JP2003143765A - Battery pack and control method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problem in controlling the charging/discharging of a plurality of connected battery packs by battery control signals, where the plurality of battery packs cannot be controlled from a system apparatus if the plurality of battery packs have common identification information and, further, the attachment/detachment of the plurality of battery packs in operation is not taken into account. SOLUTION: Battery identification signals which provide one-to-one communications with personal computers and battery packs are provided in the battery packs in addition to battery control signals to make it possible to identify the battery packs from a system apparatus. Further, connection detection terminals of the battery packs on an upstream side and a downstream side are provided and the upstream side is informed of the characteristic information of the connected battery pack by the battery identification signal.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to charge / discharge control of a battery pack used in a portable information processing device such as a personal computer, and more particularly to charge / discharge control of a plurality of battery packs.

[0002]

2. Description of the Related Art In a battery pack that can be charged and discharged in a portable information processing device such as a personal computer, generally, with respect to one battery pack, a terminal for charging and discharging from a system device, and a ground terminal (a battery (Minus terminal), terminals for exchanging information such as battery capacity are required. For long-term battery operation, multiple battery packs are often connected to the device.In this case, the terminals for connecting the battery pack and the device are connected in proportion to the number of battery packs connected. There are many problems. In other words, when connecting two battery packs, it is necessary to prepare at least 6 terminals for the device, and when connecting two two battery packs, at least 9 terminals for the device. You need to prepare.

In the method of preparing the connection terminals of the battery pack in the apparatus according to the number of the connected battery packs as described above, the installation area of the connection terminals is required, which becomes a factor to hinder the miniaturization of the apparatus. There is also a problem that the number of connectable battery packs is limited.

For this reason, there has been proposed a method in which charge / discharge control of connected battery packs can be performed without increasing the number of connection terminals even if the number of connectable battery packs is increased. For example, in Japanese Unexamined Patent Publication No. 11-262196, charging / discharging control terminals of a battery pack and current input / output terminals of a battery are arranged in a battery pack so that the terminals can be connected in parallel, and the battery pack Coupling is disclosed. According to this, it is possible to sequentially charge a plurality of battery packs in an arbitrary order without increasing the number of connection terminals of the device, and it is possible to discharge the connected battery packs as needed. Become.

[0005]

In the above prior art, the battery packs connected in parallel control charging / discharging based on the charge control signal or the discharge control signal, and the identification of each battery pack is taken into consideration. Absent.
That is, it is premised that each battery pack has unique identification information regarding the control signal. Therefore, it is necessary to prepare battery packs having different identification information in advance, and there is a problem that the battery packs to be connected are limited.

Further, in the smart battery system used in a personal computer, the battery pack has a fixed slave address and is controlled by the controller, and it does not consider connecting a plurality of battery packs in parallel.

An object of the present invention is to provide a battery pack and a charge / discharge control method for the battery pack, in which the battery pack can be connected to perform charge / discharge without considering the identification information regarding the charge / discharge control signal of the battery pack.

[0008]

In order to solve the above problems, the battery pack of the present invention has a terminal connected to another battery pack or a battery controller of a system unit and a terminal connected to the other battery pack. And a plurality of battery packs can be connected in a plurality of stages. Further, the battery packs connected in multiple stages are connected to the system unit so that the battery control unit of the system unit can control the battery pack.

The terminal connected to the other battery pack or the battery control section of the system unit is a battery control signal for communicating an acquisition command of battery pack information such as the remaining capacity of the battery pack and an operation command of charging the battery pack. The terminal is bus-connected to the battery control unit. At this time, connect the side of the battery control unit side of the battery pack and the side of the side that connects the battery pack inside the pack, connect multiple battery packs in a daisy chain, and connect to the battery control unit of the system unit. .

The other terminal is a terminal for a battery pack identification signal which is connected to an adjacent battery pack in a one-to-one relationship and controls the identification of a plurality of battery packs from the unique information of the battery pack. It was installed on the side that connects the side and the battery pack.

The battery control signal and the battery pack identification signal are connected to a pack control unit inside the battery pack, and the back control unit controls charging and discharging of the battery based on the signals.

