JPH02273036A - Hybrid battery - Google Patents

Abstract

PURPOSE:To permit the charging of a battery with a big current by a method wherein a capacitor, capable of accumulating an electric energy more than a secondary battery capable of charging and discharging, is connected in parallel while the charging current from the capacitor is controlled based on the specification of the secondary battery. CONSTITUTION:A big capacity capacitor 2, capable of accumulating more amount of energy than a secondary battery 1, is connected in parallel to the secondary battery 1 through a reverse current precluding diode 4 and a current limiting circuit 5, connected in parallel to the diode 4, while the terminals of the capacitor 2 are utilized as external terminals. The current limiting circuit 5 limits a current higher than a charging current determined in the specification of the secondary battery 1. Both terminals of the capacitor 2 are connected to an external power source to charge the capacitor with a big current while the Zener diode of a monitor circuit 3 is put ON when the voltage of the Zener diode 31 has arrived at the Zener voltage thereof whereby a voltage is generated in the diode 32 and charging is stopped. Subsequently, the secondary battery 1 is charged with a current, limited by the current limiting circuit 5 based on the specification of the secondary battery and conducted through the capacitor 2. According to this method, the overcharging of the secondary battery may be prevented even if the big current charging of a short time is effected and the long life of the battery may be kept.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a hybrid battery with improved charging characteristics.

(Prior Art) Lead-acid batteries, which have a large electromotive force and are chargeable/dischargeable secondary batteries, have been widely used as power sources for B-operation for a long time.

As a charging control device for this type of secondary battery, a temperature sensor whose terminal voltage changes depending on the temperature is placed close to the battery, detects the temperature difference before and after the battery is fully charged, and charges the battery based on the temperature difference. A proposal to control the
It is disclosed in the publication No.-3537.

(Problems to be Solved by the Invention) In the above-mentioned lead-acid battery, dilute sulfuric acid is used as the electrolyte, lead or lead oxide is used as the electrode, and charging and discharging are performed by the chemical effects of these.

For this reason, rapid chemical action cannot be expected, and when charging, for example, a small current of about 10 hours is supplied to the battery for a long time to chemically change the electrodes. There is a risk of heat generation and deformation of the electrodes, resulting in damage.

In addition, in the proposal shown in the above-mentioned publication, control is performed based on the temperature difference before and after fully charging the battery to be charged.
If the charging current is so small that the temperature rise is dissipated to the outside, the temperature difference cannot be detected and there is a problem of overcharging.

The present invention was made in view of such problems,
The purpose is to shorten charging time and provide a hybrid battery that can be supplied with a large current without any problems.

(Means for Solving the Problems) According to the present invention, there is provided a secondary battery that can be freely charged and discharged through chemical change, a capacitor that can store a larger amount of electrical energy than the secondary battery, and specifications of the secondary battery. A hybrid battery is provided, comprising: current control means for controlling a charging current from a capacitor based on , and in which both terminals of the capacitor are used as external terminals.

(Function) In the present invention, a secondary battery and a large capacitance capacitor are connected via a current control circuit for charging the secondary battery, and when charging from an external power source, a large current is applied to the capacitor in a short time. After charging and storing, the stored electrical energy is used to charge the battery over time based on the specifications of the secondary battery.

(Example) Next, an example of the present invention will be described in detail using the drawings.

FIG. 1 is a block circuit diagram showing one embodiment of the present invention, and FIG. 2 is a circuit diagram showing an example of the current control circuit.

In these drawings, reference numeral 1 denotes a secondary battery, such as a lead-acid battery, which has electrodes and an electrolyte and is charged and discharged by chemical action, and is of a leak-proof type in consideration of portability. ing.

2 is a large-capacity capacitor, which is a large-scale electric double layer capacitor used as a backup power source for memory in electronic devices. More than the quantity is used.

