JP4079563B2 - Storage battery and manufacturing method thereof - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention provides a battery case having an opening that also serves as a terminal of one electrode, a sealing body that also serves as a terminal of the other electrode that seals the opening, and at least one end of positive and negative electrodes accommodated in the battery case In particular, the present invention relates to a storage battery including an electrode body having a current collector connected to a portion thereof, and a manufacturing method thereof, and more particularly, to a connection structure between a current collector connected to at least one of positive and negative electrodes and a sealing body and a welding method thereof It is about improvement.
[0002]
[Prior art]
In general, alkaline storage batteries such as nickel-hydride storage batteries and nickel-cadmium storage batteries interpose a separator between a positive electrode and a negative electrode, wind them in a spiral shape, and then attach a current collector to the end of the positive electrode or the negative electrode. Connect to form an electrode body. Next, the electrode body is housed in a metal battery case and a lead portion extending from the current collector is welded to the sealing body, and then the sealing body is attached to the opening of the battery case with an insulating gasket interposed therebetween and sealed. It is manufactured by.
[0003]
When such alkaline storage batteries are used for applications such as electric tools and electric vehicles that charge and discharge at a high rate, electrical resistance at the lead portion connecting between the current collector and the sealing body, particularly among battery configurations. Greatly affects battery characteristics. That is, when the electrical resistance at the lead portion is large, discharging with a large current causes a problem that a large voltage drop due to the electrical resistance at the lead portion occurs and the battery voltage decreases. Therefore, in Japanese Patent No. 2762599, it is proposed to configure the lead part by using a plurality of current collecting parts, or to reduce the electrical resistance at the lead part by increasing the thickness of the current collecting part. Became.
[0004]
[Problems to be solved by the invention]
By the way, when a plurality of current collecting parts constituting the lead part are used, the number of parts is increased and the lead part is not flexible, so that it is difficult to weld the seal part and the seal part is attached to the battery case. When sealing by caulking to the opening, it becomes difficult to bend the lead portion, resulting in poor productivity. In addition, if the thickness of the current collecting parts constituting the lead portion is increased, the current that is ineffective for the welding current for resistance welding is increased, the weldability with the sealing body is deteriorated, and the sealing body is opened to the battery case. When caulking to the part and sealing, it becomes difficult to bend the lead part, resulting in a problem of poor productivity.
[0005]
On the other hand, when welding the lead part to the sealing body, after the sealing body is adjacent to the lead part rising vertically from the current collector and the welding electrode is pressed against the side surface of the lead part, the lead part is resistance-welded to the sealing body The lead portion is bent to attach the sealing body to the opening portion of the battery case, and the end portion of the opening portion is crimped to be sealed. In general, the use of a thick lead lead portion has a lower specific resistance and a lower battery internal resistance.
[0006]
However, as described above, after welding the lead portion to the sealing body, in order to attach the sealing body to the opening of the battery case, a long lead portion is used, and the lead portion is bent at the time of sealing. Thus, it is necessary to attach the sealing body to the opening of the battery case. Therefore, the length of the lead portion needs to be at least the radius of the electrode body, and in order to bend the lead portion, a thin and long lead portion must be used. A problem arises that the specific resistance increases and the internal resistance of the battery increases.
[0007]
Accordingly, the present invention has been made to solve the above-described problems, and adopts a connection structure that can reliably weld the sealing body and the current collector even if the current collecting lead portion is omitted, thereby achieving high efficiency. A first object is to obtain a storage battery having excellent discharge performance. It is a second object of the present invention to provide a welding method that employs such a connection structure to reliably weld the sealing body and the current collector.
[0008]
[Means for Solving the Problems]
To achieve the above first object, the storage battery of the present invention Rutotomoni includes three projections on the lower surface of the sealing body, the center of the lower surface of the three projections the sealing member and its center of gravity It is formed on the position where the apexes of an equilateral triangle, these three projections and one collector and the body is fixed connected or provided with three projections on the upper surface of the current collector Rutotomoni, these 3 Each of the projections is formed at a vertex of an equilateral triangle having the center of the upper surface of the current collector as its center of gravity, and the three projections and the sealing body are fixedly connected.
