JP2005190837A - Sealed storage battery - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a switch incorporation type secondary battery capable of always stably providing high charge accepting performance. <P>SOLUTION: This sealed storage battery is so structured that a battery can 5 with an electrode 10 stored inside together with an alkaline solution is sealed by a metallic lid 2, a gasket 6 and a connection terminal 9 inserted into a holding part 6c formed on the gasket; a cap 1 doubling as a positive electrode terminal or a negative electrode terminal is mounted on the lid 2; and is provided with a switch mechanism S for carrying and cutting off a charge current by moving the connection terminal 9 in conjunction with expansion and constriction operation of a spring member 4 disposed in the cap 1 in response to change of battery internal pressure to bring a switch plate 8 jointed to the connection terminal 9 into contact with and separate it from the lid 2. The lid 2 is jointed to the cap 1 by welding, the connection terminal 9 is formed into a rod-like shape, and a lock mechanism is formed between the rod-like connection terminal and the holding part 6c. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an improvement in a sealed storage battery provided with a pressure switch mechanism that cuts off a charging current in accordance with a change in battery internal pressure during charging.

  Secondary batteries used as power sources for portable devices include nickel-cadmium batteries, small sealed lead batteries, lithium ion batteries, and the like. These storage batteries are charged by a charging method suitable for the charging characteristics of each battery. For example, a nickel-cadmium battery is charged with a constant current, and the charging current is controlled by detecting a battery voltage drop characteristic that occurs at the end of charging. In a small sealed lead battery and a lithium ion battery, after charging at a constant current, the charging current is controlled when a constant voltage is reached.

  In alkaline storage batteries such as nickel-metal hydride storage batteries and nickel-cadmium storage batteries, there has been an increasing demand for rapid charging, which has not been achieved in the past, such as completing charging within 30 minutes. Conventionally, nickel-metal hydride storage batteries perform the same charge control as nickel-cadmium batteries, but if you try to perform a quick charge like the one described above, heat generation and gas generation occur during charging. Or the internal pressure of the battery is increased, the gas discharge valve is operated, and the electrolyte is discharged together with the gas. Therefore, the battery performance may be deteriorated, and it is difficult to realize rapid charging.

  As described above, when a nickel hydride storage battery is to be rapidly charged, for example, at a constant voltage, it is accompanied by an increase in battery temperature and an increase in internal pressure of the battery. Thus, in particular, a sealed storage battery having a pressure switch mechanism that cuts off a charging current in accordance with a change in the pressure inside the battery has been proposed by paying attention to an increase in pressure inside the battery at the time of charging (for example, Patent Documents). 1).

  In a sealed storage battery equipped with such a pressure switch mechanism, when the battery internal pressure reaches a constant pressure during charging, the charging current is cut off, and when the battery internal pressure falls below a certain pressure, the battery is connected again. Since the pulse charging is performed in conjunction with the change of the battery, an increase in battery temperature during charging is suppressed. The configuration is shown in FIG. 11, for example.

In the example of FIG. 11, reference numeral 21 is a cap (positive electrode terminal), 22 is a lid (second terminal of the pressure switch), 23 is rubber, 25 is a battery case (negative electrode terminal), 26 is a gasket, 27 is a lead member, 28 is a switch plate (first terminal of a pressure switch), 29 is a connection terminal, 30 is one of a positive electrode and a negative electrode, and an alkaline solution (not shown) is placed in the battery case 25 containing the electrode 30. ), And the battery case can 25 is sealed (sealed) by the gasket 26, and the rubber 23 is deformed in accordance with the change in the internal pressure (battery internal pressure), whereby the first terminal of the pressure switch The charging current is cut off by 28 being in contact with and separating from the second terminal 22.
US Patent Application Publication No. 2002 / 0119364A1

  In the conventional sealed storage battery shown in FIG. 11, the connection terminal 29 is not rod-shaped, but has a protrusion 31 at one end (the lower end in FIG. 11), and is larger than the opening diameter of the lid 22 on the lid 22. A switch plate 28 having a diameter is joined to the side wall of the connection terminal 29. Therefore, before joining the switch plate 28 to the connection terminal 29, it is necessary to insert the connection terminal 29 into the holding portion of the gasket 26. When the lid 22 and the cap 21 are joined by welding, the existence of the gasket 26 is required. It is very difficult to join the two. In a conventional sealed battery with a built-in pressure switch, as shown in FIG. 11, the cap 21 and the lid 22 are overlapped with each other at the peripheral edge and locked in a locking groove formed in the gasket 26. It is pinched in a state.

  In the case of the conventional sealed storage battery shown in FIG. 11, it is sufficient that the alignment of the joint surface between the cap 21 and the lid 22 is poor or that foreign matter such as dust or dust is present on the joint surface during assembly. As a result, it is difficult to obtain a proper contact state, resulting in a large contact resistance, and there is a problem that the charge acceptance performance is deteriorated when rapid charging is performed.

  In addition, sealing accuracy (sealing performance) may be deteriorated due to poor alignment during assembly or the presence of foreign matter on the joint surface. If the sealing accuracy is lowered, problems such as gas leaking to the outside or alkali solution leaking are likely to occur.

  In addition, the battery temperature rises during charging, but the rubber 23 applied as a resilient member softens when the temperature becomes high, and the load characteristics deteriorate. Therefore, particularly in charging under a high environmental temperature, the rubber 23, the change in the load characteristic is remarkable, and the charging current switching timing is disturbed, and the switch function of the pressure switch may be deteriorated.

  Further, when the switch plate (first terminal of the pressure switch) 28 moves up and down in response to the expansion / contraction operation of the rubber 23, the switch plate 28 tilts with respect to the lid (second terminal of the pressure switch) 22, and the pressure switch Since the contact / separation operation between the first terminal 28 and the second terminal 22 may be incomplete, the pressure switch function has a low reliability.

  The present invention has been made in view of such circumstances, and is a sealed storage battery with a built-in pressure switch, which can provide a stable and high charge acceptance performance and a highly reliable pressure switch function. The purpose is to do.

(1) The sealed battery according to the present invention is sealed by a rod-shaped connection terminal in which a battery case can containing an electrode together with an alkaline solution is inserted into a metal lid, a gasket, and a holding portion provided in the gasket, A cap also serving as a positive electrode terminal or a negative electrode terminal is mounted on the lid, and the rod-shaped connection terminal moves in conjunction with the elastic member disposed in the cap expanding and contracting in response to a change in the battery internal pressure. , A sealed storage battery having a switch mechanism (S) for switching the charging current by connecting and disconnecting the switch plate and the lid joined to the connection terminal,
The lid and the cap (1) are joined by welding, and a locking mechanism is provided between the rod-like connection terminal and the holding portion. In addition, a rod-shaped connection terminal here means the metal rod-shaped body which does not provide a convex part in a side wall.

  According to this configuration, the switch plate is joined to the rod-like connection terminal, the lid and the cap are arranged so as to surround the switch plate, and the two are welded together, and finally the rod-like connection terminal is held by the gasket. Since there is no gasket in the process of joining the lid and the cap, it is possible to easily join the two. In addition, since a locking mechanism is provided between the rod-like connection terminal and the gasket holding portion, the rod-like connection terminal is detached from the gasket holding portion even if the internal pressure of the battery rises and pressure is applied to the rod-like connection terminal and the gasket. Never leave.

  By joining the lid and the cap by welding, the joining state is good, and the occurrence of poor joining between the two members can be avoided. Thereby, since the electrical resistance in a junction part can be decreased, the charge acceptance performance when performing a quick charge improves.

  By integrating the lid and cap in advance by welding, the efficiency of assembly work can be remarkably improved, the assembly accuracy can be improved stably, and foreign matters such as dust and dirt are present on the joint surface. Therefore, high sealing accuracy (sealing performance) can be stably maintained. This makes it difficult for gas leaks and liquid leaks to occur.

(2) A sealed battery according to the present invention is the sealed battery according to (1), in which the cap and the cap are fixed to the outer surface of the lid by joining with the lid, and only the peripheral portion of the lid. Is locked inside the open end of the battery case can through a gasket.

  With the configuration described in (2), the electrical resistance of the contact portion between the lid and the cap can be reduced as in the case of (1), and the peripheral edge of the lid is held between the inner peripheral portions of the gasket. Thus, the dimensional accuracy of the seal (hereinafter referred to as “crimp seal”) can be increased, and a sealed battery having an excellent sealing function can be obtained. In addition, since only one plate member (lid) is locked in the locking groove of the gasket, the thickness of the seal portion of the crimp seal is reduced compared to the case where the plate and the cap are stacked and overlapped. The height can be increased, and the battery capacity can be increased.

