JP2004014283A

JP2004014283A - Valve regulated lead battery

Info

Publication number: JP2004014283A
Application number: JP2002165799A
Authority: JP
Inventors: Shoji Horie; 堀江　章二; Yoshibumi Hisama; 久間　義文
Original assignee: Matsushita Electric Industrial Co Ltd
Current assignee: Panasonic Holdings Corp
Priority date: 2002-06-06
Filing date: 2002-06-06
Publication date: 2004-01-15
Anticipated expiration: 2022-06-06
Also published as: JP4507483B2

Abstract

<P>PROBLEM TO BE SOLVED: To provide a valve-regulated lead battery excellent in discharge properties and oxygen-absorbing capability, having a structure in which a pole plate group is partially soaked in electrolyte solution, and to prevent a dendrite short circuit due to over-discharge continuation. <P>SOLUTION: In the valve regulated lead battery, the pole plate 6, which comprises positive plates 2, negative plates 3 and separators 5, is partially soaked in a electrolyte solution 4 and partially exposed in the air and a space 10 is formed between a battery case 7 and the plates group 6. Provided that the weights of positive and negative active materials are P and N, respectively, and the amount of sulfuric acid in the electrolyte solution is E, the ratio of the amount of sulfuric acid to the sum of the weights of positive and negative active materials (E/(P/N)) is adjusted within the range of 0.25 to 0.35. <P>COPYRIGHT: (C)2004,JPO

Description

【０００１】
【発明の属する技術分野】
本発明は制御弁式鉛蓄電池に関するものである。
【０００２】
【従来の技術】
制御弁式鉛蓄電池は、充電時の酸素ならびに水素ガスの発生が極めて少なく、補水の必要がない等の利点を有し、様々な用途に広く用いられている。
【０００３】
しかしながら、充電時のガス発生を抑制するために、負極で酸素ガスを吸収する機構とするために、電解液のほとんどを正極、負極ならびにセパレータに含浸させる構成としていて、流動できる電解液が豊富な液式の鉛蓄電池に比べて、活物質量に対する電解液中の硫酸量が少ない構成となっている。このため、制御弁式鉛蓄電池は、電解液が豊富な液式の鉛蓄電池に比べて放電容量が小さい。このような課題を解決するため、極板群下部のみを流動可能な電解液に浸漬した構成が提案されている。
【０００４】
しかしながら、極板群下部のみを電解液に浸漬した構成であっても、液式の鉛蓄電池と比較すると、活物質量に対する硫酸量は少ないため、電池容量を超えて過放電されると、活物質よりも硫酸が先に消費され、電解液が中性の水になって、デンドライトショートが発生するという課題がある。特に、活物質量に対する硫酸量が同じであっても、極板群下部のみを電解液に浸漬した構成の場合、流動できる電解液が存在しない構成に比べて、早期にデンドライトショートが発生することが明らかになってきた。
【０００５】
【発明が解決しようとする課題】
前記する従来技術の問題点に鑑み、本発明が解決しようとする課題は、過放電放置によるデンドライトショートを抑制するとともに、放電特性と酸素ガス吸収能力に優れた制御弁式鉛蓄電池を提供することにある。
【０００６】
【課題を解決するための手段】
このような課題を解決するために、本発明の請求項１記載に係る発明は、正極板、負極板およびセパレータからなる極板群の一部が電解液に浸漬されるとともに、前記極板群の他の部分が電解液から露出し、前記極板群の極板積層面と電槽壁との間に空間部を形成した制御弁式鉛蓄電池であって、正極活物質量をＰとし、負極活物質量をＮとし、前記電解液中に含まれる硫酸量をＥとした場合において、正極活物質ならびに負極活物質を合わせた質量に対する硫酸量の比率、すなわち、Ｅ／（Ｐ＋Ｎ）を、０．２５〜０．３５とするものである。
【０００７】
本発明の請求項２記載に係る発明は、請求項１記載の構成を備えた制御弁式鉛蓄電池において、正極活物質量に対する負極活物質量の比率Ｎ／Ｐを０．８〜１．０とするものである。
【０００８】
【発明の実施の形態】
本発明の目的は、各請求項に記載した構成を実施の形態とすることにより達成できるのであるが、以下には本発明の一実施の形態を図を参照して説明し、一実施の形態の構成による作用を併記して、上記構成の意義を明らかにする。
【０００９】
図１ならびに図２に示したように、本発明の制御弁式鉛蓄電池１は正極板２と負極板３との間に電解液４を含浸するセパレータ５を介在させた極板群６が電槽７に収納された構成を備えている。この電槽７の極板面に対向する内壁８にリブ９を形成して、極板群６の極板積層面と内壁８との間に空間部１０を設けて、流動できる電解液４を有している。
【００１０】
本発明では極板群を構成する正極板２に充填された正極活物質量をＰ、極板群を構成する負極板３に充填された負極活物質量をＮ、電解液４中に含まれる硫酸の質量をＥとした場合に、比率｛Ｅ／（Ｐ＋Ｎ）｝を、０．２５〜０．３５とする。
【００１１】
極板群下部のみを電解液に浸漬した構成の場合、電解液に浸漬されていない極板群上部では、下部よりも先に硫酸が消費されて、デンドライトが生成し易い状況にあるが、比率｛Ｅ／（Ｐ＋Ｎ）｝を０．２５以上とすることによって、硫酸が消費されて電解液が中性の水になる前に、実際に放電可能な活物質がほとんど消費されているために、放電反応の進行すなわち硫酸の消費を遅らせることができる。よって、電解液の中性化に伴う鉛の溶解を抑制し、充電時のデンドライトの生成を抑制できるものである。
【００１２】
また、好ましくは正極活物質量Ｐに対する負極活物質量Ｎの比率（Ｎ／Ｐ）を０．８〜１．０の範囲とすることによって放電容量を確保しつつ、負極での酸素ガス吸収反応に基く密閉反応効率の低下を抑制することができる。
【００１３】
【実施例】
前記の本発明の一実施の形態による制御弁式鉛蓄電池と従来例の制御弁式鉛蓄電池を作製して試験評価を実施した。
【００１４】
すなわち、Ｐｂ−Ｃａ−Ｓｎ合金の圧延体をエキスパンド加工した格子体を備えた正極板ならびに負極板とセパレータから極板群を構成し、これを内壁にリブを設けた電槽に収納して極板群と電槽内壁との間に空間部を設け、流動可能な電解液の液面高さを極板高さの１／３程度とした構成と、電解液のほとんどすべてを正負極板とセパレータに含浸させ、流動できる電解液が存在しない構成で、５５Ｄ２３形の自動車用の制御弁式鉛蓄電池（以降、電池という）を表１に示すように種々作製した。
【００１５】
【表１】

