JP2013191351A - Lead acid battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lead acid battery stably which is highly durable against rough roads even when the deadweight of its electrode plate group is increased in order to improve volumetric efficiency and extend life.SOLUTION: In the lead acid battery, a plurality of electrode plate groups with the cathode and anode opposed via a separator are housed in respective cell chambers of a battery case made of resin which is divided into a plurality of cell chambers by a partition plate in such a way that the partition plate and the cathode and anode are parallel to each other, where different poles of adjacent electrode plate groups are connected together in series with a lead component and the poles among electrode plate groups at opposite ends which are not connected with the lead component have pole columns connected thereto. A ratio T/W of the thickness Tmm of an outer wall on short side face side parallel to the partition plate among outer walls of the battery case to the weight Wkg of the electrode plate groups is made to be 2.2 mm/kg or more.

Description

  The present invention relates to a lead storage battery used as a cell starter.

  A lead storage battery used for a cell starter, etc., is a resin battery case in which a plurality of electrode plate groups in which a positive electrode and a negative electrode are opposed to each other via a separator are divided into a plurality of cell chambers by a partition plate. In the chamber, the partition plate and the positive electrode and negative electrode are stored in parallel, the different polarities of the adjacent electrode plate groups are connected in series with lead parts, and the lead parts of the electrode plate groups at both ends are connected with lead parts. It is constructed by connecting polar poles to the polarity that was not done.

  It is required to improve durability (rough road durability) when a vehicle equipped with this lead storage battery is driven on a rough road such as unpaved road. In such a case, as mentioned in Patent Document 1, it is possible to increase the bad road durability of the lead storage battery by making the lower part of the battery case side into a tapered shape and bringing the electrode plate group into contact therewith. Conceivable.

Japanese Patent Laid-Open No. 01-006357

  However, in recent years, the volume efficiency (battery capacity under a certain volume) is improved and the life is increased by increasing the number of electrode plates (positive electrode and negative electrode) of the lead storage battery and the active material filling amount per electrode plate. Attempts have been made. This attempt increases the weight of the electrode plate group. When the dead weight of the electrode plate group of the lead storage battery is increased, the stress at the time of vibration is increased accordingly, so that the rough road durability is lowered. That is, attempts to increase the number of electrode plates of lead-acid batteries and the amount of active material filling per electrode plate are contrary to the desire to improve rough road durability. The bad road durability of a lead-acid battery with increased weight of the electrode plate group is not improved.

  The present invention is to solve the above-mentioned problems, and to provide a lead-acid battery having high durability against rough roads even if the weight of the electrode plate group is increased for the purpose of improving the volume efficiency and extending the life. Objective.

  In order to solve the above problems, the invention according to claim 1 is a resin product in which a plurality of electrode plate groups in which a positive electrode and a negative electrode are opposed to each other through a separator are divided into a plurality of cell chambers by an intermediate partition plate. In each cell chamber of the battery case, the partition plate and the positive electrode and the negative electrode are stored in parallel, and different polarities of adjacent electrode plate groups are connected in series with lead parts, and the electrode plates at both ends A lead storage battery in which polar columns are connected to polarities not connected by lead parts in the group, and the thickness Tmm of the outer wall of the short side parallel to the partition plate of the outer wall of the battery case and the weight of the electrode plate group The ratio T / W with Wkg is set to 2.2 mm / kg or more.

  The invention according to claim 2 is characterized in that, in claim 1, the ratio T / W is 3.1 mm / kg or less.

  The invention according to claim 3 is characterized in that, in claim 1, the lead component and / or the pole column is made of a Pb—Sn alloy.

  The invention according to claim 4 is characterized in that, in claim 1, the ratio T / t between the thickness Tmm of the short side wall and the thickness tmm of the partition plate is 2.3 or more.

  The invention according to claim 5 is characterized in that, in claim 4, the ratio T / t is 3.4 or less.

  Even in the case of adopting a structure in which the electrode plate group is sandwiched by a tapered shape provided at the lower part of the side surface of the battery case as in Patent Document 1, the direction different from the direction shown in Patent Document 1 (electrode plate width direction) is 90 °. The effect is small when vibration is applied to the electrode plate group stacking direction. In addition, when the weight of the electrode plate group increases and strong vibration is applied in this direction, the outer wall on the short side of the battery case bends and the gap between the electrode plate groups on both ends in contact with the outer wall on the short side exceeds the design value. The present inventors have newly found that the vibration resistance is further deteriorated by spreading.

