JP2017027952A - battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent increase in electric resistance of a battery by improving vibration resistance and impact resistance of a collector provided in the battery.SOLUTION: An anode collector 12 comprises: a base part 31 fixed to a lid 4 of a battery 1 and electrically connected to an anode external terminal 14; and leg parts 32 protruding from the base part 31 and electrically connected to an anode 5 of a power generating element 3. A rib 37 protruding in the same direction as the leg parts 32 is provided along at least part of an outer peripheral edge of the base part 31.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a battery and a current collector.

  A battery such as a nonaqueous electrolyte secondary battery includes positive and negative current collectors for electrically connecting the positive electrode and the negative electrode of the power generation element to positive and negative external terminals, respectively. The current collector is fixed to the battery lid by means such as caulking using rivets (see, for example, Patent Document 1).

JP 2010-212111 A

  In particular, in a non-aqueous electrolyte secondary battery for vehicles such as electric vehicles, the current collector is required to have long-term vibration resistance and impact resistance. However, in the conventional battery, sufficient consideration and examination are not made on the vibration resistance and impact resistance of the current collector. For this reason, when a conventional battery is used for a long period of time in an environment where vibration and impact act, the electrical resistance increases due to insufficient vibration resistance and impact resistance of the current collector.

  An object of the present invention is to prevent an increase in electrical resistance by improving the vibration resistance and impact resistance of a current collector in a battery.

  A first aspect of the present invention is a battery including a current collector that electrically connects a power generation element disposed inside an exterior body and an external terminal at least partially disposed outside the exterior body. The current collector includes a base portion that is electrically connected to the external terminal, a connection portion that protrudes from the base portion and is electrically connected to the power generation element, and a rib provided on the base portion. Provide batteries.

  Specifically, the rib is provided along at least a part of the outer peripheral edge of the base.

  Preferably, the rib is formed by drawing the base.

  By forming the ribs by drawing, work hardening occurs in the base portion of the current collector, particularly around the ribs, and the yield stress increases locally. Therefore, plastic deformation of the base portion of the current collector can be suppressed. Therefore, the vibration resistance and impact resistance of the current collector are further improved by forming the ribs by drawing.

  More specifically, the rib includes a main portion protruding from the base portion in the same direction as the connection portion.

  By providing the rib having such a main portion, the section modulus and pole section modulus of the base portion of the current collector are increased, so that the strength of the base portion of the current collector against bending and torsion due to vibration and impact is improved. As a result, the vibration resistance and impact resistance of the current collector are improved, and an increase in electrical resistance can be prevented.

  It is preferable that the rib further includes an extension part protruding from the tip of the main part.

  By providing the extension at the tip of the main part, the section modulus and pole section modulus of the base of the current collector are further increased, so that the strength of the base of the current collector against bending and twisting due to vibration and impact is further improved. As a result, the vibration resistance and impact resistance of the current collector are further improved, and an increase in electrical resistance can be prevented more reliably.

Preferably, the exterior body includes a lid body having a recess formed on an inner surface, and the base portion of the current collector is disposed in the recess.
In this case, even if the base is flat, by disposing the entire base in the recess of the lid, the capacity in the battery can be increased, and alignment during manufacturing can be easily performed.

  Preferably, the exterior body includes a lid body having a recess formed on an inner surface, and the base portion of the current collector includes a first portion disposed in the recess and the lid adjacent to the recess. A second portion provided on the inner surface of the body and provided with the connecting portion; and a connecting portion for connecting the first and second portions so as to be different from each other.

  The base of the current collector is not a mere flat plate, but includes a first and a second part connected by connecting parts so as to be stepped so that the current collector against bending or twisting due to vibration or impact The strength of the base is further improved. As a result, the vibration resistance and impact resistance of the current collector are further improved, and an increase in electrical resistance can be prevented more reliably. Moreover, the mounting strength of the current collector with respect to the battery lid is improved by arranging the first portion of the uneven base portion in the concave portion of the lid and the second portion on the lower surface of the lid, Also in this respect, the vibration resistance and impact resistance of the current collector are enhanced. Thus, by further improving the vibration resistance and impact resistance, an increase in electrical resistance can be prevented more reliably.

  In this case, it is preferable that the main portion of the rib is provided on a portion of the outer peripheral edge of the first portion of the base portion excluding a portion connected to the connecting portion. Since the first portion of the base portion of the current collector has a shallow tray shape, the strength of the base portion against bending and twisting can be improved by this shape and by vibration and impact.

  In particular, the connecting portion is preferably connected to the extension portion of the rib. In this case, the main part of the rib is further provided in the second part of the base part, and the extension part of the rib is connected to the second part side of the first part and the second part of the base part. 2 is preferably provided. With this configuration, since the length of the connecting portion between the connecting portion and the base portion of the current collector is extended, the rigidity of the current collector as a whole is improved, and the strength against bending and torsion is further improved due to vibration and impact.

  According to a second aspect of the present invention, there is provided a current collector for electrically connecting a power generation element disposed inside a battery exterior body and an external terminal at least partially disposed outside the exterior body. A current collector is provided that includes a base connected to the external terminal, a connection protruding from the base and connected to the power generation element, and a rib provided on the base.

  According to the present invention, the current collector that electrically connects the power generation element of the battery and the external terminal includes the rib on the base that is fixed to the exterior body and electrically connected to the external terminal. Therefore, since the section modulus and polar section modulus of the base of the current collector are increased, the strength of the base of the current collector is improved against bending and torsion due to vibration and impact, and high vibration resistance and impact resistance can be obtained. Thus, an increase in electrical resistance can be prevented. In particular, by forming ribs by drawing, plastic deformation of the base can be suppressed, vibration resistance and impact resistance of the current collector can be further improved, and an increase in electrical resistance can be more reliably prevented.

The partial cross section front view of the battery which concerns on 1st Embodiment of this invention. The perspective view which looked at the lid of Drawing 1 from the upper part. FIG. 3 is an exploded perspective view of FIG. 2. The perspective view which looked at the lid of Drawing 1 from the lower part. The partial expansion perspective view which made the negative electrode electrical power collector which concerns on 1st Embodiment of this invention the posture upside down. The partial expansion perspective view which looked at the negative electrode electrical power collector concerning a 1st embodiment of the present invention from the other direction as an upside down posture. The partial expansion perspective view which made the positive electrode electrical power collector which concerns on 1st Embodiment of this invention the posture upside down. The partial expansion perspective view which looked at the positive electrode electrical power collector which concerns on 1st Embodiment of this invention from the other direction as an upside down attitude | position. The partial expansion perspective view which made the negative electrode electrical power collector which concerns on 2nd Embodiment of this invention the posture upside down. The partial expansion perspective view which looked at the negative electrode electrical power collector concerning a 2nd embodiment of the present invention from the other direction as an upside down posture. The partial expansion perspective view which looked at the negative electrode electrical power collector concerning a 2nd embodiment of the present invention from the other direction as an upside down posture. The partial expansion perspective view which made the positive electrode electrical power collector which concerns on 2nd Embodiment of this invention the posture upside down. The partial expansion perspective view which looked at the positive electrode electrical power collector which concerns on 2nd Embodiment of this invention from the other direction as an upside down attitude | position. The partial expansion perspective view which looked at the positive electrode electrical power collector concerning a 2nd embodiment of the present invention from the other direction as a posture reversed upside down. The partial expansion perspective view which made the negative electrode electrical power collector of a comparative example the posture upside down. The graph which shows the relationship between a test frequency and resistance change rate.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

(First embodiment)
FIG. 1 shows a nonaqueous electrolyte secondary battery 1 (hereinafter simply referred to as a battery) according to a first embodiment of the present invention. The battery 1 is made of aluminum, an aluminum alloy, or the like, in which a power generating element 3 is accommodated in a rectangular battery container 2 and the upper end opening of the battery container 2 is sealed with a lid 4. The battery case 2 and the lid 4 constitute an exterior body. The upper surfaces of the negative external terminal 14 and the positive external terminal 15 are exposed to the outside of the lid 4.

  In the power generation element 3, a separator 7 made of a porous resin film is disposed between a negative electrode 5 made of copper foil and a positive electrode 6 made of aluminum foil. These are all belt-like, and are wound in a flat shape with the negative electrode 5 and the positive electrode 6 being shifted from each other on the opposite side in the width direction with respect to the separator 7. In the power generation element 3, the negative electrode 5 is electrically connected to the negative electrode external terminal 14 via the negative electrode current collector 12, and the positive electrode 6 is electrically connected to the positive electrode external terminal 15 via the positive electrode current collector 13. .

  2 to 4 together, the lid 4 is a long metal plate having a rectangular shape in plan view, and a safety valve 8 is mounted near the center in the longitudinal direction, and a liquid injection hole 9 is provided on one end side. Is provided.

  At both end portions of the lid body 4, engagement receiving portions 11 having a substantially rectangular shape in plan view that bulge upward from the upper surface 4 b are formed. In each engagement receiving part 11, the lower surface 4a of the cover body 4 is recessed, and the engagement recessed part 11a is formed. Further, a shallow guide recess 11b is formed on the lower surface 4a of the lid 4 around the periphery of the engagement recess 11a except for one side. Further, a through hole 11c is formed in the central portion of the ceiling surface constituting the engaging recess 11a.

  In the drawing, a negative electrode current collector 12 and a negative electrode external terminal 14 are attached to an engagement receiving portion 11 and a guide recess 11b on the left side via an upper packing 16 and a negative electrode lower packing 17, respectively.

  The upper packing 16 is a resin part that partitions the upper terminal holding recess 16b and the lower mounting recess 16c by a partition wall 16a. The center portion of the partition wall 16a has both end openings extending downward. A cylindrical portion 16d is provided. The upper packing 16 is mounted on the lid 4 by covering the engagement receiving portion 11 from above and housing the engagement receiving portion 11 in the mounting recess 16c. The cylindrical portion 16d is inserted into the through hole 11c and enters the locking recess 11a. Further, a locking projection 19 protruding from the upper surface 4 b of the lid 4 is inserted into the locking holes 16 f of the two tongue-like pieces 16 e provided in the upper packing 16.

  The negative electrode lower packing 17 is provided in a bulging portion 17 a disposed in the engaging recess 11 a of the lid body 4 and in a guide recess 11 b of the engagement receiving portion 11 provided continuously to the bulging portion 17 a. And a flat portion 17b. The bulging portion 17a has a shape along the inner surface of a portion of the engagement receiving portion 11 excluding one side of the engagement recess portion 11a. A through hole 17c is formed in the bulging portion 17a. Near the lower end of the cylindrical portion 16d of the upper packing 16 is inserted into the through hole 17c.

  The negative electrode external terminal 14 includes an aluminum plate 21 having a rectangular shape in plan view and a copper rivet 22. The rivet 22 is fixed to the plate-like portion 21 with the shaft portion 22b protruding by press-fitting the jaw portion 22a into a through hole 21a formed in the central portion of the plate-like body 21. The plate-like body 21 is accommodated in the terminal holding recess 16 b of the upper packing 16.

  The base 31 of the negative electrode current collector 12 is disposed so as to overlap below the bulging portion 17 a and the flat portion 17 b of the negative electrode lower packing 17. The negative electrode current collector 12 will be described later.

  After inserting the shaft portion 22b of the rivet 22 of the negative electrode external terminal 14 through the cylindrical portion 16d of the upper packing 16 and the through hole 33a formed in the base portion 31 of the negative electrode current collector 12, the tip is widened to enlarge the large diameter portion. By forming 22 c, the negative electrode external terminal 14, the upper packing 16, the negative electrode lower packing 17, and the base 31 of the negative electrode current collector 12 are caulked and fixed to the lid 4.

  In the drawing, a positive electrode current collector 13 and a positive electrode external terminal 15 are attached to an engagement receiving portion 11 and a guide recess 11b on the right side via an upper packing 16 and a positive electrode lower packing 18, respectively.

  Similar to the negative electrode side, the upper packing 16 is attached to the engagement receiving portion 11. On the other hand, the positive side lower packing 18 has a flat plate shape with a through hole 18a, and is disposed in the engaging recess 11a.

  The positive electrode external terminal 15 is made of aluminum, and includes a plate-like body 15a having a rectangular shape in plan view and a cylindrical shaft portion 15b protruding from the center portion of the lower surface. The plate-like body 15 a is accommodated in the terminal holding recess 16 b of the upper packing 16.

  The base 31 of the positive electrode current collector 13 is disposed so as to overlap the lower side of the positive electrode lower packing 18. The positive electrode current collector 13 will be described in detail later.

  The shaft portion 15b of the positive electrode external terminal 15 is inserted through the cylindrical portion 16d of the upper packing 16 and the through hole 33a formed in the base portion 31 of the positive electrode current collector 13, and then the tip is widened to form the large diameter portion 15c. By doing so, the positive electrode external terminal 28, the upper packing 16, the positive electrode lower packing 18, and the base 31 of the positive electrode current collector 13 are caulked and fixed to the lid 4.

  The negative electrode current collector 12 shown in FIGS. 5A and 5B is made of copper, and the positive electrode current collector 13 shown in FIGS. 6A and 6B is made of aluminum, both of which are manufactured by pressing a plate material. Since the negative electrode current collector 12 and the positive electrode current collector 13 have the same structure, the negative electrode current collector 12 will be described in detail below. Regarding the positive electrode current collector 13, the same or similar elements as those of the negative electrode current collector 12 are denoted by the same reference numerals, and differences from the negative electrode current collector 12 will be described.

  The negative electrode current collector 12 shown in FIGS. 5A and 5B includes a base portion 31 and a pair of leg portions (connection portions) 32 and 32. Referring also to FIG. 4, the base portion 31 is disposed in an engagement recess 11 a formed on the lower surface 4 a of the lid body 4 and is fixed so as to overlap the bulging portion 17 a of the negative electrode lower packing 17. A portion (first portion) 33 and a pedestal portion (second portion) 34 that is disposed on the lower side of the flat portion 17b of the negative electrode lower packing 17 at a position adjacent to the engaging recess 11a. When the battery 1 is arranged in the posture shown in FIG. 1, both the fixing portion 33 and the pedestal portion 34 are arranged on the horizontal plane (XY plane), but the position in the height direction (Z direction) is not the same. Instead, the fixed portion 33 and the pedestal portion 34 are arranged in a different positional relationship. Specifically, the fixing portion 33 accommodated in the engaging recess 11 a of the lid body 4 is located above the pedestal portion 34 disposed on the lower surface 4 b of the lid body 4. The fixing portion 33 and the pedestal portion 34 which are different from each other are connected by a connecting portion 35 which expands substantially along a vertical plane (YZ plane) when the battery 1 is arranged in the posture shown in FIG.

  A through hole 33 a is formed in the center of the fixing portion 33 for inserting the shaft portion 22 b of the rivet 22 of the negative electrode external terminal 14. As described above, the fixing portion 33 is caulked and fixed to the lid 4 together with the negative electrode external terminal 28, the upper packing 16, and the negative electrode lower packing 17 by the rivet 22. The fixing portion 33 is electrically connected to the plate-like body 21 of the negative electrode external terminal 14 via the rivet 22.

  The pedestal portion 34 has a generally rectangular plate shape. Of the four sides of the pedestal portion 34, a rectangular shape having a constant width from two opposite sides (two sides facing the width direction of the base portion 31) other than one side to which the fixing portion 33 is connected via the connecting portion 35. Leg portions 32, 32 protrude in parallel with each other. When the battery 1 is arranged in the posture shown in FIG. 1, the leg portions 32, 32 extend substantially downward in the vertical direction (−Z direction) from the pedestal portion 34, and are adjacent to the negative electrode 5 (copper foil) of the power generation element 3. Arranged. The legs 32 and 32 and the negative electrode 5 of the power generation element 3 are electrically connected by a clip 10 schematically shown only in FIG. 1 and mechanically coupled to each other.

  As most clearly shown in FIGS. 5A and 5B, a wall-like rib 37 is formed on the fixing portion 33 in the base portion 31 of the negative electrode current collector 12. The rib 37 rises from the base portion 31 so as to protrude in the same direction as the extending direction of the leg portions 32, 32 and the direction in which the connecting portion 35 extends from the fixed portion 33 toward the pedestal portion 34. Specifically, the rib 37 includes straight portions 37a, 37b, 37c, a straight portion 37a, and a straight portion 37c along three sides excluding one side connected to the connecting portion 35 among the four sides of the substantially rectangular fixing portion 33. An arc-shaped portion 37d that connects, and an arc-shaped portion 37e that connects the straight portion 37b and the straight portion 37c are provided. The rib 37 includes rounded portions 37f and 37g that rise from the end portions of the straight portions 37a and 37b to the pedestal portion 34. In other words, the ribs 37 are formed along the outer peripheral edge of the base portion 31 excluding the side on the connection side with the connecting portion 35.

