JPS6335402Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an improvement of a measuring electrode body for the purpose of measuring the discharge state of a lead-acid battery whose positive electrode plate constituting an electrode plate group contains antimony.

When measuring the specific gravity, etc. of conventional lead-acid batteries using electrodes, Utility Model Registration No. 871995 (Utility Model Registration No. 871995
A measuring device has been proposed that includes an electrode assembly in which a detection electrode made of lead dioxide and a standard electrode made of lead dioxide immersed in a reference liquid are integrally provided in a container body. However, a drawback of such measuring devices is the difficulty in keeping the concentration of the reference solution in the standard electrode constant over a long period of time. In other words, there is no problem when used for a short period of time at normal temperatures, but when used for many years or at high temperatures,
The charging current required to keep the electrode potential constant and the evaporation rate due to temperature cannot be ignored. Therefore, it is necessary to adjust the reference solution of the standard electrode at regular intervals. In addition, a lead dioxide positive electrode and a lead negative electrode, which are placed in the electrolyte and are always maintained at a constant potential or higher during charging, are placed at the bottom of the container body to prevent changes in the electrolyte concentration of the lead-acid battery to be measured due to charging and discharging. A device has been proposed that measures the potential difference between two electrodes using an electrode body that is integrally provided. In this device, the lead negative electrode that constitutes the electrode body together with the lead dioxide positive electrode is charged as described above in the lead-acid battery, and antimony eluted from the positive electrode plate of the lead-acid battery is deposited on the lead negative electrode of the electrode body. The potential of the negative electrode has the disadvantage that it becomes increasingly noble as the years of use pass.

The present invention eliminates the above-mentioned drawbacks by adsorbing antimony eluted from the positive electrode plate of the electrode plate group of the lead-acid battery to be measured on an adsorbent provided on the surface of the electrode liquid side of the lead negative electrode of the electrode body. The purpose is to measure the electrolyte concentration of a lead-acid battery by keeping the potential of the lead negative electrode of the electrode body constant even during use for a period of time.

1 is a container body made of synthetic resin, such as polyethylene, polyvinyl chloride, acrylonitrile butadiene styrene, etc., which has a negative electrode 2 made of activated lead and a positive electrode 3 made of lead dioxide in the lower peripheral part;
4 is a lid made of synthetic resin, such as polyethylene, polyvinyl chloride, acrylonitrile, butadiene, styrene, etc.; 5 and 5' are negative electrodes 2 and positive electrodes 3;
These are pole terminals for electrically connecting the lead wires 6 and 6' made of copper or the like, respectively, and made of lead or platinum. 7 is a filler made of acid-resistant, oxidation-resistant, insulating synthetic resin, such as epoxy resin, polyester resin, etc., to prevent sulfuric acid from penetrating into the lead wire; an electrolyte flow port 10 for bringing the positive electrode 3 into contact with the electrolyte;
9 is a conventional electrode body composed of members 1 to 8 and 5', 6' and 10; A microporous synthetic resin film-like adsorbent containing phenolic resin that generates a chelate compound with antimony eluted from the positive electrode plate of the electrode group 13 of the lead-acid battery to be measured and inactivates the antimony. It is attached to the container body 1 by heat welding so as to cover the surface portion on the electrolyte side. This adsorbent 11 is made by adding about 5 to 10% by weight of Ferrer resin powder to polyethylene resin powder,
Furthermore, mineral oil is added and mixed, heated and melted to form a film, and then the mineral oil is eluted with an aqueous trichlorethylene solution to obtain an adsorbent 11 having a large number of ion-permeable micropores. . 9A is an electrode body of the present invention composed of members 1 to 8 and 5', 6', and 10, 11, 12 is a battery case, 13 is a battery group, 14 is an electrolytic solution, and 15 is an electrode body for measuring the positive and negative electrode potentials. It is a meter that

An example of actual measurement of the discharge state of a lead-acid battery using the electrode body 9A of the present invention will be explained with reference to FIG. 4. FIG. 4 shows changes in the battery voltage A and the electrode body voltage B according to the present invention as the discharge progresses when a commercially available 12V30Ah lead-acid battery is discharged at a current of 5A. In general, the potential of the positive electrode active material lead dioxide shows a linear change in response to a change in sulfuric acid concentration, while the negative electrode active material lead also changes approximately linearly in response to a change in sulfuric acid concentration, but the change is minute. These positive,
The purpose is to measure the linear potential change due to the sulfuric acid concentration at the negative electrode. The actual measurement results, as shown by straight line B, vary linearly as the amount of discharge increases. Therefore, by reading the potential difference between the measuring electrodes, it is possible to know the discharge state of the lead-acid battery. On the other hand, the electrode body 9A needs to maintain its electrode potential above a certain voltage, and is charged with a current that is about 1/1000 of the electrode capacity. Therefore, a part of the dissolved antimony in the electrolyte of the storage battery to be measured moves toward the negative electrode 2 of the electrode body 9A, and is adsorbed by the adsorber 11 of the electrode body 9A shown in FIG. It doesn't change, but
The conventional electrode body 9 shown in FIG. 1 tends to deposit on the negative electrode 2 and make the potential of the negative electrode 2 noble. Therefore, the voltage of the electrode body 9A shown in FIG. 2 in the present invention at a constant concentration does not change during the life of the storage battery to be measured, whereas the voltage of the electrode body 9A shown in FIG. Changes during the period. The tendency is shown in Figure 5. In FIG. 5, A is a product of the present invention and B is a conventional product. The life test in Fig. 5 was conducted in accordance with the JIS standard test method.

When actually measuring using the electrode body 9A of the present invention, appropriate modifications can be made to the detection circuit and the meter 15 portion to facilitate visual inspection. For example, insert a reverse battery of about 2V into the detection circuit,
By setting the operating range of the meter 15 to 0 to 200 mV, it is possible to read capacitance changes with higher accuracy.

As mentioned above, the present invention has great practical value as it is a simple means for stably detecting changes in the electrolyte concentration of a battery to be measured over a long period of time, and has a simple structure.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing a conventional electrode body, FIG. 2 is a sectional view showing an embodiment of the electrode body in the present invention,
Figure 3 is a cross-sectional view showing the electrode body shown in Figure 2 attached to the lead-acid battery to be measured, and Figure 4 is the relationship between the discharge time and voltage change of the lead-acid battery to be measured, and the voltage change of the electrode body in the present invention. FIG. 5 is an explanatory diagram showing the tendency of the voltage value of the electrode body of the present invention and the conventional method in a fully charged state as the cycle of the lead-acid battery to be measured progresses. 1 is a container body, 2 is a negative electrode, 4 is a lid, 9A is an electrode body, 11 is an adsorbent, and 13 is a group of electrode plates.

Claims (1)

[Scope of utility model registration request] A lead acid battery containing antimony as the positive electrode plate constituting the electrode plate group has a lead dioxide positive electrode and a lead negative electrode, which are always maintained at a potential above a certain level during charging, placed in a storage battery electrolyte at the bottom of the container that hangs down from the lid into the battery. An electrode body that is placed so as to be immersed in the electrolyte to measure the concentration of the electrolyte as a potential difference between the two electrodes, and an antimony adsorbent made of a microporous synthetic resin containing a phenolic resin is provided on the surface of the lead negative electrode that is in contact with the electrolyte. Electrode body for measuring the concentration of lead-acid battery electrolyte.