JP5476794B2 - battery - Google Patents

Description

  The present invention includes a battery case having a substantially flat lid portion, and a power generation element having a pair of electrode plates and a current collector connected to the electrode plates are arranged in the battery case, and The present invention relates to a battery in which an electrode terminal connected to an electric body passes through the lid and is drawn to the outside.

As a general structure of such a battery, for example, as described in Patent Document 1 below, a current collecting element is used for a power generation element in which a pair of electrode plates coated with an active material or the like are combined in a roll shape with a separator interposed therebetween. A body is connected to each of a pair of electrode plates, and electrode terminals arranged so as to be connected to the current collector are drawn out from the inside of the battery housing.
With respect to a method of pulling out the electrode terminal to the outside through a hole formed in the lid plate portion of the battery casing, as disclosed in Patent Document 1, a rivet is provided as a component of the electrode terminal, and the rivet is formed in the hole of the lid plate. Generally, a method of securing electrical connection and airtightness by caulking with a gasket in a passed state is generally used.
In recent years, as disclosed in Patent Document 2 below, there has been an idea of applying a technique for joining a metal and a resin to attachment of an electrode terminal to a battery casing (cover plate). In this method, an electrode terminal is passed through a hole in the cover plate, and the hole is sealed with resin together with the electrode terminal.

JP 2002-324541 A JP 2008-173967 A

Of the electrode terminal configuration methods described above, the method of using rivets is the use of rivets that are independent of other components in the component parts of the electrode terminals. It will be complicated.
In addition, the method of attaching electrode terminals using metal / resin bonding technology can simplify the structure, but the structure in which the electrode terminals are sealed with resin through holes formed in the cover plate is insufficient. May end up.
The present invention has been made in view of such circumstances, and an object of the present invention is to simplify the configuration of the electrode terminal while sufficiently securing the attachment strength of the electrode terminal.

A first invention of the present application includes a battery casing having a substantially flat lid portion, and a power generation element having a pair of electrode plates in the battery casing and a current collector connected to the electrode plates. In the battery in which the electrode terminal arranged and connected to the current collector passes through the lid part and is drawn to the outside, the electrode terminal is on both the inner side and the outer side of the battery casing. the consists in bent shape and the plate-like member so as to have a portion to be a posture along the lid in the vicinity of the lid portion, and the electrode terminal and the lid portion, the battery housing in the electrode terminal A portion that is in a posture along the lid on the inner side of the battery, a portion that is in a posture along the lid on the outer side of the battery casing in the electrode terminal, and a portion that penetrates the lid in the electrode terminal , The electrode terminal and the lid Metal in a state in which the resin is present in the - are joined by resin bonding is constructed.

That is, the basic configuration is such that the electrode terminal is passed through the substantially flat lid portion and sealed with resin.
However, it is not a structure that simply fills the part where the electrode terminal is passed with the resin, but the electrode terminal and the lid are made strong through the resin by using the electrode terminal made of a plate-like member. Connect to.
For this reason, the electrode terminal is formed by bending a plate material or the like so as to have a portion in the posture along the lid portion, and the portion in the posture along the lid portion is joined to the lid portion through the resin.
As a result, the electrode terminal is fixed to the lid portion over a wide area, and the sealed state is stably maintained even if a force such as kinking acts on the electrode terminal.
In addition, the electrode terminal is formed of a plate-like member and pulled out of the battery casing, so that it can be easily fixed to the bus bar (bolt electric wiring member such as a metal plate) with a bolt. .

Further, the second invention of the present application is configured by integrally forming the electrode terminal and the current collector in addition to the structure of the first invention.
That is, the electrode terminal is attached to the battery casing by metal-resin bonding, so that the degree of freedom of shape of the electrode terminal is increased, and the electrode terminal is formed of a plate-like member so as to be integrally formed with the current collector. It became possible.

According to a third invention of the present application, in addition to the configuration of the first or second invention, the battery case covers the rectangular lid on the open surface of the bottomed rectangular cylindrical can. The electrode terminal is formed by bending approximately 90 degrees along the connecting portion between the end portion on the short side of the lid portion and the can body in the battery casing. ing.
Further, in addition to the configuration of any one of the first to third inventions, a terminal bolt for connecting the electrode terminal to a wiring component is provided on the outer portion of the battery casing in the electrode terminal. The threaded portion of the bolt is attached in a posture that penetrates the electrode terminal, and the electrode terminal directly or indirectly receives the rotational force that acts on the head of the terminal bolt when the wiring component is attached. The electrode terminal may be formed in a bent shape near the head of the terminal bolt so as to be stopped .
In other words, since the electrode terminal is configured as a plate-like member, it is easy to make the electrode terminal bent, and the terminal formed when the wiring component is attached on the surface formed by the bent shape. The rotational force acting on the head of the bolt is received and the terminal bolt is prevented from rotating.
As a result, the electrode terminal can be used for stopping the terminal bolt only by making the plate-like member bent, and the electrode structure of the battery can be further simplified.

