JPH11233163A - Battery pack - Google Patents

Abstract

PROBLEM TO BE SOLVED: To correctly alarm and display the charging time of a battery without being affected by the lighting condition of an LED when the remaining capacity of the battery is displayed with a plurality of LEDs, and to charge the battery in the correct time based on the display to sufficiently develop the performance of a battery pack. SOLUTION: A battery pack 1 has one or more secondary batteries, a plurality of LEDs 7, and a circuit board, and the remaining capacity of the battery is processed with a control circuit 3 on the circuit board, the remaining capacity of the battery is displayed in proportion to the lighting number of the LEDs 7, and when battery voltage dropped to the discharge end voltage value previously set, requirement for charging is alarmed and displayed with the LEDs 7. The setting value of the discharge end voltage is varied according to the lighting number of the LEDs 7 with the control circuit 3 on the circuit board.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a notebook computer,
The present invention relates to a battery pack used for a mobile phone, a power tool, a power assisted bicycle, and the like, and particularly to a battery pack such as a power assisted bicycle that supplies a large load current and supplies power corresponding to a load having a large current fluctuation.

[0002]

2. Description of the Related Art As shown in the block diagram of FIG. 2, a conventional battery pack 8 generally indicates the remaining battery capacity by the number of lighted LEDs.

FIG. 2 shows a battery block 2 in which a plurality of nickel-hydrogen storage batteries are connected in series, five LEDs 7 for displaying the remaining capacity of the battery block 2, calculation of the remaining capacity of the battery block 2, a charge warning, and the like. FIG. 2 is a block diagram showing a control circuit 3 composed of an IC and a device main body 4 on a circuit board for performing the above.

[0004] The battery pack 8 and the main body 4 are connected with a + terminal on the side of the battery pack 8 and a + terminal on the side of the main body 4, and similarly, a − terminal on the side of the battery pack 8 and a − terminal on the side of the main body 4 are connected by a connector or the like. Electrically connected.

Next, the operation of each circuit in FIG. 2 will be described below.

[0006] The current from the battery block 2 flows through the load 5 and returns to the battery block 2 through the current detection resistor Ra. The voltage from the battery block 2 is
Is supplied as a power supply voltage to the control circuit 3 and the LED 7 through a smoothing circuit composed of a resistor Rb and a capacitor C for removing noise of the above, and a regulator circuit 6 for maintaining a constant voltage. The control circuit 3 operates by the supplied voltage, and the LED 7 is turned on.

The voltage of the battery block 2 is divided by two resistors Rc and Rd so that the voltage can be input to the control circuit 3 and is converted to a voltage level that can be input to the control circuit 3. The divided voltage is converted into digital data by the AD converter 31 and input to the voltage comparator 32. Voltage setting circuit 33b
Stores a preset discharge end voltage value of the battery. The voltage comparator 32 compares the battery voltage with the discharge end voltage. If the battery voltage becomes lower than the discharge end voltage, a charge request warning signal is issued. Is sent to the LED controller 34b. Upon receiving the charge request warning signal, the LED controller 34b blinks the LED 7 to notify the user of the charging time.

[0008] The voltage generated at the current detection resistor Ra is A-D
The data is converted into digital data by the converter 37 and sent to the remaining capacity calculator 38, where the current integration calculation process is performed, and the remaining capacity of the battery is calculated. The remaining capacity of this battery is LED
It is sent to the controller 34b. The LED controller 34b controls the LED 7 in proportion to the remaining capacity of the battery.
Is determined, and a signal is sent to the LED 7. Receiving this signal, the LED 7 displays the remaining capacity of the battery by the number of lighting of the LED 7.

[0009]

As described above, the resistance Rb
The smoothing circuit composed of the capacitor C and the capacitor C has an operation of removing noise of the device body. In particular, a digitally controlled motor is often used to load the main body of a power assisted bicycle or the like, and this smoothing circuit is indispensable in order to prevent remaining capacity calculation and display malfunction due to motor noise having a high frequency. Further, from the viewpoint of keeping the lighting light amount of the LED constant, the power supply voltage supplied to the LED needs to be obtained from a power supply line via a smoothing circuit and a regulator circuit.
Further, in order to turn on a plurality of LEDs, a current of at least about 5 mA is required for each LED. For this reason,
In addition to the voltage drop of the battery block due to the resistor Rb, LE
When D lights up, the voltage of the battery block further drops. Taking the example of a power assisted bicycle where this effect is noticeable, three LEDs out of four light up,
In other words, even when the remaining capacity of the battery is still sufficient, a large load such as running on a slope is applied to the battery block, and the battery voltage drops significantly. In addition to this, a drop in battery voltage due to the lighting of three LEDs is added. For this reason, the voltage of the battery block becomes lower than the voltage setting value for warning the battery of charge, and the LED may suddenly change from the three lighting states to the blinking charge warning display. As described above, since the charging warning is displayed even though the remaining capacity of the battery is sufficient, there is a problem that unnecessary charging is performed and the battery life is shortened.

