JP5048366B2 - Protective device - Google Patents

Description

  The present invention relates to a protection device for an electronic device having a rechargeable secondary battery, and more particularly to a protection device that automatically stops power supply to an electronic device due to expansion of the secondary battery.

  At present, mobile phones, portable audio devices, mobile personal computers, PDAs, and other portable electronic devices are widely used. In particular, mobile phones have become indispensable for people's lives. As a power supply source for such portable electronic devices, secondary batteries that can be charged from an external power source, a power generation device, or the like are generally used. The secondary battery is also used as a power source for a mobile device such as an electric vehicle.

  However, in recent years, there has been a problem that secondary batteries used in such electronic devices expand due to some cause such as an abnormal increase in internal pressure.

  The expanded secondary battery has a case where power is continuously supplied to an electronic device as usual and a case where abnormality occurs in the supply of power. In particular, when the package of the secondary battery is made of a soft material such as a resin or a laminate, there is a case where the expansion of the secondary battery is restored for some reason and can be used as usual.

  When an abnormality occurs in the power supply due to the expansion of the secondary battery, the protection device that detects this output abnormality performs a predetermined treatment, so that the user can recognize the abnormality of the electronic device. However, in the case where power supply abnormality does not occur in the expanded secondary battery, the protection device does not operate and the expanded secondary battery continues to supply power to the electronic device. In this case, since the electronic device operates normally, the user cannot know the abnormality of the electronic device. Such continuous power supply by the expanded secondary battery is not preferable even if there is no abnormality in the supplied power.

  Furthermore, depending on the cause of the expansion of the secondary battery, it may expand further by continuing to supply power to the electronic device, and may eventually rupture, causing serious damage to the electronic device, or sudden abnormal discharge. There is no denying the possibility of damage to the circuit. In addition, the physical force generated by the expansion of the secondary battery may cause distortion or cracks in the packaging of electronic devices and the electronic components and members that make up the electronic devices, and the electronic devices include switches and motors. If this is the case, an abnormal load may be applied to them, causing malfunction or failure. In addition, some batteries may generate heat depending on the cause of expansion. In particular, in the case where the secondary battery has a large scale and large capacity, the secondary battery itself or the secondary battery may be caused by heat generation related to expansion of the secondary battery. In the worst case, it is also assumed that structural members and the like around the user may cause a human damage to the user due to ignition or explosion.

  In the inventions disclosed in the following [Patent Document 1] and [Patent Document 2] with respect to the above-mentioned problems, both of the secondary batteries are improved by improving main members related to charging and discharging of the secondary battery. The occurrence of expansion is prevented.

JP 2006-339011 A

JP 2006-269234 A

  However, in addition to the cause of secondary battery expansion, the secondary battery expansion is caused by complex intertwining of the usage environment, usage conditions, and other factors of electronic equipment, which has yet to be elucidated. There are many parts, and even the invention disclosed in [Patent Document 1] and [Patent Document 2] cannot completely prevent the secondary battery from expanding. Moreover, it takes much time to identify the cause of occurrence of all secondary batteries and to develop a secondary battery that avoids them.

  The present invention has been made in view of the above circumstances, and automatically stops power supply to the electronic circuit when the outer shape of the secondary battery expands, and automatically returns to the electronic circuit when the outer shape of the secondary battery is restored. An object of the present invention is to provide a protection device that can detect continuous expansion of a secondary battery at an early stage by restarting power supply.

The present invention is installed in an electronic device 10 that is operated by power supply from a secondary battery 16, and automatically stops power supply to the electronic device 10 as the secondary battery 16 expands in outer shape. in automatically resume protection device power supply 16 to the electronic device 10 with the restoration of the outer shape of the first electrode 20 provided on the side surface side of the secondary battery 16, opposite to the first electrode 20 a second electrode 22 provided so as to have, by a non-contact state or contact state by the expansion or restoration of the outer shape of the secondary battery 16, electrically stopped or the power supply to the electronic device 10 By providing the protection devices 50a, 50b, and 50c described above, which are restarted, the above-described problems are solved.
In addition, the protection devices 50d, 50e, and 50f are provided, which are provided with the elastic body 24 that generates a restoring force in the installation direction of the first electrode 20 and the second electrode 22 when the secondary battery 16 expands. This solves the above problem.
Also, by providing the protective device 50, wherein fixing the first electrode 20 to the side of the secondary battery 16, to solve the above problems.

