【発明の詳細な説明】[Detailed description of the invention]
本発明は、鉛蓄電池とくに無漏液、密閉形鉛蓄
電池の改良に関するものである。
従来この種の電池はPbあるいはPb−Ca系合金
の格子を用い、隔離体と電解液保持体の両方の機
能を兼備えたものとして径の細いガラス繊維をマ
ツト状にしたものを用いる。そして、該ガラス繊
維マツトに比重1.300〜1.350程度の硫酸を含浸
し、保持させただけの液量のきわめて少ない電池
である。したがつて、液漏れの心配がなく、また
充電中に陽極板から発生した酸素ガスは容易に陰
極板に移動し、陰極板に次に示す密閉反応によつ
て吸収されるという優れた特徴を有している。
１／2O2＋Pb→PbO
PbO＋H2SO4→PbSO4＋H2O
ところで、上記電池の隔離体と電解液保持体の
機能を兼備えたガラス繊維マツトは、気孔率が90
％以上あるが、内部短絡の防止と電池性能すなわ
ち電解液量をどれだけ確保するかということや放
電電圧の観点からその厚さを決めなければならな
い。ガラス繊維マツトと電池性能の間には、一般
に次の様な関係がある。
(1) マツトが厚い場合は電解液量が多く確保出来
るので低率放電での放電容量は大きく、かつ極
板間距離が広がるため内部短絡の危険性は減少
するが、電解液抵抗が増加し高率放電での電圧
特性が著しく低下する。
(2) マツトが薄い場合は上記と逆に低率放電での
放電容量は小さく、内部短絡の危険性が増大す
るが、高率放電での電圧特性は向上する。
上述したように、隔離体と電解液保持体の機能
を兼備えたガラス繊維マツトを用いる場合には一
長一短があり、全ての電池性能を満足するわけに
はいかない。従来は、とくに内部短絡を考慮して
該マツトの厚さは２mm程度のものを用いている
が、この場合には従来の自動車用電池のような液
タイプの電池に比べ高率放電特性が著しく劣ると
いう欠点がある。
本発明は上記の如き欠点を除去するもので、そ
の目的は、高率放電特性（とくに低温時）に優
れ、かつ内部短絡の危険性の少ない鉛蓄電池とく
に無漏液、密閉形鉛蓄電池を提供することにあ
る。
本発明の要点は、隔離体を兼ねた電解液保持体
と該保持体よりも薄い隔離体を陽極板と陰極板と
の間に交互に配置せしめた点にある。前記電解液
保持体としては、径の細いガラス繊維をマツト状
にしたものが望ましいが、耐酸性があり気孔率90
％以上で連通孔を有するようなものであれば、例
えば発泡樹脂でもかまわない。また、前記薄い隔
離体は、電解液保持体よりもきわめて薄い多孔質
合成樹脂フイルムが良い。第１図に本発明による
電池構成の概要を示す。ここで１は隔離体を兼ね
た電解液保持体、２は隔離体、３は陽極板、４は
陰極板である。電解液保持体１は、必要とされる
低率放電容量に応じた液量が確保出来るよう厚さ
を適宜設定出来る。低率放電時には、隔離体２を
介して対向する陽極板３、陰極板４の外側にある
電解液保持体１より電解液が供給される。隔離体
２はきわめて薄く電解液保持量がほとんどない
が、陰陽極板間距離を極端に短かく出来、この部
分での電気抵抗を下が得る。高率放電時には、こ
の部分への反応電流の集中が起こつても通常の２
倍が限度（通常は極板の両面に均等に電流が流
れ、本発明の電池での全ては電流が陰陽極板間距
離の短かい面に集中するとしても通常の２倍にし
かならないということ）であるため、隔離体２の
厚さを通常の1/2以下にすれば同等以上の電圧特
性が得られる。また、隔離体２は、通常70％程度
の気孔率を有するものであるため、この部分での
内部短絡を起こすことも少ない。
しかし、問題となるのは放電時陰陽極板への電
解液の供給が大部分電解液保持体１より行われ、
隔離体２にはほとんどその能力がないことであ
る。とくに低率放電時に、陰陽極板の隔離体２に
面している部分への電解液の移動がスムーズに行
われているかどうかという点にあるが、検討の結
果、極板厚さ1.5mm以下、活物質中の含水率12％
以上であれば、十分な電解液の移動が確保される
ことを見い出した。
したがつて上述したような電池構成によれば、
低率放電容量が確保出来、高率放電特性に優れ、
かつ内部短絡の少ない無漏液、密閉形鉛蓄電池が
得られる。
次に本発明の一実施例について説明する。
陽極板（W105mm×H120mm×t1.4mm）４枚、陰
極板（W105mm×H120mm×t1.2mm）４枚、隔離体
を兼ねた電解液保持体として径の細いガラス繊維
をマツト状にしたもの（W110mm×H127mm×t2
mm）５枚、隔離体として多孔質ポリエチレンフイ
ルム（W110mm×H127mm×t0.2mm）４枚を用い、
第１図に示す構成の開路電圧2Vの電池を製作し
た。
比較として、隔離体を兼ねた電解液保持体のみ
を使用した従来からの電池も製作した。極板は上
記実施例と同一のもので陽極板４枚、陰極板４
枚、電解液保持体も同一の材質で寸法がW110mm
×H127mm×t1.2mmのものである。
これらの電池は、極板群に20Kg／dm2の荷重が
かかるように電槽に収納し、電解液として比重
1.345（20℃）の希硫酸を210ml注入した後、排気
弁のついた蓋で密閉状態にした。
以上のようにして作製した２種類の電池につい
て、25℃、5.4A放電（低率放電）と０℃、150A
放電（高率放電）を行い、特性を比較した。その
結果は第１表と第２図に示した。低率放電容量
は、第１表に示したように両者ともほぼ同等であ
つた。高率放電特性は、第２図に示したように容
量は両者ともほぼ同等であつたが、電圧特性は本
発明密閉電池（曲線Ａ）がきわめて優れていた。
