Patent Application
20230140804
The present application relates to a battery pack, an electronic device, and an electric tool.
Various structures for connecting a battery and a circuit board have been proposed. For example, a structure is described where a circuit board is provided with a through hole, a battery is disposed in the through hole, and the circuit board and the battery are connected with a tab interposed therebetween.
The present application relates to a battery pack, an electronic device, and an electric tool.
Because the structure described in the Background section is a structure that has a circuit board provided with a through-hole, available batteries are limited to coin-type batteries. In addition, the mounting area of the circuit board is significantly reduced.
Accordingly, the present application provides a battery pack that has a configuration capable of appropriately connecting a battery that is larger in size than a coin-type battery and a circuit board, and an electronic device and an electric tool with the battery pack used according to an embodiment.
In an embodiment, the present application provides a battery pack including: an exterior case; a circuit board; a battery including a metal exterior can; and a metal member electrically connecting the battery and the circuit board, where an electrode part is provided on at least one end side of the battery, the circuit board and the electrode part are disposed to face each other, the metal member includes a board connection connected to the circuit board, an electrode connection connected to the electrode part, and a side part, the board connection is disposed to face the electrode connection with the side part interposed therebetween, and the board connection, the side part, and the electrode connection are integrally formed.
According to t an embodiment, the battery and the circuit board can be appropriately connected. It is to be noted that the contents of the present application are not to be construed as being limited by the effects illustrated in this specification.
Hereinafter, one or more embodiments will be described in further detail including with reference to the drawings. Preferred specific examples of the present application are described below, the contents of which are not to be considered limiting to the present application. It is to be noted that the members recited in the claims are not to be considered specified as members according to an embodiment. In particular, the scope of the present application is, unless otherwise described, not intended to be limited to only the dimensions, materials, and shapes of the constituent members described in the embodiments, the relative configurations thereof, and the description of directions such as upward, downward, leftward, and rightward directions, which are considered by way of illustrative example only. It is to be noted that sizes, positional relationships, and the like of the members illustrated in the respective drawings may be exaggerated for the clarity of description, and for preventing complicated illustrations, only some of reference numerals may be illustrated, or a part of the illustration may be simplified. Furthermore, in the following description, the same names and reference numerals represent the identical or same members, and redundant descriptions thereof will be appropriately omitted. Furthermore, for each element constituting the present application, an aspect may be employed such that one member also serves as multiple elements made of the same member, or conversely, the function of one member can be shared and achieved by a plurality of members.
First, for facilitating understanding of the present application according to an embodiment, problems to be considered will be described.
The above-described configuration requires a step of bending the metallic plate-shaped members 5A and 5B, and generates stress on the bent part of each metallic plate-shaped member. For this reason, as the process becomes complicated, there is a possibility that the bent part of each metallic plate-shaped member will be broken or cracked. In addition, for avoiding the contact between a mounted component on the circuit board 3 and the batteries 2A and 2B, it is necessary to dispose an insulating paper 6 between the circuit board 3 and the batteries 2A and 2B. In addition, a holder for holding the circuit board 3 or holding a space between the circuit board 3 and the batteries 2A and 2B is required.
Accordingly, a structure that applies no load to a metal member is desired without bending the metal member connecting the circuit board and the battery. In addition, an insulating member such as an insulating paper is preferably not provided from the viewpoint of allowing for reducing the manufacturing cost and simplifying the manufacturing process. In addition, the metal member preferably has a shape capable of achieving appropriate strength. An embodiment will be described in further detail in view of the foregoing respects.
A whole configuration example of a battery pack (battery pack 100) according to an embodiment will be described with reference to
As shown in
The battery unit 20 includes a battery 21A, a battery 21B, a circuit board 22, a bus bar 23A and a bus bar 23B, which are examples of metal members, an insulating paper 24, a ring-shaped insulating paper 25, and a relay connection member 26.
The batteries 21A and 21B are, for example, lithium ion batteries. The battery 21A and the battery 21B are, for example, batteries including electrode parts (positive electrode or negative electrode) at both end surfaces and including cylindrical metal exterior cans. According to the present embodiment, the batteries 21A and 21B are arranged so as to differ in polarity at adjacent ends.
