JPH0775457B2 - -ΔV charging controller - Google Patents

Description

TECHNICAL FIELD The present invention relates to a charging control device, and more particularly to a charging control device using the −ΔV method.

[Prior Art] Conventionally, in a charger that performs −ΔV detection during rapid charging and switches to trickle charging, a certain overcurrent does not occur until the object to be charged is used after the rapid charging is completed. Trickle charging in which a small current is continuously supplied is performed to compensate for the internal consumption current of the object to be charged and the self-discharge current of the battery to prevent the battery from discharging.

[Problems to be solved] However, in the case of a wireless device in which only the receiving circuit is turned on during charging, the internal current consumption changes depending on the state of the external radio wave and whether or not self is called. There is also.

When such a thing is trickle charged, the discharge amount may be larger than the charge amount in some cases, and the battery may be substantially in a discharged state.

As an example, when the trickle charge current is 3% of the full charge capacity and the discharge current is 0% minimum, 20% maximum, and 13% on average, as shown in FIG. After 10 hours, it will be completely discharged.

Also, even if you try to use it after 8 hours, its battery capacity is
Only 20% is left.

In order to prevent the above situation, if the trickle charge current is increased, for example, if it is set to 20%, if the current consumption is reduced to about 0% on average due to the state of radio waves, the battery is overcharged, A long time will shorten the battery life.

Therefore, an object of the present invention is to solve the above-mentioned problems of the related art, to shorten the life of the battery, and to always use the battery in a good charge state at the time of use. To provide a device.

[Means for Solving Problems] In order to achieve the above-mentioned object, a −ΔV type charge control device of the present invention includes a quick charging circuit for performing a quick charge on an object to be charged, and a trickle charge for the object to be charged. A switch provided between the trickle charging circuit, the object to be charged, and the quick charging circuit and the trickle charging circuit for selectively connecting the quick charging circuit or the trickle charging circuit to the object to be charged. And the electric power to the charged object is -Δ
When the V characteristic is indicated, a switching signal is sent to the switching device to connect the object to be charged and the trickle charging circuit −Δ
The V detection circuit and the state of the switching device are monitored, and when the trickle charging is continued for a predetermined time according to the object to be charged, a switching signal is sent to the switching device to connect the object to be charged and the trickle charging circuit. And a timer for switching the connection between the connection between the charging object and the quick charging circuit.

[Examples] Hereinafter, the present invention will be specifically described with reference to the illustrated examples.

FIG. 1 is a block circuit diagram of an embodiment of a −ΔV type charge control device of the present invention.

In the figure, 1 is a rapid charging circuit, 2 is a trickle charging circuit, and 3 is a switch, which selects and outputs the outputs of the rapid charging circuit 1 and the trickle charging circuit 2.

Reference numeral 4 denotes a −ΔV detection circuit, which outputs a switching signal to the switching device 3 when the output shows a −ΔV characteristic to control switching from quick charging to trickle charging.

Reference numeral 5 denotes a timer, which monitors the state of the switch 3 and sends a switching signal to the switch 3 to the quick switch when trickle charging continues for a certain time or longer.

The −ΔV type charge control device described above operates as follows.

Now, in the case of rapid charging, when the charging is completed (fully charged) and its output drops according to the −ΔV characteristic, −
Detection is performed by the ΔV detector 4, and the switching device 3 is switched to select the output of the trickle charging circuit 2 instead of the output of the quick charging circuit 1.

The trickle charge current in this case is 3% of the full charge current capacity.
And the average discharge current is the same as in the conventional example shown in FIG.
At 13%, as shown in FIG. 2, it can be seen that the charge capacity decreases to 50% after 5 hours from full charge.

Here, if the timer 5 of FIG. 1 is set to, for example, 5 hours of continuous trickle charging in accordance with the power consumption of the object to be charged, the timer 5 informs the trickle charging from the switch 3. Is continuously received for 5 hours, and the switching device 3 is controlled so as to switch to the quick charging by the time up of itself.

Therefore, the output of the switching device 3 becomes a rapid charge, and -ΔV
Rapid charging is performed until detection is made.

As described above, according to the present embodiment, when the trickle charging is continuously performed for the predetermined time after the completion of the quick charging, the time setting of the timer 5 controls the switching to the quick charging again after the elapse of the certain time. ing.

As a result, for example, even if a discharge phenomenon occurs that is larger than the trickle charge amount during trickle charging, the battery life is shortened or the battery life is shortened because the battery is automatically switched to quick charge at a certain time. It is possible to reliably prevent a situation where the battery is not in a sufficiently charged state at times.

The present invention is not limited to the above embodiment,
Various modifications can be made within the scope of the present invention.

[Effects of the Invention] As described above, according to the present invention, there is an effect that the battery can always be kept in a good charge state without shortening the life of the battery.

[Brief description of drawings]

FIG. 1 is a block circuit diagram showing an embodiment of a −ΔV type charge control device of the present invention, FIG. 2 is a characteristic diagram showing the charge capacity of a battery when the charge control device of the present invention is used, and FIG. FIG. 4 is a characteristic diagram showing a charge capacity of a battery by a conventional charge control device. 1 ... Rapid charging circuit 2 ... Trickle charging circuit 3 ... Switching device 4 ...- ΔV detection circuit 5 ... Timer

Claims (1)

[Claims] 1. A quick charging circuit for rapidly charging an object to be charged, a trickle charging circuit for trickle charging the object to be charged, the object to be charged, the quick charging circuit and the trickle charge. A switch provided between the circuit and a circuit for selectively connecting the quick charging circuit or the trickle charging circuit to the object to be charged; and the switching when electric power to the object to be charged exhibits -ΔV characteristics. A switching signal to the charging device to connect the to-be-charged object and the trickle charging circuit, and the condition of the switching device is monitored, and trickle charging is continued for a predetermined time according to the to-be-charged object. And a timer for switching the connection between the object to be charged and the trickle charging circuit to the connection between the object to be charged and the quick charging circuit when the switching signal is sent to the switching device. Equation charge control device.