JP2010267507A - Lead-acid battery - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To restrain changes of an electrolyte solution face generating deformation of inter-cell barrier ribs caused by a sheet sticking to a drainage port or a decompressed state inside a battery and failures such as liquid leak, corrosion of an anode strap, and deterioration of battery capacity, in a lead-acid battery having a structure of covering the drainage port with the sheet with a view to restrain liquid volume decrease. <P>SOLUTION: A material with flexibility is use as the sheet, crossing slits with a plurality of slits crossed or bent slits having bent parts are provided at a part corresponding to a top face of a liquid plug forming the drainage port of the sheet, and at the same time, a gap part for allowing deflection deformation of pieces formed in the slits in a direction of the liquid plug top face is formed between the top face of the liquid plug and the sheet. <P>COPYRIGHT: (C)2011,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 such as 80 ° C.

  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 lead-calcium 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 due to 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 a decrease in the electrolyte due to the evaporating moisture or electrolyte mist in the electrolyte being dissipated out of the battery, a sheet covering the liquid stopper is attached to the lid with an adhesive, The structure which covers the exhaust hole for the gas exhaust provided in the stopper with a sheet | seat is shown.

  Thus, since the structure which affixes a sheet | seat on a lid | cover can be implement | achieved by adhering a sheet | seat additionally to the existing battery, it is very simple and the effect of liquid reduction suppression 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 order to solve these problems, in Patent Document 1, a sheet covering a liquid spigot attached to a liquid spout is attached to a lid with an adhesive, and an exhaust hole for gas exhaust provided in the liquid spigot is provided in the sheet. It is proposed that the sheet covering the exhaust hole and forming a non-intersecting slit at a position corresponding to or close to the exhaust hole.

  In the liquid lead-acid battery having a structure in which the liquid spigot is covered with a sheet by the structure shown in Patent Document 1, there is a slight amount of water or electrolyte solution between the lid and the sheet, and these are in close contact Even in the case where the battery is stuck, the gas inside the battery is released to the outside of the battery through the slits that do not intersect, thereby suppressing the rise of the battery internal pressure and the deformation of the battery case due to this. It has become possible.

JP 2008-71692 A

  However, the inventors of the present invention, in the lead storage battery having the structure shown in Patent Document 1, when there is a small amount of dew condensation water between the lid and the sheet, or a liquid such as a small amount of leached electrolyte, The lid and the sheet may stick through this liquid, and from such a state, when the battery temperature decreases or the oxygen gas present inside the cell is absorbed by the negative electrode, the internal pressure of the cell chamber is It was found that the pressure was reduced to a pressure lower than atmospheric pressure. Once in a reduced pressure state, the battery is charged to generate gas in the cell chamber or until the operation such as heating the battery to increase the internal pressure of the battery beyond the atmospheric pressure is performed. Has not been opened, and it has been found that a reduced pressure state is maintained.

  In FIG. 3 of Patent Document 1, it is shown whether the adhesive has a certain thickness and there is a gap between the sheet and the top surface of the liquid stopper. In preparation, the thickness of the pressure-sensitive adhesive is about 5 μm to 50 μm, and the space between the actual sheet and the top surface of the liquid spigot is extremely narrow, and sticking between the sheet and the liquid spout occurs. In addition, if the adhesive is applied thick enough to prevent sticking between the sheet and the liquid plug, the sheet will rise significantly from the lid, and the stay when fixing the lead-acid battery to equipment such as a vehicle There is also a problem that the sheet interferes with the sheet, and the sheet breaks due to vibration and rubbing due to this, and by increasing the thickness of the adhesive, it is extremely difficult to prevent the sheet from sticking to the top surface of the liquid stopper It was difficult and not realistic.

  And, in the lead storage battery in which the inside of the battery case is partitioned into a plurality of cell chambers by partition walls, as described above, when the cell chambers are in a reduced pressure state, the internal pressure is hardly uniform between the cell chambers. The internal pressure difference between the two is almost unavoidable. Due to such an internal pressure difference, the partition walls defining the cell chamber are deformed toward the cell chamber having a lower internal pressure, and therefore the volume of the cell chamber is changed. That is, the cell volume with the lower internal pressure becomes smaller, and the volume of the cell chamber with the higher internal pressure becomes larger. As a result, the electrolyte surface is lower than the initial position in the cell chamber having a higher internal pressure, and the electrolyte surface is higher than the initial position in the cell chamber having a lower internal pressure.

  Due to such a change in the electrolyte surface, when the electrolyte surface height exceeds a predetermined range, the leakage resistance performance of the battery, in particular, the leakage resistance performance when the battery is vibrated, sharply decreases, Also, if the height of the electrolyte surface is below a predetermined range, the strap corrodes due to exposure from the electrolyte surface, and further, the battery capacity decreases due to the electrode plate surface being exposed from the electrolyte solution. Give rise to

  In addition, as described above, the deformation of the partition wall and the fluctuation of the electrolyte surface due to the internal pressure difference are not temporary, but are fixed. For example, it corresponds to the case where this lead storage battery is stored for a long period of time after chemical conversion charging of the lead storage battery. That is, after the temperature of the battery rises due to chemical charging, the volume of the gas in the cell chamber shrinks because the sheet does not open when the sheet sticks to the top of the liquid stopper due to the battery temperature drop during storage. As a result, the internal pressure of the cell becomes a reduced pressure state lower than the atmospheric pressure. As a result, the inevitably generated internal pressure difference between the cell chambers is maintained during battery storage.

