JP3197618B2 - Charger - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a battery charger for charging a battery while detecting the temperature of the battery.

[0002]

2. Description of the Related Art In a charger for charging a secondary battery such as a nickel cadmium battery (Ni-Cd battery) or a nickel hydride battery (Ni-MH battery), a method for detecting the full charge of a battery is as follows. There are a peak sensor system that detects the peak voltage of the battery, and a -ΔV sensor system that detects that the charged battery voltage slightly drops from the peak value.

Further, in a battery which is sensitive to temperature such as a Ni-MH battery, charging under a high or low temperature condition reduces the cycle life of the battery. Therefore, Japanese Patent Application Laid-Open No. 1-192323 discloses a temperature protection function that detects the temperature of a battery, suspends charging when the battery temperature reaches a charging suspension temperature, and resumes charging when the battery temperature returns to a charging return temperature. It has.

[0004]

As described above, by suspending and resuming charging depending on the battery temperature, the cycle life of the battery is not reduced. As long as the temperature does not return to the normal temperature, the charging pause state is continued and the charging is not completed. In addition, when the battery temperature is changed to the trickle charge instead of the complete charge pause when the battery temperature becomes the charge pause temperature, the trickle charge does not end indefinitely, and the battery is deteriorated. I will.

[0005] It is an object of the present invention to prevent the charging pause state or the trickle charging state from continuing forever, preventing the charging from being terminated and causing the battery to deteriorate.

[0006]

SUMMARY OF THE INVENTION A first charger according to the present invention detects the temperature of a battery to be charged, suspends rapid charging when the battery temperature reaches a charging suspension temperature, and returns the battery temperature to a charging return temperature. Then, temperature detection charging means for resuming rapid charging, trickle charging means for trickle charging the battery when the battery temperature becomes the charging suspension temperature and the rapid charging is suspended,
Starts counting from the time the battery temperature has suspended the rapid charging becomes charging suspension temperature, the rapid charging has elapsed at <br/> constant time without being restarted timing means for emitting trickle charge end signal, the ends Finished trickle charge based on signal
And display means for displaying abnormal termination .

Further, the second charger of the present invention detects the temperature of the battery to be charged, suspends charging when the battery temperature reaches the charging suspension temperature, and resumes charging when the battery temperature returns to the charging return temperature. a temperature detecting charging unit, starts counting from when the battery temperature has suspended the charge becomes the charging suspension temperature, charge and
Charge termination signal and collector has passed a predetermined time without being restarted
Timing means for emitting items, a charge based on said termination signal
Display means for displaying an abnormal end when the process is completed .

[0008]

According to the charger of the present invention, when the battery temperature becomes the charging suspension temperature and the trickle charging is started or the charging is paused, the timing means starts time counting, and when a predetermined time elapses, the trickle charging is started. Alternatively, the charging suspension is forcibly terminated and an abnormal termination is displayed.

[0009]

FIG. 1 is a block circuit diagram showing an embodiment of the present invention. The charging power supply 1 is a constant voltage, constant current or constant voltage / constant power supply, and charges the battery B. The temperature detecting and charging means 2 includes a thermistor 3 for detecting the temperature of the battery B,
A temperature detection circuit 4 that processes the output signal of the thermistor 3 to determine whether the temperature of the battery B has reached the charging pause temperature or the charging return temperature, and is connected between the charging power supply 1 and the battery B. And a quick charge switch 7 to which an output signal of the temperature detecting circuit 4 is inputted through two OR gates 5 and 6 connected in series.

The temperature detection circuit 4 determines that the temperature T of the battery B is the charging suspension temperature, that is, TL2> T, T> TH1 (for example, TL
2 = −3 ° C., TH1 = 60 ° C.), the rapid charging is stopped, and the battery temperature T becomes the charge return temperature, that is, TL1 <T <T.
When H2 (for example, TL1 = 0.degree. C., TH2 = 45.degree. C.), a signal for restarting rapid charging is output. The quick charge switch 7 is turned on / off in response to such a signal.

In this embodiment, a slight difference is provided between the charging pause temperature and the charging return temperature. However, such a difference is not always necessary and may be the same. The trickle charging means 8 includes a trickle timer 9 for setting a trickle charging period, a trickle charge switch 10 connected between the charging power supply 1 and the battery B, and an output signal of the trickle timer 9 being input, and a trickle charge switch. And a current limiting resistor 11 for adjusting the charging current applied to the battery B.

The trickle timer 9 starts counting in response to the output of the OR gate 5, and when a predetermined time, for example, eight hours, is counted, the trickle charge switch 10 is turned off. ΔV sensor 12 detects the voltage of battery B,
When the current voltage Vn falls below the maximum voltage after the start of charging, that is, the peak voltage Vmax by ΔV, a signal to stop rapid charging is output to the OR gate 5.

