JP2003257396A - Pack battery - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To quickly surely shut off current when battery temperature is abnormally raised with the number of heat sensitive protection elements less than the number of thin batteries, and simplify the assembly by jointly using the heat sensitive protection element to connect the battery, and moreover firmly connect the thin batteries. <P>SOLUTION: This pack battery has a plurality of thin batteries 3 arranged in a posture being stacked on a printed circuit board 4, and the heat sensitive protection element 6 for detecting the temperature of the thin batteries 6. In the pack battery, both ends of a heat sensitive lead plate 10 are connected to the end surface of the adjacently stacked thin batteries 3, and one lead plate 6B of the heat sensitive protection element 6 is connected to the middle of the heat sensitive lead plate 10. In the heat sensitive protection element 6, a temperature detecting part 6 is approached to the end of the thin batteries 3 and arranged between the adjacent thin batteries 3, and the other lead plate 6C connected to the temperature detecting part 6A is connected to the printed circuit board 4. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a battery pack formed by stacking a plurality of thin batteries, and more particularly to a battery pack incorporating a heat-sensitive protection element for detecting the temperature of the thin batteries.

[0002]

2. Description of the Related Art A pack battery in which a plurality of thin batteries are stacked and housed in a case can have a larger capacity with respect to the outer shape than a pack battery containing a plurality of cylindrical batteries. This is because they can be stacked without a gap and the volume efficiency can be improved. When cylindrical batteries are arranged in parallel and housed in a case, a gap like a valley is formed between the cylindrical batteries, but this gap cannot be formed in a thin battery. Taking advantage of this feature, pack batteries formed by stacking thin batteries are often used in applications requiring a particularly large capacity, such as video cameras.

As a pack battery having this structure, a type in which lithium ion secondary batteries, which are thin batteries, are stacked and housed in a case is often used. The battery pack of the lithium-ion secondary battery has a built-in heat-sensitive protection element that detects the temperature of the battery and shuts off the current in order to enhance safety.
When the temperature becomes higher than the set temperature,
A PTC or the like is used in which electric resistance rapidly increases and almost no current flows. Not only the lithium ion secondary battery but also all other secondary batteries can improve the safety by shutting off the current when the battery temperature rises to the set temperature by the thermal protection element.

When the battery temperature becomes higher than the set temperature, in order to cut off the current and improve the safety, the conventional pack battery having a plurality of thin batteries built therein has a heat-sensitive protection element for each thin battery. It is built in.

[0005]

The battery pack of this structure is a heat-sensitive protection element such as a PTC built in a thin battery, and can cut off the current when the battery temperature becomes higher than a set temperature. However, the battery pack having this structure has the same number of heat-sensitive protection elements as the thin batteries to be built in each thin battery, and thus has a drawback of high manufacturing cost. In order to eliminate this drawback,
In a battery pack in which a plurality of cylindrical batteries are arranged in parallel and housed in a case, a temperature sensor is arranged in the valley of the cylindrical battery to detect the battery temperature. The temperature sensor is located between the two cylindrical batteries and detects the temperature of the two batteries to shut off the current.

However, the battery pack having this structure is
It is difficult to detect two battery temperatures quickly with one temperature sensor. This is because the temperature sensor causes the temperature detection unit to be in close contact with the surface of the cylindrical battery and conducts the temperature of the battery to the temperature detection unit for detection. In particular, since the width of both side surfaces of a thin battery is extremely narrow, if a temperature sensor is provided here, the area where heat can be conducted becomes small, and the battery temperature cannot be quickly conducted to the temperature detecting portion. Therefore, there is a drawback that the temperature detection of the battery is delayed and the current cannot be interrupted promptly. In addition, since the cylindrical battery has a valley shape and a wasteful space can be provided, a temperature sensor can be disposed here. However, even if a thin battery is stacked, the wasteful space that can be formed at the boundary is extremely small and the wasteful space can be used. Therefore, the temperature sensor cannot be installed. If the temperature sensor is forcibly placed between the thin batteries, this will protrude and increase the outer size of the battery pack. This loses the feature of the battery pack in which thin batteries that can increase the charging capacity per volume are stacked.