The present invention relates to improvements in lead-acid batteries, particularly leak-free, sealed lead-acid batteries. Conventionally, this type of battery uses a lattice made of Pb or Pb-Ca alloy, and uses a mat-shaped piece of glass fiber with a narrow diameter, which functions as both a separator and an electrolyte holder. This battery is made by simply impregnating the glass fiber mat with sulfuric acid having a specific gravity of about 1.300 to 1.350 and retaining it in a very small amount of liquid. Therefore, there is no need to worry about liquid leakage, and oxygen gas generated from the anode plate during charging easily moves to the cathode plate, where it is absorbed by the following sealing reaction. have. 1/2O 2 +Pb→PbO PbO+H 2 SO 4 →PbSO 4 +H 2 O By the way, the glass fiber mat that functions as the battery separator and electrolyte holder has a porosity of 90.
% or more, but its thickness must be determined from the viewpoints of preventing internal short circuits, battery performance, that is, how much electrolyte to secure, and discharge voltage. Generally, there is the following relationship between glass fiber mat and battery performance. (1) If the mat is thick, a large amount of electrolyte can be secured, so the discharge capacity at low rate discharge is large, and the distance between the electrodes is widened, reducing the risk of internal short circuits, but the electrolyte resistance increases. Voltage characteristics at high rate discharge deteriorate significantly. (2) If the mat is thin, contrary to the above, the discharge capacity during low rate discharge will be small and the risk of internal short circuit will increase, but the voltage characteristics will improve during high rate discharge. As mentioned above, there are advantages and disadvantages when using a glass fiber mat that has both the functions of a separator and an electrolyte holder, and it is not possible to satisfy all battery performances. Conventionally, the thickness of the mat is about 2 mm, especially in consideration of internal short circuits, but in this case, the high rate discharge characteristics are significantly higher than that of liquid type batteries such as conventional automobile batteries. It has the disadvantage of being inferior. The present invention aims to eliminate the above-mentioned drawbacks, and its purpose is to provide a lead-acid battery, particularly a leak-free, sealed lead-acid battery, which has excellent high-rate discharge characteristics (especially at low temperatures) and has a low risk of internal short circuits. It's about doing. The gist of the present invention is that electrolyte holders that also serve as separators and separators thinner than the holders are alternately arranged between the anode plate and the cathode plate. As the electrolyte holder, it is preferable to use a mat-shaped glass fiber with a small diameter, which is acid-resistant and has a porosity of 90.
