JPH10326630A - Secondary battery control circuit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To allow the electric energy charged in secondary batteries to all be used by the load without being disposed of by a discharger etc., which should be achieved without generating a memory effect in the secondary batteries installed in the apparatus concerned. SOLUTION: Two sets of secondary batteries 5 and 6 are installed in an apparatus, and one of them is connected to the load by an interlocking switch 1 while the other is connected to a charger. The battery connected to the load is monitored, and when the proper discharge end voltage is attained, the battery connected to the load and the one connected to the charger are changed over by the switch 1 simultaneously so that use and charging of the batteries are conducted alternately.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention monitors a secondary battery connected to a load, uses the secondary battery connected to a load and a secondary battery connected to a charger at the same time after using the battery to an appropriate discharge end voltage. The electric energy charged in the secondary battery can be used at the load by switching and using it without causing a memory effect on the secondary battery and without disposing a part of the electric energy charged in the secondary battery by a discharger or the like. All of them can be used.

[0002]

2. Description of the Related Art Some secondary batteries, such as nickel-cadmium batteries and nickel-metal hydride batteries, have a memory effect depending on how they are charged and discharged. Secondary batteries have been discarded due to the memory effect, and devices incorporating the secondary batteries have been discarded. Conventionally, measures to prevent the memory effect have been taken, such as disconnecting the secondary battery from the load, discharging the battery with a discharger, and then charging the battery.

[0003]

In order to prevent the device from becoming unusable for a certain period of time, the user is unaware that a memory effect occurs in the secondary battery without taking any precautionary measures, Problems such as being unusable for a certain period of time, requiring manual work such as attaching and detaching a secondary battery from the device, and disposing of a part of the charged electric energy in a discharger without using it Had a point.

[0004]

The memory effect occurs in the secondary battery because the charging / discharging is repeated repeatedly. After the secondary battery is used up to an appropriate discharge end voltage at which the memory effect does not occur, the secondary battery is charged. If the memory effect does not occur, monitor the secondary battery connected to the load, use it to the appropriate discharge end voltage, and then switch simultaneously between the secondary battery connected to the load and the secondary battery connected to the charger Use and charge alternately.

[0005]

By doing so, the secondary battery connected to the charger is charged while using the secondary battery connected to the load,
The secondary battery connected to the load can be used up to the proper discharge end voltage without being charged on the way, and is not charged until switching. When the secondary battery connected to the load and the secondary battery connected to the charger are switched,
The charged secondary battery is connected to the load, while the used secondary battery is charged up to a proper discharge end voltage at which no memory effect occurs. Therefore, the electric energy charged in the secondary battery can be used entirely by the load without being discarded by the discharger or the like, and the memory effect does not occur.

[0006]

FIG. 1 is a block diagram showing an embodiment of the present invention.
Two sets of secondary batteries 5 and 6 are connected to the interlock switch 1, and when one secondary battery is connected to a load, the other secondary battery is connected to a charger. When the interlock switch 1 is switched, the secondary battery connected to the load is connected to the charger, and at the same time, the secondary battery connected to the charger is connected to the load. In this way, the secondary battery connected to the charger is charged while the secondary battery connected to the load is being used, and the secondary battery connected to the load is not charged until the interlock switch 1 is switched. Interlock switch 1
By monitoring the voltage at point a to which the load is connected, the voltage of the secondary battery that is always connected to the load is monitored regardless of which of the secondary batteries 5 and 6 is connected to the load. can do. The discharge voltage monitoring circuit 2 detects that the secondary battery connected to the load has been used up to the proper discharge end voltage at which the memory effect does not occur, and switches the interlock switch 1 accordingly. When the interlock switch 1 is switched, the secondary battery charged by the charger is connected to the load,
At the same time, the secondary battery used up to the proper discharge end voltage at the load is connected to the charger. The charging voltage monitoring circuit 3 is a circuit that monitors whether the secondary battery connected to the charger has been charged. When the secondary battery connected to the charger has not been charged, the charging voltage monitoring circuit 3 prevents the interlock switch 1 from being switched so that the uncharged secondary battery is not connected to the load. Is what you do. In the case where the secondary battery connected to the charger is completely charged while the secondary battery connected to the load is used up to the proper discharge end voltage, the charging voltage monitoring circuit 3 is not provided. Is also good. In the case of a device such as an electric razor or a flashlight that has information that can be sensed by the user during use, such as the motor sound and light intensity, as shown in FIG. It is conceivable that a person senses with eyes or ears and switches the interlocking switch without monitoring with an electronic circuit whether the battery has been used up to the discharge end voltage.

[0007]

Thus, no matter when the charger is started or stopped, the secondary battery connected to the load is not charged until the interlock switch 1 is switched. Then, even if the charging of the secondary battery during the charging operation is interrupted on the way, only the self-discharge occurs. Therefore, since the secondary battery does not repeat shallow charge and discharge, the memory effect does not occur in the secondary battery. In addition, since no discharger is used, the charged electric energy can be used at the entire load without discarding. In particular, even when the charging operation is repeatedly started and stopped for a long time in an unmanned device using a solar cell or the like, the secondary battery does not have a memory effect.

[Brief description of the drawings]

FIG. 1 is a block diagram of an embodiment of the present invention.

FIG. 2 is a block diagram when a human performs a switch operation.

FIG. 3 is a circuit diagram of an example of an embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Interlock switch 2 Discharge voltage monitor circuit 3 Charge voltage monitor circuit 4 Switch control circuit 5 Secondary battery 6 Secondary battery 7 Load 8 Charger 9 Comparator 10 Latching relay

Claims (1)

[Claims] The present invention relates to a secondary battery, wherein a secondary battery connected to a load and a secondary battery connected to a charger are simultaneously switched after a secondary battery is monitored electronically or manually and used up to an appropriate discharge end voltage. A circuit that alternates between using and charging.