JP5518763B2 - Non-aqueous electrolyte battery - Google Patents

Description

  The present invention relates to a non-aqueous electrolyte battery.

  In a lithium ion battery, a cleavage valve is provided in order to prevent the single battery (cell) from being ignited or ruptured under abnormal heating conditions due to overcharge or short circuit. However, under abnormal heating conditions, there may be a problem that the winding group and the battery can are deformed due to an increase in internal pressure caused by a chemical reaction in the battery can and the gas release path is blocked.

  Patent Document 1 discloses a battery in which an electrode pressing plate made of a thermosetting resin is disposed for the purpose of ensuring safety by allowing gas to easily dissipate out of the battery via a safety valve. Yes.

  Patent Document 2 discloses a lead member that plastically processes a metal plate and connects a current collector plate and an electrode terminal mechanism in order to prevent the gas discharge function of the gas discharge valve from being hindered. A rectangular battery having a gas discharge valve attached at a position facing the surface is disclosed.

JP-A-6-163079 JP 2005-267945 A

  A battery used as a power source for an electric vehicle or the like must have both output and safety. The wound lithium ion secondary battery has a structure in which electrode foil end portions are bundled and welded. However, particularly in a flat wound type lithium ion secondary battery, gas generated between the electrodes inside the wound electrode group accumulates, and the flat part of the wound electrode group deforms and breaks down. However, there is a risk that it will be ejected outside the wound electrode group.

  An object of the present invention is to provide a safe non-aqueous electrolyte secondary battery having a structure in which a cleavage valve operates normally under an abnormal condition to prevent gas accumulation and has excellent gas release characteristics at the time of abnormality. There is.

  A non-aqueous electrolyte battery according to the present invention includes a flat wound electrode winding group having a positive electrode lead and a negative electrode lead, and a positive electrode current collecting plate and a negative electrode current collecting plate electrically connected to the electrode winding group And a battery can containing the electrode winding group, the positive electrode current collector plate and the negative electrode current collector plate, wherein the positive electrode current collector plate has a positive electrode welded portion and a positive electrode opening portion where the positive electrode lead is welded. The negative electrode current collector plate has a negative electrode welded portion and a negative electrode opening welded to the negative electrode lead, and the negative electrode current collector plate is closed on the negative electrode current collector plate side by the negative electrode welded portion. It is a positive electrode side gas discharge path for releasing gas generated in the region of the electrode winding group to the outside of the battery can, and the negative electrode opening portion is closed on the positive electrode current collector plate side by the positive electrode welding portion. A negative gas that releases the gas generated in the area of the electrode winding group to the outside of the battery can. Characterized in that a side gas discharge path.

  According to the present invention, a gas discharge path can be secured without being affected by deformation of a flat or rectangular battery can, and the safety of the battery during abnormal heat generation can be improved.

FIG. 3 is a partial development view illustrating a configuration of a wound group according to the first embodiment. 3 is a top view showing a wound group of Example 1. FIG. It is a side view which shows the winding group of Example 1. FIG. It is a perspective view which shows the joining process of the winding group of Example 1, and a positive electrode current collecting plate. It is a perspective view which shows the joining process of the winding group of Example 1, and a positive electrode current collecting plate. It is a disassembled perspective view which shows the structure of a battery. It is sectional drawing which shows the structure of a battery. It is sectional drawing which shows the structure of a battery. It is a perspective view which shows the battery after an assembly. 1 is a cross-sectional view showing a battery of Example 1. FIG. 3 is a front view showing a positive electrode current collector plate of a battery of Example 1. FIG. 3 is a front view showing a negative electrode current collector plate of the battery of Example 1. FIG. It is sectional drawing which shows the flat type battery can in a normal state. It is sectional drawing which shows the expanded flat battery can. It is a front view which shows the gas discharge path | route from the expanded flat battery can. FIG. 10 is a front view showing a gas discharge path opposite to the gas discharge path of FIG. 9. 10 is a top view showing a wound group of Example 2. FIG. 6 is a side view showing a wound group of Example 2. FIG. It is a perspective view which shows the joining process of the winding group of Example 2, and a positive electrode current collecting plate. It is a perspective view which shows the joining process of the winding group of Example 2, and a positive electrode current collecting plate. 6 is a schematic cross-sectional view illustrating a bonding process of a wound group and a positive electrode current collector plate in Example 2. FIG.