The circuit board 22 is a board on which an IC (Integrated Circuit) or the like that performs charge/discharge control and protection control for the batteries 21A and 21B is mounted. Examples of the protection control include a protection function for preventing overcharge and overdischarge. The circuit board 22 has a predetermined circuit pattern and four terminal parts 221 formed, and the circuit pattern is connected to an appropriate terminal part. According to the present embodiment, the circuit board 22 has a rectangular shape, but may have another shape.
The bus bar 23A is a member that connects the circuit board 22 and a negative electrode terminal provided on one end side of the battery 21A. In addition, the bus bar 23B is a member that connects the circuit board 22 and a positive electrode terminal provided on one end side of the battery 21B. The bus bars 23A and 23B are made of a metal member in an appropriate shape.
The insulating paper 24 is a member disposed between the batteries for the purpose of insulation between the batteries 21A and 21B. In addition, the ring-shaped insulating paper 25 is a member disposed for the purpose of insulation between the positive and negative electrodes of the battery 21A and protection against migration.
The relay connection member 26 is a metallic member that connects the positive electrode terminal of the battery 21A and the negative electrode terminal of the battery 21B. The two batteries 21A and 21B are connected in series by the relay connection member 26. In addition, the relay connection member 26 includes a thin plate-shaped relay member 26A. The relay member 26A has an end connected to the circuit board 22. As illustrated in
Next, exemplary shapes of the circuit board 22 and bus bars 23A and 23B will be described in detail with reference to
As illustrated in
The circuit board 22 has one main surface 22A and a main surface 22B on the side opposite to the main surface 22A. The main surface 22A is provided with the above-described terminal parts 221 (terminal parts 221A to 221D). In addition, the main surface 22A is provided with a terminal part 224. The vicinity of the tip of the relay member 26A of the relay connection member 26 led through the notch 223 is connected to the terminal part 224.
Next, a configuration example of the bus bar 23A will be described with reference to
The bus bar 23A has a substantially quadrangular prism shape as a whole. Specifically, the bus bar 23A has a frame-shaped flange 231 on one end side. The flange 231 is an example of a board connection connected to the circuit board 22. As illustrated in
In addition, a protrusion 232 in a quadrangular prism shape is formed from the vicinity of the inner peripheral edge of the flange 231. The protrusion 232 has a rectangular sectional shape (sectional shape in the case of cutting the protrusion 232 along a plane that is substantially parallel to the extending direction of the flange 231). It is to be noted that the rectangular shape means a rectangular shape or a substantially rectangular shape. For example, if a corner is chamfered, the chamfered corner is as one corner. The protrusion 232 has four side parts corresponding to side surfaces and an end surface. According to an embodiment, side-part plates are disposed on all of the side parts, and an end-surface plate is disposed on the end surface. The side-part plates and the end-surface plate are, for example, metallic plate-shaped members. The end-surface plate disposed on the end surface of the protrusion 232 functions as an electrode connection 233. The flange 231 described above is extended perpendicularly from the side parts of the protrusion 232, and is disposed to face the electrode connection 233 with the side parts of the protrusion 232 interposed therebetween. In addition, the side parts of the protrusion 232 are erected substantially perpendicular to the electrode connection 233 from the peripheral edge (inner peripheral edge) of the flange 231. The electrode connection 233 is connected to a negative electrode terminal 211A of battery 21A by welding such as resistance welding or laser welding. According to an embodiment, the part between the flange 231 of the bus bar 23A and the electrode connection 233 has a quadrangular prism shape. In addition, for the bus bar 23A, the flange 231, the side parts of the protrusion 232, and the electrode connection 233 are integrally formed.
The electrode connection 233 has a slit formed. For example, the electrode connection 233 has a slit 233A formed to have an H-shape. The flange 231 of the bus bar 23B is solder-joined to the main surface 22B of the circuit board 22. In addition, the electrode connection of bus bar 23B is welded to a positive electrode terminal 211B of the battery 21B.
As illustrated in
The battery pack 100 described above has, for example, the following operational effects.
