Battery pack with at least one protective element

Abstract

The invention relates to a battery pack, in particular a battery pack for a hand-held power tool, comprising a housing in which at least one battery cell is arranged, with at least one protective element designed to protect the battery pack in the event of force and / or penetration. It is proposed that the protective element be arranged on an outer surface of the battery pack housing.

Description

State of the art

[0001] DE 10 2018 210 663 A1 describes a hand-held power tool with a protective element, wherein the protective element is accommodated in the housing of the hand-held power tool. Disclosure of the invention

[0002] The invention relates to a battery pack, in particular a battery pack for a handheld power tool, comprising a housing in which at least one battery cell is arranged, with at least one protective element designed to protect the battery pack against the impact of force and / or penetration. It is proposed that the protective element be arranged on an outer side of the housing of the battery pack. This advantageously allows for effective protection of the battery pack.

[0003] The battery pack is in particular part of a system comprising the battery pack and a consumer, wherein the consumer is supplied with energy via the battery pack during operation. The battery pack is in particular designed as a handheld power tool battery pack. The battery pack is in particular designed as a removable battery pack. The battery pack is in particular designed as a removable battery pack. The electrical consumer can alternatively also be designed as a means of transport, for example an electric bicycle, as a household appliance, for example a vacuum cleaner, as a gardening tool, for example a hedge trimmer, or as a measuring device.

[0004] The housing of the battery pack is preferably designed as an outer housing. The battery pack, in particular the housing of the battery pack, can be detachably connected to the consumer and / or a charging device via a mechanical interface. The housing of the battery pack can have one or more housing parts. The battery pack can have a cell holder which is designed to receive and / or secure the battery cells in the housing. The cell holder preferably has individual cell receptacles, each of which is designed to receive an individual battery cell. The cell holder is preferably designed as one of the housing parts. The housing parts are connected to one another in a force-fitting, form-fitting, and / or material-fitting manner. The cell holder is preferably made of a plastic, in particular a thermoplastic. The cell holder can partially form the outer housing of the battery pack. The cell holder is preferably designed as a single part or in one piece.In the context of this application, "one-piece" is understood to mean, in particular, a component that is formed from a single piece and not from multiple components that are connected to one another in a materially bonded and / or force-fitting and / or positive-locking manner. A one-piece component therefore consists of a single material. In the context of this application, "one-piece" is understood to mean, in particular, a single component or multiple components that are connected to one another in a materially bonded manner, for example, via a 2K injection molding process. Alternatively, it is also conceivable for the cell holder to be formed from multiple parts, with the different parts being connected to one another in a force-fitting and / or positive-locking manner.

[0005] The battery pack can be connected to the consumer device in a force-fitting and / or form-fitting manner via the mechanical interface. The mechanical interface advantageously comprises at least one actuating element via which the connection between the battery pack and the consumer device and / or the charging device can be released. The actuating element can be designed, for example, as a button, lever or push-button. In addition, the battery pack has at least one electrical interface via which the battery pack can be electrically connected to the consumer device and / or the charging device. The battery pack can, for example, be charged and / or discharged via the electrical connection. Alternatively or additionally, it is also conceivable for information to be transmitted via the electrical interface. The electrical interface is preferably designed as a contact interface in which the electrical connection is established via physical contact between at least two conductive components.The electrical interface preferably comprises at least two electrical contact elements. In particular, one of the electrical contact elements is designed as a positive contact and the other electrical contact element as a negative contact. In addition, the electrical interface can have at least one additional contact designed to transmit additional information to the consumer and / or to the charging device. Alternatively or additionally, the electrical interface can have a secondary charging coil element for inductive charging. Furthermore, the at least one battery cell, which can be electrically connected to the consumer via the electrical contact device, is arranged in the housing of the battery pack.

