WO2019116704A1

WO2019116704A1 - Control valve type lead acid storage battery

Info

Publication number: WO2019116704A1
Application number: PCT/JP2018/038015
Authority: WO
Inventors: 陽隆阿部; 聡美尾崎
Original assignee: 株式会社Ｇｓユアサ
Priority date: 2017-12-14
Filing date: 2018-10-12
Publication date: 2019-06-20
Also published as: JPWO2019116704A1; JP7188398B2; CN111295791A; CN111295791B

Abstract

This control valve type lead acid storage battery is provided with: a positive electrode plate which comprises a collector and a positive electrode material that is supported by the collector; a negative electrode plate; and a separator which is arranged between the positive electrode plate and the negative electrode plate, and which is configured from glass fibers. The compression ratio of the separator is from 1.2 to 1.8 (inclusive). The total pore volume per unit mass of the positive electrode material is 0.150 cm3/g or less. The positive electrode material contains fibers; and the average specific surface area of the fibers as determined by a BET method that uses a krypton gas as the adsorption gas is 0.20 m2/g or more.

Description

Control valve type lead storage battery

The technology disclosed herein relates to a valve-regulated lead-acid battery.

As one of the lead storage batteries, a control valve type lead storage battery (sealed lead storage battery) is known. The control valve type lead-acid battery has a high degree of freedom in the installation attitude since it does not have the electrolyte flowing inside, and maintenance is easy because it is not necessary to check the liquid amount and refill water. It is utilized as a power supply of a blackout power supply device, a communication base station, a two-wheeled vehicle, etc. (for example, refer to patent documents 1).

The control valve type lead-acid battery includes a positive electrode plate and a negative electrode plate. The positive electrode plate and the negative electrode plate each have a current collector and an active material supported by the current collector. Further, the control valve type lead-acid battery is disposed between the positive electrode plate and the negative electrode plate, and includes a separator made of glass fiber. The separator is impregnated with an electrolytic solution (for example, dilute sulfuric acid). In the control valve type lead storage battery, the positive electrode plate, the negative electrode plate, and the separator are accommodated in the cell chamber in a state of receiving a compressive force in the thickness direction.

JP, 2015-69965, A

In the control valve type lead-acid battery, since the positive electrode plate is accommodated in the cell chamber in a state of receiving a compressive force in the thickness direction, falling off of the positive electrode material from the current collector in the positive electrode plate is relatively difficult to occur. There is still a possibility that the positive electrode material may come off. The inventor of the present application has intensively studied, and if a specific configuration is adopted as the configuration of the control valve type lead-acid battery, the falling off of the positive electrode material from the current collector can be effectively suppressed. It has been newly found that the life characteristics of the storage battery can be dramatically improved.

In this specification, the technology capable of dramatically improving the life characteristics of the control valve type lead-acid battery by effectively suppressing the dropout of the positive electrode material from the current collector in the positive electrode plate of the control valve type lead-acid battery Disclose.

The valve-regulated lead-acid battery disclosed in the present specification includes a positive electrode plate having a current collector and a positive electrode material supported by the current collector, a negative electrode plate, and the positive electrode plate and the negative electrode plate. And a separator made of glass fiber, wherein the compression ratio of the separator is 1.2 or more and 1.8 or less, and the total pore volume per unit mass of the positive electrode material is 0.150 cm ³ / g or less, the positive electrode material contains a fiber, and the average specific surface area of the fiber according to the BET method using krypton gas as an adsorption gas is 0.20 m ² / g or more .

It is a front view which shows the external appearance structure of the lead storage battery 100 in this embodiment. It is a top view which shows the external appearance structure of the lead storage battery 100 in this embodiment. It is a top view which shows the internal structure of the lead storage battery 100 in this embodiment. It is explanatory drawing which shows YZ cross-section structure of the lead storage battery 100 in the position of IV-IV of FIG. FIG. 3 is an explanatory view showing a YZ cross-sectional configuration of a lead storage battery 100 at a position of VV in FIG. 2. FIG. 5 is an explanatory drawing showing an XZ cross-sectional configuration of a portion of the lead-acid battery 100 at a position VI-VI in FIG. 3. FIG. 8 is an explanatory view showing a method of housing the electrode plate group 20 in the cell chamber 16; It is explanatory drawing which shows a performance evaluation result. It is explanatory drawing which shows a performance evaluation result.

The techniques disclosed herein can be implemented as the following forms.

(1) A valve-regulated lead-acid battery disclosed in the present specification is a positive electrode plate having a current collector and a positive electrode material supported by the current collector, a negative electrode plate, the positive electrode plate and the negative electrode A separator disposed between the plate and the glass fiber, wherein a compression ratio of the separator is 1.2 or more and 1.8 or less, and total pores per unit mass of the positive electrode material The volume is 0.150 cm ³ / g or less, the positive electrode material contains fibers, and the average specific surface area of the fibers according to the BET method using krypton gas as an adsorption gas is 0.20 m ² / g It is above. The positive electrode plate is composed of a current collector and a positive electrode material. That is, the positive electrode material is obtained by removing the current collector from the positive electrode plate, and is generally referred to as an "active material". The inventor of the present invention has intensively studied and, by adopting the above-mentioned configuration, effectively suppresses the dropout of the positive electrode material from the current collector in the positive electrode plate, and the life of the valve-regulated lead-acid battery We have newly found that the characteristics can be dramatically improved.

That is, the specific surface area of the fiber to be contained in the positive electrode material has not been studied at all. Further, even if the specific surface area of the fibers contained in the positive electrode material is considered, the adsorption gas used when measuring the specific surface area of the fibers by the BET method was generally nitrogen gas. The inventors of the present application have found that, when nitrogen gas is used as an adsorption gas for various fibers, krypton gas is used as an adsorption gas even if there is no significant difference in the measurement results of the specific surface area of the fibers. The specific surface area is measured, and when fibers having an average specific surface area thus measured of 0.20 m ² / g or more are selectively used, removal of the positive electrode material from the current collector in the positive electrode plate is effectively suppressed. It has been newly found that the life characteristics of the valve-regulated lead-acid battery can be dramatically improved.

However, if the total pore volume per unit mass of the positive electrode material is excessively large, the density of the positive electrode material is excessively low and the structure is easily broken, so that the separation of the positive electrode material from the current collector can be suppressed. It may disappear. Also, if the compression ratio of the separator is too small, the thickness of the separator becomes thinner as the electrode plate expands and contracts due to repeated charging and discharging of the valve-regulated lead-acid battery, and the separator and electrode The area which can not be in contact with the plate increases to cause a capacity reduction, which may lower the life characteristics. In addition, when the compression ratio of the separator is excessively large, an excessive pressure is applied to the separator, the gap inside the separator becomes excessively small, and the function of the electrolyte holding by the separator is excessively reduced, causing a capacity reduction. Thus, the life characteristics may be lowered. The inventor of the present application has made intensive studies to set the compression ratio of the separator to 1.2 or more and 1.8 or less, and the total pore volume per unit mass of the positive electrode material to be 0.150 cm ³ / g or less. If, by using a fiber having an average specific surface area of 0.20 m ² / g or more according to the BET method using krypton gas as an adsorption gas, as a fiber for a positive electrode, dropout of the positive electrode material from the current collector in the positive electrode plate Was found to be able to dramatically improve the life characteristics of lead acid batteries.

(2) In the control valve type lead storage battery, the total pore volume per unit mass of the positive electrode material may be 0.104 cm ³ / g or more. If the total pore volume per unit mass of the positive electrode material is excessively small, it is considered that the reactivity of the positive electrode material becomes excessively low and, as a result, the capacity characteristics of the lead storage battery become low. On the other hand, in the present valve-regulated lead-acid battery, the total pore volume per unit mass of the positive electrode material is not excessively small at 0.104 cm ³ / g or more. Therefore, according to the control valve type lead storage battery, it is possible to suppress a decrease in the reactivity of the positive electrode material, and while improving the life characteristics of the control valve type lead storage battery dramatically, the capacity characteristics of the control valve type lead storage battery Can be improved.

(3) In the control valve type lead storage battery, the total pore volume per unit mass of the positive electrode material may be 0.132 cm ³ / g or more. According to the present control valve type lead storage battery, the decrease in the reactivity of the positive electrode material can be extremely effectively suppressed. Therefore, while the life characteristics of the control valve type lead storage battery are dramatically improved, the control valve type lead storage battery The capacitance characteristics of can be very effectively improved.

(4) In the control valve type lead storage battery, the fibers may be acrylic fibers. According to the present valve-regulated lead storage battery, it is possible to easily obtain a fiber having an average specific surface area of 0.20 m ² / g or more according to the BET method using krypton gas as an adsorption gas.

A. Embodiment:
A-1. Basic configuration:
(Configuration of lead storage battery 100)
FIG. 1 is a front view showing an appearance configuration of the lead storage battery 100 in the present embodiment, FIG. 2 is a top view showing an appearance configuration of the lead storage battery 100, and FIG. 3 shows an internal configuration of the lead storage battery 100. It is a top view (figure which shows the state which removed the lid 14 mentioned later), FIG. 4 is explanatory drawing which shows YZ cross-section structure of the lead storage battery 100 in the position of IV-IV of FIG. FIG. 6 is an explanatory view showing a YZ cross-sectional configuration of the lead storage battery 100 at the position of VV of 2 and FIG. 6 is an explanatory view showing an XZ cross-sectional configuration of a part of the lead storage battery 100 at the position of VI-VI in FIG. . For convenience of illustration, only a part (three) of a plurality of electrode plate groups 20 (and straps 52 and 54 connected thereto) which will be described later are shown in FIG. 3 and FIG. 4 and FIG. In FIG. 5, a part of the configuration is omitted so that the configuration of the electrode group 20 can be easily understood. In each figure, mutually orthogonal XYZ axes for specifying the direction are shown. In this specification, for convenience, the positive direction of the Z-axis is referred to as "upward" and the negative direction of the Z-axis is referred to as "downward". However, the lead storage battery 100 is actually different from such an orientation. It may be installed in the direction.

The lead storage battery 100 of the present embodiment is a control valve type lead storage battery (sealed lead storage battery). The control valve type lead-acid battery has a high degree of freedom in the installation attitude since it does not have the electrolyte flowing inside, and maintenance is easy because it is not necessary to check the liquid amount and refill water. It is used as a power supply of a blackout power supply device, a communication base station, a two-wheeled vehicle, etc. The lead storage battery 100 includes a housing 10, a positive electrode terminal member 30, a negative electrode terminal member 40, and a plurality of electrode plate groups 20. Hereinafter, the positive electrode terminal member 30 and the negative electrode terminal member 40 are collectively referred to as “

terminal members

30, 40”.

(Configuration of case 10)
The housing 10 has a battery case 12 and a lid 14. The battery case 12 is a substantially rectangular container having an opening on the top surface, and is formed of, for example, a synthetic resin. The lid 14 is a member disposed so as to close the opening of the battery case 12 and is made of, for example, a synthetic resin. By bonding the peripheral portion of the lower surface of the lid 14 and the peripheral portion of the opening of the battery case 12 by, for example, heat welding, a space in which the air tightness with the outside is maintained is formed in the housing 10.

A control valve (exhaust valve) 60 is disposed on the lid 14. The control valve 60 is normally closed and has a function of opening when the internal pressure of the lead storage battery 100 rises and releasing the internal pressure.

The space in the housing 10 is divided into a plurality of (six in the present embodiment) cell chambers 16 aligned in a predetermined direction (the X-axis direction in the present embodiment) by a plurality of (five in the present embodiment) partition walls 58. It is divided. Hereinafter, the direction (X-axis direction) in which the plurality of cell chambers 16 are arranged is referred to as “cell alignment direction”. One electrode plate group 20 is accommodated in each cell chamber 16 in the housing 10. In the present embodiment, since the space in the housing 10 is divided into six cell chambers 16, the lead storage battery 100 is provided with six electrode plate groups 20.

(Configuration of electrode group 20)
As shown in FIGS. 4 to 6, the electrode plate group 20 includes a plurality of positive electrode plates 210, a plurality of negative electrode plates 220, and a separator 230. The plurality of positive electrode plates 210 and the plurality of negative electrode plates 220 are arranged such that the positive electrode plates 210 and the negative electrode plates 220 are alternately arranged. The separator 230 is disposed between the positive electrode plate 210 and the negative electrode plate 220 adjacent to each other, and is sandwiched between the positive electrode plate 210 and the negative electrode plate 220. The electrode plate group 20 may include other members (for example, a non-woven sheet disposed between the positive electrode plate 210 and the negative electrode plate 220) other than the positive electrode plate 210, the negative electrode plate 220, and the separator 230. Hereinafter, the positive electrode plate 210 and the negative electrode plate 220 will be collectively referred to as “

electrode plates

210 and 220”.

The positive electrode plate 210 includes a positive electrode current collector 212 and a positive electrode active material 216 supported by the positive electrode current collector 212. The positive electrode current collector 212 is a conductive member having bones arranged in a substantially lattice shape or a mesh shape, and is formed of, for example, lead or a lead alloy. Further, the positive electrode current collector 212 has a positive electrode ear 214 projecting upward in the vicinity of the upper end thereof. The positive electrode active material 216 contains lead dioxide and a positive electrode fiber 217 described later. The positive electrode active material 216 may further contain other known additives. In the positive electrode plate 210 having such a configuration, for example, the positive electrode current collector 212 is coated or filled with a positive electrode active material paste mainly composed of lead monoxide, water and dilute sulfuric acid, and the positive electrode active material paste is dried. It can be produced by performing known chemical conversion treatment after the treatment. The positive electrode active material 216 in the present embodiment is obtained by removing the positive electrode current collector 212 from the positive electrode plate 210, and corresponds to the positive electrode material in the claims.

The negative electrode plate 220 has a negative electrode current collector 222 and a negative electrode active material 226 supported by the negative electrode current collector 222. The negative electrode current collector 222 is a conductive member having bones arranged in a substantially lattice shape or a mesh shape, and is made of, for example, lead or a lead alloy. In addition, the negative electrode current collector 222 has a negative electrode ear 224 protruding upward in the vicinity of the upper end thereof. The negative electrode active material 226 contains lead (cavernous lead). The negative electrode active material 226 may further contain other known additives (eg, fiber, carbon, lignin, barium sulfate, etc.). In the negative electrode plate 220 having such a configuration, for example, after applying or filling a negative electrode active material paste containing lead to the negative electrode current collector 222 and drying the negative electrode active material paste, known conversion treatment is performed. Can be produced by

The separator 230 is made of glass fiber which is an insulating material, and is a mat-like member that can be elastically deformed in the thickness direction. The separator 230 is impregnated with an electrolytic solution (for example, dilute sulfuric acid). Thus, the separator 230 has a function to prevent the short circuit between the

bipolar plates

210 and 220 and to retain the electrolytic solution.

As shown in FIG. 7, the thickness W 0 of the electrode plate group 20 in a state not accommodated in the cell chamber 16 (hereinafter referred to as “natural state”) is the width of the cell chamber 16 (ie, a pair adjacent to each other The distance between the partition walls 58 (or the distance between the partition walls 58 and the side wall of the battery case 12) is set to a value slightly larger than W1. When manufacturing the lead storage battery 100, a compressive force is applied to the electrode plate group 20 in a natural state in the thickness direction by a pressing device (not shown). As a result, the thickness of the electrode plate group 20 becomes equal to or less than the width W 1 of the cell chamber 16 by the elastic contraction of the separator 230 in the thickness direction. In this state, the electrode plate group 20 is inserted into the cell chamber 16. In a state in which the electrode group 20 is accommodated in the cell chamber 16, the electrode group 20 receives a compressive force in the thickness direction (in the present embodiment, in the X-axis direction). Therefore, the

respective electrode plates

210 and 220 constituting the electrode group 20 are in a state of being in good contact with the separator 230 holding the electrolytic solution.

As shown in FIGS. 3 to 5, the positive electrode ear portions 214 of the plurality of positive electrode plates 210 constituting the electrode plate group 20 are connected to a positive electrode side strap 52 formed of, for example, lead or a lead alloy. That is, the plurality of positive electrode plates 210 are electrically connected in parallel via the positive electrode side strap 52. Similarly, the negative electrode ear portions 224 of the plurality of negative electrode plates 220 constituting the electrode plate group 20 are connected to the negative electrode side strap 54 formed of, for example, lead or a lead alloy. That is, the plurality of negative electrode plates 220 are electrically connected in parallel via the negative electrode side strap 54. Hereinafter, the positive side strap 52 and the negative side strap 54 are collectively referred to as "straps 52, 54".

In the lead storage battery 100, the negative electrode side strap 54 accommodated in one cell chamber 16 is connected to one side (for example, the X axis positive side) of the one cell chamber 16 via a connecting member 56 formed of, for example, lead or lead alloy. It connects to the positive electrode side strap 52 accommodated in the other cell chamber 16 adjacent to direction direction). Further, the positive side strap 52 accommodated in the one cell chamber 16 is connected to the other cell chamber 16 adjacent to the other side (for example, the X-axis negative direction side) of the one cell chamber 16 via the connection member 56. Are connected to the negative side strap 54 housed in FIG. That is, the plurality of electrode plate groups 20 included in the lead storage battery 100 are electrically connected in series via the

straps

52 and 54 and the connection member 56. As shown in FIG. 4, the positive side strap 52 accommodated in the cell chamber 16 positioned at one end (the positive side in the X-axis direction) in the cell alignment direction is not the connection member 56 but a positive pole post described later. Connected to 34. Further, as shown in FIG. 5, the negative side strap 54 accommodated in the cell chamber 16 positioned at the other end (the negative side of the X axis) in the cell alignment direction is not the connection member 56 but a negative pole post described later. Connected to the 44.

(Configuration of terminal members 30, 40)
As shown in FIGS. 1 and 2, the positive electrode terminal member 30 is disposed in the vicinity of the end of one side (the positive side in the X-axis direction) of the housing 10 in the cell alignment direction, and the negative electrode terminal member 40 is It is arranged near the end of the other side (X-axis negative direction side) in the cell alignment direction in the housing 10.

As shown in FIG. 4, the positive electrode terminal member 30 includes a positive electrode bushing 32, a positive electrode post 34, and a positive electrode terminal portion 36. The positive electrode side bushing 32 is a substantially cylindrical conductive member in which a hole penetrating in the vertical direction is formed, and is formed of, for example, a lead alloy. The positive electrode side bushing 32 is embedded in the lid 14 by insert molding. The positive electrode post 34 is a substantially cylindrical conductive member, and is formed of, for example, a lead alloy. The positive electrode column 34 is inserted into the hole of the positive electrode side bushing 32 and is joined to the positive electrode side bushing 32 by welding, for example. The lower end portion of the positive electrode column 34 protrudes downward from the lower end portion of the positive electrode bushing 32, and further protrudes downward from the lower surface of the lid 14, and as described above, one side in the cell alignment direction (X-axis positive direction side It is connected to the positive side strap 52 accommodated in the cell chamber 16 located at the end of. The positive electrode side terminal portion 36 is, for example, a substantially L-shaped conductive member, and is formed of, for example, a lead alloy. The upper end portion of the positive electrode terminal portion 36 protrudes upward from the upper surface of the lid 14, and the lower end portion of the positive electrode terminal portion 36 is electrically connected to the upper end portion of the positive electrode post 34. The periphery of a portion of the top surface of the lid 14 through which the positive electrode terminal portion 36 penetrates is sealed by, for example, a resin member 70. The positive electrode side terminal portion 36 and the positive electrode post 34 may be an integral member.

As shown in FIG. 5, the negative electrode terminal member 40 includes a negative electrode bushing 42, a negative electrode post 44, and a negative electrode terminal portion 46. The negative electrode side bushing 42 is a substantially cylindrical conductive member in which a hole penetrating in the vertical direction is formed, and is formed of, for example, a lead alloy. The negative electrode side bushing 42 is embedded in the lid 14 by insert molding. The negative electrode post 44 is a substantially cylindrical conductive member, and is formed of, for example, a lead alloy. The negative electrode post 44 is inserted into the hole of the negative electrode side bushing 42 and is joined to the negative electrode side bushing 42 by welding, for example. The lower end portion of the negative electrode post 44 protrudes downward from the lower end portion of the negative electrode side bushing 42, and further protrudes downward from the lower surface of the lid 14, and as described above, the other side in the cell alignment direction Is connected to the negative side strap 54 housed in the cell chamber 16 located at the end of. The negative electrode side terminal portion 46 is, for example, a substantially L-shaped conductive member, and is formed of, for example, a lead alloy. The upper end portion of the negative electrode terminal portion 46 protrudes upward from the upper surface of the lid 14, and the lower end portion of the negative electrode terminal portion 46 is electrically connected to the upper end portion of the negative electrode post 44. The periphery of a portion of the upper surface of the lid 14 through which the negative electrode terminal portion 46 penetrates is sealed by, for example, a resin member 70. Note that the negative electrode side terminal portion 46 and the negative electrode post 44 may be an integral member.

When the lead storage battery 100 is discharged, a load (not shown) is connected to the positive electrode terminal portion 36 of the positive electrode terminal member 30 and the negative electrode terminal portion 46 of the negative electrode terminal member 40. Electric power generated by the reaction at the positive electrode plate 210 (the reaction of lead dioxide to lead sulfate) and the reaction at the negative electrode plate 220 (the reaction of lead sulfate to lead sulfate) is supplied to the load. Further, when the lead storage battery 100 is charged, a power supply (not shown) is connected to the positive electrode terminal portion 36 of the positive electrode terminal member 30 and the negative electrode terminal portion 46 of the negative electrode terminal member 40 and supplied from the power supply. The generated electric power causes a reaction (a reaction of lead sulfate to lead dioxide) at each positive electrode plate 210 of each electrode plate group 20 and a reaction at a negative electrode plate 220 (a reaction of lead sulfate to lead (cavernous lead)). The lead storage battery 100 is charged.

A-2. Detailed Configuration of Lead Acid Battery 100:
A-2-1. Detailed Configuration of Separator 230:
In the lead storage battery 100 of the present embodiment, the compression ratio of each separator 230 constituting the electrode plate group 20 accommodated in each cell chamber 16 is 1.2 or more and 1.8 or less. Here, the compression ratio of the separator 230 refers to the thickness D1 of the separator 230 in a state in which the electrode plate group 20 is accommodated in the cell chamber 16 (hereinafter referred to as “accommodated state”), as shown in FIGS. The ratio (= D0 / D1) of the thickness D0 of the separator 230 when the electrode group 20 is not accommodated in the cell chamber 16 (natural state). That is, the compression ratio of the separator 230 is an index value indicating how much the separator 230 in the storage state is elastically shrunk from the natural state. In the following description, the condition that the compression ratio of the separator 230 is 1.2 or more and 1.8 or less is referred to as "a specific condition regarding the separator".

In addition, the compression ratio of the separator 230 which comprises the lead storage battery 100 shall be specified as follows.
(1) Disassemble the fully charged lead-acid battery 100 according to the Battery Industry Association (SBA), and take out the electrode plate group 20 from the cell chamber 16. When the electrode plate group 20 is taken out of the cell chamber 16, the separator 230 constituting the electrode plate group 20 restores and expands in the thickness direction.
(2) The

electrode plates

210 and 220 and the separators 230 constituting the electrode plate group 20 taken out are washed with water for 3 hours or more, and then dried.
(3) After drying, the thickness of each positive electrode plate 210 and each negative electrode plate 220 is measured with a caliper. The average value of the measured thickness is calculated for each of the

electrode plates

210 and 220. Similarly, after drying, the thickness (the thickness D0 in the natural state) of each separator 230 is measured with a caliper. Since the thickness of the separator 230 is easily changed, the thickness is measured on the basis of 200 N / dm ² . For each separator 230, the average value of the measured thickness is calculated.
(4) Measure the width W1 of the cell chamber 16 with a caliper. When the width W1 is different between the upper portion and the lower portion in the cell chamber 16, an average value of the widths W1 of the upper and lower portions is calculated.
(5) The compression ratio of the separator 230 is calculated based on the following equation.
The compression ratio of the separator 230 = the thickness D0 of the separator 230 in the natural state / the thickness D1 of the separator 230 in the storage state
Here, the thickness D0 of the separator 230 in the natural state is a measurement value in the above (3).
In addition, the thickness D1 of the separator 230 in the storage state is calculated based on the following equation.
Thickness D1 of the separator 230 in the storage state
= (Width W1 of cell chamber 16-(thickness of positive electrode plate 210 × number of positive electrode plates 210 constituting electrode plate group 20)-(thickness of negative electrode plate 220 × negative electrode plate 220 constituting electrode group 20) Number of sheets) / (Number of positive electrodes 210 constituting electrode group 20 + number of negative electrodes 220 constituting electrode group 20) -1)
However, when the electrode plate group 20 includes other members (for example, non-woven sheets) other than the positive electrode plate 210, the negative electrode plate 220, and the separator 230, the thickness D1 of the separator 230 in the storage state is obtained by the above equation The value is obtained by subtracting the thickness of the other member from the value.

A-2-2. Detailed configuration of positive electrode active material 216:
As shown in FIG. 4, in the lead storage battery 100 of the present embodiment, the positive electrode active material 216 contains a fiber (hereinafter, referred to as “fiber for positive electrode”) 217 in addition to lead dioxide. In the present embodiment, the average specific surface area of the fibers 217 for positive electrode according to the BET method using krypton gas as adsorption gas (hereinafter, also simply referred to as “average specific surface area of the fibers 217 for positive electrode”) is 0.20 m ² / g or more It is. In addition, since krypton gas has a lower saturated vapor pressure than, for example, nitrogen gas, if krypton gas is used as an adsorption gas for measurement of the specific surface area by BET method, a relatively low specific surface area can be accurately measured. it can. For example, if krypton gas is used as the adsorption gas, the surface area of the fine wrinkles on the surface of the positive electrode fiber 217, which is difficult to measure when nitrogen gas is used, can be accurately measured. Therefore, when nitrogen gas is used as the adsorption gas for various fibers, the specific surface area of the fibers can be obtained using krypton gas as the adsorption gas, even if there is no significant difference in the measurement results of the specific surface area of the fibers. Significant differences may be identified in the measurement results of

The fibers 217 for the positive electrode are, for example, acrylic fibers, polypropylene fibers, polyester fibers, polyethylene fibers, PET fibers, and rayon fibers. Acrylic fibers are produced by wet spinning in which a polymer is dissolved in a solvent and the fibers are spun in a liquid called a coagulant. At this time, the fiber part and the solvent part are separated (segregated), and the part from which the solvent part is removed appears as wrinkles. Therefore, in general, many fine wrinkles are formed on the surface of acrylic fiber. Therefore, it is preferable to use an acrylic fiber as the positive electrode fiber 217 because the positive electrode fiber 217 having an average specific surface area according to the BET method using krypton gas as the adsorption gas can be easily obtained. . In addition, when using an acrylic fiber as the fiber 217 for positive electrodes, the average specific surface area of the fiber 217 for positive electrodes by BET method which used krypton gas as adsorption gas can be enlarged to about 0.40 m < ² > / g. .

Moreover, in the lead storage battery 100 of the present embodiment, the total pore volume per unit mass of the positive electrode active material 216 is 0.150 cm ³ / g or less. Incidentally, the total pore volume per unit mass of the positive electrode active material 216, 0.104cm ³ / g or more, 0.150cm ³ / g and more preferably at most, 0.132cm ³ / g or more, 0.150Cm It is more preferable that it is ³ / g or less. The total pore volume per unit mass of the positive electrode active material 216 can be adjusted by changing the formulation (blending ratio of lead powder, water, and dilute sulfuric acid) at the time of manufacturing the positive electrode active material 216. For example, when the mixing ratio of dilute sulfuric acid and water is increased, the total pore volume per unit mass of the positive electrode active material 216 is increased.

In the following description, the total pore volume per unit mass of the positive electrode active material 216 is 0.150 cm ³ / g or less, the positive electrode active material 216 contains the fiber 217 for the positive electrode, and the krypton gas is adsorbed. The condition that the average specific surface area of the fibers 217 for the positive electrode according to the BET method used as a gas is 0.20 m ² / g or more is referred to as “the specific condition regarding the positive electrode active material”.

The average specific surface area according to the BET method using krypton gas as an adsorption gas for the positive electrode fibers 217 contained in the positive electrode active material 216 constituting the positive electrode plate 210 of the lead storage battery 100 is specified as follows: Do.
(1) Disassemble the lead storage battery 100 and collect the positive electrode plate 210.
(2) In order to remove the sulfuric acid, the collected positive electrode plate 210 is washed with water.
(3) The positive electrode active material 216 is collected from the positive electrode plate 210.
(4) The collected positive electrode active material 216 is dissolved in a mixed solution of nitric acid and hydrogen peroxide.
(5) Filter the solution of (4).
(6) Sample about 0.4 g of sample (fiber) from the residue on filter paper.
(7) Using a specific surface area measurement device (Tristar II 3020 series manufactured by Shimadzu Corporation), measure the specific surface area of each fiber by the BET method using krypton gas as an adsorption gas.
(8) Calculate the average value of the specific surface area of each fiber.

Moreover, the total pore volume per unit mass of the positive electrode active material 216 which comprises the positive electrode plate 210 of the lead storage battery 100 shall be specified as follows.
(1) Disassemble the lead storage battery 100 and collect the positive electrode plate 210.
(2) In order to remove the sulfuric acid, the collected positive electrode plate 210 is washed with water.
(3) About 1 g of a sample (positive electrode active material 216) is collected from the positive electrode plate 210.
(4) The total pore volume is measured by mercury porosimetry using a mercury porosimeter (Autopore IV 9500 series manufactured by Shimadzu Corporation) with the collected positive electrode active material 216 as a target.
(5) The average value of the measured values of the total pore volume of each positive electrode active material 216 is taken as the total pore volume per unit mass of the positive electrode active material 216.

A-3. Performance evaluation:
A plurality of lead-acid battery samples (S1 to S21) were prepared, and performance evaluation was performed on the samples. 8 and 9 are explanatory diagrams showing the results of performance evaluation. In addition, about sample S5 used as the reference | standard among several samples, it describes in common in FIG. 8 and FIG. 9 (it shows in a thick frame in each figure).

A-3-1. For each sample:
As shown in FIGS. 8 and 9, each sample has a compression ratio of the separator, a total pore volume of the positive electrode active material, and an average specific surface area of the positive electrode fibers different from each other. More specifically, in the samples S1 to S13 shown in FIG. 8, the compression ratio of the separators is the same value (1.5), but the total pore volume of the positive electrode active material and the average of the fibers for the positive electrode The specific surface areas are different from one another. In FIG. 8, the samples S1 to S13 are arranged in the ascending order of the total pore volume of the positive electrode active material, and each sample having the same total pore volume of the positive electrode active material is the average of fibers for the positive electrode. They are arranged in ascending order of specific surface area.

Further, in the samples S5 and S14 to S21 shown in FIG. 9, although the total pore volume of the positive electrode active material is all the same value (0.104 cm ³ / g), the compression ratio of the separator and the positive electrode fibers The average specific surface areas are different from one another. In FIG. 9, the samples S14 to S21 are arranged in the ascending order of the compression ratio of the separators, and the samples having the same compression ratio of the separators are arranged in the ascending order of the average specific surface area of the positive electrode fibers. There is.

In the samples S1 to S3, S6 to S12, and S16 to S19, specific conditions related to the separator that the lead storage battery 100 of the above-described embodiment satisfies (conditions that the compression ratio of the separator is 1.2 or more and 1.8 or less) And specific conditions for the positive electrode active material (total pore volume per unit mass of positive electrode active material is 0.150 cm ³ / g or less, the positive electrode active material contains a fiber for positive electrode, and krypton gas The condition that the average specific surface area of the fiber for positive electrode according to the BET method used as the adsorption gas is 0.20 m ² / g or more is satisfied.

On the other hand, the samples S4, S5, S13 to S15, S20, and S21 do not satisfy one or both of the above-described specific conditions for the separator and the specific conditions for the positive electrode active material. Specifically, the samples S14 and S15 do not satisfy the specific condition on the separator because the compression ratio of the separator is relatively small at 1.1. In addition, the samples S20 and S21 do not satisfy the specific condition on the separator because the compression ratio of the separator is relatively large at 1.9. Further, the samples S4 and S5 do not satisfy the specific conditions for the positive electrode active material, because the average specific surface area of the positive electrode fibers is relatively small at 0.16 m ² / g or 0.18 m ² / g. Further, since the total pore volume per unit mass of the positive electrode active material is relatively large at 0.159 cm ³ / g, the sample S13 does not satisfy the specific condition regarding the positive electrode active material.

In all samples, acrylic fibers are used as fibers for the positive electrode, and the average diameter of the acrylic fibers is 16.7 μm, and the aspect ratio of the acrylic fibers (the average length with respect to the average diameter of the fibers) Ratio) is 30 to 400. In all samples, the content ratio of the positive electrode fibers in the positive electrode active material is 0.05% by mass (wt%) to 0.40% by mass. Further, in all the samples, the negative electrode active material constituting the negative electrode plate contains, as fibers for the negative electrode, PET-based fibers having an average specific surface area of 0.20 m ² / g according to the BET method using krypton gas as an adsorption gas. doing.

The preparation method of each sample is as follows.
(1) Production of positive electrode plate Raw material lead powder (a mixture of lead oxide mainly composed of lead and lead monoxide), water, diluted sulfuric acid (density 1.40 g / cm ³ ), and predetermined lengths The paste for the positive electrode active material was obtained by mixing with the cut synthetic resin fiber (hereinafter, referred to as “fiber for positive electrode”). It is known that the positive electrode active material can change its density by changing the mixing ratio of dilute sulfuric acid and water, and the positive electrode active material used in this performance evaluation is also the above dilute sulfuric acid and water. This is achieved by changing the compounding ratio of Further, a lead sheet made of a ternary alloy of lead, calcium and tin (hereinafter referred to as "Pb-Ca-Sn alloy") was expanded, and then a positive electrode grid (positive electrode current collector) was produced. The expanded network of the positive electrode current collector is filled with the paste for the positive electrode active material, and it is aged and dried by a conventional method to form an unformed positive electrode plate (height: 115 mm, width: 137.5 mm, thickness: 1.5 mm) I got

(2) Preparation of negative electrode plate Raw material lead powder (a mixture of lead oxide consisting mainly of lead and lead monoxide), water, diluted sulfuric acid (density 1.40 g / cm ³ ), and predetermined lengths The paste for negative electrode active material was obtained by mixing the cut | judged synthetic resin fiber (henceforth "fiber for negative electrodes") and the negative electrode additive (lignin, carbon, barium sulfate) of a predetermined | prescribed ratio. A plate lead sheet made of a Pb—Ca—Sn alloy was expanded in the same manner as in the positive electrode grid (positive electrode current collector), and then a negative electrode grid (negative electrode current collector) was produced. The expanded network of the negative electrode current collector is filled with the paste for negative electrode active material, and the negative electrode plate (height: 115 mm, width: 137.5 mm, thickness 1) is formed by aging and drying in the usual manner as in the positive electrode plate. .3 mm).

(3) Preparation of Sample Battery Using the positive electrode plate and the negative electrode plate prepared in the above (1) and (2) and the mat-like separator made of glass fiber separately prepared, the positive electrode plate and the negative electrode plate are separated by the separator After sandwiching and laminating alternately, a plurality of positive electrode plates and a plurality of negative electrodes were welded with a lead part to produce an electrode plate group. The above electrode plate group is inserted into a resin (polypropylene) battery case so that 6 cells are connected in series, and after welding each electrode plate group (five places) between cells, a resin (polypropylene) lid and The battery case was joined, and then both terminal parts (positive and negative electrode terminal parts) were welded to produce a sample battery. The compression ratio of the separator was adjusted by adjusting the width of the cell chamber in the battery case using a spacer. Thereafter, after initial charging by a conventional method, a sample battery having an electrolyte density of 1.33 was obtained.

A-3-2. Evaluation items and evaluation methods:
Each sample of the lead-acid battery was used to evaluate two items of life characteristics and initial capacity characteristics.

The evaluation of capacity characteristics was performed as follows. That is, for each sample of the lead-acid battery, the 3-hour rate capacity is measured by the method shown in a) to d) below, and the 3-hour rate capacity in sample S5 is assumed to be 100 (shown by bold lines in FIGS. ), 3 hour rate capacity in each sample was expressed as a relative value.
a) About the sample: (1) Charge for 8 hours with a charge current of up to 0.4 CA with a constant voltage charge method whose upper limit is 14.7 V, or (2) 5-stage constant current charge method: 14.4 V switching voltage In addition to 4-stage 0.2 CA → 0.1 CA → 0.05 CA → 0.025 CA, respectively, in the constant current charging method (moving to the next charging stage), +5 stage indentation constant current charging 0.025 CA × 2. Fully charge on condition of 5h (fixed).
b) After charging is completed, the sample is allowed to stand at 25 ± 2 ° C., and discharge of the following c) is started within the water tank for 5 hours or more and 24 hours or less and for 10 hours or more in the air tank within 24 hours Do.
c) The sample is discharged at a constant reference current I ₃ (A) until the discharge termination voltage (1.65 × cell number (V)) is reached. The reference current I ₃ (A) is a value obtained by the following equation.
I ₃ = _C _3/3
(However, _{C 3} is 3-hour-rate rated capacity (Ah))
d) Measure the discharge duration time in the above c) and calculate the 3-hour rate capacity.

Moreover, the evaluation of the lifespan was performed as follows. That is, for each sample of the lead storage battery, a life test was conducted by the method shown in the following a) to d) to determine the number of times of life. The number of lifespans of the sample S5 is set to 100 (indicated by bold lines in FIGS. 8 and 9), and the number of lifespans of each sample is represented by a relative value.
a) Place the sample in a 25 ± 2 ° C. air bath throughout the entire test period.
b) Connect the sample to the life test device, discharge for 2.4 hours with the reference current I ₃ (A) described above, and then charge with the 5-stage constant current charge described above. One cycle of this discharge and charge is taken as one life.
c) For every 50 charge and discharge cycles, calculate the 3-hour rate capacity by the method described above. However, also when the terminal voltage at the end of the discharge in the above b) reaches 1.65 V / cell, the 3-hour rate capacity is similarly calculated.
d) If the 3-hour rate capacity calculated in the above c) falls to 80% or less of the 3-hour rate rated capacity, the 3-hour rate capacity is calculated again, and the 3-hour rate capacity is the 3-hour rate rated capacity When it is confirmed that the value does not exceed 80%, the test is ended, and the number of lifespans is obtained from the relationship between the number of cycles and the capacity at that time. The number of capacity tests in c) is also added to the number of lifetimes.

A-3-3. Evaluation results:
As shown in FIG. 8 and FIG. 9, the specific condition (the condition that the compression ratio of the separator is 1.2 or more and 1.8 or less) related to the above-mentioned separator and the specific condition (the unit of the positive electrode active material) The total pore volume per mass is 0.150 cm ³ / g or less, the positive electrode active material contains a positive electrode fiber, and the average ratio of positive electrode fibers by BET method using krypton gas as an adsorption gas In the samples S1 to S3, S6 to S12, and S16 to S19 which satisfy both the condition that the surface area is 0.20 m ² / g or more, the result of evaluation of the life characteristics is “113” or more, and the samples As compared with the evaluation result "100" of the life characteristics of S5, the life characteristics were dramatically improved.

On the other hand, in samples S4 and S5 that do not satisfy the specific conditions for the positive electrode active material because the average specific surface area of the positive electrode fibers is less than 0.20 m ² / g, the evaluation of the life characteristics is as good as "100" or less It was not a result. In the samples S4 and S5, since the average specific surface area of the positive electrode fibers is too small, the positive electrode fibers do not adhere well to other components in the positive electrode active material, and the binding force of the positive electrode active material by the positive electrode fibers is small. As a result, it is considered that the life characteristics are lowered because the separation of the positive electrode active material from the current collector can not be effectively suppressed.

In the sample S13 which does not satisfy the specific conditions for the positive electrode active material because the total pore volume per unit mass of the positive electrode active material exceeds 0.150 cm ³ / g, the evaluation of the life characteristics is as good as “83” There was no result. In sample S13, the total pore volume per unit mass of the positive electrode active material is excessively large. That is, in the sample S13, the density of the positive electrode active material is excessively low, and is easily broken. Therefore, in the sample S13, although the average specific surface area of the positive electrode fiber is 0.20 m ² / g or more and the positive electrode fiber is in close contact with other components in the positive electrode active material, lead It is considered that the positive electrode active material collapses and falls off from the current collector as the charge and discharge of the storage battery are repeated, and the life characteristics become low.

Further, in the samples S14 and S15 which do not satisfy the specific conditions for the separator because the compression ratio of the separator is less than 1.2, the evaluation of the life characteristics resulted in an extremely low value of 19 or less. In the samples S14 and S15, the compression ratio of the separator is excessively small. Therefore, in the samples S14 and S15, the thickness of the separator becomes thinner (that is, the thickness does not return to the initial thickness) as the electrode plate expands and contracts due to repeated charging and discharging. It is considered that the number of parts which can not be in contact with the electrode plate is increased to cause a capacity reduction, and the life characteristic is lowered.

Further, in the samples S20 and S21 which do not satisfy the specific conditions for the separator because the compression ratio of the separator exceeds 1.8, the evaluation of the life characteristics resulted in an extremely low value of “29” or less. In the samples S20 and S21, the compression ratio of the separator is excessively large. Therefore, in the samples S20 and S21, the chemical reaction performed during charge and discharge and the movement of the sulfate ion are blocked. That is, one of the functions of the separator is to hold sulfuric acid in the interstices of the fibers. However, when an excessive pressure is applied to the separator, the interstices inside the separator become too small, and the state of holding the sulfuric acid excessively decreases. It becomes. As a result, in the samples S20 and S21, it is considered that the capacity reduction occurs and the life characteristics become lower.

Thus, according to the present performance evaluation, the lead storage battery has the above-described specific condition (the condition that the compression ratio of the separator is 1.2 or more and 1.8 or less) related to the separator and the specific condition (the positive electrode active material) The total pore volume per unit mass of the substance is 0.150 cm ³ / g or less, the positive electrode active material contains a positive electrode fiber, and the positive electrode fiber by BET method using krypton gas as an adsorption gas on average specific surface area of satisfies both the conditions) that is 0.20 m 2 / ^g or more, effectively suppresses the dropping of the positive electrode active material from the positive electrode current collector (positive electrode material) in the positive electrode plate It has been confirmed that the life characteristics of lead acid batteries can be dramatically improved.

In addition, although not shown in the drawings, a negative electrode fiber in which an acrylic fiber having an average specific surface area of 0.20 m ² / g or more according to the BET method using krypton gas as adsorption gas is contained only in the negative electrode active material constituting the negative electrode plate The samples used as were not good for either the life or capacity characteristics. On the other hand, a negative electrode plate is also used as a positive electrode fiber in which an acrylic fiber having an average specific surface area of 0.20 m ² / g or more according to BET method using krypton gas as an adsorption gas is contained in a positive electrode active material constituting the positive electrode plate. In the sample used as the negative electrode fiber contained in the negative electrode active material constituting the above, the life characteristics and the capacity characteristics were equivalent to those of the samples S1 to S3, S6 to S12, and S16 to S19. According to this result, the life characteristics of the lead storage battery can be greatly improved by using a fiber having an average specific surface area of 0.20 m ² / g or more according to the BET method using krypton gas as adsorption gas as at least a fiber for a positive electrode. It can be said that it can be improved.

Of the samples S1 to S3, S6 to S12, and S16 to S19 of which good results were obtained in this performance evaluation, in the samples S6 to S12 and S16 to S19, the total pore volume per unit mass of the positive electrode active material Is 0.104 cm ³ / g or more and 0.150 cm ³ / g or less. In each of these samples, while a good result of “113” or more was obtained in the evaluation of the life characteristics, a good result of “96” or more was obtained in the evaluation of the capacitance characteristics. According to this result, in the lead storage battery, both of the specific conditions for the separator and the positive electrode active material described above are satisfied, and the total pore volume per unit mass of the positive electrode active material is 0.104 cm ³ / g If the above is 0.150 cm ³ / g or less, the total pore volume per unit mass of the positive electrode active material becomes excessively small, whereby the reactivity of the positive electrode active material becomes excessively low, and the capacity characteristic is lowered. While being hard to be influenced, it is possible to suppress that the density of the positive electrode active material becomes excessively low and the life characteristics deteriorate by the fact that the total pore volume per unit mass of the positive electrode active material becomes excessively large. I can say that. Therefore, in the lead-acid battery, both the specific conditions for the separator and the specific conditions for the positive electrode active material are satisfied, and the total pore volume per unit mass of the positive electrode active material is 0.104 cm ³ / g or more, 0.150 cm ³ It can be said that it is more preferable that it is / g or less. In the samples S6 to S12 and S16 to S19, the same life characteristics were obtained as compared with the samples S1 to S3 which are advantageous for the life characteristics because the total pore volume of the positive electrode active material is relatively small. Although the reason is not necessarily clear, samples S6 to S12 and S16 can be obtained by adopting fibers having an average specific surface area of 0.20 m ² / g or more according to the BET method using krypton gas as adsorption gas as fibers for a positive electrode. Even in the numerical range of the total pore volume of the positive electrode active material as in S19 to S19, it is possible to obtain the life characteristics equal to or more than the configuration in which the total pore volume of the positive electrode active material is smaller. It is.

Among the samples S6 to S12 and S16 to S19, in the samples S10 to S12, the total pore volume per unit mass of the positive electrode active material is 0.132 cm ³ / g or more and 0.150 cm ³ / g or less is there. In each of these samples, in the evaluation of the life characteristics, the results were more favorable than "135" or more, and in the evaluation of the capacitance characteristics, the results were extremely good as "112" or more. According to this result, in the lead storage battery, both of the specific conditions for the separator and the positive electrode active material described above are satisfied, and the total pore volume per unit mass of the positive electrode active material is 0.132 cm ³ / g If it is not less than 0.150 cm ³ / g, the decrease in reactivity of the positive electrode active material can be extremely effectively suppressed, so that the positive electrode active material (positive electrode material) from the positive electrode current collector in the positive electrode plate It can be said that the capacity characteristic of the lead storage battery can be extremely effectively improved while effectively suppressing the dropout. Therefore, in the lead-acid battery, both the specific conditions for the separator and the specific conditions for the positive electrode active material are satisfied, and the total pore volume per unit mass of the positive electrode active material is 0.132 cm ³ / g or more, 0.150 cm ³ It is more preferable that the ratio is / g or less.

In addition, in the samples S1 to S3, S6 to S12, and S16 to S19 for which good results were obtained in all the evaluation items, acrylic fibers were used as the positive electrode fibers. If an acrylic fiber is used as the positive electrode fiber, a fiber having an average specific surface area of 0.20 m ² / g or more according to the BET method using krypton gas as an adsorption gas can be easily obtained.

In the samples S1 to S3, S6 to S12, and S16 to S19, in which good results were obtained in all the evaluation items, acrylic fibers were used as fibers for the positive electrode, but other fibers (polypropylene based fibers) were used as fibers for the positive electrode. Even if fibers, polyester fibers, polyethylene fibers, PET fibers, rayon fibers) are used, if the positive electrode active material including the positive electrode fibers satisfies the specific conditions for the positive electrode active material described above, the positive electrode is similarly It is strongly speculated that the life characteristics of the lead-acid battery can be dramatically improved by effectively suppressing the dropout of the positive electrode active material (positive electrode material) from the positive electrode current collector in the plate.

B. Modification:
The technology disclosed in the present specification is not limited to the above-described embodiment, and can be modified into various forms without departing from the scope of the present invention. For example, the following modifications are also possible.

The configuration of the lead storage battery 100 in the above embodiment is merely an example, and various modifications are possible. For example, although acrylic fibers, polypropylene fibers, polyester fibers, polyethylene fibers, PET fibers, and rayon fibers are illustrated as the fibers 217 for the positive electrode in the above embodiment, the fibers 217 for the positive electrode are krypton Other types of fibers may be used as long as the average specific surface area according to the BET method using a gas as an adsorption gas is 0.20 m ² / g or more.

Further, in the lead storage battery 100 in the above-described embodiment, the negative electrode active material 226 constituting the negative electrode plate 220 may satisfy the same conditions as the specific conditions for the positive electrode active material described above.

Moreover, the manufacturing method of the lead storage battery 100 in the said embodiment is an example to the last, and can be variously deformed.

Reference Signs List 10: housing 12: battery case 14: lid 16: cell chamber 20: electrode plate group 30: positive electrode side terminal member 32: positive electrode side bushing 34: positive electrode column 36: positive electrode side terminal portion 40: negative electrode side terminal member 42: negative electrode Side bushing 44: Negative electrode post 46: Negative electrode side terminal portion 52: Positive electrode side strap 54: Negative electrode side strap 56: Connection member 58: Partition member 60: Control valve 70: Resin member 100: Lead storage battery 210: Positive electrode plate 212: Positive electrode current collector Body 214: positive electrode ear portion 216: positive electrode active material 217: fiber for positive electrode 220: negative electrode plate 222: negative electrode current collector 224: negative electrode ear portion 226: negative electrode active material 230: separator

Claims

Control valve type lead storage battery,
A positive electrode plate having a current collector and a positive electrode material supported by the current collector;
A negative electrode plate,
A separator, which is disposed between the positive electrode plate and the negative electrode plate and is made of glass fiber;
Equipped with
The compression ratio of the separator is 1.2 or more and 1.8 or less,
The total pore volume per unit mass of the positive electrode material is 0.150 cm 3 / g or less,
The positive electrode material contains a fiber,
The control valve-type lead acid battery whose average specific surface area of the said fiber by BET method which used krypton gas as adsorption gas is 0.20 m < 2 > / g or more.
It is a control valve type lead acid battery according to claim 1,
The control valve-type lead acid battery whose total pore volume per unit mass of the said positive electrode material is 0.104 cm < 3 > / g or more.
It is a control valve-type lead storage battery according to claim 2,
The control valve-type lead acid battery whose total pore volume per unit mass of the said positive electrode material is 0.132 cm < 3 > / g or more.
The valve-regulated lead-acid battery according to any one of claims 1 to 3, wherein
The valve-regulated lead-acid battery, wherein the fiber is an acrylic fiber.