JP5862237B2 - Electricity storage element - Google Patents

Description

  The present invention relates to a power storage element that can store electric power and can be discharged as needed, and more particularly, to a power storage element that can increase current extraction efficiency.

  Conventionally, as one of power storage elements such as a non-aqueous electrolyte secondary battery, the power generation device includes a rigid housing and a power generation element housed in the housing, and the power generation is performed by a current collector attached to the inside of the housing. A power storage element in which elements are arranged in a hanging manner is known. In such a storage element, the current collector is mechanically fastened to the housing by a rivet arranged in a state penetrating the housing, and the rivet is also electrically connected to the current collector, The rivet also serves as a terminal for deriving a current from the power storage element to the outside of the housing and introducing a current to the power storage element from the outside of the housing.

  Furthermore, the power storage element includes an electrode terminal for electrical connection with an external device or another battery, and the rivet may fasten the electrode terminal outside the housing of the power storage element.

  For example, as described in Patent Document 1, the electrode terminal is fastened with another terminal by a bolt.

JP 2011-23141 A

  Along with the recent increase in capacity and current of storage elements, the contact area between the storage element and the part that is electrically connected to an external device or other battery is increased to minimize energy loss at the connection part. There is a problem that we want to suppress.

  However, when strongly fastening the electrode terminal and another terminal, it is necessary to strongly tighten the nut. However, if the nut is turned strongly, the head of the bolt may be idle and may not be fastened to a desired strength.

  This invention is made | formed in view of the said subject, and it aims at provision of the electrical storage element which enables rotation prevention of a volt | bolt, without providing another member.

In order to achieve the above object, a power storage element according to the present invention includes a power generation element, a housing that houses the power generation element, and an electrical connection from outside the housing to the power generation element via a current collector. The electrode terminal is provided integrally with the connection portion in a protruding state in a direction intersecting the plane, and a plate-like connection portion having a plane. A housing, a rod-shaped shaft portion disposed in an inserted state in the current collector, a contact portion provided at a distal end portion of the shaft portion and in contact with the current collector, and the connecting portion on the plane And a through-hole through which a bolt for electrically connecting another device and the connection portion is inserted, and the housing has a bulging portion that bulges outward. The shaft portion of the electrode terminal is disposed in a state of being inserted through the bulging portion, and the through hole The A in towards the side of the bulged portion, the head portion and the bulging portion when the head portion of the through hole in the inserted through bolt attempts to rotate is disposed in a position interfering, the through hole The distance between the rotation axis of the bolt inserted through the head and the most protruding portion of the head is greater than the distance between the hole axis of the through hole and the side wall of the bulging portion facing the through hole. Characterized by its long length .

  According to this, since the rotation of the bolt is stopped by the bulging portion, it is possible to fasten the connection portion and the other terminal with a desired strength without providing another member. In addition, positioning is easy.

  Further, a separate member for securing a space for arranging the head portion of the bolt arranged in the inserted state in the through hole of the connecting portion can be secured on the side of the bulging portion. Etc. can be abolished.

  Further, by arranging the space and the space for attaching the current collector to the housing at a position protruding from the housing, the space for arranging the power generation element can be widened, and the size of the entire storage element can be increased. The capacity of the power storage element can be increased while suppressing the increase.

  The bulging height of the bulging portion is preferably higher than at least the thickness of the head.

  According to this, the bulging portion can sufficiently function as a substitute for a rivet base that adjusts the height of the electrode terminal and the head of the bolt.

  Further, it is preferable that the abutting portion is disposed inside the bulging portion.

  According to this, the space which accommodates an electric power generation element can be ensured more reliably.

  Moreover, it is better that the bulging portion is disposed outside the through hole.

  For example, when the through hole is outside the bulging portion, the position of the current collector is inside. Therefore, it is necessary to reduce the coating area. That is, since the bulging portion serves as an attachment portion for the current collector, a power generation element having a large coating portion area can be employed because the bulging portion is outside the through hole. In addition, since the portion connected to the current collector is outside the space for the power generation element, a space for accommodating the power generation element can be secured in the vertical direction.

  Further, the connection portion may include a flat portion on one side, the entire surface facing outward when attached to the housing.

  As a result, the electrode terminals that are electrically connected to external devices and other batteries do not have a protruding part for attaching the electrode terminals to the housing, and the entire flat part that extends over one surface of the connection part is electrically connected. It becomes possible to use.

