JPH0426333A - Charger - Google Patents

Abstract

PURPOSE:To lengthen the cycle life of a secondary battery and to perform charging operation with high time efficiency by reading out the number of time of charging operation of a battery through a memory means and making a judgment whether the battery is fully discharged based on thus read out number of charging time and then charging the battery. CONSTITUTION:Upon mounting of a battery 10, a charge/discharge control section 44 reads out ID of the battery 10 through a bar code detecting section 42 while furthermore reads out the number of time of charging operation from a charging history memory section 43 and then makes a judgment whether the number of time of charging operation is a multiple of 10, for example. When it is a multiple of 10, a judgment is made whether the battery 10 is overcharged. If it is not a multiple of 10, an SW circuit 23 is turned ON to charge the battery 10 quickly through a -DELTAV detection control circuit 20. Consequently, battery trouble is prevented and the cycle life of the secondary battery is lengthened while furthermore the battery can be charged in a short time as compared with the conventional way.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a charging device for charging a secondary battery such as a Ni--Cd battery.

〔overview〕

The present invention stores the number of times the battery has been charged, determines whether the battery is sufficiently discharged or not based on the number of times the battery has been charged, and charges the battery only when the discharge is sufficient. This is designed to extend the cycle life of the battery.

[Prior Art] Conventional charging devices charge the secondary battery by detecting -ΔV of the secondary battery, detecting the temperature of the secondary battery, and managing time using a timer. ing.

These conventional charging devices, when a secondary battery is installed,
Charging has started regardless of the remaining capacity of the secondary battery. However, if a secondary battery that has not been sufficiently discharged is repeatedly charged, the internal circuit may short out due to deterioration of the secondary battery's seven-stage regulator, and the cycle life of the secondary battery may be shortened due to activation. Furthermore, there is a problem in that the amount of melt in the secondary battery cannot be extracted as specified due to the memory effect.

Therefore, in order to prevent the above-mentioned troubles, charging devices with a discharger having a battery discharging function are commercially available.

[Problem to be solved by the invention]

However, since the charging device with a discharger starts charging after discharging the battery each time, the charging time is long and it is not practical.

This is due to the fact that the battery is unconditionally discharged without detecting its remaining capacity.

Therefore, instead of discharging unconditionally, you can extend the cycle life of the secondary battery by discharging only when necessary based on judgment based on the discharge state and then charging. It is also thought that time-efficient charging can be achieved.

An object of the present invention is to enable charging after discharging only when necessary.

(Means for solving problems) The means of the present invention are as follows.

Charging equipment (refer to the functional block diagram in Figure 1, the same applies hereinafter)
is a means of charging the battery.

The discharging means 2 is means for discharging the battery.

Further, the storage means 3 is a means for storing the number of times the battery has been charged.

Furthermore, when the battery is installed, the control means 4 determines whether the battery is sufficiently or insufficiently discharged based on the number of times the battery has been charged stored in the storage means 3, and the control means 4 determines whether the battery is sufficiently discharged or not. means for controlling the charging means 1 to charge the battery if sufficient, and for controlling the charging means 2 to charge the battery after the discharging means 2 has discharged the battery if insufficient; be. In addition to the number of times of charging, the cumulative charging time may also be taken into account for control.

[For production]

The operation of the means of the invention is as follows.

When a battery is attached, the control means 4 reads the number of times the attached battery has been charged from the storage means 3, and determines whether or not the battery has been sufficiently discharged based on the number of times the battery has been charged. If the battery is not sufficiently discharged, the battery is sufficiently discharged via the discharging means 2, and then the battery is charged via the charging means 1. On the other hand, if the battery is already sufficiently discharged, the battery is immediately charged via the charging means 1.

Therefore, charging can be performed after discharging only when necessary.

〔Example〕

Examples will be described below with reference to FIGS. 2 to 5.

FIG. 2 is a block diagram showing the system configuration of the charging device of the first embodiment.

In the figure, this charging device includes a plurality of (N) batteries 1
A 1Δ■ detection control circuit 2o for rapidly charging the battery 0, and a discharger circuit for discharging the battery 10 that has few charge/discharge cycles, that is, is not sufficiently discharged. It has 30. Also, battery I
A bar code (not shown) for identification (ID) is attached to each O.

