JP2019071165A - Resin for lead storage battery, electrode, lead storage battery, and vehicle - Google Patents

Abstract

To provide a resin for a lead storage battery, having excellent charging acceptability in a lead storage battery.SOLUTION: A resin for a lead storage battery is a resin having a structural unit derived from a phenolic compound and contains a sulfonic acid potassium base.SELECTED DRAWING: None

Description

  The present invention relates to resins for lead storage batteries, electrodes, lead storage batteries and automobiles.

  Lead acid storage batteries for automobiles are widely used for engine start-up and power supply of electrical components. In recent years, an idling stop system (hereinafter referred to as "ISS") has begun to be implemented, which stops the engine at the time of temporary stop of the vehicle and restarts at the start as an effort of environmental protection and fuel efficiency improvement. In lead-acid batteries used in ISS, frequent repeated start and stop of the engine increases the number of times of large current discharge at the start of the engine, resulting in increased use of electrical components and increased discharge load.

Charging of automotive lead storage batteries is constant voltage charging with an alternator. In recent years, the set value of the alternator voltage has been lowered for the purpose of suppressing the decrease of the electrolyte solution due to water decomposition during charging. Also, in recent years, in addition to adopting such a low charging voltage, “charging by a running alternator, which is called a power generation control system, is controlled according to the traveling state of the vehicle and the charge state of the lead storage battery. The engine load is reduced to improve fuel efficiency and reduce CO ₂ emissions. In such a system, it is difficult for the lead storage battery to be charged, and it is difficult for the battery to be fully charged. Under such conditions of use, lead-acid batteries are not fully charged and are often used overdischarged.

  If the lead storage battery is not completely charged and the low charge state continues, a phenomenon (sulfation) may occur in which lead sulfate, which is an inactive discharge product, accumulates on the electrode (electrode plate or the like). In such a situation, it is known that battery performance such as charge acceptability declines because the electrode active material is in a state of being hard to be reduced (hard to be charged).

  In addition, when complete charging is difficult to be performed, a stratification phenomenon occurs in which a difference in concentration of dilute sulfuric acid, which is an electrolytic solution, occurs between the upper portion and the lower portion of an electrode (electrode plate or the like) in a lead storage battery. In this case, the concentration of the dilute sulfuric acid in the lower part of the electrode becomes high and sulfation occurs. Therefore, the reactivity of the lower part of the electrode is reduced, and only the upper part of the electrode is intensively reacted. As a result, deterioration such as weakening of bonding between electrode active materials progresses, and the electrode active material peels from the current collector (for example, current collector grid) supporting the electrode active material in the upper part of the electrode, and charge is received. Battery performance such as

  On the other hand, as a means for improving charge acceptance and the like, Patent Document 1 below discloses a technology relating to a negative electrode for a lead storage battery obtained using a negative electrode active material and a condensate of phenols, aminobenzene sulfonic acid and formaldehyde. Is disclosed.

WO 1997/37393

  By the way, there is a demand for lead storage batteries to further improve battery performance such as charge acceptance.

  This invention is made in view of the said situation, and it aims at providing resin for lead acid batteries which has the charge acceptance property excellent in lead acid batteries. Moreover, this invention aims at providing the electrode containing resin for said lead acid battery. Furthermore, the present invention aims to provide a lead-acid battery comprising the electrode. An object of the present invention is to provide an automobile provided with the lead storage battery.

  As a result of intensive studies by the present inventors, it has become clear that sufficient charge acceptance can not be obtained when the negative electrode for a lead-acid battery described in Patent Document 1 is used. On the other hand, the present inventors have found that the problem can be solved by using a resin having a structural unit derived from a phenolic compound and containing a potassium sulfonate base.

  That is, the resin for a lead storage battery according to the present invention is a resin having a structural unit derived from a phenolic compound, and contains a potassium sulfonate base.

  According to the resin for a lead storage battery of the present invention, it is possible to obtain excellent charge acceptance in a lead storage battery. Moreover, according to the resin for a lead storage battery of the present invention, battery performance such as excellent charge acceptance, discharge characteristics and cycle characteristics can be compatible.

  The structural unit may contain a structural unit derived from a bisphenol-based compound, and may contain a structural unit derived from lignin. In this case, the charge acceptance can be easily improved.

  When the resin for a lead storage battery according to the present invention has a structural unit derived from lignin, the weight average molecular weight of the resin is preferably 3000 to 50000.

  An electrode according to the present invention includes an electrode active material and a resin for a lead storage battery according to the present invention. The lead storage battery according to the present invention comprises the electrode according to the present invention. An automobile according to the present invention includes the lead storage battery according to the present invention. Also in these cases, excellent charge acceptance can be obtained.

  According to the present invention, it is possible to obtain excellent charge acceptance in a lead-acid battery. Moreover, according to the present invention, battery performance such as excellent charge acceptance, discharge characteristics and cycle characteristics can be compatible. According to the present invention, it is possible to provide a lead-acid battery that is sufficiently satisfactory as an ISS vehicle application used in a harsh environment. According to the present invention, an application of a lead storage battery to an ISS vehicle can be provided.

FIG. 1 is a perspective view showing an example of a lead storage battery. FIG. 2 is a view showing a part of the internal structure of the lead storage battery shown in FIG. FIG. 3 is a perspective view showing an example of an electrode plate group. It is a figure which shows the measurement result of < ¹ > H-NMR spectrum of bisphenol resin. It is a figure which shows the analytical curve in measurement of the weight average molecular weight of bisphenol-type resin.

  In the present specification, a numerical range indicated by using “to” indicates a range including numerical values described before and after “to” as the minimum value and the maximum value, respectively. The upper limit or lower limit of the numerical range of one step may be replaced with the upper limit or lower limit of the numerical range of another step in the numerical range described stepwise in the present specification. In the numerical range described in the present specification, the upper limit value or the lower limit value of the numerical range may be replaced with the value shown in the examples. “A or B” may contain either A or B, and may contain both. The materials exemplified herein can be used alone or in combination of two or more unless otherwise specified. In the present specification, the content of each component in the composition is the total amount of the plurality of substances present in the composition unless a plurality of substances corresponding to each component are present in the composition. Means

  Hereinafter, embodiments of the present invention will be described in detail.