An object of the present invention is to solve the above-mentioned problem, and an object of the present invention is to provide a battery pack capable of accurately displaying a charge request warning display regardless of the number of lighted remaining capacity display LEDs.

[0011]

In order to achieve the above object, the present invention provides a circuit comprising one or more secondary batteries, a plurality of LEDs for displaying a remaining battery capacity, and a circuit board. The remaining charge of the battery is calculated by the control circuit on the board, the remaining charge of the battery is displayed in proportion to the number of lighting of the LED by the output signal, and the battery voltage is set to be equal to or less than a preset discharge end voltage value. A battery pack that displays a warning of a charge request by an LED when the battery pack detects that the discharge end voltage has been detected, and is configured such that a control circuit on a circuit board changes a set value of a discharge end voltage according to the number of lighted LEDs. It is.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION
A battery pack having the above-described configuration, in which a control circuit on a circuit board changes a set value of a discharge end voltage in accordance with the number of lighted LEDs.

According to a second aspect of the present invention, the control circuit on the circuit board sets the discharge end voltage value of the battery in inverse proportion to the number of lights of the LED.

[0014] Thus, the warning display of the charge request can be accurately given to the battery without being affected by the lighting display of the LED. Therefore, the user can charge the battery at the right time, and can sufficiently bring out the performance of the battery pack.

[0015]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram of a battery pack 1 according to an embodiment of the present invention. In FIG. 1, a battery pack 1
Displays a battery block 2 composed of a plurality of nickel-hydrogen storage batteries, a control circuit 3 composed of an IC, a smoothing circuit composed of a resistor Rb and a capacitor C, a regulator circuit 6, a remaining capacity of the battery, and a battery charge warning display. 5 LEDs 7
It is composed of

The operation inside the battery pack 1 will be described below.

The voltage generated at the current detection resistor Ra is A-D
The data is converted into digital data by the converter 37 and sent to the remaining capacity calculator 38, where the current integration calculation is performed, and the remaining capacity of the battery is calculated. The remaining capacity of the battery is sent to the LED controller 34a. LED controller 34
“a” determines the lighting number of the LED 7 in proportion to the remaining capacity of the battery, and sends a signal to the LED 7. Receiving this signal, the LED 7 displays the remaining capacity of the battery by the number of lighting of the LED 7.

The battery voltage is divided by Rc and Rd,
The data is converted into digital data by the AD converter 31 and input to the voltage comparator 32. The voltage setting circuit 33a determines the number of lighting of the LED output from the LED controller 34a (5
, Four, three, two, one lighting), and stores the discharge end voltage value of the battery set in inverse proportion to the degree of
The discharge end voltage according to the number of lightings of D is selected. For example, when the number of lights of the LED 7 is 5 (the current value required for lighting is 25 mA), the discharge end voltage of the battery is 3.3 V.
Is selected, and when the lighting number of the LED 7 is three (the current value required for lighting is 15 mA), the discharge end voltage is 3.5 V
Select

The thus-selected discharge end voltage is compared with the battery voltage at that time by the voltage comparator 32. When the battery voltage becomes lower than the selected discharge end voltage, a charge request warning signal is issued. It is sent to the LED controller 34a. Upon receiving the charge request warning signal, the LED controller 34a blinks the five LEDs 7 to notify the user of the charging time.

[0021]

As described above, the present invention provides a plurality of LEDs.
In the battery pack which displays the remaining capacity using the LED, the control circuit on the circuit board changes the set value of the discharge end voltage of the battery according to the lighting number of the LED, thereby
Irrespective of the lighting display of, the warning display of the charging request can be accurately displayed to the user. Therefore, the user can perform charging at the correct time when the charging request is issued, and can sufficiently exert the performance of the battery pack.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a battery pack according to an embodiment of the present invention.

FIG. 2 is a block diagram showing a conventional battery pack.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Battery pack 2 Battery block 3 Control circuit 4 Device body 5 Load 6 Regulator circuit 7 LED

Claims (2)

[Claims] 1. A battery comprising one or more secondary batteries, a plurality of LEDs for displaying remaining battery capacity, and a circuit board, wherein a control circuit on the circuit board calculates the remaining capacity of the battery. The remaining capacity of the battery is displayed in proportion to the number of lightings of the LED by the output signal, and when it is detected that the battery voltage is equal to or less than a preset discharge end voltage value, the LED is detected. A battery pack for displaying a warning of a charging request by blinking of the LED, wherein a control circuit on the circuit board changes a set value of the discharge end voltage in accordance with a lighting number of the LED. 2. A control circuit on the circuit board includes:
The battery pack according to claim 1, wherein the discharge end voltage value of the battery is set in inverse proportion to the number of lighting times of the battery.