JP7010772B2 - Ribbed separator for lead-acid battery and lead-acid battery using the separator - Google Patents

Description

The present invention relates to an improvement of the rib of a ribbed separator for a lead storage battery and a lead storage battery using the separator.

For a lead-acid battery having a fluid electrolytic solution between the positive and negative electrode plates, as shown in FIG. 4, the length direction is oriented on the base surface in contact with the electrode plate of the flexible synthetic resin thin sheet. It is known that a ribbed separator having ribs provided in the vertical direction of the base surface is used. The ribs do not come into direct contact with the positive electrode plate and the base surface in order to prevent a short circuit due to oxidation of the base surface and opening of holes due to the strong oxidizing power of oxygen gas generated from the positive electrode plate when the lead storage battery is used. Is provided on the surface that comes into contact with the positive electrode plate. The rib also functions as a discharge path for oxygen gas and hydrogen gas (hereinafter referred to as gas) remarkably generated from the electrode plate at the end of charging (for example, Patent Documents 1 and 4).

In recent years, automobiles (hereinafter referred to as ISS vehicles) that have introduced an idling stop system have become widespread for the purpose of improving fuel efficiency and reducing exhaust gas. The lead-acid battery for ISS vehicles has a larger load during use than the conventional lead-acid battery for SLI (starting / lighting / ignition). For example, lead-acid batteries for ISS vehicles are in a deep discharge state because they repeatedly discharge a large current that starts the engine each time they start, and also supply power to drive equipment such as air conditioners, car navigation systems, and car stereos even when the engine is stopped. Will be. In addition, since the engine stops each time the vehicle is stopped, the chances of power generation by the alternator are reduced. In particular, when traveling in an urban area where the continuous mileage is short, shallow charging is repeated as compared with discharging, so that the lead-acid battery for an ISS vehicle is not sufficiently charged and becomes partially charged. When a lead-acid battery is used in a partially charged state, high-concentration sulfuric acid is generated from the electrode plate and precipitates, but the electrolytic solution cannot be expected to be agitated by the gas generated at the end of charging, and stratification occurs and the life tends to be short. .. Therefore, lead-acid batteries for ISS vehicles are required to have stratification measures.

As described above, stratification means that high-concentration sulfuric acid generated from the electrode plate during charging settles toward the bottom of the battery cell, and the sulfuric acid concentration of the electrolytic solution is high in the lower part of the battery cell and low in the upper part. It is a phenomenon that follows. The stratification is measured, for example, as a difference in the vertical specific gravity of the electrolytic solution. When the stratification occurs, sulfation in which passivated lead sulfate accumulates progresses in the lower part of the electrode plate, and the charging efficiency decreases. In addition, a concentration cell is formed and self-discharge progresses rapidly, so that the lead-acid battery has a short life.

For this reason, the applicants, etc., as disclosed in Patent Document 2, propose an improved lead-acid battery that can maintain a high charge state by combining a capacitor electrode material with the negative electrode plate of the lead-acid battery to improve charge acceptability. is doing. By increasing the charge acceptability of the lead-acid battery as described above, even when the lead-acid battery is mounted on an ISS vehicle, the state of charge reaches the end of charging, so that gas can be sufficiently generated.

When a lead-acid battery using the separator described in Patent Document 1 is applied to an ISS vehicle, a large amount of highly concentrated sulfuric acid generated from the electrode plate during charging settles through the gaps between ribs provided in the vertical direction. Therefore, even if gas is generated at the end of charging, the electrolytic solution is not sufficiently agitated, and there is a problem that stratification is likely to occur.

On the other hand, the applicant of the present invention discloses in Patent Document 3 a ribbed separator as shown in FIG. 5 as a means for preventing stratification of a lead storage battery applied to an ISS vehicle. The ribs provided on the base surface of the synthetic resin thin sheet of the ribbed separator are provided in the horizontal direction in the length direction, and the upper surfaces of both ends of the ribs are located higher than the upper surface of the inner portion. The lower surface of the rib has a central portion in the length direction of the rib at the lowest position, and is formed with an upward slope from the central portion toward both ends.

According to this shape, in a lead-acid battery including a group of electrode plates in which a positive electrode plate and a negative electrode plate are laminated via the ribbed separator, high-concentration sulfuric acid generated from the electrode plate during charging is captured on the upper surface of the rib. , Stratification is suppressed. Further, in the case of the ribbed separator of Patent Document 3, even when used in combination with a lead storage battery having high charge acceptability as in Patent Document 2, the gas generated during charging rises along the lower surface of the rib, and the said. It comes out from the end of the rib above the electrode plate. When the gas stays between the electrode plate and the electrolytic solution, the contact area between the active material and the electrolytic solution decreases, and at the time of charging / discharging, a place where the current density locally increases occurs, and the electrode plate deteriorates. Invites and contributes to a short life. Therefore, it is important to secure the gas discharge route.

Japanese Unexamined Patent Publication No. 9-97601 Japanese Patent No. 5576660 Japanese Unexamined Patent Publication No. 2005-197145

However, the ribbed separator disclosed in Patent Document 3 has room for improvement in both prevention of sedimentation of high-concentration sulfuric acid and prevention of gas retention.