(3) The sealed storage battery according to the present invention is the sealed storage battery according to (1) or (2), wherein the elastic member (4) is made of a metal material.

  With the configuration described in (3) above, since the elastic member is less likely to deteriorate than the elastic elastic member and the load characteristics are stable, the battery is always affected without being affected by environmental changes. The expansion / contraction operation is appropriately performed according to the change of the internal pressure, and a highly reliable pressure switch function can be obtained.

(4) The sealed storage battery according to the present invention is the sealed storage battery according to (1) to (3) above, wherein the opening edge of the lid serves as one terminal of the switch, and the outer peripheral edge 8 of the switch plate. Becomes the other terminal, and a rod-like connection terminal for connecting the switch plate and the electrode group is held through the gasket, and the switch plate is fixed to a portion of the rod-like connection terminal protruding toward the battery cap. At the same time, the holding portion of the gasket holding the rod-like connection terminal is inserted in a sliding contact state with respect to the opening formed in the lid.

  With the configuration described in (4) above, the gasket holding portion is fitted and inserted into the opening formed in the lid in a slidable state. For example, between the holding portion and the opening. Gas leakage and liquid leakage can be more effectively prevented by setting the outer diameter of the holding portion and the inner diameter of the opening to such an extent that the sealing performance can be secured. And since the holding part of the gasket holding the rod-shaped connection terminal operates in a sliding contact state with the opening of the lid, the holding part of the gasket and the switch plate interlocked therewith can be easily translated without being inclined. In addition, the contact between the switch plate and the lid is improved, and the contact and separation between the two are ensured, so that a switch function with high reliability can be achieved.

(5) A sealed storage battery according to the present invention is the battery according to any one of (1) to (4), wherein the elastic material is insulated from an outer peripheral edge portion of a switch plate which is one terminal of the switch. It makes it contact | abut through a member, It is characterized by the above-mentioned.

  With the configuration described in (5) above, since the pressing force of the elastic material acts on the outer peripheral edge portion of the switch plate, the switch plate is prevented from being inclined with respect to the lid, Contact and separation are ensured, and a highly reliable switch function can be achieved.

  In the sealed battery with a built-in pressure switch according to the present invention, the lid and the cap are joined by welding, so that the joining state is good and the occurrence of poor joining between the two members can be avoided. Since the electrical resistance in the battery is reduced, the charge acceptance performance is improved when rapid charging is performed.

  Also, by integrating the lid and cap in advance by welding, the efficiency of the assembly work can be significantly improved, the assembly accuracy can be improved stably, and foreign matters such as dust and dirt can be joined. Therefore, high sealing accuracy (sealing performance) can be stably maintained without increasing the electrical resistance. As a result, gas leakage or liquid leakage is less likely to occur, and high charge acceptance performance can be stably maintained.

  The holding portion of the gasket holding the rod-like connection terminal is inserted in sliding contact with the opening formed in the lid, or the elastic material is attached to the outside of the switch plate which is one terminal of the switch. By contacting the peripheral edge with an insulating member, the switch plate can be easily moved in parallel without being inclined with respect to the lid. Separation is ensured and a highly reliable switch function can be achieved.

  The sealed storage battery according to the best embodiment of the present invention will be described below in detail with reference to the drawings.

[Embodiment 1]
FIG. 1 is a vertical cross-sectional view of a main part for explaining the configuration of a sealed storage battery with built-in pressure switch (hereinafter referred to as a sealed storage battery) according to the first embodiment. In addition, a battery case (also serving as a negative electrode terminal) 5 containing the electrode 10 together with an alkaline solution (not shown) is provided with a metal lid 2, a gasket 6 and a gasket 6 made of a synthetic resin molding such as polypropylene or polyamide. It is sealed with a rod-like connection terminal 9 inserted through the provided holding portion 6c. By adopting the rod-like connecting terminal 9 as described above, the lid 2 and the cap 1 can be easily joined. As shown in FIG. 1, the cap 1 serving also as the positive electrode terminal is provided on the upper surface of the lid 2, for example. They are joined by spot welding or ring projection welding. In the cap 1, a disc spring (which urges the switch plate 8 constituting the switch mechanism S for switching the charging current in response to a change in the battery internal pressure so as to be able to come in contact with and separate from the base lid 2 ( The elastic member 4 of the present invention is disposed.