The present invention was developed for the purpose of solving such drawbacks. It is an important object of the present invention to provide a battery pack that has a smaller number of heat-sensitive protection elements than a thin battery and can promptly and reliably cut off current when the battery temperature becomes abnormally high. Another important object of the present invention is to provide a battery pack in which a heat-sensitive protective element is also used for battery connection so that assembling can be simplified and a thin battery can be firmly connected.

[0008]

The battery pack of the present invention comprises:
The plurality of thin batteries 3 are arranged in a posture of being stacked on the printed circuit board 4, and the thermal protection element 6 for detecting the temperature of the thin batteries 3 is provided. In the battery pack, both ends of the heat-sensitive lead plate 10 are connected to the battery end faces of the thin batteries 3 that are adjacently stacked, and the heat-sensitive protection element 6 is provided between the heat-sensitive lead plates 10.
One of the lead plates 6B is connected. Thermal protection element 6
The temperature detecting portion 6A is arranged close to the end of the thin battery 3 and is arranged between the adjacent thin batteries 3, and the other lead plate 6C connected to the temperature detecting portion 6A is connected to the printed circuit board 4. Connected to.

The heat-sensitive lead plate 10 and the one lead plate 6B of the heat-sensitive protective element 6 may be made of different metal plates and welded to each other to be connected in a T-shape, or one metal plate may be connected to a T-shape.
The heat-sensitive lead plate 10 and one of the lead plates 6B of the heat-sensitive protection element 6 may be integrally formed by cutting into a letter shape.
Both ends of the T-shaped heat-sensitive lead plate 10 can be connected to the thin battery 3 by welding to the battery end surface.

Further, in the battery pack of the present invention, four thin batteries 3 are arranged in a stacked state, one thermal protection element 6 is arranged at each end of the thin battery 3, and one thermal protection element 6 is used. The temperatures of the two thin batteries 3 can be detected.

Further, in the battery pack of the present invention, a holder 5 formed of an insulating material can be sandwiched and arranged between the thin battery 3 and the printed circuit board 4. This holder 5 is provided with a projecting portion 5C projecting on the battery end surface of the thin battery 3 on the periphery thereof, and the connecting lead plate 11 is attached to this projecting portion 5C.
And a pair of ribs 5D that guide the
The connection lead plate 11 can be arranged between the pair of ribs 5D.

Further, in the battery pack of the present invention, the thin connecting plate 11 for connecting the battery end face of the thin battery 3 to the printed circuit board 4 and the connecting lead plate 11 for connecting the thermal protection element 6 to the printed circuit board 4 are thin. It can be arranged at both ends of the battery end surface of the battery 3. This battery pack can reliably prevent these connecting lead plates 11 from coming into contact with each other to cause a short circuit.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. However, the examples described below exemplify the battery pack for embodying the technical idea of the present invention, and the present invention does not specify the battery pack as follows.

Further, in this specification, in order to facilitate understanding of the claims, the numbers corresponding to the members shown in the embodiments are referred to as "claims column" and "to solve the problem." It is added to the members shown in "Means column".
However, the members shown in the claims are not limited to the members of the embodiment.

The battery pack shown in FIGS. 1 to 3 includes a case 1, a printed circuit board 4 disposed on the bottom of the case 1, and a plurality of thin batteries 3 stacked on the printed circuit board 4. A holder 5 sandwiched between the thin battery 3 and the printed circuit board 4 is provided. The battery pack shown is
The four thin batteries 3 are stacked and housed in the case 1.
However, the present invention does not specify the number of laminated thin batteries to be four. Two or more thin batteries can be stacked and stored in the case.

FIGS. 4 to 7 show the battery core 2 housed in the case 1. Battery core 2 is thin battery 3
The printed circuit board 4 and the holder 5 are integrally connected. The battery core 2 is put in the case 1, and the case 1 is closed and assembled. The case 1 is made of plastic, and is a box case 1A in which the battery core 2 can be placed.
And a lid case 1B for closing the opening of the box case 1A.
With. The box case 1A and the lid case 1B are connected by ultrasonic welding. However, it is also possible to connect them by adhering or fitting, or by screwing. The lid case 1B has an opening of an electrode window 8 for exposing the output terminal 7 fixed to the printed board 4 of the battery core 2 to the outside.

A plurality of thin batteries 3 are connected to a printed circuit board 4. FIG. 8 shows a circuit diagram of the battery pack. In the battery pack of this circuit diagram, two thin type batteries 3 are connected in parallel, and two thin type batteries 3 connected in parallel are connected in series. That is, four thin batteries 3 are connected in series and in parallel. In the battery pack, all of the plurality of thin batteries 3 can be connected in series or connected in parallel. The thin battery 3 is a lithium ion secondary battery. However, thin-type batteries include nickel-hydrogen batteries and nickel-hydrogen batteries.
It can be any secondary battery such as a cadmium battery. The output voltage of the secondary battery varies depending on the type of battery, but the optimum output voltage required for the battery pack can be adjusted by connecting in series or in parallel according to the output voltage of each thin battery. You can

The plurality of thin batteries 3 are stacked in such a manner that the battery end faces at both ends are located on the same plane. A buffer sheet 9 is sandwiched between the thin batteries 3. The cushioning sheet 9 has a rectangular shape along the periphery of the thin battery 3 and has a through hole in the center. In this way, since the buffer sheet 9 has a frame-like shape with a through hole provided in the center, a space is formed in the center between the thin batteries 3 by the thickness of the buffer sheet 9. The thin battery 3 may swell at its center due to overcharging or the like, but even if the thin battery 3 swells, the presence of the buffer sheet 9 absorbs the swelling and does not deform the outer shape of the battery core 2.

One end faces of the thin batteries 3 stacked next to each other are connected to each other via a heat sensitive lead plate 10.
In the battery pack shown in the figure, the thin type battery 3 is connected in parallel by the heat-sensitive lead plate 10. The heat-sensitive lead plate 10 is a metal plate, and is welded by a method such as spot welding or laser welding to electrically connect the thin batteries 3 stacked next to each other. Further, the heat-sensitive lead plate 10 is used together with a heat conductor that conducts the temperature of the thin battery 3. Therefore, the heat-sensitive lead plate 10 has one lead plate 6B of the heat-sensitive protection element 6 connected in the middle thereof. The heat-sensitive protection element 6 is connected to the battery end surface of the thin battery 3 via the heat-sensitive lead plate 10 so that the temperature detecting portion 6A approaches the end of the thin battery 3, and
The temperature detection unit 6A is arranged between the thin batteries 3 adjacent to each other.

In the battery pack shown in the figure, the temperature detecting portion 6A is arranged in the center of the adjacent thin battery 3. The heat-sensitive protection element 6 has a feature that it can quickly detect the temperature of the two thin batteries 3 in a well-balanced manner. However, the thermal protection element 6 is
Since the temperature detecting unit 6A is connected to the two thin type batteries 3 via the heat sensitive lead plate 10, the heat generation of the two thin type batteries 3 is conducted to the temperature detecting unit 6A via the heat sensitive lead plate 10. For this reason, the temperature detection unit 6A does not necessarily have to be arranged at the center of the two thin batteries 3, and the heat-sensitive protection element 6 can quickly generate heat from the two thin batteries 3 even if they are displaced in the direction of one of the thin batteries 3. To detect. Therefore, the temperature detection unit 6A does not necessarily have to be accurately arranged in the center of the adjacent thin batteries 3, and may be arranged deviated from the center.

The battery pack shown in the figure includes four thin batteries 3. One thermal protection element 6 is two thin batteries 3
Detects the temperature of. Therefore, the battery pack containing the four thin batteries 3 includes the two thermal protection elements 6. That is, the pack battery including the even number (n) of thin batteries 3 includes n / 2 heat-sensitive protection elements 6, which is half of the thin batteries 3. A battery pack containing an odd number (n) of thin batteries 3 includes (n + 1) / 2 thermal protection elements 6. In a battery pack containing an odd number of thin batteries 3, one of the heat-sensitive protection elements 6 detects the temperature of one thin battery 3.

In the battery pack shown in the figure, one heat-sensitive protection element 6 is arranged on one battery end surface of the thin battery 3, and the remaining heat-sensitive protection element 6 is arranged on the other battery end surface. That is,
One heat-sensitive protection element 6 is arranged at each end of the thin type battery 3, and the temperature of the two thin type batteries 3 is detected by the one heat-sensitive protection element 6.