【００１６】
これらの電池について、過放電放置試験を実施し、負極板表面で発生した樹枝状電析物であるデンドライトによる正極−負極間の短絡（以下、デンドライトショートという）の有無を調査した。具体的には、５時間率放電の後に、放電電流３０ｍＡ相当の抵抗を電池に接続した状態で放置して過放電させ、ある期間経過した後に１４Ｖで４時間充電し、電池を解体してデンドライトショートの有無を確認した。その試験結果を図３に示す。なお、比率｛Ｅ／（Ｐ＋Ｎ）｝は、正極活物質ならびに負極活物質を合わせた質量に対する硫酸量の比率を示している。また、新品時の５時間率容量を図４に示す。
【００１７】
図３から明らかなように、活物質量に対する硫酸量の比率｛Ｅ／（Ｐ＋Ｎ）｝が同じであっても、極板群下部のみを電解液に浸漬した構成の流動電解液が存在する場合、流動できる電解液が存在しない構成に比べて、早期にデンドライトショートが発生している。しかしながら、比率｛Ｅ／（Ｐ＋Ｎ）｝が０．２５以上では、流動電解液の有無によるデンドライトショート発生の違いがわずかとなっており、流動電解液が存在する構成における固有の課題が抑制されているものである。
【００１８】
過放電や自己放電に伴って、正負極活物質ならびに硫酸は消費されていくが、極板群下部のみを電解液に浸漬した構成の場合、電解液に浸漬されていない極板群上部では、下部よりも先に硫酸が消費されて、デンドライトが生成し易い状況にあるが、比率｛Ｅ／（Ｐ＋Ｎ）｝を、０．２５以上とした構成では、硫酸が消費されて電解液が中性の水になる前に、実際に放電可能な活物質がほとんど消費されているために、放電反応の進行、すなわち硫酸の消費を遅らせることができる。よって、電解液の中性化に伴う鉛の溶解を抑制し、充電時のデンドライトの生成を抑制できるものである。
【００１９】
一方、極板群下部のみを電解液に浸漬した構成の場合、電池の５時間率容量については、図４に示すように、正極活物質ならびに負極活物質を合わせた質量に対する硫酸量の比率｛Ｅ／（Ｐ＋Ｎ）｝が０．３５を超えると、放電容量が活物質量に制限されてしまい、比率｛Ｅ／（Ｐ＋Ｎ）｝が０．１５では、電槽内容積に制限があるために活物質量が多くなって硫酸量が確保できないために、放電容量が低下した。
【００２０】
以上より、本発明例のように、正極活物質ならびに負極活物質を合わせた質量に対する硫酸量の比率｛Ｅ／（Ｐ＋Ｎ）｝を０．２５〜０．３５とした構成にすることで、デンドライトショートの発生を大幅に抑制しつつ、放電容量を確保できる。
【００２１】
次に、極板群下部のみを電解液に浸漬した構成で、比率｛Ｅ／（Ｐ＋Ｎ）｝を０．３０とし、正極活物質量に対する負極活物質量の比率（Ｎ／Ｐ）を０．７〜１．１の範囲で、前記と同様に制御弁式鉛蓄電池を作製し、５時間率容量ならびに負極での酸素ガス吸収能力を評価するために密閉反応効率を調査した。その結果を図５ならびに図６に示す。
【００２２】
５時間率容量は比率（Ｎ／Ｐ）が１．０を超えると放電容量が正極活物質量に制限されて放電容量が低下し、比率（Ｎ／Ｐ）が０．８未満では負極での酸素ガス吸収能力が不充分となり、密閉反応効率は大きく低下した。これらの点から、正極活物質量に対する負極活物質量の比率（Ｎ／Ｐ）は０．８〜１．０の範囲が有効であることが明らかである。
【００２３】
ところで、上記実施例の電池は、いずれも、極板群と電槽内壁との間に空間部を設けた構成とし、流動できる電解液を確保できるものであるが、このような空間部がほとんどなく、流動できる電解液が極めて少ない構成の従来の制御弁式鉛蓄電池において、比率｛Ｅ／（Ｐ＋Ｎ）｝を０．２５〜０．３５にする場合では、セパレータを厚く、あるいは活物質の密度を小さくして、硫酸量を確保するための空間をさらに増やす構成となる。しかしながら、セパレータを厚くすると極板間が広くなって高率放電特性を低下させてしまい、活物質密度を小さくすることは活物質粒子間の結合力を低下させて、サイクル寿命の低下を招いてしまう。また、電解液の硫酸濃度を高くすることによって硫酸量を確保することも考えられるが、高濃度の硫酸を用いることは、正極格子腐食の進行や充電受入性の低下を招くことになるので、硫酸濃度を高くすることのみによって硫酸量の比率を高めることは好ましくない。
【００２４】
【発明の効果】
以上説明したように、本発明によれば、極板群と電槽壁との間に空間部が形成されていて、極板群の一部が電解液に浸漬された構成の制御弁式鉛蓄電池において、発生するデンドライトショートを抑制するとともに、放電特性と酸素ガス吸収能力に優れた制御弁式鉛蓄電池を得ることが可能となる。
【図面の簡単な説明】
【図１】本発明の一実施の形態における極板群、電槽ならびに電解液の構成を示す垂直方向の断面図
【図２】同水平方向の断面図
【図３】比率｛Ｅ／（Ｐ＋Ｎ）｝とデンドライトショート発生までの期間の関係を示す図
【図４】比率｛Ｅ／（Ｐ＋Ｎ）｝と５時間率容量の関係を示す図
【図５】比率（Ｐ／Ｎ）と５時間率容量の関係を示す図
【図６】比率（Ｐ／Ｎ）と密閉反応効率の関係を示す図
【符号の説明】
１　制御弁式鉛蓄電池
２　正極板
３　負極板
４　電解液
５　セパレータ
６　極板群
７　電槽
８　内壁
９　リブ
１０　空間部[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a control valve type lead storage battery.
[0002]
[Prior art]
The control valve type lead storage battery has advantages such as extremely low generation of oxygen and hydrogen gas at the time of charging and no need for water replenishment, and is widely used for various applications.
[0003]
However, in order to suppress gas generation during charging, in order to have a mechanism for absorbing oxygen gas at the negative electrode, most of the electrolytic solution is impregnated into the positive electrode, the negative electrode and the separator, and the flowable electrolytic solution is abundant. The configuration is such that the amount of sulfuric acid in the electrolytic solution relative to the amount of active material is smaller than that of a liquid-type lead storage battery. For this reason, the discharge capacity of the control valve type lead storage battery is smaller than that of the liquid lead storage battery rich in electrolyte. In order to solve such a problem, a configuration in which only the lower part of the electrode plate group is immersed in a flowable electrolyte has been proposed.
[0004]
However, even in a configuration in which only the lower part of the electrode plate group is immersed in the electrolyte, the amount of sulfuric acid with respect to the amount of the active material is smaller than that of the liquid type lead-acid battery. There is a problem that the sulfuric acid is consumed before the substance, the electrolyte becomes neutral water, and a dendrite short circuit occurs. In particular, even when the amount of sulfuric acid with respect to the amount of active material is the same, in the configuration in which only the lower part of the electrode plate group is immersed in the electrolyte, dendrite short-circuit occurs earlier than in the configuration in which there is no flowable electrolyte. Has become apparent.
[0005]
[Problems to be solved by the invention]
In view of the above-mentioned problems of the prior art, the problem to be solved by the present invention is to provide a control valve type lead-acid battery that suppresses dendrite short-circuit due to over-discharge leaving and has excellent discharge characteristics and oxygen gas absorption capacity. It is in.
[0006]
[Means for Solving the Problems]
In order to solve such a problem, the invention according to claim 1 of the present invention is directed to an electrode plate group including a positive electrode plate, a negative electrode plate, and a part of an electrode plate group including a separator, which is immersed in an electrolytic solution. The other portion is exposed from the electrolytic solution, a control valve type lead-acid battery in which a space is formed between the electrode plate stacking surface of the electrode group and the battery case wall, and the positive electrode active material amount is P, When the amount of the negative electrode active material is N and the amount of sulfuric acid contained in the electrolytic solution is E, the ratio of the amount of sulfuric acid to the combined mass of the positive electrode active material and the negative electrode active material, that is, E / (P + N), 0.25 to 0.35.
[0007]
According to a second aspect of the present invention, in the control valve type lead-acid battery having the configuration of the first aspect, the ratio N / P of the amount of the negative electrode active material to the amount of the positive electrode active material is 0.8 to 1.0. It is assumed that.
[0008]
BEST MODE FOR CARRYING OUT THE INVENTION
The object of the present invention can be achieved by adopting the configuration described in each claim as an embodiment. Hereinafter, an embodiment of the present invention will be described with reference to the drawings. The significance of the above configuration will be clarified together with the operation of the configuration.
