JP2001160388A - Battery and manufacturing method therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a battery of improved high-rate discharge performance by adopting a connection structure in which a sealed body and an electric collector are made surely weldable, even if the collecting lead portion is omitted. SOLUTION: This battery comprised of a projection 33 at the lower surface of a sealed body 30, and the projection 33 and a collector 14 are fixedly connected. Thus, by having the projection 33 at the lower surface of the sealing 30, the sealed body 30 and the collector 13 can be surely made weldable, even if a collecting lead portion has been omitted, and the electrical resistance of the collecting lead can be set to zero. Thereby, the output characteristics of the battery are improved, and the decrease in the battery voltage during a high rate discharging can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a battery case having an opening serving also as a terminal of one pole, a sealing body sealing the opening and serving as a terminal of the other pole, and a positive electrode housed in the battery case. The present invention relates to a storage battery including an electrode body having a current collector connected to at least one end of a negative electrode and a method for manufacturing the same, and in particular, relates to a method of manufacturing a battery comprising: a current collector connected to at least one of a positive electrode and a negative electrode; The present invention relates to an improvement in a connection structure and a welding method thereof.

[0002]

2. Description of the Related Art Generally, an alkaline storage battery such as a nickel-hydride battery or a nickel-cadmium storage battery has a separator interposed between a positive electrode and a negative electrode, and spirally winds them. To form an electrode body. Then, the electrode body is housed in a metal battery case, and a lead extending from the current collector is welded to a sealing body, and the sealing body is attached to an opening of the battery case with an insulating gasket interposed therebetween to be sealed. It is manufactured by

[0003] When such an alkaline storage battery is used for charging and discharging at a high rate, such as an electric tool or an electric vehicle, a lead portion connecting between a current collector and a sealing body is particularly used in a battery configuration. Has a significant effect on battery characteristics. That is, when the electric resistance at the lead portion is large, when a discharge is performed with a large current, a large voltage drop due to the electric resistance at the lead portion occurs, causing a problem that the battery voltage decreases. In view of this, Japanese Patent No. 2762599 proposes that a lead portion is formed by using a plurality of current collecting components, or that the thickness of the current collecting component is increased to reduce the electrical resistance at the lead portion. Became.

[0004]

In the case where a plurality of current collecting parts are included in the lead part, the number of parts is increased and the lead part is not flexible, so that it is difficult to weld the lead part. In addition, when the sealing body is sealed by caulking the opening of the battery case, it is difficult to bend the lead portion, resulting in a problem that productivity is deteriorated. In addition, if the thickness of the current collecting component constituting the lead portion is increased,
Ineffective welding current for resistance welding increases and the weldability with the sealing body deteriorates, and it is difficult to bend the lead part when sealing the sealing body with the opening of the battery case closed. As a result, there was a problem that productivity was poor.

On the other hand, when welding a lead portion to a sealing body,
The sealing body is placed adjacent to the lead that rises vertically from the current collector, the welding electrode is pressed against the side of the lead, and the lead is resistance-welded to the sealing body. It is attached to the opening, and the end of the opening is caulked to seal. Generally, when a lead portion having a large thickness and a short length is used, the specific resistance is reduced and the internal resistance of the battery is reduced.

However, as described above, after the lead is welded to the sealing body, in order to attach the sealing body to the opening of the battery case, a long lead is used.
At the time of sealing, it is necessary to attach the sealing body to the opening of the battery case by bending the lead. For this reason, the length of the lead must be at least as long as the radius of the electrode body, and in order to bend the lead, a thin and long lead must be used. There is a problem that the specific resistance increases and the internal resistance of the battery increases.

Therefore, the present invention has been made to solve the above-mentioned problem, and employs a connection structure that can reliably weld the sealing member and the current collector even if the current collecting lead portion is omitted. It is a first object to obtain a storage battery having excellent high-rate discharge performance. It is a second object of the present invention to provide a welding method that can reliably weld the sealing body and the current collector by employing such a connection structure.