FIG. 9 is a plan view of the heat-sensitive protection element 6.
In the heat-sensitive protection element 6 of this figure, lead plates 6B, which are metal plates, project from both ends of the temperature detecting portion 6A. A heat-sensitive lead plate 10 manufactured by cutting a metal plate is connected to one of the lead plates 6B by a method such as welding. Heat sensitive lead plate 10
After being connected to the lead plate 6B by a method such as welding, both ends thereof are welded and connected to the battery end surface. The heat-sensitive protective element 6 shown in the figure is a heat-sensitive lead plate 1 manufactured separately from the lead plate 6B.
0 is connected to the lead plate 6B. However, in the heat-sensitive protection element 6, as shown in FIG. 10, the lead plate 6B of the heat-sensitive protection element 6 and the heat-sensitive lead plate 10 can be integrated. The heat-sensitive protection element 6 shown in this figure is provided with one lead plate 6
B has a T shape, and the heat-sensitive lead plate 10 has an integral structure. This heat-sensitive protection element 6 has a T-shaped both ends, in other words, a heat-sensitive lead plate 1 integrally formed with a lead plate 6B.
Both ends of 0 are connected to the battery end surface of the thin battery 3 by welding or the like. This structure has a feature that heat can be most efficiently conducted from the heat-sensitive lead plate 10 to the lead plate 6B of the heat-sensitive protection element 6.

The other lead plate 6C connected to the temperature detecting portion 6A of the heat-sensitive protection element 6 is connected to the printed board 4. The battery pack shown in the figure is the lead plate 6 of the heat-sensitive protection element 6.
The connection lead plate 11 is welded and connected so as to be orthogonal to C, and the lead plate 6C of the heat-sensitive protection element 6 is connected to the printed board 4 via the connection lead plate 11A. The first connecting lead plate 11A on the end face of the battery located on the side opposite to the output terminal 7 and connecting the lead plate 6C of the heat-sensitive protection element 6 to the printed circuit board 4 is linear as shown in FIG. It is a metal plate cut into pieces. The second connecting lead plate 11B, which connects the lead plate 6C of the heat-sensitive protection element 6 to the printed circuit board 4 on the battery end surface on the output terminal 7 side, is formed by cutting a metal plate into an L shape. As shown in FIGS. 3 to 5, the connection lead plate 11 is bent along the corner of the thin battery 3 and is connected to the printed board 4 at a position away from the output terminal 7. In the battery pack having this structure, the second connection lead plate 11B and the output terminal 7 can be disposed separately from each other, so that in the event of an emergency, it is possible to effectively prevent short-circuiting between the two.

The battery core 2 is, as shown in FIGS. 2 and 6,
Two rows of connection lead plates 11 connected to the printed circuit board 4 are provided on one end face of the battery. One of the first connection lead boards A connects the leads of the heat-sensitive protection element 6 to the printed circuit board 4, and the other third connection lead board 11C.
In the figure, the battery end surfaces of the upper two thin batteries 3 are connected to the printed circuit board 4. In this battery core 2, the first connecting lead plate 11A is provided on the right side of the battery end face in the drawing,
The connecting lead plate 11C is arranged on the left side of the battery end face, and the first connecting lead plate 11A and the third connecting lead plate 11C are arranged at both ends of the battery end face of the thin battery 3. This structure has a feature that it is possible to reliably prevent a short circuit between the first connecting lead plate 11A and the third connecting lead plate 11C. In the figure, the third connecting lead plate 11C is
It is insulated from the battery end surface of the stepped thin battery 3. This is because the insulating sheet 12 is arranged on the battery end surface of the lower two-tier thin battery 3.

The other battery end surface of the battery core 2 shown in FIGS. 3 and 7 connects the thermal protection element 6 and the battery end surface of the thin battery 3 to the printed circuit board 4 with the second connecting lead plate 11B in one row. ing. The second connection lead plate 11B has its upper end connected to the lead plate 6C of the heat-sensitive protection element 6 at a right angle by a method such as welding, and the middle thereof is welded to the battery end surface of the lower two-stage thin battery 3 by a method such as welding. Are connected with. Further, the second connection lead plate 11B is bent along the corner of the lowermost thin battery 3 and has its tip connected to the printed circuit board 4.

As shown in the bottom view of FIG. 4, the connecting lead plate 11 has its tip bent along the lower surface of the printed circuit board 4 and the bent end thereof is soldered or the like.
Connected to. The printed circuit board 4 has an electronic component 13 that realizes a protection circuit for the thin battery 3 fixed thereto by a method such as soldering, and further has an output terminal 7 fixed to a holder 5.
Is also soldered and connected.

The connection lead plate 11 connected to the thin battery 3 and the heat-sensitive protection element 6 is connected to the printed circuit board 4, and the thin battery 3 and the printed circuit board 4 are connected to each other. Further, the holder 5 is fixed by being sandwiched between the thin battery 3 and the printed board 4, and the thin battery 3 and the printed board 4 are positioned and arranged at fixed positions via the holder 5.

The holder 5 is manufactured by molding an insulating material such as plastic. The holder 5 is integrally formed with a side wall 5A into which the printed circuit board 4 is fitted on the lower surface. The side wall 5A is provided on the peripheral edge so as to project to the lower surface. The side wall 5A is provided at a portion other than the portion connecting the connection lead plate 11 to the printed board 4. The side wall 5A has such a height that the printed circuit board 4 can be housed inside, that is, the printed circuit board 4
The electronic component 13 fixed to is molded to a height that does not protrude from the side wall 5A. Further, the holder 5 is a thin battery 3
A battery fixing rib 5B for projecting to the side and for positioning the thin battery 3 is integrally formed and provided. Two battery fixing ribs 5B are provided on each side of the thin battery 3.

Further, as shown in FIG. 2, the holder 5 projects toward the thin battery 3 side on the battery end face located on the side opposite to the output terminal 7 to surely insulate the connection lead plate 11 from the battery end face. 5C is integrally formed and provided. The protrusion 5C is provided with a pair of ribs 5D integrally molded to guide the connection lead plate 11 and hold it at a fixed position. The connecting lead plate 11 is disposed between the pair of ribs 5D, and the projecting portion 5C insulates the connecting lead plate 11 from the battery end surface. The battery pack having this structure insulates the connecting lead plate 11 and the battery end face from each other by the protrusion 5C provided on the holder 5, so that the connecting lead plate 11 can surely be prevented from coming into contact with the battery end face to cause a short circuit. There is. Further, the holder 5 has an output terminal 7
As shown in FIG. 3, the battery end surface located on the side is integrally formed with a protruding portion 5E that projects toward the thin battery 3 side and positions the thin battery 3.

The holder 5 is disposed between the lowermost thin battery 3 and the printed circuit board 4 in the figure, and the printed circuit board 4 is fixed to the lower surface thereof. As shown in FIG. 4, the holder 5 includes a locking hook 5 protruding inward from the side wall 5A.
F is provided, and the printed circuit board 4 is locked by the locking hook 5F to fix the printed circuit board 4. The holder 5 shown in the figure is provided with three locking hooks 5F, which are arranged on the side surface of the printed circuit board 4 so as to approach the corners.
The printed circuit board 4 is held at three places. Further, the holder 5 is provided with a positioning protrusion 5G protruding from the lower surface in order to connect the printed circuit board 4 to an accurate position. The printed board 4 has a connection hole 4A into which the positioning protrusion 5G is inserted, which is opened at a position facing the positioning protrusion 5G. The positioning protrusion 5G and the connecting hole 4A are provided close to three corners of the four corners of the printed circuit board 4. The printed circuit board 4 is positioned at a fixed position of the holder 5 while guiding the positioning protrusions 5G into the connecting holes 4A, and is locked by the locking hooks 5F to be connected to a predetermined position. The printed circuit board 4 is fixed to the holder 5, and the connection lead plate 11 connected to the thin battery 3 is connected to the printed circuit board 4, so that the thin battery 3, the holder 5, and the printed circuit board 4 are connected.
And are integrally connected.

[0032]

The battery pack of the present invention has a smaller number of heat-sensitive protective elements than thin batteries, and is characterized in that the current can be promptly and reliably interrupted when the battery temperature becomes abnormally high. This is because the battery pack of the present invention connects both ends of a heat-sensitive lead plate to the battery end faces of thin batteries that are stacked adjacent to each other, and connects one lead plate of the heat-sensitive protection element to the middle of the heat-sensitive lead plate. In addition, the temperature detecting portion of the heat-sensitive protective element is disposed close to the end of the thin battery and between the adjacent thin batteries. In the battery pack with this structure, the temperature detection part of the heat-sensitive protection element is connected to two adjacent thin batteries via the heat-sensitive lead plates, so the heat generation of the two thin batteries is detected via the heat-sensitive lead plates. The heat generated by the two thin batteries can be quickly detected by conducting the heat conduction to the battery. Furthermore, since the temperature-sensitive protection element has the temperature detection unit located close to the end of the thin type battery and arranged between the adjacent thin type batteries, the heat generation of the two thin type batteries can be detected more effectively. Therefore, the battery pack of the present invention can detect the abnormality of the battery temperature promptly and cut off the current surely while the number of the heat-sensitive protective elements is smaller than that of the thin battery. Further, since the battery pack of the present invention can be used together with the heat-sensitive protective element for battery connection, the battery pack can be assembled easily and thin batteries can be firmly connected.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of a battery pack according to an embodiment of the present invention.

2 is a sectional view of the battery pack shown in FIG. 1 taken along the line AA.

3 is a sectional view of the battery pack shown in FIG. 1 taken along the line BB.

4 is a bottom view of a battery core incorporated in the battery pack shown in FIG.

5 is a front view of a battery core incorporated in the battery pack shown in FIG.

6 is a right side view of the battery core shown in FIG.

7 is a left side view of the battery core shown in FIG.

FIG. 8 is a circuit diagram of the battery pack shown in FIG.

FIG. 9 is a plan view showing a heat-sensitive lead plate and a heat-sensitive protection element.

FIG. 10 is a plan view showing another example of the heat-sensitive lead plate and the heat-sensitive protection element.

[Explanation of symbols]

1 ... Case 1A ... Box case 1
B ... Lid case 2 ... Battery core 3 ... Thin battery 4 ... Printed circuit board 4A ... Connection hole 5 ... Holder 5A ... Side wall 5
B ... Battery fixing rib 5C ... Projection part 5D ... Rib 5E ... Projection part 5F ... Locking hook 5G ... Positioning convex part 6 ... Thermal protection element 6A ... Temperature detecting part 6
B ... Lead plate 6C ... Lead plate 7 ... Output terminal 8 ... Electrode window 9 ... Buffer sheet 10 ... Thermal lead plate 11 ... Connection lead plate 11A ... First connection lead plate 11B ... Second connection lead plate 11C ... Third Connection lead plate 12 ... Insulation sheet 13 ... Electronic component

Claims (5)

[Claims] 1. A battery pack in which a plurality of thin batteries (3) are arranged in a posture in which they are stacked on a printed circuit board (4), and which includes a heat-sensitive protection element (6) for detecting the temperature of the thin batteries (3). In addition, both ends of the heat-sensitive lead plate (10) are connected to the battery end faces of the thin batteries (3) that are stacked next to each other.
Connect the one lead plate (6B) of the heat-sensitive protection element (6) to the middle of (10), and connect the temperature detection part (6A) of the heat-sensitive protection element (6) to a thin battery.
The other lead plate (6C), which is disposed between the thin batteries (3) adjacent to and close to the end of (3) and is connected to the temperature detection unit (6A), is connected to the printed circuit board (4C). ) Connected to the battery pack. 2. The heat-sensitive lead plate (10) and one lead plate (6B) of the heat-sensitive protection element (6) are made of different metal plates and welded to each other to be connected in a T-shape, or Heat-sensitive lead plate (10) and heat-sensitive protection element by cutting one metal plate into T shape
One lead plate (6B) of (6) is integrated with T
The battery pack according to claim 1, wherein both ends of the character shape are welded and connected to the battery end surface of the thin battery (3). 3. The four thin batteries (3) are arranged in a stacked state, one thermal protection element (6) is arranged at each end of the thin batteries (3), and one thermal protection element (6) is provided. The battery pack according to claim 1, wherein the temperature of the two thin batteries (3) is detected by (1). 4. A holder (5) formed of an insulating material is sandwiched between a thin battery (3) and a printed circuit board (4), and the holder (5) is provided at the periphery of the holder (5). The thin battery (3) has a protruding part (5C) protruding from the end face of the battery. This protruding part (5C)
A pair of ribs (5D) for guiding the connection lead plate (11) are integrally formed and provided, and the connection lead plate (11) is arranged between the pair of ribs (5D). The battery pack described in 1. 5. The thin battery (3) has a battery end face on a printed circuit board.
Connect the connecting lead plate (11) connected to (4) and the connecting lead plate (11) connecting the heat-sensitive protective element (6) to the printed circuit board (4) on both ends of the battery end face of the thin battery (3). Arranged claim 1.
The battery pack described in.