FIG. 2 is a flowchart showing the operation of the charger in the present embodiment. First, when charging starts,
The trickle charge switch 10 is turned on to start trickle charging of the battery B (step S1). Temperature detection circuit 4
Is based on a signal from the thermistor 3, the temperature T of the battery B is higher than TL1 (for example, 0 ° C.) and TH1 (for example,
0 ° C.) (Step S2)
If it is larger than TL1 and smaller than TH1, the quick charge switch 7 is turned on to start the quick charge of the battery B (step S3).

The ΔV sensor 12 detects the voltage Vn of the battery B, and determines whether or not the voltage V has dropped from the peak voltage Vmax by ΔV (step S4). When it is determined that the voltage has decreased by ΔV, the quick charge switch 7 is turned off to stop the quick charge (step S5), and thereafter, the trickle timer 9 is set (step S6), and the trickle charge is performed for a predetermined time. After a certain time has elapsed (step S7),
Turn off the trickle charge switch 10 (step S
8) Terminate the charging.

In step 4, the voltage of battery B, ΔV
If the decrease is not determined, it is detected whether the temperature T of the battery B has become lower than TL2 (for example, −3 ° C.) or higher than TH1 (step S9). When the temperature T of the battery B becomes lower than TL2 or higher than TH1, the quick charge switch 7 is turned off to suspend the quick charge (step S10), and the trickle timer 9 is set (step 11). Charge the battery.

After the trickle timer 9 is set, the set time of the trickle timer 9 is completed (step S13) without the temperature T of the battery B not exceeding TL1 or TH2 (for example, 45 ° C.) (step S12). Then, an abnormal termination display is performed (step S14), the trickle charge switch 10 is turned off (step S8), and the charging is forcibly terminated.

In step S12, before the set time of the trickle timer 9 is completed, the temperature of the battery B becomes TL1.
When it is detected that the above-mentioned value has become equal to or less than TH2, the quick charge switch 7 is turned on to restart the quick charge (step S3), and the subsequent processing is performed. By the way, when it is determined in step S2 that the temperature T of the battery B is equal to or lower than TL1 or equal to or higher than TH1 (ie,
Immediately after the trickle charge is started in step 1, if the temperature of the battery B is already equal to or lower than TL1 or equal to or higher than TH1, the trickle timer 9 is immediately set (step 11), and the processing from step 12 onward is performed. I do.

In the above-described embodiment, the trickle charging means 8 performs trickle charging during the pause of the rapid charging. However, such trickle charging is not always necessary, and even if the charging is completely stopped. Good.

[0019]

According to the battery charger of the present invention, when the battery temperature becomes the charging pause temperature and trickle charging is started,
If has time counting means from the time of pause charging starts clocking for a predetermined time elapses, the forcibly terminates the trickle charging or charging suspension, so to display the abnormal termination, the charge
Pause or trickle charge continues forever
Not complete, or cause battery deterioration
Can be prevented, and be aware of the charger user
Can be aroused.

[Brief description of the drawings]

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

FIG. 2 is a flowchart showing a charging operation according to one embodiment of the present invention.

[Explanation of symbols]

 2 Temperature detection charging means 8 Trickle charging means 9 Trickle timer B Battery

Continuation of the front page (56) References JP-A-64-19923 (JP, A) JP-A-5-328629 (JP, A) JP-A-5-168170 (JP, A) JP-A 64-19923 (JP) JP-A-61-191237 (JP, A) JP-A-5-38069 (JP, A) JP-A-64-64532 (JP, A) JP-A-3-7025 (JP, A) 63-24942 (JP, U) (58) Field surveyed (Int. Cl. ⁷ , DB name) H02J ^7/ 00-7/35 H04M 10/44

Claims (2)

(57) [Claims] A temperature detecting and charging means for detecting a temperature of a battery to be charged, suspending rapid charging when the battery temperature reaches a charging suspension temperature, and resuming rapid charging when the battery temperature returns to a charging return temperature; A trickle charging means for trickle-charging the battery when the battery temperature becomes the charging suspension temperature and the rapid charging is suspended, and time measurement is started when the battery temperature becomes the charging suspension temperature and the rapid charging is suspended, and the rapid charging is resumed. This
A trickle charge end signal is issued when a predetermined time elapses
A trickle charge based on the end signal.
Display means for displaying an abnormal end when the charging is completed. 2. A temperature detecting and charging means for detecting a temperature of a battery to be charged, suspending charging when the battery temperature reaches a charging suspension temperature, and resuming charging when the battery temperature returns to a charging return temperature; Timer means for starting time measurement from the time when the charging is stopped due to the quiescent temperature and issuing a charge end signal when a predetermined time elapses without charging being restarted;
When charging is terminated based on the end signal, abnormal termination is displayed.
And a display means for displaying the information .