JP2005078858A - Battery pack - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce a processing cost and mass-produce with a low cost by simply and efficiently assembling owing to an arrangement of a temperature sensor at a position capable of surely detecting a battery temperature. <P>SOLUTION: A battery pack has a battery 2; a substrate 3 connected to the battery 2; a substrate holder 4 disposed between the substrate 3 and the battery 2 to dispose the substrate 3 at a fixed position against the battery 2; a temperature sensor 5 disposed close to the battery 2 to detect the battery temperature; and a thermal coupling resin 6 filled between the sensor 5 and a battery surface to thermally couple the sensor 5 to the battery 2. A substrate holder 4 disposed between the substrate 3 and the battery 2 has a notch 10 opened to both of the substrate 3 and the battery 2 and fixes the sensor 5 to the substrate 3 so as to be positioned at the notch 10. Moreover, the resin 6 is filled into the notch 10 with the sensor 5 disposed thereat and the sensor 5 fixed to the substrate 3 is thermally coupled to the battery surface. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a battery pack incorporating a temperature sensor.

A battery pack with a built-in temperature sensor can detect battery temperature and control charging and discharging of the battery. For example, when the battery temperature becomes abnormally high, charging and discharging of the battery can be stopped to prevent a decrease in performance due to the high temperature of the battery and can be used safely. In order to realize this, a battery pack incorporating a temperature sensor has been developed. (See Patent Document 1)
Japanese Utility Model Publication No. 7-29741

  The battery pack described in this publication is provided with a housing portion in which a temperature sensor is disposed in a case. The storage part opens on the side facing the battery. A temperature sensor is disposed in the housing portion and further filled with a silicon resin as a heat-bonding resin, thereby reducing the thermal resistance between the battery and the temperature sensor.

  In the battery pack having this structure, the relative position between the temperature sensor and the battery is likely to shift. This is because the dimensional error of the battery and the shift of the battery storage position cause the relative position between the battery and the temperature sensor to shift. If the temperature sensor is not disposed at a specific position with respect to the battery, the temperature sensor cannot accurately detect the battery temperature. Further, the battery pack having this structure has a drawback that it is difficult to assemble efficiently because the temperature sensor is fixed to the case. This is because it is necessary to fill a specific position with silicon resin in a state where the temperature sensor and the battery are separately housed in a case and arranged at a predetermined position. As described above, the structure in which the temperature sensor is arranged in the case and filled with the silicon resin in a separate process from the battery cannot be efficiently assembled, but also causes the relative position between the battery and the temperature sensor to be shifted.

  By the way, the battery pack can be efficiently and inexpensively manufactured as a structure in which the battery can be put in a case and assembled in the state of a core pack. The core pack of the battery is obtained by connecting a temperature sensor, a substrate, and the like as an integrated structure. The monolithic core pack can be simply and efficiently assembled in a case. The battery core pack does not need to put multiple parts separately in a specific position of the case like a battery and a temperature sensor, and it is also necessary to fill a specific position with silicon resin in the case. Because there is no, it can be assembled efficiently. However, in a conventional battery pack, a space for filling a silicone resin that thermally couples the temperature sensor to the battery cannot be secured in a state where the battery is a core pack. For this reason, the conventional battery pack has a drawback that the temperature sensor cannot be accurately disposed at a specific position with respect to the battery in a state where the battery is a core pack, and the battery temperature cannot be accurately detected.

  The present invention was developed for the purpose of solving the above problems, and an important object of the present invention is that a temperature sensor can be arranged at a position where the battery temperature can be accurately detected, and it is simple and efficient. It is an object of the present invention to provide a battery pack that can be well assembled, further reduces the unit cost, reduces processing costs, can be mass-produced at low cost, and has a space-saving structure and can accurately place a temperature sensor.

  The battery pack according to the present invention includes a battery 2, a substrate 3 connected to the battery 2, and a substrate 3 disposed between the substrate 3 and the battery 2 at a fixed position with respect to the battery 2. A substrate holder 4, a temperature sensor 5 for detecting the battery temperature, and a thermal coupling resin 6 that is filled between the temperature sensor 5 and the battery surface and thermally couples the temperature sensor 5 to the battery 2. The substrate holder 4 disposed between the substrate 3 and the battery 2 includes a notch 10 that is open to both the substrate 3 and the battery 2, and the substrate 3 has a temperature so as to be positioned at the notch 10. The sensor 5 is fixed. Further, the notch 10 in which the temperature sensor 5 is disposed is filled with the thermal bonding resin 6 so that the temperature sensor 5 fixed to the substrate 3 is thermally coupled to the battery surface.