Further, the battery pack has a first connection detection terminal for detecting connection to the system unit or the upstream battery pack, and a connection notification terminal for notifying connection to the system unit or the upstream battery pack. A second connection detection terminal for detecting the connection of the downstream battery pack is provided. The control unit is
By inputting the connection information from the first connection detection terminal,
The connection information is output to the connection notification terminal, at least the unique information of the battery pack is notified to the system device or the upstream battery pack by the first battery pack identification signal, and the connection information from the second connection detection terminal is output. By inputting the connection information, the unique information of the downstream battery pack is acquired by the second battery pack identification signal.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described in detail below with reference to the drawings. 1 and 2 are diagrams showing an embodiment of the present invention. FIG. 1 is a diagram in which a system device 1 for charge / discharge control is connected to battery packs 14 and 17 in which a secondary battery is incorporated. The battery packs 14 and 17 have the same circuit configuration and are shown in FIG. Also, the battery pack connecting connectors 12, 15, 18 have the same shape,
The connectors 13 and 16 also have the same shape.

In FIG. 1, the battery pack 14 is connected to the system unit 1, the battery pack 17 is connected to the battery pack 14, but the battery pack 17 is connected to the system unit 1 and the battery pack 14 is connected to the battery pack 17. It has a structure that can be connected. Also,
Similarly, it is possible to connect multiple battery packs to the rear.

The power supply circuit 3 of the system unit 1 is a circuit for supplying power to the system unit 1. When power is supplied from the outside, such as an AC adapter, the FET (5) is controlled by the microcontroller (hereinafter abbreviated as "microcomputer") 2 to charge the battery pack. If there is no power supply from the outside such as AC adapter, control the FET6 with the microcomputer 2,
Discharge from the battery pack.

Each of the battery packs 14 and 17 has a battery 23 for supplying power to a system device and the like, and the state of the battery is monitored by the microcomputer 24. Further, in the case of overcharging, the FET 22 is turned off to prevent charging, and in the case of overdischarging or not connected to the system unit or the battery pack, the FET 21 is turned off. Whether or not it is connected to the system unit and the battery pack is pulled up when the connection recognition signal 10 is not connected and becomes LOW by connecting, so the microcomputer 24 monitors the signal and the system and It recognizes that it is connected to the battery pack. The overcharge prevention FET 22 is normally turned off, and is turned on when data for instructing to start charging is transmitted from the system device. Even when the charging is stopped again, it is turned off when the data of the instruction to stop the charging is transmitted from the system device. The over-discharging prevention FET 21 is normally turned on and turned off when data for instructing to stop discharging is transmitted from the system device. Also, the over-discharge prevention FET 21 is turned on by transmitting the data of the instruction to start the discharge from the system device.

The number and the identification number of the connected battery packs are recognized by the control and information acquisition signal (SMBus1 signal) 9 connected in parallel with the control and information acquisition signal (SMBus2 signal) connected in parallel. ) 8 controls the battery and acquires information. In this embodiment, it is assumed that the communication is SMBus, but other communication methods may be used. If multiple batteries are connected at the same time,
The connection recognition signal 7 allows the system unit 1 to recognize that the battery is connected. Next, when the battery is connected from the system unit 1, via the SMBus1 communication signal 9, the battery pack in the rear and all models of batteries connected to the rear of the battery pack and serial numbers (in the memory in the microcomputer 24 of the battery pack) Get all stored). (Refer to the flow in Fig. 3) Battery pack 1
When the battery pack 17 at the rear of 4 is connected, the front microcomputer at that time acquires information based on the rear microcomputer and the SMBus1 communication signal. For example, when the battery pack 17 is connected to the battery pack 14, first, it is recognized that the microcomputer 24 of the battery pack 14 is connected by the connection recognition signal 26. Next, the model and serial number are acquired from the microcomputer 24 of the battery pack 17 via the SMBus1 signal 25. In this embodiment, it is assumed that the control is performed by the model and serial number, but other identification numbers may be used.
The microcomputer 24 of the battery pack 14 stores the information. (Refer to the flow of FIG. 4) It should be noted that the connection of the battery pack 14 to the system unit 1 and the connection of the battery pack 17 to the battery pack 14 are almost simultaneous or the system unit 1 is connected to the battery pack 17 to the battery pack 14. If it is late to connect, the microcomputer 24 of the battery pack 14 is the model and serial number of all battery packs.
After the memory of is completed, turn off SW19 and turn it on again. (Thus, the system unit 1 recognizes that the connection has been updated.) The system unit 1 acquires the model numbers and serial numbers of all the battery packs connected by the SMBus1 communication signal 9. In this way, the model and serial number of the connected batteries can be known, and the number of connected batteries and the order of connection can be known.