  If the storage period of the battery in such a state is relatively short, the battery is charged when the use of the battery is started. Therefore, the internal pressure of the cell chamber is reduced by the oxygen gas and hydrogen gas generated in the cell. As a result, the adhesion between the lid and the sheet is peeled off by the internal pressure, and the slit is opened, whereby the internal pressure of the cell chamber is restored to the atmospheric pressure, and the deformation of the partition walls is also restored.

  On the other hand, it has been found that when the storage period of the battery is long (for example, 3 months), the deformation of the partition wall is fixed, and even when the internal pressure of the battery is restored to the atmospheric pressure, the deformation of the partition wall is not restored.

  The present invention, as described above, in a liquid lead-acid battery having a configuration in which the liquid spigot is covered with a sheet, the lid and the sheet are separated by a minute amount of condensed water or electrolyte existing between the lid and the sheet. Even in the case of sticking in close contact with each other, it is possible to suppress the internal pressure difference between the cell chambers by suppressing the cell chamber from being in a reduced pressure state, and to deform the partition wall caused by such an internal pressure difference, or the electrolytic solution The object is to suppress surface fluctuations and defects caused thereby (leakage, strap corrosion caused by exposure from the electrolyte, and capacity reduction due to oxidative degradation of the negative electrode plate).

  In order to solve the above-described problem, in the invention according to claim 1 of the present invention, the positive electrode plate and the negative electrode plate are arranged via the separator, and the electrode plate ears of the same polarity are assembled by the positive electrode strap and the negative electrode strap, respectively. A welded electrode plate group, a battery case in which a plurality of cell chambers containing the electrode plate group and the electrolytic solution are partitioned by partition walls, a lid joined to the opening of the battery case, and the cell chamber Correspondingly, a lead-acid battery having a liquid port plug provided with an exhaust hole for exhausting the gas in the battery case to the outside of the battery while being attached to the liquid port provided in the lid, A sheet bonded to the lid by a bonding agent such as an adhesive or an adhesive is provided so as to cover the exhaust hole, the sheet has flexibility, and the bonding surface of the sheet and the lid is bonded to the bonding surface. A non-joining portion having no agent, wherein the non-joining portion is the lid The exhaust gas from the exhaust hole is formed so as to be discharged out of the battery at a position spaced from the exhaust hole through a gap with the sheet, and a plurality of slits are provided at a position facing the liquid plug of the sheet. A crossing slit formed by crossing each other and a portion of the top surface of the liquid spigot facing the piece formed by the crossing slit is depressed more than the bonding surface of the lid with the sheet Thus, a lead storage battery is provided, wherein a gap is provided between the top surface and the sheet, and the exhaust hole is provided at a position corresponding to the gap.

  Further, the invention according to claim 2 of the present invention is that, in the invention according to claim 1 of the present invention, the positive electrode plate and the negative electrode plate are arranged via the separator, and the electrode plate ears of the same polarity are respectively connected to the positive electrode strap and An electrode plate group formed by collective welding with a negative electrode strap, a battery case in which a plurality of cell chambers containing the electrode plate group and the electrolyte solution are partitioned by partition walls, a lid joined to the opening of the battery case, A lead storage battery having a liquid port plug provided with an exhaust hole for discharging the gas in the battery case to the outside of the battery while being attached to a liquid port provided in the lid corresponding to the cell chamber The sheet includes a sheet bonded to the lid by a bonding agent such as an adhesive or an adhesive so as to cover the exhaust hole, the sheet having flexibility, and a bonding surface of the sheet and the lid A non-joining portion that does not have the bonding agent, The exhaust gas from the exhaust hole is formed to be discharged out of the battery at a position spaced from the exhaust hole through the gap between the recording lid and the sheet, and bent to a position facing the liquid plug of the sheet. Forming the bent slit, and the portion of the top surface of the liquid stopper facing the piece formed by the bent slit is depressed more than the bonding surface of the lid with the sheet, The lead storage battery is characterized in that a gap is provided between a top surface and the sheet, and the exhaust hole is provided at a position corresponding to the gap.

  According to a third aspect of the present invention, in the lead storage battery of the first or second aspect, lead or a lead alloy containing no antimony is used as the positive strap and the negative strap.

  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 reducing liquid properties, the cell chamber is in a reduced pressure state, and the internal pressure between the cells is As a result, the deformation of the partition walls between the cells is remarkably suppressed, and the variation of the electrolyte solution surface and the variation of the electrolyte solution surface can be suppressed. In addition, there is a remarkable effect that it is possible to provide a highly reliable lead storage battery that suppresses problems such as corrosion of the negative electrode strap or reduction in battery capacity caused by fluctuations in the electrolyte surface.

