JP2014103101A - Large-capacity lithium ion battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a large-capacity lithium ion battery capable of increasing the strength of a battery can without thickening the thickness of a material forming the battery can.SOLUTION: A lamination type electrode plate group 3 comprising a plurality of laminated electrode plates 31 is stored at the inside of a battery can 5 made of metal. Reinforcing ribs 56 and 57 are integrally formed by press molding in a pair of facing wall parts 51 and 52 located in the lamination direction of the electrode plate group 3 of the battery can 5, respectively. The reinforcing ribs 56 and 57 are formed around bulging sections 58 and 59 which are formed by causing the central portions of the facing wall parts 51 and 52 to bulge toward the electrode plate group 3 side, respectively.

Description

  The present invention relates to a large-capacity lithium ion battery used for a power source that requires a large current, such as a heavy machine.

  Lithium-ion batteries have been widely used mainly for power supplies of small devices such as personal computers and mobile phones, but recently they have been used for electric vehicles, heavy equipment, condominiums and buildings due to their high voltage and high energy density. Considerations are being made to expand the power supply or power storage applications. However, in a large-capacity lithium ion battery intended for such a large device / equipment, the battery can be easily deformed because the surface area of the battery can increases due to the increase in size of the battery. Specifically, the battery can expands or contracts due to temperature change or gas generation in the battery, or the battery may burst in the worst case. Therefore, in the conventional large-capacity lithium ion battery, in order to maintain the strength of the battery can, a structure (Patent Document 1) is adopted in which the thickness of the material forming the battery can is increased.

Japanese Patent No. 4745589, paragraph [0029] and FIG.

  However, when the thickness of the battery can is increased as in a conventional large-capacity lithium ion battery, there is a problem that the weight of the battery can increases and the weight of the entire battery increases.

  An object of the present invention is to provide a large-capacity lithium ion battery that can maintain the strength of the battery without increasing the weight of the battery.

  Another object of the present invention is to provide a large-capacity lithium ion battery that can maintain the strength of the battery without significantly increasing the manufacturing cost.

  The large-capacity lithium ion battery to be improved by the present invention includes a stacked electrode plate group in which a plurality of electrode plates are stacked and a metal battery can, and the electrode plate group is inside the battery can. It is housed and configured. In the large capacity lithium ion battery of the present invention, the battery can is provided with reinforcing ribs. The reinforcing ribs are integrally formed by pressing (press molding), respectively, on a pair of opposing wall portions positioned in the stacking direction of the electrode plate group of the battery can. When the reinforcing rib is provided integrally with the battery can by pressing as described above, it is not necessary to increase the thickness of the material forming the battery can in order to reinforce the battery can. Therefore, even if the battery is enlarged to increase the capacity of the lithium ion battery, the strength of the battery can be maintained without increasing the weight of the battery. In addition, since a part of the facing wall portion of the battery can is configured by the reinforcing rib, it is not necessary to form the reinforcing rib as a separate member from the battery can and attach the reinforcing rib to the battery can by welding or the like. Therefore, the strength of the battery can can be increased without significantly increasing the manufacturing cost of the battery.

  The reinforcing rib is provided with one bulging portion formed by bulging one portion of the opposing wall portion toward the electrode plate group in one pattern, and as a result, is formed around one bulging portion. preferable. Such a bulging portion can be formed by forming a recess in the opposite wall portion of the battery can by press working. And the circumference | surroundings of a recessed part comprise the reinforcing rib as it is. Therefore, by providing such a bulging portion, a reinforcing rib integrated with the battery can can be easily provided. Moreover, since the bulging part formed by bulging a part of a pair of opposing wall part to the electrode plate group side can absorb the expansion | swelling part of a battery (battery can), it makes the volume change of a battery small. be able to.

  In addition, since the center area | region of an opposing wall part is an easily deformable part also in a battery can, it is preferable to determine one place of the opposing wall part which provides one bulging part in the center area | region of an opposing wall part. In such a configuration, since the expansion of the battery can is efficiently absorbed at the portion where the battery can easily deforms, the deformation of the battery can can be prevented even in an environment where the battery can easily expand.

  Further, the shape of the pattern of the bulging portion may be determined such that one reinforcing rib is formed outside one bulging portion and one or more reinforcing ribs are formed inside the bulging portion. . If the pattern shape of the bulging portion is set to such a shape, a plurality of reinforcing ribs can be dispersed and arranged over the entire opposing wall portion, so that the strength of the battery can can be increased.

  The bulging portions provided for forming the reinforcing ribs are not limited to one bulging portion, but two or more formed by bulging two or more locations of the opposing wall portion to the electrode plate group side in two or more patterns. You may comprise as a bulging part. In this case, it is preferable that the shape of the pattern is determined so that two or more patterns form one reinforcing rib continuous around the two or more bulging portions. When two or more pattern shapes are defined in such a shape, the area of one continuous reinforcing rib increases as the number of the bulging portions increases, so that the strength of the battery can can be increased.

  Further, when the reinforcing rib is composed of two or more bulging portions, it is continuous between two bulging portions formed by bulging two portions of the opposing wall portion toward the electrode plate group in two patterns. The shape of the pattern may be determined so that one reinforcing rib is formed and another one bulging portion is formed concentrically outside one bulging portion. In other words, one of the two bulges is formed at the center of the central region of the opposing wall, and one continuous reinforcing rib is formed between the two bulges. Another one bulging part may be formed outside one bulging part. As described above, in the configuration in which one reinforcing rib is provided between the two bulging portions, two bulging portions and one reinforcing rib are provided in the central region of the opposing wall portion that is easily deformed by the expansion of the battery can. Therefore, the strength of the battery can can be reliably increased while efficiently absorbing the expansion of the battery can.

  Reinforcing side wall ribs may be integrally formed by press molding on the pair of side wall portions of the battery can perpendicular to the stacking direction of the electrode plate group and continuous with the pair of opposing wall portions. By providing such side wall ribs on the pair of side wall portions, the strength of the battery can can be further increased without increasing the weight of the battery.

  The side wall ribs can be formed around two or more bulged portions formed by bulging two or more portions of the side wall portion toward the electrode plate group in two or more patterns. In this case, the shape of the two or more patterns may be determined such that one reinforcing side wall rib is formed around the two or more bulging portions. If the shape of the pattern of the bulging part formed in the side wall part is such a shape, not only one continuous reinforcing rib is formed on the pair of opposing wall parts, but also one continuous side wall rib for reinforcing. Is also formed on the pair of side wall portions, the strength of the battery can can be reliably increased.

1 is a partially cutaway perspective view showing a first embodiment of a large-capacity lithium ion battery of the present invention. (A)-(F) are the front view of FIG. 1, a rear view, a top view, a bottom view, a right side view, and a left side view, (G) IIG-IIG of (A) which abbreviate | omitted the internal mechanism. It is line sectional drawing. It is a partially cutaway perspective view showing a second embodiment of a large capacity lithium ion battery of the present invention. FIGS. 3A to 3F are a front view, a rear view, a plan view, a bottom view, a right side view, and a left side view of FIG. 3, and FIG. It is line sectional drawing. It is a partially cutaway perspective view showing a third embodiment of a large capacity lithium ion battery of the present invention. FIGS. 5A to 5F are a front view, a rear view, a plan view, a bottom view, a right side view, and a left side view of FIG. 5, and FIG. 5G is a VIG-VIG of FIG. It is line sectional drawing. It is a figure which shows 4th Embodiment of the high capacity | capacitance lithium ion battery of this invention, (A)-(F) is a front view, a rear view, a top view, a bottom view, a right side view, and a left side view. (G) is a sectional view taken along the line VIIG-VIIG in (A) with the internal mechanism omitted. It is a figure which shows 5th Embodiment of the high capacity | capacitance lithium ion battery of this invention, (A)-(F) is a front view, a rear view, a top view, a bottom view, a right side view, and a left side view. (G) is a cross-sectional view taken along line VIIIG-VIIIG of (A) with the internal mechanism omitted. It is a figure which shows 6th Embodiment of the high capacity | capacitance lithium ion battery of this invention, (A)-(F) is a front view, a rear view, a top view, a bottom view, a right side view, and a left side view. FIG. 6G is a cross-sectional view taken along the line IXG-IXG in FIG. It is a figure which shows 7th Embodiment of the high capacity | capacitance lithium ion battery of this invention, (A)-(F) is a front view, a rear view, a top view, a bottom view, a right side view, and a left side view. FIG. 6G is a cross-sectional view taken along the line XG-XG of FIG. (A)-(F) are the front view of the high capacity | capacitance lithium ion battery of 1st Embodiment, a rear view, a top view, a bottom view, a right view, and a left view, (G) shows an internal mechanism. It is the XIG-XIG sectional view taken on the line (A) omitted. It is a perspective view of the lithium ion battery of 1st Embodiment. (A)-(F) are the front view of the high capacity | capacitance lithium ion battery of 2nd Embodiment, a rear view, a top view, a bottom view, a right view, and a left view, (G) shows an internal mechanism. It is the XIIIG-XIIIG sectional view taken on the line (A) omitted. It is a perspective view of the lithium ion battery of 2nd Embodiment. (A)-(F) are the front view of the large capacity lithium ion battery of 3rd Embodiment, a rear view, a top view, a bottom view, a right view, and a left view, (G) shows an internal mechanism. It is the XVG-XVG sectional view taken on the line (A) which is omitted. It is a perspective view of the high capacity | capacitance lithium ion battery of 3rd Embodiment. (A)-(F) are the front view of the high capacity | capacitance lithium ion battery of 4th Embodiment, a rear view, a top view, a bottom view, a right view, and a left view, (G) shows an internal mechanism. It is the XVIIG-XVIIG sectional view taken on the line (A) omitted. (A)-(F) are the front view of the large capacity | capacitance lithium ion battery of 5th Embodiment, a rear view, a top view, a bottom view, a right view, and a left view, (G) shows an internal mechanism. It is the XVIIIG-XVIIIG sectional view taken on the line (A) omitted. (A)-(F) are the front view of the large capacity lithium ion battery of 6th Embodiment, a rear view, a top view, a bottom view, a right view, and a left view, (G) shows an internal mechanism. It is the XIXG-XIXG sectional view taken on the line (A) omitted. (A)-(F) are the front view of a high capacity | capacitance lithium ion battery of 7th Embodiment, a rear view, a top view, a bottom view, a right view, and a left view, (G) shows an internal mechanism. It is the XXG-XXG sectional view taken on the line (A) omitted.