The protection device according to the present invention has the above-described configuration.
(1) When the outer shape of the secondary battery expands, the power supply to the electronic device is automatically stopped regardless of whether there is an abnormality in the power supply. Therefore, the user may detect an abnormality and take appropriate measures at an early stage. it can.
(2) Since the power supply to the electronic device is automatically resumed when the secondary battery's external shape is restored, excessive treatment should be avoided when the secondary battery expands in a short-term and non-continuous manner with relatively little problem. Thus, the electronic device can be used as it is.

Embodiments of a protection device according to the present invention will be described with reference to the drawings. FIG. 1 is a schematic view when the protection device according to the present invention is applied to a portable precharger. FIG. 2 is a partially enlarged view showing a first embodiment of the protection device according to the present invention. FIG. 3 is a partially enlarged view showing a second embodiment of the protection device according to the present invention . Incidentally, since here described embodiment is a preferred embodiment of the present invention, that various technically preferable limitations are imposed, the scope of the present invention is to limit the particular invention in the following description Unless otherwise described, the present invention is not limited to these embodiments.

  An electronic device 10 that is a portable precharger for a mobile phone shown in FIG. 1 includes a secondary battery 16 and a circuit board 18 inside an exterior body 12, and the circuit board 18 includes a secondary battery 16. And an electronic circuit such as a protection circuit against overcharge, overheat, overcurrent, overdischarge, and short circuit, and a control circuit for controlling the operation of the electronic device 10. The secondary battery 16 and the circuit board 18 are fixed to the exterior body 12, and a protection device 50 according to the present invention is provided between the exterior body 12 and the secondary battery 16. The protective device 50 is preferably installed on the side surface of the secondary battery 16 on the side without the circuit board 18 (the surface opposite to the circuit board 18 or the side surface adjacent thereto). If measures are taken so as not to affect the operation of the board 18, the circuit board 18 may be installed. Moreover, the protection device 50 does not necessarily need to be singular, and can be installed on each of a plurality of side surfaces of the secondary battery 16. In addition, when the secondary battery 16 is stored and used in a battery storage unit or the like, the battery storage unit becomes the exterior body 12. Further, when the secondary battery 16 is disposed adjacent to any fixed device, substrate, member, etc., the surface of the adjacent device, substrate, member, etc. on the secondary battery 16 side is the exterior body 12. The protective device 50 may be provided between them.

  The type of the secondary battery 16 used in the electronic device 10 is not particularly limited, and a known secondary battery can be used in addition to a lithium ion battery, a nickel cadmium battery, a nickel hydrogen battery, and the like.

  Next, an outline of the operation of the electronic device 10 which is a portable precharger will be described. First, when the secondary battery 16 constituting the electronic device 10 is charged, the secondary battery 16 and the power supply source 5 are connected to the circuit. The connection is made through the substrate 18. As a result, the secondary battery 16 is charged with power from the power supply source 5.

  Examples of the power supply source 5 include a household outlet, a charger of a mobile phone 6 connected to the household outlet or an AC-DC conversion adapter, a vehicle battery via a cigar socket, and a solar panel that generates power by light irradiation. Etc. can be used.

  Next, when charging the secondary battery in the mobile phone 6 using the electronic device 10 that is a portable precharger, the secondary battery 16 and the mobile phone 6 are connected via the circuit board 18. Thereby, the electric power stored in the secondary battery 16 is output, and the secondary battery of the mobile phone 6 is charged.