[0008]

In order to achieve the first object, a storage battery of the present invention has at least one projection on the lower surface of a sealing body, and the projection and a current collector are provided. Are fixedly connected to each other, or at least one projection is provided on the upper surface of the current collector, and the projection and the sealing body are fixedly connected to each other. As described above, if at least one projection is provided on the lower surface of the sealing body, or at least one projection is provided on the upper surface of the current collector, the sealing body can be reliably provided even if the current collecting lead is omitted. And the current collector can be welded, and the electrical resistance of the current collecting lead can be reduced to zero. As a result, it is possible to improve the output characteristics of the battery and prevent the battery voltage from dropping during high-rate discharge.

[0009] In this case, if these projections do not uniformly contact the upper surface of the current collector or the lower surface of the sealing member, a phenomenon (bomb blast) occurs in which the molten metal is scattered during welding. So-called "welding dust" occurs, which is one of the causes of battery short circuit. For this reason, the protrusion is formed at the vertex position of the equilateral triangle whose center of gravity is the center of the lower surface of the sealing body, or at the vertex position of the equilateral triangle whose center of gravity is the center of the upper surface of the current collector. Must be formed.

In order to achieve the second object, a method of manufacturing a storage battery according to the present invention comprises forming at least one projection on the lower surface of the sealing body, or forming at least one projection on the upper surface of the current collector. Forming a protrusion, forming an electrolyte in the battery case, injecting an electrolyte into the battery case, arranging a sealing body in the opening of the battery case, and applying a current between the battery case and the sealing body. To weld the contact between the projection and the upper surface of the current collector or to weld the contact between the lower surface of the sealing body and the projection, and sealing to seal the sealing body to the opening of the battery case. Process.

As described above, when the electrolyte is injected into the battery case in the electrolyte injection step, when a voltage is applied between the battery case and the sealing body in the welding step, the sealing body → the protrusion →
Since current flows through the current collector → positive / negative electrode → battery case path or the reverse path (welding process), the contact between the protrusion and the upper surface of the current collector or the lower surface of the sealing body It becomes possible to weld the contact portion with the projection.

Alternatively, at least one projection is formed on the lower surface of the sealing body, or at least one projection is formed on the upper surface of the current collector, and an electrolyte is injected into the battery case. An electrolyte injecting step, an arranging step of arranging the sealing body in the opening of the battery case such that the current collector and the sealing body are in contact with each other, and a sealing step of sealing the sealing body to the opening of the battery case. A welding step of flowing a current between the battery case and the sealing body to weld a contact portion between the projection and the upper surface of the current collector or welding a contact portion between the lower surface of the sealing body and the projection. Even in this case, a contact portion between the projection and the upper surface of the current collector or a contact portion between the lower surface of the sealing body and the projection can be welded in the same manner as described above.

In this case, if the contact portion between the projection and the upper surface of the current collector or the contact portion between the lower surface of the sealing body and the projection is not in close contact, a phenomenon (bomb blast) in which the molten metal scatters occurs. As a result, so-called "welding dust" occurs, which is one of the causes of battery short circuit. For this reason, in the welding step, it is necessary to press 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 projection and the upper surface of the current collector or the contact portion between the lower surface of the sealing body and the projection is in close contact with each other, thereby preventing explosion.

It is necessary to uniformly press the contact portion between the projection and the upper surface of the current collector or the contact portion between the lower surface of the sealing body and the projection. For example, when four projections are provided,
When the current collector is distorted or the lower surface of the sealing member is distorted, the four protrusions cannot be pressed uniformly, resulting in rattling. For this reason, the protrusion is formed at the vertex position of the equilateral triangle whose center of gravity is the center of the lower surface of the sealing body, or at the vertex position of the equilateral triangle whose center of gravity is the center of the upper surface of the current collector. There is a need to. When the three projections are provided in this manner, even if the current collector is distorted or the lower surface of the sealing body is distorted, the three projections can be uniformly pressed. Become.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to a nickel-hydrogen storage battery will be described below with reference to the drawings. FIG. 1 is a view showing a sealing body of the present invention, FIG. 1 (a) is a bottom view thereof, and FIG. 1 (b) is a side view thereof and a view showing a partially cutaway cross-sectional view thereof. . Also,
FIG. 2 is a sectional view showing a state where the sealing body of FIG. 1 is welded to the electrode body. FIG. 3 is a 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 to which the current collector of the present invention is welded, FIG. 4 (a) shows a top view thereof, and FIG. 4 (b) shows a side view thereof and a fractured surface obtained by cutting a part thereof. FIG. FIG. 5 is a sectional view showing a nickel-hydrogen storage battery formed by welding a sealing body to the current collector of FIG. FIG. 6 is a cross-sectional view illustrating a storage battery of a comparative example, showing a state where a lead portion is welded to a sealing body.