3 is a charge monitor, in which a series circuit of a constant voltage diode 31 and a light emitting diode 32 is connected between both terminals of the capacitor 2, and the Zener voltage of the constant voltage diode 31 is equal to the terminal voltage of the secondary battery 1 at the end of charging. , a voltage set by adding a predetermined voltage to a voltage based on a voltage drop at a junction of a semiconductor element of a current control circuit, which will be described later, is used.

Therefore, when the capacitor 2 is charged, when its terminal voltage reaches the above-mentioned Zener voltage, the constant voltage diode 31 becomes conductive and current flows through the light emitting diode 32, which notifies by emitting light that the capacitor 2 is sufficiently charged. It is something to do.

A diode 4 is a unidirectional element, and is connected between the ten terminals of the battery 1 and the capacitor 2, with the direction in which current flows from the battery 1 as the forward direction.

A current control circuit 5 whose circuit is shown in FIG. 2 is connected in parallel to the diode 4.

In Figure 2, Q is an NPN type transistor, its collector is connected to the cathode of diode 4, its emitter is connected to the anode via a charging current control resistor Rc, and the base circuit is connected between both terminals of capacitor 2. It is connected via a diode D to the connection point of the pixel element of the series circuit of the connected resistor R and thermistor TH. The thermistor TH is a thermistor with reverse characteristics, and is placed close to the secondary battery 1 and serves as a sensor for detecting battery temperature. The base voltage of the transistor Q is controlled so that charging is performed in accordance with the temperature characteristics.

Next, the operation of this embodiment configured as described above will be explained.

The 10th and 1st terminals of the capacitor 2 are used as external terminals and are connected to an external power source capable of supplying a large current during charging.

Although it varies depending on the electrical characteristics of the capacitor 2 and the internal resistance of the external power supply, when the capacitor 2 is charged in a very short time, its terminal voltage reaches the Zener voltage of the voltage regulator diode 31, and as a result, The light emitting diode 32 is energized and emits light.

At this point, the connection with the external power source is cut off, but the charge stored in the capacitor 2 is supplied to the secondary battery 1 via the transistor Q of the current control circuit 5 and the control resistor Re, and is controlled by these resistance values. Charging of the secondary battery 1 is performed gradually using a predetermined current value.

Furthermore, since a thermistor TH that detects the temperature of the secondary battery 1 is connected to the base circuit of the transistor Q, current flows from the capacitor 2 until it reaches full charge according to the characteristics of the secondary battery 1, which changes depending on the temperature. will be supplied.

Next, when the hybrid battery of this embodiment is discharged, power is supplied from the secondary battery 1 via the diode 4 and directly from the capacitor 2 to the load connected between the child terminal and one terminal. .

Although the present invention has been described above with reference to the above embodiments, various modifications can be made within the scope of the gist of the present invention, and these modifications are not excluded from the scope of the present invention.

(Effects of the Invention) According to the present invention, a chargeable and dischargeable secondary battery and a large capacitance capacitor are connected using a charging current control circuit based on the specifications of the secondary battery. Even if a large current is passed from an external power source, the capacitor is first charged without the risk of damage, and then the secondary battery is charged, as the charging current is controlled to an appropriate value and charging is controlled based on temperature characteristics. , there is an effect that overcharging does not occur and therefore a long life of the secondary battery can be obtained.

[Brief explanation of drawings]

FIG. 1 is a block circuit diagram showing one embodiment of the present invention, and FIG.
The figure is a circuit diagram showing an example of the current control circuit. DESCRIPTION OF SYMBOLS 1... Secondary battery, 2... Capacitor, 3... Charge monitor, 5... Current control circuit, Re... Control resistor.

Claims (3)

[Claims] (1) A secondary battery that can be freely charged and discharged through chemical changes, a capacitor that can store more electrical energy than the secondary battery, and a current that controls the charging current from the capacitor based on the specifications of the secondary battery. and a control means,
A hybrid battery characterized in that both terminals of the capacitor are used as external terminals. (2) The hybrid battery according to claim 1, wherein the current control means includes compensation means for compensating for temperature-terminal voltage characteristics of the secondary battery. (3) The hybrid battery according to claim (1), wherein the capacitor is an electric double layer capacitor.