  The present invention relates to a high-power, large-capacity non-aqueous electrolyte battery used for in-vehicle applications and the like, and more particularly to a non-aqueous electrolyte battery applicable to a flat or rectangular flat wound lithium ion battery.

  The non-aqueous electrolyte battery of the present invention is a secondary battery having a cleavage valve on both side end faces of a battery can and having a flat wound type electrode winding group therein, one end face of the electrode winding group The positive electrode foil is bundled and welded, and the negative electrode foil is bundled and welded at the other one side end face, and one welded portion is provided on one side with respect to the plane that is the winding center of the electrode winding group. The welded portion of the other current collector plate is disposed on the opposite side to the winding center plane. Thereby, the discharge path of the gas generated inside the electrode winding group is secured.

  In the nonaqueous electrolyte battery of the present invention, there is no need to dispose a battery can or a part that suppresses deformation of the wound group in the battery can. In addition, the nonaqueous electrolyte battery of the present invention is suitable for large-current charge / discharge, and has excellent gas release characteristics at the time of abnormality and is safe.

  Hereinafter, a nonaqueous electrolyte battery according to an embodiment of the present invention will be described.

  The non-aqueous electrolyte battery includes a flat wound type electrode winding group having a positive electrode lead and a negative electrode lead, and a positive electrode current collecting plate and a negative electrode current collecting plate electrically connected to the electrode winding group, A secondary battery having a cleavage valve on both end face portions of the battery can that intersects the winding axis of the electrode winding group. . The positive electrode current collector plate and the negative electrode current collector plate are arranged at positions intersecting the winding axis, and the positive electrode current collector plate has a positive electrode welded portion where a positive electrode lead is welded and a positive electrode opening, and the negative electrode current collector plate Has a negative electrode welded portion welded with a negative electrode lead and a negative electrode opening. The positive electrode opening is a positive electrode that releases the gas generated in the area of the electrode winding group in which the negative electrode current collector plate side is closed by the negative electrode welded part to the outside of the battery can through the cleavage valve on the positive electrode current collector plate side. The negative electrode opening is a side gas discharge path, and the gas generated in the region of the electrode winding group in which the positive electrode current collector plate side is closed by the positive electrode welded portion is connected to the battery via the cleavage valve on the negative electrode current collector plate side. This is a negative-side gas discharge path that discharges to the outside of the can.

  In the non-aqueous electrolyte battery, a positive electrode welded portion and a negative electrode opening are provided in one region obtained by dividing the battery can into two parts on a plane parallel to the flat surface of the battery can, and the battery can is divided into two parts on the surface. In the other region, a negative electrode weld and a positive electrode opening are provided.

  In the non-aqueous electrolyte battery, the positive electrode welded portion is provided on the flat plate portion provided with the positive electrode opening portion of the positive electrode current collector plate, and the negative electrode weld portion is provided on the flat plate portion provided with the negative electrode opening portion of the negative electrode current collector plate. It is provided.

  In the non-aqueous electrolyte battery, the positive electrode welded portion is provided on a joining plate joined to a flat plate portion provided with a positive electrode opening portion of the positive electrode current collector plate, and the negative electrode welded portion is a negative electrode opening portion of the negative electrode current collector plate. It is provided in the joining board joined to the flat plate part which provided.

  In the non-aqueous electrolyte battery, the positive electrode lead and the negative electrode lead are a plurality of lead pieces provided at both ends in the winding axis direction of the electrode winding group.

  In the non-aqueous electrolyte battery, the positive electrode lead is a positive electrode uncoated portion provided at one end in the winding axis direction of the electrode winding group, and the negative electrode lead is a winding axis of the electrode winding group. This is a negative electrode uncoated portion provided at the other end in the direction.

  Embodiments will be described below with reference to the drawings.

  FIG. 1 is a partial development view showing a configuration example of a wound group applied to a nonaqueous electrolyte battery.

  In this figure, the winding group 102 (electrode winding group) includes a strip-like positive electrode 401 in which a positive electrode mixture is applied to both surfaces of an aluminum foil base material, and a strip-like positive electrode mixture in which a negative electrode mixture is applied to both surfaces of a copper foil base material. The negative electrode 402 is overlapped with two separators 403 and wound around a plate-like core 404.

  At one end in the width direction of the positive electrode 401, the positive electrode mixture is not applied and the aluminum foil base material is exposed. Further, a strip-like positive electrode tab 405 (positive electrode lead piece) is formed at the one end. A plurality are formed. On the other hand, the copper foil base material is exposed without applying the negative electrode mixture at one end portion in the width direction of the negative electrode 402, and a strip-shaped negative electrode tab 406 (negative electrode lead piece) is formed at the end portion. Has been. The positive electrode tab 405 and the negative electrode tab 406 are formed on opposite sides. Each of the positive electrode tab 405 and the negative electrode tab 406 preferably has a width of 2 mm to 10 mm and a length of 15 mm to 50 mm.

  2A and 2B show the configuration of the wound group 102. FIG. FIG. 2A is a top view and FIG. 2B is a side view.

  In these drawings, a positive electrode tab 405 (positive electrode lead piece) protrudes from one end portion (left side in the drawing) of the winding group 102, and the other end portion (right side in the drawing) of the winding group 102. ) Protrudes from the negative electrode tab 406 (negative electrode lead piece). As shown in FIG. 2A, the width A of the positive electrode tab 405 and the negative electrode tab 406 protruding from both ends of the wound group 102 is preferably smaller than the width B of the core 404. On the other hand, as shown in FIG. 2B, the positive electrode tab 405 and the negative electrode tab 406 are disposed on opposite sides of the winding core 404 that is the winding center plane of the winding group 102 (that is, the positive electrode tab 405). And the negative electrode tab 406 are arranged in parallel to the flat surface of the wound group 102 and opposite to each other across a surface that bisects the wound group 102).

  3A and 3B show a method of joining the wound group 102 and the positive electrode current collector plate 104. In addition, since the same process is used also on the negative electrode side, description is omitted here.

  The outer shape of the flat plate portion of the positive electrode current collector plate 104 facing the end portion of the wound group 102 is smaller than the outer shape of the oval end surface portion of the wound group 102 and larger than the outer shape of the end surface portion of the winding core 404. It is a substantially oval plate having a thickness of 0.5 to 5 mm. A positive electrode terminal 109 is fixed to the end of the positive electrode current collector plate 104 by welding or the like.

  First, as shown in FIG. 3A, the positive electrode current collector plate 104 is arranged in parallel with the flat portion of the wound group 102, and a bundle of positive electrode tabs 405 (positive electrode lead pieces) is arranged on the back surface of the positive electrode current collector plate 104. It is pressed against the joint 601 and welded in close contact. Here, the tab joint portion 601 on the positive electrode side after welding is referred to as a positive electrode weld portion. Similarly, the tab joint on the negative electrode side after welding is referred to as a negative electrode weld.

  Next, as shown in FIG. 3B, the positive electrode current collector plate 104 is disposed perpendicular to the flat portion of the wound group 102, and is disposed at both ends of the opening 602 (positive electrode opening) of the positive electrode current collector plate 104. The positive current collector plate 104 is fixed to the core 404 by fitting the current collector plate protrusion 603 into the groove 407 of the core 404.

  As described above, the positive electrode tab 405 is bundled and welded to one end face of the wound group 102. On the negative electrode side, similarly to the positive electrode side, the negative electrode tab (negative electrode lead) is bundled and welded to the negative electrode current collector plate. The welding portion of one current collector plate is provided at the end of the electrode winding group on one side (front side) when the electrode winding group is divided into the front side and the back side of the core 404, and the other current collecting plate is provided. The welded portion of the electric plate is disposed at the end of the electrode winding group on the reverse side (back side).

