TWI603360B - Protection components, battery modules - Google Patents

Description

Protection component, battery module

The present invention relates to a protection element and a battery module for suppressing thermal runaway of a battery by fusing a current path to stop charging and discharging a battery connected to the current path.

Most rechargeable secondary batteries that are used in reverse are processed into battery packs and supplied to the user. In particular, in order to ensure the safety of users and electronic equipment, lithium ion secondary batteries having a high weight and energy density are generally provided in a battery pack in a plurality of protection circuits such as overcharge protection and overdischarge protection. The function of interrupting the output of the battery pack.

Such a protection element has an ON/OFF output using a FET switch built in the battery pack, thereby performing an overcharge protection or an overdischarge protection operation of the battery pack. However, in the case where the FET switch is short-circuited and damaged for some reason, or a large current flows instantaneously when a lightning surge or the like is applied, or the output voltage is abnormally lowered due to the life of the battery unit, or vice versa. In the case of abnormal voltage, the battery pack or electronic equipment must still be protected from accidents such as fire. Therefore, in order to safely interrupt the output of the battery unit in any of the above-mentioned abnormal states, a protection element composed of a fuse element having a function of interrupting the current path with an external signal is used.

As such a protective element suitable for a protection circuit for a lithium ion secondary battery or the like, as disclosed in Patent Document 1, a soluble conductor is connected between the first and second electrodes on the current path to form a part of the current path. The fusible conductor on the current path leads to itself by overcurrent The heat generating body or the heating element provided inside the protective element is blown. Such a protective element blocks the current path by collecting the molten liquid-like soluble conductor on the first and second electrodes.

Patent Document 1: Japanese Laid-Open Patent Publication No. 2010-003665

Patent Document 2: Japanese Laid-Open Patent Publication No. 2004-265617

In order to improve the insulation performance when the current path is interrupted, it is preferable to use the protective element of the above-mentioned fusible conductor to pull apart the distance between the first and second electrodes. However, as the electronic device is reduced in size and thickness, it is required to further reduce the size and thickness of the protective element built in the battery pack. Therefore, it is difficult to pull apart the distance between the first and second electrodes. Further, as the secondary battery has a higher capacity and a higher output, the rating of the protective element is also required to be larger.

Here, in order to increase the rating of the protection element, it is necessary to obtain a balance between the decrease in the conductor resistance of the fusible conductor and the insulation performance in the interruption of the current path. That is, in order to allow more current to flow, the conductor resistance must be lowered, so that the cross-sectional area of the fusible conductor must be increased. However, the larger the sectional area of the fusible conductor, the larger the amount of molten fusible conductor increases, and the time required for the fusion becomes longer, which may cause a safety impairment.

Accordingly, it is an object of the present invention to provide a protection element that increases the rated capacity of a fusible conductor and that can quickly fuse the fusible conductor, and a battery module in which the protection element is assembled.

In order to solve the above problems, the protective element of the present invention includes: an insulating substrate; a heating resistor formed on the insulating substrate; and an insulating member laminated on the insulating substrate to cover at least the heating resistor; the first and second electrodes, laminated The insulating substrate having the insulating member laminated thereon; the heating element extraction electrode is laminated on the insulating member to overlap the heating resistor, and is electrically connected to the heating resistor in a current path between the first and second electrodes Fusible conductor to Laminating the electrode from the heating element to the first and second electrodes, and causing a current path between the first electrode and the second electrode to be melted by heat; and covering the insulating substrate with a covering member; the fusible The conductor is formed at least in a central portion overlapping the heating element extraction electrode so as to be thicker than the fusion portion between the heating element extraction electrode and the first and second electrodes.