Therefore, the present invention provides a ribbed separator for a lead storage battery, which can suppress stratification by both preventing sedimentation of high-concentration sulfuric acid generated from the plates during charging and preventing gas from staying between the plates, and a separator thereof. It is an object of the present invention to provide a highly durable lead-acid battery used.

The ribbed separator according to claim 1 of the present invention is a ribbed separator in which ribs perpendicular to the thickness direction are provided on the base surface of the sheet, and the ribs are horizontal ribs, V-shaped ribs, and right diagonal ribs. The horizontal rib is provided at the lower end in the vertical direction when the ribbed separator is viewed in a plan view, and the V-shaped rib has an angle of π / 6 rad on the right side with respect to the horizontal rib. To π / 3rad, and the angle of the left side is in the range of 2π / 3rad to 5π / 6rad, and the height from the apex formed by the right side and the left side to the respective ends of the right side and the left side. The ratio is in the range of 0.95 to 1.05, and is provided so as to be convex downward on the base surface, and the right diagonal rib starts from the intersection with the horizontal rib. The angle formed by the horizontal rib is in the range of π / 6 rad to π / 3 rad, and is provided so as to extend diagonally upward to the right, and the starting point is located on the right side of the apex. The left diagonal rib has an angle formed with the horizontal rib in the range of 2π / 3rad to 5π / 6rad, starting from the intersection with the horizontal rib, and is provided so as to extend diagonally upward to the left. The starting point is located on the left side of the apex, and the V-shaped rib, the right diagonal rib, and the left diagonal rib are each provided with a plurality of strips on the base surface, and the V-shaped ribs adjacent to each other. The vertical distance between the ends of the right diagonal rib, the left diagonal rib, and the horizontal rib is provided in the range of 8 mm to 15 mm. Each rib has a rectangular shape having an upper surface and a lower surface continuous with the base surface and a top surface continuous with the upper surface and the lower surface in a cross section in the lateral direction, and the ribbed separator is provided. When the positive electrode plate and the negative electrode plate are alternately laminated to form a group of electrode plates, they come into contact with the surface of the opposing electrode plates or another ribbed separator at the top surface. Here, when the cross section of the rib is a non-rectangular polygon, when the electrode plate group is formed, the surface of the electrode plate facing the ribbed separator or the surface in contact with another ribbed separator is topped. Defined as a face.

Since the angle of the right side of the V-shaped rib is steep when it exceeds π / 3rad, the V-shaped shape becomes a vertically long shape, and the high-concentration sulfuric acid generated at the top of the electrode plate reaches the bottom of the battery case cell. The effect of suppressing sedimentation is reduced. If it is less than π / 6rad, the slope is gentle and it is difficult to exhaust the generated gas. Similarly, if the angle of the left side of the V-shaped rib is less than 2π / 3rad, the inclination is steep, so that the V-shaped shape becomes a vertically long shape, and the high-concentration sulfuric acid generated in the upper part of the electrode plate is the battery cell. The effect of suppressing sedimentation to the inner bottom is reduced. If it exceeds 5π / 6rad, the slope is gentle, so it is difficult to exhaust the generated gas. Therefore, it is preferable that the angles of the right side and the left side of the V-shaped rib are formed in the range of π / 6rad to π / 3rad and the range of 2π / 3rad to 5π / 6rad.

For the same reason, the angle formed by the right diagonal rib and the left diagonal rib with the horizontal rib is formed in the range of π / 6rad to π / 3rad and the range of 2π / 3rad to 5π / 6rad, respectively. Is preferable.

Further, the horizontal ribs are provided with the right diagonal ribs and the left diagonal ribs to form pockets below the V-shaped ribs, and high-concentration sulfuric acid generated from the electrode plate during charging is applied to the ribs forming the pockets. It can be captured on the upper surface and suppresses the stratification of the electrolytic solution.

In the above configuration, the V-shaped rib, the right diagonal rib, and the left diagonal rib are each provided in a plurality of rows on the base surface, so that a region for capturing high-concentration sulfuric acid generated from the electrode plate during charging is in the vertical direction. It is dispersed in the water and the sedimentation of high-concentration sulfuric acid is suppressed. Since the high-concentration sulfuric acid dispersed and captured in the vertical direction is relatively small, it easily diffuses into the surrounding electrolytic solution, and it is possible to suppress the deviation of the specific gravity of the upper and lower electrolytic solutions in the battery cell.

In the above configuration, the V-shaped rib provided with a plurality of rows has a height ratio of 0.95 to 1.05 from the apex formed by the right side and the left side to the respective ends of the right side and the left side. If this is the case, since the heights of the left and right ends of the same rib are substantially the same, it is possible to prevent the high-concentration sulfuric acid generated from the electrode plate from overflowing and settling from the low-height end side during charging. Further, as long as the height ratio is in the range of 0.95 to 1.05, the respective vertices may be located on the same straight line on the base surface, or may not be located on the same straight line. It may be located sparsely to the left and right.

Further, in the above configuration, if the vertical distance between the ends of the V-shaped rib, the right diagonal rib, the left diagonal rib, and the horizontal rib adjacent to each other is less than 8 mm, the distance is too narrow. It is difficult to exhaust the generated gas. If it exceeds 15 mm, the interval is too wide and the region for capturing high-concentration sulfuric acid becomes wide, and the effect of suppressing the stratification of the electrolytic solution becomes small. Therefore, the vertical spacing between the ends of the V-shaped ribs, the right diagonal ribs, the left diagonal ribs, and the horizontal ribs adjacent to each other is preferably formed in the range of 8 mm to 15 mm. ..