<Resin for lead acid battery and its manufacturing method>
The resin for a lead storage battery according to the present embodiment is a resin having a structural unit derived from a phenolic compound, and contains a potassium salt of sulfonic acid. The sulfonic acid potassium base may be contained in the structural unit derived from the phenolic compound, and may be contained in the resin separately from the structural unit derived from the phenolic compound. The resin for a lead storage battery according to the present embodiment may have a structural unit derived from a phenolic compound and a structural unit having a potassium sulfonate base. Examples of the resin for a lead storage battery according to the present embodiment include bisphenol-based resins containing a potassium salt of sulfonic acid, and potassium lignin sulfonate (lignin sulfonic acid potassium salt). Hereinafter, in some cases, the resin for a lead storage battery according to the present embodiment will be referred to as “phenolic resin PR”.

(Bisphenol resin)
The resin for a lead storage battery according to the present embodiment may be a bisphenol-based resin containing a potassium salt of sulfonic acid. The bisphenol resin has a structural unit derived from a bisphenol compound as a structural unit derived from a phenol compound. The bisphenol resin containing a sulfonic acid potassium base is, for example, (a) a bisphenol compound (hereinafter, sometimes referred to as “component (a)”) and (b) a compound having a sulfo group (hereinafter, sometimes “(b And the component ()) can be obtained by replacing the hydrogen atom of the sulfo group with a potassium atom. In the reaction of the components (a) and (b), at least one selected from the group consisting of (c) formaldehyde and a formaldehyde derivative (hereinafter sometimes referred to as “component (c)”) may be further reacted.

  As the component (a), for example, 2,2-bis (4-hydroxyphenyl) propane (hereinafter referred to as “bisphenol A”), bis (4-hydroxyphenyl) methane, 1,1-bis (4-hydroxyphenyl) ) Ethane, 2,2-bis (4-hydroxyphenyl) hexafluoropropane, 1,1-bis (4-hydroxyphenyl) -1-phenylethane, 2,2-bis (4-hydroxyphenyl) butane, bis ( 4-hydroxyphenyl) diphenylmethane, 1,1-bis (4-hydroxyphenyl) cyclohexane, 1,1-bis (4-hydroxyphenyl) -3,3,5-trimethylcyclohexane, and bis (4-hydroxyphenyl) Sulfone (hereinafter referred to as "bisphenol S") can be mentioned. The component (a) can be used alone or in combination of two or more. As the component (a), bisphenol A is preferable from the viewpoint of further excellent charge acceptance, and bisphenol S is preferable from the viewpoint of further excellent discharge characteristics.

  As the component (a), it is preferable to use bisphenol A and bisphenol S in combination from the viewpoint of improving charge acceptance, discharge characteristics and cycle characteristics in a well-balanced manner. In this case, the content of bisphenol A in the reaction for obtaining the bisphenol resin is 70 moles based on the total amount of bisphenol A and bisphenol S from the viewpoint of improving charge acceptance, discharge characteristics and cycle characteristics in a well-balanced manner. % Or more is preferable, 75 mol% or more is more preferable, and 80 mol% or more is still more preferable. The content of bisphenol A is preferably 99 mol% or less, more preferably 98 mol% or less, based on the total amount of bisphenol A and bisphenol S, from the viewpoint of improving charge acceptance, discharge characteristics and cycle characteristics in a well-balanced manner. And 97 mol% or less is more preferable.

  As the component (b), a compound having an amino group and a sulfo group can be used. Examples of compounds having an amino group and a sulfo group include 4-aminobenzenesulfonic acid (also referred to as sulfanilic acid), aminoethylsulfonic acid (also referred to as taurine), and 5-amino-1-naphthalenesulfonic acid (also referred to as laurent acid). Can be mentioned.

  The component (b) can be used alone or in combination of two or more. As a component (b), 4-aminobenzenesulfonic acid is preferable from the viewpoint of further improving charge acceptance.

  From the viewpoint of further improving the discharge characteristics, the content of the component (b) in the reaction for obtaining a bisphenol resin is preferably 0.5 mol or more, preferably 0.6 mol or more, per 1 mol of the component (a). Is more preferable, 0.7 mol or more is more preferable, and 0.8 mol or more is particularly preferable. The content of the component (b) is preferably 2.0 mol or less, more preferably 1.5 mol or less, per 1 mol of the component (a), from the viewpoint of facilitating further improvement of the discharge characteristics and cycle characteristics. .3 mol or less is more preferable, and 1.0 mol or less is particularly preferable.

  As formaldehyde which is the component (c), formaldehyde in formalin (for example, an aqueous solution of 37% by mass of formaldehyde) may be used. Examples of formaldehyde derivatives include paraformaldehyde, hexamethylenetetramine and trioxane. The component (c) can be used alone or in combination of two or more. Formaldehyde and a formaldehyde derivative may be used in combination.

From the viewpoint of easily obtaining excellent cycle characteristics, the component (c) is preferably a formaldehyde derivative, and more preferably paraformaldehyde. Paraformaldehyde has, for example, a structure represented by the following general formula (1).
HO (CH ₂ O) _{n 1} H (1)
[In Formula (1), n1 shows the integer of 2-100. ]

  From the viewpoint of improving the reactivity of the component (b), the compounding amount of the component (c) in the reaction for obtaining a bisphenol resin is preferably 2 moles or more with respect to 1 mole of the component (a), 2.2 mol or more is more preferable, and 2.4 mol or more is further preferable. The compounding amount of the component (c) in terms of formaldehyde is obtained by the reaction of the components (a), (b) and (c) and from the viewpoint of easily reducing the structural unit having a benzoxazine ring, the component (a) 3.5 mol or less is preferable with respect to 1 mol, 3.2 mol or less is more preferable, 3 mol or less is more preferable, less than 2.8 mol is especially preferable, and 2.5 mol or less is very preferable.

  The bisphenol resin preferably has, for example, at least one of a structural unit represented by the following general formula (I) and a structural unit represented by the following general formula (II).

[In formula (I), X ¹ represents a divalent group, Y ¹ represents an aromatic hydrocarbon, an aliphatic hydrocarbon or an alicyclic hydrocarbon, and R ¹¹ , R ¹² and R ¹³ represent Each independently represents a potassium atom or a hydrogen atom, n11 represents an integer of 1 to 300, and n12 represents an integer of 1 to 3. Moreover, the hydrogen atom directly bonded to the carbon atom which comprises a benzene ring may be substituted by the C1-C5 alkyl group. ]

[In Formula (II), X ² represents a divalent group, Y ² represents an aromatic hydrocarbon, an aliphatic hydrocarbon or an alicyclic hydrocarbon, and R ²¹ , R ²² and R ^{23 each} represent Each independently represents a potassium atom or a hydrogen atom, n21 represents an integer of 1 to 300, and n22 represents an integer of 1 to 3. Moreover, the hydrogen atom directly bonded to the carbon atom which comprises a benzene ring may be substituted by the C1-C5 alkyl group. ]

  The ratio of the structural unit represented by the formula (I) and the structural unit represented by the formula (II) is not particularly limited, and may vary depending on synthesis conditions and the like. As a bisphenol resin, you may use resin which has only any one of the structural unit represented by Formula (I), and the structural unit represented by Formula (II).

As X ^a and X ^b , an alkylidene group (for example, methylidene group, ethylidene group, isopropylidene group and sec-butylidene group), a cycloalkylidene group (for example, cyclohexylidene group), a phenyl alkylidene group (for example, diphenylmethylidene group and phenyl) Organic groups such as ethylidene group); sulfonyl group etc. may be mentioned. As X ^a and X ^b , an isopropylidene group (-C (CH ₃ ) _2- ) group is preferable from the viewpoint of further excellent charge acceptance, and a sulfonyl group (-SO _2- ) from the viewpoint of further excellent discharge characteristics. Is preferred. X ^a and X ^b may be substituted by a halogen atom such as a fluorine atom. When X ^a or X ^b is a cycloalkylidene group, the hydrocarbon ring may be substituted by an alkyl group or the like.

Examples of Y ¹ and Y ² include aromatic hydrocarbons (eg, phenylene group and naphthylene group), aliphatic hydrocarbons (eg, ethylene group and trimethylene group), alicyclic hydrocarbons (eg, cyclohexylidene group), etc. . As Y ¹ and Y ² , a phenylene group or a naphthylene group is preferable from the viewpoint of further excellent charge acceptance. Y ¹ and Y ² may be substituted by a halogen atom such as a fluorine atom.

  The bisphenol resin may have, for example, structural units represented by the following general formulas (III) to (VI). The reason why the structural units represented by the formulas (III) to (VI) are formed is presumed to be that the formaldehyde component causes an addition reaction to the benzene ring of the component (a).

X ³ , X ⁴ , X ⁵ and X ^{6 each} represent a divalent group, and R ³¹ , R ³² , R ³³ , R ⁴¹ , R ⁴² , R ⁴³ , R ⁵¹ , R ⁵² , R ⁶¹ and R ^{62 each} represent And each independently represents a potassium atom or a hydrogen atom, n31, n41, n51 and n61 each represents an integer of 1 to 300, and n32 and n42 each represent an integer of 1 to 3. Moreover, the hydrogen atom directly bonded to the carbon atom which comprises a benzene ring may be substituted by the C1-C5 alkyl group.

  From the viewpoint of further improving the cycle characteristics, the weight average molecular weight of the bisphenol resin is preferably 20000 or more, more preferably 30000 or more, still more preferably 40000 or more, and particularly preferably 50000 or more. From the viewpoint of further improving the cycle characteristics, the weight average molecular weight of the bisphenol resin is preferably 80,000 or less, more preferably 70,000 or less, and still more preferably 60000 or less. From these viewpoints, the weight average molecular weight of the bisphenol-based resin is preferably 20000 to 80000, more preferably 30000 to 70000, still more preferably 40000 to 60000, and particularly preferably 50000 to 60000.

The weight average molecular weight of the bisphenol resin can be measured, for example, by gel permeation chromatography (hereinafter referred to as "GPC") under the following conditions.
(GPC conditions)
Device: High-performance liquid chromatograph LC-2200 Plus (manufactured by JASCO Corporation)
Pump: PU-2080
Differential Refractometer: RI-2031
Detector: UV-visible spectrophotometer UV-2075 (λ: 254 nm)
Column oven: CO-2065
Column: TSKgel SuperAW (4000), TSKgel SuperAW (3000), TSKgel SuperAW (2500) (manufactured by Tosoh Corporation)
Column temperature: 40 ° C
Eluent: methanol solution containing LiBr (10 mM) and triethylamine (200 mM) Flow rate: 0.6 mL / min Molecular weight standard sample: polyethylene glycol (molecular weight: 1.10 × 10 ⁶ , 5.80 × 10 ⁵ , 2.55 × 10 ⁵ , 1.46 × 10 ⁵ , 1.01 × 10 ⁵ , 4.49 × 10 ⁴ , 2.70 × 10 ⁴ , 2.10 × 10 ⁴ ; manufactured by Tosoh Corporation, diethylene glycol (molecular weight: 1 .06 × 10 ² ; manufactured by Kishida Chemical Co., Ltd., dibutylhydroxytoluene (molecular weight: 2.20 × 10 ² ; manufactured by Kishida Chemical Co., Ltd.)

  The method for producing a bisphenol-based resin includes, for example, a resin-producing step of reacting a component (a), a component (b) and a component (c) to obtain a bisphenol-based resin. The bisphenol resin can be obtained, for example, by reacting component (a), component (b) and component (c) in a reaction solvent. The reaction solvent is preferably water (for example, ion exchanged water). An organic solvent, a catalyst, an additive and the like may be used to accelerate the reaction.

  In the resin production process, the compounding amount of the component (b) is 0.5 to 2.0 mol with respect to 1 mol of the component (a) from the viewpoint of further improving the cycle characteristics, and the compounding of the component (c) An embodiment in which the amount is 2 to 3.5 moles in terms of formaldehyde relative to 1 mole of the component (a) is preferable, and the blending amount of the component (b) is 0.5 to 2.0 per 1 mole of the component (a) More preferable is an embodiment in which the amount of component (c) is 2 to 2.5 moles in terms of formaldehyde relative to 1 mole of component (a). The preferable blending amounts of the components (b) and (c) are the ranges described above for the blending amounts of the components (b) and (c).