1. Example 1 A nickel-hydrogen storage battery according to Example 1 has a nickel positive plate 1
1 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 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. It is manufactured. On the other hand, the hydrogen-absorbing alloy negative electrode plate 12 is prepared by filling a paste-like negative-electrode active material made of a hydrogen-absorbing alloy on the surface of an electrode plate core made of punching metal, drying it, and rolling it to a predetermined thickness. Have been.

A spiral electrode group was fabricated by spirally winding the nickel positive electrode plate 11 and the hydrogen storage alloy negative electrode plate 12 with a separator 13 interposed therebetween. At the upper end surface of the spiral electrode group, an end portion 11a of a punching metal which is an electrode core of the nickel positive electrode plate 11 is exposed, and at the lower end surface, an electrode plate core of the hydrogen storage alloy negative electrode plate 12 is provided. An end 12a of a certain punching metal is exposed. A disc-shaped positive electrode current collector 14 having a large number of openings (not shown) and a liquid injection opening in the positive electrode core exposed at the upper end surface of the spiral electrode group.
And a disk-shaped negative electrode current collector 15 having a large number of openings (not shown) was welded to the negative electrode core exposed at the lower end face, thereby producing a spiral electrode body 10.

When assembling the nickel-hydrogen storage battery, the electrode body 10 to which the positive electrode current collector 14 is welded is a bottomed cylindrical battery case in which nickel is plated with iron (the outer surface of the bottom surface is a negative electrode external terminal) 16 Housed inside. Next, a lid 31 having a circular lower protruding portion 32 formed on the bottom surface.
And a sealing body 30 composed of a positive electrode cap (positive electrode external terminal) 35 is prepared. The sealing body 30 has 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 in the center of the lid body 31.

On the lower surface of the lower projection 32 of the lid 31, three projections 33, 33, 33 are formed in advance. These three projections 33, 33, 33 are formed at the vertices of an equilateral triangle with the center of the gas vent hole 34 in the lid 31 as the center of gravity. Thereby, the current collector 14
May be distorted or the lower projection 32 of the sealing body 30
Of the three projections 33, 33, 3
3 is uniformly pressed.

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 concave portion 16 a at the upper end of the vibration isolating ring 18. Thereafter, an electrolyte composed of a 30% by mass aqueous solution of potassium hydroxide (KOH) was injected into the battery case 16. Then, above the opening of the battery case 16, the three protrusions 33, 33, 33 formed on the lower surface of the above-mentioned lower protruding portion 32 of the sealing body 30 come into contact with the upper surface of the positive electrode current collector 14. It was arranged as follows.

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 external terminal) 35, and the other welding electrode W1 is disposed on the lower surface of the bottom surface of the battery case 16 (negative external terminal). Was disposed.
Thereafter, 2 × 1 between the pair of welding electrodes W1 and W2.
0 ⁶ while applying a pressure of N / m ^2, these welding electrodes W
A voltage of 24 V is applied in the discharge direction of the battery between 1 and W2,
An energization process was performed in which a current of 3 KA was passed for about 15 msec. By this energization process, the lower protruding portion 3 of the sealing body 30
The current concentrates on a contact portion between the three protrusions 33, 33, 33 formed on the lower surface of the second and the upper surface of the positive electrode current collector 14, and these protrusions 33, 33, 33 and the positive electrode current collector 14 and the contact portion with the upper surface was 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.

