Rechargeable battery pack and method of manufacturing such battery pack

Abstract

A rechargeable battery pack includes a first battery cell holder and a second battery cell holder (62a, 62b), each of the first battery cell holder and the second battery cell holder having a set of cell holder terminals connected to the battery cell terminals and a set of circuit board terminals (64a, 64b) connected to the battery cell terminals, the set of circuit board terminals are arranged along circuit board connector terminal edges (66a, 66b) of the respective battery cell holders (62a, 62b). A circuit board terminal (64a), a terminal connection region of a circuit board (46), and circuit board connector terminal edges (66a, 66b) of battery cell holders (62a, 62b) are embedded in a coherent body (80) of potting resin. Gasket pressure ridges (78d) of the potting case (78) compress the potting gasket (52) such that the user interface element (48) and the wireless transceiver module (44) are not potted.

Description

Technical Field

[0001] The present invention relates to rechargeable batteries and methods of making such batteries. Background Art

[0002] Handheld power tools, such as chainsaws, have been around for the past 100 years or so. Most chainsaws are still powered by two-stroke internal combustion engines due to a trade-off between cost and weight versus power and operating time, but battery-powered chainsaws are becoming increasingly popular. However, the transition to battery power presents other challenges; for example, batteries must be able to withstand rough handling and operate in cold and wet climates. Summary of the Invention

[0003] The present invention aims to solve or at least alleviate some or all of the problems mentioned above. To this end, according to a first aspect, there is provided a rechargeable battery pack configured to be removably attached to a handheld battery-powered power tool, the rechargeable battery pack comprising: a plurality of elongated and rechargeable battery cells, each battery cell extending in a longitudinal direction between a pair of opposing battery cell ends, the pair of battery cell ends comprising battery cell terminals of opposite polarity; a circuit board comprising control electronics; a first battery cell holder configured to receive a first group of battery cell ends comprising one end of each of the plurality of battery cells, the first battery cell holder comprising a first group of battery cell holder terminals and a first group of circuit board terminals, the first group of battery cell holder terminals being connected to the battery cell terminals of the first group of battery cell ends, the first group of circuit board terminals being arranged along edges of circuit board connector terminals of the first battery cell holder. The battery pack further comprises a first set of circuit board terminals connected to a first terminal connection region of the circuit board; and a second battery cell holder configured to receive a second set of battery cell ends, including the other end of each of the plurality of battery cells, the second battery cell holder including a corresponding set of battery cell holder terminals and a second set of circuit board terminals connected to the battery cell terminals of the second set of battery cell ends, the second set of circuit board terminals being arranged along an edge of a circuit board connector terminal of the second battery cell holder, the second set of circuit board terminals being connected to the second terminal connection region of the circuit board, wherein the first battery cell holder is partially embedded in a continuous body of potting resin, wherein the first set of circuit board terminals, the first terminal connection region, and the edge of the circuit board connector terminal of the first battery cell holder are embedded in the continuous body of potting resin. In such a battery pack, both ends of each corresponding circuit board terminal are potted in the same continuous body of potting resin, even though the circuit board terminals may extend between separate structures of the battery pack. This reduces exposure to dust and moisture and reduces the risk of shorting of the circuit board terminals. It also stabilizes the mechanical relationship between the battery cell holder and the circuit board, thereby reducing the risk of electrical failure due to, for example, mechanical shock. Each of the first and second battery cell holders may include a respective plurality of slots configured to receive a respective first and second group of battery cell ends. Each slot may be configured to individually receive a respective single battery cell end; for example, an individual slot may have a cylindrical inner surface that mates with a cylindrical outer surface of a respective battery cell end. The cell holder terminals of each battery cell holder may connect the battery cells in a series or parallel configuration, or a combination of these configurations. The circuit board may include circuitry configured to control the charging and discharging of the battery cells.By only partially embedding the first battery cell holder in the potting resin, a battery pack with a lower weight can be obtained, which is particularly beneficial for handheld power tools. According to an embodiment, the continuous body of potting resin is homogeneous; such a body of potting resin can be obtained in a single potting step and also reduces defects such as irregularities or cavities that may appear in the interface between adjacent bodies of potting resin. The rechargeable battery cells can be, for example, of the lithium-ion type. They can be interconnected in groups to provide a maximum output voltage of the rechargeable battery pack, typically between 18 V and 94 V.

[0004] According to an embodiment, the second terminal connection area, the second set of circuit board terminals, and the edge of the circuit board connector terminals of the second battery cell holder can also be embedded in a continuous body of potting resin. This allows only a single continuous body of potting resin to protect both sets of circuit board terminals, which facilitates the manufacture of the battery pack. Alternatively, the battery pack can include two or more separate bodies of potting resin in which different parts of the battery pack are embedded. Similar to the first battery cell holder, the second battery cell holder can also be only partially embedded in the continuous body of potting resin, which can keep the weight low.

[0005] According to embodiments, at least some of the plurality of battery cells may be located outside the coherent body of potting resin. Typically, resins with low electrical conductivity also have low thermal conductivity. By positioning at least some of the plurality of battery cells outside the coherent body of potting resin, cooling of the battery cells may be improved. Preferably, all of the plurality of battery cells are located outside the coherent body of potting resin.

[0006] According to an embodiment, the rechargeable battery pack may include air gaps between adjacent battery cells. Preferably, air gaps exist between corresponding battery cells in several pairs of adjacent battery cells. More preferably, air gaps exist between corresponding battery cells in each pair of adjacent battery cells.

[0007] According to embodiments, the rechargeable battery pack may include an outer battery housing having a ventilation opening in fluid communication with the air gap. Preferably, the outer battery housing includes at least two ventilation openings in fluid communication with the air gap, wherein the at least two ventilation openings are at least 50 mm apart. This allows for a continuous flow of air through the rechargeable battery pack.

[0008] According to an embodiment, the circuit board may include an inner face facing the plurality of battery cells and an outer face facing away from the plurality of battery cells.

[0009] According to an embodiment, the inner face of the circuit board may be embedded in a coherent body of the potting resin.

[0010] According to embodiments, a rechargeable battery pack may include an electrical connector for connecting to a handheld battery-powered power tool and a set of connector leads extending between a circuit board and the electrical connector, wherein the connector leads extend from an inner face of the circuit board through a continuous body of potting resin. Such a configuration of the connector leads enables a compact arrangement of the connector leads and provides comprehensive protection for the connector leads against moisture and dust. The connector leads may be defined by one or more insulated cables.

[0011] According to an embodiment, an outer face of the circuit board may be at least partially embedded in a coherent body of the potting resin.

[0012] According to an embodiment, the coherent body of potting resin may be bonded to a potting shell which at least partially surrounds the coherent body of potting resin.

[0013] According to embodiments, the outer surface of the circuit board may include a user interface area and a potting gasket. The user interface area includes a plurality of user interface elements not covered by the continuous body of potting resin. The potting gasket surrounds the user interface area and abuts the continuous body of potting resin. The potting gasket is compressed by a gasket pressure ridge on the inner surface of the potting shell. Thus, the user interface area is not potted. The gasket pressure ridge may define a closed annular structure surrounding the entire user interface area.

[0014] According to embodiments, the potting shell can be provided with a potting shell opening aligned with the user interface area, wherein the user interface area is not covered by the continuous body of potting resin. Such an opening is particularly useful for user interface elements that require mechanical access, such as switches. Alternatively, the potting shell can be made of, for example, transparent plastic, thereby making, for example, LEDs within the user interface area visible from outside the potting shell.

[0015] According to embodiments, a rechargeable battery pack may include an outer battery housing having a gasket ridge extending through a potting case opening toward a circuit board, wherein a potting gasket is compressed by the gasket ridge of the outer battery housing. The potting gasket thus serves a dual purpose: retaining potting resin outside a user interface area to allow access to user interface elements, and sealing the user interface area from dust and moisture via the outer battery housing. The gasket ridge of the outer battery housing may define a closed annular structure that encloses the entire user interface area within the perimeter of the gasket ridge of the potting case. Alternatively or additionally, within the user interface area, the gasket ridge of the outer battery housing may define a closed annular structure surrounding individual user interface elements. The potting gasket may be configured as an adhesive film that is directly adhered to the circuit board. The plurality of user interface elements may include, for example, one or more light-emitting diodes and / or one or more switches, and / or a wireless transceiver module, such as a Bluetooth module, for example, a Bluetooth Low Energy (BLE) module.

[0016] According to embodiments, the potting gasket may include multiple gasket openings, each surrounding a corresponding user interface element, and the gasket ridges of the outer battery pack housing may compress the potting gasket in a closed ring structure surrounding the corresponding gasket openings. This minimizes water or dust leakage between different user interface elements. Furthermore, the separate slots defined by the gasket openings and the closed ring structure prevent stray light leakage, thereby improving the ability to distinguish between different LEDs positioned in different slots.

[0017] According to an embodiment, the potting gasket can be configured as a continuous foam rubber sheet. Such a gasket is inexpensive to manufacture. The foam rubber sheet can comprise a base polymer made from natural rubber and / or synthetic rubber (such as polyurethane). Preferably, the foam rubber sheet is a closed-cell rubber foam sheet.

[0018] According to embodiments, the circuit board may extend in the plane of the circuit board, and the total height of the continuous body of potting resin in a direction perpendicular to the plane of the circuit board may be less than 40 mm. This helps keep the weight of the rechargeable battery pack low. More preferably, the total height of the continuous body of potting resin in a direction perpendicular to the plane of the circuit board is less than 30 mm or less than 20 mm.

[0019] According to an embodiment, the cell holder terminals of the first set of cell holder terminals may be at least partially molded into the first battery cell holder. Such an arrangement provides a liquid-tight interface between the cell holder terminals of the respective cell holders. Optionally, the cell holder terminals of the second set of cell holder terminals are at least partially molded into the second battery cell holder. An exemplary suitable material for the battery cell holder is polybutylene terephthalate.

[0020] According to an embodiment, the first cell holder may have an outer face facing away from the battery cells and an inner face receiving the ends of the first group of battery cells, wherein the first cell holder is provided with a set of gaps aligned with the battery cell terminals at the ends of the first group of battery cells, these gaps exposing the first group of cell holder terminals on the outer face of the first cell holder. Thus, the cell holder terminals can be welded to the battery cell terminals at the ends of the first group of battery cells via these gaps. Optionally, similar to the first cell holder, the second cell holder has a corresponding outer face facing away from the battery cells and a corresponding inner face receiving the ends of the second group of battery cells, wherein the second cell holder is provided with a corresponding set of gaps exposing the second group of cell holder terminals on the outer face of the second cell holder.

[0021] According to an embodiment, the rechargeable battery pack may include a flexible cell holder cover that is located on the outside of the first cell holder, the cell holder cover covering a set of gaps that expose the first group of cell holder terminals on the outside of the first cell holder. Thereby, the cell holder cover can protect the outside of the first group of cell holder terminals from dust, moisture and water. The cell holder cover can be configured as an adhesive film that is directly adhered to the outside of the first cell holder. The cell holder cover can be a first cell holder cover, and optionally, the rechargeable battery pack may further include a flexible second cell holder cover that is located on the outside of the second cell holder and covers a set of gaps that expose the first group of cell holder terminals.

[0022] According to an embodiment, the first cell holder cover may be a foam rubber sheet. The foam rubber sheet may include a base polymer made of natural rubber and / or a synthetic rubber (such as polyurethane). Preferably, the foam rubber sheet is a closed-cell rubber foam sheet. The foam rubber sheet may be partially compressed between the first cell holder and the outer battery pack housing of the battery to further improve the fluid tightness and / or absorb mechanical tolerances between the first cell holder and the outer battery pack housing. Depending on the circumstances, any second cell holder cover may be a foam rubber sheet configured and positioned according to the first cell holder cover (with appropriate modifications).

[0023] According to a second aspect, a rechargeable battery pack is provided, which is configured to be removably attached to a handheld battery-powered power tool, and the rechargeable battery pack can be optionally configured according to any of the above-mentioned embodiments, and the rechargeable battery pack includes: a plurality of slender and rechargeable battery cells; a circuit board, including control electronic devices, the circuit board including a user interface area, the user interface area including a wireless transceiver module, wherein the circuit board is partially embedded in a coherent body of potting resin, and wherein the user interface area is not covered by the coherent body of potting resin; and a potting gasket, adjacent to the coherent body of potting resin and separating the user interface area from the coherent body of potting resin, wherein the wireless transceiver module is separately overmolded with a plastic overmolding body, wherein the plastic overmolding body includes a sealing ridge extending into a closed annular structure on the bottom surface of the wireless transceiver module, the sealing ridge sealingly adjacent to the circuit board. Combining a potting gasket that keeps the user interface area from being potted with a separate overmold having an integrated sealing ridge for the wireless transceiver module allows the wireless transceiver module to be removed from the circuit board while still achieving a high degree of dust and water protection. This facilitates, for example, upgrading the wireless transceiver module to a newer version. Preferably, the plastic overmold leaves the antenna of the wireless transceiver module exposed. According to an embodiment, the plastic overmold can be made of a plastic with a Shore D hardness exceeding 10; this can facilitate manufacturing. The plastic overmold can be made of a thermoplastic material such as polyamide. According to an embodiment, the wireless transceiver module can be a Bluetooth module, such as a Bluetooth Low Energy (BLE) module.

[0024] According to embodiments, the bottom surface of the wireless transceiver module may include a set of connection terminals that are connected to, but not soldered to, a set of mating connection terminals on the circuit board. The wireless transceiver module is biased against the circuit board. This ensures a high degree of tightness of the sealing ridge and facilitates replacement of the wireless transceiver module. Specifically, the bias may slightly compress the sealing ridge. The bias may be generated by pressing the wireless transceiver module against the circuit board using one or more screws. According to embodiments, the wireless transceiver module may be provided with a set of screw holes for mounting screws.

[0025] According to a third aspect, a rechargeable battery pack is provided, which is configured to be removably attached to a handheld battery-powered power tool, and the rechargeable battery pack can optionally be configured according to any of the above-mentioned embodiments, the rechargeable battery pack comprising: a plurality of rechargeable battery cells; and a circuit board including control electronics, wherein the circuit board comprises an inner face facing the plurality of battery cells and an outer face facing away from the plurality of battery cells, wherein the outer face of the circuit board comprises a user interface area, the user interface area comprising a plurality of user interface elements, wherein the outer face of the circuit board The circuit board is partially embedded in a coherent body of potting resin, which is coupled to a potting case, which at least partially surrounds the outside of the circuit board and the coherent body of potting resin, wherein the potting case is provided with a potting case opening aligned with the user interface area, and the user interface area is not covered by the coherent body of potting resin, the rechargeable battery pack also includes a potting gasket, which surrounds the user interface area and is adjacent to the coherent body of potting resin, the potting gasket being pressed between the circuit board and a gasket pressure ridge on the inner face of the potting case, wherein the gasket pressure ridge defines a closed annular structure extending around the potting case opening.

[0026] According to an embodiment, a rechargeable battery may include an outer battery casing provided with a gasket pressing ridge extending through the potting shell opening toward the circuit board, wherein the potting gasket is compressed by the gasket pressing ridge of the outer battery casing.

[0027] According to a fourth aspect, there is provided a combination of a rechargeable battery pack according to any one of the preceding aspects or claims and a handheld battery-powered power tool, the handheld battery-powered power tool comprising a battery connector adapted to be connected to the rechargeable battery pack.

[0028] According to a fifth aspect, a method for manufacturing a rechargeable battery pack is provided, comprising: providing a circuit board, a first battery cell holder, a second battery cell holder, and a plurality of battery cells, the first battery cell holder comprising a corresponding set of circuit board terminals arranged along an edge of a circuit board connector terminal of the first battery cell holder, the second battery cell holder comprising a corresponding set of circuit board terminals arranged along an edge of a circuit board connector terminal of the second battery cell holder; positioning a first set of battery cell ends of the plurality of battery cells in the first battery cell holder; positioning a second set of battery cell ends of the plurality of battery cells in the second battery cell holder; positioning the circuit board to align with the first battery cell holder and the second battery cell holder. The method comprises placing edges of the circuit board connector terminals adjacent to each other, such that the inner surface of the circuit board faces the plurality of battery cells and the outer surface of the circuit board faces away from the plurality of battery cells; electrically connecting the circuit board terminals of the first and second battery cell holders to the circuit board; placing the circuit board and the edges of the circuit board connector terminals of the first and second battery cell holders in a potting shell shaped like a tray, wherein the outer surface of the circuit board faces downward and the first and second battery cell holders extend upward from the potting shell; and filling the potting shell with potting resin to form a coherent body of potting resin in which the edges of the circuit board connector terminals of the first and second battery cell holders are at least partially embedded. This allows for a dust-proof and waterproof interface between the circuit board and the battery cell holders to be achieved in a simple and inexpensive manner. These method steps do not need to be performed in the order described above. According to embodiments, a potting gasket can be snapped onto the battery cell holder, for example, using a cantilever hook, before the potting shell is filled with potting resin. The potting shell can define a portion of the outer shell of the rechargeable battery pack.

[0029] According to an embodiment, the method may include: prior to filling the potting case with potting resin, positioning a potting gasket between the circuit board and the potting case, the potting gasket surrounding a user interface region and / or a transceiver mounting region of the circuit board; and compressing the potting gasket by pressing the circuit board against the potting case such that when the potting resin is filled into the potting case, the potting gasket prevents the potting resin from reaching the user interface region and / or the transceiver mounting region. The potting case may be provided with a potting case opening aligned with the user interface region and / or the transceiver mounting region.

[0030] According to embodiments, the potting case may be provided with a potting case opening aligned with the user interface area and / or the transceiver mounting area, wherein the method may further include: providing an outer battery housing; compressing the potting gasket by pressing the outer battery housing against the potting gasket within a perimeter of the potting case opening, such that a sealing engagement is achieved between the outer battery housing and the circuit board via the potting gasket; and securing the outer battery housing relative to the circuit board. The compressing and securing steps may be performed simultaneously, for example, by moving the outer battery housing toward the circuit board using attachment screws.

[0031] According to an embodiment, the method may include: welding a set of cell holder terminals of a first battery cell holder to battery cell terminals at the ends of a first set of battery cells via a set of gaps through the first cell holder; welding a set of cell holder terminals of a second battery cell holder to battery cell terminals at the ends of a second set of battery cells via a set of gaps through the second cell holder; applying a flexible first cell holder cover to the exterior of the first cell holder to cover the set of gaps through the first cell holder; and applying a flexible second cell holder cover to the exterior of the second cell holder to cover the set of gaps through the second cell holder. Again, these method steps do not have to be performed in the order described above.

[0032] It should be noted that embodiments of the present invention can be implemented with all possible combinations of the features recited in the claims. Furthermore, it should be understood that the various embodiments described for the apparatus according to the first aspect can be combined with the apparatus according to the second and third aspects, and vice versa. Similarly, the various embodiments described for the apparatus according to the first, second, third, and fourth aspects can be combined with the method according to the fifth aspect, and vice versa. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The above and additional objects, features and advantages of the present invention will be better understood through the following illustrative and non-limiting detailed description of preferred embodiments of the present invention, with reference to the accompanying drawings, in which like reference numerals are used for similar elements, and in which:

[0034] Figure 1 is a plan view of a handheld battery-powered chainsaw viewed from the side, the chainsaw retaining a rechargeable battery pack;

[0035] Figure 2 yes Figure 1 A perspective view of a chainsaw in FIG. 1 showing the connection of a battery pack to the chainsaw;

[0036] Figure 3 Observed from the first perspective Figures 1 to 2 A view of the battery pack in the;

[0037] Figure 4 Observed from a second perspective Figures 1 to 2 A view of the battery pack in the;

[0038] Figure 5A yes Figures 1 to 4 a perspective view of an internal portion of a wireless transceiver module of a battery pack;

[0039] Figure 5B yes Figures 1 to 4 A perspective view of a wireless transceiver module in a battery pack;

[0040] Figure 5C Observed from below Figure 5B A perspective view of a wireless transceiver module;

[0041] Figure 6 It's about Figures 1 to 4 Exploded view of the circuit board of the battery pack, which includes Figures 5A to 5C The transceiver module in

[0042] Figure 7 yes Figures 1 to 4 An exploded view of the battery cell assembly of the battery pack;

[0043] Figure 8A yes Figure 7 A perspective view of a battery cell holder of a battery cell assembly;

[0044] Figure 8B yes Figure 8A A perspective view of a set of cell holder terminals of a battery cell holder in FIG.

[0045] Figure 9 yes Figures 1 to 4 A perspective view of a subassembly of a battery pack, the subassembly comprising Figure 7 Battery cell components and Figure 6 The circuit board in the figure shows the battery cell assembly without the battery cell holder;

[0046] Figure 10A It is a potting shell and Figure 9 A perspective view of the subassemblies in FIG. 1 before being connected to each other;

[0047] Figure 10B yes Figure 10B A perspective view of the subassembly and the potting shell after they are connected to each other;

[0048] Figure 11A Before filling the potting resin into the potting shell Figure 10B a cross section of the subassembly and potting case in the battery cell assembly, the cross section being taken along a plane perpendicular to the circuit board and parallel to the longitudinal axis of the battery cell of the battery cell assembly;

[0049] Figure 11B After the potting resin is filled in the potting shell Figure 11A The cross section corresponding to the view;

[0050] Figure 12 This is a view from the bottom after the potting resin is filled into the potting shell. Figure 10B A perspective view of the subassembly and potting shell in FIG;

[0051] Figure 13 yes Figures 1 to 4 A perspective view of the main housing cover of the battery pack;

[0052] Figure 14 yes Figures 1 to 4 A perspective view of the final assembly step of the battery pack, wherein Figure 12 The subassembly and potting shell inserts include Figure 13 a main housing cover in the battery pack housing;

[0053] Figure 15 yes Figures 1 to 4 The cross section of the battery pack is along Figure 3 , and the battery pack is shown with potting omitted; and

[0054] Figure 16 It shows the manufacturing Figures 1 to 4 A flow chart of a method for a battery pack in a vehicle.

[0055] All figures are schematic, not necessarily to scale, and generally only show parts which are necessary in order to elucidate the embodiments, wherein other parts may be omitted. DETAILED DESCRIPTION

[0056] Figure 1A handheld battery-powered power tool embodied as an electric chain saw 10 is shown. The power tool 10 includes a power unit body 12 provided with a pair of handles 14a, 14b by means of which an operator (not shown) can hold and operate the power tool 10. The pair of handles includes a front handle 14a, which is typically intended for left-handed grip, and a rear handle 14b, which is typically intended for right-handed grip. The rear handle 14b is positioned on top of the power unit body 12, i.e., the exemplary chain saw 10 is of a so-called top-handle type; however, it should be understood that the teachings herein are equally applicable to rear-handle chain saws and other types of handheld battery-powered power tools. The power unit body 12 holds and operates a working assembly, which in the illustrated case is configured as a cutting assembly including a saw chain 16 and an elongated guide bar 18 for guiding the saw chain 16 along an elongated circular path. The cutting assembly extends from a front end of the power unit body 12 in a longitudinal direction L. The power tool 10 also includes a removable rechargeable battery pack 20, an electric motor 22 (only in the case of a removable rechargeable battery pack), and a rechargeable battery pack 20. Figure 1 The power tool 10 also includes a controller 26 (shown schematically in FIG. 1 ) and a finger-operated trigger 24 that allows the operator to control the flow of power from the battery pack 20 to the electric motor 22. Thus, the operator can selectively utilize the electric motor 22 to move the saw chain 16. Figure 1 14b), the controller is configured to control the electric motor 22 based on input from a trigger 24. The trigger 24 extends downward from the bottom surface of the rear handle 14b and is movable between a released position (shown) in which the saw chain 16 is not moved and a fully depressed position (not shown) in which the electric motor 22 is operated in response to the fully depressed position to move the saw chain 16.

[0057] Now refer to Figure 2 The power unit body 12 includes a battery compartment 28 shaped to receive and enclose the battery pack 20. The battery compartment 28 is provided with a battery connector 30 configured to releasably couple to a mating power tool connector ( Figure 2 ), for transmitting power to the electric motor 22 ( Figure 1 The battery pack 20 can be inserted into the battery compartment 28 of the power unit body 12 along an insertion direction C, which is perpendicular to the guide plate 18 in the example shown ( Figure 1 ). The insertion direction C also defines a connection direction for connecting the power tool connector of the battery pack 20 to the battery connector 30 of the power tool 10.

[0058] Figure 3The battery pack 20 is shown in more detail. The battery pack 20 includes an outer battery pack housing 32 provided with a first ventilation opening 34a for air cooling the components within the battery pack housing 32. The battery pack 20 also includes a battery connector 20 ( Figure 2 ) power tool connector 36. The battery pack housing 32 can include several separate housing parts; in the illustrated example, the battery pack housing 32 includes a main housing 32a, a main housing cover 32b, and a power tool connector cover 32c. The battery pack 20 also includes a user interface 38 having an indicator light 40 and a button 42.

[0059] Figure 4 The battery pack 20 is shown from another angle, showing the first ventilation opening 34a ( Figure 3 ) opposite the second ventilation opening 34b. This allows air to flow continuously from the first ventilation opening 34a through the battery pack 20 to the second ventilation opening 34b, or vice versa. The air flow can be controlled by the power unit body 12 ( Figure 1 ) or generated by a fan within the battery pack 20 itself.

[0060] The battery pack 20 incorporates several technical solutions that operate in conjunction with one another to make the battery pack 20 waterproof and easy to manufacture and maintain. Figures 5A to 5C A short-range wireless transceiver module implemented as a Bluetooth low energy transceiver is shown, which is specially adapted for use with a battery pack in a manner that will be further elucidated below.

[0061] from Figure 5A Initially, the wireless transceiver module 44 includes communication circuitry 44a that communicates via a radio antenna 44b etched onto a printed circuit board. Figure 5B , the communication circuit 44a is separately overmolded with a plastic overmolding body 44c, which is Figure 5A 44a . The plastic overmold 44c is made of a polyamide having a Shore D hardness of approximately 40. An exemplary suitable material for the plastic overmold 44c is TECHNOMELT PA 2035 BLACK, available from Henkel. When viewed from above, the plastic overmold 44c completely encapsulates the communication circuitry 44a while allowing the radio antenna 44b to extend from the plastic overmold.

[0062] Figure 5CThe bottom surface of wireless transceiver module 44 is shown. Plastic overmold 44c includes a sealing ridge 44d extending in a closed annular configuration on the bottom surface of wireless transceiver module 44. Sealing ridge 44d extends in the plane of the sealing ridge and surrounds an electrical connector area 44e, where wireless transceiver module 44 includes a set of electrical connectors 44f for connecting to a circuit board (not shown). Electrical connectors 44f are spring-type for resiliently and releasably abutting connector contacts against the circuit board, which are positioned generally in the plane of the sealing ridge. Screw holes 44g penetrate wireless transceiver module 44.

[0063] Figure 6 A circuit board 46 is shown that includes control electronics configured to operate a battery management system BMS. The BMS is configured to control the battery pack 20 ( Figure 1 ) and the battery cells (not shown) in the power tool 10 ( Figure 1 ) and between the battery pack 20 and a battery charger (not shown). The circuit board 46 extending in the circuit board plane P is accommodated in the outer battery pack housing 32 ( Figure 3 ), and the circuit board has an inner surface 46a facing the battery cells and an outer surface 46b facing away from the battery cells. The circuit board 46 includes a first terminal connection area 46c and a second terminal connection area 46d, each of which includes a set of connection contacts 46e configured to electrically connect to the battery terminals of the battery cells. The outer surface 46b of the circuit board 46 includes a user interface area 46f, which includes a plurality of user interface elements 48, which are implemented in this case as micro switches 48b and a set of light-emitting diodes 48a.

[0064] The wireless transceiver module 44 is screwed to the circuit board 46 using screws 50 so that the screws 50 bias the wireless transceiver module 44 against the circuit board 46. As a result, the sealing ridge 44d ( Figure 5C ) are compressed by biasing and sealingly abut the circuit board 46. In addition, the electrical connectors 44f of the wireless transceiver module 44 are biased against the circuit board 46 so that they are electrically connected to connection contacts (not shown) in the wireless transceiver module connection area 46g within the transceiver mounting area 46h of the circuit board 46.

[0065] A potting gasket 52 made of foam rubber is positioned on the circuit board 46 so that the potting gasket surrounds the user interface area 46f and the wireless transceiver module connection area 46g. The potting gasket 52 also includes a gasket hole 52b and a plurality of gasket holes 52a. The gasket hole 52b receives the wireless transceiver module 44, and the plurality of gasket holes 52a each receives a corresponding user interface element of the user interface elements 48.

[0066] A set of connector leads 54 configured as an insulated cable connects between the circuit board 46 and the power tool connector 36 ( Figure 3 ). Corresponding ones of the connector leads 54 are configured to transmit power from the battery cells to the power tool 10 and to communicate with the power tool 10. The connector leads extend from the inner face 46a of the circuit board 46.

[0067] Figure 7 It is a battery pack 20 ( Figure 3 ). The battery cell assembly 21 includes a plurality of elongated lithium-ion rechargeable battery cells 56. Each battery cell 56 extends in a longitudinal direction B between a first battery cell end 58a and a second battery cell end 58b. The battery cell ends 58a, 58b include battery cell terminals 60a, 60b of opposite polarity. One battery cell 56 (e.g., battery cell 56a) has a positive battery cell terminal at its first battery cell end 60a and a negative battery cell terminal at its second battery cell end 60b, while the other battery cells 56 (e.g., battery cell 56b) have a negative battery cell terminal at their first battery cell end 58a and a positive battery cell terminal at their second battery cell end 60b.

[0068] The first battery cell holder 62a receives the first ends 58a of the plurality of battery cells 56, and the second battery cell holder 62b receives the second ends 58b of the plurality of battery cells 56 to securely hold the battery cells together. The first battery cell holder 62a includes a first set of cell holder terminals 63a that are electrically connected to the battery cell terminals 60a at the first set of battery cell ends 58a and to a first set of circuit board terminals 64a arranged side by side along a circuit board connector terminal edge 66a of the first battery cell holder 62a. Similarly, the second battery cell holder 62b includes a second set of cell holder terminals 63b that are electrically connected to the battery cell terminals 60b at the second set of battery cell ends 58b and to a second set of circuit board terminals 64b arranged side by side along a circuit board connector terminal edge 66b of the second battery cell holder 62b.

[0069] The first battery cell holder 62a (which is a plastic component molded from, for example, polybutylene terephthalate) has an outer face 68a facing away from the battery cells 56 and an inner face 70a that receives the first set of battery cell ends 58a. To this end, the inner face 70a defines a plurality of circular grooves 72 (as seen on the second battery cell holder 62b, with appropriate modifications) that are sized to snugly receive the first set of battery cell ends 58a. The first set of cell holder terminals 63a are partially molded into the first battery cell holder 62a, but the terminals 63a are exposed on the inner face 70a of the battery cell holder 62a via a set of battery cell terminal connection gaps 74 (as seen on the second battery cell holder 62b, with appropriate modifications), thereby enabling the first set of cell holder terminals 63a to be electrically connected to the first set of battery cell terminals 60a. The first set of cell holder terminals 63a are also exposed on the outer face 68a of the cell holder 62a via a set of welding gaps 75, which enables the first set of cell holder terminals 63a to be welded to the first set of battery cell terminals 60a from the outside. Similarly, the second battery cell holder 62b has a corresponding outer face 68b facing away from the battery cells 56 and a corresponding inner face 70b that receives the second set of battery cell ends 58b, and the inner face 70b defines a plurality of circular grooves 72 that matingly receive the second set of battery cell ends 58b. The second set of cell holder terminals 63a are partially molded into the second battery cell holder 62b, but are exposed on the inner face 70a of the battery cell holder 62a via a set of battery cell terminal connection gaps 74, thereby enabling the second set of cell holder terminals 63b to be electrically connected to the second set of battery cell terminals 60b. In addition, the second set of cell holder terminals 63b are exposed on the outer side 68b of the battery cell holder 62b via a set of weld gaps that are similar to the weld gaps 75 of the first battery cell holder 62a. The grooves 72 can be shaped to sealably receive the battery cell ends 58a, 58b to prevent dust and moisture from penetrating from the inner surface of the battery cell holders 62a, 62b to the battery cell terminals 60a, 60b. The circuit board connector terminal edges 66a, 66b of the battery cell holders 62a, 62b are provided with cantilevered hooks 77a, 77b.

[0070] Figure 8A The first battery cell holder 62a is shown at a greater magnification, and Figure 8B A first set of cell holder terminals 63a are shown molded into the battery cell holder 62a.

[0071] Figure 9 The battery pack 20 ( Figure 3 ) subassembly, wherein the battery cell holders 62a, 62b are omitted ( Figure 7), to show welding to battery cell terminals 60a, 60b ( Figure 7 ) of the first set of cell holder terminals 63a and the second set of cell holder terminals 63b, thereby connecting the subgroups of the plurality of battery cells 56 in parallel and in series. The first set of circuit board terminals 64a is soldered to the corresponding connection contacts 46e ( Figure 6 ), and the second set of circuit board terminals 64b are soldered to the corresponding connection contacts 46e of the second terminal connection region 46e of the circuit board 46 ( Figure 6 ). Figure 9 Also shown is a circuit board 46 with a wireless transceiver module 44 attached, and a potting gasket 52 positioned on the circuit board 46. The potting gasket 52 is configured as a flexible sheet made of closed-cell polyurethane foam rubber provided with an adhesive film for direct attachment to the outer face 46b of the circuit board 46.

[0072] Return Reference Figure 7 After welding the multiple sets of cell holder terminals 63a, 63b to the battery cell terminals 60a, 60b, the outer surfaces 68a, 68b of the cell holders 62a, 62b are covered with corresponding cell holder covers 76a, 76b. The cell holder covers 76a, 76b are configured as flexible sheets made of closed-cell polyurethane foam rubber and provided with an adhesive film for direct attachment to the outer surfaces 68a, 68b of the corresponding cell holders 62a, 62b.

[0073] Figure 10A The battery pack 20 ( Figure 3 ) of the subassembly 23, which includes a subassembly connected to the circuit board 46 Figure 7 The battery cell assembly 21 is in a potting preparation state. Figure 10A Also shown is a potting case 78 shaped like a tray. The potting case 78 has an inner surface 78 a that faces the circuit board 46 during potting, and an outer surface 78 b that faces away from the circuit board. The potting case 78 also includes a potting case opening 78 c surrounded by a gasket ridge 78 d on the inner surface 78 a. Prior to potting, the subassembly 23 is flipped over and placed into the potting case 78 with the circuit board facing downward, wherein the potting case opening 78 c is aligned with the user interface area 46 f ( Figure 6 ) and transceiver installation area 46h ( Figure 6 ) are aligned. Thereafter, the circuit board 46 is pressed against the potting case 78 so that the gasket pressing ridge 78d is aligned along the area around the user interface 46f ( Figure 6 ) and wireless transceiver module 44 ( Figure 6) The sealing line extending into a closed annular structure compresses the potting gasket. When the potting gasket 52 is in the compressed state, the cantilever hooks 77a, 77b interlock with the matching structures 79a, 79b on the outer surface 78b of the potting shell 78, thereby fixing the position of the circuit board 46 relative to the potting shell 78. Finally, when the potting gasket 52 is in the compressed state, the cantilever hooks 77a, 77b interlock with the matching structures 79a, 79b on the outer surface 78b of the potting shell 78, thereby fixing the position of the circuit board 46 relative to the potting shell 78. Figure 10B , a potting resin is injected into the potting shell 78 from above (eg, at the position indicated by arrow 81), and the potting resin is allowed to cure. Figure 10A ) prevents the potting resin from leaking through the potting case opening 78c and allows the user interface area 46f and the transceiver mounting area 46h ( Figure 6 ) is not covered by the potting resin. An exemplary suitable potting resin for this application is a polyurethane based potting resin, such as WEVOPUR 552FL available from WEVO-CHEMIE GmbH.

[0074] Figure 11A and Figure 11B The cross section schematically shows the Figure 11A ) and after potting ( Figure 11B ) of the subassembly 23 having the potting shell 78. Figure 11B In the embodiment, the circuit board 46 and the first and second battery cell holders 62a and 62b are partially embedded in a continuous and homogeneous body 80 of potting resin. More specifically, the first and second sets of circuit board terminals 64a and 64b ( Figure 7 )、first terminal connection region 46c and second terminal connection region 46d ( Figure 6 ), the circuit board connector terminal edges 66a, 66b of the battery cell holders 62a, 62b ( Figure 7 ), the inner surface 46a of the circuit board 46 ( Figure 6 ), the outer surface 46b of the circuit board 46 ( Figure 6 ) and the portion of the connector lead 54 adjacent to the circuit board 46 ( Figure 6 ) is embedded in the body 80 of potting resin. The potting shell 78 is bonded to the body 80 of potting resin and will remain in the final product, ie, in the battery pack 20 ( Figure 3 )middle.

[0075] At the same time, and now refer to Figure 12 , the user interface area 46f with the user interface elements 48 and the wireless transceiver module 44 are not covered by the potting resin. Figure 11B , the battery cell 56 and the main part of the battery cell holder 62a, 62b are not covered by the potting resin. Specifically, the battery cell 56 is located outside the main body 80 of the potting resin so that the first ventilation opening 34a and the second ventilation opening 34b ( Figure 3 and Figure 4 ) can pass through the air gaps 82 between adjacent battery cells 56. The total height H of the main body 80 of the potting resin in a direction perpendicular to the plane P of the circuit board is approximately 15 mm.

[0076] Figure 13 The battery pack housing 32 ( Figure 3 ) on the inner surface of the main housing cover 32b. The main housing cover 32b includes a gasket pressure ridge 84. Figure 12 The subassembly 23 is positioned on the cover 32 ( Figure 3 ) in the inner portion, the shape of the gasket ridge is designed to be aligned with the user interface area 46f ( Figure 6 ) aligns with and surrounds the user interface area. The outer perimeter 84a of the gasket ridge 84 is shaped to surround the entire user interface area 46f, but the inner section of the gasket ridge 84b is also defined for receiving the user interface element 48 ( Figure 6 ) in a separate slot 86 for a corresponding user interface element in the main housing cover 32b. The switch push portion 49a is disposed on the inner face of a cantilevered element integrally formed with the main housing cover 32b and positioned to align with the micro switch 48b when the battery pack 20 ( FIG. 20 ) is fully assembled; the cantilevered element 49b is positioned in a manner similar to the embodiment of FIG. Figure 14 Instructions.

[0077] Figure 14 Shown Figure 12 Positioning of the subassembly 23 in the battery pack housing 32. The subassembly 23 slides into the main housing 32a, thereby separating the cell holder covers 76a, 76b (between the cell holders 62a, 62b and the main housing 32a) Figure 7 ) is slightly compressed. Thereafter, main housing cover 32b is placed on top of potting shell 78, and screws 87 are tightened to bias main housing cover 32b against main housing 32a. As a result, gasket compression ridges 84 compress the potting gasket along a closed annular sealing line around each of user interface elements 48, achieving a liquid-tight joint. Finally, a transparent sticker 88 bearing printed symbols is applied to the exterior of main housing cover 32b to provide a waterproof and dustproof outer layer covering the user interface elements.

[0078] Figure 15 Shown along Figure 3 A cross section of the final battery pack 20 taken along the plane XV-XV indicated in FIG, and wherein the main body of the potting resin 80 is omitted ( Figure 11B ) and potting case 78. The gasket pressing ridge 78d (not shown) of the potting case 78 presses the potting gasket 52 along the outer sealing line 90, while the gasket pressing ridge 84 of the cover 32 extends through the potting case opening ( Figure 10A ) and compress the potting gasket 52 within the periphery of the outer sealing line 90.

[0079] Leaving the wireless transceiver module 44 unpotted allows it to be removed from the potted circuit board 46, for example, for replacement. In an alternative manufacturing sequence, the circuit board 46 can be potted according to the potting procedure described above, followed by connection of the wireless transceiver module 44. Alternatively, the area of ​​the circuit board 46 reserved for the wireless transceiver module 44 can be located within the seal line 90 without being potted. Following this procedure, the wireless transceiver module 44 can be an optional accessory that can be optionally connected to the unpotted area after potting.

[0080] Figure 16 The process diagram schematically summarizes a method 100 for manufacturing the rechargeable battery pack 20 described above. The method (including several optional method steps) comprises the following steps:

[0081] 101: Provide circuit board 46 ( Figure 6 ), the first battery cell holder 62a and the second battery cell holder 62b ( Figure 7 ) and a plurality of battery cells 56 ( Figure 7 );

[0082] 102: Connect the first battery cell end 58a ( Figure 7 ) is positioned in the first battery cell holder 62a;

[0083] 103: Connect the second battery cell end 58b ( Figure 7 ) positioned in the second battery cell holder 62b;

[0084] 104: Position the circuit board 46 to align with the circuit board connector terminal edges 66a, 66b of the first and second battery cell holders 62a, 62b ( Figure 7 ) adjacent to each other, so that the inner surface 46a of the circuit board 46 ( Figure 6 ) faces the battery cell 56, and the outer side 46b of the circuit board 46 ( Figure 6 ) away from the battery cell 56;

[0085] 105: Connect the first set of cell holder terminals 63a of the first battery cell holder 62a ( Figure 8B ) through a set of welding gaps 75 ( Figure 7 ) are welded to the battery cell terminals 60a of the first group of battery cell ends 58a ( Figure 7 );

[0086] 106: Connect the second group of cell holder terminals 63b of the second battery cell holder 62b ( Figure 7) battery cell terminals 60b welded to the second set of battery cell ends 58b via a set of weld gaps 75 through the second cell holder 62b;

[0087] 107: Place the first cell holder cover 76a ( Figure 7 ) is applied to the outer surface 68a of the first cell holder 62a ( Figure 7 ) to cover a set of welding gaps 75 passing through the first cell holder 62a;

[0088] 108: Place the second cell holder cover 76b ( Figure 7 ) is applied to the outer side 68b of the second cell holder 62b ( Figure 7 ) to cover a set of welding gaps 75 passing through the second cell holder 62b;

[0089] 109: Electrically connect the circuit board terminal 64a of the first battery cell holder 62a and the circuit board terminal 64b of the second battery cell holder 62b to the circuit board 46;

[0090] 110: Place the potting gasket 52 ( Figure 6 ) is positioned between the circuit board 46 and the potting case 78 ( FIG. 10 ) to surround the user interface region 46 f and the transceiver mounting region 46 h of the circuit board 46 ( Figure 6 );

[0091] 111: Place the circuit board 46 and the circuit board connector terminal edge 66a of the first battery cell holder 62a and the circuit board connector terminal edge 66b of the second battery cell holder 62b ( Figure 7 ) is placed in a potting case 78, wherein the outer face 46b of the circuit board 46 faces downward and the first battery cell holder 62a and the second battery cell holder 62b extend upward from the potting case 78, and wherein a potting case opening 78c (FIG. 10) is aligned with the user interface area 46f and the transceiver mounting area 46h;

[0092] 112: compressing the potting gasket 52 by pressing the circuit board 46 against the potting shell 78, and optionally locking the potting shell relative to the circuit board with the potting gasket 52 in the compressed state, for example by attaching battery cell holders 62a, 62b to the potting shell 78, so that when the potting resin is filled in the potting shell 78, the potting gasket 52 prevents the potting resin from reaching the user interface area 46f and the transceiver mounting area 46h;

[0093] 114: Fill the potting resin into the potting shell 78 to form a circuit board 46 and the circuit board connector terminal edge 66a of the first battery cell holder 62a and the circuit board connector terminal edge 66b of the second battery cell holder 62b ( Figure 7) a coherent body 80 at least partially embedded in a potting resin ( Figure 11B );

[0094] 116: Provide the main housing cover 32b of the outer battery pack housing 32;

[0095] 118: By pressing the main housing cover 32b of the outer battery housing 32 against the potting shell opening 78c ( Figure 10A ) to compress the potting gasket 52 within the periphery of the outer battery housing 32 so as to achieve a sealed engagement between the cover 32 c of the outer battery housing 32 and the circuit board 46 via the potting gasket 52; and

[0096] 120: Fix the outer battery pack housing relative to the circuit board.

[0097] The invention has mainly been described above with reference to a few embodiments. However, as is readily appreciated by a person skilled in the art, other embodiments than the ones disclosed above are equally possible within the scope of the invention, as defined by the appended patent claims.

[0098] For example, the present invention has been described with reference to a chainsaw battery pack. However, it should be understood that the teachings herein are equally applicable to other rechargeable battery packs intended for use in wet and / or dirty areas.

[0099] In the claims, the word "comprising" does not exclude other elements or steps, and the indefinite article "a" or "an" does not exclude a plurality.

Claims

1. A rechargeable battery pack (20) configured to be removably attached to a handheld battery-powered power tool (10), the rechargeable battery pack (20) comprising: a plurality of elongated, rechargeable battery cells (56), each of the battery cells extending in a longitudinal direction (B) between a pair of opposing battery cell ends (58a, 58b), the pair of battery cell ends (58a, 58b) including battery cell terminals (60a, 60b) of opposite polarity; a circuit board (46) including control electronics; a first battery cell holder (62a) configured to receive a first group of battery cell ends (58a) including one end of each battery cell of the plurality of battery cells (56), the first battery cell holder (62a) including a first group of battery cell holder terminals (63a) and a first group of circuit board terminals (64a), the first group of battery cell holder terminals being connected to the battery cell terminals (60a) of the first group of battery cell ends (58a), the first group of circuit board terminals being arranged along a circuit board connector terminal edge (66a) of the first battery cell holder (62a), the first group of circuit board terminals (64a) being connected to a first terminal connection area (46e) of the circuit board (46); and a second battery cell holder (62b) configured to receive a second group of battery cell ends (58b) including the other end of each battery cell in the plurality of battery cells (56), the second battery cell holder (62b) including a corresponding group of battery cell holder terminals (63b) and a second group of circuit board terminals (64b), the corresponding group of battery cell holder terminals being connected to the battery cell terminals (60b) of the second group of battery cell ends (58b), the second group of circuit board terminals being arranged along a circuit board connector terminal edge (66b) of the second battery cell holder (62b), the second group of circuit board terminals (64b) being connected to a second terminal connection area (46d) of the circuit board (46), wherein the first battery cell holder (62a) is partially embedded in a continuous body (80) of potting resin, wherein the first group of circuit board terminals (64a), the first terminal connection area (46e) and the circuit board connector terminal edge (66a) of the first battery cell holder (62a) are embedded in the continuous body (80) of potting resin.

2. The rechargeable battery pack (20) according to claim 1, wherein: The second terminal connection area (46d), the second set of circuit board terminals (64d) and the circuit board connector terminal edge (66b) of the second battery cell holder (62b) are embedded in a continuous body (80) of the potting resin.

3. A rechargeable battery pack (20) according to any one of the preceding claims, wherein: At least some of the plurality of battery cells (56) are located outside of the coherent body (80) of potting resin.

4. The rechargeable battery pack (20) of any preceding claim, comprising air gaps (82) between adjacent battery cells (56).

5. The rechargeable battery (20) of claim 4, comprising an outer battery housing (32) provided with a ventilation opening (34a; 34b) in fluid communication with the air gap (82).

6. A rechargeable battery pack (20) according to any one of the preceding claims, wherein The circuit board (46) includes an inner surface (46a) facing the plurality of battery cells (56) and an outer surface (46b) facing away from the plurality of battery cells (56).

7. The rechargeable battery pack (20) according to claim 6, wherein: The inner face of the circuit board (46) is embedded in a continuous body (80) of potting resin.

8. The rechargeable battery pack (20) according to claim 7, wherein: The rechargeable battery pack (20) includes an electrical connector (36) for connecting to a handheld battery-powered power tool (10) and a set of connector leads (54) extending between the circuit board (46) and the electrical connector (36), wherein the connector leads (54) extend from an inner face (46a) of the circuit board (46) through the continuous body (80) of the potting resin.

9. The rechargeable battery pack (20) according to any one of claims 6 to 7, wherein: An outer face (46b) of the circuit board (46) is at least partially embedded in a coherent body (80) of potting resin.

10. The rechargeable battery pack (20) according to claim 9, wherein The coherent body (80) of potting resin is bonded to a potting shell (78) that at least partially surrounds the coherent body (80) of potting resin.

11. The rechargeable battery pack (20) according to claim 10, wherein: The outer surface (46b) of the circuit board (46) includes a user interface area (46f) and a potting gasket (52), wherein the user interface area includes a plurality of user interface elements (48) not covered by the coherent body (80) of the potting resin, the potting gasket surrounds the user interface area (46f) and is adjacent to the coherent body (80) of the potting resin, and the potting gasket (52) is pressed by a gasket pressure ridge (78d) on the inner surface of the potting shell (78).

12. The rechargeable battery pack (20) according to claim 11, wherein The potting shell (78) is provided with a potting shell opening (78c) aligned with the user interface area (46f), wherein the user interface area (46f) is not covered by the coherent body (80) of potting resin.

13. The rechargeable battery pack (20) of claim 12, further comprising an outer battery pack housing (32) provided with a gasket pressing ridge (84), the gasket pressing ridge extending through the potting case opening (78c) toward the circuit board (46), wherein The potting gasket (52) is pressed by the gasket pressing ridge (84) of the outer battery pack housing (32).

14. The rechargeable battery pack (20) according to claim 13, wherein: The potting gasket (52) includes a plurality of gasket apertures (52a) each surrounding a corresponding user interface element (48), and a gasket pressing ridge (84) of the outer battery pack housing (32) compresses the potting gasket (52) in a closed annular structure around the corresponding gasket apertures (52a).

15. The rechargeable battery pack (20) according to any one of claims 11 to 14, wherein: The potting gasket (52) is configured as a continuous foam rubber sheet.

16. A rechargeable battery pack (20) according to any one of the preceding claims, wherein The circuit board (46) extends in a circuit board plane (P), and wherein the total height (H) of the coherent body (80) of the potting resin in a direction perpendicular to the circuit board plane (P) is less than 40 mm.

17. A rechargeable battery pack (20) according to any one of the preceding claims, wherein The cell holder terminals (63a) of the first set of cell holder terminals are at least partially molded into the first battery cell holder (62a).

18. A rechargeable battery pack (20) according to any one of the preceding claims, wherein The first battery cell holder (62a) has an outer surface (68a) facing away from the battery cell (56) and an inner surface (70a) receiving the first group of battery cell ends (58a), wherein the first battery cell holder (62a) is provided with a set of gaps (75) aligned with the battery cell terminals (60a) of the first group of battery cell ends (58a), and the gaps (75) expose the first group of battery cell holder terminals (63a) on the outer surface (68a) of the first battery cell holder (62a).

19. The rechargeable battery pack (20) of claim 18, further comprising a flexible cell holder cover (76a), the cell holder cover being located on the exterior (68a) of the first battery cell holder (62a), the cell holder cover (76a) covering the set of gaps (75) exposing the first set of battery cell holder terminals (63a) on the exterior (68a) of the first battery cell holder (68).

20. The rechargeable battery pack (20) according to claim 19, wherein The first battery cell holder cover (76a) is a foam rubber sheet.

21. A rechargeable battery pack (20) configured to be removably attached to a handheld battery-powered power tool (10), such as defined in any one of the preceding claims, the rechargeable battery pack (20) comprising: A plurality of elongated and rechargeable battery cells (56); a circuit board (46) comprising control electronics, the circuit board (46) comprising a transceiver mounting area (46h), the transceiver mounting area comprising a wireless transceiver module (44), wherein the circuit board (46) is partially embedded in a coherent body (80) of potting resin, and wherein the transceiver mounting area (46h) is not covered by the coherent body (80) of potting resin; and a potting gasket (52) adjacent to the continuous body (80) of potting resin and separating the transceiver mounting area (46h) from the continuous body (80) of potting resin, The wireless transceiver module (44) is individually overmolded with a plastic overmold (44c), wherein the plastic overmold (44c) includes a sealing ridge (44d) extending into a closed annular structure on the bottom surface of the wireless transceiver module (44), the sealing ridge sealingly abutting the circuit board (46).

22. The rechargeable battery pack (20) according to claim 21, wherein The bottom surface of the wireless transceiver module (44) includes a set of connection terminals (44f) that are connected but not soldered to a set of mating connection terminals of the circuit board (46), wherein the wireless transceiver module (44) is biased to the circuit board (46).

23. A rechargeable battery pack (20) configured to be removably attached to a handheld battery-powered power tool (10), such as defined in any one of the preceding claims, the rechargeable battery pack (20) comprising: a plurality of rechargeable battery cells (56); as well as A circuit board (46) comprising control electronics, wherein the circuit board (46) comprises an inner face (46a) facing the plurality of battery cells (56) and an outer face (46b) facing away from the plurality of battery cells (56), wherein the outer face (46b) of the circuit board (46) comprises a user interface area (46f), the user interface area comprising a plurality of user interface elements (48), wherein the outer face (46b) of the circuit board (46) is partially embedded in a coherent body (80) of potting resin, the coherent body being bonded to a potting shell (78), the potting shell at least partially surrounding the outer face (46b) of the circuit board (46) and the coherent body (80) of potting resin, wherein the potting shell (78) is provided with a potting shell opening (78c) aligned with the user interface area (46f), and the user interface area (46f) is not covered by the coherent body (80) of potting resin, The rechargeable battery pack (20) further includes a potting gasket (52) surrounding the user interface area (46f) and abutting the continuous body (80) of the potting resin, the potting gasket (52) being compressed between the circuit board (46) and a gasket pressure ridge (78d) on the inner face (78a) of the potting case (78), wherein the gasket pressure ridge (78d) defines a closed annular structure extending around the potting case opening (78c).

24. The rechargeable battery pack (20) of claim 23, further comprising an outer battery pack housing (32), the outer battery pack housing being provided with a gasket pressing ridge (84), the gasket pressing ridge extending through the potting shell opening (78c) toward the circuit board (46), wherein The potting gasket (52) is pressed by the gasket pressing ridge (84) of the outer battery pack housing (32).

25. A combination of a rechargeable battery pack (20) according to any one of the preceding claims and a handheld battery-powered power tool (10), the handheld battery-powered power tool comprising a battery connector (30) adapted to be connected to the rechargeable battery pack (20).

26. A method of manufacturing a rechargeable battery pack (20), comprising: A circuit board (46), a first battery cell holder (62a), a second battery cell holder (62b), and a plurality of battery cells (56) are provided, wherein the first battery cell holder includes a corresponding set of circuit board terminals arranged along a circuit board connector terminal edge (66a) of the first battery cell holder (62a), and the second battery cell holder includes a corresponding set of circuit board terminals (64b) arranged along a circuit board connector terminal edge (66b) of the second battery cell holder (62b); positioning a first group of battery cell ends (58a) of the plurality of battery cells (56) in the first battery cell holder (62a); positioning a second group of battery cell ends (58b) of the plurality of battery cells (56) in the second battery cell holder (62b); positioning the circuit board (46) adjacent to the circuit board connector terminal edges (66a, 66b) of the first and second battery cell holders (62a, 62b) such that an inner face (46a) of the circuit board (46) faces the plurality of battery cells (56) and an outer face (46b) of the circuit board (46) faces away from the plurality of battery cells (56); electrically connecting circuit board terminals (64a, 64b) of the first battery cell holder and the second battery cell holder (62a, 62b) to the circuit board (46); placing the circuit board (46) and the circuit board connector terminal edges (66a, 66b) of the first battery cell holder and the second battery cell holder (62a, 62b) in a potting shell (78) shaped like a tray, wherein the outer surface (46b) of the circuit board (46) faces downward into the potting shell (78), and the first battery cell holder and the second battery cell holder (62a, 62b) extend upward from the potting shell (78); as well as A potting resin is filled into the potting shell (78) to form a coherent body (80) of potting resin in which the circuit board (46) and the circuit board connector terminal edges (66a, 66b) of the first and second battery cell holders (62a, 62b) are at least partially embedded.

27. The method according to claim 26, comprising: Before filling the potting resin into the potting shell (78), Positioning a potting gasket (52) between the circuit board (46) and the potting case (78), the potting gasket (52) surrounding the user interface area (46f) and / or the transceiver mounting area (46h) of the circuit board (46); and The potting gasket (52) is compressed by pressing the circuit board (46) against the potting case (78), so that when potting resin is filled in the potting case (78), the potting gasket (52) prevents the potting resin from reaching the user interface area (46f) and / or the transceiver mounting area (46h).

28. The method according to claim 27, wherein The potting case (78) is provided with a potting case opening (78c) aligned with the user interface area (46f) and / or the transceiver mounting area (46h), and the method further comprises: providing an outer battery pack housing (32); and Compressing the potting gasket (52) by pressing the outer battery housing (32) against the potting gasket (52) within the periphery of the potting shell opening (78c) to achieve a sealed joint between the outer battery housing (32) and the circuit board (46) via the potting gasket (52); and The outer battery pack housing (32) is secured relative to the circuit board (46).

29. The method according to any one of claims 26 to 28, further comprising: welding a set of cell holder terminals (63a) of the first battery cell holder (62a) to the battery cell terminals (60a) of the first set of battery cell ends (58a) via a set of gaps (75) passing through the first battery cell holder (62a); welding a set of cell holder terminals (63b) of the second battery cell holder (62b) to the battery cell terminals (60b) of the second set of battery cell ends (58b) via a set of gaps (75) passing through the second battery cell holder (62b); applying a flexible first cell holder cover (76a) to an outer face (68a) of the first battery cell holder (62a) to cover a set of gaps (75) through the first cell holder (62a); and A flexible second cell holder cover (76b) is applied to the outer face (68b) of the second battery cell holder (62b) to cover a set of gaps (75) through the second battery cell holder (62b).

Images