When acquiring information such as the charge / discharge capacities and charge conditions of the battery packs 14 and 17, the system unit 1 always operates as a master for communication switching of each battery pack so that the data of the SMBus2 communication signal 8 does not always collide.
SW27 prevents data from colliding with each other. For example, when the batteries 14 and 17 are connected and the battery status data of the battery 17 is read and then the battery status data of the battery 14 is read, first, the microcomputer 2 of the system unit 1 sends the SMBus1 signal.
Send the model and serial number of the battery pack (battery pack 14) whose battery status you want to read via 9. Receiving the data, the microcomputer 24 of the battery pack 14 recognizes that the model and serial number indicate the battery pack 14, and turns on SW27 to connect the microcomputer 24 to the SMBus2 signal 8. Then, microcomputer 2 of PC 1
Reads the model and serial number via the SMBus2 signal 8, and if the model and serial number of the battery pack 14 can be read, it recognizes that communication has been established, and the battery status data of the battery pack 14 is sent to the SMBus2 signal. Read at 8. Next, when the reading of the battery pack 14 is completed, the data of the instruction to stop the SMBus2 signal is transferred via the SMBus2 signal 8. Based on this data, the battery pack microcomputer 24
Turns off SW27. (See the flow chart of FIG. 5) Next, the microcomputer 2 of the system unit 1 transmits the model and serial number of the battery pack (battery pack 17) from which the battery status data is to be read by the SMBus1 signal 9. The microcomputer 24 of the battery pack 14 that received the data is not the model and serial number of the battery pack 14, so SMB
The type of battery pack (battery pack 17) you want to read to the microcomputer 24 of the battery 17 with the us1 signal 25, serial
Send the No. As a result, the microcomputer 24 of the battery pack 17 recognizes the model and serial number of the battery pack 17, and turns on SW27 to connect the SMBus2 signal 8 to the microcomputer 24. After that, the battery status data is read in the same manner as the battery pack 14. In this way, it is possible to acquire information accurately without collision of communications.

For charging control, SMBus2 signal 8 from the personal computer
Since the charging start is transmitted after the charging start is transmitted to the battery pack to be charged at, the charging can be started from the back or the battery pack to be charged can be freely charged. Also, simultaneous charging is possible by sending charging start data to a plurality of batteries. For example, when the battery pack 14 is charged, first, the SMBus2 signal 8 is connected to the microcomputer 24 of the battery pack 14 as in the acquisition of the battery pack information, and the charging start data is transmitted to the battery pack 14. The microcomputer 24 of the battery pack 14 that has received it turns on the overcharge prevention FET 22. (Usually the charge FET 22 is off) Next, the battery pack
The charging conditions of 14 are read, the charging FET 5 of the personal computer is turned on, and charging is started by the charging circuit 4. The battery information of the battery pack 14, is periodically acquired, and the charging control suitable for it is performed. When the battery is fully charged, the charging stop data is communicated via SMBus2 signal 8. As a result, the overcharge prevention FET 22 in the battery pack is turned off.
(See the flow chart in FIG. 6) This completes the charging.

In the discharge control, the over-discharge prevention FET 21 is incorporated in the microcomputer so that it can be discharged at any time after being connected to the system unit or the battery pack.
Therefore, in the normal initial state, the connected battery packs are simultaneously discharged. However, by sending SMBus2 signal 8 to each battery pack to stop discharging data, and to send discharging start data again, you can turn on / off FET21 for over-discharge prevention to discharge in the same manner as charge control. The battery pack can be set.

[0021]

As described above, according to the present invention, the acquisition of the identification numbers of a plurality of connected battery packs, the acquisition of the battery status information, and the charging / discharging control of the battery selected by the user can be performed. It is possible to use a battery pack having the same identification number, which is effective in reducing the cost of the battery pack.

[Brief description of drawings]

FIG. 1 is a diagram showing a connection between a system device and a battery pack according to an embodiment of the present invention.

FIG. 2 is a configuration diagram showing the inside of a battery pack according to an embodiment of the present invention.

FIG. 3 is a flowchart for reading the model names and serial numbers of all the battery packs connected in the embodiment of the present invention.

FIG. 4 is a flow chart when connecting battery packs in an embodiment of the present invention.

FIG. 5 is a flowchart for reading the state of the battery pack, the charging conditions, etc. in the embodiment of the present invention.

FIG. 6 is a flow chart of charging control of a battery pack according to an embodiment of the present invention.

[Explanation of symbols]

1 ... System unit, 2 ... Microcomputer, 3 ... Power supply circuit 4 ... Charging circuit, 5 ... Charging FET, 6 ... Discharging FET, 7 ... Battery pack connection recognition signal, 8 ... SMBus1 signal, 9 ... SMBus2 signal,
10 ... System unit and battery pack connection recognition signal,
11 ... GND, 12 ... connector, 13 ... connector, 14 ...
Battery pack, 15 ... Connection connector, 16 ... Connection connector, 17 ... Battery pack, 18 ... Connection connector, 19 ... Connection signal SW, 20 ... Current sense resistor, 21 ... Over discharge prevention FET, 22
… FET for overcharge prevention, 23… Secondary battery, 24… Microcomputer, 25…
SMBus1 signal, 26 ... Battery pack connection recognition signal,
27 ... SMBus2 signal SW, 28 ... System unit and battery pack connection recognition signal

   ─────────────────────────────────────────────────── ─── Continued front page    F term (reference) 5B011 DA06 DA13 DB21 DB26 DC06                       EA04 HH02                 5G003 AA01 BA03 CA01 CA11 DA07                       DA18 FA07 GA01 GC05                 5H030 AA06 AS11 BB01 BB21 FF41                 5H040 AA39 AS12 AY04 DD06 DD16

Claims (6)

[Claims] 1. A battery pack which has a terminal connected to another battery pack or a battery control unit of a system unit and a terminal connected from another battery pack, and which can be connected in a plurality of stages. Bus connection to the terminal, and the terminal of the battery control signal that communicates the operation command such as the acquisition command of the battery pack information such as the remaining capacity of the battery pack and the charging command of the battery pack, and the one-to-one connection with the adjacent battery pack, Two terminals of the battery pack identification signal for controlling the identification of a plurality of battery packs from the unique information of the battery pack,
A battery pack comprising: a battery pack control unit that performs battery charge / discharge control and communication with the battery control unit based on the battery control signal and the battery pack identification signal. 2. The pack control unit, when a plurality of battery packs connected to the battery control signal have common identification information regarding the battery control signal,
The battery pack according to claim 1, wherein the battery pack communicates with the battery control unit based on an instruction of the battery pack identification signal. 3. A first connection detection terminal for detecting connection to a system device or an upstream battery pack, a connection notification terminal for notifying connection to a system device or an upstream battery pack, and a downstream battery pack. Second to detect that the
A connection detection terminal of the, the control unit, by the input of the connection information from the first connection detection terminal,
The connection information is output to the connection notification terminal, and at least the unique information of the battery pack is notified to the system device or the upstream battery pack by the first battery pack identification signal, and the connection information from the second connection detection terminal is output. By entering the connection information,
The battery pack according to claim 1, wherein the unique information of the downstream battery pack is acquired by the second battery pack identification signal. 4. A method of controlling a battery pack, which can be connected to another battery pack or a battery control unit of a system unit in a plurality of stages and is controlled by a command from the battery control unit, wherein each battery pack is unique. The battery control unit is notified of information, the battery control unit identifies the battery pack based on the unique information, and the identified battery pack is controlled by a command from the battery control unit. Battery pack control method 5. When the connection of the downstream battery pack is detected, the unique information of the downstream battery pack is acquired, and when the connection to the system device or the upstream battery pack is detected, the connection notification information and at least the battery concerned. The method of controlling a battery pack according to claim 4, wherein the system unit or the upstream battery pack is notified of the unique information of the pack. 6. When the battery pack is connected to an upstream battery pack or a system device and then a downstream battery pack is connected, unique information is obtained from the downstream battery pack and the upstream battery pack or the system device is connected. 6. The battery control unit is notified of the connection information, and the unique information of the battery pack and the acquired downstream battery pack is also notified to the upstream battery pack or the battery control unit of the system device. Battery pack control method.