  Therefore, it is possible to secure a wide contact area in the electrical connection portion while suppressing an increase in weight with a compact structure of the electrode terminal.

  In addition, the term “storage element” described in the specification and claims is an element capable of electrochemically storing electricity and discharging electricity as required. Specifically, it is described as including a storage battery, a capacitor, a large capacity capacitor, a capacitor, an electrolytic capacitor, an electric double layer capacitor, and the like.

  Further, the contact portion of the electrode terminal may be provided by plastically deforming a tip portion of the shaft portion.

  According to this, it is possible to hold the electrode terminal, the housing, and the current collector with a strong surface pressure, and it is possible to improve the vibration resistance compared to tightening with a nut or the like.

  Further, the shaft portion of the electrode terminal may be provided integrally with the connection portion by being press-fitted into a hole portion provided on the other surface of the connection portion.

  According to this, it is not necessary to manufacture the electrode terminal by forging or the like, and the connection portion made of a material that can ensure mechanical strength and the insertion portion made of a material adopted for electrochemical stability are provided. A combined electrode terminal or the like can be arbitrarily employed.

  The hole portion may include an insertion portion into which the shaft portion is inserted, and an engagement portion extending in a direction intersecting with the direction in which the shaft portion is inserted.

  According to this, even when plastically deforming while rotating the tip of the shaft portion, it is possible to maintain the integrity of the connection portion and the shaft portion against the rotational force.

  According to the present invention, it is possible to prevent the bolt from spinning around without using a separate member and fasten the electrode terminal and the other terminal with a desired strength.

FIG. 1 is a perspective view showing an external appearance of the power storage device of the present embodiment. FIG. 2 is a perspective view schematically showing the inside of the electricity storage device with a part of the housing omitted. FIG. 3 is an exploded perspective view schematically showing the vicinity of the electrode terminal in an exploded state. FIG. 4 is an exploded perspective view schematically showing the vicinity of the electrode terminal in an exploded state with a line of sight opposite to that in FIG. 3. FIG. 5 is a side view showing the vicinity of the electrode terminal in section. FIG. 6 is a perspective view showing another example of the electrode terminal. FIG. 7 is a side view showing the electrode terminal in cross section.

  Next, an embodiment of a power storage device according to the present invention will be described with reference to the drawings. In addition, the following embodiment is only what showed an example of the electrical storage element which concerns on this invention. Accordingly, the scope of the present invention is defined by the wording of the claims with reference to the following embodiments, and is not limited to the following embodiments.

  FIG. 1 is a perspective view showing an external appearance of the power storage device of the present embodiment.

  FIG. 2 is a perspective view schematically showing the inside of the electricity storage device with a part of the housing omitted.

  FIG. 3 is an exploded perspective view schematically showing the vicinity of the electrode terminal in an exploded state.

  FIG. 4 is an exploded perspective view schematically showing the vicinity of the electrode terminal in an exploded state with a line of sight opposite to that in FIG. 3.

  FIG. 5 is a side view showing the vicinity of the electrode terminal in section.

  As shown in these drawings, the power storage device 100 according to the present embodiment is a nonaqueous electrolyte secondary battery that can charge and discharge electricity, and includes a power generation element 101 and a casing 102. An electrode terminal 105 and a current collector 104. In the case of the present embodiment, power storage element 100 further includes a first insulating member 109, a second insulating member 107, and a bolt 108.

  In the present embodiment, the power generation element 101 is a member that can store electricity, including a separator, a negative electrode, and a positive electrode, although detailed illustration is omitted. The negative electrode is formed by forming a negative electrode active material layer on the surface of a long strip negative electrode current collector foil made of copper, for example. The positive electrode is obtained by forming a positive electrode active material layer on the surface of a long belt-shaped positive electrode current collector foil made of aluminum, for example. The separator is, for example, a microporous sheet made of resin.

  The power generation element 101 is a so-called flat winding formed by winding a layered arrangement so that a separator is sandwiched between a negative electrode and a positive electrode so that the whole is formed into an oval shape in the length direction. This is a rotary power generation element.

  Note that the power generation element 101 can adopt not only a flat wound type but also any laminated form such as a wound type or a folded type.

  The housing 102 is a member that houses the power generation element 101. In the case of the present embodiment, the housing 102 includes a container 120 and a lid 103.

