JPS62122076A - Large sealed lead-acid battery - Google Patents

Abstract

PURPOSE:To increase high rate performance, to prevent drying-up of battery caused by decrease in electrolyte, and to lengthen the life, by immersing the lower part of a plate group having a hydrophilic porous separator whose liquid holding capacity is smaller than that of an active material. CONSTITUTION:The lower part of a plate group is immersed into an electrolyte 8. Since the whole, especially the lower part of a separator 3 is sufficiently wet, the electrical resistance of a battery is low. Since the upper part of a negative plate 2 is extruded from the electrolyte level, the closed reaction based on an oxygen cycle is advanced smoothly and decrease in electrolyte is small. Lateral frames 10, 10' of the grid of a positive plate 1 are arranged zigzag, and a positive active material 11 is placed continuously without separating by the lateral frames 10, 10'. The surface area of the positive active material is 2m<2>/g or more and that of a negative active material is 0.2m<2>/g or more. They are microporous body having small pore size and have large liquid holding capacity and suck electrolyte by capillarity.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to non-maintainable lead-acid batteries, particularly low-temperature rapid tI1. This paper relates to the improvement of large batteries where electrical characteristics are important.

Conventional technology and its problems Sealed lead-acid batteries that use an antimony-free alloy for the grid and react with oxygen gas generated from the positive electrode plate with the negative electrode plate, so-called oxygen cycle reaction, do not require rehydration and do not leak even if tipped over. It has the characteristic that it does not. Recently, this type of sealed battery has begun to be used not only as a power source for small portable devices, but also for fairly large batteries such as automobile batteries and stationary batteries.

Self! For large batteries such as eII batteries and stationary W1 batteries,
They are not carried around, and there is a small requirement for no leakage in case of a fall, but there are high requirements for rapid discharge performance and long life performance.

Conventional sealed lead-acid batteries often use a porous plate mainly made of glass fiber with an average diameter of 1 μm or less and an average pore size of 20 μm or more as a separator, and the electrolyte is completely impregnated into the electrode plate group. When a battery with this configuration is made large in size, the upper part becomes dry and has a high resistance, resulting in poor rapid discharge characteristics, and there is also a problem that the battery life is shortened due to dry-up due to the small number of wave crests.

If the upper part is sufficiently impregnated with electrolyte, the lower part will be in a puddle state, making it difficult for the sealing reaction due to the oxygen cycle to proceed, and there is a problem that explosive gas and rancid gas will be generated during charging, making it impossible to take advantage of the characteristics of a sealed battery. .

Means for Solving the Problems The present invention provides a structure in which the lower part of an electrode plate group having a hydrophilic porous separator having a smaller liquid holding capacity than the active material is immersed in an electrolytic solution, and the active material is continuous in the vertical direction. By using a plate of
This solves the conventional problems of large sealed batteries with a diameter of 0.00 mm or more.

Function In the lead-acid battery according to the present invention, the lower part of the electrode plate group is immersed in the electrolytic solution, and the entire separator, especially the lower part, is sufficiently wet, so that the electrical resistance is low. In addition, since the upper part of the negative electrode plate is exposed from the electrolytic solution surface, the sealing reaction by the M solution progresses sufficiently, and the T and M solutions are naturally reduced. The loss of water due to a small amount of gas generation is limited to a decrease in the fluid electrolyte and does not lead to deterioration due to drying of the electrode plate group. Furthermore, since the active material has a large liquid holding capacity and a continuous structure in the vertical direction,
Since the electrolyte is well absorbed, the charging/discharging reaction progresses sufficiently in the upper part of the electrode plate group, resulting in good discharge characteristics.

EXAMPLE A lead-acid battery according to the present invention will be explained with reference to FIG. 1 is a positive electrode plate using a lattice made of an antimony-free alloy such as lead-calcium-tin, 2 is a negative plate, and 3 is a porous separator made of a hydrophilic material, including glass fiber with an average diameter of 10 μl or less, and wood-loving polyethylene. A mat mainly composed of fibers or the like is preferable.

4 is a battery case, 5 is a lid that projects upward from the bottom of the battery case, 6 is a lid, 7 is an exhaust valve provided on the lid, 8 is an electrolytic solution, and 8' is the liquid level.

FIG. 2 is a longitudinal cross-sectional view of the positive electrode plate 2, in which 9 is a frame of a lattice, and 10 and 10' are horizontal bars of the lattice, which are arranged in a staggered manner at alternate positions. 11 is the positive electrode active material, horizontal bar 1
0 and 10' are continuous without being separated in the vertical direction. The surface area of 1 Tachibana active material is 2n! /1 or more, and the surface area of the negative electrode active material is 0.2nf /1 or more, that is, it is a microporous material with a small pore diameter, and has a large liquid retention capacity and absorbs the electrolyte by capillary action.

In FIG. 1, in order to prevent short-circuiting at the bottom due to falling of the positive electrode active material, a cracker is provided that has the effect of separating fallen matter from the electrode plate group. However, if the negative electrode plate, especially its lower part, is wrapped with a separator, short circuits will not occur, so a cracker will be unnecessary.

The structure in which the active material is continuous in the vertical direction is positive IfA.
This is an essential condition for the roots, but it is more preferable to use this structure for the negative electrode plate as well. To obtain an electrode plate with this structure, in addition to staggering the horizontal bars in a normal cast grid, applying a thick layer of paste and making it continuous on both sides of the grid bars will further improve the suction of the electric WE liquid. It is preferable.

Effects of the Invention The large sealed lead-acid battery of the present invention differs from conventional batteries in which all electrolyte is impregnated and held in the electrode plate group, but the lower part of the electrode plate group is immersed in the electrolyte, so it has excellent rapid discharge characteristics. Not only is there no dry-up caused by a decrease in electrolyte;
L lifespan.

[Brief explanation of drawings]

FIG. 1 is a cutaway vertical cross-sectional view showing a large sealed lead-acid battery according to the present invention, and FIG. 2 is a cross-sectional view showing an example of a positive electrode plate used in the battery. DESCRIPTION OF SYMBOLS 1... Positive electrode plate, 2... Negative electrode plate, 3... Separator, 5... Battery container cracker, 7... Exhaust valve, 8... Electrolyte, 8'... Electrolyte solution surface , 9... Lattice picture frame, 10.10
'... Grid horizontal bar, 11... Positive electrode active material

Claims (1)

[Claims] 1. Oxygen, characterized in that the lower part of the electrode plate group having a hydrophilic porous separator with a smaller liquid retention capacity than the active material is immersed in an electrolytic solution, and the electrode plate has a structure in which the active material is continuous in the vertical direction. Plate height 100mm due to cycle reaction
or larger sealed lead acid batteries.