Further, the battery module of the present invention comprises: a battery comprising one or more rechargeable battery cells; a charge and discharge control circuit connected in series with the battery to control charging and discharging of the battery; and a protection element connected to the battery and a charge and discharge current path between the charge and discharge control circuits; a detection circuit for detecting a voltage value of each battery cell of the battery; and a current control element for controlling a current flowing to the protection element; the protection element having: an insulating substrate a heating resistor laminated on the insulating substrate; an insulating member laminated on the insulating substrate to cover at least the heating resistor; the first and second electrodes stacked on the insulating substrate in which the insulating member is laminated; and the heating element extraction electrode Laminating on the insulating member to overlap the heating resistor, electrically connecting the heating resistor to a current path between the first and second electrodes, and melting the conductor to extract an electrode from the heating element to the first 1 and a second electrode are laminated to fuse a current path between the first electrode and the second electrode by heat; and a covering member covers the insulating base The fusible conductor is formed at least in a central portion overlapping the heating element extraction electrode, and is thicker than a melting portion between the heating element extraction electrode and the first and second electrodes; the current control element is configured by the detection circuit When the voltage value of each of the detected battery cells is outside the predetermined range, the current is flown to the heating resistor body to control.

According to the present invention, by forming at least the central portion of the fusible conductor to be thick, the rating can be improved by lowering the resistance and the fusing characteristics can be favorably maintained at the same time, thereby achieving both the rise in rating and the maintenance of the fusing characteristics.

10‧‧‧Protection components

11‧‧‧Insert substrate

12‧‧‧ electrodes

13‧‧‧Solid conductor

13a‧‧‧Central Department

13b‧‧‧Fuse

13c‧‧‧ Both ends

14‧‧‧heating body

15‧‧‧Insulating components

16‧‧‧heating body extraction electrode

18‧‧‧Heating body electrode

19‧‧‧ Covering components

20‧‧‧Battery Pack

21~24‧‧‧ battery unit

26‧‧‧Detection circuit

27‧‧‧ Current control components

30‧‧‧Charge and discharge control circuit

31,32‧‧‧ Current control components

33‧‧‧Control Department

35‧‧‧Charging device

40‧‧‧Electrical materials

1A is a cross-sectional view showing a protective member to which the present invention is applied, and FIG. 1B is a plan view showing the covering member and the flux removed.

Figure 2 is a cross-sectional view for explaining a fuse portion of a fusible conductor.

Figure 3 is a cross-sectional view showing another protective element to which the present invention is applied.

Figure 4 is a cross-sectional view showing another protective element to which the present invention is applied.

Figure 5 is a cross-sectional view showing another protective element to which the present invention is applied.

Figure 6 is a circuit diagram showing a battery module.

Fig. 7 is a view showing the circuit configuration of the protection element.

Hereinafter, a protective element to which the present invention is applied and a battery module in which the protective element is assembled will be described in detail with reference to the drawings. The present invention is not limited to the embodiments described below, and various modifications can be made without departing from the spirit and scope of the invention. Moreover, the drawings are shown in a schematic manner, and there are cases where the ratio of each size is different from the reality. The specific dimensions and the like should be judged by the following instructions. Further, the drawings naturally contain portions having different dimensional relationships or ratios from each other.

(Composition of protective components)

As shown in FIG. 1, the protective element 10 to which the present invention is applied includes an insulating substrate 11, a heating resistor 14 laminated on the insulating substrate 11 and covered by the insulating member 15, and an electrode 12 (A1) formed at both ends of the insulating substrate 11. 12 (A2), the heating element extraction electrode 16 laminated on the insulating member 15 so as to overlap the heating resistor 14, and both ends of which are connected to the electrodes 12 (A1), 12 (A2) and connected to the heating element at the center portion The fusible conductor 13 of the electrode 16.

The insulating substrate 11 is formed into a substantially square shape using an insulating member such as alumina, glass ceramic, mullite, or zirconia. In addition to the insulating substrate 11, a material for a printed wiring board such as a glass epoxy substrate or a phenolic substrate may be used, but it is necessary to pay attention to the temperature at which the fuse is blown.

The heating resistor 14 is a conductive member having a high electric resistance value and generating heat when energized, and is made of, for example, W, Mo, Ru or the like. The alloy or the composition, the powder of the compound, the resin binder, and the like are mixed by a screen printing technique to form a paste, and a pattern is formed on the insulating substrate 11 and baked.

The insulating member 15 is disposed so as to cover the heating resistor 14, and the heating element extraction electrode 16 is disposed to face the heating resistor 14 via the insulating member 15. In order to efficiently transfer the heat of the heating resistor 14 to the fusible conductor, the insulating member 15 may be laminated between the heating resistor 14 and the insulating substrate 11.

One end of the heating element extraction electrode 16 is connected to the heating element electrode 18 (P1). Further, the other end of the heating resistor 14 is connected to the other heating element electrode 18 (P2).

The fusible conductor 13 is made of a low-melting-point metal which is rapidly melted by the heat generation of the heating resistor 14, and for example, a solder containing Pb as a main component and a Pb-free solder containing Sn as a main component can be preferably used. Further, the meltable conductor 13 may be a laminate of a low melting point metal and a high melting point metal such as Ag, Cu or an alloy containing the like as a main component.

When the protective element 10 is reflowed by laminating the high melting point metal and the low melting point metal, the reflow temperature exceeds the melting temperature of the low melting point metal layer, and even if the low melting point metal layer is melted, the fusible conductor 13 does not become Fuse. The above-mentioned fusible conductor 13 can also be formed by forming a low melting point metal into a high melting point metal by using a plating technique, by using other well-known layering techniques. It is also possible to form a film or a film formation technique. Further, the fusible conductor 13 can be connected to the heat generating body lead electrode 16 and the electrodes 12 (A1), 12 (A2) using the low melting point metal solder constituting the outer layer.

Further, the protective element 10 may be coated with the flux 17 on the soluble conductor 13 in order to prevent oxidation of the outer layer of the low-melting-point metal layer 13b. Further, in order to protect the inside of the protective element 10, the covering member 19 is placed on the insulating substrate 11.

(fuse part, center part, both ends)

As shown in Fig. 1, the soluble conductor 13 to which the present invention is applied has a substantially plate shape, and is connected between the first and second electrodes 12 (A1) and 12 (A2) through the heating element extraction electrode 16. Further, the meltable conductor 13 and the central portion 13a overlapping the heating element extraction electrode 16 are formed thicker than the fuse portion 13b between the heating element extraction electrode 16 and the first and second electrodes 12 (A1) and 12 (A2).

Here, the central portion 13a of the soluble conductor 13 is overlapped with the heating element extraction electrode 16, and is connected to the middle of the long side direction of the fusible conductor 13 between the first and second electrodes 12 (A1) and 12 (A2). section.

Further, the soluble conductor 13 is connected between the heating element lead-out electrode 16 and the electrodes 12 (A1) and 12 (A2), and the self-heating (Joule heat) due to an overcurrent or the heat fusion of the heating resistor 14 causes the heating element to be taken out. The electrode 16 is fused between the electrodes 12 (A1) and 12 (A2). Thereby, the protection element 13 blocks the current path.

As shown in FIG. 2, the fuse portion 13b of the fusible conductor 13 is a fuse portion of the fusible conductor 13 connected between the heat generating body lead electrode 16 and the electrodes 12 (A1), 12 (A2), specifically, It means between the heating element extraction electrode 16 and the electrode 12 (A1), and between the heating element extraction electrode 16 and the electrode 12 (A2).

The central portion 13a is formed thicker than the fuse portion 13b, and the soluble conductor 13 is conducive The resistance is reduced and the rating of the protection element 10 is raised. Further, since the fuse portion 13b of the meltable conductor 13 is formed thin as in the related art, the fuse characteristics between the heat generating body lead electrode 16 and the electrodes 12 (A1) and 12 (A2) can be favorably maintained.

(Modification 1)

It is preferable that the soluble conductor 13 is formed to be thicker than the fuse portion 13b at both end portions 13c overlapping the first and second electrodes 12 (A1) and 12 (A2). By forming the both end portions 13c thick, the fusible conductor 13 can further reduce the resistance and increase the rating of the protective element 10. Moreover, in this case, since the fuse portion 13b of the soluble conductor 13 is also formed thin as in the related art, the fusing characteristics between the heat generating body lead electrode 16 and the electrodes 12 (A1) and 12 (A2) can be favorably maintained.