  In this figure, for the purpose of explanation, the positive electrode tab 405 is drawn longer than necessary. However, the positive electrode tab 405 may be shorter than shown in the drawing as long as there is room for fitting the current collector plate projection 603 into the groove 407. .

  Next, an example of the assembly process of the nonaqueous electrolyte battery will be described.

  FIG. 4 is an exploded perspective view showing the configuration of the battery.

  First, a rectangular, oval or rectangular battery can 101 having a flat cross-sectional shape is manufactured. Further, the positive electrode terminal 109 and the negative electrode terminal 110 are connected to the positive electrode current collector plate 104 and the negative electrode current collector plate 105, respectively, by welding or the like. The positive electrode current collector plate 104 and the negative electrode current collector plate 105 are provided with openings 602 (positive electrode openings and negative electrode openings), which serve as an exhaust path when the internal pressure of the cell increases. A positive electrode tab 405 and a negative electrode tab 406 are welded to the positive electrode current collector plate 104 and the negative electrode current collector plate 105, respectively. Then, the current collector plate convex portion 603 is fitted into the groove 407 of the winding core 404 wound around the winding group 102.

  Next, the insulating cover 111 produced by resin molding is placed on the positive electrode current collector plate 104 and the negative electrode current collector plate 105, and the wound group 102, the positive electrode current collector plate 104, the negative electrode current collector plate 105, and the insulating cover 111 are integrated. The resulting product is inserted into the battery can 101. The insulating cover 111 includes an electrode opening 303 and a gas discharge opening 302.

  A gasket 112 (made of resin) for the positive electrode terminal 109 is attached inside the positive electrode side sealing plate 116, and the positive electrode side sealing plate 116 is welded to the end of the battery can 101. Similarly, the gasket 112 (made of resin) of the negative electrode terminal 110 is attached to the inside of the negative electrode side sealing plate 103, and the negative electrode side sealing plate 103 is welded to the end of the battery can 101. Welding is performed by an electron beam or a laser. Each of the positive electrode side sealing plate 116 and the negative electrode side sealing plate 103 includes an electrode terminal opening 304, and a central portion thereof includes a cleavage valve 108. The positive electrode side sealing plate 116 also includes a liquid injection hole 301 for injecting an electrolytic solution.

  Next, the gasket 115 is attached to the outside of the positive electrode side sealing plate 116 and the negative electrode side sealing plate 103 and fixed by the nut 113.

  Finally, an electrolytic solution is injected from the liquid injection hole 301 of the positive electrode side sealing plate 116 in a low humidity environment and sealed with the liquid injection plug 107, and the assembly of the battery is completed.

  5A and 5B are cross-sectional views showing examples of the nonaqueous electrolyte battery of this example. 5A shows a cross section parallel to the flat surface of the battery, and FIG. 5B shows a cross section perpendicular to the flat surface of the battery.

  In these figures, a nonaqueous electrolyte battery 100 includes a wound group 102 together with an electrolyte in a rectangular, oval or rectangular battery can 101 having a flat cross-sectional shape, and includes a positive electrode side sealing plate 116 and a negative electrode. Both end portions are sealed with a side sealing plate 103. The battery can 101, the positive electrode side sealing plate 116, and the negative electrode side sealing plate 103 are made of aluminum or stainless steel. The positive electrode side sealing plate 116 is provided with a positive electrode terminal 109 made of aluminum, and the negative electrode side sealing plate 103 is provided with a negative electrode terminal 110 made of copper. The positive electrode terminal 109 and the negative electrode terminal 110 are connected to the positive electrode current collector plate 104 made of aluminum and the negative electrode current collector plate 105 made of copper, respectively, by welding or the like.