- The ΔV detection control circuit 20 includes a peak value storage unit 21 for storing the peak value of the voltage of the battery 10, a comparison circuit 22 that compares the peak value stored by the peak value storage unit 21 and the voltage of the battery 10, and constant current circuit 24 to battery 10
The charge output for! It has a switch (SW) circuit 23 for controlling the current on/off, and a constant current circuit 2.
4 rapidly charges the battery 10 via the SW circuit 23.

The discharger circuit 30 includes a discharge resistor 31 for discharging the battery 10 and an SW circuit 32 for controlling on/off the discharge tt current output from the battery 10 to the discharge resistor 31.

In this charging device, the -Δ■ detection control circuit 20 also
A quick charging time measurement unit 41 that measures the charging time from the start of quick charging to trickle charging (supplementary charging) to 0, and a quick charging time measuring unit 41 that measures the charging time until switching to trickle charging (supplementary charging), and a quick charging time measuring unit 41 for reading the bar code given to the battery 10 to identify the battery 10. It has a barcode detection section 42.

This charging device further includes a charging history storage section 4 that individually stores the number of past charging times and past cumulative charging time for each battery 10.
3 and each battery 10 stored by the charging history storage unit 43.
Based on the past number of charging times and cumulative charging time, battery 1
When the discharge amount of 0 is sufficient, the SW circuit 23 is turned on so that the 1 ΔV detection control circuit 20 can rapidly charge the battery 10, and when the discharge amount of the battery 10 is insufficient,
First, the discharger circuit 30 sufficiently discharges the battery 10, and then the -Δ■ detection control circuit 20 quickly charges the battery 10. It has a charge/discharge control section 44 that controls each of the SW circuits 23 .

When the battery 10 is charged, the charging/discharging control unit 44 increments the number of past charging times of the battery 10 stored by the charging history storage unit 43 by one, and further calculates the charging time and the cumulative charging time obtained by integrating the charging time. The barcode detecting section 42 detects the barcode given to the battery 10 and stores the information in the area corresponding to the battery 10 in the charging history storage section 43 based on the detected barcode. Make me remember.

Here, the determination as to whether the discharge amount of the battery 10 is sufficient or insufficient is based on the remaining capacity of the battery 10 when the battery-powered device to which the battery 10 supplies power has finished operating, This is done based on how the battery 10 is used (number of times of use, etc.), the target value of the cycle life of the battery 10, the characteristics of the battery 10, etc.

For example, when the battery 10 is used once, about 40% of the capacity of the battery 10 is discharged, and the remaining capacity at the end of discharge is 10%.
%, and if the battery 10 is used under the condition that 1% of the capacity of the battery 10 is charged in 1 minute, the battery 10
If the battery is discharged when its remaining capacity is 60-10%, it is likely to cause a memory effect phenomenon.

Therefore, when used under the above conditions, 5 to 1
By determining whether the discharge amount of the battery 10 is sufficient every time the battery 10 is charged, it is possible to prevent the memory effect phenomenon of the battery 10 from occurring.

FIG. 3 is a flowchart for explaining the operation of the charging device shown in FIG. 2, particularly the operation of the charge/discharge control section 44.

When the battery 10 is installed, the charge/discharge control unit 44 first reads the ID of the battery 10 via the barcode detection unit 42 (
Step 551), then the number of charging times corresponding to this ID is read from the charging history storage unit 43, and it is determined whether or not this number of charging times is a multiple of, for example, 10 times (step 552).

If the number of discharges of the battery 10 is a multiple of 10, the process advances to step S53, where the past cumulative charging time corresponding to the ID is read from the charging history storage unit 43, and the battery 10 is determined to be in an overcharged state. In other words, it is determined whether the discharge amount of the battery 10 is sufficient. In this step S53, it is determined that the discharge amount of the battery 10 is sufficient when the cumulative charging time is, for example, 90 minutes x 10 times or more,
For example, if it is less than 40 minutes x 10 times, it is determined that the battery 10 is in an overcharged state, that is, the amount of discharge of the battery 10 is insufficient. If the battery is overcharged, the process advances to step 54.

