JP2739360B2 - Manganese dry cell - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial application field) The present invention relates to the inhibition of corrosion of a negative electrode zinc or zinc alloy of a manganese dry battery.

(Prior Art) As a negative electrode material of a manganese dry battery, a zinc can to which a small amount of lead, cadmium or the like is added is generally used because it is relatively stable chemically, has good workability and is inexpensive. However, if it is used as it is, the corrosion of zinc is severe, and the battery after long-term storage tends to deteriorate in performance. Therefore, for a normal manganese dry battery, 0.01 to 0.2 mg / cm per effective area of the zinc can
^{About 2} mercury is added.

(Problems to be solved by the invention) However, manganese batteries containing this amount of mercury are said to not cause environmental pollution even if they are disposed of. However, in a future social environment, it is safer to add no mercury. Alternatively, a mercury-reduced manganese dry battery is required, and the establishment of zinc corrosion prevention technology is indispensable.

The present invention has been made to solve the above-described problem, and has as its object to provide a manganese dry battery in which corrosion of zinc or a zinc alloy used as a negative electrode is suppressed as much as possible.

[Constitution of the Invention] (Means for Solving the Problems) The present inventor has conducted intensive studies in order to achieve the above-mentioned object. By adding a specific amount of chloride, it has been found that corrosion of zinc is suppressed as much as possible without deteriorating the potential of manganese dioxide of the positive electrode, and the present invention has been achieved.

That is, the present invention relates to a manganese dry battery using an electrolytic solution containing a zinc chloride solution and / or an ammonium chloride solution as a main component, wherein the cationic surfactant is present in the battery in an amount of 0.002 to 0.2% by volume based on the electrolytic solution. It is a manganese dry battery characterized by having been made.

The addition range of the cationic surfactant is preferably 0.002 to 0.2% by volume with respect to the electrolytic solution. If the amount is less than 0.002% by volume, the effect of addition is small. However, it is not preferable because the potential deterioration of manganese dioxide of the positive electrode increases.

Further, the addition of the cationic surfactant sufficiently suppresses corrosion in zinc or zinc alloy containing no mercury. However, the same effect can be obtained in zinc-containing mercury or zinc-containing alloy containing a small amount of mercury.

(Action) Regarding the effect of adding the cationic surfactant of the present invention,
It is considered that the cationic surfactant adsorbed on the zinc surface inhibits the hydrogen gas generation reaction, thereby suppressing corrosion.

(Examples) Hereinafter, the present invention is based on Examples, Comparative Examples and Reference Examples,
This will be described in detail.

Examples 1 to 10, Comparative Examples 1 to 4 and Reference Example 1 Using a R20 zinc can, length 5.0 cm x width 9.6 cm x thickness 0.04 cm
And test specimens (with no mercury added) and Hg
So that the zinc, - Cl ₂ solution mercury 0.005 mg / cm ² using a
Two types, one with the surface amalgamated, were subjected to the test. The corrosion test was carried out using an electrolyte having a mass ratio of ZnCl ₂ : NH ₄ Cl: H ₂ O of 26: 3: 71 at a ratio of 60 cc of the electrolyte to one test piece.

The addition amount of the cationic surfactant monoalkyl quaternary ammonium chloride from coconut oil is varied in the range of 0 to 0.2% by volume with respect to the electrolytic solution, and added to the electrolytic solution. The test was performed. (Examples 1 to 10 and Comparative Examples 1 to 4).

For reference, a test piece amalgamated to give 0.2 mg / cm ² -mercury-zinc and without a cationic surfactant was also used for the test. (Reference Example 1) In the evaluation of the corrosion test, weight loss after storage at 45 ° C. for 15 days was measured, and the average weight loss of the three pieces was shown in terms of unit area (mg / cm ² -zinc). Table 1 shows the mercury addition amount, the cationic surfactant addition ratio, and the corrosion weight loss.

Examples 11 to 20, Comparative Examples 5 to 8 and Reference Example 2 As an electrolytic solution, the mass ratio of ZnCl ₂ : NH ₄ Cl: H ₂ O was 10: 2.
A corrosion test was conducted in the same manner as in Example 1 except that a sample of 2:68 was used, and the results are shown in Table 2.