For example, a foamed resin may be used as long as it has communicating holes at % or more. Further, the thin separator is preferably a porous synthetic resin film that is much thinner than the electrolyte holder. FIG. 1 shows an outline of the battery configuration according to the present invention. Here, 1 is an electrolytic solution holder that also serves as a separator, 2 is a separator, 3 is an anode plate, and 4 is a cathode plate. The thickness of the electrolytic solution holder 1 can be set as appropriate so that the amount of solution corresponding to the required low rate discharge capacity can be secured. During low rate discharge, an electrolytic solution is supplied from an electrolytic solution holder 1 located outside an anode plate 3 and a cathode plate 4 that face each other with a separator 2 in between. Although the separator 2 is extremely thin and holds almost no amount of electrolyte, the distance between the negative and anode plates can be made extremely short, and the electrical resistance in this area can be lowered. During high rate discharge, even if the reaction current is concentrated in this area, the normal 2
(Normally, current flows evenly on both sides of the electrode plates, but in the case of the battery of the present invention, even if the current is concentrated on the side where the distance between the negative and anode plates is short, it will only be twice the normal amount.) ) Therefore, if the thickness of the separator 2 is reduced to 1/2 or less of the normal thickness, voltage characteristics equal to or higher than the normal thickness can be obtained. Furthermore, since the separator 2 usually has a porosity of about 70%, internal short circuits are less likely to occur in this portion. However, the problem is that most of the electrolyte is supplied to the cathode and anode plates during discharge from the electrolyte holder 1;
Isolator 2 has almost no such ability. In particular, the issue is whether the electrolyte moves smoothly to the part of the cathode and anode plates facing the separator 2 during low rate discharge, and as a result of consideration, we found that the electrode plate thickness should be 1.5 mm or less. , water content in active material 12%
It has been found that with the above conditions, sufficient movement of the electrolytic solution is ensured. Therefore, according to the battery configuration as described above,
It can secure low rate discharge capacity and has excellent high rate discharge characteristics.
In addition, a leak-free, sealed lead-acid battery with few internal short circuits can be obtained. Next, one embodiment of the present invention will be described. 4 anode plates (W105mm x H120mm x T1.4mm), 4 cathode plates (W105mm x H120mm x T1.2mm), and a pine-shaped glass fiber with a narrow diameter as an electrolyte holder that also serves as a separator ( W110mm×H127mm×t2
mm) and 4 porous polyethylene films (W110mm x H127mm x T0.2mm) as separators.
A battery with an open circuit voltage of 2 V and the configuration shown in Fig. 1 was manufactured. For comparison, we also fabricated a conventional battery using only an electrolyte holder that also served as a separator. The electrode plates are the same as those in the above embodiment, including 4 anode plates and 4 cathode plates.
The electrolyte holder is also made of the same material and the dimensions are W110mm.
×H127mm×T1.2mm. These batteries are stored in a container so that a load of 20 kg/ dm2 is applied to the electrode plate group, and the specific gravity is
After injecting 210 ml of dilute sulfuric acid at 1.345 (20°C), it was sealed with a lid equipped with an exhaust valve. Regarding the two types of batteries produced as described above, 25℃, 5.4A discharge (low rate discharge) and 0℃, 150A
A discharge (high rate discharge) was performed and the characteristics were compared. The results are shown in Table 1 and Figure 2. As shown in Table 1, the low rate discharge capacity was almost the same in both cases. Regarding the high rate discharge characteristics, as shown in FIG. 2, the capacity was almost the same for both batteries, but the voltage characteristics of the sealed battery of the present invention (curve A) were extremely superior.
【表】
これらのことは、本発明の電池の構成によれば
他の性能を維持しつつ、従来欠点とされていた出
力特性を大幅に改善出来ることを意味し、その用
途の拡大がはかられる。特にこれまで不向きとれ
ていた自動車用電池のような軽量でしかも高出力
を要求されているものについて使用することが可
能である。このように本発明は工業的価値の高い
ものである。[Table] These things mean that according to the battery configuration of the present invention, the output characteristics, which were conventionally considered to be a drawback, can be significantly improved while maintaining other performances, and its applications are expected to expand. It will be done. In particular, it can be used for batteries that are lightweight and require high output, such as automobile batteries, which have not been suitable until now. As described above, the present invention has high industrial value.
【図面の簡単な説明】[Brief explanation of the drawing]
第１図は本発明の電池構成の概要図、第２図は
本発明と従来電池の高率放電（０℃、150A放電）
時の電池電圧と容量の関係を示す曲線図である。
１は隔離体を兼ねた電解液保持体、２は隔離
体、３は陽極板、４は陰極板。
Figure 1 is a schematic diagram of the battery configuration of the present invention, and Figure 2 is a high rate discharge (0°C, 150A discharge) of the present invention and conventional battery.
FIG. 3 is a curve diagram showing the relationship between battery voltage and capacity at different times. 1 is an electrolyte holder that also serves as a separator, 2 is a separator, 3 is an anode plate, and 4 is a cathode plate.