JPH10223262A - Secondary battery pack - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely prevent discharge, even if a charging positive side outer terminal and negative side outer terminal, and/or a discharging positive side outer terminal and negative side outer terminal are repeatedly or accidentally short-circuited by office supplies, such as a clip. SOLUTION: This secondary battery pack has one or more secondary batteries 21 in a casing, and outer terminals 31a, 32a, 31b, 32b for charging and discharging the secondary battery 21 in the outer specified positions of the casing. A switch 6, which is mounted on either one of an appliance operated with the secondary battery pack and a charger, is arranged in a midway position of wiring, electrically connecting the secondary battery 21 and the outer terminals 31a, 32a, 31b, 32b.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a secondary battery pack, and more particularly, to a secondary battery pack used as a power supply for operating portable equipment such as a portable telephone and a notebook personal computer.

[0002]

2. Description of the Related Art Conventionally, a secondary battery pack having a configuration shown in FIG. 4 is generally used as a power supply for operating a portable device. This rechargeable battery pack
The casing 1 has two rechargeable battery cells 21 and 22, and has external terminals 31 and 32 for charging and discharging on the surface of the casing 1.
2 and a protection circuit 5 controlled by the protection IC 4.

Although various types of secondary battery cells 21 and 22 can be used, in recent years, lithium ion secondary batteries are often used. The secondary battery cells 21 and 22 are connected to each other in series. However, depending on the output voltage, output current, and the like required for the secondary battery pack, the number of secondary battery cells can be three or more, and the series connection and the parallel connection should be appropriately combined. Is possible.

One terminal of each of resistors 51, 52, and 53 is connected to a negative terminal and a positive terminal of the whole secondary battery cell connected in series with each other, and a connection point of both secondary battery cells. , And between the other terminals of the resistors 52 and 53, the capacitors 54 and 55 are connected, and one terminal of the resistor 56 is connected to the negative side external terminal 31, and the resistors 51, 52, 53 and 56 are connected. Is connected to the input terminal of the protection IC 4.

A fuse 57 for interrupting an overcurrent is connected in the middle of the wiring for electrically connecting the positive terminal and the external terminal 32 on the positive side as the whole secondary battery cell connected in series with each other. An over-discharge control FET 58 and an over-charge control FET 59 are connected in series with each other at an intermediate portion of the wiring for electrically connecting the negative terminal and the negative external terminal 31 of the whole series connected secondary battery cell. ing. And
The output signal output from the output terminal of the protection IC 4 is supplied to the gate terminals of the FETs 58 and 59.

Further, a lithium ion secondary battery cell 2
Each of the first and the second has a pressure cutoff switch and an overheat cutoff mechanism therein, as is conventionally known. FIG. 5 is a schematic diagram showing a simplified electrical configuration of the secondary battery pack having the above configuration. In FIG. 5, the protection IC 4, the fuse 57 for cutting off the overcurrent, the FET 58 for controlling overdischarge, and the FET 59 for controlling overcharge are simply shown as the protection circuit 5. In addition, as the external terminals 31 and 32, charging terminals 31a and 32a and discharging terminals 31b and 32b are shown.

Therefore, the charge / discharge current and voltage can be controlled within allowable ranges, and the secondary battery pack can be used without danger.

[0008]

However, in a secondary battery pack, an external terminal for connecting to a portable device body and a charger is provided in an exposed state, and a positive external terminal for charging and a negative terminal for charging are provided. Since the external terminals are arranged in parallel and close to each other, and the positive external terminal for discharge and the negative external terminal are arranged in parallel and adjacent to each other, they are erroneously placed by metal office supplies such as clips. There is a possibility that these two terminals are short-circuited. When a short circuit occurs due to such a cause, the protection IC 4 detects an overcurrent and controls the overdischarge control FET 58 to stop the discharge. In the case where the operation continues for a long time, when an abnormal state such as a case where the short-circuit state is repeated occurs, the above-described protection circuit may not operate sufficiently. Therefore, the secondary battery pack has a cautionary note indicating that the external terminals should not be short-circuited.

Nevertheless, there is a high possibility that these two terminals are short-circuited by mistake due to metal office supplies such as clips or the like, and if the short-circuit state continues for a long time, the short-circuit state is repeated. Since the case appears with considerable possibility, there is a problem that the protection in the event of a short circuit by the protection circuit of the secondary battery pack is not always perfect.

[0010]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has been made between a positive external terminal for charging and a negative external terminal and / or a positive external terminal for discharging and a negative external terminal. Provided is a secondary battery pack that can reliably prevent discharge even if terminals are short-circuited erroneously for a long time or repeatedly by metal office supplies such as clips between terminals. It is intended to be.

[0011]

According to a first aspect of the present invention, there is provided a secondary battery pack having at least one secondary battery in a casing, and charging and discharging the secondary battery at a predetermined position on an outer surface of the casing. A device having a secondary battery pack as an operation power source, a charger, which has an external terminal for performing the operation, and in the middle of wiring for electrically connecting the secondary battery and the external terminal. Has a switch that is turned on under the condition that the switch is mounted on one of the switches.

[0012]

According to the first aspect of the present invention, there is provided a secondary battery pack having at least one secondary battery in a casing, and charging and discharging the secondary battery at a predetermined position on an outer surface of the casing. It has an external terminal, and in the middle of wiring for electrically connecting the secondary battery and the external terminal, it is attached to one of a device using a secondary battery pack as a power supply for operation, and a charger. Since there is a switch that becomes conductive as a condition, the clip between the external terminals for charging and / or the external terminals for discharging of the secondary battery pack when not attached to any device or charger Even if short-circuited by metal office supplies such as
The switch can prevent discharge of the secondary battery. Of course, in a state where there is no risk of being short-circuited by metal office supplies such as clips, that is, in a state where the secondary battery pack is attached to either the device or the charger, the switch is conductive. It is possible to perform discharging and charging without any inconvenience.

[0013]

Embodiments of the present invention will be described in detail below with reference to the accompanying drawings. FIG. 1 is an electric circuit diagram schematically showing the configuration of the secondary battery pack of the present invention. The secondary battery pack includes a secondary battery cell 21, charging terminals (external terminals) 31a and 32a, discharging terminals (external terminals) 31b and 32b, and a secondary battery cell 2
1, the protection circuit 5 connected between the + terminal and the + side charging terminal 32a and the + side discharging terminal 32b, and the − terminal and the − side charging terminal 31a and the discharging terminal 3 of the secondary battery cell 21.
1b and a short-circuit prevention switch (switch means) 6 connected between the switch 1b. The configurations of the secondary battery cell 21 and the protection circuit 5 are the same as the corresponding portions shown in FIG. Also, charging terminals 31a, 32a
The discharge terminals 31b and 32b are provided at predetermined positions on the surface of the casing, but the casing is not shown in FIG.

FIG. 2 is a diagram schematically showing an example of a configuration for operating the switch 6. As shown in FIG. As shown in FIG. 2, a normally open switch 6 that operates mechanically is provided inside the casing 1, and a recess 61 is provided in the casing 1 at a position facing the operating piece of the switch 6. A pressing member 62 for pressing the operating piece is provided at a place 61. Further, an urging spring 63 for urging the pressing member 62 in a direction in which the operating piece is not always pressed is provided. Then, the device or the charger in which the secondary battery pack is mounted enters the concave portion 61 at a predetermined position facing the concave portion 61 along with the mounting of the secondary battery pack, and urges the pressing member 62. A convex portion 64 that moves against the spring 63 is provided.