  In the battery pack of the present invention, the substrate 3, the battery 2 and the substrate holder 4 are accommodated in the case 1, and a shielding cover 15 is provided between the battery facing surface of the substrate 3 and the inner surface of the case. It is possible to prevent the thermal bonding resin 6 from leaking to the surface of the substrate 3 by making contact with the inner surface of the case. The substrate holder 4 is made of plastic, and the ribs 14 that are in contact with the battery 2 and the substrate 3 are integrally formed, and the notch 10 can be provided between the pair of ribs 14. The battery 2 is a thin battery, and a substrate 3 and a substrate holder 4 can be disposed on the side surface of the battery 2.

  The battery pack of the present invention has a feature that a temperature sensor can be arranged at a position where the battery temperature can be accurately detected. This is because the battery pack according to the present invention is provided with a notch in the substrate holder disposed between the battery and the substrate, and the temperature sensor is disposed here. In the battery pack of the present invention, a substrate holder is disposed between the substrate, the substrate is disposed at a fixed position with respect to the battery by the substrate holder, and a temperature sensor is provided at a notch provided in the substrate holder. Is arranged. Since the substrate holder is disposed close to the battery, the temperature sensor disposed in the notch provided in the substrate holder is close to the battery and is disposed at an accurate position. The substrate holder connected to the battery is not displaced relative to the battery. For this reason, the temperature sensor disposed in the notch portion of the substrate holder is disposed at an accurate position with respect to the battery without being displaced relative to the battery due to a dimensional error of the battery. Therefore, the battery pack of the present invention can accurately detect the battery temperature by arranging the temperature sensor at an accurate position with respect to the battery. Furthermore, the battery pack according to the present invention has a feature that the temperature sensor can be arranged at an accurate position with a space-saving structure because the temperature sensor is arranged in the notch provided in the substrate holder.

  Furthermore, since the battery pack of the present invention can be assembled in a case in a state where the battery, the substrate, and the substrate holder are connected to form a core pack, there is a feature that the battery can be assembled easily and efficiently. Furthermore, the battery pack according to the present invention uses a substrate holder that holds the substrate in a fixed position together with a holder that places the temperature sensor in a fixed position. There is also a feature that enables mass production.

  Embodiments of the present invention will be described below with reference to the drawings. However, the example shown below illustrates 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, numbers corresponding to the members shown in the embodiments are shown in “Claims” and “Means for Solving the Problems”. It is added to the members. However, the members shown in the claims are not limited to the members in the embodiments.

  The battery pack shown in FIGS. 1 to 4 is disposed between the battery 2, the substrate 3 connected to the battery 2, and the substrate 3 and the battery 2. A substrate holder 4 disposed at a fixed position, a temperature sensor 5 for detecting a battery temperature, a thermal bonding resin 6 that is filled between the temperature sensor 5 and the battery surface and thermally couples the temperature sensor 5 to the battery 2, And a case 1 for storing them.

  Case 1 is a plastic molded product, and upper case 1A is connected to lower case 1B. The lower case 1B and the upper case 1A are connected by ultrasonic welding, or are bonded and fitted together. In the case 1 shown in the figure, the lower case 1B is formed into a box shape having an upper opening, and the upper case 1A is connected so as to close the opening. In the illustrated battery pack, the thin battery is accommodated in the case 1, and therefore the lower case 1B is formed into a box shape that can accommodate the thin battery, that is, a box shape whose inner shape is larger than the outer shape of the thin battery. The lower case 1 </ b> B accommodates a battery core pack 7 in which a substrate 3, a substrate holder 4, and a temperature sensor 5 are connected to the battery 2. Accordingly, the lower case 1B has an inner shape that is larger than the outer shape of the battery core pack 7.

  Further, the lower case 1B has an electrode window 9 for exposing the output terminal 8 fixed to the substrate 3 to the outside. The battery pack of FIG. 1 is provided with a notch 10 at the center of the substrate holder 4, an electrode window 9 is provided at the end of the substrate holder 4, and the notch 10 and the electrode window 9 are separated from each other. This structure can prevent the thermal coupling resin 6 such as silicon resin filled in the notch 10 from leaking to the surface of the output terminal 8 provided so as to be exposed to the electrode window 9.

  In the illustrated battery pack, the battery 2 is a thin lithium-ion battery, and one battery 2 is housed in the case 1. The battery 2 housed in the case 1 is not necessarily a thin battery, and may be a cylindrical battery or a square battery. Further, two or more batteries can be stored in the case. The battery is not necessarily a lithium ion battery, and can be any rechargeable battery such as a nickel metal hydride battery or a nickel cadmium battery.

  The substrate 3 fixes the output terminal 8 to the front side. The output terminal 8 is fixed at a position where it is exposed to the outside from the electrode window 9 provided in the case 1. Further, the substrate 3 is mounted with an electronic component 16 of a protection circuit for the battery 2. FIG. 5 shows a circuit diagram of a battery pack in which the protection circuit is mounted. In the battery pack of this circuit diagram, a temperature sensor 5 for detecting battery temperature is connected to a protection circuit 11. When the battery temperature becomes abnormally high, the protection circuit 11 stops charging / discharging of the battery 2 with a signal from the temperature sensor 5 or outputs a temperature signal to an electronic device in which the battery pack is mounted. The battery pack that outputs a temperature signal includes a signal terminal 12.

  In the illustrated battery pack, a substrate 3 and a substrate holder 4 are disposed so as to face the side surface of the thin battery 2. The substrate 3 is an elongated quadrangle, and has a length from one end where the convex electrode of the battery 2 is provided to the bottom. Further, in the battery pack shown in FIGS. 2 and 3, the width of the substrate 3 is substantially equal to the thickness of the thin battery 2. In the battery pack of FIG. 6, the width of the substrate 3 is narrower than that of the thin battery 2.

  The substrate holder 4 is disposed between the substrate 3 and the battery 2, and the substrate 3 is disposed at a fixed position of the battery 2. The substrate holder 4 is a plastic molded product. The substrate holder 4 has a shape in which the first surface 4 a comes into contact with the surface of the battery 2, and a second surface 4 b located on the opposite side of the first surface 4 a comes in contact with the substrate 3. The substrate holder 4 shown in the drawing has a first surface 4a as a plate portion 13 along the surface of the battery 2, and a rib 14 is integrally provided on the plate portion 13 of the first surface 4a so that the tip surface of the rib 14 is provided. Is the first surface 4a. As shown in the rear view of FIG. 7 and the perspective view of FIG. 8, the substrate holder 4 is provided with vertical ribs 14A along both sides of the plate portion 13, and a pair of horizontal ribs at both ends so as to connect the vertical ribs 14A. Ribs 14B are provided, and the substrate 3 is supported by the vertical ribs 14A and the horizontal ribs 14B.

  The substrate holder 4 disposed between the substrate 3 and the battery 2 is provided with a notch 10 that opens to both the substrate 3 and the battery 2. The notch 10 exposes a part of the battery facing surface of the substrate 3 to the surface of the battery 2, and the temperature sensor 5 is disposed here. The substrate holder 4 in the figure has a notch 10 between a pair of intermediate ribs 14C provided in the middle of the vertical ribs 14A. Further, as shown in FIGS. 7 and 8, the substrate holder 4 is provided with a notch 10 that opens at one side edge. In the substrate holder 4, the ends of the pair of intermediate ribs 14 </ b> C are connected by a connecting rib 14 </ b> D, and a region surrounded by the connecting rib 14 </ b> D and the pair of intermediate ribs 14 </ b> C is a notch 10. The notch 10 has a shape surrounding the three sides by a pair of intermediate ribs 14 </ b> C and a connecting rib 14 </ b> D, and one opening is closed by the case 1. The pair of intermediate ribs 14 </ b> C and the connecting ribs 14 </ b> D around the notch 10 make the front end surface a second surface 4 b and contact the surface of the substrate 3. Therefore, in a state where the substrate holder 4 is connected to the substrate 3 and the battery 2, the notch 10 is a region surrounded by the connection rib 14 </ b> D, the pair of intermediate ribs 14 </ b> C, and the substrate 3 as shown in the cross-sectional view of FIG. 3. It becomes. The temperature sensor 5 is fixed to the battery facing surface of the substrate 3 so as to be located inside the notch 10. In a state where the temperature sensor 5 is disposed in the notch 10 while being fixed to the battery facing surface of the substrate 3, the notch 10 is filled with a thermal bonding resin 6 such as a silicon resin. The thermal bonding resin 6 is filled from the upper opening in FIG.

  Further, the substrate holder 4 of FIG. 6 includes a shielding cover 15 that prevents the thermal bonding resin 6 filled in the notch 10 from leaking to the output terminal 8 side of the surface of the substrate 3. The shielding cover 15 is disposed between the battery facing surface of the substrate 3 and the inner surface of the case 1. The shielding cover 15 has one side edge in contact with the battery facing surface of the substrate 3 so that there is no gap. The other side edge of the shielding cover 15 is in contact with the inner surface of the case 1, more precisely, the inner surface of the side wall of the case 1. Since the battery pack having the shielding cover 15 can prevent the thermal bonding resin 6 filling the notch 10 from leaking to the surface of the substrate 3, the notch 10 is provided on the battery facing surface of the substrate 3 as shown in FIG. 6. The output terminal 8 is provided on the opposite surface where the notch 10 is provided. In other words, the output terminal 8 is provided at a position approaching the notch 10, and the thermal coupling resin 6 is provided on the surface of the output terminal 8. Can be prevented from leaking.

The battery pack having the above structure is manufactured as follows.
(1) The electronic component 16 of the protection circuit 11 and the temperature sensor 5 are fixed to the substrate 3 to which the output terminal 8 is fixed. The electronic component 16 is fixed to the battery facing surface and is disposed between the ribs 14 of the substrate holder 4.
(2) The substrate holder 4 is disposed between the battery 2 and the substrate 3, and the substrate 3 and the battery 2 are connected by the lead wire 17. The substrate holder 4 is fixed by being sandwiched between the substrate 3 and the battery 2 and connects the substrate 3 and the battery 2 in a fixed position. Since the temperature sensor 5 is fixed to the substrate 3 so as to be positioned in the notch 10 of the substrate holder 4, the temperature sensor 5 is disposed in the notch 10 of the substrate holder 4 when the substrate 3 is connected. In this state, the core pack 7 of the battery 2 in which the substrate 3 and the substrate holder 4 are integrally connected to the battery 2 is manufactured.
(3) The core pack 7 of the battery 2 is put in the lower case 1B, and the notch 10 of the substrate holder 4 is filled with the thermal bonding resin 6 such as silicon resin. The thermal bonding resin 6 thermally couples the temperature sensor 5 fixed to the substrate 3 to the battery 2.
(4) The upper case 1A is connected to the lower case 1B to complete the battery pack.

  In the above assembly method, the core pack 7 is put in the lower case 1B, and the heat coupling resin 6 is filled in the notch portion 10, but in the state of the core pack 7 connecting the substrate 3 and the substrate holder 4 to the battery 2, The notch 10 can be filled with the thermal bonding resin 6. As shown in FIG. 6, the substrate holder 4 is formed so that the cutout portion 10 is deepened so that the entire heat treatment resin 6 is not filled in the cutout portion 10. This is to prevent the thermal bonding resin 6 from leaking from the notch 10.

It is sectional drawing of the battery pack concerning one Example of this invention. FIG. 2 is a cross-sectional view of the battery pack shown in FIG. 1 taken along the line AA. FIG. 3 is an enlarged cross-sectional view of a main part of the battery pack shown in FIG. 2. It is a BB sectional view of the battery pack shown in FIG. 1 is a circuit diagram of a battery pack according to an embodiment of the present invention. It is a principal part expanded sectional view of the battery pack concerning the other Example of this invention. It is a rear view of the board | substrate holder of the battery pack shown in FIG. It is a perspective view of the substrate holder shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Case 1A ... Upper case 1B ... Lower case 2 ... Battery 3 ... Board | substrate 4 ... Board | substrate holder 4a ... 1st surface 4b ... 2nd surface 5 ... Temperature sensor 6 ... Thermal coupling resin 7 ... Core pack 8 ... Output terminal DESCRIPTION OF SYMBOLS 9 ... Electrode window 10 ... Notch part 11 ... Protection circuit 12 ... Signal terminal 13 ... Plate part 14 ... Rib 14A ... Vertical rib 14B ... Horizontal rib
14C ... Intermediate rib 14D ... Connecting rib 15 ... Shielding cover 16 ... Electronic component 17 ... Lead wire

Claims (4)

The battery (2), the substrate (3) connected to the battery (2), and the substrate (3) disposed between the substrate (3) and the battery (2) are connected to the battery (2). In contrast, the substrate holder (4), the temperature sensor (5) for detecting the battery temperature, and the temperature sensor (5) and the battery surface are filled with the temperature sensor (5). A heat-bonding resin (6) that is thermally bonded to (2),
The substrate holder (4) disposed between the substrate (3) and the battery (2) has a notch (10) that opens in both the substrate (3) and the battery (2). The temperature sensor (5) is fixed to the substrate (3) so that it is located at the part (10), and the thermal bonding resin (6) is placed in the notch (10) where the temperature sensor (5) is arranged. A battery pack in which a temperature sensor (5) that is filled and fixed to a substrate (3) is thermally coupled to the surface of the battery.   The board (3), battery (2) and board holder (4) are housed in the case (1), and a shielding cover (15) is provided between the battery facing surface of the board (3) and the case inner surface, The battery pack according to claim 1, wherein the shielding cover (15) is brought into contact with the substrate (3) and the inner surface of the case to prevent the thermal bonding resin (6) from leaking to the surface of the substrate (3).   The substrate holder (4) is made of plastic, and the plastic substrate holder (4) is integrally formed with a rib (14) that contacts the battery (2) and the substrate (3). The battery pack according to claim 1, wherein a notch (10) is provided between (14). The battery pack according to claim 1, wherein the battery (2) is a thin battery, and a substrate (3) and a substrate holder (4) are disposed on a side surface of the battery (2).

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