JP2008071692A - Lead storage battery - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid type lead storage battery in which a sheet covering a liquid plug venthole is stuck on a lid in order to control liquid reduction and in which sticking between the sheet and the cover due to exuded liquid from the venthole, an abnormal rise of a battery inner pressure caused by the sticking and deformation of a battery case caused by the rise are prevented. <P>SOLUTION: In the storage battery in which a sheet covering a venthole provided on a liquid plug is stuck on a lid, a slit is formed in a position close to the venthole of the sheet. Even if a sticking occurs between the sheet and the lid due to exuded electrolyte solution, gas generated in the battery can be dispersed into an atmosphere through the slit. The slit is provided with each of the ventholes and it is recommended that a plurality of slits are provided with each of the ventholes. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a lead-acid battery.

  Lead-acid batteries are used for various purposes such as vehicle engine starting and backup power supply. Among them, the start lead-acid battery supplies power to various electric and electronic devices mounted on the vehicle as well as power to the engine start cell motor. After the engine is started, the battery is charged by the alternator. Here, the output voltage and output current of the alternator are set so that charging and discharging are balanced and the SOC of the battery is maintained at approximately 100%.

  Such a lead-acid battery for starting is almost always installed in the engine room. Therefore, the operating temperature of the lead storage battery is frequently 40 ° C. or higher, and further, the lead storage battery is frequently used at a high temperature of 80 ° C., and the lead storage battery is used with an overcharge tendency.

  When the lead storage battery is overcharged, the water in the electrolytic solution is decomposed into oxygen gas and hydrogen gas and discharged outside the battery, so that the water in the electrolytic solution is reduced. As a result, the concentration of dilute sulfuric acid in the electrolytic solution increases, and the capacity decreases due to corrosion deterioration of the positive electrode plate. In addition, when the electrolytic solution surface is lowered and the electrode plate is exposed from the electrolytic solution, problems such as a rapid decrease in discharge capacity and corrosion of the connecting portion between the negative electrode plate and the strap occur.

  As described above, particularly in a lead-acid storage battery for start-up, suppression of moisture reduction (hereinafter referred to as “liquid reduction”) in the electrolyte is a serious problem. For the purpose of suppressing liquid reduction of this lead storage battery, a battery using a Pb—Ca-based alloy has been put into practical use for both the positive grid and the negative grid.

  On the other hand, the cause of the liquid reduction of the lead storage battery is due to water electrolysis as described above, water vapor generated by evaporation of a part of the water in the electrolyte, and the electrolyte in a mist form, Some are generated by being discharged out of the battery. In the lead storage battery for start-up, the electrolyte surface vigorously shakes due to vibration while the vehicle is running, so that electrolyte mist is likely to be generated inside the cell chamber. Further, when the gas generated during charging is detached from the electrolyte surface, mist of the electrolyte is generated.

  In order to suppress such reduction of the electrolyte solution due to evaporation of moisture in the electrolyte solution or dissipation of the electrolyte solution mist to the outside of the battery, for example, Patent Document 1 discloses a liquid port plug attached to the liquid port. The structure which affixes the sheet | seat to cover with an adhesive with a lid | cover and covers the exhaust hole for gas exhaustion provided in the liquid stopper with a sheet | seat is shown.

  If there is no such sheet and the exhaust hole is exposed to the outside of the battery, the internal pressure of the exhaust hole becomes negative due to the difference in water vapor partial pressure inside and outside the battery or the air flow outside the battery. Is discharged out of the battery.

On the other hand, the structure shown in Patent Document 1 forms a narrow gap between the exhaust hole and the outside air of the battery between the sheet and the lid, so that the water vapor and the electrolyte mist in the battery can be easily removed. The battery does not dissipate through the gap. Further, since the exhaust hole is not directly exposed to the air flow outside the battery, the discharge of water vapor or electrolyte mist to the outside of the battery due to the air flow is suppressed.
JP-A-2005-276741

  The configuration of attaching a sheet to a lid as shown in Patent Document 1 is very simple because it can be realized by additionally attaching a sheet to an existing battery. The effect is also high.