  Thus, since the lid 2 and the cap 1 are joined by welding, the joining state is ensured and the occurrence of poor joining can be avoided, and the electrical resistance at the joining portion (welded portion of the present invention) 3 is reduced. Charge acceptance performance is improved when rapid charging is reduced. Further, by integrating the lid 2 and the battery cap 1 by welding in advance, the efficiency of the assembly work can be remarkably improved, and the assembly accuracy can be improved stably, and foreign matter such as dust and dirt can be obtained. Can be avoided. Therefore, high sealing accuracy (sealing performance) can be stably maintained, and problems such as gas leakage and liquid leakage are less likely to occur. The number of joint points when the cap 1 and the lid 2 are joined by spot welding is not particularly limited, but in order to keep the mechanical strength strong and the electrical resistance between the cap 1 and the lid 2 small, the number of joint points is set. At least 4 points are preferable, and 6 points or more are more preferable.

  A thin portion 6f is provided on the peripheral edge of the holding portion 6c of the gasket 6 to provide flexibility. When the internal pressure of the battery increases during charging, the thin portion bends, the connection terminal 9 and the switch plate 8 move upward in the figure, and the peripheral edge 8b (S2) of the switch plate 8 and the inner edge 2b (S1) of the lid 2 And the circuit is turned off. When the internal pressure of the battery drops, the rod-like connection terminal 9 and the switch plate 8 are moved downward by the pressing force of the elastic member 4, and the peripheral edge portion 8b (S2) of the switch plate 8 and the inner edge portion 2b (S1) of the lid 2 are brought into contact. The circuit turns on. By forming the disc spring 4 as a resilient member with a metal material, the load characteristic is stabilized as compared with the case of using rubber as in the conventional case, and it is less affected by environmental changes such as ambient temperature. Thus, the expansion / contraction operation is appropriately performed according to the change in the internal pressure of the battery, the on / off operation of the pressure switch mechanism S is stabilized, the charging current switching timing is normally maintained, and the charge acceptance performance is stably improved. Moreover, since the space in the cap 1 can be effectively utilized by arranging the bullet member 4 in the cap 1, it is not necessary to secure a space for arranging the bullet member 4 separately. There is an advantage that the degree of freedom of layout is improved.

  The whole will be described in detail. On the upper peripheral edge of the battery case can 5, a concave groove part 5a for tightly fitting the peripheral part of the gasket 6 made of an insulating material is formed. A flange portion 1 a formed outwardly at the lower portion of the battery cap 1 formed in the above is disposed at a position inside the inner peripheral portion 6 a of the gasket 6, and the flange portion 1 a is attached to the disc-shaped lid 2. For example, it is possible to weld with good workability by spot welding or the like. A degassing hole h is formed in the side wall surface of the battery cap 1 so that the gasket 6 can be deformed without difficulty according to the change in the internal pressure of the battery.

  A locking groove 6b is formed in the inner peripheral portion 6a of the gasket 6, and only the peripheral edge portion of the lid 2 is locked in the locking groove 6b. In this way, since only one plate member (lid 2) is locked in the locking groove 6b, the battery case can 5 is formed deeper than in the case of locking by the conventional two-sheet alignment shown in FIG. It is possible to increase the charging capacity (battery capacity). Moreover, since the assembly accuracy is stabilized, it becomes easy to ensure high sealing performance and to maintain the sealing performance.

  In the through hole 6d of the cylindrical holding portion 6c formed at the center of the gasket 6, for example, a rod-shaped connection terminal 9 formed in a columnar shape is integrally fitted and fixed, and the lower portion of the lead wire 7 is connected to the lower portion. To the electrode group 10. On the other hand, a disc-shaped switch plate (the other terminal) 8 with a hole is fixed to the upper portion of the rod-like connection terminal 9 protruding from the through hole 6d, and the upper portion of the rod-like connection terminal 9 and the upper surface of the switch plate 8 are An insulating member 11 is fitted, the biasing end of the disc spring 4 abuts against the insulating member 11 in a pressed state, and the switch plate 8 and the rod-like connection terminal 9 are insulated from the battery cap 1, and the insulating member The urging end of the disc spring 4 is in contact with 11. The disc spring 4 may be arranged upside down. Further, instead of the disc spring 4, a coil spring or a plate spring may be used.

