JPH07211330A - Seawater battery - Google Patents

Abstract

PURPOSE:To efficiently use oxygen dissolved in seawater as a cathode oxidizing agent to enhance discharge performance by widening the apparent working surface area of a plate-shaped cathode twice or more that of a pillar-shaped anode. CONSTITUTION:A seawater battery has a cathode 1 produced by cylindrically arranging a steel or iron net or expanded metal sheet or a plurality of these nets or sheets stuck, and a pillar-shaped anode 2 made of magnesium or a magnesium alloy arranged in the center of the cathode 1. The upper end and the lower end of the cathode 1 are fixed to each of circular plate-shaped outer frames 7 made of synthetic resin or FRP directly or through a cathode insulator 8. The upper end and the lower end of the anode 2 are fixed to each of the outer frames 7 through an anode insulator 9. The apparent working surface area of the cathode 1 is made wider twice or more than that of the anode 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a seawater battery, and more particularly to a seawater battery using magnesium or magnesium alloy as a cathode and oxygen dissolved in seawater as an anodizing agent. .

[0002]

2. Description of the Related Art A seawater battery uses seawater as an electrolyte. A typical example of the seawater battery is a silver chloride battery using silver chloride for the anode and magnesium alloy for the cathode, copper chloride for the anode, and magnesium alloy for the cathode. There are various types of batteries, such as copper chloride batteries, lead dioxide for the anode, lead dioxide battery for which the magnesium alloy is used for the cathode, lead chloride for the anode, and lead chloride battery for which the magnesium alloy is used for the cathode. This causes an electromotive force.

The conventional structure of such a seawater battery is shown in FIG.
, A sheet-shaped anode 1 rolled to a thickness of about 0.2 to 0.5 mm and a cathode 2 made of a magnesium alloy plate are made to face each other with a spacer 3 interposed therebetween. It is housed in a battery case 4, and is activated by injecting seawater from a seawater inlet 6 provided in the battery case 4 by immersing it in seawater to activate magnesium hydroxide and hydrogen generated by the reaction. The gas is discharged from the gas outlet 5 provided in the tank 4. In addition, 10 is the anode 1
An anode lead wire electrically connected to the cathode lead wire 11;
Is a cathode lead wire electrically connected to.

On the other hand, a dissolved oxygen battery in which oxygen dissolved in seawater is used as an anodizing agent and magnesium or magnesium alloy is used in the cathode is also known as a kind of seawater battery.

The conventional structure of such a seawater battery is shown in FIG.
As shown in FIG. 3, a spacer 3 is interposed between an anode 1 made of a copper net and a cathode 2 made of a magnesium alloy plate so as not to become a resistance when passing seawater, and they are opposed to each other.
It is stored in a container, and is immersed in seawater to make the battery case 4
Seawater is injected from the seawater inlet 6 provided in the fuel cell, an electromotive force is generated by a redox reaction on the surface of the anode 1, and hydrogen generated by the reaction is discharged from a gas outlet 5 provided in the battery case 4. It was done.

Among the above-mentioned seawater batteries, the silver chloride battery has the advantages that it has excellent discharge performance at large current density and has a long discharge duration, but it has the disadvantage that the silver chloride used for the anode is expensive. Although copper chloride used for the positive electrode of a copper battery is not as expensive as silver chloride, it has the disadvantage that the discharge performance at high current density and the discharge duration time are short, and the lead dioxide used for the positive electrode of a lead dioxide battery is cheap. Discharge duration is short, and lead chloride batteries use lead chloride for the anode at a low price, but have short discharge duration and low discharge voltage.

The above-mentioned dissolved oxygen battery can have a long discharge duration, but the amount of oxygen dissolved in seawater is as small as about 3% and the surface area of the anode 1 facing the cathode 2 is small, so that a small amount of current is required. The disadvantage is that it is limited to the discharge of.

[0008]

As described above, the seawater battery is used properly according to various uses, but it has excellent discharge performance at a large current density and a long discharge duration.
There was a problem that it was difficult to get something that was cheap.

[0009]

In order to solve the above-mentioned problems, the present invention arranges a columnar cathode in the center and a plate-shaped anode around the cathode in a cylindrical shape, and dissolves it in seawater. Is used as an anodizing agent, the cathode is oxidized by the anodizing agent, and a seawater battery for reducing the anodizing agent to obtain electromotive force, wherein the plate-shaped anode It is characterized in that the anode is arranged around the cathode so that the apparent working area is at least twice the working area of the columnar cathode.

[0010]

Therefore, according to the present invention, since the anode is arranged around the cathode so that the apparent active area of the plate-shaped anode is more than double the active area of the columnar cathode, Dissolved oxygen can be effectively used as an anodizing agent, and discharge performance can be improved.

[0011]

EXAMPLES The present invention will be described below based on examples.

FIG. 1 is a perspective view of a seawater battery according to the present invention, in which parts having the same functions as those in FIGS. 3 and 4 are designated by the same reference numerals.