  On the other hand, generation of oxygen / hydrogen gas cannot be completely prevented in a liquid lead-acid battery, and oxygen / hydrogen gas is always generated when the lead-acid battery is left or charged.

  When the lead storage battery as described above is continuously used with an overcharge tendency, the generation of oxygen / hydrogen gas causes a pressure difference between the inside and outside of the battery, and the gas inside the battery is discharged outside the battery. At the same time, the water vapor and electrolyte mist in the battery are also discharged at the same time as this gas is discharged. There was a phenomenon that a small amount of electrolyte or water oozes out.

  In addition, the exuded electrolyte and water spread through the gap between the lid and the sheet due to capillary action, and the two lids and the sheet finally pass through these electrolyte and water, and the electrolyte and water are discharged from the battery. Since it leaked outside or the lid and the sheet were in close contact with each other, sticking occurred between them, and there was a case where discharge of gas out of the battery was hindered. When the discharge of gas was hindered, the battery internal pressure increased, and the battery case and the cell interval wall provided in the battery case were sometimes deformed. Such deformation of the cell spacing walls compresses the adjacent cell chambers and reduces the internal volume thereof, so that the electrolyte level rises in the adjacent cell chambers, and the electrolyte may leak out of the battery. It was.

  In the liquid lead-acid battery having a configuration in which the liquid spigot is covered with a sheet as described above, there is a slight amount of water or electrolyte solution between the lid and the sheet, and these are in close contact with each other. Even when attached in a state, the gas inside the battery is released to the outside of the battery, thereby suppressing the increase in the battery internal pressure and the deformation of the battery case.

  In order to solve the above-described problem, the invention according to claim 1 of the present invention includes a positive electrode lattice body and a negative electrode lattice body made of a Pb—Ca alloy, and the positive electrode plate and the negative electrode plate are arranged via a separator. The electrode plate group in which the electrode plate ears of the same polarity are respectively welded together by the positive electrode strap and the negative electrode strap is a lead storage battery immersed in the electrolyte, and is joined to the opening of the battery case that houses the electrode plate group Provided with a liquid spout attached to a liquid spout provided on the lid, the liquid spout is provided with an exhaust hole for discharging gas in the battery to the outside of the battery, so as to cover the exhaust hole, A sheet bonded to the lid by an adhesive or an adhesive, and a non-joining portion not having the adhesive or the adhesive is provided on a bonding surface of the sheet and the lid; In, the gap between the lid and the sheet The non-joint portion is provided so that the exhaust gas from the exhaust hole is exhausted to the outside of the battery at a position spaced from the exhaust hole, and the exhaust gas from the exhaust hole is allowed to pass through the sheet to be outside the battery. A lead storage battery in which a slit is formed at a position corresponding to or close to the exhaust hole of the sheet so as to be discharged.

  Furthermore, the invention according to claim 2 of the present invention is characterized in that, in the lead storage battery having the configuration of claim 1, at least two of the slits are arranged so as not to cross each other and to be close to each other. It is.

  According to a third aspect of the present invention, there is provided a lead-acid battery having the configuration of the first or second aspect, wherein lead or lead alloy containing no antimony is used as the positive strap and the negative strap. A storage battery is shown.

  According to the configuration of the present invention described above, in the lead storage battery in which the sheet covering the exhaust hole of the liquid spigot is bonded to the lid for the purpose of further improving the liquid reduction characteristic, the electrolyte solution is provided on the surfaces of the sheet and the lid facing each other. Alternatively, even when water oozes out and these both adhere to each other, the gas in the battery is released to the outside of the battery, and thereby, the rise in the battery internal pressure and the deformation of the battery case due to this are remarkably suppressed, A highly reliable lead-acid battery can be provided.

