KR102251913B1 - Protective element and battery pack - Google Patents

Abstract

While securing the current capacity during overcurrent protection, it is reliably melted by the heat generated by the heating element. The first insulating substrate 55, the first and second external electrodes 51 and 52, the heating element 57 formed on the rear surface 55b side of the first insulating substrate 55, and the first insulating substrate 55 ) So that the front and back electrodes 56 and 64 formed between the first external electrode 51 and the second external electrode 52 of the surface 55a, and the surface 55a overlap the surface electrode 56, A fusible conductor 53 laminated over the first and second external electrodes 51 and 52, a through hole 58 in which a conductive layer 65 is formed on the inner side, and a preliminary solder filled in the through hole 58 It is equipped with (66). By the heat of the heating element 57, the preliminary solder 66 and the soluble conductor 53 are melted, and the temperature of the front and back electrodes 56 and 64, the wetting properties of the conductive layer 65 in the through hole 58, etc. The molten preliminary solder 66 and the fusible conductor 53 move to the rear surface 55b side of the first insulating substrate 55 having a higher value.

Description

Protection element and battery pack {PROTECTIVE ELEMENT AND BATTERY PACK}

The present invention relates to a protection element and a battery pack for protecting a circuit connected on a current path by melting the current path. This application has priority based on Japanese Patent Application No. Japanese Patent Application No. 2013-163950 filed on August 7, 2013 in Japan, and Japanese Patent Application No. Japanese Patent Application No. 2014-113044 filed May 30, 2014 in Japan. Claims, and these applications are incorporated herein by reference.

Many of the secondary batteries that can be charged and used repeatedly are processed into a battery pack and provided to a user. In particular, in lithium-ion secondary batteries having a high weight energy density, in order to ensure the safety of users and electronic devices, in general, several protection circuits, such as overcharge protection and overdischarge protection, are built into the battery pack. It has a function to cut off the output of the battery pack.

In electronic devices using many lithium-ion secondary batteries, the overcharge protection or overdischarge protection operation of the battery pack is performed by turning on/off the output using a FET switch built into the battery pack. However, even if the FET switch is short-circuited or destroyed for some reason, a lightning surge, etc. is applied and an instantaneous large current flows, or the output voltage abnormally decreases due to the life of the battery cell, or conversely, an excessive voltage is output , Battery packs and electronic devices must be protected from accidents such as fire. Therefore, in order to safely cut off the output of the battery cell in any possible abnormal state as described above, a protection element made of a fuse element having a function of blocking a current path by an external signal is used.

As a protection element for a protection circuit for such a lithium ion secondary battery, as described in Patent Document 1, a structure in which a heating element is provided inside the protection element, and the soluble conductor on the current path is blown by the heat generated by the heating element. It is generally used.

Japanese Unexamined Patent Publication No. 2010-3665

In the protection element described in Patent Literature 1, in order to be used in applications with a relatively low current capacity, such as a mobile phone or a notebook PC, the soluble conductor (fuse) has a current capacity of up to about 15 A. The use of lithium-ion secondary batteries is expanding in recent years, and applications for higher currents, such as power tools such as electric drivers, and transportation devices such as hybrid cars, electric vehicles, and electric assist bicycles, are being considered, and some adoptions are being made. It is being disclosed. In such applications, particularly at start-up, there is a case where a large current exceeding several tens A to 100 A flows. It is desired to realize a protection element corresponding to such a large current capacity.

In order to realize a protection element corresponding to a large current, it is sufficient to increase the cross-sectional area of the usable conductor. However, the protection element needs to detect the overvoltage condition of the battery cell, pass a current through the heating element formed of the resistor, and cut the soluble conductor by the heat generation, in addition to the case of melting due to the overcurrent condition. If the cross-sectional area is increased in order to cope with a large current, the melting amount of the soluble conductor at the time of melting increases, and it becomes difficult to stably melt the soluble conductor. In addition, when the melting amount of the soluble conductor increases, the amount of molten conductor aggregates increases immediately before the current interruption due to overcurrent, and the molten conductor scatters in a large amount due to arc discharge at the time of interruption, reducing the insulation resistance and mounting the soluble conductor. The risk of a short circuit of the peripheral circuit of the location is also increased. In addition, it is also a problem that the fusing operation varies depending on the posture in which the protection element is disposed.

Accordingly, an object of the present invention is to obtain a protection element and a battery pack capable of suppressing scattering of a molten conductor due to arc discharge when the current is cut off by an overcurrent while securing the current capacity during overcurrent protection. Another object of the present invention is to obtain a protection element and a battery pack capable of reliably melting a fusible conductor by heat generated by a heating element while securing a current capacity during overcurrent protection.

The protection element according to the present invention for solving the above-described problem has a first insulating substrate and a soluble conductor mounted on a surface of the first insulating substrate, and the soluble conductor is melted on the surface of the first insulating substrate. A suction hole for suctioning is opened.

In addition, the battery pack according to the present invention includes at least one battery cell, and a protection element connected on a charge/discharge path of the battery cell and blocks the charge/discharge path, wherein the protection element is a first insulation It has a substrate and a soluble conductor mounted on a surface of the first insulating substrate and serving as the charge/discharge path, and a suction hole for sucking the molten soluble conductor is opened on the surface of the first insulating substrate.

In addition, the protection element according to the present invention sucks the first and second external electrodes, a soluble conductor connected between the first and second external electrodes, and the soluble conductor connected to the soluble conductor and melted. A first insulating substrate disposed between the first and second external electrodes, and a surface electrode formed on a surface of the first insulating substrate and connected to a part of the soluble conductor And, a heating element formed on the first insulating substrate, a through hole formed in a thickness direction of the first insulating substrate, and a through hole continuous with the surface electrode, and the soluble conductor is melted to form the first external electrode and the first insulating substrate. 2 It blocks the current path between the external electrodes.

In addition, the battery pack according to the present invention includes at least one battery cell, a protection element connected on a charge/discharge path of the battery cell, and a protection element blocking the charge/discharge path, and a voltage value of the battery cell is detected. A current control element for controlling energization to the protection element is provided, wherein the protection element includes a first and second external electrodes, a soluble conductor connected between the first and second external electrodes, and the molten soluble It has a suction member for suctioning a conductor, wherein the suction member is formed on a first insulating substrate disposed between the first and second external electrodes and formed on a surface of the first insulating substrate, and is connected to a part of the soluble conductor. The first external electrode is provided with a formed surface electrode, a heating element formed on the first insulating substrate, a through hole formed in the thickness direction of the first insulating substrate and continuous with the surface electrode, and the soluble conductor is melted. The current path between the and the second external electrode is blocked.

In addition, the protection element according to the present invention for solving the above-described problem includes a first insulating substrate, a first and second external electrodes, and the first external electrode on one side of the first insulating substrate. The first and second intermediate electrodes formed between the second external electrodes, a heating element formed on the other side of the first insulating substrate, and connected to the intermediate electrode on one surface of the first insulating substrate A soluble conductor that is connected across the external electrode and cuts a current path between the first external electrode and the second external electrode by heating by the heating element, and is formed on the other side of the first insulating substrate, The heating element lead electrode electrically connected to one terminal of the heating element, and the intermediate electrode and the heating element lead electrode are formed in the thickness direction of the first insulating substrate between the intermediate electrode and the heating element lead electrode, and the intermediate electrode and the heating element lead electrode are formed on an inner surface thereof. It has a through hole in which a continuous conductive layer is formed.

The battery pack according to the present invention includes at least one battery cell, a protection element connected to block a current flowing through the battery cells, and a current control element that controls a current heating the protection element by detecting a voltage value of each of the battery cells. It is equipped with. In addition, the protection element includes a first insulating substrate, a first and second external electrodes, an intermediate electrode formed between the first external electrode and the second external electrode on one surface side of the first insulating substrate, and , A heating element formed on the other surface side of the first insulating substrate, and connected to the intermediate electrode on one surface of the first insulating substrate and connected across the first and second external electrodes, by the heating element By heating, a fusible conductor that fuses the current path between the first external electrode and the second external electrode, is formed on the other side of the first insulating substrate, and is electrically connected to one terminal of the heating element. A through-hole formed in the thickness direction of the first insulating substrate between the heating element lead electrode and the intermediate electrode and the heating element lead electrode, and in which a conductive layer continuous with the intermediate electrode and the heating element lead electrode is formed on an inner surface. .

According to the present invention, when the soluble conductor is melted, the molten soluble conductor is drawn into the suction hole formed in the first insulating substrate, so that even when a large amount of the molten conductor is generated, it is reliably melted. Therefore, even when the cross-sectional area of the usable conductor is increased in order to improve the rating, the current path can be reliably cut.

1 is a cross-sectional view showing a protection element to which the present invention is applied.
Fig. 2 is a cross-sectional view showing a state in which a molten conductor is sucked in a protection element to which the present invention is applied.
3 is a cross-sectional view showing a state in which a soluble conductor is melted in the protection element to which the present invention is applied.
4 is a block diagram showing a configuration example of a battery pack in which a protection element is used.
5 is a circuit diagram of a protection element to which the present invention is applied.
6 is a cross-sectional view showing a protection element provided with a heat generating element on the surface side of a first insulating substrate.
7 is a cross-sectional view showing a protection element provided with a heat generating element on the back side of the first insulating substrate.
8 is a cross-sectional view showing a protection element including a heat generating element in a first insulating substrate.
9 is a block diagram showing a configuration example of a battery pack in which a protection element is used.
10 is a circuit diagram of a protection element to which the present invention is applied.
Fig. 11(A) is a plan view of a protection element to which the present invention is applied. Fig. 11(B) is a cross-sectional view taken along line AA' in Fig. 11(A).
12 is a block diagram showing an application example of a protection element to which the present invention is applied.
13 is a diagram showing an example of a circuit configuration of a protection element to which the present invention is applied.
Fig. 14A is a cross-sectional view showing an operation of the heating element of the protection element to which the present invention is applied. 14(B) is a cross-sectional view showing a state in which a soluble conductor is melted.
15(A)-(E) are diagrams showing a posture of a usage mode of the protection element to which the present invention is applied.
Fig. 16 is a diagram showing the melting time of the soluble conductor in each posture of Figs. 15(A)-(E).
Fig. 17(A) is a plan view of a cohesive protection element serving as a reference example, and Fig. 17(B) is a cross-sectional view taken along line AA' in Fig. 17(A). Fig. 17(C) is a cross-sectional view of a melted state.
18(A)-(E) are diagrams showing postures in a usage mode of the protection element of the reference example shown in FIG. 17.
Fig. 19 is a diagram showing the melting time of the soluble conductor in each posture of Figs. 18(A)-(E).
Fig. 20 is a diagram showing a modified example of through-holes formed in the intermediate electrode of the first insulating substrate, (A) shows an example in which through-holes are formed in two rows, and (B) is a through-hole as a slit Here is an example.
21 is a cross-sectional view showing a protection element provided with a heat generating element on the surface side of the first insulating substrate.
22(A)-(E) are diagrams showing a posture of a usage mode of the protection element to which the present invention is applied.
Fig. 23 is a diagram showing the melting time of the soluble conductor in each posture of Figs. 22(A)-(E).
Fig. 24 is a cross-sectional view showing a protection element provided with an agglomeration member, where (A) shows before melting of the soluble conductor, and (B) shows after melting of the soluble conductor.
25 is a circuit diagram showing a protection element provided with a cohesive member.
Fig. 26 is a cross-sectional view showing a protection element provided with a plurality of suction members, where (A) shows before melting of the soluble conductor and (B) after melting of the soluble conductor.
27 is a circuit diagram showing a protection element including a plurality of suction members.
Fig. 28 is a perspective view showing a soluble conductor having a high melting point metal layer and a low melting point metal layer, and having a covering structure, (A) shows a structure in which a high melting point metal layer is used as an inner layer and is coated with a low melting point metal layer, (B) Represents a structure in which a low melting point metal layer is used as an inner layer and a high melting point metal layer is coated.
Fig. 29 is a perspective view showing a soluble conductor having a laminated structure of a high-melting-point metal layer and a low-melting-point metal layer, where (A) shows a two-layer structure, and (B) shows a three-layer structure of an inner layer and an outer layer.
Fig. 30 is a cross-sectional view showing a soluble conductor having a multilayer structure of a high melting point metal layer and a low melting point metal layer.
31 is a plan view showing a soluble conductor in which a linear opening is formed on the surface of a high melting point metal layer to expose the low melting point metal layer, (A) is an opening formed along the length direction, and (B) is a width direction. Thus, an opening is formed.
Fig. 32 is a plan view showing a soluble conductor in which a circular opening is formed on the surface of the high melting point metal layer to expose the low melting point metal layer.
33 is a plan view showing a soluble conductor in which a circular opening is formed in a high melting point metal layer and a low melting point metal is filled therein.
Fig. 34 is a plan view showing a soluble conductor in which a thick first side edge portion is coated on a high melting point metal and a second side edge portion is exposed to the low melting point metal.

Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the drawings. In addition, the present invention is not limited only to the following embodiments, and it goes without saying that various changes can be made within the scope not departing from the gist of the present invention.

[First Embodiment]

The protection element 1 to which the present invention was applied has a first insulating substrate 10 and a soluble conductor 13 mounted on the surface 10a of the first insulating substrate 10 as shown in FIG. 1, A suction hole 20 for sucking the molten soluble conductor 13 is opened in the surface 10a of the first insulating substrate 10. And the protection element 1 is attached to an external circuit so that the soluble conductor 13 forms part of the current path of the said external circuit, and cuts off a current path by melting|fusing by an overcurrent exceeding a rating.

The first insulating substrate 10 is formed in a square shape by a member having insulating properties such as alumina, glass ceramics, mullite, and zirconia. In addition, as the first insulating substrate 10, a material used for a printed wiring board such as a glass epoxy substrate and a phenol substrate may be used.

First and second electrodes 11 and 12 are formed at opposite ends of the surface 10a of the first insulating substrate 10 that face each other. Each of the first and second electrodes 11 and 12 is formed by a conductive pattern such as Cu wiring, and a protective layer such as Sn plating is formed on the surface as an appropriate anti-oxidation countermeasure. Further, the first and second electrodes 11 and 12 are formed on the rear surface 10b through the conductive layers 11b and 12b reaching the rear surface 10b through the side surfaces of the first insulating substrate 10. It is connected to the 1st and 2nd external connection electrodes 11a, 12a. The protection element 1 is connected on the current path of the circuit board by connecting the first and second external connection electrodes 11a and 12a to a circuit board constituting an external circuit. And, in the protection element 1, the soluble conductor 13, which will be described later, is mounted between the first and second electrodes 11, 12, so that the soluble conductor 13 is connected to the first and second external connection electrodes 11a. , 12a) becomes a part of the current path of the circuit board.

Further, the first insulating substrate 10 has suction holes 20 formed between the first and second electrodes 11 and 12. The suction hole 20 is to reduce the volume of the molten conductor 13a by sucking the molten conductor 13a by capillary phenomenon when the soluble conductor 13 is melted by self-heating due to an overcurrent (Fig. 2). The protection element 1 increases the cross-sectional area of the soluble conductor 13 in order to cope with the use of a high current, thereby reducing the volume of the molten conductor 13a by being sucked into the suction hole 20 even when the amount of melt is increased. I can. Thereby, the protection element 1 reduces scattering of the molten conductor 13a due to arc discharge at the time of interruption, prevents a decrease in insulation resistance, and also prevents the soluble conductor 13 from being mounted to the peripheral circuit at the mounting position. Short circuit failure due to attachment can be prevented.

The suction hole 20 has a conductive layer 21 formed on the inner surface thereof. When the conductive layer 21 is formed, the suction hole 20 can easily suck the molten conductor 13a. The conductive layer 21 is formed of, for example, copper, silver, gold, iron, nickel, palladium, lead, tin, or an alloy containing as a main component, and the inner surface of the suction hole 20 is electrolyzed. It can be formed by a known method such as plating or printing of a conductive paste. Further, the conductive layer 21 may be formed by inserting an assembly of a plurality of metal wires or a conductive ribbon into the suction hole 20.

In addition, the suction hole 20 is preferably formed as a through hole penetrating in the thickness direction of the first insulating substrate 10. Thereby, the suction hole 20 can suck the molten conductor 13a up to the rear surface 10b side of the first insulating substrate 10, and attract more molten conductors 13a in the melting portion. The volume of the molten conductor 13a can be reduced. Further, the suction hole 20 may be formed as a non-penetrating hole.

A surface electrode 22 connected to the conductive layer 21 of the suction hole 20 is formed on the surface 10a of the first insulating substrate 10. The surface electrode 22 becomes a support electrode to which the soluble conductor 13 is connected. Moreover, since the surface electrode 22 is continuous with the conductive layer 21, when the soluble conductor 13 is melted, the molten conductor 13a is agglomerated and easily guided into the suction hole 20.

Further, on the back surface 10b of the first insulating substrate 10, a back electrode 23 connected to the conductive layer 21 of the suction hole 20 is formed. The back electrode 23 is continuous with the conductive layer 21, so that when the soluble conductor 13 is melted, the molten conductor 13a that has moved through the suction hole 20 is aggregated (see FIG. 3 ). Thereby, the protection element 1 can suck more molten conductor 13a, and can reduce the volume of the molten conductor 13a in a melting|fusing part.

In addition, the protective element 1 increases the path for sucking the molten conductor 13a of the soluble conductor 13 by forming a plurality of suction holes 20, and attracts more molten conductors 13a, whereby the melting portion You may try to reduce the volume of the molten conductor 13a in.

Next, the soluble conductor 13 will be described. The fusible conductor 13 is mounted across the first and second electrodes 11 and 12, and is fused by self-heating (Joule heat) when a current exceeding the rating is energized. The current path between the two electrodes 12 is cut off.

The soluble conductor 13 may be a conductive material melted by an overcurrent state, for example, in addition to SnAgCu-based Pb-free solder, BiPbSn alloy, BiPb alloy, BiSn alloy, SnPb alloy, PbIn alloy, ZnAl alloy, InSn Alloys, PbAgSn alloys, and the like can be used.

Moreover, the soluble conductor 13 may be a structure containing a high melting point metal and a low melting point metal. For example, as shown in FIG. 1, the soluble conductor 13 is a laminated structure composed of an inner layer and an outer layer, a low melting point metal layer 13b as an inner layer, and a high melting point metal layer as an outer layer laminated on the low melting point metal layer 13b. (13c) has. The soluble conductor 13 is connected to the first and second electrodes 11 and 12 and the surface electrode 22 via a bonding material such as solder.

The low melting point metal layer 13b is preferably a metal containing solder or Sn as a main component, and is a material generally referred to as "Pb-free solder" (for example, manufactured by Senju Metal Industries, M705, etc.). The melting point of the low melting point metal layer 13b is not necessarily higher than the reflow temperature, and may be melted at about 200°C. The high melting point metal layer 13c is a metal layer laminated on the surface of the low melting point metal layer 13b, and is, for example, Ag or Cu, or a metal containing any of these as a main component, and the protection element 1 is reflowed. Therefore, it has a high melting point that does not melt even when mounting on an external circuit board.

Such a soluble conductor 13 can be formed by depositing a high-melting-point metal layer on a low-melting-point metal foil using a plating technique, or can be formed using other well-known lamination techniques and film-forming techniques. In addition, the soluble conductor 13 may be constituted with a high melting point metal layer as an inner layer and a low melting point metal layer as an outer layer, and a multilayer structure of four or more layers in which a low melting point metal layer and a high melting point metal layer are alternately stacked, etc., As described later, it can be formed by various configurations.

The soluble conductor 13 is soluble even when the reflow temperature exceeds the melting temperature of the low melting point metal layer 13b by laminating the high melting point metal layer 13c as the outer layer on the low melting point metal layer 13b serving as the inner layer. It does not lead to melting as the conductor (13). Therefore, the protection element 1 can be mounted efficiently by reflow.

Further, the fusible conductor 13 is not melted even by self-heating while a predetermined rated current is flowing. Then, when a current of a higher value than the rated value flows, it is melted by self-heating, thereby blocking the current path between the first and second electrodes 11 and 12. At this time, the soluble conductor 13 is melted at a temperature lower than the melting temperature of the high melting point metal layer 13c by the molten low melting point metal layer 13b eroding the high melting point metal layer 13c. Therefore, the soluble conductor 13 can be melted in a short time by utilizing the erosion action of the high melting point metal layer 13c by the low melting point metal layer 13b. In addition, the molten conductor 13a of the soluble conductor 13 is physically applied to the surface electrode 22 and the first and second electrodes 11 and 12 in addition to the suction action by the suction hole 20 described above. Since it is divided by the pull-in action, it is possible to quickly and reliably cut off the current path between the first and second electrodes 11 and 12.

In addition, since the soluble conductor 13 is constructed by laminating a high melting point metal layer 13c on a low melting point metal layer 13b serving as an inner layer, the melting temperature can be significantly reduced compared to a conventional chip fuse made of a high melting point metal. I can. Accordingly, the fusible conductor 13 can have a larger cross-sectional area than that of a chip fuse of the same size, and the current rating can be significantly improved. Further, it is possible to achieve a smaller size and a thinner thickness than that of a conventional chip fuse having the same current rating, and it is excellent in fast-melting property.

Further, the soluble conductor 13 can improve resistance to surges (pulse resistance) in which an abnormally high voltage is instantaneously applied to the electric system in which the protection element 1 is mounted. That is, the soluble conductor 13 should not be melted until, for example, a current of 100 A flows for several msec. In this respect, since the high current flowing in an extremely short time flows through the surface layer of the conductor (skin effect), the soluble conductor 13 has a high melting point metal layer 13c such as Ag plating having a low resistance value as an outer layer. , It is easy to flow the current applied by the surge, so that melting due to self-heating can be prevented. Therefore, the fusible conductor 13 can significantly improve the resistance to surge as compared to a fuse made of a conventional solder alloy.

Further, the soluble conductor 13 is coated with a flux 14 in order to prevent oxidation and improve wettability during melting. In addition, the inside of the protection element 1 is protected by covering the first insulating substrate 10 with the cover member 15. The cover member 15 can be formed using, for example, a member having insulating properties such as a thermoplastic plastic, ceramics, or glass epoxy substrate, similarly to the first insulating substrate 10.

[Circuit composition]

As shown in FIG. 4, such a protection element 1 is attached to the circuit in the battery pack 30 of a lithium ion secondary battery, and is used, for example. The battery pack 30 has, for example, a battery stack 35 composed of battery cells 31 to 34 of a total of four lithium ion secondary batteries.