The figure which shows the lead acid battery by the 1st Embodiment of this invention. The figure which shows the cross section of the lead acid battery by 1st Embodiment of this invention. (A) The figure which shows the other lead acid battery by 1st Embodiment of this invention (b) The figure which shows the other lead acid battery by 1st Embodiment of this invention The figure which shows the principal part cross section of the lead acid battery by 1st Embodiment of this invention. The figure which shows the principal part cross section of the other lead acid battery by 1st Embodiment of this invention. The figure which shows the principal part cross section of the other lead acid battery by 1st Embodiment of this invention. The figure which shows the lead acid battery by the 2nd Embodiment of this invention. The figure which shows the lead acid battery of the comparative example

(First embodiment of the present invention)
Hereinafter, the configuration of the lead-acid battery according to the first embodiment of the present invention will be described. FIG. 1 is a diagram showing a top surface of a lead storage battery 1 according to an embodiment of the present invention, and FIG. 2 is a diagram showing a BB ′ cross section of the lead storage battery 1 in FIG. FIG. 4 is an enlarged view of a part of FIG.

  As shown in FIG. 2, an electrode plate group 8 including a positive electrode plate 2, a negative electrode plate 3 having a negative electrode grid and a separator 4, and a positive electrode strap 9 and a negative electrode strap 10 for collectively welding the same polarity electrode plates, respectively. In the initial state in which the use of the lead storage battery 1 is started, an electrolyte 5 is provided that immerses at least the entire surface of the positive electrode plate 2 and the negative electrode plate 3. As is well known, there is a possibility that the electrolytic solution surface is lowered and the electrode plate surface is exposed due to the liquid reduction, and the same applies to the lead storage battery 1 of the present invention. However, at least the lead storage battery 1 of the present invention and the lead storage battery 1 ′ of the present invention, which will be described later, are immersed in the electrolytic solution 5 at the initial state when the use is started. The electrode plate group 8 and the electrolytic solution 5 are accommodated in a cell chamber 6 a of the battery case 6, and a lid 7 is joined to the upper part of the battery case 6. In addition, it is preferable that the positive electrode strap 9 and the negative electrode strap 10 are also immersed in the electrolytic solution 5 in order to suppress corrosion and heat generation in these straps. In the example shown in FIG. 2, a pole column 12 is connected to the positive strap 9, connected to a terminal 11 penetrating the lid 7, and a negative electrode group adjacent to the negative strap 10 via a partition wall 6b (FIG. 2). However, it is merely an example, and the connection structure between the electrode plate group 8 and the terminal 11 or the connection structure between the electrode plate groups 8 is other than the above. The known configuration can be applied.

  It is preferable to use a lead-calcium alloy as a base material for both the positive and negative grid bodies. This is because the lead-calcium alloy suppresses the generation of gas during charging as compared with the lead-antimony alloy, and as a result, the acidity generated with the gas generation is also suppressed. Such acid service is discharged from the exhaust hole 22, and sticking between the sheet 23 and the top surface 21 c of the liquid spout 21 described later is likely to occur. In order to suppress such sticking, it is preferable to use a lead-calcium alloy for the lattice of the positive electrode and the negative electrode. However, as for the positive electrode lattice, a lead-antimony alloy thin layer (thickness of about 1 to 30 μm) containing about 1 to 10% by mass of antimony is formed on the surface of the positive electrode lattice. Compared to the above, since it is possible to suppress an increase in gas generation amount of the lead storage battery, it can be handled in the same manner as the positive electrode lattice of the lead-calcium alloy.

  Similarly, the negative electrode strap 10 and the positive electrode strap 9 do not contain antimony such as lead-tin alloy (however, it may contain antimony as an inevitable impurity of about 0.002% by mass). It is preferable.

  The lid 7 is provided with a liquid port 7a corresponding to the cell chamber 6a, 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 prevent the electrolytic solution 5 swayed by vibration from directly contacting 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 together with the lid | cover 7 with the bonding agent. Note that the sheet 23 is not bonded to the lid 7 with the bonding agent on the entire surface, but at least one of the bonding surfaces of the lid 7 and the sheet 23 is released so that the gas discharged from the exhaust hole 22 can be released into the atmosphere. The non-joining part 23a which does not have a joining agent is provided in a part. The joining member may be provided on either the surface of the lid 7 or the surface of the sheet 23, or both. However, the joining member is considered in consideration of workability and productivity in the bonding process of the sheet 23. It is preferable to form the layer in advance on the portion of the sheet 23 excluding the non-joining portion 23a.

  As an example, as shown in FIG. 1, for example, a strip-shaped non-joint portion 23 a sandwiched between the strip-like joints on both sides of the sheet 23 so that gas is discharged from all the exhaust holes 22 to the outside of the battery. The end of the sheet 23 is provided, and the gas is finally discharged to the atmosphere at the end of the sheet 23. In FIG. 1, a portion excluding the non-bonded portion 23 a on the bonding surface of the sheet 23 with the lid 7, that is, a portion bonded and fixed with a bonding agent is shown as a hatched portion A. In addition, it is preferable to form the circumference | surroundings of the liquid port 7a of the lid | cover 7 on substantially the same plane on the relationship which joins the sheet | seat 23 to the lid | cover 7. FIG.