  Further, the height H1 of the rib 37 excluding the round-shaped portions 37f and 37g (the distance from the upper surface of the fixing portion 33 to the tip surface of the rib 37 in FIG. 5A) is, for example, 1 according to the conditions such as the dimensions of the base portion 31. It is set to a range of about 10 mm. In the present embodiment, the height H1 of the rib 37 excluding the round-shaped portions 37f and 37g is substantially constant, but the height may be different for each part of the rib 37.

  Since the ribs 37 are formed on the three sides and the connecting portion 35 is connected to the other side, the fixing portion 33 has a shape like a shallow tray as a whole, and a through hole for fixing the caulking at the center thereof. 33a is located.

  By drawing the plate material, the fixing portion 33 and the pedestal portion 34 are placed at different positions via the connecting portion 35, and ribs 37 are provided along the outer peripheral edge of the fixing portion 33. In other words, at the base 31 of the negative electrode current collector 12, the fixed portion 33 is shaped like a shallow tray by drawing.

  Of the positive electrode current collector 13, the fixing portion 33 disposed in the engagement recess 11 a of the lid 4 is overlaid on the positive electrode lower packing 18, but the pedestal portion 34 disposed at a position adjacent to the engagement recess 11 a is It arrange | positions without passing the positive electrode lower packing 18 with respect to the lower surface 4a of the cover body 4 (refer FIG. 4). The leg portions 32, 32 of the positive electrode current collector 13 are electrically connected to the positive electrode 6 of the power generating element 3 by a clip 10 schematically shown only in FIG.

  When vibration or impact is applied to the battery 1, the negative electrode current collector 12 and the positive electrode current collector 13 are mainly subjected to a force in the X direction schematically indicated by an arrow F in FIGS. 2, 5A, and 6A. Act on. The reason for this is that the displacement of the power generation element 3 in the battery case 2 in the Y direction is constrained by the inner surfaces of both side walls of the battery case 2, whereas the negative current collector 12 and the positive current collector 13 are connected. This is because there is still room for the power generating element 3 to be displaced in the battery container 2 in the X direction in order to secure the space. In the present embodiment, by providing the rib 37, the fixing portion 33 (fixed to the lid body 4 by caulking) of the base 31 provided in the negative electrode current collector 12 and the positive electrode current collector 13 against bending as indicated by an arrow F. And the strength of the base 31 of the negative electrode current collector 12 and the positive electrode current collector are increased.

  In addition, referring to FIG. 1 again, since a space for filling the electrolyte is provided between the lid 4 and the power generation element 3, when vibration or impact is applied to the battery 1, There remains room for the power generating element 3 to be displaced in the battery case 2 not only in the X direction but also in the Z direction. For this reason, a force for twisting around the X axis also acts on the fixing portion 33 of the base 31 provided in the negative electrode current collector 12 and the positive electrode current collector 13. In this embodiment, by providing the rib 37, the pole section coefficient of the fixed portion 33 of the base 31 provided in the negative electrode current collector 12 and the positive electrode current collector 13 is set high with respect to this type of twist, and the negative electrode current collector The strength of the body 12 and the base 31 of the positive electrode current collector is increased.

  As described above, by providing the rib 37, the section modulus and the pole section coefficient of the base portion 31 are increased, so that the strength of the base portion 31 of the negative electrode current collector 12 and the positive electrode current collector 13 with respect to bending or twisting due to vibration or impact is increased. improves. As a result, the vibration resistance and impact resistance of the negative electrode current collector 12 and the positive electrode current collector 13 are improved. An increase in electrical resistance can be prevented by improving vibration resistance and impact resistance.

  Further, as described above, the fixing portion 33 of the base portion 31 is formed into a shallow tray shape by the ribs 37 and the connecting portions 35, but this shape also contributes to improving the strength of the base portion 31 against bending or twisting due to vibration or impact.

