JP2017033864A - Control valve type lead-acid battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a control valve type lead-acid battery which has high capacity and improves a high-rate discharge performance.SOLUTION: A control valve type lead-acid battery 1 is manufactured. The control valve type lead-acid battery comprises an electrode plate group which is configured by laminating a cathode plate 2 and an anode plate 3 via a retainer 4, and an electrolyte. The retainer 4 includes one surface 4a which is abutted with the anode plate 3 in a direction of lamination, and another surface 4b which is abutted with the cathode plate 2 in the direction of lamination. An active material mass ratio (N/P) of a total mass N of anode active materials in the anode plate 3 and a total mass P of cathode active materials in the cathode plate 2 under a full charge state is adjusted within a range of 0.7 to 1.1. The retainer 4 contains first glass fibers having a number average fiber diameter equal to or less than 1.0 μm and second glass fibers having a number average fiber diameter equal to or more than 3.0 μm. A velocity ratio (A/B) of a suction velocity A of the electrolyte on the one surface 4a of the retainer 4 and a suction velocity B of the electrolyte on the other surface 4b is adjusted within a range of 1.3 to 1.4.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a control valve type lead storage battery.

  Control valve-type lead-acid batteries are relatively inexpensive, reliable and maintenance-free, and are widely used in various fields such as uninterruptible power supplies and power storage applications.

  The electrolytic solution of the control valve type lead-acid battery is usually kept in a separator called a retainer. Since the retainer touches both the positive electrode plate and the negative electrode plate, the influence of the retainer characteristics on the battery characteristics is large. The ideal retainer has (1) good diffusion of electrolyte in the thickness and width direction in the electrode group, and (2) low diffusion of electrolyte in the direction from the ear to the foot of the electrode plate. (3) Good follow-up to the expansion and contraction of the active material that occurs during charging and discharging, (4) Osmotic short-circuit is not likely to occur when left in an overdischarged state, (5) It is various such as easy movement of gas generated during charging, so far, change of retainer density in the thickness direction (Patent Document 1), inorganic substance (Patent Document 2) and organic substance (Patent Document 3) into the retainer. Has been added.

Japanese Patent Laid-Open No. 08-203490 Japanese Patent No. 3054254 Japanese Patent Application Laid-Open No. 11-307074

  However, although the retainers described in Patent Documents 1, 2, and 3 seem to have a wide effect as retainers, they do not hold for all battery configurations. Particularly, when the mass ratio of the positive electrode and the negative electrode changes, the high rate discharge performance changes greatly.

  The present invention has been made in view of the above problems, and it is an object of the present invention to provide a control valve type lead-acid battery having a high capacity and excellent discharge performance.

  The control valve-type lead-acid battery according to the present invention includes an electrode plate group in which a negative electrode plate and a positive electrode plate are stacked via a retainer, and an electrolyte, and the retainer is in contact with the negative electrode and one surface in the stacking direction and the positive electrode A plate and the other surface in contact with the stacking direction. In the control valve type lead storage battery of the present invention, in the fully charged state, the relationship between the total mass (N) of the negative electrode active material held on the negative electrode plate and the total mass (P) of the positive electrode active material held on the positive electrode plate is (N / P) is adjusted to a range of 0.7 to 1.1. The retainer used in the control valve type lead storage battery constituted by the positive electrode / negative electrode active material mass ratio is a first glass fiber having a number average fiber diameter of 1.0 μm or less and a first glass fiber having a number average fiber diameter of 3.0 μm or more. It is comprised from 2 types of glass fibers of 2 glass fibers. The number average fiber length of the glass fibers in the retainer composed of these two types of glass fibers is in the range of 200 to 300 μm. The retainer made of these two types of glass fibers has a relative relationship between the electrolyte absorption rate A on one surface that contacts the negative electrode plate and the electrolyte absorption rate B on the other surface that contacts the positive electrode plate. The relationship is adjusted to a range of (A / B) = 1.3 to 1.4.

  Thus, by adjusting the mass ratio of the negative electrode active material and the positive electrode active material, by adjusting the liquid absorption rate ratio of the electrolyte solution on one side and the other side of the retainer containing two types of glass fibers, The capacity of the lead storage battery can be increased, and the discharge performance can be improved. Furthermore, when the ratio (active material mass ratio) N / P of the total mass N of the negative electrode active material and the total mass P of the positive electrode active material is adjusted to a range of 0.9 to 1.1, the discharge characteristics are remarkably improved. be able to.

