes. Then, the position of the positive electrode lead body 15 is detected by a sensor (not shown), the upper hot plate 31 is driven so that the positive electrode lead body 15 is positioned in the hole 37, and then hot is applied to the upper and lower ends of the microporous film 29. The plates 31 and 32 are pressed. This prevents the positive lead body 15 from being pressed against the separator 5 by the upper hot plate 31 and being crushed.

  Next, the electrode winding body 6 is accommodated in the outer can 2. Here, the electrode winding body 6 is press-fitted into the outer can 2. That is, the electrode winding body 6 is produced so as to have the same or slightly smaller outer diameter size as the inner diameter dimension of the outer can 2, and a pressing action derived from the diameter expansion deformation force of the electrode winding body 6. Thus, the outermost peripheral surface of the negative electrode current collector portion 26b on the other side of the negative electrode current collector 26 of the electrode winding body 6 is in close contact with the inner surface of the outer can 2 in a pressed state. Finally, after the electrolytic solution is charged, the lid 8 is fixed to the inner periphery of the upper opening of the outer can 2, whereby the nonaqueous electrolyte battery 1 shown in FIGS. 1 and 4 can be obtained.

  As described above, since the upper and lower ends of the positive and negative electrodes 3 and 4 are covered by the cover portion 30 of the separator 5, there is a risk that the negative electrode active material and the like that have fallen off from the negative electrode 4 may wrap around the upper and lower ends of the separator 5 In addition, there is no possibility that the positive electrode active material dropped from the positive electrode 3 wraps around the upper and lower ends of the separator 5 and reaches the negative electrode 4. Thereby, the fallen negative electrode active material can be prevented from reacting with the positive electrode active material of the positive electrode 3, and the fallen positive electrode active material can be prevented from reacting with the negative electrode active material of the negative electrode 4.

  The negative electrode active material dropped from the negative electrode 4 wraps around the end portions 5c and 5d of the separator 5 to reach the positive electrode 3, or the positive electrode active material dropped from the positive electrode 3 wraps around the end portions 5c and 5d of the separator 5 In order to reduce reaching 4, the elongation of the separator end portions 5c and 5d is preferably long. However, if the separator 5 is excessively long, the battery capacity is greatly reduced due to the arrangement of the separator 5, so that the extension amount of the separator end portions 5c and 5d is preferably 19 mm or less.

It is a vertical side view of the non-aqueous electrolyte battery according to the present invention. 1 is a cross-sectional plan view of a nonaqueous electrolyte battery according to the present invention. FIG. 3 is an enlarged view of a portion A in FIG. 2. It is a vertical side view which shows the whole nonaqueous electrolyte battery. It is a figure for demonstrating the preparation methods of the electrode winding body which concerns on this invention. (A) * (b) is a figure for demonstrating the preparation methods of an electrode winding body. It is the BB sectional view taken on the line of FIG.6 (b). (A) * (b) is a figure for demonstrating the preparation methods of an electrode winding body.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Nonaqueous electrolyte battery 2 Outer can 3 Positive electrode 4 Negative electrode 5 Separator 6 Electrode winding body 28 Non-woven fabric 29 Microporous film 29a Microporous film upper end part 29b Microporous film lower end part 30 Cover part

Claims (4)

A cylindrical non-water containing an electrode winding body in which a sheet-like positive electrode and a sheet-like negative electrode are wound through a sheet-like separator in a bottomed cylindrical outer can having an upper opening. An electrolyte battery,
The electrode winding body has upper and lower ends of the positive and negative electrodes of the electrode winding body by cover portions that are deformed at both the upper and lower ends of the separator in a wound state and extend along the upper and lower end surfaces of the electrode winding body. Covered ,
The separator is configured by stacking a nonwoven fabric and a microporous film,
The microporous film has a vertical width dimension that is larger than a vertical width dimension of the nonwoven fabric, and the cover portion is formed by upper and lower end portions of the microporous film. Electrolyte battery. The microporous film of the separator is made of a thermoplastic resin,
The nonaqueous electrolyte battery according to claim 1, wherein the cover portion is formed by heating and deforming both upper and lower end portions of the wound microporous film . The melting point of the microporous film, non-aqueous electrolyte battery according to claim 2, wherein that is lower than the melting point of the nonwoven fabric. Wherein by upper and lower end portions to each other of the inner periphery side and the outer periphery side of the winding in the microporous film is thermally welded, the non-aqueous electrolyte battery according to claim 2 or 3, wherein said cover portion is Ru is formed.

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