  A circular hole (opening of the present invention) 2a is formed at the center of the lid 2 locked in the locking groove 6b of the gasket 6, and the holding part 6c of the gasket 6 has a predetermined gap in the circular hole 2a. The gasket 6 is freely deformed in accordance with the change in the internal pressure of the battery, and the switch plate 8 is allowed to be displaced in the vertical direction together with the gasket 6. The opening 2a of the present invention is not limited to a circular hole, and may be an ellipse or a square (rectangular, square, etc.).

  Further, on the upper surface of the gasket 6, a notch-shaped safety valve (notch portion of the present invention) 6 e that makes it easy to generate a crack to protect the battery case 5 when the battery internal pressure suddenly rises is provided. When the internal pressure of the battery suddenly increases during charging, the gasket 6 can be cracked from the safety valve 6e, and the gas can be released to the outside from the small hole h of the battery cap 1. Thus, the battery case can 5 can be prevented from being deformed or damaged, and the safety can be improved.

  In this embodiment, the pressure switch mechanism S for switching off the charging current is provided between the cap 1 and the lid 2, and the pressure switch mechanism S is a dish provided in the cap 1. It comprises a flat switch plate (first terminal of the present invention) 8 urged by a spring 4 and a flat cover (second terminal of the present invention) 2. More specifically, the switch plate 8 is joined to an upper portion of a rod-like connection terminal 9 inserted through a through hole of a holding portion 6 c provided in the center portion of the gasket 6, and a screw is attached to the lower end of the rod-like connection terminal 9. The rod-like connection terminal 9 is engaged with the holding portion 6c so that the rod-like connection terminal 9 is not detached from the holding portion 6c even if the nut-like metal member 12 is attached to the screw and the internal pressure of the battery rises. It has been stopped.

  The rod-shaped connection terminal 9 is connected to an electrode 10 (positive electrode) via a deformable lead wire 7, and the upper end portion of the rod-shaped connection terminal 9 and a part of the switch plate 8 are insulated members as described above. 11 and the outer peripheral edge 8b outside thereof is the first terminal. On the other hand, the lid 2 is cut out in a circular shape at the inner side of the welded portion 3, and the peripheral edge (opening edge of the present invention) 2b of the circular hole 2a becomes the second terminal.

  With such a configuration, when the battery internal pressure is low, as shown in FIG. 1, the outer peripheral edge 8 b of the switch plate 8 comes into contact with the peripheral edge 2 b of the lid 2 and the pressure switch mechanism S is turned on, When the battery internal pressure exceeds a certain pressure, as shown in FIG. 2, the thin portion 6f of the gasket 6 bends upward, the outer peripheral edge 8b of the switch plate 8 moves away from the peripheral edge 2b of the base lid 2, and the switch mechanism S The charging current is cut off and the charging current is cut off, and pulse charging is performed in conjunction with the change in the internal pressure of the battery. In this way, since the charging current is controlled according to the change in the battery internal pressure, an increase in battery temperature can be suppressed, high charging efficiency can be obtained, and rapid charging becomes possible.

(Embodiment for locking the rod-shaped connection terminal and the holding portion)
As described above, the rod-like connection terminal here does not have a protruding portion on the side wall, and can be inserted into a through hole provided in the holding portion of the gasket. When the rod-like connection terminal is applied, when the internal pressure of the battery rises, the rod-like connection terminal 9 may be detached from the holding portion 6c provided on the gasket due to the internal pressure. It is desirable to provide a mechanism for locking to. In the present invention, the form of locking between the rod-like connection terminal 9 and the holding portion 6c is not particularly limited. In addition to a method in which a screw is cut at the lower end of the rod-like connection terminal 9 as shown in the first embodiment and a nut-like metal member is attached to the screw by screwing, for example, a switch as shown in FIG. A method of fitting the claw of the claw-like member 13 attached to the plate 8 into a recess provided on the outer wall of the holding portion 6c, and further, as shown in FIG. 4, a metal ring 14 is fitted around the holding portion 6c, As shown in FIG. 5, a taper is provided on the side of the rod-like connecting terminal 9 so that the diameter becomes larger as it is closer to the lower end of the drawing, or the connecting terminal 9 is made a simple rod-like shape as shown in FIG. By increasing the frictional force between the holding portion 6c and the connecting terminal 9 by a method of fitting by making the inner diameter of the through hole smaller than the outer diameter of the connecting terminal 9 (fitting method by tight fitting), the connecting terminal 9 is held by the holding portion. Detach from 6c How to prevent can also be applied.

