KR102391560B1 - Protective element and battery pack - Google Patents

Abstract

A protection element is equipped with the soluble conductor supported by the insulating substrate, the some heat generating body arrange|positioned on the insulating substrate, the heat generating body drawing electrode electrically connected to each of the some heat generating body, and the heat generating body drawing electrode.

Description

PROTECTIVE ELEMENT AND BATTERY PACK

The present invention relates to a protection element for protecting a circuit connected to the current path by blocking the current path, and a battery pack using the protection element.

Most of the secondary batteries that can be repeatedly used because they are rechargeable are provided to the user in a state of being processed into a battery pack. In particular, when a lithium ion secondary battery having a high weight energy density is used, in order to ensure the safety of users and electronic devices, in general, several protection circuits are provided in the battery pack from the viewpoint of overcharge protection and overdischarge protection. is built into For this reason, the battery pack has a function of shutting off the output in a predetermined case.

Most electronic devices using a lithium ion secondary battery perform an operation related to overcharge protection or overdischarge protection of the battery pack by turning on/off the output using a FET switch built into the battery pack. However, when the FET switch is short-circuited or destroyed for some reason or a lightning surge is applied, when a large current flows instantaneously, the output voltage is abnormally lowered due to the life of the battery cell, or, conversely, an excessive abnormal voltage is output Even in this case, the battery pack and electronic device must be protected from accidents such as fire. Therefore, in any conceivable abnormal state, in order to safely cut off the output of the battery cell, a protection element composed of a fuse element having a function of blocking a current path according to an external signal is used.

As a protection element mounted on the protection circuit for such a lithium ion secondary battery etc., the protection element provided with a heat generating body is used as patent documents 1 and 2 describe. In this protection element, the soluble conductor introduce|transduced into a current path|route is melt-cut using the heat_generation|fever of a heat generating body.

Japanese Patent Laid-Open No. 2010-3665 Japanese Laid-Open Patent Publication No. 2014-32769

By the way, in order to use a protection element for the use with comparatively low electric current capacity, such as a cellular phone and a notebook computer, a soluble conductor (fuse) has a current capacity of about 15 A at most. Since the use of a lithium ion secondary battery is expanding in recent years, adoption of a lithium ion secondary battery for the use of a larger current is examined, and adoption of a lithium ion secondary battery has already been disclosed for some uses. The use of this large current is, for example, electric tools, such as an electric screwdriver, and transport apparatuses, such as a hybrid car, an electric vehicle, and an electric assist bicycle. In the use of these large currents, a large current exceeding several tens of A to 100 A may flow, especially at the time of starting or the like. Realization of a protection element corresponding to such a large current capacity is desired.

Therefore, even when a large soluble conductor is used in order to cope with a large current, it is possible to realize stable heat generation operation by maintaining fast melting and breaking properties without lowering the power density and alleviating the thermal shock to the insulated substrate. It is desirable to provide a protection element and a battery pack.

The protection element in one embodiment of the present invention includes an insulating substrate, a plurality of heating elements disposed and formed on the insulating substrate, a heating element extraction electrode electrically connected to each of the plurality of heating elements, and the heating element extraction electrode. It is provided with a soluble conductor supported by

Moreover, the battery pack in one Embodiment of this invention includes one or more battery cells, the protection element connected to the one or more battery cells so that the electric current which flows through the one or more battery cells may be interrupted|blocked, and the A current control element is provided that detects each voltage value of one or more battery cells and controls a current for heating the protection element. This protection element comprises an insulating substrate, a plurality of heating elements arranged and formed on the insulating substrate, a heating element drawing electrode electrically connected to each of the plurality of heating elements, and a soluble conductor supported by the heating element extraction electrode. .

According to the protection element and battery pack in one Embodiment of this invention, while a heat generating body extraction electrode is electrically connected with each of a some heat generating body, a soluble conductor is supported by the heat generating body drawing electrode. In this case, since the heat generating element is divided into plural, the thermal shock to the insulating substrate due to heat generation is alleviated while maintaining the same amount of heat generated when the heat generating element is not divided into plural. That is, when a heat generating element is divided|segmented into plurality, since a diffusion peak falls in the heat distribution of an insulated substrate, the thermal shock to an insulated substrate is relieve|moderated. On the other hand, even if a heat generating body is divided|segmented, since the total calorific value is maintained equally, the time required for melting and cutting of a soluble conductor does not become long. Therefore, stable heat generation operation can be realized, suppressing cracking of an insulated substrate, even when a soluble conductor is enlarged in order to respond to large current capacity and the electric power of a heat generating body is increased.

BRIEF DESCRIPTION OF THE DRAWINGS It is sectional drawing which shows the protection element of one Embodiment of this invention.
It is a top view which shows the protection element of one Embodiment of this invention.
3 : is sectional drawing which shows the protection element by which the soluble conductor was melted using the self-heating accompanying an overcurrent.
It is sectional drawing which shows the protection element by which the soluble conductor was cut by melting using the heat_generation|fever of a heat generating body.
5 : is sectional drawing which shows the other protection element in one Embodiment of this invention.
6 : is sectional drawing which shows the other protection element in one Embodiment of this invention.
7 : is sectional drawing which shows the other protection element in one Embodiment of this invention.
It is a figure which shows an example of the circuit structure of the battery pack to which the protection element of one Embodiment of this invention was applied.
It is a circuit diagram of the protection element in one Embodiment of this invention.
It is sectional drawing which shows the protection element in which the suction hole was formed in the insulated substrate.
11 : is a top view which shows the protection element in which the suction hole was formed in the insulated substrate.
12 : is sectional drawing which shows the protection element in which the suction hole was formed in the insulating substrate, and has shown the state after melting of a soluble conductor.
13 : is a top view which shows the protection element of a comparative example.
14 : is sectional drawing which shows the protection element of a reference example.
15 : is a top view which shows the protection element of a reference example.

EMBODIMENT OF THE INVENTION Hereinafter, the protection element of one Embodiment to which this invention was applied, and the battery pack using the protection element are demonstrated in detail, referring drawings. In addition, this invention is not limited only to the following embodiment, It goes without saying that various changes are possible within the range which does not deviate from the summary of this invention. In addition, since a drawing is a schematic drawing, the ratio of each dimension, etc. may differ from the actual ratio etc. in some cases. Specific dimensions and the like should be judged in consideration of the following description. Moreover, it goes without saying that there are cases where the dimensions and ratios of the drawings are also different from each other.

[First embodiment]

The protection element 1 of one Embodiment of this invention, as shown to FIG. 1 and FIG. 2, the some heating element 3 arrange|positioned on the insulating substrate 2, the insulating substrate 2, and the The heat generating body lead-out electrode 4 electrically connected to each of the some heat generating body 3, and the soluble conductor 5 supported by the heat generating body drawing electrode 4 are provided. Moreover, the protection element 1 is equipped with the 1st electrode 11 and the 2nd electrode 12, and the insulating substrate 2 is arrange|positioned between the 1st electrode 11 and the 2nd electrode 12. has been In this protection element 1, while the one end of the soluble conductor 5 is arrange|positioned on the 1st electrode 11, the one end is electrically connected with the 1st electrode 11, the soluble conductor ( The other end of 5) is disposed on the second electrode 12 , and the other end thereof is electrically connected to the second electrode 12 .