[0006] The battery cell can be designed as a galvanic cell with a structure in which one cell pole is located at one end and another cell pole at an opposite end. In particular, the battery cell has a positive cell pole at one end and a negative cell pole at an opposite end. The battery cells are preferably designed as NiCd or NiMh, particularly preferably as lithium-based battery cells or Li-Ion battery cells. The battery voltage of the battery pack is generally a multiple of the voltage of an individual battery cell and results from the connection (parallel or series) of the battery cells. For common battery cells with a voltage of 3.6 V, this results in exemplary battery voltages of 3.6 V, 7.2 V, 10.8 V, 14.4 V, 18 V, 36 V, 54 V, 108 V, etc. The battery cell is preferably designed as an at least substantially cylindrical round cell, with the cell poles arranged at the ends of the cylinder shape.

[0007] Furthermore, the battery pack preferably comprises electronics. The electronics can comprise a memory unit on which information is stored. Additionally or alternatively, it is also conceivable for information to be determined by the electronics. The information can be, for example, a charge level of the battery pack, a temperature within the battery pack, a code or a remaining capacity of the battery pack. It is also conceivable for the electronics to be designed to regulate or control the charging and / or discharging process of the battery pack. The electronics can, for example, have a computing unit, a control unit, a transistor, a capacitor, and / or the memory unit. The electronics can also have one or more sensor elements, for example a temperature sensor for determining the temperature within the battery pack or a motion sensor for detecting movements.Alternatively or additionally, the electronics may comprise a coding element, such as a coding resistor.

[0008] The outer side of the housing is arranged facing away from the inner side of the battery pack housing. The inner side of the housing faces the battery cells. The protective element is designed such that, for example, in the event of the battery pack falling onto the ground or onto a sharp or pointed object, such as a nail, the impact on the housing is significantly reduced. The protective element is preferably made of a different material than the battery pack housing. The protective element is designed in particular such that a force acting on the battery pack housing is reduced by elastic and / or plastic deformation of the protective element. The deformation can be reversible or completely irreversible.

[0009] Furthermore, it is proposed that the battery pack have a base arranged on a side of the battery pack opposite the mechanical interface. In particular, the at least one protective element is arranged in the region of the base. This advantageously optimizes protection. Alternatively or additionally, an arrangement in an edge region or on a side adjacent to the base of the battery pack is conceivable. Alternatively or additionally, it is also conceivable to arrange at least one protective element in the region of the mechanical interface.

[0010] It is further proposed that the at least one protective element be integrally formed with the housing of the battery pack by a material fit, force fit, and / or form fit. The material fit can be achieved, for example, by adhesive bonding. The protective element can also be partially overmolded by the housing of the battery pack and / or be molded onto the housing of the battery pack.

[0011] It is also proposed that the protective element be movably, in particular rotatably, connected to the housing. The force applied can advantageously be reduced by a relative movement of the protective element relative to the housing.

[0012] Furthermore, it is proposed that the protective element be designed such that a cavity is formed between the protective element and the housing, wherein at least one side of the cavity is open, wherein the open side of the cavity extends in particular along a longitudinal extent of at least one battery cell. Preferably, the cavity is open on at least two, preferably at least three, adjacent sides. The protective element is designed in particular such that the cavity is reduced in size when a force is applied.

[0013] It is further proposed that the protective element only partially cover the base. The coverage is preferably less than 90% of the base, preferably less than 50% of the base, and more preferably less than 30% of the base. This advantageously reduces the weight of the battery pack.

[0014] Alternatively or additionally, it is proposed that the at least one protective element and the housing be formed integrally. In particular, the protective element extends obliquely to the base of the battery pack.

[0015] The protective element preferably extends in a range between 20° and 60° relative to the base, in particular in a range between 25° and 45° relative to the base. The protective element is preferably designed as a flat surface with a constant slope relative to the base. The housing can have a plurality of protective elements, with all protective elements preferably having the same slope. Alternatively, it is also conceivable for the protective elements to have different slopes.

[0016] It is also proposed that the battery pack have at least one additional protective element, wherein the additional protective element is arranged within the battery pack, wherein the additional protective element is arranged between the at least one battery cell and the base. This advantageously allows the protection of the battery pack to be further optimized. The additional protective element is thus designed as an internal protective element.