  Hereinafter, embodiments of the large-capacity lithium ion battery of the present invention will be described in detail. 1 and 2 are views showing a first embodiment of a large-capacity lithium ion battery of the present invention. The large-capacity lithium ion battery 1 of the present embodiment has a square shape with a battery capacity of 210 Ah, dimensions of 152.2 mm in width, 250 mm in height, and 132 mm in depth. In addition, the lithium ion battery of the present invention is not limited to these battery capacities, dimensions, and shapes, and can be appropriately changed depending on the application. For example, it is possible to cope with a case where the depth dimension changes according to the battery capacity. The lithium ion battery 1 includes a laminated electrode plate group 3 and a battery can 5. The electrode plate group 3 has a structure in which several hundred electrode plates 31 are stacked with a separator interposed therebetween. The electrode plate 31 includes a positive electrode plate and a negative electrode plate, and a separator is disposed between the positive electrode plate and the negative electrode plate. The tab provided integrally with the current collector plate of the positive electrode plate is connected to a positive electrode current collector (not shown) provided under the positive electrode terminal 32 and disposed in the battery can 5. A tab provided integrally with the current collector plate of the negative electrode plate is connected to a negative electrode current collector (not shown) provided under the negative electrode terminal 33 and disposed in the battery can 5. The battery can 5 includes a battery can body 50 and a battery lid 7. The battery can body 50 may be manufactured by bending (press-molding) a pressed stainless steel plate with a thickness of 1 mm or more, and welding the butt portion. It may be processed and formed integrally. The battery lid 7 is also formed by pressing a stainless plate.

  The battery can 5 includes a pair of opposing wall portions 51 and 52 and a pair of side wall portions 53 and 54 that are connected to the opposing wall portions 51 and 52 and face each other in a direction substantially orthogonal to the opposing direction of the opposing wall portions 51 and 52. And a bottom wall portion 55 connected to one end of the pair of side wall portions 53 and 54 and constituting the bottom surface of the battery can 5. The battery can body 50 has an opening 50 </ b> A (FIG. 1) on its upper surface, and the electrode plate group 3 is inserted from the opening 50 </ b> A and stored inside the battery can body 50. A plurality of positive electrode tabs included in the electrode plate group 3 are welded to a positive current collector (not shown) connected to the positive electrode terminal 32, and a plurality of negative electrode tabs included in the electrode plate group 3 are The electrode plate group 3 is inserted from the opening 50 </ b> A of the battery can body 50 while being welded to a negative electrode current collector (not shown) connected to the terminal 33. Thereafter, the positive terminal 32 and the negative terminal 33 are inserted into a terminal insertion through hole (not shown) provided in the battery lid 7 via packing, and the battery lid 7 is welded to the edge of the opening 50 </ b> A of the battery can body 50. Thereafter, nuts 34 and 35 are fastened to the positive electrode terminal 32 and the negative electrode terminal 33 protruding from the battery lid 7 through washers. The battery lid 7 is provided with liquid injection ports 9 and 11 and a safety valve 71 including a cleavage valve.

  As shown in FIGS. 1 and 2A, 2B, and 2G, in the large-capacity lithium ion battery of this example, a pair of opposing wall portions positioned in the stacking direction of the electrode plate group 3 of the battery can 5 51 and 52 are provided with reinforcing ribs 56 and 57, respectively. Note that in the cross-sectional view of FIG. 2G, the thickness of a part of the battery can is emphasized for easy understanding. The reinforcing ribs 56 and 57 are integrally formed by forming bulging portions 58 and 59 by pressing on a pair of opposing wall portions 51 and 52 facing and positioned in the stacking direction of the electrode plate group of the battery can 5. Is formed. Specifically, one place (the central region of the opposing wall portion) of each of the pair of opposing wall portions 51 and 52 is pressed (press-molded) in one pattern on the electrode plate group 3 (inside the battery can 5) side. By forming the bulged portions 58 and 59 that are bulged, the periphery of the bulged portions 58 and 59 constitutes the reinforcing ribs 56 and 57. In this example, the reinforcing ribs 56 and 57 are formed so as to surround the outer peripheries of the bulging portions 58 and 59 along the outer edges of the opposing wall portions 51 and 52.

  Thus, when the reinforcing ribs 56 and 57 are integrally formed with the battery can 5 by pressing (when configured as a part of the battery can 5), the thickness of the battery can is increased in order to reinforce the battery can as in the past. There is no need to let them. Therefore, even if the capacity of the lithium ion battery is increased as in this example (even if the battery is enlarged), the strength of the battery can can be maintained without increasing the weight of the battery. Further, part of the opposing wall portions 51, 52 (around the bulging portions 58, 59) of the battery can 5 is composed of the reinforcing ribs 56, 57, so that the reinforcing rib is composed of a separate member from the battery can. Thus, it is not necessary to attach the reinforcing rib to the battery can body 50 by welding or the like. Therefore, the strength of the battery can can be increased without significantly increasing the manufacturing cost of the battery.

  In this example, the shape of the pattern forming the bulging portions 58 and 59 is substantially rectangular. The shape of the reinforcing ribs 56 and 57 is similar to the contour shape (substantially rectangular) of the bulging portions 58 and 59 corresponding to the contour shape of the bulging portions 58 and 59. The shape of the reinforcing ribs 56 and 57 is not limited to this shape. That is, the reinforcing ribs 56 and 57 may have various shapes such as a square and a circle as long as the shape of the battery can body 50 can be reinforced to maintain the strength of the battery can body. For example, by increasing the number of bulging portions, the reinforcing ribs may be formed in a mesh shape or a matrix shape on the entire side wall portion.

  Further, in this example, inclined tapered portions 13 and 15 are formed between the reinforcing ribs 56 and 57 and the bulging portions 58 and 59. When such tapered portions 13 and 15 are provided, the strength of the boundary portion between the bulging portions 58 and 59 and the reinforcing ribs 56 and 57 is increased. As a result, the reinforcing strength of the battery can by the reinforcing ribs 56 and 57 is increased. Can be high.

  3 and 4 are diagrams showing the configuration of the second embodiment of the large-capacity lithium ion battery of the present invention. 3 and 4, components that are the same as those in FIGS. 1 and 2 are denoted by reference numerals obtained by adding 100 to the reference numerals attached to FIGS. 1 and 2, and description thereof is omitted. As shown in FIGS. 3 and 4, in the second embodiment, bulging portions 158A and 158B are formed in two portions 151A and 151B of one opposing wall portion 151 by press working, respectively. One opposing wall 151 is configured with a reinforcing rib 156 so as to surround the periphery of the two bulging portions 158A and 158B. In addition, bulging portions 159A and 159B are also formed at two portions 152A and 152B of the other opposing wall portion 152, respectively. A reinforcing rib 157 is formed on the other opposing wall 152 so as to surround the two bulged portions 159A and 159B. Thus, the bulging part for constituting the reinforcing rib can be formed not only at one part of the side wall part but also at a plurality of parts as shown in FIG. In the second embodiment, since the reinforcing ribs are provided so as to surround the two bulging portions formed on the one opposing wall portion, the reinforcing rib is disposed at the central portion of the opposing wall portion. It will be formed to cross. Therefore, in the second embodiment, the strength of the battery can body is further increased as compared with the first embodiment shown in FIG. 1 (a structure in which one bulge portion is provided on one side wall portion). Can be high.