[First electrode and second electrode]

The first electrode 11 and the second electrode 12 are connection terminals for connecting the protection element 1 to an external circuit, and contain metal or the like. While each of the 1st electrode 11 and the 2nd electrode 12 is connected with the soluble conductor 5 through the connection material 7, such as solder, in the inside of the protection element 1, the It is mutually connected via the soluble conductor 5. Thereby, in the protection element 1, the electric current path|route from the 1st electrode 11 to the 2nd electrode 12 via the soluble conductor 5 is comprised. This current path is attached to the external circuit as a part of the first electrode 11 and the second electrode 12 connected to the connection terminal of the external circuit. And in the protection element 1, when the overcurrent exceeding a rating flows through the soluble conductor 5, the soluble conductor 5 will melt|fuse using self-heating. Thereby, as shown in FIG. 3, since the soluble conductor 5 is cut by melting between the soluble conductor 5 and one of the 1st electrode 11 and the 2nd electrode 12, it is charge/discharge of an external circuit. The path is blocked. Alternatively, in the protection element 1, when the heat generating element 3 is energized, the heat generating element 3 generates heat. Thereby, as shown in FIG. 4, since the soluble conductor 5 melts, while the soluble conductor 5 is fused between the 1st electrode 11 and the heat generating body extraction electrode 4, a 2nd electrode ( The soluble conductor 5 is cut by melting between 12) and the heating-element extraction electrode 4 . Therefore, since the molten conductor 5a which is the molten material of the soluble conductor 5 aggregates on the heat generating body lead-out electrode 4, the electric current path of an external circuit is interrupted|blocked.

In the protection element 1, the 1st electrode 11 and the 2nd electrode 12 are led out to the outside from the inside of the outer casing 10, and are supported by the outer casing 10. Moreover, in the protection element 1, since the insulating board|substrate 2 is arrange|positioned in the center space in the inside of the outer casing 10, the 1st electrode 11 and the 2nd electrode 12 are insulated. The substrate 2 is adjacent.

The outer casing 10 contains any one type or two or more types of engineering plastics excellent in heat resistance, such as PPS (Polyphenylenesulfide: Polyphenylenesulfide), for example. Moreover, when shaping|molding so that it may become a predetermined shape, the outer casing 10 may be shape|molded so that it may become integral with the 1st electrode 11 and the 2nd electrode 12 using insert molding etc.

In addition, the 1st electrode 11 and the 2nd electrode 12 may be arrange|positioned on the insulating material adjacent to the insulating substrate 2, and may be formed. This insulating material contains an epoxy resin etc., for example. Moreover, as shown in FIG. 5, the 1st electrode 11 and the 2nd electrode 12 apply|coat a high-melting-point metal paste using a printing method etc., among the surface 2a of the insulated substrate 2, It may be formed in a pair of opposing side edge parts.

[Insulation Substrate]

The insulating substrate 2 contains any one type or two or more types of materials which have insulating properties, such as alumina, glass ceramics, mullite, and a zirconia, for example. In addition, although the material used for printed wiring boards, such as a glass epoxy board|substrate and a phenol board|substrate, may be used, it is necessary to pay attention to the temperature at the time of fuse fusing.

[Heating element]

The heat generating element 3 is covered with the insulating member 13 while being arrange|positioned on the surface 2a of the insulated substrate 2 . The heat generating element 3 contains any one type or two or more types of materials which have a comparatively high resistance value and the electroconductive material which heat|fever-generates when electricity is supplied. The material having this conductivity is, for example, W, Mo, Ru, an alloy containing one or more of these as a main component, a composition containing one or more of these as a main component, and a compound containing one or more of these as a main component. A paste containing a mixture of a powdery substance such as these alloys and a resin binder is applied on the insulating substrate 2 to form a predetermined pattern using a screen printing technique, and then the paste is fired, so that the heating element 3 ) is formed.

In the protection element 1, the some heat generating element 3 is paralleled by the predetermined space|interval, and, as shown in FIG. 1, for example, two heat generating elements 3A, 3B are formed. Thus, in the protection element 1, the heat to the insulated substrate 2 due to heat generation is maintained while the heat generating element 3 is divided into plural, thereby maintaining an amount of heat equivalent to that in the case where the heating element 3 is not divided into plural. shock is alleviated. That is, in the protection element 1, since the diffusion peak falls in the heat distribution of the insulated substrate 2 when the heat generating body 3 is divided|segmented into plurality, the thermal shock to the insulated substrate 2 is relieve|moderated. On the other hand, in the protection element 1, even if the heat generating body 3 is divided|segmented, since the total calorific value of the heat generating body 3 is maintained equally, the time required for the fusing of the soluble conductor 5 does not become long. Therefore, in the protection element 1, while increasing the size of the soluble conductor 5 in order to respond to a large current capacity, also when the electric power of the heat generating body 3 is increased, while suppressing that the insulated substrate 2 cracks, Stable heat generation operation can be realized.

As shown in FIG. 2 , the soluble conductor 5 extends from the first electrode 11 to the second electrode 12 . Each of heat generating body 3A, 3B has the rectangular-shaped planar shape which makes the longitudinal direction the direction to cross|intersect (for example, orthogonal) with the extending direction of the soluble conductor 5. One end of each of the heating elements 3A and 3B in the longitudinal direction is connected to the first heating element electrode 15 disposed on the surface 2a of the insulating substrate 2 via the heating element connection electrode 17a In addition, each other end of each of the heat generating elements 3A and 3B in the longitudinal direction is disposed on the surface 2a of the insulating substrate 2 via the heat generating element connection electrode 17b, and the second heat generating element electrode 16 is formed. is connected with

The 1st heat generating body electrode 15 is connected with the heat generating body lead-out electrode 4 while being connected with each one end of the some heat generating body 3 . The 2nd heat generating element electrode 16 becomes an external connection electrode when the protection element 1 is connected to an external circuit while being connected with each other end of the some heat generating element 3 . The protection element 1 is attached to the power supply path formed in the external circuit in order to feed the heat generating body 3 by being connected with an external circuit via the 2nd heat generating element electrode 16. As shown in FIG.

The first heating element electrode 15 and the second heating element electrode 16 contain, for example, any one type or two or more types of high-melting-point metals. The high-melting-point metal is, for example, Ag, Cu, or an alloy containing one or more of them as a main component. A paste containing a mixture of this high-melting-point metal and a resin binder is applied on the insulating substrate 2 to form a predetermined pattern using a screen printing technique, and then the paste is fired or the like, so that the first heating element electrode ( 15) and the second heating element electrode 16 are formed.

The heating element 3 generates heat when the first heating element electrode 15 and the second heating element electrode 16 are energized. That is, the heat generating body 3 is energized in the longitudinal direction. Accordingly, even when the heating element 3 is cracked along the longitudinal direction, the conduction path between the first heating element electrode 15 and the second heating element electrode 16 is not well blocked, so that the heating element 3 is Electricity and heat generation by the heat generating element 3 are also not easily stopped. On the other hand, as shown in Fig. 15 to be described later, since heating element connection electrodes are formed on both sides of the heating element 3 in the width direction orthogonal to the longitudinal direction, the heating element 3 is energized in the width direction to generate heat. In this case, when the heating element 3 cracks along the longitudinal direction, the energization path between the first heating element electrode 15 and the second heating element electrode 16 is easily cut off, so before the soluble conductor 5 is melted. There exists a possibility that heat_generation|fever of the heat generating body 3 may stop.

The insulating member 13 contains glass, for example. Moreover, in the protection element 1, in order to transmit the heat which generate|occur|produced in the heat generating body 3 to the soluble conductor 5 efficiently, also between the some heat generating body 3 and the insulated substrate 2 By forming an insulating member , you may make it form the heat generating body 3 inside the insulating member 13 arrange|positioned on the surface 2a of the insulating substrate 2 .

[Heating element extraction electrode]

The heat generating body extraction electrode 4 comprises the electric power feeding path|route with respect to the heat generating body 3 while supporting the soluble conductor 5 connected to the 1st electrode 11 and the 2nd electrode 12. This heat generating body extraction electrode 4 has the lead part 4a which contact|connects the 1st heat generating body electrode 15, and the connection part 4b to which the soluble conductor 5 is connected while arrange|positioning on the insulating member 13. . In the heat generating body extraction electrode 4, while the connection part 4b is arrange|positioned between the 1st electrode 11 and the 2nd electrode 12, the 1st electrode 11 and the 2nd through the soluble conductor 5 It is connected to the electrode 12 . Moreover, the heat generating body extraction electrode 4 cuts the soluble conductor 5 by melting by transmitting the heat generated in the heat generating body 3 to the soluble conductor 5 while being heated by the heat generating body 3 . Moreover, when the 1st electrode 11 and the 2nd electrode 12 are parted while the melt (molten conductor 5a) of the soluble conductor 5 aggregates when the soluble conductor 5 melts, a heat generating body is taken out. The electrode 4 blocks the current path between the first electrode 11 and the second electrode 12 . At this time, since the heat generating body lead-out electrode 4 is heated by the heat generating body 3, it makes it easy to aggregate the molten conductor 5a.

The heat generating element lead-out electrode 4 is arranged so that the connecting portion 4b partially overlaps with respect to each of the plurality of heat generating elements 3 via the insulating member 13 . Therefore, since the heat generated in each heat generating element 3 is easily transmitted to the heat generating body drawing electrode 4 through the insulating member 13 efficiently, the heat generating body drawing electrode 4 is a soluble conductor 5 quickly While heating, the soluble conductor 5 can be melt|melted quickly. That is, in the protection element 1, when the plurality of heat generating elements 3 generate heat, respectively, the heat generated in the plurality of heat generating elements 3 is generated by the insulating member 13 and the heat generating element extraction formed on the insulating member 13 . Since it transmits to the soluble conductor 5 through the electrode 4, the soluble conductor 5 is heated. At this time, in the protection element 1, since the heat generating element extraction electrode 4 is arrange|positioned so that it may overlap with each of the several heat generating element 3 dividedly arrange|positioned, the heat which generate|occur|produced in the heat generating element 3 is heat generating element extraction. While being transmitted to the electrode 4 efficiently, the soluble conductor 5 is cut by melting quickly. Moreover, in the protection element 1, since the heat which generate|occur|produced in the heat generating body 3 becomes easy to transmit by the heat generating body lead-out electrode 4 and the soluble conductor 5, the thermal shock to the insulating substrate 2 is relieved, and Together, the insulating substrate 2 and the heating element 3 are less likely to crack.

In addition, as shown in FIG. 1, although the heat generating body lead-out electrode 4 may overlap partially with respect to both heat generating body 3A, 3B, it may partially overlap only with respect to one of heat generating body 3A, 3B. . Considering the thermal conduction to the soluble conductor 5 and the mitigation effect of the thermal shock to the insulating substrate 2, the heating element extraction electrode 4 partially overlaps with respect to both of the heating elements 3A and 3B. desirable.

The heat generating body lead-out electrode 4 contains any one type or two or more types of high melting-point metals, for example. The high-melting-point metal is, for example, Ag, Cu, or an alloy containing them as a main component. A paste containing a mixture of this high melting point metal and a resin binder is applied on the insulating member 13 and the first heating element electrode 15 to form a predetermined pattern using a screen printing technique, and then the paste is fired By becoming the etc., the heat generating body extraction electrode 4 is formed.

And the heat generating body extraction electrode 4 is connected with the soluble conductor 5 connected to the 1st electrode 11 and the 2nd electrode 12 through the connection materials 7, such as solder. Moreover, since the molten conductor 5a will aggregate when the soluble conductor 5 heated by the heat generating body lead-out electrode 4 melts, the electric current path between the 1st electrode 11 and the 2nd electrode 12 is interrupted|blocked. do.

Further, in the protection element 1, as shown in Fig. 1, the heating elements 3A and 3B are arranged on both sides of the boundary with the center of the insulating substrate 2 as a boundary, and the heating element extraction electrodes ( It is preferable that 4) is arrange|positioned and formed in the area|region which reaches the center of the insulating substrate 2, and its periphery. In the insulated substrate 2, while the cooling effect resulting from heat radiation is high, so that it approaches an outer edge part, there exists a tendency for a heat|fever to escape hard in the center part farthest from the outer edge part. For this reason, in the central part of the insulated substrate 2, since the stress resulting from thermal expansion becomes large, the insulated substrate 2 is easy to crack. Therefore, if the heating elements 3A and 3B are disposed in the region avoiding the central portion of the insulated substrate 2, the heat generated by the heating elements 3A, 3B is accumulated in the central portion of the insulated substrate 2, Even when the insulated substrate 2 is cracked due to the stress accompanying thermal expansion, the influence by the crack becomes difficult to exert on heat generating body 3A, 3B.

In addition, when the heat generating element lead-out electrode 4 is arranged and formed in the region extending to the center and the periphery of the insulating substrate 2, in the protection element 1, the heat generated in the heat generating elements 3A and 3B is not easily dissipated. In order to concentrate on the central part of the insulated substrate 2 which does not do, the heat is transmitted to the soluble conductor 5 efficiently, without being disperse|distributed to the insulated substrate 2 whole. Thereby, the soluble conductor 5 is heated efficiently. At the same time, in the protection element 1, when the heat which generate|occur|produced in the heat generating elements 3A, 3B concentrates on the central part of the insulated substrate 2, the heat will be transmitted to the soluble conductor 5 through the heat generating body extraction electrode 4 . Thereby, since the heat generated in the heat generating elements 3A and 3B is not easily dissipated, and the stress accompanying thermal expansion is not easily accumulated in the central portion of the insulated substrate 2, the insulated substrate 2 ) is not easily cracked.