In step S54, the SW circuit 32 of the discharger circuit 30 is turned on to discharge the battery 10 via the discharger circuit 30 until the remaining capacity of the battery 10 becomes approximately 10%.

On the other hand, in step S552, if the number of times the battery 10 has been charged is not a multiple of 10, or in step S53
In this case, if the cumulative charging time is, for example, 40 minutes x 10 times or more, or if the discharging is completed in step S54, the process proceeds to step S55, the SW circuit 23 is turned on, and the -Δ■ detection control circuit 20 is turned on. to rapidly charge the battery 10.

Therefore, according to the first embodiment, a plurality of batteries 10
Since a bar code is assigned to each battery and it is determined whether the discharge amount is sufficient or insufficient for each battery 10, it is suitable when one charging device is used by many users. .

Next, FIG. 4 is a block diagram showing the system configuration of the second embodiment, and the same parts as in the above-described first embodiment are given the same reference numerals.

In the second embodiment, the barcode detection unit 42 in the first embodiment is omitted, and the charging history storage unit 43a stores the past number of charging times and cumulative charging time of only one battery 10. ing.

Therefore, in the operation of the charge/discharge control section 44a, the ID
Step 551 (FIG. 3) of performing detection is unnecessary. This second embodiment is suitable when one charging device is used by one user, and can be manufactured at a lower cost than the first embodiment.

Next, FIG. 5 is a system configuration diagram of a third embodiment, and in this example, the quick charging time measuring section 41 and charging history storage section 43a in the second embodiment are omitted.
The charge/discharge control unit 44b counts the number of times the battery 10 has been charged, and when the number of times the battery 10 has been charged reaches a specific number (for example, 10 times), the battery 10 is discharged and then charged. Can prevent charging. Further, since the charging/discharging time measuring section 41 and the charging history storage section 43a are not required, the second embodiment can be manufactured at a lower cost than the second embodiment.

Furthermore, the discharger circuit 30 is omitted, and whether the discharge amount is sufficient or insufficient is determined based on the number of charging times, etc.
If the user is warned using an LED or the like, it can be manufactured at lower cost.

〔Effect of the invention〕

According to the present invention, it is determined whether the battery is sufficiently or insufficiently discharged based on the number of times the battery has been charged or the cumulative charging time, etc., and if the battery has been sufficiently discharged, the battery is immediately charged; If the battery is insufficiently discharged, the battery is discharged and then charged, which prevents battery failure and extends the cycle life of the secondary battery. It can be charged in a shorter time.

[Brief explanation of drawings]

FIG. 1 is a functional block diagram of the present invention, FIG. 2 is a block diagram showing the system configuration of the charging device of the first embodiment, and FIG. 3 is a flowchart for explaining the operation of the charging device of the first embodiment. FIG. 4 is a block diagram showing the system configuration of the charging device according to the second embodiment, and FIG. 5 is a block diagram showing the system configuration of the charging device according to the third embodiment. DESCRIPTION OF SYMBOLS 1... Charging means, 2... Discharging means, 3... Storage means, 4... Control means.

Claims (1)

[Claims] 1) Charging means for charging the battery, discharging means for discharging the battery, storage means for storing the number of times the battery has been charged, and information stored in the storage means when the battery is attached. It is determined whether the battery is sufficiently or insufficiently discharged based on the number of times the battery has been charged, and if the battery is sufficiently discharged, the charging means charges the battery; and control means for controlling the charging means to charge the battery after the discharging means discharges the battery. 2) The storage means stores the number of times one battery has been charged and the cumulative charging time, and the control means controls charging and discharging of each battery based on the number of times the battery has been charged and the cumulative charging time stored by the storage means. The charging device according to claim 1, characterized in that: 3) The storage means stores the number of times each battery has been charged and the cumulative charging time, and the control means controls the charging and discharging of each battery based on the number of times each battery has been charged and the cumulative charging time stored by the storage means. The charging device according to claim 1, wherein the charging device controls: