JPS6112346B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement of a grid used in lead-acid batteries, and it is possible to make a very lightweight grid with high productivity without reducing voltage characteristics compared to conventional grids. The purpose is to provide a method that can be manufactured well.

Recently, there has been a strong demand for lighter weight lead-acid batteries for automobiles in order to improve fuel efficiency, and engine starting performance must be maintained as before.

In other words, it is necessary to reduce the weight without reducing the voltage characteristics. In response to this situation, several weight reduction proposals have been made for cast gratings, such as placing more lead around the current collecting ears and reducing the amount of lead in other parts. There was a limit to weight reduction due to the problem of lattice deformation during the process. Various lead alloy-synthetic resin composite lattices have also been considered, but all of them have the drawbacks of complicated manufacturing processes, poor productivity, and poor productivity although weight reduction can be achieved. .

The present invention provides a lattice body that is excellent in weight reduction and productivity.Hereinafter, a method for manufacturing the lattice body of the present invention will be explained based on examples. In this example, a grid structure made of synthetic resin is immersed in molten lead three times in total to form a grid structure.

A polypropylene lattice structure 1 having a shape similar to the conventional cast lattice shown in FIG. Pickle. The molten lead here is
The temperature was controlled at 335°C, and the immersion time was 0.3 seconds. After immersion, the material is cooled with cold air or cold water, and then immersed for the second time. The second time, as shown in Figure 2B, the current collecting ears are immersed downward, covering only 1/2 of the entire area. After immersion, cooling is performed in the same manner, and then immersion is performed for the third time. For the third time, as shown in Figure 2C, the current collecting ears are immersed downward to only 1/6 of the total area. If the molten lead is immersed for the second and third time at a constant temperature and immersion time, the thickness of the lead thin film formed will be different when it is formed on the surface of the synthetic resin and when it is formed on the surface of the formed lead thin film. The thickness increases significantly due to the difference in ease of formation. There are methods of increasing the temperature of the water or decreasing the immersion time to make the formed thin film thinner, but in this example, the latter method was used, and the thin film thickness was adjusted by sequentially shortening the immersion or pouring time. I went.

In this method of dipping or pouring the grid structure into molten lead or lead alloy two or more times, by sequentially shortening the immersion or pouring time from the second time onwards, these lattice structures can be coated on the coated lead or lead alloy. The lead or lead alloy film around the current collecting ear can be thickly coated without melting and losing it, and the thickness of the lead or lead alloy film around the current collecting ear can be increased more easily and accurately than in other parts.

The lead-synthetic resin composite lattice body produced in this manner is shown in FIG. In the figure, the part 3 was immersed in molten lead only once and the thickness of the thin film was about 200μ, and the part 4 was dipped twice to give a thin film thickness of about 400μ. Part 5 was dipped three times, and the thickness of the film was approximately 600μ. The thickness distribution of this lead thin film corresponds to the current density distribution of the lattice body, and has a thickness distribution that is excellent in terms of voltage characteristics. Incidentally, the weight is approximately 1/2 that of a cast grid with the same voltage characteristics, resulting in a significant weight reduction.

[Brief explanation of the drawing]

Fig. 1 is a front view showing the acid-resistant synthetic resin lattice structure used in the present invention, and Fig. 2 shows the process of immersing the lattice structure in molten lead in the manufacturing method of the present invention. B is a schematic diagram of the second immersion state, and C is a schematic diagram of the third immersion state, and FIG. 3 is a front view showing the completed lead-synthetic resin composite grid. 1... Lattice structure made of acid-resistant synthetic resin, 2
... Molten lead, 3... The thin part of the film formed by immersing it in molten lead only once, 4... The intermediate thickness film part that was dipped twice, 5... The thickest part of the film that was immersed three times. be.

Claims (1)

[Claims] 1. A lattice structure made of acid-resistant synthetic resin is immersed in molten lead or lead alloy, or the molten lead or lead alloy is poured onto the lattice structure to form a thin film on the surface of the lattice structure. The method includes immersing or pouring the molten lead or lead alloy around the current collecting ears of the grid structure at least twice, and sequentially shortening the dipping or pouring time from the second time onwards. A method for manufacturing a grid for a lead-acid battery, characterized by forming a lead or lead alloy thin film thicker than other parts by doing so.