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 the present invention for blocking charging when the battery stack 35 is abnormal. A protection element 1 and a detection circuit 36 for detecting the voltage of each of the battery cells 31 to 34 are provided.

In the battery stack 35, battery cells 31 to 34 that need control for protection from overcharge and overdischarge conditions are connected in series, and the positive electrode terminal 30a and the negative electrode terminal 30b of the battery pack 30 ) Is connected to the charging device 45 so as to be detachably attached, and a charging voltage from the charging device 45 is applied. This electronic device can be operated by connecting the positive electrode terminal 30a and the negative electrode terminal 30b of the battery pack 30 charged by the charging device 45 to an electronic device operated by a battery.

The charge/discharge control circuit 40 includes two current control elements 41 and 42 serially connected to a current path flowing from the battery stack 35 to the charging device 45, and the current control elements 41 and 42. And a control unit 43 that controls the operation. The current control elements 41 and 42 are constituted by, for example, field effect transistors (hereinafter referred to as FETs), and by controlling the gate voltage by the control unit 43, the current path of the battery stack 35 is conducted. And cut off control. The control unit 43 operates by receiving electric power from the charging device 45, and according to the detection result by the detection circuit 36, when the battery stack 35 is overdischarged or overcharged, the current path is cut off, Controls the operation of the current control elements 41 and 42.

The protection element 1 is connected on the charge/discharge current path between the battery stack 35 and the charge/discharge control circuit 40, for example.

The detection circuit 36 is connected to each battery cell 31 to 34, detects the voltage value of each battery cell 31 to 34, and converts each voltage value to the control unit 43 of the charge/discharge control circuit 40 To supply.

The protection element 1 to which the present invention is applied, which is used in the battery pack 30 configured as described above, has a circuit configuration as shown in FIG. 5. That is, in the protection element 1, the first external connection electrode 11a is connected to the battery stack 35 side, and the second external connection electrode 12a is connected to the positive electrode terminal 30a side, whereby the soluble conductor 13 is connected in series on the charge/discharge path of the battery stack 35.

[Operation of protection element]

When an overcurrent exceeding the rating is applied to the battery pack 30, the protective element 1 causes the fusible conductor 13 to melt due to self-heating, thereby blocking the charging/discharging path of the battery pack 30. At this time, as shown in Figs. 2 and 3, the protection element 1 uses a high current because the molten conductor 13a is sucked into the suction hole 20 through the surface electrode 22 by capillary phenomenon. Even when the cross-sectional area of the soluble conductor 13 is increased in order to cope with this, the volume of the molten conductor 13a at the time of blocking can be reduced, and scattering of the molten conductor 13a due to arc discharge can be reduced. In addition, the protective element 1 is formed by forming the soluble conductor 13 by containing a high melting point metal and a low melting point metal, so that the low melting point metal is melted before the melting of the high melting point metal, thereby efficiently attracting the soluble conductor 13 It can be sucked into the ball (20).

In addition, the protection element 1 according to the present invention is not limited to the case of being used for a battery pack of a lithium ion secondary battery, and can of course also be applied to various uses requiring interruption of a current path due to an overcurrent.

[Heating element]

Moreover, as shown in FIG. 6, the protection element to which this invention was applied may form the heat generating element 25 which melt|dissolves the soluble conductor 13 in the 1st insulating substrate 10. In the following description, the same reference numerals are given to the same members as those of the protection element 1 described above, and details thereof are omitted.

The protection element 24 in which the heating element 25 is formed, for example, when attached to the battery pack, detects the overvoltage of the battery cell in addition to the self-melting of the soluble conductor 13 at the time of an overcurrent, so that the heating element 25 is The charging/discharging path of the battery pack can be cut off by energizing, heating, and melting the fusible conductor 13.

The heating element 25 is a member having a relatively high resistance value and a conductive member that generates heat when energized, and is made of, for example, W, Mo, Ru, or the like. These alloys, compositions, and powders of a compound are mixed with a resin binder or the like to form a paste, and a pattern is formed on the surface 10a of the first insulating substrate 10 using a screen printing technique, It is formed by firing or the like.

The heat generating element 25 is covered with the insulating layer 26 on the surface 10a of the first insulating substrate 10. On the insulating layer 26, a surface electrode 22 is laminated. The insulating layer 26 is formed to protect and insulate the heating element 25 and efficiently transfer the heat of the heating element 25 to the surface electrode 22 and the soluble conductor 13, for example It consists of a layer of glass. When the surface electrode 22 is heated by the heating element 25, the molten conductor 13a of the soluble conductor 13 can be easily agglomerated and easily sucked into the suction hole 20.

The heating element 25 has one end connected to the surface electrode 22 and is electrically connected to the soluble conductor 13 mounted on the surface electrode 22 via the surface electrode 22. Moreover, the heat generating element 25 is connected to the heat generating element electrode which is not shown at the other end. The heating element electrode is formed on the front surface 10a of the first insulating substrate 10 and is connected to the third external connection electrode 27 (see Fig. 9) formed on the back surface 10b, and this third external connection electrode It is connected to an external circuit via (27). And the protection element 1 is mounted on a circuit board constituting an external circuit, so that the heating element 25 is attached to the power supply path to the heating element 25 formed on the circuit board via the third external connection electrode 27. .

In addition, as shown in FIG. 7, the protection element 24 may form the heat generating element 25 on the back surface 10b of the first insulating substrate 10. The heat generating element 25 is formed on the back surface 10b of the first insulating substrate 10 and is covered with the insulating layer 26 on the back surface 10b. On the insulating layer 26, the back electrode 23 is laminated.

The heating element 25 is a soluble conductor mounted on the surface electrode 22 through the conductive layer 21 and the surface electrode 22 formed in the suction hole 20 and connected to the electrode 23 at one end. (13) is electrically connected. Moreover, the heat generating element 25 is connected to the 3rd external connection electrode 27 through the heat generating element electrode which the other end is not shown.

By forming the heat generating element 25 on the back surface 10b of the first insulating substrate 10, the protection element 24 is formed by heating the back electrode 23 by the heat generating element 25, thereby allowing more molten conductors 13a. It becomes easy to agglomerate. Therefore, the protection element 24 promotes the action of attracting the molten conductor 13a from the front electrode 22 to the back electrode 23 via the conductive layer 21, so that the soluble conductor 13 is reliably removed. It can be fusing.

In addition, as shown in FIG. 8, the protection element 24 may form the heat generating element 25 inside the first insulating substrate 10. In this case, the heating element 25 need not be covered with an insulating layer such as glass. In addition, the heating element 25 has one end connected to the front electrode 22 or the back electrode 23 and is electrically connected to the soluble conductor 13 mounted on the front electrode 22. Moreover, the heat generating element 25 is connected to the 3rd external connection electrode 27 through the heat generating element electrode which the other end is not shown.

By forming the heat generating element 25 inside the first insulating substrate 10, the protective element 24 provides the front electrode 22 and the back electrode 23 to the heat generating element 25 via the conductive layer 21. It becomes easy to aggregate more molten conductor 13a by heating. Therefore, the protection element 24 promotes the action of attracting the molten conductor 13a from the front electrode 22 to the back electrode 23 via the conductive layer 21, so that the soluble conductor 13 is reliably removed. It can be fusing.

In addition, the heating element 25 is formed on both sides of the suction hole 20 in any case formed on the front surface 10a, the rear surface 10b, or the inside of the first insulating substrate 10, the surface electrode ( It is preferable in heating 22) and the back electrode 23, and in coagulating and sucking more molten conductors 13a.

[Circuit composition]

As shown in FIG. 9, such a protection element 24 is attached to the circuit in the battery pack 30 of a lithium ion secondary battery, and is used, for example. In addition, in the following description, the same reference|symbol is attached|subjected to the same member as the battery pack 30 mentioned above, and the detail is abbreviate|omitted.

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 the present invention for blocking charging when the battery stack 35 is abnormal. A protection element 24, a detection circuit 36 for detecting the voltage of each battery cell 31 to 34, and a switch element for controlling the operation of the protection element 24 according to the detection result of the detection circuit 36 are provided. The current control element 37 is provided.

The protection element 24 is connected on the charge/discharge current path between the battery stack 35 and the charge/discharge control circuit 40, for example, and its operation is controlled by the current control element 37.

The detection circuit 36 is connected to each battery cell 31 to 34, detects the voltage value of each battery cell 31 to 34, and converts each voltage value to the control unit 43 of the charge/discharge control circuit 40 To supply. Further, the detection circuit 36 outputs a control signal for controlling the current control element 37 when any one of the battery cells 31 to 34 becomes an overcharge voltage or an overdischarge voltage.

The current control element 37 is configured by, for example, a FET, and the voltage value of the battery cells 31 to 34 exceeds a predetermined overdischarge or overcharge state by a detection signal output from the detection circuit 36. When the voltage is reached, the protection element 24 is operated to control the charging/discharging current path of the battery stack 35 to be cut off irrespective of the switch operation of the current control elements 41 and 42.

The protection element 24 to which the present invention is applied, which is used in the battery pack 30 configured as described above, has a circuit configuration as shown in FIG. 10. That is, in the protection element 24, the first external connection electrode 11a is connected to the battery stack 35 side, and the second external connection electrode 12a is connected to the positive electrode terminal 30a side, whereby the usable conductor 13 is connected in series on the charge/discharge path of the battery stack 35. In addition, in the protection element 24, while the heat generating element 25 is connected to the current control element 37 via the heat generating element electrode and the third external connection electrode 27, the heat generating element 25 is It is connected to the open end. Thereby, the heating element 25 has one end connected to one open end of the soluble conductor 13 and the battery stack 35 via the surface electrode 22, and the other end through the third external connection electrode 27. A power supply path to the heat generating element 25, which is connected to the current control element 37 and the other open end of the battery stack 35, is controlled by the current control element 37, is formed.

[Operation of protection element]

When an overcurrent exceeding the rating is applied to the battery pack 30, the protection element 24 causes the fusible conductor 13 to melt due to self-heating, thereby blocking the charge/discharge path of the battery pack 30. At this time, in the protection element 24, since the molten conductor 13a is sucked into the suction hole 20 through the surface electrode 22 by a capillary phenomenon, the soluble conductor 13 is Even when the cross-sectional area is increased, the volume of the molten conductor 13a at the time of blocking is reduced, and scattering of the molten conductor 13a due to arc discharge can be reduced. In addition, the protective element 24 is formed by making the soluble conductor 13 contain a high melting point metal and a low melting point metal, so that the low melting point metal is melted before the melting of the high melting point metal, thereby efficiently attracting the soluble conductor 13 It can be sucked into the ball (20).

Further, when the detection circuit 36 detects an abnormal voltage of any one of the battery cells 31 to 34, it outputs a cutoff signal to the current control element 37. Then, the current control element 37 controls the current so as to energize the heat generating element 25. In the protection element 24, a current flows from the battery stack 35 to the heating element 25 through the first electrode 11, the fusible conductor 13, and the surface electrode 22, whereby the heating element 25 generates heat. Start. In the protection element 24, the fusible conductor 13 is melted by the heat generated by the heat generating element 25, thereby blocking the charging/discharging path of the battery stack 35.