  In addition, when active material mass ratio N / P is less than 0.7, a discharge characteristic will fall, and when active material mass ratio N / P exceeds 1.1, battery capacity will fall. Moreover, when the number average fiber diameter of the first glass fiber exceeds 1.0 μm, the number average fiber diameter of the second glass fiber is not 3.0 μm, and the number average fiber of the glass fiber in the retainer. The length is out of the range of 200 to 300 μm. When the number average fiber length of the glass fibers in the retainer is less than 200 μm, the density of the retainer increases (the volume of the gap in the retainer decreases), so that the permeability of the electrolytic solution to the retainer decreases, and the retainer in the retainer When the number average fiber length of the glass fibers exceeds 300 μm, the density of the retainer becomes small (the volume of the gap in the retainer becomes large), thereby affecting the absorbability of the electrolytic solution and controlling the liquid absorption speed ratio. I can't. Furthermore, when the liquid absorption speed ratio A / B on both sides of the retainer is less than 1.3, neither the capacity increase of the battery nor the improvement of the discharge characteristics can be achieved. When A / B exceeds 1.4, the battery capacity decreases.

  A retainer capable of obtaining such an effect has a structure in which one surface forms a mesh-like uneven surface and the other surface forms an irregular uneven surface. That is, the retainer composed of two types of glass fibers has two uneven surfaces having different shapes, so that the liquid absorption rate ratio of the electrolyte solution on both surfaces of the retainer can be adjusted. A retainer having such a structure can be manufactured using a wet papermaking machine. Specifically, a papermaking body is produced by supplying a slurry in which two kinds of glass fibers are mixed onto a papermaking net of a wet papermaking machine. In this papermaking body, the surface in contact with the papermaking net becomes a mesh-like uneven surface and constitutes one surface of the separator, and the surface not in contact with the papermaking net becomes an irregular uneven surface and constitutes the other surface of the separator be able to.

  In order to obtain the liquid absorption speed ratio which is the premise for obtaining the above effect, among the two types of glass fibers constituting the separator, the dimension of the first glass fiber is 0.8 μm to the number average fiber diameter. 1.0 μm, and the second glass fiber size is 3.5 μm to 5.0 μm in terms of the number average fiber diameter, and the relationship between the mass M1 of the first glass fiber and the mass M2 of the second glass fiber. Adjustment may be made so that (M1 / M2) = 4 to 2.3.

It is a perspective view which shows the member structure of the control valve type lead acid battery which is embodiment of this invention. It is the photograph which image | photographed the external appearance of the retainer which comprises the control valve type lead acid battery of this invention, (A) shows one surface of a retainer, (B) shows the other surface of a retainer.

  Hereinafter, embodiments of the present invention will be described in detail. FIG. 1 is a perspective view showing a control valve type lead storage battery of this example. In FIG. 1, reference numeral 1 is a control valve type lead-acid battery shown so that the internal configuration can be understood. In this control valve type lead storage battery 1, a positive electrode plate 2 and a negative electrode plate 3 are laminated via a retainer 4 to constitute an electrode plate group.

  The retainer 4 includes one surface 4a that contacts the negative electrode plate 3 in the stacking direction and the other surface 4b that contacts the positive electrode plate 2 in the stacking direction. In the retainer 4, as shown in the photograph of FIG. 2, one surface 4a forms a mesh-like uneven surface, and the other surface 4b forms an irregular uneven surface.

  The electrode plates 2 and 3 having the same polarity constituting this electrode plate group are connected to each other by straps 8 and 9 via ear portions 6 and 7. The electrode plate group is accommodated in the battery case 12 and closed by the lid 13 to assemble a lead storage battery. At this time, the poles 10 and 11 extending from the straps 8 and 9 are connected to the external terminals 14 and 15 protruding from the surface of the lid 13 from the back surface of the lid 13.

  In addition to the external terminals 14 and 15, the lid 13 discharges, out of the battery case 12, excess gas that could not be absorbed by the gas absorption reaction of the negative electrode out of the oxygen gas generated at the positive electrode during charging. A control valve 16 is provided. The material of the control valve 16 is preferably a material excellent in chemical resistance (acid resistance, silicon oil resistance), wear resistance, and heat resistance, specifically, fluororubber.

  Then, a predetermined amount of electrolytic solution (not shown) is injected into the battery case 12 from a liquid injection port (not shown) provided in the lid body 13 to form a battery case, and the control valve type lead-acid battery of this example 1 was produced. The material of the battery case 12 is not particularly limited, and specifically, polypropylene, ABS, modified PPE (polyphenylene ether) or the like can be used.

  In this example, the total mass (N) of the negative electrode active material held on the negative electrode plate 3 and the total mass (P) of the positive electrode active material held on the positive electrode plate 2 in the fully-charged control valve type lead storage battery 1. And the active material mass ratio (N / P) = 0.7 to 1.1, and the retainer 4 used in the control valve type lead storage battery 1 configured with this active material weight ratio is 1.0 μm or less. It is comprised from two types of glass fibers, the glass fiber (1st glass fiber) which is a number average fiber diameter, and the glass fiber which is a number average fiber diameter (2nd glass fiber) of 3.0 micrometers or more. The number average fiber length of the glass fiber in the retainer 4 comprised with this glass fiber is 200-300 micrometers. The retainer 4 made of this glass fiber has a relative relationship between the liquid absorption rate A of the electrolyte 4 on one surface 4 a that contacts the negative electrode plate 3 and the liquid absorption rate B of the other surface 4 b that contacts the positive electrode plate 2. A / B = 1.3 to 1.4.

<Total mass of negative electrode active material and total mass of positive electrode active material>
The control valve type lead-acid battery having the ratio of the total mass of the negative electrode active material and the total mass of the positive electrode active material is the active material paste composition, the active material paste characteristics, the lattice shape, the active material filling amount, The number of positive and negative plates can be adjusted. However, the manufacturing method of the control valve type lead acid battery is not limited to this.

<Glass fiber>
The glass fiber in the present invention preferably has acid resistance such as alkali glass, ECR glass, Advantech glass and the like because dilute sulfuric acid is used for the electrolyte. Of the two types of glass fibers used in this example, the first glass fiber preferably has a number average fiber diameter of 0.8 to 1.0 μm, and the second glass fiber has a number average fiber diameter of 3.5. It is preferable that it is -5.0 micrometers.

  The glass fiber in the retainer composed of two types of glass fibers satisfying such conditions is 200 to 300 μm in terms of the number average fiber length. When the number average fiber length of the glass fibers in the retainer is in the range of 200 to 300 μm, it is easy to obtain a retainer having a relatively uniform pore diameter, and the permeability of the electrolytic solution to the retainer is maintained. In addition, since it does not affect the absorbability of the electrolytic solution, it is relatively easy to control the liquid absorption speed ratio described later. Furthermore, sufficient strength as a retainer (for example, 1 MPa or more in tensile strength) can be maintained. Furthermore, good papermaking properties are easily obtained during papermaking, which will be described later.

  When the number average fiber length of the glass fibers in the retainer is less than 200 μm, it becomes difficult to obtain a retainer having a uniform pore diameter, and the permeability of the electrolytic solution to the retainer decreases. On the other hand, when the number average fiber length of the glass fibers in the retainer exceeds 300 μm, the volume of the gap in the retainer becomes too large (because it affects the absorbability of the electrolyte), and the liquid absorption rate ratio described later is It's hard to control. Moreover, when producing the papermaking body mentioned later, since the dispersibility of a raw material component falls in the slurry used, the papermaking nature at the time of papermaking falls.

  Here, in the present embodiment, the number average fiber diameter and the number average fiber length of the fibers are directly observed by, for example, a dynamic image analysis method, a laser scanning method (for example, conforming to JIS L1081), a scanning electron microscope, or the like. It can ask for. Specifically, the number average fiber diameter and the number average fiber length can be determined by observing about 400 fibers using these methods and taking the average value.

  The glass fiber content in the glass mat is preferably 70 to 99% by mass, where the total mass of the retainer is 100%. By setting the glass fiber content to 70% by mass or more, there is a tendency to obtain both strength and liquid retention sufficient as a retainer. By setting the content to 99% by mass or less, strength, liquid retention, and cycle characteristics are improved. It tends to be compatible.

<Liquid absorption speed>
The liquid absorption rate in the present invention was measured by the method described in the battery industry association standard SBA S 0406. Specifically, five sheets are arbitrarily selected from the paper-made retainers, and test pieces of 30 mm × 150 mm are collected one by one from the longitudinal direction (paper making direction) and the horizontal direction of each retainer. Then, a total of 10 test pieces are dried in air at 60 ° C. or lower, and the moisture content based on weight is made 0.1% or lower. Purified dilute sulfuric acid specified in JIS K 1321 having a specific gravity of 1.300 (20 ° C.) is poured into the container. The temperature of the diluted sulfuric acid to be injected is 15 to 25 ° C. Draw a marked line with a pencil parallel to the short side at a position 10 mm from the end face on the short side of the test piece, hook the short side facing it, hold the test piece vertically, and quickly reach the position of the marked line Immerse in dilute sulfuric acid. After immersion for 3 minutes, use a length meter (length measuring device) to prevent the length meter and the test piece from coming into contact between the surface of the dilute sulfuric acid and the height of the diluted sulfuric acid that has penetrated the test piece. To measure. Here, the height of the dilute sulfuric acid is a position where an imaginary line drawn in the length direction from the center in the short side direction of the test piece intersects with the permeated dilute sulfuric acid. The liquid absorption speed is calculated by dividing the measured dilute sulfuric acid height by the immersion time.

<Reticulated uneven surface and irregular uneven surface>
The mesh-like uneven surface in the present invention is an uneven surface that can be formed on the paper-making mesh side that receives the slurry when the glass fiber slurry is charged into the paper machine in the step of producing a paper-making body, which will be described later. The surface smoothed by the net of the paper machine that receives the fiber. On the other hand, the irregular concavo-convex surface is a concavo-convex surface formed on the side opposite to the mesh-shaped concavo-convex surface, and is a surface not smoothed by the papermaking net of the paper machine.

<Retainer manufacturing method>
There is no restriction | limiting in particular in the manufacturing method of the retainer of this embodiment, For example, wet papermaking, dry papermaking, etc. are mentioned. In the present embodiment, among these, it is preferable to employ a papermaking method based on a wet method (wet papermaking). This production method includes a step of preparing a slurry prepared by mixing glass fiber and, if necessary, a resin or the like with water, a step of papermaking the slurry to prepare a papermaking product, and a papermaking product using a pressure machine In the thickness direction, and a manufacturing method through a step of heat-treating the compression body at a temperature equal to or higher than the softening point of the resin as necessary.

<Process for preparing slurry>
In this step, as the glass fiber, a first glass fiber having a number average fiber diameter of 0.8 to 1.0 μm and a second glass fiber having a number average fiber diameter of 3.5 to 5.0 μm are necessary. Accordingly, a slurry is prepared by dispersing in a predetermined dispersion medium together with resin, pulp and the like. The adjustment of the slurry can be performed by, for example, a mixer, a ball mill, a pulper, or the like. Note that water is generally used as the dispersion medium.

  What is necessary is just to adjust content of each raw material component in a slurry so that content of each raw material component in the retainer obtained may become the range mentioned above. However, from the viewpoint of ensuring good papermaking properties, it is preferable that the raw material component in the slurry is 100% and the glass fiber is 70 to 99% by mass.

  The slurry may contain polymer particles as organic fibers or a binder as necessary. Organic fibers and polymer particles may be used alone or in admixture of two or more. Organic fibers and polymer particles include those sulfonated.

  This slurry may contain a surfactant. By including the surfactant, the raw material components can be easily dispersed when the retainer is manufactured. The surfactant may be decomposed in a subsequent heat treatment. As the surfactant, any of a silane coupling agent, a cationic surfactant, an anionic surfactant, and a nonionic surfactant may be used. The content of the surfactant is preferably 0.01 to 5% by mass with 100% of the raw material components in the slurry.

  The slurry may contain a flocculant. The yield of the retainer manufactured by including a flocculant can be improved. The flocculant may be either a cationic polymer flocculant or an anionic polymer flocculant, and both may be used together. The content of the flocculant is preferably 0.001 to 0.5 mass% with the raw material component in the slurry as 100%.

<Process for producing papermaking-process for compression>
In these steps, the slurry is paper-made using a general paper machine to produce a paper-making body, and then the paper-making body is further compressed in the thickness direction using a pressure machine. In order to obtain a desired thickness and density, the papermaking body is preferably compressed at 1 to 30 MPa for 1 to 5 minutes.

<Step of heat treatment after compression>
Although this step is not necessarily performed, it is performed as necessary in accordance with the material configuration of the retainer. By heat-treating the compression body at a temperature equal to or higher than the softening point of the resin in this step, the resin is softened and the glass fibers are bonded to each other, or the viscosity mineral is reliably attached to the glass fibers. The retainer can be provided with flexibility by coating a part or all of the surface of a viscous mineral or the like with a resin. Further, the resin can be partially decomposed to improve the holding power of the electrolytic solution.

  The treatment temperature is not necessarily limited because it depends on the softening point of the resin, but it is preferably performed at 100 to 200 ° C. By setting the treatment temperature to 100 ° C. or higher, glass fibers, viscous minerals and the like tend to be bound to each other, and by setting the processing temperature to 200 ° C. or lower, the manufacturing process is easily simplified. In addition, you may perform heat processing, pressing suitably according to the constituent material of a retainer, combining with the pressurization process mentioned above.

<Production of control valve type lead acid battery>
The positive electrode active material is lead powder containing lead monoxide as a main component, added with red lead, and mixed with a predetermined amount of water and dilute sulfuric acid. Fill and age and dry under specified conditions. Here, by changing the addition amount of water and dilute sulfuric acid, and aging / drying conditions, the surface area of the active material of the positive electrode plate in the fully charged state can be adjusted within a certain target range after the formation.

  The negative electrode active material is a powder of lead alloy containing lead powder containing lead monoxide as a main component, mixed with an additive, and mixed with a predetermined amount of water and dilute sulfuric acid. Fill and age and dry under specified conditions. Here, the surface area of the active material of the negative electrode plate in a fully charged state can be adjusted within a certain range after chemical conversion by changing the addition amount of the additive, water and dilute sulfuric acid, and the aging / drying conditions.

  Furthermore, it is possible to adjust the surface area of the positive and negative electrode active materials by changing the chemical conversion conditions.

  Further, the amount of the positive and negative electrode active materials can be adjusted by changing the amount of the paste-like active material filled in the lead alloy current collector.

  As the additive added to the paste-like negative electrode active material, an acid-resistant fiber for reinforcement, a lead sulfate crystal growth inhibiting additive, and a shrinkage preventing agent are used. As the acid-resistant fiber for reinforcement, acrylic fiber, polyester fiber, polyethylene terephthalate (PET) fiber or the like can be used, and it is desirable to use PET fiber from the viewpoint of price and acid resistance. By using the acid-resistant fiber for reinforcement, when the active material is filled into the lattice substrate, it is possible to prevent the active material from coming off and falling off. In general, barium sulfate is used as a lead sulfate crystal growth inhibiting additive. When barium sulfate is used, it does not dissolve in the electrolytic solution and remains in the active material, so that it becomes a crystal nucleus of lead sulfate generated during charging, and fine lead sulfate can be formed. Lignin sulfonate is used as the anti-shrinking agent, and lignin sulfonate includes synthetic lignin and natural lignin derived from trees. desirable. By adding lignin, it is possible to prevent the negative electrode active material from being changed in shape during charge and discharge and to be aggregated, and to maintain the surface area of the active material. Moreover, by not containing carbon, the trickle current during trickle charge can be reduced, and the life performance can be sufficiently secured.

  As an additive added to the paste-like positive electrode active material, acid-resistant fibers for reinforcement and red lead are used. As the acid-resistant fiber for reinforcement, acrylic fiber, polyester fiber, PET fiber or the like can be used, and it is desirable to use PET fiber from the viewpoint of price and acid resistance. By using the acid-resistant fiber for reinforcement, when the active material is filled into the lattice substrate, it is possible to prevent the active material from coming off and falling off. Lead red can improve the chemical conversion during battery formation, increase the surface area of the positive electrode active material, increase the utilization rate of the positive electrode active material, and achieve both the chemical conversion of the active material and the durability of the active material. Therefore, it is desirable to add 5 to 25% by mass with respect to the lead powder. When the amount of lead is less than 5%, the effect of the lead is not sufficiently exhibited, and when it is 25% or more, the durability of the active material is remarkably lowered.

  The lead alloy for forming the positive electrode current collector is made of a lead-calcium-tin alloy. By making calcium content and tin content calcium: 0.08 mass% and tin: 1.6 mass% with respect to lead, the alloy composition becomes dense and a positive electrode current collector excellent in corrosion resistance is formed. It becomes possible to do.

  The lead alloy for forming the negative electrode current collector is not particularly limited, but it is common to use pure lead, calcium-tin alloy, antimony alloy, and from the viewpoint of life performance and ease of manufacturing. It is desirable to use a calcium-tin alloy.

  The positive and negative electrode plates are obtained by filling the respective pasty active materials described above into current collectors and aging and drying them. The current collector can be produced by an expanding method, a casting method, a forging method, or the like.

  In the control valve type lead storage battery of the present embodiment, for example, as shown in FIG. 1, a lead storage battery is assembled, and a predetermined amount of electrolyte is injected to form a battery case.

  When a plurality of cell chambers are provided in the battery case, electrode plate groups are accommodated in each cell chamber, and a predetermined polarity is obtained by mutually connecting between the electrode plate groups accommodated in the adjacent cell chambers and the opposite polarity straps. A lead-acid battery having a rated voltage and a rated capacity is configured. In the case of a single-cell battery case, terminals of a plurality of lead storage batteries can be connected in parallel or in series using a conductive plate to constitute a battery having a predetermined voltage and capacity.

  Examples of the present invention will be described in detail. In the following examples and comparative examples, the following positive electrode current collector and negative electrode current collector, paste-like positive electrode active material and paste-like negative electrode active material were used in common.

  A lead-calcium-tin alloy (calcium content: 0.1% by mass, tin content: 0.2% by mass) is melted and length: 144.0 mm, width: 147.0 mm, thickness: 2 depending on the casting method. A negative electrode current collector of 4 mm was produced.

  A lead-calcium-tin alloy (calcium content: 0.08 mass%, tin content: 1.6 mass%) is melted and length: 143.0 mm, width: 145.0 mm, thickness: 4 depending on the casting method. A 0.0 mm positive electrode current collector was produced.

  To 100% by mass of lead powder mainly composed of lead monoxide, 0.03% by mass of PET fiber, 0.5% by mass of barium sulfate, and 0.2% by mass of lignin sulfonate are added and mixed. Next, 10% by mass of water and 10% by mass of diluted sulfuric acid were added, and then a paste-like negative electrode active material prepared by kneading was prepared.

  To 100% by mass of lead powder containing lead monoxide as a main component, 17% by mass of red lead and 0.15% by mass of PET fiber are added and mixed, then 10% by mass of water and 17% by mass of dilute sulfuric acid. % And then kneaded to prepare a paste-like positive electrode active material.

  The conditions of the examples and comparative examples are shown in Table 1 below.

Example 1
<Production of electrode plate>
The positive electrode active material is pasted into the positive electrode current collector, the negative electrode current collector is pasted into the negative electrode active material, and the total weight (N) of the negative electrode active material and the total amount of positive electrode active material ( P was filled so that (N / P) = 0.7. The electrode plate filled with the paste-like positive electrode active material produced an unformed positive electrode plate through the following aging conditions 1 to 3 and drying conditions.

Aging condition 1: temperature: 80 ° C., humidity: 98%, time: 10 hours Aging condition 2: temperature: 65 ° C., humidity: 75%, time: 13 hours Aging condition 3: temperature: 40 ° C., humidity: 65% Time: 40 hours Drying conditions: Temperature: 60 ° C., Time: 24 hours The electrode plate filled with the paste-like negative electrode active material is
Aging condition: temperature: 40 ° C., humidity: 98%, time: 40 hours Drying condition: temperature: 60 ° C., time: 24 hours aging and drying conditions were performed to produce an unformed negative electrode plate.

<Production of retainer>
The mass M1 of glass fibers (first glass fibers) having a number average fiber diameter of 1.0 μm is 80% by mass, and the mass M2 of glass fibers (second glass fibers) having a number average fiber diameter of 3.5 μm is 20 masses. %, 3% by mass of aluminum sulfate as a flocculant, and 5% by mass of polypropylene emulsion resin were mixed to obtain a 1.6 mm thick retainer.

<Production of control valve type lead acid battery>
Three prepared unformed positive electrode plates and four unformed negative electrode plates were alternately stacked with the surface side having a high liquid absorption rate brought into contact with the unformed negative electrode plate through the produced retainer to produce an electrode plate group. . The produced electrode plate group is inserted into the battery case, and after the positive electrode terminal and the negative electrode terminal are welded to the electrode plate group, the battery case is sealed. Next, an electrolytic solution containing dilute sulfuric acid as a main component was injected from the exhaust plug port, a control valve was attached, a battery case was formed, and a control valve type lead storage battery was produced.

  The battery tank formation conditions were as follows: water temperature: 40 ° C., amount of electricity applied: 250% of the theoretical amount of electricity generated by the positive electrode active material, and time: 60 hours.

(Example 2)
The mass mixing ratio of the glass fibers during the production of the retainer is such that the mass M1 of the glass fibers (first glass fibers) having a number average fiber diameter of 1.0 μm is 70 mass%, and the glass fibers having a number average fiber diameter of 3.5 μm A control valve type lead-acid battery was produced in the same manner as in Example 1 except that the mass M2 of the second glass fiber) was 30% by mass.

(Example 3)
The filling amount of the paste-like positive electrode active material and the paste-like negative electrode active material at the time of preparation of the electrode plate is calculated as follows. A control valve type lead-acid battery was produced in the same manner as in Example 1 except that each was filled so that the ratio was (N / P) = 0.8.

Example 4
The filling amount of the paste-like positive electrode active material and the paste-like negative electrode active material at the time of preparation of the electrode plate is calculated based on the total weight (N) of the negative electrode active material and the total amount of the positive electrode active material (P) in the fully-charged control valve type lead storage battery. A control valve type lead-acid battery was produced in the same manner as in Example 1 except that each was filled so that the ratio was (N / P) = 0.9.

(Example 5)
The filling amount of the paste-like positive electrode active material and the paste-like negative electrode active material at the time of preparation of the electrode plate is calculated based on the total weight (N) of the negative electrode active material and the total amount of the positive electrode active material (P) in the fully-charged control valve type lead storage battery. A control valve type lead-acid battery was produced in the same manner as in Example 1 except that the ratio was (N / P) = 1.0.

(Example 6)
The filling amount of the paste-like positive electrode active material and the paste-like negative electrode active material at the time of preparation of the electrode plate is calculated based on the total weight (N) of the negative electrode active material and the total amount of the positive electrode active material (P) in the fully-charged control valve type lead storage battery. A control valve type lead-acid battery was produced in the same manner as in Example 1 except that each was filled so that the ratio was (N / P) = 1.1.

(Comparative Example 1)
A control valve type lead-acid battery was produced in the same manner as in Example 1 except that the glass fiber at the time of producing the retainer was 100% by mass of the glass fiber having a number average fiber diameter of 1.0 μm.

(Comparative Example 2)
The mass mixing ratio of the glass fibers at the time of producing the retainer is such that the mass M1 of the glass fibers (first glass fibers) whose number average fiber diameter is 1.0 μm is 60% by mass, and the glass fibers whose number average fiber diameter is 3.5 μm A control valve type lead-acid battery was produced in the same manner as in Example 1 except that the mass M2 of the second glass fiber) was 40% by mass.

(Comparative Example 3)
The filling amount of the paste-like positive electrode active material and the paste-like negative electrode active material at the time of preparation of the electrode plate is calculated as follows. A control valve type lead-acid battery was produced in the same manner as in Example 1 except that each was filled so that the ratio was (N / P) = 0.6.

(Comparative Example 4)
The filling amount of the paste-like positive electrode active material and the paste-like negative electrode active material at the time of preparation of the electrode plate is calculated as follows. A control valve type lead-acid battery was produced in the same manner as in Example 1 except that each was filled so that the ratio was (N / P) = 1.2.

(Discharge test)
The rated capacity confirmation test was conducted at 0.1 CA. That is, after the fully-charged control valve type lead storage battery is allowed to stand for 24 hours at an ambient temperature of 25 ° C., it is discharged at 0.1 CA to a final voltage of 1.8 V, and the discharge capacity at that time is measured. Thereafter, the battery was charged at a constant current of 0.1 CA until the charge amount reached 110% at an atmospheric temperature of 25 ° C. to obtain a fully charged state. The high rate discharge capacity confirmation test was conducted at 3.0 CA. That is, after the fully-charged control valve type lead-acid battery is left in an ambient temperature of 25 ° C. for 24 hours, it is discharged at 3.0 CA to a final voltage of 1.5 V, and the discharge capacity at that time is measured. Thereafter, the battery was charged at a constant current of 0.1 CA until the charge amount reached 110% at an atmospheric temperature of 25 ° C. to obtain a fully charged state.