(Modification 2)

Further, in the fusible conductor 13, it is preferable that the central portion 13a or both end portions 13c are formed to be thicker by being protruded upward by the covering member 19. The flux 17 can be held on the central portion 13a by projecting from the central portion 13a of the fusible conductor 13 toward the covering member 19 side.

That is, the fusible conductor 13 is provided with a flux 17 on the upper surface opposed to the covering member 19 to prevent oxidation of the fusible conductor 13 and to rapidly wet the molten conductor during heating. In order to fuse the meltable conductor 13 of the two fuse portions 13b, the flux 17 is preferably held in the central portion 13a between the fuse portions 13b. Further, the meltable conductor 13 protrudes toward the covering member 19 side by the central portion 13a, and the flux 17 can be surely held in the central portion 13a. Further, the meltable conductor 13 can be formed into a triangular cross section, a trapezoidal cross section, a cylindrical shape, a hollow cylindrical shape, or the like as long as the central portion 13a protrudes upward from the fuse portion.

Further, the central portion 13a or both end portions 13c of the soluble conductor 13 may be protruded toward the lower surface side opposite to the upper surface on which the covering member 19 faces. In this case, I can't expect the center. The flux 17 of the portion 13a maintains the effect, but it is possible to reduce the resistance due to the formation of a thicker portion. Further, the central portion 13a or both end portions 13c of the soluble conductor 13 may be protruded toward the upper surface of the cover member 19 and the lower surface of the opposite side.

(Method 1)

The meltable conductor 13 can be produced by press working or cutting a plate-shaped low melting point metal into the above-described predetermined shape. Further, the fusible conductor 13 can be produced by casting a plate-shaped low-melting-point metal into a predetermined shape and using another known manufacturing method.

(Method 2)

Further, as shown in FIG. 3, the fusible conductor 13 may be formed thicker by laminating the conductive material 40 at the central portion 13a or both end portions 13c. The conductive material 40 is formed, for example, by plating or a laminated metal foil. Although the number of layers of the conductive material 40 is not limited, it is possible to prevent the deterioration of the fusible conductor 13 caused by the protective element 10 over a period of time, and the reliability can be improved.

(Modification 3)

Further, the conductive material 40 may be a metal having a lower melting point than the soluble conductor 13. The fusible conductor 13 is melted by the etching action of the low melting point metal at the time of blowing by applying a low melting point metal, and the current path can be more quickly interrupted.

(Method 3)

Further, as shown in FIG. 4, the soluble conductor 13 may be formed by coating a metal paste such as a layer of a silver paste or a gold paste or a solder paste or the like as a conductive material 40 in the central portion 13a or both end portions 13c. . According to this production method, it is possible to apply only a metal paste or the like to the meltable conductor 13 to achieve thickening, and the meltable conductor 13 can be manufactured in a simple procedure. Further, at this time, as the conductive material 40, a metal having a lower melting point than the soluble conductor 13 may be used.

(Method 4)

Further, as shown in FIG. 5, the fusible conductor 13 may have pores 41 formed inside the thick central portion 13a or both end portions 13c. When the solder paste is applied to the first and second electrodes 12 (A1) and 12 (A2) of the insulating substrate 11, the components of the organic substance in the paste are vaporized at a high temperature such as the reflow step, and the soluble conductor is formed. The pores 41 are formed between the heat generating body lead electrode 16 or the electrodes 12 (A1) and 12 (A2). The fusible conductor 13 is easily deformed at a high temperature, and if the pores 41 are formed, the formation portion of the pores 41 protrudes upward correspondingly.

According to this soluble conductor 13, the center portion 13a protrudes toward the covering member 19 side, and the flux 17 can be held on the center portion 13a. Further, the fusible conductor 13 does not require a special step of forming the central portion 13a to be thick, and the central portion 13a can be formed thicker by a known procedure.

(How to use the protection component)

As shown in FIG. 6, the above protective element 10 is used in a circuit in a battery pack 20 of a lithium ion secondary battery.

For example, the protective element 10 is assembled and used in a battery pack 20 having a battery stack 25 composed of battery cells 21 to 24 of a total of four lithium ion secondary batteries.

The battery pack 20 includes a battery stack 25, a charge and discharge control circuit 30 for controlling charge and discharge of the battery stack 25, a protective element 10 applicable to the present invention when the battery stack 25 is abnormally interrupted, and a voltage for detecting each of the battery cells 21-24. The detection circuit 36 and the current control element 27 that controls the operation of the protection element 10 in accordance with the detection result of the detection circuit 26.

The battery stack 25 is connected in series to the battery cells 21 to 24 for protecting against the influence of overcharge and overdischarge conditions, and is detachably connected to the charging device through the positive terminal 20a and the negative terminal 20b of the battery pack 20. 35, applying charging power from the charging device 35 Pressure. The positive electrode terminal 20a and the negative electrode terminal 20b of the battery pack 20 charged by the charging device 35 are connected to an electronic device that operates with a battery, whereby the electronic device can be operated.

The charge and discharge control circuit 30 includes two current control elements 31 and 32 connected in series to a current path flowing from the battery stack 25 to the charging device 35, and a control unit 33 that controls the operation of the current control elements 31 and 32. The current control elements 31, 32 are constituted by, for example, field effect transistors (hereinafter referred to as FETs), and the gate voltage is controlled by the control unit 43, thereby controlling the conduction and blocking of the current path of the battery stack 25. The control unit 33 receives the power supply from the charging device 35 and operates, and controls the operation of the current control elements 31 and 32 to interrupt the current path when the battery stack 25 is overdischarged or overcharged based on the detection result of the detection circuit 26.

The protection element 10 is, for example, connected to a charge and discharge current path between the battery stack 25 and the charge and discharge control circuit 30, the operation of which is controlled by the current control element 27.

The detection circuit 26 is connected to each of the battery cells 21 to 24, detects the voltage values of the battery cells 21 to 24, and supplies the respective voltage values to the control unit 33 of the charge and discharge control circuit 30. Further, the detection circuit 26 outputs a control signal for controlling the current control element 27 when any one of the battery cells 21 to 24 is an overcharge voltage or an overdischarge voltage.

The current control element 27 is composed of, for example, an FET. When the voltage value of the battery cells 21 to 24 exceeds a predetermined over-discharge or over-charge state by the detection signal output from the detection circuit 26, the protection element 10 is operated and controlled. The charge and discharge current paths of the battery stack 25 are not interrupted by the switching action of the current control elements 31, 32.

In the battery pack 20 configured as above, the protective element 10 to which the present invention is applied has the circuit configuration shown in FIG. That is, the protective element 10 is made of a fusible conductor 13 connected in series through the heat generating body lead-out electrode 16 and is heated by a connection point through the fusible conductor 13 to melt the fusible conductor 13 The circuit structure formed by the heating resistor 14 is melted. Further, in the protective element 10, for example, the fusible conductor 13 is connected in series to the charge and discharge current path, and the heating resistor 14 is connected to the current control element 27. One of the two electrodes 12 of the protection element 10 is connected to A1 and the other is connected to A2. Further, the heating element extraction electrode 16 is connected to P1 to the heating element electrode 18 connected thereto, and the other heating element electrode 18 is connected to P2.

The protective element 10 composed of the above-described circuit can reliably fuse the fusible conductor 13 on the current path by the heat generated by the heating resistor 14.

Further, the protective element of the present invention is not limited to the case of a battery pack for a lithium ion secondary battery, and can of course be applied to various uses in which a current path of an electric signal must be interrupted.

(Example)

Next, an embodiment of the present invention will be described. In the present embodiment, the protective element 10 using the fusible conductor 13 and the protective element using the conventional fusible conductor, which are applicable to the invention, are used to measure and evaluate the resistance value of each of the fusible conductors, the retention of the flux, and the heat blown. time.

In the examples and the comparative examples, an alumina ceramic substrate (thickness: 0.5 mm) of 6 mm × 4 mm was used as an insulating substrate, and after printing Ag-Pd paste on the surface, the first and second electrodes and a pair were formed by firing at 850 ° C for 30 minutes. The heating body electrode and the heating element lead electrode. Further, a yttria-based resistor paste was printed between the first and second electrodes, and baked at 850 ° C for 30 minutes to form a heating resistor. The pattern resistance of the heating resistor is 1 Ω.

