JPH07335274A - Object deformation detecting sensor and storage battery with current path disconnecting function additionally provided with this object deformation detecting sensor - Google Patents

Abstract

PURPOSE:To provide a storage battery with a current path disconnecting function, disconnecting a current path simultaneously with detecting deformation, by providing an object deformation detecting sensor of simple structure. CONSTITUTION:A storage battery has a storage means 55 having a metal casing 40 to draw out electric energy in the inside to the outside through the first/ second terminals (40, 41) and an insulating substrate 44 having an electrode in both sides of this storage means. The one electrode of the insulating substrate 44 is connected to the first terminal of the storage means 55, to use the second terminal of the storage means 55 and the other electrode of the insulating substrate 44 as a take out electrode of this storage battery. Further, the insulating substrate 44 is arranged into contact with the metal casing 40 and formed of material of low toughness which can be destructed by receiving deformation stress of the metal casing 40, and a conductive pattern of low toughness is formed on the insulating substrate 44.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an article deformation detection sensor for detecting the deformation of an article, and particularly the deformation of a rechargeable Li-ion secondary battery used in a mobile phone or the like due to the gas pressure inside the cell. The present invention relates to a storage battery with a current path breaking function, which is provided with a deformation detection sensor for the article.

[0002]

2. Description of the Related Art Conventionally, a sensor for detecting a displacement of an article is known as a sensor for detecting a deformation of an article. In that case, a pressure sensor is fixed to the article and the output of the pressure sensor is detected. It is known that the displacement amount is detected by the method. Moreover, in Li (lithium) ion secondary batteries and the like, when the storage battery is overcharged or over-discharged, the gas pressure inside the battery rises and the storage battery explodes. It has been proposed to provide a safety valve for exhausting the gas in the battery when the pressure reaches. Here, the Li-ion secondary battery will be described. The operating principle is that the electrons are sent to the carbonaceous material of the negative electrode during charging and are occluded in the positive electrode.
The i ions are desorbed and occluded in the negative electrode, resulting in a potential difference.
On the contrary, at the time of discharge, Li stored in the carbon material of the negative electrode
Ions are desorbed and occluded in the positive electrode, sending out electrons and causing a current to flow in an external circuit. The inside of the Li-ion secondary battery is
It has a spiral structure in which a sheet-shaped positive electrode and a negative electrode are spirally wound with a polyolefin-based separator interposed therebetween. A composite metal oxide composed of Li ions and a specific metal was used as an active material for the positive electrode, and a specific carbonaceous material was used for the negative electrode. Positive electrode,
Both the negative electrode contains Li in an ionic state and has low reactivity with air and moisture. Therefore, the Li-ion secondary battery can be manufactured in a normal atmosphere. An aprotic organic solvent in which a Li salt is dissolved is used as the electrolytic solution. High ionic conductivity and stable voltage. The Li ion concentration in the electrolytic solution does not change during charging and discharging. Further, the safety valve is mounted to exhaust gas when an abnormality occurs in the battery and the internal pressure rises.

[0003]

However, in the prior art, the structure of the pressure sensor is complicated, and the mounting work thereof is troublesome. In addition, it is not preferable to reuse the storage battery in which the internal pressure has risen due to an abnormality. However, in the related art, when the pressure reaches a predetermined value by the safety valve, the gas in the battery is only exhausted, and thus the storage battery may be used again by mistake.

A first object of the present invention is to provide a deformation detection sensor for an article having a simple structure. A second object of the present invention is to provide a storage battery with a current path interruption function that detects a deformation and at the same time interrupts the current path.

[0005]

A first object of the present invention is to provide a base material having low toughness that can be destroyed by deformation stress of an article, a conductive pattern having low toughness formed on the base material, and the conductive pattern. It is achieved by the first means having an electrode connected to the substrate and arranged so as to sandwich at least the broken portion of the base material. The above-mentioned first object is achieved by the second means according to the first means, wherein the conductive pattern is formed in a loop shape that passes through the breaking portion of the base material a plurality of times. The first object can be achieved by the third means in which the conductive pattern is provided on the surface of the base material opposite to the surface facing the article side in the first means. The first object is, in the first means, forming a V groove extending in a direction perpendicular to a line connecting the electrodes of the base material,
This is achieved by the fourth means in which the conductive pattern is formed on the V groove forming surface. The first object is to provide a flexible base material, a conductive pattern having low toughness which is formed on the flexible base material and can be broken by receiving a deformation stress of an article, and which is connected to the conductive pattern. This is achieved by a fifth means having electrodes arranged so as to sandwich the breaking portion of the flexible base material.