The ribbed separator according to claim 2 of the present invention is characterized in that, in the above configuration, the V-shaped rib is provided line-symmetrically with a center line orthogonal to the horizontal rib as an axis of symmetry. By making the V-shaped rib line-symmetrical, the heights of the left and right ends of the same rib are the same, so that the high-concentration sulfuric acid generated from the electrode plate during charging overflows from the low-height end side. Since it prevents the gas from settling and the gas can be exhausted evenly from the left and right, it is advantageous in preventing the gas from staying between the plates.

In the ribbed separator according to claim 3 of the present invention, in the above configuration, among the plurality of V-shaped ribs provided, the apex of the V-shaped rib located at the lowest stage has an intersection with the horizontal rib. It is characterized by being provided. By joining the apex of the V-shaped rib located at the lowest stage and the horizontal rib at an intersection, the apex of the V-shaped rib located at the lowest stage when a predetermined group pressure is applied to the electrode plate group. Supports the horizontal ribs and can suppress tearing of the base surface due to bending of the horizontal ribs.

The ribbed separator according to claim 4 of the present invention is characterized in that, in the above configuration, the right diagonal rib and the left diagonal rib are provided in line symmetry with the center line as the axis of symmetry. By providing the right diagonal rib and the left diagonal rib line-symmetrically, the heights of the left and right ends of the left and right diagonal ribs are the same for the same reason as when the V-shaped rib is provided line-symmetrically. This prevents high-concentration sulfuric acid generated from the plates during charging from overflowing from the low end side and settling, and also prevents gas from staying between the plates because gas can be evenly exhausted from the left and right. It works to your advantage.

The lead-acid battery according to claim 5 of the present invention is characterized in that the ribbed separator according to any one of claims 1 to 4 is used. By using the ribbed separator according to any one of claims 1 to 4 in a lead storage battery, it is possible to provide a lead storage battery with high durability.

The lead-acid battery according to claim 6 of the present invention is the lead-acid battery according to claim 5, wherein the group pressure applied to the electrode plate group is in the range of 5 kPa to 30 kPa. If the group pressure applied to the plate group is less than 5 kPa, the pressing force is too weak, and a gap may be formed between the rib and the plate, and high-concentration sulfuric acid may flow out from the gap. On the other hand, if it exceeds 30 kPa, the electrode plate group may not be accommodated in the battery cell, or the battery may swell and be damaged after being accommodated. By setting the group pressure applied to the electrode plate group in the range of 5 kPa to 30 kPa, a gap is unlikely to occur between the rib and the electrode plate, and high-concentration sulfuric acid is satisfactorily captured on the upper surface of the rib. Further, the electrode plates can be housed in the battery cell without damaging the electrode plates. Therefore, it is desirable that the group pressure applied to the electrode plate group is in the range of 5 kPa to 30 kPa.

The ribbed separator of the present invention can capture high-concentration sulfuric acid generated from the electrode plate during charging on the upper surface of the V-shaped rib. Further, the horizontal ribs are provided with the right diagonal ribs and the left diagonal ribs to form pockets below the V-shaped ribs, and high-concentration sulfuric acid generated from the electrode plate during charging is applied to the ribs forming the pockets. Can be captured on the top surface. Therefore, the highly concentrated sulfuric acid generated from the electrode plate during charging is captured by the horizontal ribs, the V-shaped ribs, the right diagonal ribs, and the left diagonal ribs so as not to settle on the inner bottom of the battery case, and the electrolytic solution is stratified. It can suppress the change.

Further, the gas generated from the electrode plate during charging rises along the lower surfaces of the V-shaped rib, the right diagonal rib, and the left diagonal rib, and the ends of the V-shaped rib, the right diagonal rib, and the left diagonal rib. It comes out from the part above the electrode plate. Therefore, it is advantageous in preventing gas retention between the plates.

Further, by setting the group pressure applied to the electrode plate group in which the positive electrode plate and the negative electrode plate are alternately laminated by interposing the ribbed separator of the present invention in the range of 5 kPa to 30 kPa, the pressure between the rib and the electrode plate is set. Gap is unlikely to occur, and high-concentration sulfuric acid is well trapped on the upper surface of the rib. Further, the electrode plates can be housed in the battery cell without damaging the electrode plates.

As described above, according to the present invention, a ribbed separator for a lead storage battery capable of suppressing stratification by both preventing sedimentation of high-concentration sulfuric acid generated from the plates during charging and preventing gas from staying between the plates. And a lead storage battery having high durability using the separator thereof can be provided.

It is a front view which shows the embodiment of the separator with a rib of this invention. It is explanatory drawing which shows the process which made the ribbed separator of this invention into a bag shape, and accommodates the electrode plate. It is a developed view which shows the rib arrangement pattern in embodiment of the separator with a rib of this invention. It is a front view which shows the separator with the rib of the comparative example 1 of this invention. It is a front view which shows the separator with the rib of the comparative example 2 of this invention.