  The positive electrode current collector plate 104 and the negative electrode current collector plate 105 are fitted to a cylindrical or plate-like core 404 to which the wound group 102 is wound. The core 404 is manufactured by resin shaping, and if it is a thermoplastic resin, polypropylene or polyphenylene sulfide is used, and if it is a thermosetting resin, a phenol resin, a melamine resin, an unsaturated polyester, or the like is used, If it has electrical insulation and heat resistance, it will not specifically limit.

  A cleavage valve 108 is provided at the center of the negative electrode side sealing plate 103. The positive side sealing plate 116 is provided with a liquid injection stopper 107 in addition to the cleavage valve 108.

  An insulating cover 111 is disposed between the positive electrode side sealing plate 116 and the positive electrode current collector plate 104 and between the negative electrode side sealing plate 103 and the negative electrode current collector plate 105 so as to cover the current collector plate. Yes. The insulating cover 111 has openings at positions corresponding to the positive terminal 109, the negative terminal 110, and the cleavage valve 108.

  A resin gasket 112 is provided inside the positive electrode terminal 109 and the negative electrode terminal 110 (inside the battery can 101), and a gasket 115 is provided outside the positive electrode terminal 109 and the negative electrode terminal 110 (outside the battery can 101). Is provided. These gaskets 112 and 115 are fixed from the outside of the positive side sealing plate 116 and the negative side sealing plate 103 by nuts 113. The insulating cover 111 and the two types of gaskets 112 and 115 are preferably produced by resin molding. If a thermoplastic resin, polypropylene or polyphenylene sulfide is used, and if a thermosetting resin, a phenol resin, Melamine resins, unsaturated polyesters, and the like are used, but they are not particularly limited as long as they have electrical insulation and heat resistance.

  The positive electrode tab 405 and the negative electrode tab 406 are formed in groups, and protrude from both ends of the flat wound group 102, respectively. The positive electrode tab 405 and the negative electrode tab 406 are bundled and welded to the positive electrode current collector plate 104 and the negative electrode current collector plate 105, respectively.

  As shown in FIG. 5B, the positive electrode tab 405 and the negative electrode tab 406 are provided on the flat portion of the winding group 102 that is opposite to the winding core of the winding group 102 (core 404 in FIG. 4). And it is welded so that it may be arrange | positioned on the reverse side (opposite side) with respect to a core. As a result, the positive electrode tab 405 and the negative electrode tab 406 respectively block half of the positive electrode current collector plate 104 side and the negative electrode current collector plate 105 side of the wound group 102. In addition, gas discharge paths 114 (positive gas discharge path and negative gas discharge path) are provided on both sides of the core, and the battery can 101 is deformed when gas is generated in the battery due to battery abnormality. Even in this case, the gas discharge path 114 can be secured.

  FIG. 6 is a perspective view showing the external shape of the assembled battery.

  The positive electrode side sealing plate 116 welded to the battery can 101 has a structure in which a positive electrode terminal 109 protruding from the positive electrode side sealing plate 116 is fixed with a nut 113 while having a liquid injection stopper 107 and a cleavage valve 108.

  Hereinafter, the structure of the positive electrode current collector plate and the negative electrode current collector plate will be described with reference to FIGS.

  FIG. 7A shows a cross section orthogonal to the flat portion of the core, and FIGS. 7B and 7C show the front surfaces of the positive electrode current collector plate and the negative electrode current collector plate, respectively.

  The positive electrode current collector plate 104 has a substantially oval shape, the outer shape of the flat plate portion is smaller than the outer shape of the oval end surface portion of the wound group 102, larger than the outer shape of the end surface portion of the winding core 404, and has a thickness of 0. It is a 5-5 mm board, and is arrange | positioned with respect to the winding axis | shaft of the winding group 102 at right angles.

  A positive electrode terminal 109 is welded to the end of the positive electrode current collector plate 104. Further, the positive electrode current collector plate 104 has two current collector plate convex portions 603 on the surface facing the wound group 102 (inside the battery can 101), and is fitted to the core 404. The positive electrode tab 405 is welded to a tab joint portion 601 provided in one region of the surface of the positive electrode current collector plate 104 facing the wound group 102 that is divided into two by the major axis of the positive electrode current collector plate 104. An opening 602 is provided in the other region of the positive electrode current collector plate 104 that is divided into two along the long axis. The opening 602 has an opening area of 30% to 200% with respect to the battery cleavage valve (the cleavage valve 108 in FIG. 4).