Thus, Rutotomoni includes three projections on the lower surface of the sealing body, these three projections are formed on the position where the apexes of an equilateral triangle that the center of the lower surface of the sealing member and its center of gravity dolphin or Rutotomoni includes three projections on the upper surface of the current collector, these three projections are formed on the position where the apexes of an equilateral triangle that the center of the upper surface of the current collector and the center of gravity Even if the current collecting lead portion is omitted, the sealing body and the current collector can be reliably welded, and the electric resistance of the current collecting lead portion can be made zero. As a result, it is possible to improve the output characteristics of the battery and prevent a decrease in battery voltage during high rate discharge.
[0009]
In this case, if these protrusions are not uniformly in contact with the upper surface of the current collector or the lower surface of the sealing body, a phenomenon (explosion) in which the molten metal is scattered during welding occurs, so-called “welding” Dust "occurs and this is one of the causes of battery short circuit. For this reason, the protrusion is formed at the position of the apex of the equilateral triangle with the center of the lower surface of the sealing body as its center of gravity, or at the position of the apex of the equilateral triangle with the center of the upper surface of the current collector as its center of gravity. It needs to be formed.
[0010]
Moreover, in order to achieve the said 2nd objective, the manufacturing method of the storage battery of this invention becomes a vertex of the equilateral triangle which makes the center of the lower surface of the said sealing body the three protrusion parts on the lower surface of the sealing body, and the gravity center. or formed at a position, or a protruding part forming step of forming three projections on the upper surface of the current collector to the vertex a position of an equilateral triangle centered its center of gravity to the upper surface of the current collector, the battery case An electrolyte injection process for injecting an electrolyte solution into the battery case, an arrangement process for arranging a sealing body in the opening of the battery case, and a projection and an upper surface of the current collector by passing a current between the battery case and the sealing body. A welding step of welding the contact portion of the sealing body or welding the contact portion between the lower surface of the sealing body and the protrusion, and a sealing step of sealing the sealing body to the opening of the battery case.
[0011]
In this way, when the electrolyte is injected into the battery case in the electrolyte injection process, when a voltage is applied between the battery case and the sealing body in the welding process, the sealing body → the protrusion → the current collector → the positive / negative electrode → Since current flows through the battery case path or vice versa (welding process), the contact part between the protrusion and the upper surface of the current collector or the contact part between the lower surface of the sealing body and the protrusion is welded. Will be able to.
[0012]
Alternatively, three protrusions are formed on the bottom surface of the sealing body at a position that becomes the apex of an equilateral triangle with the center of the bottom surface of the sealing body as its center of gravity , or three protrusions on the top surface of the current collector A protrusion forming step for forming the apex of an equilateral triangle having the center of the upper surface of the current collector as its center of gravity; an electrolyte injecting step for injecting an electrolyte into the battery case; and a current collector and a sealing body An electric current is applied between the battery case and the sealing body, an arranging step of arranging the sealing body in the opening of the battery case so that the sealing body is in contact, a sealing step of sealing the sealing body in the opening of the battery case, and Or a welding step of welding the contact portion between the protrusion and the upper surface of the current collector or welding the contact portion between the lower surface of the sealing body and the protrusion. Contact portion between the upper surface of the current collector or the contact portion between the lower surface of the sealing body and the protrusion It is possible to weld.
[0013]
In this case, if the contact portion between the protrusion and the upper surface of the current collector or the contact portion between the lower surface of the sealing body and the protrusion is not in close contact, a phenomenon (explosion) in which the molten metal scatters occurs. “Welding dust” occurs, which is one of the causes of battery short circuit. For this reason, in the welding process, it is necessary to pressurize the sealing body toward the current collector and to allow a current to flow between the battery case and the sealing body. As a result, the contact portion between the protrusion and the upper surface of the current collector or the contact portion between the lower surface of the sealing body and the protrusion is brought into close contact, and no explosion occurs.
[0014]
Then, it is necessary to uniformly pressurize the contact portion between the protrusion and the upper surface of the current collector or the contact portion between the lower surface of the sealing body and the protrusion. For example, when four protrusions are provided, the current collector When distortion occurs in the surface of the sealing member or distortion occurs on the lower surface of the sealing body, the four projections cannot be uniformly pressed, and rattling occurs.
For this reason, the protrusion is formed at the position of the apex of the equilateral triangle with the center of the lower surface of the sealing body as its center of gravity, or at the position of the apex of the equilateral triangle with the center of the upper surface of the current collector as its center of gravity. There is a need to. In this way, when the three projections are provided, even if the current collector is distorted or the bottom surface of the sealing body is distorted, the three projections can be uniformly pressurized. Become.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Below, an embodiment at the time of applying the present invention to a nickel-hydrogen storage battery is described based on figures. FIG. 1 is a view showing a sealing body of the present invention, FIG. 1 (a) is a bottom view thereof, FIG. 1 (b) is a side view thereof, and a broken cross-sectional view thereof. . FIG. 2 is a cross-sectional view showing a state in which the sealing body of FIG. 1 is welded to the electrode body. 3 is a cross-sectional view showing a nickel-hydrogen storage battery formed by welding the sealing body of FIG. 1 to an electrode body. FIG. 4 is a view showing an electrode body welded with the current collector of the present invention, FIG. 4 (a) shows a top view thereof, FIG. 4 (b) shows a side view thereof and a fractured surface with a part thereof broken. FIG. FIG. 5 is a cross-sectional view showing a nickel-hydrogen storage battery formed by welding a sealing body to the current collector of FIG. FIG. 6 shows a storage battery of a comparative example, and is a cross-sectional view showing a state where a lead portion is welded to a sealing body.
[0016]
1. Example 1
The nickel-hydrogen storage battery of Example 1 includes a nickel positive electrode plate 11 and a hydrogen storage alloy negative electrode plate 12. The nickel positive electrode plate 11 is formed by forming a nickel sintered porous body on the surface of an electrode plate core made of punching metal, and then filling the nickel sintered porous body with an active material mainly composed of nickel hydroxide by a chemical impregnation method. Are made. On the other hand, the hydrogen storage alloy negative electrode plate 12 is prepared by filling the surface of an electrode plate core made of punching metal with a paste-like negative electrode active material made of hydrogen storage alloy, drying, and rolling to a predetermined thickness. Has been.
[0017]
A separator 13 was interposed between the nickel positive electrode plate 11 and the hydrogen storage alloy negative electrode plate 12, and a spiral electrode group was prepared by winding the separator 13 in a spiral shape. An end portion 11a of a punching metal that is an electrode plate core body of the nickel positive electrode plate 11 is exposed at the upper end surface of the spiral electrode group, and an electrode plate core body of the hydrogen storage alloy negative electrode plate 12 is exposed at the lower end surface. An end portion 12a of a punching metal is exposed. The positive electrode core body exposed on the upper end surface of the spiral electrode group is welded with a disk-shaped positive electrode current collector 14 having a large number of openings (not shown) and a liquid injection opening, and the negative electrode core exposed on the lower end surface. A disc-shaped negative electrode current collector 15 having a large number of openings (not shown) in the body was welded to produce a spiral electrode body 10.
[0018]
When assembling the nickel-hydrogen storage battery, the electrode body 10 welded with the positive electrode current collector 14 is accommodated in a bottomed cylindrical battery case 16 in which nickel is plated on iron (the outer surface of the bottom surface becomes a negative electrode external terminal) 16. To do.
Next, a lid body 31 formed by forming a circular downward projecting portion 32 on the bottom surface and a sealing body 30 comprising a positive electrode cap (positive electrode external terminal) 35 are prepared. The sealing body 30 includes a valve body including a spring 36 and a valve plate 37 interposed between the lid body 31 and the positive electrode cap 35, and a gas vent hole 34 is formed at the center of the lid body 31.
[0019]
Three projections 33, 33, 33 are formed in advance on the lower surface of the downward projecting portion 32 of the lid 31. These three protrusions 33, 33, 33 are formed at the positions of the vertices of an equilateral triangle having the center of the gas vent hole 34 of the lid 31 as the center of gravity. As a result, even if the current collector 14 is distorted or the lower surface of the downward projecting portion 32 of the sealing body 30 is distorted, the three protruding portions 33, 33, 33 are uniformly pressed. .
