JPS6280973A - Monoblock sealed lead-acid battery - Google Patents

Abstract

PURPOSE:To increase energy density by forming a half monoblock battery jar in which a grid and a connecting conductor are fixed to a side wall and a partition of the battery jar during injection molding, and joining the two half battery jars to assemble a battery. CONSTITUTION:A half monoblock battery jar is formed by joining together grids a adjacent two cells through a connecting conductor 7, and fixing the grid 6 and the connecting conductor 7 with a side wall 2 and partition 5 during injection molding, and two half monoblock battery jars are joined to assemble a battery. An injection gate for molten plastic in injection molding of the battery jar is mounted in the fixing part of a grid 10 and the battery jar side wall. Since molten plastic injected from the injection gate pushes the grid against a mold 8, a trouble that the whole surface of the grid is covered with plastic entered between the grid and the mold is prevented. Thereby, the battery having compact and thin dimension, steady performance, high energy density, and low man-hour can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION FIELD OF INDUSTRIAL APPLICATION This invention relates to an improvement in a small monoblock sealed lead acid battery that eliminates a flowing electrolyte.

Conventional technology and its problems The demand for small sealed lead-acid batteries has increased with the expansion and popularization of portable devices, and recently there has been a particularly strong demand for miniaturization, improvement in energy density, and cost reduction.

Conventional batteries are made by filling a grid with paste, then aging and drying it, forming a group of electrode plates using chemically formed and dried electrode plates as necessary, and inserting this into an injection-molded battery case to connect the cells. The battery case and lid were connected. In this case, it was difficult to make the battery smaller and thinner because of the two steps of forming the battery case, first inserting the electrode plate group into the battery case. Of course, the former is because if the core is thin, it will move due to the pressure of the molten plastic during injection molding.
The latter is because it is difficult to insert the thin element through the thin opening of the container.

In addition, a single cell battery has been proposed that combines two half-split battery cases with a structure in which a root-like collector is fixed and an active material is adhered to it, but the adhesion between the current collector and the positive electrode active material is Not only is it difficult to maintain, but the load of portable equipment is 6 to 12
In the case of V, since 3 to 6 cells are required, the mass and volume of terminals and inter-cell connections become large, resulting in a disadvantage that the energy density becomes small.

Means for Solving the Problems The present invention is a half-split product in which the grids of two adjacent cells are integrated via a connecting conductor, and the grid and connecting conductor are fixed to the side walls and partition walls of the battery case during injection molding. By adopting a structure in which two block Ti tanks are joined, and in particular by providing an injection gate for molten plastic in the injection molding of the battery case at the fixed part between the grid and the side wall of the battery case, problems such as those described above in monoblock sealed lead-acid batteries can be solved. This is an attempt to resolve the issue.

Embodiment FIG. 1 is a diagram for explaining the structure of a monoblock sealed lead-acid battery according to the present invention, and FIG. 2 is a longitudinal cross-sectional view of a main part showing a state during injection molding of a battery case. In the figure 1
2 is a half-split injection cell for 3 cells, 2 and 2' are the side walls, 3 is the bottom of the 74 tank, 4 is the inner lid, and 5 is the partition wall. Reference numeral 6 denotes a lattice which is integrated with the lattice 6' of an adjacent cell through a connecting conductor 7. The grid 6 is fixed to the battery case side wall 2, and the grid 6' is fixed to the battery case side wall 2'. As shown in FIG. 2, the two are fixed by fitting a grid and a connecting conductor between the injection molds 8 and 9, and then injection molding molten thermoplastic plastic. The injection gate 10 at this time is provided at a fixed portion between the grid and the side wall of the battery case. Reference numeral 10' in FIG. 1 is a portion facing the injection gate 10 at the intersection of the crosspieces of the grid.

Since the molten plastic snack injected from the injection gate presses the grid against the mold 8, it is possible to prevent plastic from flowing between the grid and the mold and covering the entire surface of the grid. This is important for improving the electrical bond between the active material and the grid.

A half-split injection tank 1 to which the grid and connecting conductors are fixed is filled with positive electrode and negative electrode pastes. Naturally, the polarities of the pastes of adjacent cells are different.

Two half-split monoblock battery containers filled with paste are
The positive electrode plate and the n-electrode plate are opposed to each other with a porous separator interposed therebetween, and they are joined by ultrasonic waves or heating using a hot plate. FIG. 3 is a perspective view showing the monoblock sealed lead-acid battery of the present invention thus completed. In the figure, 11 is a joint between the battery cases 1 and 1', and 12 is an exhaust valve.

Effects of the invention The monoblock sealed lead-acid battery according to the invention has the following effects:
It has its features.

B. The battery can be made thinner and the degree of pressure on the electrode plate surface can be increased.

B. No heating or other operations are required for cell connection.
Easy to maintain airtightness and requires less man-hours.

C. The surface of the grid fixed to the side wall of the battery case and protruding into the cell is not excessively covered with plastic, and good electrical bonding between the active material and the grid can be maintained.

From the above effects and features, it is possible to achieve smaller and thinner batteries, stable performance, improved energy density, and reduced man-hours.

[Brief explanation of drawings]

Fig. 1 is a diagram for explaining the structure of a monoblock sealed lead-acid battery according to the present invention, Fig. 2 is a vertical cross-sectional view of main parts showing the state of the battery case during injection molding, and Fig. 3 is a diagram according to the present invention. FIG. 1 is a perspective view showing a monoblock sealed lead acid battery. 1...Half-split injection tank, 2.2'...
Battery case side wall, 5... Partition wall, 6.6'... Grid, 7...
・Connection conductor, 8, 9... Injection mold, 10
... Injection gate = - + j / Storehouse 1 Figure d O Z eye

Claims (1)

[Claims] 1. A half-split product in which the grids of two adjacent cells are integrated through a connecting conductor, and the grid and connecting conductor are fixed to the side wall and partition wall of the battery case during injection molding. A monoblock sealed lead-acid battery that eliminates the need for a fluid electrolyte and has a structure in which two block batteries are joined together. 2. The monoblock sealed lead-acid battery according to claim 1, wherein an injection gate for molten plastic in injection molding of the battery case is provided at a fixed portion between the grid and the side wall of the battery case.