JPS5852616Y2 - battery - Google Patents

Description

[Detailed description of the invention] This invention relates to various batteries such as silver oxide batteries, mercury oxide batteries, and manganese oxide batteries, and its purpose is to provide a battery with low internal resistance and excellent discharge performance.

In general, various active materials such as silver oxide, mercury oxide, and manganese oxide are stored inside a battery with a certain thickness, so electrons are absorbed in the active materials in areas far away from the current collector where there is no anode wire, especially at the separator interface. In ferrous oxide batteries, where this tendency is generally strongly exhibited, the internal resistance becomes extremely high, causing a phenomenon in which the voltage suddenly drops temporarily at the beginning of discharge (camel phenomenon), etc. This is a major cause of reduced performance.

For this reason, attempts have been made to improve the conductivity of the layer by incorporating a large amount of a conductive additive such as graphite into the layer of the anode active material, but this has not been effective enough to avoid the above drawbacks. However, the use of a large amount of such a conductive additive reduces the amount of the positive electrode active material, which inevitably leads to a decrease in discharge capacity.

This invention aims to eliminate these drawbacks, and Figure 1 shows a button-type battery of this invention, in which a positive electrode active material press-molded on a pedestal 1 and a conductive aid such as phosphor-like graphite are used. An anode mixture 2 containing an alkali electrolyte is housed at the bottom of an anode wire 3 having a larger diameter than the above mixture 2 injected with an alkaline electrolyte, and the mixture 2 and the cathode terminal plate 4 are filled with zinc powder, A thin film layer 6 of a reducing polymer such as starch, cellophane 7 and nylon is placed between the paste-like cathode mixture 5 containing a cathode active material such as zinc amalgam powder and an alkaline electrolyte, and facing the mixture 2. A separator 9 composed of a liquid absorbing layer 8 such as nonwoven fabric or vinylon mixed paper is interposed, and an annular gasket 10 is interposed between the cathode terminal plate 4 and the anode wire 3 to move the anode wire 3 inward. It tightens and blocks the inside of the battery.

As is clear from this configuration, this invention is such that a thin film layer 6 of a reducing polymer is provided on the surface of the separator 9 facing the anode mixture 2. According to this, the anode active material at the interface of the separator is In particular, if the polymer thin film layer 6 is made of something that dissolves in the electrolyte, such as starch, it will gradually flow to the separator interface by absorption of the electrolyte, and the active material at the interface will be reduced. It is reduced relatively quickly, and this reduction improves the electron conductivity at the interface between the separators and greatly reduces the internal resistance of the battery.

In addition, since this reducing polymer thin film layer 6 faces the anode mixture 2 and is in the form of a thin film, it reduces the discharge capacity because it reduces only the surface of the anode mixture 2 at the separator interface. It does not cause deterioration or generate gas through reduction reactions.

Figure 2 shows a button-type battery A of this invention in which the anode active material is silver oxide and the cathode active material is zinc amalgam, using the separator having the above structure.
This figure shows the discharge characteristics (initial stage) in comparison with the conventional button-type battery B, which uses a separator made of cellophane and a nonwoven fabric layer such as vinylon mixed paper. It can be seen that the camel phenomenon is suppressed due to the good electron conductivity of the separator interface.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing the button-type battery of this invention, and FIG. 2 is a diagram showing the discharge characteristics. 9...Separator, 6...Thin film layer of reducing polymer, A...Battery of this invention, B...
...Conventional battery.

Claims (1)

[Scope of utility model registration request] A thin film layer 6 of a reducing polymer such as starch capable of reducing the anode active material on the surface of the separator 9 facing the anode mixture 2
A battery characterized by being provided with.