JP2008243811A - Battery - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a battery having small direct current resistance and superior current collection performance. <P>SOLUTION: The battery has a case 8 with a bottom storing a group of electrode plates 4 wherein a beltlike positive electrode plate 1 and a beltlike negative electrode plate 2 are laminated or spirally wound via a separator 3 and an electrolyte in its inside and also serving as one external terminal, a sealing-up body 10 tightly shutting up an opening at an upper end of the case 8 with a bottom by caulking sealing-up, and also serving as the other external terminal, and a connection terminal 7 for electrically connecting the sealing-up body 10 and an upper current collector 5 wherein one electrode plate of the group of electrode plates 4 is welded. A part of the outer periphery of the connection terminal 7 and a part of the sealing-up body 10 are electrically connected by caulking sealing-up. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a battery having a novel current collecting structure capable of achieving high output.

  Batteries such as alkaline storage batteries and lithium ion secondary batteries are widely used as power sources for portable devices, electric tools, or electric vehicles. Above all, the use of nickel-metal hydride storage batteries, which have a relatively high energy density and excellent durability, is expanding mainly in power sources for electric vehicles.

  Nickel metal hydride storage batteries house a group of electrode plates wound in a spiral shape with a separator interposed between a strip-shaped positive electrode plate and a negative electrode plate in a metal bottomed case that also serves as one external terminal, The opening of the bottomed case made of the product is configured to be sealed by a sealing body that also serves as the other external terminal.

  As the input / output current collecting structure from the electrode plate group suitable for large current discharge, one side edge along the longitudinal direction of the positive electrode plate protrudes above the electrode plate group, and the above-mentioned along the longitudinal direction of the negative electrode plate. The electrode plate group is configured such that the side edge portion opposite to the one side edge portion protrudes downward from the electrode plate group, and each of the protruding portions has a rectangular or substantially disc-shaped upper current collector and lower current collector. Generally, a method is used in which an electric body is welded, a tab terminal is resistance-welded to the upper surface of the upper current collector, and the other end of the tab terminal is resistance-welded to the lower surface of the sealing body.

  FIG. 8 is a schematic sectional view showing the configuration of a conventional cylindrical storage battery.

  A separator 13 is interposed between the strip-like positive electrode plate 11 and the negative electrode plate 12 and is wound in a spiral shape to constitute an electrode plate group 14. The lower current collector 16 is welded to the side edge portion 12a of the negative electrode plate protruding downward from the electrode plate group 14, and the tab terminal 17 is previously welded to the side edge portion 11a of the positive electrode plate protruding above the electrode plate group 14. The upper current collector 15 is welded.

  Next, the electrode plate group 14 in which the upper current collector 15 and the lower current collector 16 are welded is housed in a metal bottomed case 18, and the lower current collector 16 is placed on the bottom inner surface of the metal bottomed case 18. Weld. An insulating ring 19 is disposed on the upper surface of the upper current collector 15, and a groove 18 a is formed to hold the electrode plate group 14 in a metal bottomed case 18. Above the tab terminal 17, the sealing body 20 provided with the cover plate 20a, the rubber valve body 20b, the cap 20c, and the gasket 20d is welded.

  Thereafter, the electrolytic solution is injected into the bottomed case 18 from the liquid injection port 15 a provided in the upper current collector 15, and the sealing body 20 is disposed in the opening of the metal bottomed case 18 while bending the tab terminal 17. The cylindrical storage battery is manufactured by sealing this opening with a caulking seal.

  When used for an application that requires a large current discharge, it is necessary to efficiently extract current from the electrode plate group 14, so that it is required to reduce the DC resistance of the upper current collector 15, the lower current collector 16, and the tab terminal 17. .

  In order to reduce these DC resistances, for example, it is desirable that the tab terminal 17 be as short as possible. However, when the sealing body 20 is welded to the other end of the tab terminal 17 welded to the upper current collector 15, at least. About half the outer diameter of the sealing body 20 is required. Moreover, in order to further shorten the length of the tab terminal 17, a special construction method or a welding method is required, and various methods have been proposed.

  For example, a method has been proposed in which the lower surface of the sealing body is directly joined to the side edge portion of the positive electrode plate protruding above the electrode plate group without using the tab terminal.

  FIG. 9 is a schematic cross-sectional view showing the configuration of a cylindrical storage battery manufactured without using a tab terminal.

  A separator 23 is interposed between the strip-like positive electrode plate 21 and the negative electrode plate 22 and wound in a spiral shape to constitute an electrode plate group 24. The lower current collector 26 is welded to the side edge portion 22a of the negative electrode plate protruding downward from the electrode plate group 24, and the upper current collector 25 is welded to the side edge portion 21a of the positive electrode plate protruding above the electrode plate group 24. To do.

  Next, the electrode plate group 24 in which the upper current collector 25 and the lower current collector 26 are welded is housed in a metal bottomed case 28, and the lower current collector 26 is placed on the bottom inner surface of the metal bottomed case 28. After the welding, the lid plate 30a of the sealing body 30 and the insulating ring 29 are arranged on the upper surface of the upper current collector 25, and the groove portion 28a is formed. Then, the gasket 30d is placed on the upper portion of the groove portion 28a and the lid plate 30a The upper current collector 25 is welded, and the opening of the bottomed case 28 made of metal is caulked inward. The electrolyte is injected into the bottomed case 28 from the liquid inlet provided in the center of the lid plate 30a and the liquid inlet 25a provided in the upper current collector 25, and the rubber valve body 30b and the cap 30c are injected into the lid plate 30a. And a cap 30c is welded to the lid plate 30a to produce a cylindrical storage battery.

Thus, a cylindrical storage battery is obtained by directly joining the lower surface of the sealing body 30 to the side edge portion 21a of the positive electrode plate or the upper current collector 25 protruding above the electrode plate group 24 without using the tab terminal. Has been proposed (see, for example, Patent Document 1).
JP 2000-243433 A

  However, the method of directly joining the lower surface of the sealing body to the side edge of the positive electrode plate protruding above the electrode group or the upper current collector without using such a tab terminal is to irradiate laser from above the sealing body. There is a risk that the electrolyte may leak due to a hole in the sealing body. When welding was performed with a low laser output in order to prevent this hole opening, welding was insufficient and there was a risk that the DC resistance would increase.

  The present invention solves the above-mentioned problem, and by electrically connecting a part of the outer peripheral portion of the connection terminal for electrically connecting the sealing body and the upper current collector and a part of the sealing body by caulking and sealing. An object of the present invention is to provide a battery that does not leak from the sealing body, has a low direct current resistance, and has excellent current collecting performance from the electrode plate group.

  In order to solve the above-described problems, the present invention provides an external terminal in which a group of electrode plates formed by laminating a band-like positive electrode plate and a negative electrode plate via a separator or spirally wound therein and an electrolyte are housed inside A bottomed case that also serves as a sealing member, a sealing body that also serves as the other external terminal that seals the opening at the upper end of the bottomed case with a caulking seal, and welds the sealing body and one electrode plate of the electrode plate group A battery provided with a connection terminal for electrically connecting the upper current collector, wherein a part of the outer peripheral portion of the connection terminal and a part of the sealing body are electrically connected by caulking and sealing. .

  With this configuration, it is possible to easily produce a battery that does not leak from the sealing body, has a low direct current resistance, and has excellent current collecting performance from the electrode plate group.

  According to the present invention, since a part of the outer peripheral portion of the connection terminal that electrically connects the sealing body and the upper current collector and the part of the sealing body are electrically connected by caulking, liquid leakage from the sealing body Thus, an effect of providing a battery having a small direct current resistance and excellent current collecting performance from the electrode plate group by an easy method is obtained.

  In the present invention, a bottomed case that also serves as one external terminal containing a plate group formed by laminating a band-like positive electrode plate and a negative electrode plate via a separator or spirally wound therein and an electrolyte solution therein A sealing body that also serves as the other external terminal that seals the opening at the upper end of the bottomed case by caulking, and an upper current collector welded to the sealing body and one electrode plate of the electrode plate group. A battery provided with a connection terminal for electrical connection, wherein a part of the outer peripheral portion of the connection terminal and a part of the sealing body are electrically connected by caulking and sealing.

  According to this configuration, since the sealing body and the connection terminal are electrically joined by caulking sealing, it is not necessary to weld from above the sealing body. For this reason, there is no possibility that the sealing body has a hole and the electrolyte solution leaks. In addition, since the connection terminal and one electrode plate of the electrode plate group are welded in a state before sealing, the connection terminal and the sealing body can be electrically connected to the sealing body with a short connection terminal without welding. A battery having low resistance and excellent current collecting performance from the electrode plate group can be easily produced.

  Further, it is desirable that a plurality of tongue pieces are provided in a connecting portion that constitutes the outer peripheral portion of the connection terminal, and provided with a plurality of tongue pieces that are radially bent and bent downward.

  According to this configuration, when the connection terminal and the upper current collector are welded, even if the height of the upper current collector is different due to the difference in height of the electrode plate group, the bent portion of the tongue piece is deformed. The effect that the welding is stabilized is obtained by bending the straight portion in the height direction of the tongue piece bent downward. Further, even when vibration or impact is applied to the battery after welding, the plurality of tongue pieces bent downward have an effect of absorbing and mitigating the vibration and impact.

  Further, it is desirable that a flange projecting outward is provided at the opening of the upper end portion of the bottomed case, and the sealing body installed on the collar is caulked and sealed with a bent portion at the peripheral edge of the collar.

  According to this configuration, since it is not necessary to provide the groove portion in the bottomed case, the connection terminal does not need to be long enough to compensate for the height dimension of the groove portion, and can be shortened. Since a short connection terminal can be configured in this way, an effect of reducing the DC resistance can be obtained.

  Moreover, the structure which provided 2-6 tongue pieces is desirable.

  According to this configuration, it is possible to obtain an effect on the process that the number of weldings is small and welding can be performed in a short time, and an effect on the battery characteristics that the direct current resistance can be reduced.

  Moreover, the structure which provided the protrusion along the outer peripheral part of a connection terminal in the front-end | tip part of a tongue piece is desirable.

  According to this configuration, the projecting piece can flexibly cope with variations in the height direction of the electrode plate group. As a result, the contact with the upper current collector is improved, welding is stabilized, and the effect of further reducing the DC resistance can be obtained.

  The configuration of the cylindrical storage battery of the present invention will be described below with reference to the drawings.

FIG. 3A is a perspective view showing the configuration of the electrode plate group used in the cylindrical storage battery of the present invention, and FIG.
The perspective view which showed the structure of the electrode group used for the cylindrical storage battery of this invention, the upper collector, and the lower collector is shown.

  As shown in FIG. 3 (a), a belt-like sintered positive electrode plate 1 having a positive electrode plate side edge portion 1a at the end portion and a negative electrode plate side edge portion 2a at the end portion. Then, a negative electrode plate 2 is formed by coating a negative electrode active material mainly composed of a hydrogen storage alloy on a nickel plating punched steel sheet. The positive electrode plate 1 and the negative electrode plate 2 are spirally wound so as to protrude from the separator 3 in a direction in which the side edge portion 1a of the positive electrode plate and the side edge portion 2a of the negative electrode plate are opposed to each other, thereby forming the electrode plate group 4. . As shown in FIG. 3B, the upper current collector 5 provided with a liquid injection port 5a is welded to the side edge 1a of the positive electrode plate protruding upward from the electrode plate group 4, and the negative electrode plate protruding downward The lower current collector 6 is welded to the side edge 2a.

  4A to 4E are explanatory views showing the assembly process of the cylindrical storage battery of the present invention. FIG. 4A is an explanatory view showing the electrode plate group insertion process of the cylindrical storage battery of the present invention, FIG. 4B is an explanatory view showing the gasket insertion process of the cylindrical storage battery of the present invention, and FIG. ) Is an explanatory view showing the connecting terminal welding process of the cylindrical storage battery of the present invention, FIG. 4 (d) is an explanatory view showing the sealing body installation process of the cylindrical storage battery of the present invention, and FIG. 4 (e) is the present invention. It is explanatory drawing which showed the crimping process of the cylindrical storage battery of this.

  As shown in FIG. 4A, the electrode plate group 4 in which the upper current collector 5 and the lower current collector 6 are welded to the side edge portion 1a of the positive electrode plate and the side edge portion 2a of the negative electrode plate, respectively, is prevented from short circuit. It is housed in a metal bottomed case 8 together with an insulating ring 9 for welding, and the lower current collector 6 and the bottom inner surface of the metal bottomed case 8 are welded.

  Next, as shown in FIG. 4B, after the groove 8a is formed, the gasket 10d is placed on the support 8b.

  FIG. 6 is a perspective view showing an example of the connection terminal of the present invention. As shown in FIG. 6, four tongue pieces 7 b are provided in the connecting portion 7 a constituting the outer peripheral portion of the connection terminal 7, the tip portions protruding radially inward and bent downward.

  As shown in FIG. 4C, the connection terminal 7 is installed on the upper current collector 5, and the tongue piece 7 b of the connection terminal 7 and the upper current collector 5 are welded.

  After the alkaline electrolyte mainly composed of potassium hydroxide is injected into the bottomed case 8 from the injection port 5a provided in the upper current collector 5, as shown in FIG. 4 (d), the opening of the bottomed case 8 is opened. The sealing body 10 provided with the cover plate 10a, the rubber valve body 10b, the cap 10c, and the gasket 10d is installed in the part.

  Next, as shown in FIG. 4E, the upper part of the bottomed case 8 made of metal is caulked inward to fix the cover plate 10a, and the battery is sealed, and the outer peripheral portion of the cover plate 10a The connecting portion 7a constituting the outer peripheral portion of the connection terminal 7 is pressed and electrically connected.

  A battery can be easily assembled by assembling a battery by the above methods.

  Further, when the tongue 7b of the connection terminal 7 and the upper current collector 5 are welded, the height dimension of the electrode plate group 4 can be changed by changing the angle of the portion bent downward of the tongue 7b of the connection terminal 7. An effect of absorbing variation can be obtained.

The angle of the portion of the connecting terminal 7 that is bent below the tongue piece 7b is such that the tongue piece 7b and the upper insulator 5 are angled.
Therefore, the tongue piece 7b and the upper current collector 5 can be easily aligned in the height direction. As a result, the tongue piece 7b and the upper current collector can be easily aligned. Therefore, the connection terminal 7 and the upper current collector 5 can be stably welded.

  Moreover, you may provide the bending part which can be bent in a height direction in the intermediate part bent below the connection part 7a and the tongue piece 7b which comprise the outer peripheral part of the connecting terminal 7. FIG. For example, a loosely bent portion can be easily manufactured. If such a bent portion is provided, the portion bent downward of the tongue piece 7b can more effectively absorb the variation in the dimension of the electrode plate group 4 in the height direction.

  Further, since the welded portion between the tongue piece 7b of the connection terminal 7 and the upper current collector 5 is inside the battery, even if a blowhole occurs, it does not cause liquid leakage.

  Moreover, the sealing body 10 is installed in the annular support part 8b formed in the upper-end opening part of the bottomed case 8, and it crimps and seals and the connection part 7a of the connection terminal 7 and the sealing body 10 are electrically connected. A battery having a short connection terminal 7 can be manufactured by an easy method.

  FIGS. 5A to 5E are explanatory views showing an assembly process of a cylindrical storage battery having another configuration of the present invention. FIG. 5A is an explanatory view showing an electrode plate group insertion step of a cylindrical storage battery of another configuration of the present invention, and FIG. 5B shows a gasket insertion step of a cylindrical storage battery of another configuration of the present invention. FIG. 5 (c) is an explanatory view showing a connecting terminal welding process of a cylindrical storage battery of another configuration of the present invention, and FIG. 5 (d) is a sealing body of a cylindrical storage battery of another configuration of the present invention. FIG. 5E is an explanatory view showing an installation process, and FIG. 5E is an explanatory view showing a caulking process of a cylindrical storage battery having another configuration of the present invention.

  As the bottomed case 8, the opening portion is preliminarily widened to provide the flange portion 8 c, the groove portion is not formed, and the connecting terminal 7 is connected to the connecting portion 7 a constituting the outer peripheral portion of the connecting terminal 7 as shown in FIG. 7. Provided are four tongue pieces 7b that are provided in the radial direction and projecting inwardly at the tip portion that protrudes inward, and the height of the tongue piece 7b that is bent downward is short. The assembly process is the same as that shown in FIGS. 4A to 4E except for use.

  In the assembly process shown in FIGS. 4A to 4E, since the groove portion 8a is formed in the bottomed case 8, a space corresponding to the height of the groove portion 8a is provided between the upper portion of the electrode plate group 4 and the sealing body 10. However, according to the assembly process shown in FIGS. 5A to 5E, it is not necessary to produce the groove 8a. An effect of shortening the length can be obtained.

  Next, the connection terminals shown in FIGS. 10 and 11 will be described. The connection terminal 7 shown in FIGS. 10 and 11 is provided with a projecting piece 7 c in which the tip of the tongue piece 7 b extends along the outer peripheral portion of the connection terminal 7. Thereby, according to the height of the electrode plate group 4, the position of the tongue piece 7b welded to the upper collector 5 can be set to an arbitrary position of the protruding piece 7c.

  When the height of the electrode plate group 4 is low, the amount of displacement in the height direction of the tongue piece 7 can be increased by welding to the projecting piece 7c, so that it can be easily welded. At this time, the amount of displacement of the tongue piece 7 in the height direction can be increased as the protrusion 7c is welded to the tip.

  Further, when the height of the electrode plate group 4 is relatively high, the direct current resistance can be further reduced by welding at the base portion of the tongue piece 7b close to the connecting portion 7a. In this way, when the protruding piece 7c in which the tip of the tongue piece 7b of the connection terminal 7 extends along the outer peripheral portion is provided, it is connected to a fixed position on the upper current collector 5 according to the height of the electrode plate group 4. Since welding can be performed at an arbitrary position of the tongue piece 7b including the protruding piece 7c of the terminal 7, it is possible to cope with a large height variation such as a variation in the height direction of the electrode plate group 4.

  Next, the connection terminals shown in FIGS. 12 and 13 will be described. The connection terminal 7 shown in FIGS. 12 and 13 is provided with one tongue piece 7b. According to this configuration, since the number of weldings between the connection terminal 7 and the upper current collector 5 can be performed once, the connection terminal welding process can be performed in a short time.

  Next, the connection terminals shown in FIGS. 14 and 15 will be described. The connection terminal 7 shown in FIGS. 14 and 15 is provided with two tongue pieces 7b. According to this configuration, the number of weldings between the connection terminal 7 and the upper current collector 5 can be reduced, and welding can be performed at two locations.

  Next, the connection terminals shown in FIGS. 16 and 17 will be described. The connection terminal 7 shown in FIGS. 16 and 17 is provided with six tongue pieces 7b. Thus, when there are many tongue pieces 7b, a cylindrical storage battery with small direct-current resistance can be produced.

  When the number of the tongue pieces 7b is reduced, the number of weldings is reduced and the interval between the welded portions is widened, so that welding in the connection terminal welding process is stabilized and the cylindrical storage battery can be easily manufactured. If the number of tongue pieces 7b is 6 or less, welding is sufficiently stabilized. If the number of tongue pieces 7b is increased, the direct current resistance can be reduced. However, if the number of tongue pieces 7b is two or more, the direct current resistance can be sufficiently reduced. Therefore, it is particularly preferable to reduce the number of tongue pieces 7b from 2 to 6 because a cylindrical storage battery having a low DC resistance can be produced with a small number of weldings.

  A method for producing the cylindrical nickel-metal hydride storage battery of the present invention will be described.

  Nickel powder, methylcellulose, and water were kneaded to form a paste, applied to a nickel-plated punching metal core, dried and sintered to obtain a sintered positive electrode substrate. This positive electrode substrate was alternately impregnated with an aqueous solution mainly composed of nickel nitrate and an alkaline aqueous solution mainly composed of sodium hydroxide, and was filled with nickel hydroxide. This was dried and then cut to prepare a sintered positive electrode plate 1 having a length of 550 mm, a width of 48.5 mm, and a thickness of 0.32 mm. In addition, the part which does not apply a paste at the time of preparation of a sintering type positive electrode substrate was provided, and it was set as the side edge part 1a of a positive electrode plate.

  Next, the hydrogen storage alloy was kneaded with carbon, a carboxymethyl cellulose aqueous solution, and a styrene butadiene copolymer dispersion to obtain a hydrogen storage alloy paste. This was coated on a nickel-plated punching metal, dried, rolled and cut to obtain a hydrogen storage alloy negative electrode plate 2 having a length of 600 mm, a width of 48.5 mm, and a thickness of 0.24 mm. In addition, the part which does not apply a hydrogen storage alloy paste at the time of the application of the negative electrode plate 2 of a hydrogen storage alloy was provided, and it was set as the side edge 2a of the negative electrode plate.

  As the separator 3, a polypropylene nonwoven fabric having a width of 50 mm, a length of 1200 mm, and a thickness of 0.20 mm subjected to hydrophilic treatment was used.

  The positive electrode plate 1 and the negative electrode plate 2 produced as described above are swirled so that the side edge portion 1a of the positive electrode plate and the side edge portion 2a of the negative electrode plate protrude from the separator 3 through the separator 3 made of polypropylene nonwoven fabric. The electrode plate group 4 having a diameter of about 30.5 mm and a height of about 51.5 mm was produced.

  FIG. 1 is a schematic cross-sectional view showing the configuration of a cylindrical storage battery of Example 1, FIGS. 4A to 4E are explanatory diagrams showing an assembly process of the cylindrical storage battery of Example 1, and FIG. It is the perspective view which showed 1 connection terminal.

An upper current collector 5 made of nickel-plated low carbon steel having a thickness of 0.50 mm is welded to the side edge 1a of the positive electrode plate protruding above the electrode plate group 4, and the side edge of the negative electrode plate protruding downward A lower current collector 6 having a thickness of 0.45 mm made of low carbon steel plated with nickel on 2a was resistance welded. As shown in FIG. 4 (a), the electrode plate group 4 in which the upper current collector 5 and the lower current collector 6 are resistance-welded is made of a nickel-plated steel plate together with an insulating ring 9 made of nylon resin for preventing a short circuit. The bottom current collector 6 and the bottom inner surface of the bottomed case 8 were resistance welded. Next, as shown in FIG. 4B, while rotating the bottomed case 8, a disk-shaped jig is pressed from the outside to form a groove 8 a at a position above the electrode plate group 4, and then nylon A resin gasket 10d was installed. Further, as shown in FIG. 4C, after the connection terminal 7 made of nickel having a thickness of 0.40 mm was installed, the tongue piece 7b of the connection terminal 7 and the upper current collector 5 were resistance-welded. Next, an alkaline electrolyte mainly composed of potassium hydroxide is injected into the bottomed case 8 through the liquid injection port 5a provided in the upper current collector 5, and as shown in FIG. A sealing body 10 provided with a cover plate 10a, a rubber valve body 10b, a cap 10c, and a gasket 10d was installed in the opening. Next, as shown in FIG. 4E, the upper portion of the bottomed case 8 is caulked inward to fix the cover plate 10a, and the cover plate 10a and the connecting portion 7a constituting the outer peripheral portion of the connection terminal 7 are brought into pressure contact with each other. While electrically conducting, the cylindrical storage battery was sealed.

  As shown in FIG. 6, the connecting terminal 7 includes four tongue pieces 7b that are provided radially in the connecting portion 7a that constitutes the outer peripheral portion of the connecting terminal 7 and whose tip protruding inward is bent downward. The provided one was used.

  In addition, welding of the tongue piece 7b of the connection terminal 7 and the upper current collector 5 includes four tongue pieces 7b and a flat portion between four cuts provided in the radial direction of the upper current collector 5. Each was resistance welded. Since one resistance welding was performed by two-point welding, the total number of welding points is eight.

  The cylindrical nickel-metal hydride storage battery thus produced was designated as battery A of Example 1.

  FIG. 2 is a schematic cross-sectional view showing the configuration of the cylindrical storage battery of Example 2, FIGS. 5A to 5E are explanatory diagrams showing the assembly process of the cylindrical storage battery of Example 2, and FIG. It is the perspective view which showed 2 connection terminals.

  As shown in FIGS. 5A to 5E, as the bottomed case 8, the opening portion is preliminarily widened to provide the flange portion 8 c, the groove portion is not formed, and the connection terminal 7 is as shown in FIG. 7. A cylindrical nickel-metal hydride storage battery manufactured in the same manner as in Example 1 except that a tongue piece 7b having a short shape was used as Battery B of Example 2.

  As shown in FIG. 10, as the connection terminal 7, a cylindrical nickel produced in the same manner as in Example 1 except that the tip of the tongue piece 7b is provided with a protruding piece 7c along the outer periphery of the connection terminal 7. The hydrogen storage battery was designated as battery C of Example 3.

  As shown in FIG. 11, as the connection terminal 7, a bottomed case 8 provided with a flange portion 8c is used except that a tip piece of a tongue piece 7b is provided with a projecting piece 7c along the outer periphery of the connection terminal 7. A cylindrical nickel-metal hydride storage battery produced in the same manner as in Example 2 was used as Battery D of Example 4.

  In Examples 3 and 4, welding was performed at a substantially central position between the root portion of the tongue piece 7b close to the connecting portion 7a of the tongue piece 7b and the tip portion of the protruding piece 7c of the tongue piece 7b.

  A cylindrical nickel-metal hydride storage battery produced in the same manner as in Example 1 was used as the battery E of Example 5 except that a connection terminal 7 having one tongue piece 7b was used as shown in FIG.

  As shown in FIG. 13, as the connection terminal 7, a cylindrical type produced in the same manner as in Example 2 using the bottomed case 8 provided with the flange 8c except that one provided with one tongue piece 7b was used. The nickel metal hydride storage battery was designated as battery F of Example 6.

  In Examples 7 and 8, since the width of the tongue piece 7b was wide, two-point welding was performed so as to straddle any one notch among the four notches in the upper current collector 5.

  As shown in FIG. 14, the cylindrical nickel-metal hydride storage battery produced in the same manner as in Example 1 was used as the battery G of Example 7, except that a connection terminal 7 having two tongue pieces 7 b was used.

  As shown in FIG. 15, as the connection terminal 7, a cylindrical type manufactured in the same manner as in Example 2 using the bottomed case 8 provided with the flange 8 c except that one provided with two tongue pieces 7 b was used. The nickel metal hydride storage battery was designated as battery H of Example 8.

  In the seventh and eighth embodiments, the width of the tongue piece 7b is wide as in the fifth and sixth embodiments. Therefore, any two opposite cuts among the four cuts of the upper current collector 5 can be obtained by using the tongue piece 7b. Two points were welded to each other. Therefore, there are a total of four welding points.

  As shown in FIG. 16, the connection terminal 7 is the same as in Example 1 except that six tongue pieces 7 b are used and the upper current collector 5 is provided with six cuts in the radial direction. The cylindrical nickel-metal hydride storage battery produced in Example 5 was designated as battery I of Example 9.

  As shown in FIG. 17, the connecting terminal 7 is provided with six tongue pieces 7 b, and the upper current collector 5 is provided with a notch provided with six notches in the radial direction. A cylindrical nickel-metal hydride storage battery produced in the same manner as in Example 2 using the provided bottomed case 8 was designated as Battery J in Example 10.

  In Examples 9 and 10, the six tongue pieces 7b and the flat portions between the six cuts provided in the radial direction of the upper current collector 5 were welded. Therefore, there are a total of 12 welding points.

  As shown in FIG. 18, a cylindrical nickel-metal hydride storage battery manufactured in the same manner as in Example 1 was used as the battery K of Example 11, except that a connection terminal 7 having eight tongue pieces 7 b was used.

  As shown in FIG. 19, as the connection terminal 7, a cylindrical type manufactured in the same manner as in Example 2 using the bottomed case 8 provided with the flange portion 8c except that one having 8 tongue pieces 7b was used. The nickel metal hydride storage battery was designated as the battery L of Example 12.

  In Examples 11 and 12, eight tongue pieces 7b and two tongue pieces 7b were welded to flat portions between four cuts provided in the radial direction of the upper current collector 5, respectively. Therefore, the total number of welding points is 16.

(Comparative Example 1)
FIG. 8 is a schematic cross-sectional view showing the configuration of the cylindrical storage battery of Comparative Example 1.

  An electrode plate group was prepared in the same manner as the battery A of Example 1, and as shown in FIG. 8, a conventional rectangular tab terminal 17 was used instead of the connection terminal, and the upper end of the tab terminal 17 and the sealing body 20 A cylindrical nickel-metal hydride storage battery produced in the same manner as in Example 1 except that the lower surface was electrically connected by laser welding was designated as Battery M of Comparative Example 1.

  For the batteries A to M produced in Examples 1 to 12 and Comparative Example 1 described above, a charge / discharge cycle of charging at 600 mA for 15 hours and then discharging at 6000 mA for 40 minutes was performed twice in a 25 ° C. atmosphere. The negative electrode plate was activated by storing for 3 days in an atmosphere of ° C. Furthermore, after discharging to 6000 mA to 1.0 V, a charge / discharge cycle of charging at 6000 mA for 66 minutes was repeated 10 times in a 25 ° C. atmosphere to activate the negative electrode plate.

<Evaluation of DC resistance>
Each battery was discharged to 1.0 V at 6000 mA and then charged at 600 mA for 5 hours. After each of these batteries was left for 30 minutes, the following charge / discharge cycle was performed in an atmosphere at 25 ° C.

First cycle: Discharge 6000 mA × 20 seconds, pause 5 minutes, charge 6000 mA × 20 seconds, pause 5 minutes Second cycle: Discharge 18000 mA × 20 seconds, pause 5 minutes, charge 18000 mA × 20 seconds, pause 5 minutes Third cycle: Discharge 36000 mA × 20 seconds, rest 5 minutes, charge 36000 mA × 20 seconds, rest 5 minutes Fourth cycle: discharge 60000 mA × 20 seconds, rest 5 minutes, charge 60000 mA × 20 seconds, rest 5 minutes Set current for these four discharges An approximate straight line was obtained from the voltage after 10 seconds by the method of least squares, and the slope thereof was defined as a DC resistance, which was used as a substitute value for output characteristics in HEV applications. The evaluation was performed for 3 cells, and the average value is shown in (Table 1).

  As shown in (Table 1), it was found that the battery A of Example 1 and the battery B of Example 2 using the connection terminal 7 of the present invention showed a DC resistance smaller than that of the battery M of Comparative Example 1.

  This is probably because the connection terminals 7 of the batteries A and B are shorter than the tab terminal 17 of the battery M, and the total width of the tongue 7b of the connection terminal 7 is wide, so that the DC resistance is reduced.

  Further, it was found that the direct current resistance of the battery B was smaller than that of the battery A.

  This is presumably because the battery B can shorten the connection terminal 7 by providing the bottom portion 8 with the flange portion 8c.

  Similarly, it was found that any of the batteries C to L exhibited a DC resistance smaller than that of the battery M of Comparative Example 1.

  This is probably because the connection terminals 7 of the batteries C to L are shorter than the tab terminal 17 of the battery M, and the total width of the tongue pieces 7b of the connection terminal 7 is wide, so that the DC resistance is reduced.

  In addition, when comparing battery A and battery B, battery C and battery D, battery E and battery F, battery G and battery H, battery I and battery J, battery K and battery L, battery B, battery D, and battery F, respectively. It was found that the direct current resistance was smaller in the battery H, the battery J, and the battery L. This is considered to be because the connection terminal 7 can be made shorter by providing the flange portion 8c in the bottomed case 8.

Also, the battery E (tongue piece 7b: 1 piece), battery G (tongue piece 7b: 2 pieces), battery A (tongue piece 7b: 4 pieces), battery I (tongue piece 7b: 6 pieces), battery of the present invention K (tongue piece 7b: 8 pieces) all show a direct current resistance smaller than that of the battery K of Comparative Example 1, and the batteries G, battery A, battery I, and battery K provided with two or more tongue pieces 7b are particularly direct current resistances. Was found to be smaller. This is presumably because the total width of the tongue piece 7b is increased by increasing the number of tongue pieces 7b of the connection terminal 7. Moreover, the battery E, the battery G, the battery A, and the battery I in which the number of tongue pieces 7b is 6 or less were sufficiently small in the number of times of welding in the connection terminal welding process, and could be welded in a short time. Therefore, it was found that the number of tongue pieces 7b is particularly preferably 2 to 6.