  As the bonding agent, various pressure-sensitive adhesives or adhesives having a bonding force capable of fixing the sheet 23 to the lid 7 can be used. Further, since the sheet 23 is used for the purpose of suppressing liquid reduction, a liquid such as moisture, dilute sulfuric acid, or a material capable of suppressing permeation of water vapor is used, and the sheet 23 has flexibility. Use things.

  For example, a film sheet such as polypropylene or polyethylene, or a PET resin film is used. The coating thickness of the bonding agent is about 10 to 40 μm as in the case of a general label. If the coating thickness of the bonding agent is intentionally increased, the sheet 23 rises from the lid 7 and fixes the lead storage battery 1. This is not preferable because it may interfere with the stay and the like, and the sheet 23 may be torn.

  In the example shown in FIG. 1, an example in which the non-joining portion 23 a is arranged in a single band shape is shown, but the non-joining portion 23 a may be arranged continuously from the exhaust hole 22 to the outside of the lead storage battery 1. As shown in FIG. 3A, the non-joining portion 23′a may be formed independently for each liquid spigot 21. As shown in FIG. It is possible to form a pattern in which “a” is formed and each non-joining portion 23 ″ a exhausts the gas discharged from the three liquid spigots 21 to the atmosphere, and the gas can be discharged from the exhaust hole 22. Any formation pattern may be used.

  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 of being sucked out from the hole 22 is suppressed, liquid reduction due to evaporation of moisture in the electrolytic solution or dissipation of the electrolytic solution mist to the outside of the battery is suppressed.

  In the present invention, as shown in FIG. 1 or FIG. 3, an intersecting slit 25 is provided in which a plurality of slits 25 a intersect at a position facing the liquid spout 21 of the sheet 23. Then, as shown in FIG. 4, at least a portion of the top surface 21 c of the liquid spigot 21 that opposes the piece 25 c formed by intersecting the slits 25 a from the bonding surface 7 b of the lid 7 with the sheet 23. Also, the gap portion 26 is provided between the top surface 21 c and the sheet 23 by being depressed. Further, the exhaust hole 22 of the liquid spout 21 is provided at a position that opens to the gap portion 26.

  With the above-described configuration, the portion corresponding to the non-joining portion 23a of the sheet 23 is in close contact with the surface of the lid 7 and the battery temperature decreases, or an oxygen gas absorption reaction is performed in the cell chamber 6a. When the internal pressure is lower than the atmospheric pressure, the piece 25c formed by the intersecting slits 25a is bent and deformed so as to be sucked in the direction of the gap 26, and the slit 25a is opened by the bending deformation of the pieces 25c. The air is introduced into the cell chamber 6a, and the internal pressure of the cell chamber 6a is restored to atmospheric pressure, so that the internal pressure difference between the cell chambers 6a, which deforms the partition wall 6b, is suppressed.

  As a result, variation in the reduced pressure state of the cell internal pressure as occurs in the lead storage battery disclosed in Patent Document 1 causes an increase / decrease in the electrolyte surface due to deformation of the partition walls, and such electrolysis. There is a remarkable effect that it is possible to suppress problems such as leakage of the electrolyte, corrosion of the strap, or reduction of the battery capacity caused by the rise and fall of the liquid level.

  On the other hand, when the portion corresponding to the non-joint portion 23a of the sheet 23 is in close contact with the surface of the lid 7, the internal temperature of the cell chamber 6a is increased by the oxygen gas / hydrogen gas generated when the battery temperature rises or the battery is charged. However, when the pressurized state is higher than the atmospheric pressure, the piece 25c formed by the intersecting slits 25a is bent and deformed above the lead storage battery 1, and the slits 25a are opened, and the inside of the cell chamber 6a Since the gas is released into the atmosphere, an increase in the internal pressure of the cell chamber 6a can be suppressed.

  In the example shown in FIG. 2 and FIG. 4, a bent piece 21 d is formed between the sheet 23 and the liquid spigot 21 by forming a concave portion 21 d on a part of the top surface 21 c of the liquid spigot 21. Although the example in which the gap portion 26 for accommodating 25c is formed has been shown, as shown in FIG. 5, the depressed portion 21'd may be shaped like a step from the top surface 21c. Further, as shown in FIG. 4 and FIG. 5, instead of providing the recessed portions 21d and 21'd in a part of the top surface 21c, the entire top surface 21c is attached to the lid 7 as shown in FIG. A gap 26 having a depth dimension h may be formed by recessing from the bonding surface 7b with the sheet 23.

  Further, the gap portion 26 has a depth dimension h required to release the internal pressure of the cell chamber 6a by bending and deforming the piece 25c so that the internal pressure of the cell chamber 6a is not excessively reduced. Therefore, it is not always necessary to provide the depressed portions 21d and 21'd in order to form the gap portion 26. For example, as shown in FIG. 5, the top surface 21c of the liquid spout 21 formed in a planar shape is provided. The depth dimension h may be secured by positioning the lid 7 below the bonding surface 7b with the sheet 23.

