JP2003070172A - Multi battery system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable system maintenance on a minimum level by the use of batteries on the side where residual quantity is small even when a battery with a sufficient residual quantity is pulled out by mistake, in a multiple battery system with a plurality of batteries which can individually operate an electronic equipment for a long time. SOLUTION: When a system can be maintained even if the residual quantity of a certain battery is lower than a standard value and another battery charges other battery at fixed quantity, the charging between batteries from another battery to one certain battery is carried out with a rate at which one certain battery can at least maintain the system by itself.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multi-battery system having a plurality of batteries including detachable batteries and electronic equipment which can be driven by connecting the batteries individually. More specifically, in a system including a plurality of batteries, within a certain period of time, for example, the time required to replace the battery or the time required for the system to record data and normally terminate the power supply. If there is a battery that has no remaining capacity to enable system operation, check that the remaining capacity of the other battery is above a certain level, and if it is above a certain level, the system can be operated from the other battery within a certain time This is related to a multiple battery system in which the energy loss due to charging is minimized by charging only the capacity to be used, and the system does not go down even if the battery with the capacity is removed. is there.

[0002]

2. Description of the Related Art Japanese Utility Model Application Laid-Open No. 60-183996 (name: "portable electric equipment") discloses that a system consisting of a main battery and an auxiliary battery normally charges the auxiliary battery from the main battery. , A technique that prevents the system from going down when the main battery is replaced is disclosed. However, this publication does not describe a case where a plurality of batteries are both main batteries, that is, each battery alone can operate for a long time. Further, no consideration is given to the amount of charge of the battery, and there is no description about performing the minimum charge necessary for replacement in consideration of energy loss in charging between batteries.

Further, in Japanese Patent Laid-Open No. 7-154924 (name: "Battery usage method of portable electronic device"), in an information device equipped with two types of batteries having different characteristics, the driving condition of the device, that is, the load. There is disclosed a technique in which a large-capacity battery is charged to a normally used battery in accordance with the above, thereby making the best use of the characteristics of each battery to prolong the life of the total driving time. However, this publication does not mention a method of preventing the system from going down when replacing a replaceable battery.

[0004]

In the above-mentioned prior art, there are a plurality of batteries capable of individually operating the electronic device for a long time, and one of them has a remaining capacity capable of operating the electronic device, In the case where one of them has a state of charge that makes it impossible to operate the electronic device, if a battery having a state of charge that can be operated is accidentally removed, the system will go down. In order to solve this problem, there is a method of installing an auxiliary battery, and when replacing the battery, the auxiliary battery supplies power for a very short time to prevent the system from going down, but in this case, it is usually used for electronic devices. Since the auxiliary battery is not installed, there are problems that the electronic device becomes large and the cost increases.

An object of the present invention is to provide a multi-battery system having a plurality of batteries capable of individually operating electronic devices for a long time, even if a battery with a high remaining amount is accidentally removed. A battery with a small amount can drive an electronic device during a time when the battery can be replaced, or save data of the electronic device and normally terminate the electronic device.

[0006]

In order to achieve the above object, in a typical invention of the present application, an electronic device using a battery as a driving power source and an electronic device of the electronic device are individually connected to each other. A plurality of batteries including a detachable battery that can be driven, a plurality of connection parts provided in the electronic device that can connect the plurality of batteries, a discharge path of the plurality of batteries, and A plurality of remaining capacity detecting means for detecting respective remaining capacities of the plurality of batteries, and a charging current limiting resistor for enabling charging between the batteries between discharge paths of the plurality of batteries, and a backflow prevention diode for preventing erroneous charging. , Charging ON / OFF
An inter-battery charging circuit including control FETs, and ON / O switching of the FETs according to the remaining capacities of the plurality of batteries.
Charging control means capable of FF control, wherein the state of the remaining capacity of one battery falls below a predetermined reference value, and the state of remaining capacity of another one battery is different. If the system maintenance can be guaranteed even after the battery is charged to a predetermined amount, the certain one battery independently operates the system for a certain time from the other certain battery to the certain one battery. To be able to maintain
It is configured to allow inter-battery charging.

By adopting such a configuration, in a multi-battery system having a plurality of batteries capable of individually operating the electronic equipment for a long time, a plurality of batteries having different remaining capacities are mounted. Even if the battery with the high remaining capacity is accidentally removed, the battery with the low remaining capacity drives the electronic device during the time when the battery can be replaced, or saves the data of the electronic device and saves the electronic device. It becomes possible to end normally.

Characteristic configurations of the present invention other than those described above and their effects will be apparent from the following description.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram of a multiple battery system according to a first embodiment of the present invention. In each of the embodiments of the present invention including the present embodiment, the system is roughly divided into a battery pack 1, a battery pack 2, and an electronic device 3, and a battery pack 1 including a battery cell 11, and a battery cell. The battery packs 2 each having the built-in 21 are attachable to and detachable from the electronic device 3 (note that the battery cells may be replaceable). When the battery level is sufficient, either the battery pack 1 or the battery pack 2 alone
The electronic device 3 can be driven for a long time.

The electronic device 3 includes the connection portion 31 of the battery pack 1, the connection portion 32 of the battery pack 2, the discharge path 33 from the battery pack 1, the discharge path 34 from the battery pack 2, and the battery pack 2. An inter-battery charging circuit A35 for charging the battery pack 1, an inter-battery charging circuit B36 for charging the battery pack 1 to the battery pack 2, and a backflow prevention diode 3
7, a backflow prevention diode 38, an electronic device and other circuit section 39, a battery remaining amount detection circuit 300 that detects the remaining capacity of the battery pack 1, and a battery remaining amount detection circuit 303 that detects the remaining capacity of the battery pack 2. Is equipped with.

The battery-to-battery charging circuit A35 includes a bleed resistor (charging current limiting resistor) 351 for preventing damage to the battery, a backflow prevention diode 352 for preventing erroneous charging, and a charging ON / OFF control. FE
T353 and the inter-battery charging circuit B36
Includes a bleed resistor (charging current limiting resistor) 361 that does not damage the battery, a backflow prevention diode 362 that prevents erroneous charging, and a charge ON / OFF control FET 363.

The potential device and other circuit section 39 is provided with a battery control microcomputer 391. The battery control microcomputer 391 has a battery level notification signal 301 from the battery level detection circuit 300 and a battery level detection circuit. Thirty
The remaining amount notification signal 304 from 3 is input. Then, the battery control microcomputer 391 monitoring the remaining amount notification signals 301 and 304 performs charge control between the batteries based on an algorithm described later, and the inter-battery charging circuit A35 has a charge ON / OFF signal A354.
Is output, and charging is turned on / on the inter-battery charging circuit B36.
The OFF signal B364 is output.

Before explaining the specific operation, the state of the remaining battery level, which serves as a basis for determining the start / stop of inter-battery charging, will be described. For simplification of description, the remaining battery level is classified into three states, that is, the remaining battery level A, the remaining battery level B, and the remaining battery level C, as shown in FIG. I decided to.

The battery remaining amount state A means that the system is driven for a certain period of time when the remaining amount of the battery is very small and the other battery is removed while the electronic device 3 is operated by a plurality of batteries. It refers to the remaining amount that cannot be met. The certain time period means a time period required to replace the removed battery, or a time period required to save the data being operated by the electronic device and normally turn off the electronic device. The battery remaining amount state A means a remaining amount level that requires inter-battery charging from the other.

The battery remaining amount state B is equal to or higher than the battery remaining amount state A, but when the other battery in the battery remaining amount state A is charged to reach the battery remaining amount state B or higher, the remaining amount of its own battery This means that the state becomes the remaining battery state A, that is, the inter-battery charging from the other battery is not required, but the remaining battery cannot be charged to the remaining battery level.

The remaining battery state C is equal to or higher than the remaining battery state A, and the other battery is in the remaining battery state B.
Even if the battery is charged more than the above, it means that the battery itself can be maintained at the battery residual amount state B or higher, that is, the other battery has a residual amount level capable of inter-battery charging.

A detailed description of the operation will be given based on the above three remaining states.

The power supply current from the battery pack 1 passes through the discharge path 33 and is supplied to the electronic device and other circuit section 39 through the backflow prevention diode 37. Similarly, the power supply current from the battery pack 2 is discharged. 34, and through the backflow prevention diode 38, electronic device and other circuit section 3
9, so that power is supplied to the electronic device 3. At this time, the remaining amounts of the battery pack 1 and the battery pack 2 are respectively detected by the battery remaining amount detection circuit 300 and the battery remaining amount detection circuit 303, and the remaining amounts are respectively detected from the battery remaining amount detection circuit 300 and the battery remaining amount detection circuit 303. Notification signal 301,
The battery level notification signal 304 indicates that the battery control microcomputer 391
To be constantly or regularly communicated to.

The battery control microcomputer 391 recognizes the remaining amounts of the battery pack 1 and the battery pack 2 from the remaining amount notification signal 301 and the remaining amount notification signal 304, and determines whether the current state is a state in which inter-battery charging is required. Further, it is determined whether the current state is a state where inter-battery charging is possible, and if necessary and possible, inter-battery charging control using the inter-battery charging circuit A35 or the inter-battery charging circuit B36 is performed.

FIG. 3 shows a control processing flow of inter-battery charging of the battery control microcomputer 391.

First, in step S1, it is determined whether or not the state of the battery pack 1 is the remaining battery state A, and if it is the remaining battery state A, the process proceeds to step S2, and if not, step S6. Go to. In step S2, it is determined whether or not the state of the battery pack 2 is the battery remaining amount state C, and if it is the battery remaining amount state C, the process proceeds to step S3, and if not, inter-battery charging cannot be performed. Then, the process proceeds to step S11, and the inter-battery charging is not performed. In step S3, the battery pack 2 is charged to the battery pack 1,
In step S4, it waits for the state of the battery pack 1 to come out of the battery remaining amount state A (that is, waits for the state of the battery remaining amount state B), and when the state of the battery pack 1 leaves the battery remaining amount state A. In step S5, the charging operation from the battery pack 2 to the battery pack 1 is stopped.

In step S6, it is determined whether or not the state of the battery pack 1 is the battery residual amount state C. If the battery residual amount state C is determined, the process proceeds to step S7. If not, inter-battery charging is performed. If it cannot be performed, the process proceeds to step S11. In step S7, it is determined whether or not the state of the battery pack 2 is the remaining battery state A, and if it is the remaining battery state A, then step S8.
If not, it is determined that inter-battery charging is not necessary, and the process proceeds to step S11. In step S8, the battery pack 1 is charged to the battery pack 2, and in step S9, it waits for the state of the battery pack 2 to come out of the battery remaining amount state A (that is, to reach the battery remaining amount state B. Waiting), when the state of the battery pack 2 is released from the battery remaining amount state A, step S10
At, the charging operation from the battery pack 1 to the battery pack 2 is stopped.

In this way, the battery control microcomputer 391
Is a combination of the remaining battery level of the battery pack 1 and the remaining battery level of the battery pack 2,
Only in the case of, the control is performed such that the battery pack side in the battery remaining amount state C charges the battery pack in the battery remaining amount state A.

As a specific circuit operation at the time of charging between batteries, when it is desired to charge the battery pack 1 from the battery pack 2, the charge ON / OFF signal A354 is changed from low to high to control the charge ON / OFF. FET35
By making 3 electrically conductive, the inter-battery charging circuit A35
To turn on. The inter-battery charging circuit A35 prevents a large current from flowing by limiting the charging current with the bleed resistor 351, and performs charging with a safe charging current. The backflow prevention diode 352 serves to prevent backflow charge from the battery pack 1 to the battery pack 2 in the inter-battery charging circuit A35.

Even during charging from the battery pack 2 to the battery pack 1, the battery remaining amount of the battery pack 1 is detected by the battery remaining amount detection circuit 300, and this is transmitted to the battery control microcomputer 391 as the remaining amount notification signal 301, and the battery is controlled. When the pack 1 reaches the battery remaining state B, the charging ON / OFF signal A354 is returned to low,
The inter-battery charging circuit A is turned off and the inter-battery charging is stopped.

As a result, even if the battery pack 2 is removed by charging the battery pack 1 that did not retain the power for maintaining the system with the minimum required energy from the battery pack 2. The system can be maintained, and
It is possible to minimize power loss due to charging between batteries.

The operation of the inter-battery charging circuit B36 when charging the battery pack 1 to the battery pack 2 is similar to that of the inter-battery charging circuit A35.

FIG. 4 is a block diagram of a multiple battery system according to the second embodiment of the present invention. In FIG.
The same parts as those in the previous embodiment are designated by the same reference numerals, and the description thereof will be omitted to avoid duplication (this also applies to the following embodiments).

The present embodiment differs from the first embodiment in that the battery remaining amount detection circuit 300 and the battery remaining amount detection circuit 303 are removed from the electronic device 3 side, and the battery remaining amount detection circuit 300 is located on the battery pack 1 side. And the battery remaining amount detection circuit 303 is provided in the battery pack 2. The operation of the system is the same as that of the first embodiment, but the remaining amount notification signal 301 and the remaining amount notification signal 304 are output to the battery control microcomputer 39 via the connection unit 31 and the connection unit 32, respectively.

In the first embodiment, the means for detecting the remaining capacity of the battery is provided on the electronic device 3 side. However, when it is desired to reduce the size of the electronic equipment, the means for detecting the remaining capacity of the battery is provided on the battery side. It is advantageous to provide a battery remaining amount monitoring IC or the like. The present embodiment is an application example from such a viewpoint, and can contribute to reducing the size of the electronic device.

FIG. 5 is a block diagram of a multiple battery system according to a third embodiment of the present invention. The present embodiment differs from the second embodiment in that the inter-battery charging circuit A
35, the inter-battery charging circuit B36 disappears from the electronic device 3 side, and the inter-battery charging circuit A35 becomes the battery pack 1.
The inter-battery charging circuit B36 provided on the side is provided on the battery pack 2. The operation of the system is the same as that of the first embodiment, but the charging circuits 35 and 36 between both batteries are connected to the electronic device 3 by the connecting portions 31 and 3.
2. Connected via the discharge paths 33 and 34, the remaining amount notification signal 301, the remaining amount notification signal 304, the charging ON / OFF signal A 354, and the charging ON / OFF signal B 364 are respectively connected via the connection part 31 and the connection part 32. Battery pack 1,
2 is exchanged between the electronic device 3 and the electronic device 3.

In the second embodiment, the battery remaining capacity detecting means is provided on the battery side. However, if it is desired to further reduce the size of the electronic device, in addition to this, a bleed resistor, a backflow prevention diode, and charging ON / OFF are added. F for OFF control
It is more advantageous to provide the inter-battery charging circuit composed of ET on the battery side. The present embodiment is an application example from such a viewpoint, and can contribute to further reducing the size of the electronic device.

FIG. 6 is a block diagram of a multiple battery system according to a fourth embodiment of the present invention. This embodiment is different from the third embodiment in that the battery control microcomputer 391 disappears from the electronic device 3 side, and the battery pack 1
It's on the side. Regarding the operation of the system,
Although it is equivalent to the first embodiment, the both-battery charging circuits 35 and 36 are connected via the connection portions 31 and 32 and the discharge paths 33 and 34 on the electronic device 3 side, and the remaining amount notification signal 30 is transmitted.
4. The charge ON / OFF signal B364 is transmitted and received between the battery pack 1 and the battery pack 2 via the connection part 31 and the connection part 32 (via the electronic device 3), respectively.
Remaining charge notification signal 301, charge ON / OFF signal A354
Are exchanged in the battery pack 1.

In the third embodiment, the battery remaining capacity detecting means and the inter-battery charging circuit are provided on the battery side. However, if it is desired to further reduce the size of the electronic device, in addition to this, the battery control microcomputer also has a battery. It is more advantageous to manage the power supply system from the battery side by providing the battery side with intelligence and the battery side with intelligence. The present embodiment is an application example from such a viewpoint, and can contribute to further reducing the size of the electronic device.

FIG. 7 is a block diagram of a multiple battery system according to a fifth embodiment of the present invention. The present embodiment is different from the fourth embodiment in that a battery control microcomputer 391 is replaced with a charge control circuit 40 for voltage comparison such as a comparator. The basic operation of the system is the same as that of the first embodiment, but the voltages of the battery pack 1 and the battery pack 2 are monitored, and the respective voltages are compared by a voltage comparison circuit such as a comparator to perform inter-battery charging. If it is the voltage difference to be performed, the inter-battery charging circuit A35 or the inter-battery charging circuit B36 is driven.

In the first to fourth embodiments, the battery control microcomputer is used for controlling the inter-battery charging circuit, but in the present embodiment, a relatively expensive microcomputer is used in place of a comparator or the like. Since it is an inexpensive charge control circuit that performs control by voltage comparison (controls by hardware), it can contribute to lowering the system price.

In each of the above-described embodiments, the Nch power FE is used as an element for controlling the charging ON / OFF.
Although the structure using T is used, the same effect can be obtained by using a Pch power FET. Further, by using the switch element instead of the FET, it is possible to omit the backflow prevention diode provided in the inter-battery charging circuit.

Further, in each of the above-described embodiments, the case where both of the plurality of batteries are removable has been described, but when only one of the batteries is removable, the battery is charged to the non-removable side. Only by installing the inter-battery charging circuit, the same effect can be obtained.

Further, as shown in FIG. 8, the role of the reverse current prevention diode provided in the battery charging circuit is
By replacing the inter-battery charging circuit, which has been two in the description of each embodiment, with one bi-directionally controllable battery-to-battery charging circuit, the number of parts can be reduced. Is.

[0041]

As described above, according to the present invention, in a multiple battery system having a plurality of batteries capable of individually operating electronic devices for a long time, a plurality of batteries having different remaining capacities are mounted. Even if the battery with the high remaining capacity is accidentally pulled out at this time, the battery with the low remaining capacity will drive the electronic device during the time when the battery can be replaced, or save the data of the electronic device. It is possible to end the electronic device normally.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a multiple battery system according to a first embodiment of the present invention.

FIG. 2 is an explanatory diagram showing remaining battery charge states A, B, and C used in the description of the embodiment of the present invention.

FIG. 3 is a flowchart showing a control processing flow of a battery control microcomputer in the first embodiment of the present invention.

FIG. 4 is a block diagram showing a configuration of a multiple battery system according to a second embodiment of the present invention.

FIG. 5 is a block diagram showing a configuration of a multiple battery system according to a third embodiment of the present invention.

FIG. 6 is a block diagram showing a configuration of a multiple battery system according to a fourth embodiment of the present invention.

FIG. 7 is a block diagram showing a configuration of a multiple battery system according to a fifth embodiment of the present invention.

FIG. 8 is a circuit diagram showing an example in which two inter-battery charging circuits are integrated.

[Explanation of symbols]

1 battery pack 1 11 Battery cell 1 2 battery pack 2 21 battery cell 21 3 electronic devices 31 Connection 32 connection 33 discharge path 34 Discharge path 36 Battery-to-battery charging circuit A 351 bleed resistor 352 Backflow prevention diode 353 FET for charge ON / OFF control 354 Charge ON / OFF signal A 36 Battery-to-battery charging circuit B 361 bleed resistor 362 Backflow prevention diode 363 FET for charge ON / OFF control 364 Charge ON / OFF signal B 37 Backflow prevention diode 38 Backflow prevention diode 39 Electronic devices and other circuits 391 Battery control microcomputer 40 Voltage comparison control circuit with comparator etc.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) H01M 10/48 G06F 1/00 333D F term (reference) 5B011 DA07 DA13 DB21 DC06 EA04 EA10 GG04 GG14 5G003 AA04 BA04 DA04 DA18 EA06 FA08 GC05 5H030 AA03 AA04 AA06 AA08 AS11 BB01 BB08 BB22 DD08 DD09 FF41 FF43 FF44 5H040 AA06 AA23 AA40 AS11 FF07 GG01 GG06 GG09 NN05

Claims (7)

[Claims] 1. An electronic device using a battery as a drive power source, a plurality of batteries including a detachable battery, each of which is capable of driving the electronic device by individually connecting the electronic device, and the plurality of batteries. A plurality of connecting parts provided in the electronic device that can be connected, a discharge path of the plurality of batteries, a plurality of remaining capacity detecting means for detecting respective remaining capacities of the plurality of batteries, and the plurality of batteries An inter-battery charging circuit including a charging current limiting resistor, a backflow prevention diode for preventing erroneous charging, and an FET for controlling charging ON / OFF, which enables charging between the batteries between the discharging paths of the plurality of batteries. Depending on the remaining capacity, O of the FET
Charge control means capable of N / OFF control, wherein the charge control means has a state of remaining capacity of one battery less than a predetermined reference value, and a state of remaining capacity of another one battery. If one can charge the other to a certain amount and still be able to guarantee the system maintenance, then the one battery alone will be able to charge the system from the other one battery to the one battery. A multiple battery system characterized in that charging between batteries is performed so that the battery can be maintained for a certain period of time. 2. The multiple battery system according to claim 1, wherein the charge control means is a microcomputer. 3. The multiple battery system according to claim 2, wherein the microcomputer is provided on the electronic device side. 4. The multiple battery system according to claim 2, wherein the microcomputer is provided on the battery side. 5. The multiple battery system according to claim 1, wherein the remaining capacity detecting means is provided on the battery side. 6. The battery according to claim 1, wherein the inter-battery charging circuit is provided on a battery side, and the inter-battery charging circuit is connected via the electronic device. Multiple battery system. 7. The charge control means according to claim 1, wherein the charge control means is composed of an electronic circuit that compares the voltages of the plurality of batteries and controls the inter-battery charge by hardware. Battery system.