Moreover, in each other end side of the some heat generating body 3, the 2nd heat generating body electrode 16 is arrange|positioned so that it may oppose each of the some heat generating body 3, and the insulated substrate 2 is a heat generating body. In the region where (3) is not arranged, it is connected to the terminal portion of the external circuit via the second heating element electrode 16 using a bonding material such as solder. Thereby, in the protection element 1, since the insulating substrate 2 is fixed in the area|region where the heat generating body 3 is not arrange|positioned, when the heat generating body 3 heat|fever-generates, the heat generating body 3 is arrange|positioned and formed, Stress is generated in the insulating substrate 2 in the region where it is not. Thereby, even if the insulating substrate 2 cracks, the generation|occurrence|production position of the crack is controlled to the area|region in which the heat generating body 3 is not arrange|positioned. In particular, when the two heating elements 3A and 3B are arranged on both sides of the boundary with the center of the insulation substrate 2 as a boundary, the heat generated by the heating elements 3A, 3B is not easily radiated from the insulation substrate 2 ) and when stress accompanying thermal expansion accumulates, since the second heating element electrode 16 becomes a fixed point, the crack generation position is controlled in the region between the heating elements 3A and 3B. easy to become Accordingly, even when the insulating substrate 2 is cracked, the situation in which the heat generation stops due to the cracking of the heating elements 3A and 3B is prevented.

Here, as shown in Figs. 1 and 2, a through hole 20 (conductive through hole) formed in the inner wall surface of the conductive layer 61 is formed in the insulating substrate 2, and the conductive layer 61 is formed therein. By forming the connection terminal portion 62 electrically connected to the second heating element electrode 16 through the back surface 2b of the insulating substrate 2, the second heating element electrode 16 is You may make it fixed while being connected with the terminal part of an external circuit. In the protection element 1, when the through-hole 20 is formed in the fixing point of the insulated substrate 2, the insulated substrate 2 makes the through-hole 20 as a starting point and becomes easy to crack. Thereby, a situation in which heat generation stops due to cracking of the heat generating elements 3A and 3B is prevented. In addition, after FIG. 3, illustration of the above-mentioned conductive layer 61 and the connection terminal part 62 is abbreviate|omitted.

In addition, the 2nd heating element electrode 16 may be fixed while being connected to the terminal part of an external circuit using the solder bridge arrange|positioned from the front surface 2a to the back surface 2b of the insulated substrate 2 . Also in this case, in the protection element 1, since the insulating substrate 2 is fixed in the area|region where the heat generating element 3 is not arrange|positioned, the generation|occurrence|production position of a crack is not arrangement|positioning of the heat generating element 3 Controlled in a non-existent area.

[Soluble Conductor]

The soluble conductor 5 melts in an overcurrent state. This soluble conductor 5 contains any 1 type or 2 or more types of the electroconductive material which can be cut by melting. This conductive material is, for example, a BiPbSn alloy, a BiPb alloy, a BiSn alloy, a SnPb alloy, a PbIn alloy, a ZnAl alloy, an InSn alloy, and a PbAgSn alloy other than the SnAgCu-based Pb-free soldering. In addition, the soluble conductor 5 may be a laminated body of high melting-point metals, such as alloys which have Ag, Cu, and one or more types thereof as a main component, and low-melting-point metals, such as solder or Pb-free solder which has Sn as a main component.

Such a soluble conductor 5 is formed by forming a high-melting-point metal layer into a film on low-melting-point metal foil using a plating technique. However, the soluble conductor 5 may be formed using another well-known lamination technique and film formation technique. In addition, the soluble conductor 5 makes a high-melting-point metal layer into an inner layer, and is good also considering a low-melting-point metal layer as an outer layer. Moreover, the multilayer structure of 4 or more layers in which the soluble conductor 5 was laminated|stacked alternately with the low-melting-point metal layer and the high-melting-point metal layer may be sufficient as it. Thus, the soluble conductor 5 can be formed so that it may become various structures.

Moreover, since the soluble conductor 5 does not self-heat in the state in which a predetermined|prescribed rated current is flowing, it is not melted. On the other hand, since the soluble conductor 5 will self-heat when the electric current of a value higher than a rating flows, it melts. Accordingly, the current path between the first electrode 11 and the second electrode 12 is blocked. Moreover, since the soluble conductor 5 will be heated by the heat generating body 3 when the heat generating body 3 heat|fever-generates by electricity supply, it will cut by melting. Accordingly, the current path between the first electrode 11 and the second electrode 12 is blocked. At this time, in the soluble conductor 5, since the molten low-melting-point metal erodes a high-melting-point metal, the high-melting-point metal melts at temperature lower than a melting temperature. Therefore, the soluble conductor 5 is fusion-cut in a short time using the erosion action of the high-melting-point metal by a low-melting-point metal.

Moreover, in the soluble conductor 5, when the high melting-point metal used as an outer layer is laminated|stacked on the low-melting-point metal used as an inner layer, fusing temperature is significantly reduced rather than the chip fuse etc. which consist of a high-melting-point metal. Therefore, in the soluble conductor 5, compared with the chip fuse of the same size, while a cross-sectional area becomes large, a current rating improves significantly. Moreover, compared with the chip fuse of the same current rating, while miniaturization and thickness reduction are attained, it is excellent in quick-melting property.

Moreover, in the soluble conductor 5, the phenomenon to which an unusually high voltage is instantaneously applied to the electric circuit with which the protection element 1 was attached, tolerance (pulse resistance) with respect to a so-called surge improves. That is, the soluble conductor 5 must not be fused by melting, for example, when an electric current of 100 A flows for several msec. In this regard, a large current flowing in an extremely short time flows through the surface layer of the conductor (skin effect). When the soluble conductor 5 contains a high melting point metal such as Ag plating having a low resistance value as an outer layer, the current applied due to the surge flows easily, so that the melting of the soluble conductor 5 due to self-heating is prevented. . Therefore, in the soluble conductor 5, when a low-melting-point metal is coat|covered with high-melting-point metal, compared with the fuse which consists of a solder alloy, tolerance with respect to a surge improves significantly.

Moreover, the flux (not shown) is apply|coated to the soluble conductor 5 for the improvement of the wettability at the time of oxidation prevention and fusion cutting, etc.

[Heating element]

Moreover, as shown in FIG. 6, in the protection element 1, the heat generating body 3 may be arrange|positioned on the back surface 2b of the insulated substrate 2, and may be formed. The heat generating element 3 is disposed on the back surface 2b of the insulating substrate 2 and is covered with the insulating member 13 on the back surface 2b.

