JP2009224248A - Lead storage battery - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve a problem that an end portion which is not enveloped catches a rib of a separator and damages a separator base to cause a short circuit of a lead storage battery when a plurality of electrode plates are aligned by using electrode plates housed in an envelope type separator having rib-shaped portions on an external surface when an electrode plate group is composed. <P>SOLUTION: On an external surface of an envelope type separator housing electrode plates, there are provided ribs on corresponding electrode plates, and large ribs exist in an upward and downward direction, and the large rib neighboring a small rib has a long inclined portion provided toward a direction of a center of the separator, and a damage on the separator caused by a catch during an electrode alignment process in order to compose an electrode plate group is prevented. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a lead-acid battery.

  Lead-acid batteries are configured by storing one of a positive electrode plate and a negative electrode plate filled with an active material in a lattice body in a separator made of a microporous synthetic resin sheet in a bag shape, and creating an electrode plate group. The reason why the electrode plate is stored in the bag-shaped separator is to prevent a short circuit at the bottom of the electrode plate and the electrode plate side due to falling off of the active material during use. Either the positive electrode plate or the negative electrode plate is used as the bag-shaped separator. Whether it is arranged inside is determined according to the use of the lead storage battery.

  When the positive electrode plate is packed with a polyethylene separator that is widely used as a microporous synthetic resin, the lattice body extends due to the oxidative degradation of the positive electrode plate. The edge breaks the PE separator, contacts the negative electrode plate, causes a short circuit phenomenon, and causes an early life.

  In recent years, electronic devices such as air conditioners and car navigation systems are installed in automobiles one after another, and there is a harsh environment for starting lead-acid batteries. Therefore, further improvement of the life of lead-acid batteries is desired. For this reason, since the negative electrode plate is not extended by corrosion due to the lattice during use, the lead storage battery in which the negative electrode plate is accommodated in the bag-like separator can have a longer life than the lead storage battery in which the positive electrode plate is accommodated.

  On the other hand, since the positive electrode plate requires a larger amount of electrolyte than the negative electrode plate in the discharge reaction, when the negative electrode plate is stored in the bag-shaped separator, a high rib is provided on the outer surface of the bag-shaped separator in the vertical direction. The electrolyte solution for the positive electrode active material is secured by facing the electrode.

  The presence of ribs on the outer surface of the bag-like separator is because the end of the positive electrode plate or negative electrode plate is caught by the ribs in the step of aligning the electrode plates when the electrode plate group is configured, and the base of the separator is adjusted by forcibly aligning them. It can be damaged and, in the worst case, can pierce the base. In particular, when the rib is opposed to the positive electrode plate, the rib becomes high, and this phenomenon is likely to occur.

In order to prevent damage to the separator, in Patent Document 1, most of the ribs existing at the center in the width direction are provided in the vertical direction, and the small ribs are disposed obliquely at both ends in the width direction. The small ribs are not caught. However, if the width of the small ribs is increased, the electrical resistance of the separator is increased, so that the width cannot be increased and a great effect cannot be obtained.
JP 2000-173575 A

  However, at the time of electrode plate group configuration as described above, when aligning a plurality of electrode plates using electrode plates housed in a bag-like separator having a rib shape on the outer surface, the end of the electrode plate that is not packaged As a result of the part being caught by the rib of the separator and damaging the separator base, a short circuit phenomenon occurred early, and the lead storage battery had a problem that the life performance could not be sufficiently exhibited.

  In order to solve the above-mentioned problem, the invention according to claim 1 of the present invention is the lead-acid battery in which the positive electrode plate or the negative electrode plate is accommodated in the bag-shaped separator using the microporous synthetic resin sheet. A large rib is provided in the vertical direction at most of the central portion in the width direction on the outer surface, and small ribs are formed lower in the vertical direction at both ends in the width direction than the large rib. The adjacent large rib has an inclined portion that reaches an integral part with the outer surface portion, and has a length a to the center corresponding to the inclined portion and a length b corresponding to the end in the width direction. The relationship shows a lead storage battery characterized by a> b.

  The invention according to claim 2 of the present invention shows the lead-acid battery according to claim 1, wherein the negative electrode plate is housed in the bag-shaped separator.