The fusible conductors of the examples and the comparative examples were all Sn:Sb=95:5, and formed into a 1 mm×5 mm melting point at 240° C., and a connection pattern paste having a melting point of 219° C. (Sn/Ag/Cu=96.5/3/0.5) ) is connected to the first and second electrodes and the heating element extraction electrode.

The fusible conductive system of the first embodiment is formed into a heating element by press working The thickness of the central portion of the pole and the end portions of the first and second electrodes is 0.15 mm, the thickness of the fuse portion between the first electrode and the heating element extraction electrode, and between the second electrode and the heating element extraction electrode. It is 0.10mm.

The fusible conductor of the second embodiment is the same as the first embodiment except that the thickness of the central portion and both end portions is 0.13 mm.

The fusible conductor of the third embodiment is the same as that of the first embodiment except that the thickness of the central portion and both end portions is 0.12 mm.

The fusible conductor of the fourth embodiment is the same as that of the first embodiment except that the thickness of the central portion and both end portions is 0.11 mm.

The fusible conductor of the fifth embodiment has a metal foil (Sn/Ag/Cu=96.5/3.0/0.5) having a thickness of 0.05 mm formed by a metal having a lower melting point than the fusible conductor at a central portion and both end portions, and has a thickness of 0.15 mm. The fuse portion is 0.10 mm.

The fusible conductor of Example 6 was coated with a metal paste (Sn/Ag/Cu = 96.5 / 3.0 / 0.5) at a thickness of 0.05 mm at the center portion and both end portions, and was fired to have a thickness of 0.15 mm, and the fuse portion was 0.10 mm. .

The fusible conductor of Example 7 was placed between the first and second electrodes, and then heated at 220 ° C for 2 minutes in an oven to produce a pore having a diameter of 0.05 mm in the center portion and both end portions to have a thickness of 0.15. Mm, the fuse portion is 0.10 mm.

In the fusible conductive system of Comparative Example 1, a flat structure in which the center portion, both end portions, and the fuse portion were 0.10 mm was used.

In the fusible conductive system of Comparative Example 2, a flat structure in which the center portion, both end portions, and the fuse portion were 0.15 mm was used.

The resistance values of the fusible conductors of the above examples and comparative examples, the retention of the flux, and the heating fusing time were measured and evaluated. Regarding the flux retention of the fusible conductor, 100 protective elements of the examples and the comparative examples were respectively manufactured, and after removing the covering member, it was judged that the flux stayed near the center portion or flowed to one of the left or the other of the fusible conductor or the other side. Or both parties. The heat-fusing time of the fusible conductor of the examples and the comparative examples is the time from when the heating resistor of 3 W is energized to cause heat generation until the fuse portion is blown.

As shown in Table 1, in each of the examples, since the central portion and both end portions of the fusible conductor were formed thick, the resistance value of the fusible conductor can be lowered. Also, in various embodiments, the flux remains In the vicinity of the center portion, no flux flow to the left and right is generated. Furthermore, in each of the embodiments, the fusing time can be shortened.

On the other hand, in the fusible conductor of Comparative Example 1, since the center portion, both end portions, and the fuse portion were formed to have the same thickness (0.10 mm), the resistance value was as high as 20 m Ω, and it was difficult to raise the rating as the protection element. Further, since the thick central portion was not provided, the flux applied to the meltable conductor flowed to 10% of the protective member of Comparative Example 1.

In the fusible conductor of Comparative Example 2, the central portion, both end portions, and the fuse portion were formed to have the same thickness (0.15 mm). Therefore, the resistance value was as low as 10 m Ω, but conversely, the heating fusing time became longer than 40 seconds. Further, in Comparative Example 2, since the thick central portion was not provided, the flux applied to the meltable conductor flowed to 5% of the protective member.

As described above, the meltable conductor can be made thicker at least at the center portion, and can achieve both the rated lift and the blown characteristics due to the low resistance.