One end of the heat generating body 3 is electrically connected to the heat generating body lead-out electrode 4 and the soluble conductor 5 arrange|positioned on the heat generating body lead-out electrode 4 via the heat generating body electrode which is not shown in figure. Moreover, the other end of the heat generating body 3 is connected to the 2nd heat generating body electrode 16. As shown in FIG.

Moreover, as shown in FIG. 7, in the protection element 1, the heat generating body 3 may be arrange|positioned inside the insulating substrate 2, and may be formed. In this case, the heat generating body 3 does not need to be coat|covered with insulating layers, such as glass. Moreover, one end of the heat generating body 3 is electrically connected to the heat generating body lead electrode 4 and the soluble conductor 5 arrange|positioned on the heat generating body lead electrode 4 via the heat generating body electrode which is not shown in figure. Moreover, the other end of the heat generating body 3 is connected to the 2nd heat generating body electrode 16. As shown in FIG.

[Circuit configuration]

When the protection element 1 is attached to a battery pack, for example, since the soluble conductor 5 will cut by self-fusion at the time of an overcurrent, the charging/discharging path|route of a battery pack will be interrupted|blocked. Moreover, since the soluble conductor 5 heated by the heat generating body 3 will be fused by melting, when the protection element 1 heats up while the heat generating body 3 is energized according to the overvoltage of a battery cell, charging/discharging of a battery pack block the path

The battery pack 30 is equipped with the battery stack 35 which consists of battery cells 31-34 which are a total of four lithium ion secondary batteries, for example, as shown in FIG.

The battery pack 30 includes a battery stack 35 , a charge/discharge control circuit 40 for controlling charging and discharging of the battery stack 35 , and a protection element for stopping a charging operation when the battery stack 35 is abnormal. 1) (protection element to which the present invention is applied), a detection circuit 36 for detecting the voltage of each battery cell 31 to 34, and the operation of the protection element 1 according to the detection result of the detection circuit 36 A current control element 37 which is a switch element to control is provided.

In the battery stack 35, the battery cells 31 to 34 that require control for protection from an overcharge state and an overdischarge state are connected in series. This battery stack 35 is detachably connected to the charging device 45 via the positive electrode terminal 30a and the negative electrode terminal 30b of the battery pack 30, and the charging voltage from the charging device 45 is is authorized The battery pack 30 charged by the charging device 45 can operate the electronic device by being connected to the electronic device which operates using the battery via the positive electrode terminal 30a and the negative electrode terminal 30b.

The charge/discharge control circuit 40 includes two current control elements 41 and 42 connected in series to a current path from the battery stack 35 to the charging device 45 , and the current control elements 41 and 42 . A control unit 43 for controlling the operation is provided. The current control elements 41 and 42 include, for example, field effect transistors (hereinafter, referred to as FETs), and since the gate voltage is controlled by the control unit 43 , the current of the battery stack 35 . Controls the state (conducting and blocking) of the path. The control unit 43 operates by receiving power supply from the charging device 45 , and according to the detection result by the detection circuit 36 , when the battery stack 35 is in an over-discharge state or an over-charge state, a current path Controls the operation of the current control elements 41 and 42 so that .

The protection element 1 is introduced into the charge/discharge current path between the battery stack 35 and the charge/discharge control circuit 40, for example, and the operation of the protection element 1 is performed by the current control element 37 is controlled by

The detection circuit 36 is connected with each battery cell 31-34, and transmits each voltage value detected in each battery cell 31-34 to the control part 43 of the charge/discharge control circuit 40. supply Moreover, the detection circuit 36 outputs the control signal for controlling the current control element 37, when any one of the battery cells 31-34 becomes an overcharge voltage state or an overdischarge voltage state.

The current control element 37 includes, for example, an FET. This current control element 37 protects when, according to the detection signal output from the detection circuit 36, the voltage value of the battery cells 31 to 34 becomes a voltage exceeding a predetermined overdischarge state or overcharge state. The element 1 is operated. Accordingly, the charging/discharging current path of the battery stack 35 is cut off regardless of the switch operation of the current control elements 41 and 42 .

The protection element 1 to which this invention used for the battery pack 30 which has the above structures was applied has a circuit structure as shown in FIG. That is, in the protection element 1, the 1st electrode 11 is connected with the battery stack 35 side, and the 2nd electrode 12 is connected with the positive electrode terminal 30a side. Thereby, the soluble conductor 5 is introduced into the charging/discharging path|route of the battery stack 35 in series. Moreover, in the protection element 1, while the heat generating element 3 is connected with the current control element 37 via the 2nd heat generating element electrode 16, the heat generating element 3 is connected with the open end of the battery stack 35 and connected. Thereby, one end of the heat generating body 3 is connected with the one open end of the battery stack 35 via the heat generating body lead-out electrode 4, the soluble conductor 5, and the 1st electrode 11. The other end of the heating element 3 is connected to the other open end of the current control element 37 and the battery stack 35 via the second heating element electrode 16 . Thereby, while the electric power supply path|route to the heat generating element 3 is formed, electricity supply to the heat generating element 3 is controlled by the current control element 37. As shown in FIG.

[Operation of protection element]

Since the soluble conductor 5 melts with self-heating in the protection element 1 when the overcurrent exceeding a rating flows through the battery pack 30, the charging/discharging path|route of the battery pack 30 is interrupted|blocked.

In addition, the detection circuit 36 outputs a cutoff signal to the current control element 37 when an abnormal voltage of any of the battery cells 31 to 34 is detected. This current control element 37 controls the current so that the heating element 3 is energized according to the cut-off signal. In the protection element 1, since an electric current flows to the heat generating body 3 from the battery stack 35 through the 1st electrode 11, the soluble conductor 5, and the heat generating body extraction electrode 4, the heat generating body 3 starts to exotherm. Thereby, in the protection element 1, when the soluble conductor 5 is heated by the heat generating body 3, since the soluble conductor 5 is fusion-cut, the charging/discharging path|route of the battery stack 35 is interrupted|blocked (FIG. 3).

At the time of melting of the soluble conductor 5 using the heat generating body 3 at the time of an overvoltage at this time, in the protection element 1, since the heat generating body 3 is divided|segmented into plurality, the heat generating body 3 is plural. The thermal shock to the insulating substrate 2 due to heat generation is alleviated while maintaining the same amount of heat as that in the case where it is not divided into . Therefore, in the protection element 1, while the soluble conductor 5 is enlarged in order to respond to large current capacity, also when the electric power of the heat generating body 3 is increased, the time required for the fusing of the soluble conductor 5 While this does not become long, the insulated substrate 2 becomes hard to crack, and stable heat generation operation|movement can be implement|achieved.

Moreover, in the protection element 1, the heat generated by each heat generating element 3 by arrangement|positioning and forming so that the heat generating body lead-out electrode 4 may overlap with the some heat generating body 3 through the insulating member 13 partially is an insulating member Since it transmits efficiently to the soluble conductor 5 through (13), it can melt|melt while heating the soluble conductor 5 quickly. Moreover, in the protection element 1, the heat which generate|occur|produced in the heat generating body 3 becomes easier to transmit to the heat generating body extraction electrode 4 and the soluble conductor 5. Thereby, since the thermal shock to the insulated substrate 2 is relieved, the insulated substrate 2 and the heat generating body 3 become hard to crack.