  Next, the operation of the protection device 50 according to the present invention will be described. The protection device 50 does not perform any special operation when the secondary battery 16 is in a normal state, and thus the electronic device 10 operates normally. However, as shown by the broken line in FIG. 1, when the outer shape of the secondary battery 16 expands for some reason, the protection device 50 detects the expansion and performs a predetermined operation such as opening the switching mechanism 51, for example. The power supply to the electronic device 10 is automatically stopped. Thereby, operation | movement of the electronic device 10 including charging / discharging operation | movement with respect to the secondary battery 16 stops. This stopping operation continues while the outer shape of the secondary battery 16 is expanded.

  Further, when the external shape of the secondary battery 16 is restored due to some cause such as internal gas release, the protection device 50 performs a predetermined operation such as closing the switching mechanism 51, and the electronic device 10 from the secondary battery 16. Restart the power supply to. Thereby, the electronic device 10 starts the normal operation.

  As the switching mechanism 51, a well-known mechanism such as a switching IC with an auto reset function, a switching transistor, a switching circuit having other circuit configuration, a switch, or the like can be appropriately selected depending on the configuration of the protection device 50. . Further, the switching mechanism 51 is not necessarily provided on the circuit board 18, and the protection device 50 may also have the switching mechanism 51 as described later.

Next, the 1st form of the protection apparatus which concerns on this invention is demonstrated using the partial enlarged view of FIG. In FIG. 2 and FIG. 3 shown below, description of electric wiring in the protection device 50 is omitted.

  A protection device 50a according to the first embodiment of the present invention shown in FIGS. 2 (a1) and 2 (a2) includes a first electrode 20 provided on the side of the secondary battery 16 and a first electrode on the exterior body 12 side. 20 has a second electrode 22 provided to face 20 and a switching mechanism (not shown). The first electrode 20 and the second electrode 22 are installed with a predetermined distance (preferably about 1 mm).

  First, when the secondary battery 16 does not expand, the first electrode 20 and the second electrode 22 are not in contact with each other, as shown in FIG. In such a case, the protective device 50a does not perform any special operation, and the electronic device 10 operates normally. However, as shown in FIG. 2 (a2), when the outer shape of the secondary battery 16 expands, the first electrode 20 provided on the side surface of the secondary battery 16 has an exterior body due to the expansion of the secondary battery 16. It is pushed up in the direction of the second electrode 22 provided on the 12 side. When the expansion of the secondary battery 16 increases to exceed the gap distance between the first electrode 20 and the second electrode 22, the first electrode 20 and the second electrode 22 come into contact with each other. The first electrode 20 and the second electrode 22 are provided with electrical wiring (not shown), and the first electrode 20 and the second electrode 22 are electrically connected by this contact. In addition, a switching mechanism (not shown) is connected to the tip of the electrical wiring of the first electrode 20 and the second electrode 22, and this switching mechanism receives the conduction between the first electrode 20 and the second electrode 22, so that the secondary electrode The power supply from the battery 16 to the electronic device 10 is stopped. Thereby, the operation of the electronic device 10 is stopped.

  When the outer shape of the secondary battery 16 is restored, the first electrode 20 and the second electrode 22 are brought into a non-contact state again as shown in FIG. Connection with is interrupted. When the conduction between the first electrode 20 and the second electrode 22 is interrupted, a switching mechanism (not shown) resumes power supply from the secondary battery 16 to the electronic device 10, whereby the electronic device 10 operates normally. .

  With the above operation, the protection device 50a can stop the power supply to the electronic device 10 when the outer shape of the secondary battery 16 expands, and can restart the power supply to the electronic device 10 when the outer shape of the secondary battery 16 is restored. it can.

  Next, the 1st modification of the 1st form of the protection device concerning the present invention is shown in Drawing 2 (b1) and (b2). A protection device 50b, which is a first modification of the first form of the protection device, includes a convex first electrode 20 having conductivity only at a tip portion provided on the side surface side of the secondary battery 16, and the exterior body 12. A cylindrical or U-shaped second electrode 22 having a conductive recess only at the tip provided on the side, and a switching mechanism (not shown) connected to the first electrode 20 and the second electrode 22. Have. The first electrode 20 and the second electrode 22 are disposed to face each other so that the convex portion of the first electrode 20 can move in the concave portion of the second electrode 22.

  First, when the outer shape of the secondary battery 16 is not expanded, as shown in FIG. 2 (b1), the leading end portion of the first electrode 20 and the leading end portion of the concave portion of the second electrode 22 both have conductivity. The first electrode 20 and the second electrode 22 are in electrical contact with each other.

  However, when the outer shape of the secondary battery 16 expands, the front end portion of the conductive first electrode 20 is located on the back side of the recess of the second electrode 22 that exhibits insulation due to the expansion of the secondary battery 16 (FIG. 2). It is pushed up in the direction of (b1) and (b2). As a result, as shown in FIG. 2 (b2), the first electrode 20 and the second electrode 22 are not in contact with each other, and the conduction between the first electrode 20 and the second electrode 22 is interrupted.

  Further, when the outer shape of the secondary battery 16 is restored, as shown in FIG. 2 (b1), the first electrode 20 and the second electrode 22 are brought into contact again, and the first electrode 20 and the second electrode 22 are in contact with each other. Conduct.

  A switching mechanism (not shown) is connected to the first electrode 20 and the second electrode 22, and this switching mechanism interrupts conduction between the first electrode 20 and the second electrode 22, contrary to the case of the protective device 50 a. In such a case, the power supply to the electronic device 10 is stopped.

  As a result, the protection device 50b stops the power supply to the electronic device 10 when the outer shape of the secondary battery 16 expands, and the power supply to the electronic device 10 when the outer shape of the secondary battery 16 is restored, like the protection device 50a. It can be resumed.

  If the second electrode 22 is installed so as to be embedded in the exterior body 12, the second electrode 22 is not damaged by the expansion of the secondary battery 16.

  Next, the 2nd modification of the 1st form of the protection device concerning the present invention is shown in Drawing 2 (c1) and (c2). In a protection device 50c, which is a second modification of the first form of protection device, the first electrode 20 is provided on the secondary battery 16 at a predetermined distance from the center of the secondary battery 16. In addition, a rod-like or plate-like second electrode 22 having a predetermined length has one end opposed to and in contact with the first electrode 20 and is fixed to the secondary battery 16 only at the other end. A switching mechanism (not shown) is connected to the first electrode 20 and the second electrode 22.

  First, when the outer shape of the secondary battery 16 is not expanded, as shown in FIG. 2C1, the first electrode 20 and the second electrode 22 are in contact with each other, and the first electrode 20 and the second electrode 22 is electrically connected.

  However, when the outer shape of the secondary battery 16 expands, one end of the second electrode 22 on the first electrode 20 side is lifted by the expansion of the secondary battery 16 as shown in FIG. And the second electrode 22 are not in contact with each other. Thereby, conduction between the first electrode 20 and the second electrode 22 is interrupted.

  Furthermore, when the outer shape of the secondary battery 16 is restored, as shown in FIG. 2C1, the first electrode 20 and the second electrode 22 are brought into contact again, and the first electrode 20 and the second electrode 22 are in contact with each other. Conduct.

  The switching mechanism connected to the first electrode 20 and the second electrode 22 is the same as that of the protection device 50b depending on the contact between the first electrode 20 and the second electrode 22, the electrical continuity associated with the non-contact state, and the interruption. Perform the operation.

  Thereby, the protective device 50c can stop the power supply to the electronic device 10 when the outer shape of the secondary battery 16 expands, and can restart the power supply to the electronic device 10 when the outer shape of the secondary battery 16 is restored.

  In the protective devices 50b, 50c and the protective device 50f described later, the first electrode 20 and the second electrode 22 are in a conductive state when the secondary battery 16 is not expanded, and the outer shape of the secondary battery 16 is expanded. Since the first electrode 20 and the second electrode 22 are sometimes cut off, the circuit configuration of the switching mechanism can be further simplified. Further, if the protection devices 50b, 50c, and 50f are provided on the power supply path from the secondary battery 16, the protection devices 50b, 50c, and 50f can also serve as a switching mechanism.

  Next, a second embodiment of the protection device according to the present invention will be described with reference to a partially enlarged view of FIG.