[0017] Furthermore, it is proposed that the additional protective element be designed to apply a radial force to the at least one battery cell in a cell receptacle. The cell receptacle is in particular part of a cell holder for accommodating the battery cells. This can advantageously improve the fastening of the battery cells and their protection.

[0018] It is further proposed that the additional protective element be harder than the housing and / or the outer protective element, in particular, wherein the additional protective element is formed, in particular, from a plastic. In particular, the additional protective element is formed from an entropy-elastic material, preferably from rubber. Drawings

[0019] Further advantages will become apparent from the following description of the drawings. The drawings, the description, and the claims contain numerous features in combination. Those skilled in the art will expediently consider the features individually and combine them into further meaningful combinations. Reference symbols of features of different embodiments of the invention that are essentially identical are provided with the same number and a letter identifying the embodiment.

[0020] They show: Fig. 1 a schematic side view of a hand tool with a battery pack; Fig. 2 an exploded view of the battery pack; Fig. 3 a section through the battery pack in the area of ​​the protective elements; Fig. 4 a section through the battery pack according to Fig. 3 in a tilted state of a protective element; Fig. 5 shows a further embodiment of a battery pack with protective elements; Fig. 6 a longitudinal section through the battery pack according to Fig. 5; Fig. 7 a cross-section through the battery pack according to Fig. 5. Description of the embodiments

[0021] In Fig. 1 shows a side view of a system 10 comprising an electrical load 14 embodied as a handheld power tool 12 and a battery pack 18 embodied as a handheld power tool battery pack 16. The handheld power tool 12 is thus embodied as a cordless handheld power tool and is supplied with energy during operation via the battery pack 18. The handheld power tool 12 and the battery pack 18 each have a mechanical interface 20, 22 via which the two components of the system 10 are detachably connected to one another. The battery pack 18 is thus embodied as an interchangeable battery pack and can be replaced with an identical or a similar battery pack. The handheld power tool 12 is embodied, for example, as a hammer drill. The battery pack 18 is also detachably connectable to a charging device (not shown) via the mechanical interface 22 of the battery pack 18.

[0022] The handheld power tool 12 has a housing 26, at the rear end of which a handle 28 with an operating switch 30 for switching the handheld power tool 12 on and off is arranged. At the front end of the housing 26 of the handheld power tool 12, a tool holder 31 is arranged, which is intended to receive an insert tool 32. A drive unit 38 having an electric motor 34 and a gear system 36 is arranged between the handle 28 and the tool holder 31. The gear system 36 comprises an impact mechanism unit 40 and is arranged above the electric motor 34. The impact mechanism unit 40 comprises a pneumatic impact mechanism. Below the electric motor 34, an electronics unit 42 is arranged, via which the handheld power tool 12 can be regulated or controlled. The battery pack 18 is arranged below the handle 28 and adjacent to the electronics unit 42.

[0023] The battery pack 18 and the battery pack 14 each have corresponding electrical interfaces 44, 46, via which the battery pack 18 can be electrically connected to the consumer 14, in particular the electronics 42 of the consumer 14. When connected to each other, the battery pack 18 provides the power supply for the consumer 14.

[0024] In Fig. Figure 2 shows an exploded view of the battery pack 18. The battery pack 18 has a housing 50. The housing 50 of the battery pack 18 is made, for example, of a plastic, in particular a hard plastic. The housing 50 of the battery pack 18 comprises several housing parts 52, which are connected to one another, for example, via connecting means 54 in the form of screws.

[0025] The upper housing part 52 is designed as an interface housing part 56 and comprises the electrical interface 44 and the mechanical interface 22 of the battery pack 18. When connected to the handheld power tool 12, the interface housing part 56 is largely concealed by the handheld power tool 12. The mechanical interface 22 has, for example, two guide elements 58 in the form of guide rails, which are designed to guide in corresponding guide elements of the electrical load 14 during the connection process. In addition, the battery pack 18 has a lock with a locking element 62. The locking element 62 is designed, for example, as a movable, in particular rotatable, locking element 62 and is preloaded in the direction of the locking position by a spring element (not shown). The lock also has an actuating element 64, which is designed to be manually actuated.The actuating element 64 is also mounted, for example, in the housing 50 of the battery pack 18, in particular in the interface housing part 56, for example in a linearly movable manner.

[0026] The battery pack 18 has, for example, ten battery cells 66 (see Fig. 3). The battery cells 66 are accommodated in a cell holder 70. The cell holder 70 is, for example, a single piece and made of a plastic. The cell holder 70 has an individual receptacle for each battery cell 66, into which the battery cells 66 can be inserted along their longitudinal extent. The individual cell receptacles are, for example, essentially closed. The battery cells 66 are, for example, cylindrical round Li-ion cells. The cell holder 70 can also be constructed in several parts and / or be partially open, so that the battery cells 66 are partially free laterally and spaced from a wall of the cell holder 70.

[0027] The cell holder 70 also forms part of the housing 50 and thus a housing part 52. For example, the cell holder 70 forms the area of ​​the housing 50 opposite the interface housing part 56 and partially a standing surface 68 on which the battery pack 18 can be placed on its own and / or when connected to the handheld power tool 12.

[0028] In total, the housing 50 comprises four housing parts 52, with the cell holder 70 being connected to the interface housing part 56 via two side housing parts 71. The connection is made by means of connecting means 54, for example, a screw connection. In addition, the housing 50 also comprises connecting means for a positive connection, for example, cylindrical cutouts in the side housing parts 71 for connecting to the cell holder.

[0029] Electronics 72 are also arranged in the housing 50 of the battery pack 18. The electronics 72 are arranged, for example, between the cell holder 70 and the interface housing part 56. The electronics 72 comprises a printed circuit board 74, which comprises electronic components and, for example, five electrical contact elements 76. The electrical contact elements 76 are designed, for example, as contact tulips. The two outer electrical contact elements 76 are designed, for example, as power contacts for the energy supply. The inner electrical contact elements 76 are designed, for example, as signal contacts, which are designed to transmit information to the handheld power tool 12 and / or the charger.

[0030] In Fig. Figure 3 shows a cross-section through the battery pack 18. The battery pack 18 has, for example, two protective elements 80 designed to protect the battery pack 18.

[0031] The battery pack 18 has, for example, two protective elements 80 that extend essentially parallel to the battery cells 66 and are arranged in the region of the base 68. The protective elements 80 have a length that essentially corresponds to the length of the battery cells 66. The protective elements 80 thus advantageously partially form the base 68. The protective elements 80 are, for example, made of a different material than the housing 50 of the battery pack 18. The protective elements 80 are, for example, connected to the housing 50 in a force-fitting and form-fitting manner. In particular, the protective elements 80 are partially arranged in an exemplary V-shaped groove 82 of the housing 50, in particular of the cell holder 70, and are clamped between the two side housing parts 71.

[0032] The protective elements 80 are, for example, made of a thermoplastic material. The plastic can be PA-GF, PC / ABS, or similar.

[0033] The protective elements 80 rest essentially linearly in the groove 82. Due to the partial support of the protective elements 80, a cavity 84 is formed between the protective elements 80 and the outer side of the housing 50, in particular the outer side of the cell holder 70. This advantageously allows a larger area of ​​the cell holder 70 connected to the battery cells 66 for heat dissipation to remain free, so that the cell holder 70 can be cooled by airflow.

[0034] If the battery pack 18 strikes an object on the ground in the event of a fall, such as a nail or a stone, this force or impact energy on the housing 50 can be reduced by the protective element 80, in that the protective element 80 deforms and / or moves in the direction of the cell holder 70 in such a way that the cavity 84 is reduced in size. The movement of the protective element 80 is designed, in particular, as a rotational movement, with an axis of rotation 83 being defined by the groove 82 in which the protective element 80 is arranged. Advantageously, the movement of the protective element 80 can deflect the foreign object in such a way that the force or damage / penetration of the battery cell is minimized. Fig. 4 the protective element 80 is shown in the tilted state.