  5 and 6 are diagrams showing the configuration of the third embodiment of the large-capacity lithium ion battery of the present invention. 5 and FIG. 6, components that are the same as those in FIG. 1 and FIG. 2 are given the reference numerals used in FIG. 1 and FIG. As shown in FIGS. 5 and 6, in the third embodiment, the bulging portions 258A, 258B, 258C, and 258C are respectively formed on the four portions 251A, 251B, 251C, and 251D of the one opposing wall portion 251 by pressing. 258D is formed. One opposing wall 251 is provided with reinforcing ribs 256 so as to surround the four bulging portions 258A, 258B, 258C, and 258D. In addition, bulging portions 259A, 259B, 259C, and 259D are also formed in the four portions 252A, 252B, 252C, and 252D of the other opposing wall portion 252, respectively. The other opposing wall 152 is also provided with a reinforcing rib 257 so as to surround the four bulging portions 259A, 259B, 259C, and 259D. Thus, when providing the bulging part for comprising a reinforcing rib in several places, as shown in FIG. 2, it forms in four parts not only in two parts with respect to one side wall part. can do. In the third embodiment, since the reinforcing ribs are provided so as to surround the four bulged portions formed on one side wall portion, the reinforcing rib has a cross-shaped central portion of the side wall portion. It will be formed so as to intersect. Therefore, in the third embodiment, the strength of the battery can body is further increased as compared with the second embodiment shown in FIG. 2 (a structure in which two bulges are provided on one side wall). Can be high.

  FIGS. 7A to 7G are diagrams showing the configuration of the fourth embodiment of the large-capacity lithium ion battery of the present invention. In FIG. 7, components that are the same as those in FIG. 2 are denoted by reference numerals obtained by adding 300 to the reference numerals used in FIG. 2, and description thereof is omitted. In the fourth embodiment shown in FIG. 7, one bulging portion 358, 359 and three reinforcing ribs 356A, 356B, 356C and 357A, 357B, 357C are formed on the opposing wall portions 351, 352, respectively. Yes. Specifically, the pattern P4 of the bulging portions 358 and 359 is formed such that reinforcing ribs 356A and 357A are formed outside the substantially rectangular bulging portions 358 and 359, and substantially inside the bulging portions 358 and 359, respectively. The pattern shape is determined so that two square reinforcing ribs 356B and 356C and 357B and 357C (one or more reinforcing ribs) are formed.

  In the fourth embodiment, the two reinforcing ribs 356B, 365C, 357B, 357C formed inside the bulging portions 358, 359 have two non-bulging portions that do not bulge toward the electrode plate group side. Configure. In the fourth embodiment, since the three reinforcing ribs 356A, 356B, 356C and 357A, 357B, 357C can be distributed and arranged over the entire opposing wall portions 351, 352, the strength of the battery can 305 is increased. can do.

  FIGS. 8A to 8G are diagrams showing the configuration of the fifth embodiment of the large-capacity lithium ion battery of the present invention. In FIG. 8, components that are the same as those in FIG. 2 are denoted by reference numerals obtained by adding 400 numbers to the reference numerals used in FIG. 2, and description thereof is omitted. In the fifth embodiment shown in FIG. 8, one bulging portion 458, 459 and two reinforcing ribs 456A, 456B and 457A, 457B are formed on the opposing wall portions 451, 452, respectively. Specifically, the shape of the pattern P51 of the bulging portions 458 and 459 is such that reinforcing ribs 456A and 457A are formed outside the X-shaped bulging portions 458 and 459, and the X-shaped bulging portion 458 is formed. , 459, the pattern shape is determined so that substantially circular reinforcing ribs 456B and 457B (one reinforcing rib) are formed in a substantially central portion inside the.