  On the other hand, the negative electrode current collector plate 105 is also generally oval, the outer shape of the flat plate portion is smaller than the outer shape of the oval end surface portion of the wound group 102, larger than the outer shape of the end surface portion of the winding core 404, and has a thickness of The plate is 0.5 to 5 mm, and is arranged perpendicular to the winding axis of the winding group 102.

  A negative electrode terminal 110 is welded to the end of the negative electrode current collector plate 105. The negative electrode current collector plate 105 has two current collector plate protrusions 603 on the surface facing the winding group 102 and is fitted to the core 404. The negative electrode tab 406 is welded to a tab joint portion 601 provided in one area of the surface of the negative electrode current collector plate 105 facing the wound group 102 that is divided into two by the major axis of the negative electrode current collector plate 105. An opening 602 is provided in the other region of the negative electrode current collector plate 104 that is divided into two along the long axis. The opening 602 has an opening area of 30% to 200% with respect to the battery cleavage valve 108 (the cleavage valve 108 in FIG. 4).

  As shown in FIGS. 7B and 7C, each opening 602 in the positive electrode current collector plate 104 and the negative electrode current collector plate 105 has a winding group in a plane parallel to the flat surface of the winding group 102 (or the battery can 101). 102 (or battery can 101) is provided in each of the two regions. That is, the region where the opening 602 is provided in the positive current collector 104 is different from the region where the opening 602 is provided in the negative current collector 105. The region where the tab junction 601 is provided in the positive current collector 104 is also different from the region where the tab junction 601 is provided in the negative current collector 105. Note that the opening 602 may protrude from one of the above-described regions as long as the gas generated in the region can be discharged.

  8A and 8B show the state of the central portion of the battery can before and after the pressure rises isotropically inside the flat battery in the abnormally heated state. FIG. 8A shows a state before the battery can 101 expands, and FIG. 8B shows a state where the battery can 101 expands in an abnormal heating state.

  Due to the structure of the battery of this embodiment, when isotropic internal pressure is applied, a force that causes the battery can 101 to expand in a direction perpendicular to the flat surface of the battery can 101 works, and in a direction parallel to the flat surface of the battery can 101. Acts to compress the battery can 101. If the buckling strength of the winding core 404 is sufficiently high, the gas generated from the battery can in an abnormally heated state is concentrated in the region I or II in the figure no matter where the source is inside the battery. It will be.

  FIG. 9 shows an example of the gas discharge path 114 on the positive electrode side when an abnormal heating state is caused by a minute short circuit.

  In a direction perpendicular to the flat surface of the battery can 101, a micro short circuit occurs in one region (a region below the core 404 in the figure) obtained by dividing the battery can 101 in a plane parallel to the flat surface of the battery can 101. In this case, the gas generated in that region passes through the opening 602 of the positive electrode current collector plate 104, passes through the gas discharge opening 302 of the insulating cover 111, and is provided outside the gas discharge opening 302. It is efficiently discharged from the cleavage valve (cleavage valve 108 in FIG. 4).

  FIG. 10 shows a gas discharge path on the negative electrode side located on the opposite side of the gas discharge path on the positive electrode side shown in FIG.

  In a direction perpendicular to the flat surface of the battery can 101, a micro short-circuit occurs in one region (the region above the core 404 in the figure) obtained by dividing the battery can 101 in a plane parallel to the flat surface of the battery can 101. In this case, the gas generated in that region passes through the opening 602 of the negative electrode current collector plate 105, passes through the gas discharge opening 302 of the insulating cover 111, and is provided outside the gas discharge opening 302. It is efficiently discharged from the cleavage valve (cleavage valve 108 in FIG. 4).