The circuit board 22 and the batteries 21A and 21B are connected by the bus bars 23A and 23B in the protruded shapes, thereby allowing a space to be provided between the circuit board 22 and the electrode parts of the batteries 21A and 21B, and allowing both to be prevented from coming into contact with each other. Accordingly, the need to use any insulating component is eliminated, thus allowing for reducing the number of components and allowing for reducing the manufacturing cost.
In addition, the protrusions of the bus bars 23A and 23B have a quadrangular prism shape. Thus, the bus bars 23A and 23B can be adjusted to have at least certain strength. Accordingly, at the time of impact due to dropping, the bus bars 23A and 23B serve as supports, thereby allowing the circuit board 22 and the electrode parts of the batteries 21A and 21B to be prevented from coming into contact with each other.
Furthermore, the electrode connections of the bus bars 23A and 23B are provided with the slits 233A. Thus, the electrode connections can be elastically deformed. The electrode connections are elastically deformed, thereby causing the electrode connections to follow the shape of the electrode part. Thus, the adhesion between the electrode connections and the electrode parts of the batteries can be enhanced, and the generation of defective welding at the time of welding can be reduced as much as possible. In addition, the electrode connections are elastically deformed, thereby allowing the absorption of the phase shift and dimensional error between the plurality of batteries, and allowing the generation of defective welding caused by the shift and the error to be avoided as much as possible. Furthermore, the electrode connections are elastically deformed, thereby allowing the flanges to be prevented from being detached from the circuit board due to a dropping impact.
Next, modification examples of the metal member will be described. The modification examples of the metal member, described below, can be applied to the above-described bus bars 23A and 23B. It is to be noted that the identical or same members or configurations to or as the members or the configurations described in accordance with an embodiment are denoted by the same reference numerals, and redundant descriptions thereof will be appropriately omitted.
A first modification example of the metal member will be described with reference to
As illustrated in
The electrode connection 313 has a slit 314 formed therein. As illustrated in
Next, a second modification example will be described with reference to
As illustrated in
The bus bars 33 differ from the bus bars 23A and 23B mainly in the shape of the flange and the shape of the protrusion. The bus bar 33 has a flange 331 formed in a C-shape. In addition, the bus bar 33 has a protrusion 332 protruded upward from the inner peripheral edge of the flange 331. The protrusion 332 has a configuration where side-part plates are disposed at the sites of three side parts among the four side parts of the protrusion 232 described in accordance with an embodiment, and has a sectional shape in a C-shape. In addition, the protrusion 332 has an electrode connection 333 that is an end-surface plate disposed on an end surface integrally connected to the three side parts. As illustrated in
Further, as illustrated in
It is to be noted that the bus bar, specifically, the protrusion preferably has an n-gonal prism shape (n = 4 in the present modification example), with prism shape is n. side-part plates disposed at sites corresponding to n/2 or more side parts, where the number of side parts of the n-gonal. In the case of a shape with side-part plates disposed at sites corresponding to less than n/2 side parts (for example, a shape with a side-part plate disposed on only one side part), the bus bar may be possibly bent by an impact due to welding or dropping. The shape with side-part plates disposed at sites corresponding to n/2 or more side parts, however, is employed, thereby making it possible to maintain a strength capable of preventing the bus bar from being bent against a load applied to the bus bar at the time of welding to the electrode part or at the time of a dropping impact.
In addition, as illustrated in
Next, a third modification example will be described with reference to
As illustrated in
As illustrated in
As illustrated in
It is to be noted that although it is not necessary to dispose the side-part plates on all of the six side parts of the protrusion 432, the protrusion 432 preferably, as described above, has an n-gonal prism shape (n = 6 in the present modification example), with side-part plates disposed at sites corresponding to n/2 or more, that is, 3 or more side parts, where the number of side parts of the n-gonal prism shape is n. For example, as illustrated in
Furthermore, as described above, as a configuration, side-part plates are preferably disposed at least on adjacent side parts. As illustrated in
Next, a fourth modification example will be described with reference to
As illustrated in
As illustrated in
As illustrated in
Further, although it is not necessary to dispose the side-part plate over the whole side part of the protrusion 532, the side-part plate is preferably disposed at a site corresponding to 1/2 or more of the total area of the side part. Thus, it is possible to maintain a strength capable of preventing the bus bar from being bent against a load applied to the bus bar at the time of welding to the electrode part or at the time of a dropping impact. For example, as illustrated in
Next, a fifth modification example will be described with reference to
As illustrated in
As illustrated in
As illustrated in
Further, although it is not necessary to dispose the side-part plate over the whole side part of the protrusion 632, the side-part plate is preferably disposed at a site corresponding to 1/2 or more of the total area of the side part. Thus, it is possible to maintain a strength capable of preventing the whole side-part plate from being bent against a load applied to the side-part plate at the time of welding to the electrode part or at the time of a dropping impact. For example, as illustrated in
It is to be noted that as long as the side-part plate is disposed at a site corresponding to 1/2 or more of the total area of the side part, there is no need for a single side-part plate like the side-part plate 632A illustrated in
While an embodiment of the present application has been described above, the contents of the present application are not to be considered limited thereto, and it is possible to make various modifications based on technical idea of the present application.