  The invention according to claim 3 of the present invention is the large rib adjacent to the small rib, the large rib occupying most of the central portion, and the small rib. The height of the rib is large rib ≧ small rib 2. The lead-acid battery according to claim 1, wherein: large ribs adjacent to> small ribs.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a plan view of a bag-shaped separator, and FIG. 2 is a combination diagram of a bag-shaped separator and an electrode plate. The separator of the lead storage battery uses a microporous synthetic resin, and generally polyethylene is used. The separator is formed into a bag shape by folding a continuous polyethylene sheet wider than the electrode plate width in two and sealing the both ends with the included electrode plate inside.

  The bag-like separator 1 has large ribs 4 provided in the vertical direction at a portion 3 occupying most of the central portion in the width direction on the outer surface 2 and has small ribs 6 in the vertical direction at both end portions 5 in the width direction. The both end portions 5 are formed by providing sealing portions 7 by heat welding or pressure bonding. The rib interval is such that the large rib 4 is wide and the small rib 6 is narrow. The portion of the small rib 6 becomes substantially flat by heating or pressure when the sealing portion 7 is formed.

  In the lead storage battery, the effect of obtaining stable life characteristics can be expected regardless of whether the positive electrode plate 8 or the negative electrode plate 9 is housed in the bag-shaped separator 1. However, since the positive electrode active material requires a large amount of electrolytic solution in the discharge reaction, the negative electrode plate 9 is accommodated in the bag-shaped separator, and the positive electrode plate is in contact with the large rib 4 on the outer side corresponding to the negative electrode plate. 8 is opposed.

  Specifically, when the positive electrode plate 8 and the negative electrode plate 9 having a width of 138 mm and a height of 115 mm are used, the bag-like separator width is 152 mm and the height is 122 mm, the interval between the large ribs 4 is 10 mm, and the interval between the small ribs 6 is Is formed as 1 mm. The sheet thickness of the bag-like separator 1 is 0.2 mm, and the height of the ribs on the outer surface is 0.6 mm for the large rib 4 and 0.2 mm for the small rib 6.

  FIG. 3 shows an enlarged top sectional view of the rib shape according to the present invention. In the small rib 6 and the large rib 4a adjacent to the small rib, the large rib 4a adjacent to the small rib is inclined toward the outer surface 2 of the separator from the apex portion 4b of the large rib adjacent to the small rib toward the center of the separator. A portion a10 is provided, and the length of the inclined portion a10 in the plane from the vertex 4c of the large rib adjacent to the small rib corresponding to the inclined portion a10 to the outer surface 2 is defined as a.

  On the other hand, there is an inclined portion b11 that faces the outer surface 2 in the end direction of the separator from the apex portion 4b of the large rib adjacent to the small rib, and the apex portion of the large rib adjacent to the small rib corresponding to the inclined portion b11 When the length from the apex 4c of the large rib adjacent to the small rib corresponding to 4b to the outer surface 2 is b, the length a in the plane of the separator is formed longer than b. The length b of the inclined portion in the large rib 4a adjacent to the small rib is the same as the length of the inclined portion of the large rib 4 occupying most of the width direction.

  FIG. 4 shows an enlarged top sectional view of another rib shape according to the present invention. The rib shape is the same as that described in FIG. 3, but the height ha from the outer surface 2 of the large rib 4a adjacent to the small rib is higher than the height h of the large rib 4 occupying most of the central portion. Forming low. When the height of the large rib 4 is 0.6 mm, the height of the large rib 4a adjacent to the small rib is 0.4 mm, and the height hb of the small rib 6 is 0.2 mm. Three types of heights are set on both sides of the outer surface 2 of the separator, and the relationship between the heights is represented by large rib> large rib adjacent to small rib> small rib.

  Similarly, the large rib 4a adjacent to the small rib has a length a ′ from the apex portion 4b of the large rib adjacent to the small rib toward the outer surface of the separator toward the center of the separator. It is desirable to make it longer than the corresponding length b.

  FIG. 5 is an explanatory diagram of aligning and combining electrode plates. This is a combination of a bag-shaped separator containing a negative electrode plate 9 and a positive electrode plate 8. The positive electrode plate 8 slides the lower part and faces the electrode plate to one of both end portions 5, and the positive electrode plate end 8 a is outside the bag-shaped separator. It moves while contacting the large rib 4 existing on the surface, and shifts to the combined state of the bag-like separator and electrode plate shown in FIG. However, in the step of actually aligning the electrode plate group, the bag-like separator 1 and the positive electrode plate 8 are combined to some extent in advance, and the positive electrode plate end portion 8a is formed on the large rib 4 during substantial movement. Both ends, that is, slide in contact with the large rib 4a adjacent to the small rib.