Then, the insulating gasket 19 is fitted around the periphery of the sealing body 30, and a pressing force is applied to the sealing body 30 using a press machine until the lower end of the insulating gasket 19 reaches the position of the recess 16a. Was pushed into the battery case 16. Thereafter, the battery is sealed by caulking the opening edge of the battery case 16 inward, and has a nominal capacity of 6.0 as shown in FIG.
A 5 Ah cylindrical nickel-metal hydride battery was produced. The nickel-hydrogen storage battery of Example 1 thus manufactured was referred to as Battery A.

2. Example 2 A nickel-hydrogen storage battery of Example 2 includes a nickel positive electrode plate 11 and a hydrogen storage alloy negative electrode plate 1 similar to those of Example 1 described above.
2 is provided. When assembling the nickel-hydrogen storage battery of the second embodiment, first, the separator 1 is placed between the nickel positive electrode plate 11 and the hydrogen storage alloy negative electrode plate 12.
3 to form a spiral electrode group. The end portion 11a of the punched metal, which is the electrode plate core of the nickel positive electrode plate 11, is exposed on the upper end surface of the spiral body as in the first embodiment, and the hydrogen storage alloy negative electrode is formed on the lower end surface. The end of the punched metal which is the electrode plate core of the plate 12 is exposed.

Next, as shown in FIG.
A disc-shaped positive electrode current collector 20 having 1, 2, 21,..., A liquid injection opening 22 and three projections 23, 23, 23 is prepared. The three projections 23, 23, 23 are formed in advance. Note that these three projections 23, 2
Reference numerals 3 and 23 are formed at the vertices of an equilateral triangle having the center of the liquid injection opening 22 as the center of the disk-shaped positive electrode current collector 20. Thereby, even if the current collector 20 is distorted or the lower surface of the downwardly protruding portion of the sealing body 17 is distorted, the three projections 23, 23, 23 are uniformly pressed. Next, the positive electrode current collector 20 is welded to the positive electrode core exposed at the upper end surface of the spiral electrode group, and a disk-shaped negative electrode core exposed at the lower end surface has a number of openings (not shown). The spirally wound electrode body 10 was produced by welding the negative electrode current collector 15.

Thereafter, the electrode body 10 is housed in a bottomed cylindrical battery case 16 in which nickel is plated with iron (the outer surface of the bottom surface is a negative electrode external terminal). Then, battery case 1
A vibration isolating ring 18 was inserted into the upper inner peripheral side of 6, 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. After this, the battery case 16
An electrolytic solution consisting of a 30% by weight aqueous solution of potassium hydroxide (KOH) was injected therein. Next, the sealing body 17 was disposed above the opening of the battery case 16. In addition, the sealing body 1
7 is a lid 1 having a circular downward projection formed on the bottom surface.
7a, a positive electrode cap (positive electrode external terminal) 17b, and a valve body including a spring 17c and a valve plate 17d interposed between the lid 17a and the positive electrode cap 17b. A hole is formed.

As described above, the sealing member 17 is connected to the battery case 16.
After one electrode W1 is disposed on the upper surface of the positive electrode cap (positive external terminal) 17a, the other welding electrode W2 is disposed on the lower surface of the bottom surface (negative external terminal) of the battery case 16. 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 24 V is applied between the welding electrodes W1 and W2 in the discharge direction of the battery, and 3 KA is applied. About 15
An energization treatment was performed to flow for msec. As a result of this energization process, current concentrates on the contact portions between the bottom surface of the sealing body 17 and the three projections 23 formed on the top surface of the positive electrode current collector 20, and these three projections The contact portions between 23, 23, 23 and the bottom surface of the sealing body 17 were welded to form welded portions. 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.

Next, an insulating gasket 19 is fitted around the peripheral edge of the sealing body 17, and a pressing force is applied to the sealing body 17 using a press machine until the lower end of the insulating gasket 19 reaches the position of the recess 16a. Was pushed into the battery case 16. After that, the opening edge of the battery case 16 is crimped inward to seal the battery, and the battery has a nominal capacity of 6.0 as shown in FIG.
A 5 Ah cylindrical nickel-metal hydride battery was produced. The nickel-hydrogen storage battery of Example 2 thus manufactured was referred to as Battery B.