  As described above, according to the present embodiment, the gas discharge path can be arranged on both sides of the winding core 404 of the wound group, and the gas can be discharged efficiently even when the battery can is deformed.

  In the present embodiment, the positive electrode lead and the negative electrode lead are formed using a plurality of lead pieces (tabs), but is not limited thereto, and is parallel to the flat surface of the wound group, and An undivided (series) lead piece may be used.

  Another current collecting structure of the nonaqueous electrolyte battery will be described. In addition, since it is the same as that of Example 1 except the current collection structure, description is abbreviate | omitted here.

  11A and 11B show a top view and a side view of the wound group 102. FIG.

  In these drawings, one end of the wound group 102 is provided with a positive electrode uncoated portion 1101 (positive electrode uncoated portion) that is not coated with the positive electrode mixture, and the other end. Is provided with a negative electrode uncoated portion 1102 (a negative electrode uncoated portion) which is not coated with a negative electrode mixture.

  In the present embodiment, unlike the first embodiment, a plurality of divided positive electrode tabs and negative electrode tabs are not provided.

  12A and 12B show a joining process between the wound group 102 and the positive electrode current collector plate 1103. FIG. 12A shows a state before bonding, and FIG. 12B shows a state after bonding. Since the same process is used on the negative electrode side, the description is omitted here.

  In FIG. 12A, a positive electrode current collector plate 1103 is a substantially oval plate made of aluminum having a thickness of 0.5 to 5 mm (a flat plate portion of the positive electrode current collector plate), and is rectangular in a direction perpendicular to the plate. A plate 1201 (indicated by a dotted line in the figure, also referred to as a joining plate) is provided, and two protrusions 1104 are provided at the end of the rectangular plate 1201. The protrusion 1104 is for fitting with a groove 407 provided in the core.

  Also in the present embodiment, as in the first embodiment, the positive electrode terminal 109 is fixed to the end portion of the positive electrode current collector plate 1103 by welding or the like, and an opening 602 for gas discharge is provided.

  First, the positive electrode current collector plate 1103 is disposed in parallel to the end face (end portion) of the wound group 102 and fixed by fitting into the groove 407 of the core. Next, the positive electrode uncoated portion 1101 is pressed and welded to the tab joint portion 601 on one side of the rectangular plate 1201 protruding from the positive electrode current collector plate 1103.

  Similarly, on the negative electrode side, the negative electrode uncoated portion is pressed and welded to the tab joint portion of the negative electrode current collector plate located on the back side of the positive electrode side tab joint portion 601 located on the front side of the core.

  FIG. 12C is a cross-sectional view illustrating a joining process between the wound group and the current collector plate.

  This figure shows a state after the positive electrode uncoated portion 1101 is welded to the tab joint portion 601 and before the negative electrode uncoated portion 1102 is welded to the negative electrode current collector plate 1105.

  In welding on the negative electrode side, a jig 1501 is inserted from the opening 602 of the negative electrode current collector plate 1105, and the jig 1501 is used to make a perpendicular to the negative electrode current collector plate 1105 (the flat plate portion of the negative electrode current collector plate). The rectangular plate 1201 arranged in the direction is supported and welded from the direction of the arrow 1502. Thereby, the negative electrode non-coating part 1102 can be welded to the opposite side of the welding part on the positive electrode side.

  As described above, in this embodiment, the positive electrode uncoated portion 1101 is bundled and welded to one side of the flat surface of the wound group 102 and the negative electrode uncoated portion 1102 is bundled to the other side of the flat surface. Can be welded. As a result, a part of the positive electrode uncoated part 1101 becomes a positive electrode lead, and a part of the negative electrode uncoated part 1102 becomes a negative electrode lead.

  According to the present embodiment, the gas discharge path can be disposed on both sides of the flat surface of the wound group 102 without forming an electrode tab structure provided with a plurality of tabs, and even when the battery can is deformed, Gas can be discharged efficiently. In addition, productivity can be improved and costs can be reduced.

  In this embodiment, the positive electrode uncoated portion 1101 and the negative electrode uncoated portion 1102 that are not divided are set as the positive electrode lead and the negative electrode lead, respectively. However, the present embodiment is not limited thereto. Also in the example, the positive electrode lead and the negative electrode lead may be formed using a plurality of lead pieces as in the first embodiment.

  100: nonaqueous electrolyte battery, 101: battery can, 102: wound group, 103: negative electrode side sealing plate, 104: positive electrode current collector plate, 105: negative electrode current collector plate, 107: injection plug, 108: cleavage valve , 109: positive electrode terminal, 110: negative electrode terminal, 111: insulating cover, 112: gasket, 113: nut, 114: gas discharge path, 115: gasket, 116: positive electrode side sealing plate, 301: injection hole, 302: gas Emission opening, 303: electrode opening, 304: electrode opening, 401: positive electrode, 402: negative electrode, 403: separator, 404: core, 405: positive electrode tab, 406: negative electrode tab, 407: groove, 601: Tab junction, 602: Opening, 603: Current collector convex part, 1101: Positive electrode uncoated part, 1102: Negative electrode uncoated part, 1103: Positive current collector, 1104: Projection part, 1105: Negative electrode Current collector 1201: plate.

Claims (6)

  A flat wound type electrode winding group having a positive electrode lead and a negative electrode lead, a positive electrode current collecting plate and a negative electrode current collecting plate electrically connected to the electrode winding group, the electrode winding group, and the positive electrode A secondary battery having a cleavage valve on both end surfaces of the battery can intersecting a winding axis of the electrode winding group. The positive electrode current collector plate and the negative electrode current collector plate are disposed at positions intersecting the winding axis, and the positive electrode current collector plate has a positive electrode welded portion and a positive electrode opening portion where the positive electrode lead is welded, and the negative electrode The current collector has a negative electrode welded portion and a negative electrode opening welded to the negative electrode lead, and the positive electrode opening is the electrode winding group in which the negative electrode current collector plate is closed by the negative electrode welded portion. To the outside of the battery can through the cleavage valve on the positive electrode current collector plate side. A positive electrode side gas discharge path to be discharged, and the negative electrode opening portion is configured to supply gas generated in the region of the electrode winding group in which the positive electrode current collector plate side is closed by the positive electrode welded portion of the negative electrode current collector plate. A non-aqueous electrolyte battery, characterized in that it is a negative electrode side gas discharge path that discharges to the outside of the battery can through the cleavage valve on the side.   The positive electrode welded part and the negative electrode opening are provided in one area obtained by dividing the battery can into two parts on a plane parallel to the flat surface of the battery can, and the other part obtained by dividing the battery can into two parts on the surface. The nonaqueous electrolyte battery according to claim 1, wherein the negative electrode welded portion and the positive electrode opening are provided in the region.   The positive electrode welded portion is provided on a flat plate portion provided with the positive electrode opening portion of the positive electrode current collector plate, and the negative electrode weld portion is provided on a flat plate portion provided with the negative electrode opening portion of the negative electrode current collector plate. The nonaqueous electrolyte battery according to claim 2, wherein   The positive electrode welded portion is provided on a joining plate joined to the flat plate portion provided with the positive electrode opening portion of the positive electrode current collector plate, and the negative electrode welded portion is provided with the negative electrode opening portion of the negative electrode current collector plate. The nonaqueous electrolyte battery according to claim 2, wherein the battery is provided on a joining plate joined to the flat plate portion.   The said positive electrode lead and the said negative electrode lead are several lead pieces provided in the both ends of the said winding axis direction of the said electrode winding group, The Claim 1 characterized by the above-mentioned. Non-aqueous electrolyte battery.   The positive electrode lead is a positive electrode uncoated portion provided at one end in the winding axis direction of the electrode winding group, and the negative electrode lead is formed in the winding axis direction of the electrode winding group. The nonaqueous electrolyte battery according to any one of claims 2 to 4, wherein the nonaqueous electrolyte battery is a negative electrode uncoated part provided at the other end.

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