  In order to suppress the bending of the outer wall on the short side surface described above, the outer wall on the short side surface itself may be made thicker. However, as a result of intensive studies by the present inventors, the following two things were further found out.

  First, the thickness T (mm) effective for suppressing the bending of the outer wall on the short side surface is proportional to the weight W (kg) of the electrode plate group that is the basis of vibration. That is, the parameter for obtaining the effect of the present invention is not simply the thickness T (mm) of the outer wall on the short side surface, but the ratio T / W (mm / kg) obtained by dividing T by the weight W (kg) of the electrode plate group. )

  Secondly, since the middle partition plate itself is sandwiched between the electrode plate groups, it is difficult to bend even when vibration is applied in the stacking direction of the electrode plate groups. That is, the thickness of the partition plate is not considered as a parameter for obtaining the effect of the present invention, but if this thickness is inadvertently too large, another problem will be caused as described later.

  The present invention is established by fully utilizing the above-described plurality of findings.

  According to the present invention, it is possible to provide a lead-acid battery having a high rough road durability even if the weight of the electrode plate group is increased in order to improve volumetric efficiency and extend the life.

The figure which shows the lead acid battery of this invention The figure which shows the effect of this invention

  Hereinafter, a preferred example of an embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 is a view showing a lead storage battery of the present invention. A plurality of electrode plate groups 1 in which the positive electrode 1a and the negative electrode 1b are opposed to each other with the separator 1c interposed between the cell chambers 2c of the resin battery case 2 divided into the plurality of cell chambers 2c by the intermediate partition plate 2b. The intermediate partition plate 2b, the positive electrode 1a, and the negative electrode 1b are housed in parallel. Then, different polarities of the adjacent electrode plate groups 1 are connected in series by the lead component 3, and the pole 4 is connected to a polarity not connected by the lead component in the electrode plate group 1 at both ends. Furthermore, the opening of the battery case 2 is sealed with a lid 5, and a predetermined amount of electrolyte (dilute sulfuric acid) is added to each cell chamber 2c to perform initial charging under predetermined conditions.

  The lead storage battery of the present invention has a ratio T / W of 2.2 mm / kg between the thickness Tmm of the short side outer wall 2a parallel to the middle partition plate 2b and the weight Wkg of the electrode plate group 1 in the outer wall of the battery case 2. It is characterized by the above. When the own weight of the electrode plate group 1 is increased and strong vibration is applied in the stacking direction of the electrode plate group 1, the short side surface outer wall 2a of the battery case 2 is bent and the electrode plate groups at both ends contacting the short side surface outer wall 2a. As the gap with 1 widens beyond the design value, the vibration resistance is extremely deteriorated. In the present invention, in order to suppress this bending, the battery case 2 itself including the short-side outer wall 2a is not simply thickened, but the following two new findings shown below are utilized.

  First, based on the fact that the thickness T (mm) effective for suppressing the bending of the outer wall 2a on the short side surface is proportional to the weight W (kg) of the electrode plate group 1 as the basis of vibration, the short side surface is simply set. This is not the thickness T (mm) of the side outer wall 2a but the ratio T / W (mm / kg) obtained by dividing this T by the weight W (kg) of the electrode plate group 1 as a parameter.

  Second, since the middle partition plate 2b itself is sandwiched between the electrode plate groups 1, the thickness of the middle partition plate 2b is determined based on the fact that it is difficult to bend even when vibration is applied in the stacking direction of the electrode plate group 1. This is not considered as a parameter for obtaining the effect of the present invention.

  However, if the ratio T / W exceeds 3.1 mm / kg, the short side wall 2a becomes too thick. Therefore, if the battery case 2 does not exceed the standard size, the cell chamber 2c is slightly The capacity of the electrode plate group 1 is slightly reduced during production.

  The Pb—Sn alloy has a higher corrosion resistance than the Pb—Sb alloy, but the mechanical strength is weak and the plastic deformation is likely to occur, so that the vibration resistance is inferior. However, if a Pb—Sn alloy is used for the lead component 3 and / or the pole column 4 in the present invention, the effects of the present invention increase the vibration resistance and show high corrosion resistance, so that the overall performance of the lead storage battery is enhanced. become. That is, the lead storage battery of the present invention using the Pb—Sn alloy for the lead part 3 and / or the pole 4 is more resistant to the lead storage battery using the Pb—Sb alloy for the lead part 3 and / or the pole 4. The vibration resistance is equivalent and the corrosion resistance is high.