The second object is achieved by the sixth means using the deformation detecting sensor of the first means as a current path of the power storage means. The second object is to have a power storage means having a housing and a conductive means, the conductive means being connected to a part of a current path of the power storage means, being arranged in contact with the housing, The means is achieved by the seventh means formed of a material having low toughness that can be destroyed by the deformation stress of the housing. The second object is achieved by the eighth means in the seventh means, wherein the conductive means is a substrate having low toughness and a conductive pattern having low toughness. The second object is the seventh means, wherein the conductive means is
This is achieved by the ninth means which is a conductive pattern having low toughness formed directly on the electricity storage means. The second object is to have a power storage means that has a housing and leads out internal electric energy to the outside through first and second terminals, and conductive means having electrodes at both ends thereof. One of the electrodes is connected to the first terminal of the power storage means, the second terminal of the power storage means and the other electrode of the conductive means serve as a take-out electrode of the storage battery, and the conductive means is the housing. And the conductive means is formed by a tenth means formed of a material having low toughness capable of being broken by receiving the deformation stress of the housing. The above second object is achieved by the eleventh means for holding and fixing a ceramic substrate by the substrate holding means extending from the housing of the electricity storage means in the tenth means. The second object is one of the destructive sensor, a destructive sensor having a pair of electrodes, a destructive sensor mounted on the destructive means and having a pair of terminals, a holding member for holding the detection sensor, and the destructive sensor. This is achieved by a twelfth means having a take-out electrode connected to the terminal of No. 1 and a conductive means connecting between the other terminal of the destruction sensor and one electrode of the electric storage means.

[0007]

In the first means, the deformation of the article can be detected with a simple structure. In the second means, one of the loop-shaped conductive patterns that pass a plurality of times is used.
Since it is sufficient that the book breaks at least, it is possible to increase the reliability of interruption. In the third means, when the base material expands and deforms, when the base material cracks, the base material moves in the direction away from the case where the conductive pattern is provided on the lower surface, so that the conductive pattern is reliably blocked. You can In the case of the fourth means, when the base material is broken, the conductive pattern is surely cut off. In the fifth means, since the conductive pattern can be cut without breaking the substrate, the conductive pattern can be broken with a small pressure. In the sixth to eleventh means, the current path can be interrupted at the same time as the deformation of the storage battery is detected.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 6 are for explaining a first embodiment of the present invention. FIG. 1 is an exploded perspective view of the first embodiment, FIG. 2 is a sectional view of the first embodiment, and FIG. Circuit diagram of the first embodiment,
4 is an explanatory view showing a cracked state of the ceramic substrate of the first embodiment, FIG. 5 is a perspective view showing a modified example 1 of the ceramic substrate of the first embodiment, and FIGS. 6 (a) and 6 (b) are It is a perspective view which shows the modifications 2 and 3 of the ceramic substrate of a 1st Example.

In these figures, 8 is a battery, and
Is the Li-ion secondary battery described above.
~ 3 electrodes 5, 6, 7 are provided. An electromotive force E is generated between the second electrode 6 and the third electrode 7. Reference numeral 1 is a substrate having a low toughness such as a ceramic substrate, and a conductive pattern 2 is formed on the surface of the ceramic substrate 1 by printing. The conductive pattern 2 is a composite type conductive pattern containing silver using a thermoplastic resin as a binder and has low toughness. On the lower side of the ceramic substrate 1, a V-shaped groove 3 is formed over the entire width of the substrate 1. The conductive pattern 2 may be of a composite type in which metal powder such as ruthenium oxide is mixed with glass as a binder.

Reference numeral 4 denotes a terminal made of a metal material of phosphor bronze plated with Ag. The terminal 4 is elastically contacted with the first leg 4a, 4b having a bifurcated shape which elastically contacts the conductive pattern 2 and the lower surface of the battery 8. The second leg 4c and the first electrode 5 or 7 of the battery 8
Is provided and a cut-and-raised portion 4d that fits with the electrode 5 or 7 is provided, and has a substantially U shape as a whole. With these terminals 4 and 4, as shown in FIG.
The ceramic substrate 1 placed on the battery 8 is clamped. The second leg 4c may not be provided.

Next, the operation of the first embodiment will be described. Usually, this unit is incorporated in an electric appliance (not shown), and the second electrode 6 and the first electrode 5 of the battery 8 are used as power supply terminals of the electric appliance (not shown). Here, as described above, the battery 8 is overcharged or overdischarged.
When the internal pressure rises and the storage battery deforms, the ceramic substrate 1 is cracked and at the same time the conductive pattern 2 is formed, as shown in FIG.
Also breaks. A indicates an expanded portion of the battery 8. This allows
Since the circuit shown in FIG. 3 is disconnected, overcharge or overdischarge of the storage battery is stopped. Therefore, the storage battery does not further expand and burst.

