JPH0963656A - Method for operating storage battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the occurrence of heat run-away so as to prevent the deterioration of life of a storage battery, by cooling the storage battery when the current value gets over the specified value, when charging a negative electrode absorption system sealed storage battery with a constant voltage constant current. SOLUTION: In a method of charging a negative electrode absorption system sealed storage battery with a constant voltage constant current, the storage battery is cooled by operating a blow fan when the current value of charging gets over the preset fixed value, thus the temperature of the storage battery is restrained from rising by charging. This prevents heat run-away from occurring in the storage battery and the life of storage battery from deteriorating.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for operating a storage battery, and more particularly, to a method for forcibly cooling a cathode absorption type sealed storage battery at a constant voltage and a constant current when the charging current value exceeds a set value. is there.

[0002]

2. Description of the Related Art Cathode absorption sealed rechargeable batteries, such as cathode absorption sealed lead rechargeable batteries, are generally unnecessary by charging by a constant voltage charging system in which the voltage at the end of charging is controlled to a predetermined value. Prevent overcharging.

[0003]

The problem in this case is that the internal current (electrical resistance) of the storage battery decreases as the temperature of the storage battery increases during charging, so that the charging current increases and the temperature of the storage battery increases. It is conceivable that a so-called heat escape occurs, which causes a vicious circle in which the charging current increases and the charging current increases at the same time.

The object of the present invention is to prevent the occurrence of this heat escape and prevent the deterioration of the life due to heat generation.

[0005]

As a charging method for a cathode absorption sealed lead-acid battery, a constant voltage charging method performs capacity recovery after discharging in a short time and appropriately overcharges after almost complete charging. It is one of the excellent methods to control. However, if the temperature of the storage battery becomes high or the control voltage value (constant voltage value) at the time of charging becomes high in this charging method, the phenomenon of thermal escape tends to occur. The increase in the temperature of the storage battery and the increase in the charge control voltage are inseparable from the increase in the charging current value. This is a content that can be understood as a natural result because the energy source that is the driving force for the temperature rise of the storage battery is only the electric power represented by the product of the charging voltage and the charging current. The point of the present invention is to pay attention to this charging current, detect that the charging current exceeds a predetermined value, operate a blower fan by this detection signal, and adopt a method of cooling the storage battery by the generated wind. That is.

[0006]

[Function] It is not appropriate to unconditionally determine the specific predetermined charging current here, and the size (capacity) of the storage battery
Number of storage batteries used in combination, arrangement method of storage batteries,
It is necessary to set individually according to the state of air circulation around the storage battery, the set voltage of the charger (constant voltage control value), and the maximum charging current value of the charger.

Generally, this predetermined value needs to be set to a relatively small value as the capacity increases in terms of the ratio to the capacity of the storage battery. This is because the larger the size of the storage battery, the smaller the heat dissipation area for releasing the heat generated inside the storage battery by charging.

[0008]

EXAMPLES Examples of the present invention will be described below with reference to a method of operating an assembled battery.

Twenty-four vertical cathode absorption type sealed lead-acid batteries with a nominal voltage of 12 V and a rated (20 hour rate) capacity of 24 Ah
One battery pack is constructed by combining the individual batteries and the horizontal three batteries. The assembled battery is housed in a metal cabinet having an internal volume that is about twice the total volume of the assembled battery, and ventilation openings are provided on both sides of the cabinet facing each other, and exhaust air is exhausted through one of these openings. A fan (rated input 30 W) was provided for the. This assembled battery is charged at a constant voltage of 328.8V ± 2.4V at all times except during discharging (current limit: 7.
2A) was performed, and when the charging current exceeded 1.2A, the exhaust fan was operated. The discharge was performed every 3 months at a constant current of 6 A until the terminal voltage of the assembled battery dropped to 252V. The test was performed at room temperature of approximately 15 to 25 ° C.

FIG. 1 shows the number of discharges and the dischargeable time when charging and discharging were repeated by using the storage battery of this example and the storage battery of the comparative example without the cooling fan. . Further, FIG. 2 shows the values of the temperature of the surface of the storage battery which is located in the center of the storage battery row when 24 hours have elapsed after charging after the end of discharge.

As is apparent from FIG. 1, this example has a discharge time (discharge capacity) with the lapse of charging years as compared with the comparative example.
It can be seen that there is little deterioration. It is considered that this is because the temperature rise of the storage battery during charging is smaller in the case of the present embodiment than in the case of the comparative example, as shown in FIG. In addition, the storage battery of the comparative example shows a clear tendency for the battery temperature to rise during charging as the number of years of charging increases, but this phenomenon may cause a temperature to reach an inconvenient temperature. Seem. In comparison, the storage battery of the present embodiment promptly removes the heat generated by driving the cooling fan from the storage battery when the charging current that causes the temperature rise reaches a preset constant value. Therefore, the temperature rise due to the charging of the storage battery can be suppressed.

[0012]

As described above, according to the present invention, when the charging current value exceeds the predetermined value set in advance, the blower fan is operated to forcibly cool the storage battery to prevent the occurrence of thermal runaway and generate heat. It is possible to prevent deterioration of the life of the storage battery due to.

[Brief description of drawings]

FIG. 1 is a diagram showing the relationship between the number of years of charge and the discharge time of a battery.

FIG. 2 is a diagram showing the relationship between the number of years of charging and the battery temperature.

Claims (1)

[Claims] 1. A system for charging a cathode absorption type sealed storage battery with a constant voltage and a constant current, and when the charging current value exceeds a predetermined value, a blower fan is operated to cool the storage battery. How to operate the storage battery.