3. Comparative Example As shown in FIG. 6, a plurality of openings were formed in a positive electrode core exposed on the upper end surface of a spiral electrode group manufactured in the same manner as in Example 1 described above, and a lead portion 14b was extended from a part thereof. The disk-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 is welded to the negative electrode core exposed at the lower end surface of the spiral, thereby forming a spiral electrode 10.
a was produced. The electrode body 10a is housed in a battery case 16, and the negative electrode current collector 15 is spot-welded to the inner bottom surface of the battery case 20 (note that in FIG.
Although it seems that there is no space for inserting the welding electrode at the center of Oa, FIG. 6 is a view schematically showing
Actually, there is a space for inserting the 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 concave portion 16 a at the upper end of the vibration isolating ring 18.

Next, after the lead portion 14b extending from the positive electrode current collector 14a is vertically bent, the lead portion 14b is bent.
b was resistance-welded to the bottom of the sealing body 17 at the end. Then
The battery case 16 contains 30% by weight of potassium hydroxide (KO).
H) After injecting an electrolytic solution consisting of an aqueous solution, the lead portion 14
b was bent, and a sealing body 17 having an insulating gasket 19 fitted on the periphery thereof was arranged at the opening of the battery case 16. Then, the battery was sealed by caulking the opening edge of the battery case 16 inward to produce a cylindrical nickel-hydrogen storage battery having a nominal capacity of 6.5 Ah. The nickel-hydrogen storage battery of the comparative example thus manufactured was designated as Battery X.

4. Battery Characteristics Test (1) Activation Using the batteries A and B of the example produced as described above and the battery X of the comparative example, at room temperature (ambient temperature 25 ° C.)
After charging for 8 hours at a current value of 50 mA (0.1 C), 1
After a pause, the battery was discharged at a current value of 1300 mA (0.2 C) until the battery voltage reached 0.8 V. The charge / discharge cycle was repeated 10 times to activate the battery. .

(2) IV Characteristics Test Next, using the batteries A and B of Examples 1 and 2 and the battery X of the comparative example activated as described above, 1300 mA at room temperature (ambient temperature 25 ° C.) The battery in a state of being discharged until the battery voltage reaches 0.8 V at the current value of (2C) is 1300
The battery was charged at a current value of mA (0.2 C) for 3 hours. After a pause of 1 hour, the battery was discharged at a current value of 25 A for 30 seconds, and the battery voltage was measured 10 seconds after the start of discharging. Next, after charging the electric power for the discharged capacity, similarly, 50A,
Discharge was performed at a current value of 70 A and 100 A for 30 seconds, and the battery voltage was measured 10 seconds after the start of discharge. The thus obtained battery voltage 10 seconds after the start of discharge is plotted on the vertical axis, and each current value is plotted on the horizontal axis.
), The result is as shown in FIG.

As is clear from FIG. 7, the battery X of the comparative example
Examples 1 and 2 have a large slope of the IV line
It can be seen that the slopes of the IV lines of the batteries A and B are small. This indicates that the operating voltages of the batteries A and B of Examples 1 and 2 are all high and the internal resistance of the batteries is low.
This is because the batteries A and B of Examples 1 and 2 have a projection 33 on the lower surface of the sealing body 30, and the projection 33 and the positive electrode current collector 1
4 Since the contact portion with the upper surface is directly welded, or the projection portion 23 is provided on the upper surface of the positive electrode current collector 20 and the contact portion between the projection portion 23 and the lower surface of the sealing body 17 is directly welded. It is considered that the internal resistance at the contact portion was reduced and high output characteristics were obtained.

The above-described embodiment (Examples 1 and 2)
In, 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,
A contact portion between the projection 33 of the sealing body 30 and the upper surface of the positive electrode current collector 14 or a projection 23 of the positive electrode current collector 20 and the sealing body 17
The example in which the opening of the battery case 16 is sealed with the sealing body 30 (17) after the contact portion with the lower surface is welded, but after the opening of the battery case 16 is sealed with the sealing body 30 (17), Positive electrode cap 35 (17b) and battery case 1
6, a voltage is applied between the bottom surface of the positive electrode current collector 14 and a contact portion between the projection 33 of the sealing body 30 and the top surface of the positive electrode current collector 14, or the projection 23 and the sealing body. 17
Similar results were obtained when the contact portion with the lower surface was welded.

The above embodiment (Examples 1 and 2)
In the above, the discharge direction of the battery is between the positive electrode cap (positive external terminal) and the bottom surface of the battery case (negative external terminal).
Welding was performed by applying a voltage of 4 V and applying a current of 3 KA for about 15 msec. However, there is no correlation between the directions of the current applied to the battery, and the direction of the discharge is the same as that of the battery. Also obtained similar results. The applied current value is 300 A regardless of the size of the battery.
The same effect was obtained as described above. Note that a DC or AC power supply can be used as a power supply for a welding current flowing between the battery case and the sealing body in the welding process.

However, when an excessively large current is applied, even if the current is applied for a short time, each of the projections 33 or 2
3 is blown, and the current value to be blown varies depending on the material and shape of the sealing body or the current collector. Therefore, the current value needs to be 300 A or more and a value that does not blow the protrusions 33 or 23. is there. Further, the same effect can be obtained if the application time is 0.25 msec or more. However, if the application is performed for a long time as long as 1 second, each of the projections 33 or 23 is undesirably melted.

The above-described embodiment (Examples 1 and 2)
In, current flows between the positive electrode external terminal (positive electrode cap) and the negative electrode external terminal (bottom surface of the battery case) to weld the sealing body and the current collector and to form the negative electrode current collector and the inner bottom surface of the battery case. Was described at the same time, but after spot welding the negative electrode current collector and the inner bottom surface of the battery case, the positive external terminal (positive cap) and the negative external terminal (bottom surface of the battery case) Apply current between
The sealing member and the current collector may be welded. In this case, it is necessary to provide a space for welding electrode insertion at the center of the spiral electrode body, and this space may be formed by the core space when the spiral electrode group is formed.

Further, in the above embodiment,
Although an example has been described in which the sealing body is a positive terminal and the battery case is a negative terminal, the sealing body may be a negative terminal and the battery case may be a positive 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. Clearly what you can do.

[Brief description of the drawings]

FIG. 1 is a view showing a sealing body of the present invention, and FIG.
FIG. 1B is a bottom view, and FIG. 1B is a side view and a cross-sectional view with a part thereof cut away.

FIG. 2 is a cross-sectional view showing a state where 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.

FIG. 4 is a view showing an electrode body to which the current collector of the present invention is welded, FIG. 4 (a) is a top view thereof, FIG. 4 (b) is a side view thereof, and a sectional view in which a part thereof is cut away. It is.

5 is a sectional view showing a nickel-hydrogen storage battery formed by welding a sealing body to the current collector of FIG.

FIG. 6 is a cross-sectional view showing a storage battery of a conventional example (comparative example) and showing a state where a lead portion is welded to a sealing body.

FIG. 7 is a diagram showing a voltage (V) -current (I) characteristic 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 current collector (Example 1), 15 ... Negative electrode current collector, 16 ... Battery case (negative electrode external terminal), 16a ...
Groove part, 17 ... sealing body (Example 2), 17a ... lid body, 17
b: 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

 ────────────────────────────────────────────────── ─── Continuing from the front page (72) Inventor Takaaki Ikemachi 2-5-5 Keihanhondori, Moriguchi-shi, Osaka F-term (reference) in Sanyo Electric Co., Ltd. 5H011 AA03 AA04 CC06 DD13 FF02 GG02 JJ12 5H022 AA04 BB01 BB03 BB08 BB16 BB19 CC02 CC22 5H028 AA01 AA07 BB04 BB05 CC07 CC08 CC10 CC12

Claims (11)

