JPS584264A - Plate for lead storage battery - Google Patents

Abstract

PURPOSE:To prevent any adherence between adjacent plates, which might be caused during the initial charge, by forming the plate so that its peripheral part doesn't become in contact with the peripheral part of another plate. CONSTITUTION:The upper figure indicates a part of a plate which adheres to the same part of another plate, while tha lower figure is a magnified sectional figure of the peripheral part of the plate. The plate is manufactured by packing a paste into a grid of 105mm. thickness so that the tickness (X) of its central part 2 becomes about 2mm.. Right after packing of the paste into the grid is completed, a peripheral part 1 is pressed with a roller so that the thickness (Y) of the part 1 becomes 1.5mm., thereby making a plate the peripheral part 1 of which is thinner than the central part 2. As a result, since lead metal, which is deposited over the surface of the plate due to a reducing reaction caused during the usual initial charge, doesn't grow into a thickness of over around 0.25mm., any adherence of the plate at the peripheral part 1 is prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention 1191i relates to an electrode plate constituting a lead-acid battery.

One of the methods for manufacturing lead-acid batteries is as follows.

In other words, a square grid made of lead alloy is filled with a paste-like active material mainly composed of lead oxide and lead sulfate, dried and aged, and then charged for the first time to form a cathode plate and an anode plate. This method is then assembled into a lead-acid battery.

Conventionally, in the first charge using this method, for example, 3 to 6
A four-piece stack of cathode plates! 0 to SO pieces are connected in parallel and an anode plate block is placed between them.
This is done by adding dilute sulfuric acid.

When initial charging is performed with a block such as No. 2 in which the cathode plates are in close contact with each other, there is a problem that the cathode plates stick to each other. This is because the reduction reaction from lead sulfate to metallic lead occurs when they are in close contact with each other, so even the active material of the adjacent electrode plate is reduced as if it were its own active material. This is a phenomenon in which it sticks.

By the way, when assembling a lead-acid battery, there is a dry wart assembly process! It is necessary to pass through the electrodes, and the electrode plates must be cut out one by one. However, as mentioned above, if it adheres during the first charging, it will be difficult to handle afterwards, resulting in an extremely low operating rate, an increase in man-hours to separate it, and an increase in product complaints due to unnecessary drying and poor assembly. .

This 1IW14 is a product that solves the phenomenon of adhesion on the cathode plate during initial charging by utilizing the characteristics that occur. The characteristic is that adhesion occurs on the periphery 1 of the pole plate, as indicated by diagonal lines in FIG.

This is considered to be because the cross-sectional area of the lattice in the peripheral part 1 is large, so that the current density at the time of initial charging is large h<, and even the active material of the adjacent electrode plate is reduced.

Therefore, in the present invention, the occurrence of adhesion is prevented by providing a structure in which the peripheral parts of adjacent electrode plates do not come into contact with each other during initial charging.

An embodiment of the present invention will be described.

In FIG. 2, which shows an enlarged cross-sectional view of the peripheral part of the electrode plate, this electrode plate has a grid with a thickness of L6TIIIg filled with paste,
The central portion 2 is manufactured to have a thickness X of approximately 2 m.

Immediately after filling, the peripheral part 1 was pressed with a roller and rolled to a thickness equal to the thickness of the peripheral part 1 to form an electrode plate in which the peripheral part 1 was thinner than the central part 2. Metallic lead, which usually precipitates on the surface of the electrode plate due to the reduction reaction that occurs during initial charging, does not grow in the thickness direction of the electrode plate to an extent that exceeds the A2S resistance. Therefore, in the above-described electrode plate, by preventing adhesion at the peripheral portion 1, it is possible to prevent the electrode plate from adhering.

Sokote, length 1sOIlI+, width 100m, thickness 20I
After initial charging by stacking four IllI cathode plates, adhesion strength was measured using randomly sampled blocks (samples @ n = 190). This measurement was performed by fixing one of two attached electrode plates and measuring the force in water when the other was pulled at a constant velocity (80 M/min).

Table 1 As shown in Table 1, the adhesion strength of the electrode plate of the present invention was lowered to 17e of the conventional product, which caused a complete hindrance in subsequent manufacturing, and also had a negative impact on the performance of the cathode plate. No effect was observed. The variation in adhesion strength shown in Table 1 is considered to be due to bending of the electrode plate during initial charging or non-uniformity of the processing roller.

Another way to change the thickness around the electrode plate is to reduce the thickness of the grid in that area and lower the gate that determines the filling thickness of the paste filling machine in that area. .

However, according to the present invention, problems in the electrode plate manufacturing process can be improved by simple operations, and the present invention has great industrial value since it does not adversely affect battery performance.

[Brief explanation of drawings]

1 is an explanatory diagram showing a portion where adhesion occurs between the electrode plates during initial charging, and FIG. 2 is an enlarged sectional view of the peripheral portion of the electrode plate showing an embodiment of the present invention. 1 is the peripheral part of the electrode plate, 2 is the central part of the electrode plate, X is the thickness of the central part of the electrode plate - Y is the thickness of the peripheral part of the electrode plate Patent applicant'

Claims (1)

[Claims] An electrode plate for a lead-acid battery, characterized in that the peripheral part of the electrode plate is thinner than the center part.