  The bisphenol resin is preferably obtained by reacting the components (a), (b) and (c) under basic conditions (alkaline conditions) from the viewpoint that a sufficient amount of the bisphenol resin is easily obtained. A basic compound may be used to adjust to basic conditions. Examples of the basic compound include potassium hydroxide and potassium carbonate. The basic compounds can be used alone or in combination of two or more. Among the basic compounds, potassium hydroxide is preferable from the viewpoint of excellent reactivity.

  When the reaction solution at the time of reaction is neutral (pH = 7), the reaction for producing a bisphenol resin may not progress easily, and when the reaction solution is acidic (pH <7), side reactions (eg, benzo In some cases, the reaction of producing a structural unit having an oxazine ring may proceed. Therefore, the pH of the reaction solution at the time of reaction is preferably alkaline (more than 7) from the viewpoint of easily suppressing the progress of the side reaction while advancing the formation reaction of the bisphenol resin. Is more preferable, and 7.2 or more is further preferable. The pH of the reaction solution is preferably 12 or less, more preferably 10 or less, and still more preferably 9 or less, from the viewpoint of suppressing the progress of hydrolysis of the group derived from the component (b) in the bisphenol resin. The pH of the reaction solution can be measured, for example, by Twin pH Meter AS-212 manufactured by Horiba, Ltd. The pH is defined as the pH at 25 ° C.

  The amount of the strongly basic compound added is preferably 1.01 mol or more, more preferably 1.02 mol or more, per 1 mol of the component (b) since it is easy to adjust to the pH as described above. More than 03 mol is more preferred. From the same viewpoint, the blending amount of the strongly basic compound is preferably 1.1 mol or less, more preferably 1.08 mol or less, and still more preferably 1.07 mol or less, per 1 mol of the component (b). Examples of strongly basic compounds include potassium hydroxide and potassium carbonate.

  In this embodiment, a reactant (reaction solution) obtained by the method for producing a bisphenol-based resin may be used as it is for producing an electrode described later, or a bisphenol-based resin obtained by drying the reactant can be used as a solvent (water, etc. ), And may be used for the production of an electrode described later.

  The synthesis reaction of the bisphenol-based resin may be such that the (a) component, the (b) component and the (c) component react to obtain the bisphenol-based resin, for example, the (a) component, the (b) component and the (c) The components may be reacted simultaneously, or after the two components of the components (a), (b) and (c) are reacted, the remaining one component may be reacted.

  The synthesis reaction of the bisphenol resin is preferably performed in two steps as follows. In the first step reaction, for example, after charging the component (b), the solvent (such as water) and the basic compound, stirring is performed, and the hydrogen atom of the sulfo group in the component (b) is substituted by a potassium atom (b) Obtain the potassium salt of the component. This makes it easy to suppress side reactions in the condensation reaction described later. The temperature of the reaction system is preferably 0 ° C. or more, more preferably 25 ° C. or more, from the viewpoint of excellent solubility of the component (b) in a solvent (such as water). The temperature of the reaction system is preferably 80 ° C. or less, more preferably 70 ° C. or less, and still more preferably 65 ° C. or less from the viewpoint of easily suppressing the side reaction. The reaction time is, for example, 30 minutes.

  In the reaction of the second step, for example, the component (a) and the component (c) are added to the reaction product obtained in the first step to cause a condensation reaction to obtain a bisphenol resin. The temperature of the reaction system is preferably 75 ° C. or higher, and 85 ° C. or higher, from the viewpoint of excellent reactivity of the components (a), (b) and (c) and from the viewpoint of reduction of side reaction products. The temperature is more preferably 92 ° C. or more. The temperature of the reaction system is preferably 100 ° C. or less, more preferably 98 ° C. or less, and still more preferably 96 ° C. or less from the viewpoint of easily suppressing side reactions. The reaction time is, for example, 5 to 20 hours.

(Lignin potassium sulfonate)
The resin for a lead acid battery according to the present embodiment may be potassium lignin sulfonate. Potassium lignin sulfonate is a potassium salt of lignin sulfonic acid in which a part of lignin degradation product is sulfonated. Potassium lignin sulfonate has a structural unit derived from lignin as a structural unit derived from a phenolic compound. In addition, potassium lignin sulfonate contains a sulfonate potassium base.

  Potassium lignin sulfonate can be obtained by substituting sodium atom of sodium lignin sulfonate with potassium atom. For example, potassium lignin sulfonate can be obtained by neutralizing a black liquor remaining after digesting wood chips and taking out cellulose with potassium hydroxide or the like. In addition, potassium lignin sulfonate can be obtained by dialysis after obtaining sodium lignin sulfonate and subsequent neutralization with potassium hydroxide.

  Lignin sulfonate sodium can be obtained by neutralizing the black liquor remaining after the wood chips are digested to take out the cellulose with sodium hydroxide, calcium hydroxide, magnesium hydroxide or the like. The structure of sodium lignin sulfonate can have a structural unit represented by the following general formula (2).

[In Formula (2), n2 shows an integer greater than or equal to one. ]

  The weight-average molecular weight of potassium lignin sulfonate is preferably 3000 or more, more preferably 7,000 or more, from the viewpoint of further suppressing the elution of potassium lignin sulfonate from the electrode to the electrolyte in the lead storage battery and obtaining further excellent cycle characteristics. Preferably, 8000 or more is more preferable. From the viewpoint of excellent dispersibility of the electrode active material, the weight average molecular weight of potassium lignin sulfonate is preferably 50,000 or less, more preferably 30,000 or less, and still more preferably 20,000 or less. From these viewpoints, the weight average molecular weight of potassium lignin sulfonate is preferably 3,000 to 50,000, more preferably 7,000 to 30,000, and still more preferably 8,000 to 20,000. The weight average molecular weight of potassium lignin sulfonate can be measured by the same method as the weight average molecular weight of the bisphenol resin.

  0.01-2 mass% is preferable on the basis of the total mass of an electrode active material, and, as for content of phenol resin PR in an electrode layer, 0.05-1 mass% is more preferable, and 0.1-0.5. % By mass is more preferred.