The metal exterior can of the battery may have the cylindrical shape described in an embodiment, or may have another shape, for example, an angular shape. In the case of the angular shape, the positive electrode terminal and the negative electrode terminal may be led out from the same end. More specifically, the positive electrode terminal and the negative electrode terminal may be provided at different ends as in the embodiment, or may be provided on the same end side.
The configurations of the circuit board, bus bar, and battery unit can be appropriately changed without departing from the scope of the present application. For example, the battery unit may have three or more batteries, and three or more bus bars may be used so as to correspond to the three or more batteries.
The matters described in the above-described embodiments and modification examples can be appropriately combined. In addition, the materials, processes, and the like described in the embodiments are considered merely by way of example, and the contents of the present application are not to be considered limited to the exemplified materials or the like.
The battery pack according to the present application can be used for mounting on various electronic devices such as a wireless phone, an electric tool, an electric vehicle, or the like, or for supplying electric power thereto.
Next, a specific application example will be described. For example, the above-described battery pack can be used as a power supply for a wearable device that has the function of a portable information terminal, that is, a so-called wearable terminal. Examples of the wearable terminal include, but not to be considered limited thereto, a wristwatch-type terminal and a glasses-type terminal.
As illustrated in
In the case of charging the battery pack 732, the positive electrode terminal 734A and negative electrode terminal 734B of the battery pack 732 are respectively connected to a positive electrode terminal and a negative electrode terminal of a charger (not shown). In contrast, in the case of discharging the battery pack 732 (in the case of using the wearable terminal 730), the positive electrode terminal 734A and negative electrode terminal 734B of the battery pack 732 are respectively connected to a positive electrode terminal and a negative electrode terminal of the electronic circuit 731.
The electronic circuit 731 includes, for example, a CPU, a peripheral logic unit, an interface unit, a storage unit, and the like, and controls the wearable terminal 730.
The battery pack 732 includes the battery pack according to an embodiment and a charge/discharge circuit 733 .
Next, an application example to which the battery pack according to the present application can be applied will be described. First, an example of an electric driver as an electric tool to which the present application can be applied will be schematically described with reference to
The battery pack 830 and the motor control unit 835 each may include a microcomputer (not shown), such that charge/discharge information of the battery pack 830 can be communicated with each other. The motor control unit 835 can control the operation of the motor 833, and cut off the power supply to the motor 833 at the time of abnormality such as overdischarge.
DESCRIPTION OF REFERENCE SYMBOLS
11:
22:
21A, 21B:
23A, 23B:
100:
211A:
211B:
231:
232:
233:
233A:
It should be understood that various changes and modifications to the presently preferred embodiments described herein will be apparent to those skilled in the art. Such changes and modifications can be made without departing from the spirit and scope of the present subject matter and without diminishing its intended advantages. It is therefore intended that such changes and modifications be covered by the appended claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2020-149544 | Sep 2020 | JP | national |
The present application is a continuation of PCT Application No. PCT/JP2021/031910, filed on Aug. 31, 2021, which claims priority to Japanese patent application no. JP2020-149544, filed on Sep. 7, 2020, the entire contents of which are herein incorporated by reference.
| Number | Date | Country | |
|---|---|---|---|
| Parent | PCT/JP2021/031910 | Aug 2021 | WO |
| Child | 18090980 | US |