[Claims] 1. A battery case having an opening serving also as one terminal, a sealing body sealing the opening serving as a terminal of the other electrode, and at least one of a positive electrode and a negative electrode housed in the battery case. And an electrode body having a current collector connected to an end of the battery, wherein at least one projection is provided on a lower surface of the sealing body, and the projection and the current collector are fixedly connected to each other. Storage battery. 2. The storage battery according to claim 1, wherein the protrusion is formed at a vertex of an equilateral triangle whose center is the center of the lower surface of the sealing body. 3. A battery case provided with an opening serving also as one terminal, a sealing body sealing the opening serving as a terminal of the other electrode, and at least one of a positive electrode and a negative electrode housed in the battery case. A current collector is connected to an end of the current collector, comprising: at least one protrusion on an upper surface of the current collector, wherein the protrusion and the sealing body are fixedly connected. Storage battery. 4. The storage battery according to claim 3, wherein the protrusion is formed at a vertex of an equilateral triangle whose center is the center of the upper surface of the current collector. 5. An electrode body having a current collector connected to at least one end of a positive electrode and a negative electrode is accommodated in a battery case having an opening serving also as a terminal of one electrode. What is claimed is: 1. A method for manufacturing a storage battery which is formed by sealing with a sealing body also serving as a terminal of a pole, wherein at least one protrusion is formed on a lower surface of the sealing body, and an electrolyte is injected into the battery case. An injecting step, an arranging step of arranging the sealing body in an opening of the battery case, and a current flowing between the battery case and the sealing body, and a contact portion between the protrusion and the upper surface of the current collector. And a sealing step of sealing the sealing body with an opening of the battery case. 6. An electrode body having a current collector connected to at least one end of a positive electrode and a negative electrode is accommodated in a battery case having an opening serving also as a terminal of one electrode. A method of manufacturing a storage battery formed by sealing with a sealing body also serving as a terminal of a pole, wherein: a protrusion forming step of forming at least one protrusion on an upper surface of the current collector; and an electrolyte solution in the battery case. An electrolyte injecting step of injecting, an arrangement step of disposing the sealing body in an opening of the battery case so that the current collector and the sealing body are in contact with each other, and the battery case and the sealing body. And a welding step of welding a contact portion between the lower surface of the sealing body and the projection by passing a current between the sealing body and a sealing step of sealing the sealing body to an opening of the battery case. A method of manufacturing a storage battery. 7. The method according to claim 5, wherein in the welding step, the sealing body is pressurized toward the current collector, and a current flows between the battery case and the sealing body. A method for manufacturing the storage battery according to claim 6. 8. An electrode body having a current collector connected to at least one end of a positive electrode and a negative electrode is accommodated in a battery case having an opening serving also as a terminal of one electrode. What is claimed is: 1. A method for manufacturing a storage battery which is formed by sealing with a sealing body also serving as a terminal of a pole, wherein at least one protrusion is formed on a lower surface of the sealing body, and an electrolyte is injected into the battery case. An injecting step, an arranging step of arranging the sealing body in an opening of the battery case so that the current collector and the sealing body are in contact with each other, and placing the sealing body in an opening of the battery case. A storage battery, comprising: a sealing step of sealing; and a welding step of flowing a current between the battery case and the sealing body to weld a contact portion between the protrusion and the upper surface of the current collector. Manufacturing method. 9. The method according to claim 9, wherein, in the sealing step, the sealing body is pressed toward the current collector to bring the projection on the lower surface of the sealing body into close contact with the current collector. A method for manufacturing the storage battery according to claim 8. 10. An electrode body having a current collector connected to at least one end of a positive electrode and a negative electrode is accommodated in a battery case having an opening serving also as a terminal of one electrode. A method of manufacturing a storage battery formed by sealing with a sealing body also serving as a terminal of a pole, wherein: a protrusion forming step of forming at least one protrusion on an upper surface of the current collector; and an electrolyte solution in the battery case. An electrolyte injecting step of injecting, an arrangement step of arranging the sealing body in an opening of the battery case so that the current collector and the sealing body are in contact with each other, And a welding step of welding a contact portion between the lower surface of the sealing body and the projection by passing a current between the battery case and the sealing body. A method of manufacturing a storage battery. 11. The method according to claim 10, wherein, in the sealing step, the sealing body is pressed against the current collector to bring the lower surface of the sealing body into close contact with the projection. A method for manufacturing the storage battery according to the above.