JPH0555452U - Deterioration determination method for lead-acid batteries - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a deterioration determination method for a lead storage battery, which does not need to remove the battery from the circuit and can relatively easily, economically and rapidly determine the deterioration of the battery. [Constitution] In the lead-acid battery used in the floating charging system,
When the average value of the charging current that has flowed to this storage battery for at least a certain period of several days after the transition to floating charging after the completion of the periodical equalization is over a certain multiple of the value when the storage battery is installed. , A method for determining deterioration of a lead storage battery that determines that this storage battery has deteriorated.

Description

[Detailed description of the device]

[0001]

[Industrial application]

 The present invention relates to a method for easily determining the deterioration state of a storage battery in a floating charging system in which a charging device, a load and a storage battery are always connected in parallel and used.

[0002]

[Prior art and its problems]

 In the past, to determine the deterioration of a storage battery, multiple batteries were taken out from the variation in the voltage of a single battery during floating charging or those that had reached the end of their useful life, and they were taken back to the manufacturing plant and various characteristics were measured. Deterioration was judged.

[0003] This method requires a lot of labor for taking out for the investigation, cost of the substitute battery, cost for the investigation, and the like, and most of the storage batteries are often not judged the deterioration state. For this reason, it may not be possible to notice the deterioration of the storage battery, and it may not be possible to back up the important power source, such as during a power outage.

A lead antimony alloy grid is used for the positive electrode plate of the lead acid battery, and during use, antimony in the positive electrode plate is gradually eluted and deposited on the surface of the negative electrode plate. Overvoltage shifts to you. It is well known that the deposition of antimony on the negative electrode has a correlation with aging deterioration, and the terminal voltage of the unit cell decreases in proportion to the adhesion state when charged with a constant current. FIG. 1 is a diagram showing the relationship between the number of years of use of a lead storage battery and the floating charging current when measured under a constant condition of a temperature of 25 ° C. and an applied voltage of 2.18 V / cell.

Normally, when a floating charging method is used, a constant voltage is applied to the storage battery terminal from the charging device, so that the charging current flowing in the storage battery increases in proportion to the aged deterioration as shown in FIG. To do. However, since the charging current that flows in the storage battery during floating charging in an actual power supply device changes depending on the load condition and temperature in addition to the deterioration condition, until now the battery is taken out of the circuit and the temperature is changed by another device. It was found that the measured value was kept constant and exceeded 10 times in the area of deterioration failure. This method is expensive and time consuming, as mentioned earlier.

As shown in FIG. 2, a storage battery normally used as an emergency power source has a charging device, a storage battery, and a load connected in parallel. Here, the charging current value flowing through the storage battery is not constant as shown in FIG. 3 and is changing every moment due to factors such as load fluctuations with the passage of time. For this reason, it is difficult to use that value for comparison even if it is measured at one point.

[0007]

[Means for Solving the Problems]

 The present invention proposes a method of solving these problems and easily performing deterioration determination.The main point is to detect the average value of the charging current flowing in the storage battery during a certain fixed period. However, by looking at how many times this value was compared with the value when the storage battery was installed, we found that deterioration can be determined without taking the battery out of the circuit and measuring it under certain conditions. It is based on.

[0008]

【Example】

 For the pasted lead-acid battery HS-200 type (1 hour rate capacity: 120 Ah) built in the emergency power supply unit, the equal charge that is regularly performed every 6 months from the start of use is completed, and after shifting to floating charge, A For 1 day, B for 7 days, and C for 14 days, calculate the average charging current by dividing the amount of electricity obtained by integrating the charging current flowing in the storage battery during floating charging by the integrated time. This was continued for 7 years. This relationship is shown in FIG.

As can be seen from FIG. 4, since the current accumulated in one day of A after the shift to floating charging is not sufficiently stable, the average charging current is different from the value at the previous measurement. In some cases, the accuracy is inferior as a method for detecting changes in charging current due to battery deterioration, and accurate deterioration determination is difficult.

On the other hand, the value obtained by accumulating C for 14 days is increasing at a constant rate, and the tendency is similar to that excluding the influence of the load shown in FIG. I am doing it. In addition, although the accuracy of B for 7 days is slightly inferior to that of C, it shows a certain tendency.

From this, when the charging current is collected for 14 days or more and the value of the charging current starts to increase rapidly as compared with the time when the battery is installed, or when the value reaches about 10 times. Therefore, the method of determining deterioration can be implemented relatively easily, and the deterioration can be determined with high accuracy. For example, the integrated quantity of electricity (Ah) can be integrated by a coulometer using a solid electrolyte by converting a voltage obtained from a shunt provided in a battery circuit into a current.

In addition, the equal charging cycle is generally performed every 6 months, and in the example of FIG. 1 performed in April and October, the ambient temperature is very similar, so that the influence of temperature appears. However, if it is carried out when there is a possibility that the ambient temperature may have a large influence, such as in February and August, it is possible to compare with the same period of the previous year or to correct the temperature. ..

If the charging current integration period is shortened to one week or several days, the accuracy tends to be deteriorated, but the deterioration factor is determined by setting the current increase factor lower than 10 times. If devised, the deterioration of the battery can be almost determined.

[0014]

[Effect of the device]

 As described above, the deterioration determination method for lead-acid batteries proposed by the present invention makes it possible to determine the deterioration of the battery relatively easily, and it is not necessary to remove the battery from the circuit. The value is great.

[Brief description of drawings]

[Figure 1] Diagram showing the relationship between the number of years of use of lead acid batteries and floating charging current

FIG. 2 is a block diagram of a floating charging method.

FIG. 3 is a diagram showing a time change of a charging current during floating charging.

FIG. 4 is a diagram showing the relationship between the number of years of use of a lead storage battery and the average floating charging current.

Claims (1)

[Scope of utility model registration request] 1. In a lead storage battery used in a floating charging system, an average value of a charging current flowing through the storage battery in a constant period of at least several days after a shift to floating charging after the completion of the periodical equalization is performed. A method for determining deterioration of a lead storage battery, which determines that the storage battery has deteriorated when it exceeds a certain multiple of the value when the storage battery is installed.