<Resin composition>
The resin composition according to the present embodiment contains the resin for a lead storage battery according to the present embodiment. The resin composition according to the present embodiment may contain a solvent. As the solvent, for example, water (for example, ion exchanged water) and an organic solvent can be mentioned. The solvent contained in the resin composition may be the reaction solvent used to obtain the bisphenol resin. The resin composition according to the present embodiment may further contain a natural resin or synthetic resin other than the phenolic resin PR.

  The resin composition according to the present embodiment may be a composition obtained in the resin production process, and is a composition obtained by mixing the phenolic resin PR with other components after obtaining the phenolic resin PR. It may be.

  The content of the phenolic resin PR in the resin composition according to the present embodiment is 70 mass based on the total mass of the nonvolatile matter in the resin composition from the viewpoint of improving charge acceptance, discharge characteristics and cycle characteristics in a well-balanced manner. % Or more is preferable, 80 mass% or more is more preferable, 90 mass% or more is still more preferable.

  In the resin composition according to the present embodiment, the content (total amount) of the structural units represented by the formulas (III) to (VI) is more excellent in storage stability of the resin composition and cycle characteristics. Therefore, 0.55 mass% or less is preferable on the basis of the total mass of the non volatile matter in a resin composition, 0.50 mass% or less is more preferable, 0.45 mass% or less is still more preferable. The structural units represented by the formulas (III) to (VI) may cause a decrease in storage stability because the molecular weight is increased by condensation polymerization of the methylol group.

The measurement of the non-volatile content in the resin composition can be measured, for example, by the following procedure. First, a predetermined amount (for example, 2 g) of the resin composition is placed in a container (for example, a metal petri dish such as a stainless steel petri dish), and then the resin composition is dried at 150 ° C. for 60 minutes using a hot air drier. Next, after the temperature of the container returns to room temperature (for example, 25 ° C.), the residual mass is measured. Then, the non-volatile content is calculated from the following equation.
Nonvolatile content (mass%) = [(mass of residue after drying) / (mass of resin composition before drying)] × 100

  7. The pH of the resin composition (for example, a resin solution liquid at 25 ° C.) is preferably alkaline (above 7) from the viewpoint of excellent solubility of the phenolic resin PR in a solvent (such as water); 1 or more is more preferable. From the viewpoint of further improving the storage stability of the resin composition, the pH of the resin composition is preferably 10 or less, more preferably 9 or less, and still more preferably 8.5 or less. When using the composition obtained in a resin manufacturing process especially as a resin composition, it is preferable that pH of a resin composition is the said range. The pH of the resin composition can be measured, for example, by Twin pH meter AS-212 manufactured by HORIBA, Ltd. The pH is defined as the pH at 25 ° C.

<Electrode, lead storage battery and manufacturing method of these>
The electrode according to the present embodiment is manufactured using a phenolic resin PR, and includes an electrode active material and a phenolic resin PR. Moreover, the electrode which concerns on this embodiment may be manufactured using the resin composition containing phenolic resin PR.

  In the case where the electrode is unformed, the electrode includes, for example, an electrode layer containing a raw material of an electrode active material (a negative electrode active material or a positive electrode active material), and a current collector supporting the electrode layer. The electrode after formation includes, for example, an electrode layer including an electrode active material (a negative electrode active material or a positive electrode active material) and the like, and a current collector supporting the electrode layer. The electrode is, for example, a negative electrode (lead plate etc.) for lead storage battery.

  The negative electrode active material can be obtained by forming an unformed negative electrode active material after obtaining an unformed negative electrode active material by maturing and drying a negative electrode paste containing a raw material of the negative electrode active material. It is preferable that the negative electrode active material after formation contains porous sponge lead. The positive electrode active material can be obtained by forming an unformed positive electrode active material after obtaining an unformed positive electrode active material by maturing and drying a positive electrode paste containing a raw material of the positive electrode active material. The positive electrode active material after formation contains, for example, lead dioxide.

  The lead storage battery according to the present embodiment includes the electrode according to the present embodiment. Examples of the lead storage battery according to the present embodiment include a liquid lead storage battery and a sealed lead storage battery, and a liquid lead storage battery is preferable.

  FIG. 1 is a perspective view showing an example of a lead storage battery. The lead storage battery 1 shown in FIG. 1 is a liquid lead storage battery. FIG. 2 is a view showing a part of the internal structure of the lead storage battery 1. The lead storage battery 1 includes a battery case 2 in which the upper surface is opened and the plurality of electrode plate groups 11 are stored, and a lid 3 for closing the opening of the battery case 2. The lid 3 includes, for example, a positive electrode terminal 4, a negative electrode terminal 5, and a liquid plug 6 for closing a liquid injection port provided in the lid 3. An electrolytic solution (not shown) is accommodated in the battery case 2.

  The electrode plate group includes a separator and a positive electrode plate and a negative electrode plate alternately stacked via the separator. FIG. 3 is a perspective view showing an example of an electrode plate group. As shown in FIGS. 2 and 3, the electrode plate group 11 includes, for example, a positive electrode plate 12, a negative electrode plate 13, a bag-like separator 14, a positive side strap 15, a negative side strap 16, and intercell connection A portion 17 and a pole post 18 are provided. At the upper peripheral edge portions of the positive electrode plate 12 and the negative electrode plate 13, a current collecting portion 22 and a current collecting portion 32 called an ear portion are provided.

  The method of manufacturing a lead storage battery according to the present embodiment includes, for example, an electrode manufacturing step of obtaining an electrode using a phenolic resin PR, and an assembly step of assembling a component including the electrode to obtain a lead storage battery.

  In the electrode manufacturing process, for example, after an electrode paste is filled in a current collector (for example, a current collector grid), aging and drying are performed to obtain an unformed electrode. The electrode paste contains, for example, a raw material of an electrode active material and a phenolic resin PR, and may further contain other predetermined additives and the like. When the electrode is a negative electrode, the raw material of the negative electrode active material is preferably a lead powder (for example, a mixture of a powder of PbO and a flaky metallic lead). The average particle diameter of the raw material of the negative electrode active material is preferably 1 to 5 μm from the viewpoint of further excellent charge acceptance and discharge characteristics. Examples of the additive include barium sulfate, a carbon material, and reinforcing staple fibers (acrylic fiber, polyethylene fiber, polypropylene fiber, polyethylene terephthalate fiber, carbon fiber, etc.). Examples of the carbon material include carbon black and graphite. Examples of carbon black include furnace black, channel black, acetylene black, thermal black and ketjen black.

