JP2003197176A - Battery - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a battery with high reliability for a long time by preventing the rotation of a positive terminal and a negative terminal together with a fixing nut in the manufacture and use of the battery. <P>SOLUTION: This battery 50 has a power generating element 51 having metal foils acting as a negative electrode and a positive electrode; current collecting plates connected to the edges in the surface direction of the metal foils by electric resistance welding; a pair of positive terminal 53 and negative terminal 54 connected to the current collecting plates respectively extending in the direction parting from the power generating element; a container 52 housing the power generating element 51; and a cover plate 62 through which the positive terminal 53 and the negative terminal 54 are passed and sealing the container 53. The positive terminal 53 and the negative terminal 54 each has a flange part 70, a screw part 71, and a tip part 72, and is fixed to the cover plate 62 by screwing a fixing nut 76 to the screw part 71. Each of the tip parts 72 has bifacial widths facing the shaft line of each of the positive terminal 53 and the negative terminal 54 so that a plain shape viewed along the shaft line direction is other than a complete circle. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a battery, and more particularly to a medium to large capacity battery such as a nickel hydrogen battery or a lithium ion battery.

[0002]

2. Description of the Related Art In recent years, the demand for small-sized batteries has been increasing with the advancement of technologies for portable information terminals and the like. On the other hand, stationary batteries used for emergency uninterruptible power supplies installed in computer systems, buildings, etc. and batteries used as mobile power supplies for electric vehicles such as electric vehicles (hereinafter referred to as EV),
Batteries with medium to large capacity of several tens to several hundreds Ah have been demanded. For example, in an EV battery, 100
High output characteristics to withstand large current load of A (ampere) or more,
High energy density and maintenance-free, highly reliable airtightness are required.

As battery systems used for these, alkaline batteries such as nickel cadmium storage batteries and nickel hydride storage batteries have been developed in addition to lead storage batteries. Development is also underway for lithium-ion batteries. A sealed battery 10 as shown in FIG. 8 is used for such a nickel-cadmium battery, a nickel-hydrogen storage battery, and a lithium-ion battery. In this sealed battery 10, a power generating element 11 having a positive electrode and a negative electrode is housed through a separator from an opening 12a of a battery case 12.

A positive terminal 13 is provided on the rear end side (upper side in the figure) of the power generating element 11 with respect to the housing direction of the power generating element 11.
Further, the negative electrode terminal 14 is provided in a state where the pole portions 15, 15 (upper part in the figure) are exposed to the outside of the battery case 12. Also, battery case
The lid plate 22 is fitted into the opening 12 a of the twelve. That is,
The lid plate 22 includes a pole portion 15 of the positive electrode terminal 13 and the negative electrode terminal 14.
The flat plate portion 25 has through-holes 23, 23 through which the respective holes are inserted, and the side end of the flat plate portion 25 has a rising portion 25a bent in a substantially L shape.

Then, the lid plate 22 exposes the pole portions 15 of the positive electrode terminal 13 and the negative electrode terminal 14 to the outside of the battery case 12 through the through holes 23, 23 with the inside of the battery case 12 closed. Has become. Further, the positive electrode terminal 13 includes a lead metal fitting 16 and a lead plate 17.
And a positive electrode current collector of the power generation element 11 via the positive electrode current collector plate 18.
Connected to 19. Further, the negative electrode terminal 14 is connected to the negative electrode current collector plate 20.
Is connected to the negative electrode current collector 21 of the power generation element 11.

As shown in FIG. 9A, when the sealed battery 10 is a nickel-cadmium battery or a nickel-hydrogen storage battery, the positive electrode current collector 19 and the negative electrode current collector 20 have a thickness of, for example, 0.1. A relatively thick steel plate having a thickness of about mm is used, and the positive electrode current collector 19 and the negative electrode current collector 19 are formed in the substantially comb-shaped slits 18a and 20a formed in the positive electrode current collector plate 18 and the negative electrode current collector plate 20. The body 20 is inserted one by one, and the edges of the positive electrode current collector 19 and the negative electrode current collector 20 protruding from the slits 18a, 20a are melted by gas welding or the like, so that the positive electrode current collector plate 18 and the negative electrode current collector plate 20 and the positive electrode current collector 19 and the negative electrode current collector 21 are integrally joined.

On the other hand, as shown in FIG. 9B, when the sealed battery 10 is a lithium ion battery, the positive electrode current collector 19 and the negative electrode current collector 21 have a thin metal thickness of 10 μm to 50 μm. Foil is used. Specifically, the positive electrode current collector
An aluminum foil with a thickness of 20 μm is used as 19, and a copper foil with a thickness of 14 μm is used as the negative electrode current collector 21. The positive electrode current collector 19 and the negative electrode current collector 21 as described above are bent portions having a substantially V-shaped cross section and extending in parallel from the positive electrode current collector plate 18 and the negative electrode current collector plate 20 as a set of a plurality of sheets. 100 (only one is shown in FIG. 9 (B)), and the bent portion 100 is welded by laser welding, electric resistance welding or the like at the exposed portion from the notch 100a of each bent portion 100. Positive electrode current collector plate 18 through
And joined to the negative electrode current collector plate 20.

The positive electrode terminal 13 and the negative electrode terminal 14 are
As shown in FIG. 10, it has a pole portion 15, a collar portion 46 provided on the lower end of the pole portion 15, and a screw portion 47 provided on the upper side of the collar portion 46. Then, by screwing the fixing nut 48 into the screw portion 47 from above the flat plate portion 25 of the lid plate 22,
The positive electrode terminal 13 and the negative electrode terminal 14 are fixed to the cover plate 22. The cover plate 22 is provided with a communication hole 36a, and a rupture valve 38 that closes the communication hole 36a prevents an abnormal increase in the battery internal pressure.

Further, as shown in FIG. 11, the sealed battery 10 is
A connecting member is provided between the pole portions 15 of the positive electrode terminal 13 and the negative electrode terminal 14.
41 and the male screw portion formed on the outer surface 15 of the pole portion of the positive electrode terminal 13 and the negative electrode terminal 14, and the connecting nut 42
Multiple sealed batteries by screwing each
It can be modularized by connecting 10 in series or in parallel.

In order to obtain high output characteristics, the sealed battery 10 minimizes the electric resistance of the positive electrode terminal 13 and the negative electrode terminal 14 itself, the contact resistance between the positive electrode terminal 13 and the negative electrode terminal 14 and the electrode and the external connecting member 41, and the like. It is required to keep it to the limit. Further, in order to ensure highly reliable airtightness, airtightness and liquid-tightness of the positive electrode terminal 13 and the negative electrode terminal 14 are particularly required. Above all,
Lithium-ion batteries require extremely high degree of hermeticity.

That is, in a water-based sealed battery such as a lead battery or an alkaline battery, the airtightness is not sufficient, and even if water enters or leaks between the inside and the outside of the battery, the battery performance is not adversely affected. Does not reach. However, in the lithium-ion battery, if water enters from the outside,
This will cause a significant decrease in battery performance.

In particular, when LiPF ₆ or the like, which is an electrolyte salt that gives good battery performance, is used, the degree of adverse effect due to water penetration is extremely high. For this reason, a typical lithium-ion battery has a metal battery case and lid sealed by laser welding or the like, and at the terminal portion, a material called glass or ceramic, called a hermetic seal, is used for airtightness. Has been devised to complete the.

Further, in the case of the sealed type battery 10, particularly in the case of a lithium ion battery which is required to be more airtight than a nickel hydrogen battery, the flange portions 46 of the positive electrode terminal 13 and the negative electrode terminal 14 and the cover plate 22.
An O-ring is disposed as a packing (not shown) so as to circulate around the screw portion 47 between the O-ring and the back surface of the O-ring.

[0014]

By the way, in order to fix the positive electrode terminal 13 and the negative electrode terminal 14 to the cover plate 22, the conventional sealed battery 10 has a fixing nut on the screw portion 47 from the upper side of the cover plate 22.
When the 48 is screwed in, the positive electrode terminal 13 and the negative electrode terminal 14 may rotate together with the fixing nut 48.

Particularly, in the case of a lithium ion battery, since there is an O-ring (not shown) between the collar portion 46 and the cover plate 22, the positive electrode terminal 13 and the negative electrode terminal 14 are more easily rotated. was there.

Further, when an O-ring (not shown) is used as the packing, an extremely thin metal foil is used for the power generating element 11, so that even if the positive electrode terminal 13 or the negative electrode terminal 14 rotates even a little, There is a problem that the current collector plate 18 and the negative electrode current collector plate 20 are torn from the positive electrode and the negative electrode, respectively.

Therefore, an object of the present invention is to solve the above-mentioned problems, and to prevent the positive electrode terminal and the negative electrode terminal from being rotated together with the fixing nut at the time of manufacturing and using the battery, thereby improving long-term reliability. The purpose is to provide excellent batteries.

[0018]

According to the present invention, as described in claim 1, a power generating element having a negative electrode and a positive electrode is connected via a separator to the surface edges of the negative electrode and the positive electrode. A current collector, a pair of terminals that are joined to the current collectors and extend in a direction away from the power generating element, a battery case that accommodates the power generating element, and a battery case in which the terminals penetrate and A lid plate for sealing, wherein the terminal has a flange portion that faces the back surface of the lid plate, a screw portion that is inserted into an insertion hole of the lid plate, and the terminal integrated with the screw portion. A battery having a tip portion protruding to the front surface side of the plate, wherein the terminal is fixed to the cover plate by screwing a fixing nut onto the screw portion, the battery being arranged along the axial direction of the tip portion. It is characterized in that the planar shape seen from There.

Here, as the planar shape of the tip portion viewed along the axial direction, for example, a polygonal shape, an elliptical shape, or a planar shape formed by combining an arbitrary number of one or both of straight lines and curved lines can be adopted. . In addition,
As such a planar shape, an even polygon such as a quadrangle, a hexagon, and an octagon having a width across flats with which a commercially available tool can be engaged is preferable.

According to the battery of the present invention, since the planar shape of the tip portion viewed along the axial direction is other than a perfect circle, a dedicated tool having an opening corresponding to the planar shape of the tip portion is prepared in advance. If the terminal is fixed by engaging a tool with the tip end, it is possible to prevent the terminal from rotating together with the fixing nut when the fixing nut is screwed into the screw of the terminal. In particular, if the planar shape of the tip portion as viewed in the axial direction has a width across flats, the terminal can be fixed with a commercially available tool such as a spanner.

Further, according to the present invention, as described in claim 2, since the tip portion has a fixing portion capable of fixing the screw member, a connecting member for connecting the tip portions is provided. Can be easily fixed by a screw member.

Further, in the present invention, as described in claim 3, since the fixing portion can fix the screw member along a direction intersecting the axis of the terminal, the connecting member is Even if the screw member is rotated for fixing, the terminal can be prevented from being rotated together with the screw member.

Further, in the present invention, as described in claim 4, since the distal end portion has the female screw portion with which the screw portion can be screwed, the screw member can be easily attached.

[0024]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of a battery according to the present invention will be described below in detail with reference to the drawings. As shown in FIG. 1, the sealed battery 50 according to the first embodiment of the present invention.
Is a lithium-ion battery configured in the same manner as the conventional sealed battery 10 (see FIG. 10) except for the positive electrode terminal 53 and the negative electrode terminal 54. That is, in this sealed battery 50, the power generation element 51 including the positive electrode and the negative electrode via the separator,
It is housed in the battery case (sealed battery exterior body) 52 through the opening 52a. A positive electrode terminal 53 is provided on the rear end side (upper side in the figure) of the power generating element 51 with respect to the housing direction of the power generating element 51.
The negative terminal 54 and the tip 72 (upper part in the figure) of the battery case
52 It is provided to be exposed to the outside.

In this sealed battery 50, an aluminum foil having a thickness of 20 μm is used as a positive electrode current collector, and a copper foil having a thickness of 14 μm is used as a negative electrode current collector. The positive electrode current collector and the negative electrode current collector are joined to the positive electrode current collector plate and the negative electrode current collector plate by laser welding, electric resistance welding, or the like.