A modification of the ceramic substrate 1 of the first embodiment will be described with reference to FIGS. 5 and 6. In the modified example 1 of the ceramic substrate 1, as shown in FIG. 5, both side surfaces thereof are notched so that the notch portions 10 and 10 reach the conductive pattern 2.
Further, in the second modification of the ceramic substrate 1, as shown in FIG. 6A, the groove 11 is provided on the conductive pattern forming surface side, and the groove 11 is not provided only near the end face. A conductive pattern 21 is provided across the. Further, in the third modification of the ceramic substrate 1, as shown in FIG. 6B, the groove 12 is provided over the entire width on the conductive pattern forming surface side, and the conductive pattern 22 simultaneously crosses the groove 12 a plurality of times in a loop shape. There is. This groove 12
Grooves 13 are also provided on the lower surface of the ceramic substrate 1 so as to face each other over the entire width.

The shape of the fractured portion formed on the ceramic substrate 1 may be a chain line shape having a through hole, and in the case of this shape or the shape of FIG. 6A, the strength of the ceramic substrate 1 is increased. Can be secured as needed.

In the first embodiment thus constructed, the ceramic substrate 1 having a low toughness which can be destroyed by the deformation stress of the battery 8 and the conductive material having a low toughness formed on the ceramic substrate 1. Since it has the pattern 2 and the electrodes 6 and 7 which are connected to the conductive pattern 2 and are arranged so as to sandwich at least the destroyed portion of the ceramic substrate 1, it is possible to provide a deformation detection sensor for an article having a simple structure. In addition, in the first embodiment, the conductive pattern 22 is formed in a loop shape that passes through the groove 12 which is the breaking portion of the ceramic substrate 1 a plurality of times. Therefore, it is sufficient that at least one of them breaks. The reliability of can be increased. Further, in the first embodiment, the conductive pattern 2 is formed on the surface of the ceramic substrate 1 opposite to the surface facing the electricity storage means (8) side.
Therefore, when the substrate 1 expands and deforms, if the substrate 1 breaks, the conductive pattern 2 can be moved away from the lower surface as compared with the case where the conductive pattern 2 is provided on the lower surface, so that the conductive pattern 2 can be reliably blocked. The overcharge or overdischarge of the storage battery does not stop, and the storage battery does not expand and burst. In the first embodiment, the groove 3 extending in the direction perpendicular to the line connecting the electrodes 6 and 7 of the ceramic substrate 1 is formed,
Since the conductive pattern 2 is formed on the surface where the groove 3 is formed, when the ceramic substrate 1 is broken, the conductive pattern 2 is surely cut off.

Next, a second embodiment of the present invention will be described with reference to FIG. FIG. 7 is a front view of the second embodiment. In the second embodiment, the difference from the first embodiment is that the conductive pattern 25 is directly formed on the electricity storage means (8) and at the same time, the conductive pattern 25 is extended to the electrodes 5 and 7 of the electricity storage means (8). It is extended and the other parts are the same as those in the first embodiment. In the second embodiment, the conductive pattern 25 can be made of an epoxy-based conductive adhesive or the like.

Next, a third embodiment of the present invention will be described with reference to FIG. FIG. 8 is a perspective view of the substrate of the third embodiment. The third embodiment differs from the first embodiment only in the insulating substrate and the conductive pattern, and the other parts are the same. As shown in FIG. 8, the insulating substrate 30 is a flexible film such as pet and polyimide, and the conductive pattern 31 formed on the insulating substrate 30 is an ITO film. In the third embodiment, since the conductive pattern 31 can be cut by bending the insulating substrate 30 without breaking the insulating substrate 30, the conductive pattern 31 can be broken with a small pressure.

Next, a fourth embodiment of the present invention will be described with reference to FIGS. 9 and 10. FIG. 9 is an exploded perspective view of the fourth embodiment, and FIG. 10 is an enlarged explanatory view of main parts of the fourth embodiment.
The fourth embodiment is an example in which a storage battery of a type different from the storage battery described above is formed. That is, in the fourth embodiment, the negative electrode is taken out from the metal casing 40 (the casing 40 is a negative electrode), and the positive electrode is taken out from the electrode 41 protruding from the upper surface of the casing 40. It is a thing. Holder 42
Is made of insulating resin, and grooves 43, 43 are formed at both ends thereof. An insulating substrate 44 is inserted between the grooves 43, 43, and an elastic contact plate 45 made of a metal such as phosphor bronze is elastically sandwiched between the insulating substrate 44 and the holder 42. At one end of the elastic contact plate 45, two elongated through holes 46, 4 are provided.
6 is provided, and projecting portions 48, 48 projecting from the lower surface of the terminal electrode 47 made of brass are provided in the through holes 46, 46.
The holder 42 is fitted through the through holes 54, 54. The elastic contact plate 45 is folded back, and the other end is elastically contacted with one end of the conductive pattern 49 on the insulating substrate 44.
A through hole 50 is provided at the other end of the insulating substrate 44, and a protruding portion 52 of a conductive plate 51 provided on the lower surface of the insulating substrate 44 is inserted into the through hole 50 and fixed by solder 56 to fix the protruding portion 52. And the conductive pattern 49 are conducted. The conductive plate 51 is pressed against the electrode 41 of the storage means 55. Substrate holding portions 57, 57 are formed on the metal casing 40, the holder 42 is placed on both of the substrate holding portions 57, 57, and the adhesive 53 is applied to the circumferential surface of the holder 42 to attach the metal casing 40 to the metal casing 40. It is fixed. A gap 58 is provided between the insulating substrate 44 and the holder 42 so that the insulating substrate 44 can be deformed.

In the fourth embodiment thus constructed, the metal casing 40 is provided and the electric energy in the inside is led out to the outside through the first and second terminals (40, 41). It has a power storage means 55 and an insulating substrate 44 having electrodes on both ends thereof, and one electrode of the insulating substrate 44 is connected to the first terminal of the power storage means 55 and the second terminal of the power storage means 55 and the insulating substrate. The other electrode of 44 is used as a take-out electrode of the storage battery, and the insulating substrate 44 is arranged in contact with the metal casing 40. The insulating substrate 44 is made of a material having low toughness that can be damaged by the deformation stress of the metal casing 40. Since the conductive pattern having low toughness is formed on the insulating substrate 44, the current path can be interrupted while detecting the deformation of the storage battery.

Next, a fifth embodiment of the present invention will be described with reference to FIGS. 11 and 12. FIG. 11 is a perspective view of a pressure disconnection element (breakage sensor) of the fifth embodiment, and FIG. 12 is a plan view, a vertical sectional view and a bottom view of the pressure disconnection element of the fifth embodiment. 11 and 12, 60 is an insulating substrate,
The insulating substrate 60 has its end portions 60a and 60b incorporated in the holder 61 by snap-in and held. A terminal electrode 62 is attached to the insulating substrate 60, one end of the terminal electrode 62 is formed in a clip shape, and is elastically contacted with a conductive pattern 63 formed on the insulating substrate 60. In addition, a storage portion 65 that stores a transmission member 64 such as urethane is provided on the center side of the lower surface of the terminal electrode 62. The conductive pattern 63 of the insulating substrate 60 is the terminal electrode 62.
The conductive pattern 63 is electrically connected to the conductive pattern 63. Insulating substrate 6
A gap 66 is provided between the upper surface of the insulating substrate 6 and the holder 61, and the insulating substrate 6 until the conductive pattern 63 is broken.
A deformation space of 0 is secured. Reference numeral 67 denotes a metal lead. One end of the metal lead 67 is disposed on the upper surface of the insulating substrate 60 and connected to one end of the conductive pattern 63, and the other end is folded back to the lower surface of the insulating substrate 60 to cover the transmission member 64. It has reached near the edge. Transmission member 6 of metal lead 67
A plurality of slits 68 are provided at the position corresponding to 4. Reference numeral 69 is a groove provided over the entire width of the upper surface of the insulating substrate 60. A rubber conductive connector may be interposed between the terminal electrode 62 and the conductive pattern 63. Further, since the transmission member 64 needs to press the terminal electrode 62 into contact with the positive electrode of the electricity storage means and transmit the deformation of the electricity storage means to the insulating substrate 60, the transmission member 64 is required to have a certain degree of appropriate softness and hardness. In this embodiment, urethane is used as the transmission member 64, but rubber or the like can be used as long as it has an appropriate hardness. Even in the fifth embodiment configured as described above, the same operational effects as those of the respective embodiments are achieved.

It is also possible to replace the insulating substrate shown in FIGS. 9 and 11 with the substrate described in the first embodiment.

[0021]

According to the first aspect of the present invention, it is possible to provide an article deformation detection sensor having a simple structure.
According to the second aspect of the present invention, at least one of the loop-shaped conductive patterns passing a plurality of times has to be broken, so that the reliability of interruption can be increased. According to the third aspect of the invention, when the base material expands and deforms, when the base material cracks, the base material moves in a direction away from the case where the conductive pattern is provided on the lower surface, so that the conductive pattern is reliably blocked. You can According to the invention described in claim 4, when the base material is cracked, the conductive pattern is surely cut off. According to the invention of claim 5, the conductive pattern can be cut without breaking the base material, so that the conductive pattern can be broken with a small pressure. According to the invention described in claims 6 to 12, the current path can be interrupted at the same time when the deformation of the storage battery is detected.

[Brief description of drawings]

FIG. 1 is an exploded perspective view of a first embodiment of the present invention.

FIG. 2 is a sectional view of the first embodiment of the present invention.

FIG. 3 is a circuit diagram of a first embodiment of the present invention.

FIG. 4 is an explanatory diagram showing a cracked state of the ceramic substrate according to the first embodiment of the present invention.

FIG. 5 is a perspective view showing a first modification of the ceramic substrate according to the first embodiment of the present invention.

FIG. 6 is a perspective view showing modified examples 2 and 3 of the ceramic substrate according to the first embodiment of the present invention.

FIG. 7 is a front view of the second embodiment of the present invention.

FIG. 8 is a perspective view of a substrate according to a third embodiment of the present invention.

FIG. 9 is an exploded perspective view of a fourth embodiment of the present invention.

FIG. 10 is an enlarged explanatory view of a main part of the fourth embodiment of the present invention.

FIG. 11 is a perspective view of a pressure disconnection element according to a fifth exemplary embodiment of the present invention.

FIG. 12 is a plan view, a vertical sectional view and a bottom view of a pressure disconnection element according to a fifth embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Ceramic substrate 2 Conductive pattern 6 2nd electrode 7 3rd electrode 12 Groove (destruction part) 22 Conductive pattern 40 Metal casing 44 Insulating substrate 49 Conductive pattern 55 Storage means

Claims (12)

[Claims] 1. A base material having a low toughness that can be destroyed by the deformation stress of an article, a conductive pattern having a low toughness formed on the base material, and a conductive portion connected to the conductive pattern, and at least a broken portion of the base material. A deformation detection sensor for an article, which has electrodes arranged to be sandwiched therebetween. 2. The deformation detection sensor for an article according to claim 1, wherein the conductive pattern is formed in a loop shape that passes through a breaking portion of the base material a plurality of times. 3. The deformation detection sensor for an article according to claim 1, wherein the conductive pattern is provided on a surface of the base material opposite to a surface facing the article side. 4. The deformation of an article according to claim 1, wherein a V groove extending in a direction perpendicular to a line connecting the electrodes of the base material is formed, and the conductive pattern is formed on a surface where the V groove is formed. Detection sensor. 5. A flexible base material, a conductive pattern having a low toughness which is formed on the flexible base material and can be destroyed by the deformation stress of an article, and is connected to the conductive pattern. A deformation detection sensor for an article, comprising electrodes arranged so as to sandwich a broken portion of a flexible base material. 6. A storage battery with a current path breaking function, wherein the deformation detection sensor according to claim 1 is used as a current path of a power storage means. 7. A power storage unit having a housing and a conductive unit, wherein the conductive unit is connected to a part of a current path of the power storage unit and is disposed in contact with the housing, and the conductive unit is A storage battery with a current path breaking function, characterized in that the storage battery is formed of a material having low toughness that can be broken by receiving the deformation stress of the housing. 8. The storage battery according to claim 7, wherein the conductive means is a substrate having low toughness and a conductive pattern having low toughness. 9. The storage battery with a current path interruption function according to claim 7, wherein the conductive means is a conductive pattern having low toughness formed directly on the power storage means. 10. A power storage means having a housing for leading out internal electric energy to the outside via first and second terminals, and a conductive means having electrodes at both ends thereof, one of the conductive means being provided. The electrode of is connected to the first terminal of the storage means,
The second terminal of the power storage means and the other electrode of the conductive means are used as the take-out electrode of the storage battery, and the conductive means is disposed in contact with the housing, and the conductive means receives the deformation stress of the housing. A storage battery with a current path cutoff function, which is characterized by being formed of a material having low toughness that can be destroyed by electric shock. 11. The storage battery with a current path breaking function according to claim 10, wherein the ceramic substrate is held and fixed by a substrate holding means extending from the housing of the power storage means. 12. A storage means having a pair of electrodes, a destruction sensor mounted on the storage means and having a pair of terminals, a holding member for holding the detection sensor, and one terminal of the destruction sensor. A storage battery with a current path interruption function, comprising: a take-out electrode connected to the battery; and a conductive means that connects the other terminal of the destruction sensor and one electrode of the power storage means.