[0009]
As shown in FIGS. 1 and 2, in the control valve type lead-acid battery 1 of the present invention, an electrode plate group 6 in which a separator 5 impregnated with an electrolyte 4 is interposed between a positive electrode plate 2 and a negative electrode plate 3. It has a configuration housed in the tank 7. A rib 9 is formed on an inner wall 8 facing the electrode plate surface of the battery case 7, and a space 10 is provided between the electrode plate stacking surface of the electrode plate group 6 and the inner wall 8 so that the flowable electrolytic solution 4 is formed. Have.
[0010]
In the present invention, the amount of the positive electrode active material filled in the positive electrode plate 2 constituting the electrode plate group is P, the amount of the negative electrode active material filled in the negative electrode plate 3 constituting the electrode plate group is N, and the electrolyte solution 4 contains the same. Assuming that the mass of sulfuric acid is E, the ratio {E / (P + N)} is set to 0.25 to 0.35.
[0011]
In the configuration in which only the lower part of the electrode group is immersed in the electrolytic solution, sulfuric acid is consumed earlier than the lower part in the upper part of the electrode group not immersed in the electrolytic solution, and dendrites are easily generated. By setting {E / (P + N)} to be 0.25 or more, most of the active material that can actually be discharged is consumed before sulfuric acid is consumed and the electrolyte becomes neutral water. The progress of the discharge reaction, that is, the consumption of sulfuric acid, can be delayed. Therefore, the dissolution of lead accompanying the neutralization of the electrolytic solution can be suppressed, and the generation of dendrites during charging can be suppressed.
[0012]
Also, preferably, the ratio of the amount N of the negative electrode active material to the amount P of the positive electrode active material (N / P) is in the range of 0.8 to 1.0, so that the discharge capacity is secured and the oxygen gas absorption reaction at the negative electrode Of the closed reaction efficiency based on the
[0013]
【Example】
A control valve type lead-acid battery according to one embodiment of the present invention and a control valve type lead-acid battery of a conventional example were manufactured and tested and evaluated.
[0014]
That is, a positive electrode plate and a negative electrode plate provided with a grid body obtained by expanding a rolled body of a Pb—Ca—Sn alloy, a negative electrode plate, and a separator are formed into an electrode plate group. A space is provided between the plate group and the inner wall of the battery case, and the liquid level of the flowable electrolyte is set to about 1/3 of the height of the electrode plate. Various types of 55D23 type control valve type lead-acid batteries (hereinafter referred to as batteries) for automobiles were manufactured as shown in Table 1 in a configuration in which the separator was impregnated with no flowable electrolyte.
[0015]
[Table 1]