  In the fifth embodiment, one reinforcing rib 456B, 457B formed inside the bulging portions 458, 459 constitutes one non-bulging portion that does not bulge to the electrode plate group side. In the fifth embodiment, since the two reinforcing ribs 456A, 456B, 457A, and 457B can be distributed and arranged over the entire opposing wall portions 451 and 452, the strength of the battery can 405 can be increased. . In the fifth embodiment, the shape of the bulging portions 458 and 459 is changed to an X shape, and then the portion where the X-shaped bulging portions 458 and 459 intersect (the center of the bulging portions 458 and 459). Portion) has a substantially circular non-bulged portion (reinforcing ribs 456B and 457B). As a result, when the inside of the battery can 405 is expanded, the bulging portions 458 and 459 are not easily deformed after absorbing the expanded portion, so that the deformation of the battery can 405 can be reduced.

  FIGS. 9A to 9G are diagrams showing the configuration of the sixth example of the large-capacity lithium ion battery of the present invention. In FIG. 9, components that are the same as those in FIG. 2 are denoted by reference numerals obtained by adding the number of 500 to the reference numerals used in FIG. In the sixth embodiment shown in FIGS. 9A to 9F, five bulged portions 558A, 558B, 558C, 558D, 558E and 559A, 559B, 559C, 559D, 559E are formed on the opposing wall portions 551,552. And one reinforcing rib 556 and 557 are formed. Specifically, five locations (two or more locations) of the opposing wall portions 551 and 552 are formed by bulging to the electrode plate group side with three patterns P61, P62, and P63 (two or more patterns). Three reinforcing ribs 556, 557 are formed continuously around the bulging portions 558A, 558B, 558C, 558D, 558E and 559A, 559B, 559C, 559D, 559E (two or more bulging portions). The shapes of the two patterns P61, P62, and P63 are determined. Of the five bulged portions 558A, 558B, 558C, 558D, 558E and 559A, 559B, 559C, 559D, 559E, the bulged portions 558A, 558B, 558E and 559A, 559B, 559E are substantially rectangular opposing wall portions 551. , 552 in the longitudinal direction, the two bulged portions 558A, 558B and 559A, 559B having substantially isosceles triangles are arranged so as to sandwich the substantially circular bulged portions 558E and 559E, and the bulged portions 558C, 558D, 558E and 559C, 559D, 559E are two bulged portions 558C, which are substantially isosceles triangles having a shape different from the bulged portions 558A, 559A in a direction orthogonal to the longitudinal direction of the substantially rectangular opposing wall portions 551, 552. 558D and 559C, 559D are arranged side by side so as to sandwich the substantially circular bulges 558E, 559E. It is formed in a part 551, 552.

  In the sixth embodiment, one continuous reinforcing rib 556, 557 is arranged in an X shape on the opposing wall portions 551, 552, and one reinforcing rib 556, 557 is disposed on the entire opposing wall portions 651, 652. Since the battery can 505 is arranged with good balance, the strength of the battery can 505 can be increased. In the sixth embodiment, the five bulging portions 558A, 558B, 558C, 558D, and 558E and 559A, 559B, 559C, 559D, and 559E are formed dispersedly across the opposing wall portions 551 and 552. The five bulging portions 558A, 558B, 558C, 558D, 558E and 559A, 559B, 559C, 559D, 559E can absorb the expansion of the battery can 505 with good balance.

  FIG. 10 is a diagram showing a configuration of a seventh example of the large-capacity lithium ion battery of the present invention. In FIG. 10, components that are the same as those in FIG. 2 are denoted by reference numerals obtained by adding 600 to the reference numerals used in FIG. In the seventh embodiment shown in FIGS. 10A to 10F, two bulging portions 658A, 658B and 659A, 659B and two reinforcing ribs 656A, 656B and 657A, 657B are formed. Specifically, of the two bulging portions 658A, 658B and 659A, 659B formed by bulging two portions of the opposing wall portions 651, 652 to the electrode plate group side by two patterns P71, P72, One reinforcing rib 656A, 657A is formed around the portions 658A, 659A, and between the bulging portions 658A, 659A and the bulging portions 658B, 659B formed inside the bulging portions 658A, 659A. Two patterns P71 and P72 are formed such that one continuous reinforcing rib 656B and 657B is formed, and another bulging portion 658A and 659A is formed concentrically outside the one bulging portion 658B and 659B. The shape is determined.