Examples 21 to 30, Comparative Examples 9 to 12, and Reference Example 3 Electrolytes having the same structure as in Example 1 were prepared by adding no mercury as zinc for the negative electrode, and 0.005 mg / cm ^{2 of} mercury.
-Using a solution obtained by adding HgCl ₂ to the electrolyte so as to become zinc, the amount of the cationic surfactant added to the electrolyte,
The amount was varied in the range of 0 to 0.5% by volume, and ten R20 manganese dry batteries were prototyped. This prototype battery was stored at 45 ° C. for 3 months, and the potential deterioration of manganese dioxide was evaluated by the open circuit voltage, and the corrosion effect on zinc was evaluated by the duration of 4Ω continuous discharge up to 0.9 V. (Examples 21 to 30, Comparative Examples 9-1
Four).

As a reference, HgCl ₂ was added to the electrolyte in advance so that the negative electrode became 0.2 mg / cm ² -zinc mercury. Evaluation was made similarly (Reference Example 3). Table 3 shows the mercury addition amount, cationic surfactant addition ratio, open circuit voltage (average value) and 4Ω continuous discharge duration (average value).

Examples 31 and 32 The same composition as in Example 1 was used as the electrolytic solution, and a cationic surfactant was applied to the inner surface of the zinc can at 0.05% by volume with respect to the electrolytic solution (Example 31). .
An R20-type manganese dry battery was prototyped using the one added with 05% by volume (Example 32). Using these dry batteries, the open circuit voltage and the continuous discharge duration of 4Ω were evaluated in the same manner as in Example 21, and the results are shown in Table 3.

Examples 33 to 42, Comparative examples 15 to 20 and Reference example 4 Using an electrolyte having the same composition as in Example 11, a manganese dry battery was prototyped in the same manner as in Example 21, and the open circuit voltage and 4Ω continuous discharge sustained. The time was evaluated (Examples 33-42,
Comparative Examples 15 to 20).

As a reference example, HgCl ₂ was added to the electrolyte in advance so that the negative electrode became mercury 0.2 mg / cm ² -zinc, a manganese dry battery was prototyped in the same manner as above, and the open circuit voltage and 4Ω continuous discharge duration Was evaluated (Reference Example 4).

Table 4 shows the mercury addition amount, cationic surfactant addition ratio, open circuit voltage and 4Ω continuous discharge duration.

Examples 43 and 44 The same composition as in Example 11 was used as the electrolytic solution, and a cationic surfactant was applied to the inner surface of the zinc can at 0.05% by volume with respect to the electrolytic solution (Example 43). .
Example 3 using the addition of 05% by volume (Example 44)
A manganese dry cell was prototyped in the same manner as in 1 and 32.

Using these batteries, open circuit voltage and 4
The continuous discharge duration of Ω was evaluated, and the results are shown in Table 4.

As shown in Tables 1 to 4, when the cationic surfactant was added in the range of 0.002 to 0.2% by volume based on the electrolytic solution, the corrosion of zinc or zinc alloy was significantly suppressed, and in the manganese dry battery, Since the open circuit voltage does not deteriorate much after storage and the discharge duration is extended, corrosion of the zinc can, which is the negative electrode, is significantly suppressed without deteriorating manganese dioxide, which is the positive electrode active material of manganese dry batteries. I understand. Further, it can be seen that the same effect can be obtained not only by adding the cationic surfactant to the electrolytic solution, but also by coating it in the negative electrode zinc can and adding it to the separator.

[Effects of the Invention] As described above, the manganese dry battery of the present invention in which a cationic surfactant monoalkyl quaternary ammonium chloride using a specific amount of coconut oil as a raw material is present in the battery as an amount with respect to the electrolyte, Even when mercury is reduced or no mercury is added, corrosion of zinc or a zinc alloy used as a negative electrode can be significantly reduced without deteriorating manganese dioxide which is a positive electrode active substance, and is of great industrial value.

Claims (1)

(57) [Claims] 1. A manganese dry battery using an electrolytic solution containing a zinc chloride solution and / or an ammonium chloride solution as a main component, wherein a cationic surfactant monoalkyl quaternary ammonium chloride made from coconut oil is contained in the battery. A manganese dry battery wherein 0.002 to 0.2% by volume of the electrolyte is present.