  Formation of the rib 37 and formation of a structure in which the fixing portion 33 and the pedestal portion 34 are stepped at the connecting portion 35 are performed by drawing the fixing portion 33 of the base 31. By forming the ribs 37 by drawing, work hardening occurs in the base 31 particularly in the vicinity of the ribs 37 and the yield stress increases locally. Therefore, the base 31 of the negative electrode current collector 12 and the positive electrode current collector 13 is increased. Plastic deformation can be suppressed. That is, since the ribs 37 are formed by drawing, the vibration resistance and impact resistance of the negative electrode current collector 12 and the positive electrode current collector 13 are further improved, and an increase in electrical resistance can be prevented more reliably. .

  The base 31 is not simply a flat plate, but the fixed portion 33 and the pedestal 34 are connected by a connecting portion 35 so that the negative electrode current collector 12 and the positive electrode current collector against bending and torsion due to vibration and impact are also included. The strength of the base portion 31 of the body 13 is increased, which contributes to the improvement of the vibration resistance and impact resistance of the negative electrode current collector 12 and the positive electrode current collector 13 and the prevention of an increase in electric resistance.

  Further, among the bases 31 having different levels, the fixing part 33 is disposed in the engaging recess 11 a of the lid body 4, and the pedestal part 34 is disposed on the lower surface 4 a of the lid body 4. The mounting strength of the current collector 12 and the positive electrode current collector 13 is improved, and in this respect as well, vibration resistance and impact resistance are increased, and an increase in electrical resistance can be prevented.

(Second Embodiment)
The second embodiment of the present invention shown in FIGS. 7A to 8C includes the structure of the copper negative electrode current collector 12 itself shown in FIGS. 7A to 7C and the aluminum positive electrode current collector 13 shown in FIGS. 8A to 8C. The structure itself is different from the first embodiment. Other structures of the battery 1, particularly a connection structure of the negative and positive current collectors 12 and 13 to the power generation element 3 and the negative and positive external terminals 14 and 15, and attachment of the negative and current collectors 12 and 13 to the lid 4 The structure is the same as in the first embodiment. Moreover, since the negative electrode current collector 12 and the positive electrode current collector 13 of the present embodiment also have the same structure, the negative electrode current collector 12 will be described in detail below. Regarding the positive electrode current collector 13, the same or similar elements as those of the negative electrode current collector 12 are denoted by the same reference numerals, and differences from the negative electrode current collector 12 will be described.

  In the negative electrode current collector 12 shown in FIGS. 7A to 7C, the rib 37 has a wall-shaped main portion 37 h and a pair of extension portions 37 i and 37 j that protrude laterally outward (Y direction in the drawing) from the tip of the main portion 37 h. Prepare. Note that the ribs 37 of the negative electrode and positive electrode current collectors 12 and 13 of the first embodiment correspond to a configuration including only the main portion 37h of the ribs 37 of the present embodiment.

  A main portion 37 h of the rib 37 is provided in the fixing portion 33, the pedestal portion 34, and the connecting portion 35 in the base portion 31 of the negative electrode current collector 12. First, in the substantially rectangular fixing portion 33, the main portion 37h of the rib 37 is a straight portion 37a, 37b, 37c, a straight portion 37a and a straight portion along three sides excluding one side connected to the connecting portion 35 among the four sides. An arc-shaped portion 37d that connects 37c and an arc-shaped portion 37e that connects the straight portion 37a and the straight portion 37c are provided. Further, in the substantially rectangular plate-like pedestal portion 34, the main portion of the rib 37 on two opposite sides (two sides facing the width direction of the base portion 31) other than the one side to which the fixing portion 33 is connected via the connecting portion 35. 37h straight portions 37k and 37m are provided. Further, on two opposite sides of the connecting portion 35 (two sides facing the width direction of the base portion 31), straight portions 37a and 37b provided on the fixed portion 33 and straight portions 37k provided on the pedestal portion 34, Linear portions 37n and 37p are provided so as to connect 37m.

  In this embodiment, the wall-like main portion 37h of the rib 37 is also provided on the pedestal portion 34 and the connecting portion 35, so that not only the fixing portion 33 but also the pedestal walking 34 and the connecting portion 35 have a high section coefficient and polar section coefficient. In this respect, the strength of the negative electrode current collector 12 can be increased.

  Of the main portion 37h of the rib 37, linear portions 37a and 37b provided on the fixed portion 33 and facing each other, linear portions 37n and 37p provided on the connecting portion 35 continuous with the linear portions 37a and 37b, and these The extension portions 37i and 37j described above are provided on the straight portions 37k and 37m provided on the pedestal portion 34 continuous with the straight portions 37n and 37p. In the linear portions 37a and 37b facing each other provided in the fixing portion 33, the extension portions 37i and 37j are not extended from the entire length, but extended from the connecting portion 35 to a portion near the position corresponding to the center of the through hole 33a (the connecting portion 35 side). Is provided. In short, the extension portions 37 i and 37 j facing each other extend from the end portion of the pedestal portion 34 to the middle of the fixing portion 33.

  By providing the extension portions 37i and 37j at the tip of the main portion 37h of the rib 37, the section modulus and pole section modulus of the base 31 of the anode current collector 12 are further increased, so that the anode current collector against bending and torsion due to vibration and impact is increased. The strength of the base 31 of the body 12 is further improved. As a result, the vibration resistance and impact resistance of the negative electrode current collector 12 are further improved, and an increase in electrical resistance can be prevented more reliably.

  The pair of leg portions 32, 32 of the negative electrode current collector 12 protrude from the extension portions 37i, 37j. Specifically, these leg portions 32 and 32 are fixed to the extension portions 37i and 37j through the lower end side seating portion 32a, and the seating portion 32a extends over the entire length in the longitudinal direction of the extension portions 37i and 37j. It extends. That is, the portion where the pair of leg portions 32, 32 is connected to the base portion 31 extends to the middle of the fixing portion 33 (a position corresponding to the center of the through hole 33a) beyond the base portion 34. By extending the length of the seating portion 32a, which is a connecting portion between the leg portions 32, 32 and the base portion 31, the overall rigidity of the negative electrode current collector 12 is improved, and the strength against bending and twisting due to vibration and impact is further increased. improves.

  In the positive electrode current collector 13 shown in FIGS. 8A to 8C, the length of the fixing portion 33 in the longitudinal direction is set longer than that of the negative electrode current collector 12 shown in FIGS. 7A to 7C. Further, a tongue-like portion 38 extending from the upper end of the linear portion 37 c of the rib 37 is provided at the longitudinal end of the fixing portion 33. The tongue 38 is provided for welding the positive electrode current collector 13 to the lid 4.

  A test for confirming the effect of the present invention was conducted. In this test, the copper negative electrode current collector 12 shown in FIGS. 5A and 5B was used (hereinafter, this negative electrode current collector 12 will be referred to as an example if necessary). The dimensions of the negative electrode current collector 12 of the example were as follows. First, the total length L of the base 31 was 45 mm, the width W1 of the fixed portion 33 was 25 mm, and the width W2 of the pedestal portion 34 was 35 mm. Further, the height H1 of the rib 37 excluding the rounded portions 37f and 37g was 3 mm. Furthermore, in FIG. 5A, the height H2 from the upper surface of the fixed portion 33 to the lower surface of the pedestal portion 34 was 7 mm. As a comparative example, a copper negative electrode current collector 12 ′ shown in FIG. 9 was prepared. The negative electrode current collector 12 ′ of the comparative example has the same dimensions as the negative electrode current collector 12 of the example, but the base portion 33 ′ in which the through holes 33a ′ for caulking are formed is a flat plate shape, and the ribs are It is not formed and has no uneven structure.

  The test conditions for vibration resistance and impact resistance specified in the UN (UN) test standard manual were repeated three times to measure the rate of change in battery resistance. The test results are shown in Table 1 below and FIG. In FIG. 10, a circle mark is a comparative example and a square mark is an example.

  As apparent from Table 1 and FIG. 10, in the comparative example, the resistance increased from 100% to 10% before and after the test to 110%, whereas in the example, the resistance increased from 100% to 5% before and after the test. It became 105%. From this result, it can be confirmed that the vibration resistance and impact resistance of the current collector are improved by the present invention, thereby preventing an increase in electrical resistance.

The present invention is not limited to the above embodiment, and various modifications can be made.
Even if a rib similar to the rib 37 is provided on the outer peripheral edge of a simple flat plate-like base as in the comparative example shown in FIG. 9, the strength of the base of the current collector is increased to improve vibration resistance and impact resistance. Can be improved. In the case of a current collector having such a flat base, the entire base may be accommodated in the recess of the lid 4. Even in this case, the capacity in the battery can be increased, and alignment during manufacture is easy.
Moreover, although the present invention has been described by taking a non-aqueous electrolyte secondary battery as an example, the present invention can be applied to batteries other than the non-aqueous electrolyte secondary battery.

DESCRIPTION OF SYMBOLS 1 Nonaqueous electrolyte secondary battery 2 Battery container 3 Electric power generation element 4 Lid 4a Lower surface 4b Upper surface 5 Negative electrode 6 Positive electrode 7 Separator 8 Safety valve 9 Injection hole 10 Clip 11 Engagement receiving part 11a Engaging recessed part 11b Guide recessed part 11c Through-hole 12 Negative electrode current collector 13 Positive electrode current collector 14 Negative electrode external terminal 15 Positive electrode external terminal 15a Plate 15b Shaft portion 15c Large diameter portion 16 Upper packing 16a Partition 16b Terminal holding recess 16c Mounting recess 16d Cylindrical portion 16e Tongue 16f Engagement hole 17 negative electrode lower packing 17a bulging portion 17b flat portion 17c through hole 18 positive electrode lower packing 19 locking projection 21 plate-like body 21a through hole 22 rivet 22a jaw portion 22b shaft portion 22c large diameter portion 31 base portion 32 leg portion 32a Seating part 33 Fixing part 33a Through hole 34 Base part 35 Connection part 37 Rib 37a, 37b, 37c Straight part 37d, 37e Arc part 37f, 37g Earl part 37h Main part 37i, 37j Extension part 37k, 37m Straight part (pedestal part)
37n, 37p straight part (connecting part)
38 Tongue

The present invention also relates to the battery.

The present invention provides a current collector that electrically connects a power generation element disposed inside an exterior body and an external terminal at least part of which is disposed outside the exterior body, and the exterior body and the current collector. The current collector is electrically connected to the power generation element by projecting from the base and a base part electrically connected to the external terminal. And a rib provided on the base, and the lower packing includes a bulging portion on which the base including the rib is disposed .

Preferably, the exterior body includes a lid body having a recess formed on an inner surface, and the base portion of the current collector is disposed in the recess . In this case, even the base is flat, by arranging the entire base in the recess of the lid, it is possible to increase the capacity of the battery, can be aligned at the time of manufacture can be easily performed .

Claims (11)

A battery comprising a current collector that electrically connects a power generation element disposed inside an exterior body and an external terminal at least a part of which is disposed outside the exterior body,
The current collector is
A base electrically connected to the external terminal;
A connecting portion protruding from the base and electrically connected to the power generating element;
A battery comprising: a rib provided on the base.   The battery according to claim 1, wherein the rib is provided along at least a part of an outer peripheral edge of the base portion.   The battery according to claim 1, wherein the rib is formed by drawing the base portion.   The battery according to any one of claims 1 to 3, wherein the rib includes a main portion protruding from the base portion in the same direction as the connection portion.   The battery according to claim 4, wherein the rib further includes an extension part protruding from a tip of the main part. The exterior body includes a lid body with a recess formed on the inner surface,
The battery according to claim 1, wherein the base of the current collector is disposed in the recess. The exterior body includes a lid body with a recess formed on the inner surface,
The base of the current collector is
A first portion disposed in the recess;
A second portion disposed on the inner side surface of the lid adjacent to the recess and provided with the connecting portion;
6. The battery according to claim 1, further comprising: a connecting portion that connects the first and second portions so as to be different from each other. The exterior body includes a lid body with a recess formed on the inner surface,
The base of the current collector is
A first portion disposed in the recess;
A second portion disposed on the inner side surface of the lid adjacent to the recess and provided with the connecting portion;
A connecting portion that connects the first and second portions so as to be inconsistent with each other. The battery according to claim 4, wherein the battery is provided in a portion excluding the portion to be operated.   The battery according to claim 8, wherein the connection portion is connected to the extension portion of the rib. The main portion of the rib is further provided in the second portion of the base;
The battery according to claim 9, wherein the extension portion of the rib is provided on the second portion side of the first portion and the second portion of the base portion. A current collector that electrically connects a power generation element disposed inside a battery exterior body and an external terminal at least partially disposed outside the exterior body,
A base connected to the external terminal;
A connecting portion protruding from the base and connected to the power generation element;
A current collector comprising: a rib provided on the base.

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