As shown in the first to fourth embodiments, when the thickness of the central portion and both end portions is reduced, the resistance value of the meltable conductor is increased, but the fusing time is shortened. Further, as shown in Example 4, as long as the central portion was formed to be 0.01 mm thicker than the melted portion, the flow of the flux was suppressed as compared with Comparative Example 1.

According to the fifth embodiment, by laminating a metal foil composed of a metal having a lower melting point than the fusible conductor, the heating fusing time can be shortened as compared with the first embodiment. The reason for this is that the low melting point metal erodes the fusible conductor.

In the sixth embodiment, the metal paste flows more or less toward the fuse portion side, and it is difficult to maintain the shape, and the resistance value is somewhat increased. Further, as the metal paste, the heat fusing time can be shortened by using a metal having a lower melting point than the fusible conductor.

In the seventh embodiment, since the pores are present inside, the resistance cannot be lowered, but The flow of the flux can be suppressed, and the heating and melting time is also shortened.

10‧‧‧Protection components

11‧‧‧Insert substrate

12 (A1), 12 (A2) ‧ ‧ electrodes

13‧‧‧Solid conductor

13a‧‧‧Central Department

13b‧‧‧Fuse

13c‧‧‧ Both ends

14‧‧‧heating body

15‧‧‧Insulating components

16‧‧‧heating body extraction electrode

17‧‧‧ Flux

18 (P1), 18 (P2) ‧ ‧ heating body electrode

19‧‧‧ Covering components

Claims (8)

A protective element comprising: an insulating substrate; a heating resistor formed on the insulating substrate; and an insulating member laminated on the insulating substrate so as to cover at least the heating resistor; and the first and second electrodes are laminated on the insulating layer The insulating substrate of the member; the heating element extraction electrode is laminated on the insulating member so as to overlap the heating resistor, and is electrically connected to the heating resistor in a current path between the first electrode and the second electrode; The conductor is laminated so that the electrode from the heating element extends across the first and second electrodes, and the current path between the first electrode and the second electrode is melted by heat; and the covering member covers the insulating substrate The fusible conductor is formed at least in a central portion overlapping the heat generating body lead-out electrode, and is thicker than a fuse portion between the heat generating body lead-out electrode and the first and second electrodes. The protective element according to claim 1, wherein the soluble conductor has both end portions overlapping the first and second electrodes formed between the heating element extraction electrode and the first and second electrodes. The fuse is thick. The protective member of claim 1 or 2, wherein the central portion of the fusible conductor protrudes toward the covering member side and holds the flux. The protective element of claim 1 or 2, wherein the fusible conductive system is formed thicker by laminating a conductive material at the central portion and/or the both end portions. The protective element of claim 4, wherein the conductive material has a lower melting point than the fusible conductor. The protective element of claim 1 or 2, wherein the fusible conductive system is formed thick by applying a conductive paste to the central portion and/or the both end portions. The protective member of claim 1 or 2, wherein the fusible conductor has an void in the inner portion and/or the inner portion of the both ends. A battery module comprising: a battery, consisting of more than one rechargeable battery unit; a charge and discharge control circuit connected in series with the battery to control charging and discharging of the battery; a protection component connected to the battery and the charge and discharge control a charging and discharging current path between the circuits; a detecting circuit for detecting a voltage value of each battery cell of the battery; and a current control element for controlling a current flowing to the protective element; the protective element having: an insulating substrate; a heating resistor Laminating the insulating substrate; the insulating member is laminated on the insulating substrate so as to cover at least the heating resistor; the first and second electrodes are laminated on the insulating substrate on which the insulating member is laminated; and the heating element leads to the electrode Laminating the insulating member so as to overlap the heating resistor, electrically connecting the heating resistor to a current path between the first and second electrodes; and melting the conductor to lead the electrode from the heating element The first and second electrodes are laminated to fuse the current path between the first electrode and the second electrode by heat; and the covering member covers the layer On an insulating substrate; the fusible conductor, at least the central portion of the heat generating element overlap to form the lead electrodes than the heating a fuse portion between the body lead electrode and the first electrode and the second electrode; wherein the current control element causes a current to flow to the heat generating resistor when a voltage value of each of the battery cells detected by the detecting circuit is outside a predetermined range Way to control.