According to the first aspect of the present invention, the electrode terminal formed of the plate-like member can be firmly attached to the lid portion of the battery by metal-resin bonding only by bending the electrode terminal by bending or the like. The structure of the electrode terminal can be simplified while sufficiently securing the mounting strength.
Furthermore, when the electrode terminal is positioned along the lid in the battery case, the volume of the space required for the presence of the electrode terminal in the battery case is made as small as possible to reduce wasted space. And volume efficiency can be improved.
Further, according to the second aspect, the electrode terminal and the current collector are integrally formed to reduce the number of parts, thereby further simplifying the configuration of the electrode terminal .

The principal part perspective view concerning embodiment of this invention Sectional drawing of the principal part concerning embodiment of this invention The principal part side view concerning embodiment of this invention Sectional drawing of the principal part concerning another embodiment of this invention

Hereinafter, embodiments of the battery of the present invention will be described with reference to the drawings.
In the present embodiment, a non-aqueous electrolyte secondary battery (more specifically, a lithium ion battery) which is an example of a secondary battery will be described as an example.

[Configuration of Nonaqueous Electrolyte Secondary Battery RB]
As shown in the perspective view of FIG. 1 and the side view of FIG. 3, the non-aqueous electrolyte secondary battery RB of the present embodiment has a bottomed cylindrical shape (more specifically, shown by a one-dot chain line in FIG. 3). The battery case BC is formed by covering the open surface of the can body 1 (bottom rectangular tube shape) with a substantially flat lid portion 2 and welding it. As shown in FIG. 1, the lid portion 2 is formed in a strip-like rectangle, and the battery casing BC has a flat rectangular parallelepiped shape as a whole.

Inside the battery casing BC, the power generation element 3 and current collectors 4 and 6 indicated by a two-dot chain line in FIGS. 1 and 3 are housed and disposed in a state of being immersed in the electrolytic solution. The power generation element 3 is configured by applying an active material to each of a pair of electrode plates composed of a foil-like positive electrode plate and a foil-like negative electrode plate, and winding the separator with a separator interposed therebetween.
In the power generation element 3, the foil-like positive electrode plate is extended to the side and welded to the current collector 4, and the foil-like negative electrode plate is extended to the opposite side and welded to the current collector 6.

The lid portion 2 made of metal (specifically, aluminum) includes a positive electrode current collector 4 and a positive electrode terminal 5 connected to the current collector 4, a negative electrode current collector 6, and a collector thereof. A negative electrode terminal 7 connected to the electric body 6 is attached in a state of being supported by the support portions 10 and 11 made of resin.
Terminal bolts 8 and 9 are attached to end portions of the outer portion of the battery casing BC in the electrode terminal 5 on the positive electrode side and the electrode terminal 7 on the negative electrode side. The terminal bolts 8 and 9 have heads embedded in the support portions 10 and 11, and screw portions 8 a and 9 a that pass through holes formed in the electrode terminals 5 and 7 in the normal direction of the lid portion 2. It is mounted in a protruding position. The terminal bolts 8 and 9 are for connecting and fixing the electrode terminals 5 and 7 to wiring components such as so-called bus bars with nuts for electrical wiring with other batteries or the like. In order to perform electrical wiring in such a connection type, the electrode terminals 5 and 7 are constituted by plate-like members.

The positive current collector 4 and electrode terminal 5 and the negative current collector 6 and electrode terminal 7, including the support portions 10 and 11, are symmetrical with respect to the longitudinal center of the lid portion 2. It is in a relationship that is arranged in a posture. Only the material constituting the positive electrode side and the negative electrode side is different. Specifically, the material of the current collector 4 and the electrode terminal 5 on the positive electrode side is aluminum, and the current collector 6 and the electrode terminal 7 on the negative electrode side are copper.
Therefore, only the configuration on the positive electrode side will be described on behalf of both.