Moreover, in the protection element 1, when the soluble conductor 5 contains a high-melting-point metal and a low-melting-point metal, using the erosion action of the high-melting-point metal by the melted low-melting-point metal, the soluble conductor 5 for a short time can be fused to

Moreover, in the protection element 1, since the electric power supply path|route with respect to the heat generating body 3 is interrupted|blocked by the soluble conductor 5 being cut by melting, the heat_generation|fever of the heat generating body 3 stops.

The protection element of one embodiment of the present invention is not limited to the case of use in a battery pack in which a lithium ion secondary battery is mounted, but can of course be applied to various uses requiring blocking of a current path according to an electrical signal.

[Second embodiment]

Moreover, in the protection element of one Embodiment to which this invention was applied, as shown in FIG. 10, the melt of the soluble conductor 5 so that the heat generating body extraction electrode 4, the insulating member 13, and the insulating substrate 2 may be penetrated. You may provide the suction hole 51 for attracting|sucking the phosphorus molten conductor 5a. In addition, in the following description, while attaching|subjecting the same code|symbol about the same member as the protection element 1 mentioned above, the detailed description about the same member is abbreviate|omitted.

In the protection element 50 in which the suction hole 51 was formed, the soluble conductor 5 melts using the self-heating accompanying an overcurrent, or the soluble conductor 5 heat_generation|fever of the heat generating body 3 accompanying an overvoltage When used and melted, the volume of the molten conductor 5a decreases because the molten conductor 5a is attracted to the inside of the suction hole 51 using the capillary phenomenon. In the protection element 50, since the molten conductor 5a is attracted|sucked by the suction hole 51 even when a molten amount increases by increasing the cross-sectional area of the soluble conductor 5 in order to respond to a large current use, the molten conductor The volume of (5a) decreases.

Thereby, in the protection element 50, the soluble conductor 5 becomes easy to cut by melting quickly. Moreover, in the protection element 50, even if arc discharge generate|occur|produces at the time of melting of the soluble conductor 5 using the self-heating accompanying an overcurrent, the scattering of the molten conductor 5a resulting from the arc discharge is reduced. Thereby, while the fall of insulation resistance is prevented, the short circuit failure resulting from the molten conductor 5a adhering to the circuit around the soluble conductor 5 is prevented.

A conductive layer 52 is formed on the inner wall surface of the suction hole 51 . By forming the conductive layer 52 , the suction hole 51 easily attracts the molten conductor 5a. The conductive layer 52 contains, for example, any one type or two or more types of electroconductive materials. The conductive material is, for example, copper, silver, gold, iron, nickel, palladium, lead, tin, or an alloy containing them as a main component. The conductive layer 52 is formed on the inner wall surface of the suction hole 51 by depositing a conductive material (conductive paste) into a film using a known method such as an electrolytic plating method and a printing method.

Moreover, it is preferable that the suction hole 51 is a through-hole extended in the thickness direction of the insulated substrate 2 . Thereby, in the suction hole 51, it attract|sucks until the molten conductor 5a reaches the back surface 2b of the insulated substrate 2. Thereby, since more molten conductor 5a is attracted|sucked, the volume of the molten conductor 5a reduces more in the place where the soluble conductor 5 was cut by fusion. In addition, the suction hole 51 may be a non-penetrating hole.

Moreover, as shown in FIG. 11, the heat generating body extraction electrode 4 is arrange|positioned through the insulating member 13 on the surface 2a of the insulated substrate 2, and the suction hole 51 is the heat generating body extraction electrode. It is formed in the position corresponding to the center position in the width direction of (4). In addition, the number of the suction holes 51 may be plural. Since the path|route which attracts the molten conductor 5a increases, more molten conductor 5a is attracted|sucked by the suction hole 51. As shown in FIG. Thereby, the place where the soluble conductor 5 was cut by melting WHEREIN: The volume of the molten conductor 5a reduces more. Here, the some suction hole 51 is arrange|positioned so that it may line up in a line, ie, linear, for example.

In addition, the conductive layer 52 formed on the inner wall surface of the suction hole 51 is connected to the heat generating body extraction electrode 4 . It is preferable that the surface of the conductive layer 52 and the surface of the heat generating body lead-out electrode 4 exist in the same plane. The conductive layer 52 and the heat generating body extraction electrode 4 may be integrated. Thereby, in the protection element 50, the molten conductor 5a aggregated on the heating element extraction electrode 4 gets wet on the surface of the heating element extraction electrode 4 and the surface of the conductive layer 52, and spreads easily, The molten conductor 5a is easily guided to the inside of the suction hole 51 through the conductive layer 52 .

Moreover, the back surface electrode 53 is arrange|positioned on the back surface 2b of the insulated substrate 2 so that it may connect with the conductive layer 52 formed in the inner wall surface of the suction hole 51. As shown in FIG. As shown in FIG. 12 , the back electrode 53 is connected to the conductive layer 52 . It is preferable that the surface of the back surface electrode 53 and the surface of the conductive layer 52 exist in the same plane. The back electrode 53 and the conductive layer 52 may be integrated. Thereby, when the soluble conductor 5 melts, the molten conductor 5a which moved from the surface 2a of the insulated substrate 2 to the back surface 2b via the suction hole 51 will be on the back electrode 53 to aggregate in Therefore, in the protection element 50, the molten conductor 5a gets wet on the surface of the back surface electrode 53 and the surface of the conductive layer 52, and it becomes easy to diffuse. Moreover, since more molten conductor 5a is attract|sucked by the suction hole 51, the volume of the molten conductor 5a reduces more in the place where the soluble conductor 5 was cut by fusion.

In addition, in the protection element 50, the heat generating body 3 may be arrange|positioned inside the front surface 2a, the back surface 2b of the insulated substrate 2, or the insulated substrate 2, and may be formed.

When the heating element 3 is arranged and formed on the back surface 2b of the insulating substrate 2, one end of the heating element 3 is connected to the back electrode 53, and the conductive layer 52 and the heating element extraction electrode ( It is electrically connected to the soluble conductor 5 through 4). Moreover, the other end of the heat generating body 3 is connected to the 2nd heat generating body electrode 16 arrange|positioned on the back surface 2b. Similarly, when the heating element 3 is arranged and formed inside the insulating substrate 2, one end of the heating element 3 is connected to the soluble conductor 5 through the first heating element electrode 15 and the heating element extraction electrode 4 and While being electrically connected, the other end of the heat generating body 3 is connected with the 2nd heat generating body electrode 16. As shown in FIG.

When the heating element 3 is disposed on the back surface 2b of the insulating substrate 2, in the protection element 50, the back electrode 53 is heated by the heating element 3, so more molten conductors 5a ) becomes easy to aggregate. Therefore, in the protection element 50, since the molten conductor 5a becomes easy to move from the heat generating body lead-out electrode 4 to the back electrode 53 through the conductive layer 52, in the suction hole 51, a molten conductor (5a) The suction action is promoted. Thereby, the soluble conductor 5 becomes easy to cut by melting.

Moreover, if the heat generating body 3 is arrange|positioned inside the insulated substrate 2, in the protection element 50, the heat generating body lead-out electrode 4 and the back electrode 53 are the heat generating body 3 through the conductive layer 52. ), so that more molten conductors 5a are easily aggregated. Therefore, in the protection element 50, since the molten conductor 5a becomes easy to move from the heat generating body lead-out electrode 4 to the back electrode 53 through the conductive layer 52, in the suction hole 51, a molten conductor (5a) The suction action is promoted. Thereby, the soluble conductor 5 becomes easy to cut by melting.

Moreover, in the protection element 50, in the inside of the suction hole 51, melting|fusing point is lower than the forming material of the material of the same or similar to the forming material of the soluble conductor 5, or the soluble conductor 5, the preliminary solder 55 (55). Alternatively, a flux or the like may be charged. In the protection element 50, when the heating element 3 generates heat, the temperature of the conductive layer 52 excellent in thermal conduction, the heating element extraction electrode 4, and the back electrode 53 is higher than the temperature of the insulating substrate 2 rises Thereby, since the preliminary|backup solder 55 etc. melt|melt before the soluble conductor 5, the molten conductor 5a is drawn into the suction hole 51. As shown in FIG. Therefore, since the molten conductor 5a moves from the front surface 2a of the insulated substrate 2 to the back surface 2b, irrespective of the direction of the protection element 50, the 1st electrode 11 and the 2nd electrode The current path between (12) is easily cut off.

Here, the problems in the case of not using the protection element of one embodiment of the present invention described above are as follows.

The protection element 100 of the reference example with respect to the protection element 1 of this invention, as shown to FIG. 14 and FIG. 15, the insulating substrate 103, the 1st electrode 101, and the 2nd electrode 102, , a heating element 104 , a glass layer 105 , a heating element extraction electrode 106 , a pair of heating element connection electrodes 107a and 107b , a first heating element electrode 108 , and a second heating element electrode 109 . ) and the soluble conductor 110 are provided. The first electrode 101 and the second electrode 102 are connected to an external circuit. The heat generating element 104 is disposed on the insulating substrate 103 and contains a high-melting-point metal such as W, Mo, or Ru. The glass layer 105 insulates and coats the heating element 104 . The heat generating body extraction electrode 106 is electrically connected to the heat generating body 104 while being arrange|positioned so that it may overlap with the heat generating body 104 on the glass layer 105. A pair of heat generating body connection electrodes 107a, 107b are connected with the both ends of the heat generating body 104 in the width direction while being arrange|positioned on the insulating substrate 103. The first heat generating electrode 108 is connected to the heat generating body 104 via the heat generating body connection electrode 107a and connected to the heat generating body lead electrode 106 . The second heating element electrode 109 is connected to the heating element connection electrode 107a, and the heating element 104 is connected to an external power supply circuit. The soluble conductor 110 is connected to the 1st electrode 101 and the 2nd electrode 102 via the heat generating body extraction electrode 106. This soluble conductor 110 is connected with the 1st electrode 101, the 2nd electrode 102, and the heat generating body extraction electrode 106 through connection materials 111, such as solder. In addition, in FIG. 15, the glass layer 105 is abbreviate|omitted.

In the protection element 100, when the 1st electrode 101 and the 2nd electrode 102 are connected to an external circuit, the soluble conductor 110 is attached to the current path of an external circuit. Moreover, in the protection element 100, the soluble conductor 110, the heat generating body extraction electrode 106, the heat generating body 104, and the 2nd from the 1st electrode 101 by the 2nd heat generating body electrode 109 being connected to an external circuit. A power supply path to an external circuit via the heating element electrode 109 , that is, a power supply path to the heating element 104 is formed.

Usually, in the protection element 100, electricity supply with respect to a power supply path|route is regulated by the switch element formed in the external circuit. And, in the case of blocking the current path of the external circuit, in the protection element 100, when the regulation of energization to the power supply path is released by the switch element, since the heating element 104 is energized and generates heat, the soluble conductor ( 110) is fused. As a result, the current path of the external circuit is cut off and the power supply to the heating element 104 is also stopped.

In order to respond to large current capacity, in the protection element 100, resistance reduction of the soluble conductor 110 is aimed at by increasing the cross-sectional area of the soluble conductor 110. Here, when the cross-sectional area of the soluble conductor 110 is increased in order to respond to a large current, the electric power required in order to cut the soluble conductor 110 by melting using heat of the heat generating body 104 will also increase.

However, the protection element used for the use with comparatively low electric current capacity WHEREIN: When the soluble conductor 110 is enlarged and a large current is passed through the soluble conductor 110, the thermal shock to the insulated substrate 103 will be excessive. Therefore, in the place where the heat generating body 104 is arrange|positioned, the insulating substrate 103 becomes easy to crack. In the insulating substrate 103, the closer to the outer edge portion, the higher the cooling effect by heat dissipation, and since it becomes the highest temperature in the central portion, when the heat generating element 104 is formed in the central portion, the stress accompanying thermal expansion is reduced. get bigger Moreover, in the protection element 100, since the soluble conductor 110 is being fixed to the heat generating body lead-out electrode 106 superimposed on the heat generating body 104 through the glass layer 105, in the center part of the insulated substrate 103 The generated stress (strain) affects the operation of the protection element 100 . Since the central part of the insulating substrate 103 becomes easy to crack, and the heat generating body 104 formed in the central part becomes easy to crack, it originates in a power feeding path being interrupted|blocked, heat_generation|fever stops, etc. protection element The operation of (100) may become unstable.

While such a tendency enlarges the soluble conductor 110 in order to improve the rating of the protection element 100, in order to aim at size reduction of the protection element 100, it becomes remarkable, so that the insulated substrate 103 is thinned.

In order to alleviate the thermal shock to such an insulating substrate 103, it is also conceivable to reduce an electric power density by increasing the area of the heat generating body 104, for example. However, when the power density is lowered, it is possible to prevent the insulating substrate 103 and the heating element 104 from being cracked, while the heat transfer efficiency to the fusible conductor 110 is lowered. It becomes difficult to forge.

Example

Next, an embodiment of the present invention will be described. In this embodiment, two heating elements 3 are arranged on the insulating substrate 2, and a protection element 1 ( Example: see Fig. 1) and two heating elements 3 are arranged on an insulating substrate 2 The element 200 (a comparative example: refer FIG. 13) was prepared, and the melting time of the soluble conductor 5 using the heat_generation|fever of the heat generating body 3 was measured.

In the protection element 1 of an Example and the protection element 200 of a comparative example, the ceramic substrate in which the two heat generating elements 3 were arrange|positioned on the surface were used as the insulating substrate 2. Moreover, as the soluble conductor 5 connected to the 1st electrode 11 and the 2nd electrode 12, Ag plating process (6 micrometers in thickness) was given Sn-Ag-Cu system metal foil (thickness 0.35 mm, width 5.4) mm) was used. The soluble conductor 5, the 1st electrode 11, and the 2nd electrode 12 were connected using solder. Moreover, the 1st electrode 11 and the 2nd electrode 12 were supported by the outer casing 10 made from PPS.

With respect to the protection element 1 of an Example and the protection element 200 of a comparative example, the electric power of 32 W and 100 W is applied and the soluble conductor 5 is cut by melting using the heat|fever of the heat generating body 3 by melting. (5) the melting time was measured. In this case, the number of times of measurement (number of samples) was set to 4. Table 1 shows the measurement results.

As shown in Table 1, in the protection element 1 of an Example, even when the applied electric power was 32 W and 100 W, compared with the protection element 200 of a comparative example, fusing time became short. On the other hand, in the protection element 200 of a comparative example, when 100 W electric power was applied, since the insulated substrate 2 cracked in the sample of half, the soluble conductor 5 could not be melt-cut (NG).

This result has shown the following tendency. In the embodiment, the heating element lead-out electrode 4 is disposed so as to overlap the two heating elements 3 . Thereby, since the heat which generate|occur|produced in each heat generating body 3 was easy to transmit efficiently to the heat generating body extraction electrode 4 through the insulating member 13, while the soluble conductor 5 was heated quickly, it fuse|melted. Moreover, in an Example, the heat which generate|occur|produced in the heat generating body 3 becomes easier to transmit to the heat generating body lead-out electrode 4 and the soluble conductor 5. Thereby, even when 100 W electric power was applied, since the thermal shock to the insulated substrate 2 was relieve|moderated, the insulated substrate 2 and the heat generating body 3 became difficult to crack.

On the other hand, in the comparative example, the heat generating element lead-out electrode 4 is arrange|positioned so that it may not overlap with the two heat generating elements 3 . Accordingly, the heat generated in each heating element 3 is not transmitted to the heating element extraction electrode 4 efficiently, that is, the heat conduction efficiency from the heating element 3 to the heating element extraction electrode 4 is low. The melting time was longer than that of Moreover, in the comparative example, the heat which generate|occur|produced in the heat generating body 3 becomes easy to accumulate|store in the insulated substrate 2 . Thereby, since the thermal shock with respect to the insulated substrate 2 becomes excessive when 100 W electric power is applied, while the insulated substrate 2 is cracked in half of the samples, the soluble conductor 5 is melted It didn't happen.

From this, while a plurality of heating elements are arranged on the insulating substrate, the protection element in which the heating element extraction electrode is arranged so as to partially overlap with each heating element rapidly cuts a soluble conductor by melting and alleviation of thermal shock to the insulating substrate It is effective in securing stable heat generation operation using

This application claims priority on the basis of Japanese Patent Application No. 2014-110513 for which it applied on May 28, 2014 by the Japan Patent Office, All content of this application is used for this application by reference. .

Various modifications, combinations, sub-combinations, and changes can be envisaged by those skilled in the art according to design requirements or other factors, but it is understood that they are included within the spirit of the appended claims and their equivalents. .

1: protection element
2: Insulation substrate
3: heating element
4: heating element extraction electrode
5: fusible conductor
7: connection material
10: outer casing
11: first electrode
12: second electrode
13: insulation member
15: first heating element electrode
16: second heating element electrode
17: heating element connection electrode
20: through hole
30: battery pack
1 to 34: battery cell
35: battery stack
36: detection circuit
37: current control element
40: charge and discharge control circuit
41, 42: current control element
43: control unit
45: charging device
50: protection element
51: suction hole
52: conductive layer
53: back electrode
55: spare solder

Claims (9)

an insulated substrate;
a plurality of heating elements disposed and formed on the insulating substrate;
a heating element lead-out electrode electrically connected to each of the plurality of heating elements;
A soluble conductor supported by the heating element extraction electrode is provided;
The plurality of heating elements are arranged and formed on both sides of the boundary with the center of the insulating substrate as a boundary, and are electrically insulated from each other through an insulating member,
The said heating-element extraction electrode is arrange|positioned and formed in the area|region extending from the center of the said insulating substrate to the both sides, the protection element. The method of claim 1,
The said heating-element lead-out electrode is arrange|positioned and formed so that it may partially overlap with respect to each of the said several heating element, The protection element. The method of claim 1,
The soluble conductor extends in a predetermined direction,
Each of the plurality of heat generating elements has a rectangular planar shape having a longitudinal direction in a direction intersecting the extension direction of the soluble conductor,
One end of each of the plurality of heating elements in the longitudinal direction is connected to the heating element lead-out electrode,
The protection element, wherein each other end of each of the plurality of heat generating elements in the longitudinal direction is connected to an external connection electrode. The method of claim 1,
The soluble conductor extends in a predetermined direction,
In one side of the plurality of heat generating elements in a direction crossing the extending direction of the soluble conductor, external connection electrodes are arranged and formed so as to face each of the plurality of heat generating elements,
The protection element wherein the insulating substrate is fixed to an external circuit via the external connection electrode in a region where the plurality of heating elements are not arranged. 5. The method of claim 4,
The plurality of heating elements are disposed and formed on the surface of the insulating substrate,
A connection terminal part is arranged and formed on the back surface opposite to the front surface of the insulating substrate,
the external connection electrode is connected to the connection terminal part through a conductive through hole formed in the insulating substrate;
The said connection terminal part is a protection element connected to the said external circuit. 5. The method of claim 4,
The plurality of heating elements are disposed and formed on the surface of the insulating substrate,
Solder bridges are arranged and formed from the front surface of the insulating substrate to the rear surface on the opposite side;
and the external connection electrode is connected to the external circuit via the solder bridge. The method of claim 1,
The insulating substrate has a suction hole in the thickness direction,
The said suction hole is a protection element which attracts|sucks the molten conductor which is the melt of the said soluble conductor. one or more battery cells;
a protection element connected to the one or more battery cells so as to be able to block the current flowing in the one or more battery cells;
a current control element for controlling a current for heating the protection element while detecting a voltage value of each of the one or more battery cells;
The protection element is
an insulated substrate;
a plurality of heating elements disposed and formed on the insulating substrate;
a heating element lead-out electrode electrically connected to each of the plurality of heating elements;
A soluble conductor supported by the heating element extraction electrode is provided;
The plurality of heating elements are arranged and formed on both sides of the boundary with the center of the insulating substrate as a boundary, and are electrically insulated from each other through an insulating member,
The said heating element extraction electrode is arrange|positioned and formed in the area|region extending from the center of the said insulating board|substrate to both sides, the battery pack. delete

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