  Hereinafter, the structure of the lead acid battery by embodiment of this invention is demonstrated. As shown in FIG. 1, a lead storage battery 1 according to an embodiment of the present invention includes a positive electrode plate 2 having a Pb—Ca alloy positive electrode lattice body, a negative electrode plate 3 having a Pb—Ca alloy negative electrode lattice body, and a separator 4. , And an electrode plate group 8 composed of a positive electrode strap 9 and a negative electrode strap 10 that collectively weld electrode plates of the same polarity together with an electrolytic solution 5 that immerses the entire electrode plate surface of the positive electrode plate 2 and the negative electrode plate 3. It is stored in the cell chamber 6 a of the tank 6, and a lid 7 is joined to the upper part of the battery case 6. The positive electrode strap 9 and the negative electrode strap 10 are also immersed in the electrolytic solution 5.

  The lid 7 is provided with a liquid port 7a corresponding to the cell 8, and a liquid port plug 21 is attached to the liquid port 7a. An exhaust hole 22 is provided in the head of the liquid spout 21. In addition, in order to suppress that the electrolyte solution 5 swayed by vibration directly contacts the exhaust hole 22, a splash-proof body 21 a may be provided in the liquid spout 21. Further, an explosion-proof filter 21b as conventionally known may be provided between the splash-proof body 21a and the exhaust hole 22.

  And the sheet | seat 23 which covers the upper part of this exhaust hole 22 is bonded by the lid | cover 7 with the adhesive 24. FIG. Note that the sheet 23 is not bonded to the lid 7 with the adhesive 24 over the entire surface, but is provided with a non-joining portion 23 a where the adhesive 24 does not exist at least at a portion corresponding to the exhaust hole 22.

  The non-joining portion 23a functions as a gas discharge path when the oxygen / hydrogen gas discharged from the exhaust hole 22 is discharged outside the battery. Therefore, as shown in FIG. 2, for example, a non-joining portion 23a is provided up to the end of the sheet 23 so that gas is discharged from all the exhaust holes 22 to the outside of the battery. Gas is exhausted to the atmosphere. In FIG. 2, on the bonding surface of the sheet 23 and the lid 7, a portion excluding the non-joined portion 23 a, that is, a portion bonded with the adhesive 24 is shown as a hatched portion A.

  By disposing the sheet 23 so as to face the exhaust hole 22, the exhaust hole 22 is not exposed to the air flow around the battery, so that the water vapor or the electrolyte mist inside the battery is exhausted by the air flow around the battery as described above. Since the phenomenon sucked out from the hole 22 is suppressed, liquid reduction due to evaporation of water in the electrolytic solution or dissipation of the electrolytic solution mist to the outside of the battery is suppressed.

  Further, the gas exhaust path extending from the exhaust hole 22 to the outside of the battery exists as a narrow space (about 0.5 mm or less as a gap dimension in the height direction) between the lid 7 and the sheet 23, or Since the sheet 23 is in contact with the sheet 23, the gas, water vapor, and electrolyte mist in the battery are hardly discharged out of the battery unless the battery internal pressure increases beyond the atmospheric pressure. As a result, the decrease of the electrolyte is remarkably suppressed. As the sheet 23, a sheet having a thickness of about 0.05 to 0.5 mm, such as a polypropylene resin having acid resistance, may be used.

  In the lead storage battery 1 of the present invention, a slit 23 c is further arranged at a position adjacent to the exhaust hole 22 of the sheet 23. Although the slit 23c is normally closed, as shown in FIG. 3, when the sheet 23 is pushed up around the exhaust hole 22 due to an increase in the internal pressure of the battery, the slit 23c opens and stays in the battery. Since the gas is released outside the battery through the slit 23c, an increase in the battery internal pressure is suppressed.

  In the present invention, the slit 23 c is opened by the upward deformation of the sheet 23 around the exhaust hole 22. Therefore, the slit 23c is provided at a position where the sheet 23 is deformed upward due to an increase in the battery internal pressure.