  The container 120 is a rectangular (cuboid) member that houses the power generation element 101. The container 120 is made of aluminum or an alloy thereof, or made of thin stainless steel or the like for weight reduction. The container 120 includes a rectangular bottom portion, a rectangular long wall portion standing on each long side portion of the bottom portion, and a rectangular short wall portion standing on each short side portion of the bottom portion. Further, the container 120 constitutes the housing 102 together with the lid 103 by welding the opening end of the container 120 and the lid 103.

  The lid 103 is a metal plate-like member that closes the opening of the container 120, and includes a bulging portion 131 in the present embodiment. The bulging portion 131 is a portion that bulges outward from the housing 102 and has a rectangular shape (square). Further, the bulging portion 131 is a portion formed by pressing a plate-shaped metal member.

  The height of the bulging portion 131 is formed to be higher than at least the thickness of a head 182 (described later) of the bolt 108. This is because the bulging portion 131 adjusts the height between the electrode terminal 105 and the head portion 182 of the bolt 108.

  The current collector 104 is a member that is electrically connected to the electrode terminal 105 and the power generation element 101 and is also physically (mechanically) connected to the housing 102 (lid 103). In the case of the present embodiment, the current collector 104 is arranged in a state where the end portion is fitted to the bulging portion 131.

  The current collector 104 is a metal plate-like member disposed in a bent state along the wall portion and the lid body 103 from the lid body 103 to the wall portion of the housing 102. The current collector 104 is fixedly connected to the lid 103 together with the electrode terminal 105, and is fixed to the negative electrode or the positive electrode of the power generation element 101 by welding or the like and is electrically connected thereto. . Thereby, the power generation element 101 is held by the current collector 104 inside the housing.

  The current collector 104 attached to the negative electrode of the power generation element 101 is made of copper, and the current collector 104 attached to the positive electrode is made of aluminum.

  The electrode terminal 105 is a terminal for electrically connecting an external device, another battery, or the like to the power storage element 100, and includes a connection portion 151, a shaft portion 152, a contact portion 153, a through hole 154, and the like. It has.

  In the case of the present embodiment, the electrode terminal 105 is manufactured by integrally forming the shaft portion 152 and the connecting portion 151 by forging. The electrode terminal 105 arranged on the positive electrode side is made of a material mainly made of aluminum, and the electrode terminal 105 arranged on the negative electrode side is made of a material mainly made of copper.

  The connecting portion 151 is a member having a plate-like conductivity having a flat portion 155 on the entire surface, the entire surface facing outward when attached to the housing 102 in a single plane. The connection portion 151 is a portion that directly contacts the current-carrying member 200 such as a bus bar or other electrode terminal when the electrical storage element 100 is electrically connected to an external device or another battery. The flat portion 155 having the maximum area of the portion 151 is in direct contact with the energizing member 200, thereby realizing a wide contact area.

  The shaft portion 152 is provided integrally with the connection portion 151 so as to protrude from the other surface opposite to the flat surface portion 155 in the direction intersecting the flat surface portion 155 (Z direction in the drawing), and the housing 102 and the current collector It is a member having a rod-like conductivity arranged in the body 104 in an inserted state. In the case of the present embodiment, the shaft portion 152 is a member similar to a metal rivet, and includes a hole provided in the first insulating member 109, a hole provided in the lid 103 (the bulging portion 131), This is a portion that generates a clamping force while maintaining the distance between the connecting portion 151 and the contact portion 153 while being pierced through the hole provided in the two insulating members 107 and the hole provided in the current collector 104. The first insulating member 109 is interposed between the shaft portion 152 and the lid body 103, and the shaft portion 152 is electrically connected to the current collector 104 connection portion 151, and Is insulative.

  The abutting portion 153 is a member that cooperates with the connecting portion 151 and sandwiches the housing 102 and the current collector 104 via the shaft portion 152, and is a portion provided at the tip portion of the shaft portion 152. In the case of the present embodiment, the contact portion 153 is a portion provided by plastically deforming the tip portion of the shaft portion 152. More specifically, the shaft portion 152 is pierced in the overlapping direction with respect to the first insulating member 109, the lid body 103, the second insulating member 107, and the current collector 104 stacked in this order. After the arrangement, the contact portion 153 is formed by plastically deforming the tip portion of the shaft portion 152 using a tool. In order to sandwich the overlapped portion with the connecting portion 151, the contact portion 153 is formed by plastic deformation so that the shaft portion 152 extends in a flange shape and the shaft portion 152 becomes shorter. . These are similar to fastening by so-called rivet caulking.

