CN112514025A

CN112514025A - Conductive plate and battery device

Info

Publication number: CN112514025A
Application number: CN201980050528.0A
Authority: CN
Inventors: 吉泽规次; 二瓶裕胜
Original assignee: Murata Manufacturing Co Ltd
Current assignee: Murata Manufacturing Co Ltd
Priority date: 2018-07-31
Filing date: 2019-07-16
Publication date: 2021-03-16
Also published as: JPWO2020026789A1; WO2020026789A1; JP7052871B2

Abstract

A conductive plate has an energizing path between a current input region and a current output region, the energizing path being fused when an overcurrent flows, the energizing path including a plurality of current paths having different resistance values.

Description

Conductive plate and battery device

Technical Field

The present invention relates to a conductive plate for connecting electrodes of a plurality of batteries, for example, and a battery device having a plurality of batteries connected by the conductive plate.

Background

In recent years, the use of secondary batteries such as lithium ion batteries has been rapidly expanding to electric power storage devices for storing electric power, automobile storage batteries, and the like combined with new energy systems such as solar cells, wind power generation, and the like. In order to provide for these applications, an assembled battery device is used in which a plurality of unit cells (also referred to as cells or battery units) are connected in series or in parallel. In order to electrically and mechanically connect the plurality of batteries, a conductive plate is used. As a further function, it has been proposed to provide the conductive plate with a fuse function for overcurrent protection (see patent documents 1 and 2).

Patent document 1 describes a plate-shaped fuse for connecting end electrodes of a battery. As shown in fig. 14, the fuse 101 is configured such that a connecting portion between batteries is formed as a narrow blowout portion 102, and the blowout portion 102 blows when an overcurrent flows.

Patent document 2 discloses a fuse 103 as shown in fig. 15. The long plate-like member of the fuse 103 is bent, and the fuse 103 has a connecting portion 103a and a main body portion 103 b. The main body portion 103b is joined to the end face of the single cell held inside by spot welding. A slit extending in the width direction is formed in the fuse link 103. The outside of the slit is covered by the hood 104 of the battery holder. The narrow portions formed on both sides of the slit become fusible portions. In the fuse 103, in the case where an overcurrent of a certain level or more flows, the fusible part is fused, thereby securing the safety of the battery pack.

Documents of the prior art

Patent document

Patent document 1: japanese laid-open patent publication No. 2000-311575

Patent document 2: japanese unexamined patent publication No. 2012-028007

Disclosure of Invention

Technical problem to be solved by the invention

The technique described in patent document 1 has a problem that the mechanical strength is insufficient when the batteries are connected to each other because the width of the fusing portion 102 is narrow. If the width of the fusing portion 102 is increased, the cross-sectional area increases, the resistance value decreases, and the amount of heat generation decreases. As a result, the time for fusing becomes long, or fusing by an assumed overcurrent becomes impossible, and therefore it is difficult to widen the width of fusing portion 102. The technique described in patent document 2 has a problem that the mechanical strength of the portion where the slit is formed is weakened because the fusible portion is provided on both sides of the short side of the slit.

Accordingly, an object of the present invention is to provide a conductive plate and a battery device, which have a short time required for fusing and can ensure mechanical strength.

Technical solution for solving technical problem

The present invention relates to a conductive plate having an electrical path between a current input region and a current output region, the electrical path being fused when an overcurrent flows, the electrical path including a plurality of current paths having different resistance values.

The present invention also relates to a battery device in which electrodes of a plurality of batteries are electrically and mechanically connected to each other via a conductive plate, the conductive plate having an electrical path between a current input region and a current output region, the electrical path including a plurality of current paths having different resistance values, and the electrical path being fused when an overcurrent flows.

Effects of the invention

According to at least one embodiment, the time required for fusing is short and mechanical strength can be ensured. The effects described herein are not necessarily limited, and may be any effects described in the present disclosure or effects different from them in nature.

Drawings

Fig. 1 is a perspective view of an example of a battery pack device to which the present invention can be applied.

Fig. 2a and 2B are a plan view and a bottom view for explaining connection between batteries in the battery assembly.

Fig. 3 is a connection diagram showing electrical connection of the battery pack device.

Fig. 4 is a perspective view of a connection electrode as a conductive plate according to a first embodiment of the present invention.

Fig. 5 is a side view showing a portion of the connection electrode of the battery pack apparatus.

Fig. 6 is a partial side view showing a fuse region formed in the connection electrode.

Fig. 7 is a connection diagram showing an equivalent circuit of the fuse region.

Fig. 8 is a diagram for explaining a blowing process of the fuse region.

Fig. 9 is a diagram for explaining a blowing process of the fuse region.

Fig. 10 is a partial side view for explaining a second embodiment of the present invention.

Fig. 11 is a connection diagram of an equivalent circuit of the fuse region of the second embodiment.

Fig. 12 is a diagram for explaining a blowing process of the fuse region.

Fig. 13 is a perspective view for explaining another example of the fuse region.

Fig. 14 is a perspective view of an example of a conventional conductive plate.

Fig. 15 is a perspective view of another example of a conventional conductive plate.

Detailed Description

The present invention will be described below with reference to the accompanying drawings.

The embodiments and the like described below are preferable specific examples of the present invention, and the contents of the present invention are not limited to these embodiments and the like. The effects described in the present specification are merely exemplary and not restrictive, and there are no objections to the contrary.

First, a first embodiment of the present invention will be explained. A battery device, such as a battery pack device, to which the present invention is applicable is shown in fig. 1. Fig. 2a shows an outline of an end portion of the upper surface of the battery pack apparatus, and fig. 2B shows an outline of an end portion of the lower surface of the battery pack apparatus. The battery pack device accommodates a plurality of cells, for example, 64 cells in a battery pack holder 1 made of synthetic resin, and connects the plurality of cells to each other via 9 connection electrodes T1, T3, T5, … …, and T17, which are conductive plates disposed on the upper surface, and 8 connection electrodes T2, T4, T6, … …, and T16, which are conductive plates disposed on the lower surface. In fig. 2a and 2B, the connection electrodes T1 to T17 are indicated by two-dot chain lines.

The 64 batteries are, for example, cylindrical lithium ion secondary batteries. In addition to lithium ion batteries, all other rechargeable secondary batteries such as nickel hydrogen batteries, nickel cadmium batteries, lithium polymer batteries, etc. may be used. Further, the battery is not limited to the cylindrical battery, and may be a prismatic battery. The connection electrode is a plate-like body made of a conductive material such as a metal, for example, copper, a copper alloy, or the like.

The arrangement of 16 cells extending in the lateral direction in fig. 2a and 2B is such that 4 cells are stacked in the longitudinal direction. The positive and negative polarities of the cells adjacent to each other in the row direction are reversed, and the positive and negative polarities of the cells are in the same relationship between the rows. The polarities presented to the upper surface sides of the 4 cells located in the longitudinal direction of the positive electrode side end shown in a of fig. 2 are the same (+). The positive electrodes of the longitudinal 4 cells C1, C2, C3 and C4 are electrically and mechanically connected by welding such as projection welding through the connection electrode T1 of the upper surface. In addition, the negative electrode of the adjacent 8 cells C11, C12, C13 and C14 and the positive electrode of the cells C21, C22, C23 and C24 are electrically and mechanically connected by the connection electrode T3 on the upper surface, for example, by projection welding.

At the end portion on the lower surface side, as shown in B of fig. 2, the negative electrode of the adjacent 8 cells C1, C2, C3, and C4 and the positive electrode of the cells C11, C12, C13, and C14 are electrically and mechanically connected by projection welding through a connection electrode T2. Further, the negative electrode of the adjacent 8 cells C21, C22, C23 and C24 and the positive electrode of the cells C31, C32, C33 and C34 are electrically and mechanically connected by projection welding through the connection electrode T4.

In this manner, the electrodes of the cells are connected by the connection electrodes T1 to T17, and a battery device of "4 parallel 16 series" is configured as shown in fig. 3. The positive power cable 2+ is connected to the connection electrode T1 connected to the positive electrodes of the batteries C1 to C4, and the negative power cable 2-is connected to the connection electrode T17 connected to the negative electrodes of the batteries C71 to C74. As a modification of the above configuration, a "2 parallel 32 series" battery pack device may be configured.

Although not shown in fig. 1, one control board is mounted so as to face the side surface of the battery pack holder 1. A circuit for controlling the battery pack device is mounted in the control substrate. As shown in fig. 1, lead portions L1 to L17 for connection are provided integrally with the connection electrodes T1 to T17, respectively, and the tips of the lead portions L1 to L17 are soldered to predetermined connection portions of the control board.

The battery pack device is housed in the outer case. Although not shown, the outer case is a metal box-shaped case. The outer case is not limited to being made of metal, and may be made of resin, for example.

In the present invention, as will be described later, the positive connection electrode T1 and the negative connection electrode T17 have a fuse function. Therefore, in the equivalent circuit of fig. 3, fuses are inserted on the positive electrode side and the negative electrode side, respectively. These fuses are cut off when overcurrent flows into the battery pack device to protect the battery of the battery pack device. For example, an overcurrent flows in the case of a short circuit of a load. It is sufficient to provide a fuse on at least one of the positive electrode side and the negative electrode side.

Fig. 4 shows a connection electrode T17 having a fuse function on the negative electrode side. Connection electrode T17 is formed by bending a metal plate such as copper so as to have upper surface 11b and side surface 12b having an opening angle of substantially 90 °. On the upper surface 11b, for example, welding regions 13b each formed of a projection or a recess for welding each electrode of 4 batteries are formed. As a method of welding, for example, projection welding is used. Other welding methods may also be used. Further, lead portion L17 is led out from upper surface 11 b. The connection electrode T17 connects 4 cells C71 to C74 (see fig. 3) in parallel.

A circular opening 14b for attaching the end of the negative-side power cable 2-is formed in the side surface 12 b. A slit 15b is formed in the side surface 12b in parallel with the folded edge. A slit 16b perpendicular to the bent edge is formed at a position spaced apart from the closed end side of the slit 15b by a predetermined distance. Further, a portion continuous with the slit 16b and substantially parallel to the folded edge and a slit 17b bent so as to be distant from the folded edge are formed.

The side surface 12b is divided into two

regions

18b and 19b by the

slits

16b and 17 b. In addition,

current input regions

20b and 21b and

current output regions

22b and 23b of each region are defined by the slit 15b, the slit 16b, and the slit 17 b. That is, the current input region 20b and the current output region 22b constitute a first current path group, and the current input region 21b and the current output region 23b constitute a second current path group. These current path groups are bent into a substantially inverted L-shape.

Current flows from the outside into the battery pack apparatus through the negative-electrode-side power cable 2- (opening 14b) and the connection electrode T17. In a region 18b of the side face 12b of the connection electrode T17, a current flows from the current input region 20b to the current output region 22b, and a current flows from the current input region 21b to the current output region 23 b. These two current-carrying paths include

fuse regions

24b and 25b, respectively. Each of the

fuse regions

24b and 25b is a region in which a plurality of striped current paths having different lengths are formed in parallel.

Fig. 5 shows a side surface of the connection electrode T1 attached to the positive electrode side of the battery pack device. The connection electrode T1 has the same structure as the negative connection electrode T17. Connection electrode T1 is formed by bending a metal plate such as copper so as to have upper surface 11a and side surface 12a having an opening angle of substantially 90 °. On the upper surface 11a, for example, welding regions each formed of a projection or a recess for welding each electrode of 4 cells are formed.

The connection electrode T1 connects 4 cells C1 to C4 (see fig. 3) in parallel. In the connection electrodes T1 and T17, the

upper surfaces

11a and 11b on which the welding regions 13a and 13b are formed are surfaces to be pressed at the time of welding, and thus require mechanical strength. Therefore, it is not preferable to form the fuse regions on the

upper surfaces

11a and 11b because the mechanical strength is reduced, and the fuse regions are formed on the side surfaces 12a and 12 b.

A circular opening 14a for attaching the end of the positive-side power cable 2+ is formed in the side surface 12 a. A slit 15a is formed in the side surface 12a in parallel with the folded edge. A slit 16a perpendicular to the bent edge is formed at a position spaced apart from the closed end side of the slit 15a by a predetermined distance. Further, a portion continuous with the slit 16a and substantially parallel to the folded edge and a slit 17a bent so as to be distant from the folded edge are formed.

The side surface 12a is divided into two

regions

18a and 19a by the

slits

16a and 17 a. In addition,

current input regions

20a and 21a and

current output regions

22a and 23a of the respective regions are defined by the slit 15a and the slit 16 a. That is, the current input region 20a and the current output region 22a constitute a first current path group, and the current input region 21a and the current output region 23a constitute a second current path group. These current path groups are bent into a substantially inverted L-shape.

Current is output from the battery pack device to the outside through the connection electrode T1 and the positive-side power cable 2+ (opening 14 a). In a region 18a of the side face 12a of the connection electrode T1, a current flows from the current input region 20a to the current output region 22a, and a current flows from the current input region 21a to the current output region 23 a. These two current-carrying paths include

fuse regions

24a and 25a, respectively. Each of the

fuse regions

24a and 25a is a region in which a plurality of striped current paths having different lengths are formed in parallel.

The

fuse regions

24a and 25a are explained with reference to fig. 6. The

fuse regions

24b and 25b formed in the connection electrode T17 have the same configuration as the

fuse regions

24a and 24 b.

The fuse region 24a is formed in a region sandwiched between the

slits

15a and 17 a. By forming 6 slits parallel to the

slits

15a and 17a and having the same width, 7 current paths P1, P2, P3, P4, P5, P6, and P7 having the same width (for example, approximately 1mm) and different lengths are formed. The current paths P1 to P7 are aligned at one end, and the lengths thereof are increased in order from the uppermost current path P1 to the current path P7.

The fuse region 25a is formed in a region sandwiched between the slit 17a and the lower side edge of the side face 12 a. By forming 6 slits parallel to the slit 17a and having the same width, 7 current paths P8, P9, P10, P11, P12, P13, and P14 in stripe shapes having the same width and different lengths are formed. The current paths P8 to P14 are aligned at one end, and the lengths thereof are increased in order from the uppermost current path P8 to the current path P14. The width, length, and/or number of current paths in the

fuse regions

24a and 25a are set to appropriate values in consideration of the value of the current to be blown, the ease of processing, and the like. Further, the width, length, and/or number of

fuse regions

24a and 25a may be different from each other.

An equivalent circuit of the connection electrode T1 is shown in fig. 7. The resistance values of the current paths P1 to P14 are represented by R1 to R14. The resistance values of the current input region 20a and the current output region 22a for the fuse region 24a are represented by R20a and R22a, and the resistance values of the current input region 21a and the current output region 23a for the fuse region 25a are represented by R21a and R23 a.

The resistance value of each current path is proportional to the length and inversely proportional to the cross-sectional area. In this example, since the thickness of the connection electrode T1 is constant and the widths are equal, the cross-sectional areas of the current paths are equal. In each fuse region, the lengths of the current paths are in a relationship of (P1 < P2 < P3 < P4 < P5 < P6 < P7), (P8 < P9 < P10 < P11 < P12 < P13 < P14). Therefore, there are relationships (R1 < R2 < R3 < R4 < R5 < R6 < R7), (R8 < R9 < R10 < R11 < R12 < R13 < R14). Further, the combined resistance values of the resistance values R1 to R7 and the combined resistance values of the resistance values R8 to R14 are not extremely different values, and the combined resistance values of the resistance values R1 to R7 are, for example, values slightly smaller than the combined resistance values of the resistance values R8 to R14.

The current input region 20a for the fuse region 24a has a short circuit length from the bent edge of the connection electrode T1 as the current supply position. The current output region 22a of the fuse region 24a has a short circuit length up to the position (opening 14a) of the positive power cable 2+ as the current output position. These circuit lengths in the case of the fuse region 25a are longer than those in the case of the fuse region 24 a. Therefore, (R20a < R21a) and (R22a < R23a) are in the relationship.

The resistance values R20a to R23a are resistance values of current paths having a wide width and a large cross-sectional area, and are therefore smaller than the resistance values R1 to R14 of the stripe-shaped current paths. In order to make the resistance values of the current paths (circuit lengths) for the respective fuse regions in the above-described relationship, not only the lengths of the paths but also the widths of the paths may be adjusted. Furthermore, the magnitude relation of the resistance value is (R20a + R22a) < (R21a + R23 a). Further, in the

fuse regions

24a and 25a, the resistance values are made different by making the lengths of the respective current paths different, but the resistance values may be made different by the elements of the circuit length between the end of each current path and the current supply position and/or the current output position.

The

fuse regions

24a and 25a are formed on the + side connection electrode T1, and the

fuse regions

24b and 25b formed on the-side connection electrode T17 have the same magnitude relationship of resistance values. However, it is sufficient to provide a fuse region in at least one of the connection electrodes T1 and T17.

When a current (overcurrent) equal to or larger than a predetermined value flows into the battery pack device, the

fuse regions

24a and 24b and 25a and 25b are fused to protect the battery pack device. The fusing process with respect to the connection electrode T1 is a process in the following order. The same applies to the fusing process of the connection electrode T17.

1. An overcurrent is generated due to an external short circuit or the like.

2. Since the relationship of the resistance value is (R20a + R22a) < (R21a + R23a), more current flows on the fuse region 24a side than on the fuse region 25a side. As an example, about 80% of the total current flows to the fuse region 24a side.

3. In the fuse region 24a, the most current flows in the current path P1 having the smallest resistance value, and therefore the current path P1 is blown by joule heat first.

4. Then, the most current flows through the current path P2 having a small resistance value, and the current path P2 melts. Hereinafter, the current path is blown in the order of P3 → P4 → … … → P7.

5. When all the current paths of the fuse region 24a are blown, the current flows concentratedly to the fuse region 25a, and the current paths are blown in the same order in the fuse region 25 a. When all of the current paths P8 to P14 of the fuse region 25a are blown, the current paths are cut off, and the overcurrent no longer flows.

The above-described fusing process will be described with reference to fig. 8 and 9. As shown in a of fig. 8, an overcurrent flows through the current paths P1 and P2 of the fuse region 24a, and these current paths P1 and P2 have high temperatures. The hatched area indicates a portion having a high temperature due to heat generation. In addition, a diagonal double line is added to the blown current path.

When the current paths P1 and P2 blow, as shown in B of fig. 8, a current flows through the current paths P3 and P4 of the fuse region 24a, and these become high temperatures. Further, as shown in C of fig. 8, when the current paths P1 to P4 of the fuse region 24a are blown, a current flows through the current paths P5, P6, and P7, and these current paths P5 to P7 are at high temperatures. Further, the temperature of the current paths P8, P9, and P10 in the fuse region 25a rises.