[0020]
Next, a vibration isolating ring 18 was inserted into the upper inner peripheral side of the battery case 16, and a groove was formed on the outer peripheral side of the battery case 16 to form a recess 16 a at the upper end of the vibration isolating ring 18. Thereafter, an electrolytic solution made of a 30% by mass potassium hydroxide (KOH) aqueous solution was injected into the battery case 16. Next, three protrusions 33, 33, 33 formed on the lower surface of the downward projecting portion 32 of the sealing body 30 are in contact with the upper surface of the positive electrode current collector 14 at the upper portion of the opening of the battery case 16. Arranged.
[0021]
After the sealing body 30 is disposed as described above, one welding electrode W1 is disposed on the upper surface of the positive electrode cap (positive electrode external terminal) 35, and the other welding electrode is disposed on the lower surface of the bottom surface (negative electrode external terminal) of the battery case 16. W2 was placed. Thereafter, while applying a pressure of 2 × 10 ⁶ N / m ² between the pair of welding electrodes W1 and W2, a voltage of 24V is applied between the welding electrodes W1 and W2 in the discharge direction of the battery, and 3KA Was applied for about 15 msec. By this energization process, current concentrates on the contact portions between the three protrusions 33, 33, 33 formed on the lower surface of the downward projecting portion 32 of the sealing body 30 and the upper surface of the positive electrode current collector 14, and these The protrusions 33, 33, 33 and the contact portion between the upper surface of the positive electrode current collector 14 were welded to form a welded portion. At the same time, the contact portion between the lower surface of the negative electrode current collector 15 and the upper surface of the bottom surface (negative electrode external terminal) of the battery case 16 was welded to form a welded portion.
[0022]
Next, the insulating gasket 19 is fitted to the periphery of the sealing body 30 and a pressure is applied to the sealing body 30 using a press machine so that the sealing body 30 is placed in the battery case until the lower end of the insulating gasket 19 is positioned at the recess 16a. 16 was pushed into. Thereafter, the opening edge of the battery case 16 was crimped inward to seal the battery, and a cylindrical nickel-hydrogen storage battery having a nominal capacity of 6.5 Ah as shown in FIG. 3 was produced. The nickel-hydrogen storage battery of Example 1 produced in this way was designated as battery A.
[0023]
2. Example 2
The nickel-hydrogen storage battery of Example 2 includes the same nickel positive electrode plate 11 and hydrogen storage alloy negative electrode plate 12 as in Example 1 described above. When assembling the nickel-hydrogen storage battery of Example 2, first, the separator 13 is interposed between the nickel positive electrode plate 11 and the hydrogen storage alloy negative electrode plate 12, and the spiral electrode group is formed in a spiral shape. Produced. As in Example 1 described above, the end portion 11a of the punching metal which is the electrode plate core of the nickel positive electrode plate 11 is exposed at the upper end surface of the spiral body, and the hydrogen storage alloy negative electrode is formed at the lower end surface. The end of the punching metal that is the electrode plate core of the plate 12 is exposed.
[0024]
Next, as shown in FIG. 4, a disc-shaped positive electrode current collector 20 having a large number of openings 21, 21, 21..., A liquid injection opening 22, and three projections 23, 23, 23 is provided. prepare. The three protrusions 23, 23, 23 are formed in advance. These three protrusions 23, 23, 23 are formed at the positions of the apexes of an equilateral triangle with the center of the liquid injection opening 22 of the disc-like positive electrode current collector 20 as the center of gravity. As a result, even if the current collector 20 is distorted or the lower surface of the downward projecting portion of the sealing body 17 is distorted, the three protrusions 23, 23, 23 are uniformly pressed. Next, the positive electrode current collector 20 is welded to the positive electrode core body exposed at the upper end surface of the spiral electrode group, and the disk-shaped electrode having a large number of openings (not shown) in the negative electrode core body exposed at the lower end surface. The negative electrode current collector 15 was welded to produce a spiral electrode body 10.
[0025]
Thereafter, the electrode body 10 is housed in a bottomed cylindrical battery case 16 in which nickel is plated on iron (the outer surface of the bottom surface is a negative electrode external terminal) 16. Next, a vibration isolating ring 18 was inserted into the upper inner peripheral side of the battery case 16, and a groove was formed on the outer peripheral side of the battery case 16 to form a recess 16 a at the upper end of the vibration isolating ring 18. Thereafter, an electrolytic solution made of a 30 wt% potassium hydroxide (KOH) aqueous solution was injected into the battery case 16. Next, a sealing body 17 was disposed on the upper part of the opening of the battery case 16. The sealing body 17 includes a lid body 17a formed with a circular downward projecting portion on the bottom surface, a positive electrode cap (positive electrode external terminal) 17b, and a spring 17c interposed between the lid body 17a and the positive electrode cap 17b. And a valve plate 17d. A gas vent hole is formed in the center of the lid 17a.
[0026]
After the sealing body 17 is arranged above the opening of the battery case 16 as described above, one welding electrode W1 is arranged on the upper surface of the positive electrode cap (positive electrode external terminal) 17a, and the bottom surface of the battery case 16 (external electrode outside the negative electrode). The other welding electrode W2 was disposed on the lower surface of the terminal. Thereafter, while applying a pressure of 2 × 10 ⁶ N / m ² between the pair of welding electrodes W1 and W2, a voltage of 24V is applied between the welding electrodes W1 and W2 in the discharge direction of the battery, and 3KA Was applied for about 15 msec. By this energization process, the current concentrates on the contact portion between the three protrusions 23, 23, 23 formed on the bottom surface of the sealing body 17 and the upper surface of the positive electrode current collector 20, and these three protrusions The contact part of 23,23,23 and the bottom face of the sealing body 17 was welded, and the welding part was formed. At the same time, the contact portion between the lower surface of the negative electrode current collector 15 and the upper surface of the bottom surface (negative electrode external terminal) of the battery case 16 was welded to form a welded portion.
[0027]
Next, an insulating gasket 19 is fitted on the periphery of the sealing body 17, and a pressure is applied to the sealing body 17 using a press machine, and the sealing body 17 is placed in the battery case until the lower end of the insulating gasket 19 is positioned at the recess 16a. 16 was pushed into. Thereafter, the opening edge of the battery case 16 was crimped inward to seal the battery, and a cylindrical nickel-hydrogen storage battery having a nominal capacity of 6.5 Ah as shown in FIG. 5 was produced. The nickel-hydrogen storage battery of Example 2 produced in this manner was designated as battery B.
[0028]
3. Comparative Example As shown in FIG. 6, the positive electrode core exposed on the upper end surface of the spiral electrode group produced in the same manner as in Example 1 described above has a large number of openings, and the lead portion 14b extends from a part thereof. A disc-shaped positive electrode current collector 14a was welded. On the other hand, a disk-shaped negative electrode current collector 15 having a large number of openings was welded to the negative electrode core exposed at the lower end surface of the spiral body to produce a spiral electrode body 10a. The electrode body 10a is accommodated in the battery case 16, and the negative electrode current collector 15 is spot welded to the inner bottom surface of the battery case 20 (in FIG. 6, a welding electrode is inserted at the center of the wound electrode body 10a). However, FIG. 6 is a diagram schematically showing that there is actually a space for inserting a welding electrode). Thereafter, the vibration isolating ring 18 was inserted into the upper inner peripheral side of the battery case 16, and grooving was performed on the outer peripheral side of the battery case 16 to form a recess 16 a at the upper end portion of the vibration isolating ring 18.
[0029]
Next, the lead portion 14b extended from the positive electrode current collector 14a was bent vertically, and then resistance-welded to the bottom surface of the sealing body 17 at the end portion of the lead portion 14b. Next, after injecting an electrolytic solution made of a 30 wt% potassium hydroxide (KOH) aqueous solution into the battery case 16, the lead part 14b is bent, and the sealing body 17 having the insulating gasket 19 fitted on the periphery thereof is formed into the battery. Arranged in the opening of the case 16. Subsequently, the opening edge of the battery case 16 was crimped inward to seal the battery, and a cylindrical nickel-hydrogen storage battery having a nominal capacity of 6.5 Ah was produced. The nickel-hydrogen storage battery of the comparative example produced in this way was designated as battery X.