  Moreover, in this invention, it is more preferable if ratio T / t of thickness Tmm of the short side outer wall 2a and thickness tmm of the partition plate 2b shall be 2.3 or more. When this ratio is as small as less than 2.3 (relatively large thickness t of the partition plate 2b), the cell chamber 2c is first slightly narrowed and the storage capacity of the electrode plate group 1 is slightly lowered during production. Furthermore, poor welding is likely to occur due to the influence of the thick partition plate 2b when the lead parts 3 connected to the adjacent electrode plate group 1 are welded to each other. On the other hand, when the ratio T / t is larger than 3.4 (the thickness t of the partition plate 2b is relatively small), mold releasability when the battery case 2 is molded is slightly lowered. , Which tends to cause an increase in production costs.

  The effect of the present invention is not affected by the thickness of the outer wall 2d on the long side surface of the battery case 2.

  As an active material paste for the positive electrode 1a and the negative electrode 1b, a synthetic resin fiber having various resistance to sulfuric acid and various additives are added to a mixed powder of lead and lead oxide and kneaded with water and dilute sulfuric acid. . Of these, red lead can be added to the active material paste (positive electrode active material paste) used for the positive electrode 1a for the purpose of improving the efficiency of chemical conversion and improving the initial capacity characteristics. In addition, the active material paste (negative electrode active material paste) used for the negative electrode 1b reacts as a generation nucleus of a lignin compound or a discharge reaction product (lead sulfate) that suppresses volume change (shrinkage or expansion) of the active material of the negative electrode 1b. Add barium sulfate, which has a function of homogenizing. Then, an expanded lattice made of various lead alloys (lead-calcium alloy, lead-tin alloy, etc.) is filled with the above-mentioned positive electrode active material paste and negative electrode active material paste, respectively, and paste paper for the purpose of preventing the active material from falling off Is applied to these surfaces to produce the positive electrode 1a and the negative electrode 1b.

  A glass mat etc. can be used for the separator 1c.

  The electrode plate group 1 in the present invention includes the positive electrode 1a, the negative electrode 1b, the paste paper applied to the surfaces of the positive electrode 1a and the negative electrode 1b, and the separator 1c. The weight W ( kg) includes a positive electrode 1a, a negative electrode 1b, and a separator 1c. The positive electrode 1a and the negative electrode 1b vary in weight depending on the state of charge (SOC), and the weight of the electrode group 1 varies depending on the SOC. However, in the present invention, the SOC is 100%. In this case, the weight W (kg) of the electrode plate group 1 is used. Further, the positive electrode 1a and the negative electrode 1b also include protrusions for joining with the lead component 3 called electrode plate ears.

  Next, the effect of the lead storage battery of the present invention will be described in further detail using examples.

  The positive electrode group 1 having a weight of 1.93 kg was formed by wrapping eight positive electrodes 1a produced by the above-described method in a U shape with glass mat separators 1c and alternately combining with nine negative electrodes 1b. .

This electrode plate group 1 was accommodated in each cell chamber 2c of various battery cases 2 shown in (Table 1). Adjacent electrode plate groups 1 are connected in series with a lead component 3 made of a Pb—Sn alloy having a Sn content of 2.5% by weight (wherein the lead storage battery A13 is a Pb—Sb alloy having a Sb content of 2% by weight). A pole 4 made of a Pb—Sn alloy having a Sn content of 6% by weight is connected to the polarity not connected by the lead component 3 in the electrode plate group 1 at both ends (however, the lead storage battery A13 has a Sb content of 2%). % Pb—Sb alloy). Further, the opening of the battery case 2 is sealed with the lid 5, and a predetermined amount of electrolyte (diluted sulfuric acid with a specific gravity of 1.285 g / cm ³ ) is added to each cell chamber 2c, and initial charging under predetermined conditions is performed. Lead storage batteries A01 to A15 called D23 in JIS 8501 were produced. The results of various evaluations (conditions are described in detail below) for these batteries are also shown in Table 1.

(Vibration resistance)
Each battery in a fully charged state was discharged at 0.05 C while continuously applying vibration with an acceleration of 24.5 m / s ² and an amplitude of 2.4 mm in the stacking direction of the electrode plate group 1. The time until the internal energization structure is disturbed and the discharge curve becomes unstable is shown in Table 1 as an index with the lead storage battery A01 as 1.0 (for lead storage batteries A01 to A08 in FIG. 2). Also noted).

(Insertability of electrode group 1)
The damage of the electrode plate group 1 when the electrode plate group 1 was manually stored in the cell chamber 2c was evaluated. What was stored without resistance was “◎◎”, and what was stored without problems was “◎”, but was able to be stored without damaging the electrode plate group 1 even though it was caught several times. A case where “◯” is given, and a case where there is a large resistance and slight breakage of the electrode plate group 1 is shown as “Δ” in Table 1.