[0035] The protective elements 80 have a substantially W-shaped cross-section. In the center, the protective elements 80 have a V-shaped notch 88. The notch 88 is designed such that in the event of a central force or a nail impact, the force is directed into an area where the material thickness of the protective element 80 and / or the housing 50 is greater.

[0036] Preferably, the protective element 80 is designed to be replaceable. It is also conceivable for the protective element 80 to be designed as an optional element of the battery pack 18, so that the battery pack 18, in particular the housing 50 of the battery pack 18, is fully functional even without the protective elements 80.

[0037] In Fig. Figure 5 shows an alternative embodiment of a battery pack 18a in a perspective view from below. The battery pack 18a has a similar structure to the previously described battery pack 18, but differs in the design of the protective elements 80a.

[0038] As previously described, the housing 50a of the battery pack 18a comprises four housing parts 52a, with the protective elements 80a being formed integrally with the cell holder 70a. The protective elements 80a are thus arranged on the underside of the battery pack 18a; alternatively or additionally, it is also conceivable to arrange the protective elements 80a on the side or on top.

[0039] The protective elements 80a are formed as pairs of tapered V-shaped slopes. The underside of the cell holder 70a is essentially completely covered by the protective elements 80a, with twelve protective elements 80a being arranged for protection per battery cell, for example.

[0040] The battery pack 18a is in Fig. 6 in a cross-section. The base surface 68a defines a plane from which the protective elements 80a extend diagonally inward. The angle between the base surface 68a and the protective element 80a is more than 30°, for example, approximately 35°. Alternatively, larger gradients, for example, more than 45°, are also conceivable to further enhance the protection.

[0041] Viewed in cross-section, the protective elements 80a are arranged such that the protective elements 80a have a minimum distance from the base surface 68a in the central region of the battery cells 66a and a maximum distance from the base surface 68a between the battery cells 66a. In particular, the protective elements 80a partially form the base surface 68a.

[0042] As an alternative to the described one-piece embodiment of the protective elements 80a, it is also conceivable for the protective elements 80a to be formed as a coating with a harder or more elastic material, in particular a plastic. It is also conceivable for the protective elements 80a to be formed from a metal, preferably from a metallic insert in a receptacle provided for this purpose in the housing 50a.

[0043] It is also conceivable that the plurality of protective elements 80a is not distributed over the entire base 68a, but is only used at critical points where, for example, the housing 50a of the battery pack 18a, in particular the cell holder 70a, has a weaker material thickness.

[0044] In addition, the battery pack 18a has additional protective elements 90a, which are intended to protect the battery cells 66a.

[0045] The further protective elements 90a are designed in particular as internal protective elements that are arranged inside the housing 50a of the battery pack 18a, in particular on an inner side of the housing 50a of the battery pack 18a. For example, the housing 50a of the battery pack 18a has a protective element receptacle 92a on its inner side, which is designed to receive the further protective element 90a. The protective element receptacle 92a is arranged adjacent to an individual cell receptacle 94a of the cell holder 70a. The individual cell receptacles 94a of the cell holder 70a are each designed to receive a single battery cell 66a. The individual cell receptacles 94a are hollow cylindrical and have a diameter that essentially corresponds to a diameter of the battery cells 66a. The individual cell receptacle 94a has an axial opening (not shown) for receiving the battery cell 66a and a radially circumferential wall 96a.The wall 96a is essentially closed and is interrupted only by the protective element receptacle 92a.

[0046] The additional protective element 90a is, for example, formed from an elastic plastic, in particular from a soft plastic. In particular, the additional protective element 90a has greater elasticity than the housing 50a, in particular than the cell holder 70a. Preferably, the additional protective element 90a is formed from an entropy-elastic material that, when penetrating a damaging body, exhibits increased robustness due to an advantageous distribution of the introduced energy. The additional protective elements 90a are also designed such that a radially inward force acts on the battery cells 66a through the additional protective elements 90a to fix the battery cells 66a in the individual cell receptacles 94a.

[0047] The battery pack 18a may have one or more additional protective elements 90a for each battery cell 66a. As shown in Fig. 7 in a cross-section, the battery pack 18a has two further protective elements 90a for each battery cell 66a, which extend coaxially to one another along the longitudinal extent of the battery cells 66a.

[0048] Alternatively, it is also conceivable for the additional protective element 90a to have a greater hardness than the housing 50a of the battery pack 18a, in particular than the cell holder 70a. This can be realized, for example, by a plastic with a greater hardness or a metal, in particular a metal sheet.

[0049] In order to optimally protect the battery cells 66a from damage, the further protective element 90a and the protective elements 80a are arranged opposite one another on different sides of the housing 50, in particular of the cell holder 70a. QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] DE 10 2018 210 663 A1

[0001]

Claims

[1] Battery pack, in particular battery pack (18) for a hand-held power tool (12), comprising a housing (50) in which at least one battery cell (66) is arranged, with at least one protective element (80) which is designed to protect the battery pack (18) in the event of a force and / or penetration, characterized by that the protective element (80) is arranged on an outer side of the housing (50) of the battery pack (18). [2] Battery pack according to claim 1, characterized by that the battery pack (18) has a mechanical interface (22) for detachable connection to a consumer (14), in particular to a hand-held power tool (12). [3] Battery pack according to one of the preceding claims, characterized by that the battery pack (18) has a base (68) which is arranged on a side of the battery pack (18) opposite the mechanical interface (22). [4] Battery pack according to one of the preceding claims, characterized bythat the at least one protective element () is arranged in the area of ​​the standing surface (). [5] Battery pack according to one of the preceding claims, characterized by that the at least one protective element (80) is formed in a materially bonded or force- and / or form-fitting manner with the housing (18) of the battery pack (18). [6] Battery pack according to one of the preceding claims, characterized by that the protective element (80) is movably, in particular rotatably, connected to the housing (50). [7] Battery pack according to one of the preceding claims, characterized by that the protective element (80) is designed such that a cavity (84) is formed between the protective element (80) and the housing (50), wherein at least one side of the cavity (84) is open, wherein the open side of the cavity (84) extends in particular along a longitudinal extent of the at least one battery cell (66). [8] Battery pack according to one of the preceding claims, characterized by that the protective element (80) only partially covers the base (68). [9] Battery pack according to one of the preceding claims, characterized by that the at least one protective element (80a) and the housing (50a) are formed in one piece. [10] Battery pack according to one of the preceding claims, characterized by that the at least one protective element (80a) extends obliquely to the standing surface (68a). [11] Battery pack according to one of the preceding claims, characterized by that the protective element (80a) extends in a range between 20° and 60° to the standing surface (68a), in particular in a range between 25° and 45° to the standing surface (68a). [12] Battery pack according to one of the preceding claims, characterized bythat the battery pack (18a) has at least one further protective element (90a), wherein the further protective element (90a) is arranged in the battery pack (18a), wherein the further protective element (90a) is arranged between the at least one battery cell (66a) and the standing surface (68a). [13] Battery pack according to claim 12, characterized by that the further protective element (90a) is designed to radially apply a force to the at least one battery cell (66a) in a cell receptacle, in particular a single cell receptacle (94a). [14] Battery pack according to one of claims 12 or 13, characterized by that the further protective element (90a) has a greater hardness than the housing (50a) and / or the protective element (80a), wherein the further protective element (90a) is formed in particular from a plastic. [15] Battery pack according to one of claims 12 to 14, characterized bythat the further protective element (90a) is formed from an entropy-elastic material, in particular from a rubber.

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