A lid plate 62 is fitted in the opening 52a of the battery case 52. The lid plate 62 has through-holes 63 for inserting the tip portions 72 of the positive electrode terminal 53 and the negative electrode terminal 54, respectively.
It has on the 65, and has a rising portion 65a that is bent in a substantially L shape at the side end of the flat plate portion 65. And the lid plate 62
With the through-hole 63 in the positive terminal while the inside of the battery case 52 is closed.
It is configured to be exposed to the outside of the battery case 52 via the tip portion 72 of the negative electrode terminal 54 and 53.

The lid plate 62 is provided with a communication hole 65b, and a rupture valve 66 closing the communication hole 65b prevents an abnormal rise in the battery internal pressure.

As shown in FIG. 2, the positive electrode terminal 53 and the negative electrode terminal 54 have a collar portion 70 facing the back surface of the cover plate 62 and a cover plate 62.
A threaded portion 71 that is inserted into the insertion hole 63 and a tip portion 72 that is joined to the threaded portion 71 and projects toward the front surface side of the cover plate 62. Tip portions 72 of these positive electrode terminal 53 and negative electrode terminal 54
Has a substantially rectangular planar shape when viewed along the axial direction, and has a parallel width across flats on both sides of which the axis 73 of each terminal 53, 54 is sandwiched.
It has 74a and 74b.

Then, as shown in FIG. 3, packing is provided between the flange portions 70 of the positive electrode terminal 53 and the negative electrode terminal 54 and the flat plate portion 65 of the cover plate 62 so as to circulate on the base side of the screw portion 71. (O
Ring) 75 is arranged. A fixing nut 76 is screwed onto the screw portion 71 of the positive electrode terminal 53 and the negative electrode terminal 54 at a portion of the lid plate 62 protruding from the flat plate portion 65. As a result, the flange portions 70 of the positive electrode terminal 53 and the negative electrode terminal 54 are biased by the flat plate portion 65 with a predetermined force, and the packing 75 is pressed with a predetermined force.

As described above, the sealed battery 50 of the first embodiment.
According to this, the tip 72 has a width across flat 74a substantially parallel to the axis 73 of the positive electrode terminal 53 and the negative electrode terminal 54 so that the planar shape of the tip 72 viewed along the axial direction is not a perfect circle. ， 74
Since b is provided, when fixing the positive electrode terminal 53 and the negative electrode terminal 54 to the cover plate 62 with the fixing nut 76, by fixing the width across flats 74a and 74b with a spanner or the like, the positive electrode terminal 53 and the negative electrode terminal 54 are fixed. 54 can be prevented from rotating together with the fixing nut 76. Therefore, according to the sealed battery 50, it is possible to prevent the positive electrode current collector and the negative electrode current collector from being torn from the positive electrode current collector plate and the negative electrode current collector plate, respectively.

In particular, according to the sealed battery 50, the positive electrode current collector is made for the positive electrode current collector made of aluminum foil having a thickness of 20 μm and the negative electrode current collector made of copper foil having a thickness of 14 μm. Since it is a lithium-ion battery in which a plate and a negative electrode current collector plate are joined, the positive terminal 53 and the negative terminal 54 are fixed nuts 76.
It is possible to very effectively prevent the positive electrode current collector and the negative electrode current collector from being torn from the positive electrode current collector plate and the negative electrode current collector plate by preventing them from circling together. In addition to the lithium-ion battery, such an effect is obtained when the thickness dimension is 10
It is effective for all sealed batteries that employ an extremely thin current collector of μm to 50 μm.

Furthermore, according to this sealed battery 50, the planar shape of the tip portion 72 as viewed along the axial direction is a dihedral width 74.
Since it has a and 74b, the positive electrode terminal 53 and the negative electrode terminal 54 can be fixed by a commercially available tool such as a spanner.

Further, since the positive electrode terminal 53 and the negative electrode terminal 54 are fixed to the cover plate 62 with a predetermined tightening strength, the packing 75
Is sufficiently pressurized so that the flange portions 70 of the positive electrode terminal 53 and the negative electrode terminal 54 and the flat plate portion 65 of the cover plate 62 are reliably sealed, and
The airtightness inside 52 can be maintained.

In the first embodiment described above, the tip portion 72 having a substantially rectangular cross section is provided above the screw portions 71 of the positive electrode terminal 53 and the negative electrode terminal 54. However, as shown in FIG.
It is also possible to provide the width across flats 77a and 77b by lengthening 71 and processing the side surfaces of the upper portion thereof in parallel.

FIG. 5 shows a positive electrode terminal 80 and a negative electrode terminal 81 of the second embodiment according to the present invention. The positive electrode terminal 80 and the negative electrode terminal 81 are the same as the positive electrode terminal 53 and the negative electrode terminal 54 of FIG. The tip portions 82 of the positive electrode terminal 80 and the negative electrode terminal 81 are formed to have a substantially square cross section, parallel side widths 83a and 83b are provided on the side surfaces, and the sealed battery 50 is connected to the upper surfaces thereof. The female screw portion 86 is provided as a fixing portion for fixing the screw member 85 for attaching the connecting member 84.

Then, the long connecting member 84 is placed on the upper surface of the tip end portion 82, and the screw member 85 is screwed into the female screw portion 86 through the bolt hole 87 of the connecting member 84, thereby connecting the connecting member 84.
Can be fixed. The positive electrode terminal 80 and the negative electrode terminal 81 can securely fix the connecting member 84. Also,
Since the screw member 85 is screwed in from the upper side, the screwing operation becomes easy. At this time, by fixing the width across flats 83a, 83b with a spanner or the like, the positive terminal 80 and the negative terminal are fixed.
It is possible to prevent the 81 from rotating together with the screw member 85.

FIG. 6 shows a positive electrode terminal 90 and a negative electrode terminal 91 of the third embodiment according to the present invention. These terminals 90, 91
2 is the same as the positive electrode terminal 53 and the negative electrode terminal 54 of FIG. The tip portions 92 of the positive electrode terminal 90 and the negative electrode terminal 91 are formed in a substantially rectangular cross section, and have parallel widths 93a and 93b on both sides. Also, width across flats 93
Through holes 96 are provided on the plate surfaces of a and 93b as fixing portions for fixing screw members 95 for attaching the connecting members 94.

The through hole 96 is formed by connecting the screw member 95 to the positive electrode terminal 90.
The holes are provided so that they can be fixed along a direction intersecting the axis 73 of the negative electrode terminal 91, in the present embodiment, a direction substantially orthogonal to the axis 73. When attaching the connecting member 94, attach the connecting member 94 to one side 93a of the width across flats 93a, 93b.
The bolt hole 97 of the connecting member 94 and the through hole of the tip portion 92.
Insert the screw member 95 into 96 and connect the nut to the screw member 95.
The tip portion 92 and the connecting member 94 are fastened and fixed by screwing 98. The positive electrode terminal 90 and the negative electrode terminal 91 can also securely fix the connecting member 94.

As shown in FIG. 7, a female screw portion 99, which is a fixing portion, can be provided in the tip portion 92 in place of the through hole 96 described above. In this case, since the connecting member 94 can be fixed only by screwing the screw member 95 into the female screw portion 99 without using the connecting nut 98, it is possible to save the labor for mounting.

Further, in this case, the rotation direction when the screw member 95 is screwed in is the direction intersecting the axis 73, that is, the screwing direction of the screw member 95 and the terminals 90, 91.
Since the direction of rotation when the fixing nut 76 (FIG. 1) is screwed into the threaded portion 71 intersects, the positive electrode terminal 90 and the negative electrode terminal 91 can be prevented from rotating when the screw member 95 is screwed in.

In addition, the power generation element, the current collector, the terminal, the battery case, the cover plate, the collar portion, the insertion hole, the screw portion, the tip portion, the fixing nut, the fixing portion, the female screw portion, etc., which are exemplified in the above-mentioned respective embodiments. The material, shape, size, form, number, location, etc. are arbitrary and are not limited as long as the present invention can be achieved.

[0042]

As described above, according to the battery of the present invention, as described in claim 1, the tip end portion has a plane shape other than a perfect circle as seen along the axial direction, and therefore the tip end is previously formed. If a terminal is fixed by engaging a dedicated tool having an opening corresponding to the planar shape of each part, it is possible to prevent each terminal from co-rotating with the fixing nut, and thus, the positive electrode current collector plate and the negative electrode current collector plate. Therefore, the conventional problem that the positive electrode current collector and the negative electrode current collector are broken can be avoided. Such an effect is effective for a sealed battery such as a lithium-ion battery whose collector is extremely thin.

Further, according to the battery of the present invention, as described in claim 2, when the tip portion is provided with the fixing portion capable of fixing the screw member, the connecting member for connecting the tip portion is provided with the screw member. By securely fixing, the batteries can be reliably connected to each other.

Further, according to the battery of the present invention, the battery according to claim 3
As described in, when the fixing portion can fix the screw member in the direction intersecting with the axis of the terminal, when the screw member is screwed in to fix the connecting member, the terminal has the screw member. It can be prevented from going around with.

According to the battery of the present invention, the method according to claim 4
As described above, in the case where the fixing portion is provided with the female screw portion into which the screw member is screwed, the screw member can be easily attached, so that the labor of attachment can be saved.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a sealed battery according to a first embodiment of the present invention.

FIG. 2 is a perspective view showing a positive electrode terminal and a negative electrode terminal according to the first embodiment of the present invention.

FIG. 3 is a cross-sectional view showing an attached state of the positive electrode terminal and the negative electrode terminal according to the first embodiment of the present invention.

FIG. 4 is a perspective view showing another example of the first exemplary embodiment of the present invention.

FIG. 5 is a perspective view showing a positive electrode terminal and a negative electrode terminal according to a second embodiment of the present invention.

FIG. 6 is a perspective view showing a positive electrode terminal and a negative electrode terminal according to a third embodiment of the present invention.

FIG. 7 is a perspective view showing another example of the third exemplary embodiment of the present invention.

FIG. 8 is an exploded perspective view showing a conventional sealed battery.

FIG. 9 is a perspective view and a cross-sectional view showing a main part of a conventional sealed battery.

FIG. 10 is a cross-sectional view of a conventional sealed battery.

11 is a cross-sectional view taken along the line AA of FIG.

[Explanation of symbols]

50 sealed batteries 51 Power generation element 52 Battery case 53, 80, 90 Positive terminal 54, 81, 91 negative terminal 62 Lid plate 70 Tsuba 71 Thread 72, 82, 92 Tip 73 axis 74a, 74b, 83a, 83b, 93a, 93b width across flats 76 fixing nut 85, 95 screw member 86,99 Female thread (fixed part) 96 through holes (fixed part)

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Tetsuo Ono             2-32 Kosobe-cho, Takatsuki City, Osaka Prefecture Stock             Ceremony company Yuasa Corporation F term (reference) 5H022 AA04 AA09 BB03 CC03                 5H029 AJ11 AJ14 DJ02 DJ05 DJ07

Claims (4)

[Claims] 1. A power generating element having a negative electrode and a positive electrode with a separator interposed therebetween, a current collector plate connected to end edges of the negative electrode and the positive electrode in a plane direction, and the power generating element bonded to each current collector plate. A pair of terminals extending in a direction away from each other, a battery case accommodating the power generation element, and a cover plate that penetrates the terminals and seals the battery case, and the terminal is the cover plate. A flange portion facing the back surface of the lid plate, a screw portion to be inserted into the insertion hole of the lid plate, and a tip portion integrated with the screw portion and protruding to the front surface side of the lid plate, and the screw A battery in which the terminal is fixed to the cover plate by screwing a fixing nut to the portion, wherein the planar shape of the tip portion viewed along the axial direction is other than a perfect circle. . 2. The battery according to claim 1, wherein the tip portion has a fixing portion to which a screw member can be fixed. 3. The battery according to claim 2, wherein the fixing portion can fix the screw member along a direction intersecting an axis of the terminal. 4. The battery according to claim 2, wherein the tip portion has a female screw portion into which the screw portion can be screwed.