  The depth dimension h is preferably set larger than the thickness of the sheet 23. This is to make sure that the slit 25a is opened in a state where the piece 25c is stored in the gap portion 26. Therefore, as an example, when the sheet 23 having a thickness of about 0.01 mm to 0.5 mm is used, the depth dimension h is set to exceed 0.01 mm and larger than the thickness of the sheet 23. In order to obtain the effects of the present invention, it is not necessary to set the upper limit of the depth dimension h, but it is 5.0 mm or less due to the structural design limitation of the liquid spout 21.

  Moreover, as the slit 25a, for example, a cross-shaped member that is formed with a length of 2 mm to 10 mm and intersects at right angles at the midpoint thereof can be used. In addition, although the formation of the slit 25a and the crossing pattern, dimensions, and the like illustrated can be modified within a range that does not impair the function of the slit 25a of the present invention, in the first embodiment, at least two of the slits 25a cross each other. Thus, the slit 25a is formed to open at the time of bending deformation. In addition, the dimension of the slit 25a illustrated previously can be a dimension included in the top surface 21c of the liquid spigot 21.

  When the slits do not intersect as in Patent Document 1, the slit is not opened even if the inside of the cell is in a reduced pressure state, so the reduced pressure state is not eliminated and the effect of the present invention cannot be obtained.

  Further, even if the slits 25a are formed so as to intersect with each other, if there is no gap portion 26, the piece 25c cannot be bent and deformed downward, so that the slit is not opened and the reduced pressure state is not eliminated. It is not possible.

  Therefore, in the first embodiment of the present invention, in order to obtain the effect of the present invention, a plurality of slits 25a intersect to form a piece 25c and the piece 25c can be bent and deformed downward. It is necessary to form the portion 26.

(Second embodiment of the present invention)
A lead storage battery 1 ′ according to the second embodiment of the present invention has a bent slit 25 ′ having a bend as shown in FIG. 7 instead of the slit 25 a of the lead storage battery 1 according to the first embodiment of the present invention. The other configuration is the same as the configuration of the lead storage battery 1 according to the first embodiment described above.

  Since the bent slit 25 'does not coincide with the shape obtained by connecting the start point and the end point with a straight line, the portion surrounded by the straight line and the bent slit 25' becomes a piece 25'c, and the gap portion 26 is formed below the piece 25'c. By arranging, the same effects as the piece 25c of the first embodiment are exhibited.

  That is, when the internal pressure of the cell chamber 6a is reduced, the piece 25'c is bent and deformed in the direction of the gap 26, so that the bending slit 25 'is opened, and the pressure reduction of the cell chamber 6a is suppressed. Similar to the lead-acid battery 1 according to the first embodiment, the fluctuation of the electrolyte surface due to the deformation of the partition wall 6b and various problems caused by the fluctuation, such as leakage of the electrolyte, corrosion of the negative strap 10 or There is a remarkable effect that it is possible to suppress problems such as a decrease in battery capacity due to oxidative deterioration of the negative electrode plate 3.

  Further, when the internal pressure of the cell chamber 6a becomes higher than the atmospheric pressure, the piece 25'c is bent and deformed upward in the direction opposite to the gap portion 26, and the bending slit 25 'is opened. The pressurization of 6a is eliminated, and an abnormal increase in battery internal pressure can be suppressed.

  Although the U-shaped pattern is illustrated in FIG. 7 as the formation pattern of the bent slit 25 ', the present invention is not limited to this, and for example, a U-shaped, V-shaped or arc-shaped pattern may be used. Good. As a formation pattern of the bent slit 25 ′, an appropriate shape may be selected in consideration of easiness in slit formation. Further, the dimension of the bent slit 25 ′ is about several mm to several tens of mm long as described in the first embodiment, and is included in the dimension of the top surface 21 c of the liquid spout 21. Can be set to dimensions.

  The lead storage battery 1 according to the first embodiment of the present invention, the lead storage battery 1 'according to the second embodiment of the present invention, and the lead storage battery of the comparative example shown below are prepared, and the present invention is evaluated by an evaluation test described later. The effect of was confirmed. The batteries of the present invention and the comparative example are both 80D26 type lead acid batteries (hereinafter referred to as batteries) as defined in JIS D5301: 2006 (lead acid battery for starting). Further, in Example 1, an expanded lattice using lead-0.07 mass% calcium-1.6 mass% tin alloy was used for the positive electrode plates of all batteries, and lead-0.07 was used for the negative electrode plates. An expanded lattice using a mass% calcium-0.3 mass% tin alloy was used.

  The structure of the electrode plate group is a structure in which a negative electrode plate is housed in a bag-like microporous polyethylene separator, and seven bag-packed negative electrode plates and seven positive electrode plates are laminated. As the lead, a lead-2.5 mass% tin alloy whose antimony content was limited to less than 0.001 wt% was used. Moreover, about the pole pole and the connection body, lead-2.5 mass% antimony-0.2 mass% arsenic alloy was used.

(Battery A1 of the present invention example)
The battery A1 of the present invention example is a lead storage battery according to the first embodiment of the present invention shown in FIGS. The top surface 21c of the liquid spigot 21 is a circle having a diameter of 25.0 mm, and the depth dimension h is from the circle center (center of the top surface 21c) to the center of the circle from the circumference of 5.0 mm. A large depressed portion 21d was formed. The distance from the bonding surface between the center of the depressed top surface 21c and the lid 7 of the sheet 23, that is, the maximum value of the depth dimension h is 0.5 mm. The exhaust hole 22 is provided with a diameter of 1.0 mm at a position 2.0 mm from the center of the top surface 21c.