  In the seventh embodiment, since the other reinforcing ribs 656B and 657B are formed concentrically with the strong ribs 656A and 657A inside the reinforcing ribs 656A and 657A, the two reinforcing ribs 656A and 656B are formed. As a result, the strength of the battery can 505 can be increased. In the seventh embodiment, since one other bulging portion 658A, 659A is formed concentrically outside one bulging portion 658B, 659B, two bulging portions 658A, 658B, 659A are formed. , 659B are formed to be dispersed throughout the opposing wall portions 651, 652, so that the two bulging portions 658A, 658B, 659A, 659B can absorb the expansion of the battery can 605 in a well-balanced manner.

  As shown in FIGS. 8E, 8F, and 9G, and FIGS. 9E, 9F, and 9G, the fifth and sixth embodiments of the present invention are used. Then, a pair of side wall portions 453, 454 and 553, 554 of the battery cans 405, 505 which are orthogonal to the stacking direction of the electrode plate group and are continuous with the pair of opposing wall portions 451, 452 and 551, 552 are respectively used for reinforcement. Side wall ribs 461, 462 and 561, 562 are integrally formed by press molding. Specifically, three bulged portions 463A and 463B formed by bulging two or more portions of the side wall portions 453, 454 and 553, 554 to the electrode plate group side with two patterns P52, P53, P64, and P65. , 463C, 464A, 464B, 464C and 563A, 563B, 563C, 564A, 564B, 564C, and two patterns P52, P53 so that one reinforcing side wall ribs 461, 462 and 561, 562 are formed continuously. And the shape of P64 and P65 is defined. The three bulging portions 463A, 463B, 463C, 464A, 464B, 464C and 563A, 563B, 563C, 564A, 564B, 564C are substantially isosceles in the longitudinal direction of the substantially rectangular side wall portions 453, 454 and 553, 554. Two bulged portions 463A, 463B, 464A, 464B and 563A, 563B, 564A, 564B of the triangle are arranged side by side so as to sandwich the substantially circular bulged portions 463C, 464C, 563C, 564C, and the side wall portions 453, 454 And 553, 554.

  In the fifth and sixth embodiments, reinforcing ribs 456, 457 and 556, 557 are formed on a pair of opposing wall portions 451, 452 and 551, 552, and then a pair of side wall portions 453. Since the reinforcing side wall ribs 461, 462 and 561, 562 are also formed in 454 and 553, 554, the strength of the battery can can be reliably increased. Only the fifth embodiment and the sixth embodiment adopt the configuration in which the reinforcing side wall ribs are formed on the pair of side wall portions. However, the side wall ribs are also formed on the pair of side wall portions in the other embodiments. Of course, it may be provided.

  In order to facilitate understanding of the external structure of the battery, FIGS. 11A to 11F are a front view, a rear view, a plan view, and a bottom view of the large-capacity lithium ion battery according to the first embodiment. FIG. 11 (G) is a cross-sectional view taken along the line XIG-XIG in FIG. 11 (A) in which the internal mechanism is omitted and the thickness of a part of the battery can is emphasized. 12 is a perspective view of the lithium ion battery according to the first embodiment. 13A to 13F are a front view, a rear view, a plan view, a bottom view, a right side view, and a left side view of the large capacity lithium ion battery according to the second embodiment. G) is a cross-sectional view taken along the line XIIIG-XIIIG in FIG. 13A in which the internal mechanism is omitted and the thickness of a part of the battery can is emphasized. FIG. 14 shows the lithium ion battery according to the second embodiment. A perspective view is shown. 15A to 15F are a front view, a rear view, a plan view, a bottom view, a right side view, and a left side view of the large capacity lithium ion battery according to the third embodiment. G) is a cross-sectional view taken along the line XVG-XVG in FIG. 15A in which the internal mechanism is omitted and the thickness of a part of the battery can is emphasized, and FIG. 16 shows the lithium ion battery according to the third embodiment. A perspective view is shown.

  Further, FIGS. 17A to 17F are a front view, a rear view, a plan view, a bottom view, a right side view, and a left side view of the large capacity lithium ion battery according to the fourth embodiment. FIG. 17G is a cross-sectional view taken along the line XVIIG-XVIIG in FIG. 18 (A) to (F) are a front view, a rear view, a plan view, a bottom view, a right side view, and a left side view of the large capacity lithium ion battery according to the fifth embodiment. G) is a cross-sectional view taken along line XVIIIG-XVIIIG in FIG. 19A to 19F are a front view, a rear view, a plan view, a bottom view, a right side view, and a left side view of the large capacity lithium ion battery according to the sixth embodiment, and FIG. ) Shows a cross-sectional view taken along the line XIXG-XIXG in FIG. 20A to 20F are a front view, a rear view, a plan view, a bottom view, a right side view, and a left side view of the large-capacity lithium ion battery according to the seventh embodiment, and FIG. ) Shows a cross-sectional view taken along the line XXG-XXG in FIG.

  As mentioned above, although embodiment of this invention and embodiment were described concretely, this invention is not limited to these embodiment, The change based on the technical idea of this invention is possible. Of course.

  According to the present invention, the reinforcing ribs are integrally formed by press molding on the pair of side walls located in the stacking direction of the electrode plate group of the battery can, so that the battery can can be reinforced in the conventional manner. It is not necessary to increase the thickness of the material forming the battery can. In addition, the strength of the battery can can be increased without significantly increasing the manufacturing cost of the battery.

1,101,201,301,401,501,601 Lithium ion battery 3,103,203 Electrode group 31,31,231 Electrode plate 32,132,232,332,432,532,632 Cathode terminal 33,133 233, 333, 433, 533, 633 Negative terminal 34, 35, 134, 135, 234, 235 Nut 5, 105, 205, 305, 405, 505, 605 Battery can 50, 150, 250, 350, 450, 550, 650 Battery can body 50A, 150A, 250A Openings 51, 52, 151, 152, 251, 252, 351, 352, 451, 452, 551, 552, 651, 652 Opposing walls 53, 54, 153, 154, 253 254,353,354,453,454,553,554,653,65 Side wall part 55,155,255,355,455,555,655 Bottom wall part 56,57,156,157,256,257,356A, 356B, 356C, 357A, 357B, 357C, 456A, 456B, 457A, 457B, 556, 557, 656A, 656B, 657A, 657B reinforcing ribs 58, 59, 158, 159, 258, 259, 358, 359, 458, 459, 558A, 558B, 558C, 558D, 558E, 559A, 559B, 559C, 559D, 559E bulging part 7, 107, 207, 307, 407, 507, 607 Battery cover 71, 171, 271, 371, 471, 571, 671 Safety valve 9, 11, 109, 111, 209, 211, 309, 311 , 409, 411, 509, 511, 6 09,611 Injection port 13,15,113,115,213,215 Tapered part

Claims (8)

A large-capacity lithium ion battery in which a laminated electrode plate group in which a plurality of electrode plates are stacked is housed in a metal battery can,
A large-capacity lithium ion battery in which reinforcing ribs are integrally formed by press molding on a pair of opposing wall portions positioned in the stacking direction of the electrode plate group of the battery can.   2. The large capacity according to claim 1, wherein the reinforcing rib is formed around one bulging portion formed by bulging one portion of the opposing wall portion to the electrode plate group side in one pattern. Lithium ion battery.   The large capacity lithium ion battery according to claim 2, wherein the one place is a central region of the facing wall portion.   The pattern is defined such that one reinforcing rib is formed outside the one bulging portion, and one or more reinforcing ribs are formed inside the bulging portion. Item 3. A large-capacity lithium ion battery according to Item 2.   One reinforcing rib is formed continuously around two or more bulging portions formed by bulging two or more portions of the opposing wall portion toward the electrode plate group in two or more patterns. The large capacity lithium ion battery according to claim 1, wherein the shape of the two or more patterns is defined.   One reinforcing rib is formed between the two bulging portions formed by bulging two portions of the opposing wall portion toward the electrode plate group in two patterns, and the one bulging portion is formed. The large capacity lithium ion battery according to claim 1, wherein the shapes of the two patterns are determined so that another one of the bulging portions is formed concentrically outside the protruding portion.   The reinforcing side wall ribs are integrally formed by press molding on the pair of side wall portions of the battery can perpendicular to the stacking direction of the electrode plate group and continuous with the pair of opposing wall portions. 7. The large capacity lithium ion battery according to any one of items 1 to 6.   One reinforcing side wall rib is formed continuously around the two or more bulging portions formed by bulging two or more portions of the side wall portions to the electrode plate group side in two or more patterns. The high capacity lithium ion battery according to claim 7, wherein the shape of the two or more patterns is defined.

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