  Note that the contact portion 153 is not only due to plastic deformation of the shaft portion 152 but also provided with a male screw on the shaft portion 152 and screwing the nut-shaped contact portion 153 to the shaft portion 152 so that the tip of the shaft portion 152 May be provided.

The through-hole 154 is a hole through which the bolt 108 for passing through the connecting portion 151 in a direction intersecting the flat portion 155 and electrically connecting the other device and the connecting portion 151 is inserted. Further, the through hole 154 is disposed at a position where the bulging portion 131 and the head portion 182 interfere when the head portion 182 of the inserted bolt 108 tries to rotate. That is, the distance between the rotation axis of the bolt 108 inserted into the through hole 154 and the most protruding portion of the head 182 is the hole axis of the through hole 154 and the side wall facing the through hole 154 of the bulging portion 131. not the length than the distance between.

  In the case of the present embodiment, the through hole 154 is substantially parallel to the central axis of the shaft portion 152 on the side of the bulging portion 131 in a state where the shaft portion 152 is inserted into the bulging portion 131 provided in the housing 102. It is arranged to line up. More specifically, the position of the through hole 154 is a position where the bolt 108 and the bulging portion 131 can be close enough to maintain insulation by the first insulating member 109 in a state where the bolt 108 is inserted into the through hole 154. Is provided. Thereby, it can avoid that the connection part 151 enlarges, and can suppress the weight increase of the electrical storage element 100 whole.

  Further, the through hole 154 is disposed inside the bulging portion 131. This is because if the through-hole 154 is placed outside the bulging portion 131, the position of the current collector 104 is arranged inside, and the area of the coating portion of the power generation element 101 must be reduced. That is, since the bulging portion 131 serves as an attachment portion of the current collector 104, the bulging portion 131 is outside the through-hole 154, so that the power generation element 101 having a large coating portion area can be employed. . In addition, since the portion connected to the current collector 104 is outside the space of the power generation element 101, a space for accommodating the power generation element 101 can be secured in the vertical direction.

  The bolt 108 is used to electrically and physically connect the current-carrying member 200 (see FIG. 3) for electrically connecting to an external device or another battery, for example, the current-carrying member 200 such as a bus bar, to the electrode terminal 105. It is a member. In the case of the present embodiment, the bolt 108 includes a screw portion 181 and a head portion 182 so that the energizing member 200 can be detachably fastened, and after the screw portion 181 is inserted through a hole provided in the energizing member 200. By tightening with the nut 201, the connecting portion 151 of the electrode terminal 105 and the energizing member 200 are connected in a sandwiched state.

  The first insulating member 109 is a member that electrically insulates the housing 102 and the bolt 108, and the housing 102 (the bulging portion 131) and the electrode terminal 105. In the case of the present embodiment, the first insulating member 109 is a plate-like member formed of an insulator such as resin, and covers the bulging portion 131 and has a shape that accommodates the head 182 of the bolt 108. It has become.

  The second insulating member 107 is a member that electrically insulates the housing 102 and the current collector 104. In the case of the present embodiment, the second insulating member 107 is a thin box-shaped member formed of an insulator such as a resin, and is disposed in the bulging portion 131 in a fitted state from the inside of the housing 102. Yes.

  With the above configuration, when the current-carrying member 200 pierced by the bolt 108 is tightened with the nut 201 and the electrode terminal 105 and the current-carrying member 200 are fastened, the planar connection portion 151 and the current-carrying member 200 have a wide contact area. Since it is connected, it is possible to reduce power loss at the connection portion.

  Further, since the rotation of the bolt 108 is stopped by the bulging portion 131, it is possible to fasten the connecting portion 151 and another terminal such as a bus bar with a desired strength without providing a separate member. In addition, positioning is easy.

  In addition, a space for placing the head portion 182 of the bolt 108 that is inserted in the through hole 154 of the connecting portion 151 can be secured to the side of the bulging portion 131, and a space for placing the head portion 182 is secured. It becomes possible to abolish another member for doing.

  Further, by arranging the space for attaching the current collector 104 to the housing 102 at a position protruding from the housing 102, the space for arranging the power generation element 101 can be widened, and the size of the entire storage element 100 can be increased. It is possible to increase the capacity of the power storage element 100 while suppressing the increase in the power consumption.