  The slit 23c is preferably provided at least for each exhaust hole 22. Further, as the slit 23c, one slit 23c can be provided for each exhaust hole 22 as shown in FIG. 2, but a plurality of slits are provided for each exhaust hole 22 as shown in FIG. 23d can also be provided. Normally, one or two exhaust holes 22 are provided in the liquid spout 21, but the position of the exhaust holes 22 varies somewhat depending on the tightening degree of the liquid spout 21. Depending on this variation, the distance between the exhaust hole 22 and the slit 23c may be increased.

  In such a case, even when the battery internal pressure increases, the slit 23c hardly deforms above the sheet 23, and the slit 23c is difficult to open. Therefore, in consideration of the variation in the position of the exhaust hole 22, if a plurality of slits 23 d are provided corresponding to the liquid stopper 21, the slit is always located in the vicinity of the exhaust hole 22 even if the position of the exhaust hole 22 varies. 23d is present, and the slit 23d adjacent to the exhaust hole 22 is opened, thereby suppressing an increase in the battery internal pressure and the deformation of the battery case.

  Although FIG. 4 shows an example in which a plurality of slits 23d are provided in parallel to each other, it is preferable that at least the slits 23d are arranged so as not to cross each other. When the slit 23d intersects, the slit 23d is always turned up starting from the intersecting vertex, and as a result, the slit 23d is always open. And since the gas, water vapor | steam, or electrolyte solution mist from the exhaust hole 22 is always discharged | emitted from the slit 23d opened, the liquid reduction suppression effect by the sheet | seat 23 is impaired. Therefore, in order to stably suppress an increase in the internal pressure of the battery, when providing a plurality of slits 23d in the sheet 23 corresponding to the exhaust holes 22, it is preferable to arrange the slits 23d so that the slits 23d do not intersect each other. .

  As a more preferable embodiment of the present invention, a lead alloy containing no antimony is used for the positive strap 9 for connecting the positive plates 2 and the negative strap 10 for connecting the negative plates 3. When antimony is contained in the negative electrode strap 10, the hydrogen overvoltage of the negative electrode strap 10 is reduced, and the generation of hydrogen gas on the negative electrode strap 10 is promoted. Further, when antimony is contained in the positive electrode strap 9, the antimony eluted in the electrolytic solution 5 is deposited on the negative electrode plate 3 along with the oxidation of the positive electrode strap 9, thereby reducing the hydrogen overvoltage of the negative electrode plate 3. The amount of hydrogen gas generated above increases.

  Moreover, the negative electrode potential at the time of charging shifts more preciously due to the decrease in hydrogen overvoltage at the negative electrode plate 3 and the negative electrode strap 10. When a lead-acid battery is charged at a constant voltage, such as for ordinary automobiles and backups, the negative electrode potential at the time of charging shifts to noble, so the positive electrode potential shifts to noble, so oxygen gas on the positive electrode plate 2 Occurrence is promoted. At the same time, elution of antimony at the positive electrode strap 9 is further promoted, and hydrogen gas generation at the negative electrode plate 3 further proceeds.

  Therefore, when a lead alloy containing antimony is used for the positive electrode strap 9 and the negative electrode strap 10, oxygen / hydrogen gas bubbles generated inside the battery rise in the electrolyte solution, and when these bubbles leave the electrolyte solution, Electrolytic droplets (electrolyte mist) are generated. These electrolyte mists are partially discharged at the same time as the oxygen / hydrogen gas is discharged from the exhaust hole 22, collide with the surface of the sheet 23, and are again condensed as electrolytic droplets.

  In a preferred embodiment of the present invention, the use of lead or lead alloy containing no antimony for the positive electrode strap 9 and the negative electrode strap 10 suppresses generation of oxygen / hydrogen gas that causes condensation of the electrolyte mist. Further, the exudation of electrolytic droplets between the sheet 23 and the lid 7 and the sticking between the sheet 23 and the lid 7 due to this are suppressed. Therefore, an increase in the internal pressure of the battery due to gas retention inside the battery and a deformation of the battery case due to this are suppressed.

  In addition, it is preferable to use lead or a lead alloy containing no antimony for the pole column 12 and the connection body 13 connected to the positive electrode strap 9 and the negative electrode strap 10.

  As the lead alloy not containing antimony, for example, a lead-tin alloy or a lead-calcium alloy can be used. In the present invention, when the amount of antimony contained in the lead or lead alloy as an inevitable impurity and does not increase the amount of gas generated inside the lead storage battery (for example, 50 ppm or less) is substantially contained in the present invention. It can be regarded as lead or lead alloy not included.

  In order to suppress vibration overflow when the lead storage battery 1 vibrates and ignition due to drawing of external sparks into the battery, as shown in FIG. An explosion-proof filter 21b can be arranged.

(Example 1)
Hereinafter, the effects of the present invention will be described with reference to examples. A lead storage battery (80D26 type start lead storage battery in JIS D5301) according to the present invention example and a comparative example was manufactured, and the amount of liquid reduction when the battery was overcharged while applying vibration to each lead storage battery was evaluated. Moreover, about each battery after completion | finish of overcharge, the liquid bleeding state from an exhaust hole was confirmed. Furthermore, the presence or absence of sticking of the sheet and the lid and the influence of the sticking on the battery internal pressure and the battery case deformation when the lead storage battery was left in a state where such liquid bleeding occurred were evaluated.

(Battery A of the present invention example)
The battery A of the present invention example is a lead storage battery according to the above-described embodiment of the present invention. The positive plate is an expanded lattice using lead-0.07 wt% calcium-1.6 wt% tin alloy, and the negative plate is an expanded lattice using lead-0.07 wt% calcium-0.3 wt% tin alloy. Using.

  As the separator, a microporous film in which silica and mineral oil were added to polyethylene resin was used, and this was made into a bag shape to enclose the positive electrode plate.

  As the positive electrode strap and the negative electrode strap, a lead-2.5 wt% tin alloy having an antimony content limited to less than 0.001 wt% was used. Further, for the pole column and the connection body, lead-2.5 wt% antimony-0.2 wt% arsenic alloy was used.

  The sheet has a width of 40 mm × a length of 260 mm of a polypropylene resin film having a thickness of 0.2 mm. As shown in FIG. 2, a strip-shaped portion having a width of 20 mm is set as a non-joining portion at the center in the width direction. The sheet 22 was bonded to the lid 7 using an acrylic emulsion-based pressure-sensitive adhesive at other portions (shaded portion A in FIG. 2). In addition, the sheet | seat 23 was bonded together to the lid | cover 7 so that the non-joining part 23a may correspond to the liquid stopper 21 arrange | positioned in a line. Therefore, the exhaust gas from the exhaust hole 22 is exhausted from both ends of the sheet 23 through the gap between the lid 7 and the sheet 23 corresponding to the non-joining portion 23a.

  Further, in the battery A of the present invention example, as shown in FIG. 2, a 7 mm slit 23 c was provided at a position adjacent to the exhaust hole 22. In addition, the slit 23c provided in each exhaust hole 22 is provided on the virtual straight line. In addition, as shown in FIG. 1, the liquid spigot 21 is provided with a splash-proof body 21a and an explosion-proof filter 21b.

(Battery B of the present invention example)
The battery B of the present invention example uses the lead-2.5 wt% antimony-0.2 wt% arsenic alloy as the lead alloy for the positive and negative straps in the battery A of the present invention example.

(Battery C of the present invention example)
In the battery C of the present invention example, in the battery A of the present invention example, two slits 23d as shown in FIG. Each of the slits 23d has a length of 7.0 mm and is arranged at an interval of 2.5 mm, and two pairs of these slit pairs are arranged in a point-symmetrical position with respect to the center of the liquid stopper 21.

(Battery D of the present invention example)
In the battery D of the present invention example, the slit formed in the sheet 23 in the battery B of the present invention example was the slit 23d similar to the battery C of the present invention example.

