JP2002112467A - Battery charger - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a battery charger which timely prompts the user to charge the battery. SOLUTION: The charger determines whether the battery life is being shortened or not (S112) referring to the past charging history stored in a EEPROM 54. If it decides that the battery life is being shortened (112: Yes), it outputs a voice alarm 'Overcharging' for appropriate charging (S114). Thus, when the user repeats charging in a way to reduce the battery life, it advices the user to make appropriate charging.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a charging device for calling attention by voice when charging is not performed properly based on a charging history.

[0002]

2. Description of the Related Art At present, a battery pack containing a rechargeable battery which can be repeatedly used as a power source of a power tool or the like is used. The charging device performs charging with, for example, a constant current when the battery pack is loaded, and stops charging when detecting full charge based on a battery voltage change pattern or the like.

[0003]

However, when the above-described charging device is handled out of the original usage, the battery life is extremely shortened. For example, if the user plugs in the charger with little use of the battery and recharges the battery that has consumed little capacity,
Gas is generated inside the battery just before full charge and the pressure is increased.Because the gas is generated again before the gas is absorbed and the internal pressure is further increased, the electrode is damaged and the life is shortened. Become. In addition, if the battery is charged after being used to the overdischarged state, the life of the battery is shortened. Further, when charging is started in an extremely low temperature state such as outdoors in a cold winter area, or conversely, in a high temperature state immediately after the capacity is used up by a high-load power tool, the life is extremely shortened.

In addition, the conventional charging device has a problem that it is not possible to know how many times the battery can be charged later.

[0005] The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a charging device that can prompt a user to perform proper charging.

It is another object of the present invention to provide a charging device capable of notifying the number of times that charging is possible.

[0007]

According to a first aspect of the present invention, there is provided a charging apparatus for charging a battery pack having a storage device for storing a charging history, wherein the charging history is stored in the storage device. Recording means for recording; determining means for determining whether or not past charging stored in the storage device shortens battery life; and charging history is poor when the determining means determines that the life is shortened. And a sound output device that outputs the sound as a technical feature.

According to the first aspect, it is determined whether or not the past charging stored in the storage device shortens the battery life, and when it is determined that the life is shortened, a sound is output so as to perform appropriate charging. . For this reason, when the user repeats charging that shortens the battery life, the user can be alerted and can perform proper charging.

According to another aspect of the present invention, there is provided a charging device for charging a battery pack having a storage device for storing a charging history, wherein the recording device records the charging history in the storage device. A technical feature comprising: a life estimation unit for estimating a possible number of times of charging from a history stored in the storage device; and a sound output device for outputting a voice of the number of times of charging estimated by the life estimation unit. I do.

According to a second aspect of the present invention, the number of possible chargings is estimated from the history stored in the storage device, and is output as a voice. For this reason, the user can be notified of the number of times that charging is possible.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a charging device according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows a charging device 10 and a battery pack 50 according to the first embodiment of the present invention.
Is shown. In the battery pack 50, an EEPROM that stores a charging history together with the nickel hydrogen battery B is provided.
54 and a temperature sensor (thermistor) 56 are housed.

On the other hand, the control circuit 30 of the charging device 10 includes a temperature detector 38 for detecting a battery temperature based on an output value from the temperature sensor 56, a storage unit 39 for storing control information, and an EEPROM 54 for the battery pack 50. The charging history is read out, it is determined whether or not proper charging is being performed, and the battery life is estimated. Further, the charging current is determined based on the battery temperature detected by the temperature detecting unit 38, and the charging current is controlled as a current command value. A control unit 36 for outputting to the unit 34;
A charging current control unit 34 for controlling the power supply circuit 32 based on the current command value from 6 to adjust the charging current of the battery;
A power supply circuit 32 that performs charging by applying a voltage to the battery pack 50, an audio output switch 40 that outputs audio whether proper charging is being performed, and an audio playback unit that outputs audio from the speaker 44. 42.

In the charging device 10 of this embodiment, when the audio output switch 40 is operated, the EE on the battery pack 50 side is operated.
Based on the charging history stored in the PROM 54, it is determined whether or not proper charging is being performed. When proper charging is being performed, a sound saying "charging friendly to the battery" is output from the speaker 44. At the same time, the number of remaining chargeable times is estimated based on the charge history, and for example, a voice saying “the remaining 300 can be used” is output from the speaker 44.