<Test results>
Ratio of liquid absorption speed between one surface and the other surface of the retainer used for the produced control valve type lead storage battery, total mass (N) of the total negative electrode active material in the control valve type lead storage battery in a fully charged state, and positive electrode The ratio (N / P) of the total mass (P) of the active material, the rated capacity, and the high rate discharge capacity are shown in Table 2 as ratios based on Comparative Example 1.

(N / P) is in the range of 0.7 to 1.1, and the ratio of the liquid absorption speed between one surface of the retainer and the other surface is in the range of 1.3 to 1.4. Both capacity ratios improved. Since the rated capacity is limited by the positive electrode potential when (N / P) is in the range of 0.7 to 1.1, the ratio of the liquid absorption speed is in the range of 1.3 to 1.4, and the retainer has a high liquid absorption speed. Since the surface of the retainer is brought into contact with the negative electrode plate and the surface of the retainer having a low liquid absorption rate is brought into contact with the positive electrode plate, a gradient occurs in the liquid level. It is considered that the rated capacity has been improved.

  Since the high rate discharge capacity is limited by the negative electrode potential when (N / P) is in the range of 0.7 to 1.1, the ratio of the liquid absorption rate is set to the range of 1.3 to 1.4. Since the liquid level of the retainer in contact with the plate is increased, it is considered that diffusion and circulation of the electrolytic solution easily occur due to the capillary phenomenon, and the high rate discharge capacity is improved. When (N / P) is less than 0.7, the amount of the negative electrode active material is extremely low, so that the high rate discharge capacity is reduced. When (N / P) is higher than 1.1, the amount of the positive electrode active material Is extremely low, the rated capacity is reduced, and the effect of the retainer (the effect of the retainer having two surfaces including two types of glass fibers and different electrolyte absorption speeds) is not expected to appear. .

  According to the present invention, the mass ratio between the negative electrode active material and the positive electrode active material is adjusted, and the liquid absorption rate ratio of the electrolyte solution on one side and the other side of the retainer containing two types of glass fibers is adjusted. Thus, a lead storage battery having a high capacity and excellent discharge performance can be provided.

DESCRIPTION OF SYMBOLS 1 Control valve type lead acid battery 2 Positive electrode plate 3 Negative electrode plate 4 Retainer 4a One side 4b The other side 12 Battery case 13 Lid

Claims (5)

An electrode plate group in which a negative electrode plate and a positive electrode plate are laminated via a retainer, and an electrolyte solution, the retainer being in contact with the negative electrode plate in the laminating direction and the other surface in contact with the positive electrode plate in the laminating direction A control valve type lead acid battery comprising:
The active material mass ratio (N / P) of the total mass N of the negative electrode active material of the negative electrode plate and the total mass P of the positive electrode active material of the positive electrode plate in a fully charged state is in the range of 0.7 to 1.1,
The retainer includes a first glass fiber having a number average fiber diameter of 1.0 μm or less, and a second glass fiber having a number average fiber diameter of 3.0 μm or more,
The ratio (A / B) of the electrolyte solution absorption rate A on the one surface of the retainer to the electrolyte solution absorption rate B on the other surface is in the range of 1.3 to 1.4. There is a control valve type lead-acid battery.   The control valve type lead-acid battery according to claim 1, wherein the retainer has a mesh-like uneven surface on one surface and an irregular uneven surface on the other surface.   The number average fiber length of the retainer produced with the said glass fiber is 200-300 micrometers, The control valve type lead acid battery of Claim 1. The number average fiber diameter of the first glass fiber is 0.8 μm to 1.0 μm,
The number average fiber diameter of the second glass fiber is 3.5 μm to 5.0 μm,
The control valve type lead acid battery according to claim 3, wherein a ratio (M1 / M2) of a mass M1 of the first glass fiber and a mass M2 of the second glass fiber is 4 to 2.3.   The control valve type lead acid battery according to any one of claims 1 to 4, wherein the active material mass ratio (N / P) is in a range of 0.9 to 1.1.