As shown in a of fig. 9, when the current paths P1 to P7 of the fuse region 24a are blown, a current flows through the current paths P8, P9, P10, and P11 of the fuse region 25a, and these current paths P8 to P11 are at a high temperature. When the current paths P8 to P11 blow, the temperatures of the current paths P12, P13, and P14 increase as shown in B of fig. 9. Then, these current paths P12 to P14 fuse, and the current path from the battery pack device to the load is cut off, thereby protecting the battery pack device from an overcurrent.

As shown in fig. 8 and 9, in the first embodiment of the present invention, since a plurality of current paths having different resistance values are formed in the connection electrodes T1 and T17, a current can be concentrated to a current path having a low resistance value, and fusing can be performed reliably and at high speed. Compared with the conventional structure in which one narrowed portion is used as the fusing portion or the structure in which the current paths on both sides of the slit are used as the fusing portion, the width of the fusing portion can be prevented from being reduced, and the mechanical strength of the connection electrode can be prevented from being lowered.

In addition, since the plurality of

fuse regions

24a and 25a are provided and a large amount of current is caused to flow to the fuse region 24a first, the mechanical strength of the connection electrode can be maintained. If only one fuse region is provided, the length of the stripe-shaped current path must be made longer, which leads to a problem that the mechanical strength of the connection electrode is reduced. Further, by concentrating the current flowing to one of the two fuse regions, the current value can be increased and the fusing time can be shortened. Three or more fuse regions may be provided.

Next, a second embodiment of the present invention will be explained. The second embodiment of the present invention is applied to the connection electrode T1 or T17 of the battery device similar to the first embodiment described above. As shown in fig. 10, upper surface 111b and side surface 112b of connection electrode T17 contact at the bent position. A slit 115b is formed in the side surface 112b of the connection electrode T17, and the side surface 112b is divided into a base portion contacting the bent position, a connection portion having a narrow width, and a connection portion having a wide width and having an opening 114b to which the negative-electrode-side power cable 2 — is attached. That is, the side surface 112b has an inverted L-shape.

A repeating pattern of a plurality of, for example, 10 polygonal, for example, regular hexagonal openings is formed in a partial region of the coupling portion and the connecting portion connected to the coupling portion. A region in which regular hexagonal openings are repeatedly formed is referred to as a honeycomb pattern region 124 b. In the honeycomb pattern region 124b, a region between the openings serves as a current path having a predetermined width.

In the case of the negative connection electrode T17, since current is supplied through the negative power cable 2 attached to the opening 114b, the current input region 120b is formed on the connection portion side and the current output region 122b is formed on the base portion side. Therefore, the current is supplied from the current input region 120b to the battery pack device through the honeycomb pattern region 124b and the current output region 122 b. The honeycomb pattern region 124b has a function as a fuse region, and in the case where an overcurrent flows, a current path is blown, thereby protecting the battery pack device.

Fig. 11 shows an equivalent circuit of the honeycomb pattern region 124b between the current input region 120b and the current output region 122 b. The resistance value corresponding to the current path Pi located on the side of each regular hexagon of the honeycomb pattern region 124b is represented as Ri. To avoid complication, resistance values R111, R112, R113, … …, R121 corresponding to parts of the current paths P111, P112, P113, … …, P121 of the honeycomb pattern region 124b, respectively, are shown in fig. 11.

In the equivalent circuit, since the circuit length on the current input side and the circuit length on the current output side are substantially equal to each other, the resistance values (R111, R112, R113, and R114) on the input side have substantially equal values to each other, and the resistance values (R115 and … …) on the output side also have substantially equal values to each other. Further, since the sides of the regular hexagon have the same length and the same width, the resistance values of the current paths corresponding to the sides are also substantially equal to each other.

Therefore, the resistance value between the input and the output depends on the length of the current path. For example, in fig. 11, the combined resistance value is the smallest because the current path passing through the resistance values R111 and R115 is the shortest. The second smallest resistance value is a combined resistance value of the resistance value R112, the resistance values R117, R116, and R115. In this manner, in the second embodiment, a plurality of current paths having different resistance values are formed, as in the first embodiment. Then, the current is concentrated to the current path having a small resistance value, and the current path is blown.

The fusing process of the electrodes in the second embodiment will be described with reference to fig. 12. Fig. 12 shows an example of the positive-side connection electrode T1, in which the bent edge side of the connection electrode T1 serves as a current input region 120a, and the side of the opening 114a where the connection electrode power cable 2+ is attached serves as a current output region. In addition, a region which becomes a high temperature due to heat generation is indicated by hatching, and a double line is added to a current path for fusing.

When an overcurrent flows, the current is first concentrated in the current path having the smallest resistance value, and the current path indicated by hatching in fig. 12a generates heat, resulting in a high temperature. When the current path is blown, the current is concentrated on the current path having the second smallest resistance value, and the current path shown by oblique lines in fig. 12B generates heat and becomes high in temperature. Further, when the current path indicated by oblique lines in B of fig. 12 is blown, the current path indicated by oblique lines in C of fig. 12 generates heat and becomes a high temperature. By repeating such an operation, the honeycomb pattern region 124a is blown off sequentially or gradually, and the current path is cut off. By this sequential fusing or step-by-step fusing operation, a current can be concentrated and flow through a narrow current path, and thus the fusing operation can be performed at high speed.

The honeycomb pattern regions 124a and 124B are regions in which regular hexagonal openings are continuously formed, but patterns such as a triangular pattern region 125 (fig. 13 a) in which regular triangular openings are continuously formed, and a rhombic pattern region 126 (fig. 13B) in which rhombic openings are continuously formed may be formed. These polygonal patterns allow a high-speed fusing operation to be performed while maintaining mechanical strength.

The present invention is not limited to the above-described embodiments of the present invention, and various modifications and applications can be made without departing from the spirit of the present invention. For example, the conductive plate according to the present invention can be used for applications other than connection of batteries.

For example, the numerical values, structures, shapes, materials, manufacturing processes, and the like recited in the above embodiments and examples are merely examples, and numerical values, structures, shapes, materials, manufacturing processes, and the like different from them may be used as necessary.

Description of the reference numerals

1 … battery pack bracket, 2+ … positive side power cable, 2- … negative side power cable, 3 … control substrate, 11a, 11b … upper surface, 12a, 12b … side surface, 14a, 14b … opening, 18a, 18b, 19a, 19b … area, 24a, 24b, 25a, 25b … fuse area, P1-P14 … current path

Claims

1. A conductive plate having an energizing path between a current input region and a current output region, the energizing path being fused when an overcurrent flows,

the energizing path includes a plurality of current paths having different resistance values.

2. The conductive plate of claim 1,

the power-on path includes: a first current path group having a plurality of current paths having different resistance values; and a second current path group having a plurality of current paths different in resistance value,

a first combined resistance value of the first current path set is different from a second combined resistance value of the second current path set.

3. The conductive plate of claim 1 or 2,

the plurality of current paths included in the first current path group and the second current path group are sequentially fused when an overcurrent flows.

4. The conductive plate of claim 1 or 2,

the plurality of current paths have stripe-shaped current paths parallel to each other.

5. The conductive plate of claim 4,

the resistance value is set by the width or length of the striped current path.

6. The conductive plate of claim 1 or 2,

the conductive plate has a region in which a repeating pattern of a plurality of polygonal openings is formed, and the plurality of current paths are formed by regions between the openings.

7. The conductive plate of claim 6,

the conductive plate is formed with a bent energizing path, and the region is formed in the energizing path.

8. The conductive plate of any one of claims 1 to 7,

the plurality of current paths are formed on a surface different from a surface on which the plurality of welding regions are formed.

9. A battery device in which electrodes of a plurality of batteries are electrically and mechanically connected through a conductive plate,

the conductive plate has a conduction path between the current input region and the current output region, the conduction path including a plurality of current paths having different resistance values, and the conduction path is fused when an overcurrent flows.