On the other hand, when the battery pack is used again to shorten its life, specifically, when charging is repeated again in a state where the battery pack consumes only a small amount of capacity, the voice is output as "overcharging tendency". On the other hand, if the battery is frequently charged in a state where the voltage is extremely low due to overdischarge or long-term storage, a sound is output as "overdischarge tendency". On the other hand, when charging is frequently started at a high temperature, for example, when used in a power tool and charging is started in a state where heat is generated by discharging, or when charging in a place where sunlight is received in summertime , "Tends to be hot." Conversely, when charging is frequently started at a low temperature, for example, when the battery is frequently charged outdoors in winter, the voice is output as "low temperature tendency". As a result, the user is alerted and proper charging is performed, thereby extending the battery life.

The charging operation of the charging device 10 will be described more specifically with reference to the flowchart of FIG. When the control unit 39 of the control circuit 30 detects that the battery pack 50 is filled via a voltage detection unit (not shown) (S12: Yes), the control unit 39 reads the charging history data stored in the EEPROM 54 (S14). The charging history data includes a number of times of charging, and a 4-bit history flag indicating a temperature discrimination and a capacity classification when charging for the past four times is started. As shown in FIG. 4, in the history flag, the first bit is a high-temperature bit indicating that the temperature was high (more than 30 ° C.) at the start of charging, and the second bit was a low temperature (10 ° C. or less) at the start of charging. The third bit is an overcharge bit indicating that the battery has a high capacity (capacity 70% or more) at the start of charging, and the fourth bit is a low capacity bit (capacity) at the start of charging. 0% or less).

In FIG. 4, a history flag in the previous charging is shown.
1000 ”indicates that charging was started at a high temperature, and 2
The history flag “0101” in the previous charging indicates that charging was started at a low temperature and in an overdischarged state.

Subsequently, the control unit 39 controls the battery pack 50
Is detected via the temperature detector 38 based on the output value from the temperature sensor 56 (S16), and the capacity of the battery pack is detected based on the open voltage before the start of charging (S18). Thereafter, the history flag five times before is reset (S22), and the current history is left (S30 to S46). That is, since the charging device of the present embodiment holds the past four charging histories,
The previous charge history data is replaced with the current data.

First, it is determined whether the temperature is high (above 30 ° C.) (S30). Here, when the temperature is high (S30: Y
es), the first bit (high temperature bit) of the history flag is set to 1 (S32). When the temperature is not high (S30: N
o) Then, it is determined whether the temperature is low (10 ° C. or less) (S)
34). Here, when the temperature is low (S34: Ye
s), the second bit (low temperature bit) of the history flag is set to 1 (S34). If neither high nor low (S
34: No), the flow shifts to S40 without setting the flag.

Next, it is determined whether the capacity is high (70% or more) (S40). Here, when the capacity is high (S4
0: Yes), the third bit (overcharge bit) of the history flag is set to 1 (S42). If the capacity is not high (S40: No), it is determined whether the capacity is low (0% or less) (S44). Here, when the capacity is low (S4
4: Yes), the fourth bit (overdischarge bit) of the history flag is set to 1 (S34). If the capacity is neither high nor low (S44: No), the process proceeds to S50 without setting a flag.

In S50, it is determined whether any bit has been set to 1, that is, whether the current charge is appropriate. Here, when the charging is appropriate (S50: Y
es), the number of times of charging is increased by one (S54). On the other hand, if the charging is not appropriate (S50: No), the charging frequency is set to 3
Increase the number of times (S52). That is, improper charging corresponds to repeating appropriate charging three times, and is stored as being charged three times. Thereafter, charging is started (S5).
6) Charging is performed while adjusting the charging current based on the battery temperature. If the above-described voice output switch 40 is operated during charging (S58: Yes), the process proceeds to S100, and voice output processing for outputting voice as to whether charging is being performed properly and the remaining number of uses of the battery is performed. Is performed (S100). Then, when the charging is completed (S60: Yes), the process is terminated.

The sound output processing in S100 will be described with reference to FIG. 3 showing a subroutine of the processing. First, the control unit 36 calculates the average of the past four charging times and the current charging history from the history flag described above with reference to FIG. 4 (S
102). For example, if charging at a high temperature has been started three times in the past, the average is 0.6. If charging has been started once at a low temperature in the past, the average is 0.2. In this case, the average becomes 0, and if the start of overdischarge has been performed twice in the past, the average becomes 0.4.