  Next, another example of the electrode terminal 105 will be described.

  FIG. 6 is a perspective view showing another example of the electrode terminal.

  FIG. 7 is a side view showing the electrode terminal in cross section.

  As shown in the figure, the electrode terminal 105 has a shaft portion 152 and a connecting portion 151 that are initially separated from each other by press-fitting the shaft portion 152 into a hole 157 provided in the other surface 156 of the connecting portion 151. It is integrally formed.

  The hole portion 157 includes an insertion portion 158 into which the shaft portion 152 is inserted, and an engagement portion that extends in a direction (in the XY plane in the drawing) intersecting the direction in which the shaft portion 152 is inserted (Z-axis direction in the drawing). 159 and a flange forming portion 160.

  By forming the engagement portion 159 in the hole portion 157 provided in the connection portion 151, the shaft portion 152 is plastically deformed so as to fill the engagement portion 159 when the shaft portion 152 is press-fitted, and the connection portion It is possible to prevent the shaft portion 152 from rotating with respect to 151. In addition, since the flange portion 160 is also filled with the shaft portion 152, when the housing 102 or the current collector 104 is sandwiched between the connection portion 151 and the contact portion 153 via the shaft portion 152, strong clamping is performed. Force can be generated.

  In addition, this invention is not limited to the said embodiment. For example, another embodiment realized by arbitrarily combining the components described in this specification and excluding some of the components may be used as an embodiment of the present invention. In addition, the present invention includes modifications obtained by making various modifications conceivable by those skilled in the art without departing from the gist of the present invention, that is, the meaning described in the claims. It is.

  The present invention can be used for a power storage element such as a secondary battery, and in particular, can be used for a power storage element mounted on an automobile or the like that requires a large current for a long time.

DESCRIPTION OF SYMBOLS 100 Power storage element 101 Power generation element 102 Case 103 Lid 104 Current collector 105 Electrode terminal 107 Second insulating member 108 Bolt 109 First insulating member 120 Container 131 Swelling portion 151 Connection portion 152 Shaft portion 153 Contact portion 154 Through hole 155 Plane portion 156 Other surface 157 Hole portion 158 Insertion portion 159 Engagement portion 160 Flange formation portion 181 Screw portion 182 Head 200 Current-carrying member 201 Nut

Claims (8)

A power storage element comprising: a power generation element; a housing that houses the power generation element; and an electrode terminal that enables electrical connection to the power generation element from outside the housing via a current collector,
The electrode terminal is
A plate-like connecting portion having a plane ;
A rod-shaped shaft portion that is provided integrally with the connection portion in a protruding state in a direction intersecting the plane, and is disposed in an inserted state in the current collector;
An abutting portion provided at a tip portion of the shaft portion and in contact with the current collector;
A through-hole through which the bolt for passing through the connecting portion in a direction intersecting the plane and electrically connecting the other device and the connecting portion is inserted;
The housing includes a bulging portion that bulges outward,
The shaft portion of the electrode terminal is arranged in a state of being inserted through the bulging portion,
The through hole is located on a side of the bulging portion and at a position where the bulging portion and the head interfere with each other when the head of a bolt inserted through the through hole is about to rotate. ,
The distance between the rotation axis of the bolt inserted into the through hole and the most protruding portion of the head is between the hole axis of the through hole and the side wall of the bulging portion facing the through hole. A power storage element longer than the distance . The power storage element according to claim 1, wherein a bulging height of the bulging portion is higher than at least a thickness of the head. The electric storage element according to claim 1, wherein the contact portion is disposed inside the bulging portion. The power storage device according to claim 1, wherein the bulging portion is disposed outside the through hole. The electrical storage element according to any one of claims 1 to 4, wherein the connection portion includes a flat portion on one side, the entire surface facing outward when attached to the housing. The storage element according to claim 1, wherein the contact portion of the electrode terminal is provided by plastically deforming a tip portion of the shaft portion. The power storage device according to claim 1, wherein the shaft portion of the electrode terminal is integrally provided in the connection portion by being press-fitted into a hole portion provided on the other surface of the connection portion. The hole is
An insertion part into which the shaft part is inserted;
The electricity storage device according to claim 7, further comprising an engaging portion extending in a direction intersecting with a direction in which the shaft portion is inserted.

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