(Component yield)
The yield of the battery case 2 in consideration of defects during molding is shown in (Table 1).

(Corrosion resistance)
In accordance with SBA S0101 9.4.5 “Idling Stop Life”, a life test of idling stop where charging and discharging are frequently performed was performed. When the electrode plate ear is not corroded at the end of its life, “◎” indicates that the electrode plate ear has not been broken, but when it is corroded, “Δ” indicates it in (Table 1).

  As can be seen from the results of A01 to A08 (see also FIG. 2), the ratio T / W of the thickness T (mm) of the short side wall 2a and the weight W (kg) of the electrode plate group 1 is 2.2. If it is (mm / kg) or more, it turns out that the lead storage battery excellent in vibration resistance can be provided. However, when the ratio T / W exceeds 3.1 (mm / kg), the insertion capacity of the electrode plate group 1 is slightly lowered due to a decrease in the internal volume of the cell chamber 2c.

  As can be seen from the results of A06 and A09 to A12, the thickness t (mm) of the partition plate 2b is reduced for the purpose of solving the above-described problem (securing the internal volume of the cell chamber 2c), and consequently T / t is obtained. When the battery case 2 exceeding 3.4 is molded, the mold separability is slightly lowered, and the yield is slightly lowered. Conversely, when the thickness t (mm) is increased and, as a result, T / t is less than 2.3, the above-described problem (decrease in insertability of the electrode plate group 1) is observed.

  As can be seen from the results of A06 and A13 to A17, the corrosion resistance is improved by using a Pb—Sn alloy instead of the Pb—Sb alloy as the lead component 3 and the pole 4.

  As can be seen from the results of A06, A18, and A19, the thickness of the long side surface outer wall 2d does not affect the effect of the present invention.

  In place of each of A01 to A15 in Example 1, a lead storage battery having the constitutional conditions shown in (Table 1) (referred to as D26 in JIS 8501 / the weight of the electrode plate group 1 is 2.16 kg) was used. Except for the above, lead storage batteries B01 to B15 were produced in the same manner as in Example 1, and the same evaluation as in Example 1 was performed. These are shown in (Table 2). Further, the effect of the ratio T / W on the vibration resistance in the lead storage batteries B01 to B08 is also shown in FIG. 2 as an index with the lead storage battery B01 as 1.0.

  The evaluation result of Example 2 showed the same tendency as Example 1. As should be noted from the comparison between Examples 1 and 2, as can be seen from FIG. 2, the effect of the present invention is not simply the thickness T (mm) of the short side wall 2a, but this T is used for the electrode plate group 1. It is based on the ratio T / W (mm / kg) divided by the weight W (kg) of (the same applies to the ratio T / t). This shows that the present invention can be widely applied without being influenced by the size of the lead storage battery.

  By utilizing the present invention, it is possible to provide a lead storage battery having high durability against rough roads even when the weight of the electrode plate group is increased, so that not only the industrial applicability is high, but also its usefulness is Extremely expensive.

DESCRIPTION OF SYMBOLS 1 Electrode plate group 1a Positive electrode 1b Negative electrode 1c Separator 2 Battery case 2a Short side surface outer wall 2b Middle partition plate 2c Cell chamber 2d Long side surface side outer wall 3 Lead component 4 Polar pillar 5 Lid

Claims (5)

A plurality of electrode plate groups in which a positive electrode and a negative electrode are opposed to each other via a separator are divided into a plurality of cell chambers made of resin divided into a plurality of cell chambers by an intermediate divider plate. Are connected in parallel, different polarities of adjacent electrode plate groups are connected in series with lead components, and pole columns are connected to polarities that are not connected with lead components in the electrode plate groups at both ends. Lead acid battery,
A ratio T / W between a thickness Tmm of the outer wall of the short side surface parallel to the inner partition plate and the weight Wkg of the electrode plate group in the outer wall of the battery case is set to 2.2 mm / kg or more. Lead acid battery. The lead acid battery according to claim 1, wherein the ratio T / W is 3.1 mm / kg or less. The lead acid battery according to claim 1, wherein the lead component and / or the pole column is made of a Pb-Sn alloy. 2. The lead acid battery according to claim 1, wherein a ratio T / t of a thickness Tmm of the outer wall on the short side surface and a thickness tmm of the intermediate partition plate is set to 2.3 or more. The lead storage battery according to claim 4, wherein the ratio T / t is 3.4 or less.

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