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

FIG. 1 is a front view showing an embodiment of the ribbed separator 1 of the present invention. The ribbed separator 1 is processed into a bag shape so as to house the negative electrode plate 7, and ribs perpendicular to the thickness direction are formed on the base surface 2 of the outer sheet that comes into contact with the positive electrode plate (not shown). It is a flat surface that is provided and has no ribs on the base surface 2 of the inner sheet. The rib includes a horizontal rib 3a, a V-shaped rib 3b, a right diagonal rib 3c, and a left diagonal rib 3d. In the horizontal rib 3a, the positive electrode plate and the negative electrode plate 7 are alternately laminated via the ribbed separator 1, and when this is viewed in a plan view in the stacking direction, the positive electrode current collecting ear side and the negative electrode current collecting ear side face up. It is provided at the lower end in the vertical direction. The V-shaped rib 3b has a right side angle of π / 6rad to π / 3rad and a left side angle of 2π / 3rad to 5π / 6rad with respect to the horizontal rib 3a. The ratio of the heights from the apex 4 formed by the above to the right side, the end right 5R of each of the left sides, and the end left 5L is in the range of 0.95 to 1.05, and is on the base surface 2. It is provided so as to be convex downward. The right diagonal rib 3c has an intersection with the horizontal rib 3a as the starting point right 6R, and the angle formed with the horizontal rib 3a is in the range of π / 6rad to π / 3rad, and is provided so as to extend diagonally upward to the right. The right 6R of the starting point is located on the right side of the apex 4. The left diagonal rib 3d has an intersection with the horizontal rib 3a as a starting point left 6L, an angle formed with the horizontal rib 3a is in the range of 2π / 3rad to 5π / 6rad, and is provided so as to extend diagonally upward to the left. The left 6L of the starting point is located on the left side of the apex 4. A plurality of V-shaped ribs 3b, right diagonal ribs 3c, and left diagonal ribs 3d are provided on the base surface 2 respectively. The vertical spacing Dv between the respective ends of the V-shaped ribs 3b, the right diagonal ribs 3c, the left diagonal ribs 3d, and the horizontal ribs 3a adjacent to each other is provided in the range of 8 mm to 15 mm.

By using the ribbed separator 1 according to the embodiment of the present invention having the above configuration for a lead storage battery, highly concentrated sulfuric acid generated from the positive electrode plate during charging can be captured by the upper surface 3t of the V-shaped rib 3b. Further, the horizontal rib 3a is provided with a right diagonal rib 3c and a left diagonal rib 3d to form a pocket below the V-shaped rib 3b, and high-concentration sulfuric acid generated from the positive electrode plate during charging is applied to the rib forming the pocket. It can be captured on the upper surface 3t. Therefore, the high-concentration sulfuric acid generated from the positive electrode plate during charging is captured by the horizontal ribs 3a, V-shaped ribs 3b, right diagonal ribs 3c, and left diagonal ribs 3d so as not to settle on the inner bottom of the battery case cell, and the electrolytic solution is stratified. It can suppress the change.

Further, by using the ribbed separator 1 according to the embodiment of the present invention having the above configuration in the lead storage battery, the gas generated from the positive electrode plate during charging is the lower surface of the V-shaped rib 3b, the right diagonal rib 3c, and the left diagonal rib 3d. It rises along 3u and exits above the positive electrode plate from the ends of the V-shaped rib 3b, the right diagonal rib 3c, and the left diagonal rib 3d. Therefore, it is advantageous in preventing gas retention between the plates.

In the embodiment shown in FIG. 1, since the angle of the right side of the V-shaped rib 3b has a steep inclination when it exceeds π / 3rad, the V-shaped shape becomes a vertically long shape, and the concentration generated in the upper part of the positive electrode plate is high. The effect of suppressing the sedimentation of sulfuric acid to the inner bottom of the battery case is reduced. If it is less than π / 6rad, the slope is gentle and it is difficult to exhaust the generated gas. Similarly, if the angle of the left side of the V-shaped rib 3b is less than 2π / 3rad, the inclination is steep, so that the V-shaped shape becomes a vertically long shape, and the high-concentration sulfuric acid generated in the upper part of the positive electrode plate is the battery cell. The effect of suppressing sedimentation to the inner bottom is reduced. If it exceeds 5π / 6rad, the slope is gentle, so it is difficult to exhaust the generated gas. Therefore, it is preferable that the angles of the right side and the left side of the V-shaped rib 3b are formed in the range of π / 6rad to π / 3rad and the range of 2π / 3rad to 5π / 6rad.

For the same reason, the angles formed by the right diagonal rib 3c and the left diagonal rib 3d with the horizontal rib 3a are in the range of π / 6rad to π / 3rad and the range of 2π / 3rad to 5π / 6rad, respectively. It is preferably formed by.

Further, the horizontal rib 3a is provided with a right diagonal rib 3c and a left diagonal rib 3d to form a pocket below the V-shaped rib 3b, and high-concentration sulfuric acid generated from the positive electrode plate during charging is applied to the rib forming the pocket. It can be captured on the upper surface 3t and suppresses the stratification of the electrolytic solution.

Further, in the embodiment shown in FIG. 1, a plurality of V-shaped ribs 3b, right diagonal ribs 3c, and left diagonal ribs 3d are provided on the base surface 2 respectively. By providing a plurality of ribs in this way and dispersing the region for capturing the high-concentration sulfuric acid generated from the positive electrode plate in the vertical direction during charging, the sedimentation of the high-concentration sulfuric acid is suppressed. Since the high-concentration sulfuric acid dispersed and captured in the vertical direction is relatively small, it easily diffuses into the surrounding electrolytic solution, and it is possible to suppress the deviation of the specific gravity of the upper and lower electrolytic solutions in the battery cell.

Further, in the embodiment shown in FIG. 1, the V-shaped ribs 3b provided with a plurality of strips have a height ratio of 0 from the apex 4 formed by the right side and the left side to the respective end right 5R and end left 5L. In the range of .95 to 1.05, the heights of the left and right ends of the same rib are substantially the same, so that the high-concentration sulfuric acid generated from the positive electrode plate during charging starts from the low-height end side. It is possible to prevent it from overflowing and settling. Further, as long as the height ratio is in the range of 0.95 to 1.05, the respective vertices 4 may be located on the same straight line on the base surface 2 as shown in FIG. , It may be located sparsely to the left and right instead of being located on the same straight line.

Further, in the embodiment shown in FIG. 1, the vertical distance Dv between the ends of the V-shaped ribs 3b, the right diagonal ribs 3c, the left diagonal ribs 3d, and the horizontal ribs 3a adjacent to each other is less than 8 mm. It is difficult to exhaust the generated gas because the interval Dv is too narrow. If it exceeds 15 mm, the interval Dv is too wide and the region for capturing high-concentration sulfuric acid becomes wide, and the effect of suppressing the stratification of the electrolytic solution becomes small. Therefore, the vertical spacing Dv between the respective ends of the V-shaped ribs 3b, the right diagonal ribs 3c, the left diagonal ribs 3d, and the horizontal ribs 3a adjacent to each other may be formed in the range of 8 mm to 15 mm. preferable.

Further, in the embodiment shown in FIG. 1, the V-shaped rib 3b is provided line-symmetrically with the center line 8 orthogonal to the horizontal rib 3a as the axis of symmetry. By making the V-shaped rib 3b line-symmetrical in this way, the heights of the left and right ends of the same rib are the same, so that the high-concentration sulfuric acid generated from the positive electrode plate during charging is on the low-height end side. Since it prevents the gas from overflowing and settling, and the gas can be exhausted evenly from the left and right, it is advantageous in preventing gas from staying between the plates.

Further, in the embodiment shown in FIG. 1, the apex 4 of the V-shaped rib 3b located at the lowermost stage is provided so as to have an intersection point 9 with the horizontal rib 3a. By joining the apex 4 of the V-shaped rib 3b located at the lowest stage and the horizontal rib 3a at the intersection 9 in this way, the V located at the lowest stage when a predetermined group pressure is applied to the electrode plate group. The apex 4 of the character rib 3b supports the horizontal rib 3a, and it is possible to suppress tearing of the base surface 2 due to bending of the horizontal rib 3a.

Further, in the embodiment shown in FIG. 1, the right diagonal rib 3c and the left diagonal rib 3d are provided in line symmetry with the center line 8 as the axis of symmetry. By providing the right diagonal rib 3c and the left diagonal rib 3d line-symmetrically in this way, the heights of the left and right ends of the left and right ribs are increased for the same reason as when the V-shaped rib 3b is provided line-symmetrically. Since it is the same, it prevents high-concentration sulfuric acid generated from the positive electrode plate from overflowing and settling from the low end side during charging, and gas can be evenly exhausted from the left and right, so gas stays between the plates. It works in an advantageous way to prevent.

The lead-acid battery according to the embodiment of the present invention is a lead-acid battery in which a group of electrode plates in which a positive electrode plate and a negative electrode plate 7 are alternately laminated with the ribbed separator 1 interposed therebetween is inserted in an electric tank cell. .. By using the ribbed separator 1 in a lead storage battery, a highly durable lead storage battery can be provided.

Further, in the lead storage battery according to the embodiment of the present invention, the group pressure applied to the electrode plate group is in the range of 5 kPa to 30 kPa. If the group pressure applied to the plate group is less than 5 kPa, the pressing force is too weak, and a gap may be formed between the rib and the plate, and high-concentration sulfuric acid may flow out from the gap. On the other hand, if it exceeds 30 kPa, the electrode plate group may not be accommodated in the battery cell, or the battery may swell and be damaged after being accommodated. Therefore, it is desirable that the group pressure applied to the electrode plate group is in the range of 5 kPa to 30 kPa.

Further, in the embodiment shown in FIG. 1, the horizontal rib 3a, the V-shaped rib 3b, the right diagonal rib 3c, and the left diagonal rib 3d are all continuously provided on the base surface 2 in the longitudinal direction without breaking. ing. If the length of each rib is set so that the end of the rib is located outside the end of the positive electrode plate to which the rib abuts when the electrode plate group is formed, the positive electrode plate is charged. It is more preferable because the high-concentration sulfuric acid generated from the ribs can be captured by the upper surface 3t of the rib without leaking.