  When the electrode according to the present embodiment is a negative electrode, a negative electrode paste can be obtained, for example, by the following method. First, a mixture is obtained by mixing, with lead powder, a phenolic resin PR and an additive that is optionally added. Next, a diluted sulfuric acid and a solvent (such as water) are added to this mixture and kneaded to obtain a negative electrode paste.

  In the case of using barium sulfate, a carbon material, or a phenolic resin PR in the negative electrode paste, the content of each component is preferably in the following range. As for content of barium sulfate, 0.01-1 mass% is preferable on the basis of the total mass of the raw materials (lead powder etc.) of a negative electrode active material. As for content of a carbon material, 0.2-1.4 mass% is preferable on the basis of the total mass of the raw materials (lead powder etc.) of a negative electrode active material. The content of the phenolic resin PR is preferably 0.01 to 2% by mass, and 0.05 to 1% by mass in terms of resin solid content, based on the total mass of the raw material (lead powder etc.) of the negative electrode active material. More preferably, 0.1 to 0.5% by mass is more preferable.

  Examples of the material of the current collector include lead alloys such as lead-calcium-tin alloys and lead-antimony-arsenic alloys. Selenium, silver, bismuth or the like may be appropriately added to the current collector depending on the application. A current collector can be obtained by forming these lead alloys in a grid shape by a gravity casting method, an expanding method, a punching method or the like.

  As ripening conditions, a temperature of 35 to 85 ° C. and a humidity of 50 to 98 RH% are preferable for 15 to 60 hours. The drying conditions are preferably 45 to 80 ° C. and 15 to 30 hours.

The positive electrode (positive electrode plate etc.) for lead storage batteries can be obtained, for example, by the following method. First, reinforcing short fibers are added to lead powder (PbO) which is a raw material of an electrode active material, and then water and dilute sulfuric acid are added. The mixture is kneaded to prepare a positive electrode paste. When producing the positive electrode paste, from the viewpoint of shortening the formation time, red lead (Pb ₃ O ₄ ) may be added. The positive electrode paste is filled in a current collector (current collector grid or the like), followed by aging and drying to obtain an unformed positive electrode. In the positive electrode paste, the content of reinforcing short fibers is preferably 0.005 to 0.3% by mass based on the total mass of the raw material (lead powder etc.) of the positive electrode active material. The type of current collector, the aging conditions and the drying conditions are almost the same as in the case of the negative electrode.

  In the assembly process, for example, the unformed negative electrode and positive electrode fabricated as described above are alternately stacked via a separator, and electrodes of the same polarity (electrode plate etc.) are connected with a strap (welding etc.) Obtain a group (plate group etc.). This electrode group is disposed in a battery case to produce an unformed battery. Next, after pouring dilute sulfuric acid into an unformed battery, a direct current is applied to form a battery, thereby obtaining a lead storage battery. Alternatively, after removing the dilute sulfuric acid once, an electrolytic solution (diluted sulfuric acid) may be injected. The specific gravity (in terms of 20 ° C.) of the electrolytic solution (diluted sulfuric acid) is preferably 1.25 to 1.35.

  Examples of the material of the separator include polyethylene and glass fiber. The chemical conversion conditions and the specific gravity of the electrolytic solution (diluted sulfuric acid) can be adjusted according to the properties of the electrode active material, the size of the electrode, and the like. In addition, the chemical conversion treatment is not limited to being performed in the assembly process, and may be performed in the electrode manufacturing process.

<Cars>
The vehicle according to the present embodiment includes the lead storage battery according to the present embodiment. Examples of the vehicle according to the present embodiment include an ISS vehicle.

  Hereinafter, the present invention will be specifically described by way of examples. However, the present invention is not limited to the following examples.

<Experiment A>
(Synthesis of bisphenol resin)
Example A1
The following components were charged in a reaction vessel equipped with a stirring device, a refluxing device, and a temperature control device to obtain a first mixed liquid.
Potassium hydroxide: 0.92 mol [51.6 parts by mass]
Ion-exchanged water: 51.3 moles [923.6 parts by mass]
4-aminobenzenesulfonic acid: 0.80 mol [136.6 parts by mass]

The first mixture was mixed and stirred at 25 ° C. for 30 minutes. Subsequently, the following components were added to the first mixed solution to obtain a second mixed solution.
Bisphenol A: 0.90 mol [205.5 parts by mass]
Bisphenol S: 0.10 mol [26.0 parts by mass]
Paraformaldehyde (Mitsui Chemical Co., Ltd.): 2.25 moles [68.2 parts by mass] (formaldehyde conversion)

The second mixed solution (pH = 8.6) was reacted at 95 ° C. for 10 hours to obtain a resin solution. The obtained aqueous solution was transferred to a heat-resistant container, and then charged into a vacuum dryer set at 60 ° C. The resin powder (bisphenol resin) was obtained by drying for 10 hours under a reduced pressure of 1 kPa or less. The ¹ H-NMR spectrum of the bisphenol resin obtained in Example A1 was measured under the following conditions. The measurement results of the ¹ H-NMR spectrum are shown in FIG.

{NMR conditions}
Device: AV400M (made by Bruker Biospin Co., Ltd.)
Measurement temperature: room temperature (25 ° C)
Measurement solvent: DMSO-d6 (manufactured by Wako Pure Chemical Industries, Ltd.)

[Example A2, Comparative Examples A1 to A3]
Bisphenol-based resins of Example A2 and Comparative Examples A1 to A3 were obtained by the same method as Example A1, except that the components of the resin composition were changed to the components in Table 1.

(Evaluation of bisphenol resin)
[Measurement of potassium content]
The potassium content in the isolated bisphenol-based resin was calculated from the ratio of the amount of potassium to the mass of the resin to be measured in ICP analysis. The ICP analysis conditions are as follows. The results are shown in Table 1.

{ICP analysis conditions}
Device: optima 4300DV (made by Perkin Elemer)
Argon flow rate: 0.65 L / min Standard sample: Potassium chloride standard solution (Kanto Chemical Co., Ltd.)

[Measurement of weight average molecular weight]
The weight average molecular weight of the isolated bisphenol resin was measured by GPC under the following conditions. The results are shown in Table 1.

{GPC conditions}
Device: High-performance liquid chromatograph LC-2200 Plus (manufactured by JASCO Corporation)
Pump: PU-2080
Differential Refractometer: RI-2031
Detector: UV-visible spectrophotometer UV-2075 (λ: 254 nm)
Column oven: CO-2065
Column: TSKgel SuperAW (4000), TSKgel SuperAW (3000), TSKgel SuperAW (2500) (manufactured by Tosoh Corporation)
Column temperature: 40 ° C
Eluent: methanol solution containing LiBr (10 mM) and triethylamine (200 mM) Flow rate: 0.6 mL / min Molecular weight standard sample: polyethylene glycol (molecular weight: 1.10 × 10 ⁶ , 5.80 × 10 ⁵ , 2.55 × 10 ⁵ , 1.46 × 10 ⁵ , 1.01 × 10 ⁵ , 4.49 × 10 ⁴ , 2.70 × 10 ⁴ , 2.10 × 10 ⁴ ; manufactured by Tosoh Corporation, diethylene glycol (molecular weight: 1 .06 × 10 ² ; manufactured by Kishida Chemical Co., Ltd., dibutylhydroxytoluene (molecular weight: 2.20 × 10 ² ; manufactured by Kishida Chemical Co., Ltd.)

  The calibration curve calculated from the standard sample is shown in FIG. The horizontal axis is the retention time, and the vertical axis is the logarithm of molecular weight.

(Fabrication of negative electrode plate)
0.2% by mass, 0.2% by mass of furnace black, and 1.0% by mass of barium sulfate were added to lead powder (average particle diameter 2 μm) in a dry state after solid content conversion of the resin solution ( Formulation criteria: Total mass of lead powder). Next, it knead | mixed, adding dilute sulfuric acid (specific gravity 1.26 (20 degreeC conversion)) and water, and the negative electrode paste was produced. The negative electrode paste was filled in an expanded current collector (lead-calcium-tin alloy) having a thickness of 0.6 mm to prepare a negative electrode plate. After allowing the negative electrode plate to stand for 18 hours under the atmosphere of a temperature of 50 ° C. and a humidity of 95% for aging according to a usual method, it was dried under the atmosphere of a temperature of 50 ° C. to obtain an unformed negative electrode plate.

(Production of positive plate)
0.01% by mass (standard: total mass of lead powder) reinforcing short fibers (polyethylene fibers) were added to lead powder (average particle diameter 2 μm) and then dry mixed. Next, diluted sulfuric acid (specific gravity 1.26 (converted to 20 ° C.)) and water were added and kneaded to prepare a positive electrode paste. A positive electrode current collector (lead-calcium-tin alloy) consisting of a casting grid is filled with a positive electrode paste, and left for aging for 18 hours under the atmosphere of temperature 50 ° C. and humidity 95% for aging. It dried under the atmosphere of ° C and obtained an unformed positive electrode plate.

(Assembly of battery)
The unformed negative electrode plate was inserted into the polyethylene separator processed into a bag shape. Next, six unformed negative electrode plates and five unformed positive electrode plates are formed so that the unformed positive electrode plate and the unformed negative electrode plate inserted in the bag-like separator are alternately laminated. Stacked. Subsequently, the ears of the electrode plates of the same polarity were welded together by a cast-on-strap (COS) method to produce an electrode group. The electrode group was inserted into the battery case to assemble a 2 V single cell battery. Diluted sulfuric acid (specific gravity 1.28 (20 ° C. conversion)) was poured into this battery, and then formed in a 50 ° C. water tank at a current of 10 A for 16 hours to obtain a lead storage battery.

(Evaluation of battery characteristics)
The charge acceptance, discharge characteristics and cycle characteristics of the 2 V single cell battery were measured as follows. The measurement results of the charge acceptance, the discharge characteristic and the cycle characteristic of Comparative Example A1 were each set to 100, and each characteristic was relatively evaluated. The results are shown in Table 1.

[Charge Acceptability]
As the charge acceptability, the state of charge (state of charge) of the battery is 90% (that is, in the state of discharging 10% of the battery capacity from the fully charged state at the 5-hour rate current value to the rated capacity) The constant voltage charging was performed at 25 ° C. and 2.333 V, and the current value 5 seconds after the start of charging was measured. The larger the current value after 5 seconds, the higher the initial charge capacity and the higher the charge acceptance.

[Discharge characteristics]
As discharge characteristics, a fully charged battery kept for at least 16 hours in an atmosphere of -15 ° C is discharged at constant current at 5 C under room temperature (25 ° C), and a discharge duration time until the battery voltage reaches 1.0 V Was measured. It is evaluated that the battery is excellent in discharge characteristics as the discharge duration time is longer. In addition, said C represents the magnitude | size of the electric current at the time of carrying out constant current discharge of a rated capacity from a full charge state relatively. The C means "discharge current value (A) / battery capacity (Ah)". For example, a current capable of discharging the rated capacity in one hour is expressed as “1 C”, and a current capable of discharging in two hours is expressed as “0.5 C”.

[Cycle characteristics]
The cycle characteristics were evaluated by a method according to a light load life test (JIS D 5301) of Japanese Industrial Standard. The larger the cycle number, the higher the durability of the battery.

<Experiment B>
(Preparation of lignin sulfonate)
Example B1
Sodium lignin sulfonate (trade name: Vanillex N, manufactured by Nippon Paper Industries Co., Ltd.) was dissolved in water to obtain an aqueous solution. The aqueous solution is injected into a dialysis tube (Biotech CE dialysis tube manufactured by Funakoshi Co., Ltd.), and dialysis is performed for 12 hours against 5 liters of ultrapure water collected from a pure water production apparatus (Millipore manufactured by DirectQ-UV) Repeated 5 times. Next, using a potentiometric automatic titrator (manufactured by Kyoto Denshi Kogyo Co., Ltd., AT-610), an aqueous solution of potassium hydroxide was dropped to the equivalent point to obtain an aqueous solution of potassium lignin sulfonate by neutralization. The aqueous solution of potassium lignin sulfonate was subjected to drying under reduced pressure to obtain powdered potassium lignin sulfonate. The potassium content and weight average molecular weight of potassium lignin sulfonate were measured by the same method as in Experiment A. The results are shown in Table 2.