Examples of the casing 1 include those produced by injection molding using a thermoplastic resin such as polypropylene P, polyacetal, polystyrene, acrylonitrile butadiene styrene, and polycarbonate. The switch 6 may be a normally open type switch, and may be a good conductor such as copper, aluminum, iron, stainless steel, nickel, or an alloy thereof, or gold,
Examples thereof include those manufactured by punching and pressing, cutting, combinations thereof, and casting using a material plated with silver, copper, or the like.

The operation of the secondary battery pack having the above configuration is as follows. When the secondary battery pack is not attached to either the device or the charger, the pressing member 62 is moved by the biasing spring 63, so that the switch 6
Is not pressed, and the switch 6 remains open. Therefore, between the charging terminals 31a and 32a and / or
Alternatively, even if the discharge terminals 31b and 32b are short-circuited by metal office supplies such as clips, a closed circuit including the secondary battery cell 21 is not formed, and the secondary battery cell 2
The inconvenience that 1 is discharged can be reliably prevented. In addition, since this discharge prevention is performed mechanically, not electrically, even if the short circuit between the terminals continues for a long time or the short circuit is repeatedly performed, the above-mentioned disadvantages are avoided. Occurrence prevention is performed reliably, and safety can be guaranteed.

When the secondary battery pack is mounted on either the device or the charger, the convex portion 64 enters the concave portion 61 and moves the pressing member 62 against the biasing spring 63. Since the operating piece is pressed, the switch 6 is closed, and a closed circuit is formed between the device or the charger and the secondary battery cell 21, and the secondary battery cell 21 discharges or discharges the secondary battery cell 21. Charging can be performed.

FIG. 3 is a diagram schematically showing another example of the configuration for operating the switch 6. As shown in FIG. This configuration differs from the configuration of FIG. 2 only in that the pressing member 62 and the urging spring 63 are omitted, and the operating piece of the switch 6 is exposed in the recess 61. Therefore, when the configuration of this modified example is adopted, cost reduction can be achieved with simplification of the configuration, and the same operation as the configuration example of FIG. 2 can be achieved.

In the embodiment of the present invention, if a casing 1 having excellent watertightness is adopted, even if the secondary battery pack is immersed in water, the secondary battery cells 21
Can reliably be prevented from being discharged. In the embodiment of the present invention, two or more secondary battery packs are used,
In addition to being able to be connected to each other in series and / or to be connected in parallel, various design changes can be made without departing from the scope of the present invention.

[0020]

According to the first aspect of the present invention, a clip or the like is provided between the external terminals for charging and / or the external terminals for discharging of the secondary battery pack in a state where the external terminals are not attached to any of the equipment and the charger. The switch can prevent the discharge of the secondary battery even if it is short-circuited by metal office supplies, etc., and even if the short-circuit between the terminals continues for a long time, the short-circuit repeatedly occurs. Even if it does, there is a unique effect that the discharge of the secondary battery can be reliably prevented and higher safety can be guaranteed.

[Brief description of the drawings]

FIG. 1 is an electric circuit diagram schematically showing a configuration of a secondary battery pack of the present invention.

FIG. 2 is a diagram schematically illustrating an example of a configuration for operating a switch.

FIG. 3 is a diagram schematically showing another example of a configuration for operating a switch.

FIG. 4 is a diagram showing in detail an internal configuration of a conventional secondary battery pack.

FIG. 5 is an electric circuit diagram schematically showing a configuration of a conventional secondary battery pack.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Casing 6 Switch 21 Secondary battery cell 31a, 32a Charging terminal 31b, 32b Discharging terminal

Claims (1)

[Claims] 1. A casing (1) having at least one secondary battery (21) in a casing (1), and charging and discharging the secondary battery (21) at a predetermined position on an outer surface of the casing (1). Terminals (31a) (31b) (32a) for
(32b), wherein the secondary battery (21) and the external terminals (31a) (31)
b) A switch that is in a conductive state on the condition that it is attached to one of a device or a charger that uses a secondary battery pack as an operating power supply, in the middle of a wiring for electrically connecting (32a) and (32b). 6) A secondary battery pack comprising: