Battery pack

Abstract

To provide a battery pack for cordless power tools.SOLUTION: A battery pack is disclosed and includes a battery housing, a core housing disposed within the battery housing, at least one pouch cell disposed within the core housing, a flexible circuit extending along an inner surface of the core housing, and a temperature sensor operably coupled to the flexible circuit.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] (CROSS-REFERENCE TO RELATED APPLICATIONS) This application claims priority to U.S. Provisional Patent Application No. 63 / 430,585, filed December 6, 2022, the entire contents of which are incorporated herein by reference.

[0002] (Technical field) FIELD OF THE DISCLOSURE The present disclosure relates to cordless power tools, and more particularly to batteries for cordless power tools. [Background technology]

[0003] From DIY projects at home to large-scale commercial construction projects, cordless power tools are ubiquitous. These tools increase productivity and efficiency. These tools require battery packs that are constantly improving. Summary of the Invention [Means for solving the problem]

[0004] In one aspect, the present disclosure provides a battery pack including a battery housing, a core housing disposed within the battery housing, at least one pouch cell disposed within the core housing, a flexible circuit extending along an inner surface of the core housing, and a temperature sensor operably coupled to the flexible circuit.

[0005] In another aspect, the present disclosure provides a battery pack including a battery housing, a core housing disposed within the battery housing, at least one pouch cell disposed within the core housing, a flexible circuit extending along an outer surface of the core housing, a temperature sensor operably coupled to the flexible circuit, and a copper trace operably coupled to the temperature sensor and extending within the core housing.

[0006] In another aspect, the present disclosure provides a battery pack including a battery housing having an upper battery housing portion and a lower battery housing portion, a core housing disposed within the battery housing, and at least one pouch cell disposed within the core housing, wherein the core housing is made from a thermally conductive material.

[0007] Other features and aspects of the present disclosure will become apparent upon consideration of the following detailed description and accompanying drawings. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 2 is a perspective view of the battery pack. [Figure 2] FIG. 2 is a top plan view of the battery pack of FIG. [Figure 3] FIG. 2 is a bottom plan view of the battery pack of FIG. 1. [Figure 4] FIG. 2 is a side plan view of the battery pack of FIG. 1. [Figure 5] FIG. 2 is a rear plan view of the battery pack of FIG. 1. [Figure 6] FIG. 2 is a front plan view of the battery pack of FIG. 1. [Figure 7] FIG. 2 is a side plan view of the battery pack of FIG. 1 with the lower battery housing portion removed. [Figure 8] 2 is a side plan view of the battery pack of FIG. 1 with the lower battery housing portion and core housing removed. FIG. [Figure 9] 2 is a front perspective view of a core housing of the battery pack of FIG. 1 with the battery housing removed. FIG. [Figure 10] FIG. 2 is a partial cross-sectional view of the battery pack of FIG. [Figure 11] FIG. 10 is a partial view of another battery pack. [Figure 12] FIG. [Figure 13] FIG. 10 is a perspective view of another core housing. [Figure 14]FIG. 10 is a plan view of yet another core housing. [Figure 15] FIG. 10 is a plan view of yet another core housing. DETAILED DESCRIPTION OF THE INVENTION

[0009] Before describing any embodiments of the present disclosure in detail, it is to be understood that the disclosure is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings. The disclosure is capable of other embodiments and of being practiced or carried out in various ways. It is also to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting.

[0010] Features illustrated or described as part of one embodiment may be used with another embodiment to yield a still further embodiment. Accordingly, this disclosure is intended to cover such modifications and variations as come within the scope of the appended claims and their equivalents. The detailed description uses numbers and letters to refer to features in the drawings. Like or similar designations in the drawings and description are used to refer to like or similar parts of the disclosure.

[0011] As used herein, the terms “first,” “second,” and “third” can be used interchangeably to distinguish one component from another and are not intended to denote the location or importance of the individual components. The singular forms “a,” “an,” and “the” include plural references unless the context clearly dictates otherwise. Terms such as “coupled,” “fixed,” and “attached” refer to both direct coupling, fixing, or attachment, as well as indirect coupling, fixing, or attachment via one or more intermediate components or features, unless otherwise specified herein. As used herein, “comprises,” “comprising,” “including,” “has,” “having,” or any other variation thereof, are intended to cover a non-exclusive inclusion. For example, a process, method, article, or apparatus that includes a list of features is not necessarily limited to only those features and may include other features not expressly listed or inherent to such process, method, article, or apparatus. Furthermore, unless expressly stated to the contrary, “or” means an inclusive “or” and not an exclusive “or.” For example, condition A or condition B is satisfied by any one of the following: A is true (or exists) and B is false (or does not exist), A is false (or does not exist) and B is true (or exists), and both A and B are true (or exist).

[0012] Terms of approximation, such as "generally," "approximately," or "substantially," include values ​​within 10% greater than or less than the stated value. When used in the context of angles or directions, such terms include ranges within 10 degrees greater than or less than the stated angle or direction. For example, "generally perpendicular" includes directions within 10 degrees of perpendicular in any direction, e.g., clockwise or counterclockwise.

[0013] Benefits, other advantages, and solutions to problems are described below with respect to specific embodiments. However, the benefits, advantages, solutions to problems, and feature(s) that cause or may make the benefits, advantages, or solutions more noticeable should not be construed as key, essential, or required features of any or all claims.

[0014] 1-6, a battery pack 100 is shown. As shown, the battery pack 100 includes a battery housing 102 having an upper battery housing portion 104 coupled to a lower battery housing portion 106 along a seam 108, or interface, via a plurality of threaded fasteners 110 (e.g., screws). The upper battery housing portion 104 includes a top surface 112 and a tool body engagement assembly 114 extending therefrom. The tool body engagement assembly 114 includes a latch assembly housing 116 disposed on the upper battery housing portion 104 adjacent a first end 118 of the upper battery housing portion 104. A rail assembly 120 extends along the top surface 112 of the upper battery housing portion 104 from the latch assembly housing 116 adjacent a second end 122 of the upper battery housing portion 104. The rail assembly 120 includes a first rail 124 and a second rail 126 that extend along the length of the rail assembly 120 from a first end 128 of the rail assembly 120 to a second end 130 of the rail assembly 120 .

[0015] As shown, the rails 124, 126 extend outward from a central portion 132 of the rail assembly 120 away from a central axis 134 of the battery pack 100 such that the rails 124, 126 are parallel to the central axis 134. Each rail 124, 126 is generally shaped like an inverted "L" and is sized and shaped to fit complementary shaped features of a battery receptacle on a cordless power tool. The tool body engagement assembly 114 further includes a recess 136 that extends into the second end 130 of the rail assembly 120 and terminates in a plurality of terminal openings 138. When the battery pack 100 is engaged with a battery receptacle on a cordless power tool, the terminal openings 138 fit around one or more terminals within the cordless power tool, and the battery terminals within the terminal openings 138 are operably coupled to one another to transfer direct current (DC) power from the battery pack 100 to the cordless power tool to provide DC power to the motor and other electrical components within the cordless power tool.

[0016] The tool body engagement assembly 114 also includes a first latch 140 and a second latch 142 that are disposed within the latch assembly housing 116 and extend partially into the first end 128 of the rail assembly 120. The first latch 140 includes a hook 150 and a release button 152. The second latch 142 also includes a hook 154 and a release button 156. The first latch 140 and the second latch 142 are biased outwardly relative to the central axis 134 via one or more springs. During use, when the battery pack 100 is engaged with a battery receptacle of the cordless power tool, the hooks 150, 154 engage complementary features on the battery receptacle to hold the battery pack 100 engaged with the cordless tool. When the release buttons 152, 156 are pressed by a user, the hooks 150, 154 retract and the battery pack 100 can be removed from the cordless power tool by sliding the battery pack 100 out of the battery receptacle.

[0017] Referring to Fig. 7, the battery pack 100 includes a core housing 200 disposed within the battery housing 102. Furthermore, as shown in Fig. 8, a plurality of pouch cells 202 are disposed within the core housing 200. The pouch cells 202 are electrically coupled to one another. Adjacent pouch cells 202 are separated by plates 204, i.e., spacers. As shown in Fig. 9, the battery pack 100 further includes a printed circuit board assembly (PCBA) 206 disposed on the top of the core housing 200. The PCBA 206 includes a lower PCB 208 and an upper PCB 210 disposed thereon.

[0018] As shown, the battery pack 100 includes a flexible circuit 212 having a proximal end 214 and a distal end 216. The proximal end 214 of the flexible circuit 212 is electrically operably coupled to a connector 218, and the flexible circuit 212 extends downwardly from the connector 218 along an inner wall 220 of the core housing 200. In extending along the inner wall 220 of the core housing 200, the flexible circuit 212 also extends along an outer surface 222 of each of the plurality of pouch cells 202. FIG. 10 further shows that the battery pack 100 includes a temperature sensor 224 electrically operably coupled to the distal end of the flexible circuit 212. For example, the temperature sensor 224 is a thermistor. In one embodiment, the thermistor is a negative temperature coefficient (NTC) thermistor, which has an electrical resistance that decreases as the temperature increases. In another embodiment, the thermistor is a positive temperature coefficient (PTC) thermistor, which has an electrical resistance that increases as the temperature increases.

[0019] As further shown in FIG. 10 , a foam backing block 226 extends through an opening 228 in the sidewall of the core housing 200 and is aligned with the temperature sensor 224. The foam backing block 226 presses against the temperature sensor 224 to maintain alignment and engagement with the outer surface 222 of the pouch cell 202. The lower housing portion 106 includes one or more ribs 230 extending inward from an inner surface 232 of the lower housing portion 106. The ribs 230 are aligned with the openings 228 in the sidewall of the core housing 200. When the core housing 200 is installed within the lower battery housing portion 106, the ribs 230 press against the foam backing block 226, forcing it against the temperature sensor 224 and helping to maintain the temperature sensor 224 in place against the outer surface 222 of the pouch cell 202.

[0020] The temperature sensor 224 allows the temperature of the stack of pouch cells 202 to be accurate. Furthermore, the arrangement disclosed herein is relatively easy to assemble into a battery pack 100 and is relatively durable. The ribs 230 may be slanted or angled to facilitate assembly. The thermistor 224 and flexible circuit 212 reside within the core housing 200 and do not slide relative to the lower battery housing portion 106 during assembly.

[0021] 11 , a battery pack 300 includes a first pouch cell 302, a second pouch cell 304, a third pouch cell 306, a fourth pouch cell 308, and a fifth pouch cell 310 arranged in a stack. A PCBA 312 is disposed above the pouch cells 302, 304, 306, 308, and 310. A first flexible circuit 320 extends downward from a first connector 322 along the outer surfaces of the pouch cells 302, 304, 306, 308, and 310. In a particular embodiment, the first flexible circuit 320 is disposed outside the core housing in which the pouch cells 302, 304, 306, 308, and 310 are disposed and is disposed inside the lower battery housing portion, i.e., between the outer surface of the core housing and the inner surface of the lower battery housing portion in which the core housing is disposed.

[0022] As shown, the first flexible circuit 320 includes a first temperature sensor 324 and a second temperature sensor 326 disposed on the exterior of the core housing and the interior of the lower battery housing portion, i.e., between the exterior surface of the core housing and the interior surface of the lower battery housing portion in which the core housing is disposed. The temperature sensors 324, 326 are electrically operably connected to the first flexible circuit 320. The temperature sensors 324, 326 are, for example, thermistors. In one embodiment, the thermistors are negative temperature coefficient (NTC) thermistors, which have electrical resistance that decreases as temperature increases. In another embodiment, the thermistors are positive temperature coefficient (PTC) thermistors, which have electrical resistance that increases as temperature increases.

[0023] 11 shows that a first flexible circuit copper trace 328 is electrically operably coupled to the first temperature sensor 324 and extends from the first temperature sensor 324 to within a position within the core housing between the third and fourth pouch cells 306, 308. A second flexible circuit copper trace 330 is electrically operably coupled to the second temperature sensor 326 and extends from the second temperature sensor 326 to within a position within the core housing between the first and second pouch cells 302, 304.

[0024] As further shown, second flexible circuit 340 extends downward from second connector 342 along the exterior surfaces of pouch cells 302, 304, 306, 308, 310. In certain embodiments, second flexible circuit 340 is disposed external to the core housing in which pouch cells 302, 304, 306, 308, 310 are disposed and is disposed internal to the lower battery housing portion, i.e., between the exterior surface of the core housing and the interior surface of the lower battery housing portion in which the core housing is disposed.

[0025] As shown, the second flexible circuit 340 includes a third temperature sensor 344 and a fourth temperature sensor 346 disposed on the exterior of the core housing and the interior of the lower battery housing portion, i.e., between the exterior surface of the core housing and the interior surface of the lower battery housing portion in which the core housing is disposed. The temperature sensors 344, 346 are electrically operably connected to the second flexible circuit 340. The temperature sensors 344, 346 are, for example, thermistors. In one embodiment, the thermistors are negative temperature coefficient (NTC) thermistors, which have electrical resistance that decreases as temperature increases. In another embodiment, the thermistors are positive temperature coefficient (PTC) thermistors, which have electrical resistance that increases as temperature increases.

[0026] 11 shows that a third flexible circuit copper trace 348 is electrically operably coupled to the third temperature sensor 344 and extends from the third temperature sensor 344 to within a position within the core housing between the fourth and fifth pouch cells 308, 310. A fourth flexible circuit copper trace 350 is electrically operably coupled to the fourth temperature sensor 346 and extends from the fourth temperature sensor 346 to within a position within the core housing between the second and third pouch cells 304, 306. With this arrangement, the copper traces 328, 330, 348, 350 can transfer heat from the pouch cells 302, 304, 306, 308, 310 to the temperature sensors 324, 326, 344, 346 to provide highly accurate temperature data for the stack of pouch cells 302, 304, 306, 308, 310.

[0027] FIG. 12 shows another embodiment of a core housing 400 including a base plate 410. A first side wall 412 and a second side wall 414 extend perpendicularly from the base plate 410. The side walls 412, 414 are parallel to one another. A rear wall 416 extends perpendicularly from the base plate 410 between the side walls 412, 414. The rear wall 416 extends along the entire height of the side walls 412, 414 and is perpendicular to the side walls 412, 414. A front wall 418 also extends perpendicularly from the base plate 410 opposite the rear wall 416. The front wall 418 is parallel to the rear wall 416. Furthermore, the front wall 418 extends along only a portion of the height of the side walls 412, 414 such that an opening 420 is formed in the front wall 418 between the side walls 412, 414. A front end plate 422 is disposed within the opening 420 in the front wall 418. The core housing 402 may be formed from a thermally conductive plastic material and may have one or more metal features insert molded therein. These features may include one or more heat sinks, one or more metal fins, or a combination thereof. Additionally, the core housing 402 may be molded with one or more voids or openings in the base plate 410, side walls 412, 414, or rear wall 416 to provide ventilation and airflow for carrying heat away from one or more pouch cells disposed therein.

[0028] FIG. 13 shows another core housing 500 including a bottom plate 502 and a top plate 504 coupled via two rear standoffs 506 and a front standoff 508. The standoffs 506, 508 can be cylindrical posts, plates, rectangular posts, or a combination thereof. Furthermore, the standoffs 506, 508 can be made from aluminum. As shown, one or more doors 510, 512 are mounted on the front standoff 508. This arrangement provides a relatively strong structure for the fragile pouch cell. This arrangement also minimizes size and weight. The doors 510, 512 swing in and out for assembly. Furthermore, the doors 510, 512 can be made of plastic and can insulate the front standoff 508 from a pair of pouch cell tabs to prevent shorting.

[0029] 14 shows yet another core housing 600 including an outer housing 602 formed with multiple slot pairs 604 arranged horizontally along the same plane. A plate 606 with attached pouch cells 608 slides into each slot pair 604. This arrangement provides substantial clearance for pouch expansion and minimizes core stacking tolerances for overall height. In another embodiment, the slot pairs 604 may be arranged vertically.

[0030] 15 shows another core housing 700 having an outer housing 702 containing multiple pouch cells 704 disposed therein. The bottom 706 of the housing 702 is a heat sink made from aluminum or other material with high thermal conductivity. The core housing 700 may also include one or more thermally conductive inserts along the sides of the pouch cells 704.

[0031] Although the present disclosure has been described in detail with reference to certain preferred embodiments, variations and modifications exist within the scope and spirit of one or more independent aspects of the disclosure described.

Claims

1. a battery housing having an upper battery housing portion and a lower battery housing portion; a core housing disposed within the battery housing; at least one pouch cell disposed within the core housing; the core housing is made from a thermally conductive material; Battery pack.

2. The battery pack of claim 1 , wherein the bottom of the core housing is a heat sink.

3. The battery pack of claim 1 , wherein the core housing includes a bottom plate and a top plate joined by a plurality of standoffs.

4. The battery pack of claim 1 , wherein the core housing includes a plurality of slot pairs.

5. 5. The battery pack of claim 4, wherein the plates are installed in aligned pairs of slots.

6. The battery pack of claim 5 , wherein the pouch cell is disposed on the plate.

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