[Examples B2 and B3]
Powdered potassium lignin sulfonate was obtained in the same manner as in Example B1, except that the concentration of the aqueous potassium hydroxide solution used for neutralization was changed. Further, in the same manner as in Example B1, the potassium content and weight average molecular weight of the powdered potassium lignin sulfonate were measured. The results are shown in Table 2.

Comparative Example B1
Sodium lignin sulfonate (manufactured by Nippon Paper Industries Co., Ltd., trade name: Vanillex N) was prepared as a lignin sulfonate. The results of measuring the weight average molecular weight of sodium lignin sulfonate in the same manner as in Example B1 are shown in Table 2. Further, in ICP analysis, the sodium content was calculated from the ratio of the amount of sodium to the mass of the resin to be measured. The ICP analysis conditions are as follows. The sodium content was 0.2% by mass.

{ICP analysis conditions}
Device: optima 4300DV (made by Perkin Elemer)
Argon flow rate: 0.65 L / min Standard sample: Sodium chloride standard solution (Kanto Chemical Co., Ltd.)

(Fabrication of negative electrode plate)
0.2% by mass, 0.2% by mass of furnace black, 0.2% by mass of furnace black, 1.0% by mass of barium lignin sulfonate (example: phenol resin PR) or sodium lignin sulfonate (comparative example) Were added to lead powder (average particle diameter 2 μm) and then dry mixed (standard of blending amount: total mass of lead powder). Next, it knead | mixed, adding dilute sulfuric acid (specific gravity 1.26 (20 degreeC conversion)) and water, and the negative electrode paste was produced. The negative electrode paste was filled in a 1.0 mm thick expanded current collector (lead-calcium-tin alloy) to prepare a negative electrode plate. The negative electrode plate was left to stand for 20 hours in a normal atmosphere at a temperature of 50 ° C. and a humidity of 95% for aging, and then dried in an atmosphere at a temperature of 50 ° C. to obtain an unformed negative electrode plate.

(Production of positive plate)
0.1% by mass (standard: total mass of lead powder) reinforcing short fibers (polyethylene acrylic fibers) were added to lead powder (average particle diameter 2 μm) and then dry mixed. Next, diluted sulfuric acid (specific gravity 1.28 (converted to 20 ° C.)) and water were added and kneaded to prepare a positive electrode paste. The positive electrode current collector (lead-calcium-tin alloy) consisting of an expanded grid body is filled with the positive electrode paste, and left for aging for 20 hours in an atmosphere of temperature 50 ° C. and humidity 95% for aging. It dried under the atmosphere of ° C and obtained an unformed positive electrode plate.

(Assembly of battery)
The unformed negative electrode plate was inserted into the polyethylene separator processed into a bag shape. Next, six unformed negative electrode plates and five unformed positive electrode plates are formed so that the unformed positive electrode plate and the unformed negative electrode plate inserted in the bag-like separator are alternately laminated. Stacked. Subsequently, the ears of the electrode plates of the same polarity were welded together by a cast-on-strap (COS) method to produce an electrode group. The electrode group was inserted into the battery case to assemble a 2 V single cell battery. Diluted sulfuric acid (specific gravity 1.24 (20 ° C. conversion)) was poured into this battery, and then chemical conversion was carried out at a current of 10.0 A for 15 hours in a 40 ° C. water tank. Then, after the diluted sulfuric acid was discharged, diluted sulfuric acid with a specific gravity of 1.28 (20 ° C. conversion) was again injected to obtain a lead storage battery.

(Evaluation of battery characteristics)
The charge acceptance, discharge characteristics and cycle characteristics were measured by the same method as in Experiment A. The measurement results of the charge acceptance, the discharge characteristic and the cycle characteristic of Comparative Example B1 were each set to 100, and each characteristic was relatively evaluated. The results are shown in Table 2.

  In the example, it can be confirmed that the charge acceptance is improved as compared with the comparative example. Further, in the example, it can be confirmed that the excellent charge acceptance, the discharge characteristic and the cycle characteristic are compatible.

  ADVANTAGE OF THE INVENTION According to this invention, lead acid battery resin which has the outstanding charge acceptance in a lead acid battery can be provided. According to the present invention, it is possible to provide a resin for a lead storage battery which is excellent in charge acceptance, discharge characteristics and cycle characteristics. Moreover, according to this invention, the resin composition containing said resin for lead storage batteries can be provided. Furthermore, according to the present invention, it is possible to provide an electrode containing the resin for a lead storage battery. The present invention can provide a lead-acid battery comprising the electrode. The present invention can provide an automobile provided with the lead storage battery.

  DESCRIPTION OF SYMBOLS 1 ... lead storage battery, 2 ... battery case, 3 ... lid, 4 ... positive electrode terminal, 5 ... negative electrode terminal, 6 ... liquid port plug, 11 ... electrode plate group, 12 ... positive electrode plate, 13 ... negative electrode plate, 14 ... separator, 15 ... positive electrode side strap, 16 ... negative electrode side strap, 17 ... inter-cell connection part, 18 ... pole post, 22, 32 ... current collecting part.

Claims (7)

It is a resin having a structural unit derived from a phenolic compound,
Resin for lead storage battery containing potassium sulfonate base.   The resin for lead acid battery according to claim 1, wherein the structural unit contains a structural unit derived from a bisphenol-based compound.   The resin for lead acid battery according to claim 1, wherein the structural unit comprises a structural unit derived from lignin.   The resin for a lead acid battery according to claim 3, having a weight average molecular weight of 3000 to 50000.   The electrode containing the electrode active material and resin for lead acid batteries as described in any one of Claims 1-4.   A lead-acid battery comprising the electrode according to claim 5.   An automobile comprising the lead-acid battery according to claim 6.