Although not shown, in the embodiment of the present invention, the horizontal ribs, the V-shaped ribs, the right diagonal ribs, and the left diagonal ribs all have an upper surface and a lower surface continuous with the base surface, and the upper surface and the upper surface in the cross section in the lateral direction. It has a rectangular shape having a lower surface and a continuous top surface, and when the positive electrode plate and the negative electrode plate are alternately laminated via the ribbed separator to form an electrode plate group, the electrode plates facing each other are formed. It abuts on the surface or other ribbed separators on the top surface. Further, when a soft material is used for the rib, the adhesion to the electrode plate is enhanced, and high-concentration sulfuric acid is better captured on the upper surface of the rib. Further, even if the rib is used as a hollow material and elastically deformed, good adhesion can be obtained. An example is shown in which the cross-sectional shapes of the horizontal rib, the V-shaped rib, the right diagonal rib, and the left diagonal rib are rectangular, but the cross-sectional shape is not limited to the rectangular shape, and any other polygonal shape, circular shape, or any other shape that is in close contact with the electrode plate may be used. Is optional.

FIG. 2 is an explanatory diagram showing a step of forming the ribbed separator 1 of the present invention into a bag shape and accommodating the negative electrode plate 7. As shown in FIG. 2A, the ribbed separator 1 of the present invention is a ribbed sheet-shaped separator 10 cut to a certain size and developed into a rectangular sheet shape, as shown in FIG. 2B, as a negative electrode plate. Fold it in half along the center line 10e so as to wrap around 7, align the lower end of the negative electrode plate 7 with the center line 10e, and overlap one side surface 10a and the other side surface 10b as shown in FIG. 2C. In FIG. 2 (D), both side portions of one side surface 10a and the other side surface 10b that are overlapped with each other are joined by an automatic joining device, and in the present invention, a gear sealing method in which two gears are passed and joined. It is processed into a bag shape as shown.

In the present embodiment, the ribbed separator 1 is processed into a bag shape so as to house the negative electrode plate 7, and ribs perpendicular to the thickness direction are formed on the base surface 2 of the outer sheet so as to abut the positive electrode plate. It is exemplified that the negative electrode plate 7 is housed in a ribbed separator 1 which is a flat surface without ribs on the base surface 2 of the inner sheet, and is alternately laminated with the positive electrode plates to form a group of electrode plates. However, the ribbed separator 1 is not processed into a bag shape, and the two semi-ribbed sheet-shaped separators obtained by cutting the ribbed sheet-shaped separator 10 along the center line 10e are formed on the positive electrode plate on the surface provided with the ribs, respectively. The negative electrode plates may be brought into contact with each other so as to sandwich them, or the negative electrode plates may be alternately laminated so as to sandwich the negative electrode plates on the front and back base surfaces 2 of the sheet-shaped separator with half ribs. The positive electrode plate and the negative electrode plate may be alternately laminated via a ribbed separator in which ribs are provided so that the ribs abut on the positive electrode plate and the negative electrode plate to form a group of electrode plates.

Hereinafter, the present invention will be specifically described with reference to Examples. However, the present invention is not limited to the following examples.

(Example 1)
The ribbed separator 1 of the present invention was manufactured by the following method. First, high-density polyethylene resin powder, inorganic powder (silica powder with an average particle size of 5 μm) and mineral oil (paraffin oil) are mixed with a mixer, and the mixture is extruded into a sheet by a twin-screw extruder. A thin sheet having a thickness of 0.3 mm on the base surface provided with the plurality of ribs was obtained by passing through the molding rolls in which the grooves of the rib arrangement pattern shown in FIG. 3 were engraved on the rolls and performing pressure molding. Then, it was immersed in a solvent to remove a part of the mineral oil to obtain a ribbed sheet separator.

The ribbed sheet separator 10 cut to a certain size and developed into a rectangular sheet is oriented along the center line 10e so as to wrap the negative electrode plate 7 with the surface on which the ribs are formed facing outward as shown in FIG. After folding in half, one side surface 10a and the other side surface 10b are overlapped, and the overlapped one side surface 10a and the other side surface 10b are joined to each other by a gear seal method to form a bag. A bag-shaped ribbed separator 1 was obtained. In this step, if necessary, ribless regions may be provided at the left and right ends of the ribbed sheet-shaped separator 10 as a binding allowance for applying the gear sealing method.

In the rib arrangement pattern shown in FIG. 1, the cross-sectional shapes of the horizontal rib 3a, the V-shaped rib 3b, the right diagonal rib 3c, and the left diagonal rib 3d are all rectangular with a width of 0.4 mm and a height of 0.5 mm. The V-shaped rib 3b has an angle of the right side in the range of π / 4rad and an angle of the left side in the range of 3π / 4rad. The center line 8 having a height ratio of 1.00 was set as the axis of symmetry, and the apex 4 of the V-shaped rib 3b located at the lowest stage and the horizontal rib 3a were joined at an intersection point 9. The vertical distance Dv between the ends of the V-shaped ribs 3b, the right diagonal ribs 3c, the left diagonal ribs 3d, and the horizontal ribs 3a adjacent to each other was set to 10 mm. Further, the horizontal spacing Dh of the V-shaped ribs 3b adjacent to each other was set to 10 mm. Further, the right diagonal rib 3c and the left diagonal rib 3d have line symmetry with the center line 8 having an angle formed by the horizontal rib 3a in the range of π / 4rad and 3π / 4rad, respectively.

A lead-acid battery using the bag-shaped ribbed separator 1 was manufactured by the following procedure. An unchemical positive electrode filling plate and a negative electrode filling plate manufactured by a known method are alternately laminated with a positive electrode filling plate in a state where the negative electrode filling plate is housed in the bag-shaped ribbed separator 1 to form a group of electrode plates. After assembling, the group pressure applied to the electrode plate group is accommodated in the battery cell at 20 kPa, and an electrolytic solution having a specific gravity of 1.280 and a liquid temperature of 20 ° C. is injected into the battery to form a battery according to a conventional method. A D23 type liquid lead-acid battery of Example 1 having an hourly rate capacity of 50 Ah was manufactured.

(Comparative Example 1)
As shown in FIG. 4, a rib arrangement in which the horizontal distance Dh between the ends of the vertical ribs 11 provided in the vertical direction is 10 mm and the mixture is composed of only a plurality of vertical ribs 11. A bag-shaped ribbed separator 1 was produced by the same method as in Example 1 except that the pattern was pressure-molded by passing between the engraved molding rolls, and the liquid lead-acid battery of Comparative Example 1 was manufactured. did.

(Comparative Example 2)
As shown in FIG. 5, the vertical distance Dv between the ends of the V-shaped ribs 3b is 10 mm, which is the same as in Example 1, and the angle of the right side of the V-shaped ribs 3b is π / 36rad. Passing between the forming rolls engraved in a rib arrangement pattern composed of only a plurality of V-shaped ribs 3b that are axisymmetric with the center line 8 as the axis of symmetry, with the angle of the left side in the range of 35π / 36rad. A bag-shaped ribbed separator 1 was produced by the same method as in Example 1 except that the liquid lead-acid battery of Comparative Example 2 was produced.

The charge / discharge tests of the liquid lead-acid batteries of Example 1, Comparative Example 1 and Comparative Example 2 were repeatedly carried out according to the following procedure to confirm the presence or absence of stratification. After repeating the cycle of discharging 50% of the 5-hour rate capacity with a current amount equivalent to 0.2C from a fully charged state and then charging 105% of the discharged electricity amount with a current amount equivalent to 0.1C three times. The cells were allowed to stand at room temperature for 16 hours or more, the specific densities of the upper and lower electrolytic solutions in each cell of the electric tank were measured, and stratification was evaluated from the difference in the upper and lower specific densities of the electrolytic solutions. At this time, it was judged that stratification occurred when the difference in the vertical density was 0.005 or more. In addition, during the test, the state of the gas that escaped from the electrode plate group in the battery case cell into the electrolytic solution was observed, and the gas release property was evaluated. At this time, the gas release property of Comparative Example 1 in which the vertical ribs were provided on the base surface of the separator in the vertical direction was set to 100%, and the gas release properties of Example 1 and Comparative Example 2 were evaluated.

(Results of Examples and Comparative Examples)
For Example 1, Comparative Example 1, and Comparative Example 2, Table 1 shows the measurement results of the vertical specific gravity of the electrolytic solution after the above test and the evaluation results of the gas release property. The average values of all 6 cells are shown for the upper electrolyte specific density and the lower electrolyte specific density.

As is clear from Table 1, in the lead-acid battery of Example 1, the difference in the vertical specific gravity of the electrolytic solution after the test was 0.002, and stratification was suppressed. The first reason for this is that the high-concentration sulfuric acid generated from the positive electrode plate during charging is captured by the upper surfaces of the horizontal ribs, V-shaped ribs, right diagonal ribs, and left diagonal ribs provided on the base surface of the separator. It is probable that this prevented the sedimentation to the inner bottom of the battery case. The second reason is the range of angles of the right side and the left side of the V-shaped rib, the range of the angle formed by the right diagonal rib and the horizontal rib of the left diagonal rib, and the V-shaped ribs adjacent to each other. By setting the vertical spacing between the ends of the right diagonal rib, the left diagonal rib, and the horizontal rib to a suitable range, the gas generated at the end of charging is the V-shaped rib, the right diagonal rib, and the right diagonal rib. And, as it rises along the lower surface of the left diagonal rib and gas escapes from the end of the rib above the positive electrode plate, gas retention between the plates is prevented and the electrolytic solution is well agitated. It is presumed that it was done.

In Comparative Example 1, since the vertical ribs are provided on the base surface of the separator in the vertical direction, a large amount of highly concentrated sulfuric acid generated from the positive electrode plate during charging settles through the gaps between the vertical ribs. It is presumed that even if the gas generated at the end of charging is well released, the electrolytic solution is not sufficiently stirred and stratification occurs, resulting in a difference in the vertical specific gravity.

On the other hand, in Comparative Example 2, since the gently inclined V-shaped rib is provided, highly concentrated sulfuric acid generated from the positive electrode plate during charging is captured by the upper surface of the V-shaped rib and settles to the inner bottom of the battery case cell. Although it is suppressed, it is difficult to exhaust the generated gas, and the electrolytic solution cannot be agitated. In addition, since the horizontal ribs are not provided, the high-concentration sulfuric acid generated from the lower part of the positive electrode plate during charging is not captured at the lower part of the base surface of the separator and settles at the inner bottom part of the battery case, so that some stratification occurs. , It is presumed that there was a difference in the vertical specific gravity.

As described above, the ribbed separator of the present invention can capture high-concentration sulfuric acid generated from the positive electrode plate during charging on the upper surfaces of the V-shaped rib, the right diagonal rib, and the left diagonal rib. Further, the horizontal rib is provided with the right diagonal rib and the left diagonal rib to form a pocket below the V-shaped rib, and high-concentration sulfuric acid generated from the positive electrode plate during charging is applied to the upper surface of the rib forming the pocket. Can be captured with. Therefore, the high-concentration sulfuric acid generated from the positive electrode plate during charging is captured by the horizontal ribs, the V-shaped ribs, the right diagonal ribs, and the left diagonal ribs so as not to settle on the inner bottom of the battery case, and the electrolytic solution is stratified. It can suppress the change.

The angles of the right side and the left side of the V-shaped rib are in the range of π / 6rad to π / 3rad, the range of 2π / 3rad to 5π / 6rad, the right diagonal rib, and the horizontal rib of the left diagonal rib. The angles formed by each are in the range of π / 6rad to π / 3rad and 2π / 3rad to 5π / 6rad, the V-shaped ribs adjacent to each other, the right diagonal ribs, the left diagonal ribs, and the horizontal ribs. Since the vertical spacing between the respective ends is formed in the range of 8 mm to 15 mm, the gas generated during charging and discharging is along the lower surface of the V-shaped rib, the right diagonal rib, and the left diagonal rib. It rises and escapes from the end of the rib to the upper part of the positive electrode plate, which is advantageous in preventing gas retention between the electrode plates.

Further, by setting the group pressure applied to the electrode plate group in which the positive electrode plate and the negative electrode plate are alternately laminated with the ribbed separator of the present invention interposed therebetween in the range of 5 kPa to 30 kPa, the space between the rib and the electrode plate is set. Sulfuric acid with a high concentration is well trapped on the upper surface of the rib. Further, the electrode plates can be housed in the battery cell without damaging the electrode plates.

As described above, according to the present invention, a ribbed separator for a lead storage battery capable of suppressing stratification by both preventing sedimentation of high-concentration sulfuric acid generated from the plates during charging and preventing gas from staying between the plates. And a lead storage battery having high durability using the separator thereof can be provided.

1 Separator with ribs 2 Base surface 3a Horizontal ribs 3b V-shaped ribs 3c Right diagonal ribs 3d Left diagonal ribs 3t Top surface 3u Bottom surface 4 Vertices 5R End part right 5L End part left 6R Start point right 6L Start point left 7 pole plate 8 Center line 9 Intersection 10 Sheet-shaped separator with ribs 10a, 10b Side surfaces 10c, 10d Both sides 10e Center line 11 Vertical ribs

Claims (6)

In a ribbed separator having ribs perpendicular to the thickness direction on the base surface of the sheet.
The ribs include horizontal ribs, V-shaped ribs, diagonal right ribs, and diagonal left ribs.
The horizontal rib is provided at the lower end in the vertical direction when the ribbed separator is viewed in a plan view.
The V-shaped rib has an angle of the right side from π / 6rad to π / 3rad and an angle of the left side of 2π / 3rad to 5π / 6rad with respect to the horizontal rib, and the right side and the left side. The ratio of the heights from the apex formed by the above to the ends of the right side and the left side is in the range of 0.95 to 1.05, and is provided so as to be convex downward on the base surface. And
The right diagonal rib starts at an intersection with the horizontal rib, and the angle formed by the horizontal rib ranges from π / 6 rad to π / 3 rad, and is provided so as to extend diagonally upward to the right. The starting point is located on the right side of the apex.
The left diagonal rib starts at an intersection with the horizontal rib and has an angle formed by the horizontal rib in the range of 2π / 3rad to 5π / 6rad, and is provided so as to extend diagonally upward to the left. The starting point is located on the left side of the apex.
A plurality of the V-shaped ribs, the right diagonal ribs, and the left diagonal ribs are provided on the base surface, respectively, and of the V-shaped ribs, the right diagonal ribs, the left diagonal ribs, and the horizontal ribs adjacent to each other. A ribbed separator for a lead-acid battery, characterized in that the vertical spacing between the ends is in the range of 8 mm to 15 mm. The separator with a rib for a lead storage battery according to claim 1, wherein the V-shaped rib is provided in line symmetry with a center line orthogonal to the horizontal rib as an axis of symmetry. One of claims 1 or 2, wherein the apex of the V-shaped rib located at the bottom of the plurality of V-shaped ribs is provided so as to have an intersection with the horizontal rib. Ribbed separator for lead-acid batteries as described in section. The lead-acid battery according to any one of claims 1 to 3, wherein the right diagonal rib and the left diagonal rib are provided so as to have line symmetry with the center line as an axis of symmetry. Ribbed separator. A lead-acid battery according to any one of claims 1 to 4, wherein the ribbed separator for the lead-acid battery is used. The lead-acid battery according to claim 5, wherein the group pressure applied to the electrode plate group is in the range of 5 kPa to 30 kPa.

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