  The sheet 23 is a sheet made of PET resin and having a thickness of 0.10 mm, and an acrylic emulsion-based adhesive (adhesive layer thickness 20 μm) was used as a bonding agent with the lid 7. The length of the slit 25a forming the intersecting slit 25 is 7.0 mm, and the two slits 25a intersect each other at right angles in a cross shape at the respective length centers. The intersecting portion of the intersecting slit 25 is at a position corresponding to the depressed portion 21d, and the depth dimension of the gap portion 26 from the intersecting portion of the intersecting slit 25 to the top surface 21c of the liquid spigot 21 is 1.0 mm. It is. The cross slit 25 was formed using a Thomson blade having a cross-shaped tip.

(Battery A2 of the present invention example)
In the battery A2 of the present invention, the shape of the top surface 21c of the liquid spigot 21 of the battery A1 is the shape shown in FIG. 5, and other specifications are the same as the battery A1.

  That is, the part of the top surface 21c that is formed with a step in the part of the top surface 21c that is formed on the piece 25c is depressed, and the part of the top surface 21c that is formed with the depression of the top surface 21c. The depth dimension was 0.3 mm. When the battery A of the present invention is viewed from the top surface, the depression formed on the top surface 21c of the liquid spigot 21 appears in a circular shape with a radius of 5 mm from the center of the top surface 21c, and is depressed within this circumference, that is, the depression. An exhaust hole 22 is opened in a gap portion 26 formed by the portion.

(Battery A3 of the present invention example)
In the battery A3 of the present invention, the shape of the top surface 21c of the liquid spigot 21 of the battery A1 and the battery A2 of the present invention is the shape shown in FIG. 6, and other specifications are the battery A1. And it is not different from battery A2.

  In the battery A3, the top surface 21c of the liquid spout 21 is formed in a flat shape, and is recessed with a depth dimension h from the bonding surface 7b of the lid 7 with the sheet 23, whereby the top surface 21c. A gap 26 is formed between the sheet 23 and the sheet 23. In addition, the depth dimension h of the gap portion 26 in the battery A3 of the example of the present invention is 0.2 mm.

(Battery A4 of the present invention)
In the battery A4 of the present invention, a U-shaped bent slit 25 ′ having two bends shown in FIG. 7 was formed on the sheet 23 in place of the cross slit 25 used in the battery A1 of the present invention. Is. The bent slit 25 ′ has a U-shaped height of 2.0 mm and a U-shaped width of 3.0 mm, and a U-shaped Thomson blade is pressed against the sheet 23. Formed.

  The piece 25'c and the exhaust hole 22 formed by the bent slit 25 'are formed at positions corresponding to the gap portion 26, and the piece 25'c is bent and deformed in the direction of the liquid spout 21 to thereby bend the slit. 25 'opens.

(Battery A5 of the present invention)
In the battery A5 of the present invention, a bent slit 25 'employed in the battery A4 of the present invention is formed on the sheet 23 in place of the cross slit 25 used in the battery A2 of the present invention. Same as A2.

(Battery A6 of the present invention)
In the battery A6 of the present invention, a bent slit 25 'employed in the battery A4 and the battery A5 of the present invention is formed in the sheet 23 in place of the cross slit 25 used in the battery A3 of the present invention. The specification is the same as battery A3.

(Comparative battery B1)
The battery B1 of the comparative example is a battery in which the dimension h shown in FIG. 6 is 0.0 mm in the battery A3 of the example of the present invention shown in FIG. 6, and the space between the top surface 21c and the sheet 23 is designed. A gap corresponding to the thickness of the pressure-sensitive adhesive layer that joins the sheet 23 and the lid 7 exists. However, as described above, the thickness of the pressure-sensitive adhesive layer is 20 μm, and the thickness is not sufficient to open the slit 25a by bending the piece 25c downward.

(Comparative battery B2)
The battery B2 of the comparative example is obtained by replacing the cross slit 25 formed in the sheet 23 with the bent slit 25 'used in the battery A4, battery A5 and battery A6 of the present invention in the battery B1 of the comparative example described above. The other configuration is not changed to the battery B1 of the comparative example.

(Comparative battery C1)
The battery C1 of the comparative example is obtained by replacing the cross slit 25 formed in the sheet 23 with the two parallel slits 30 arranged in parallel to each other as shown in FIG. 8 in the battery A1 of the present invention. is there. The parallel slit 30 has a configuration in which two slits having a length of 3.0 mm are arranged in parallel at an interval of 1.5 mm, and a region sandwiched between the two slits corresponds to the gap portion 26. Placed in position. The battery C1 is the same as the battery A1 of the present invention except for the parallel slit 30.

(Comparative battery C2)
The battery C2 of the comparative example is obtained by replacing the cross slit 25 formed in the sheet 23 with the two parallel slits 30 arranged in parallel as shown in FIG. 8 in the battery A2 of the present invention example. is there. The parallel slit 30 has a configuration in which two slits having a length of 3.0 mm are arranged in parallel at an interval of 1.5 mm, and a region sandwiched between the two slits corresponds to the gap portion 26. Placed in position. The battery C2 is not different from the battery A2 of the present invention except for the parallel slit 30.

(Comparative battery C3)
The battery C3 of the comparative example is obtained by replacing the cross slit 25 formed in the sheet 23 with the two parallel slits 30 shown in FIG. is there. The parallel slit 30 has a configuration in which two slits having a length of 3.0 mm are arranged in parallel at an interval of 1.5 mm, and a region sandwiched between the two slits corresponds to the gap portion 26. Placed in position. The battery C3 is the same as the battery A3 of the present invention except for the parallel slit 30.

(Comparative battery D1)
The battery D1 of the comparative example is obtained by replacing the cross slit 25 formed on the sheet 23 with the two parallel slits 30 arranged in parallel to each other as shown in FIG. 8 in the battery B1 of the comparative example described above. . The parallel slit 30 has a configuration in which two slits having a length of 3.0 mm are arranged in parallel at an interval of 1.5 mm, and a region sandwiched between the two slits corresponds to the gap portion 26. Placed in position. The battery D1 is the same as the battery B1 of the comparative example except for the parallel slit 30.

  Table 1 shows the specifications of each battery described above.

  Each battery shown in Table 1 was vibrated in the vertical direction at an acceleration of 1 G (30 Hz) while continuously charged for 2000 hours at a charging voltage of 15.0 V (maximum charging current 25 A) in a temperature atmosphere of 60 ° C. In this operation, each battery is intentionally overcharged, and mist of water vapor is intentionally attached around the exhaust hole 22 provided in the liquid spout 21, and the liquid spout 21 and the sheet 23 are condensed with mist. This was carried out in order to make it easy to stick due to the generated moisture.

  Next, each battery subjected to the above overcharge operation was 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.

  As a result, in all batteries, although the internal pressure of the battery is increased, when the internal pressure increases from atmospheric pressure (101.325 kPa) to 10 kPa to 20 kPa, the gas in the battery opens each slit, and the internal pressure is atmospheric pressure. It dropped to. In addition, in each battery, deformation of the partition walls and the battery case due to internal pressure, which would be an obstacle to the use of the battery, was not recognized.

  Next, the minimum value of the battery internal pressure and the liquid level state of each cell when each battery was left at room temperature of 25 ° C. for 24 hours were confirmed. In this test, by changing the battery temperature from high temperature to room temperature, the internal volume of the battery is reduced from atmospheric pressure by reducing the volume of gas present inside the battery, and the sheet 23 and the lid 7 at that time The reduced pressure state of the battery internal pressure by sticking and the liquid level state of each cell are evaluated. In such a test, after the engine vehicle is used, the end user starts using the lead storage battery after the lead storage battery is formed and charged in a use mode in which the vehicle is parked or in the manufacturing process of the lead storage battery. It is a form that cannot be avoided in the manufacturing process of the lead storage battery and its use mode.

  The maximum and minimum values of the internal pressure of the six cell chambers constituting each battery after being allowed to stand at 25 ° C. for 24 hours, the presence or absence of deformation of the partition walls between the cell chambers, and the liquid level difference between the cells were measured. . The results are shown in Table 2. In Table 2, the cell internal pressure is indicated by a value obtained by subtracting the atmospheric pressure at the time of measurement from the actual internal pressure. Therefore, when the cell internal pressure is 0 kPa, the cell internal pressure is equal to the atmospheric pressure. When the cell internal pressure exceeds 0 kPa, the cell internal pressure is in a pressurized state with respect to the atmospheric pressure, and when the cell internal pressure is a negative value less than 0 kPa, the cell internal pressure is It can be seen that the pressure is reduced with respect to the atmospheric pressure.

  From the results shown in Table 2, in the battery of the comparative example, when the battery was cooled to room temperature after being charged, the internal pressure of the cell was reduced to a pressure lower than the atmospheric pressure, and the reduced pressure was different between the cells. As a result, the partition wall was deformed, resulting in a difference between the cells in the internal volume of the cell, and a large difference in the electrolyte surface. In the present example, since the initial electrolyte surface was adjusted to the upper limit line, some cells had the electrolyte surface greatly exceeding the upper limit line. In such a battery, the electrolyte easily leaks due to charging or vibration.

  Moreover, in the present Example, although the initial electrolyte level was adjusted to the upper limit line, when it was adjusted to the lower limit line, the battery of the comparative example generated a battery whose electrolyte level was significantly lower than the lower limit line. The lower limit line is set at a position above the upper surface of the negative electrode strap in this embodiment and, as is widely known. This is to prevent the negative electrode strap from being exposed from the electrolyte surface and being broken by corrosion. Therefore, in the battery of the comparative example, when the electrolytic solution level was significantly below the lower limit line, the negative electrode strap was exposed from the electrolytic solution, and further, the negative electrode plate was exposed from the electrolytic solution surface. Such a phenomenon causes problems such as corrosion of the negative electrode strap and a decrease in battery capacity due to oxidation deterioration of the negative electrode plate.

  On the other hand, in the battery of the present invention, the cells are not in a reduced pressure state, and as a result, the internal pressure variation in the reduced pressure state, the deformation of the partition walls and the fluctuation of the electrolyte surface due to this are suppressed.

  That is, when the slit is crossed or bent, a piece is formed on the sheet, and when the internal pressure of the cell is reduced by forming a gap that can be bent and deformed downward, the piece is bent downward. A remarkable effect is obtained that the slit is deformed and the cell is decompressed, and the above-described problems caused by the decompression of the cell can be eliminated.

  Even when a piece is formed on the sheet, the effect of the present invention cannot be obtained if there is no gap that allows the piece to bend and deform downward.

  Even if a gap that can be bent and deformed downward is provided, a slit that does not form a piece, such as a parallel slit or a single slit, does not open even by decompression, and the effect of the present invention cannot be obtained.

  In this example, a lead-tin alloy in which the content of antimony is limited to the level of inevitable impurities was used for the negative electrode strap and the positive electrode strap, but instead of this lead-tin alloy, it has been widely used as a strap alloy. A lead-antimony (-arsenic) -based alloy that has been used can be used, and it was confirmed by a separate experiment that the use of this alloy for a strap does not impair the effects of the present invention.

  However, when the lead-antimony alloy is a positive and negative strap alloy, the amount of liquid reduction is increased by about 20% to 50% compared to the batteries of the examples. Then, since the main purpose of covering the exhaust hole with the sheet is to suppress liquid reduction, as shown in the above-described embodiment, the antimony content is 0.001% by mass in the positive and negative straps. It is obvious that it is preferable to use a lead alloy which does not contribute to an increase in the amount of liquid reduction and is limited to an inevitable impurity level.

  The present invention can be applied to liquid lead acid batteries for various uses, including lead acid batteries for starting.

DESCRIPTION OF SYMBOLS 1, 1 'Lead acid battery 2 Positive electrode plate 3 Negative electrode plate 4 Separator 5 Electrolyte 6 Electrolyte 6a Cell chamber 6b Partition 7 Lid 7a Liquid port 7b Bonding surface 8 Electrode plate group 9 Positive electrode strap 10 Negative electrode strap 11 Terminal 12 Electrode column 13 Connector 21 Liquid stopper 21a Splash-proof body 21b Filter 21c Top surface 21d, 21'd Depressed part 22 Exhaust hole 23 Sheet 23a, 23'a, 23 "a Non-joining part 25 Crossing slit 25 'Bending slit 25a Slit 25c Piece 25'c piece 26 gap 30 parallel slit

Claims (3)

The positive electrode plate and the negative electrode plate are arranged via a separator,
A group of electrode plates in which the electrode plate ears of the same polarity are collectively welded with a positive electrode strap and a negative electrode strap,
A battery case in which a plurality of cell chambers containing the electrode plate group and the electrolyte are partitioned by partition walls;
A lid joined to the opening of the battery case;
A lead storage battery having a liquid port plug provided with an exhaust hole for discharging the gas in the battery case to the outside of the battery while being attached to a liquid port provided in the lid corresponding to the cell chamber There,
A sheet adhered to the lid by a bonding agent such as an adhesive or an adhesive so as to cover the exhaust hole,
The sheet has flexibility;
The bonding surface of the sheet and the lid is provided with a non-joining portion that does not have the bonding agent,
The non-joining part is formed so as to exhaust the exhaust gas from the exhaust hole through the gap between the lid and the sheet to the outside of the battery at a position spaced from the exhaust hole,
Forming a cross slit in which a plurality of slits cross each other at a position facing the liquid spigot of the sheet;
And by making the part facing the piece formed by the slits intersecting the top surface of the liquid spigot rather than the bonding surface of the lid to the sheet, the top surface and the sheet With a gap between
The lead-acid battery is characterized in that the exhaust hole is provided at a position corresponding to the gap. The positive electrode plate and the negative electrode plate are arranged via a separator,
A group of electrode plates in which the electrode plate ears of the same polarity are collectively welded with a positive electrode strap and a negative electrode strap,
A battery case in which a plurality of cell chambers containing the electrode plate group and the electrolyte are partitioned by partition walls;
A lid joined to the opening of the battery case;
A lead storage battery having a liquid port plug provided with an exhaust hole for discharging the gas in the battery case to the outside of the battery while being attached to a liquid port provided in the lid corresponding to the cell chamber There,
A sheet adhered to the lid by a bonding agent such as an adhesive or an adhesive so as to cover the exhaust hole,
The sheet has flexibility;
The bonding surface of the sheet and the lid is provided with a non-joining portion that does not have the bonding agent,
The non-joining part is formed so as to exhaust the exhaust gas from the exhaust hole through the gap between the lid and the sheet at a position spaced from the exhaust hole and out of the battery.
Forming a bent slit having a bend at a position facing the liquid plug of the sheet;
And by making the part facing the piece formed by the bending slit of the top surface of the liquid spigot recessed from the bonding surface of the lid with the sheet, the top surface and the sheet A gap between them,
The lead-acid battery is characterized in that the exhaust hole is provided at a position corresponding to the gap. 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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