  Further, for the batteries C and D, since the tip 7b of the tongue piece 7b is provided with a protruding piece 7c extending along the outer peripheral portion, the electrode plate group can be easily changed by changing the welding position on the tongue piece 7b. It was found that the height of 4 could be accommodated.

  Since the battery according to the present invention can reduce the direct current resistance as compared with a conventional battery, it is useful for an apparatus that requires a large current discharge, such as an electric vehicle.

Schematic sectional view showing the configuration of the cylindrical storage battery of the present invention Schematic sectional view showing another configuration of the cylindrical storage battery of the present invention (A) The perspective view which showed the structure of the electrode group used for the cylindrical storage battery of this invention, (b) The structure of the electrode group used for the cylindrical storage battery of this invention, an upper collector, and a lower collector A perspective view showing (A) Explanatory drawing which showed the electrode plate group insertion process of the cylindrical storage battery of this invention, (b) Explanatory drawing which showed the gasket insertion process of the cylindrical storage battery of this invention, (c) of the cylindrical storage battery of this invention Explanatory drawing showing the connection terminal welding process, (d) Explanatory drawing showing the sealing body installation step of the cylindrical storage battery of the present invention, (e) Explanatory drawing showing the caulking process of the cylindrical storage battery of the present invention (A) Explanatory drawing which showed the electrode group insertion process of the cylindrical storage battery of the other structure of this invention, (b) Explanatory drawing which showed the gasket insertion process of the cylindrical storage battery of the other structure of this invention, (c) ) An explanatory diagram showing the connection terminal welding of a cylindrical storage battery of another configuration of the present invention, (d) an explanatory diagram showing installation of a sealing body of a cylindrical storage battery of another configuration of the present invention, (e) Explanatory drawing which showed the caulking process of the cylindrical storage battery of another structure The perspective view which showed the connecting terminal of Example 1 of this invention The perspective view which showed the connecting terminal of Example 2 of this invention Schematic sectional view showing the configuration of a conventional cylindrical storage battery Schematic sectional view showing another configuration of a conventional cylindrical battery The perspective view which showed the connecting terminal of Example 3 of this invention The perspective view which showed the connecting terminal of Example 4 of this invention The perspective view which showed the connecting terminal of Example 5 of this invention The perspective view which showed the connecting terminal of Example 6 of this invention The perspective view which showed the connecting terminal of Example 7 of this invention The perspective view which showed the connecting terminal of Example 8 of this invention The perspective view which showed the connecting terminal of Example 9 of this invention The perspective view which showed the connecting terminal of Example 10 of this invention The perspective view which showed the connecting terminal of Example 11 of this invention The perspective view which showed the connecting terminal of Example 12 of this invention

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Positive electrode plate 1a Side edge part of positive electrode plate 2 Negative electrode plate 2a Side edge part of negative electrode plate 3 Separator 4 Electrode plate group 5 Upper collector 5a Injection port 6 Lower collector 7 Connection terminal 7a Connecting part 7b Tongue piece 7c Projection piece 8 Bottomed case 8a Groove portion 8b Support portion 8c Gutter portion 9 Insulating ring 10 Sealing body 10a Cover plate 10b Rubber valve body 10c Cap 10d Gasket

Claims (5)

A bottomed case that also serves as one external terminal containing an electrode plate group and an electrolyte solution, each of which is formed by laminating a strip-like positive electrode plate and a negative electrode plate via a separator or winding them in a spiral shape, and this bottomed case A sealing body that also serves as the other external terminal that seals the opening at the upper end of the sealing member by caulking and electrically connects the sealing body and an upper current collector welded to one electrode plate of the electrode plate group A battery having a connection terminal,
A battery in which a part of an outer peripheral portion of the connection terminal and a part of a sealing body are electrically connected by caulking.   2. The battery according to claim 1, wherein a plurality of tongue pieces are provided in a connecting portion that constitutes an outer peripheral portion of the connection terminal, and a plurality of tongue pieces that are bent in a downward direction are provided in a radial direction.   The flange part which protrudes outward is provided in the opening part of the upper end part of the said bottomed case, The sealing body installed in this collar part is crimped and sealed by the bending part of the peripheral part of the collar part. battery.   The battery according to claim 2 or 3, wherein 2 to 6 tongue pieces are provided. The battery according to claim 2 or 3, wherein a protruding piece along the outer peripheral portion of the connection terminal is provided at the tip of the tongue piece.

Images