(Battery E of Comparative Example)
The battery E of the comparative example is a battery in which the slit 23c in the battery A of the present invention example is removed and no slit is provided in the sheet 23. The battery A is the same as the battery A of the present invention except that no slit is provided.

(Comparative battery F)
The battery F of the comparative example uses the lead-2.5 wt% antimony-0.2 wt% arsenic alloy as the lead alloy for the positive strap and the negative strap in the battery E of the comparative example.

(Battery G of comparative example)
The battery G of the comparative example is a battery in which the sheet 23 of the battery A of the present invention example is removed. Others are the same as the battery A of the present invention.

(Battery H of comparative example)
The battery H of the comparative example is a battery in which the sheet 23 of the battery B of the present invention example is removed, and the rest is the same as the battery B of the present invention example.

  Table 1 shows a list of the configurations of the batteries described above.

  While charging each battery of the present invention example and the comparative example in a temperature atmosphere of 60 ° C. at a charging voltage of 14.5 V (maximum charging current 25 A) for 2000 hours, the battery is vertically moved at an acceleration of 1 G (30 Hz). The weight loss of the battery when vibration was applied was measured as the amount of liquid reduction. In addition, the appearance and leakage of water and electrolyte around the exhaust hole of the liquid stopper were confirmed by visual appearance inspection.

  Table 2 shows the results of the measurement of the battery weight loss and the visual appearance results. In addition, the amount of liquid reduction was shown by the percentage when the amount of liquid reduction of the battery H of the comparative example was 100%.

  From the results shown in Table 2, the amount of liquid reduction is significantly suppressed in the batteries A to F in which the sheet covering the exhaust hole of the liquid spigot is bonded to the lid as compared with the batteries G and H that do not use the sheet. Yes. When the sheet is attached to the lid, water / electrolyte oozes out in the gap between the sheet and the lid, but minute droplets are attached to the sheet side and leak out of the battery. It was not like this.

  After completion of charging, these batteries were left in a constant temperature bath (humidity 0 RH%) at 60 ° C. for 168 hours. Thereafter, the maximum value of the battery internal pressure and the deformation state of the battery case when each battery was charged with a constant current of 4.8 A were confirmed. In this test, gas is deliberately generated inside the battery by charging, and the sticking state of the sheet and the lid is evaluated by the increase in the battery internal pressure at that time. When the internal pressure of the battery rises with the generation of gas, it can be seen that the sheet and the lid are in close contact with each other and the gas inside the battery cannot be discharged outside the battery. On the other hand, when the battery internal pressure rise does not rise to a level that would cause battery case deformation, a path for the gas inside the battery to be discharged to the outside of the battery is secured between the seat and the lid. I can confirm.

  In this example, the internal pressure of the battery during constant current charging of 4.8 A was continuously measured, and the behavior was observed. When the battery internal pressure reached 20 kPa, that is, reached a level where significant battery case deformation occurred, charging was stopped. Table 3 shows the behavior of the battery internal pressure of each battery.

  As shown in Table 2, with respect to the battery E and the battery F in which the sheet was not provided with a slit, when the battery E and the battery F were charged after being left standing, an abnormal increase in battery internal pressure and significant battery case deformation were observed. In each of these batteries, the periphery of the exhaust hole is in close contact with the sheet, and gas discharge from the exhaust hole is hindered. This is because the sheet and the lid are brought into close contact with each other by the droplets containing the electrolyte attached to the sheet surface by continuous charging for 2000 hours, and the sheet and the lid are almost fixed by being left at a high temperature. It was.

  On the other hand, the battery G and the battery H that do not use a sheet naturally have no significant increase in internal pressure. However, the internal pressure of the battery increased by 1.0 kPa and 1.2 kPa, respectively, from the atmospheric pressure due to the ventilation resistance of the explosion-proof filter provided in the liquid stopper. This internal pressure does not lead to battery case deformation.

  Regarding the batteries A to D according to the present invention, although the sheet was used, the internal pressure value was not significantly increased, and the battery case deformation was also suppressed. In particular, for the batteries C and D in which a plurality of slits 23d are formed in parallel, the internal pressure rises at the same level as the batteries G and F without using a sheet. It can be considered that by providing a plurality of slits, even if the positions of the exhaust holes vary somewhat, the slits are always arranged at positions close to the exhaust holes, so that gas can be discharged stably from the slits. Therefore, the battery C and the battery D provided with a plurality of slits are more preferable than the battery A and the battery B.

  In the battery of the present invention, since the slit provided close to the exhaust hole has the function of opening the slit and discharging the gas inside the battery only when the internal pressure of the battery rises, the sheet and the lid Even when a slight amount of electrolyte is adhered between the two, the gas generated inside the battery is discharged from the slit, so that an abnormal increase in the internal pressure of the battery and the deformation of the battery case due to this are suppressed. .

  Regarding the lead alloy for straps, both the positive electrode and the negative electrode do not contain antimony, the battery A and the battery C using the lead-tin alloy are compared with the battery B and the battery D using the lead-antimony alloy, The increase in the internal pressure of the battery is also suppressed, the gas is smoothly discharged from the exhaust hole, and the liquid reduction is further suppressed, which is most preferable.

  From the above, according to the present invention, the sheet covering the exhaust hole is bonded to the lid, thereby improving the liquid reduction characteristics of the lead storage battery and the exhaust hole generated when the sheet and the cover are bonded together. It was confirmed that the exhaust hole was closed due to the close contact between the sheet and the lid in the vicinity, the abnormal increase in battery internal pressure caused by this, and the battery case deformation could be suppressed.

  The present invention suppresses liquid reduction in a lead storage battery extremely remarkably, suppresses clogging of exhaust holes, does not cause an abnormal increase in internal pressure during charging, and does not cause battery case deformation. It is suitable for liquid lead acid batteries for various uses including lead acid batteries for starting.

Sectional drawing which shows the lead acid battery of this invention The figure which shows the lead acid battery of this invention The figure which shows the state where the slit opened The figure which shows the lead acid battery of this invention

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Lead acid battery 2 Positive electrode plate 3 Negative electrode plate 4 Separator 5 Electrolyte 6 Battery case 6a Cell chamber 7 Lid 7a Liquid port 8 Electrode plate group 9 Positive electrode strap 10 Negative electrode strap 11 Terminal 12 Polar column 13 Connector 21 Liquid port plug 21a Splash Body 21b Filter 22 Exhaust hole 23 Sheet 23a Non-joining part 23c Slit 23d Slit 24 Adhesive

Claims (3)

It has a positive electrode lattice body and a negative electrode lattice body made of a Pb-Ca alloy, the positive electrode plate and the negative electrode plate are arranged via a separator, and the electrode plate ears of the same polarity are collectively welded by the positive electrode strap and the negative electrode strap, respectively. A lead storage battery in which the electrode plate group is immersed in an electrolytic solution, and includes a liquid port plug attached to a liquid port provided on a lid joined to an opening of a battery case that houses the electrode plate group. The plug is provided with an exhaust hole for discharging the gas in the battery to the outside of the battery, and includes a sheet bonded to the lid by an adhesive or an adhesive so as to cover the exhaust hole, And the bonding surface of the lid is provided with a non-joining portion that does not have the adhesive or the adhesive, and in the non-joining portion, exhaust gas from the exhaust hole through the gap between the lid and the sheet, Position away from the exhaust hole A slit is provided at a position corresponding to or close to the exhaust hole of the sheet so as to exhaust the exhaust gas from the exhaust hole through the sheet and exhaust it out of the battery. Formed lead acid battery. The lead acid battery according to claim 1, wherein at least two of the slits are arranged so as not to cross each other and to be close to each other. The lead acid battery according to claim 1 or 2, wherein lead or a lead alloy containing no antimony is used as the positive electrode strap and the negative electrode strap.

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