JP5326125B2 - Nonaqueous electrolyte secondary battery - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce the parts number for parts to taking out an electric current, and improve the electric performance and the mechanical performance of electrode terminal portions. <P>SOLUTION: A penetrating terminal member 15 and an upper plate 11 of a current collector 7 are integrally formed by fusing the penetrating terminal member 15 on the upper plate 11 by friction gripping. The penetrating terminal member 15 and a long joining plate 12 connected to an electrode group are constructed of one member so that the parts member is reduced and the electric and mechanical performances are improved. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a non-aqueous electrolyte secondary battery, and more particularly, to a non-aqueous electrolyte secondary battery that achieves a structure of an electrode terminal mounting portion intended for high performance and high reliability.

  Non-aqueous electrolyte secondary batteries are characterized by having a high voltage and high energy density. Therefore, non-aqueous electrolyte secondary batteries can be put into practical use for power storage, electric vehicles, hybrid electric vehicles, trains, etc. Promising.

  A nonaqueous electrolyte secondary battery includes an electrode body in which a positive electrode plate and a negative electrode plate are laminated via a separator, an electrode body obtained by winding a positive electrode plate and a negative electrode plate via a separator, and a nonaqueous electrolyte in a battery case. It has a housed structure. In the non-aqueous electrolyte secondary battery, the extraction of current from the electrode body is performed through current collectors connected to the positive electrode plate and the negative electrode plate, respectively. That is, the current collector is fixed to the end of the electrode body, and the positive electrode terminal and the negative electrode terminal that are electrically connected to the current collector are protruded out of the battery case (see, for example, Patent Document 1).

  In a conventionally proposed nonaqueous electrolyte secondary battery, a rivet terminal is fixed to a current collector and protruded to the outside of the battery case, and a terminal member (positive electrode terminal, negative electrode terminal) is connected to the rivet terminal located outside the battery case. ) Is fixed. The current collector, rivet terminal, and terminal member are separate parts, and one end of the rivet terminal is caulked and fixed to the current collector, and the other end side of the rivet terminal is passed through the battery case and protrudes outside the battery case. The other end of the rivet terminal is caulked and fixed to the terminal member. A seal packing is interposed between the battery case and the current collector, and between the battery case and the rivet terminal (current collector), and a portion where the terminal member of the battery case is provided is sealed.

  In a conventional non-aqueous electrolyte secondary battery, a current collector, a rivet terminal, and a terminal member are used to extract current, and a fitting hole is formed in the current collector and the terminal member to fit the rivet terminal. Then, the rivet terminals are fitted into the fitting holes and the ends are caulked and fixed. For this reason, the number of parts has increased, and it has taken time to manage parts. In addition, since the rivet terminal is fitted into the fitting hole and fixed by caulking, the connection between the current collector and the terminal member is only in electrical contact. There is a risk that contact resistance will increase due to long-term use.

  In particular, lithium-ion batteries use aluminum that easily oxidizes the surface as a material for the current collector or electrode on the positive electrode side. Therefore, it is necessary to carry out caulking of aluminum that can accurately manage parts and maintain strength. The current situation is to suppress poor contact and the like.

  It is also considered to fix the rivet terminal by ultrasonic welding instead of caulking, but there is a limit to the thickness of the current collector etc. on the side to be fixed, and the current collector is disconnected to take out large power. When the area is increased, joining becomes difficult.

JP-A-8-77999

  The present invention has been made in view of the above situation, and has reduced the number of parts of a member for taking out current and improved the electrical performance and mechanical performance at the portion of the electrode terminal to improve reliability. An object is to provide a nonaqueous electrolyte secondary battery.

In order to achieve the above object, a nonaqueous electrolyte secondary battery of the present invention according to claim 1 includes a current collecting member provided on the inner side of the battery outer member and conducting to the electrode, and a terminal provided on the outer side of the battery outer member. comprising a member and a through terminal member provided through the battery outer members conducts and said terminal member and said collector member, said feedthrough terminal member is bonded portions by friction fixed to the current collector member The terminal member is provided with a through-hole that is fixed by caulking the end portion of the through-terminal member and the terminal member being caulked. An escape portion is formed around the circumference .