At this time, in the protection element 24, since the molten conductor 13a is sucked into the suction hole 20 through the surface electrode 22 by a capillary phenomenon, the soluble conductor 13 is Even when the cross-sectional area is increased, the charging/discharging path of the battery pack 30 can be reliably blocked. In addition, the protective element 24 can be melted in a short time by using the melting action of the high melting point metal by the molten low melting point metal by forming the soluble conductor 13 by containing a high melting point metal and a low melting point metal. .

In addition, in the protection element 24, since the soluble conductor 13 is melted, the power supply path to the heat generating element 25 is also blocked, so that the heat generation of the heat generating element 25 is stopped.

The protection element 24 according to the present invention is not limited to the case of being used in a battery pack of a lithium-ion secondary battery, and is of course applicable to various uses requiring interruption of a current path by an electric signal.

[Second Embodiment]

[Configuration of protection element]

Next, a second embodiment will be described. 11(A) and 11(B), the protection element 50 is between the first and second external electrodes 51 and 52 and the first and second external electrodes 51 and 52 The soluble conductor 53 laminated over the soluble conductor 53 and a suction member 54 connected to the soluble conductor 53 to suck the molten conductor 53a of the soluble conductor 53 are provided. The suction member 54 is formed on the insulating substrate 55 disposed between the first and second external electrodes 51 and 52 and the surface 55a of the insulating substrate 55, and the soluble conductor 53 A surface electrode 56 connected to a part, a heat generating element 57 formed on the insulating substrate 55, and a through hole 58 formed in the thickness direction of the insulating substrate 55 and connected to the surface electrode 56 are formed. Equipped. The protection element 50 melts the soluble conductor 53 by heating the heating element 57. At this time, the protection element 50 sucks the molten conductor 53a in which the soluble conductor 53 is melted by the suction member 54, reliably melts the soluble conductor 53, and the first external electrode ( 51) and the current path between the second external electrode 52 is cut off.

The first and second external electrodes 51 and 52 are connection terminals for connecting the protection element 50 to an external circuit, and are connected inside the protection element 50 via a fusible conductor 53. The first and second external electrodes 51 and 52 are arranged and formed over the inside and outside of the protection element 50 by being supported by the outer casing of the protection element 50. In addition, the first and second external electrodes 51 and 52 may be formed on the insulating substrate 55 of the suction member 54, or made of an epoxy resin that is adjacent to or integrated with the insulating substrate 55. It may be formed in an insulating material.

The soluble conductor 53 is melted by the overcurrent state and the heat generation of the heating element 57, and therefore, any conductive material to be melted may be sufficient. For example, in addition to the SnAgCu-based Pb-free solder, a BiPbSn alloy, BiPb alloys, BiSn alloys, SnPb alloys, PbIn alloys, ZnAl alloys, InSn alloys, PbAgSn alloys, and the like can be used. In addition, the soluble conductor 53 may be a laminate of a high melting point metal composed of Ag or Cu, or a metal containing Ag or Cu as a main component, and a low melting point metal such as Pb-free solder containing Sn as a main component. As will be described later, such as a multilayer structure of four or more layers in which a melting point metal layer and a high melting point metal layer are alternately stacked, it can be formed by various configurations.

The insulating substrate 55 is formed of, for example, a member having insulating properties such as alumina, glass ceramics, mullite, and zirconia. In addition, materials used for printed wiring boards such as glass epoxy substrates and phenolic substrates may be used, but it is necessary to pay attention to the temperature at the time of fuse melting.

The heat generating element 57 has a relatively high resistance value and is a conductive member that generates heat when energized, and is made of, for example, W, Mo, Ru, or the like. These alloys, compositions, and powders of compounds are mixed with a resin binder, etc., and a paste-like material is formed by forming a pattern on the back surface 55b of the insulating substrate 55 using a screen printing technique and firing. do. Both ends of the heat generating element 57 are connected to the first and second heat generating element electrodes 59 and 60. The first and second heating element electrodes 59 and 60 are formed on the rear surface 55b of the insulating substrate 55 which is the same as the heating element 57. The first heating element electrode 59 is connected to the soluble conductor 53 via a heating element lead electrode 63 to be described later, and the second heating element electrode 60 is a third external connection electrode 61 (Fig. 12, 13), thereby connecting the heating element 57 to a power source for generating heat.

The heat generating element 57 is covered with an insulating member 62 such as glass, and the heat generating element lead electrode 63 is disposed so as to face the heat generating element 57 through the insulating member 62. The insulating member 62 may be a laminated substrate in which the heat generating element 57 is integrally laminated therein. In addition, the heating element 57 may be formed on both sides of the back electrode 64 to be described later, and may be formed only on one side of the back electrode 64 or to surround the back electrode 64.

A surface electrode 56 is formed on the surface 55a of the insulating substrate 55. The surface electrode 56 is connected to a fusible conductor 53 that connects the first and second external electrodes 51 and 52 through a connection material such as solder. In addition, the surface electrode 56 is continuous with the through hole 58 formed in the thickness direction of the insulating substrate 55. In the surface electrode 56, when the soluble conductor 53 is melted by the heat generation of the heat generating element 57, the molten conductor 53a is agglomerated and can be sucked into the through hole 58 by a capillary phenomenon. Thereby, the protection element 50 does not excessively aggregate on the surface 55a of the insulating substrate 55 even when the cross-sectional area of the fusible conductor 53 is increased in order to cope with the high current application. Without, it is possible to reliably cut off the current path between the first and second external electrodes 51 and 52.

As shown in FIG. 11A, the through hole 58 is formed in the center in the width direction of the surface electrode 56. In addition, a plurality of through holes 58 may be formed. Here, a plurality of through-holes 58 are formed in a line in a straight line.

On the inner circumferential surface of the through hole 58, a conductive layer 65 connected to the surface electrode 56 is formed. The conductive layer 65 is, for example, a metallic material in which the molten conductor 53a is wet and spread, and is formed by a paste treatment, a plating treatment, or the like. Thereby, the protection element 50 becomes easy to draw in the molten conductor 53a aggregated in the surface electrode 56 into the through hole 58, and can attract more molten conductor 53a.

In addition, the protective element 50 has a through hole 58 and a back electrode 64 connected to the conductive layer 65 in the back surface 55b of the insulating substrate 55. The protection element 50 forms the back electrode 64, so that the molten conductor 53a sucked into the through-hole 58 along the conductive layer 65 is agglomerated on the back electrode 64, and thus more melting The conductor 53a can be sucked.

In addition, as described above, in the vicinity of the back electrode 64, for example, on both sides, one side, or around, the above-described heat generating elements 57 are formed. Thereby, the protection element 50, the heat of the heating element 57 is efficiently transmitted to the back electrode 64, the conductive layer 65, and the surface electrode 56, and quickly heats the soluble conductor 53, You can fuse.

In addition, in the protection element 50, a part or all of the through hole 58 is filled with a material the same as or similar to the soluble conductor 53, or a preliminary solder 66 having a lower melting point than the soluble conductor 53. In the preliminary solder 66, when the heating element 57 generates heat, the temperature on the rear surface 55b side of the insulating substrate 55 is higher than the temperature on the surface 55a side, and the conductive layer 65 or the surface electrode ( 56) or the rear electrode 64 or the heating element lead electrode 63 is melted before the soluble conductor 53, since the temperature is higher than the insulating substrate 55, and then the molten conductor 53a is passed through the through hole 58 I can draw in. Thereby, the molten conductor 53a moves from the front surface 55a of the insulating substrate 55 to the rear surface 55b, regardless of the posture, between the first external electrode 51 and the second external electrode 52 The current path can be reliably cut off.

The heat generating element lead electrode 63 formed on the rear surface 55b of the insulating substrate 55 overlaps the rear electrode 64 of the rear surface 55b and is electrically connected. In addition, the heating element lead electrode 63 is connected to the soluble conductor 53 via the back electrode 64, the through hole 58 and the preliminary solder 66, and the surface electrode 56, and a tab formed at one end ( 63a) is connected to the first heating element electrode 59.

Further, on the outside of the surface electrode 56 of the surface 55a of the insulating substrate 55, island-like electrodes 67a and 67b are formed to be separated from each other. When the soluble conductor 53 is melted, the island-like electrodes 67a and 67b partially replace the molten conductor 53a with the surface electrode 56 or the first and second external electrodes 51 and 52 due to wettability. Keep it apart.

In the protective element 50 as described above, when the heat generating element 57 generates heat by forming the heat generating element 57 on the rear surface 55b side of the insulating substrate 55, the rear surface 55b side becomes the front surface 55a side. The temperature becomes higher. In addition, the conductive layer 65, the surface electrode 56, the back electrode 64, and the heat generating element lead electrode 63 are generally conductive materials such as a copper pattern, and are excellent in thermal conductivity. Further, the rear electrode 64 of the rear surface 55b is formed between the heat generating elements 57, and the heat of the heat generating elements 57 is efficiently transmitted. Therefore, the protection element 50 can attract more molten conductors 53a to the rear surface 55b side of the insulating substrate 55, and increase the cross-sectional area of the soluble conductor 53 in order to cope with a large current, Even when the melting amount of the molten conductor 53a at the time of melting increases, the soluble conductor 53 can be stably melted.

In addition, in the protective element 50, by filling the preliminary solder 66 in the through hole 58, the conductive layer 65, the surface electrode 56, the back electrode 64, and the heating element lead electrode 63 are insulated. By increasing the temperature before the substrate 55, the preliminary solder 66 is melted before the soluble conductor 53, and the molten conductor 53a can be drawn into the through hole 58. Thereby, the molten conductor 53a is efficiently sucked from the front surface 55a of the insulating substrate 55 to the rear surface 55b, and between the first external electrode 51 and the second external electrode 52, regardless of the posture. The current path of can be reliably cut off. In addition, the suction member 54 may fill a part or all of the through holes 58 together with the preliminary solder 66 or instead of the preliminary solder 66. Also by filling the flux, the wettability of the soluble conductor 53 can be improved, and the molten conductor 53a can be efficiently drawn into the through hole 58.

[How to use the protection element]

As shown in FIG. 12, the protection element 50 is used for the circuit in the battery pack 30 of the lithium ion secondary battery mentioned above. The protection element 50 is connected on the charge/discharge current path between the battery stack 35 and the charge/discharge control circuit 40, similarly to the protection element 10, and its operation is applied to the current control element 37. Controlled by

In the battery pack 30, the protection element 50 has a circuit configuration as shown in FIG. 13. That is, the protection element 50 is connected between the first and second external electrodes 51 and 52, and a soluble conductor connected to the surface electrode 56 formed on the surface 55a of the insulating substrate 55 ( It is a circuit configuration composed of a heat generating element 57 that melts the soluble conductor 53 by energization and heat generation through the surface electrode 56. The heating element 57 has one end connected to the surface electrode 56 via the first heating element electrode 59, the heating element lead electrode 63, the back electrode 64, and the conductive layer 65, and the other is the second It is connected to the 3rd external connection electrode 61 via the heating element electrode 60. In the protection element 50, the soluble conductor 53 is connected in series on the charge/discharge current path between the first and second external electrodes 51, 52, and the heat generating element 57 is connected through the surface electrode 56. While being connected to the soluble conductor 53, it is connected to the current control element 37 via the 3rd external connection electrode 61.

In the battery pack 30 having such a circuit configuration, when the voltage value of the battery cells 31 to 34 becomes a voltage exceeding a predetermined over-discharge or over-charge state, the current control element 37 becomes the protection element 50. ) Is operated, and the charge/discharge current path of the battery stack 35 is controlled to be cut off regardless of the switch operation of the current control elements 41 and 42. Specifically, in the protection element 50, the heat generating element 57 generates heat, and heats the soluble conductor 53 and the preliminary solder 66 in the through hole 58 as shown in FIG. 14A. At this time, in the insulating substrate 55, the side of the rear surface 55b on which the heat generating element 57 is disposed becomes a temperature gradient having a higher temperature than the side of the front surface 55a. The rear electrode 64 on the rear surface 55b side of the insulating substrate 55, the heating element lead electrode 63, the conductive layer 65 of the through hole 58, or the surface electrode of the surface 55a of the insulating substrate 55 (56) Silver is more excellent in thermal conductivity than an insulating substrate 55 such as ceramic.

Therefore, the heat of the heating element 57 is mainly composed of the rear electrode 64 formed between the heating elements 57, the heating element lead electrode 63 on the heating element 57, the conductive layer 65 of the through hole 58, and the surface. It is transmitted to the surface 55a of the insulating substrate 55 through the path of the surface electrode 56 of 55a, and the preliminary solder 66 and the soluble conductor 53 in the path are melted. Of course, the soluble conductor 53 is inferior in efficiency, but it is also melted by heat transmitted through an insulating layer such as ceramic of the insulating substrate 55. Thereby, as shown in FIG. 14(B), the preliminary solder 66 starts melting earlier than the soluble conductor 53, and gradually the front electrode 56, the conductive layer 65, the back electrode 64, the heating element By the wettability of the lead electrode 63, the soluble conductor 53, which has moved to the back surface 55b of the insulating substrate 55, and has fallen behind the preliminary solder 66 and melted, also fills the through hole 58 by the wettability. Through it, it moves as if being pulled to the back surface 55b side of the insulating board|substrate 55. In addition, a part of the molten conductor 53a is also held in the island-like electrodes 67a and 67b of the surface 55a of the insulating substrate 55 (refer to the arrow in Fig. 14A). Thereby, the protection element 50 can reliably melt the soluble conductor 53 on the current path between the first and second external electrodes 51 and 52.

The protection element 50 of the present invention, as described above, guides a large amount of soluble conductor 53 (solder) from the front surface 55a of the insulating substrate 55 to the rear surface 55b, so that the soluble conductor 53 ) Can be easily melted. Here, in order to confirm whether the fusible conductor 53 can be fused stably irrespective of the posture in which the protection element 50 is arranged, experiments shown in Figs. 15 and 16 were performed. Here, FIG. 16 shows the relationship between each posture of the protection element 50 of the present invention and the melting time shown in FIGS. 15A to 15E. In addition, here, the protection element 50 is operated at 15 W.

15(A) shows the protection element 50 mounted with the front surface 55a side of the insulating substrate 55 facing upward and the rear surface 55b side of the insulating substrate 55 facing downward. It is a plan view showing the state after melting.

15(B) shows that the protection element 50 is inverted by 90° from the posture of FIG. 15(A) so that the through hole 58 faces in the horizontal direction, and the second external electrode 52 It is a side view showing the state after melting|fusing of the protection element 50 which supported the soluble conductor 53 in the vertical direction by making it upward.

Fig. 15(C) is a protection element which rotates 90° from the posture of Fig. 15(B) again and parallels the through hole 58 in the vertical direction and supports the soluble conductor 53 in the horizontal direction ( 50) It is a side view which shows the state after melting|fusing.

Fig. 15(D) is a state in which the posture of Fig. 15(A) is turned backward. That is, it is a plan view showing the state after melting of the protection element 50 mounted with the front surface 55a side of the insulating substrate 55 facing downward and the rear surface 55b side of the insulating substrate 55 facing upward.

15(E) shows that the insulating substrate 55 is rotated 45° in the in-plane direction from the posture in which the first external electrode 51 is inverted upward, the through hole 58 is obliquely parallel, and the soluble conductor ( It is a side view showing the state after melting|fusing of the protection element 50 which supported 53) obliquely.

As shown in FIG. 16, it can be confirmed that the protective element 50 of the present invention, in any posture, does not have any variation in the melting time, and can reliably melt the soluble conductor 53. As shown in FIG.

Fig. 17 shows a protection element 100 serving as a reference example of the present invention, which is of a cohesive system. This protection element 100 is, as shown in Figs. 17(A) and (B), the insulating substrate 101 and the first and second external electrodes formed on the ends of the surface 101a of the insulating substrate 101 (102, 103), the heating element 104 formed on the surface 101a of the insulating substrate 101, and the first and second external electrodes 102, 103 are stacked over, crossing the heating element 104, A fusible conductor 105 is provided for melting the current path between the first external electrode 102 and the second external electrode 103 by heating by the heating element 104. The heating element 104 is formed at both ends on the surface 101a of the insulating substrate 101, the first and second heating element electrodes 106 and 107 connecting a power source in order to heat the heat generating element 104 by passing a current. It is connected.

The first and second heating element electrodes 106 and 107 are formed on the surface 101a of the insulating substrate 101. The first heat generating electrode 106 is connected to the heat generating element 104 and the tab 108a of the heat generating element lead electrode 108 is connected. The second heat generating electrode 107 is connected to the heat generating element 104 and is connected to an external connection electrode (not shown).

The heat generating element lead electrode 108 has one end connected to the soluble conductor 105 and the other end connected to the first heat generating element electrode 106 by a tab 108a of the heat generating element lead electrode 108. Further, on the outside of the heat generating element 104, the island-like electrodes 109a and 109b are formed to be separated from the heat generating element 104. When the soluble conductor 105 is melted, the island-like electrodes 109a and 109b hold the molten conductor 105a in which the soluble conductor 105 is melted by wettability, and the first external electrode 102 and the second The current path between the external electrodes 103 is fused. That is, in the protection element 100, no through holes are formed in the insulating substrate 101, and the molten conductor 105a does not move to the rear surface 101b of the insulating substrate 101.

This protection element 100 also uses the same usage as the protection element 50, and as shown in FIG. 12, the voltage value of the battery cells 31 to 34 is determined by the detection signal output from the detection circuit 36. When a voltage exceeding a predetermined over-discharge or over-charge state is reached, the current control element 37 operates the protection element 100 to pass the charge/discharge current path of the battery stack 35 to the current control elements 41 and 42. ), it is blocked regardless of the operation of the switch. Thereby, the heating element 104 generates heat, and as shown in Fig. 17(C), the soluble conductor 105 is melted, and a part of the molten conductor 105a is held by the island electrodes 109a, 109b, and the current path Block.

19 shows the relationship between the posture of the protective element 100 serving as a reference example and the melting time. In addition, here, the protection element 100 is operated at 15 W. In addition, each posture of Figs. 18(A)-(E) corresponds to each posture of Figs. 15(A)-(E).

18(A) is a state after melting of the protection element 100 mounted with the front surface 101a side of the insulating substrate 101 upward and the rear surface 101b side of the insulating substrate 101 downward It is a plan view showing.

Fig. 18(B) shows the protection element 100 is inverted 90° from the posture of Fig. 18(A), the first external electrode 102 is turned upward, and the soluble conductor 105 is supported in the vertical direction. It is a side view showing the state after melting|fusing of the element 100.

Fig. 18(C) is a side view showing a state after melting of the protection element 100 which rotates 90 degrees from the posture of Fig. 18(B) and supports the soluble conductor 105 in the horizontal direction.

Fig. 18(D) is a state in which the posture of Fig. 18(A) is turned backward. That is, it is a plan view showing the state after melting of the protective element 100 mounted with the front surface 101a side of the insulating substrate 101 facing downward and the rear surface 101b side of the insulating substrate 101 facing upward.

18(E) is a protective element 100 in which the insulating substrate 101 is rotated 45° in the in-plane direction from the posture in which the first external electrode 102 is inverted upward, and the soluble conductor 105 is obliquely supported. It is a side view showing the state after melting.

19 shows the melting time of the soluble conductor 105 when the protective element 100 of the reference example is in the same posture as in FIGS. 18A to 18E.

As shown in FIG. 19, it can be confirmed that the protection element 100 of the reference example has a large variation in the melting time depending on the wiring of the protection element 100. That is, the protection element 50 of the present invention can reduce the deviation of the melting time regardless of the posture compared to the protection element 100 of the reference example, and thus, it can be reliably used at an approximately constant time regardless of the posture. The conductor 53 can be melted.

In addition, as shown in FIG. 20, as shown in FIG. 11(B), the through holes 58 may be formed in two rows as shown in FIG. 20(A), except when forming in a line in a straight line. , You may form more than that. Moreover, as shown in FIG. 20(B), it may not consist of a plurality of through-holes, but may be configured with an elongated slit 58a or a plurality of them.

[Heating element]

In addition, the protective element to which the present invention is applied may use the suction member 70 in which the heat generating element 57 is formed on the surface 55a side of the insulating substrate 55 as shown in FIG. 21. In addition, in the following description, the same reference|symbol is attached|subjected to the member similar to the above-mentioned protection element 50, and the detail is abbreviate|omitted. The protection element 71 using the suction member 70 in which the heat generating element 57 is formed on the surface 55a side of the insulating substrate 55, the heat generating element 57 is formed on the surface 55a of the insulating substrate 55 Together, it is covered by the insulating member 62.

The heat generating element 57 is connected to the first and second heat generating element electrodes 59 and 60 formed at both ends of the surface 55a of the insulating substrate 55 in the same manner. The first heat generating electrode 59 is connected to the soluble conductor 53 via the heat generating body lead electrode 63, whereby the heat generating body 57 is connected to the soluble conductor 53. Further, the second heating element electrode 60 is connected to the third external connection electrode 61 (see Figs. 12 and 13), and thereby is connected to a power source for causing the heating element 57 to generate heat.

The heat generating element 57 is covered by the insulating member 62, and the heat generating element lead electrode 63 is disposed so as to face the heat generating element 57 through the insulating member 62. The insulating member 62 may be a laminated substrate in which the heat generating element 57 is integrally laminated therein. In addition, the heating element 57 may be formed on both sides of the surface electrode 56, and may be formed only on one side of the surface electrode 56 or surrounding the surface electrode 56.

In addition, the heat generating element lead electrode 63 is formed on the surface 55a of the insulating substrate 55 by overlapping the heat generating element 57 via the insulating member 62. The heat generating element lead electrode 63 is connected to the soluble conductor 53 via the surface electrode 56, and the tab 63a formed at one end is connected to the first heat generating element electrode 59.

In addition, in the protective element 71, the through hole 58 is formed in the same manner as the protective element 50 described above, and the conductive layer 65 or the back electrode 64 is formed, and the through hole 58 A part or all of the inside may be filled with a preliminary solder 66. In addition, the suction member 70 may fill a part or all of the through holes 58 together with the preliminary solder 66 or instead of the preliminary solder 66. Also by filling the flux, the wettability of the soluble conductor 53 can be improved, and the molten conductor 53a can be efficiently drawn into the through hole 58.

The protection element 71 can efficiently transfer heat to the soluble conductor 53 when the heating element 57 generates heat by forming the heating element 57 on the surface 55a side of the insulating substrate 55, The soluble conductor 53 can be melted quickly. In addition, in the initial stage of heat generation, the protection element 71 has a temperature gradient in which the front surface 55a side of the insulating substrate 55 has a higher temperature than the rear surface 55b side. Accordingly, the protection element 71 is formed in the through hole 58 through the conductive layer 65 continuous with the surface electrode 56 while the molten conductor 53a is aggregated on the high-temperature surface electrode 56. The soluble conductor 53 can be reliably melted even when a large amount of molten conductor 53a is melted due to a large cross-sectional area.

[Example]

As described above, the protection element 71 of the present invention guides a large amount of soluble conductor 53 from the front surface 55a of the insulating substrate 55 to the rear surface 55b to facilitate the soluble conductor 53 It can be courageous. Here, in order to confirm whether the fusible conductor 53 can be fused stably irrespective of the posture in which the protection element 71 is arranged, experiments shown in Figs. 22 and 23 were performed. In the protective element 71 used in the experiment, as an insulating substrate 55, a 0.85 phi through hole 58 was formed on an alumina-based substrate having a thickness of 0.635 mm, and a Ni/Au plating treatment was performed on the inner surface thereof. In addition, as the soluble conductor 53, a Sn-Ag-Cu-based metal foil having a thickness of 0.35 mm was subjected to an Ag plating treatment having a thickness of 6 µm.

When such a protection element 71 was operated at 31 W, the melting time of the soluble conductor 53 in each posture shown in FIG. 22 was measured. Here, FIG. 23 shows the relationship between each posture of the protection element 71 of the present invention and the melting time shown in FIGS. 22A to 22E. In addition, each posture of Figs. 22(A)-(E) corresponds to each posture of Figs. 15(A)-(E).

22(A) shows the state after melting of the protection element 71 mounted with the front surface 55a side of the insulating substrate 55 facing upward and the rear surface 55b side of the insulating substrate 55 facing downward. It is a plan view showing.

Fig. 22(B) shows that the protection element 71 is inverted 90° from the posture of Fig. 22(A) so that the through hole 58 faces in the horizontal direction, and the second external electrode 52 is moved upward. It is a side view showing the state after melting of the protection element 71 which supported the soluble conductor 53 in the vertical direction.

22(C) is a protection element which rotates 90° from the posture of FIG. 22(B) again, parallelizes the through hole 58 in the vertical direction, and supports the soluble conductor 53 in the horizontal direction ( It is a side view showing the state after melting of 71).

-Fig. 22(D) is a state with the posture of Fig. 22(A) facing backwards. That is, it is a plan view showing the state after melting of the protection element 71 mounted with the front surface 55a side of the insulating substrate 55 facing downward and the rear surface 55b side of the insulating substrate 55 facing upward.

22(E) shows that the insulating substrate 55 is rotated 45° in the in-plane direction from the position in which the second external electrode 52 is inverted upward, and the through-holes 58 are obliquely parallel, and the soluble conductor ( It is a side view showing the state after melting|fusing of the protection element 71 which supported 53) obliquely.

As shown in FIG. 23, it can be confirmed that the protective element 71 of the present invention, in any posture, does not have any variation in the melting time, and can reliably melt the soluble conductor 53. As shown in FIG.

In addition, the protective element to which the present invention is applied may be formed inside the insulating substrate 55 in addition to forming the heat generating element 57 on the front surface 55a or the rear surface 55b of the insulating substrate 55. In this case, the heat generating element 57 need not be covered with the insulating member 62, and the heat generating element 57 is connected to the front electrode 56 or the back electrode 64 via the conductive layer 65.

[Agglomeration Absence]

In addition, in addition to the suction members 54 and 70, the protective element to which the present invention is applied may agglomerate the molten conductor 53a and use the agglomeration member 75 that assists the melting of the soluble conductor 53 together. 24(A)(B) is a cross-sectional view of the protection element 74 in which the suction member 70 and the agglomeration member 75 are used in combination. As shown in Fig. 24(A)(B), the agglomeration member 75 includes a second insulating substrate 76, a heat generating element 77 formed on the surface 76a of the second insulating substrate 76, An insulating member 78 that covers the heat generating element 77 and a collecting electrode 79 that is laminated on the insulating member 78 and aggregates the molten conductor 53a are provided.

The agglomeration member 75 is a second insulating substrate 76, a heat generating element 77, and an insulating member 78, the insulating substrate 55 of the protection element 50, the heat generating element 57, and the insulating member 62 and The same member can be used. Further, the collecting electrode 79 can be formed by printing or firing a high melting point metal paste such as Ag or Cu, for example.

25 shows a circuit diagram of the protection element 74. The agglomeration member 75 is electrically connected to the third external connection electrode 61 via a heating element electrode (not shown) in the same way as the heating element 57, and a current control element formed in an external circuit ( By means of 37) or the like, energization is controlled in connection with the heat generating element 57 of the suction member 70. In addition, the agglomeration member 75 is connected to the collecting electrode 79 via a heating element electrode (not shown), and electrically connected to the soluble conductor 53 via the collecting electrode 79. .

The cohesive member 75 is connected to the surface of the soluble conductor 53 on the opposite side to the surface on which the suction member 70 is formed. Therefore, when the heating element 57 of the suction member 70 is energized and heat generated, the protection element 74 also conducts and generates heat at the same time as the heating element 77 of the agglomeration member 75 so that the soluble conductor 53 is energized from both sides. By heating, it melts quickly.

At this time, the protection element 74 sucks the molten conductor 53a into the through hole 58 by the suction member 70, and the molten conductor 53a by the agglomeration member 75 is connected to the collecting electrode ( By agglomeration in 79), the allowable amount to suck and hold the molten conductor 53a is increased. Therefore, the protection element 74 can be reliably melted even when a large amount of molten conductors 53a is generated by using the soluble conductors 53 having a large cross-sectional area and a fixed level. Maintain and improve characteristics.

In addition, the protective element 74 can quickly melt the soluble conductor 53 even when a coating structure in which the low melting point metal constituting the inner layer is coated with a high melting point metal is used as the soluble conductor 53. That is, the soluble conductor 53 covered with a high melting point metal takes time to heat to a temperature at which the high melting point metal of the outer layer melts even when the heating elements 57 and 77 generate heat. Here, the protection element 74 includes the suction member 70 and the agglomeration member 75, and simultaneously heats the heating elements 57 and 77, so that the high melting point metal of the outer layer can be quickly heated to the melting temperature. . Therefore, according to the protection element 74, the thickness of the high-melting-point metal layer constituting the outer layer can be increased, and the fast-melting characteristic can be maintained while further enhancing the high-melting point.

In addition, it is preferable that the protection element 74 faces the collecting electrode 79 of the cohesive member 75 with the through hole 58 of the suction member 70. Thereby, more molten conductors 53a are gathered on the through-holes 58, and the molten conductors 53a can be efficiently sucked into the through-holes 58, and the soluble conductors 53 can be quickly melted. .

[Multiple suction members]

In addition, the protective element to which the present invention is applied may be provided with a plurality of suction members 54 and 70 and disposed on the front and rear surfaces of the soluble conductor 53 as shown in FIG. 26(A) (B). In the protection element 80 shown in FIG. 26, for example, the above-described suction member 54 is disposed on the front and rear surfaces of the soluble conductor 53, respectively. 27 is a circuit diagram of the protection element 80. Each of the suction members 54 disposed on the front and rear surfaces of the soluble conductor 53 has one end of the heating element 57 interposed between the first heating element electrode 59 and the heating element lead electrode 63, and the soluble conductor 53 Is connected to, and the other end of the heating element 57 is connected to a power source for heating the heating element 57 via the second heating element electrode 60 and the third external connection electrode 61.

When the protective element 80 melts the soluble conductor 53, the heating elements 57 of the suction members 54 and 54 generate heat, respectively, and the molten conductor 53a is sucked into each through hole 58. Let it. Therefore, the protection element 80 increases the cross-sectional area of the fusible conductor 53 in order to cope with the use of a high current, so that even when a large amount of the molten conductor 53a is generated, it is sucked by the plurality of suction members 54 to ensure that The soluble conductor 53 can be melted. Moreover, the protection element 80 can melt|dissolve the soluble conductor 53 more quickly by attracting the molten conductor 53a by the several suction members 54.

The protective element 80 can quickly melt the soluble conductor 53 even when a coating structure in which the low melting point metal constituting the inner layer is coated with a high melting point metal is used as the soluble conductor 53. That is, the soluble conductor 53 covered with a high melting point metal takes time to heat to a temperature at which the high melting point metal of the outer layer melts even when the heating element 57 generates heat. Here, the protective element 80 is provided with a plurality of suction members 54 and simultaneously heats each heat generating element 57, so that the high melting point metal of the outer layer can be quickly heated to the melting temperature. Therefore, according to the protection element 80, the thickness of the high-melting-point metal layer constituting the outer layer can be increased, and the fast-melting characteristic can be maintained while further improving the high-melting point.

In addition, as for the protection element 80, as shown in FIG. 26, it is preferable that a pair of suction members 54, 54 oppose and are connected to the soluble conductor 53. Thereby, the protective element 80 can heat the same point of the soluble conductor 53 from both sides simultaneously with the pair of suction members 54, 54 and suck the molten conductor 53a, and more The soluble conductor 53 can be quickly heated and melted.

In addition, the protective element 80 uses the suction member 54 in which the heat generating element 57 is formed on the rear surface 55b side of the insulating substrate 55 as a suction member, and the heat generating element 57 is an insulating substrate ( A plurality of suction members 70 formed on the surface 55a side of 55) may be used, or both suction members 54 and 70 may be used in combination.

[Composition of usable conductor]

As described above, the soluble conductors 13 and 53 may contain a low melting point metal and a high melting point metal. As the low melting point metal, it is preferable to use a solder such as Pb-free solder containing Sn as a main component, and as the high melting point metal, it is preferable to use Ag, Cu, or an alloy containing these as a main component. At this time, as the soluble conductors 13 and 53, a soluble conductor in which a high melting point metal layer 90 is formed as an inner layer and a low melting point metal layer 91 is formed as an outer layer may be used as shown in Fig. 28(A). . In this case, the soluble conductors 13 and 53 may have a structure in which the entire surface of the high melting point metal layer 90 is covered by the low melting point metal layer 91, except for a pair of side surfaces facing each other. You can open it. The coating structure of the high melting point metal layer 90 or the low melting point metal layer 91 can be formed using a known film forming technique such as plating.

In addition, as shown in FIG. 28(B), as the soluble conductors 13 and 53, a soluble conductor in which a low melting point metal layer 91 is formed as an inner layer and a high melting point metal layer 90 is formed as an outer layer may be used. Also in this case, the soluble conductors 13 and 53 may have a structure in which the entire surface of the low melting point metal layer 91 is covered by the high melting point metal layer 90, except for a pair of side surfaces facing each other. It may be a structure.

In addition, the soluble conductors 13 and 53 may have a laminated structure in which the high melting point metal layer 90 and the low melting point metal layer 91 are laminated, as shown in FIG. 29.

In this case, the soluble conductor 13 is the first and second electrodes 11 and 12, the surface electrode 22, or the first and second external electrodes 51 and 52, as shown in Fig. 29(A). ) Or a lower layer connected to the surface electrode 56, and a low melting point metal layer 91 formed as an upper layer on the upper surface of the high melting point metal layer 90, which is formed as a two-layer structure consisting of an upper layer stacked on the lower layer. It may be laminated, or conversely, a high melting point metal layer 90 serving as an upper layer may be laminated on the upper surface of the low melting point metal layer 91 serving as a lower layer. Alternatively, the soluble conductors 13 and 53 may be formed as a three-layer structure consisting of an inner layer and an outer layer laminated on the upper and lower surfaces of the inner layer, as shown in FIG. 29(B), or the high melting point metal layer 90 serving as the inner layer. The low melting point metal layer 91 serving as the outer layer may be laminated on the upper and lower surfaces, or conversely, the high melting point metal layer 90 serving as the outer layer may be laminated on the upper and lower surfaces of the low melting point metal layer 91 serving as the inner layer.

Further, the soluble conductors 13 and 53 may have a multilayer structure of four or more layers in which the high melting point metal layers 90 and the low melting point metal layers 91 are alternately laminated, as shown in FIG. 30. In this case, the soluble conductors 13 and 53 may have a structure covered with the metal layer constituting the outermost layer, excluding the entire surface or a pair of side surfaces facing each other.

Further, the soluble conductors 13 and 53 may partially laminate the high melting point metal layer 90 in a stripe shape on the surface of the low melting point metal layer 91 constituting the inner layer. 31 is a plan view of the soluble conductors 13 and 53.

The soluble conductors 13 and 53 shown in Fig. 31(A) are formed in a plurality of linear high melting point metal layers 90 in the length direction at predetermined intervals in the width direction on the surface of the low melting point metal layer 91, so that the length A linear opening 92 is formed along the direction, and the low melting point metal layer 91 is exposed from the opening 92. In the soluble conductors 13 and 53, when the low-melting-point metal layer 91 is exposed from the opening 92, the contact area between the molten low-melting-point metal and the high-melting-point metal increases, thereby preventing the erosion action of the high-melting-point metal layer 90. It can be promoted more, and the melting property can be improved. The opening 92 can be formed, for example, by partially plating the metal constituting the high melting point metal layer 90 on the low melting point metal layer 91.

In addition, the soluble conductors 13 and 53 have a linear high melting point metal layer 90 on the surface of the low melting point metal layer 91 at predetermined intervals in the length direction, as shown in Fig. 31(B), in the width direction. By forming a plurality, the linear openings 92 may be formed along the width direction.

In addition, the soluble conductors 13 and 53 are formed over the entire surface of the high melting point metal layer 90 while forming the high melting point metal layer 90 on the surface of the low melting point metal layer 91 as shown in FIG. 32. A circular opening 93 may be formed, and the low melting point metal layer 91 may be exposed from the opening 93. The opening 93 can be formed, for example, by partially plating the metal constituting the high melting point metal layer 90 on the low melting point metal layer 91.

In the soluble conductors 13 and 53, when the low melting point metal layer 91 is exposed from the opening 93, the contact area between the molten low melting point metal and the high melting point metal increases, thereby further promoting the erosion action of the high melting point metal. The melting property can be improved.

In addition, as shown in FIG. 33, the soluble conductors 13 and 53 form a large number of openings 94 in the high melting point metal layer 90 serving as the inner layer, and in the high melting point metal layer 90, plating techniques, etc. The low melting point metal layer 91 may be formed by using, and may be filled in the opening 94. Thereby, in the soluble conductors 13 and 53, the area in which the low-melting-point metal to be melted contacts the high-melting-point metal is increased, so that the low-melting-point metal can melt the high-melting-point metal in a shorter time.

Moreover, as for the soluble conductors 13 and 53, it is preferable to form the volume of the low-melting-point metal layer 91 larger than the volume of the high-melting-point metal layer 90. The soluble conductors 13 and 53 are heated by the heat generation of the heat generating elements 25 and 57, and the low melting point metal melts to melt the high melting point metal, thereby allowing rapid melting and melting. Therefore, the soluble conductors 13 and 53 promote this melting action by forming the volume of the low melting point metal layer 91 to be larger than the volume of the high melting point metal layer 90, and quickly, the first and second electrodes 11 , 12), or between the first and second external electrodes 51 and 52 may be blocked.

In addition, as shown in FIG. 34, the soluble conductors 13 and 53 are formed in a substantially rectangular plate shape, covered with a high melting point metal constituting the outer layer, and formed to be thicker than the main surface portion 96. Even if the first side edge portion 97 and the low melting point metal constituting the inner layer are exposed to have a pair of second side edge portions 98 facing each other formed to have a thickness thinner than that of the first side edge portion 97 do.

The first side edge portion 97 is formed thicker than the main surface portion 96 of the soluble conductors 13 and 53 while the side surface is covered with the high melting point metal layer 90. On the side surface of the second side edge portion 98, a low melting point metal layer 91 surrounding the outer periphery by a high melting point metal layer 90 is exposed. The second side edge portion 98 is formed to have the same thickness as the main surface portion 96 except for both ends adjacent to the first side edge portion 97.

In the protection element 1, in the soluble conductor 13, the first side edge portion 97 is mounted along the width direction of the first and second electrodes 11, 12, and the second side edge portion 98 ) Is connected between the first and second electrodes 11 and 12 in the direction in which both ends of the current supply direction become. Similarly, in the protection element 50, in the soluble conductor 53, the first side edge portion 97 is mounted along the width direction of the first and second external electrodes 51, 52, and the second side The edge portion 98 is connected between the first and second external electrodes 51 and 52 in a direction in which both ends of the energization direction become.

Thereby, in the protection elements 1 and 50, the soluble conductors 13 and 53 are quickly melted, and the current path of the external circuit can be cut off.

That is, the second side edge portion 98 is formed to be relatively thinner than the first side edge portion 97. Moreover, on the side surface of the 2nd side edge part 98, the low melting point metal layer 91 which comprises an inner layer is exposed. Thereby, the melting action of the high melting point metal layer 90 by the low melting point metal layer 91 acts on the second side edge portion 98, and the thickness of the melting point metal layer 90 is also the first side edge portion. By being formed thinner than 97, compared with the 1st side edge part 97 formed thick by the high melting point metal layer 90, it can melt|dissolve quickly with less heat energy. In contrast, the first side edge portion 97 is thickly covered by the high melting point metal layer 90 and requires a large amount of heat energy until it is melted compared to the second side edge portion 98.

Therefore, the protection elements 1, 50 are immediately between the first electrode 11 and the second electrode 12, or the second electrode 12, on which the second side edge portion 98 is covered, or the second side edge portion 98 immediately when the heating elements 25 and 57 generate heat. Between the first external electrode 51 and the second external electrode 52 is melted. Thereby, the protection elements 1 and 50 block the charge/discharge path between the first and second electrodes 11 and 12 or between the first and second external electrodes 51 and 52, and the heating element 25 The power supply path to the, 57) is blocked, and the heat generation of the heat generating elements 25 and 57 is stopped.

The soluble conductors 13 and 53 having such a configuration are manufactured by coating a low melting point metal foil such as a solder foil constituting the low melting point metal layer 91 with a metal such as Ag constituting the high melting point metal layer 90 . As a method of coating a low melting point metal layer foil with a high melting point metal, an electrolytic plating method capable of continuously performing high melting point metal plating on a long low melting point metal foil becomes advantageous in terms of work efficiency and manufacturing cost.

When high melting point metal plating is performed by electrolytic plating, the electric field strength becomes relatively strong at the edge portion of the long low melting point metal foil, that is, at the side edge portion, and the high melting point metal layer 90 is plated thickly (see Fig. 34). . Thereby, the long conductor ribbon 95 is formed in which the side edge part is formed thick by the high melting point metal layer. Next, soluble conductors 13 and 53 are manufactured by cutting this conductor ribbon 95 into a predetermined length in the width direction (C-C' direction in Fig. 34) orthogonal to the longitudinal direction. Thereby, in the soluble conductors 13 and 53, the side edge portion of the conductor ribbon 95 becomes the first side edge portion 97, and the cut surface of the conductor ribbon 95 becomes the second side edge portion 98. In addition, the first side edge portion 97 is covered with a high melting point metal, and the second side edge portion 98 is a pair of high melting point metal layers 90 on the end face (cut surface of the conductor ribbon 95). ) And the low melting point metal layer 91 surrounded by the high melting point metal layer 90 is exposed to the outside.

1 protection element,
10 first insulating substrate,
10a surface,
If 10b,
11 first electrode,
11a first external connection electrode,
11b conductive layer,
12 second electrode,
12a second external connection electrode,
12b conductive layer,
13 soluble conductor,
13a molten conductor,
14 flux,
15 cover member,
20 suction hole,
21 conductive layer,
22 surface electrode,
23 back electrode,
24 protection elements,
25 heating elements,
26 insulating layer,
27 third external connection electrode,
30 battery pack,
30a positive terminal,
30b negative terminal,
31 to 34 battery cells,
35 battery stack,
36 detection circuit,
37 current control element,
40 charge/discharge control circuit,
41, 42 current control elements,
43 control unit,
50 protection elements,
51 first external electrode,
52 second external electrode,
53 soluble conductor,
53a molten conductor,
54 suction member,
55 insulation member,
55a surface,
55b,
56 surface electrode,
57 heating element,
58 through hole,
59 first heating element electrode,
60 second heating element electrode,
61 third external connection electrode,
62 insulation member,
63 heating element lead-out electrode,
63a tab,
64 back electrode,
65 conductive layer,
66 spare solder,
67 islet electrode,
70 suction member,
71 protection element,
74 protection element,
75 cohesive member,
76 second insulating substrate,
77 heating element,
78 insulation member,
79 collecting electrode,
80 protection elements,
90 high melting point metal layer,
91 low melting point metal layer,
95 conductor ribbon,
97 1st side edge,
98 second side edge

Claims (63)

A first insulating substrate,
Having a soluble conductor mounted on the surface of the first insulating substrate,
A suction hole for sucking the molten soluble conductor is opened on the surface of the first insulating substrate,
The suction hole is a through hole or a non-penetrating hole formed in a thickness direction of the first insulating substrate while a conductive layer is formed on the inner surface thereof. The method of claim 1,
A protective element, wherein a surface electrode connected to the conductive layer is formed on a surface of the first insulating substrate. The method of claim 2,
The suction hole is a through hole,
A protection element, wherein a rear electrode connected to the conductive layer is formed on a rear surface of the first insulating substrate. The method according to any one of claims 1 to 3,
One or more suction holes are formed, the protection element. The method according to any one of claims 1 to 3,
In the first insulating substrate, first and second electrodes connected to the soluble conductor are formed,
The first and second electrodes are connected to an external connection electrode formed on a rear surface of the first insulating substrate. The method of claim 5,
A protection element, wherein a heating element for melting the soluble conductor is formed on the first insulating substrate. The method of claim 6,
The heating element is formed on the surface of the first insulating substrate, and is overlapped with the fusible conductor via an insulating member. The method of claim 6,
The heating element is formed on the rear surface of the first insulating substrate and overlaps with the fusible conductor. The method of claim 6,
The heating element is a protection element formed inside the first insulating substrate. The method according to claim 2 or 3,
A heating element for melting the soluble conductor is formed on the first insulating substrate,
The protection element, wherein the heating element is connected to the soluble conductor via the surface electrode. The method of claim 10,
In the first insulating substrate, first and second electrodes connected to the soluble conductor are formed,
The first and second electrodes are connected to an external connection electrode formed on a rear surface of the first insulating substrate. The method of claim 11,
The heating element is formed on the surface of the first insulating substrate, and is overlapped with the fusible conductor via an insulating member. The method of claim 11,
The heating element is formed on the rear surface of the first insulating substrate and overlaps with the fusible conductor. The method according to any one of claims 1 to 3,
A protection element, wherein a flux is applied to the surface of the soluble conductor. The method according to any one of claims 1 to 3,
The protective element, wherein the conductive layer contains copper, silver, gold, iron, nickel, palladium, lead, tin, or any of as a main component. The method according to any one of claims 1 to 3,
The protective element, wherein the soluble conductor is solder. The method according to any one of claims 1 to 3,
The protective element, wherein the soluble conductor contains a low melting point metal and a high melting point metal. The method of claim 17,
The low melting point metal is solder,
The high melting point metal is silver, copper, or an alloy containing silver or copper as a main component. The method of claim 17,
In the soluble conductor, an inner layer is the high melting point metal, and an outer layer is a covering structure of the low melting point metal. The method of claim 17,
In the soluble conductor, the inner layer is the low melting point metal, and the outer layer is a coating structure of the high melting point metal. The method of claim 17,
The soluble conductor is a layered structure in which the low melting point metal and the high melting point metal are stacked. The method of claim 17,
The soluble conductor is a protection element having a multilayer structure of four or more layers in which the low melting point metal and the high melting point metal are alternately stacked. The method of claim 17,
The protective element in which the soluble conductor has an opening formed in the high melting point metal formed on the surface of the low melting point metal constituting the inner layer. The method of claim 17,
The soluble conductor has a high melting point metal layer having a plurality of openings, a low melting point metal layer formed on the high melting point metal layer, and the low melting point metal is filled in the opening. The method of claim 17,
The soluble conductor is covered with the high melting point metal constituting the outer layer and formed thicker than the main surface portion, and a pair of opposed first side edge portions, and the low melting point metal constituting the inner layer are exposed to the first side. Having a pair of second side edge portions facing each other formed to have a thickness thinner than the edge portion,
The protection element, wherein the first side edge portion is mounted along the first and second electrodes formed on the surface of the first insulating substrate, and the second side edge portion is connected between the first and second electrodes. The method of claim 17,
The protective element in which the soluble conductor has a volume of the low-melting-point metal larger than that of the high-melting-point metal. One or more battery cells,
A protection element connected on the charge/discharge path of the battery cell and blocking the charge/discharge path,
The protection element,
A first insulating substrate,
It is mounted on the surface of the first insulating substrate, and has a soluble conductor serving as the charge/discharge path,
A suction hole for sucking the molten soluble conductor is opened on the surface of the first insulating substrate,
The suction hole is a through hole or a non-penetrating hole formed in the thickness direction of the first insulating substrate while the conductive layer is formed on the inner surface thereof, the battery pack. First and second external electrodes,
A soluble conductor connected between the first and second external electrodes,
It is connected to the soluble conductor, has a suction member for sucking the molten soluble conductor,
The suction member,
A first insulating substrate disposed between the first and second external electrodes,
A surface electrode formed on the surface of the first insulating substrate and connected to a part of the soluble conductor,
A heating element formed on the first insulating substrate,
It is formed in the thickness direction of the first insulating substrate, and has a through hole continuous with the surface electrode,
A protection element for blocking a current path between the first external electrode and the second external electrode by melting the soluble conductor. The method of claim 28,
The through hole is a protective element, wherein a conductive layer continuous with the surface electrode is formed on an inner circumferential surface. The method of claim 29,
It has a back electrode formed on the back surface of the first insulating substrate,
The through hole is formed between the surface electrode and the back electrode in the thickness direction of the first insulating substrate, and the conductive layer is continuous with the surface electrode and the back electrode. The method of claim 30,
The heating element is formed on the surface side of the first insulating substrate, and is electrically connected to the surface electrode. The method of claim 30,
The heating element is formed on the back side of the first insulating substrate, and is electrically connected to the back electrode. The method of claim 30,
The heating element is formed inside the first insulating substrate, and is electrically connected to the front electrode or the back electrode. The method according to any one of claims 28 to 33,
A protection element, wherein some or all of the through holes are filled with preliminary solder and/or flux. The method according to any one of claims 31 to 33,
In the first insulating substrate, when the heating element generates heat, one of the surface side or the rear surface side on which the heating element is formed becomes a temperature gradient having a higher temperature than the other. The method of claim 34,
In the first insulating substrate, when the heating element generates heat, one of the surface side or the rear surface side on which the heating element is formed becomes a temperature gradient having a higher temperature than the other. The method according to any one of claims 28 to 33,
The heating element is disposed on both sides of the through hole, the protection element. The method of claim 37,
A plurality of the through holes are formed,
The heating element is disposed on both sides of the plurality of through-holes, the protection element. The method according to any one of claims 28 to 33,
A second insulating substrate,
A heating element formed on the second insulating substrate and melting the soluble conductor,
A protective element comprising a cohesive member connected to the soluble conductor and having a collecting electrode for coagulating the molten conductor in which the soluble conductor is melted. The method of claim 39,
The cohesive member is a protective element in which the collecting electrode is connected to a surface opposite to a surface of the soluble conductor to which the suction member is connected. The method of claim 40,
The cohesive member is a protection element in which the collecting electrode faces the through hole of the suction member. The method according to any one of claims 28 to 33,
A protection element in which a plurality of the suction members are connected to the soluble conductor. The method of claim 42,
The protection element, wherein two of the suction members are connected to each other to the soluble conductor. The method of claim 39,
The soluble conductor is a protective element in which an inner layer is a low melting point metal and an outer layer is a coating structure of a high melting point metal. The method of claim 42,
The soluble conductor is a protective element in which an inner layer is a low melting point metal and an outer layer is a coating structure of a high melting point metal. One or more battery cells,
A protection element connected on the charging/discharging path of the battery cell and blocking the charging/discharging path,
A current control element for controlling energization to the protection element by detecting a voltage value of the battery cell,
The protection element,
First and second external electrodes,
A soluble conductor connected between the first and second external electrodes,
It has a suction member for sucking the molten soluble conductor,
The suction member,
A first insulating substrate disposed between the first and second external electrodes,
A surface electrode formed on the surface of the first insulating substrate and connected to a part of the soluble conductor,
A heating element formed on the first insulating substrate,
It is formed in the thickness direction of the first insulating substrate, and has a through hole continuous with the surface electrode,
The battery pack, wherein the soluble conductor is melted to block a current path between the first external electrode and the second external electrode. A first insulating substrate,
First and second external electrodes,
An intermediate electrode formed between the first external electrode and the second external electrode on one side of the first insulating substrate,
A heating element formed on the other side of the first insulating substrate,
The first external electrode and the second external electrode are connected to one surface of the first insulating substrate and connected to the intermediate electrode and across the first and second external electrodes, and heated by the heating element. A fusible conductor that fuses the current path between,
A heating element lead electrode formed on the other side of the first insulating substrate and electrically connected to one terminal of the heating element;
A protective element comprising a through hole formed between the intermediate electrode and the heating element lead electrode in the thickness direction of the first insulating substrate, and formed on an inner surface of the intermediate electrode and a conductive layer continuous with the heating element lead electrode. The method of claim 47,
In addition, the protection element includes a preliminary solder filled in the through hole. The method of claim 47,
The protection element, wherein the first insulating substrate has a temperature gradient in which the other surface side of the first insulating substrate has a higher temperature than the one surface side when the heating element generates heat. The method of claim 47,
The heating element is a protection element, characterized in that formed on both sides of the through hole. The method of claim 50,
The through hole is plural,
The heating element is a protection element, characterized in that disposed on both sides of the plurality of through holes. One or more battery cells,
A protection element connected to block a current flowing through the battery cell,
A current control element for controlling a current heating the protection element by detecting a voltage value of each of the battery cells,
The protection element,
A first insulating substrate,
First and second external electrodes,
An intermediate electrode formed between the first external electrode and the second external electrode on one side of the first insulating substrate,
A heating element formed on the other side of the first insulating substrate,
The first external electrode and the second external electrode are connected to one surface of the first insulating substrate and connected to the intermediate electrode and across the first and second external electrodes, and heated by the heating element. A fusible conductor that fuses the current path between,
A heating element lead electrode formed on the other side of the first insulating substrate and electrically connected to one terminal of the heating element;
A battery pack having a through hole formed between the intermediate electrode and the heating element lead electrode in a thickness direction of the first insulating substrate, and formed on an inner surface of the intermediate electrode and a conductive layer continuous with the heating element lead electrode. First and second external electrodes,
A soluble conductor connected between the first and second external electrodes,
It is connected to the soluble conductor, has a suction member for sucking the molten soluble conductor,
The suction member,
A first insulating substrate disposed between the first and second external electrodes,
A heating element formed on a surface of the first insulating substrate facing the fusible conductor,
An insulating member covering the heating element,
A heating element lead electrode connected to the heating element and formed on the surface of the first insulating substrate and connected to a part of the soluble conductor,
It is formed in the thickness direction of the first insulating substrate, and has a through hole continuous with the heating element lead electrode,
Having a plurality of the suction members,
A protection element for blocking a current path between the first external electrode and the second external electrode by melting the soluble conductor. The method of claim 53,
A back electrode connected to the through hole is formed on a back surface of the first insulating substrate opposite to the surface,
The heating element is connected to the fusible conductor, the through hole, and the back electrode via the heating element lead electrode. The method of claim 53 or 54,
The protection element, wherein the suction member is connected to a front surface and a rear surface of the soluble conductor, respectively. The method of claim 55,
A protective element in which each of the through holes faces each other through the soluble conductor in a pair of the suction members connected to the front and rear surfaces of the soluble conductor. The method of claim 53 or 54,
The through hole has a conductive layer formed on an inner circumferential surface to be continuous with the heating element lead electrode. The method of claim 57,
And a back electrode formed on a back surface of the first insulating substrate opposite to the surface,
The through hole is formed between the heating element lead electrode and the back electrode in the thickness direction of the first insulating substrate, and the conductive layer is connected to the heating element lead electrode and the rear electrode. The method of claim 53 or 54,
A protection element, wherein some or all of the through holes are filled with preliminary solder and/or flux. The method of claim 53 or 54,
The heating element is disposed on both sides of the through hole, the protection element. The method of claim 60,
A plurality of the through holes are formed,
The heating element is disposed on both sides of the plurality of through-holes, the protection element. The method of claim 53 or 54,
The soluble conductor is a protective element in which an inner layer is a low melting point metal and an outer layer is a coating structure of a high melting point metal. One or more battery cells,
A protection element connected on the charging/discharging path of the battery cell and blocking the charging/discharging path,
A current control element for controlling energization to the protection element by detecting a voltage value of the battery cell,
The protection element,
First and second external electrodes,
A soluble conductor connected between the first and second external electrodes,
It is connected to the soluble conductor, has a suction member for sucking the molten soluble conductor,
The suction member,
A first insulating substrate disposed between the first and second external electrodes,
A heating element formed on a surface of the first insulating substrate facing the fusible conductor,
An insulating member covering the heating element,
A heating element lead electrode connected to the heating element and formed on the surface of the first insulating substrate and connected to a part of the soluble conductor,
It is formed in the thickness direction of the first insulating substrate, and has a through hole continuous with the heating element lead electrode,
Having a plurality of the suction members,
The battery pack, wherein the soluble conductor is melted to block a current path between the first external electrode and the second external electrode.

Images