[0016]
These batteries were subjected to an overdischarge standing test to investigate whether or not there was a short circuit between the positive electrode and the negative electrode (hereinafter, referred to as a dendrite short) due to dendrites, which are dendrites generated on the surface of the negative electrode plate. Specifically, after a 5-hour rate discharge, the battery was left over-discharged with a resistance equivalent to a discharge current of 30 mA connected to the battery. After a certain period of time, the battery was charged at 14 V for 4 hours. We checked for shorts. FIG. 3 shows the test results. The ratio {E / (P + N)} indicates the ratio of the amount of sulfuric acid to the combined mass of the positive electrode active material and the negative electrode active material. FIG. 4 shows the 5-hour rate capacity at the time of new product.
[0017]
As is apparent from FIG. 3, even when the ratio {E / (P + N)} of the amount of sulfuric acid to the amount of the active material is the same, when a flowing electrolyte having a configuration in which only the lower part of the electrode plate group is immersed in the electrolyte is present. The dendrite short-circuit occurs earlier than in a configuration in which no flowable electrolyte solution exists. However, when the ratio {E / (P + N)} is 0.25 or more, the difference in the occurrence of dendrite short-circuit due to the presence or absence of the flowing electrolyte is small, and the inherent problem in the configuration in which the flowing electrolyte is present is suppressed. Is what it is.
[0018]
With the overdischarge and self-discharge, the positive and negative electrode active materials and sulfuric acid are consumed, but in the case of a configuration in which only the lower electrode group is immersed in the electrolyte, in the upper electrode group not immersed in the electrolyte, Sulfuric acid is consumed before the lower part, and dendrites are easily generated. However, in a configuration in which the ratio {E / (P + N)} is 0.25 or more, sulfuric acid is consumed and the electrolyte becomes neutral. Since most of the dischargeable active material is actually consumed before the water becomes water, the progress of the discharge reaction, that is, the consumption of sulfuric acid can be delayed. Therefore, the dissolution of lead accompanying the neutralization of the electrolytic solution can be suppressed, and the generation of dendrites during charging can be suppressed.
[0019]
On the other hand, in the case of a configuration in which only the lower part of the electrode plate group is immersed in the electrolytic solution, the 5-hour rate capacity of the battery is, as shown in FIG. 4, the ratio of the amount of sulfuric acid to the mass of the positive electrode active material and the negative electrode active material combined. When E / (P + N)} exceeds 0.35, the discharge capacity is limited to the amount of the active material, and when the ratio {E / (P + N)} is 0.15, the capacity in the battery case is limited. Since the amount of active material increased and the amount of sulfuric acid could not be secured, the discharge capacity decreased.
[0020]
As described above, as in the example of the present invention, the configuration in which the ratio {E / (P + N)} of the amount of sulfuric acid to the combined mass of the positive electrode active material and the negative electrode active material is set to 0.25 to 0.35, enables dendrite. Discharge capacity can be secured while significantly suppressing occurrence of short circuit.
[0021]
Next, only the lower part of the electrode plate group was immersed in the electrolytic solution, the ratio {E / (P + N)} was set to 0.30, and the ratio of the amount of the negative electrode active material to the amount of the positive electrode active material (N / P) was set to 0.1. In the range of 7 to 1.1, a control valve type lead-acid battery was prepared in the same manner as described above, and the sealed reaction efficiency was examined in order to evaluate the 5-hour rate capacity and the oxygen gas absorption capacity of the negative electrode. The results are shown in FIGS.
[0022]
When the ratio (N / P) exceeds 1.0, the discharge capacity is limited by the amount of the positive electrode active material, and the discharge capacity decreases. When the ratio (N / P) is less than 0.8, the capacity at the negative electrode decreases. The oxygen gas absorption capacity became insufficient, and the sealing reaction efficiency was greatly reduced. From these points, it is clear that the ratio (N / P) of the amount of the negative electrode active material to the amount of the positive electrode active material is effective in the range of 0.8 to 1.0.
[0023]
By the way, each of the batteries of the above embodiments has a configuration in which a space is provided between the electrode group and the inner wall of the battery case, and can secure a flowable electrolytic solution. When the ratio {E / (P + N)} is set to 0.25 to 0.35 in the conventional control valve type lead-acid battery having a configuration in which the flowable electrolyte is extremely small, the thickness of the separator or the density of the active material is increased. And the space for securing the amount of sulfuric acid is further increased. However, when the separator is thickened, the gap between the electrode plates is widened and the high-rate discharge characteristics are reduced, and reducing the active material density decreases the binding force between the active material particles, resulting in a decrease in cycle life. I will. It is also conceivable to secure the amount of sulfuric acid by increasing the concentration of sulfuric acid in the electrolytic solution.However, the use of a high concentration of sulfuric acid leads to the progress of positive electrode grid corrosion and a decrease in charge acceptability. It is not preferable to increase the ratio of the amount of sulfuric acid only by increasing the concentration of sulfuric acid.
[0024]
【The invention's effect】
As described above, according to the present invention, a control valve-type lead having a configuration in which a space is formed between an electrode group and a battery case wall, and a part of the electrode group is immersed in an electrolytic solution. In the storage battery, it is possible to obtain a control valve type lead storage battery which suppresses the occurrence of dendrite short-circuiting and has excellent discharge characteristics and oxygen gas absorption capacity.
[Brief description of the drawings]
FIG. 1 is a vertical cross-sectional view showing a configuration of an electrode group, a battery case, and an electrolytic solution according to an embodiment of the present invention. FIG. 2 is a horizontal cross-sectional view. FIG. 3 is a ratio ΔE / (P + N). FIG. 4 shows the relationship between the period up to the occurrence of a dendrite short. FIG. 4 shows the relationship between the ratio {E / (P + N)} and the 5-hour rate capacity. FIG. 5 shows the ratio (P / N) and the 5-hour rate. FIG. 6 shows the relationship between the capacities. FIG. 6 shows the relationship between the ratio (P / N) and the closed reaction efficiency.
DESCRIPTION OF SYMBOLS 1 Control valve type lead storage battery 2 Positive electrode plate 3 Negative electrode plate 4 Electrolyte 5 Separator 6 Electrode plate group 7 Battery case 8 Inner wall 9 Rib 10 Space part

Claims

正極板、負極板およびセパレータからなる極板群の一部が電解液に浸漬されるとともに、前記極板群の他の部分が電解液から露出し、前記極板群の極板積層面と電槽壁との間に空間部を形成した制御弁式鉛蓄電池であって、正極活物質量をＰとし、負極活物質量をＮとし、前記電解液中に含まれる硫酸量をＥとした場合において、前記正極活物質および前記負極活物質を合わせた質量であるＰ＋Ｎに対する硫酸量の比率であるＥ／（Ｐ＋Ｎ）を、０．２５〜０．３５としたことを特徴とする制御弁式鉛蓄電池。A part of the electrode plate group including the positive electrode plate, the negative electrode plate, and the separator is immersed in the electrolytic solution, and the other part of the electrode plate group is exposed from the electrolytic solution. A control valve type lead-acid battery in which a space is formed between a tank wall and a positive electrode active material amount P, a negative electrode active material amount N, and an amount of sulfuric acid contained in the electrolytic solution is E Wherein the ratio of sulfuric acid amount to P + N, which is the combined mass of the positive electrode active material and the negative electrode active material, E / (P + N) is set to 0.25 to 0.35. Storage battery.

前記正極活物質量Ｐに対する負極活物質量Ｎの比率であるＮ／Ｐを０．８〜１．０としたことを特徴とする請求項１に記載の制御弁式鉛蓄電池。The control valve type lead-acid battery according to claim 1, wherein N / P, which is a ratio of the amount N of the negative electrode active material to the amount P of the positive electrode active material, is set to 0.8 to 1.0.