In the present invention according to claim 1, since the through terminal member is fixed to the current collecting member or the terminal member by friction (friction welding), the through terminal member can be formed in an integrated state, and the number of parts is reduced. The influence on the contact failure can be eliminated. As a result, it is possible to improve reliability by improving electrical performance and mechanical performance at the electrode terminal.
And since there is no mechanical fixation between the current collecting member and the penetrating terminal member, and the fixing work between the current collecting member and the penetrating terminal member becomes unnecessary inside the battery outer member, Without considering the work space, the position of the penetrating terminal member, that is, the position of the terminal member can be arbitrarily set.
In addition, when the end portion of the through terminal member is caulked and fixed to the through hole of the terminal member, the material of the through terminal member bites into the escape portion of the through hole, and the bonding strength in the circumferential direction is improved and the play in the circumferential direction is not stable. The contact state can be kept good.

A nonaqueous electrolyte secondary battery according to a second aspect of the present invention is the nonaqueous electrolyte secondary battery according to the first aspect, wherein the penetration terminal member is melted by frictional heat generated by pressing while rotating. It is fixed by wearing. Moreover, the nonaqueous electrolyte secondary battery of the present invention according to claim 3 is the nonaqueous electrolyte secondary battery according to claim 1, wherein the through-terminal member causes the joint portion to flow plastically between the joint portions. It is characterized by being integrated and fixed. For this reason, a penetration terminal part can be formed in an integrated state by friction welding or friction stir welding.

A nonaqueous electrolyte secondary battery according to a fourth aspect of the present invention is the nonaqueous electrolyte secondary battery according to any one of the first to third aspects, wherein the through-terminal member and the battery exterior member are provided. A packing is interposed between the inner side of the sealing terminal, the packing is fitted to the base end portion of the penetrating terminal member and maintains sealing performance, and the penetrating terminal member is in close contact with the seal packing. It consists of the holding packing which has the rigidity which receives the force which acts between the said battery exterior members.

In the present invention according to claim 4 , the base end side of the penetrating terminal portion is sealed by the seal packing, and the displacement force acting between the current collecting member and the battery exterior member is received by the holding packing. It is possible to achieve both sealing performance and rigidity.

  As the holding packing having rigidity, for example, polyphenylene sulfide (PPS) resin having high rigidity is preferably used. Further, as the seal packing for maintaining the sealing performance, for example, tetrafluoroethylene / purple oloalkyl vinyl ether copolymer (PFA) resin or polypropylene (PP) resin is preferably used.

The nonaqueous electrolyte secondary battery of the present invention according to claim 5 is the nonaqueous electrolyte secondary battery according to claim 4 , wherein the holding member is disposed between the terminal member and the outside of the battery exterior member. An upper packing made of the same material as the packing is interposed.

In this invention which concerns on Claim 5 , the force of the displacement direction which acts relatively between a terminal member and a battery exterior member is received by the upper packing which has rigidity.

  The non-aqueous electrolyte secondary battery of the present invention can reduce the number of parts of a member for taking out current, improve electrical performance and mechanical performance at the electrode terminal, and increase reliability. become.

  FIG. 1 is an exploded perspective view showing the overall structure of a nonaqueous electrolyte secondary battery according to an embodiment of the present invention, FIG. 2 is a partially broken side view showing the structure inside the battery case, and FIG. 4 is a front view of the positive electrode side, FIG. 5 is a front view of the negative electrode side, FIG. 6 is an exploded view of terminal components on the positive electrode side, and FIG. FIG. 8 shows a detailed situation of the positive electrode terminal member, FIG. 9 shows a detailed situation of the negative electrode terminal member, FIG. 10 shows an appearance of the electrode group (stack element), and FIG. FIG. 12 shows the production status of the electrode group, FIG. 13 shows a plane representing the connection status of the cells, and FIG. 14 shows the joining status of the connection bar.

The overall structure of the nonaqueous electrolyte secondary battery will be described with reference to FIGS.
As shown in FIG. 1, a non-aqueous electrolyte secondary battery (lithium ion secondary battery) 1 is configured such that an electrode group 3 is accommodated inside a battery case 2. A lid member 4 (battery exterior member) of the battery case 2 is connected to the upper surface portion of the electrode group 3, and the positive electrode terminal member 5 and the negative electrode terminal member 6 are arranged on the upper surface of the lid member 4 so as to be exposed. The positive electrode portion 3a of the electrode group 3 is fixed to a current collector 7 as a positive current collector, and the negative electrode portion 3b of the electrode group 3 is fixed to a current collector 8 as a negative current collector. The current collector 7 is electrically connected to the positive electrode terminal member 5 with the lid member 4 interposed therebetween, and the current collector 8 is electrically connected to the negative electrode terminal member 6 with the lid member 4 interposed therebetween.

  Although details will be described later, the positive electrode portion 3a of the electrode group 3 is an aluminum foil aggregate (bundle), and the current collector 7 is made of aluminum. The negative electrode portion 3b of the electrode group 3 is a copper foil aggregate (bundle), and the current collector 8 is made of copper.

The state of connection between the lid member 4 and the current collector 7 and current collector 8 (structure of the electrode terminal portion) will be described.
As shown in FIGS. 2 to 5, the lid member 4 has a rectangular plate shape, and a current collector 7 and a current collector 8 are disposed at the end in the longitudinal direction on the inner side (lower side in FIG. 2) of the lid member 4. It is connected. A positive electrode terminal member 5 and a negative electrode terminal member 6 that are conductively connected to the current collector 7 and the current collector 8 are provided on the end side in the longitudinal direction on the outer side (upper side in FIG. 2) of the lid member 4. .

  Since the current collector 7 and the current collector 8 are different in material and have the same structure, the following description will be given by taking the current collector 7 on the positive electrode side as an example, and description of the current collector 8 on the negative electrode side will be omitted. It is.

  The current collector 7 includes an upper surface plate 11 that is in contact with the inner surface of the lid member 4 and a long joining plate 12 that extends downward from the end of the upper surface plate 11. The current collector 7 is formed in an inverted L shape in a side view by an upper surface plate 11 and a long joining plate 12, and is extended outward in the longitudinal direction (vertical direction) at both edges of the long joining plate 12. A connecting plate piece 13 is formed, and the long joining plate 12 has a U-shaped cross section. Two rows of positive electrode portions 3a of the electrode group 3 are joined to the connection plate piece 13 of the long joining plate 12, respectively.

  As shown in FIG. 6, an aluminum penetrating terminal member 15 is provided on the upper surface plate 11 of the current collector 7, and the penetrating terminal member 15 has a cylindrical shape and is welded to the upper surface plate 11.

  As shown in FIG. 7, in the welding of the penetrating terminal member 15, the joint portion is fixed to the upper surface plate 11 of the current collector 7 by friction. That is, the cylindrical penetrating terminal member 15 is pressed against the upper surface plate 11 while rotating, and the penetrating terminal member 15 is fused and fixed to the upper surface plate 11 by the generated frictional heat.

  As shown in FIGS. 2, 3, 4, and 6, the upper portion of the penetrating terminal member 15 is arranged to penetrate the lid member 4, and the penetrating terminal member 15 penetrates (fits) into the positive terminal member 5. A through hole 16 is formed. The upper end portion of the through terminal member 15 is caulked and fixed to the through hole 16. Since the penetrating terminal member 15 has a cylindrical shape, the material can be uniformly deformed in the circumferential direction during caulking and fixing.

  In the present embodiment example, since the through terminal member 15 is fixed to the current collector 7 by friction (friction welding), the through terminal portion can be formed in an integrated state, the number of parts is reduced, and contact failure is prevented. The influence can be eliminated. As a result, it is possible to improve reliability by improving electrical performance and mechanical performance at the electrode terminal.

  In the above embodiment, the example in which the through terminal member 15 is formed integrally with the upper surface plate 11 of the current collector 7 has been described. However, the through terminal member 15 may be formed integrally with the lower surface of the positive electrode terminal member 5. It is.

  On the other hand, as shown in FIG. 6, a lower packing 17 as a packing is interposed between the upper surface plate 11 of the current collector 7 and the lid member 4. The lower packing 17 is fitted to the base end portion of the penetrating terminal member 15 so as to maintain a sealing property, and receives a force acting between the penetrating terminal member 15 and the lid member 4 in close contact with the seal packing 47. The holding packing 48 has rigidity.

  The seal packing 47 includes a cylindrical portion 47 a that is fitted to the through terminal member 15 and a flange portion 47 b that is in close contact with the upper surface of the upper surface plate 11 of the current collector 7. The holding packing 48 has a fitting hole 48 a into which the flange portion 47 b of the seal packing 47 is fitted. The flange portion 47 b of the sealing packing 47 is fitted into the fitting hole 48 a of the holding packing 48, thereby The lower packing 17 is formed by integrating the holding packing 48.

  The fitting hole 48a of the holding packing 48 is formed smaller than the flange portion 47b of the seal packing 47, and the flange portion 47b of the sealing packing 47 is overlapped with the fitting hole 48a of the holding packing 48 so as to be integrated. It is also possible to constitute the packing 17. Further, the seal packing 47 may be configured only by the cylindrical portion 47 a, and a fitting hole 48 a into which the outer periphery of the cylindrical portion 47 a is fitted can be formed in the holding packing 48.

  An upper packing 18 is interposed between the positive electrode terminal member 5 and the lid member 4, and a hole 18 a through which the penetrating terminal member 15 passes is formed in the upper packing 18. The material of the upper packing 18 is the same material as the holding packing 48 of the lower packing 17.

  The holding packing 48 and the upper packing 18 of the lower packing 17 are in close contact with the lid member 4 and have resistance to the electrolyte, and a highly rigid polyphenylene sulfide (PPS) resin is used. Further, the seal packing 47 of the lower packing 17 is in close contact with the lid member 4 and has resistance to the electrolyte, and a flexible tetrafluoroethylene / purple oloalkyl vinyl ether copolymer (PFA) resin is used.

  Note that polypropylene (PP) resin may be used as the holding packing 48 and the upper packing 18 of the lower packing 17.

  Since the upper end portion of the penetrating terminal member 15 is caulked and fixed to the through hole 16 of the positive electrode terminal member 5, relative displacement between the lid member 4 and the current collector 7 (penetrating terminal member 15) during caulking is fixed. Power works. Even when a relative displacement force acts between the lid member 4 and the current collector 7 (through terminal member 15) during the caulking and fixing, the sealing performance is ensured by the flexible seal packing 47. That is, since the seal packing 47 excellent in compressibility is interposed, a gap or the like does not occur between the penetrating terminal member 15 and the lid member 4 due to the displacement force that is applied during caulking. Further, the force acting on the lid member 4 during the caulking and fixing can be received by the rigid holding packing 48 and the upper packing 18. Furthermore, the head of the penetrating terminal member 15 is crimped to increase the diameter and press in the vertical direction, so that the sealing performance is improved.

  For this reason, the mechanical strength and the sealing performance can be made compatible at the electrode terminal portion, and the reliability of the battery is not lowered. In particular, it is possible to maintain reliability when the battery is enlarged.

  The positive electrode terminal member 5 and the negative electrode terminal member 6 will be described with reference to FIGS. 6, 8, and 9. Although FIG. 6 shows the positive electrode terminal member 5 side, the structure of the negative electrode terminal member 6 side is also the same, and therefore the negative electrode terminal member 6 will be described using the members shown in FIG. It is.

The positive electrode terminal member 5 will be described.
8A shows a plan view of the positive electrode terminal member 5, FIG. 8B shows a side view of the positive electrode terminal member 5, and FIG. 8C shows details of the through holes.

  As shown in FIGS. 8A and 8B, the positive electrode terminal member 5 has a contact plate portion 21 that is in close contact with the upper packing 18 on the upper surface of the lid member 4. A through hole 16 through which the member 15 passes is formed. A connection plate portion 22 is formed continuously with the contact plate portion 21, and the connection plate portion 22 is disposed between the upper packing 18 and a gap. A pair of terminal claws 23 a and 23 b is formed on the connection plate portion 22, and the pair of terminal claws 23 a and 23 b are arranged in parallel in a direction (vertical direction in FIG. 8) orthogonal to the longitudinal direction of the lid member 4. .

The negative electrode terminal member 6 will be described.
9A shows a plan view of the negative electrode terminal member 6, FIG. 9B shows a side view of the negative electrode terminal member 6, and FIG. 9C shows details of the through hole.

  As shown in FIGS. 9A and 9B, the negative electrode terminal member 6 has a contact plate portion 27 that is in close contact with the upper packing 18 on the upper surface of the lid member 4, and the contact plate portion 27 includes a through terminal. A through hole 26 through which the member 15 passes is formed. A connection plate portion 28 is formed continuously with the close contact plate portion 27, and the connection plate portion 28 is disposed between the upper packing 18 and a gap. A pair of terminal claws 29 a and 29 b are formed on the connection plate portion 28, and the pair of terminal claws 29 a and 29 b are juxtaposed in a direction along the longitudinal direction of the lid member 4 (left and right direction in FIG. 9).

  In other words, the parallel arrangement direction (longitudinal direction) of the pair of terminal claws 23 a and 23 b of the connection plate portion 22 and the parallel arrangement direction (longitudinal direction) of the pair of terminal claws 29 a and 29 b of the connection plate portion 28 are the lid member 4. In the plane (in the plane of the terminal member).

  As shown in FIG. 8C, relief portions 24 are formed at four locations in the circumferential direction on the inner periphery of the through hole 16 of the contact plate portion 21 of the positive electrode terminal member 5. As shown in FIG. 9C, relief portions 30 are formed at four locations in the circumferential direction on the inner periphery of the through hole 26 of the contact plate portion 27 of the negative electrode terminal member 6. Therefore, when the upper end portion of the through terminal member 15 is caulked and fixed to the through hole 16 of the positive electrode terminal member 5 and the through hole 26 of the negative electrode terminal member 6, the material of the through terminal member 15 bites into the escape portion 24 and the escape portion 30. Further, the joining strength in the circumferential direction of the through-terminal member 15 is improved and the play in the circumferential direction is eliminated.

  Therefore, the contact state between the current collector 7 and the current collector 8 and the positive electrode terminal member 5 and the negative electrode terminal member 6 through the penetrating terminal member 15 can be kept good, and the electrical performance and mechanical performance are improved. Can be made.

The electrode group 3 is demonstrated based on FIG. 10, FIG.
As shown in the figure, in the electrode group 3, a large number of aluminum foils 55 on the positive electrode side and copper foils 56 on the negative electrode side are alternately stacked, and the aluminum foil 55 and the copper foil 56 hold an active material and are partitioned by a separator. ing. The end portions of the aluminum foil 55 (active material non-holding portions) and the end portions of the copper foil 56 (active material non-holding portions) are overlapped with each other on the opposite ends, and the end portions of the aluminum foil 55 are bundled together. A positive electrode portion 3a is formed, and ends of the copper foil 56 are bundled to form a negative electrode portion 3b. The positive electrode part 3a and the negative electrode part 3b of the electrode group 3 are in a state of being provided in two rows. That is, the stack is divided into two per one electrode group 3 (one cell).

The production status of the electrode group will be described with reference to FIG. FIG. 12 shows one stack.
As shown in FIG. 12 (a), the end of the aluminum foil 55 where the active material is not held is laminated on one side, and the end of the copper foil 56 where the active material is not held is on the other side. Are stacked. As shown in FIG. 12 (b), the end portions of the aluminum foil 55 on one side and the laminated portion of the copper foil 56 on the other side are bundled (foiled), bent and cut to make the lengths uniform. As shown in FIG. 12 (c), the end portions are temporarily fixed in length and fixed and joined with a not-shown fastener or the like to form a positive electrode portion 3a and a negative electrode portion 3b in a predetermined state.

  The electrode group 3 has a thickness in the foil stacking direction, and when the end portion is made of foil, the foils located on both sides are shorter than the foil located in the center in the thickness direction. For this reason, the length of the end portion of the aluminum foil 55 and the end portion of the copper foil 56 (active material non-holding portion) is sufficiently secured, and the foil is tempered so that bending and cutting are not impossible.

  In the present embodiment example, the stack is divided into two, so that the number of current collecting points of the electrodes to be joined together with the foil is increased, and the portion held by the current collector 7 (8) Therefore, the resistance of the current collector can be reduced and the mechanical strength can be increased.

Based on FIGS. 13 and 14, a state in which a plurality of nonaqueous electrolyte secondary batteries 1 shown in FIG. 1 are arranged and connected, that is, a state in which a plurality of cells are arranged and connected will be described.
As shown in FIG. 13, adjacent nonaqueous electrolyte secondary batteries 1 are alternately arranged in a state where the positive electrode terminal members 5 and the negative electrode terminal members 6 are adjacent to each other. The adjacent positive electrode terminal member 5 and negative electrode terminal member 6 are connected by a connection bar 31 to form a battery unit in which a plurality of nonaqueous electrolyte secondary batteries 1 are connected in series. For this reason, the connection bar 31 is a member having a length in a direction orthogonal to the length direction of the lid member 4 of the nonaqueous electrolyte secondary battery 1.

The connection bar 31 will be described.
One end of the connection bar 31 is provided with a positive electrode connection portion 32 connected to the positive electrode terminal member 5, and the other end of the connection bar 31 is provided with a negative electrode connection portion 33 connected to the negative electrode terminal member 6.

  In the positive electrode connection portion 32, a long hole 34 extending in the longitudinal direction of the connection bar 31, that is, a long hole 34 extending in a direction orthogonal to the longitudinal direction of the lid member 4 is formed. A pair of connecting claws 35a and 35b are provided along the longitudinal direction at the long side edge of the long hole 34, and a gap s is formed between the end of the long hole 34 and the pair of connecting claws 35a and 35b. Yes. The connecting claws 35 a and 35 b are formed so that the longitudinal direction (parallel direction) corresponds to the terminal claws 23 a and 23 b of the positive electrode terminal member 5.

  The negative electrode connecting portion 33 is formed with a long hole 36 extending in the direction perpendicular to the longitudinal direction of the connection bar 31, that is, a long hole 36 extending in the longitudinal direction of the lid member 4. A pair of connecting claws 37a and 37b are provided along the longitudinal direction at the edge of the long hole 36, and a gap s is formed between the end of the long hole 36 and the pair of connecting claws 37a and 37b. The connecting claws 37 a and 37 b are formed so that the longitudinal direction (parallel arrangement direction) corresponds to the terminal claws 29 a and 29 b of the negative electrode terminal member 6.

  As shown in FIG. 14A, the long hole 34 of the positive electrode connecting portion 32 of the connection bar 31 is fitted into the terminal claws 23a, 23b of the positive electrode terminal member 5, and the long hole 36 of the negative electrode connecting portion 33 is negative electrode terminal member. 6 terminal claws 29a and 29b. The longitudinal direction (parallel direction) of the terminal claws 23a, 23b of the positive electrode terminal member 5 and the terminal claws 29a, 29b of the negative electrode terminal member 6 intersect each other in a direction perpendicular to each other, and the long holes 34 and 36 of the connection bar 31 Since the longitudinal direction is along the longitudinal direction of the terminal claws 23a, 23b and the terminal claws 29a, 29b, the connection bar 31 is allowed to connect only between the positive terminal member 5 and the negative terminal member 6.

  That is, the connection bar 31 only allows connection between the positive electrode and the negative electrode, and even when the positive electrodes and the negative electrodes of the non-aqueous electrolyte secondary battery 1 are arranged, the connection bar 31 has a connection bar between adjacent terminal members. Since 31 cannot be attached, the polarity of the positive electrode and the negative electrode is not wrongly connected. For this reason, the use of the connection bar 31 can eliminate problems such as work mistakes and short circuits.

  The positive electrode connection portion 32 and the negative electrode connection portion 33 of the connection bar 31 are fitted into the positive electrode terminal member 5 and the negative electrode terminal member 6, the connection claws 35a and 35b and the terminal claws 23a and 23b are abutted, and the connection claws 37a and 37b and the terminal claws 29a and 29b are brought together. As shown in FIG. 14 (b), the connection claws 35a and 35b and the upper portions of the terminal claws 23a and 23b, and the connection claws 37a and 37b and the upper portions of the terminal claws 29a and 29b are welded (TIG welding or the like), respectively. Are joined together. Thereby, the positive electrode terminal member 5 and the negative electrode terminal member 6 are bonded and fixed.

  By using the connection bar 31, it is possible to connect between the polarities of the nonaqueous electrolyte secondary battery 1 without using fastening members such as bolts and nuts and in a state where the polarity is not mistaken, Joining is simple and reliable, the number of parts for connection and the number of work steps can be reduced, and the connection space can be reduced.

  A gap s is formed between the end of the long hole 34 of the connection bar 31 and the pair of connection claws 35a and 35b, and a gap s is formed between the end of the long hole 36 and the pair of connection claws 37a and 37b. Therefore, even if the non-aqueous electrolyte secondary battery 1 is shifted and disposed, it is absorbed within the gap s. Since the gaps s are provided at the ends of the elongated hole 34 and the elongated hole 36 that are orthogonal to each other, the relative displacement in an arbitrary direction within the horizontal plane of the nonaqueous electrolyte secondary battery 1 can be absorbed. it can.

  A pair of connection claws are provided on the positive electrode connection portion 32 and the negative electrode connection portion 33 of the connection bar 31, respectively, so that the connection claws and the terminal claws of the terminal member are opposed to each other. It is also possible to provide.

  Based on FIG. 15, another embodiment of the joining state of the through terminal member 15 and the current collector 7 will be described. The through terminal member 15 of the present embodiment is integrally provided on the upper surface plate 11 of the current collector 7 by friction stir welding.

  As shown in FIG. 15 (a), a flange portion 61 is formed at the lower end portion of the penetrating terminal member 15, and a disk-shaped concave portion 62 is formed at the attachment portion of the penetrating terminal member 15 of the upper surface plate 11 of the current collector 7. Is formed. By fitting the flange portion 61 of the penetrating terminal member 15 into the concave portion 62 of the upper surface plate 11, the upper surface of the upper surface plate 11 and the upper surface of the flange portion 61 are flush with each other, and the penetrating terminal member 15 becomes the current collector 7. Retained.

  In this state, the rotating tool 63 made of steel is pressed against the fitting portion (joint portion between the flange portion 61 and the recess 62) on the outer peripheral portion of the flange portion 61 so as to penetrate the joint portion. The rotary tool 63 is rotated and moved along the joint, frictional heat is generated at the joint, the joint is softened, and the joints are plastically flowed to integrate the flange 61 and the recess 62. That is, the through-terminal member 15 is fixed to the upper surface plate 11 of the current collector 7 by friction stir welding, and the through-terminal member 15 is integrally provided on the upper surface plate 11.

  For this reason, since the penetration terminal member 15 is fixed to the current collector 7 by plastic flow between the joint portions, the penetration terminal member 15 can be formed in an integrated state, the number of parts is reduced, and the influence on contact failure is affected. Can be eliminated. As a result, it is possible to improve reliability by improving electrical performance and mechanical performance at the electrode terminal.

  In the configuration of the present invention described above, the long joining plate 12 connected to the electrode group 3 and the through terminal member 15 are formed as one member, and the upper plate is formed by caulking the separate through terminal member. Compared with the structure fixed to 11, electrical performance and mechanical performance can be improved. In particular, since the current collector 7 is made of aluminum, problems such as insufficient strength and increased contact resistance due to caulking of aluminum can be eliminated. Furthermore, the number of parts can be reduced. Therefore, the electrical reliability and the mechanical reliability are greatly improved, and the parts management considering the surface oxidation becomes unnecessary, and the parts management becomes easy.

  Since the through-terminal members 15 of the current collector 7 and the current collector 8 are fixed integrally with the upper surface plate 11, the caulking work of the through-terminal member 15 on the lower surface side of the upper surface plate 11 becomes unnecessary, and the upper surface plate It is not necessary to secure a work space on the lower surface side of 11. For this reason, even if the long joining plate 12 extending downward from the end portion of the upper surface plate 11 exists, the penetrating terminal member 15 is disposed closer to the end portion of the upper surface plate 11 (closer to the end portion of the lid member 4). The electrical path length through the penetrating terminal member 15 to the terminal claws 23a, 23b (29a, 29b) of the positive electrode terminal member 5 (negative electrode terminal member 6) can be shortened, and the circuit resistance can be reduced. It becomes possible to make it smaller. Moreover, the positive electrode terminal member 5 (negative electrode terminal member 6) and the upper surface board 11 can be reduced in size, and the usage-amount of the material of the member which comprises a connection part can be reduced.

  The non-aqueous electrolyte secondary battery 1 of the present embodiment described above is reliable by reducing the number of parts of a member for taking out current and improving electrical performance and mechanical performance at the electrode terminal. Can be increased.

  The present invention can be used in the industrial field of non-aqueous electrolyte secondary batteries.

It is a disassembled perspective view showing the whole structure of the nonaqueous electrolyte secondary battery concerning the example of one embodiment of the present invention. It is a partially broken side view showing the structure inside a battery case. It is the III-III arrow directional view in FIG. It is a front view on the positive electrode side. It is a front view on the negative electrode side. It is an exploded side view of the terminal component on the positive electrode side. It is an exploded perspective view concerning one example of an embodiment of a penetration terminal member. It is detail drawing of a positive electrode terminal member. It is detail drawing of a negative electrode terminal member. It is an external view of an electrode group (stack element). It is a XX arrow directional view in FIG. It is a manufacturing process figure of an electrode group. It is a top view showing the connection condition of a cell. It is joining state explanatory drawing of a connection bar. It is joining condition explanatory drawing which concerns on the other embodiment example of a penetration terminal member.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Nonaqueous electrolyte secondary battery 2 Battery case 3 Electrode group 4 Lid member 5 Positive electrode terminal member 6 Negative electrode terminal member 7 Current collector (positive electrode side)
8 Current collector (negative electrode side)
DESCRIPTION OF SYMBOLS 11 Upper surface board 12 Long joining board 13 Connection board piece 15 Through-terminal member 16, 26 Through-hole 17 Lower packing 18 Upper packing 21, 27 Contact board part 22, 28 Connection board part 23, 29 Terminal claw 24, 30 Escape part 31 Connection bar 32 Positive electrode connection 33 Negative electrode connection 34 Long hole (positive electrode side)
35, 37 Connection claw 36 Long hole (negative electrode side)
47 Seal packing 48 Holding packing 50 Welding part 61 Flange part 62 Recessed part 63 Rotating tool

Claims (5)

A current collecting member provided on the inside of the battery exterior member and conducting to the electrode;
A terminal member provided outside the battery exterior member;
A penetrating terminal member provided through the battery exterior member and conducting the current collecting member and the terminal member;
The feedthrough terminal member protrudes to the battery exterior member side joining site by friction is secured to the current collector member,
The terminal member is provided with a through hole that is penetrated by the through terminal member and fixed by caulking an end portion of the through terminal member.
A nonaqueous electrolyte secondary battery, wherein an escape portion is formed in an inner periphery of the through hole . The nonaqueous electrolyte secondary battery according to claim 1,
The non-aqueous electrolyte secondary battery, wherein the through-terminal member is fixed by fusion due to frictional heat generated by being pressed while rotating. The nonaqueous electrolyte secondary battery according to claim 1,
The non-aqueous electrolyte secondary battery, wherein the through-terminal member is integrally fixed by causing the joints to flow plastically. The nonaqueous electrolyte secondary battery according to any one of claims 1 to 3,
A packing is interposed between the through terminal member and the inside of the battery exterior member,
The packing includes a seal packing that is fitted to a base end portion of the through terminal member to maintain a sealing property, and a rigidity that is in close contact with the seal packing and receives a force acting between the through terminal member and the battery exterior member. A non-aqueous electrolyte secondary battery comprising: a holding packing having : The nonaqueous electrolyte secondary battery according to claim 4,
The non-aqueous electrolyte secondary battery , wherein an upper packing made of the same material as that of the holding packing is interposed between the terminal member and the outside of the battery exterior member .

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