[Embodiment 2]
In the second embodiment, as shown in FIG. 7, the cylindrical holding portion 6 c formed at the center of the gasket 6 is brought into a sliding contact state with the opening 2 a formed in the lid 2. The outer peripheral edge 8b of the switch plate 8 can be brought into contact with the peripheral edge 2b of the lid 2 in parallel with each other to improve the sealing performance. In addition, the same code | symbol is attached | subjected about the same or equivalent member as Embodiment 1, and the description is abbreviate | omitted.

  For example, by setting the outer diameter of the holding portion 6c and the inner diameter of the opening 2a so that the outer wall surface of the holding portion 6c comes into contact with the inner wall surface of the opening 2a, the sealing performance is improved and gas leakage and liquid leakage are further reduced. In addition, the opening 2a can act as a guide to stabilize the vertical displacement operation of the holding portion 6c that holds the connection terminal 9 (the holding portion 6d is not inclined and is not inclined). Therefore, the switch plate 8 can be reliably brought into and out of contact with the lid 2 and a highly reliable switch function can be obtained.

  Further, in the second embodiment, the disc spring which is the elastic material 4 is arranged as shown in FIG. 3 (the diameter on the side in contact with the cap 1 is small and the diameter on the side in contact with the switch plate 8 via the insulating member 11). Since the pressing force of the disc spring acts on the outer peripheral edge 8 b of the switch plate 8, the switch plate 8 can be prevented from being inclined with respect to the lid 2. As a result, the contact and separation of the switch plate 8 with respect to the lid 2 are ensured, and a highly reliable switch function can be obtained.

  In the second embodiment, the state in which the battery internal pressure has increased is basically the state shown in FIG. 2 (the state in which the outer peripheral edge 8b (S2) of the switch plate 8 and the opening edge 2b (S1) of the lid 2 are separated). They are the same and are not shown. Further, the opening 2a of the present invention is not limited to a circular hole, but may be an ellipse or a square (rectangular, square, etc.), as in the first embodiment.

[Embodiment 3]
In the third embodiment, as shown in FIG. 8, a spiral conical coil spring is applied as the elastic material 4 in the second embodiment. The conical coil spring has a larger diameter at one end than the diameter at the other end. By using the conical coil spring, it is possible to avoid the overlapping of the wires constituting the spring in the vertical direction, thereby reducing the thickness of the spring. It is effective to do. Similarly to the second embodiment, the conical coil spring is arranged such that one end having a large diameter is arranged on the switch plate 8 side so that the pressing force of the coil spring acts on the outer peripheral edge 8 b of the switch plate 8. The switch plate 8 can be prevented from being inclined with respect to the lid 2, the switch plate 8 can be reliably brought into contact with and separated from the lid 2, and a highly reliable switch function can be obtained.

  As in the second and third embodiments, the holding portion 6c is inserted into the opening 2a formed in the lid 2 so as to be in sliding contact with the disc spring or the conical coil spring. In the embodiment of the present invention by combining one end having a large diameter on the switch plate 8 side and directing the pressing force of the coil spring to act on the outer peripheral edge 8b of the switch plate 8. The switch plate can be stably moved in the vertical direction. Also in the case of the first embodiment, the switch plate 8 is provided by disposing the conical coil spring in the same manner as in the second and third embodiments. Needless to say, it is possible to prevent the switch 2 from being inclined with respect to the lid 2, and the switch plate 8 is reliably brought into and out of contact with the lid 2, and a highly reliable switch function can be obtained.

(Example)
A nickel electrode (positive electrode) and a hydrogen storage alloy electrode (negative electrode) are laminated via a separator, and the laminate is wound to form a wound electrode plate group, and the electrode plate group is applied to a sealed type with a rated capacity of 1700 mAh. A nickel-metal hydride storage battery having the configuration shown in FIG. 1 (the battery cap 1 is joined to the lid 2 by welding and only the lid 2 is locked in the locking groove 6b of the gasket 6), and a pressure switch (S ) 10,000 AA-sized storage batteries having an operating pressure of 2.4 MPa were produced. All the batteries produced were allowed to stand at room temperature and humidity for 1 week, and then a visual appearance inspection was performed to investigate the presence of liquid leakage and assembly failure. After removing 20 sample batteries from a storage battery that has been judged normal by visual inspection (a storage battery that has no leakage and is normally assembled), and after performing chemical conversion by a prescribed method, After charging for 16 hours at a temperature of 20 ° C. and 0.1 ItA, and letting it stand for 1 hour after charging, discharging was performed at the same temperature at a discharge rate of 0.2 ItA and a discharge cut voltage of 1.0 V to obtain a discharge capacity equal to the rated capacity. It was confirmed that Next, the sample battery was charged at a constant voltage for 15 minutes at an ambient temperature of 20 ° C. and a charge voltage of 1.65 V, left at the same temperature for 1 hour, and then discharged at a discharge rate of 0.2 ItA and a discharge cut voltage of 1.0 V. It was. The charge / discharge operation was repeated five times, and the ratio of the discharge capacity obtained by the fifth discharge to the rated capacity was used as an index for evaluating the charge acceptance performance in rapid charge.

(Comparative example)
11 (the cap 21 is not welded to the lid 22, and the cap 21 and the lid 22 are overlapped with each other at the peripheral edge thereof and locked in the locking groove of the gasket 26. In the cap. 10000 sealed nickel-metal hydride storage batteries having the same configuration as those of the example were manufactured, and the same investigation as in Example 1 was performed. Moreover, the sample battery 10 was extracted from the storage battery determined to be normal by visual appearance inspection, and subjected to the same charge / discharge test as that of the example. The sample battery after chemical conversion was charged at an ambient temperature of 20 ° C. and 0.1 ItA for 16 hours, left for 1 hour after charging, and then discharged at the same temperature at a discharge rate of 0.2 ItA and a discharge cut voltage of 1.0 V. As in the previous example, it was confirmed that a discharge capacity equal to the rated capacity was obtained.

実施例の密閉型ニッケル水素蓄電池においては、漏液のあった電池数、及び、不具合蓋のあった電池数も０であった。これに対して、比較例の密閉型ニッケル水素蓄電池では、キャップのフランジ部分の表面に漏液が認められた電池が１１個、蓋の組み付けに不具合が認められた電池が９個存在した。これは、比較例の密閉型ニッケル水素蓄電池では、電池キャップ２１と蓋２２が溶接されていないため、予め、これらを組み付けることができず、そのために、組付け不良による位置ずれや接合面への異物の介入等が発生し、封口精度にばらつきが発生したためであると考えられる。 (Visual appearance survey results)
Table 1 shows the results of visual inspection.

In the sealed nickel-metal hydride storage battery of the example, the number of batteries with leakage and the number of batteries with defective lids were also zero. On the other hand, in the sealed nickel-metal hydride storage battery of the comparative example, there were 11 batteries in which liquid leakage was observed on the surface of the flange portion of the cap and 9 batteries in which defects were found in the assembly of the lid. This is because in the sealed nickel-metal hydride storage battery of the comparative example, since the battery cap 21 and the lid 22 are not welded, they cannot be assembled in advance. This is considered to be due to the occurrence of foreign matter intervention, etc. and variations in sealing accuracy.

(Quick charge test results)
FIG. 9 shows the results of the quick charge test conducted under the above conditions. In FIG. 9, the horizontal axis represents the fifth discharge capacity {ratio to the rated capacity (%)}, and the vertical axis represents the number of batteries. As shown in FIG. 5, the sealed nickel-metal hydride storage battery of the comparative example has a considerably lower discharge capacity than the sealed nickel-metal hydride storage battery of the example, and further, the discharge capacity of 2 cells out of 10 cells is smaller. It was confirmed that it was extremely low. The capacity of the comparative example battery is generally lower than that of the example battery because the cap and the lid are not joined, so the contact resistance between them is large and the charge acceptance during quick charging is low. The discharge capacity of two of the 10 cells of the battery is low because the contact resistance between the cap and the lid is extremely large because the minority of the cap and lid cannot be confirmed by visual inspection. It is thought that it became.

  FIG. 10 shows an example of the temporal transition of the charging current and the battery temperature when the sealed nickel-metal hydride storage battery according to the embodiment is charged at a constant voltage. As shown in FIG. 10, the pressure switch operates in the steel sheet for charging, and pulse charging is performed while the pressure switch is operating, and further increase in battery temperature is suppressed. In the charging at the ambient temperature of 20 ° C. shown here, the pressure switch operated normally also in the comparative battery, but the battery temperature further increased at a high temperature such as an ambient temperature exceeding 30 ° C. As a result, the pressure switch does not operate normally, the pressure switch remains on, and the battery temperature may rise abnormally.

  In addition, although the size of the electrode plate was the same in the example and the comparative example, in the AA size sealed nickel-metal hydride storage battery according to the example, only the peripheral part of the lid was fitted in the locking groove of the gasket. Therefore, the depth of the battery case can be increased compared to the comparative battery in which both the cap and the lid are fitted in the locking grooves of the gasket, and the battery case depth is larger than the electrode plate width. There was a margin. In the case of the embodiment, the width (height in the figure) of the electrode plate can be increased by about 2% compared to the comparative example, and a storage battery having a large capacity corresponding to the width can be obtained.

It is sectional drawing which shows the structure of the sealed storage battery which concerns on Embodiment 1 of this invention. It is sectional drawing of the sealed storage battery which concerns on Embodiment 1 of this invention of a pressure switch being an OFF state. It is a figure which shows an example of the latching mechanism of the connection terminal of this first clear and the holding | maintenance part of a gasket. It is a figure which shows an example of the latching mechanism of the connection terminal of this first clear and the holding | maintenance part of a gasket. It is a figure which shows an example of the latching mechanism of the connection terminal of this first clear and the holding | maintenance part of a gasket. It is a figure which shows an example of the latching mechanism of the connection terminal of this first clear and the holding | maintenance part of a gasket. It is sectional drawing which shows the structure of the sealed nickel-metal hydride storage battery which concerns on Embodiment 2 of this invention. It is sectional drawing which shows the structure of the sealed storage battery which concerns on Embodiment 3 of this invention. It is a graph which shows the discharge capacity of the Example battery of this invention, and a comparative example battery. It is explanatory drawing which shows the charge characteristic of the Example and comparative example of this invention. It is sectional drawing which shows an example of a structure of the conventional pressure switch built-in type sealed storage battery.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Cap, 1a ... Outward flange, 2 ... Cover, 2b ... Opening edge, 3 ... Welded part, 4 ... Elastic member, 5 ... Battery case, 6 ... Gasket, 6a ... Inner peripheral part, 6b ... Locking Groove, 6c ... holding portion, 6e ... notch, 8 ... switch plate, 8b ... outer peripheral edge, 9 ... rod-like connection terminal, 10 ... electrode, S ... switch mechanism, S1 ... first terminal, S2 ... second terminal, h ... Small hole

Claims (5)

A battery-shaped can (5) in which the electrode (10) is housed together with an alkaline solution is inserted into a metal lid (2), a gasket (6), and a holding portion (6c) provided on the gasket. ), And the cap (1) serving as the positive electrode terminal or the negative electrode terminal is placed on the lid (2), and the elastic member (4) disposed in the cap (1) The rod-like connection terminal 9 moves in conjunction with the expansion / contraction operation according to the change, and the switch plate (8) and the lid (2) joined to the rod-like connection terminal (9) are brought into contact with and separated from each other. A sealed storage battery provided with a switch mechanism (S) for performing the disconnection,
The sealed storage battery, wherein the lid (2) and the cap (1) are joined by welding, and a locking mechanism is provided between the connection terminal (9) and the holding portion (6c).   The lid (2) and the cap (1) are fixed to the outer surface of the lid (2) by joining with the lid (2), and only the peripheral edge of the lid (2) is inserted through the gasket (6). The sealed storage battery according to claim 1, wherein the battery is locked inside the open end of the tank can (5).   The sealed storage battery according to claim 1 or 2, wherein the elastic member (4) is made of a metal material.   The opening edge (2b) of the lid (2) serves as one terminal (S1) of the switch (S), and the outer peripheral edge (8b) of the switch plate (8) serves as the other terminal (S2). 8) and a connection terminal (9) for connecting the electrode (10) are held through the gasket (6), and the switch is formed at a portion of the connection terminal (9) protruding toward the battery cap (1). The holding part (6c) of the gasket (6) holding the connection terminal (9) is fixed to the opening (2a) formed in the lid (2) while the plate (8) is fixed. The sealed storage battery according to claim 1, wherein the sealed storage battery is inserted in a sliding contact state. The elastic material (4) is in contact with an outer peripheral edge (8b) of a switch plate (8) which is one terminal (S2) of the switch (S) via an insulating member (11). The sealed storage battery according to claim 1.

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