JPS59114472A - Apparatus for judging life of hermetically closed lead battery - Google Patents

Abstract

PURPOSE:To perform the life judgement of a negative pole absorbing type hermetically closed lead battery, by measuring a trickle charging current or a floating charging current flowed to a lead battery while comparing the measured value with a reference set value. CONSTITUTION:A charging current flowed to a battery B1 during trickle charging is converted to voltage by a resistor R1 and said voltage is amplified by an amplifier IC1. A peak value is cut by a circuit consisting of a diode D2, a condenser C1 and resistance R14 to average the voltage. The temp. of the battery B1 is detected by a temp. sensor IC4 while charging voltage is detected by a Zenner diode D3 and the compensation of the charging current value when the temp. or the charging voltage is changed is performed by an adder subtractor circuit I2. The amplified value of the charging current and reference voltage are compared by a comparator I3. A thyristor SCR1 for turning ON and OFF a life display lamp D1 is controlled corresponding to the comparison result.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention is used in trickle charge or floating charge conditions to provide reliable and stable power to loads during power outages.
This invention relates to a device for determining the life of a sealed lead-acid battery that absorbs oxygen gas at its negative electrode.

Conventional structure and its problems Conventional sealed lead-acid batteries with negative electrode gas absorption have adopted a sealed method in which the negative electrode plate absorbs the acid-ice gas generated during charging. Because liquid is used,
It was difficult to estimate the capacity by measuring the specific gravity of the electrolyte. Furthermore, many of the batteries that house the battery electrode plates are opaque, and it is nearly impossible to determine the state of deterioration of the electrode plates by visual inspection, so in order to measure the state of deterioration, it is necessary to operate the storage battery under a constant load. The only methods available were to discharge the battery and measure the relationship between the discharge time and the voltage, or to measure the internal resistance, which increases with the state of deterioration.

However, such a capacity test to determine the state of battery deterioration requires a special measuring device, which is meaningless unless it is carried out on a certain regular basis, and the cost of measuring capacity increases. It was difficult to implement this method in sealed lead-acid batteries with negative electrode absorption. Furthermore, the internal resistance measurement method also has the disadvantage that the measurement circuit is complicated and expensive. For this reason, the reliability of the power supply system is maintained by periodically replacing negative-electrode sealed lead-acid batteries used in trickle charge or floating charge states. When is high, the amount of liquid loss and the amount of corrosion of the positive electrode grid increases, and as shown in Figure 1, as the charging current increases,
There was a tendency for the capacity to decrease early, and there was a problem with the reliability of the power supply system.

OBJECTS OF THE INVENTION The present invention overcomes the above-mentioned drawbacks of the prior art. The life deterioration mode of lead-acid batteries that use general lead-antimony alloys is mainly due to corrosion of the positive electrode grid made of antimony alloy and a decrease in capacity due to cell-to-cell variation in the negative electrode, whereas sealed lead-acid batteries with negative electrode absorption The deterioration life mode of the battery uses a lead-calcium alloy that is less prone to self-discharge and lattice corrosion, so such factors are unlikely to cause the life to end, but the amount of electrolyte is comparatively lower than that of ordinary batteries. The main cause is corrosion of the positive electrode grid due to an increase in internal resistance due to evaporation of water in the electrolytic solution or dissipation of gas, and an increase in charging current due to an improvement in the gas absorption ability of the negative electrode plate.

Therefore, in this type of battery, as shown in Figure 1, the increase in charging current due to liquid reduction has a high correlation with capacity, so the trickle charging current and floating charging current are measured and the charging current is measured. The purpose is to provide a highly reliable power supply system by estimating the state of battery capacity deterioration from the value, displaying the storage battery life, and having the battery replaced with a new battery.

Structure of the Invention In order to achieve the above object, the present invention detects the charging current, which increases as the capacity of a negative absorption type sealed lead acid battery used in trickle charging or floating charging, increases as the capacity decreases by converting the voltage using a microresistor and amplifying it. At the same time, this charging current value,
It is characterized by comparing it with a standard setting value set to 3 to 8 times the charging current value of a new battery, and when the charging current becomes larger than the specified value, it displays an indication such as lighting up a life indicator lamp. That is. Note that this charging current value is also affected by changes in battery temperature and charging pressure, and a large charging current flows during charging after a power outage, so corrections for these are necessary.