In FIG. 1, reference numeral 1 is a net made of copper or iron, an anode in which one or more expanded metals are stacked and arranged in a cylindrical shape, and 2 is magnesium or a magnesium alloy arranged in the center of the cylindrical anode 1. A columnar cathode made of a metal, and the upper and lower ends of the anode 1 are connected to a metal disk-shaped outer frame 7 via an anode insulator 8 or made of synthetic resin, F
It is directly attached to a disc-shaped outer frame 7 made of RP, and the upper and lower ends of the cathode 2 are attached to the outer frame 7 via a cathode insulator 9. Reference numeral 10 is an anode lead wire electrically connected to the anode 1, and 11 is a cathode lead wire electrically connected to the cathode 2.

As the battery of the present invention described above, a columnar cathode 2
A magnesium rod with a radius of 0.5 cm is used for the anode, and the anode 1 made of a copper net is arranged in a cylindrical shape at a position 2.5 cm from the center, and the apparent working area of the anode 1 is 5 times that of the cathode 2. As a conventional battery, a battery having the same weight as the cathode 2 of the battery of the present invention and an anode 1 having the same area as that of the cathode 2 with a weight of 0.5 are provided via a spacer 3.
Each of them was made to face each other at an interval of mm, and each was immersed in seawater having a concentration of 3% and discharged at 10 mA. As shown in FIG. 2, the discharge voltage of the battery of the present invention was the same as that of the conventional battery. It was found that the discharge duration was higher than the voltage and the discharge duration of the battery of the present invention was 1.5 times the discharge duration of the conventional battery. Here, the apparent working area of the anode 1 is the surface area of the anode 1 on the assumption that the oxidation-reduction reaction is performed on the surface thereof.

Next, 1.0 cm, 1.5 cm, 3.5 c from the center of the columnar cathode 2 in the battery of the present invention described above.
The anode 1 made of a copper net is arranged in a cylindrical shape at a position of m and 5.0 cm, and the apparent working area of the anode 1 is made twice, 3 times, 7 times and 10 times as large as that of the cathode 2. Were produced and discharged under the above-mentioned conditions, all of them were superior in discharge performance to the conventional battery, but those in which the apparent working area of the anode 1 was twice that of the cathode 2 had a discharge duration time. It was found that the discharge voltage was slightly lower when the apparent working area of the anode 1 was 10 times the working area of the cathode 2.

It is considered that the former is due to insufficient supply of seawater in which oxygen as an anodizing agent is supplied, and the latter is due to increased electric resistance of seawater.

From the above results, it is understood that in the battery of the present invention, the apparent working area of the plate-shaped anode should be twice or more, preferably 3 to 10 times the working area of the columnar cathode.

In the above-mentioned battery of the present invention, a net made of copper or iron or expanded metal is used as the anode 1, but a copper plate or an iron plate is used to provide a hole for seawater to flow in and out of the outer frame 7. In addition to copper and iron, a metal having a relatively low ionization tendency such as platinum, gold, silver and nickel and an alloy thereof can be used.

Further, in the above-mentioned battery of the present invention, although magnesium or magnesium alloy is used for the cathode 2, a metal having a relatively large ionization tendency such as aluminum, zinc and lead, or an alloy thereof can also be used.

[0020]

As described above, according to the present invention, by increasing the apparent working area of the plate-shaped anode, it is possible to efficiently carry out the redox reaction with oxygen in the seawater, which is a kind of seawater battery. The discharge voltage of the dissolved oxygen battery can be increased and the discharge duration can be lengthened.

In the present invention, the anode 1 is mounted between the upper and lower ends of the anode 1 and the outer frame 7 via the anode insulator 8. However, the reaction locally proceeds at the cathode 2 close to the outer frame 7. Therefore, the discharge voltage can be further stabilized.

[Brief description of drawings]

FIG. 1 is a perspective view of a seawater battery of the present invention.

FIG. 2 is a diagram comparing the discharge performances of the battery of the present invention and a conventional battery.

FIG. 3 is a cross-sectional view of a conventional seawater battery.

FIG. 4 is a cross-sectional view of a conventional seawater battery (dissolved oxygen battery).

[Explanation of symbols]

 1 Anode 2 Cathode 3 Spacer 4 Battery case 5 Gas outlet 6 Seawater inlet 7 Outer frame 8 Anode insulator 9 Cathode insulator 10 Anode lead wire 11 Cathode lead wire

Claims (1)

[Claims] 1. A columnar cathode is disposed in the center, and a plate-shaped anode is disposed in a cylindrical shape around the cathode, and oxygen dissolved in seawater is used as an anodizing agent. A seawater battery that oxidizes the cathode by, and reduces the anodizing agent to obtain electromotive force, wherein the apparent working area of the plate-shaped anode is relative to the working area of the columnar cathode. A seawater battery characterized in that an anode is arranged around the cathode so as to be more than doubled.