[0030]
4). Battery Characteristic Test (1) Activation Using the batteries A and B of the examples prepared as described above and the battery X of the comparative example, a current value of 650 mA (0.1 C) at room temperature (ambient temperature 25 ° C.). After charging for 8 hours, the battery is paused for 1 hour, and then discharged at a current value of 1300 mA (0.2 C) until the battery voltage reaches 0.8 V. This charge / discharge cycle is repeated 10 times. The battery was activated.
[0031]
(2) IV characteristic test Next, using the batteries A and B of Examples 1 and 2 activated as described above and the battery X of Comparative Example, 1300 mA (2C) at room temperature (ambient temperature 25 ° C.) The battery was discharged at a current value of 1300 mA (0.2 C) for 3 hours at a current value of 1300 mA (0.2 C). After resting for 1 hour, the battery was discharged at a current value of 25 A for 30 seconds, and the battery voltage 10 seconds after the start of discharge was measured.
Then, after charging the power for the discharged capacity, similarly, the battery was discharged at a current value of 50A, 70A, and 100A for 30 seconds, and the battery voltage 10 seconds after the start of discharge was measured. When the IV voltage (IV characteristic) is obtained with the battery voltage 10 seconds after the start of discharge thus obtained as the vertical axis and the current values as the horizontal axis, the results shown in FIG. 7 are obtained. It became.
[0032]
As can be seen from FIG. 7, the slope of the IV line of the batteries A and B of Examples 1 and 2 is small while the slope of the IV line of the battery X of the comparative example is large. From this, it can be seen that the operating voltages of the batteries A and B of Examples 1 and 2 are both high and the battery internal resistance is low. This is because the batteries A and B of Examples 1 and 2 have a protrusion 33 on the lower surface of the sealing body 30, and the contact portion between the protrusion 33 and the upper surface of the positive electrode current collector 14 is directly welded, or the positive electrode Since the upper surface of the current collector 20 has a protrusion 23 and the contact portion between the protrusion 23 and the lower surface of the sealing body 17 is directly welded, the internal resistance at these contact portions is reduced and high output characteristics are obtained. Is considered to have been obtained.
[0033]
In the above-described embodiments (Examples 1 and 2), a voltage is applied between the positive electrode cap 35 (17b) and the bottom surface of the battery case 16 to perform an energization process, so that the protrusion 33 of the sealing body 30 is applied. After welding the contact portion between the positive electrode current collector 14 and the upper surface of the positive electrode current collector 14 or the contact portion between the protrusion 23 of the positive electrode current collector 20 and the lower surface of the sealing body 17, the opening of the battery case 16 is sealed with the sealing body 30 (17). Although the example of sealing was demonstrated, after sealing the opening part of the battery case 16 with the sealing body 30 (17), a voltage is applied between the positive electrode cap 35 (17b) and the bottom face of the battery case 16, and an energization process is performed. The contact portion between the projection 33 of the sealing body 30 and the upper surface of the positive electrode current collector 14 or the contact portion between the projection 23 of the positive electrode current collector 20 and the lower surface of the sealing body 17 may be welded. Results were obtained.
[0034]
In the above-described embodiments (Examples 1 and 2), a voltage of 24 V is applied in the discharge direction of the battery between the positive electrode cap (positive electrode external terminal) and the bottom surface of the battery case (negative electrode external terminal). However, there was no correlation in the direction of the current applied to the battery, and similar results were obtained regardless of whether the battery was discharged or charged. . In addition, regarding the applied current value, the same effect was obtained at 300 A or more regardless of the size of the battery. Note that a direct current or an alternating current power source can be used as a power source of a welding current that flows between the battery case and the sealing body in the welding process.
[0035]
However, when an extremely excessive current is applied, even if it is applied for a short time, each projection 33 or 23 melts, and the current value to be melted depends on the material and shape of the sealing body or current collector. Since the upper limit value changes, the current value needs to be a value at which the protrusions 33 or 23 are not blown at 300 A or more. Furthermore, if the application time is 0.25 msec or more, the same effect can be obtained. However, if it is applied over a time as long as 1 second, each projection 33 or 23 is blown out, which is not preferable.
[0036]
Moreover, in embodiment (Example 1, 2) mentioned above, an electric current is sent between a positive electrode external terminal (positive electrode cap) and a negative electrode external terminal (bottom surface of a battery case), and a sealing body and an electrical power collector are made. Although an example was described in which welding of the negative electrode current collector and the inner bottom surface of the battery case was performed at the same time, the positive electrode external terminal (positive electrode) was spot welded to the negative electrode current collector and the inner bottom surface of the battery case. The sealing body and the current collector may be welded by passing an electric current between the cap) and the negative electrode external terminal (the bottom surface of the battery case).
In this case, it is necessary to provide a space for inserting a welding electrode at the center of the spiral electrode body, and this space may be formed by a core space when the spiral electrode group is formed.
[0037]
Further, in the above-described embodiment, the example in which the sealing body is the positive electrode terminal and the battery case is the negative electrode terminal has been described. However, the sealing body may be the negative electrode terminal and the battery case may be the positive electrode terminal. In this case, the positive electrode current collector is welded to the inner bottom surface of the battery case, and the bottom surface of the sealing body is welded to the negative electrode current collector.
Furthermore, in the above-described embodiment, an example in which the present invention is applied to a nickel-hydrogen storage battery has been described. However, the present invention is not limited to a nickel-hydrogen storage battery, but may be applied to other storage batteries such as a nickel-cadmium storage battery. Obviously we can do it.
[Brief description of the drawings]
FIG. 1 is a view showing a sealing body of the present invention, FIG. 1 (a) is a bottom view thereof, FIG. 1 (b) is a side view thereof, and a cross-sectional view of a part thereof.
2 is a cross-sectional view showing a state in which the sealing body of FIG. 1 is welded to an electrode body.
3 is a cross-sectional view showing a nickel-hydrogen storage battery formed by welding the sealing body of FIG. 1 to an electrode body.
4 is a view showing an electrode body welded with a current collector of the present invention, FIG. 4 (a) is a top view thereof, FIG. 4 (b) is a side view thereof, and a cross-sectional view in which a part thereof is broken. It is.
5 is a cross-sectional view showing a nickel-hydrogen storage battery formed by welding a sealing body to the current collector of FIG. 4. FIG.
FIG. 6 is a cross-sectional view showing a storage battery of a conventional example (comparative example), in which a lead portion is welded to a sealing body.
FIG. 7 is a graph showing voltage (V) -current (I) characteristics of each battery.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 ... Electrode body, 11 ... Positive electrode plate, 12 ... Negative electrode plate, 13 ... Separator, 14 ... Positive electrode collector (Example 1), 15 ... Negative electrode collector, 16 ... Battery case (negative electrode external terminal), 16a ... Groove, 17 ... Sealing body (Example 2), 17a ... Lid, 17b ... Positive electrode cap (positive electrode external terminal), 18 ... Anti-vibration ring, 19 ... Insulating gasket, 20 ... Positive electrode current collector (Example 2), 23 ... Projection, 30 ... Sealing body (Example 1), 31 ... Lid, 33 ... Projection, 35 ... Positive electrode cap (positive electrode external terminal), W1, W2 ... Welding electrode

Claims (9)

A battery case having an opening that also serves as a terminal for one electrode, a sealing body that also serves as a terminal for the other electrode that seals the opening, and at least one end of positive and negative electrodes accommodated in the battery case. A storage battery comprising an electrode body to which an electric body is connected,
Rutotomoni provided with three projections on the lower surface of the sealing body, these three projections is formed in a position where the apexes of an equilateral triangle that the center of the lower surface of the sealing member and its center of gravity, these 3 A storage battery, wherein a plurality of protrusions and the current collector are fixedly connected. A battery case having an opening that also serves as a terminal for one electrode, a sealing body that also serves as a terminal for the other electrode that seals the opening, and at least one end of positive and negative electrodes accommodated in the battery case. A storage battery comprising an electrode body to which an electric body is connected,
Rutotomoni provided with three projections on the upper surface of the current collector, these three pieces of protrusions be formed at a position where the apexes of an equilateral triangle that the center of the upper surface of the current collector and the center of gravity, A storage battery characterized in that these three protrusions and the sealing body are fixedly connected. In a battery case having an opening that also serves as a terminal of one electrode, an electrode body in which a current collector is connected to at least one of the positive and negative electrodes is accommodated, and then the opening serves as a terminal of the other electrode A method of manufacturing a storage battery formed by sealing with a sealing body,