Subsequently, it is determined whether or not there is a tendency to start charging at a high temperature from the average value of charging at a high temperature (S10).
4). Here, if the average value is 0.4 or more, it is determined that there is a tendency for high temperature (S104: Yes), and the sound (1: high temperature tendency) is output from the speaker 44 via the sound reproduction unit 42 (S106). On the other hand, when there is no high temperature tendency (S104: No), the process proceeds to S108.

Then, it is determined whether or not there is a tendency to start charging at a low temperature from the average value of starting charging at a low temperature (S10).
8). Here, when the average value is 0.4 or more, it is determined that there is a low-temperature tendency (S108: Yes), and a sound (2: low-temperature tendency) is output from the speaker 44 (S110). On the other hand, when there is no low temperature tendency (S108: No), S1
Proceed to 12.

Subsequently, it is determined whether or not there is a tendency to start charging at a high capacity based on the average value at the start of charging at a high capacity (S).
112). Here, when the average value is 0.4 or more, it is determined that there is an overcharge tendency (S112: Yes), and the sound (3:
Overcharging tendency) through the speaker 4
4 (S114). On the other hand, when there is no high capacity tendency (S112: No), the process proceeds to S116.

Then, it is determined whether charging tends to be started at a low capacity based on the average value at the start of charging at a low capacity (S1).
16). Here, when the average value is 0.4 or more, it is determined that there is an overdischarge tendency (S116: Yes), and a sound (4: overdischarge tendency) is output from the speaker 44 (S11).
8). On the other hand, when there is no tendency to overdischarge (S116: N
o), and proceed to S120.

Finally, it is determined whether appropriate charging has been performed, that is, whether the average value of the high-temperature bit, low-temperature bit, overcharge bit, and overdischarge bit of the history flag is all less than 0.4 (S120). . Here, when appropriate charging is being performed, that is, when the above-mentioned S106, S110, S114, S
If the audio output at 118 is not performed (S12
0: Yes), sound (5: battery-friendly charging) is output from the speaker 44 (S122).

Thereafter, the remaining chargeable number is estimated by subtracting the charge number accumulated in S52 or S54 from the preset standard charge number (S12).
4), the estimated number of chargeable times is voiced from the speaker 44,
For example, it outputs "can be used 300 times".

In the present embodiment, a 4-bit flag is used to leave four items of high temperature, low temperature, low capacity, and high capacity as histories. However, a high frequency and a low temperature occur less frequently in a series of histories, and a low frequency and a high capacity occur less frequently in a series of histories. For this reason, by setting one bit when charging is started at high or low temperature, and setting one bit when starting charging at low or high capacity, the flag has a two-bit configuration, and It is also possible to reduce the capacity.

[0029]

According to the present invention, it is determined whether or not the stored past charging history shortens the battery life, and when it is determined that the life is shortened, a sound is output so as to perform appropriate charging. For this reason, when the user repeats charging that shortens the battery life, the user can be alerted and can perform proper charging. In addition, the number of possible charging times is estimated from the stored history, and output by voice. For this reason, the user can be notified of the number of times that charging is possible.

[Brief description of the drawings]

FIG. 1 is a block diagram of a charging device and a battery pack according to a first embodiment of the present invention.

FIG. 2 is a flowchart illustrating main processing by a control circuit according to the first embodiment.

FIG. 3 is a flowchart showing a subroutine of a sound output process in FIG. 2;

FIG. 4 is an explanatory diagram of a charging history of the charging device according to the first embodiment.

[Explanation of symbols]

 REFERENCE SIGNS LIST 10 charging device 30 control circuit 32 power supply circuit 33 voltage measurement unit 34 charging current control unit 36 control unit (judgment unit, life estimation unit) 38 temperature detection unit 39 storage unit 39B EEPROM (storage device) 40 audio output switch 42 audio reproduction unit (Audio output device) 44 Speaker 50 Battery pack 54 EEPROM (Recording device)

Claims (2)

[Claims] 1. A charging device for charging a battery pack having a storage device for storing a charging history, comprising: a recording unit for recording a charging history in the storage device; and a battery for storing past charging stored in the storage device. Judging means for judging whether to shorten the life, and when it is judged by the judging means to shorten the life,
And a voice output device that outputs a voice indicating that the charging history is poor. 2. A charging device for charging a battery pack having a storage device for storing a charging history, comprising: a recording unit for recording a charging history in the storage device; and a history stored in the storage device. A charging device comprising: a life estimation unit for estimating the number of times of charging; and a voice output device for outputting a voice of the number of times of charging estimated by the life estimation unit.