  A protection device 50d according to the second embodiment of the present invention shown in FIGS. 3A1 and 3A2 includes a first electrode 20 provided on the side surface of the secondary battery 16 and a first electrode on the exterior body 12 side. 20, a second electrode 22 provided so as to face 20, an elastic body 24 provided between the first electrode 20 and the second electrode 22, and a switching mechanism (not shown). The first electrode 20 and the second electrode 22 are held by the elastic body 24 so as to have a predetermined interval.

  In the protective device 50d, the elastic body 24 is illustrated as a leaf spring, the protective device 50e described later is illustrated as a spring, and the protective device 50e is illustrated as a cylindrical rubber. However, the elastic body 24 used is not particularly limited and is made of metal. It is possible to use a spring made of resin, a leaf spring, a bow spring, a wire spring, a torsion spring, etc., an elastic member having elasticity such as rubber, a cylinder, a rectangular parallelepiped, or the like. In the case where a conductive member such as a metal is used for the elastic body 24, at least contact of the first electrode 20 or the second electrode 22 so that the first electrode 20 and the second electrode 22 are not always in a conductive state. The part must be made insulating by inserting an insulating film or insulator.

  In the protection device 50d, when the outer shape of the secondary battery 16 is not expanded, the first electrode 20 and the second electrode 22 are in a non-contact state as shown in FIG. However, when the secondary battery 16 expands, the first electrode 20 is pushed up in the direction of the second electrode 22 by the expansion of the secondary battery 16, and as shown in FIG. And the second electrode 22 are in contact with each other. Thereby, the first electrode 20 and the second electrode 22 are electrically connected. Further, when the outer shape of the secondary battery 16 is restored, as shown in FIG. 3A1, the first electrode 20 and the second electrode 22 are brought into a non-contact state again, and the first electrode 20 and the second electrode 22 are restored. Connection with is interrupted.

  And the switching mechanism connected to the 1st electrode 20 and the 2nd electrode 22 is based on the contact with this 1st electrode 20 and the 2nd electrode 22, the electrical continuity in connection with a non-contact state, and interception, protection device 50a. The same operation is performed. Thereby, the protection device 50d can stop the power supply to the electronic device 10 when the outer shape of the secondary battery 16 expands, and can restart the power supply to the electronic device 10 when the outer shape of the secondary battery 16 is restored.

  The protective device 50d may be provided with an elastic body 24 at the central portion between the first electrode 20 and the second electrode 22 as in the protective device 50e shown in FIGS. 3 (b1) and 3 (b2).

  Next, the modification of the 2nd form of the protection apparatus which concerns on this invention is shown to FIG.3 (c1), (c2). The protective device 50f shown in FIGS. 3C1 and 3C2 is provided on the secondary battery 16 side, and one end of the protective device 50f is separated from the center of the secondary battery 16 by a predetermined distance and bent toward the exterior body 12 side. The first electrode 20 having a length, the second electrode 22 having a predetermined length provided on the exterior body 12 side, the other end of the first electrode 20 located at the approximate center of the secondary battery 16, and the second electrode The elastic body 24 provided so that it may be pinched | interposed with 22, the insulating protrusion 26 provided in the part located in the approximate center of the 2nd electrode 22, and the switching mechanism which is not shown in figure. The bent end of the first electrode 20 and one end of the second electrode 22 are in contact with each other by the elastic body 24, and the first electrode 20 and the second electrode 22 are held.

  First, when the external shape of the secondary battery 16 is not expanded, the first electrode 20 and the second electrode 22 are in contact with each other as shown in FIG. However, when the secondary battery 16 expands, the elastic body 24 side of the first electrode 20 is pushed up toward the second electrode 22 and the bent end of the first electrode 20 protrudes as shown in FIG. The object 26 moves to the secondary battery 16 side as a fulcrum. Thereby, the 1st electrode 20 and the 2nd electrode 22 will be in a non-contact state. Further, when the outer shape of the secondary battery 16 is restored, as shown in FIG. 3C1, the first electrode 20 and the second electrode 22 are brought into contact again.

  And the switching mechanism connected to the 1st electrode 20 and the 2nd electrode 22 is based on the contact with this 1st electrode 20 and the 2nd electrode 22, the electrical conduction according to a non-contact state, and interception, protection device 50b. The same operation is performed. Thereby, the protection device 50f can stop the power supply to the electronic device 10 when the outer shape of the secondary battery 16 expands, and can restart the power supply to the electronic device 10 when the outer shape of the secondary battery 16 is restored.

  In the protection devices 50d, 50e, and 50f, when the secondary battery 16 expands in shape, a restoring force is generated in the elastic body 24 in the installation direction of the first electrode and the second electrode. Therefore, when the outer shape of the secondary battery 16 is restored, the first electrode 20 and the second electrode 22 can be quickly returned to the positions before expansion by the restoring force of the elastic body 24. Further, the presence of the elastic body 24 can prevent malfunction of the protective device due to vibration or the like.

Since on the following, the protection device according to the present invention has the outer shape of the secondary battery expands, automatically stops the power supply to the electronic device irrespective of the presence or absence of an abnormality in the power supply from the secondary battery. Therefore, the user can detect an abnormality and take appropriate measures such as repair or evacuation at an early stage. Furthermore, depending on the cause of the expansion of the secondary battery, it is possible to prevent the secondary battery from bursting or damaging the electronic circuit.

  Further, the protection device according to the present invention automatically restarts the power supply to the electronic circuit when the external shape of the secondary battery is restored. For this reason, when the secondary battery expands in a short-term and non-continuous manner with relatively few problems, it is possible to avoid excessive treatment such as unnecessary repair and continue to use the electronic device as it is. However, when the expansion of the secondary battery in the short term frequently occurs, the electronic device is also frequently stopped, so that the user can detect an abnormality and take appropriate measures.

In addition, each member used for the first electrode 20 and the second electrode 22 of the protection device may be directly fixed to the secondary battery 16 or the exterior body 12 with an adhesive tape, an adhesive, etc. You may install through a plate-shaped member. However, in the protection devices 50a and 50c, the plate-like member to be used is preferably a flexible member that can be easily bent. In addition, the signals exchanged between the members used for the first electrode 20 and the second electrode 22 of the protective device and the switching mechanism include a DC signal, an AC signal, a pulse signal having a predetermined frequency, and the like. Can be used.

  In this example, the description has been given by taking the portable precharger of the cellular phone as an example of the electronic device. However, the present invention is not particularly limited to this, and the cellular phone including the secondary battery and the mobile personal computer are not limited thereto. , PDAs, portable MD players, portable CD players, portable DVD players, portable audio equipment with a hard disk or nonvolatile memory, portable chargers other than mobile phones, other electronic devices, and electric vehicles (hybrids) The present invention can be applied to an electronic device for controlling a secondary battery as a power source of a mobile device such as a car), and the present invention is modified and implemented without departing from the gist of the present invention. It is possible.

It is the schematic at the time of applying the protection apparatus which concerns on this invention to a portable precharger. It is the elements on larger scale which show the 1st form of the protection apparatus which concerns on this invention. Ru partially enlarged view showing a second embodiment of the protection device according to the present invention.

10 Electronic equipment
16 Secondary battery
20 First electrode
22 Second electrode
24 Elastic body
28 Switch
50, 50a- 50f protection device

Claims (3)

Installed in electronic equipment that operates by supplying power from secondary batteries,
While automatically stopping the power supply to the electronic device with the expansion of the secondary battery,
In the protective device that automatically restarts the power supply to the electronic device with the restoration of the external shape of the secondary battery ,
A first electrode provided on a side surface of the secondary battery;
A second electrode provided to face the first electrode,
By becoming a non-contact state or a contact state by expansion or restoration of the outer shape of the secondary battery,
A protective device characterized by electrically stopping or resuming power supply to the electronic device. First electrode and protective device according to claim 1, characterized in that an elastic body produced a restoring force in the installation direction of the second electrode during contour expansion of secondary batteries. Protection device according to claim 1 or claim 2, wherein the fixing the first electrode to the side of the secondary battery.

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