A protrusion forming step of forming three protrusions on the lower surface of the sealing body at a position that is the apex of an equilateral triangle having the center of the lower surface of the sealing body as its center of gravity ;
An electrolyte injection step of injecting an electrolyte into the battery case;
An arrangement step of arranging the sealing body in the opening of the battery case;
A welding step in which a current is passed between the battery case and the sealing body to weld a contact portion between the protrusion and the upper surface of the current collector;
A method for producing a storage battery, comprising: a sealing step of sealing the sealing body in an opening of the battery case. In a battery case having an opening that also serves as a terminal of one electrode, an electrode body in which a current collector is connected to at least one of the positive and negative electrodes is accommodated, and then the opening serves as a terminal of the other electrode A method of manufacturing a storage battery formed by sealing with a sealing body,
A protrusion forming step of forming three protrusions on the upper surface of the current collector at a position that is the apex of an equilateral triangle having the center of the upper surface of the current collector as its center of gravity ;
An electrolyte injection step of injecting an electrolyte into the battery case;
An arrangement step of arranging the sealing body in the opening of the battery case so that the current collector and the sealing body are in contact with each other;
A welding step in which a current is passed between the battery case and the sealing body to weld a contact portion between the lower surface of the sealing body and the protrusion;
A method for producing a storage battery, comprising: a sealing step of sealing the sealing body in an opening of the battery case. The said sealing body is pressurized toward the said electrical power collector in the said welding process, An electric current was sent between the said battery case and the said sealing body, The Claim 3 or Claim 4 characterized by the above-mentioned. Storage battery manufacturing method. In a battery case having an opening that also serves as a terminal of one electrode, an electrode body in which a current collector is connected to at least one of the positive and negative electrodes is accommodated, and then the opening serves as a terminal of the other electrode A method of manufacturing a storage battery formed by sealing with a sealing body,
A protrusion forming step of forming three protrusions on the lower surface of the sealing body at a position that is the apex of an equilateral triangle having the center of the lower surface of the sealing body as its center of gravity ;
An electrolyte injection step of injecting an electrolyte into the battery case;
An arrangement step of arranging the sealing body in the opening of the battery case so that the current collector and the sealing body are in contact with each other;
A sealing step of sealing the sealing body in the opening of the battery case;
A method for manufacturing a storage battery, comprising: a welding step in which a current is passed between the battery case and the sealing body to weld a contact portion between the protrusion and the upper surface of the current collector. According to claim 6, characterized in that the sealing member so as to closely contact with the current collector with the lower surface of the projecting portion of the sealing member is pressurized toward the current collector in the closed step Storage battery manufacturing method. In a battery case having an opening that also serves as a terminal of one electrode, an electrode body in which a current collector is connected to at least one of the positive and negative electrodes is accommodated, and then the opening serves as a terminal of the other electrode A method of manufacturing a storage battery formed by sealing with a sealing body,
A protrusion forming step of forming three protrusions on the upper surface of the current collector at a position that is the apex of an equilateral triangle having the center of the upper surface of the current collector as its center of gravity ;
An electrolyte injection step of injecting an electrolyte into the battery case;
An arrangement step of arranging the sealing body in the opening of the battery case so that the current collector and the sealing body are in contact with each other;
A sealing step of sealing the sealing body in the opening of the battery case;
A method for manufacturing a storage battery, comprising: a welding step in which a current is passed between the battery case and the sealing body to weld a contact portion between a lower surface of the sealing body and the protrusion. The storage battery according to claim 8 , wherein the sealing body is pressurized toward the current collector in the sealing step so that the lower surface of the sealing body and the protrusion are in close contact with each other. Method.

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