JP2012033395A - Nonaqueous electrolyte secondary battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reliably prevent corotation even when a nonaqueous electrolyte secondary battery is not satisfactory in precision of a terminal member and a corotation prevention member.SOLUTION: A circular projection (corotation prevention member) 1 is projected and provided in the vicinity of each electrode through-hole 11 on the external surface of a cover 4. The electrode through-hole for penetrating a through electrode 11 is bored in an electrode holding member 9, and furthermore a recess 7 is formed on the surface in contact with the cover 4. When the electrode holding member 9 is mounted, the projection 1 is fitted into and engaged with the recess 7 to prevent the rotation around the through electrode 11 of the electrode holding member 9. The recess 7 is formed into an oval shape having the longitudinal direction of the cover 4 as a long diameter direction and even when a position of the projection 1 is dislocated, the projection 1 is reliably fitted to the recess 7.

Description

  The present invention relates to a non-aqueous electrolyte secondary battery, and more particularly to a non-aqueous electrolyte secondary battery in which a plurality of unit batteries can be integrated to constitute a battery module.

  This type of non-aqueous electrolyte secondary battery is a secondary battery that is mounted as a power source on mobile bodies such as automobiles, motorcycles, railways, construction machinery, bicycles, and electric welfare equipment, uninterruptible power supplies, wind power generation, solar power It is applied to batteries that require high reliability, such as stationary batteries installed in power generation, distributed power storage systems, and the like.

  The secondary battery described in Patent Document 1 has the following configuration with reference to FIG. A lead battery terminal 1 is provided for connection between secondary batteries and power output from the secondary battery, and a screw is formed on the terminal member 2 of the lead battery terminal 1. In order to prevent the lead battery terminal 1 from rotating around when the nut is screwed onto the lead battery terminal 1, the secondary battery of Patent Document 1 is provided with a rotation prevention mechanism. That is, the lead bush 4 is fitted into the terminal member 2, and the fitting portion 41 of the lead bush 4 is fitted into the resin cover 6. Referring to paragraph 0029 of Patent Document 1, by engaging the protrusion below the fitting portion 41 with the resin cover 6, even if a tightening torque is applied to the terminal member 2, the protrusion 1 bites into the lead battery terminal 1. It is set as the structure which can prevent that the whole of turning.

JP 10-116602 A

  However, in the secondary battery of Patent Document 1, when the positional accuracy and the like of the fitting portion 41 serving as a rotation prevention mechanism for the terminal member 2 and the pole 5 to which the fitting portion 41 is attached are insufficient, lead There is a possibility that the effect of preventing the battery terminal 1 from rotating is not obtained.

  The non-aqueous electrolyte secondary battery according to the invention of claim 1 includes a container having an opening, a lid that seals the opening and provided with an external electrode, and is accommodated in the container, and the external electrode A power generator that charges and discharges electric power to and from an external load, an internal connection member and an external connection member that electrically connect the power generator and the external electrode, the external connection member, and the lid An electrode holding member that holds the base of the external electrode so that the tip of the external electrode penetrates the external connection member, and from the inside of the lid at a predetermined distance from the external electrode Further, the electrode holding member and the external connection member penetrate through and are fixed to the lid, one end inside the container is electrically connected to the internal connection member, and the other end outside the container is the external Electrically connected to the external electrode by a connecting member Connected through electrodes, and a rotation prevention mechanism that prevents a rotational moment acting on the electrode holding member around the through electrode, the rotation prevention mechanism including the lid and the electrode holding member. A protrusion provided on one of the protrusions and a recess provided on the other of the lid and the electrode holding member, the protrusion engaging with play in a direction perpendicular to the rotational moment. Features.

  According to the present invention, the electrode holding member can be rotated by the rotational moment acting on the external electrode without providing the position of the protrusion and the position of the concave portion that engages the protrusion and prevents the rotation with high positional accuracy. It can be surely prevented.

The perspective view which shows the battery module using 1st Embodiment of the nonaqueous electrolyte secondary battery by this invention. The disassembled perspective view of the nonaqueous electrolyte secondary battery of 1st Embodiment. The perspective view of the container and lid | cover of the nonaqueous electrolyte secondary battery of 1st Embodiment. The expanded perspective sectional view of the external electrode part of the nonaqueous electrolyte secondary battery of a 1st embodiment. The perspective view which shows the electrode holding member of 1st Embodiment. FIG. The perspective view of the container and cover in 2nd Embodiment of the nonaqueous electrolyte secondary battery by this invention. The perspective view which shows the electrode holding member of 2nd Embodiment. IX arrow line view of FIG.

  An embodiment in which the present invention is applied to a prismatic nonaqueous electrolyte secondary battery will be described with reference to the drawings.

[First Embodiment]
-Battery module-
As shown in FIG. 1, for example, twelve non-aqueous electrolyte secondary batteries 20 are housed in a module case 22 and are used so as to constitute a battery module 100 connected in series. The twelve batteries are protected by the module case 22 and are configured to withstand external forces such as vibration and impact.

  In the module case 22, the directions of the nonaqueous electrolyte secondary batteries 20 are alternately arranged so that the positive electrode external electrode bolts 12P and the negative electrode external electrode bolts 12N of the adjacent nonaqueous electrolyte secondary batteries 20 are adjacent to each other. It is arranged in reverse. Then, the bus bar 19 is bridged between the external electrode bolts 12P and 12N having opposite polarities to the adjacent nonaqueous electrolyte secondary battery 20, and the adjacent nonaqueous electrolyte secondary batteries 20 are electrically connected to each other. . The bus bar 19 is screwed and fixed to the external electrode bolt 12 with a nut 12T. In this way, the battery module 100 is configured.

  In FIG. 1, the code | symbol 21 shows the duct which stores the gas discharged | emitted from the pressure release valve (illustration omitted) provided in the nonaqueous electrolyte secondary battery 20. FIG. In the unlikely event of a thermal runaway or a pressure increase within the battery, the duct 21 will be filled with gas.

-Non-aqueous electrolyte secondary battery-
As shown in FIG. 2, the non-aqueous electrolyte secondary battery 20 includes a flat rectangular parallelepiped metal rectangular container 5 having an elongated rectangular opening, and a power generator 15 inserted into the rectangular container 5. . A metal lid 4 is fixed to the opening of the rectangular container 5 by laser beam welding, and the rectangular container 5 is sealed. After the lid 4 is welded to the rectangular container 5, the electrolyte is injected into the rectangular container 5 from the pressure release valve attachment hole 3, and then the pressure release valve is attached to the pressure release valve attachment hole 3.

  The lid 4 is a strip-shaped rectangle corresponding to the opening. An internal electrode 14 extending in the internal direction of the rectangular container 5 is fixed to the lid 4, and a power generator 15 is welded to the internal electrode 14 via a pressing plate 17. The welding is ultrasonic welding or laser beam welding, and the welded portion is indicated by reference numeral 18 in the figure. As will be described later, a through electrode 11 connected to the external electrode 12 is provided at the other end of the internal electrode 14. As shown in FIG. 2, the through electrode 11 protrudes from the battery through the lid 4.

  The power generator 15 is, for example, a flat wound electrode group obtained by winding a positive foil and a negative foil in a state insulated by a separator, and an internal current collector plate is provided at both ends of the flat wound electrode group. The electrode 14 is welded. Electric power is charged and discharged by the power generator 15.

  The through electrode 11 is fixed to the lid 4 by caulking, and together with the through electrode 11, a connection bar 10 that functions as a terminal member, an internal electrode 14, and an electrode holding member 9 that functions as a rotation prevention mechanism are fixed to the lid 4. Yes. An external electrode bolt 12 is attached to the electrode holding member 9 through the connection bar 10. An insulating member 13 is inserted between the internal electrode 14 and the inner surface of the rectangular container 5.

FIG. 3 is a perspective view in which the lid 4 and the container 5 are integrated, and FIG. 4 is a cross-sectional view illustrating the structure around the through electrode 11 and the external electrode bolt 12.
As shown in FIG. 3, the lid 4 is provided with an electrode through hole 2 through which the positive and negative through electrodes 11 are inserted, and the through electrode 11 is formed inside the lid 4 as shown in FIG. 14 is fixed by caulking. A gasket 16 is attached to the electrode through hole 2 from the inside of the lid 4, and the through electrode 11 passes through the electrode through hole 2 while being sealed by the gasket 16. An electrode holding member 9 is fitted to the through electrode 11 on the outside of the lid 4, and a connection bar 10 is fitted to the outside thereof. The through electrode 11 is caulked on the outside of the connection bar 10, whereby the connection bar 10 and the electrode holding member 9 are fixed on the outside of the lid 4.

  As shown in FIG. 3, the electrode through holes 2 are arranged on both sides of the pressure release valve mounting hole 3 and are separated in the longitudinal direction of the lid 4. On the outer surface of the lid 4, a circular protrusion 1 protrudes in the vicinity of each electrode through hole 2. The protrusion 1 and the electrode through-hole 2 are disposed at a predetermined distance in the longitudinal direction of the lid 4. The protrusions 1 are provided at substantially both ends of the lid 4 and function as a rotation prevention mechanism described later.

  5 and 6 are perspective views of the electrode holding member 9. The electrode holding member 9 is provided with an electrode through hole 8 for penetrating the through electrode 11, and a recess 7 is formed on the surface in contact with the lid 4. In the electrode holding member 9, the portion where the concave portion 7 is formed is a thick portion 9T which is thicker than the portion where the electrode through hole 8 is formed (referred to as a thin portion 9t). When the electrode holding member 9 is attached, the protrusion 1 is fitted and engaged with the recess 7, and rotation of the electrode holding member 9 around the through electrode 11 is prevented.

  The electrode holding member 9 functions as a “reaction force member” for supporting the rotational torque when the nut 12T is tightened to the external electrode bolt 12, and the protrusion 1 and the recess 7 of the electrode holding member 9 cooperate with each other, It functions as a “rotation prevention mechanism” that prevents the external electrode bolt 12 from rotating.

  The recess 7 has an oval shape in which the longitudinal direction of the lid 4 is the major axis direction, and the minor axis thereof is substantially equal to the diameter of the protrusion 1. Thereby, even when the position of the protrusion 1 is shifted, the protrusion 1 is securely and tightly fitted into the recess 7. Therefore, the tolerance regarding the position of the protrusion 1, in particular, the distance from the electrode through hole 8 can be increased.

  That is, the recess 7 is formed so that the protrusion 1 engages with play in a direction orthogonal to the rotational moment acting on the external electrode bolt 12. As long as such a function can be achieved, the shape of the protrusion 1 and the recess 7 of the rotation prevention mechanism is not limited to the embodiment.

  The electrode holding member 9 is made of an insulating material, but can be made of a brittle material such as ceramics or glass. In this case, it is preferable that the dimension of the concave portion 7 in the direction perpendicular to the longitudinal direction is slightly larger than the diameter of the protrusion 1 provided on the lid 4 to prevent interference of the members. The electrode holding member 9 may be formed of a ductile material such as an insulating resin material. In this case, the dimension in the width direction of the recess 7 is slightly smaller than the diameter of the protrusion 1 and is fitted. May be an interference fit.

  As shown in FIG. 4, the connection bar 10 is provided with through holes 102 and 104 through which the through electrode 11 and the external electrode bolt 12 pass, respectively. The through electrode 11 is caulked so as to spread around the through hole 102, and the electrode holding member 9 and the connection bar 10 are fastened and fixed.

  The external electrode bolt 12 includes a shaft portion 12B that penetrates the through hole 104, a contact portion 12S that is continuous with the shaft portion 12B and has a larger diameter than the shaft portion 12B, and a contact portion that is continuous with the contact portion 12S. A head 12H having a diameter larger than 12S is provided. A screw for screwing the nut 12T is formed on the outer periphery of the shaft portion 12B. The head 12H is a polygon such as a square, a rectangle, or a hexagon, and is prevented from rotating by restraining the opposite side.

  As shown in FIG. 5, the thick portion 9T of the electrode holding member 9 is formed with a T-shaped groove 9R into which the head portion 12H is fitted. The head 12H is inserted into the T-shaped groove 9R from the side of the electrode holding member 9. When the opposite side of the head 12H inserted into the T-shaped groove 9R contacts the T-shaped groove 9R, the rotation of the head 12H is prevented. The electrode holding member 9 is formed with a long hole 9H into which the contact portion 12S can be inserted from the side, and the innermost portion of the long hole 9H has a semicircular shape substantially equal to the diameter of the contact portion 12S. The contact portion 12S contacts the back surface of the connection bar 10 and is prevented from falling off the connection bar 10.

  In the external electrode bolt 12, the head portion 12H is restrained in the T-shaped groove 9R while the contact portion 12S is accommodated in the innermost portion of the long hole 9H. Furthermore, the external electrode bolt 12 is stably held by being prevented from coming off by the contact portion 12S.

  When the nut 12 </ b> T is screwed onto the external electrode bolt 12, a rotational moment about the through-electrode 11 acts on the electrode holding member 9 due to rotational torque about the axis acting on the external electrode bolt 12. At this time, since the protrusion 1 engages with the recess 7 and the rotation of the electrode holding member 9 around the through electrode 11 is prevented, the connection bar 10 is prevented from being rotated. The concave portion 7 is formed in an oval shape in which the longitudinal direction of the lid 4 is the major axis direction. Therefore, without designing so as to provide the position of the protrusion 1 protruding from the lid 4 and the position of the recess 7 recessed in the electrode holding member 9 that engages the protrusion 1 to prevent rotation, It is possible to reliably prevent the electrode holding member 9 and the connection bar 10 from rotating due to the rotational moment acting on the external electrode bolt 12.

  Further, even if the distance between the electrode through-hole 2 of the lid 4 and the projection 1 of the lid 4 is not set with high accuracy, the projection 1 can be securely inserted and engaged with the recess 7 due to poor assembly. Yield reduction is also eliminated.

  The two electrode through-holes 2 and the protrusions 1 are arranged at the approximate center in the width direction of the lid 4 and are arranged in a straight line in the longitudinal direction. With such an arrangement, processing efficiency can be improved and processing errors can be reduced when forming by press molding or cutting.

  As described above, the nonaqueous electrolyte secondary battery according to the present embodiment has various dimensional accuracy of the connection bar 10, positional accuracy of the protrusion 1, fitting accuracy between the lid 4 and the container opening, and various electrode holding members 9. Even when the dimensional accuracy (particularly the accuracy of the position of the concave portion 7) is not good, the electrode holding member 9 can be reliably prevented from rotating.

[Second Embodiment]
A second embodiment in which the present invention is applied to a prismatic nonaqueous electrolyte secondary battery will be described with reference to FIGS. In the figure, the same or corresponding parts as those in the first embodiment are denoted by the same reference numerals, and description thereof is omitted.

  In the second embodiment, two protrusions are engaged with one electrode holding member.

  As shown in FIG. 7, the lid 4 is provided with a pressure release valve mounting hole 3 at substantially the center, and electrode through holes 2 are arranged on both sides of the pressure release valve mounting hole 3. Further, on both sides of each electrode through hole 2, circular protrusions 1a and 1b are provided in the vicinity of each electrode through hole 2, and the protrusion 1a is disposed closer to the end of the lid 4 in the longitudinal direction than the protrusion 1b. Has been. The protrusions 1 a and 1 b and the electrode through hole 2 are arranged in a straight line in the longitudinal direction of the lid 4 at the approximate center in the width direction of the lid 4.

An electrode holding member 9 according to the second embodiment is shown in FIGS.
The electrode holding member 9 is formed with a thick portion 9T similar to that of the first embodiment, and the thin portion 9t is set longer than that of the first embodiment. In the thick portion 9T, a T-shaped groove 9R and a long hole 9H similar to those of the first embodiment are formed, and an oval concave portion 7a similar to the concave portion 7 of the first embodiment is formed. The thick part 9T is disposed at the end of the lid 4, and the protrusion 1a is inserted into the recess 7a.

  An electrode through hole 8 similar to that of the first embodiment is formed in the thin portion 9t of the electrode holding member 9, and the thin portion 9t is further extended than the first embodiment, A second oval recess 7b is formed. The recess 7b is disposed corresponding to the position of the protrusion 1b, and the protrusion 1b is fitted and engaged with the recess 7b.

  According to the nonaqueous electrolytic secondary battery according to the present embodiment, since the two protrusions 1a and 1b of the lid 4 are engaged with the recesses 7a and 7b of the electrode holding member 9, respectively, the electrode holding member 9 is larger. It can withstand rotational torque and can prevent rotation against a large tightening force. That is, the nonaqueous electrolytic secondary battery according to the present embodiment has a large rotational torque that can withstand the effects of the first embodiment. There is an effect.

[Modification]
The above embodiment can be modified as follows.
(1) In the rotation prevention mechanism of the above embodiment, the protrusion 1 is provided on the lid 4 and the recess 7 is provided on the electrode holding member 9. However, the protrusion 1 may be provided on the electrode holding member 9 and the recess 7 may be provided on the lid 4.
(2) In the rotation prevention mechanism of the above embodiment, the protrusion 1 has a play in a direction perpendicular to the rotational moment acting on the electrode holding member 9 around the through electrode 11 due to the rotational torque acting on the external electrode bolt 12. Any combination of structures may be used as long as the recess 7 is formed so as to engage with each other. That is, the shape of the protrusion 1 and the recess 7 is not limited to the embodiment as long as the anti-rotation function can be achieved.

(3) In the second embodiment, the two protrusions are protruded from the lid so that the two protrusions are engaged with each electrode holding member. However, a larger number of protrusions can be engaged. is there.
(4) In the above embodiment, the electrolytic solution is injected from the pressure release valve mounting hole 3, but an electrolytic solution injection hole is provided separately from the pressure release valve mounting hole 3, and the electrolytic solution is injected from the electrolytic solution injection hole. May be.
(5) Although the lid 4 is made of a metal material in the above embodiment, the lid 4 may be made of resin. In this case, the electrode holding member 9 need not be formed of an insulating material.

  The above description is an example, and the present invention is not limited to the above-described embodiments and modifications.

DESCRIPTION OF SYMBOLS 1, 1a, 1b: Protrusion 2: Electrode through-hole 3: Pressure release valve attachment hole 4: Lid 5: Rectangular container 7, 7a, 7b: Recessed part 8: Electrode through-hole 9: Electrode holding member 9H: Long hole 9t: Thin wall Part 9T: Thick part 9RT: Gutter 10: Connection bar 11: Through electrode 11
12: External electrode bolt 12B: Shaft portion 12S: Contact portion 12H: Head portion 12N: Nut 13: Insulating member 14: Internal electrode 15: Power generator 16: Gasket 17: Press plate 18: Welded portion 19: Bus bar 20: Non Water electrolyte secondary battery 21: Duct 22: Module case 100: Battery module 102, 104: Through hole

Claims (8)

A container having an opening;
Sealing the opening and a lid provided with an external electrode;
A power generator that is housed in the container and charges and discharges power to and from an external load via the external electrode;
An internal connection member and an external connection member that electrically connect the power generation body and the external electrode;
An electrode holding member that is sandwiched between the external connection member and the lid and holds a base portion of the external electrode so that a tip of the external electrode penetrates the external connection member;
The lid external electrode penetrates from the inside of the lid external electrode at a position away from the external electrode by a predetermined distance, and further passes through the electrode holding member and the external connection member and is fixed to the lid, and one end in the container is connected to the internal connection A through electrode electrically connected to the member and having the other end outside the container electrically connected to the external electrode by the external connection member;
A rotation prevention mechanism that prevents a rotational moment acting on the electrode holding member around the through electrode; and
The rotation prevention mechanism is
A protrusion protruding from one of the lid and the electrode holding member;
A non-aqueous electrolyte secondary, wherein the secondary electrode has a recess provided on the other side of the lid external electrode and the electrode holding member, and the protrusion engages with play in a direction orthogonal to the rotational moment. battery. The nonaqueous electrolyte secondary battery according to claim 1,
The non-aqueous electrolyte secondary battery, wherein the lid is made of a conductive material, and the electrode holding member is made of an insulating material. The nonaqueous electrolyte secondary battery according to claim 1 or 2,
The non-aqueous electrolyte secondary battery, wherein the internal connection member, the through electrode, the external connection member, the electrode holding member, and the rotation prevention mechanism are provided for a positive electrode and a negative electrode, respectively. The nonaqueous electrolyte secondary battery according to any one of claims 1 to 3,
The lid has a rectangular shape having a through-hole through which the through-electrode penetrates, and the through-hole and the protrusion are arranged in the longitudinal direction of the lid with a predetermined distance therebetween Secondary battery. The nonaqueous electrolyte secondary battery according to any one of claims 1 to 4,
The non-aqueous electrolyte secondary battery according to claim 1, wherein a width of the recess in a direction in which the rotational moment acts is formed such that the protrusion is closely fitted. The nonaqueous electrolyte secondary battery according to any one of claims 1 to 5,
The non-aqueous electrolyte secondary battery, wherein the rotation prevention mechanism has a plurality of protrusions and a plurality of recesses with which the plurality of protrusions engage. The nonaqueous electrolyte secondary battery according to any one of claims 1 to 6,
The non-aqueous electrolyte secondary battery is characterized in that a protrusion constituting the rotation prevention mechanism protrudes from the lid and the recess is provided in the electrode holding member.   A battery module comprising a plurality of nonaqueous electrolyte secondary batteries according to claim 1 connected by a bus bar.

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