The electrode terminal 5 and the current collector 4 formed of a plate-like member are not formed of separate members, but are integrally formed from a single plate material (aluminum plate).
After punching a single plate material into a predetermined shape or cutting it into a predetermined shape, the current collector 4 portion and the electrode terminal 5 portion are bent into the shape shown in FIG.
The electrode structure on the positive electrode side will be described in more detail with reference to FIG. 2 which is a cross-sectional view. At a position near the current collector 4 side in the electrode terminal 5, the position indicated by arrow A, the position indicated by arrow B and arrow C in FIG. Are bent at approximately 90 degrees with the bending directions being alternated. Thereby, a stepped step is formed on the electrode terminal 5.

  The current collector 4 and the electrode terminal 5 that are formed in such a continuous state are such that the current collector 4 is positioned inside the battery casing BC, and the electrode terminal 5 passes through the lid portion 2 to be connected to the battery. Since the positional relationship is exposed to the outside of the housing BC, the lid portion 2 to which the electrode terminal 5 is attached is formed with a slit-shaped hole 2a through which the electrode terminal 5 is inserted. The electrode terminal 5 passes through the hole 2a and is drawn out of the battery casing BC.

The electrode terminal 5 is attached to the lid 2 by so-called metal-resin bonding.
This metal-resin bonding is a technique for firmly bonding a metal and a resin. For example, the surface of the metal is surface-treated to form a minute recess, and the surface-treated metal is placed in a mold to form a resin. Injection molding.
Specifically, after the above-mentioned surface treatment is performed on the member in which the current collector 4 and the electrode terminal 5 are integrally formed, and the lid portion 2, the electrode terminal 5 is passed through the hole 2a of the lid portion 2, Further, the threaded portion 8a of the terminal bolt 8 is passed through the hole at the end of the electrode terminal 5 and is placed in the mold in the posture shown in FIG.
The mold used here is configured such that the resin flows in the shape of the support portion 10 shown in FIGS.
An assembly of the lid portion 2 having the structure shown in FIG. 2 is completed by injection molding the resin with this mold.
Although the above has described the electrode terminal 5 and the like on the positive electrode side, the operation is also performed on the electrode terminal 7 and the like on the negative electrode side at the same time.

In the assembly of the lid portion 2 shown in FIG. 2, the portion of the current collector 4 extends to the lid portion 2 side along the side surface of the can 1 and continues to the electrode terminal 5. In the portion of the electrode terminal 5, on the inner side of the battery casing BC, it is bent approximately 90 degrees at the position indicated by the arrow A in FIG. Is bent approximately 90 degrees in the opposite direction. The electrode terminal 5 bent at the position indicated by the arrow B extends toward the outside of the battery casing BC and passes through the hole 2a of the lid 2.
Immediately after passing through the hole 2a, the electrode terminal 5 bends approximately 90 degrees in a direction opposite to the position of the arrow B at the position indicated by the arrow C, and reaches the attachment position of the terminal bolt 8.

Thus, by forming the electrode terminal 5 into a bent shape that bends approximately 90 degrees at the position indicated by the arrow A and the position indicated by the arrow B, the shape of the electrode terminal 5 is indicated by the arrow B from the position indicated by the arrow A. In the range up to the position, the posture is along the lid 2 in the vicinity of the lid 2.
The resin constituting the support portion 10 that supports the electrode terminal 5 is between the electrode terminal 5 and the lid portion 2 so as to cover the periphery of the electrode terminal 5 in a portion along the lid portion 2. Exists. Accordingly, the lid 2 and the electrode terminal 5 are arranged in a posture in which the surfaces face each other, and between the resin of the support portion 10 and the lid portion 2 and between the resin of the support portion 10 and the electrode terminal 5. Since they are bonded by metal-resin bonding, both are firmly bonded.

  A portion of the electrode terminal 5 in a posture along the lid 2 is also present outside the battery housing BC, and the battery housing of the electrode terminal 5 from a position indicated by an arrow C where the electrode terminal 5 is bent by approximately 90 degrees. The portion up to the outer end of the body BC is also in a posture along the lid portion 2. In this portion, not only the resin constituting the support portion 10 but also the head 8b of the terminal bolt 8 exists between the electrode terminal 5 and the lid portion 2, but the support portion is between the electrode terminal 5 and the lid portion 2. 10 is present, and the resin constituting the support portion 10 and the electrode terminal 5 and the resin constituting the support portion 10 and the lid portion 2 are firmly bonded by metal-resin bonding. This contributes to stable support of the electrode terminals 5.

  In addition, even in the portion of the electrode terminal 5 that passes through (through) the hole 2a of the lid portion 2, there is a resin that constitutes the support portion 10 in a state where the space between the electrode terminal 5 and the hole 2a is densely filled. Then, the resin of the support portion 10 and the electrode terminal 5 and the resin of the support portion 10 and the lid portion 2 are joined by metal-resin bonding so that airtightness is maintained, and the electrode terminal 5 is maintained. And the lid 2 are ensured to be insulated.

Further, the support portion 10 surrounds the periphery of the head 8b of the terminal bolt 8, and prevents the terminal bolt 8 from rotating around the rotation axis when the wiring component is connected and fixed to the electrode terminal 5 with the terminal bolt 8 and the nut. I am doing. However, the resin of the support portion 10 alone does not necessarily have a sufficient anti-rotation effect when a strong rotational force acts on the terminal bolt 8, but the vertical wall portion from the position of arrow B to the position of arrow C in the electrode terminal 5 is Even if a strong rotational force acts on the terminal bolt 8 by being present, deformation of the resin of the support portion 10 existing between the vertical wall portion and the head portion 8b of the terminal bolt 8 is prevented, and the electrode terminal 5 Contributes to stopping the terminal bolt 8 from rotating.
In other words, by forming the electrode terminal 5 in a bent shape of approximately 90 degrees at the position indicated by the arrow C near the head 8b of the terminal bolt 8 and forming a vertical wall portion along the screwing direction of the screw portion 8a, The rotational force acting on the head 8b when mounting wiring parts such as a bus bar is indirectly received.

[Another embodiment]
Hereinafter, other embodiments of the present invention will be listed.
(1) In the above embodiment, the case where the electrode terminals 5 and 7 are formed in a bent shape and the rotational force acting on the heads of the terminal bolts 8 and 9 is indirectly received is described as an example. However, as shown in FIG. 4 corresponding to FIG. 2, the electrode terminals 5 and 7 are formed in a bent shape so that the rotational force acting on the heads of the terminal bolts 8 and 9 is directly received. It may be configured.
In FIG. 4, parts corresponding to those shown in FIG.
In the structure shown in FIG. 4, the vertical wall portion at the position indicated by the arrow C is applied to the head 8 b of the terminal bolt 8, and the rotational force acting on the head 8 b is directly received by the electrode terminal 5.
In the structure shown in FIG. 4, the end of the battery terminal BC outside the electrode terminal 5 is further extended and bent toward the head 8b side of the terminal bolt 8 (position indicated by the arrow D in FIG. 4). In this configuration, the head portion 8b is surrounded by the electrode terminal 5 in a U-shape so that the rotational force acting on the head portion 8b when the wiring component is attached is directly received.
Even when the head 8 b of the terminal bolt 8 is surrounded by the electrode terminal 5 in a U-shape, the rotational force acting on the head 8 b is received, and the rotational force is directly received by the electrode terminal 5. Instead of stopping, the electrode terminal 5 may receive the rotational force acting on the head 8b indirectly through the resin of the support portion 10.

(2) In the above embodiment, the case where the present invention is applied to a lithium ion battery which is a non-aqueous electrolyte secondary battery is exemplified, but various secondary batteries such as a nickel metal hydride battery, It can also be applied to primary batteries.

DESCRIPTION OF SYMBOLS 1 Can body 2 Cover part 2a Hole 3 Power generation element 4,6 Current collector 5,7 Electrode terminal 8,9 Terminal bolt BC Battery housing

Claims (3)

A battery casing having a substantially flat lid portion is provided, and a power generation element having a pair of electrode plates and a current collector connected to the electrode plates are arranged in the battery casing, and are connected to the current collector. The electrode terminal is a battery configured to penetrate the lid portion and be drawn outside,
The electrode terminal is constituted by a plate-like member having a bent shape so as to have a portion along the lid in the vicinity of the lid on both the inner side and the outer side of the battery casing ,
The electrode terminal and the lid portion are a portion of the electrode terminal that is in a posture along the lid portion on the inner side of the battery housing, and a posture of the electrode terminal along the lid portion on the outer side of the battery housing. And a portion of the electrode terminal that passes through the lid portion, and is joined by metal-resin bonding in a state where resin exists between the electrode terminal and the lid portion.   The battery according to claim 1, wherein the electrode terminal and the current collector are integrally formed. The battery casing is formed in a flat rectangular parallelepiped shape by covering the rectangular lid on the open surface of the bottomed rectangular cylindrical can.
3. The battery according to claim 1 , wherein the electrode terminal is formed by being bent approximately 90 degrees along a connection portion between a short-side end of the lid and the can in the battery casing. .

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