  FIG. 6 is an upper cross-sectional conceptual diagram combining the electrode plate and the separator according to the configuration of the present invention. In a state where the negative electrode plate 9 is disposed in the bag-like separator 1, a plurality of large ribs 4 are provided on the outer surface 2 of the bag-like separator 1 so as to face the positive electrode plate 8. Small ribs 6 lower than the large ribs 4 are provided at narrow intervals, and at both end portions 5 are formed in a bag shape by a sealing portion 7 in which two separators are integrated. Although the small rib 6 was initially present in the sealing portion 7, the rib portion has disappeared due to heating or mechanical pressure bonding during sealing.

  With this configuration, the large rib 4a adjacent to the small rib has the inclined portion a10 toward the center of the separator, so that when the positive plate end 8a slides, the positive plate 8 Even if there is some deformation or curvature, the positive electrode plate end 8a can move without being caught by the large rib 4a adjacent to the small rib when contacting the large rib 4a adjacent to the small rib.

  FIG. 7 is a conceptual diagram of an upper cross section in which a conventional electrode plate and a separator are combined. If the large rib 4a adjacent to the small rib does not have an inclined portion in the direction of the center of the separator, the positive electrode plate end 8a is caught at that portion, and is wound into the large rib 4a adjacent to the small rib. When the pressure reaches the outer surface 2 of 1 and the pressure for aligning the positive electrode plate 8 is applied, the bag-shaped separator is broken through the bottom 4d of the large rib adjacent to the small rib.

  According to the configuration of the present invention, the large ribs 4 are provided in most of the central portion in the width direction, and the small ribs 6 are formed lower than the large ribs 4 at both ends in the width direction. The large rib 4a adjacent to the two small ribs is provided with a length corresponding to the inclined portion toward the center of the separator so that the end of the electrode plate is aligned in the step of aligning the electrode plates in the electrode plate group configuration. The large rib 4a adjacent to the small rib is not caught and the width dimension for providing the small rib 6 does not need to be widened. In addition, by forming the large rib 4 a adjacent to the small rib so as to be lower than the large rib 4, the positive plate 8 can be easily slid in both end portions 5.

  In the present invention, the negative electrode plate 9 is accommodated in the bag-shaped separator. However, the same applies when the positive electrode plate 8 is accommodated and the negative electrode plate 9 is opposed to the rib existing on the outer surface 2 of the separator 1. An effect is obtained. Further, the inclined portion a10 has a linear inclination in FIGS. 3 and 4, but the inclined portion may be formed in a curved shape.

  As described above, since the short circuit can be prevented by using the rib shape of the bag-shaped separator of the present invention, a highly reliable lead storage battery can be obtained, which is industrially useful.

Top view of bag separator Combination diagram of bag separator and electrode plate An enlarged top sectional view of a rib shape according to the present invention Expanded top sectional view of another rib shape according to the present invention Explanatory drawing for combining electrode plates The upper cross-section conceptual diagram which combined the electrode plate and separator by the structure of this invention Top cross-sectional conceptual diagram combining conventional electrode plate and separator

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Bag-shaped separator 2 Outer surface 3 Portion which occupies most of center part 4 Large rib 4a Large rib adjacent to small rib 4b Vertex of large rib adjacent to small rib 4c Vertex of large rib adjacent to small rib 4d Small Bottom of large rib adjacent to rib 5 Both ends 6 Small rib 7 Sealing portion 8 Positive plate 8a Positive plate end 9 Negative plate 10 Inclined portion a
11 Inclined part b

Claims (3)

In a lead-acid battery in which a positive electrode plate or a negative electrode plate is housed in a bag-like separator using a microporous synthetic resin sheet, the outer surface of the bag-like separator is large in the vertical direction in the majority of the central portion in the width direction. The ribs are provided and the small ribs are formed lower than the large ribs in the vertical direction of both end portions in the width direction, and the large ribs adjacent to the small ribs are inclined portions that lead to an integrated portion with the outer surface portion. And a relation between a length a to the central portion corresponding to the inclined portion and a length b corresponding to the end portion in the width direction is a> b. The lead acid battery according to claim 1, wherein a negative electrode plate is accommodated in the bag-like separator. In the large rib adjacent to the small rib, and in the large rib and the small rib that occupy most of the central portion, the height of the rib is large rib ≧ large rib adjacent to the small rib> small rib. The lead acid battery according to claim 1.

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