In this way, the charging current is measured using a simple circuit, and the charging current value lights up a warning lamp indicating a decrease in capacity, and a request to replace the battery with a new one is sent, so it is clear when it is time to replace the storage battery. It is possible to improve the reliability of the power supply system by eliminating troubles such as the power supply being stopped during a power outage due to the lifespan of the storage battery.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 2 shows an example of a circuit configuration in which the charging current value of a negative electrode absorption type sealed lead acid battery during trickle charging is measured and the life span is indicated based on the magnitude of this measured value.

In the figure, an amplifier D2.C1 converts the charging current flowing into the storage battery B1 during trickle charging into voltage using a resistor R1, and amplifies this voltage at an amplification degree set by resistors R2 and R3. cl, R14 is a circuit that cuts and averages the peak value of the charging current so as not to malfunction when ripple is included in the charging current, and the circuit C2 is a temperature sensor circuit C4 that detects the temperature of the storage battery B1. The trickle charging voltage of the storage battery B1 is connected to the Zener diode D3. and by the variable resistor VR1 for setting the reference voltage? R4, R5, R6, R
7 determines the amplification degree, and C3 is an addition/subtraction circuit that corrects the charging current value when the storage battery temperature or charging pressure changes.C3 is a standard determined from the output voltage and charging pressure of the temperature sensor C4. A comparator, T
1 is a transistor that controls the thyristor 5CR1 that lights up the life indicator lamp D1, which is made up of a light emitting diode, etc. SWl is a switch that resets the thyristor 5CR1, and Tr2 is a transistor that controls the large charging current when charging the storage battery after it has been discharged due to a power outage, etc. This transistor is controlled by a timer T so as not to detect it for a certain period of time, and prevents malfunction by not operating the thyristor 5CR1. R
9-R13 indicates resistance.

FIG. 3 shows the relationship between the life indicator 6, the discharge capacity of a negative electrode absorption type sealed lead acid battery, and the measured value of the trickle charge current using the life determination device of the embodiment according to the present invention. The battery had a 12V, 3.0Ah specification, a charging atmosphere temperature of 4o±3°C, and a trickle charging voltage of 14°Ov.

In this way, according to this embodiment, the temperature and charging pressure of the storage battery are also measured at the same time as the measurement of the trickle charging current value to correct the charging current value, and furthermore, when charging after a power outage, a lifespan display is displayed. It has a circuit configuration that does not require any damage, and it is possible to display the reliability of the lifespan.

Effects of the Invention As described above, according to the present invention, the following effects can be obtained.

(1) With a simple circuit configuration, it is now possible to determine the lifespan of negative-electrode absorption sealed lead-acid batteries used in trickle charging and floating charging.

(2) The lifespan determination circuit and display section can be constructed in a small and inexpensive manner, and can be attached to a charger or battery.

(3) Appropriate lifespan determination becomes possible, the time to replace the storage battery becomes clear, and power supply during power outages can be more reliably performed, improving the reliability of the power supply system.

[Brief explanation of drawings]

FIG. 1 is a diagram showing the correlation between charging current, internal resistance, and capacity of a sealed lead-acid battery with negative absorption type in a trickle charge state, and FIG. A charging light detection correction circuit and a lifespan display circuit of a lifespan determination device for a lead-acid battery. FIG. 3 is a diagram showing an example of an operation state diagram of a lifespan determination device according to the present invention. Engineering C1...Amplifier, IC2-...Adder/subtractor, IC3...Comparator, IC
4...Temperature sensor, Trl + Tr2...
・・Control transistor, Dl ・°゛°Light emitting diode for life display, 5CR1・・Sirisk, SWl・・Reset switch, vRl・・・・
...Life display setting variable resistor.

Claims (2)

[Claims] (1)) The target is a sealed lead-acid battery that is used in a J-cycle charging or floating charging state, and the negative electrode absorbs oxygen gas generated from the positive electrode. A life determination device for a sealed lead-acid battery, comprising a measuring circuit and a circuit that compares the measured value with a reference setting value set to 3 to 8 times the initial charging current and displays the battery life. (2) The circuit that displays the battery life by comparing the measured value of the charging current with the reference setting value is a correction circuit for changes in the temperature and charging pressure of the storage battery, and changes in the charging current during charging after a power outage. A life determination device for a sealed lead-acid battery according to claim 1, comprising: